Sanitär- und Kommunaltechnik; Umwelttechnik
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- 2022 (185) (entfernen)
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- Biocides (14)
- Korrosion (11)
- Antimicrobial resistance (10)
- Immunoassay (9)
- Mikroplastik (7)
- PFAS (7)
- Atmosphärische Korrosion (6)
- Corrosion (6)
- Klärschlamm (6)
- Risk assessment (6)
Organisationseinheit der BAM
- 4 Material und Umwelt (92)
- 1 Analytische Chemie; Referenzmaterialien (35)
- 4.1 Biologische Materialschädigung und Referenzorganismen (29)
- 7 Bauwerkssicherheit (26)
- 4.3 Schadstofftransfer und Umwelttechnologien (25)
- 1.8 Umweltanalytik (20)
- 6 Materialchemie (18)
- 7.6 Korrosion und Korrosionsschutz (17)
- 4.4 Thermochemische Reststoffbehandlung und Wertstoffrückgewinnung (16)
- 6.6 Physik und chemische Analytik der Polymere (14)
Eingeladener Vortrag
- nein (109)
It is of high priority to capture the extent of microplastics (MP) contamination for understanding its impact and consequences to our environment. However, due to a lack of standardized methods, MP analysis as well as its quality assurance, is still a challenge. The thermal extraction desorption-gas chromatography/-mass spectrometry (TED-GC/MS) as a novel innovative thermoanalytic method can detect MP particles in environmental samples based on their decomposition products. According to MP analysis, a distinctively larger polyethylene (PE) content in comparison to other synthetic polymers was detected in environmental samples. Various substances within the matrix which have a similar molecular structure to PE, like fats and oils, might interfere with its marker and lead to an overestimation. In this investigation an automated extraction method, the accelerated solvent extraction (ASE), is introduced as quality control tool before TED-GC/MS measurement. Thereby, not the extract like usually used, but the solid filtrate is analyzed. The aim is to clean the environmental samples from solvent removable compounds which could lead to false positive signals and thus receive a more accurate PE mass. Consequently, a sample mimicking environmental samples with a defined matrix and a known polymer mass was generated. The common polymers polyethylene, polypropylene, polystyrene and styrene-butadiene rubber, used as an indication for tire wear, were added to the matrix. Different parameters for ASE extraction were varied such as different solvents, filters and purge time. Finally, a PE recovery rate of 91 % after extraction could be reached.
Glyphosate (GPS) is the most widely used pesticide in the world whose use increased dramatically after the introduction of genetically modified crops engineered to resist its herbicidal action during application. In recent years, there have been growing concerns over its toxicity following its classification by the International Agency for Research on Cancer (IARC) as a probable carcinogen as well as reports of its ecotoxicological effects. This resulted in increased efforts to develop quick and sensitive detection methods.
In this work, molecular imprinting was combined with direct fluorescence detection of GPS by improving its solubility in organic solvents using tetrabutylammonium (TBA+) and tetrahexylammonium (THA+) as counterions. To achieve fluorescence detection, a fluorescent crosslinker containing urea binding motifs was used as a probe for GPS-TBA and GPS-THA salts in chloroform, generating stable complexes through hydrogen bond formation. The GPS/fluorescent dye complexes were imprinted into 2–3 nm molecularly imprinted polymer (MIP) shells on the surface of sub-micron silica particles. Thus, the MIP binding behavior could be easily evaluated by fluorescence titrations in suspension to monitor the spectral changes upon addition of the GPS analytes. While MIPs prepared with GPS-TBA and GPS-THA both displayed satisfactory imprinting following titration with the corresponding analytes in chloroform, GPS-THA MIPs displayed better selectivity against competing molecules. Moreover, the THA+ counterion was found to be a more powerful phase transfer agent than TBA+, enabling the direct fluorescence detection and quantification of GPS in water in a biphasic assay. A limit of detection of 1.45 µM and a linear range of 5–55 µM, which matches well with WHO guidelines for the acceptable daily intake of GPS in water (5.32 µM), have been obtained. The assay can be further optimized to allow miniaturization into microfluidic devices and shows potential for on-field applications by untrained personnel.
The ubiquitous presence of unintended plastics in the environment has been an issue in scientific studies and public debate. Recent studies on MP findings are focused mainly on aquatic systems, while little is known about MP in terrestrial ecosystems. Fermentation residues, sewage sludge and compost are secondary raw material fertilizers and represent a possible input path of plastics in soils. Soils are final sinks for micro plastics. In this context, samples were taken in a combined fermentation and composting plant in Germany to get real compost samples which were investigated. Existing regulations include requirements for total contents of plastics in combination with visual determination methods. In order to avoid possible underdeterminations, precise detection methods should be used in the future from a scientific point of view. For this reason, the use of thermoanalytical detection is an appropriate way. Spectroscopic methods such as Raman or FTIR are not suitable for determining the mass content of microplastic, as these output a particle number. In Germany, compost is a potential vector for MP in soil due to its use as fertilizer. Therefore, we show the application of TThermoExtractionDesorption-GasChromatography-MassSpectrometry (TED-GC-MS) as a fast, integral analytical technique, which in contrast to the spectroscopic methods does not measure the number of particles but a mass content. In a nitrogen atmosphere the sample is pyrolyzed to 600 °C and an excerpt of the pyrolysis gases is collected on a solid phase adsorber. Afterwards, the decomposition gases are desorbed and measured in a GC-MS system. Characteristic pyrolysis products of each polymer can be used to identify the polymer type and determine the mass contents in the present sample. For the first time the work represents a routine procedure for the determination of plastics in composts and fermentation residues. This current study will also give inside in various important aspects of sample preparation, which include a meaningful size fractionation, a necessary density separation regarding the removal of inorganic contents and at finally a homogenization.
Per- und polyfluorierte Alkylsubstanzen (PFAS) im Klärschlamm - Analytische Methoden und Grenzwerte
(2022)
Per- und Polyfluoralkylsubstanzen (PFAS) sind eine Gruppe von mehr als 4700 anionischen und kationischen anthrophonen Stoffen, die aufgrund ihrer inerten chemischen Stabilität und ihrer Widerstandsfähigkeit gegen den Abbau durch Hitze oder Säuren in einer Vielzahl von Produkten verwendet werden. Infolge der ständigen Verwendung, vor allem in Feuerlöschschäumen für die Luftfahrt, wurden in Tausenden von Industrie- und Militäranlagen kontaminierte Böden und Grundwasservorkommen gefunden. Aufgrund der ständigen Verwendung von fluorierten Konsumgütern haben sich jedoch auch Abwässer und Klärschlamm aus Kläranlagen als Quelle für die Kontamination der aquatischen Umwelt mit PFAS erwiesen. Infolge der strengeren Vorschriften und Beschränkungen, die in den letzten Jahren für die Verwendung langkettiger (≥C8) PFAS erlassen wurden, findet in der chemischen Industrie eine deutliche Verlagerung hin zur Herstellung kurz- (C4-C7) und ultrakurzkettiger (C1-C3) Alternativen statt. Mit der Novellierung der Klärschlammverordnung im Jahr 2017 hat der deutsche Gesetzgeber die Ausbringung von Klärschlamm auf landwirtschaftlichen Flächen verboten, und bis 2029/2032 wird die Ausbringung von Klärschlamm in der Landwirtschaft vollständig verboten sein. Während die Belastung der Umwelt mit organischen Schadstoffen wie PFAS, Pestiziden und Arzneimitteln nicht mehr erwünscht ist, muss Phosphor (P) aus Klärschlamm weiterhin zur Herstellung hochwertiger P-Dünger für eine Kreislaufwirtschaft genutzt werden. Derzeit können pflanzenverfügbare P-Düngemittel aus Klärschlamm/Abwasser mit verschiedenen Behandlungsmethoden hergestellt werden, darunter Fällung, Auslaugung und thermische Behandlung. Der Verbleib von PFAS bei der Auslaugung, Ausfällung und Behandlung von Klärschlamm und Abwasser ist jedoch noch weitgehend unbekannt.
Detektion von Mikroplastik
(2022)
Per- and polyfluoroalkyl substances (PFAS) are a group of more than 4700 anionic and cationic anthrophonic substances which have been used extensively in a variety of products and industries due to their inert chemical stability and resistance to degradation by heat or acids. As a result of continuous use, mainly in aviation firefighting foams, thousands of industrial and military installations have been found to contain contaminated soil and groundwater resources. However, because of the continuous use of fluorinated consumer products, also effluents and sewage sludge from wastewater treatment plants (WWTPs) have been shown to be an important source of PFAS contamination into the aquatic environment. Resulting from recent stricter regulations and restrictions in the last years on the use of long chain (≥C8) PFAS, there is a significant shift in the chemical industry towards production of short (C4-C7) and ultrashort (C1-C3) chain alternatives. With the amendment of the Sewage Sludge Ordinance in 2017 the German legislation banned sewage sludge application on agricultural land, and by 2029/2032 sewage sludge will be completely prohibited from agricultural application. While environmental exposure of organic pollutants like PFAS, pesticides and pharmaceuticals are no longer desirable, phosphorus (P) from sewage sludge must still be used to produce high-quality P-fertilizers for a circular economy. Currently, plant-available P-fertilizers from sewage sludge/wastewater can be produced using a variety of treatment approaches including precipitation, leaching, and thermal treatment. However, the fate of legacy and emerging PFAS compounds during P leaching, precipitation and treatment from sewage sludge and wastewater is for the most parts still unknown.
Calcium sulfate minerals are abundant in natural and engineered environments and they exist in the form of three hydrates: gypsum (CaSO4·2H2O), bassanite (CaSO4·0.5H2O), and anhydrite (CaSO4). Due to their relevance in natural and industrial processes, the formation pathways of these calcium sulfate phases from aqueous solution have been the subject of intensive research1.
The state-of-the-art of the calcium sulfate formation mechanisms builds upon and goes beyond what we have come to appreciate in the astounding intricacy of other mineral formation processes from ions in aqueous solutions. The original, and rather naive, 'textbook' image of these phenomena, stemming from the adaptation of classical nucleation and growth theories, has increased in complexity due to the discovery of a variety of precursor and intermediate species2. These include solute clusters (e.g. prenucleation clusters, PNCs), liquid(-like) phases, as well as amorphous and nanocrystalline solids etc.. In this context, a number of studies have already revealed that nucleation in the CaSO4-H2O system is non-classical, where the formation of the different crystalline phases involves several steps including a common amorphous precursor1, 3, 4.
In this contribution we show that the formation of the amorphous phase involves the aggregation of small primary particles into larger disordered aggregates exhibiting a "brick-in-the-wall" structure5, 6. The actual crystallization occurs by the restructuring and coalescence of the particles ("bricks") into a given calcium sulfate phase depending on the physicochemical conditions of the solution. Importantly, the rearrangement process does not continue until a (nearly-)perfect homogeneous single crystal is obtained. Instead it comes to a stop, or at least significantly slows down. Such a process thus yields a final imperfect mesocrystal, composed of smaller domains rather than a continuous crystal structure, within which the domains are separated by an amorphous (i.e. less ordered) calcium sulfate phase.
Hence, the non-classical crystallization process of CaSO4 yields a final imperfect mesocrystal with an overall morphology resembling that of a single crystal, yet composed of smaller nano-domains. Importantly, these observations reveal that organic-free calcium sulfate mesocrystals grown by a particle mediated-pathway preserve in the final crystal structure a “memory” or “imprint” of their non-classical nucleation process, something that has been overlooked until now. Furthermore, the nano-scale misalignment of the structural sub-units within these crystals can propagate through the length-scales, and be expressed macroscopically as misaligned zones/domains in large single crystals. Indeed, by considering large anhydrite crystals from the famous Naica Mine (“Cueva de los cristales”) we observed a suite of correlated self-similar void defects spanning multiple length-scales7. These flaws, in the macroscopic crystal, stem from “seeds of imperfection” originating from a particle-mediated nucleation pathway. Hence, building a crystal could be viewed as Nature stacking blocks in a game of Tetris, whilst slowly forgetting the games core concept and failing to fill rows completely.
