Enzymatische Umsetzung von Arsenkampfstoffen durch das Pilzenzym Mangan-Peroxidase

Das Pilzenzym Mangan-Peroxidase wurde eingesetzt, um verschiedene Arsenkampfstoffe in zellfreien Reaktionsans?tzen (in vitro) abzubauen. Die Konzentrationsabnahme der Arsenkampfstoffe wurde nach Thiol-Derivatisierung mittels Gaschromatographie geprüft. Alle untersuchten arsenorganischen Verbindungen wurden von der Mangan-Pero-xidase bei Raumtemperatur zu mehr als 90% umgesetzt. Aliphatische Arsenkampfstoffe wurden schneller angegriffen als aromatische Derivate.     

Bodenkontaminationen in Rüstungsaltlasten aus dem Ersten Weltkrieg

The results of the chemical analysis of soil samples from WWI munition plants showed that the most important compounds are dinitrobenzenes, trinitrotoluene and metabolites, and dinitronaphthalenes. The presence of 1,2-dinitrobenzene and 1,3-dinitrobenzene in soil samples shows that, during the production of dinitrobenzenes, in WWI, the raw dinitrobenzene was not washed with sulphite. The results show that the parameter list must be different from the parameter list for the analysis of soil samples from munition plants of WW II.     

Understanding the total life cycle cost implications of reusing structural steel

Reuse of structural steel could be an environmentally superior alternative to the current practice, which is to recycle the majority (88%) of scrap steel. In spite of the potential benefits, and in a time when “sustainability” and “climate change” are critical societal issues, the question arises: why are greater rates of structural steel reuse not being observed? One of the major factors in the rate of structural steel reuse is how decision-makers understand the life cycle implications of their choice to recycle steel rather than reuse it. This paper contributes towards our understanding of these implications, particularly the cost implications, of reuse as an alternative to recycling by presenting a streamlined life cycle analysis and identifying the major contributors to each process. The results of a case study indicate that a significant reduction in some life cycle impact metrics (greenhouse gas emissions, water use) can result from reusing structural steel rather than recycling it. The largest contributors to the life cycle impact of recycling were the shredding, melting, and forming sub-processes. The largest contributor to reuse was the deconstruction sub-process. A total life cycle cost analysis is performed to understand the cost of damages to the environment and human health in combination with the cost of construction activities. Sensitivity and uncertainty analyses are also conducted to quantify variability in the results and determine economic conditions where the two processes have an equal cost.     

Direct N2O emission from agricultural soils in Poland between 1960 and 2009

Nitrogen fertilization (N) is commonly known as a main source of direct nitrous oxide (N₂O) emission from agricultural soils. An area of 38 % of the total land surface of Poland was covered by agricultural soils in 2009. In this paper, we aimed at analyzing data regarding the land exploitation for 13 selected subareas of Poland between 1960 and 2009. Seven out of the 13 subareas studied are located in the West (area A), and six subareas are located in southeast of Poland (area B). The total area covered by large farms (>20 ha) differed largely, between area A (10.6 %) and area B (0.9 %) in 2009. Both areas varied in terms of the amount of fertilizers used annually, average crop yield and crop structure. Average direct emissions of N₂O from agricultural soils were 1.66 ± 0.09 kg N₂O–N ha^?1 a^?1 for area A, 1.39 ± 0.07 kg N₂O–N ha^?1 a^?1 for area B and 1.46 ± 0.07 kg N₂O–N ha^?1 a^?1 for the whole country between 1960 and 2009.     

Development of artificial neural network based metamodels for inactivation of anthrax spores in ventilated spaces using computational fluid dynamics

Linear, quadratic, and artificial neural network (ANN)-based metamodels were developed for predicting the extent of anthrax spore inactivation by chlorine dioxide in a ventilated three-dimensional space over time from computational fluid dynamics model (CFD) simulation data. Dimensionless groups were developed to define the design space of the problem scenario. The Hammersley sequence sampling (HSS) method was used to determine the sampling points for the numerical experiments within the design space. A CFD model, comprised of multiple submodels, was applied to conduct the numerical experiments. Large eddy simulation (LES) with the Smagorinsky subgridscale model was applied to compute the airflow. Anthrax spores were modeled as a dispersed solid phase using the Lagrangian treatment. The disinfectant transport was calculated by solving a mass transport equation. Kinetic decay constants were included for spontaneous decay of the disinfectant and for the reaction of the disinfectant with the surfaces of the three-dimensional space. To enhance the mixing of the disinfectant with the room air, a momentum source was included in the simulation. An inactivation rate equation accounted for the reaction between the spores and the disinfectant. The ANN-based metamodels were most successful in predicting the number of viable bioaerosols remaining in an arbitrary enclosed space. Sensitivity analysis showed that the mass fraction of the disinfectant, inactivation rate constant, and contact time had the most influence on the inactivation of the spores.     

Elevated radioxenon detected remotely following the Fukushima nuclear accident

We report on the first measurements of short-lived gaseous fission products detected outside of Japan following the Fukushima nuclear releases, which occurred after a 9.0 magnitude earthquake and tsunami on March 11, 2011. The measurements were conducted at the Pacific Northwest National Laboratory (PNNL), (46°16′47″N, 119°16′53″W) located more than 7000 km from the emission point in Fukushima Japan (37°25′17″N, 141°1′57″E). First detections of ¹³³Xe were made starting early March 16, only four days following the earthquake. Maximum concentrations of ¹³³Xe were in excess of 40 Bq/m³, which is more than ×40,000 the average concentration of this isotope is this part of the United States.     

Electric vehicles: solution or new problem?

Since electric vehicles (EVs) have been recognized as a technology that reduces local air pollution while improving transport energy security, they have been promoted in many countries. Yet, mainly due to their high costs, especially in the case of pure battery electric vehicles, and a lack of proper infrastructure, the use of EVs is still very limited. In this paper, some of the major barriers and the future challenges are discussed. The current problems are mainly attributed to two categories: (1) the battery performances and costs, as well as battery production including issue of material availability and (2) environmental benefits of EVs depending on the sources used for the electricity generation and their carbon intensity. The major conclusions are that (1) research and development with respect to batteries has by far the highest priority and (2) it has to be ensured that the electricity used in EVs is generated largely from renewable energy sources.     

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