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301.
Friedrich von Huene 《International Journal of Earth Sciences》1929,20(2):81-96
Zusammenfassung In der im vorhergehenden auseinandergesetzten Weise glaubt Verf. die Hypothese eines bis Südamerika von Osten her reichenden Gondwanalandes durch eine annehmbarere ersetzt zu haben. Die hier aufgestellte Annahme einer Verbindung Südamerikas mit SO-Asien durch die australische Region erklärt nicht nur die auffallenden Verhältnisse der Landfaunen, sondern ist auch durch eine große Menge von geologischen Ereignissen und Zuständen gestützt, die nicht Hypothesen, sondern Tatsachen sind. Am Schluß des Paläozoikums ist der hier nicht genauer aufgeführte Parallelismus der geologischen Geschehnisse in Südafrika und in Südamerika ein auffallender, er reicht auch noch ins Mesozoikum hinein. Faunistische Beziehungen sind durch die Mesosaurier unleugbar gegeben, aber im Mesozoikum fehlen sie schon fast ganz. Im Laufe des Mesozoikums tritt ein ebenso starker Parallelismus des geologischen Geschehens zwischen Australasien und Südamerika ein. Aber die Erforschung der Lebewelt sowohl Südamerikas in vergangener Zeit als auch Australasiens besonders muß noch große Fortschritte machen, bis ein volles Bild dieser Vorgänge vor uns liegt; bis jetzt besteht es fast nur aus einer Reihe von Lücken. Diese Zeilen wollen neue Arbeit wecken, die Kenntnis zu erhöhen. 相似文献
302.
303.
Clemens Reimann Arnold Arnoldussen Peter Englmaier Peter Filzmoser Tor Erik Finne Robert G. Garrett Friedrich Koller Øystein Nordgulen 《Applied Geochemistry》2007
Rock samples and the C-, B- and O-horizons of soils developed on these rocks were collected in forested areas along a 120-km south–north transect in southern Norway, passing through the city of Oslo. Forty samples (1 site/3 km) were analysed for 37 chemical elements (Ag, Al, As, Au, B, Ba, Bi, Ca, Cd, Co, Cr, Cu, Fe, Ga, Hg, K, La, Mg, Mn, Mo, Na, Ni, P, Pb, S, Sb, Sc, Se, Sr, Te, Th, Ti, Tl, U, V, W and Zn) following an aqua regia digestion; pH (water extract) and loss on ignition were also determined. The O-horizon soils were additionally analysed for Pt. Gold is the only element that shows a clear anthropogenic peak in the O-horizon soils collected from the city of Oslo. Silver, Au, Bi, Cd, Hg, Pb, S, Sb, Se and Sr all show a strong enrichment in the O-horizon when compared to the underlying C-horizon or the bedrock along the full length of the transect. Neither geology nor anthropogenic input of elements dominate the observed patterns. The most important factors for the observed element concentrations in the O-horizon are weathering, uptake (or rejection) of elements by plants and the kinetics of decay of the organic material in the O-horizon. Climate, especially temperature and precipitation, has an important influence on the formation and decay rates of the organic soil layer. Acid precipitation will delay the decomposition of the organic layer and lead to a natural enrichment of several metals in the O-horizon. Land use change, deforestation and liming can all increase the decay kinetics of organic matter and thus result in a release of the stored element pool. 相似文献
304.
Another Revision of the Saprobic Index ‐ Why and What For? The 1990 revision of the German standard DIN 38410 “Determination of the Saprobic Index in Running Waters” had to be revised again in the course of a periodical updating due to the DIN regulations. Thus, practical experience can be taken into account as well as scientific development and the legal requirements. In this work, modifications of the standard are explained as far as it is not done within DIN 38410. Additionally, emerged suggestions and critiques are discussed. The necessity of quality assurance is especially emphasized. An essential part of the revision is the considerable enlargement of the list of indicators (macro‐ and microorganisms). Beside this, type‐specific ranges of the saprobic index are presented for the reference status in all types of German rivers. Consequently the saprobic system may be used as a metric for the biological assessment with the benthic fauna within the implementation of the European Water Framework Directive. Moreover, many details of the standard have been tightened up. The methods for further enlargements of these lists will also be described, especially the proceeding for the inclusion of neozoic organisms as indicators within the saprobic system. A formula concerning the statistical securing of the saprobic index is not given anymore, mainly because of the high variability of habitats and biocoenses in pristine environments. Further information for quality assurance is given as well. 相似文献
305.
