EACH_Qualifying_Applications_2015_by_CountryLast week the check of eligibility and ranking of the EACH applications was completed and Thursday-Friday the admission notifications were sent out to all eligible candidates.

We are glad to announce that there were altogether 46 qualifying applications, which were ranked based on the average grade of the previous study level and on the contents of the motivation letter (as is explained in the EACH admission page). 13 EU scholarships were offered (ten to partner country applicants and three to programme country applicants). The remaining qualifying applicants were offered either a tuition waiver scholarship a fee-based study place, based on their position in the ranking list. The coverage of the scholarships is explained in the EACH Scholarships page.

Most probably not all applicants who were awarded the EU scholarship will accept the study place, therefore it is still possible that the applicants who are topmost in the list of tuition waiver scholarship awardees will receive the EU scholarship (in principle, all qualifying candidates are in the “reserve list” for the EU scholarship). In order to proceed with the admission process it is requested that all applicants who received admission notification will inform us of their decision as soon as possible and in any case not later than on March 23, 2015.

We thank all the applicants for their interest in the EACH programme and we hope that those who will start their studies in EACH will have a useful and enjoyable study experience!

 

Binding_of_acetate_lactate_benzoate_trimethylacetate_to_different_receptorsStudies of host-guest chemistry, in particular, binding of anions by synthetic receptors has become a prominent research topic at the Analytical chemistry research group at UT. This fundamental research prepares ground for developing sensor devices for fast and selective anion determination. Carboxylate anions are among the most interesting, because the carboxylate group is by far the most widespread anionic group in biological objects.

One of the challenges lies in the fact that it is not easy to design synthetic receptors that have very high binding affinity towards a given carboxylate anion and are insensitive towards all others. Thus, it is envisaged that rather than designing highly selective individual receptor molecules, it may be more practical to utilize a number of receptor molecules, having different affinities for different anions, as a receptor array. Applying chemometric tools to the responses (e.g. optical or potentiometric) from such arrays it is in principle possible to determine individual anions from mixtures.

At our group highly accurate methods anion-receptor binding constant (logKass) measurement have been developed recently, based on UV-Vis spectrophotometry (J. Org. Chem. 2013, 78, 7796−7808) and NMR spectrometry (J. Org. Chem. 2014, 79, 2501−2513). Applying these methods, the binding constants of small synthetic receptor molecules based on indolocarbazole, carbazole, indole, urea and some others, as well as their combinations were measured for small carboxylate anions of different basicity, hydrophilicity and steric demand: trimethylacetate, acetate, benzoate and lactate. As a result, four separate binding affinity scales (ladders) including thirty-eight receptors were obtained. The results are graphically depicted in the Figure on the left. The high accuracy of the measurement methods enables distinguishing between small changes in binding affinity. It can be seen that many “crossing” points between the lines (denoting switching of affinity orders) exist, which are the basis of designing useful receptor arrays. This work has recently been published (Chem. Eur. J. 2015, DOI: 10.1002/chem.201405858) and presented in the SupraChem 2015 conference (see the presentation).

 

Work is in progress to measure the binding constants between more anions and receptors with different molecular structures with the aim of compiling the most voluminous dataset available for predicting trends in anion-receptor binding as function of the structural features of the anions and the receptors.

 

UT_Measurement_Uncertainty_MOOC_Participants_2015On Monday, March 02, 2015 the web course “Estimation of Measurement Uncertainty in Chemical Analysis” was launched the second time as a MOOC (Massive Online Open Course).

The popularity of the course is this year somewhat higher than it was in 2014: more than 400 participants from 70 countries (ranging from Jamaica to Malaisia and from Zimbabwe to Finland) have registered (in 2014: 270 participants form more than 40 countries). Image on the left shows the countries where the participants come from. As in 2014, the majority of participants are from analytical laboratories, once again demonstrating the continuing need for training in measurement uncertainty estimation in analytical chemistry.

The full course material is accessible from the web page https://sisu.ut.ee/measurement/uncertainty. The course materials include videos, schemes, calculation files and numerous self-tests (among them also full-fledged measurement uncertainty calculation exercises). In order to pass the course the registered participants have to take six graded tests and get higher than 50% score. These tests are available to registered participants via the Moodle e-learning platform. Participants who successfully pass the course will get a certificate from University of Tartu.

It is planned to run this course as MOOC again in Spring 2016.

(Image: www.vidiani.com)

 

Dinesh_Indika_Dias_Defending_His_AMS_Master_ThesisOn Feb 20, 2014 AMS student Salgaduge Dinesh Indika Dias from Sri Lanka defended his master’s thesis titled Two-flow system for calibration of hygrometers at room temperature, supervised by research fellow Martin Vilbaste. This work has been performed in the framework of a broader research direction on metrology of air parameters, linked to the air humidity and air flow velocity reference laboratory at the UT Testing centre. The defence was very successful: Dinesh demonstrated his high competence in the field and the thesis was awarded the highest grade “A”.

Congratulations to you, Dinesh!

 

Leito_EACH_UMOOC_Malta_TC_MC_2015On Feb 06, 2015 at the annual meeting of the EURAMET Technical Committee of Measurements in Chemistry Ivo Leito made a presentation about the Measurement Uncertainty in Chemical Analysis Web Course and the EACH Erasmus Mundus Joint Master Degree Programme.

The registration to the Measurement Uncertainty Web Course is still open and as of now 240 participants from more than 30 countries (among them Uruguay, Bangladesh, Trinidad and Tobago, Mongolia, Honduras, etc) have registered. The course will run during Mar 02 to Apr 12, 2015. The main featurs of the EACH Erasmus Mundus Joint Master Degree Programme were explained. The presentation created intense discussions during the lunch break and several of the delegates were interested in collaboration with these activities.

 

 

Martin_Vilbaste_defending_his_PhD_DissertationOn Thursday, Jan 29, 2015 the defence of PhD thesis Uncertainty sources and analysis methods in realizing SI units of air humidity in Estonia prepared by Martin Vilbaste took place (photo on the left). The thesis is focused on several potential measurement uncertainty sources in air humidity measurement and on expressing the measurement results. Besides being important to metrology worldwide (as evidenced by a paper in the leading metrology journal Metrologia in the thesis), this thesis is very important for the Estonian national metrology infrastructure of air humidity in particular and more broadly – to the metrology of air parameters (temperature, humidity, air flow velocity).

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The defence was very successful. Martin Vilbaste is since several years the leading expert in air humidity measurements in Estonia (photo on the right presents him working with a climatic chamber) and the defence looked more like friendly discussion between experts.

Martin is routinely teaching metrology (both theory and practice) to Applied Measurement Science students. Our warm congratulatins to him!

 

 

The online course of Measurement Uncertainty Estimation in Analytical Chemistry (https://sisu.ut.ee/measurement/uncertainty/), which will be running as a MOOC during 02.03.15-12.04.15 couple of days ago got the 100th registered participant! The geographic diversity is wide: already now close to 30 countries are represented, among them Uruguay, Mongolia, Trinidad and Tobago, …

Registration will be open until Mar 02, 2015. Like in 2014, the course is free of charge also this year.

 

 

EACH_Webinar_Jan_2015On Jan 14, 2015 a Webinar took place for the EACH student candidates who either have submitted their applications or are in the process of preparing their application. The central aim of the webinar was to give a short overview of the EACH programme (the programme structure, the study tracks, the people, as well as the career possibilities after completing the programme) and the most frequent issues that we have been contacted with, as well as to answer any questions the Webinar participants may have. There were altogether 47 participants and a large number of questions were asked.

If you are interested in the webinar but were not able to participate, do not worry: the webinar has been recorded and can be watched at YouTube: https://www.youtube.com/watch?v=7tJJfypgXi0

The webinar slides are available from here: EACH Webinar Slides.

 

 

AMS_Seminar_Autumn_2014On December 14, 2014 the Applied Measurement Science autumn seminar took place. It was a long and intense day, full of very interesting measurement science. As a nice feature of the seminar, all the students currently studying in the AMS programme were present. So, on the left there is the picture of all the AMS students as of Dec 2014. Thank you, Illia, for this excellent picture!

As is typical for the AMS programme, the range of topics that students are investigating is very diverse. Just some examples:

  • Determination of 210Pb and 210Po with Liquid Scintillation Counting
  • Characterization of a graphene-based catalyst for oxygen electroreduction
  • Geological dating using ICP/MS
  • Screening of newborns for hereditary disorders using LC/MS
  • Metrological underpinning of calibration of hygrometers
  • Studying the light-harvesting process in photosynthesis
  • Validation of climatic chamber for high-accuracy thermal tests
  • Creating acidity scale in water-acetonitrile mixture

I take here the opportunity to express the best wishes for the New Year 2015 to all present, past and future students of AMS and EACH!

 

Sinai_Mwagomba_presenting is master_thesis_of AMS_at_University_of_TartuOn Dec 19, 2014 AMS student Sinai Mwagomba successfully defended his master’s thesis titled A method for thermal ambient tests of space technology equipment in a thermal chamber – development and validation (main supervisor: Riho Vendt PhD from Tartu Observatory). The aim of the thesis was to develop a method for thermal ambient testing of space equipment at Tartu Observatory, to validate it and to compile the measurement uncertainty budget.

The defence went very well: Sinai was able to confidently answer all the questions both from the opponent and the audience. The defence committee rated the thesis with the highest grade: “A”.

The work is one in the series of recent works carried out by AMS students in the framework of the space research programme launced at University of Tartu and Tartu Observatory, which recently made headlines with the launch of the EstCube-1 student satellite. The temperature regime is notoriously harsh for satellites orbiting the earth, with temperatures oscillating in the range of -100 °C to +100 °C, depending on whether the Sun shines on the satellite or is ecliped by the Earth. Thus, the main use of the developed method will be testing of space equipment before launching into the space. However, also many other fields (biochemistry, molecular biology, materials science) will benefit very much from rigorous temperature control and testing.

 

 

MSC_Euromaster_Graduation_Ceremony_2014On December 12, 2014 the Measurement Science in Chemistry Euromaster graduation ceremony took place in Brussels (Belgium) in the Royal Flemish Academy of Belgium for Science and the Arts. Altogether 46 students who participated in the MSC edition 2011, 2012 or 2013 received their Euromaster diploma supplements. The home universities of the students are University of Lisbon, Université Claude Bernard Lyon 1, University of Warsaw, Maria Curie-Skłodowska University, Adam Mickiewicz University, University of Tartu, University of Oulu, Vrije Universiteit Brussel and University of Maribor.

Tartu_Students_at_MSC_Euromaster_Graduation_Ceremony_2014

 

 

 

Six students from the University of Tartu AMS programme participated in the ceremony. In the photo on the right, bottom row: Hedi Sinijärv, Agnes Suu, Astrid Pung; top row: Yingjian Hou, Kristjan Haav, Sander Sannik.

We wish you all the success for your future endeavours in measurement science!

 

 

Measurement_Uncertainty_Course_Uncertainty_ConceptWe are glad to announce that the on-line course Estimation Measurement Uncertainty in Chemical Analysis will during the Spring semester 2015 be offered as a free on-line course (so called MOOC) to participants from all over the world. The course will be running during Mar 02 – Apr 12, 2015 and is open for registration.

The course gives the main concepts and mathematical apparatus of measurement uncertainty estimation and explains in detail two principal approaches to measurement uncertainty estimation – the ISO GUM modeling approach (the “bottom-up” approach) and the single-lab validation approach as implemented by Nordtest (the “top-down”) approach.

The course contains close to 50 short video lectures, schemes, practical examples, calculation files and numerous self-tests (among them also full-fledged measurement uncertainty calculation exercises). The full course material is accessible from the web page https://sisu.ut.ee/measurement/uncertainty.

During the online course period the online materials will be supplemented by discussion forum and possibility to ask questions from the teachers, as well as by tests and exercises that will be graded (and will jointly determine the final grade). The students who register to the course will be enrolled as guest students at UT and will eventually get one ECTS credit and a certificate form University of Tartu if they will successfully pass the course. In order to pass the course the registered participants have to take six graded tests and get higher than 50% score. These tests are available to registered participants via the Moodle e-learning platform.

This course can be used via web by anyone who wishes to improve the knowledge and skills in measurement uncertainty estimation.

 

EACH_JMD_Erasmus_plusThere are 23 scholarships available for the students admitted to the EACH programme (until Jan 31, 2015) and they are divided as follows: 13 scholarships funded by the EU (for partner country students and for programme country students) and 10 scholarships funded by the EACH consortium (tuition waiver scholarships). Please see the scholarships page for details what the scholarships cover.

The admission to the EACH Erasmus Mundus Joint Master Degree programme is open until January 31, 2015.

The online application form, admission requirements, deadlines, list of necessary documents, instructions/explanations, as well as contact data for questions are available from the EACH Admission information page.

This international two-year joint master degree programme educates specialists in analytical chemistry well qualified to work in industry (food, pharmaceutical, materials, energy, etc) and chemical analysis laboratories (environment, food, health, etc) worldwide. EACH provides knowledge and skills in both fundamental and applied aspects of modern analytical chemistry. Practical internship placement in industry or laboratories is an important part of the training. The programme is taught by four universities: University of Tartu (UT, coordinator), Estonia; Uppsala University (UU), Sweden; University Claude Bernard Lyon 1 (UCBL), France; and Åbo Akademi University (AAU), Finland. The language of instruction is English, but students will also learn to communicate in one of the languages of the countries involved.