BIOCIDE
(2022)
Deciphering microbiological influenced corrosion processes on steel with single cell-ICP-ToF-MS
(2022)
Microbiologically influenced corrosion (MIC) is a highly unpredictable process dictated by the environment, microorganisms, and the respective electron source. Interaction pathways between cells and the metal surface remain unclear. The development of this novel single cell-inductively coupled plasma-time of flight-mass spectrometry analytical method and a MIC-specific staining procedure facilitate the investigation of steel-MIC interactions. With this it is possible to analyze the multi-elemental fingerprint of individual cells. The detection method revealed elemental selectivity for the corrosive methanogenic archaeal strain Methanobacterium-affiliated IM1. The interface between material and environmental analysis thus receives special attention, e.g., when considering MIC on solid steel. Hence, the possible uptake of individual elements from different steel samples is investigated. Results showed the cells responded at a single-cell level to the different types of supplemented elements and displayed the abilities to interact with chromium, vanadium, titanium, cobalt, and molybdenum from solid metal surfaces. The information obtained will be used in the future to elucidate underlying mechanisms and develop possible material protection concepts, thus combining modern methods of analytical sciences with materials research.
Antimicrobial resistance (AMR) is a global health problem with the environment being an important compartment for the evolution, selection and transmission of AMR. These processes are impacted by pollution with antibiotics. However, biocides used as disinfectants and material preservatives are major pollutants by far excceding the market for antibiotics in terms of mass. Our work shows that biocides have the potential to affect evolutionary processes towards AMR by increasing the rates of de-novo mutation and conjugation. These effects depend on the species and biocidal substance. Importantly, chlorhexidine and quaternary ammonium compounds (QACs) affect rates of mutation and conjugation at environmentally relevant concentrations in E. coli. Moreover, our results show a connection between the RpoS-mediated general stress and the RecA-linked SOS response with increased rates of mutation and conjugation, but not for all biocides. Furthermore, our work highlights the potential of biocides to contribute to selection and transmission of AMR. We show that the application of biocides, especially QAC disinfectants, leads to the rapid evolution of tolerance (i.e. increased survival) in adaptive laboratory evolution (ALE) experiments. The evolved tolerant strains have a selective advantage in the presence of environmentally-relevant concentrations of antibiotics, which could lead to the stabilization of biocide tolerance in environments where biocides and antibiotics co-occur (e.g. wastewater, animal stables). ALE experiments with biocide tolerant strains indicate a decreased evolvability of resistance to antibiotics. Taken together, our work shows the importance of assessing the contribution of biocides on evolution, selection and transmission of AMR in the environment.
Bisphenol A (BPA) is widely used in many Polymers. Many outdoor applications are made from BPA-based materials which are exposed to a variety of environmental impacts, like temperature, solar radiation, rain, and others. This could lead to damaging and aging of the material which might cause leaching or migration of pollutants into the environment. To understand the fate and behavior different transformation products of selected Bisphenols will be generated and analyzed.
Der Fachbeirat kommt bereits seit 13 Jahren in seiner jetzigen Form zusammen, um Zulassungsrichtlinien, weitere Dokumente und fachliche Fragestellungen zu beraten. Die Zeit bringt auch personelle Veränderungen mit sich, darüber wollen wir berichten. Derzeit wird die Zulassungsrichtlinie für Schutzschichten im Fachbeirat und in seiner Arbeitsgruppe Geotextilien und Kunststoff Dränelemente (AG Geotextilien) überarbeitet. Zudem wurde die Zulassungsrichtlinie für Kunststoffdichtungsbahnen auf den aktuellen Stand der Regelsetzung und Normung gebracht. Bestimmte Medien, die hier bei einigen Prüfungen verwendet werden, dürfen nicht mehr in der EU in Verkehr gebracht werden. Hier werden die Hintergründe und Zusammenhänge in Kürze aufgezeigt. Zuletzt wird die Diskussion in Bezug auf den Einsatz von Rezyklaten in den zugelassenen Produkten aufgeführt.
Der Fachbeirat kommt bereits seit 13 Jahren in seiner jetzigen Form zusammen, um Zulassungsrichtlinien, weitere Dokumente und fachliche Fragestellungen zu beraten. Die Zeit bringt auch personelle Veränderungen mit sich, darüber wollen wir berichten. Derzeit wird die Zulassungsrichtlinie für Schutzschichten im Fachbeirat und in seiner Arbeitsgruppe Geotextilien und Kunststoff Dränelemente (AG Geotextilien) überarbeitet. Zudem wurde die Zulassungsrichtlinie für Kunststoffdichtungsbahnen auf den aktuellen Stand der Regelsetzung und Normung gebracht. Bestimmte Medien, die hier bei einigen Prüfungen verwendet werden, dürfen nicht mehr in der EU in Verkehr gebracht werden. Hier werden die Hintergründe und Zusammenhänge in Kürze aufgezeigt. Zuletzt wird die Diskussion in Bezug auf den Einsatz von Rezyklaten in den zugelassenen Produkten aufgeführt.
Bisphenol A (BPA) is widely used in Polycarbonate (PC), Polyacrylic resins (PAR), Polysulfones (PSU), Epoxy resins (ER), and Polyetherimides (PEI). It is also used in recycled Polyvinyl chloride (PVC) [1–3]. These BPA-containing materials have a wide area of application, especially outside. All outdoor applications are exposed to a variety of environmental impacts, like temperature, solar radiation (physical influences), chemical influences (rain or ozone), biological influences (microorganisms), and mechanical influences (hail, sand). These impacts are damaging and aging the material which can be followed by leaching or migration of pollutants like Bisphenol A into the environment. Understanding the fate and behavior of the released pollutants is very important. Therefore, different transformation products of selected Bisphenols will be generated and analyzed.
Fluorescent semiconductor nanocrystals, also known as quantum dots (QDs), enabled many advancements in biotechnology, photovoltaics, photocatalysis, quantum computing and display devices. The high versatility of this nanomaterial is based on their unique size-tunable photoluminescence properties, which can be adjusted from the visible to the near-infrared range. In contrast to other nanomaterials, QDs made the transition from a laboratory curiosity to the utilization in commercial products, like the QLED television screen or in smartphone displays. The best investigated QDs are composed of heavy metals like cadmium or lead, which is not the best choice in terms of toxicity and environmental pollution. A more promising material is Indium Phosphide (InP), which is also currently used by Samsung, Sony and co. in the QLED displays.
In this contribution, I would like to give you a sneak peek behind the curtains of nanomaterial synthesis and show how this material is produced, how to stabilize their structural properties, and assess their toxicity in environmentally relevant conditions. Furthermore, I would like to present a synthesis method to accomplish the last open challenge in display technology of a blue luminescent LED based on QDs by introducing a new element to the InP QDs.
Deutschland befindet sich inmitten eines umfassenden Transformationsprozesses hin zu einer klimaneutralen und nachhaltigen Wirtschaft und Gesellschaft. Sowohl das Erreichen der Klimaziele als auch die Anpassung an die Folgen des Klimawandels fordern ein rasches, bestimmtes und gleichzeitiges Handeln in vielen Sektoren und Lebensbereichen.
Normen und Standards können einen wichtigen Beitrag zum Erreichen dieser Ziele leisten. So haben Normungsorganisationen weltweit mit der ISO London Declarationeinen Pakt zur Unterstützung des Klimas geschlossen. Das bestehende Normenwerk muss auf Klimawandel-Tauglichkeit überprüft und eine Überarbeitung angestoßen werden.
Der Klimawandel als Querschnittsthema betrifft alle Wirtschaftszweige, und daher bieten DIN, DKE und VDI mit dieser durch Impulsvorträge eingeleiteten Diskussionsreihe eine Plattform zum Austausch über Normung als Werkzeug zum Thema Klima mit allen Akteuren.
Around 2.5 million tons of municipal sewage sludge (dry matter) are produced in Ger-many every year. The disposal or recycling of this mass often confronts plant operators with considerable problems. In addition to organic substances, sewage sludges also contain important inorganic nutrients that can be recycled. Due to the finite nature of phosphorus as a resource and in favor of natural material cycles, it makes sense to utilize the phosphorus bound in sewage sludge. Therefore, Phosphorus recycling from sewage sludge will be obligatory in Germany from 2029. However, the pollutants pre-sent in sewage sludge, such as heavy metals and organic trace pollutants, are prob-lematic. In many cases, the sewage sludge is incinerated, removing organic compo-nents, and leaving a mineral residue. Various processes exist for the reprocessing of sewage sludge ashes. Reliable analytics and process monitoring are required for all of them.
In this context, the first and most important task of BAM regarding new materials or processes is safety in technology and chemistry through validated and correct analyt-ics. Since there are no reference materials for sewage sludge ashes so far, it is not possible to make any statements about the extent to which the measured values of the comparative measuring methods are correct at all. Therefore, suitable, and representa-tive reference materials are indispensable for the validation of the measurement results and the quality assurance during the entire recycling process. Great care is required to select and prepare these reference materials. The reference materials must corre-spond in matrix to the samples that are to be investigated in the industrial process. An iron-rich and an aluminum-rich sewage sludge ash from mono-incineration plants were selected for this purpose. 10 kg of each sewage sludge ash were homogenized, char-acterized, and prepared. The main, minor and trace element compositions of the sew-age sludge ashes are determined by different measuring methods. The candidate ref-erence materials will be available as BAM-U200 und BAM-U201.
Per- and polyfluoroalkyl substances (PFAS) are a group of anionic, cationic and zwitterionic synthetic products, in which the hydrogen atoms on the carbon skeleton of at least one carbon atom have been completely replaced by fluorine atoms and which include more than 4730 compounds, depending on the definition. As a result of continuous and prolific use, mainly in aviation firefighting foams, thousands of industrial and military installations have been found to contain contaminated soil, groundwater and surface water. As a result of the perpetual use of PFAS containing products, effluents and sewage sludge from wastewater treatment plants (WWTPs) have been observed to be an important pathway for PFAS into the environment. In Germany, phosphorus and other nutrients from sewage sludge and wastewater should be recycled in WWTPs of cities with a large population. However, it is not clear if PFAS contamination from wastewater and sewage sludge end up in novel wastewater-based fertilizers. Normally, PFAS are analyzed using PFAS protocols typically with liquid chromatography tandem mass spectrometry (LC-MS/MS) quantification. To get a better overview of the amount of “total PFAS,” we applied sum parameter methods based on combustion ion chromatography (CIC) to screen the PFAS contaminations in various sewage sludge and wastewater-based fertilizers. Furthermore, current decontamination strategies of PFAS-burdened soils mainly consist of adsorption methods using adsorbents for fixation of PFAS in the ground. A second option is the utilization of a “pump and treat” process, cycling polluted soils through a washing plant leading to the concentration of the pollutants in the fine fraction. Only a subsequent, high-energy consuming pyrolysis process guarantees the total destruction of all fluorinated organic contaminants. Both approaches are cost-intensive and not intended for the direct decomposition of all PFAS contaminants. Hence, there is a great demand for innovative developments and chemical treatment technologies, dealing with new strategies of tackling the PFAS problem.
„Getränkekühler optimal einsetzen“: So sparen Sie die Energiekosten und schonen das Klima.
Wussten Sie, dass Sie durch den Einsatz eines effizienten Getränkekühlers (Energieeffizienzklasse B) ca. 114 € pro Jahr sparen im Vergleich zu einem weniger effizienten Gerät (Energieeffizienzklasse D)? Aber nicht immer gibt es die Möglichkeit ein Neugerät anzuschaffen. Oft werden die Kühlgeräte von Getränkeherstellern zur Präsentation ihrer Waren zur Verfügung gestellt. Trotzdem tragen am Ende die Betreiber:innen die Betriebskosten der Geräte.
Aber auch beim Einsatz Ihres weniger effizienten Getränkekühler gibt es verschiedene Möglichkeiten, die Energiekosten zu senken. Beispielsweise kann schon der Einsatz einer Zeitschaltuhr zu einer Stromreduzierung von bis zu 50 Prozent oder auch die richtige Platzierung der Geräte an kühlen Orten ohne Zugluft zu einem geringeren Strombedarf von bis zu 30% führen.
In unserer Checkliste für die Aufstellung und das Betreiben von Getränkekühlgeräten zeigen wir Ihnen einfache Schritte, um den Energieverbrauch schnell zu senken.
Problem: Lack of knowledge about TCE stocks and flows in urban mines. TCE analysis is hindered by extreme heterogeneity of the waste and a lack of suitable CRMs. Analytical procedures providing SI traceable results are not available.
Solution: To enable comparability of analytical results and thus finally allow the improved recycling procedures, sampling strategies, analytical procedures, enabling SI traceable values and CRMs for TCE to be developed.
