The University of Natural Resources and Life science, Vienna, or simply BOKU , founded in 1872, is an "an education and research centre for renewable resources" in Vienna. There are currently around 12,000 students enrolled at BOKU. Wikipedia.
Salhofer S.,University of Natural Resources and Life Sciences, Vienna
Journal of Hazardous Materials | Year: 2011
Minimum treatment requirements for waste electrical and electronic equipment (WEEE) established by Directive 2002/96/EC provide for the removal of specific components containing hazardous substances. To date, no comparative analysis of removal rates has been undertaken. The present paper examines the state of de-pollution of sWEEE in Austrian treatment plants. The mass of selected components removed and the corresponding mass of hazardous substances is compared to estimated values for sWEEE input material. The results obtained reveal that components are only partly removed, featuring a high variation between components and plants assessed. The overall rate of removal ranged from 72% of the estimated value for batteries to 21% of the estimated value for liquid crystal panels. This implies the forwarding of substantial quantities of hazardous substances to mechanical treatment processes, particularly relevant in terms of dispersion of pollutants. Furthermore, easily releasable pollutants, such as Hg from LCD-backlights, Cd from batteries or highly contaminated dust in general, pose substantial health risks for plant workers. Low removal rates of printed circuit boards, batteries and toner cartridges also lead to a reduction in quantities of valuable recyclable materials (precious metals, plastics). © 2010 Elsevier B.V.
Atzberger C.,University of Natural Resources and Life Sciences, Vienna
Remote Sensing | Year: 2013
Many remote sensing applications are devoted to the agricultural sector. Representative case studies are presented in the special issue "Advances in Remote Sensing of Agriculture". To complement the examples published within the special issue, a few main applications with regional to global focus were selected for this review, where remote sensing contributions are traditionally strong. The selected applications are put in the context of the global challenges the agricultural sector is facing: minimizing the environmental impact, while increasing production and productivity. Five different applications have been selected, which are illustrated and described: (1) biomass and yield estimation, (2) vegetation vigor and drought stress monitoring, (3) assessment of crop phenological development, (4) crop acreage estimation and cropland mapping and (5) mapping of disturbances and land use/land cover (LULC) changes. Many other applications exist, such as precision agriculture and irrigation management (see other special issues of this journal), but were not included to keep the paper concise. The paper starts with an overview of the main agricultural challenges. This section is followed by a brief overview of existing operational monitoring systems. Finally, in the main part of the paper, the mentioned applications are described and illustrated. The review concludes with some key recommendations. © 2013 by the authors.
Stanzl-Tschegg S.,University of Natural Resources and Life Sciences, Vienna
International Journal of Fatigue | Year: 2014
Ever since high-strength steels were found to fail below the traditional fatigue limit when loaded with more than 108 cycles, the investigation of metals' and alloys' very high cycle fatigue properties has received increased attention. A lot of research was invested in developing methods and machinery to reduce testing times. This overview outlines the principles and testing procedures of very high cycle fatigue tests and reports findings in the areas of crack formation, non-propagating small cracks, long crack propagation and thresholds. Furthermore, superimposed and variable amplitude loading as well as frequency effects are reported. © 2012 Elsevier Ltd. All rights reserved.
Tunega D.,University of Natural Resources and Life Sciences, Vienna
Journal of Physical Chemistry C | Year: 2012
Magnetic, electronic, structural, vibrational, and mechanical properties of mineral goethite (α-FeOOH) at ambient conditions and their dependence on isostatic volume compression (corresponding pressure range 0-80 GPa) have been studied by means of spin-polarized density functional theory (spDFT), modified spDFT+U method, which includes a Hubbard-type on-site repulsion term U, and hybrid DFT functional MSE06. The antiferromagnetic high spin ground state has been confirmed as the most stable at low-pressure conditions. Calculated Fe magnetic moments differ from experiment by about 0.3-0.4 μ B. The antiferromagnetic high spin state is stable over the whole compression range in the spDFT+U and MSE06 calculations. For the spDFT, a collapse from a high spin to low spin state has been induced by compression. In comparison to experiment, the spDFT method strongly underestimates electronic band gap, and the spDFT+U results are in a reasonable agreement (with a difference of 0.1-0.5 eV), while the hybrid MSE06 functional gives an overestimated value. The spDFT+U calculated band gap narrows upon increasing volume compression. Structural parameters calculated by all three methods are in very good agreement with experimental data with an error below 1-1.5%. The analysis of structural parameters has shown that the compression proceeds mainly through the compression of structural channels containing hydrogen bonds. Very narrow splitting in a range of ∼20 cm -1 has been found for the calculated OH stretching modes. The predicted bulk modulus of 114.3 GPa (spDFT+U) is in accord with an experimental value of 111 GPa. The calculated elastic constants document an anisotropic character of the single crystal structure of goethite. In general, the spDFT+U provides reliable results for all studied properties, while the MSE06 overestimates some of them (e.g., band gap). © 2012 American Chemical Society.
Steyaert S.M.,University of Natural Resources and Life Sciences, Vienna
Biology letters | Year: 2013
Behavioural strategies to reduce predation risk can incur costs, which are often referred to as risk effects. A common strategy to avoid predation is spatio-temporal avoidance of predators, in which prey typically trade optimal resources for safety. Analogous with predator-prey theory, risk effects should also arise in species with sexually selected infanticide (SSI), in which females with dependent offspring avoid infanticidal males. SSI can be common in brown bear (Ursus arctos) populations and explains spatio-temporal segregation among reproductive classes. Here, we show that in a population with SSI, females with cubs-of-the-year had lower quality diets than conspecifics during the SSI high-risk period, the mating season. After the mating season, their diets were of similar quality to diets of their conspecifics. Our results suggest a nutritive risk effect of SSI, in which females with cubs-of-the-year alter their resource selection and trade optimal resources for offspring safety. Such risk effects can add to female costs of reproduction and may be widespread among species with SSI.