 

Multivariate_FT-IR_quantitative_analysis_of_paints_and_coatingsDetermination of the composition of paints and coatings is important in many fields – materials science, art history, forensic science, etc. Fourier transform infrared spectroscopy (FT-IR spectroscopy) is a well-known method for the analysis of paints and coatings. However, the vast majority of work that has been carried out has been about qualitative analysis (i.e. just determinining what are the main components). Quantitative analysis has not been widespread, largely because of the very complex composition of most paints and coatings.

The master’s thesis of Pippa Hayes from the AMS programme has made an important conytribution to quantitative determination of composition of paints and coatings by FT-IR using the ATR (attenuated total reflectance) sampling. Her work demonstrates, using a wide selection of objects ranging from painting media to industrial coatings, that such quantitative analysis by FT-IR is feasible and she has carried out measurement uncertainty estimation of the results in order to assess their accuracy. As a proof of the quality of the work it has now been published in Spectrochimica Acta Part A 2014, 133, 207–213.

 

 

EACH_JMD_Erasmus_plusToday, on Oct 30, 2014 the admission was officially opened to the Excellence in Analytical Chemistry (EACH) Erasmus Mundus Joint Master Degree programme!

EACH is offered jointly by University of Tartu (Estonia), Uppsala University (Sweden), University Claude Bernard Lyon 1 (France) and Åbo Akademi University (Finland). The first study year is spent at Tartu studying the fundamentals in the framework of the AMS programme. The second year is specialization-oriented and is spent at one of the three partner universities.

The online application form, admission requirements, deadlines, list of necessary documents, instructions/explanations, as well as contact data for questions are available from the EACH Admission information page.

 

 

 

 

Retable of the high altar of the St. Nicholas' (Niguliste) Church in Tallinn

Retable of the high altar of the St. Nicholas’ (Niguliste) Church in Tallinn

On Oct 20-23, 2014 the investigation workshop “Rode Altarpiece in Close-up” took place in Tallinn (Niguliste church) and in Tartu (laboratories of UT Chemicum). It was conducted in the framework of a the project “History, Technical Investigation and Conservation of the Retable of the High Altar of Tallinn’s St. Nicholas’ Church
2013–2015” funded by the EU Regional Development Fund.

In Tallinn (20-21.10.14) the participants – conservation practitioners and students of art history and conservation – were given an overview of the practices and techniques of conservation science. Ivo Leito gave an overview of Analytical chemistry instruments and conservation research at UT Chemicum. an important part of the Tallinn session was taking small samples from the altar. In Tartu (22-23.10.14) the participants analysed the samples taken from the altar using the instruments available in Chemicum under the supervision of research fellow Signe Vahur.

The retable of the high altar of the St. Nicholas’ (Niguliste) Church in Tallinn is one of the most magnificent and best preserved northern German altar retables from the Late Middle Ages. The retable was made in the workshop of the well-known Lübeck master Hermen Rode in 1478. More than forty saints and biblical figures are depicted in the retable and it is among the largest retables from the 15th-century Hanseatic cities.

 

 

 

 

 

Leito_U_MOOC_NMKL_Eurachem_2014On Sept 30, 2014 Ivo Leito gave a presentation On-line course: Estimation of measurement uncertainty in chemical analysis
at the NMKL/Eurachem Workshop on Measurement Uncertainty.

The presentation outlined the contents and organisation of the material in the on-line course, the ways of using it (for independent learning, for self-testing, as an information source and as a basis for MOOC) and the experience of running it as a MOOC (Massive Open Online Course) in spring 2014. The presentation generated quite some questions and comments from the audience, both about the uncertainty estimation and didactical issues as well as about how the course was made.

The course material is available from https://sisu.ut.ee/measurement/

 

SAMSUNG CSCThe 2015 edition of the MSC Euromaster summer school will take place in Puławy (Poland) during Jul 11-25, 2015. Details can be found in the first circular.

Topics covered are:
· Traceability in chemical and bio-analytical measurements
· Validation of such measurement procedures
· Evaluation of measurement uncertainty in chemical measurements; uncertainty and compliance
· Statistics and statistical basis of calibration;
· ISO/IEC-17025 standard quality system and laboratory assessment;

Teaching methods: Problem based learning is at the heart of the school. There are lectures, but project work, case studies and assignments carry most weight. Throughout the summer school, students work in small teams to tackle the various challenges which they will be given. Each team needs to set up an independent analytical laboratory to perform service analysis for a customer.

The MSC Consortium has been fostered by the European Commission Joint Research Centre, in view of the importance of laboratory accreditation in European legislation and external trade. In 2007, the JRC was instrumental in bringing together a consortium of universities offering an international master programme in Measurement Science in Chemistry (www.msc-euromaster.eu), which received a Euromaster® quality label in 2008 (renewed in 2013).

(Image on the left: students working in the MSC Summer School 2013)

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Today the introductory meeting of the AMS students with the programme coordinator took place. An overview of the programme was given (the slides are available from here) and the questions of the students were answered, followed by a joint lunch and tea/coffee/chatting.

There were 13 students (originating from Portugal, India, Latvia, Nigeria, Greece, Germany, Ghana, Estonia, Ukraine and China) participating (and some more are still on their way to Estonia). This number of students starting their studies in AMS this year is the biggest of all time.

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On Friday, Aug 29, 2014 the defence of PhD thesis Acidity and basicity in non-aqueous media: importance of solvent properties and purity prepared by Karl Kaupmees took place.

Karl’s thesis is focused on solvent characteristics, that influence the pKa measurements
in non-aqueous media and is divided into two major sections. In the first part, pKa
measurements for two sets of compounds – pKa of chiral strongly acidic catalysts (e.g. the BINOL, NTPA and JINGLE families) and pKa of fluoro- and chloro-substituted phosphanes are carried out revealing the importance of knowledge of solvent properties in order to achieve accurate and reliable results. In collaboration with our partner research groups it was also discovered that the acidities of the involved compounds have strong impact on the respective catalytic processes.

In the second part of the thesis, the influence of water, at low concentration, below 1% (w/w), is systematically studied on the relative acidities and basicities. It is quantitatively shown, that acids are much more influenced by the increase of water content in solvent, compared to bases. Higher impacts are observed in case of acids and bases with localized charges in corresponding ions.

In order to quantify the charge delocalization in ions, for the first time, two computational parameters WAPS (charge delocalization parameter for anions) and WANS (charge delocalization parameter for cations) are proposed. The strength of the acids as well as the nature of acidity center are shown to affect the changes in relative acidity upon increase of water content. Recently it has also been discovered that there is a good correlation between the WAPS charge delocalization parameter and the electrospray (ESI) ionization efficiency of the compounds.

The defence was very successful and it is expected that the results will be of interest to a wide community of chemists and technologists.

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On Friday, Aug 29, 2014 the defence of PhD thesis Novel Tools for Water Quality Monitoring – From Field to Laboratory prepared by Teemu Näykki took place. Teemu Näykki works as team leader at the Finnish Environment Institute (SYKE). The thesis introduces a set of new tools for water quality monitoring. These include:

The defence was very successful and the results are expected to be of significant help to field laboratories in assuring and improving the quality of their chemical analysis results for water monitoring.

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UT Chemicum

On Monday, September 1, 2014 starting at 12:15 the introductory meeting of the Applied Measurement Students with the programme director will take place in UT Chemicum (Ravila 14a) in room 1100. Although the meeting is primarily for the first year students just starting their studies, the second year students are also welcome.

Overview of the programme structure will be given, together with the requirements of acquired ECTS credits per semester. The courses – both obligatory and elective – will be briefly introduced, as well as the AMS timetable of this semester. The people who will be taking care of the different aspects of your study life in Tartu will be introduced. This meeting is also meant for asking any questions related to the Applied Measurement Science study programme and organisation of your studies, as well as general topics if some unanswered questions remained from the main orientation course.

This map of Tartu, featuring (almost) all University buildings will help you to find Chemicum (see page 2). The suitable bus is No 3 (stop Tehnoloogiainstituut or Nooruse). The picture above shows what Chemicum looks like. It is very easy to find from the bus stop.

If there are any problems with reaching the place, please call me: +372 5 184 176.

I am looking forward to meet you on 01.09.2014!

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On Friday, August 8, 2014 the MSC Euromaster Summer School 2014 finished. This year’s summer school took place in Casablanca (Morocco) and was hosted by the ESITH educational centre. Around fourty students from ten countries participated.

As in previous years, a key activity of the summer school was the contest of student teams, which tested their knowledge and skills in almost all areas of metrology in chemistry. This year the summer school advanced further in terms of shiftin the activities away from the classical lecture-type of teaching by incresing the share of discussions, hands-on work, teamwork.

Three AMS students from UT – Dinesh Indika Dias, Illia Shypunov, Sinai Mwagomba – also participated and their impressions are very positive.

Dinesh: “It was a great experiance, two weeks living in and concentrated on one subject. most imortantly now we are members of large network in Chemical measurement. I am very happy to say that at the Examination I maneged to get 10 out 10 and It was the best result of this summer school.”

Illia: “I found all exercises really useful from all aspects, it gives huge amount of practical information and skills that we can implement in future laboratory work. So I am enjoing, also Morocco is interesting country with specific colorful culture”.

Sinai: “The experience at Summer school is awesome! And it ties together all we learn in our curriculum. Our performance was really good as all of us got good grades in the exam.”

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The EU EACEA has made the decision to select for funding the Erasmus+ (formerly known as Erasmus Mundus) International Joint Master Degree (JMD) programme Excellence in Analytical CHemistry (EACH), which will be launched in 2015 by a consortium led by the University of Tartu.

The Erasmus+ JMD (formerly known as Erasmus Mundus) is a scheme of Joint European study programmes aiming to include the best that Europe has to offer in higher education. The scheme is prestigious and therefore highly competitive: the success of the EACH programme this year came after three preceding proposals were turned down.

The EACH programme will be   delivered by 4 full partners – University of Tartu, Uppsala University (UU), University Claude Bernard Lyon 1 (UCBL) and Åbo Akademi University (AAU) – as well as 26 associated partners – industries, laboratories and universities. The associated university partners are from Europe, Asia and North America.

Student mobility is an essential part of the programme. The study tracks are pictured in the image on the left. The students spend their first study year at UT learning the fundamentals of analytical chemistry (including the mainstream practical skills for working in an analytical laboratory), analytical quality and metrology in chemistry as well as the socio-economic aspects of analytical chemistry. This will be done on the basis of the modules of the Applied Measurement Science programme. The second study year is specialisation-oriented and is spent either at UU, UCBL or AAU. Each of these universities is strong in one of the branches of applied analytical chemistry:
– UU: Organic and bio-analysis, separation methods and mass spectrometry, especially as applied to biological objects.
– UCBL: Industrial analytical chemistry and process control.
– AAU: Electrochemical sensors, electroanalytical chemistry, advanced analytical devices.

The studies are made more real-life oriented by internship placement in an industry or a laboratory. In order to teach advanced and frontier topics of analytical chemistry the programme includes a winter school, where such topics are lectured by invited scholars from associated partners and other institutions.

Please see the EACH Website for more information.
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Joint Choirs Performing at Laulupidu Song Festival

During July 05-07, 2014 the XXVI Laulupidu (Song Festival) and XIX Tantsupidu (Dance Festival) took place in Tallinn, Estonia, attracting altogether more than 150 000 people. Such festivals are organized every 5 years and the first Song Festival took place in 1869. This time the title of the festival was “Touched by Time. The Time to Touch” and it travelled musically through the Estonian choir song tradition from the 19th century to the present.

Laulupidu takes place at Lauluväljak (Song Festival grounds, photo on the left), featuring a gigantic stage specifically designed for singing by huge choirs of thousands of people. The stage features an arc-like roof, which also acts as a sound box helping to direct the music towards listeners.

Song Festival Procession

Laulupidu starts with a procession lasting for several hours where the participants walk through the streets of Tallinn to the Song Festival grounds. The songs performed have been written by Estonian composers and some of them have become extremely popular and are performed at every Laulupidu, e.g. Mu Isamaa on minu arm (My Fatherland, my love), Põhjamaa (A land in the north), Ta lendab mesipuu poole (Flying towards the beehive). Different songs are performed by different choirs (children’s choirs, Male choirs, Female choirs, Mixed choirs). More than 900 individual choirs participated. In order to be admitted as performers to Laulupidu, all choirs had to pass a stringent selection process.

Boys Singing at the Song Festival

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The culmination of the event is traditionally in the end of the second day when the so-called joint choir sings the choir songs most loved in Estonia. This time more than 20 000 singers were singing, conducted by the best Estonian choir conductors and supported by tens of thousands of listeners who were singing along. The overall number of people on the Song Festival grounds during the joint singing was around 100 000. The number of individual choirs that participated in that singing was beyond 600.

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Song Festival Listeners (who also sing!)

Such joint singing is extremely emotional and is much, very much, more than just songs performed by numerous singers. When participants are asked about their feelings then usually they find it impossible to put in words the overwhelming feeling happiness, joy, solidarity between people, etc. Many people are almost weeping when singing. Laulupidu is certainly the most powerful force uniting Estonian people (who otherwise are notorious for their individualism) and for many people the highest and purest form of expressing the identity of Estonians as a nation. The video below gives an example of joint singing from this Laulupidu.

Throughout the Estonian history the Song Festival tradition has been decisively important in the formation of Estonians as a nation, in the birth of the first Estonian republic in 1918 and, especially, in regaining the independence in 1991, via the so-called “Singing revolution”.