The screening of coatings shows that the modification by adding individual pigment was not sufficient to protect carbon steel even during a short-term exposure, indicated by the discoloration after only seven days of exposure.
Electrochemical tests indicated that the coating cathodically protects carbon steel or slows down the corrosion reaction.
A long-term exposure test confirmed that the PANI/SiO2 modified coating successfully protects the carbon steel in the Sibayak artificial geothermal water at 150 °C for 6 months.
Basic oxygen furnace slag (BOFS) is a by-product of steelmaking of which about 10.4 Mt are produced annually in the EU. BOFS is mostly used in road construction, earthwork and hydraulic engineering. However, in this use, the iron bound in BOFS is lost and the opportunity to produce higher value products from BOFS is forgone.
In recent decades, many researchers have investigated a thermochemical process to reduce iron oxides to metallic iron in molten BOFS. The metallic iron formed separates from the reduced slag due to its higher density and can be recovered. An advantage of this process is that simultaneously the chemical composition of the reduced slag is adapted to that of the Portland cement clinker and the hydraulic reactive mineral alite is formed.
In this study, BOFS was reduced in a small-scale electric arc furnace using petrol coke as reducing agent, and the hydraulic properties of the reduced, low-iron BOFS were investigated. Despite a chemical and mineralogical composition similar to that of Portland cement clinker, the reduced BOFS produced less heat of hydration, and its reaction was delayed compared to Portland cement. However, the addition of gypsum, as is also done in cement production from Portland cement clinker, has been found to accelerate the hydration rate of reduced BOFS.
Further research to improve the hydraulic properties of the reduced slag is essential. If successful, the production of a hydraulic binder and crude iron from BOFS could have economic and ecological benefits for both the cement and steel industry.
The talk is about microplastics in soil. Some results were presented with mainly state of the art according to microplastics in standardization.
Aschen und Schlacken und aus der Abfallverbrennung, chemische und mineralogische Zusammensetzung
(2022)
Aschen und Schlacken sind mengenmäßig der wichtigste Reststoffstrom in der thermischen Abfallbehandlung. Die enthaltenen elementaren Metalle werden mit gängigen Verfahren abgetrennt und einer Verwertung als Sekundärrohstoff zugeführt. Durch die chemische und mineralogische Zusammensetzung der mineralischen Fraktion wird das Umweltverhalten sowie die abfallrechtliche Einstufung bestimmt. Methoden zur Ermittlung der Einstufung werden vorgestellt. Das Löslichkeitsverhalten von Schwermetallen in gealterten Aschen hängt meist vom pH-Wert in den standardisierten Auslaugtests ab. Das davon abweichende Verhalten von Antimon wird detailliert beschrieben.
The addition of WC and TiC in a nickel bonded NbC cermet was investigated regarding the tribological behavior under dry oscillating sliding at different relative humidities φ and the cutting performance in dry cylindrical turning of C45E at different cutting speeds. NbC-12Ni-12WC-14TiC shows similar coefficient of friction f and wear rate compared to NbC-12Ni at φ = 2 %, but no pronounced decrease in f with increasing humidity. When turning C45E, NbC-12Ni-12WC-14TiC shows lower material removal VW compared to other NbC-based cermets, which can be attributed to inhomogeneities in the cutting material and a low hardness.
Micro-(nano-)encapsulation technology involves building of a barrier between the core and the environment and offers a number of benefits to preserve the functional and physicochemical properties of core material. Tremendous progress has been made in synthesizing well-defined capsules to achieve desired properties such as particle size, chemical composition, and controlled release of the payload.
Encapsulation of volatile organic compounds (VOCs) that could evaporate with a defined rate is of immense interest for application in emission reference materials (ERM). These are urgently needed for quality assurance and quality control purposes (QA/QC) required by test standards for the determination of chemical emissions of construction and other materials for interior use. As such ERMs are hardly available on the market, the EU-funded EMPIR project MetrIAQ [1] was started to fill this gap by developing a material with temporally constant emission of VOCs typically found in indoor air.
Different capsules in a size range between 5 and 50 μm were synthesized through an interfacial polyaddition/polycondensation reaction in direct (water-in-oil) system. As VOC several types of hydrophobic liquid materials were used. After synthesis, the morphology and physicochemical properties of capsules were characterized by electron microscopy, FTIR and DSC/TGA. An encapsulation efficiency up to 90% could be reached. The emission kinetic of volatile agents was studied in emission test chambers at 23 °C and 50% RH for 14 days. First results indicate that variation of the cross-linking grade of the shell material is one important parameter to adjust the desired emission rate. The overall aim is to achieve a consistent emission profile that decreases by less than 10 % over a target period of at least 14 days.
Contamination of the environment with antibiotics is of great concern as it promotes the evolution of antimicrobial resistances. In case of amoxicillin (AMX) in the aquatic environment, further risk arises from hydrolysis products (HPs) which can cause allergy. To assess these risks, a comprehensive investigation and understanding of the degradation of AMX is necessary. We investigated the hydrolysis rate of AMX in different types of water as well as the influence of temperature and irradiation. The content of the heavy metal ions copper and zinc was found to be crucial for the hydrolysis rate of AMX and stability of HPs. Eventually, a new degradation pathway for AMX could be elaborated and confirmed by tandem mass spectrometry (LC-MS/MS).
The exposure to antimicrobial substances drives the evolution of antimicrobial resistance (AMR). Biocides are antimicrobials used as disinfectants, antiseptics and preservatives. They find application on a large scale in the industrial and medical sector, but also in private households. In terms of mass, the worldwide use of biocides exceeds that of antibiotics. Thus, despite their important role in preventing the spread of pathogens, due to their ubiquity, biocides are suspected to be drivers of the antimicrobial resistance crisis. In our work we try to understand how biocides contribute to the emergence of AMR, what the underlying adaptation principles and mechanisms are and how they compare to those found for antibiotics.
Here, I present results which demonstrate that phenotypic heterogeneity in E. coli, namely the formation of tolerant persister cells, can enable the survival of disinfection and consequentially facilitate the evolution of AMR. Using experimental evolution that selects for tolerance, we find that mutations in lipid A biosynthesis arise following periodic treatment with benzalkonium chloride (BAC), a widely used disinfectant. BAC tolerance is associated with additional, diverse mutations as well as changes in the susceptibility to antibiotics from different classes and changes in motility and biofilm formation, suggesting extensive regulatory re-wiring in the evolved clones. Remarkably, we find that fitness costs (growth rate reduction) incurred by BAC tolerance are alleviated in the presence of antibiotics. These findings demonstrate the complexity underlying the adaptation to antimicrobials and highlight the links between persistence to disinfectants and resistance evolution to antimicrobials.
During iron and steel production, several by-products such as slags, dusts, and sludges are generated in addition to pig iron and steel as primary products. Especially for filter dusts and sludges containing zinc and lead from gas purification, there are still considerable recycling problems. However, the high heavy metal contents make landfilling of these dusts and sludges cost-intensive and ecologically problematic. In addition, the relatively high zinc and iron loads represent a valuable resource, which can make reprocessing of the material with recovery of the zinc and iron loads as secondary raw materials ecologically as well as economically attractive. Nevertheless, established recycling methods like the Waelz process fall short in regaining more than one valuable metal from the dusts and operate only under narrow ranges of material compositions, which makes it problematic to adapt these processes to new dust compositions as are to be formed in future steel work operations.
To tackle these problems, the German Federal Institute for Materials Research and Testing (BAM) and Ferro Duo GmbH investigate innovative recycling methods for steelwork dusts and sludges in a joint project. This mainly focusses on regaining valuable metals such as iron as well as zinc from blast furnace sludge (BFS) and electric arc furnace dust (EAFD) by thermochemical treatment.
Therefore, mixtures of these materials are heated under inert atmosphere employing the carbon present in BFS as internal reducing agent. During the process, metallic iron is formed in the solid reaction product while zinc and other volatile heavy metals are evaporated. This paves the way for the generation of zinc as well as sponge iron as two separate products valuable for metallurgical processes. The process basically consists of heating a mixture of BFS and EAFD to temperatures between 700 and 1100 °C under inert (e.g., nitrogen) or reducing (e.g., CO) gas flow. When a suitable mixing ratio is applied, the carbon present in the BFS can be effectively used as reducing agent for iron and zinc present in both starting materials generating a solid residue with high metallic iron and low carbon content as well as a gas stream laden with zinc and other volatile heavy metals, that can be regained by off-gas treatment.
The project aims at testing this concept as a continuous process in a pilot plant established by Ferro Duo GmbH with BAM supplying comprehensive scientific support by lab- and small scale-experiments.
Additionally, considering the necessity to mitigate CO2 emissions and the resulting shift in compositions of steel work dusts and sludges, our research also investigates replacement of carbon present in the sludges by hydrogen as potentially carbon-neutral reducing agent. Here, the use of non-explosive forming gas as reducing agent for EAFD shows potential to give a product high in metallic iron while zinc and other heavy metals are effectively evaporated from the solid material making it possible to regain them from the exhaust gas stream.
Occupational health is an important topic, especially in industry, where workers are exposed to airborne by-products (e.g., dust particles and gases). Therefore, continuous monitoring of the air quality in industrial environments is crucial to meet safety standards. For practical and economic reasons, high-quality, costly measurements are currently only carried out sparsely, both in time and space, i.e., measurement data are collected in single day campaigns at selected locations only.
The project “Robot-assisted Environmental Monitoring for Air Quality Assessment in Industrial Scenarios” (RASEM) addresses this issue by bringing together the benefits of both – low- and high-cost – measuring technologies enabling costefficient long-term air quality monitoring in realtime: A stationary network of low-cost sensors that is augmented by mobile units carrying high-quality sensors. By mapping the distribution of gases and particles in industrial environments with the proposed RASEM system, measures can be identified to improve on-site working conditions much faster than using traditional methods.
In this paper, we detail the technical aspects of RASEM and introduce the mobile platforms used.
Occupational health is an important topic, especially in industry, where workers are exposed to airborne by-products (e.g., dust particles and gases). Therefore, continuous monitoring of the air quality in industrial environments is crucial to meet safety standards. For practical and economic reasons, high-quality, costly measurements are currently only carried out sparsely, both in time and space, i.e., measurement data are collected in single day campaigns at selected locations only.
The project “Robot-assisted Environmental Monitoring for Air Quality Assessment in Industrial Scenarios” (RASEM) addresses this issue by bringing together the benefits of both – low- and high-cost – measuring technologies enabling cost-efficient long-term air quality monitoring in realtime: A stationary network of low-cost sensors that is augmented by mobile units carrying high-quality sensors. By mapping the distribution of gases and particles in industrial environments with the proposed RASEM system, measures can be identified to improve on-site working conditions much faster than using traditional methods.
In this presentation, we detail the technical aspects of RASEM and introduce the mobile platforms used.
Soil acts as a final sink for pollutants. Microplastics from different sources such as plastic mulching, littering, compost, sewage sludge, sedimentary deposition, and tyre abrasion are expected to be found in soil. However, representative and comprehensive information is missing on the sources, transport, and fate. Therefore, a reliable analysis method for microplastics in soils needs to be developed.
The presented work describes the development of a procedure for microplastics analysis in soils. A representative sampling based on the on-site conditions and a sample preparation method was established and comprised of a drying step, the separation of microplastic particles > 1 mm, and a density separation for particles < 1 mm. The detection of the large microplastic particles (> 1 mm) was conducted with Attenuated Total Reflection - Fourier Transform infrared Spectroscopy (ATR-FTIR) , while Thermal Extraction Desorption - Gas Chromatography / Mass Spectrometry (TED-GC/MS) was applied for particles < 1 mm, gaining information on the type of polymer and mass fraction. Based on the established method, 14 environmental soil samples ? with different exposure of microplastics from agriculture, industrial sites, roads, and floods were investigated.
Due to the arbitrary microplastic particle distribution among the samples for large microplastics, it was reasoned that the found particles were unrepresentative. In contrast, microplastic particles < 1 mm were discovered in a high mass in soil samples exposed to plastic mulching or fertilization with sewage sludge or compost (0 – 115 mg/kg). On average, microplastic contents detected in soil samples taken from a construction site and an inner-city lake were higher (13 – 238 mg/kg). As expected, microplastic content in soil sampled in proximity to roads was more pronounced in the upper soil layers. In contrast, very remote sampling sites, expectably uncontaminated, did not lead to the detection of microplastic regarding to thermoanalytical detection method.
