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Mineralische Baustoffe werden aus Baurestmassen, industriellen Rückständen und Verbrennungsrückständen zurückgewonnen. Die Bundesanstalt für Materialforschung und -prüfung (BAM) und ihr Fachbereich Schadstofftransfer und Umwelttechnologien haben mit verschiedenen Partnern den Feinkornbereich fokussiert.
ISO 10156:2010 contains a test method and a calculation method for flammability of gases and gas mixtures for the selection of cylinder valve outlets. The calculation method is used also to classify gas mixtures according to the national and international dangerous goods and dangerous substances regulations, e.g. according to the UN Recommendations on the Transport of Dangerous Goods (UN TDG) and the Globally Harmonized System of Classification and Labelling of Chemicals (UN GHS). The calculation method for gas mixtures requires substance parameters of the single components. These are the coefficients for the fire potential (Tci) and for inerting ability, the so-called nitrogen equivalence (Kk), which have been estimated conservatively by means of flammability data.
BAM checked Tci and Kk values of ISO 10156:1996 using three-component diagrams (Flammable gas-Inert-Air) of the CHEMSAFE® database. The experimental fundamentals and the principles of the calculation method are summarized in this paper. The revised data for Tci and Kk values were adopted in the tables of ISO 10156:2010.
Furthermore, subcategorization of flammable gases has been proposed by a UN working group and shall be implemented in the GHS in the meantime. The subcategorization requires the lower flammability limit (LFL) as an additional indicator. Therefore, a test method and a calculation method for LFL were proposed by BAM and have been implemented in the new draft of ISO/CD 10156:2016.
The calculation method for gas mixtures is based on Le Chatelier’s rule and was extended by using the Kk values for inert components in the mixture. The calculated LFLs of methane-inert gas mixtures were compared with experimental values for different types of inert gases. It could be shown that calculated LFLs are in good agreement with experimental values if the Kk values derived from three-component flammability diagrams are used. Although using the Kk values of ISO 10156:2010 leads to higher deviations, the results are still on the safe side.
Why Africa can spearhead innovative and sustainable cement and concrete technologies globally
(2016)
The perception of concrete in the society as well as in the politics is rather negative. This becomes obvious in the fact that the phrase “concrete jungle” has become synonym for hapless living with no perspectives. In politics and research funding, it is also not easy to create a broader audience, since concrete is falsely considered as old-fashioned material that is sufficiently understood today and does not need further considerations, particularly compared to allegedly newer materials. However, particularly since the last two decades the technology has completely changed. Binders of today are no more the same binders as used before, and concrete mixture compositions of today diverge quite significantly from compositions in the past. There is little understanding world-wide about that. This causes that potentials the concrete technology bears are wasted.
In the broadly found opinion that concrete is old-fashioned and ugly, it is ignored that architectural sins are not inherent to the material, which actually is extremely versatile and CO2-friendly compared to all other construction materials available. It is also ignored that 98% of the outer Earth’s crust are made of the elements cement and concrete are made from, and therefore it will be an illusion to believe that the complementary 2% can create materials to develop regions and infrastructures in less developed areas in the world.
For betterment in Africa the infrastructural development should have highest priority, since poor connections between settlements are responsible for enormous Price increases [2], and urban traffic congestion is responsible for an incredible loss of productivity. It is not unrealistic to assume that earners that are dependent on a car get stuck in traffic about 3-4 hours per day in cities like Lagos, Nairobi or Dar es Salaam. However, the traffic congestions do not only affect the car owners negatively but the living of the entire urban population every day.
Besides infrastructure, housing should be the other priority, since a large part of the African population does not live in adequate condition. This is a societal problem, since unequal Distribution of wealth is a major driving force for instability in societies. The latter has a global impact, since 8 many phenomena that can be observed all over the world such as political radicalism, xenophobia, terrorism, and migration can often be linked to instable societies.
However, the importance of infrastructure has an even wider range. Most African countries go through a change process recently. In order to strengthen very positive perspectives, the focus in politics and research funding is put on issues such as agriculture, energy, and health, which are without doubt extremely important issues. However, it is typically overlooked that all enhancements in these areas can only become effective, when an infrastructure is created to support the implementation of better concepts. Mobility is the key to a prosperous future, and mobility can only be granted by infrastructural construction activities. Hence, compared to many other regions in the world, cement and concrete technologies have a significantly higher relevance in Africa.
