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McSAS3 is a refactored software package for fitting large batches of (X-ray or Neutron) scattering data. It uses a Monte-Carlo acceptance-rejection algorithm to optimize model parameters - ideal for analysis of size-disperse scatterers.
The refactored code can exploit multiprocessing, traceably stores (multiple) results in the output file, and allows for re-histogramming of previous optimizations. Besides analysis of large batches, it can also be integrated in automated data processing pipelines.
The live demonstration will show how to use the software, what its limitations are, and what outcomes can look like for batches of results.
Efforts are rising in opening up science by making data more transparent and more easily available, including the data reduction and evaluation procedures and code. A strong foundation for this is the F.A.I.R. principle, building on Findability, Accessibility, Interoperability, and Reuse of digital assets, complemented by the letter T for trustworthyness of the data. Here, we have used data, which was made available by the Institute Laue-Langevin and can be identified using a DOI, to follow the F.A.I.R.+T. principle in extracting, evaluating and publishing triple axis data, recorded at IN3.
Safe food is a prerequisite for good human health, however currently almost one in ten people in the world fall ill after eating contaminated food. National food safety authorities need to be able to manage food safety risks along the entire food chain. The Official Controls Regulation (EU) 2017/625 was put in place to ensure that food and feed law stipulates the need for validated analytical methods. However, whilst method development for food control and proficiency testing are well established by European Union Reference Laboratories and National Reference Laboratories, validation of the measurements involved, certified reference materials and internationally recognised calibration and measurement capabilities are currently often (?) lacking. This may erode trust in the accuracy of the measurements.
This poster presents Food-MetNet, a coordinated preparatory initiative to establish the European Metrology Network for Safe and Sustainable Food, recently approved by the European Association of National Metrology Institutes (EURAMET). Food-MetNet aims to establish an ongoing dialogue between the metrology community, reference laboratories and regulatory bodies, in order to (i) identify stakeholders’ needs, (ii) develop a sustainable knowledge-sharing programme and web-based platform for stakeholders and (iii) develop roadmaps and a strategic research agenda. Improved access to more reliable and accurate food safety measurements will enable reference laboratories to more confidently and effectively compare their measurement results and support accreditation. This is particularly important where national food safety authorities need to assess potential new contaminants, novel food ingredients and newly emerging food risks, and new measurements methods may be required as well as input into new documentary standards. The activities for sustainable food intend to boost the activity within the "EU green deal framework" to reduce food waste and losses, and the development of standards and methods that allow for the reuse of food waste. The support to new business opportunities and innovation will allow increasing the market competitiveness of EU food industries and the valorisation of waste by reducing environmental impacts.
Current trends in materials and life sciences are flanked by the need to push detection limits to single molecules or single cells, enable the characterization of increasingly complex matrices or sophisticated nanostructures, speed up the time of analysis, reduce instrument complexity and costs, and improve the reliability of data. This requires suitable analytical tools such as spectroscopic, separation and imaging techniques, mass spectrometry, and hyphenated techniques as well as sensors and their adaptation to application-specific challenges in the environmental, food, consumer product, health sector, nanotechnology, and bioanalysis. Increasing concerns about health threatening known or emerging pollutants in drinking water, consumer products, and food and about the safety of nanomaterials led to a new awareness of the importance of analytical sciences. Another important driver in this direction is the increasing demand by legislation, particularly in view of the 17 sustainable development goals by the United Nations addressing clean energy, industry, and innovation, sustainable cities, clean water, and responsible consumption and production. In this respect, also the development of analytical methods that enable the characterization of material flows in production processes and support recycling concepts of precious raw materials becomes more and more relevant. In the future, this will provide the basis for greener production in the chemical industry utilizing recycled or sustainable starting materials.
This makes analytical chemistry an essential player in terms of the circular economy helping to increase the sustainability of production processes. In the life sciences sector, products based on proteins, such as therapeutic and diagnostic antibodies, increase in importance. These increasingly biotechnologically produced functional biomolecules pose a high level of complexity of matrix and structural features that can be met only by highly advanced methods for separation, characterization, and detection. In addition, metrological traceability and target definition are still significant challenges for the future, particularly in the life sciences.
However, innovative reference materials as required for the health and food sector and the characterization of advanced materials can only be developed when suitable analytical protocols are available. The so-called reproducibility crisis in sciences underlines the importance of improved measures of quality control for all kinds of measurements and material characterization. This calls for thorough method validation concepts, suitable reference materials, and regular interlaboratory comparisons of measurements as well as better training of scientists in analytical sciences.