All this put together makes Laulupidu by far the most important and impressive cultural event that can be experienced in Estonia. Laulupidu has been included in the UNESCO’s List of the Intangible Cultural Heritage of Humanity.


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On April 23, 2014 the in situ Interlaboratory comparison measurement (ILC) of dissolved oxygen concentration Fieldoxy 2014, organised jointly by the Finnish Environmental Institute (SYKE) and University of Tartu (UT) took place in the Gulf of Finland, on board of SYKE’s research vessel Aranda. The intercomparison was organised in the framework of the EMRP ENV05 Ocean project funded within the framework of the European Metrology Research Programme (EMRP). There were altogether 20 participants from 10 research institutes from 5 countries (Finland, Estonia, Sweden, France, Germany).

The role of University of Tartu in the intercomparison was to provide reliable reference values for the intercomparison, against which the results of the participants could be assessed. This was done using the modified highly accurate Winkler titration procedure developed previously at UT in the framework of the same project. The main modification were (1) using high-precision piston burette instead of weighing (it is not possible to accurately weigh on a ship) and (2) taking into account the uncertainty due to possible oxidizing or reducing impurities ion the seawater. In addition to the measurement uncertainty sources intrinsic in the procedure, the uncertainty due to spatial inhomogeneity of seawater around the rosette sampler (see presentation slides) was taken into account. This uncertainty contribution was found to be very important (it was the dominant uncertainty source at two immersion depths out of three).

On June 16, 2014 the coordinator from SYKE, Teemu Näykki, made a presentation on the preliminary results of the Fieldoxy 2014 intercomparison at the project meeting of ENV 05. The results show good agreement between the results of the participants and the reference values. In particular, and very importantly, there was no bias evident between the reference values and the participant results.

For comprehensive results of the intercomparison please see the final report of the Fieldoxy 2014 intercomparison.

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Organization of this intercomparison has been partly funded by the European Metrology Research Programme (EMRP), project ENV05 “Metrology for ocean salinity and acidity”. The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union.

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Five AMS master’s students successfully defended their theses today (on June 9, 2014). On picture, from left: Petrică Artene, Roland Hoxha, Kaspars Laizans, Astrid Pung and Shanshan Wu (Ivo Leito is standing between Kaspars and Astrid).

Traditionally for AMS the topics of the theses were diverse ranging from artificial photosynthesis to measurements in biochemistry and from synthetic molecular receptors to quality assurance in vibration testing.

Congratulations to all of you!

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Today on Jun 6, 2014 a webinar was held for the student candidates admitted to teh Applied Measurement Science programme starting for the 2014/2015 study year. 16 prospective students participated. Short presentations were given by Ivo Leito (slides available here) and Kaija Murasov from the UT International Student Service. AMS student Janis Linitis shared his experience of life and studies at Tartu.

We hope to meet all the participants in Tartu in Autumn!

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On May 17, 2014 the spring seminar of the Applied Measurement Science programme took place. Students presented and discussed the progress of their master’s theses.

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As is usual for the AMS programme, a very wide range of topics is investigated by our students. Just some examples:

— Determination of Pb-210 and Po-210 isotopes in ash using liquid scintilation counting
— Testing of electronics components for their stability against vibration
— Studying artificial photosynthesis
— Calibration and testing system for air humidity measurements
— Computational modeling of synthetic receptors for small anions
— Characterization of space technology equipment for stability towards exptreme temperatures
— Catalysis studies for oxygen electroreduction
— Measurements of thin film properties

After the seminar the students had a small picnic/barbeque.

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During May 19-21, 2014 the Eurachem Workshop on Quality in Analytical Measurements is taking place in Lisbon (Portugal). The workshop covers all main issues in ensuring the quality of analytical results, ranging from traceability to validation and from measurement uncertainty to routine quality assurance in laboratories.

Ivo Leito from University of Tartu participated in the session dedicated to bias evaluation and proficiency testing. He initiated and moderated a discussion around the issues in evaluation of bias/recovery. The discussion slides are available from here. The slides are composed so that they have questions and blanks and these questions are answered and blanks are filled in with the help of the audience.

You are welcome to test your understanding of the bias issues by trying to fill in the blanks and answer the questions. You can then test your understanding by downloading the slides with answers solutions. Please contact Ivo Leito if you have any questions.

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On Apr 16, 2014 the MOOC Estimation of measurement uncertainty in chemical analysis offered by University of tartu finished successfully. The course eventually had 270 participants from more than 40 countries. 141 participants successfully completed the course, making the completion rate 52%, which is very good for a MOOC, especially one that has quite difficult calculation exercises, which need to be done correctly for completing the course. Comparing to other MOOCs: completion rates around 10% and below are actually quite common with MOOCs as indicated by a recent survey).

The feedback was very positive (some examples) and we are glad that evidently we were able to offer something that is really needed by people who do chemical analysis in their everyday work, as many of our participants. The participants were very active and asked lots of questions. These were often very much to the point and addressed things that are really important to analysts in their everyday work. The course had several forums (general and by topic) and the overall number of posts to them during the course period reached beyond 300! (overall number containing posts from participants and teachers)

This active participation made teaching this MOOC a great experience also for us, the teachers. The discussion threads gave a lot of added value to the course and some of them triggered making important modifications to the course materials.

We plan to repeat this course again in Spring 2015.

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On Monday, March 03, 2014 the web course “Estimation of Measurement Uncertainty in Chemical Analysis” was launched as a MOOC (Massive Online Open Course). This is the first MOOC created at University of Tartu.

The course has turned out to be very popular – more than 260 participants from more than 40 countries (ranging from Nicaragua to Iceland and from USA to Singapur) have registered. Image on the left shows the countries where the participants come from. The majority of participants are from analytical laboratories. This demonstrates the continuing need for training in measurement uncertainty estimation in analytical chemistry.

The full course material is accessible from the web page https://sisu.ut.ee/measurement/uncertainty. The course materials include videos, schemes, calculation files and numerous self-tests (among them also full-fledged measurement uncertainty calculation exercises). In order to pass the course the registered participants have to take six graded tests and get higher than 50% score. These tests are available to registered participants via the Moodle e-learning platform. Participants who successfully pass the course will get a certificate from University of Tartu.

It is planned to run this course as MOOC again in Spring 2015.

(Image: www.vidiani.com)

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The online course of Measurement Uncertainty Estimation in Analytical Chemistry (http://sisu.ut.ee/measurement/), which will be running as a MOOC during 03.03.14-13.04.14 has this morning got the 100th registered participant. The geographic diversity is wide: all six inhabited continents are represented!

Registration will be open until Mar 02, 2014.

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Different chiral 1,1’-bi-2-naphthol (BINOL)-derived acids and their analogues (see image on the right) were recently introduced as a highly efficient class of metal-free Brønsted acid organocatalysts, capable also of enantioselective (chiral) catalysis.


These catalysts have been successfully used for a wide range of reactions (hydrogenations, various addition reactions to aldimines and ketimines, Diels-Alder and [3+2] cycloaddition reactions, Nazarov cyclizations, asymmetric protonations, Mukaiyama aldol reactions, etc). In spite of their wide usage, accurate data about their acidity were not available until recently.

PhD student Karl Kaupmees (image on the left) has carried out measurement of pKa values of a number of those acids in acetonitrile and as a result, reliable acidity data are now available. Furthermore, it was possible to demonstrate for the first time that the catalytic activity of the acid in one of the reactions (Nazarov cyclization) is directly related to the acidity of the acid catalyst.

This result was so significant that it was published by one of the most prominent chemistry journals Angewandte Chemie Int. Ed. (Angew. Chem. Int. Ed. 2013, 52, 11569-11572).

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We are glad to announce that the on-line course Estimation Measurement Uncertainty in Chemical Analysis will during the Spring semester 2014 be offered as a free on-line course (so called MOOC) to students from all over the world. The course will be running during Mar 03 – Apr 13, 2014 and is now open for registration.

During online course period the online materials will be supplemented by discussion forum and possibility to ask questions from the teachers, as well as by tests and exercises that will be graded (and will jointly determine the final grade). The students who register to the course will be enrolled as guest students at UT and will eventually get one ECTS credit and a certificate form University of Tartu if they will successfully pass the course.

The course gives the main concepts and mathematical apparatus of measurement uncertainty estimation and explains in detail two principal approaches to measurement uncertainty estimation – the ISO GUM modeling approach (the “bottom-up” approach) and the single-lab validation approach as implemented by Nordtest (the “top-down”) approach. The course contains close to 50 short video lectures, practical examples and numerous tests and exercises for self-testing. This course can be used via web by anyone who wishes to improve the knowledge and skills in measurement uncertainty estimation.

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On Dec 27, 2013 Postimees, a prominent Estonian Daily newspaper, has awarded its annual title “person of the year 2013” to Mart Noorma – the initiator and scientific mentor of the Student satellite project ESTCube-1. This title is each year awarded by Postimees to a person who has during the year accomplished something significant, with impact expected to last for years to come.

ESTCube-1 is the first Estonian satellite. It was built by students from University of Tartu in collaboration with Estonian Aviation Academy, Tallinn University of Technology and Estonian University of Life Sciences, as well as participants from abroad. The main goal of the satellite is testing the so-called solar sail concept. The satellite was successfully launched on May 7, 2013. The solar sail experiment is planned to be carried out in 2014. Successful lauch of the satellite brings Estonia into the family of space states and marks the beginning of a new era in Estonian space technology. A next satellite – ESTCube-2 – is already in planning (in the framework of the QB50 project for ionosphere measurements).

The ESTCube satellite project has strong links also with the Applied Measurement Science master’s programme: three students of the programme work or have worked in the ESTCube-1 project: Kaspars Laizans, Martynas Pelakauskas and Mykola Tverdokhlib.

Mart Noorma works as senior lecturer of optical metrology and as vice-dean of studies at Faculty of Science and Technology, University of Tartu. He is the leader of the space technology group at University of Tartu. He is also well known for introducing innovative teaching approaches at University of Tartu and for his wide-ranging activities as popularizer of science.

(Photo: Peeter Langovits, Postimees)

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On Nov 7, 2013 Ivo Leito gave presentation titled Measurement Science in Chemistry Education at University of Tartu in Opatija (Croatia) at the conference “Laboratory Competence 2013” organized by CroLab – the Croatian Association of Laboratories. The presentation contains information about the Applied Measurement Science master’s programme et University of Tartu, about the international consortium of master’s programmes Measurement Science in Chemistry and about the recently launched on-line course Estimation of Measurement Uncertainty in Chemical Analysis.

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On Oct 24, 2013 a seminar “Quality assurance and validation of analytical methods in the laboratory” was organized jointly in helsinki by the Finnish Chromatography society and Finnish Mass spectrometry society. Ivo Leito from University of Tartu made a presentation on the approaches to measurement uncertainty estimation. The presentation compared the ISO GUM modelling and the Nordtest approach to measurement uncertainty estimation. The Nordtest approach was explained in more detail and an application example – measurement uncertainty in LC-MS analysis (determination of acrylamide in snacks by LC-MS) – was discussed. The online course of measurement uncertainty estimation in analytical chemistry that was recently set up at University of Tartu was briefly introduced.

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We are glad to introduce the Online Course of Measurement Uncertainty Estimation in Analytical Chemistry!

It has been set up at University of Tartu during 2013 and its version 1 is now accessible from the address
http://sisu.ut.ee/measurement/. This is an introductory course on estimation of measurement uncertainty, specifically related to chemical analysis. The course gives the main concepts and mathematical apparatus of measurement uncertainty estimation and explains in detail two principal approaches to measurement uncertainty estimation – the ISO GUM modeling approach (the “bottom-up” approach) and the single-lab validation approach as implemented by Nordtest (the “top-down”) approach. The course contains close to 50 short video lectures, practical examples and numerous tests and exercises for self-testing.

In spite of being introductory, the course intends to offer sufficient knowledge and skills for carrying out uncertainty estimation for the common analyses in routine laboratory environment. The examples or exercises currently include measurement uncertainty in acid-base titration, measurement uncertainty in Kjeldahl nitrogen determination, measurement uncertainty in UV-Vis spectrophotometry, measurement uncertainty in atomic absorption spectroscopy and measurement uncertainty in liquid chromatography mass spectrometry (LC-MS) and more is coming. It is important to stress, however, that for successful measurement uncertainty estimation experience (both in analytical chemistry as such and also in uncertainty estimation) is crucial and this can be acquired only through practice.

This course can be used via web by anyone who wishes to improve the knowledge and skills in measurement uncertainty estimation. It will also be offered as a registered (i.e. giving credit points) free online course (interfaced with the Moodle study environment) starting from Spring semester of 2014 as to students from all over the world.

Needless to say, all feedback is most welcome!

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On Jun 28, 2013 the Report on method for improved gravimetric Winkler titration (by Irja Helm, Lauri Jalukse, Ivo Leito) has been published by University of Tartu in the framework of the European Metrology Research Programme (EMRP), project ENV05 “Metrology for ocean salinity and acidity”. Full text of the report is available from here. This report is based on the doctoral dissertation of Irja Helm and on the recent publication I. Helm, L. Jalukse, I. Leito “A highly accurate method for determination of dissolved oxygen: Gravimetric Winkler method” Analytica Chimica Acta 2012, 741, 21– 31. It is expected to be useful laboratory guide in all sectors (environmental, energy, materials, …) where reliable measurements of dissolved oxygen concentration are needed.

This work has been partly funded by the European Metrology Research Programme (EMRP), project ENV05 “Metrology for ocean salinity and acidity”. The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union.