F. Slemr G. Baumbach P. Blank U. Corsmeier F. Fiedler R. Friedrich M. Habram N. Kalthoff D. Klemp J. Kühlwein K. Mannschreck M. Möllmann-Coers K. Nester H.-J. Panitz P. Rabl J. Slemr U. Vogt B. Wickert 《Journal of Atmospheric Chemistry》2002,42(1):207-233
Emission inventories of NOx, CO, and individual volatile organic compounds (VOC), highly resolved in space and time, belong to the most important input parameters for chemistry and transport models (CTM) used for ozone prediction. Because of the decisive influence of the input quality on the outcome of CTM simulations, the quality of emission inventories has to be assessed. This paper presents an experimental evaluation of the highly resolved emission inventories for the city of Augsburg. The emissions of the city, determined in March and October 1998 using mass balance and tracer techniques, and derived from the measured receptor concentration ratios, were compared with emissions modeled from an emission inventory. The modeled CO emissions were in agreement with the measured ones within the combined experimental and model uncertainties. More detailed CO emission model simulations suggest that the tendency of calculated CO emissions being smaller than the measured ones may be due to higher traffic activity in Augsburg. Modeled NOx emissions were in agreement with the measured ones within the combined experimental and model uncertainties. Large deviations between modeled and measured values have been found for some individual NMHC compounds. The measured NMHC emission fingerprints were dominated by mobile sources. Substantial model predicted NMHC emissions from the solvent use could not be detected by measurements suggesting that they may not be correctly represented by the emission model. 相似文献
306.
307.
Friedrich Volz 《Pure and Applied Geophysics》1965,60(1):197-200
Summary Highest values of measured sky polarization 90° from the sun as function of solar elevation have been compared with theoretical data of the Rayleigh atmosphere for different albedo. The conclusion is that the effective albedo of the earth surface increasing from 0.1 at 40° solar elevation to about 0.25 at 10° elevation, whereas reflection according Lamberts cosine law would result in an albedo independent of solar elevation. This result could be generally confirmed by laboratory measurements of albedo of surfaces like grass, soil, sand, etc.
Publication No. 82. 相似文献
Zusammenfassung Höchste gemessene Werte der Himmelslichtpolarisation in 90° Abstand von der Sonne in Abhängigkeit von der Sonnenhöhe wurden mit theoretischen Werten der Polarisation einer Rayleigh-Atmosphäre bei verschiedener Albedo verglichen. Es ergibt sich daraus, dass die effektive Albedo der Erdoberfläche von etwa 0.1 bei 40° Sonnenhöhe auf 0.25 bei 10° Sonnenhöhe ansteigt, während Reflektion nach dem Lambertschen cos-Gesetz eine Albedo bedingen würde, die unabhängig von der Sonnenhöhe ist. Dieses Ergebnis konnte durch Labormessungen der Albedo in Abhängigkeit vom Einfallswinkel für Oberflächen aus Gras, Boden, Sand und anderem im wesentlichen bestätigt werden.
Publication No. 82. 相似文献
308.
57Fe Mössbauer spectra of natural glasses (pumices and obsidians) and of synthetic glasses of granitic composition have been analyzed. — Ferric iron is found in tetrahedral coordination if enough M+-cations are available to balance the charge of both M+Fe3+O2 and M+AlO2 complexes. In other compositions the ratio of tetrahedrally to octahedrally coordinated Fe3+ depends on the ratio of mono-to divalent cations. — Ferrous iron occurs in two distinctly different octahedral sites. The existence of these sites can be attributed to different anionic units adjacent to Fe2+. The degree of polymerization of these units is reflected in the quadrupole splitting. The anionic units adjacent to Fe2+ are depolymerized for increasing mean Z/r
2 of the network modifiers, which do not stabilize M3+ in the tetrahedra by local charge balance. — Increasing pressure diminishes the geometric differences between these types of ferrous iron-oxygen-octahedra, which gives rise to a more even distribution of Fe2+ among these sites and thereby to an ordering in the network of melts. 相似文献
309.
310.
Hydrothermal syntheses were made mainly in the binary system SiO2-H2O in a temperature range between 300 ° C and 500 ° C and pressures from 0.2 kbar up to 4.0 kbar with various starting materials. In this way the transformation behavior of different amorphous silicas via cristobalite and keatite to quartz were observed. This behavior depends mainly on the parameters: pressure, temperature, run duration and state of the starting material. Four reaction paths have been observed: in most experiments the complete reaction sequence “amorphous silica→cristobalite→keatite→quartz” took place. Less often the reactions: “amorphous silica→cristobalite→quartz” and: “amorphous silica→keatite→quarts” were observed. Very few samples were found with a direct transition of amorphous silica into quartz at high pressures. A kinetic model is given in form of a pressure-temperature-time diagram of the system SiO2-H2O under hydrothermal conditions. 相似文献