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251.
Gabi Förtsch Helmut Krinn Gabi Mai Heinz Meinholz Michael Pleikies 《Environmental Sciences Europe》1996,8(5):293-299
Economic regulations on recycling and respective waste disposal legislation will increasingly demand the realization of new waste management concepts. They do not stem from a ministerial goal in itself, but instead offen the enterprizes a chance to develop their own waste disposal strategies with a goal toward the future. In the course of an Intra-company analysis, this waste disposal concept must take the operative organization, the relevant processes and manufacturing techniques, the accumulation of waste in the cost centers as well as the waste disposal and utilization into consideration. Fundamental principles include the environmental regulations applicable to the enterprize in the form of both federal decress and injunctions. An environmental examination report demonstrates the methodical possiblities for stock-taking and makes it possible to identify the measures necessary for improving the operational waste disposal situation. The mandatory data acquisition and a feasible waste monitoring network can be used in the course of environmental management system for making an expert opinion by an independent, reputable environmental verifier. 相似文献
252.
The Science of Nature - 相似文献
253.
Animal Meal: Production and Determination in Feedstuffs and the Origin of Bovine Spongiform Encephalopathy 总被引:1,自引:0,他引:1
Hahn H 《Die Naturwissenschaften》1999,86(2):62-70
This contribution examines what animal meal is, how it is produced in rendering plants, and means of investigating feedstuff constituents. In addition to animal meal, numerous other products of animal origin are also on the market (e.g., blood meal, bone meal, feather meal, gelatin). Constituents of animal origin can be detected in feedstuffs by microscopy, but determining the animal species from which the constituents are derived, as required by law in Germany, requires methods such as enzyme-linked immunosorbent assay and polymerase chain reaction. We consider the problem of trace contamination being introduced accidentally during the production of ruminants feedstuffs containing constituents of animal origin. The future of animal meal is discussed together with alternatives for disposing of animal carcasses and slaughtery offal, i.e., composting and incineration. 相似文献
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The Science of Nature - 相似文献
258.
Untersuchungen zum Vorkommen polycyclischer Moschus-Duftstoffe in verschiedenen Umweltkompartimenten
Hans -Dietrich Eschke Josef Traud Heinz -Jürgen Dibowski 《Environmental Sciences Europe》1994,6(4):183-189
New flavors have been detected in GC/MS chromatograms of surface and sewage waters and fish analyzed for nitro musk compounds. This article names the polycyclic musk flavors 1,3,4,6,7,8-hexahydro-4, 6,6,7,8,8-hexamethylcyclopenta-(g)-2-benzopyrane (HHCB, known for instance under the trade names: Galaxolide® and Abbalide®), 7-acetyl-1,1,3,4,4,6-hexamethyltetralin (AHTN, known for instance under the trade names: Tonalide® and Fixolide®) and 4-Acetyl-1,1-dimethyl-6-tert.butylindane (ADBI, known for instance under the trade names: Celestolide® and Crysolide®). These substances, which are widely used in the cosmetics and flavor industries, here have been established for the first time in the aquatic environment. HHCB, AHTN and ADBI — as relatively non-polar lipophilic chemicals — like organochlorine pesticides and PCBs after extraction and consecutive purification by gel permeation and silicagel adsorption chromatography are accessible to analysis by gas chromatography/mass spectrometry. Mass spectra show typical mass fragments which allow an unambigous identification and quantification. First results for surface and sewage waters and fish underline the persistence and a relatively high bioconcentration potential of these substances and suggest their ubiqitious distribution in the aquatic environment. 相似文献
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Christopher R. Ellis Heinz G. Stefan 《Journal of the American Water Resources Association》1991,27(6):903-914
ABSTRACT: Artificial aeration is used to prevent winter fish kills due to oxygen depletion in ice-covered lakes. Conventional aeration by air bubble plumes and other techniques usually mixes the water column and produces hazardous open water in the ice cover. A non-mixing winter lake aeration system which creates a fish refuge was designed and field tested to oxygenate the water and maintain water temperature stratification in a lake such that no open water is created. The system uses a cascade aerator and has a design discharge and dissolved oxygen input rate of 85 1/s and 70 kg/d, respectively. Aerated water is discharged near mid-depth with minimum disturbance of the ambient water through a specially designed diffuser. The system was tested in a shallow 3 m deep lake of 17 ha surface area during two winters and was found to perform as expected. Significant photosynthetic production of dissolved oxygen under the ice-cover was also observed during snow-free periods. 相似文献