Annual Book of ASTM Standards, 1980. Part 31, — Water —. Philadelphia,Pa., American Society for Testing and Materials, 1980, 1404 S., $ 47.00     

R. Koch 《洁净——土壤、空气、水》1982,10(2):203-204

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Sittig,M., Pesticide Manufacturing and Toxic Materials Control Encyclopedia. Park Ridge,N. J., Noyes Data Corporation, 1980, 810 S., 96.–$     

R. Koch 《洁净——土壤、空气、水》1982,10(4):338-338

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Molekular Connectivity Indizes als strukturchemische Stoffparameter ökotoxikologischer Relevanz     

R. Koch 《洁净——土壤、空气、水》1983,11(5):511-522

The molecular connectivity index developed by Randic as a numerical expression characterizes the position and bond of atoms in the molecular structure. Since significant correlations between the molar refraction as well as electron polarizability and ecotoxicologically relevant parameters of substances were determined in the preceding investigations, such connections are investigated also for this index and sorption coefficients, bioconcentration factors and toxicity data. By the example of 56 differentiated organic substances, significant regression relations are demonstrated between bioconcentration factors, sorption coefficients and toxicity data as well as the valency molecular connectivity indices. By these regressions it is possible to determine essential distribution and action parameters of chemical substances from the structure for assesing an ecotoxicological risk. The possibilities resulting from this for predicting ecotoxicologically relevant parameters of substances are discussed.  相似文献   

Identification of regions enriched or depleted in radioelements through nondistributional analysis of aerial radiometric data     

Fredric L. Prikle  Thomas R. Bement  Jo Ann Howell  Charles D. Koch  Newton K. Stablein  Richard J. Beckman  Gary L. Tietjen 《Journal of Geochemical Exploration》1983,18(3):175-187

Throughout the aerial radiometric reconnaissance survey portion of the U.S. Department of Energy's National Uranium Resource Evaluation (NURE) program, the identification of outliers (anomalies) was an important approach to locating regions with radio-element concentrations that are either higher or lower than expected. The method introduced herein to locate such regions involves three steps: selection of a high (or low) threshold for the variate of interest; use of the sample percentile to identify all points of interest; and movement of a window over the selected data to locate significant clusters of observations. These steps, applied to aerial radiometric ²¹⁴Bi (equivalent uranium) data collected over the Copper Mountain area in Wyoming, resulted in the identification of areas enriched in that variate.  相似文献   

Certainty, uncertainty, and the spatiality of disease: a West Nile Virus example     

Tom Koch  Kenneth Denike 《Stochastic Environmental Research and Risk Assessment (SERRA)》2007,21(5):523-531

The problem is not uncertainty—proposed here as an inevitable condition—but the chimera of certainty asserted by most contemporary researchers. Problems of data definition, collection, and their use are reviewed in terms of spatial epidemiology and health data with examples drawn from several areas of contemporary health research. The argument is that preconceptions limit data modeled in a manner assuming its completeness. The result, as the West Nile Virus example seeks to demonstrate, may obscure other patterns and limit avenues of research.  相似文献   

Military Emissions, Armed Conflicts, Border Changes and the Kyoto Protocol     

Axel Michaelowa  Tobias Koch 《Climatic change》2001,50(4):383-394

The impacts of military activities in peacetime, military action and territorial changes on greenhouse gas emission commitments of nations under the Kyoto Protocol are analysed. We propose rules and institutional responsibilities to deal with the repercussions of such changes on markets in emission permits and national commitments aiming at prevention of serious distortions.  相似文献   

Zircon ages of high-grade gneisses in the Eastern Erzgebirge (Central European Variscides)—constraints on origin of the rocks and Precambrian to Ordovician magmatic events in the Variscan foldbelt     

M. Tichomirowa  H.-J. Berger  E.A. Koch  B.V. Belyatski  J. Gtze  U. Kempe  L. Nasdala  U. Schaltegger 《Lithos》2001,56(4):303-332

