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91.
Oliver Schwab Helmut Rechberger Robert Holnsteiner 《?sterreichische Wasser- und Abfallwirtschaft》2016,68(9-10):435-442
The influence of anthropogenic processes on global material flow systems increasingly dominates the influence of natural processes. In this context, the provision of detailed knowledge on material flow systems is relevant for decision makers in resource policy. This information can be provided in the form of one-year material balances or, if repeated over a period of consecutive years, in the form of national resource budgets. In national resource budgets, all relevant flows of a material through a national economy are balanced and displayed in neatly arranged diagrams. By updating these material balances over a series of years, the development of material stocks can be estimated. Upcoming challenges both regarding supply and disposal of materials can be identified. Comprehensive balances are useful for decision makers in resource policy and, moreover, as an information basis for future exploitation of anthropogenic resources. However, both availability of data and possibilities for assessing the reliability of data are very limited. In this work, a methodology for investigating and evaluating the information basis of national resource budgets is presented. The methodology includes procedures for systematic characterization of resource budget data and formal procedures for evaluating their reliability. From a scientific perspective, the methodology contributes to understanding material flow systems better. It also enables implementing procedures towards national resource budgets in an administrative context. 相似文献
92.
Therese Schwarzböck Helmut Rechberger Oliver Cencic Johann Fellner 《?sterreichische Wasser- und Abfallwirtschaft》2016,68(9-10):415-427
Since combustible wastes usually consist of biogenic (e.g. paper, wood, food waste) and fossil organic matter (plastics), their thermal recovery results in climate neutral and climate relevant CO2 emissions. Moreover, the fraction of biogenic materials in the waste feed is relevant for the amount of renewable energy produced. The latter has to be reported and might be subsidized according to national laws (e.g. based on European directive 2009/28/EG). The present study represents the first comprehensive evaluation of the share of biogenic and fossil materials in the waste feed of waste-to-energy (WTE) plants on a national basis. The Balance Method, which is patented on a European level by TU Wien, was applied to 10 out of 13 Austrian WTE plants (around 2.3 Mio tons of waste corresponding to around 88 % of the overall waste feed in Austrian WTE plants). The method is based on the mathematical reconciliation of the material properties (e.g. mean chemical composition of biogenic and fossil materials) and routinely recorded operating data of WTE plants (e.g. flue gas volume, CO2 and O2-content in the dry flue gas, steam production). The results demonstrate large variations for the share of energy from biogenic sources in the different WTE plants, ranging from 35.7 ± 2.4 % to 61.2 ± 2.7 % (based on annual averages). Additionally, for several WTE plants large temporal variations can be observed based on monthly mean values. Thus, a plant-specific and continuous evaluation of the waste composition in WTE plants (which the Balance Method allows to do at reasonable efforts) can be recommended for a reliable reporting of the renewable share of energy or fossil CO2 emissions from waste incineration. The energy input which stems from fossil and biogenic sources can be estimated to 11,450 ± 120 TJ and 10,730 ± 110 TJ, respectively for the year 2014 (for the 10 WTE plants). In total 1060 ± 24 kt fossil CO2 emissions from the thermal recovery of waste in Austria’s WTE plants in 2014 could be determined (estimation for all 13 WTE plants). 相似文献
93.
