4 Material und Umwelt
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- 2019 (109) (entfernen)
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- Corrosion (8)
- Ink (8)
- MIC (8)
- Methanogens (6)
- Archaeometry (4)
- Bauprodukte (4)
- Emission (4)
- XRF (4)
- Coptic (3)
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Organisationseinheit der BAM
- 4 Material und Umwelt (109)
- 4.5 Kunst- und Kulturgutanalyse (33)
- 4.2 Material-Mikrobiom Wechselwirkungen (25)
- 4.1 Biologische Materialschädigung und Referenzorganismen (21)
- 4.4 Thermochemische Reststoffbehandlung und Wertstoffrückgewinnung (17)
- 4.0 Abteilungsleitung und andere (14)
- 6 Materialchemie (8)
- 4.3 Schadstofftransfer und Umwelttechnologien (7)
- 1 Analytische Chemie; Referenzmaterialien (5)
- 6.1 Oberflächen- und Dünnschichtanalyse (4)
- 6.2 Material- und Oberflächentechnologien (3)
- 9 Komponentensicherheit (3)
- 9.3 Schweißtechnische Fertigungsverfahren (3)
- 1.1 Anorganische Spurenanalytik (2)
- 1.2 Biophotonik (2)
- 1.4 Prozessanalytik (2)
- 1.7 Organische Spuren- und Lebensmittelanalytik (2)
- 1.8 Umweltanalytik (2)
- 6.6 Physik und chemische Analytik der Polymere (2)
- 8 Zerstörungsfreie Prüfung (2)
- 8.0 Abteilungsleitung und andere (2)
- 8.5 Röntgenbildgebung (2)
- 1.9 Chemische und optische Sensorik (1)
- 5 Werkstofftechnik (1)
- 5.4 Multimateriale Fertigungsprozesse (1)
- 7 Bauwerkssicherheit (1)
- 7.5 Technische Eigenschaften von Polymerwerkstoffen (1)
- 8.4 Akustische und elektromagnetische Verfahren (1)
Eingeladener Vortrag
- nein (109)
Gegenstand der vorzustellenden Arbeiten ist die Prüfung der Umwelt-beständigkeit und -verträglichkeit von Materialien und Produkten hinsichtlich der Emission von potenziellen Schadstoffen in die Umwelt. Hierzu werden chemisch-physikalische Einflüsse (Bewitterung) und mikrobielle Beanspruchungen an Modellmaterialien evaluiert. So werden die Freisetzungsraten von Schadstoffen in Abhängigkeit der Beanspruchung beschrieben. Als Modellmaterialien kommen die Polymere Polystyrol (PS) und Polypropylen (PP) zum Einsatz. Synergistische Effekte der Bewitterungsparameter und der mikrobiologischen Beanspruchung sollen dabei ebenso betrachtet werden, wie die gezielte Alterung. Auch findet eine Beschreibung des Verhaltens der ausgetragenen Schadstoffe (polybromierte Flammschutzmittel) in den Umweltkompartimenten Boden oder Wasser statt. Hier sind mit Hilfe der zu entwickelnden Screening- und non-Target-Analyseverfahren die Transformation und der Metabolismus durch Mikroorganismen zu beschreiben. Aus den Ergebnissen sollen Korrelationen zwischen den künstlichen Alterungsverfahren und realen Szenarien abgeleitet werden.
Das Prozessmonitoring stellt einen wichtigen Baustein für eine Qualitätssicherung additiv gefertigter Bauteile dar, insbesondere bei kleinen Losgrößen. Der Vortrag zeigt einen Überblick aktueller Entwicklungen der BAM im Bereich des Prozessmonitorings für das Laserstrahlschmelzen (laser powder bed fusion) metallischer Werkstoffe. Durch Vergleich mit der Referenzmethode Computertomografie wird am Beispiel der thermografischen Verfahren gezeigt, wie relevante Defekte in Bauteilen detektiert werden können und Einsatzpotenziale sowie Limitierungen aufgezeigt.
Biocide mitigation strategies of microbiologically influenced corrosion (MIC) in the oil and gas industry have been primarily used to eliminate the growths of sulfate-reducing microorganisms (SRM). However, methanogenic Archaea (MA) can also be highly corrosive by using iron as an electron source for methanogenesis. Because of the fundamental physiological differences between archaea and bacteria, responses of MA towards SRM-specific biocides cannot be deduced using SRM. Due to the lack of information available on the effect of biocides on corrosive MA, we selected THPS, glutaraldehyde, nitrate and perchlorate to compare against corrosive SRM.