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The research work on accurate measurement method of binding constants in supramolecular chemistry carried out by Kristjan Haav (left) in the framework of his AMS master’s thesis has gained international recognition: it has been published by the Journal of Organic Chemistry, one of the most prominent organic chemistry journals: Accurate Method To Quantify Binding in Supramolecular Chemistry K. Haav, S. A. Kadam et. al. J. Org. Chem. 2013, 78, 7796−7808.

Measurement of host-guest binding constants is one of the pillars of supramolecular chemistry and is indispensable for designing smart materials, chemo-sensors, etc. Up to now such measurements are typically made by methods that give absolute binding constant values, but at the same time suffer from serious systematic effects making comparison of data from different research groups very difficult.

Kristjan has developed an approach for accurate and comparable measurement of host-guest binding affinities whereby differences in binding strength (ΔlogKass values) are measured between two host molecules toward a particular guest under identical solvent conditions. Measuring differences instead of absolute values enables obtaining highly accurate results, because many of the uncertainty sources (the solvation/association state of the guest in solution, deviations in solvent composition, etc.) cancel out. As a proof of concept, this method was applied to the measurement of the binding strength of 28 synthetic anion receptors toward acetate in acetonitrile containing 0.5% water. The receptors included differently substituted indolocarbazoles, ureas, thioureas, and some others. A self-consistent (consistency standard deviation 0.04 log units) binding affinity scale (right) ranging for around 2.7 log units was constructed from the results.

This work – published in an organic chemistry journal and belonging to the field of supramolecular chemistry – is a nice demonstration of the ubiquity of importance of reliable measurements.

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On Friday, Aug 30, 2013, the introductory meeting for first-year AMS students was held. Sergei Jurtšenko gave overview of the AMS programme, timetable of autumn semester 2013 and some practical aspects of studying in Tartu. The PDF file of this presentation is available for download from here.

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Roland Hoxha (in the middle on the photo), an AMS student who participated in the Measurement Science in Chemistry (MSC) Summer shool 2013 in Lyon said the following about this experience:

“Summer school was really a great experience for me. Meeting new friends, sharing knowledge between each other, playing games, visiting marvelous places and furthermore learning chemistry. Even though Measurement science in chemistry (MSC) at Tartu University is a completed program in metrology in chemistry, summer school decorated it with its surprises by teaching new things in a quite interesting and amusing way. I really consider myself lucky for participating in MSC summer school. I wish that every student who study metrology in chemistry to try it.”

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Shanshan Wu (third from left on the photo), an AMS student who participated in the Measurement Science in Chemistry (MSC) Summer shool 2013 in Lyon said the following about this experience:

“This is an unforgettable Summer I never had before, full of new things and challenges. This Summer school not only let me enhance my knowledge and skills but also broaden my views. Thank you for everyone who offered me this chance to take part in it!”.

The next MSC Summer school is scheduled to take place in Pulawy (Poland) in Summer 2014. All students enrolled in the Applied Measurement Science programme are eligible for applying for membership in the MSC consortium and in the Summer school.

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On Friday, Jul 12, 2013 the MSC Summer school visited the Alps and ascended from Chamonix to a nearby mountain – Aiguille du Midi – with the height of slightly over 3800 m. This is a big advancement from the previous “MSC Summer school record” – Mount Moussala, the highest top of Balkans at 2925 m – which was conquered during the 2009 MSC Summer school.

The picture on the left gives some impressions from Aiguille du Midi. The highest top on the picture (the white round one on the right) is the Mont Blanc. In addition to enjoying the fantastic views and a walk in the mountains, numerous water samples were collected by the students. Those water samples will be analysed in the coming week and compared to the ones taken from various places in Lyon.

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Two young scientists – Karin Kipper and Riin Rebane – from UT analytical chemistry research group participated in the recent HPLC2013 conference in Amsterdam. Both of them presented the most recent results of their work.

The presentation of Karin Kipper (left) titled “Simultaneous Analysis of Carbapenems in Human Bodily Liquids Using HFIP as Buffer Additive in LC-ESI-MS/MS” focuses on the use of 1,1,1,3,3,3-hexafluoroisopropanol (HFIP) as a weak volatile buffer acid for creating LC/ESI/MS mobile phases in the basic range (pH = 8 .. 10). It is not easy to find a good buffering system in this pH region that would at the same time be LC/MS compatible, that is, volatile and not suppressing inonization. HFIP, when mixed with ammonia, offers such possibility. Besides providing suitable buffering capacity at high pH HFIP as mobile phase component also increases the retention of compounds poorly retained on the C18 mobile phase and improves peak shape.

Riin Rebane (right) in her presentation “Method development strategy for derivatization LC/ESI/MS” explores the derivatizing agents for amino acids for LC/ESI/MS analysis. Amino acids generally cannot be analyzed by LC/ESI/MS without derivatization, because they are highly polar (zwitterionic) compounds and (1) are poorly separated on most stationary phases and (2) are (paradoxically!) poorly ionized in the ESI ion source. Riin has explored both classical (Fmoc-Cl, DNS, DEEMM) and novel (TAHS, FOSF) derivatization reagents. She discovered that the novel derivatization reagents proved to be more sensitive and the FOSF reagent (developed ans synthesized in her work) offered better chromatographic separation than TAHS. Moreover, with careful method development towards LC/ESI/MS analysis, classical reagent DEEMM can provide comparable detection to novel reagents with advantages such as good chromatographic separation and wide linear range.

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On July 08, 2013 the sixth MSC Euromaster Summer School 2013 started in Lyon (France). Altogether 34 students from more than ten countries participate in the Summer school, among them three students from the AMS programme of University of Tartu: Astrid Pung, Shanshan Wu and Roland Hoxha. The activities in the summer school put large emphasis on interactive learning, problem solving and team work. Please see the MSC Consortium website for more information.

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On Jun 17, 2013 The kick-off meeting of the EMRP project Metrology for Moisture in Materials (SIB64 METefnet) took place in MIKES (Helsinki).

Around 70% of industries use drying at some stage of their production process. Active ingredients in pharmaceuticals, carbon-fibre composites, polymers, food powders, novel cellulose-based active paper, biomass and in many other solid materials are highly affected by moisture when processing into various products. Errors and inconsistencies in moisture measurement and control in industrial processes lead to decreased process speed/throughput and increased wastage, shortened durability of biomaterials, increased energy consumption in drying and increased fine particle emissions in biomass combustion.

Currently more than 1300 national or international documentary standards are in active use because available measurement methods, reference methods and even the current definitions for moisture as a measurand are material specific. Moisture also is a tricky parameter to measure – moisture is everywhere around us, water can be bound in materials with different strength, etc. These effects escalate in calibrations of moisture analysers with reference samples. The measurement uncertainty is usually substantial, but in many cases unknown.

This international project – SIB64 METefnet – with partners from Finland, UK, Estonia, France, Romania, Czech, Italy, Denmark, Turkey and Slovenia aims at a radical movement away from the standards/procedures-based metrology and towards improved dissemination of SI traceability to moisture measurements in industry by removing ambiguities and inconsistencies in moisture measurement and calibration techniques. This will be achieved through development of new more relevant and effective methods of realising and disseminating SI units of moisture and provision of metrology infrastructure for moisture measurements.

University of Tartu participates in METefnet and is responsible for setting up high-level primary coulometric KF titration measurement method of moisture in different materials.

The full summary of the project can be seen at its (still embryonic) website: http://www.metef.net/
The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union.

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Ten AMS master’s students successfully defended their theses today (on June 10, 2013). On picture, from left: Hedi Sinijärv, Sander Sannik, Karen Atabekjan, Yingjian Hou, Kristjan Haav, Kamarniso Vrandecic, Pippa Hayes, Agnes Ivanov, Galyna Gryliuk, Agnes Suu.

Traditionally for AMS the topics of the theses were diverse ranging from nuclear energetics to measurements in biochemistry and from synthetic molecylar receptors to redefining the concept of pH.

Congratulations to all of you!

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Definitions of the International vocabulary of metrology (VIM 3) are the foundation of the language spoken by measurement people. The definitions have been carefully elaborated with the involvementof a number of top experts. Nevertheless, if a near-perfect definition is aimed at then it often happens that the definition becomes complex and loses its simplicity. So, some of the definitions need additional explanations to be fully understood, especially by students and people at routine laboratories. One of these is the VIM definition of calibration, especially if it is to be applied to the instrumental chemical analysis.

I tried to make a small contribution towards better general understanding of this definition and now a small video explaining the VIM 3 definition of calibration as applied in chemical analysis using instrumental methods (actually an eleven minute excerpt of a longer lecture) is available at YouTube. Any feedback is welcome!

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The ESTCube-1 satellite was successfully launched early in the morning of 07.05.2013! Some hours later on the same day it was officially announced that the satellite works. Three AMS students (Kaspars Laizans, Martynas Pelakauskas, Mykola Tverdokhlib) are participating or have participated in the project. See more at the ESTCube-1 Facebook page.

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Hydrogen bond (HB) is by its importance a unique chemical phenomenon in nature and has been widely studied from almost any possible viewpoint. HBs have an enormous role in the structure (proteins, nucleic acids, cellulose fibers, etc) and functionality (enzyme catalysis, ligand-receptor complexes, etc) of all forms of life as well as a countless number of supramolecular systems. Computational prediction of HB is of high interest both for rationalizing existing and developing new chemical and biochemical systems and processes. A comprehensive study of modeling HB with the COSMO-RS computational method has been recently carried out at UT Chair of analytical chemistry (ChemPhysChem, 2013, 14). The method displayed mixed behavior, being quite successful with some systems but failing with others.

Q: What is the connection here with measurements?
A: A direct one. The level of success of the computations was assessed by comparison with measurement results of hydrogen bond formation equilibrium constants. And, surprisingly, it turned out that a large part of data on HB formation constants in the literature was unusable because of inconsistrencies and lack of any information characterizing the uncertainty of the values. The values from different groups sometimes varied by up to an order of magnitude (!). Such doubtful datasets of course were left aside when carrying out the evaluation.

This work nicely proves the importance of good measurement science also for theoretical chemistry: it is not possible to develop and improve theoretical computation methods if teh obtained results cannot be compared to accurate measurement results.

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An important direction in making measurement instruments is making them simpler, cheaper and accessible to many people. An interesting development in this direction has been made at SYKE (the Finland Environmental Administration): the Secchi3000 Turbidity analyser, in which a standard mobile phone camera serves as the measurement instrument.

Secchi3000 was developed to be a low cost and simple operation tool for water quality measurements. The objective was to offer it also for non-experts and citizens interested in water quality issues. Performing measurement with Secchi 3000 is simple: The user fills the Secchi3000 container with water from a lake, river or sea, places the measurement structure in the container and takes a photograph with a mobile phone through a hole in the lid of the device (Figure on the right). The photograph is taken with an application called EnviObserver (developed by VTT, Finland). The application sends the photograph to a server together with metadata such as the location of the measurement. At the server the photograph is analysed with an algorithm, which finds the target areas from the picture and computes water quality parameters based on the brightness values of the target areas. Finally, the results are sent back to the user’s mobile phone and stored in data bases.

For more information please download the poster about the Secchi3000 water turbidity analyser.

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During 17-22.02.2013 The first Analytical Chemistry Winter school “Novel analysis methods”, organized by the St. Petersburg’s State University, took place near St. Petersburg (Russia). Ivo Leito participated in the event and gave a short lecture about Liquid chromatography tandem mass spectrometry with the electrospray ion source (LC-ESI-MS/MS) as a tool in trace contaminant analysis. The lecture presented the difficulties in connecting LC to MS, described electrospray (ESI) ion source as the most widely used intrerface for connecting LC and MS, briefly explained the multidimensional information obtainable from LC-MS experiment and finally reviewed the benefits of tandem mass spectrometry (MSMS or MS2) detection in trace contaminant analysis as opposed to simple MS detection.

As real-life examples of using liquid chromatography tandem mass spectrometry in analysis of traces of contaminants and bioactive compounds, see for example the following:
Determination of pesticide glyphosate in cereals LC-ESI-MSMS (Rapid Commun. Mass Spectrom. 2011, 25, 3252–3258)
Analysis of seleno amino acids selenomethylselenocysteine and selenomethionine by LC-ESI-MS/MS with diethyl ethoxymethylenemalonate derivatization (Analyst 2011, 136, 5241-5246)
Analysis of five pesticides (methomyl, thiabendazole, aldicarb, imazalil, methiocarb) in five fruit/vegetable matrices (tomato, cucumber, apple, rye and garlic) using LC/MSMS with electrospray ionization (Analytica Chimica Acta 2009, 651, 75–80)

Ivo Leito also gave a short overview of the Applied Measurement Science programme.

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Amer Jamil Aref Al-Malahmeh from Jordan successfully defended his master thesis on January 15, 2013. The title of the thesis was “Methodological development and validation of Sample treatment and Source preparation procedures and Liquid Scintillation counting measurements for Determination of 226Ra in Drinking water”. 226Ra is a potentially dangerous radionuclide for people using ground water as drinking water. A large number of different influencing factors were tested and evaluated in the thesis and a serious uncertainty budget was compiled, which can be of high interest to scientists working in the area of radionuclide determination. The thesis is remarkable also because it was defended four months (!) in advance of the deadline.

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On Saturday, Dec 15, 2012, the Autumn semester master’s seminar 2012 of the AMS programme was concluded with presentations from students.