The important contribution of analytical sciences to these developments is highlighted by a broad collection of research papers, trend articles, and critical reviews from these different application fields. Special emphasis is dedicated to often-overlooked quality assurance and reference materials.
Current trends in materials and life sciences are flanked by the need to push detection limits to single molecules or single cells, enable the characterization of increasingly complex matrices or sophisticated nanostructures, speed up the time of analysis, reduce instrument complexity and costs, and improve the reliability of data. This requires suitable analytical tools such as spectroscopic, separation and imaging techniques, mass spectrometry, and hyphenated techniques as well as sensors and their adaptation to application-specific challenges in the environmental, food, consumer product, health sector, nanotechnology, and bioanalysis. Increasing concerns about health threatening known or emerging pollutants in drinking water, consumer products, and food and about the safety of nanomaterials led to a new awareness of the importance of analytical sciences. Another important driver in this direction is the increasing demand by legislation, particularly in view of the 17 sustainable development goals by the United Nations addressing clean energy, industry, and innovation, sustainable cities, clean water, and responsible consumption and production. In this respect, also the development of analytical methods that enable the characterization of material flows in production processes and support recycling concepts of precious raw materials becomes more and more relevant. In the future, this will provide the basis for greener production in the chemical industry utilizing recycled or sustainable starting materials.
This makes analytical chemistry an essential player in terms of the circular economy helping to increase the sustainability of production processes. In the life sciences sector, products based on proteins, such as therapeutic and diagnostic antibodies, increase in importance. These increasingly biotechnologically produced functional biomolecules pose a high level of complexity of matrix and structural features that can be met only by highly advanced methods for separation, characterization, and detection. In addition, metrological traceability and target definition are still significant challenges for the future, particularly in the life sciences.
However, innovative reference materials as required for the health and food sector and the characterization of advanced materials can only be developed when suitable analytical protocols are available. The so-called reproducibility crisis in sciences underlines the importance of improved measures of quality control for all kinds of measurements and material characterization. This calls for thorough method validation concepts, suitable reference materials, and regular interlaboratory comparisons of measurements as well as better training of scientists in analytical sciences.
The important contribution of analytical sciences to these developments is highlighted by a broad collection of research papers, trend articles, and critical reviews from these different application fields. Special emphasis is dedicated to often-overlooked quality assurance and reference materials.
Polycarboxylate ethers (PCEs) are widely used in construction, but the exact nature of their interaction with cement is still debated. Aiming at a better understanding of the role of tricalcium Aluminate (C3A) in cement hydration, we assessed the potential of optical spectroscopy in combination with a water-soluble fluorescent organic reporter dye (S0586) to monitor the early hydration of C3A in the presence of 26 wt% CaSO4.2H2O (C3A26G-S) with and without PCE. As optical methods, steady-state fluorescence and diffuse reflectance (UV–VisDR) spectroscopy were employed. Phase characterization and particle size distribution were performed with in-situ X-ray diffraction (in-situ XRD) and dynamic light scattering (DLS). Our results show that fluorescence and UV–VisDR spectroscopy can be used to monitor the formation of metastable phases by the disaggregation of the dye S0586 in a cement paste as well as changes in ettringite formation. Addition of PCE slowed down the disaggregation of the dye as reflected by the corresponding changes of the dyes absorption and fluorescence. This prolonged induction period is a well-known side effect of PCEs and agrees with previous reported calorimetric studies and the Inhibition of gypsum dissolution observed by in-situ XRD. This demonstrates that fluorescence and UV–VisDR spectroscopy together with a suitable optical probe can provide deeper insights into the influence of PCE on C3A-gypsum hydration which could be e.g., utilized as screening method for comparing the influences
of different types of PCEs.
Dataset and Jupyter worksheet interpreting the (results from) small- and wide-angle scattering data from a series of boehmite/epoxy nanocomposites. Accompanies the publication "Competition of nanoparticle-induced mobilization and immobilization effects on segmental dynamics of an epoxy-based nanocomposite", by Paulina Szymoniak, Brian R. Pauw, Xintong Qu, and Andreas Schönhals.
Datasets are in three-column ascii (processed and azimuthally averaged data) from a Xenocs NanoInXider SW instrument. Monte-Carlo analyses were performed using McSAS 1.3.1, other analyses are in the Python 3.7 worksheet. Graphics and result tables are output by the worksheet.