In a proof of concept experiment several in vivo and in vitro ecotoxicological tests were applied to evaluate the effect of microplastics (tyre abrasion, polystyrene containing hexabromocyclododecane) in natural soils. In summary, while no effects of the examined probes could be detected on higher levels of biological organization after exposures to earthworm E. andrei, significant changes in several oxidative stress related biomarkers were observed.
Microplastics are widely distributed in aquatic and terrestrial environments, up to now less is known on toxicological impacts under realistic conditions. Research so far has focused mainly on the impacts on organisms by fresh plastic fragments or beats. However, plastic materials found in the environment are mainly a mixture of different polymers and additives and particularly degraded during aging processes. Although especially oxidized degradation products might escape from plastic materials during aging, there is a lack of information on potentially adverse effects on aquatic biota. The latter is of particular interest as oxidized chemicals become more water soluble due to higher polarity and are more bio-available, therefore.
The present study focused on plastic leachates of polystyrene (PS) and polylactic acid (PLA), which were derived from alternating stress by hydrolysis and UV radiation. Test specimen of PS, PLA or PS/PLA blends (each 50 %) were alternatingly maintained in water at 45 °C for five days and UV radiated at 45 °C for two days, for in total six weeks. Ecotoxicological effects of potentially generated degradation products of plastic materials in the storage water (mineral water, pH: 7.2) were detected by algae growth inhibition tests with Desmodesmus suspicatus and photosystem II inhibition tests with Raphidocelis subcapitata.
Results clearly indicate inhibitory effects on algae growth by contaminants in the storage water of stressed plastic materials with increasing growth inhibition of proceeding hydrolysis and UV stress times. Here, different plastics cause variable responses of algal growth. First chemical analyses indicate dissolved monomers and their oxidation products of plastic materials as possible driver of detected ecotoxicological effects, since detected microplastic particles do not seem to harm algae.
The existing data highlight the relevance of plastic aging as a framework for microplastic ecotoxicity evaluation and allow a proof of concept.
extraWERT Forschungsvorhaben
(2022)
Die novellierte AbfKlärV (2017) beinhaltet die Verpflichtung zum P-Recycling ab einem P-Gehalt im Klärschlamm von 20 g/kg. Im Vortrag werden Ergebnisse des Forschungsvorhabens extraWERT zu diesem Themenkomplex vorgestellt. Es werden Untersuchungen zu P-Gehalten deutscher Klärschlämme und zu den zulässigen Analysemethoden dafür vorgestellt.
Overview of the state of the art and current trends with the main topics:
- renewable sources in flame retardant polymers (flame retarded bio-polymers and biocomposites; bio-flame retardants, renewable adjuvants from industrial waste)
- flame retardancy meets sustainability
- concepts between analogy and out-of-the-box.
Der Vortrag wurde im Rahmen der konstituierenden Sitzung des Arbeitskreises "Atmosphärische Korrosion" der GfKORR - Gesellschaft für Korrosionsschutz e.V. gehalten. Er stellt die zur Diskussion stehenden Fragestellungen und Herausforderungen im Bereich der atmosphärischen Korrosion zusammen, denen sich der neue Arbeitskreis widmen wird.
Per- and polyfluoroalkyl substances (PFAS) are anionic, cationic and zwitterionic synthetic products, in which the hydrogen atoms on the carbon skeleton of at least one carbon atom have been completely replaced by fluorine atoms (see Figure 1) and which include more than 4730 compounds, depending on the definition. As a result of continuous and prolific use, mainly in aviation firefighting foams, thousands of industrial and military installations have been found to contain contaminated soil, groundwater and surface water. Furthermore, because of the continuous contamination through PFAS containing commercial products, effluents and sewage sludge from WWTPs have been shown to be an important source of PFAS discharge into the aquatic environment. In the last few years, legacy PFAS (≥C4) have been found in various environments, including soil, water and wastewater, and their environmental pathways have been partly described. To get a better
overview of the amount of “total PFAS,” sum parameter methods like total oxidizable precursor (TOP) assay and methods based on combustion ion chromatography (CIC) are in development. CIC results in data regarding the sum of absorbable organic fluorine (AOF) or extractable
organic fluorine (EOF), which can also quantify other organically bound fluorine compounds such as fluorinated pesticides and pharmaceutical. Additionally, for research purpose several spectroscopical methods like X-ray photoelectron spectroscopy (XPS), fluorine K-edge X-ray absorption near-edge structure (XANES) spectroscopy, particular induced gamma-ray emission (PIGE) spectroscopy and 19F nuclear magnetic resonance (NMR) spectroscopy are available. Therefore, an overview is given on various analytical techniques for PFAS in environmental samples and their application possibilities discussed for different kind of PFAS compounds
Per- and polyfluoroalkyl substances (PFAS) are a large group of anionic, cationic, or zwitterionic organofluorine surfactants used in the formulations of thousands of products and consumer goods, including aqueous film-forming foams (AFFF) used to suppress aviation fires in training scenarios, non-stick cookware, fast-food wrappers, water-repellent fabrics, medical equipment. Because PFAS have been extensively used in a variety of AFFF products they can be found in soils from industrial and military installations. Current decontamination strategies of PFAS-burdened soils mainly consist of adsorption methods using adsorbents for fixation of PFAS in the ground. A second option is the utilization of a “pump and treat” process, cycling polluted soils through a washing plant leading to the concentration of the pollutants in the fine fraction. Only a subsequent, high-energy consuming pyrolysis process guarantees the total destruction of all fluorinated organic contaminants. Both approaches are cost-intensive and not intended for the direct decomposition of all PFAS contaminants. Hence, there is a great demand for innovative developments and chemical treatment technologies, dealing with new strategies of tackling the PFAS problem. Previously, mechanochemical treatment of polychlorinated organic compounds in soils showed an efficient dechlorination. Thus, we investigated mechanochemical treatment of PFAS contaminated soils with various additives in a ball mill and analyzed the PFAS defluorination with gas chromatography mass spectrometry (GCMS) and liquid chromatography tandem mass spectrometry (LC-MS/MS), respectively, as well es the fluoride mineralization by ion chromatography (IC) and fluorine K-edge X-ray absorption near-edge structure (XANES) spectroscopy.
Analytical Challenges for PFAS in Environmental Samples - Methods, Approaches and Applicability
(2022)
Per- and polyfluoroalkyl substances (PFAS) are anionic, cationic and zwitterionic synthetic products, in which the hydrogen atoms on the carbon skeleton of at least one carbon atom have been completely replaced by fluorine atoms and which include up to 1.7 M compounds, depending on the definition. As a result of continuous and prolific use, mainly in aviation firefighting foams, thousands of industrial and military installations have been found to contain contaminated soil, groundwater and surface water. Furthermore, because of the continuous contamination through PFAS containing commercial products, effluents and sewage sludge from WWTPs have been shown to be an important source of PFAS discharge into the aquatic environment. In the last few years, legacy PFAS (≥C4) have been found in various environments, including soil, water and wastewater, and their environmental pathways have been partly described.
Several long-chain PFAS species, and their respective salts are considered as persistent organic pollutants by the United Nations Stockholm Convention. These pollutants have been linked to altered immune and thyroid function, liver disease, lipid and insulin dysregulation, kidney disease, adverse reproductive and developmental outcomes, and cancer. A significant shift in the chemical industry towards production of short (C4-C7) and ultrashort (C1-C3) alternatives was observed in response to recently intensified regulations and restrictions on the use of long-chain (≥C8) PFAS. PFAS analysis in environmental samples is currently mainly done by liquid chromatography tandem mass spectrometry (LC-MS/MS). This efficient method is conducted in a targeted fashion analyzing a small subset of PFAS. The US EPA method for analysis of PFAS using LC-MS/MS for example currently lists 40 PFAS (≥C4). However, to get a better overview of the amount of “total PFAS,” sum parameter methods like total oxidizable precursor (TOP) assay and methods based on combustion ion chromatography (CIC) are in development. CIC results in data regarding the sum of absorbable organic fluorine (AOF) or extractable organic fluorine (EOF), which can also quantify other organically bound fluorine compounds such as fluorinated pesticides and pharmaceutical. Moreover, non-target and suspect screening mass spectrometry can be used to identify novel emerging PFAS and partly unknown fluorinated compounds in environmental samples. Furthermore, to analyze ultrashort PFAS (C1-C3), supercritical fluid chromatography (SFC), hydrophilic interaction chromatography (HILIC) and gas chromatography-mass spectrometry (GC-MS) are available, but further research is needed to develop reliable and accurate methods to quantify several ultrashort PFAS in environmental samples.
Additionally, for research purpose several spectroscopical methods like X-ray photoelectron spectroscopy (XPS), fluorine K-edge X-ray absorption near-edge structure (XANES)spectroscopy, particular induced gamma-ray emission (PIGE) spectroscopy and 19F nuclear magnetic resonance (NMR) spectroscopy are available.
The exposure to antimicrobial substances drives the evolution of antimicrobial resistance (AMR). Biocides are antimicrobials used as disinfectants, antiseptics and preservatives. They find application on a large scale in the industrial and medical sector, but also in private households. In terms of mass, the worldwide use of biocides exceeds that of antibiotics. Thus, despite their important role in preventing the spread of pathogens, due to their ubiquity, biocides are suspected to be drivers of the antimicrobial resistance crisis. In our work we try to understand how biocides contribute to the emergence of AMR, what the underlying adaptation principles and mechanisms are and how they compare to those found for antibiotics.
Here, I present results which demonstrate that phenotypic heterogeneity in E. coli, namely the formation of tolerant persister cells, can enable the survival of disinfection and consequentially facilitate the evolution of AMR. Using experimental evolution that selects for tolerance, we find that mutations in lipid A biosynthesis arise following periodic treatment with benzalkonium chloride (BAC), a widely used disinfectant. BAC tolerance is associated with additional, diverse mutations as well as changes in the susceptibility to antibiotics from different classes and changes in motility and biofilm formation, suggesting extensive regulatory re-wiring in the evolved clones. Remarkably, we find that fitness costs (growth rate reduction) incurred by BAC tolerance are alleviated in the presence of antibiotics. These findings demonstrate the complexity underlying the adaptation to antimicrobials and highlight the links between persistence to disinfectants and resistance evolution to antimicrobials.
Data for the publication "The role of extracellular polymeric substances of fungal biofilms in mineral attachment and weathering" (https://doi.org/10.1038/s41529-022-00253-1). It includes:
- The Summary of the EPS concentration, EPS sugar components and EPS linkages.
- The Summary of the XPS analysis of freeze-dried biofilm samples of all strains.
- The Summary of the pH, Mg, SI and Fe concentration, biomass and olivine dissolution rate for each time point of all dissolution experiments.
Advances in high-resolution imaging of cell cultures and tissues exposed to airborne particles
(2022)
High-resolution microscopy techniques are fundamental to our ability to investigate and quantify the toxicological effects of airborne particulate pollutants via imaging of in vitro respiratory models exposed to well-characterised particle suspensions and aerosols. However, all imaging methods are limited in their spatio-temporal resolution, information capacity and suitability for minimally invasive time lapse imaging. Many traditional methods are incompatible with the more complex three-dimensional model systems which have potential for greater correlation between in vitro studies and real-world health effects. New techniques can overcome these limits, increasing our ability to understand and measure biological responses to particulate exposure at subcellular, cellular and multicellular scales. We have investigated a variety of microscopy methods for imaging different respiratory models.
Microcolonial black fungi are inhabitants of exposed natural and man-made surfaces in all climate zones. Genetic studies are hampered by slow growth, lacking sexual cycles and difficulties to transform these fungi. Recently, we implemented CRISPR/Cas9-based genetic tools enabling efficient targeted mutations of the rock inhabitant Knufia petricola (Eurotiomycetes/Chaetothyriales) for studying stress responses, the unusual types of cell division, mineral weathering and symbiotic interactions with phototrophic microbes (Voigt, Knabe et al. 2020, Sci Rep; Erdmann et al. 2022, Front Fungal Biol). To further explore the genome of this fungus as representative of the polyphyletic group of black fungi and to assign functions to yet unknown genes, a forward genetics approach is aimed. We chose the two-component Activator/ Dissociation (Ac/Ds) transposon system from maize for generating a collection of insertional mutants by in-vivo mutagenesis. For the optimal use of this genetic tool, an inducible promoter for the expression of the Ac transposase and by this the regulatable transposition of the resistance cassette-containing Ds transposon is requested. However, endogenous promoters for nitrate assimilation and galactose catabolism that are often used in fungi for regulatable gene expression are not inducible by their substrates in K. petricola suggesting that the regulatory networks for nutrient acquisition differ significantly in the oligotrophic black fungi. Therefore, the metabolism-independent Tet-on system was adopted and validated using a Ptet::gfp construct. No GFP fluorescence was detected in absence of the inducer doxycycline (DOX) while fluorescence intensities increased with increasing inducer concentrations. Consequently, the Tet-on system is suitable for regulatable expression of endogenous and foreign genes in K. petricola.
