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Christian Junge 《Die Naturwissenschaften》1981,68(5):236-244
The formation of the atmosphere-together with that of the oceans and sediments-was determined by three important processes: the loss of noble gases and volatiles in the solar nebula, the enrichment of these substances at the Earth's surface by exhalation from the Earth's mantle, and finally the formation of the hydrosphere, enabled by-in contrast to our neighboring planets-a suitable distance from the sun. In this way the development of the atmospheric gases N2, H2O and CO2 was largely fixed. Oxygen, on the other hand, appeared late in the atmosphere. It originated from biological photosynthesis which apparently developed rather early in the Earth's history but lead at first only to oxidation of iron and sulfur. The subsequently occurring accumulation of free oxygen in the atmosphere resulted in interesting interrelations with the development of life. 相似文献
434.
Nonylphenols and nonylphenolethoxylates with one, two, and three oxyethylene groups were identified in effluents from activated sludge sewage treatment plants. The complex mixtures of isomers are considered to be refractory metabolites of nonionic detergents. 相似文献
435.
Heavy metals in seaducks and mussels from misty fjords national monument in Southeast Alaska 总被引:2,自引:0,他引:2
J. Christian Franson Philip S. Koehl Dirk V. Derksen Thomas C. Rothe Christine M. Bunck John F. Moore 《Environmental monitoring and assessment》1995,36(2):149-167
Quartz Hill, in Misty Fjords National Monument near Ketchikan, Alaska, is the site of a proposed molybdenum-producing mine. To provide baseline data for use in post-development comparisons, we analyzed tissues of Barrow's goldeneyes (Bucephala islandica), common mergansers (Mergus merganser), and blue mussels (Mytilus edulis) for seven heavy metals that could potentially be released into the environment as a result of mining operations. Specimens were collected in 1980, 1981, and 1982 from two fjords likely to be used for discharge of tailings from the proposed mine and from two control fjords. Concentrations of arsenic, cadmium, copper, chromium, molybdenum, lead, and zinc were measured in soft tissues of mussels and in kidney, liver, and muscle of birds. The highest mean concentrations of metals found in bird tissues were 55.7 ppm dry weight cadmium in kidneys and 154 ppm dry weight zinc in livers of Barrow's goldeneyes. Concentrations of several metals in blue mussels differed among seasons and locations, but the most significant finding in mussels was a maximum mean cadmium concentration of 9.6 ppm dry weight, a level higher than normally found in undisturbed areas. With the exception of 104 ppm dry weight cadmium in the kidney of one common merganser and 12.7 ppm dry weight lead in the kidney of another, concentrations of other metals in seaduck and mussel tissues were low, consistent with what would be expected for a pre-development environment. Molybdenum was found in low concentrations (<10 ppm dry weight) in all avian kidney samples and most liver samples, but was not detected in blue mussels.THE U.S. GOVERNMENT RIGHT TO RETAIN A NON-EXCLUSIVE, ROYALTY FREE LICENCE IN AND TO ANY COPYRIGHT IS ACKNOWLEDGED. 相似文献
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Summary The conventional economic accounting systems have not played an enlightening role in statistically revealing the actual damage to the environment. They can, however, be methodologically improved; and they must be complemented by assessments of the ecological costs of the production process.In this article statistical evidence is provided on the level and structure of environmental damage and protection expenditures in the Federal Republic of Germany,i.e. on the environmental damage itself and on the environmental protection investments by industry and government, the capital stock for environmental protection, the total costs of and expenditures for environmental protection.Dr Christian Leipert and Prof. Udo Simonis are both regular contributors toThe Environmentalist (see 1989, pp.171–183; 1990, pp.25–38). Prof. Simonis is Director of the International Institute for Environment and Society (Wissenschaftszentrum) and Dr Leipert a member of its research staff. 相似文献
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Schlick-Steiner BC Steiner FM Höttinger H Nikiforov A Mistrik R Schafellner C Baier P Christian E 《Die Naturwissenschaften》2004,91(5):209-214
Deception is a crucial yet incompletely understood strategy of social parasites. In central Europe, the Mountain Alcon Blue, Maculinea rebeli, a highly endangered butterfly, parasitises several Myrmica ant species. Caterpillars gain access to host nests probably by faking the ants odour. We analysed gas chromatography–mass spectrometry data of body surface hydrocarbons of pre-adoption and hibernated larvae of Maculinea rebeli and of their host species Myrmica sabuleti and M. schencki. Data were ordinated by different methods, based on similarities in the relative quantities of compounds between chromatograms. The two Myrmica species exhibit species-specific profiles. The Maculinea rebeli pre-adoption larva has a complex profile that simultaneously contains species-specific substances of the two investigated host species. This evidence leads to the interpretation that, in central Europe, Maculinea rebeli is predisposed for multi-host use by the chemical signature of its pre-adoption larva. The Maculinea rebeli larva clearly does not rely on an intersection-odour of compounds common to all host ant species, but synthesises an aggregate-odour containing specific compounds of each of the investigated hosts. We term this previously unknown chemical strategy aggregate-odour multi-host mimicry.B.C. Schlick-Steiner and F.M. Steiner contributed equally to this work. 相似文献
439.
Heavy bombing during World War II in Europe, particularly in Germany, left thousands of unexploded bombs buried underground and underwater. The bombs can be detected with magnetic sensors, but sorting through the huge amounts of data generated in area searches has proven to be by far the most difficult part of the task. Recently, a data analysis program has been developed that is capable of correlating global positioning system (GPS) data to magnetic sensor readings to identify likely bomb site candidates in a remarkably short period of time. A key to the success of this application is the use of packaged data-analysis software, Origin, from Microcal Software, Inc. (Northampton, Massachusetts), which is capable of interfacing to external C and C++ pattern curve-fitting routines that operate at the required high rates of speed. 相似文献
440.