Tire wear particles (TW) are generated by the abrasions of tires on the road surface through traffic. These particles can be transported by air and surface runoff and might also infiltrate the soil and consequently affect terrestrial ecosystems. The estimated tire wear (TW) emissions are immense, with 1.33 106 t a-1 in Europe. Despite this, only little is known about the environmental contents or the fate of TW.
One reason for this knowledge gap is the challenging analysis of TW in environmental samples. Detection of TW with spectroscopic methods is problematic due to high fluorescence interferences caused by contained black carbon. One analytical approach is to use zinc (Zn), a typical additive in tires, as a specific marker for the quantification of tire wear. However, any Zn originating from the sample matrix must be separated beforehand and requires elaborate sample preparation.
Car tires consist partly of synthetic rubbers, such as styrene-butadiene-rubber (SBR). This SBR could be identified and quantified via Thermal-Extraction-Desorption-Gas Chromatography-Mass Spectrometry (TED-GC-MS). This newly developed and fast screening method allows the simultaneous detection of microplastics and TW mass contents and requires minimal to no sample preparation. Firstly the sample is thermally extracted in a thermobalance under a nitrogen atmosphere. The resulting specific decomposition products are sorbed on a solid phase adsorber, which is then transferred to a GC-MS via an autosampler, where the products are desorbed, separated and identified. Cyclohexenylbenzene is used as a specific marker for SBR.
Here we investigated top layer soil samples, collected at the roadside of highly frequented German highways. Samples were analyzed without sample preparation, and SBR was detected in all investigated samples in mass contents ranging from 67.2 to 2230 mg kg-1. A correlation between SBR and Zn content in the soil was confirmed, while the correlation between SBR and Corg was hardly pronounced. We successfully demonstrated the application of TED-GC-MS as a screening method for tire wear in soil samples.
The present study will discuss these analytical results in detail as well as sampling parameters like sampling depth and distance to the roadside, and the effect of the particle size on the particle transport by water runoff and air.
Background: The ubiquitous occurrence of microplastic particles in marine and aquatic ecosystems was intensively investigated in the past decade. However, we know less about the presence, fate, and input paths of microplastic in terrestrial ecosystems. A possible entry path for microplastic into terrestrial ecosystems is the agricultural application of sewage sludge and solid bio-waste as fertilizers. Microplastic contained in sewage sludge also includes Polyethylene terephthalate (PET), which could originate as fiber from textile products or as a fragment from packaging products (foils, bottles, etc.). Information about microplastic content in such environmental samples is limited yet, as most of the used analytical methods are very time-consuming, regarding sample preparation and detection, require sophisticated analytical tools and eventually need high user knowledge.
Results: Here, we present a simple, specific tool for the analysis of PET microplastic particles based on alkaline extraction of PET from the environmental matrix and subsequent determination of the monomers, terephthalic acid, using liquid chromatography with UV detection (LC-UV). The applicability of the method is shown for different types of PET in several soil-related, terrestrial environmental samples, e.g., soil, sediment, compost, fermentation residues, but also sewage sludge, suspended particles from urban water management systems, and indoor dust. Recoveries for model samples are between 94.5 and 107.1%. Limit of determination and limit of quantification are absolute masses of 0.031 and 0.121 mg PET, respectively. In order to verify the measured mass contents of the environmental samples, a method comparison with thermal extraction-desorption-gas chromatography–mass spectrometry (TED-GC/MS) was conducted. Both methods deliver similar results and corroborated each other. PET mass contents in environmental samples range from values below LOQ in agriculture soil up to 57,000 mg kg−1 in dust samples.
Conclusions: We demonstrate the potential of an integral method based on chemical extraction for the Determination of PET mass contents in solid environmental samples. The method was successfully applied to various matrices and may serve as an analytical tool for further investigations of PET-based microplastic in terrestrial ecosystems.
The TED-GC-MS analysis is a two-step method. A sample is first decomposed in a thermogravimetric analyzer (TGA) and the gaseous decomposition products are then trapped on a solid-phase adsorber. Subsequently, the solid-phase adsorber is analyzed with thermal desorption gas chromatography mass spectrometry (TDU-GC-MS). This method is ideally suited for the analysis of polymers and their degradation processes. Here, a new entirely automated System is introduced which enables high sample throughput and reproducible automated fractioned collection of decomposition products. Strengths and limitations of the system configuration are elaborated via three examples focused on practical challenges in materials analysis and identification: i) separate analysis of the components of a wood-plastic-composite material, ii) quantitative determination of weight concentration of the constituents of a polymer blend and iii) quantitative analysis of model samples of microplastics in suspended particulate matter.