Mitogen-activated protein (MAP) kinases are highly conserved in animals, plants, and fungi and represent fundamental parts of signaling networks in eukaryotic cells. Black DHN (1,8-dihydroxynaphthalene) melanin and orange carotenoids are produced by many fungi in specific cell types/under certain conditions for protecting cells from abiotic and/or biotic stresses. Microcolonial black fungi constitutively produce DHN melanin, contain the conserved carotenogenic gene cluster, exhibit slow yeast-like growth and survive in extreme environments. Thus, the question arises to which extent pigment formation and responses mediated by the stress-activated MAP kinase module contribute to the observed extremotolerance. We address this question in the rock inhabitant Knufia petricola, the only representative of the extremotolerant black fungi that is genetically amendable. Here, the mutations of pks1, phs1 and both genes result in melanin-free (pink), carotenoid-free (black) and pigment-free (white) strains, respectively (Voigt Knabe et al. 2020, Sci Rep). The gene encoding the stress-activated MAP kinase was deleted in the wild-type and different pigment-deficient backgrounds. In addition, strains were generated that express a GFP-SAK1 fusion protein from the sak1 locus to follow the cytosolic/nuclear shuttling of SAK1 upon stress. Growth of the obtained single, double and triple deletion mutants was tested by dropping cell suspensions on solid media supplemented with different stress-inducing agents. The Δsak1 mutants show slightly reduced growth rates even under non-stress conditions and are hypersensitive to different stress conditions: reduced growth is observed on media inducing, for instance, osmotic, oxidative, membrane, and pH stress, and upon incubation at 30 °C (heat stress). Melanin-free Δsak1 mutants are more sensitive than black Δsak1 mutants to some but not all stress conditions, suggesting that melanin and the SAK1 pathway have complementary roles in protecting K. petricola from stress.
DHN (1,8-dihydroxynaphthalene) melanin is produced by different Ascomycetes via slightly differing biosynthetic routes. The polyketide synthases (PKS) release the heptaketide YWA1, the hexaketide AT4HN or the pentaketide T4HN. The first two products are deacetylated by ‘yellowish-green’ hydrolases to T4HN, and T4HN is further converted by a core set of enzymes to DHN. Final polymerization steps are accomplished by multicopper oxidases (MCOs). The involved genes are tightly clustered, partially clustered or widely distributed in the genomes of DHN melanin-producing fungi. DHN melanogenesis is often regulated in a spatial and temporal fashion resulting e.g. in melanized reproduction, survival and/or infection structures. In contrast, a polyphyletic group of Ascomycetes (microcolonial fungi/ black yeast) dwelling in hostile habitats such as bare rock surfaces in hot and cold deserts, exhibits constitutive melanogenesis. Here, we report on the identification and functional characterization of the DHN melanogenic genes of Knufia petricola as a representative of the Chaetothyriales, the sister order of the Eurotiales. Orthologs for all melanogenic genes were identified in the genome of K. petricola A95, including one gene encoding the polyketide synthase (KpPKS1), two genes encoding ‘yellowish-green’ hydrolases (KpYGH1,2), two genes encoding THN reductases (KpTHR1,2) and one gene encoding a scytalone dehydratase (KpSDH1). Ten genes encoding MCOs were identified, all MCOs are predicted to be secreted. The genes are not clustered in the genome but are highly expressed. Gene functions are studied by generation of single, double, and multiple deletion mutants in K. petricola and by heterologous expression in Saccharomyces cerevisiae for reconstruction of the synthesis pathway.
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.
The diversity of fused filament fabrication (FFF) filaments continues to grow rapidly as the popularity of FFF-3D desktop printers for the use as home fabrication devices has been greatly increased in the past decade. Potential harmful emissions and associated health risks when operating indoors have induced many emission studies. However, the lack of standardization of measurements impeded an objectifiable comparison of research findings. Therefore, we designed a chamber-based standard method, i.e., the strand printing method (SPM), which provides a standardized printing procedure and quantifies systematically the particle emission released from individual FFF-3D filaments under controlled conditions. Forty-four marketable filament products were tested. The total number of emitted particles (TP) varied by approximately four orders of magnitude (1E9 ≤ TP ≤ 1E13), indicating that origin of polymers, manufacturer-specific additives, and undeclared impurities have a strong influence. Our results suggest that TP characterizes an individual filament product and particle emissions cannot be categorized by the polymer type (e.g., PLA or ABS) alone. The user's choice of a filament product is therefore decisive for the exposure to released particles during operation. Thus, choosing a filament product awarded for low emissions seems to be an easily achievable preemptive measure to prevent health hazards.
To reveal the corrosion resistance of casing steel/mortar interface in CO2 injection condition, sandwich samples were prepared and exposed up to 20 weeks in aquifer fluid under 10 MPa and 60 °C. Cross section analysis revealed the crevice corrosion as main mechanism instead of pitting corrosion, which would be expected to happen in the extremely high Chloride concentration. Detailed analysis using EDS line scan shown the slow diffusion of Chloride, suggesting why pitting did not happen after 20 weeks. To mimic the passivated steel surface, the steel coupon was passivated in simulated pore solution having pH 13.5 for 42 days. The passivated coupon was further exposed to NGB solution for 28 days. Electrochemical characterization was performed along the exposure processes to reveal the change in impedance, indicating the corrosion resistance of steel casing/mortar interface.
Healthy and energy efficient buildings must be free from disturbing odours. Odour emissions from building materials can be measured with the well-known and accepted standard ISO 16000-28 “Indoor air – Part 28: Determination of odour emissions from building products using test chambers”. For commonly used emission test chambers the sample air is collected in containers (bags) and presented to a group of panel members for the purpose of evaluating the odour. A standard sets requirements for the on-demand presentation in detail. These include the validation procedure for container materials, pre-treatment of bags, details on storage of filled bags and how to carry out the measurements. However, although these measures are proven in practice, incorrect measurements are still possible. Also errors can occur due to a very complex measurement procedure. So, there is a great need for research into how the odour samples are presented.
The proposal planned to be presented will introduce a new development in sample provision by using an adapter which enables collection and provision of sample air without storage or transport of bags. The adapter is a sample container which is permanently positioned on the emission test chamber´s outlet and continuously filled with sample air flowing through it. The flow is briefly interrupted at the time when a sample is taken by a panel member for the test.
The size of the container is sufficient to provide enough sample air for evaluation by at least one panel member via a funnel. Since sampling and presentation are technically connected, it means you can almost do away with storage or transportation and thus it can be presented almost unchanged to the panelmembers. The aim is to reduce measurement errors in the odour samples provision process and the improvement of measurement reproducibility. The paper presents the construction of the adapter as well as the results of emission and odour tests carried out so far.
Significant Cu-deposition and ‑precipitation only occurred in combination with carbon steel. High-alloyed materials prevent the disturbing Cu-agglomeration. Pb-deposition and ‑precipitation only occurred in combination with carbon steel. No negative Pb-effect could be observed in combination with high-alloyed steels. High alloyed corrosion resistant alloys are suitable and shall be chosen for future design of the piping system, either in massive or in cladded form, if formation of crevices with non-metallic materials can be excluded!
One criterion to evaluate the odour of a sample is perceived
intensity П which is evaluated with the aid of a comparative scale. The procedure is well accepted but also time consuming and extensive. The study should help simplify the testing procedure by asking the panel members to only indicate whether a sample is perceived as less to equally intense or of greater intensity in comparison to a given acetone concentration of 7 pi on the comparative scale. In Germany a value of 7 pi is required for products to be suitable for the indoor use. The results show that the simplified test is basically suitable.
Biocides, including disinfectants and antimicrobial surfaces (AMCs), are important to prevent the spread of pathogens and antimicrobial resistant bacteria via surfaces. However, concerns have been raised about the evolution and selection of resistance against disinfectants and AMCs. In turn, resistance against disinfectants and AMCs can be associated to antibiotic resistance due to cross-resistance and co-resistance. We need to understand the mechanisms and risks of disinfectants and AMCs for resistance and cross-resistance evolution to optimize their application and safeguard their long-term efficacy. We used adaptive laboratory evolution (ALE) experiments based on repeated exposure of bacteria to disinfectants. Our results show that repeated disinfection of E. coli with benzalkonium chloride in suspension results in a 2000-fold increase in survival within 5 exposure cycles. Adaption is linked to the initial presence of persister cells highly tolerant to benzalkonium chloride. We used the same approach to develop standardizable ALE experiments to determine resistance evolution to AMCs. The results highlight rapid adaptation of E. coli and P. aeruginosa towards copper surfaces. Moreover, there are multiple situations in the clinic or in the environment in which biocides and antibiotics co-occur and in which combination effects can shape their antimicrobial activity or their selective effects. Our work with P. aeruginosa shows prevalent combination effects of biocides and antibiotics, ranging from synergy to antagonism and resulting in the selection for or against antibiotic resistant strains. The combination effects are dependent on the biofilm mode-of-growth, manifesting in apparent differences in the structural arrangement of antibiotic sensitive and resistant strains in biofilms exposed to combinations. Furthermore, biocides affect rates of mutation and horizontal gene transfer, thereby having a potential facilitating effect on resistance evolution. Taken together, our work shows that the role of biocides as potential drivers of resistance evolution and selection deserves further study and regulative action.
A series of field exposure tests according to ISO 9223 up to 9226 was carried out at different locations to determine the corrosivity and the corrosion progress of different test sites throughout northern and eastern Germany. Standard test specimens of steel, zinc, copper and aluminium were exposed to rural, city and marine atmosphere at test sites of the Bundesanstalt für Materialforschung und -prüfung (BAM). Test sites at city atmosphere comprised exposure on a rooftop, next to a highly frequented road and directly at a motorway. Exposure under marine conditions was carried out at Heligoland in the North Sea. The specimens were stored under sheltered and unsheltered conditions on each test site, respectively. Corrosion rates after the first year of field exposure were determined and used for the classification of the atmospheres and the test sites regarding the corrosivity category.
Results after the first year of exposure were presented at the EUROCORR 2018 in Cracow. The current presentation will present an update of results of the systematic study after five years of exposure. The corrosion progress and the mass loss of the standard metals steel, zinc, copper and aluminium will be presented and discussed with respect to the atmospheric conditions and the time of wetness at the test sites. In addition, the difference between sheltered and unsheltered conditions will be discussed.
Flexible, niedrigdichte Schäume aus Biokunststoffen im Extrusionsverfahren herzustellen war bisher industriell noch nicht möglich. Im Verarbeitungstechnikum Biopolymere des Fraunhofer IAP wurde in einem Projekt die Eignung von PBS-basierten Biokunststofftypen für Schaumanwendungen erforscht und weiterentwickelt.
Water treatment with activated carbon (AC) is an established method for the removal of organic micropollutants and natu ral organic matter. However, it is not yet possible to predict the removal of individual pollutants. An appropriate material characterization, matching adsorption processes in water, might be the missing piece in the puzzle. To this end, this study examined 25 diferent commercially available ACs to evaluate their material properties. Frequently reported analyses, including N2 adsorption/desorption, CHNS(O), point of zero charge (PZC) analysis, and X-ray photoelectron spectroscopy, were conducted on a selected subset of powdered ACs. Inorganic elements examined using X-ray fuorescence and X-ray difraction spectroscopy revealed that relative elemental contents were distinctive to the individual AC’s raw material and activation procedure. This study also is the frst to use thermogravimetric analysis (TGA) coupled to Fourier-transform infrared spectroscopy (FTIR) to conduct quantitative analyses of functional surface oxygen groups (SOGs: carboxylic acid, anhydride, lactone, phenol, carbonyl, and pyrone groups) on such a large number of ACs. The comparably economical TGA method was found to provide good surrogates for the PZC by pyrolytic mass loss up to 600 ◦C (ML600), for the oxygen content by ML1000 and for the carbon content by oxidation. Mass loss profles depict the AC’s chemistry like fngerprints. Furthermore, we found that SOG contents determined by TGA-FTIR covered a wide individual range and depended on the raw material and production process of the AC. TGA and TGA-FTIR might therefore be used to identify the suitability of a particular AC for a variety of target substances in diferent target waters. This can help practitioners to control AC use in waterworks or wastewater treatment plants.
