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1.
The Mangshan Plateau is located on the south bank of the Huang He (Yellow River) just west of the city of Zhengzhou, well outside the Loess Plateau in central China. Mixing models of the grain‐size data indicate that the loess deposits are mixtures of three loess components. Comparison of the mixing model with existing models established for a series of loess–palaeosol sequences from the Loess Plateau indicates that the Mangshan loess has been supplied from a proximal dust source, the Huang He floodplain, during major dust outbreaks. The high accumulation rates, the composition of the loess components, and especially the high proportions of a sandy loess component support this. Owing to the exceptionally high accumulation rates, the Mangshan grain size, magnetic susceptibility and carbonate records provide a high‐resolution archive of environmental and climate change. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
2.
This paper provides an historical perspective on micrometeorological field experiments designed to evaluate air-sea interaction processes. Of course, marine meteorology is much older, and air-sea interaction has always been an inevitable part of it. But only in this century have the tools been developed to go from qualitative understanding towards quantitative measurements of interactions.  相似文献   
3.
The Hii regions S254, 255 and 257 in the constellation of Orion are close together on the sky and appear like a triple object. Fabry-Pérot radial velocities of the Hii regions as well asUBV photo-electric magnitudes of their exciting stars are obtained. The data show that (1) all three nebulae are at a distance of 2.5 kpc; (2) an excess extinction is observed in S255 and S257 while S254 shows no excess extinction; (3) S255, identified as an IR and a molecular source, is the youngest object of the group. It is concluded that the three Hii regions are at different evolutionary stages.  相似文献   
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The effect of spray droplets in the marine surface layer on evaporation is considered. Independent evidence from energy constraints, from visibility and from sea salt content of air is used. The estimation shows that, except perhaps for hurricane wind strength, the increase of total evaporation from evaporating droplets is negligible. This is in agreement with recent experimental evidence.  相似文献   
6.
Measurement and interpretation of mass fluxes in favor of concentrations is gaining more and more interest, especially within the framework of the characterization and management of large-scale volatile organic carbon (VOC) groundwater contamination (source zones and plumes). Traditional methods of estimating contaminant fluxes and discharges involve individual measurements/calculations of the Darcy water flux and the contaminant concentrations. However, taken into account the spatially and temporally varying hydrologic conditions in complex, heterogeneous aquifers, higher uncertainty arises from such indirect estimation of contaminant fluxes. Therefore, the potential use of passive sampling devices for the direct measurement of groundwater-related VOC mass fluxes is examined. A review of current passive samplers for the measurement of organic contaminants in water yielded the selection of 18 samplers that were screened for a number of criteria. These criteria are related to the possible application of the sampler for the measurement of VOC mass fluxes in groundwater. This screening study indicates that direct measurement of VOC mass fluxes in groundwater is possible with very few passive samplers. Currently, the passive flux meter (PFM) is the only passive sampler which has proven to effectively measure mass fluxes in near source groundwater. A passive sampler for mass flux measurement in plume zones with regard to long-term monitoring (several months to a year) still needs to be developed or optimized. A passive sampler for long-term monitoring of contaminant mass fluxes in groundwater would be of considerable value in the development of risk-based assessment and management of soil and groundwater pollutions.  相似文献   
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Zusammenfassung Für ein in der Abhandlung von K. Brocks [1955] abgeleitetes Verfahren der Berechnung von Brechungsindex-Profilen unmittelbar über dem Meer werden weitere Hilfsmittel angegeben, insbesondere eine graphische Psychrometertafel (Tafel 8), aus der der Dampfdruck der Luft [in mb] als Funktion der Temperatur des feuchten und trockenen Thermometers entnommen werden kann, und ein Diagramm des Wasserdampfdrucks und des Sättigungsdampfdruckes der Luft sowie der relativen Luftfeuchtigkeit als Funktion der Lufttemperatur (Tafel 9).Es wird ferner ein Kurzverfahren mitgeteilt, das eine schnelle Berechnung des Brechungsindexprofils über dem Meer ermöglicht aus Messungen der Lufttemperatur, Luftfeuchtigkeit, Windgeschwindigkeit und Wassertemperatur. Hierfür wird ein Diagramm gegeben (Tafel 10), das den BrechungswertN=(n–1) 10–6 als Funktion der Temperatur des trockenen und des feuchten Thermometers bzw. der Wassertemperatur enthält.
On the gradient of the refractive index of electro-magnetic waves (centimetre-to metre-waves) in the maritime boundary layer of the atmosphere. 2nd article
Summary The present paper adds further aids to the method developed by K. Brocks [1955] for the computation of the curves of the refractive index occurring immediately above the sea surface. These aids, before all, consist in a graphical psychrometer plate (plate 8) and a diagramme (plate 9). Plate 8 permits to derive from it the vapour pressure of the air [in mb] as a function of temperature to be read from dry bulb and a wet bulb thermometres. Plate 9 represents the water vapour pressure and the saturation pressure of the air as well as relative humidity of the air as a function of air temperature.Besides, an abbreviated method is discussed permitting a time-saving computation of the curves of the refractive index above sea surface from measurements of air temperature, atmospheric moisture, wind velocity, and water temperature. This computation is carried out with the aid of a diagram (plate 10), giving the refractive valueN=(n–1) 10–6 as a function of the temperature, measured with a dry bulb and a wet bulb thermometre, or as a function of the water temperature, respectively.