While plastics have become indispensable in our daily lives over the last decades, the input into the environment has been increasing concurrently. Plastics often end up in the environment because of intensive use and poor waste management practice. They are subjected to aging and fragmentation and finally be deposited as microplastic particles or in short microplastics (MP). MP are defined as particles originating from synthetic polymers between 1 µm and 5 mm.
Although the pervasive abundance of MP in aquatic environments has been demonstrated comprehensively, less is known about the occurrence and fate of MP in terrestrial ecosystems. It is still unclear if soil functions as a MP source or a sink for aquatic environments. MP can either be transported into water bodies by soil erosion or be retained in soils. The few studies published are not comparable because of non-existent harmonized and standardized methods for sampling, sample preparation, and analysis.
For an assessment of a potential exposure situation of MP, the determination of a mass content in the soil is crucial. Consequently, spectroscopic methods like Raman or FTIR are not suitable, as they deliver information about the shape and size of individual particles. Therefore, we show the application of ThermoExtractionDesorption-GasChromatography-MassSpectrometry (TED-GC-MS) for MP analysis in the soil. In this method, the soil sample is heated up to 600 °C in a nitrogen atmosphere. The decomposition gases are sorbed on a solid phase, then transferred to a GS-MS system where they are desorbed, separated and identified. The method allows the rapid identification of individual polymers through the detection of specific decomposition products, but also the quantitative determination of the MP mass. Besides thermoplastics, elastomers originated from tire abrasion, can be detected.
In the present study, several terrestrial ecosystems in south-west Germany were systematically sampled. Subsequent sample preparation included sieving in fractions of 5-100 µm, 100-1000 µm, and 1-5 mm. MP were extracted by density separation using ZnCl2 solutions. The detection was done by TED-GC-MS measurements. Data of agricultural areas and floodplains are presented exemplarily. A quantitative assessment of highly occurring MP from littering as well as tire abrasion is conducted.
The accumulation of plastics leaked into the environment achieve a high perception in the last years. It is uncontroversial that often an uncontrolled, high consumption of plastic products and a poor waste management resulted in plastic findings all over in the environment. However, less is known about the relevant pathways and fate of plastic in the environment. Especially plastic fragments smaller 5 mmm, so called microplastics, achieve a high attention, because their amount and risks arising from these fragments are still unknown. The basic mechanisms of plastic or more precise, of different polymer degradation processes are often not considered, resulting in unrealistic statements.
For generation of fundamental understanding of this problem we developed in the last years a fast thermoanalytical method for identification and mass quantification of microplastics in complex samples. The presentation will also give a short introduction about polymer degradation.
The presence, fate and effects of microplastics (MP) in terrestrial systems are largely unknown. The few existing studies investigated either agricultural or industrial sites. Several techniques were used for analysis, primarly spectroscopic methods such as FTIR or Raman. Sample pretreatments like density separations are common to reduce matrix. A lack of harmonised and standardised sampling instructions for microplastic investigations in the terrestrial area was identified as particular critical, because different studies are barely comparable.
The aim of the project is to develop a proposal for a harmonized procedure for sampling, sample preparation and the detection of microplastics in terrestrial matrices for total content determination. By detecting specific degradation products the thermal extraction desorption gas chromatography mass spectrometry (TED-GC-MS) allows a direct determination of mass content of MP in environmental samples.
BAM is the German Federal Institute for Materials Research and Testing and the competent authority for mechanical and thermal safety assessment of transport packages for spent fuel and high level waste. In context with safety assessment of RAM packages BAM performed numerous drop tests in the last decades. The tests were mostly accompanied by extensive and various measurement techniques especially by instrumented measurements with strain gages and accelerometers.
The procedure of drop testing and the resulting measurement analysis are the main methods to evaluate the safety against mechanical test conditions. Measurement techniques are dedicated to answer questions in regard to the structural integrity of a RAM package, the mechanical behavior of the prototype as well as of its content under impact conditions.
Test results like deceleration-time functions constitute a main basis for the validation of assumptions in the safety analysis and for the evaluation of numerical calculations. In this context the adequate selection of accelerometers and measurement systems for the performance of drop tests is important. Therefore it is not only necessary to find suitable positions for the accelerometers at the test specimens, but also to consider technical boundary conditions as e.g. temperature.