Ziel des Projekts HYTEGRA ist die Herstellung leichter Gesteinskörnungen durch hydrothermale Behandlung quarz- und kalkreicher Reststoffe. Als Ausgangsstoffe dienen heterogener Mauerwerkbruch aus Bau- und Abbruchabfällen als SiO2-Träger und Papierasche aus dem Altpapierrecycling als CaO-Träger. Für beide Reststoffe besteht derzeit ein Verwertungsdefizit. Das Verfahren beruht auf der Idee des rohstofflichen Recyclings, d. h. die chemisch-mineralogischen Stoffeigenschaften werden für die hydrothermale Stoffumwandlung genutzt. Bei der Härtung der Hydrothermalgranulate bilden sich Calciumsilicathydrat-Phasen (CSH) aus der Reaktion zwischen Quarzpartikeln und Kalk im Autoklav bei 200 °C und 16 bar Sattdampf.
The introduction of fluorine in organic molecules leads to new chemical/physical properties and up to now more than 6000 fluorinated substances are on the market. Especially in the field of pharmaceuticals, fluorinated organic molecules are becoming more and more popular and at present amount up to 25% of market share, with an upward trend. Highly fluorinated organic substances are also used in technical applications (e.g., coatings, fire-extinguishing agents, textiles). However, next to beneficial aspects of per- and polyfluorinated compounds (PFAS) these substances belong to the class of “emerging contaminants” in particular due to their high persistence and ubiquitous presence in the environment. Due to the large variety of fluorinated substances and increasing production volumes, it is most likely that numerous and up to date unknown fluorine-species are present in the (aquatic) environment. Sum parameter analytical methods to assess the degree of contamination of surface waters with organically bound fluorine are highly needed.
Within this presentation the development of a high resolution-continuum source-graphite furnace molecular absorption spectrometry (HR-CS-GFMAS) method for PFAS analysis is presented. Fluorine detection is enabled upon the addition of a molecule forming agent – Ga turned out being the most sensitive one. Furthermore, the injection as well as temperature program was optimized, and appropriate solid phase extraction (SPE) phases were identified for PFAS extraction. Our developed HR-CS-GFMAS method turned out as a versatile tool in PFAS analysis in a broad variety of matrices – some recent applications will be highlighted as well.
The global COVID-19 pandemic has brought far-reaching changes for our society. Suddenly, millions of people spent the majority of their time at home - either due to a lock down or by switching from office to working remotely. This paper offers a literature review regarding pandemic-related behavioural changes and a first mapping of likely consequences for EU Ecodesign regulations. These impacts are considered for product groups that are already regulated by EU Ecodesign or are under discussion for future regulation. Furthermore, potential for smart home applications are analysed exemplarily. We identified which behavioural changes have the potential to become established in the long-term. This might need to result in adaptions for regulations under the Ecodesign Directive and EU-Energy Labelling regulations to better reflect the recently appeared usage profiles. It might require different priority settings regarding the product groups to be regulated and communicated to users, due to online shopping proliferation, to be updated. Changed behaviour can be observed in product groups such as ICT, consumer electronics and household appliances. Examples include the increased use of laptops and tablets for digital teaching, use of gaming devices and office equipment in private households (IT, printing and network devices) and changed cooking behaviour. This resulted in increased sales of some product types. Online sales became even more important than in-store sales, which also means that consumers are increasingly informed online about energy efficiency. More do-it-yourself (DIY) home projects result in more frequent - not yet regulated - DIY power tool use and over the long run might stimulate the need for (semi-)professional tools. The changes in behaviour patterns also offer the opportunity to optimize consumption by means of smart homes and smart products. However, the control of networked household appliances requires additional energy for standby states and data exchange. As an illustrative example, we discuss the conflict between higher energy consumption for smart system components and the possible optimization of consumption in private households.
In 2020, the European Commission has announced to propose a Sustainable Product Policy for the EU which shall ensure that the performance of front-runners in sustainability progressively becomes the norm. In addition, the European Commission has re-emphasised the necessity to significantly improve the effectiveness of the current Ecodesign framework for energy-related products.
With this paper, we present an initial outline of a policy approach which we call the “EU frontrunner approach”. The approach aims at installing a regulatory framework which enables a semi-automated, progressive adaptation of ecodesign minimum requirements for products. It builds on performance levels of the best products available on the market by aggregating information in a database.
The “front-runner approach” could first be applied to progressively adapt product-related minimum energy-efficiency requirements. This way it would serve as a starting point to introduce this conceptto the EU policy arena.
While the approach can be applied for energy efficiency, it is neither limited to energy-related products nor to energy-related requirements. It can be applied to the wide range of nonenergy related products within the scope of the upcoming Ecodesign for Sustainable Products Regulation (ESPR) as well as to non-energy-related requirements, such as minimum requirements for durability, reparability, recyclability and recycled content.
Contamination of drinking water with pharmaceuticals is an emerging problem and a potential health threat. Immunochemical methods based on the binding of the analyte to specific antibodies enable fast & cost-effective on-site analyses. Magnetic bead-based immunoassays (MBBAs) allow for implementation into an immunosensor for online testing. Particles are prepared by either coupling the analyte molecule (diclofenac) or the respective antibody (amoxicillin) to the surface. For miniaturization, detection is performed electrochemically (chronoamperometry) on a microfluidic chip. The developed immunosensor will enable detection of pharmaceuticals directly in water supply pipes.
Exposure sites and outdoor exposure have always been a part of atmospheric corrosion research providing the “final answer”, although at the cost of long exposure times. Individual exposure programs such as ISOCORRAG, MICAT and ICP Materials have resulted in collaborative networks of exposure sites. So far, however, there has been no collective effort to put together currently active sites in a comprehensive manner and across programs and nations. The information collected in the catalogue is possible thanks to the work of all individual site managers listed as contact persons, efforts of members of Working Party 25 (WP25) Atmospheric Corrosion of the European Federation of Corrosion (EFC) and financial support of the EFC. With this Catalogue you can both get a general overview of what is available and be guided if you are looking for a particular environment with certain characteristics.
Aim. The European biocidal products regulation requires environmental risk assessments for biocidal products under service conditions. This is only possible, if processes that lead to biocide emissions into the environment are understood and can be reasonably predicted.
Actual emissions due to leaching result from different processes that are affected by material properties and environmental conditions. Transformation of biocides can affect emissions considerably.
Leaching and possible transformation of the film preservatives carbendazim, diuron, OIT and terbutryn in paints was observed under laboratory and field conditons in order to investigate the influence of different factors, e.g. water contact and radiation on biocide emissions. The paints contained either white titanium dioxide or a red iron oxide pigment to check whether pigments affect leaching processes.
Methods. Test specimens of a water-based styrene acrylic dispersion paint on glass were exposed to UVA-radiation in a UV weathering device and/or exposed to water contact by immersion events on the basis of the European standard EN 16105. Plywood panels were coated and exposed to natural weather conditions in a semi-field experiment. Concentrations of biocides and transformation products were analysed in leachates from laboratory tests, runoff samples and remaining coatings.
Results. The impact of weathering conditions on transformation processes differs for the investigated active substances. Water contact, radiation as well as pigments in the paints determine the pattern and amount of transformation products on coatings, leachates and runoff water. Observations from laboratory and field experiments were compared. It proved that results from laboratory tests support understanding of data from field experiments.
Detailed knowledge on the fate of active substances under environmental conditions supports manufacturers to develop safe applications of film preservatives and authorities to evaluate its environmental impact.
Biocides used as material preservatives are in contact with various environments during direct application or passive leaching from protected materials. Antimicrobial resistance (AMR) is a global health problem and the environment is an important compartment for the evolution and transmission of AMR. Soil is an environment with a large reservoir of natural microbial communities and antimicrobial resistance (AMR) genes. Those natural microbial communities are frequently exposed to biocides used as material preservatives. Previous studies have shown that antibiotics, metals and pesticides affect the underlying processes of resistance evolution and spread; namely de novo mutagenesis and horizontal gene transfer by conjugation and transformation in microbial communities. However, it is unknown if active substances used in material preservatives are involved in these processes. We show that biocides used as material preservatives affect rates of mutation and conjugation in microorganism in a species- and substance-dependent manner, while rates of transformation are not directly affected. Our data highlights the importance of assessing the contribution of material preservatives on AMR evolution and spread in the environment.
Near-infrared (NIR) spectroscopy is a promising candidate for low-cost, nondestructive, and highthroughput mass quantification of microplastics in environmental samples. Widespread application of the technique is currently hampered mainly by the low sensitivity of NIR spectroscopy compared to thermoanalytical approaches commonly used for this type of analysis. This study shows how the application of NIR spectroscopy for mass quantification of microplastics can be extended to smaller analyte levels by combining it with a simple and rapid microplastic enrichment protocol. For this purpose, the widely used flotation of microplastics in a NaCl solution, accelerated by centrifugation, was chosen which allowed to remove up to 99 % of the matrix at recovery rates of 83–104 %. The spectroscopic measurements took place directly on the stainless-steel filters used to collect the extracted particles to reduce sample handling to a minimum. Partial least squares regression (PLSR) models were used to identify and quantify the extracted microplastics in the mass range of 1–10 mg.
The simple and fast extraction procedure was systematically optimized to meet the requirements for the quantification of microplastics from common PE-, PP-, and PS-based packaging materials with a particle size < 1 mm found in compost or soils with high natural organic matter content (> 10 % determined by loss on ignition). Microplastics could be detected in model samples at a mass fraction of 1 mg g-1. The detectable microplastic mass fraction is about an order of magnitude lower compared to previous studies using NIR spectroscopy without additional enrichment. To emphasize the cost-effectiveness of the method, it was implemented using some of the cheapest and most
compact NIR spectrometers available.
Fungi that share light-flooded habitats with phototrophs may profit from their excess photosynthetic products. But to cope with sunlight-associated stresses [e.g. high temperatures, UV radiation with associated DNA damage, accumulation of reactive oxygen species (ROS), desiccation and osmotic stresses] it is important for fungi to accurately sense and respond to changes in light. The genomes of black [dihydroxynaphthalene (DHN) melanin-containing] fungi from phyllosphere and exposed solid surfaces contain multiple photoreceptors (PRs). The plant pathogen Botrytis cinerea (Leotiomycetes) has a highly sophisticated photosensory and signalling system that helps to avoid light and to locate susceptible hosts. Rock-inhabiting Dothideomycetes and Eurotiomycetes including Knufia petricola possess equal numbers of PRs along with the same set of protective pigments. This similarity between black fungi from plant and rock surfaces suggests that photoperception and -regulation are important for fungi that receive nutrients through cooperation with phototrophs.
Sunlight is an important environmental factor is almost all ecosystems by being a source of energy, information, and stress. All organisms must protect themselves from the harmful effects of light such as UV radiation, ROS accumulation, heat, and desiccation. Finally, light qualities and quantities can be used for decision making, timing and as guide for directed growth when they are sensed and transduced into intracellular signals. Botrytis cinerea and other plant pathogens infecting the sun-exposed parts of the plant must cope with the high light conditions the host plant seeks. Further they experience an altered light spectrum (‘green gap’) when they colonize shaded parts of the plant; it is depleted for blue and red light that is absorbed by the plant chlorophyll and enriched for green and far-red light that is reflected or transmitted by the plant tissue. As these ambient light conditions trigger the shade avoidance response in the plant, the pathogens may trigger their own ‘shading response’ such as the upregulation of virulence determinants and inoculum production. B. cinerea maintains a highly sophisticated light signaling machinery that senses different light qualities to trigger a variety of responses, that are protection, morphogenesis, positive and negative tropisms, and entrainment. These characteristics render B. cinerea a valuable model to enlighten the role of light in parasitic fungus-plant interactions and beyond. The vegetative mycelium – the core of all infection and developmental programs – is not visibly pigmented and thus considered to be sensitive to biotic and abiotic stresses. However, the vegetative hyphae have a very limited half-life and are usually restricted to the invasive growth phase in which they are protected from light by the plant tissue. Fast colonization of host tissues and by this proper nutrient acquisition enables the rapid formation of long-lasting reproduction structures (melanized conidiophores with conidia, sclerotia) on the surfaces of rotted plant tissues. Depending on the light and temperature conditions, conidiation or sclerotial development is initiated. Taken together, B. cinerea uses light-regulated signaling networks to avoid light whenever possible; for example, by minimizing the half-life of sensitive cells that are hiding in plant tissues and by scheduling critical steps such as conidiogenesis, conidial germination and penetration of plant tissues for the night.