Helmut Brandl Claudia Fricker-Feer Dominik Ziegler Jyotshna Mandal Roger Stephan Angelika Lehner 《Journal of dairy science》2014
Airborne communities (mainly bacteria) were sampled and characterized (concentration levels and diversity) at 1 outdoor and 6 indoor sites within a Swiss dairy production facility. Air samples were collected on 2 sampling dates in different seasons, one in February and one in July 2012 using impaction bioaerosol samplers. After cultivation, isolates were identified by mass spectrometry (matrix-assisted laser desorption/ionization-time-of-flight) and molecular (sequencing of 16S rRNA and rpoB genes) methods. In general, total airborne particle loads and total bacterial counts were higher in winter than in summer, but remained constant within each indoor sampling site at both sampling times (February and July). Bacterial numbers were generally very low (<100 cfu/m3 of air) during the different steps of milk powder production. Elevated bacterial concentrations (with mean values of 391 ± 142 and 179 ± 33 cfu/m3 of air during winter and summer sampling, respectively; n = 15) occurred mainly in the “logistics area,” where products in closed tins are packed in secondary packaging material and prepared for shipping. However, total bacterial counts at the outdoor site varied, with a 5- to 6-fold higher concentration observed in winter compared with summer. Twenty-five gram-positive and gram-negative genera were identified as part of the airborne microflora, with Bacillus and Staphylococcus being the most frequent genera identified. Overall, the culturable microflora community showed a composition typical and representative for the specific location. Bacterial counts were highly correlated with total airborne particles in the size range 1 to 5 µm, indicating that a simple surveillance system based upon counting of airborne particles could be implemented. The data generated in this study could be used to evaluate the effectiveness of the dairy plant’s sanitation program and to identify potential sources of airborne contamination, resulting in increased food safety. 相似文献
94.
Dipl.-Ing. Thomas Klein Salar Niknafs Rian Dippenaar Helmut Clemens Svea Mayer 《BHM Berg- und Hüttenm?nnische Monatshefte》2014,159(7):289-290
Solid-state phase transformations and grain growth of an intermetallic γ-TiAl alloy were investigated in-situ using high-temperature laser scanning confocal microscopy (HTLSCM). During isothermal annealing in the single β-phase region, significant grain coarsening was observed. On cooling beneath the β-transus temperature with different rates, a CCT diagram was evaluated for the initiation of β to α phase transformation and changes in the morphology were observed. 相似文献
95.
Dipl.-Ing. Dr. mont Alfred Maier Peter Moser Wilfried Eichlseder Martha Mühlburger Katrin Brugger Helmut Antrekowitsch Manfred Hoscher 《BHM Berg- und Hüttenm?nnische Monatshefte》2014,159(4):143-148
The European Initiatives manifested in the Communications of the European Commission on Raw Materials, in the Strategic Implementation Plan of the European Innovation Partnership on Raw Materials and in the 2014 Call of the European Institute for Innovation & Technology (EIT) for a Knowledge and Innovation Community (KIC) on Raw Materials lead to manifold Austrian activities on Government level and on level of the Montanuniversitaet Leoben. The ESEE Region, thus East- and Southeast Europe has a special role. 相似文献
96.
97.
Alkylation of N‐vinylpyrrolidone using lithium diisopropylamide and bis(2‐bromoethyl) ether was carried out to obtain 3‐(2‐(2‐bromoethoxy)ethyl)‐1‐vinyl‐2‐pyrrolidone ( 2 ). The derivative 2 represents a versatile starting molecule for further modification via nucleophilic displacement yielding, for example, the bicyclic 2‐vinyl‐8‐oxa‐2‐azaspiro[4.5]decan‐1‐one ( 4 ) or the ammonium salt 3‐diethoxy‐N,N′‐((dimethylbenzyl)ammonium bromide)‐1‐vinyl‐2‐pyrrolidone ( 10 ). Via free radical polymerization of 4 and 10 , the corresponding homopolymers were obtained. Copolymerization of 4 and 10 with N,N′‐diethylacrylamide yielded water‐soluble materials. The thermosensitive solubility of copolymers poly[(2‐vinyl‐8‐oxa‐2‐azaspiro[4.5]decan‐1‐one)‐co‐(N,N′‐diethylacrylamide)] and poly[(3‐diethoxy‐N,N′‐((dimethylbenzyl)ammonium bromide)‐1‐vinyl‐2‐pyrrolidone)‐co‐(N‐vinylpyrrolidone)] in water was investigated. © 2015 Society of Chemical Industry 相似文献
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