BAM is the German Federal Institute for Materials Research and Testing and the competent authority for mechanical and thermal safety assessment of transport packages for spent fuel and high level waste. In context with safety assessment of RAM packages BAM performed numerous drop tests in the last decades. The tests were mostly accompanied by extensive and various measurement techniques especially by instrumented measurements with strain gages and accelerometers.
The procedure of drop testing and the resulting measurement analysis are the main methods to evaluate the safety against mechanical test conditions. Measurement techniques are dedicated to answer questions in regard to the structural integrity of a RAM package, the mechanical behavior of the prototype as well as of its content under impact conditions.
Test results like deceleration-time functions constitute a main basis for the validation of assumptions in the safety analysis and for the evaluation of numerical calculations. In this context the adequate selection of accelerometers and measurement systems for the performance of drop tests is important. Therefore it is not only necessary to find suitable positions for the accelerometers at the test specimens, but also to consider technical boundary conditions as e.g. temperature.
Methodologies on fire risk analysis in road tunnels consider numerous factors affecting risks (risk indicators) and express the results by risk measures. But only few comprehensive studies on effects of risk indicators on risk measures are available. For this reason, this study quantifies the effects and highlights the most important risk indicators with the aim to Support further developments in risk analysis. Therefore, a system model of a road tunnel was developed to determine the risk measures.
The system model can be divided into three parts: the fire part connected to the fire model Fire Dynamics Simulator (FDS); the evacuation part connected to the evacuation model FDS+Evac; and the frequency part connected to a model to calculate the frequency of fires. This study shows that the parts of the system model (and their most important risk indicators) affect the risk measures in the following order: first, fire part (maximum heat release rate); second, evacuation part (maximum preevacuation time); and, third, frequency part (specific frequency of fire). The plausibility of These results is discussed with view to experiences from experimental studies and past fire incidents.
Conclusively, further research can focus on these most important risk indicators with the aim to optimise risk analysis.
Methodologies on fire risk analysis in road tunnels consider numerous factors affecting risks (risk indicators) and express the results by risk measures. But only few comprehensive studies on effects of risk indicators on risk measures are available. For this reason, this study quantifies the effects and highlights the most important risk indicators with the aim to Support further developments in risk analysis. Therefore, a system model of a road tunnel was developed to determine the risk measures.
The system model can be divided into three parts: the fire part connected to the fire model Fire Dynamics Simulator (FDS); the evacuation part connected to the evacuation model FDS+Evac; and the frequency part connected to a model to calculate the frequency of fires. This study shows that the parts of the system model (and their most important risk indicators) affect the risk measures in the following order: first, fire part (maximum heat release rate); second, evacuation part (maximum preevacuation time); and, third, frequency part (specific frequency of fire). The plausibility of These results is discussed with view to experiences from experimental studies and past fire incidents.
Conclusively, further research can focus on these most important risk indicators with the aim to optimise risk analysis.
Towards the standardization of biochar analysis: the COST action TD1107 interlaboratory comparison
(2016)
Biochar produced by pyrolysis of organic residues is increasingly used for soil amendment and many other applications. However, analytical methods for its physical and chemical characterization are yet far from being specifically adapted, optimized, and standardized. Therefore, COST Action TD1107 conducted an interlaboratory comparison in which 22 laboratories from 12 countries analyzed three different types of biochar for 38 physical–chemical parameters (macro- and microelements, heavy metals, polycyclic aromatic hydrocarbons, pH, electrical conductivity, and specific surface area) with their preferential methods. The data were evaluated in detail using professional interlaboratory testing software. Whereas intralaboratory repeatability was generally good or at least acceptable, interlaboratory reproducibility was mostly not (20% < mean reproducibility standard deviation < 460%). This paper contributes to better comparability of biochar data published already and provides recommendations to improve and harmonize specific methods for biochar analysis in the future.
Kunststoffe sind wichtige Werkstoffe und heutzutage aus Haushalt und Wirtschaft nicht mehr wegzudenken. Seit Anfang der 1970er-Jahre wird das Vorkommen von Kunststoffpartikeln in Küstengewässern beschrieben. Inzwischen ist Mikroplastik nicht nur im marinen Bereich, sondern auch in weiteren Umweltkompartimenten, Biota und technischen Einrichtungen der Wasserwirtschaft nachgewiesen worden, in dieser Arbeit wird ein Überblick über das Vorkommen von Mikroplastik in der aquatischen Umwelt und ersten bekannten Auswirkungen gegeben. Darüber hinaus werden die aktuellen Untersuchungsverfahren von Probenahme, Probenaufbereitung und Analytik betrachtet und offene fragen diskutiert. Zentral erscheint in diesem Zusammenhang die Entwicklung einer harmonisierten medienübergreifenden Untersuchungsmethodik, die eine Auswertung relevanter Stoffströme ermöglicht und auf notwendige Bewertungskonzepte abgestimmt ist.