Most of the presentations were based on the master’s thesis topics of our students. As is typical for our interdisciplinary programme, the topics were diverse, ranging from determination of radium in water to artificial molecular receptors, from universal pH scale to building a student satellite. Here is a short (and not exhaustive) list of the areas in which our students do their master’s projects:
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  • Validation of analysis metod or Radium 226 in water
  • Study of Excitonic Energy Level Structure in Photosynthetic Antenna Complexes
  • Experimental realization of the generalized definition of pH value (so-called unified pH scale)
  • Measurement of the binding efficincy of synthetic molectlar receptors towards analytes of environmental and health concern
  • Developing an ATR-FT-IR-based procedure for quantitative analysis of materials usage in works of art
  • Building the EstCube Student Satellite
  • etc, etc …
  • Should you have interest in any of these (or other) topics you are welcome to contact Ivo Leito.

    Before the seminar, a questionnaire (anonymous) was distributed to the students addressing the AMS programme. The questions were about the usefulness of the programme in finding a job related to measurements or chemical analysis, about the general organization of the programme, quality of teaching, etc. The presentations were followed by a discussion of the responses. Many constructive comments and suggestions for improvements were received from the students.

    It is very pleasant, however, that the overall evaluation of the programme by the students was very high, both in terms of the quality of teaching and in terms of competitiveness of the graduates on the job market.

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    Liquid chromatographic separation of basic analytes is often hampered by problems, such as insufficient retention, wide and asymmetric peaks, etc, especially if carried out at acidic pH. Many modern HPLC coulmns can stand pH values up to 10 without problems and separation at a higher pH is often a good approach for liquid chromatographic separation of basic analytes, such as different amines. Unfortunately, the choice of buffer systems in the range of pH 7-10 suitable for LC/ESI/MS work is very limited. The main requirement for the electrospray ionization mass spectrometry is that besides suitable pH all the components of the buffer system should be volatile. This immediately excludes phosphate, carbonate, borate, etc buffers. On the other hand, the buffer should not compete with the analytes in the electrospray ionization process. This excludes most organic bases. The ammonia/ammonium acetate or ammonia/ammonium formiate buffers are the most used ones. Nevertheless, also use of these buffers and mobile phase pf pH aroun 9 often results in less than ideal separation and peak shape. Thus new LC/MS-compatible volatile buffer systems would be highly welcome.

    Karin Kipper from UT Institute of Chemistry has made a significant contribution in this field by introducing two new buffer compounds, two fluoroalcohols – 1,1,1,3,3,3-hexafluoro-2-propanol (HFIP) and 1,1,1,3,3,3-hexafluoro-2-methyl-2-propanol (HFTB) (Journal of Chromatography A, 2011, 1218, 8175–8180). She has found that these compounds offer interesting possibilities to adjust retention behavior of different analytes by using high pH values (ammonia is used for pH adjustment) and expand the currently rather limited range of ESI-compatible buffer systems for basic mobile phases. Good separation of different compounds was observed with excellent peak shape. The fluoroalcohols did not suppress the ionization of the analytes in the electrospray source and for several analytes ionization enhancement was observed. Thus, these compounds are suitable for electrospray mass spectrometry.

    All trends in retention of the acidic and basic analytes can be interpreted by the following model: the neutral fluoroalcohols are quite strongly retained by the stationary phase whereas their anions are less retained, thus their amount on the stationary phase is dependent on mobile phase pH; the anions of the fluoroalcohols form ion pairs in the mobile phase with the basic analytes; the fluoroalcohols on the stationary phase surface compete with acidic analytes thereby hindering their retention; the fluoroalcohols on the stationary phase bind basic analytes thereby favoring their retention.

    The suitability of these fluoroalcohols as buffer components for LC/ESI/MS analysis has been verified on the example of simple organic compounds (bases, such as amines, pyridines, anilines) as well as several antibiotics – three fluoroquinolones: ciprofloxacin, norfloxacin, ofloxacin; and two sulfonamides: sulfadimethoxine, sulfamethoxazole (Analyst, 2011, 136, 4587–4594).

    We hope that this novel approach will eventually gain popularity and we welcome any feedback on its practical use.

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    A new software package for measurement uncertainty calculation called MUkit (shortcut from: Measurement Uncertainty kit) has been recently made available by SYKE, the Finnish Environmental Administration. This is the first software package that offers direct support for laboratories in measurement uncertainty evaluation according to the increasingly popular Nordtest approach of measurement uncertainty estimation.

    The MUkit software is freeware and is available for download free of charge from the SYKE ENVICAL website. The capabilities of the software are described in the users manual available from the same website as well as in the recently published article Software support for the Nordtest method of measurement uncertainty evaluation. Teemu Näykki, Atte Virtanen, Ivo Leito Accred. Qual. Assur. 2012.

    Any feedback on the use of the software is most welcome!

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    Electrospray ion source (ESI) is the most used ion source type for connecting liquid chromatography (LC) with mass spectrometry (MS) due to its robustness and possibility to analyze a wide range of analytes. LC/MS in turn is currently the most used analytical technique for determining trace contaminants (pesticides, mycotoxins, drug residues, …) in the widest possible range of matrices (water, food, blood, …)

    ESI is a very good LC/MS ion source but it still has two major shortcomings. Firstly, ESI is in general not efficient in generating gas-phase ions (meaning, the large majority of the analyte molecules pass the ion source without being detected). Secondly, ESI is susceptible to the so-called matrix effect – decrease of the analyte response in the presence of compounds co-eluting with the analyte. These drawbacks lead to lowering the sensitivity and increase of the risk of possible false-negative results.

    Anneli Kruve from UT Chair of Analytical Chemistry has come up with an original idea how to improve the sensitivity of an ESI source and make it less susceptible to the matrix effects. The essence of the idea is to modify the nebulizer (the key component of an ESI source) by adding an additional capillary directing the nebulization gas right into the stream of solution (the thin innermost capillary on the image). The prototype of this ion source has been built (see the image) and experiments have shown that this design offers significantly enhanced ionization efficiency compared with the classic nebulizer design and leads to improved sensitivity (by three to 10 times) and decreases the detection limit, on an average 10 times. The patent application of this development has been filed and a communication has been published in J. Am. Soc. Mass Spectrom. (2012).

    Recent studies have shown that the matrix effect in the ESI source mostly arises from the competition of ionized analytes and matrix compounds for the droplet surface. It is expected that by more effective nebulization the net surface area of the droplets increases and thus the competition decreases leading to decrease or elimination of the matrix effect. Testing of this hypothesis is currently in progress.

    The gain in ESI sensitivity may open up new horizons in different fields of LC/ESI/MS application. It may become possible to detect different marker molecules at very low levels in complex biological matrixes in biochemical and medical analysis, possibly leading to e.g. early discovery of diseases; it may become possible to determine the background concentrations of organic pollutants in environment, which is very important for understanding and modeling their behavior in the environment; etc.

    (Image by Ave Saluvee)

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    On August 31, 2012 Irja Helm successfully defended her PhD Thesis High accuracy gravimetric Winkler method for determination of dissolved oxygen at Institute of Chemistry, University of Tartu. The essence of the work is development of a highly accurate gavimetric Winkler titration procedure for determination of dissolved oxygen content in calibration medium for optical and amperometric dissolved oxygen sensors.

    Dissolved oxygen (DO) content in natural waters is a very important parameter. Recent studies show decrease in DO content in several areas of world oceans. Processes leading to this decrease are not completely understood and it is very important to be able to measure DO content very accurately for studying the dynamics of these processes. Amperometric and more recently also optical oxygen sensors are widely used in DO measurements. These sensors need calibration and therefore solutions with accurate DO concentration are necessary. And this is where Irja’s method will be very useful.

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    On 31.08.2012 the introductory meeting for first-year AMS students was held. Sergei Jurtšenko gave overview of the AMS programme, timetable of autumn semester 2012 and some practical aspects of living and studying in Tartu. The PDF file of this presentation is available for download from here.

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    Klodian Dhoska, graduated from AMS in 2010 shared his thoughts about how the programme has influenced his life during the last two years:

    “Experience at Applied Measurement Programme has given to me a very good career. I am technical expert at Albanian Accreditation Directory, Head at Mechatronics Department on private University in Tirana, part-time lecturer at Polytechnic University of Tirana and in the end I am accepted as a full time doctoral student at Tallinn University of Technology. You don’t need to search for a good career because the career is following a succesful AMS programme at University of Tartu.”

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    The MSC Summer school finished on Jul 27, 2012. Kristjan Haav, one of the participants (from the AMS programme, University of Tartu) shared his impressions.

    Ivo: What would you single out as the top experiences in the summer school?

    Kristjan: From the professional viewpoint it was the experience of being the leader of our team “Magus Jook Laboratory” in the Student contest. I was elected leader by our group because it turned out that I had somewhat deeper knowledge about analytical chemistry than my groupmates. I had no similar leadership experience prior to the summer school and managing the work of an international group was quite a challenge. Eventually it worked out quite well – our team got 24 points out of 25 for the student contest. From entertainment point of view the top experience was certainly the surfing day on the ocean coast.

    Ivo: OK! So, I understand that the knowledge and skills that you have obtained from the first year of AMS were sufficient for participating in the Summer school?

    Kristjan: Yes. It was actually quite pleasant realize how many valuable things we have learned.

    Ivo: What is your overall impression of the summer school?

    Kristjan: It was much more challenging and exhaustive than I thought. It was two weeks of serious studying, both in theory and in practice. And it is not over yet – we still have homework to complete. I would say that especially the practical assignments at the Summer school were very interesting and useful.
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    As a nice counterbalance to the serious and challenging programme of the summer school last weekend there was a surfing outing at the summer school.

    All participants had the possibility to try surfing in the Atlantic Ocean under the guidance of professional instructors. It seems that they had a lot of fun!

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    On Monday, July 16, 2012 the fifth Measurement Science in Chemistry International Summer School started in Fatima (Portugal). In this edition, 48 students from thirteen countries participate. The dense and challenging programme will give the students opportunities to learn and practice almost every metrological aspect of analytical chemistry.

    Topics, such as Validation of chemical analysis procedures, Statistical basis of calibration, Traceability in chemical analysis, Measurement Uncertainty, including the Alternative Approaches for the Quantification of Measurement Uncertainty, ISO 17025, Sampling and sample preparation in food and environmental analysis, Customer-analyst interactions are included in the programme.

    Efforts are made to make the summer school more interactive (as opposed to listening to lectures). This is done via the student contest/game, accreditation visit to a real lab and numerous group work sessions.

    More information can be found at the MSC Website.

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    Alda Andersone from Latvia defended her master thesis on June 11, 2012. The title of the thesis was “The stereoselective synthesis of 2,2,5-trisubstituted tetrahydrofurans, oriented to the preparation of lilac aldehydes and alcohols”.

    The thesis was awarded the highest mark “A”. Alda talks about the thesis: “I prepared my master’s thesis in the organic chemistry field. The main goal of my work was to find out the best synthesis scheme to synthesize as pure as possible stereoisomers of 2,2,5-trisubstituted tetrahydrofurans. Main goal was achieved, 98% enantiomerically pure 2,2,5-THF enantiomer was synthesized”.

    Here are some of Alda’s comments about University of Tartu and the AMS programme:

    University of Tartu provided me with rich knowledge in theoretical and practical base. We had lots of practical trainings and interesting and useful information in lectures. And it was very useful that some information was overlapping between lectures – great possibility to repeat material.

    During study time I was working in the UT Institute of Technology in organic chemistry laboratory. And I would like to thank PhD Lauri Vares for accepting me in his research group. During master’s thesis work up time I was supervised by Ilme Liblikas, the best supervisor I ever had. Thank You, Ilme!

    Leaving University of Tartu with master’s degree in my pocket I feel much richer – I had a great opportunity to study in international programme, improve my English and make lots of new friends from different countries all over the world.

    I would like to thank prof. Ivo Leito for being such a great leader, and University of Tartu over all for hosting me.

    In the future I am definitely planning to use my knowledge in Chemistry and Applied Measurement Science. And probably at some point I will get PhD.

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    Hanno Evard defended his master thesis on June 11, 2012. The title of the thesis was “Study of paperspray ionization and its possible applications”.
    The thesis was awarded the highest mark “A”. Hanno talks about the thesis: “My master thesis topic was about studying a new ionization method for mass spectrometry – Paperspray Ionization. In the course of the study I got the possibility to work with different mass spectrometers including an FT ICR mass spectrometer. As it was the first time in University of Tartu to study this ionization method the work was very complicated. However with the help of my supervisor and other staff in the Chair of Analytical Chemistry the working was easy and fun. I found in the course of the thesis that the new method can be used to obtain information about composition of papers and to identify pesticides from citrus fruits bought from a supermarket. I will be working further with Paperspray Ionization in the course of my doctoral studies”.

    Here are some of Hanno’s comments about University of Tartu and the AMS programme:
    The past two years while studying in the Applied Measurement Science programme have been very interesting and fun. University of Tartu gives a wide field of education and strong practical experience on the studied subject. The teachers are friendly and ready to help with any problems that students might have. Moreover they are at the top of their fields and therefore the most qualified to teach the subjects. The laboratories and lecture halls are new and well equipped. Students have the possibility to use and study complex and expensive equipment. The programme gives you a good opportunity to meet people from all around the world.

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    AMS master's thesis defence 2012Seven AMS master’s candidates successfully defended their theses on June 11, 2012. Congratulations!

    The PDF files of all the theses are available for download from here.

