19 results
Search Results
2. Optical biochemical and chemical sensors – Europt(r)ode VIII.
- Author
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Gauglitz, Günter
- Subjects
EDITORIALS ,CHEMICAL detectors ,NUCLEAR receptors (Biochemistry) ,SIGNAL detection ,CONFERENCE proceedings (Publications) - Abstract
The editorial reflects on the proceedings of European conference on optical, biochemical and chemical sensors entitled "Europt(r)ode VIII" held in Tubingen, from 2-5 April, 2006. Papers covering various topics were presented at the conference, including nuclear receptor signalling, piezo effects in automobile fuel injectors, and others. The article states that a few papers were presented in the current issue and the remaining papers would be published in the subsequent issues of the journal.
- Published
- 2006
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3. Time series analysis of long-term data sets of atmospheric mercury concentrations.
- Author
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Temme, Christian, Ebinghaus, Ralf, Einax, Jürgen W., Steffen, Alexandra, and Schroeder, William H.
- Subjects
TIME series analysis ,ATMOSPHERIC mercury ,ATMOSPHERIC chemistry - Abstract
Different aspects and techniques of time series analysis were used to investigate long-term data sets of atmospheric mercury in the Northern Hemisphere. Two perennial time series from different latitudes with different seasonal behaviour were chosen: first, Mace Head on the west coast of Ireland (53°20'N, 9°54'W), representing Northern Hemispherical background conditions in Europe with no indications for so-called atmospheric mercury depletion events (AMDEs); and second, Alert, Canada (82°28'N, 62°30'W), showing strong AMDEs during Arctic springtime. Possible trends were extracted and forecasts were performed by using seasonal decomposition procedures, autoregressive integrated moving average (ARIMA) methods and exponential smoothing (ES) techniques. The application of time series analysis to environmental data is shown in respect of atmospheric long-term data sets, and selected advantages are discussed. Both time series have not shown any statistically significant temporal trend in the gaseous elemental mercury (GEM) concentrations since 1995, representing low Northern Hemispherical background concentrations of 1.72±0.09 ng m
-3 (Mace Head) and 1.55±0.18 ng m-3 (Alert), respectively. The annual forecasts for the GEM concentrations in 2001 at Alert by two different techniques were in good agreement with the measured concentrations for this year. [ABSTRACT FROM AUTHOR]- Published
- 2004
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4. New miniaturized clean-up procedure for hair samples by means of microextraction by packed sorbent: determination of cocaine and metabolites.
- Author
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Rosado, Tiago, Gallardo, Eugenia, Vieira, Duarte N., and Barroso, Mário
- Subjects
HAIR analysis ,METABOLITES ,TANDEM mass spectrometry ,COCAINE ,HAIR ,METHYL formate ,COMPLEX matrices - Abstract
Cocaine is still one of the most commonly used illicit substances worldwide, with an estimated 4 million users in Europe in the last year. Hair samples have been widely used for the determination of episodic or repeated consumption of this substance, but the use of miniaturized techniques for hair sample clean-up has been challenging due to the sample complexity. Despite hair's complex matrix, MEPS provides a method that is fast, reduces the volume of extraction solvents used, and offers low-cost options (since extraction beds may be reused several times). Microextraction by packed sorbent using a mixed-mode sorbent was optimized for hair sample clean-up in order to determine cocaine, benzoylecgonine, ecgonine methyl ester, norcocaine, cocaethylene and anhydroecgonine methyl ester by gas chromatography coupled to tandem mass spectrometry. The method was fully validated according to internationally accepted criteria, presenting good linearity between the limits of quantification (0.01–0.15) and 5 ng/mg. Precision and accuracy resulted in coefficients of variation typically lower than 15%, with mean relative errors within ±15% for all compounds, except for the limit of quantification (±20%). The present work describes the first application of microextraction by packed sorbent for the concentration of cocaine and metabolites extracted from hair samples. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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5. Inter-laboratory study of an optimised peptide mapping workflow using automated trypsin digestion for monitoring monoclonal antibody product quality attributes.