The Berlin Congress Hall was a gift of the United States of America to Germany for the Berlin World Exhibition in 1957. The elegantly double-curved roof was made from an advanced prestressed concrete construction. The construction followed the design by the American architect Hugh Stubbins with special structural modifications to comply with German construction rules. No early indications for failure initiation were detected before a sudden partial collapse. On May 21st, 1980, the Southern external roof overhang collapsed. In December 1980, Jörg Schlaich and his co-authors published a summarizing expert opinion about structural causes of failure. The present paper mainly introduces results of cause analysis made at the Federal Institute for Materials Research and Testing (BAM), mandated by the Public Prosecutor at the Berlin District Court to specify the causes of the sudden failure. This paper refers to BAM-publications about analyses that were performed under this mandate and published – most of them in German language – within the first years after failure. The expert's opinions comprise structural considerations materials investigations, metallographic analyses and corrosion. Nowadays experts have learnt from the failure and built a slightly modified roof in the original shape at the 750th birthday of the city of Berlin and re-opened the former Berlin Congress Hall to the public on May 9th, 1987. The Hall is now serving as the House of the Cultures of the World, following the initial intention of the hall.
The objective of this work was to provide updated information on the development of the potential impact of heavy metal containing batteries on municipal waste and battery recycling processes following transposition of the new EU Batteries Directive 2006/66/EC. A representative sample of 146 different types of commercially available dry and button cells as well as lithium-ion accumulators for mobile phones were analysed for their mercury (Hg)-, cadmium (Cd)- and lead (Pb)-contents. The methods used for preparing the cells and analysing the heavy metals Hg, Cd, and Pb were either developed during a former study or newly developed. Several batteries contained higher mass fractions of mercury or cadmium than the EU limits. Only half of the batteries with mercury and/or lead fractions above the marking thresholds were labelled. Alkaline–manganese mono-cells and Li-ion accumulators, on average, contained the lowest heavy metal concentrations, while zinc–carbon batteries, on average, contained the highest levels.
The concentration of contaminants in groundwater samples can be decreased by degradation in the time course between field sampling and quantification in the laboratory, especially in samples from sites where degradation activity is enhanced by remediation measures. The sampling sites covered a variety of priority organic pollutants such as volatile aromatic and chlorinated compounds, phenols and petroleum hydrocarbons and different remediation strategies such as anaerobic and aerobic microbial in situ degradation, in situ chemical oxidation, and on-site purification with biological treatment. The stability of the contaminants' concentration was investigated over a time range of several hours without cooling in the autosampler of the analytical equipment (short term) and over several days of storage until analysis (long term). A number of stabilisation techniques suggested in international standards ISO 5667-3:2013 and ASTM D6517:2000 were compared both with regard to short term and long term stabilisation of the contaminants and their practicability for field sampling campaigns. Long term storage turned out to be problematic for most compound groups even under cooling. Short term stability was problematic also for volatiles such as benzenic aromates, naphthalene and volatile organic halogenated compounds to be analysed by headspace gas chromatography. Acidification (pH <2) was sufficient to prevent degradation of benzenic aromates, naphthalene, phenols and petrol hydrocarbons for up to seven days. The use of acids was not applicable to stabilise volatiles in waters rich in carbonates and sulphides due to stripping of the volatiles with the liberated gases. The addition of sodium azide was successfully used for stabilisation of volatile organic halogenated compounds.
The requirement for a metrological infrastructure to ensure the interchangability of 'nonconventional’ energy gases within existing European infrastructure1 was the driving force behind the work undertaken in the three-year EMRP Characterisation of energy gases project EMRP ENG01 (June 2010 - May 2013).
As part of work package one of the project, Standards and methods were used to perform composition and impurity measurements on samples of real energy gases collected from around Europe. The aim of this study was to compare the results obtained from different labs, and thereby provide an evaluation of the labs’ capabilities and provide insight into the feasibility of different analytical methodologies for use with future measurements.
The great variety of manuscripts found in the Turfan oasis at the Start of the twentieth Century by Grünwedel and Le Coq reflects the cultural backgrounds of, and communication among, the people who travelled along the network of Eurasian trade routes. Specifically, this Connection is directly reflected by the use and distribution of inks, pigments, and papers. Research is now underway to examine these and a report on the initial findings is given below.