    (See at the end of the list: Hanno Evard, Karlis Andersons, Alda Andersone, Eyüp Zorla, John Can Blackburn, Mykola Tverdokhlib, Juliia Demchuk).
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    On May 21-22, 2012 a workshop Validation, Traceability, Measurement Uncertainty: the Challenges for the 21th Century Analysts took place in Berlin. This workshop focused on the relationship between method validation, traceability and measurement uncertainty in various fields of quantitative analytical measurements. In addition to lectures there were two workshop sessions devoted to discussions about the practical problems of validation of analytical procedures, establishing and demonstrating traceability and estimating measurement uncertainty.

    Ivo Leito from University of Tartu participated in the workshop with the presentation Using method validation and performance data for estimating measurement uncertainty.

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    On March 23, 2012 an in situ interlaboratory comparison measurement of dissolved oxygen concentration EstDO-2012 was carried out at the Testing Centre of University of Tartu. Altogether 13 participants from Estonia (different institutions), Germany (IO Warnemünde), France (IFREMER) and Finland (SYKE) took part in the intercomparison. The participants used amperometric and optical (fluorescence quenching) sensors.

    There is a perception that measurement of dissolved oxygen concentration is simple. In reality it is not. Dissolved oxygen is an unstable analyte and its determination is affected by numerous uncertainty sources (a comprehensive overview of the uncertainty sources of amperometric dissolved oxygen sensors and ways of taking them into account is given in a recent review: Sensors 2010, 10, 4430-4455, open access). Therefore such comparisons between laboratories are essential for improving the quality of measurements made by laboratories.

    In situ intercomparisons are organized in such a way that all participants gather in the same place and make measurements on the same object. The “object” in this case was a basin of water with carefully controlled dissolved oxygen content. The basin was immersed in a themostat for temperature control and the water was stirred because the readings of the amperometric sensors depend on stirring. The sensors of the participants were arranged concentrically to allow similar intensity of water movement in the vicinity of the sensors. Picture on the right shows the basin and the sensors.

    Connected to the intercomparison was a demonstration of the primary semi-gravimetric micro Winkler titration method that has been developed at University of Tartu. This method offers very high accuracy and does not need calibration with water of known concentration of dissolved oxygen. More information can be found in a presentation Determination of dissolved oxygen – half-gravimetric Winkler given at the intercomparison.

    The final report of the EstDO-2012 intercomparison is available from the Intercomparisons website of the UT Testing Centre.

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    Organization of this intercomparison has been partly funded by the European Metrology Research Programme (EMRP), project ENV05 “Metrology for ocean salinity and acidity”. The EMRP is jointly funded by the EMRP participating countries within EURAMET
    and the European Union.

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    During Mar 13-16, 2012 Ivo Leito visited University of Shanghai for Science and Technology (USST) and gave a series of lectures/workshops for te students of USST.

    The lectures/workshops were the following:
    A Short Journey into Modern Analytical Chemistry
    Measurement Science and its importance for the Society
    Superacid derivatives in your pocket?

    The lectures triggered interesting discussions. The students wanted to know about the limits of modern analytical chemistry, about the possible uses of superacids, about the consequences of wrong measurement results. The joint residual message of the lectures was that accurate and reliable measurements (and chemical analyses) are one of the foundations hire Inflatable Bounce of modern science and technology and with their development the importance of accurate measurements is going to increase.

    This visit is expected to be the start of a fruitful collaboration between USST and UT. The visit was organized in the framework of and with funding from the Study in Estonia cooperation platform.
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    text by: Iuliia Demchuk
    Portugal… You will hardly find a person who doesn’t like it! This country is charming and most probably you will fall in love with it from the very first sight. Like it happened to me . Although I lived in Lisbon only, that city made a wonderful impression about the whole country 😉

    First of all, the nature! It’s just amazing! There are palm trees everywhere and the sun is shining all the days long. So, there are millions of options what to do at you free time : go for a walk, go off the beach and do surfing, or just simply stroll in the city center.

    When the weather is not so good ( which happens rarely), Lisbon can offer you many interesting museums, exhibitions and places of interest.
    There are also many bars, pubs, clubs, shops , malls, bla bla bla…
    However the most wonderful thing for me was local architecture – it is completely different from everything that you can find in Europe. Lisbon has its own style, which was influenced by African colonies and closeness to the ocean. So each time you hang out in the city center, you will always find something new and charming.

    But the most important thing and the main aim of my trip were studies and international experience. And I’m 100 % satisfied that I chose University of Lisbon for this purpose. Professors at the department of chemistry ( especially Ricardo Silva, Maria Filomena Camoes – thank you again for everything!!!!!) are highly qualified and professional teachers. On the other hand, they are the most welcoming, friendly and cooperative teachers that I’ve ever met. They are always glad to help you – with your studies, with courses selection or even with everyday affairs.

    During my Erasmus semester in Lisbon, I was studying a subject called “Quality in Analytical Chemistry” and doing a project “Assessment of the metrological performance of the identification and quantification of food dyes in aqueous solutions”. About the subject – it was very interesting, and it is practically very important for people dealing with measurements and analytical chemistry. It gives a deep and very detailed overview about development an validation of the analytical procedures, and I can personally say that I’ve learned a lot about the validation process . About the project – it was more practical, I had to do many measurements and deal with a lot of data, but it was interesting at the same time. All necessary equipment and chemicals were provided by the university, so I didn’t have any troubles with that. Also it was my first serious report in the field of analytical chemistry, so I didn’t have much experience and didn’t know how to organize it optimally, but thanks to Prof. Ricardo Silva and Prof. Maria Filomena Camoes, I managed to do it very well.

    All in all, but the semester in Lisbon fished very quickly, but it was one of the best times in my life and I will never forget it.
    Portugal, I’ll be back 😉

    Antonio Semakalu from Uganda defended his master thesis on February 28, 2012. The title of the thesis was “Gammmaspectrometrical Measurement of Radium Content in Water – Validation of Analysis Procedure”.

    The thesis is remarkable not only because it was awarded the highest mark “A”, but also because it was defended three months (!) in advance of the deadline. Antonio talks about the thesis: “It will be applied in research and in environmental and nuclear labs for studies and decisions making in environmental control”. One of Antonio’s supervisors Siiri Suursoo says: “Antonio did a huge work and significantly advanced our lab’s measurement capability in this area. We are very happy about this thesis.”

    Here are some of Antonio’s comments about Tartu, the AMS programme and his future plans:

    — Impression about the training at UT:

    “The major impressions I have are; Flexibility, Equipments and Environmental location. Training here allows flexibility in what you study. It gives you an opportunity to do any and as many courses you may want to do in any department without any obstacles (you just register it and do it). This has helped me to acquire many and different skill at one single study time. I managed to get knowledge from economics, chemistry and physics departments. The university has got all what you need to complete your course. All Equipments and every resource you may need are available. It location really has given me maximum concentration on my studies and students life has been fantastic. The people around the city and the students in the town really make one feel the university life”.

    —Future Plans:

    “Am now looking forward to do my research PhD in either nuclear studies or chemistry. Hopefully this can lead me to IAEA or professorship and research”.

    (text by John C Blackburn)

    Tartu is a different town in the summer. The days long and the streets quiet, Tartu is a student’s town, and is exciting when the students are in town. Its charm lies in its youthful atmosphere and historical buildings saved and renovated from before its Soviet days. Raekoja Plats is not only the town centre, but also the centre of all activity. The streets and the fun all radiate from Raekoja Plats and a long night may end, at Zavood.

    Settling into town at the beginning of the winter term it’s hard to imagine the brutality of Estonian winters, but those long days soon turn to long nights. Even when there is four hours of daylight it’s hard to call the weak light sunshine. But the ever still exciting student life gets anyone through the tough winters. Naturally those winters make great hours for studying as our course is highly demanding. Under snow Tartu is a medieval winter wonderland, like a fairy-tale! 

    When it seems like spring will never come, suddenly the days are long again and Tartu’s many parks turn green. The term winds down and that carefree student life turns to exams. Summer comes again, and alas the students go home and the town is quiet again.

    I knew nothing of Estonia prior to arriving; I felt like a real life Paddington Bear (Paddington Station being the start of my travels) with a note attached to a buttonhole in my jacket reading “Please look after this bear. Thank you,” and thank you Tartu, you did.

    Measurement science influences other sciences and sometimes from quite an unexpected angle. A recent review on extinction of the dinosaurs (the “Mass Extinction at the Cretaceous-Paleogene Boundary”, to put it in a scientifically correct way) published in the prestigious Science journal (Science 2010, 327, 1214-1218) confirmed that the most likely cause of dinosaur mass extinction was an asteroid impact at around 65.5 million years ago. Consequences of this event included a long dark and cold period of several years, as well as possible acidification of the ocean (as a consequence of a huge amount of sulfur compounds that were ejected into the atmosphere). This led to dying of most of the plants on the planet (which later largely recovered from seeds and roots) and most of the creatures that feeded on plants or on other creatures. Among them almost all dinosaurs.

    Interestingly, this hypothesis was originally proposed based on chemical measurement (analytical chemical) data! It was discovered more than thirty years ago (Science 1980, 208, 1095-1108) that in sediments of roughly that age there was sharply increased iridium content (by up to ca 100 times). This was interpreted as a consequence of an iron meteorite hitting the earth. Iron meteorites are quite rich in platinum metals and the fierce explosion that took place jumping castle for sale on the impact distributed the platinum metals into the atmosphere all over the world, where they thereafter precipitate and accumulate in the sediments.

    (Image: by NASA, via Wikipedia)

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    On Dec 10, 2011 the master’s seminars of the Applied measurement science of the autumn semester 2011 were concluded. Most of the presentations were based on the master’s thesis topics of our students. As is typical for our interdisciplinary programme, the topics were truely diverse, ranging from food quality to neutron detection, from drug residues in environment to building a student satellite. Here is a short (and not exhaustive) list of the areas in which our students do their master’s projects:
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  • Experimental realization of the generalized definition of pH value (so-called unified pH scale)
  • Developing novel ion sources for mass spectrometry (MS), allowing analysis of difficult samples with limited or no sample preparation and reducing the matrix effects in MS and LC-MS analysis
  • Measurement of the binding efficincy of synthetic molectlar receptors towards analytes of environmental and health concern
  • Developing a novel neutron detector for nuclear applications
  • Developing an ATR-FT-IR-based procedure for determination of inorganic pigments in paintings
  • Measurement of Radium in water by gamma spectrometry
  • Buliding the EstCube Student Satellite
  • etc, etc …
  • Should you have interest in any of these (or other) topics you are welcome to contact Ivo Leito.

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    On Nov 29, 2011 a seminar was held in Tallinn, which summarized the results of the study “Metrology in Estonia, its current status, economic impact, trends and needs analysis” carried out during 2010-2011 jointly by BDA Consulting, University of Tartu and Metrosert Ltd. The key of the used methodology was a sophisticated questionnaire, which was distributed to a large number of industrial and related companies resulting in 450 responses. The report of the study provides a thorough analysis of the responses to these questionnaires, both in terms of measurement areas and in terms of industry sectors.

    On the seminar presentations were given by Marikai Karilaid (project coordinator, BDA) on methodology of the study, Toomas Kübarsepp (Metrosert) on the status and needs analysis of the national metrology infrastructure, Kaarel Simson (Metrosert) on the economic impact of metrology on economy in general and industry in particular. The seminar was completed and summarized by Ivo Leito (University of Tartu) with the presentation Measurements and chemical analyses in Estonia: Trends for the coming years outlining the trends in the measurement area expected for the coming years. The english translation of this latter presentation is available from here (with a couple of additional remarks). Around 30 repersentatives of industry and stakeholders of measurement infrastructure attended the seminar. The final report (in estonian) will be available within couple of months.

    An important result of the study, having relevance to the AMS programme, is that the importance of education in the area of measurements and chemical analysis is increasing and the employment oulook for people having high-level education in measurement science or analytical chemistry is very good.

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    This week a joint project will finish between University of Tartu and the German National Metrology Institute (PTB – Physikalisch-Technische Bundesanstalt) on providing training in Metrology in Chemistry for Indian analytical chemists. In the framework of this collabortion Ivo Leito carried out three one-week training sessions in different parts of India (Lucknow, Mysore and Nagpur). Altogether more tha 60 analytical chemists from different sectors (food, environment, industrial analysis, etc) were trained. Picture on the left is from the last training session carried out in October 2011 at National Environmental Engineering Research Institute (Nagpur).

    The training sessions were based on the course Metrology in Chemistry, which is one of the core courses of the Applied Measurement Science (AMS) programme, and covers all the main concepts and topics of Metrology in Chemistry. The training sessions contained both lectures and also practical examples on usage of the acquired knowledge. Selected course materials are available at the above address under the link “See study materials”. If you are more deeply interested in the content of the course or the AMS programme, you are welcome to contact Ivo Leito.

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    For elimination of the disadvantages of the traditional procedure of smoking of fish and meat the so-called liquid smoke has been developed. Some steps during the production of liquid smoke reduce the PAH concentration in liquid smoke and in the resulting fish products. The solutions of a liquid smoke concentrate are treated for the removal of toxic compounds by a multilevel filtration which allows elimination of the toxic components while keeping the flavor. The safety of the resulting fish or meat depends on the concentration of this additive. Some manufacturers can exceed the recommended concentration of a liquid smoke in order to hide from smell of stale fish.
    When smoked using the natural smoking conditions the fish or meat will contain the natural preservatives. The liquid smoke adds flavour and appearance to the food, but does not help to preserve it. Therefore, in order to avoid deterioration of the products, sometimes preservatives are added. This way the liquid smoke can become quite unhealthy. This is actually a substitution of certain natural unhealthy compounds by artificial unhealthy compounds. The European Food Safety Authority (EFSA) found in 2010 that a smoke flavouring product which is obtained from beech wood, as AM01, may be toxic to humans.
    Now, what to prefer – old traditions or new technologies? Tinted production or a poisoning of an organism with carcinogens? The choice remains behind the consumer (Image: Wikipedia).