Preliminary results showed that at low concentrations of THPS (0-10 ppm), growth of MA was not affected, methane production and corrosion rates (0.1 mm/yr) were comparable between the different THPS concentrations. On the contrary, the SRM strain showed decreased corrosion rates (0.18 mm/yr to 0.03 mm/yr) with increasing THPS concentrations. Further corrosion tests including electrochemical measurements of different biocides on the growth of MA and SRM will be conducted. Such knowledge not only provide important insights on the physiological response of MA to biocides but also contribute to more effective mitigation strategies that can be both economic and environmentally beneficial.
Environmental sustainability and –stability of materials concerning the migration of pollutants
(2019)
In addition to previously reported results on the accelerated weathering of polystyrene samples (PS) containing 1 wt. % hexabromocyclododecane (HBCD), we present the first results of our investigations of polypropylene samples (PP) containing 0.1 wt. % BDE-209. All studied polymer samples were exposed to a defined weathering schedule in a climate chamber in accordance to regulation EN ISO 4892-3:2006. For the determination of BDE-209 in the collected raining water the samples were prepared in accordance to a validated protocol. Before the analyses each sample was spiked with isotopically labeled BDE-209. Subsequently the samples were extracted with isooctane. The obtained extracts were concentrated, and the resulting solutions were analyzed by GC/MS. Additionally, the total bromine content was monitored for the weathered and untreated samples using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and X-ray fluorescence analysis (XRF) as a non-destructive and rapid method. In general, the resulting data from the accelerated weathering will be compared to those from the natural weathering experiments. Here, the surfaces of the test pieces were analyzed by LA-ICP-MS and XRF as well. Moreover, soil bed tests were conducted in a well characterized model soil. This soil (boulder-clay, sand with 12 % loam, particle size in total 0.2-4 mm) is filled in a free-draining basin inside of an air-conditioned cellar. In this manner, TOC, water capacity and humidity are recorded parameters. To induce a leaching process from the samples by the raining water, the target water content is calculated to 8%. The actual humidity is measured by a tensiometer, assuring the duration of the raining period. A defined humidity is a fundamental parameter for a biological activity in the soil. The test polymers were placed up to the half in the soil. Microbial activity of the soil is monitored by a reference polymer (polyurethane) and should induce the release of HBCD and BDE-209 out of the test materials. These released analytes will be captured by passive samplers (silicone tubes) placed in a distinct distance to the polymer samples in the soil. The soil bed experiments are complementary to the weathering experiments due to the biological activity in the soil.
Eine Vielzahl unterschiedlicher Materialien findet für die Gestaltung von Zeichnungen Verwendung. So sind es insbesondere „braune Tinten“, welche die Zeichnungen dominieren. Der Vortrag möchte zunächst einen kurzen Überblick über die Terminologie und die Kunsttechnologie farbiger Tinten geben, um den Kosmos dieser Vielfältigkeit und auch deren Vergänglichkeit zu illustrieren.
Der zweite Teil des Vortrags ist dann den sogenannten Bistertinten und deren analytischen Nachweisen gewidmet. Es handelt sich um Zeichentinten, die aus den wasserlöslichen Bestandteilen von Kaminruß gewonnen werden. Die farbliche Bandbreite reicht von gelb-orange bis braun. Zuweilen wurden diese Tinten mit weiteren Pigmenten versetzt, um eine bestimmte Farbtiefe zu erzielen.
Microbiologically induced corrosion due to bacterial biofilms causes several problems in industrial systems, technical applications and in medicine. Prior to the formation of a biofilm on a substrate, planktonic cells attach on the surface. Hence, the properties of the surface play a key role in biofilm formation and are of great importance for the development of strategies to prevent bacterial attachment and biofilm formation.
This project aims at clarifying to which extent surface micro-/nanostructuring and chemical functionalization affects bacterial attachment and whether a synergistic combination of the two can be used to control bacterial adhesion. To answer these questions, model surfaces with regular patterns of 5-10 micrometers in size have been prepared, which provide distinct zones differing in terms of their chemistry or nano-roughness. This was achieved by micro contact printing of self-assembled monolayers with different functional groups and deposition of patterned ZnO nanorod arrays for studying the effect of surface chemistry and morphology, respectively. Typical contrasts studied were combinations of positively/negatively charged, hydrophobic/hydrophilic or flat/rough.