The emphasis of the present work was to investigate the photochemical conversion of trans- to cis-zearalenone in edible oils under real-life conditions. For quantitation purposes a cis-zearalenone standard was synthesized and characterized for its identity and purity (≥95%) by 1H NMR, X-ray crystallography, HPLC fluorescence and mass spectrometric detection. In a sample survey of 12 edible oils (9 corn oils, 3 hempseed oils) from local supermarkets all corn oils contained trans-zearalenone (median 194 µg/kg), but no cis-zearalenone was detected. For alteration studies trans-zearalenone contaminated corn oils were exposed to sunlight over 4 and 30 weeks, revealing an obvious shift toward cis-zearalenone up to a cis/trans ratio of 9:1 by storage in colorless glass bottles. Irradiation experiments of trans-zearalenone in different organic solvents confirmed the preferred formation of cis-zearalenone possibly caused by entropic effects rather than by enthalpic entities as investigated by quantum chemical and classical force field simulations.
Der Beitrag thematisiert das Kontaktproblem und damit den kritischen Punkt der historischen gusseisernen und stählernen Lagertechnik. Nach einem Rückblick auf die historische Entwicklung der Bemessung der Lagerwalzen und allgemeinen Ausführungen zur Kontaktproblematik wird anhand analytischer und numerischer Untersuchungen der Zusammenhang zwischen der Kontaktspannung nach Hertz und der Mises-Vergleichsspannung als Grundlage für ein realistisches Bewertungskonzept aufgezeigt.
On the world scale, the European Union has established the most comprehensive regulations for mycotoxins in food and feed. These regulations, which areinter alia expressed in the form of maximum levels, largely affect cereal traders. To ensure the safety of their products and compliance with EU legislation traders are required to quantify the mycotoxin levels in their lots. However, while the analytical approaches of research and enforcement are well known and frequently reviewed in the scientific and legal literature, little detailed information is available on the mycotoxin management concepts of trade. The present article is intended to close this gap. On the basis of the results of two surveys conducted amongst European cereal traders in the years 2007 and 2009, three key issues in commercial mycotoxin management are outlined and discussed in the context of the current scientific literature. These are: the issue of sampling, the availability and performance of suitable analytical methods as well as issues evolving from variations between regulatory and contractual maximum levels.
Zur Toxizität von Brandgasen insbesondere von organischen Stoffen liegen bisher noch unzureichende Erkenntnisse vor, obwohl diese für die Sicherheit der damit konfrontierten Personen oft von entscheidender Bedeutung sind. Ziel der hier dargestellten Untersuchungen ist es, die Zusammensetzung des Brandgases und die Menge der Brandgaskomponenten im Brandfall zu beurteilen und zu quantifizieren sowie entsprechende Prozeduren hierfür aufzuzeigen. Dazu wurden verschiedene Brandszenarien, die durch Verwendung von unterschiedlichen Arten von Prüföfen simuliert wurden, sowie Proben in den unterschiedlichen Größenmaßstäben untersucht. Durch den Einsatz eines mobilen FTIR-Gerätes (Fourier Transformations Infrarot Spektroskopie) ist es experimentell möglich, zeitaufgelöst quantitative Bestimmungen einzelner toxischer Brandgaskomponenten während der jeweiligen Brandszenarien zu ermitteln und somit eine Abschätzung der Toxizität vorzunehmen. Am Beispiel von Polyvinylchlorid (PVC) wird gezeigt, welche Auswirkungen die unterschiedlichen Brandszenarien auf die qualitative und quantitative Brandgaszusammensetzung haben.
Catalyst characterization
(2009)
The objective of this work was to test the compliance of commercially available batteries with the German Battery Ordinance, a project of the German government that was initiated by the Federal Environment Agency. Different types of commercially available dry cells were analysed for their cadmium, lead and mercury contents. The dry cells underwent mechanical pre-treatment, separation of the different components and microwave-assisted digestion before determination of the heavy metals. Mercury is sometimes added to prevent the generation of gaseous hydrogen from the electrochemical process. Lead could be present since it is sometimes used as an alloying element of zinc. Cadmium has no technical importance and is an undesirable impurity. None of the batteries contained higher heavy metal mass fractions than the permissible limits.