- Author
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Millán-Martín, Silvia, Jakes, Craig, Carillo, Sara, Buchanan, Tom, Guender, Marc, Kristensen, Dan Bach, Sloth, Trine Meiborg, Ørgaard, Martin, Cook, Ken, and Bones, Jonathan
- Subjects
MONOCLONAL antibodies ,PRODUCT attributes ,PRODUCT quality ,DIGESTION ,POST-translational modification ,TRYPSIN - Abstract
Peptide mapping analysis is a regulatory expectation to verify the primary structure of a recombinant product sequence and to monitor post-translational modifications (PTMs). Although proteolytic digestion has been used for decades, it remains a labour-intensive procedure that can be challenging to accurately reproduce. Here, we describe a fast and reproducible protocol for protease digestion that is automated using immobilised trypsin on magnetic beads, which has been incorporated into an optimised peptide mapping workflow to show method transferability across laboratories. The complete workflow has the potential for use within a multi-attribute method (MAM) approach in drug development, production and QC laboratories. The sample preparation workflow is simple, ideally suited to inexperienced operators and has been extensively studied to show global applicability and robustness for mAbs by performing sample digestion and LC-MS analysis at four independent sites in Europe. LC-MS/MS along with database searching was used to characterise the protein and determine relevant product quality attributes (PQAs) for further testing. A list of relevant critical quality attributes (CQAs) was then established by creating a peptide workbook containing the specific mass-to-charge (m/z) ratios of the modified and unmodified peptides of the selected CQAs, to be monitored in a subsequent test using LC-MS analysis. Data is provided that shows robust digestion efficiency and low levels of protocol induced PTMs. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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6. Development of a HS-SPME-GC-MS method for the analysis of phthalates in glycerin and liquid paraffin: application to safety evaluation of cosmetic packagings.
- Author
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Murat, Pauline, Ferret, Pierre-Jacques, Coslédan, Sylvie, and Simon, Valérie
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PHTHALATE esters ,PARAFFIN wax ,GLYCERIN ,LIQUID-liquid extraction ,PLASTICS in packaging ,EXTRACTION techniques ,SOLID phase extraction - Abstract
Migration of molecules from packaging into products is a well-known phenomenon of which the studies in the food and medical industries are regulated in Europe by several legislations. However, for cosmetic packagings, there is no protocol nor specific migration limits available. The objective of this work was to use glycerin and liquid paraffin as cosmetic product simulants to perform a safety assessment on phthalates in 11 plastic packagings used in the cosmetic industry. To study these compounds in the matrices, 2 extraction techniques were compared: liquid-liquid extraction and solid-phase microextraction (SPME). The optimization of the 2 processes of extraction showed that SPME was more adapted to the study. Finally, samples of glycerin and liquid paraffin were analyzed by a SPME-GC-MS method to quantitate 10 regulated phthalates. In glycerin, only DEP was quantitated above the LOQ in 3 packagings, but the concentrations measured were under the set concentration threshold of 0.5 ppm. In liquid paraffin, DEP was quantitated above this concentration threshold. A safety evaluation was so performed by calculating the systemic exposure damage, and the results were finally considered to be safe for consumers. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