    Today on 27.09.2011 on the Laboratory days event at Finnish Environmental Administration – SYKE (Helsinki, Finland) Ivo Leito gave a presentation “Education in Metrology in Chemistry – why and how?”. The first part of the presentation demonstrates the strong need for analytical chemistry experts in the society and the second part describes the activities in progress at University of Tartu and its partners in teaching of analytical chemistry and metrology in chemistry focusing on the Applied Measurement Science international master’s programme of University of Tartu and the international consortium Measurement Science in Chemistry.

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    The winner of the title “teacher of the year” in the Realia et Naturalia field in 2011 is Associate professor of analytical chemistry Koit Herodes. He teaches the “Practical Chemical Analysis” course of AMS. This title is each year given to four best teachers (one in every field: Realia et Naturalia, Humaniora, Medicina, Socialia) of University of Tartu based on the feedback from students. We are glad that our programme has Koit on board!

    Read the official announcement

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    On 26.08.2011 the introductory meeting for first-year AMS students was held. Ivo Leito gave overview of the AMS programme, timetable of autumn semester 2011 and some practical aspects of living and studying in Tartu. The PDF file of this presentation is available for download from here.

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    Last week (on July 22, 2011) the closing ceremony of the MSC Summer School 2011 took place in Poznań (Poland). Results of the learning evaluation and student game were presented and certificates were awarded to the participants. The next MSC Summer School will take place in July 2012 in Portugal.

    Student Iuliia Demchuk (University of Tartu) talks about her impressions of the summer school: “Generally, I’m very satisfied with the participation in this summer school and I have very positive impression about it”.
    Here are some of her specific comments:

    1. Visit to the Ecology Station in Jeziory

    • This was an interesting practical tutorial about sample preparation and a good possibility to spend the whole day in the open air.

     

    2. Visit to accredited lab

    • It was very interesting to see the ISO 17025 standard “in work” and have the possibility to ask questions about the work of ISO. It is always useful to see the labs for chemical, physical and microbiologocal analysis. And the “smelling room” – that was something new for me!

    3. The “role playing game” (contest of student teams)

    • A good chance to work with people from different countries and a possibility to learn something new from the members of your team. It is very educative to experience interaction with the customer like in “real life”

    4. Comments about the material presented during the lectures:

    • As I’m a physicist, my knowledge in the field of chemistry is not deep. So it was at times quite difficult for me to understand some of the examples presented. Maybe the differences in the background of different people should be taken more into account in the future and the examples will be made better understandable for everyone.

    On Monday, July 11, 2011 the fourth Measurement Science in Chemistry International Summer School started in a west-central city of Poland in Poznań. There are students from fourteen countries. The summer school covers a wide-ranging list of topics: Importance of reliable measurements to implement EU legislation, Basic aspects of uncertainty, Validation of chemical analysis, Traceability in chemical analysis procedures, ISO 17025, On the use of Certified Reference Materials, Ecology Station in Jeziory: sampling, Alternative Approaches for the Quantification of Measurement Uncertainty, Visit to accredited lab (Wodociągi Poznań), Basic statistics, practical examples. Special emphasis is put on group works and learning by role play.

    On Jul 05, 2011 Anneli Kruve defended her PhD thesis Matrix effects in liquid-chromatography electrospray mass-spectrometry (LC-ESI-MS) at the Institute of Chemistry, University of Tartu.

    Electrospray ionization (ESI, ESI ion source) is currently the most popular ionization mode in LC-MS (Liquid chromatography mass spectrometry, LCMS). LC-ESI-MS has become the premier technique for a large number of different analytical tasks, ranging form pesticides determination in fruit and vegetables to drug residues in sewage sludge. However, a major drawback of LS-ESI-MS is the so-called matrix effect – ionization suppression or enhancement of the analyte of interest by other compounds present in the sample and co-eluting with the analyte (see here for the definition of matrix effect). The matrix effect, if present, can cause large uncertainties in quantification using the LC-ESI-MS technique.

    The thesis presents four original approaches for combating the LC-MS matrix effect developed by Anneli:
    1. Extrapolative dilution;
    2. Multilinear (PLS) calibration using background ions;
    3. Taking matrix effect into account in measurement uncertainty of the analysis result;
    4. Reducing matrix effects by optimization of ESI-MS parameters.

    The first two approaches are essentially approaches for correcting for matrix effect. The third approach permits accounting for matrix effect via measurement uncertainty. The last one is about reducing matrix effect. These approaches, together with an investigation of the effect of sample preparation on ESI MS matrix effect and a comprehensive overview of LC-ESI-MS matrix effect in the introduction part make this thesis a genuine “LC-ESI-MS Matrix Effect Toolbox” for practitioners.

    If you wish to read the above cited articles but do not have online access, please contact us.

    (Sometimes the term matrix effect is used synonymously to “matrix suppression”. This is incorrect: matrix effect can sometimes also mean matrix enhancement. Sometimes the ESI-MS matrix effect is termed simply as MS matrix effect. These terms are not synonymous, as different effects are inherent in different ion sources.)
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    In couple of weeks – on Sunday Jul 10 – the 2011 Summer School of the Measurement Science in Chemistry consortium will start. This is already the fourth of its kind and is this time organized by University of Warsaw and Adam Mickiewicz University (Poland). The summer school will take place in a west-central city of Poland in Poznań. Approximately 40 participants from Slovenia, Serbia, Bulgaria, Portugal, France, Estonia, Finland, and Poland are expected.

    Two AMS students defended their master’s theses on June 8, 2011 at 10.15 a.m. (Tartu, Ravila Street, 14A, room 1021). The topics of the theses are related to testing of electrical power sources (Martynas Pelakauskas – ESTCube-1 Satellite Electrical Power System Battery Subsystem Design and Testing) and measurement of air exchange in buildings (Cagatay Ipbüker – Air Change Rate of Buildings. A Case Study). The PDF files of all the theses are available for download from here.

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    Modern technologies allow very accurate measurements of atomic weights and isotope ratios of elements. This is of high importance in solving research problems in others fields. For example, accurate measurement of isotope ratios of carbon in the sample can be used for assessment of of quality of food. In doping investigations distinction between the isotope patterns can also be useful – the distribution of isotopes in the pharmaceutical testosterone and in the testosterone produced by the human body is different. At the present time in the periodic table there are some values of atomic weights that were determined more than a century ago. Nevertheless, recently the data obtained by mass spectrometry has been useful in decreasing the measurement uncertainty of atomic weights.

    For example, in the case of carbon, the highest abundance of the 13C isotope is observed in the matter found in the deep sea. Carbon obtained from such matter has an atomic weight value of 12.011505. The uncertainty in this atomic weight value due to the uncertainty in the delta-value determination is 0.000003.

    This is an example of the situation encountered with many elements that the atomic weight depends on a place of extraction of the element from the Earth`s crust. The International Union of Pure and Applied Chemistry (IUPAC) have recently published the new table of Standard Atomic Weights with updated atomic weight values for ten elements: hydrogen, lithium, boron, carbon, nitrogen, oxygen, silicon, sulfur, chlorine and thallium. The new values more precisely reflect the isotopic distribution of these elements in the Nature.

    The atomic weights are expressed as intervals, having upper and lower limits. For example, for nitrogen the value of atomic weight is now 14.0067 and according to new approach by IUPAC is presented in the form of an interval: from 14.00643 to 14.00728. This reflects the dependence of the relative atomic weight on the source of the element. IUPAC hope to publish a new periodic table in the near future (Image: Wikipedia).

    Unfortunately, it is not rare that during preparation of food substances with cancerogenic and/or mutagen activity are unwillingly introduced into food. A typical representatives of this group of dangerous substances are N-nitrosamines (NAs) which are found in various meat products. Earlier we already spoke in this blog about the presence of these compounds in beer.

    The formation of NAs in meat proceeds via so-called nitrosation reaction, which is a complex process and a large number of substances can influence the reaction. The “starting materials” for NA formation in meat products are nitrate, nitrite, primary, secondary, and tertiary amines, amides, proteins, peptides, and amino acids or precursors of these, which are transformed into NA precursors by microbial action. NAs are formed after cooking, by an oxygen-dependent mechanism, the key step being the oxidation of nitric oxide and the formation of higher nitrogen oxides, which could act as direct nitrosating agents. The nitrosating agent responsible for the formation of NAs in fried meat might be N2O3, formed during heating of nitrite in meat, or NO radical formed by dissociation of N2O3 at high temperature.
    Of key importance in obtaining information on the content of NAs in food and possibilities for its reduction are reliable analysis methods for determination of NA concentrations. One such analytical method – based on the gas chromatography mass spectrometry – has been developed five years ago at the Tartu laboratory of the Estonian Health Board in collaboration with University of Tartu and published in journal Food Chemistry. It has been cited 9 times since its publication. The limit of detection and the limit of quantitation for this method were approximately 0.09 and 0.29 mkg/kg, respectively. The recovery of NAs in meat products varied from 79% to 88%, which can be considered very good for this kind of demanding analysis. Total concentrations of NAs in 386 studied samples of meat ranged from non-detectable to 30 mkg/kg. The highest levels of NAs were found in samples of fried meat. Relatively high level was found in grilled meat, in smoked pork, in half-smoked sausage, and in ham. With the addition of sodium nitrite, one can observe roughly linear increase in concentration of NAs in fried and raw meat. About 73% of NAs are concentrated in fat of baked mutton. In fried pork, the concentration of NAs in fat exceeds the concentration in lean 6 times. Apparently, the temperature and time of cooking, the method of cooking, residual and added nitrite concentration, the concentration of NA precursor and storage conditions of meat have a significant effect on the concentration of NAs (Image: Wikipedia).

    The light-emitting diode (LED) is a semiconductor device, which converts electric current into visible radiation, i.e. visible light. LEDs were discovered by accident in 1907, but no practical use was made of the discovery for several decades. Now they can be encountered virtually everywhere. LEDs are used in applications from standard indicators on stereo equipment and laptops to traffic lights and automotive lighting (Image: Wikipedia). The production and usage of LEDs has enjoyed an explosive growth over the last several years with no end in sight. In comparison with compact fluorescent and incandescent bulbs, LEDs are non-toxic, have higher damage resistance, lower energy consumption, longer lifetime and smaller size.  It is speculated that by the year 2025, LEDs will become the most widespread light source in apartment houses and offices.

    As LEDs have become more sophisticated, the need for accurate measurement of their optical properties has increased. Until recently, LEDs were primarily used as indicator lights and their main characteristic was luminous intensity (expressed in millicandela). However, due to the increasing demand for LEDs as a replacement to incandescent in the general illumination market, the Lumen is now often used as a unit of measurement for light output. The measurement of the total luminous flux of light sources is generally done by one of two methods: goniophotometer or integrating sphere. The measurement by a goniophotometer may be more accurate but more time-consuming in operation than the integrating sphere method. As a result, the integrating sphere method is preferred in many industrial measurements due to its ease of operation and quick response.

    It is clear that the measurement of light intensity is usually significantly less accurate compared to electrical characteristics such as voltage, current or resistance. There are many factors such as color, device geometry, alignment of the LED into a test fixture, temperature etc. that cause uncertainty in the measurement results. Systematic errors are introduced when using traditional methods (developed for the incandescent bulbs) for measuring the total luminous flux of LEDs since an LED is quite different from traditional light sources in terms of physical size, flux level, radiation spectrum and spatial distribution.

    Research is currently ongoing to develop and standardize reliable measurement methods of the optical properties of LEDs.

    LC-ESI-MS instrument at University of TartuLC-MS (Liquid chromatography mass spectrometry) with ESI (electrospray) ion source (LC-ESI-MS) enjoys ever increasing popularity as a powerful and versatile analytical tool. It has become the number one technique for a large number of different analytical tasks, ranging form pesticide determination in fruit and vegetables to drug residues in sewage sludge. A major drawback of this technique is the so-called matrix effect – ionization suppression or enhancement of the analyte of interest by other compounds present in the sample and co-eluting with the analyte. The matrix effect, if present, can cause large uncertainties in quantification using the LC-ESI-MS technique.

    In principle, every effort should be made to reduce (or preferably eliminate) the matrix effect or to take it into account. However this can be extremely work-intensive – not least because of the high variability of matrix effects – and thus impractical at a routine laboratory. However, if the matrix effect exists and cannot be eliminated then it should be taken into account as an uncertainty source in the measurement uncertainty estimate of the result. Although this situation has been well recognized quite some time ago, interestingly, for a long time there was no understanding among the LC-MS practitioners as of how to estimate the uncertainty due to the matrix effect.

    Recently Anneli Kruve from University of Tartu developed an approach for evaluating the uncertainty in LC-ESI-MS due to matrix effect. Her approach is based on evaluating the matrix effects for the same analyte in different matrixes and presenting the data in the form of a matrix effect graph. From this graph it is then possible to calculate the uncertainty contribution of matrix effect to the analyte content in the sample. This work has been published in the Journal of AOAC International 2010, 93, 306-314.