Sur le gradient de l'indice de réfraction des ondes électromagnétiques (de 0,1 m à 1m), présentes dans la couche limite maritime de l'atmosphère. 2e article
Résumé Le travail actuel ajoute à la méthode développée par K. Brocks [1955] d'autres moyens pour le calcul des courbures du gradient de l'indice de réfraction se présentant immédiatement au-dessus de la surface de la mer. Ces moyens se composent surtout d'une représentation graphique des valeurs psychométriques (planche 8) et d'un diagramme (planche 9). La planche 8 permet d'en tirer la pression de vapeur de l'air [en mb] en fonction de températures indiquées sur de thermomètres mouillés ou sur de thermomètres secs. La planche 9 montre la pression de vapeur d'eau et la tension de vapeur saturante de l'air ainsi que l'humidité relative de l'air en fonction de la température de l'air.De plus, une méthode abbréviée est présentée qui permet de calculer, sans perdre beaucoup de temps, au moyen des mesures de la température de l'air et de l'eau, de l'humidité de l'air et de la vitesse du vent, la courbure de l'indice de réfraction au-dessus de la mer. Ce calcul se fait à l'aide d'un diagramme (planche 10) qui donne la valeur de réfractionN=(n}-1) 10–6 en fonction de la température du thermomètre sec et du thermomètre mouillé ou la représente respectivement en fonction de la température de l'eau.
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9.
The vertical turbulent fluxes have been determined during the Atlantic Trade Wind Experiment (ATEX) both by direct and profile methods. The drag coefficient obtained from direct measurements was c D = 1.39 × 10–3. A distortion of the wind profile due to wave action could be demonstrated, this produced an increased drag coefficient estimated by the profile method. The dissipation technique using the downwind spectrum gave a lower drag coefficient of 1.26 × 10–3, probably due to non-isotropic conditions (the ratio of vertical to downwind spectrum at high frequencies scattered considerably with an average of 1 instead of 4/3).From direct measurements, the sensible heat flux showed a poor correlation with the bulk parameter product U, contrary to the heat flux obtained from profiles. It is shown that this is due to the higher frequency part of the cospectrum, say above 0.25 Hz, which contributes more than 50 % of the total flux. Determination of the heat flux from temperature fluctuations by the dissipation method would be in agreement with the direct determination only if the corresponding Kolmogoroff constant were 2.1 instead of 0.8.For the vertical flux of water vapor obtained from profiles, the bulk transfer coefficient was 1.28 × 10–3.This work was supported by the Deutsche Forschungsgemeinschaft, Schwerpunktprogramm Meeresforschung and later the Sonderforschungsbereich Meeresforschung Hamburg.  相似文献   
10.
Hermann Abich was born in 1806 in Berlin and died in 1886 in Graz. He grew up in a wealthy family which had friendly relations with famous scientists like Alexander von Humboldt, Leopold von Buch or Carl Ritter. After his studies in Heidelberg and Berlin he turned to extended fieldwork at the volcanoes of Italy. In 1833–1834 he published excellent petrological/chemical results and got soon a good scientific reputation. Thus he was nominated as Professor for Geology and Mineralogy of the prestigious Russian University in Dorpat (now Tartu, Esthonia) in 1842. In 1844 he was sent to Armenia by the Russian authorities. For the next three decades his fieldwork with about 190 publications was concentrated on the Great and Lesser Caucasus. This was a period of Russian expansion to the South with long-lasting regional fights. But he enjoyed the support of powerful governors. He was an indefatigable and enthusiastic explorer and a precise observer and designer. His interests covered many fields: morphology, glaciology, structural geology, volcanology with Thermal Springs, mineral resources from hydrocarbons, coal, salt to ores, stratigraphy and paleontology as a base for geological maps. But he also gave advice for practical problems, and he was active in meteorology, botany and archaeology. Alltogether he became “the Father of Caucasus Geology”. The following sketch stresses only on three aspects of his activities. He was one of the first pioneers in hydrocarbon exploration, especially around the anticlines with the mud volcanoes near Baku. In many respects, however, his fundamental ideas were erronous. He explained the structure of the Great Caucasus by the traditional theories of Leopold von Buch and Elie de Beaumont. The Caucasus anticline “was elevated by forces acting from beneath”. Following them he tried to discover regularities in the strike of mountain chains. Similarily he treated volcanism like Alexander von Humboldt and Leopold von Buch with their two groups of phenomena: voluminous, mostly basaltic “elevation craters” versus isolated, mostly trachytic and relatively small cones of “true volcanoes”. In spite of the isolation of the Caucasus region he had cultivated continuously contacts with leading geologists in Europe and was honoured by many institutions. He left Russia in 1876 for Vienna planning to write there the final monograph volumes about his investigations but he died before he could complete them.  相似文献   
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