The attachment behavior of bacteria on tailored surfaces were studied in a flow chamber as a function of time. The strain Pseudomonas fluorescens SBW25 was chosen as a model organism. DNA-intercalating dyes such as Syto9 have a high affinity to adsorb on ZnO nanorods. To overcome this limitation a genetic modification was performed by introducing a gene which expresses a green fluorescent protein in P. fluorescens SBW25 enabling the quantitative evaluation of the flow chamber studies by means of fluorescence microscopy. Further analysis of the attachment behavior was performed by means of scanning electron microscopy.
The presentation will summarize the results of our systematic study on the role of individual parameters on bacterial attachment and highlight synergistic combinations, showing an inhibition or enhancing effect. As the investigations with model substrates enable a precise control of the surface parameters, this approach can be applied to different microorganisms and material systems to achieve a correlative description of bacterial adhesion on solid surfaces.
Normativ ist der Holzschutz in Deutschland durch die DIN 68800-Reihe geregelt. Die Normungsarbeit in CEN/TC 38 bildet dafür den Rahmen, der national angepasst und fachspezifisch erweitert wurde. Zusammen mit dem Kommentar ergeben beide ein in Europa einzigartiges Regelkompendium im Holzschutz. In Zukunft wird die Regelsetzung noch stärker durch internationale Zusammenarbeit bestimmt sein. Der interkontinentalen Marktöffnung sollten Verständigungen auf gemeinsame Qualitätsstandards vorausgehen.
Fungi that share light-flooded habitats with phototrophs may profit from excess photosynthetic products. But to cope with sunlight-associated stresses it is important for fungi to accurately sense and respond to changes in light. To test the hypothesis that light is an environmental cue that Ascomycota use to coordinate growth, stress responses as well as to establish pathogenic or symbiotic relationships, the photoreceptor (PR) distribution in species from different ecological niches was analysed. The genomes of black fungi from phyllosphere and exposed solid surfaces contain multiple photoreceptors (PRs). The filamentous foliar 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 Dothideo- 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 photoregulation are important for fungi that avoid loss of energy and nutrients through cooperation with phototrophs.
Fungi that share light-flooded habitats with phototrophs may profit from excess photosynthetic products. But to cope with sunlight-associated stresses it is important for fungi to accurately sense and respond to changes in light. To test the hypothesis that light is an environmental cue that Ascomycota use to coordinate growth, stress responses as well as to establish pathogenic or symbiotic relationships, the photoreceptor (PR) distribution in species from different ecological niches was analysed. The genomes of black fungi from phyllosphere and exposed solid surfaces contain multiple photoreceptors (PRs). The filamentous foliar 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 Dothideo- 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 photoregulation are important for fungi that avoid loss of energy and nutrients through cooperation with phototrophs.
Untersuchungen von Zeichnungen und Manuskripten mit zerstörungsfreien Methoden haben in den letzten Jahren enorm zugenommen. Die nicht-invasiven Analysen ermöglichen Informationen zur Herkunft, zum Herstellungsprozess und möglicherweise zum Alter (direkte Dating nicht möglich, Ausnahme: Papierstruktur, Wasserzeichen). Die zerstörungsfreien Analysen können Rückschlüsse auf mögliche Fälschungen geben, sind neben den offensichtlichen Vorteilen jedoch auch mit einzelnen Limitierungen behaftet. Der Vortrag soll anhand einiger Fallbeispiele die Möglichkeiten aber auch Grenzen bei der zerstörungsfreien (mobilen) Auffindung von Fälschungen aufzeigen.
A broad suite of immune adaptations have evolved in social insects which hold close parallels with the immune systems of multicellular individuals. However, comparatively little is known about the evolutionary origins of immunity in social insects. We tackle this by identifying immune genes from 18 cockroach and termite species, spanning a gradient of social lifestyles. Termites have undergone contractions of major immune gene families during the early origin of the group, particularly in antimicrobial effector and receptor proteins, followed by later re-expansions in some lineages. In a comparative gene expression analysis, we find that reproductive individuals of a termite invest more in innate immune regulation than other castes. When colonies encounter immune-challenged nestmates, gene expression responses are weak in reproductives but this pattern is reversed when colony members are immune-challenged individually, with reproductives eliciting a greater response to treatment than other castes. Finally, responses to immune challenge were more comprehensive in both subsocial and solitary cockroaches compared to termites, indicating a reduced overall ability to respond to infection in termites. Our study indicates that the emergence of termite sociality was associated with the evolution of a tapered yet caste-adapted immune system.