Die passive Probenahme von VOC (Volatile Organic Compounds) mit Tenax® TA und Thermodesorption GC/MS Analytik ist eine einfache, kosteneffiziente und repräsentative Methode zur Bestimmung der VOC-Konzentrationen in der Innenraumluft. In der Theorie ist die Stoffaufnahme in den Passivsammler nur abhängig vom Diffusionskoeffizienten der Substanz in Luft und der Geometrie des Sammlers (ideale Adsorption). Um sie zu charakterisieren, wird die Aufnahmerate (UR), definiert als Quotient der Massenaufnahme und dem Produkt aus Konzentration und Expositionszeit, verwendet. Viele effektive Aufnahmeraten (UR,eff) unterscheiden sich beträchtlich von idealen (theoretischen) Werten (UR,id). Literaturwerte sind in nationalen und internationalen Normen lediglich für bestimmte Expositionszeiten vorgegeben, während detaillierte Informationen über den zugehörigen Konzentrationsbereich fehlen. Außerdem ist die Anzahl der insgesamt in der Literatur beschriebenen Substanzen begrenzt. Das Ziel der vorgestellten Studie ist es diesen Fundus an Aufnahmeraten zu begutachten und zu prüfen und ihn durch die Bestimmung eigener qualitätsgesicherter Laborwerte zu ergänzen. Die bestimmten Aufnahmeraten werden als akkurat bezüglich ihrer relativen Standardabweichung und Vergleichbarkeit zu Literaturwerten betrachtet und können für Expositionszeiten von 7 Tagen bei Konzentrationen von 50 100 µg/m³ (ca. 100 300 ppm min) empfohlen werden. Die Sieben Tage Aufnahmeraten aus ISO16017 2 und ASTM D6196 sind nicht generell für diesen Zweck geeignet, wie exemplarisch für Benzol gezeigt wurde.
Genormte künstliche Bewitterungstests sind häufig nicht spezifisch für die Anwendungssituation oder das Material. Das macht die Entwicklung spezifischer Tests erforderlich. Für deren Entwicklung müssen Maximalparameter der Anwendungssituation bekannt sein, womit dann der künstliche Test formuliert wird und dessen Bedingungen werden dann solange optimiert, bis die Korrelation der Effekte von natürlichem und künstlichem Test ausreichend ist.
Für Untersuchungen der Freisetzung kann der verbleibende Rest in der Probe und/oder die freigesetzte Menge in Luft, Boden, Wasser bestimmt werden.
Im ersten Beispiel der Witterungswirkung wurde die Freisetzung von Kohlenstoff-Nanoröhrchen (CNT) aus Polymer-Kompositen untersucht (unter Verwendung von empfindlich-nachweisbarer radioaktiver 14C-Markierung für einzelne CNT-Partikel), in einem zweiten die Freisetzung von anorganischen und organischen Bestandteilen aus elastomeren Bestandteilen von Sportböden (Bahnen und Kunstrasen) in Wasser.
The main obstacle to bottom ash (BA) being used as a recycling aggregate is the content of salts and potential toxic elements (PTEs), concentrated in a layer that coats BA particles. This work presents a dry treatment for the removal of salts and PTEs from BA particles. Two pilotscale abrasion units (with/without the removal of the fine particles) were fed with different BA samples. The performance of the abrasion tests was assessed through the analyses of particle size and moisture, and that of the column leaching tests at solid-to-liquid ratios between 0.3 and 4. The results were: the particle-size distribution of the treated materials was homogeneous (25 wt % had dimensions <6.3 mm) and their moisture halved, as well as the electrical conductivity of the leachates. A significant decrease was observed in the leachates of the treated BA for sulphates (44%),
chlorides (26%), and PTEs (53% Cr, 60% Cu and 8% Mo). The statistical analysis revealed good correlations between chloride and sulphate concentrations in the leachates with Ba, Cu, Mo, and Sr, illustrating the consistent behavior of the major and minor components of the layer surrounding BA particles. In conclusion, the tested process could be considered as promising for the improvement of BA valorization.
Die Zementindustrie und weitere energieintensive Industrien wie etwa die Stahlindustrie stehen vor dem Hintergrund der Transformation unserer Gesellschaft zur Klimaneutralität vor erheblichen Herausforderungen. Ziel dieser Branchen ist perspektivisch die vollständige Vermeidung klimaschädlicher Emissionen – mit besonderem Fokus auf Kohlendioxid. Neben der Umstellung auf regenerative Energieträger, sind im Speziellen für die Zementindustrie die erheblichen Anteile an CO2-Emissionen durch die Entsäuerung von Kalkstein zukünftig zu vermeiden. Da die hervorragenden Bindemitteleigenschaften des bisher hauptsächlich in Zementen eingesetzten Portlandklinkers jedoch auf Calciumverbindungen wie Tri- und Di-calciumsilikaten basieren, stellt die Substitution des Kalks derzeit für die Zementindustrie die größte Herausforderung dar. Neben vollständig neuen Bindemittelsystemen ohne Verwendung von Kalk und CCS/CCU-Technologien zur Vermeidung der CO2-Emissionen bei Verwendung von Kalk, können Abfälle und Nebenprodukte wie etwa Betonbrechsand, verschiedene Schlacken und weitere Massenreststoffe sinnvoll zur Einsparung von Rohstoffen und zur Vermeidung von CO2-Emissionen eingesetzt werden. Es gilt diese Potentiale von Sekundärrohstoffen branchenübergreifend zu identifizieren und Synergien zwischen den Branchen nutzbar zu machen. Hierbei werden neben der chemischen Zusammensetzung der Abfälle und Nebenprodukte auch die Verfügbarkeit und der Massenstrom relevante Kriterien sein. Die potenziellen Sekundärrohstoffe und deren Gemische mit chemisch ähnlicher Zusammensetzung wie die bisher verwendeten Bindemittel, können durch verschiedene technische Ansätze wieder in reaktive Bindemittel umgewandelt und damit nutzbar gemacht werden. Eine gezielte Umwandlung der nicht reaktiven mineralischen Phasen in neue mineralische Phasen mit guten Bindemitteleigenschaften, kann u. a. durch Schmelzprozesse erzielt werden. In Schmelzen können bei hohen Temperaturen die bestehenden, nicht reaktiven mineralischen Phasen zerstört und neue mineralische Phasen mit guten Bindemitteleigenschaften erzeugt werden. Hohe Freiheitsgrade durch gezielte Einstellung der stofflichen Zusammensetzung der Schmelze, durch Stoffseparationen und durch geregelte Abkühlregimes können eine maßgeschneiderte Erzeugung neuer Bindemitteltypen ermöglichen. Aufgrund der hohen erforderlichen Temperaturen von Schmelzprozessen ist die Umsetzung dieser neuen Verfahren nach Möglichkeit in bestehenden pyrometallurgischen Produktionsrouten wie etwa der Stahlproduktion vorzunehmen. So kann etwa der Einsatz von Betonbrechsand als Schlackebildner in der Stahlproduktion zielführend sein, wenn die Schlacke wieder zu einem Bindemittel prozessiert wird und in Zementen Verwendung findet. Eine stoffliche Kreislaufführung wäre hiermit gegeben, wobei der Einsatz von Kalkstein als Schlackebildner oder Rohstoff für die Zementproduktion, und damit die entsprechenden CO2-Emissionen, vermieden werden. Die Entwicklung neuartiger Bindemittelsysteme auf Basis von Sekundärrohstoffen sollte von erforderlichen Anpassungen und neuen Entwicklungen in der Regelsetzung und Normung begleitet werden. Vor allem muss gewährleistet sein, dass die mit neuen Bindemitteln hergestellten Betone den hohen Anforderungen an Dauerhaftigkeit und Umweltverträglichkeit genügen. Des Weiteren sollte mit den etablierten Methoden, wie etwa der Lebenszyklusanalyse, untersucht werden, inwiefern und in welchem Umfang die neuen technischen Entwicklungen zu Nachhaltigkeit und Klimaschutz beitragen.
Larvae and adults of Korynetes caeruleus (de Geer 1775) (Coleoptera: Cleridae) were collected from old churches and reared in the laboratory on Anobium punctatum (de Geer 1774) (Coleoptera, Ptinidea, formerly Anobiidae). Breeding success of K. caeruleus was low, but basic parameters of this species’ developmental cycle were identified. At 21 °C and 75 % relative humidity and a four-month cold period at 4 °C, the development of K. caeruleus from egg to adult appearance lasted 2 years. The pupal stage may be reached and completed after one and a half years. Feeding on larvae of A. punctatum by larvae of K. caeruleus was observed and consisted of a combination of sucking haemolymph and consuming body parts. The sickle-like mandibles of larvae of K. caeruleus penetrate the cuticle of prey larvae followed by pumping and sucking body movements. Adult beetles of A. punctatum were not attacked by K. caeruleus larvae. Feeding behavior of adult K. caeruleus was not investigated.
Microbiologically Influenced Corrosion of Cast Iron Containers for High-Level Nuclear Waste Disposal
(2022)
Ductile and corrosion resistant cast iron is investigated as a potential container material to store high-level nuclear waste (HLW) in deep geological repositories (DGR) in claystone bedrock. The dynamic corrosion process is dependent on the conditions present in the DGR which are influenced and/or controlled by geochemical parameters (e.g., redox potential, pH, presence of and ionic concentration in (pore-)water), physical parameters (e.g., pressure), and the influence of metabolically active microorganisms. Cast iron corrosion will occur at the intersection of container and its decontaminable coating with the bentonite backfill material which contains natural microbial populations.
The conditions in a DGR are simulated in microcosm experiments to investigate the impact of microbiologically influenced corrosion (MIC); the microcosms contain: B27 bentonite, synthetic pore water, N2 or N2-CO2 atmosphere, cast iron coupons, as well as the bacterium Desulfosporosinus burensis (isolated from repository depth in Buré, France). Three coupon configurations will be used: untreated, coated with decontaminable coating, and coated with decontaminable coating which has been damaged to simulate possible damages. The microcosms will be examined for bio- and geochemical parameters, such as pH, redox potential, mineral phases, sulphate concentration, Fe(II):Fe(III), changes in microbial populations, and the corrosion process for formation of corrosion products, and potential microbial influence, after a 270-day incubation period at 25°C under anaerobic conditions. In subsequent experiments, the sorption behavior of lanthanides and actinides onto the membranes of viable cells and spores of D. burensis, as well as the surface of corroded cast iron coupons will be investigated.
Analyseverfahren und Messhäufigkeit zur Bestimmung des Phosphorgehalts im Klärschlamm nach AbfKlärV
(2022)
Auf dem Betreiberforum der DWA-Plattform P-Rück wurden die Empfehlungen für den Vollzug der Phosphorrückgewinnungspflicht aus Klärschlamm vorgestellt. Diese Empfehlungen behandeln die Häufigkeit der Phosphoruntersuchungen im Klärschlamm, wo ein Jahresgang empfohlen wird und eine Empfehlung der Phosphorbestimmung über Aufschluss der Probe in der Mikrowelle und Messung mit ICP-OES. Untermauert wurden die Empfehlungen mit den Ergebnissen von Klärschlamm-Monitoring, Ringversuch und Analytikvergleich aus dem Vorhaben extraWERT.
For the European sewage sludge ash monitoring ash samples from sewage sludge incineration plants were requested from all over Europe. First results of the received samples regarding main and trace element contents were presented at ESPC4. Moreover, a list of all known European facilities for sewage sludge monoincineration was presented.
11 laser printers from 5 manufacturers were purchased in 2017 and tested for their UFP emissions. Size resolved sampling of the emitted particles was done with a 13 stage (30 nm to 10 µm) low pressure cascade impactor. The sampled particles were analysed for their chemical composition by thermal extraction (vaporization at 290°C) followed by GC-MS analysis. High boiling cyclic siloxanes (D10 to D16) were detected as constituents of UFP from laser printers. In comparison to measurements in 2008, aliphatic long-chain alkanes (C22 to C34) were detected additionally as chemical constituents of UFP from most of the tested printers and their amounts were higher than for cyclic siloxanes. Printers of one manufacturer showed very low UPF emissions compared to the other manufacturers.