A major international inter-comparison exercise on strain-controlled thermo-mechanical fatigue (TMF) has been undertaken to validate a new European Code of Practice for TMF Testing and to provide underpinning information for an ISO Standard. This paper focuses on (a) distribution of samples of Nimonic 90, (b) the establishment of a protocol for testing and reporting results, and (c) the analysis of the results. Participants in the inter-comparison exercise comprised eight inner-circle partners who primarily used test pieces which were all manufactured at the same workshop, albeit of three different test piece geometries, and ten outer-circle participants who manufactured their own test pieces, of their own in-house geometry. Each participant undertook three repeat in-phase (IP) tests and three repeat out-of-phase (OP) tests. The tests were conducted at temperatures cycling between 400 °C and 850 °C, with a strain range selected to give a failure life of approximately 1000 cycles, resulting in a stress range of up to ~1000 MPa. The testing conditions were chosen following a preliminary evaluation of critical testing parameters. Results from solid circular and solid flat test piece geometries, together with hollow tubular test pieces have been compared. The influence of temperature measurement using different types of temperature sensors has also been investigated. In-house repeatability has been assessed, together with inter-laboratory reproducibility. The results have been correlated with modulus and thermal expansion data for individual tests. Initially, the largest contribution to scatter in the results was attributed to human errors in reporting the results, compounded by computer assisted cut-and-paste errors. Once these obvious discrepancies had been corrected, it was possible to use the data sets to point to some recommendations regarding testing procedures that can be incorporated into the Code of Testing Practice [Hähner P et al. Code of practice for thermo-mechanical fatigue testing TMF-Standard-Work Package 6 Report, September 2005] and provide technical underpinning for the ISO Standard. The results and the procedures used for analysis are presented.
A procedure for the quantification of the PCB marker congeners 28, 52, 101, 138, 153, 180 in plastic waste form the recycling of cables in the range of content between 0.1 mg kg-1 and 20 mg kg-1 was validated. Representative reference materials for laboratory analyses were produced using granulates from different recycling processes. The method development included aspects of grinding, sieving, homogenising as well as the comparison of extraction methods and chromatographic conditions. The validated procedure foresees grinding of the technical sample to an upper particle size limit of 0.50 mm followed by extraction with an unpolar solvent such as n-hexane and gas chromatographic determination. LOD and LOQ for individual congeners ranged between 0.01 mg kg-1 and 0.08 mg kg-1. Electron capture detection (ECD) and mass selective detection (MS) were equivalent if chromatographic conditions were appropriately selected. The application of MS was advantageous in presence of significant amounts of interfering components which have been found in some cables.
Three reference materials containing the marker congeners in the range of 0.1 mg kg-15 mg kg-1 were submitted to a final validation intercomparison with 23 selected field laboratories using the developed method. Relative reproducibility standard deviations varied between 15% and 33%.
Large-volume instrumental photon and neutron activation analysis (IPAA resp. INAA) was used for
investigation of shredded electronic waste material. Sample masses from 1 to 150 grams were analysed
to obtain an estimate of the minimum sample size to be taken to achieve a representativeness
of the results which is satisfactory for a defined investigation task. Furthermore, the influence of
irradiation and measurement parameters upon the quality of the analytical results were studied. Finally,
the analytical data obtained from IPAA and instrumental neutron activation analysis (INAA),
both carried out in a large-volume mode, were compared. Values within the limits of satisfactory
agreement were found only partially. Analytical process control using on-site X-ray fluorescence
analysis performed during recycling of electronic waste is currently under development.
Determination of pentachlorphenol (PCP) in waste wood - method comparison by a collaborative trial
(2002)
Two independently developed and validated procedures for the determination of pentachlorophenol (PCP) in waste wood were compared by means of a collaborative trial. Both methods foresee quantification of PCP by gas chromatography (GC-ECD) after acetylation and differ with regard to the use of methanol or toluene/sulphuric acid, respectively, as solvent in the sonication extraction step. Test samples with established analyte homogeneity were prepared from a ground real life starting material. A total of 23 participating laboratories with experience in wood preservative analysis were instructed to apply both methods to three levels of content in the range of 0.520 mg PCP/kg. In case of the toluene/sulphuric acid extraction, lower recoveries and higher interlaboratory dispersion of results at the higher PCP contents were observed. Seen against the background of the Horwitz equation a reproducibility standard deviation of not, vert, similar19% for the methanol extraction at the 4.5 mg/kg level meets the requirement for a sound analytical method. Thus, the sonication extraction procedure with methanol has been annexed as a reference method to the German waste wood regulation.