Results suggest a reduction in immune gene repertoires in termites and possible complementary expression between termite castes. With comparative genomics we will investigate the evolution of gene families related to immunity, try to understand where reductions and expansions take place and relate these changes to shifts in sociality and ecology. The role of TEs in expansions and contractions of immune gene families will be investigated. For these analyses, we propose to generate high quality, highly contiguous genomes of species from different levels of sociality, covering all major termite families. With comparative transcriptomics we will investigate the expression of immune genes in different castes. Via network analyses we will identify pathways indicated in differential immunity between castes and between species of different sociality levels. We will investigate how these pathways have been rewired along the transitions to higher levels of sociality and how, intra-specifically, they change between castes.
Social insects nesting in soil environments are in constant contact with entomopathogens and have evolved disease resistance mechanisms within a colony to prevent the occurrence and spread of infectious diseases. Among these mechanisms: mutual grooming reduces the cuticular load of pathogens, and burial of cadavers and cannibalism can prevent pathogens from replicating within the group. We explored how the rate and type of collective behavioural response is determined by stepwise infection dynamics operating at the level of the individual. Specifically, we infected the eastern subterranean termite Reticulitermes flavipes with different types of infectious particle and infection route of the entomopathogenic fungus Metarhizium anisopliae and recorded behavioural responses of nestmates to individuals at different times during the progression of infections. As expected, termites groomed conidia-exposed individuals significantly more than controls. Interestingly, grooming was significantly elevated after fungal germination than before, suggesting that pathogen growth cues act as strong stimulators of allogrooming. Conidia-exposed termites were cannibalized, but only after they became visibly ill. By contrast, termites did not groom blastospore-injected individuals more than controls at any time-point following infection. Instead, we found that blastospore-injected individuals were continually cannibalized at a low-level following injection with either viable or heat-killed blastospores, with a marked increase in cannibalism after termites injected with viable blastospores became visibly ill and were close to death. Together, these findings point to the importance of host condition as a cue for social hygienic behavior, and that the host itself appears to emit essential sickness cues that act as targets for its own sacrifice. This demonstrates that termites have independently evolved to both identify and destructively respond to sickness.
The termites are a derived eusocial lineage of otherwise non-social cockroaches. Understanding the proximal and ultimate drivers of this major evolutionary transition represents an important goal in biology. One outstanding question concerns the evolution of termite immunity, which is thought to have undergone broad-sweeping adaptations in order to enhance group-level immune protection. To understand the evolutionary origins of termite immunity, we conducted qualitative and quantitative transcriptome analyses along a gradient of sociality. Firstly, we aimed to identify large-scale genetic shifts in immune traits linked to eusociality by comparing immune gene repertoires in solitary and subsocial cockroaches and across a range of eusocial termite lineages. Secondly, we compared the responses of a solitary cockroach, a subsocial wood-roach and different castes of a lower termite species to a non-specific immune challenge, in order to understand how sociality may have influenced the evolution of immune gene regulation. Firstly, we found that termites have a broadly representative repertoire of canonical immune genes as compared to gregarious cockroaches and subsocial wood-roaches. Secondly, with respect to immune challenge, the solitary cockroach and the subsocial wood-roach displayed a similarly comprehensive induced response, while the termite response was considerably dampened by comparison and strongly influenced by caste; with reproductives displaying a generally higher constitutive level of immune-gene expression compared to sterile castes. In summary we did not find termite eusociality to be associated with significant changes in immune gene diversity, but rather to be linked with significant modifications to the regulation of immunity following the origin of division of labour.