    (If you wish to read this article but do not have online access, please contact us)

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    Smoking as a way of preparation of fish and meat has been known to the humankind since the Stone Age. Smoking represents set of the chemical, thermal, diffusive and biochemical processes proceeding in preliminary salted product. Smoked fish contains compounds that are favorable and also compounds that are hazardous for human health. The advantage of eating smoked fish is that it has a high protein content and at the same time is low in saturated fat. On the other hand, eating too much of smoked fish can increase the risk of stomach cancer.

    Traditional way of fish smoking is a preservation method giving a characteristic flavour and colour to the product. However during this process undesirable compounds can be formed, mainly the polycyclic aromatic hydrocarbons (PAHs). These molecules are produced during pyrolysis of organic material that is used for generation of the smoke, mainly wood. It has been established that the content of carcinogenic PAHs in smoked fish most depends on smoking temperature and smoking time. The levels of PAHs in raw and cold-smoked fish are lower than the levels in hot-smoked fish samples. Of key importance to obtain such data is a reliable analysis method for determination of PAH concentrations. Such analytical method – based on the gas chromatography mass spectrometry – has been developed few years ago at the Tartu laboratory of the Estonian Health Board in collaboration with University of Tartu and published in the Journal of Food Composition and Analysis.  It has been cited 17 times since its publication, indicating strong interest in the subject.

    On 28.03.2011 Ivo Leito gave talk “ATR-FT-IR spectroscopy in the region of 550-230 cm-1 for identification of inorganic pigments” at the the 241th ACS National Meeting, Spring 2011 in Anaheim (CA).

    The presentation describes an analytical method for recording ATR-FT-IR spectra of inorganic pigments in the low wavenumber range (550-230 cm-1), which markedly extends the applicability of ATR-FT-IR spectroscpoy in identification of inorganic pigments that are important for the conservation of cultural heritage in different art objects.

    The reference spectra presented in the talk (and many more) are available from the address http://tera.chem.ut.ee/IR_spectra/

    Due to the nature of the ATR phenomenon poor-quality spectra are generally obtained from pure pigments, especially in the low wavenumber range. For obtaining good-quality spectra the pigments are mixed with linseed oil (in roughlt 1:1 ratio) and ATR-IR spectra are recorded from such mixtures. It is demonstrated on the example of 47 inorganic pigments widely used in historical paintings that this spectral range, essentially devoid of absorption peaks of the common binder materials, can be well used for identification of inorganic pigments in paint samples.

    This developed approach markedly extends the possibilities of pigment identification/confirmation by ATR-IR spectroscopy. In some cases the method can be used alone for pigment identification and in many cases it provides useful additional evidence for pigment identification using other instrumental techniques. Several case studies of pigment identification of real paint samples using the developed method are presented.

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    On a seminar on measurement quality in the framework of the conference ChemBio Finland 2011 a presentation “Metrology in Chemistry – from pipette to mass spectrometry, from National Metrology Institute to student lab” was given by Ivo Leito. The presentation gives an overview of why measurement science is important (on the example of chemical measurements) and what is done at University of Tartu and in the MSC Euromaster consortium for education in this field.

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    In the process of development and perfection of measurement technologies it became clear that all standards are not ideal. At measurement standards of the basic units it is necessary to take not man-made objects but much more perfect samples already created by the nature. The National Institute of Standards and technologies of the USA together with the metrological organizations of other countries are taking the first steps toward revision of the international system of SI, which forms the basis of all modern measurements. In the new system all seven base units will be based on constants of the nature (currently only Kelvin, second and meter are based fully on constants of the nature). This will bring measurements to new levels of accuracy. In the possible revision of the SI system, the most significant change would be in the kilogramm. It is currently the only SI unit that is still defined by an artifact.

    Within the existing SI, the mass unit is defined in terms of the International Prototype Kilogram (a 122 year old platinum-iridium cylinder). This definition of the kilogram creates certain problems, because the mass of this prototype changes slightly in time. A possible solution to this problem was proposed by two American scientists from the Institute of technology of Georgia in 2007. They suggested to consider as the standard of the weight a carbon cube from with strictly quantity of atoms. As the weight of each atom is constant,  the weight of this cube is also constant. Researchers have calculated that the cube with the weight 1 kilogram will consists 50184513538686668007780750 atoms, and the length of its side will be 8,11 centimeters. The first ideas of this research were published in 2007 in American Scientist. For three more years the scientists worked on details and have now presented a new article.

    The American physicists have attended to a problem of the standard of kg and have chosen as “a reference” element carbon with an ulterior motive – before they were engaged in specification of number of Avogadro – one of the fundamental constants, defining, how many particles are contained in one mole of any substance. Though this number also is one of the most important things in chemistry, its exact value is not known. Its value is known with an uncertainty: Na = (6.022145 ± 0.000016) × 1023 mol−1 (k = 2). The number of Avogadro was picked so that weight specified in grams equaled to weight of a molecule (atom) in nuclear mass units. The atom of carbon 12C has weight of 12 nuclear mass units so, one mole of 12C has a mass of 12 grams.

    Having now respecified the number of Avogadro and having accepted its value equal 844468863 (602214098282748740154456), researchers could calculate the necessary number of atoms of carbon in the standard.

    However the scientists from Georgia have competitors. For example, at the US National Institute of Standards and Technology work is in progress for development of the concept of electronic kilogram using the so-called Watt balance. This way kilogram would be defined by current and voltage which are necessary for creation of the magnetic field, capable to counterbalance a weight of one kg. This way is in principle very good, as it allows achieving high precision (it is based on use of one more fundamental constant – the Planck constant). However the experiment is extremely complex.

    One more variant for definition of the new kilogram standard is via a silicon sphere, which parameters are calculated in such a manner that it will contain a strictly known number of atoms. Such sphere has actually been created, but there were immediately the complexities similar to the complexities of the present standard – the sphere loses a part of the Si atoms with time and, besides, a film of silicon dioxide is formed on its surface.

    At the moment it is not clear, whether there will be the carbon standard, silicon standard, electronic kilogram or scientists will think up a fourth, more convenient, way. But it seems rather probable that the cylinder stored in France within 120 years will soon retire. (Image: Wikipedia)

    Beer is the world’s most widely consumed and probably the oldest of alcoholic beverages; it is the third most popular drink overall, after water and tea.
    What is beer? Simply put, beer is a fermented, hop flavored, malt sugared, liquid. The basic ingredients of beer are water, malt, hops, and yeast. The main active ingredient of beer is alcohol, and therefore, the health effects of alcohol apply to beer.
    Besides, beer may contain carcinogenic nitrosamines, which explains its relationship with certain types of cancer. Nitrosamines generated during malt production will pass into beer. Their concentration in malt depends on the type of the drying technique. The main compound that is monitored in malt and beer is nitrosodimethylamine (NDMA). A study in University of Tartu has demonstrated that NDMA concentration depends on alcohol content of beer. The highest NDMA concentration was observed in alcohol-free beer. Stronger beers tend to contain lower level of NDMA than beers with lower alcohol content. In the dark beer the level of NDMA is higher than in light beer with the same percent of alcohol. The analytical method on which the determination is based has been published as an article in journal Food Chemistry. At the same time beer contains a powerful molecule that helps protect against breast and prostate cancers. Found in hops, the substance called xanthohumol and is classified as a flavonoid, an antioxidant that has anti-cancer properties. The researchers found that xanthohumol is six times more powerful an anti-oxidant than those found in citrus fruits, and four times stronger than those in soy foods. Hops give beer its bitter flavour, so traditional bitters and ales will contain far more of this substance than light lagers. Unfortunately, drinking beer cannot be considered a method of cancer prevention. Most beers have low levels of xanthohumol, and its absorption in the body is also limited (Image: Wikipedia).

    Most people (especially in the northern countries) have had the extremely annoying experience that in some (usually somewhat colder than average) morning the car will not start, because there is not enough charge in the battery.

    The battery is a critical system component of a car. This is especially true in winter, because the colder the weather a) the more viscous are all the lubricants and thus the more difficult it is to make the engine revolving and b) the higher is the internal resistance of the battery and thus the lower is the maximum current that can be produced during starting.

    Usually battery problems do not emerge suddenly but develop gradually. Therefore, by some simple measurements and monitoring of the battery state the probability of battery failure at some critical moment can be significantly reduced. What is needed is a voltmeter capable of showing reliably voltages in the range of 10 to 16 volts with 0.1 V readability and accuracy preferably not much worse than ±0.1 V. Such devices are usually available as multimeters and are able to measure also current and resistance (and many more things in the case of sophisticated models).

    Dependence of the open-circuit voltage of a 12 V lead acid battery on its charge state

    A most important property of the lead acid battery (which makes it very different from the lithium ion battery used to power many electronic devices) is that it should be kept fully charged all the time and never be fully decharged. Keeping battery decharged for some time will irreversibly reduce its capacity and the maximum current that it can deliver during starting the car. This happens because of a process known as sulfation. Very important for keeping the battery charged is the ability of the car’s generator to supply sufficient charging voltage when the engine runs, so that after the partial discharge of the battery during starting the engine the battery would be brought to the fully charged state as soon as possible.

    Thus, to be in control of the situation, two measurements should be made from time to time:

    1. Measuring the open-circuit voltage of the battery. This should be done without engine running and without any electric devices switched on. This voltage for a fully charged battery is 12.6 .. 12.8 V. If this voltage drops below 12.4 V sulfation will slowly start. The image on the right shows the dependence of the open-circuit voltage of a 12 V lead acid battery on its charge state (source: Wikipedia). If after a ride of, say, 2 hours the open-circuit voltage is not within the range indicated above then there is a strong reason to suspect that the electric generator of the car is not in order.

    2. Measuring the charging voltage when the engine is running. This voltage should be in the range of 14.0 .. 14.4 V. This measurement should be done with headlights on and engine running at ca 2000 rpm. Value below 14.0 V indicates insufficient charging. Value above 14.4 V indicates overcharging. At such high voltages the water in the electrolyte is slowly electrolyzed and the electrolyte volume decreases. Charging voltage significantly higher thatn 14.4 V can damage the electric system of the car.

    If significant deviations of the above voltages from the specified regions are discovered then a specialist should be consulted.

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    Superacidity of the Strongest SuperacidsAmong the central reserach topics at Institute of Chemistry, University of Tartu is design and acidity measurements of superstrong acids – so-called superacids. Superacid is an acid that is more acidic than sulfuric acid (H2SO4), which is usually considered an epitome of a strong acid. Superacids and their derivatives already now have numerous applications in chemical technology and materials science. Just a couple of examples: a large share of the gasoline sold routinely at gasoline stations has been produced by processing with superacidic catalysts; salts of superacids are used in all Lithium ion batteries. Therefore it is fair to say that almost everyone of us daily uses items or materials that are in some way related to superacids. For their successful usage measurements of their strength are very important. Measuring the acid strength of a superacid is not easy.

    Superacids in 1,2-DichloroethaneThe current status of this research at University of Tartu was summarized by an invited presentation on 20.01.2011 at Ludwig Maximilian University of Munich in a seminar specifically devoted to this topic. The image on the top left shows some of the strongest superacids ever envisaged by the humankind together with their predicted acidities in the gas phase. The image on the right displays the most acidic superacidity scale ever measured in a constant composition medium (See the original publication J. Org. Chem. 2011, 76, 391-395 for more details). This scale – built in 1,2-dichloroethane – lists the well-known mineral acids (sulfuric acid, hydrochloric acid, trifluoromethanesulfonic acid, perchloric acid, etc) as well as specifically designed superstrong acids (e.g. representatives of the cyanocarbon superacid family and trisulfonylmethane superacid family) and allows comparing their acidities (the stronger is the superacid, the lower it is positioned on the acidity scale).

    For more information, please see the full presentation given at the seminar and the acid-base chemistry page at University of Tartu.

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    More than half of the solar energy that reaches the Earth and is absorbed by land srfaces is used for evaporation of water. Evapotranspiration is a joint process of moisture evaporation from the land and transpiration from plants. Recently a survey (Nature 2010, 467, 951) was completed taht analyzed and generalized data from 253 globally distributed water vapor flux measurement and monitoring stations over a time span of 1982 to 2008. The results indicate that during 1982 to 1997 there has been an increase of the global annual evapotranspiration by 7.1 ± 1.0 mm. After that period increase of the global evapotranspiration seems to have ceased. The prime reason for this is the decrease of the average global soil moisture level.

    A question of utmost importance is whether these changes reflect the natural climate variability or indicate a trend in the global water cycle, possibly being a consequence of a global climate change.

    The key to answering this question is the quality of the measurement data provided by the monitoring stations. Two aspects are critical: (1) The temporal stability of the measurement systems, so that measurement data obtained over a long time period would be comparable and (2) comparability of data between stations operating in different locations around the globe.

    (Image: Wikipedia)
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    OECD has published the results of PISA 2009, the most recent edition of its Programme for International Student Assessment. The assessment methodology evaluates a number of abilities and skills of students, such as accessing and retrieving, integrating and interpreting information, their knowledge of mathematics and science, etc.

    The rankings list is topped by China, Finland and Korea. Estonia is sharing the 13-14th position together with Switzerland (not a bad company!), closely followed by Poland, Iceland and United States. Interestingly, by student performance Estonia beats such internationally known education strongholds as Sweden, Germany, Denmark and the UK.

    In Science Estonia occupies the 9th place, between New Zealand and Australia.

    See the official PISA 2009 site for full information.

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