大气有机污染分析和评价：Ⅲ.美国迈阿密市大气有机污染监测与分析   总被引：1，自引：1，他引：1  

郎庆勇 Jaffe  R 《岩矿测试》1997,16(2):118-127

自１９９４年６月至１９９５年３月对（美）迈阿密市大气颗粒物及干、湿沉降物中的多种有机化合物进行了定量分析与监测，并依据分析结果结合分子参数对有机污染水平的季节性变化、气候条件影响和清除机理等进行了探讨。  相似文献   

Factors governing the growth rate of roachRutilus rutilus (L.) in pre-alpine Lake Sarnen     

Rudolf Müller  Hans Jürg Meng 《Aquatic Sciences - Research Across Boundaries》1986,48(2):135-144

Most of the mesotrophic to eutrophic lakes in central Europe have been showing signs of oligotrophication during recent years. The question as to how the fish populations would react to this new situation was investigated looking at the growth rate of roachRutilus rutilus (L.) of Lake Sarnen, central Switzerland. The water temperature sum as day-degrees over 12 to 13°C for the months of June to October was found to be the predominant factor governing the marked year-to-year fluctuations of the growth rate. Contrary to expectation, the decreasing trophic state of the lake has not yet manifested itself noticeably in the growth rate.  相似文献   

Determination of the deformation properties of bedrock under turbine foundations     

Rudolf Hiltscher  Anders Carlsson  Tommy Olsson 《Rock Mechanics and Rock Engineering》1984,17(1):37-49

Summary This paper presents an improved investigation technique for in-situ determination of the deformation properties of rock masses, which are important parameters in the desing of foundations. This technique permits testing on a circular, one square metre area of the rock. In order to obtain reproducible loading conditions when testing, an equipment was introduced that gave almost uniformly distributed loading of the rock surface. This device is described in this paper. Displacement measurements are made in a central measuring hole, since a point of zero displacement, located equidistant between the loaded surface and the upward-pointing anchoring forces, offered a suitable reference point. In this way, the measuring device is also well protected against disturbing variations in temperature. During cyclic loading and unloading, charateristic load/deflection graphs are recorded, which directly demonstrate the deformation properties of the rock, such as the modulus of deformation at different loads, linearity deviation from linearity, as well as hysteresis effects and creep. It is clear that the results of the investigation apply only to the measuring point—the place at which the investigation was carried out. The properties of the rock nearby may vary considerably. The procedure for using this method of investigation for testing improvement measures for turbine foundations is shown in some examples.  相似文献   

Evolution of the information in the universe     

Rudolf A. Treumann 《Astrophysics and Space Science》1993,201(1):135-147

Information in the universe evolves according to a nonlinear law, which results from a combination of nonlinear dynamics and quantum theory. The Kolmogoroff-Sinai entropy rate of the Universe evolves in inverse proportion to the temperature. Since the evolution of temperature is known from standard cosmology, the time dependence of the universal entropy rate can be determined and the temporal evolution of the universal information content can be calculated. Information starts growing at the enormous rate of 10⁴⁴ bits per second from an initial value of at least 2 (seven) bits at Planck time. However, it reaches its contemporary value only if one or more inflationary phases have been passed by the Universe in the course of its evolution.  相似文献   

Determination of Antibiotic Residues in Manure,Soil, and Surface Waters     

Thorsten Christian  Rudolf J. Schneider  Harald A. Frber  Dirk Skutlarek  Michael T. Meyer  Heiner E. Goldbach 《洁净——土壤、空气、水》2003,31(1):36-44

In the last years more and more often detections of antimicrobially active compounds (“antibiotics”) in surface waters have been reported. As a possible input pathway in most cases municipal sewage has been discussed. But as an input from the realm of agriculture is conceivable as well, in this study it should be investigated if an input can occur via the pathway application of liquid manure on fields with the subsequent mechanisms surface run‐off/interflow, leaching, and drift. For this purpose a series of surface waters, soils, and liquid manures from North Rhine‐Westphalia (Northwestern Germany) were sampled and analyzed for up to 29 compounds by HPLC‐MS/MS. In each of the surface waters antibiotics could be detected. The highest concentrations were found in samples from spring (300 ng/L of erythromycin). Some of the substances detected (e.g., tylosin), as well as characteristics in the landscape suggest an input from agriculture in some particular cases. In the investigation of different liquid manure samples by a fast immunoassay method sulfadimidine could be detected in the range of 1…2 mg/kg. Soil that had been fertilized with this liquid manure showed a content of sulfadimidine extractable by accelerated solvent extraction (ASE) of 15 μg/kg dry weight even 7 months after the application. This indicates the high stability of some antibiotics in manure and soil.  相似文献   