This study is an attempt to unravel the tectono-metamorphic history of high-grade metamorphic rocks in the Eastern Erzgebirge region. Metamorphism has strongly disturbed the primary petrological genetic characteristics of the rocks. We compare geological, geochemical, and petrological data, and zircon populations as well as isotope and geochronological data for the major gneiss units of the Eastern Erzgebirge; (1) coarse- to medium-grained “Inner Grey Gneiss”, (2) fine-grained “Outer Grey Gneiss”, and (3) “Red Gneiss”. The Inner and Outer Grey Gneiss units (MP–MT overprinted) have very similar geochemical and mineralogical compositions, but they contain different zircon populations. The Inner Grey Gneiss is found to be of primary igneous origin as documented by the presence of long-prismatic, oscillatory zoned zircons (540 Ma) and relics of granitic textures. Geochemical and isotope data classify the igneous precursor as a S-type granite. In contrast, Outer Grey Gneiss samples are free of long-prismatic zircons and contain zircons with signs of mechanical rounding through sedimentary transport. Geochemical data indicate greywackes as main previous precursor. The most euhedral zircons are zoned and document Neoproterozoic (ca. 575 Ma) source rocks eroded to form these greywackes. U–Pb-SHRIMP measurements revealed three further ancient sources, which zircons survived in both the Inner and Outer Grey Gneiss: Neoproterozoic (600–700 Ma), Paleoproterozoic (2100–2200 Ma), and Archaean (2700–2800 Ma). These results point to absence of Grenvillian type sources and derivation of the crust from the West African Craton. The granite magma of the Inner Grey Gneiss was probably derived through in situ melting of the Outer Grey Gneiss sedimentary protolith as indicated by geological relationships, similar geochemical composition, similar Nd model ages, and inherited zircon ages. Red Gneiss occurs as separate bodies within fine- and medium-grained grey gneisses of the gneiss–eclogite zone (HP–HT overprinted). In comparison to Grey Gneisses, the Red Gneiss clearly differs in geochemical composition by lower contents of refractory elements. Rocks contain long-prismatic zircons (480–500 Ma) with oscillatory zonation indicating an igneous precursor for Red Gneiss protoliths. Geochemical data display obvious characteristics of S-type granites derived through partial melting from deeper crustal source rocks. The obtained time marks of magmatic activity (ca. 575 Ma, ca. 540 Ma, ca. 500–480 Ma) of the Eastern Erzgebirge are compared with adjacent units of the Saxothuringian zone. In all these units, similar time marks and geochemical pattern of igneous rocks prove a similar tectono-metamorphic evolution during Neoproterozoic–Ordovician time.  相似文献   

Beyond light: Physical, geological, and geochemical parameters as possible submersed aquatic vegetation habitat requirements   总被引：1，自引：0，他引：1  

Evamaria W. Koch 《Estuaries and Coasts》2001,24(1):1-17

When determining the suitability of a certain area as a habitat for submersed aquatic vegetation (SAV), light and parameters that modify light (epiphytes, total suspended solids, chlorophyll concentration, nutrients) are the first factors to be taken into consideration. As a result, in the past 10 years, light has been the major focus of SAV research. Even so, we are still unable to explain why SAV often occurs in one area but is absent just a few meters away. Recent studies have shown that SAV may not occur in areas where light levels are adequate but other parameters like wave energy and sulfide concentrations are excessive. It is time to look beyond light when determining SAV habitat requirements. This paper summarizes the impact that physical (waves, currents, tides, and turbulence), geological (sediment grain size and organic matter), and geochemical (mainly sulfide) parameters may have on SAV habitat suitality. Light remains an integral part of the discussion but the focus shifts from maximum depths of distribution (determined mainly by light) to the range SAV can colonize between the maximum and minimum depths of distribution (determined mainly by physical forces). This paper establishes minimum depths of occurrence resulting from the effects of tides and waves, preferred ranges in particle size, organic content, and sulfide, as well as lilfide, as well as limits on currents and waves as related to the capacity to stay rooted at one extreme and diffusive boundary layer constrains at the other.  相似文献   

Zur Bildung von Artefakten und deren Vermeidung bei der Bestimmung leichtflüchtiger Halogenkohlenwasserstoffe in Wasser mittels Headspace-Gaschromatographie unter den Bedingungen der DIN 38407 Teil 5 (DEV-F5). Teil II: Überhöhte Trihalogenmethanbefunde in gechlortem Schwimmbeckenwasser     

J. Koch  P. Vlker 《洁净——土壤、空气、水》1996,24(4):179-184

Formation of Artefacts and its Suppression during the Determination of Volatile Halogenated Hydrocarbons in Water by Means of Headspace Gas Chromatography under the Standard Conditions of DIN 38407-F5. Part II: Increased Trihalomethane Formation in Chlorinated Swimming-pool Water A comparison of two analytical standard procedures for the determination of trihalomethanes (THM) in water (headspace gas chromatography and pentane extraction/gas chromatography) yielded strongly differing results. Under the conditions recommended by the German Standard Method DIN 38407-F5 (60…80°C for at least 60 min) degradation of thermo-labile chlorination products occurs resulting in elevated THM concentrations. The reactions involved are partly pH-dependant, and these can be suppressed by sample acidification. The degradation of trihalogen acetic acids, however, can only be influenced by minimizing the equilibration time and temperature. Other intermediate chlorination products (haloacetonitriles) are also degraded to THM after preceding hydrolysis to the corresponding carboxylic acids. Comparative results obtained with a purge and trap method at ambient temperature, i.e. without thermal stress during the enrichtment step, are lower than with static headspace GC but still high in comparison to the pentane extraction method. Presumably volatile THM-precursors are also trapped and subsequently decomposed upon thermal desorption from the trap. As the static headspace GC is the most rational method of LHKW determination available, the recommended experimental sample handling conditions should be modified in a way that deterioration reactions are reduced as far as possible.  相似文献   

Long-term variations in thermal comfort in Vienna     

E. Koch  N. Hammer  E. Rudel 《Theoretical and Applied Climatology》1992,45(4):257-264

Summary A human energy balance model is calculated using the homogeneous data set of Vienna, Austria (48°N and 16° E). Variations in the different stages of comfort since 1873 are discussed. The historical data are then used to generate scenarios of a changing climate and calculate the impact of these variations on thermal comfort.With 5 Figures  相似文献