Die Weiterentwicklung der Verfahren und Techniken zur dauerhaften Überwachung von Bauwerken ist Gegenstand zahlreicher Forschungs- und Entwicklungsvorhaben. Der praktische Einsatz dieser Verfahren beschränkt sich bisher jedoch auf durchaus zahlreiche, jedes für sich jedoch sehr konkrete Einzelprobleme beschreibende Projekte. Einer flächendeckenden Anwendung stehen häufig – berechtigte oder unberechtigte – Bedenken zur Effizienz dieser Verfahren im Vergleich zu baupraktisch etablierten Verfahren wie z. B. regelmäßigen Bauwerksinspektionen entgegen. Weiterführende Aspekte wie optimierte Wartungskonzepte oder Lebensdauerprognosen zur begründeten Priorisierung von Ertüchtigungsmaßnahmen sind aufgrund des Fehlens zeitnah realisierbarer, monetärer Vorteile oftmals schwer vermittelbar. Dieser Beitrag soll einige grundlegende Ziele aktueller Monitoringkonzepte anhand von Projektbeispielen der BAM aufzeigen, um die Potentiale dieser Verfahren zu verdeutlichen und mögliche sinnvolle Anwendungsgebiete zu erschließen. Im Vordergrund dieses Übersichtsbeitrages stehen dabei die grundlegenden Ideen und Ziele dieser Projekte; bezüglich der Ergebnisse wird auf die entsprechenden Fachveröffentlichungen verwiesen.
Präsentation der Ergebnisse eines Ringversuchs zur Kompetenzbewertung von Prüflaboratorien auf dem Gebiet der anorganischen und organischen Bodenanalytik: Polyzyklische aromatische Kohlenwasserstoffe (PAK) in Boden, Mineralölkohlenwasserstoffe (MKW) in Boden, Elemente in Sediment und Gesamtcyanid in Boden.
Pharmacologically active compounds are omnipresent in contemporary daily life, in our food and in our environment. The fast and easy quantification of those substances is becoming a subject of global importance. The fluorescence polarization immunoassay (FPIA) is a homogeneous mix-and-read format and a suitable tool for this purpose that offers a high sample throughput. Yet, the applicability to complex matrices can be limited by possible interaction of matrix compounds with antibodies or tracer.
Caffeine is one of the most frequently consumed pharmacologically active compounds and is present in a large variety of consumer products, including beverages and cosmetics. Adverse health effects of high caffeine concentrations especially for pregnant women are under discussion. Therefore, and due to legal regulations, caffeine should be monitored. Automated FPIA measurements enabled the precise and accurate quantification of caffeine in beverages and cosmetics within 2 min. Samples could be highly diluted before analysis due to high assay sensitivity in the low μg/L range. Therefore, no matrix effects were observed.
The antiepileptic drug carbamazepine (CBZ) is discussed as a marker for the elimination efficiency of wastewater treatment plants and the dispersion of their respective effluents in surface water. The development of a FPIA for CBZ included the synthesis and evaluation of different tracers. Using the optimum tracer CBZ-triglycine-5-(aminoacetamido) fluorescein, CBZ concentrations in surface waters could be measured on different platforms: one sample within 4 min in tubes or 24 samples within 20 min on microtiter plates (MTPs). For this study, a commercially available antibody was used, which led to overestimations with recovery rates up to 140% due to high cross-reactivities towards CBZ metabolites and other pharmaceuticals.
For more accurate CBZ determination, a new monoclonal antibody was produced. In this attempt, methods for improving the monitoring during the production process were successfully applied, including feces screening and cell culture supernatant screening with FPIA. The new monoclonal antibody is highly specific for CBZ and showed mostly negligible cross-reactivities towards environmentally relevant compounds. Measurements at non-equilibrium state improved the sensitivity and selectivity of the developed FPIA due to slow binding kinetics of the new antibody. Additionally, this measure enables for CBZ determination over a measurement range of almost three orders of magnitude. The comprehensively characterized antibody was successfully applied for the development of sensitive homogeneous and heterogeneous immunoassays.