7. Single-particle speciation of alkylamines in ambient aerosol at five European sites.
- Author
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Healy, Robert, Evans, Greg, Murphy, Michael, Sierau, Berko, Arndt, Jovanna, McGillicuddy, Eoin, O'Connor, Ian, Sodeau, John, and Wenger, John
- Subjects
ALKYLAMINES ,ATMOSPHERIC aerosol analysis ,CHEMICAL speciation ,TRIETHYLAMINE ,DIPROPYLAMINE ,DIMETHYLAMINE ,TIME-of-flight mass spectrometry - Abstract
Alkylamines are associated with both natural and anthropogenic sources and have been detected in ambient aerosol in a variety of environments. However, little is known about the ubiquity or relative abundance of these species in Europe. In this work, ambient single-particle mass spectra collected at five sampling sites across Europe have been analysed for their alkylamine content. The aerosol time-of-flight mass spectrometer (ATOFMS) data used were collected in Ireland (Cork), France (Paris, Dunkirk and Corsica) and Switzerland (Zurich) between 2008 and 2013. Each dataset was queried for mass spectral marker ions associated with the following ambient alkylamines: dimethylamine (DMA), trimethylamine (TMA), diethylamine (DEA), triethylamine (TEA), dipropylamine (DPA) and tripropylamine (TPA). The fraction of ambient particles that contained detectable alkylamines ranged from 1 to 17 % depending on location, with the highest fractions observed in Paris and Zurich in the winter months. The lowest fractions were observed at coastal sites, where the influence of animal husbandry-related alkylamine emissions is also expected to be lowest. TMA was the most ubiquitous particle phase alkylamine detected and was observed at all locations. Alkylamines were found to be internally mixed with both sulphate and nitrate for each dataset, suggesting that aminium salt formation may be important at all sites investigated. Interestingly, in Corsica, all alkylamine particles detected were also found to be internally mixed with methanesulphonic acid (MSA), indicating that aminium methanesulphonate salts may represent a component of marine ambient aerosol in the summer months. Internal mixing of alkylamines with sea salt was not observed, however. Alkylamine-containing particle composition was found to be reasonably homogeneous at each location, with the exception of the Corsica and Dunkirk sites, where two and four distinct mixing states were observed, respectively. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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8. Basic mathematics and physics for undergraduate chemistry students according to the Eurobachelor® curriculum.
- Author
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Andersen, Jens, Burns, D., and Hu, P.
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ANALYTICAL chemistry ,STUDENTS ,PHYSICS education ,ASSOCIATIONS, institutions, etc. ,GEOMETRY education - Abstract
The article reports on the curriculum for the bachelor degree suggested by the European Association for Chemical and Molecular Science Division of Analytical Chemistry (EuCheMS-DAC). It states that many students are often lacking in the physics of classical mechanics and optics, of which some requires familiarity with aspects of geometry. It also discusses the concepts of physics which are important in teaching analytical chemistry.
- Published
- 2012
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9. Stable isotope dilution assay for the accurate determination of mycotoxins in maize by UHPLC-MS/MS.
- Author
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Varga, Elisabeth, Glauner, Thomas, Köppen, Robert, Mayer, Katharina, Sulyok, Michael, Schuhmacher, Rainer, Krska, Rudolf, and Berthiller, Franz
- Subjects
MYCOTOXINS ,ACETONITRILE ,HIGH performance liquid chromatography ,MYCOTOXICOSES ,CORN - Abstract
A fast, easy-to-handle and cost-effective analytical method for 11 mycotoxins currently regulated in maize and other cereal-based food products in Europe was developed and validated for maize. The method is based on two extraction steps using different acidified acetonitrile-water mixtures. Separation is achieved using ultrahigh-performance liquid chromatography (UHPLC) by a linear water-methanol gradient. After electrospray ionisation, tandem mass spectrometric detection is performed in dynamic multiple reaction monitoring mode. Since accurate mass spectrometric quantification is hampered by matrix effects, uniformly [C]-labelled mycotoxins for each of the 11 compounds were added to the sample extracts prior to UHPLC-MS/MS analysis. Method performance parameters were obtained by spiking blank maize samples with mycotoxins before as well as after extraction on six levels in triplicates. The twofold extraction led to total recoveries of the extraction steps between 97% and 111% for all target analytes, including fumonisins. The [C]-labelled internal standards efficiently compensated all matrix effects in electrospray ionisation, leading to apparent recoveries between 88% and 105% with reasonable additional costs. The relative standard deviations of the whole method were between 4% and 11% for all analytes. The trueness of the method was verified by the measurement of several maize test materials with well-characterized concentrations. In conclusion, the developed method is capable of determining all regulated mycotoxins in maize and presuming similar matrix effects and extraction recovery also in other cereal-based foods. [ABSTRACT FROM AUTHOR]
- Published
- 2012
- Full Text
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10. Sr isotope measurements in beef-analytical challenge and first results.
- Author
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Rummel, S., Dekant, C., Hölzl, S., Kelly, S., Baxter, M., Marigheto, N., Quetel, C., Larcher, R., Nicolini, G., Fröschl, H., Ueckermann, H., and Hoogewerff, J.