In arid sun-exposed environments, rock-inhabiting fungi dominate microbial communities on rock surfaces. Fungi are known to enhance rock weathering, although the exact mechanisms are not completely understood. These natural processes can be simulated by reproducible experimental systems. Particularly attractive are genetically amenable rock-weathering fungi, where certain traits can be knocked-out to identify weathering-relevant functions. Here, we studied the effect of the rock-inhabiting fungus Knufia petricola A95 and its melanin-deficient mutant (ΔKppks) on the weathering of a Fe-bearing olivine. We examined the olivine dissolution kinetics and looked at the olivine-fungus interface. For the former we inoculated olivine powder with the fungus in batch and mixed flow reactors and analysed the medium solution by ICP-OES, for the latter biofilm-covered olivine sections from flow-through reactors were analysed by FIB-TEM.
In general olivine dissolution was lower when olivine was incubated without fungi: the abiotic olivine dissolution rates were lowest and the surface of the abiotically reacted olivine sections showed no etching. Various chemical analyses show Fe (oxyhydr)oxide precipitation on top of the abiotically reacted olivine, indicating its role in inhibiting olivine dissolution. Both the wild type (WT) and ΔKppks solubilised and bound significant amounts of Fe released by olivine dissolution. Fe (oxyhydr)oxide precipitation was thus reduced, explaining the enhanced olivine dissolution in their presence. Particularly efficient at preventing Fe precipitation were attached WT cells: the inhibition of olivine dissolution almost completely disappeared. The attachment capacity of the WT is most likely caused by the production of WT-specific extracellular polymeric substances. Our presented experimental systems allowed the precipitation of Fe (oxyhydr)oxides and included a rock-inhabiting fungus and thus simulated weathering processes relevant to natural ecosystems.
Vorstellung des REFOPLAN-Projekts extraWERT Erhebung zusätzlicher Wertstoffpotenziale in Klärschlamm
(2019)
Auf dem Regionalgruppentreffen wurden erste Projektergebnisse vorgestellt und die Probenahmestrategie diskutiert. Vorgestellt wurde eine Rückberechnung der mittleren Wertstoffgehalte aus dem Klärschlamm-Monitoring 2014 (Krüger und Adam) und erste Auswertungen der Klärschlammbericht-Rohdaten aus NRW und Hessen.
Im Projekt extraWERT geht es um die Ermittlung von Nährstoffpotenzialen in Abwasser und Klärschlamm. Neben kommunalen Kläranlagen soll auch die Industrie als Quelle für nährstoffreiche Abfallströme betrachtet werden. Mit dem Vortrag sollten Mitglieder des MIV zu einer Projektbeteiligung bewegt werden. Es sollen rohes und gereinigtes Abwasser von direkt einleitenden Betrieben auf Makronährstoffe untersucht werden, neue Erkenntnisse werden insbesondere für die Nährstoffe Calcium und Magnesium erwartet.
Die landwirtschaftliche Klärschlammverwertung ist in der Bundesrepublik Deutschland seit Jahren rückläufig. Neben den Risiken durch Schadstoffeinträge gibt es in Deutschland Regionen mit einem stark erhöhten Nährstoffüberschuss. Um die Grundwasserbelastung zu verhindern wurde u.a. das Düngerecht verschärft, was die Flächenkonkurrenz zwischen Klärschlamm und Wirtschaftsdünger vergrößern wird.
Es ist davon auszugehen, dass sich die neuen Regelungen im Düngerecht und der Klärschlammverordnung massiv auf die landwirtschaftliche Verwertung von Klärschlamm und damit auf die Kreislaufwirtschaft verschiedener Nährstoffe auswirken werden. In diesem Beitrag werden erste Ergebnisse des Projekts extraWERT vorgestellt.
Der mitteleuropäische Mensch hält sich 80 – 90 % der Zeit in Innenräumen auf. Je nach Aktivität atmet er 10 – 20 m³ bzw. 12 - 24 kg Luft täglich, das ist weit mehr als das Doppelte der Summe an Essen und Trinken. Die technischen Voraussetzungen für die Bestimmung von Emissionen aus Bauprodukten in die Luft liegen vor – harmonisierte horizontale Prüfnorm EN 16516. Es dürften mittlerweile zig-tausende Emissionsdatensätze vorliegen. Defizite gibt es bei der Kennzeichnung zur Unterscheidung emissionsarmer und emissionsreicher Produkte, die bestehende CE-Kennzeichnung ist unvollständig, ersatzweise gibt es nationale Regelungen.
Gerade bei modernen, dichten Bauten mit geringem natürlichen Luftwechsel sind hohe Schadstoffkonzentrationen zu erwarten, wenn nicht emissionsarme Materialien und Produkte zum Einsatz kommen.