The new antibody made the development of an on-site measurement system for the determination of CBZ in wastewater possible. After comprehensive optimization, this automated FPIA platform allows the precise quantification of CBZ in wastewater samples only pre-treated by filtration within 16 min. Recovery rates of 61 to 104% were observed. Measurements in the low μg/L range are possible without the application of tedious sample preparation techniques.
Different FPIA platforms including MTPs, cuvettes and tubes were successfully applied. For the choice of the right format, the application field should be considered, e.g. desired sample throughput, usage for optimization or characterization of antibodies or if a set-up for routine measurements is sought for. For high sample throughput and optimization, FPIA performance on MTPs is advantageous. The best results for the application to real samples were obtained using kinetic FP measurements in cuvettes.
Lead (Pb) isotope amount ratios are commonly used in applications ranging from archaeology and forensic sciences to terrestrial and extra-terrestrial geochemistry. Despite their utility and frequency of use, only three certified isotope amount ratio reference materials are currently available for Pb: NIST SRMs 981, 982 and 983. Because SRM 981 has a natural Pb isotopic composition, it is mainly used for correcting instrumental mass discrimination or fractionation. This means that, at present, there are no other certified isotope reference materials with natural Pb isotopic composition that could be used for validating or verifying an analytical procedure involving the measurement of Pb isotope amount ratios.
To fill this gap, two new reference materials, both certified for their Pb isotopic composition, have been produced together with a complete uncertainty assessment. These new reference materials offer SI traceability and an independent means of validating or verifying analytical procedures used to produce Pb isotope amount ratio measurements.
ERM-EB400 is a bronze material containing a nominal Pb mass fraction of 45 mg/kg. ERM-AE142 is a high purity solution of Pb with a nominal mass fraction of 100 mg/kg. Both materials have been specifically produced to assist analysts in verifying or validating their analytical procedures. Note that while one of these reference materials requires the chemical separation of Pb from its matrix (ERM-EB400), the other does not (ERM-AE142). Details on the certification of these isotope reference materials are provided in this report.
For the classification, safe handling and use of the chemicals, special standardized testing procedures have been developed and are used worldwide. Safety experts must be able to fully rely on the precise execution of the respective laboratory tests and assessments. In this context, interlaboratory tests are a crucial element of a laboratory's quality system. Participation in interlaboratory tests is explicitly recommended by the standard ISO/IEC 17025.
The present document reports the results of the interlaboratory test 2015-2016, which was performed on the test method DIN EN 15188:2007 “Determination of the spontaneous ignition behaviour of dust accumulations”. It was organized by BAM in the frame of the co-operation project CEQAT-DGHS Centre for Quality Assurance for Testing of Dangerous Goods and Hazardous Substances.
The test method DIN EN 15188:2007 is applied to characterize the self-ignition behaviour of combustible dusts. The experimental basis for describing the self-ignition behaviour of a given dust is the determination of the self-ignition temperatures (TSI) of differently-sized volumes of the dust sample by isoperibolic hot storage experiments (storage at constant oven temperatures) in commercially available ovens. The results measured this way reflect the dependence of the self-ignition temperatures on the volume of a dust accumulation.
The interlaboratory test 2015-2016 on the method DIN EN 15188:2007 is the latest in a systematic stepwise built up series of method validation interlaboratory tests and internal laboratory investigations. The aim of this interlaboratory test was to determine measurement uncertainties of the modified method DIN EN 15188 for different substances, covering a sufficiently wide range of self-ignition behaviours in the scope of the DIN EN 15188 of the four basket test to extrapolate to storage volumes up to 1000 m³ and the single basket test for a basket volume of 1000 cm³.
The precision of the four basket test and the single basket of the modified method DIN EN 15188 can be assessed as acceptable for the four sample materials investigated in the current interlaboratory test 2015-2016. It was possible to derive a functional equation for the measurement uncertainty U depending on the storage volume V. The measurement uncertainty cannot be ignored and must be considered, if TSI results should be used in practice.