- Subjects
STRONTIUM ,CATTLE ,PROTEINS ,MEAT ,FREEZE-drying - Abstract
The strontium isotope ratio (Sr/Sr) in beef, derived from 206 European cattle, has been measured. These cattle were located in 12 different European regions within France, Germany, Greece, Ireland, Italy, Spain and the UK. As animal protein is known to be a difficult material on which to conduct Sr isotope analysis, several investigations were undertaken to develop and improve the sample preparation procedure. For example, Sr isotope analysis was performed directly on freeze-dried meat and defatted dry mass from the same samples. It was found that enormous differences-sometimes exceeding the measurement uncertainty-could occur between the fractions and also within one sample even if treated in the same manner. These variations cannot be definitely allocated to one cause but are most likely due to inhomogeneities caused by physiological and biochemical processes in the animals as post mortem contamination during analytical processing could be excluded. For further Sr isotope measurements in meat, careful data handling is recommended, and for the authentic beef samples within this project, it was decided to use only freeze-dried material. It can be demonstrated, however, that Sr isotope measurements in beef proteins are a valuable tool for authentication of geographic origin. Although partly overlapping, some of the European sampling sites could be discriminated even by only using Sr/Sr. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]
- Published
- 2012
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11. An ultra-sensitive online SPE-LC-MS/MS method for the quantification of levonorgestrel released from intrauterine devices.
- Author
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Moser, Christina, Gschließer, Andreas, Mattle, Verena, Wildt, Ludwig, Griesmacher, Andrea, and Seger, Christoph
- Subjects
LEVONORGESTREL intrauterine contraceptives ,MEDICATED intrauterine contraceptives ,CONTRACEPTIVES ,TANDEM mass spectrometry - Abstract
selective and sensitive liquid chromatography-tandem mass spectrometry method for the determination of very low levonorgestrel ( d-(−)-norgestrel) serum levels such as those found in patients using levonorgestrel-releasing intrauterine devices (IUDs) was developed. To achieve the sub-nanomolar sensitivity needed to measure such serum levels, a diethyl ether extraction sample preparation protocol was applied prior to the online solid-phase extraction-liquid chromatography-tandem mass spectrometry (SPE-LC-MS/MS) assay. Analyte quantification from the selected reaction monitoring experiments relied on the use of sixfold deuterated norgestrel as internal standard. The final method was linear up to 1.50 ng/ml with a lower limit of quantification (LLOQ) of 0.05 ng/ml. It was found to be precise and accurate with imprecision <8% and bias <6% assessed at three control levels. Total analyte recovery measured in patient pools at three concentration levels was found to exceed 92%. Matrix interferences were excluded by post-column analyte infusion experiments. As a proof of concept, a set of IUD patient serum samples was screened for their levonorgestrel content. A total of 97.5% ( n = 94) of the samples did show serum levels exceeding the LLOQ, proving the applicability of the assay in relevant clinical cohorts. This method must not be used for diagnostic or therapeutic purposes, since it did not undergo formal performance evaluation in the sense of the in vitro diagnostic directive (98/79/EG) of the European community. [ABSTRACT FROM AUTHOR]
- Published
- 2011
- Full Text
- View/download PDF
12. Ancient and historic steel in Japan, India and Europe, a non-invasive comparative study using thermal neutron diffraction.
- Author
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Grazzi, F., Civita, F., Williams, A., Scherillo, A., Barzagli, E., Bartoli, L., Edge, D., and Zoppi, M.