Closed material cycles and unmixed material fractions are required to achieve high recovery and recycling rates in the building industry. The growing diversity of construction and demolition waste is leading to increasing difficulties in separating the individual materials. Manual sorting involves many risks and dangers for the executing staff and is merely based on obvious, visually detectable differences for separation. An automated, sensor-based sorting of these building materials could complement or replace this practice to improve processing speed, recycling rates, sorting quality, and prevailing health conditions.
A joint project of partners from industry and research institutions approaches this task by investigating and testing the combination of laser-induced breakdown spectroscopy (LIBS) and visual (VIS)/ near-infrared (NIR) spectroscopy. Joint processing of information (data fusion) is expected to significantly improve the sorting quality of various materials like concrete, main masonry building materials, organic components, etc., and may enable the detection and separation of impurities such as SO3-containing building materials (gypsum, aerated concrete, etc.). Focusing on Berlin as an example, the entire value chain will be analyzed to minimize economic/technological barriers and obstacles at the cluster level and to sustainably increase recovery and recycling rates.
First LIBS measurements show promising results in distinguishing various material types. A meaningful validation shall be achieved with further practical samples. Future works will investigate the combination of LIBS and VIS/NIR spectroscopy in a fully automated measurement setup with conveyor belt speeds of 3 m/s.
11 laser printers from 5 manufacturers were purchased in 2017 and tested for their UFP emissions. Size resolved sampling of the emitted particles was done with a 13 stage (30 nm to 10 µm) low pressure cascade impactor. The sampled particles were analysed for their chemical composition by thermal extraction (vaporization at 290°C) followed by GC-MS analysis. High boiling cyclic siloxanes (D10 to D16) were detected as constituents of UFP from laser printers. In comparison to measurements in 2008, aliphatic long-chain alkanes (C22 to C34) were detected additionally as chemical constituents of UFP from most of the tested printers and their amounts were higher than for cyclic siloxanes. Printers of one manufacturer showed very low UPF emissions compared to the other manufacturers.
Klärschlammaschen können eine hohe Phosphatkonzentration aufweisen und stellen damit einen geeigneten Sekundärrohstoff für die Produktion von Phosphatdüngemitteln dar. Bisher wird dieses Potential der Klärschlammaschen für die Phosphor-Rückgewinnung jedoch kaum genutzt, da die in den Aschen enthaltenen Phosphate für Pflanzen kaum verfügbar und die Aschen teilweise mit toxischen Schwermetallen belastet sind.
Im AshDec®-Verfahren wird die Klärschlammaschen im Drehrohrofen im Temperaturbereich 800-1000°C unter Zugabe von Alkali-Additiven (bsp. Na2CO3) thermochemisch behandelt, um ein wirksames und schadstoffarmes Phosphatdüngemittel herzustellen. Aktuell bereitet die Firma Emter GmbH den Bau der ersten großtechnischen AshDec®-Anlage mit einer Kapazität von 30.000 Jahrestonnen Klärschlammasche am Standort ihrer Klärschlammverbrennungsanlage (Altenstadt / Oberbayern) vor. Die erste Ausbaustufe dieser Anlage wird durch das BMBF-Projekt R-Rhenania im Rahmen der Förderinitiative RePhoR begleitet.
An investigation of microplastic (MP) occurrence in a municipal wastewater treatment plant (WWTP) effluent with tertiary treatment was carried out. Representative sample volumes of 1 m3 were taken by applying a fractionated filtration method (500, 100, and 50 µm mesh sizes). The detection of MP mass fractions by thermal extraction desorption–gas chromatography/mass spectrometry (TED-GC/MS) was achieved without the previously required additional sample pretreatment for the first time. Different types of quantification methods for the evaluation of TED-GC/MS data were tested, and their accuracy and feasibility have been proven for real samples. Polyethylene, polystyrene, and polypropylene were identified in effluent samples. The polymer mass content varied significantly between 5 and 50 mg m−3. A correlation between the MP load and the quantity of suspended matter in the WWTP effluents, particle size distribution, particle type, and operation day (i.e., weekday, season, and capacity) was not found. It can be concluded that a meaningful assessment of WWTPs requires a comprehensive sampling campaign with varying operation conditions.
Emanating from developing flame retarded biocomposites, we have proposed renewable natural fibers (including keratin) taken from industrial waste as an authentic sustainable approach. More recently, we have investigated non-vegan flame retardant approaches. This paper loves to give you an insight into our ongoing projects on biogenic industrial wastes like leather, bone meal, and insects. Materials were characterized multi-methodically, flame retardant modes of action quantified, decomposition mechanism proposed, and synergisms explained. Considering the large quantities of leather waste (LW) in industrial-scale production, we underline LW as multifunctional bio-adjuvants. LW enhances the flame retardancy of poly(ethylene-vinyl acetate) (EVA) containing phosphorus flame retardants (P-FR). Products/by-products of the invertebrate and vertebrate farming, respectively, are promising bio-based adjuvants in flame retarded bio-epoxy thermosets. While the addition of bone meal yields the formation of an inorganic shield, protein-based powders from insects provide an intumescent behavior. In combination with a P-FR superior charring and self-extinguishing are obtained.
Acknowledgement: In part of this work was supported by the Volkswagen Foundation grant “Experiment!” No. 97437.
Drei grundlegend verschiedene Ansätze für Umweltsimulation werden an Beispielen illustriert:
(i) Ganzheitlicher Ansatz - Nachstellen von Umweltmilieus im Labor
Ziel ist hier das Nachstellen von (kombinierten) Umweltbedingungen im Labor; die Umweltparameter werden mit all ihren Wechselwirkungen aufgebracht.
Hauptnutzen ist eine gegenüber der natürlichen Beanspruchung erhöhte Reproduzierbarkeit der Umweltbedingungen. Hat man sein Laborsetup entwickelt, ist es auf verschiedene Materialien anwendbar.
Unter solchen Laborbedingungen ermittelte Lebensdauern sind dabei nicht auf die typischerweise sehr variablen Real-Umweltbedingungen übertragbar.
(ii) Parametrisierter Ansatz - Ermittlung einzelner Materialempfindlichkeiten
Hierbei werden im Labor die Wirkungen separater Umweltparameter auf Materialien nachgestellt. Für eine solche Separation der Einflussfaktoren ist insbesondere die Aufschlüsselung möglicher Wechselwirkungen der Umwelt-parameter (z.B. Mikroklima an bestrahlten Oberflächen) erforderlich. Einzelne (meist Alterungs-) Empfindlichkeiten können qualitativ nachgewiesen werden oder sogar – als Beanspruchungs-Wirkungs-Funktionen – quantifiziert werden, was einen wesentlichen Schritt in Richtung der Digitalisierung der Material¬prüfung darstellt. Insbesondere ist dann auch eine Lebensdauer-vorhersage für vorgegebene Zeitreihen der Beanspruchungs¬parameter umsetzbar.
(iii) Rückwirkungen auf die Umwelt
Umweltbeanspruchungen können zur Freisetzung von Schadstoffen in die Umwelt führen. Durch die Nachstellung kritischer, aber realitätsnaher Einsatzszenarien kann die Menge an freigesetzten Substanzen abgeschätzt werden.
Egal, welcher Ansatz verfolgt wird – ein Vergleich mit der oder einer Real-beanspruchung ist unerlässlich, ebenso wie die Messdatenaufzeichnung (data logging) aller potenziell relevanten Beanspruchungsparameter während dieser Realbeanspruchung.
Obwohl die naturnahe Umwelt – sowohl in der BAM als auch bei der GUS – gegenüber der technischen Umwelt eher untergeordnet auftritt, werden zur Illustration Beispiele aus der naturnahen Umwelt verwendet.
Rechtliche Vorgaben der Klärschlammverordnung und deren Auswirkungen auf die Phosphor-Rückgewinnung
(2022)
Im Abfalltechnik-Ausschuss der Bund/Länder-Arbeitsgemeinschaft Abfall (LAGA) wurde eine Vollzugshilfe zur Klärschlammverordnung erarbeitet, die nach Verabschiedung durch die Umweltministerkonferenz Mitte Mai 2020 als LAGA-Merkblatt M-39 veröffentlicht wurde. Im vorliegenden vierten Arbeitsbericht der DWA-Arbeitsgruppe KEK-1.1 werden verschiedene Aspekte der ab dem Jahr 2029 geltenden Regelungen aufgegriffen und damit einige Punkte des LAGA M-39 hinsichtlich der technischen Auswirkungen für den Kläranlagenbetreiber konkret ausgeführt.
Zur Weiterentwicklung der Probenpräsentation wurde ein Adapter entwickelt, der Emissionsprüfkammer und Bewertungstrichter miteinander verbindet und dadurch eine der direkten Messung vergleichbare Geruchsbewertung ermöglicht. Die analytischen Messungen zeigen, dass es kaum Unterschiede in der Zusammensetzung der Probenluft in der Kammer im Vergleich zum Probenbehälter gibt. Bei den olfaktorischen Messungen kam es jedoch bei der Bewertung der Probenluft mit Hilfe des Adapters zu Minderbefunden. Anschließende Untersuchungen zeigten, dass beim Ausschalten des Geräts Umgebungsluft über den Trichter in den Adapter strömt und zu einer Verdünnung der Probenluft führt. Um dies zu vermeiden, werden derzeit weitere Messungen durchgeführt.
Eine weitere Versuchsreihe wurde durchgeführt, um den Messaufwand bei der Bewertung der empfundenen Intensität zu reduzieren. Die entwickelte „größer-oder-kleiner/gleich“ Abfrage kann hier hilfreich sein. Die Untersuchungen im Luftqualitätslabor und im Rahmen eines Ringversuches mit verschiedenen Laboren, zeigen, dass die Abfrage in fast allen Fällen zu den gleichen Ergebnissen führt, wie die normgerechte aber aufwendigere Ermittlung der empfundenen Intensität mithilfe des Vergleichsmaßstabes.
Das Grundproblem der heute verfügbaren und normativ geregelten Prüfverfahren für Zinküberzüge besteht neben den realitätsfernen Prüfbedingungen vor allem in der subjektiv geprägten Auswertung der Prüfergebnisse. Die systematische Betrachtung der Entwicklungen der letzten Jahre zeigt, dass die üblichen Verfahren den aktuellen Anforderungen damit schon vom Ansatz her nicht gerecht werden können und auch die bisher betriebene, fortlaufende Variation und Anpassung von Prüfbedingungen keinen grundlegend neuen Lösungsansatz bieten können. Ein solcher ergibt sich nur, wenn die Zinküberzüge hinsichtlich der kinetischen Eigenschaften der Deckschichtbildung und -auflösung umfassend beschrieben werden können, was nur durch den Einsatz elektrochemischer Untersuchungsmethoden mittels Gelelektrolyten möglich ist.
Aus diesem Grund wurde im Verbundforschungsvorhaben GELELEK auf der Basis elektrochemischer Methoden unter Verwendung eines Gelelektrolyten ein Normenvorschlag für eine Prüfnorm erarbeitet und zur Normungsreife geführt, welcher den Anforderungen an ein Messsystem für Feldanwendungen entspricht.
Im Verbundforschungsvorhaben GELELEK wurde eine gezielte Kombination von Laboruntersuchungen mit Untersuchungen im Feld und Bauteilen unter realen Einsatzbedingungen angestrebt. Randbedingungen für eine gesicherte Messung von atmosphärisch bewitterten Zinküberzügen unter Einsatz von Gelelektrolyten wurden erarbeitet und im Normenvorschlag festgeschrieben. Darüber hinaus wurde ein mobiles Messgerät für Messungen mit Gelelektrolyten an realen Bauteilen entwickelt. Nach Abschluss des Forschungsvorhabens steht Industrievertretern und Prüfinstituten ein wissenschaftlich gesichertes Messverfahren basierend auf Kennwerten zur Verfügung, um Zinküberzüge und deren momentane Schutzwirkung unter praxisrelevanten Bedingungen einschätzen und normativ geregelt prüfen zu können.
Der vorliegende Forschungsbericht gibt einen Überblick über die Motivation zur Durchführung des Forschungsvorhabens, wichtige Arbeitsschritte, Details zur entwickelten Prüfmethode sowie Einsatzmöglichkeiten für Prüfinstitute und Unternehmen.