DNA technologies for monitoring waterborne pathogens: A revolution in water pollution monitoring     

Richard Y.C. Kong  Mandy M.H. Mak  Rudolf S.S. Wu 《Ocean & Coastal Management》2009,52(7):355-358

Due to increasing population growth and anthropogenic pollution in the coastal zone, contamination of water and seafood with pathogens is probably responsible for the greatest number of human morbidities and mortalities worldwide. Hence, regular monitoring of waterborne pathogens is required to safeguard public health. Current techniques rely on the culturing of nonpathogenic indicator organisms (e.g. Escherichia coli or coliforms) for detection by inference. However, recent epidemiological evidence shows poor correlation between concentrations of E. coli/coliform and waterborne pathogens. Moreover, traditional methods are slow, not cost-effective, unable to distinguish harmful from benign strains, and fail to detect viable but nonculturable pathogens. The use of the polymerase chain reaction (PCR) has provided rapid and highly sensitive methods for the specific detection of pathogenic microorganisms. This paper briefly reviews some DNA-based technologies for waterborne pathogen detection, and describes our recent development of two new DNA-based technologies—quantitative multiplex PCR (Q-mPCR) and DNA microarray—that allow simultaneous and cost-effective detection and quantification of numerous pathogens in a single sample, which is superior to the culture methods currently in use.  相似文献   

Spin-cast ZERODUR mirror substrates of the 8 m class and lightweight substrates for secondary mirrors     

Hartmut W. Hoeness  Rudolf Mueller  Erich W. Rodeck  Friedrich B. Siebers 《Astrophysics and Space Science》1989,160(1-2):193-197

For about 20 years SCHOTT has been supplying the glass ceramic ZERODUR, a material with very low thermal expansion. Besides many other applications, ZERODUR is excellently suited for the manufacture of mirror substrates for telescopes. About 80% of all telescopes in the western world with mirror diameters >1.8 m have been equipped with ZERODUR during the last 10 years. The development of modern astronomical telescopes is aimed at larger primary mirrors and lighter secondary mirrors.New techniques have been developed by SCHOTT for manufacture of thin monolithic mirror blanks of more than 8 m in diameter. The development of thin meniscus shaped shells using the spin-casting technique was successfully completed last year. During a test production several mirror substrates up to 4.1 m in diameter and down to 57 mm in thickness could be produced. The know-how has been acquired for the fabrication of mirror substrates of more than 8 m in diameter by the spin-casting technique.SCHOTT has also performed considerable developmental work in the field of lightweighted ZERODUR mirror substrates which can be generated using different techniques: forming of the lightweighted structure during casting, fusion of individual components to a total structure and lightweighting of a massive block by various mechanical machining methods.Paper presented at the Symposium on the JNLT and Related Engineering Developments, Tokyo, November 29–December 2, 1988.Registered trademark of SCHOTT Glaswerke, Mainz.  相似文献   

Temporary collapse of the <Emphasis Type="Italic">Daphnia</Emphasis> population in turbid and ultra-oligotrophic Lake Brienz   总被引：2，自引：0，他引：2  

Christian Rellstab  Vinzenz Maurer  Markus Zeh  Hans Rudolf Bürgi  Piet Spaak 《Aquatic Sciences - Research Across Boundaries》2007,69(2):257-270

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Comparative effects of the blue green algae Nodularia spumigena and a lysed extract on detoxification and antioxidant enzymes in the green lipped mussel (Perna viridis)     

Davies WR  Siu WH  Jack RW  Wu RS  Lam PK  Nugegoda D 《Marine pollution bulletin》2005,51(8-12):1026-1033

Nodularia spumigena periodically proliferates to cause toxic algal blooms with some aquatic animals enduring and consuming high densities of the blue green algae or toxic lysis. N. spumigena contains toxic compounds such as nodularin and lipopolysaccharides. This current work investigates physiological effects of exposure from bloom conditions of N. spumigena cells and a post-bloom lysis. Biochemical and antioxidative biomarkers were comparatively studied over an acute 3-day exposure. In general, a post-bloom N. spumigena lysis caused opposite physiological responses to bloom densities of N. spumigena. Specifically, increases in glutathione (GSH) and glutathione peroxidase (GPx) and decreases in glutathione S-transferase (GST) were observed from the N. spumigena lysis. In contrast, N. spumigena cell densities decreased GSH and increased GST and lipid peroxidation (LPO) in mussels. Findings also suggest that at different stages of a toxic bloom, exposure may result in toxic stress to specific organs in the mussel.  相似文献   

Contents of Volume 48     

Rudolf BráZdil  Christian Pfister  Heinz Wanner  Hans Von Storch  JüRg Luterbacher 《Climatic change》2001,48(4):653-655

Volume Contents

Contents of Volume 48  相似文献