- Subjects
STEEL ,NEUTRON diffraction ,OPTICAL diffraction - Abstract
The production and refinement of steel has followed very different paths in different parts of the Eurasian continent. In aiming to characterize the similarities and differences between various smelting and smithing methods, we have analysed steel samples from four different areas and historic periods: the Kotō Age in Japan (twelfth-sixteenth century), the Moghul Empire in India (seventeenth-nineteenth century), the Ottoman Turkish Empire (seventeenth century) and the late Middle Ages (fifteenth century) in Italy. The best quality steel was employed for forging arms and armour of high quality, so that we have selected samples from Japan, India, the Middle East and Italy belonging to such a category. Traditional methods, such as metallography, used to characterize different steels in terms of their carbon contents, microconstituents and slag inclusions, entailed an invasive approach. Since many of the selected artefacts are in a very good state of conservation, a different and non-invasive approach was desirable. To this aim, we have used time of flight neutron diffraction on the Italian Neutron Experimental Station diffractometer, located at the pulsed neutron source ISIS in the United Kingdom. By this technique, we were able to quantify the phase distribution of the metal phases, the slag inclusion content, and the oxidation state of the samples, both as average concentration on the whole artefact and in selected gauge volumes. The results of the present investigation offer an interesting picture of the steel metallurgy in different areas of the world. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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- View/download PDF
13. The development of a rapid method for the isolation of four azaspiracids for use as reference materials for quantitative LC–MS–MS methods.
- Author
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Canás, Isa Ruppen, O'Callaghan, Keith, Moroney, Cian, Hamilton, Brett, James, Kevin J., and Furey, Ambrose
- Subjects
TOXINS ,POLYETHERS ,SHELLFISH ,QUADRUPOLES - Abstract
The azaspiracids are a family of lipophilic polyether marine biotoxins that have caused a number of human intoxication incidents in Europe since 1995 after consumption of contaminated shellfish ( Mytilus edulis). Levels of azaspiracids in shellfish for human consumption are monitored in accordance with EU guidelines: only shellfish with less than 160 μg kg are deemed safe. The limited availability of commercially available standards for azaspiracids is a serious problem, because validated LC–MS methods are required for routine analysis of these toxins in shellfish tissues. The procedure described herein has been used for the separation and the isolation of four azaspiracid (AZA) toxins from shellfish, for use as LC–MS–MS reference materials. Five separation steps have been used to isolate azaspiracids 1, 2, 3, and 6. The purity of the toxins obtained has been confirmed by multiple mass spectrometric methods using authentic azaspiracid standards. The same techniques have been used for quantification of the toxins extracted. The isolation procedure involves several chromatographic purification techniques: solid-phase extraction (diol sorbent, 90% mass reduction, and 95 ± 1% toxin recovery); Sephadex size-exclusion chromatography (87% mass reduction and up to 95 ± 2% toxin recovery), Toyopearl HW size-exclusion chromatography (90% mass reduction and up to 92.5 ± 2.5% toxin recovery), and semi-preparative LC (78 ± 3% toxin recovery). The procedure effectively separates the toxins from the sample matrix and furnishes azaspiracid toxins (AZA1, AZA2, AZA3 and AZA6) of sufficient purity with an average yield of 65% ( n = 5). Triple-quadrupole mass spectrometry was used for qualitative and quantitative monitoring of the isolation efficiency after each stage of the process. High-resolution mass spectrometric evaluation of the toxic isolated material in both positive and negative modes suggests high purity. [ABSTRACT FROM AUTHOR]
- Published
- 2010
- Full Text
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14. Master programs in analytical chemistry.
- Author
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Salzer, Reiner
- Subjects
BOLOGNA process (European higher education) ,HIGHER education ,ANALYTICAL chemistry education ,ACADEMIC degrees ,SCHOOL credits - Abstract
This article summarizes the current status of the Bologna Process emphasizing analytical chemistry. Chemical spills and multiple chemical sensitivity are two job opportunities that can be associated with analytical chemistry. Particular focus is given to the objectives of the Budapest Descriptor Master degrees in chemistry, along with the aims of the Euromaster qualification. There are 120 European Credit Transfer and Accummulation System (ECTS) credits in a Chemistry Euromaster program.
- Published
- 2009
- Full Text
- View/download PDF
15. European analytical column No. 36 (January 2008).
- Author
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Karlberg, Bo, Emons, Hendrik, and Andersen, Jens E. T.
- Subjects
ANALYTICAL chemistry ,CHEMICAL literature ,ASSOCIATIONS, institutions, etc. - Abstract
The article presents updates related to analytical chemistry in Europe. The European Analytical Column will be inviting guest columnists who will give his or her opinion on issues related to analytical chemistry in the region. Hendrik Emons, professor at the Institute for Reference Materials and Measurements (IRMM), says the demand for information regarding the interrelations of chemical composition-structure-properties are abundant. Heiner Korte resigned as Secretary for the Division of Analytical Chemistry (DAC).
- Published
- 2008
- Full Text
- View/download PDF
16. Regulations relating to mycotoxins in food.
- Author
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Van Egmond, Hans P., Schothorst, Ronald C., and Jonker, Marco A.
- Subjects
MYCOTOXINS ,TOXICOLOGY ,FOOD ,TRADE regulation ,DECISION making - Abstract
Regulations relating to mycotoxins have been established in many countries to protect the consumer from the harmful effects of these compounds. Different factors play a role in the decision-making process of setting limits for mycotoxins. These include scientific factors, for example the availability of toxicological data and occurrence data, detailed knowledge about possibilities for sampling and analysis, and socio-economic issues. By the end of 2003, approximately 100 countries (covering approximately 85% of the world’s inhabitants) had specific regulations or detailed guidelines for mycotoxins in food. The regulations were related to aflatoxins (B
1 , B2 , G1 and G2 ), aflatoxin M1 , trichothecenes (deoxynivalenol, diacetoxyscirpenol, T-2 toxin and HT-2 toxin), fumonisins (B1 , B2 , and B3 ), agaric acid, ergot alkaloids, ochratoxin A, patulin, phomopsins, sterigmatocystin, and zearalenone. In Europe, and in particular in the EU, regulatory and scientific interest in mycotoxins has undergone a development in the last decade from autonomous national activity towards more EU-driven activity with a structural and network character. Harmonized EU limits now exist for 40 mycotoxin–food combinations. It is expected this number will grow in 2007 to approximately 50. The direct or indirect influence of European organizations and programs on the EU mycotoxin regulatory developments is significant. They include the European Food Safety Authority, the Scientific Cooperation on Questions relating to Food, the Rapid Alert System for Food and Feed, the creation of an EU Community Reference Laboratory for Mycotoxins and a mandate of the EC to the European Standardization Committee in methods for analysis for mycotoxins in food. Large pan-European research and networking projects as “BioCop” and “MoniQA” are also important. [ABSTRACT FROM AUTHOR]- Published
- 2007
- Full Text
- View/download PDF
17. Teaching chemistry in Europe—a look at future developments.
- Author
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Barbosa, J., Guiteras, J., and Fonrodona, G.
- Subjects
CHEMISTRY education ,TEACHING ,STUDENTS ,TEACHERS ,ACADEMIC degrees - Abstract
The article presents a look at future developments in teaching chemistry in Europe. In the near future the teaching of chemistry in Europe will be affected by a series of fundamental changes arising from adoption of common European teaching goals and of a European credit-transfer system. It is well known that the final objective is to produce a system in which equivalent and readily comparable degrees are awarded within Europe, to facilitate the mobility of students and teachers and to make the recognition of degrees easier.
- Published
- 2004
- Full Text
- View/download PDF
18. Diversity and comparability—towards a common European Higher Education Area.
- Author
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Vogel, Martin
- Subjects
COLLEGE curriculum ,EDUCATIONAL change ,MULTICULTURALISM ,ACADEMIC degrees ,CURRICULUM change ,UNIVERSITIES & colleges - Abstract
The author reflects on the impact of diverse European culture on the Europe's higher education area. The author refers to the Bologna Declaration to establish a common European higher education area by 2010 and various positive outcomes of the declaration on the overall higher education system of Europe including introduction of bachelor and master degree system. The author also discusses the common chemistry curriculum in Europe and stresses more governmental support for the success.
- Published
- 2007
- Full Text
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19. ERM - A new landmark for reference materials.
- Author
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Emons, Hendrik, Marriott, John, and Matschat, Ralf
- Subjects
REFERENCE sources ,INFORMATION resources ,INFORMATION science ,ANALYTICAL chemistry - Abstract
Reports on the creation of the European Reference Material (ERM) by a group of European producers of certified reference materials (CRM). Developments in the use of CRMs; Factors to be considered in selecting a CRM for an analytical laboratory; Principles of the ERM initiative.
- Published
- 2005
- Full Text
- View/download PDF
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