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131.
Kurt Pietzsch 《International Journal of Earth Sciences》1918,9(3-6):98-103
Ohne Zusammenfassung 相似文献
132.
Prof. Dr. Kurt Wegener 《Pure and Applied Geophysics》1952,22(3-4):205-236
Summary History and results of a 41/2-years-expedition to Argentine. A determination of the sun's «temperature» can only be given by the laws ofBoltzmann-Stefan andWien, because the temperature of the different layers is different. In the measurements of the sun's radiation the law ofBoltzmann-Stefan was introduced (T
4, where is a constant, andT the Kelvin-Temperature) while in the passed 100 years the difference between the sun's and the instruments radiation was taken as radiation, although this difference was arbitrariously variable with the instruments temperature. The effect of the vertical exchange of airmasses, on the radiation of the sun and the radiation of the air between the sun and the instrument was cleared. With these corrections one can not receive more as the difference between the so called solar constant and the albedo of the atmosphere. If the highest values are used (smallest albedo) the approximated value of the solar constant becomes 2.4, corresponding well to the value, derived from the supposed temperature of the sun. 相似文献
133.
Prof. Dr. Kurt Wegener 《Pure and Applied Geophysics》1943,5(1-2):107-110
Riassunto Usufruendo delle più recenti serie di misure della gravità, l'A. esamina la distribuzione di tale grandezza lungo alcuni profili degli Oceani Atlantico, Pacifico e Indiano, traendone diverse conclusioni e confermando precedenti risultati.
Zusammenfassung Auf Grund der neueren Reihen der Schweremessungen auf dem Meer, untersucht der Verf. die Schwereverteilung längs einiger Profile des Atlantischen, des Pazifischen und des Indischen Ozeans; daraus zieht er einige Schlussfolgerungen und bestätigt andere schon bekannte Ergebnisse.相似文献
134.
135.
Kurt Leuchs 《International Journal of Earth Sciences》1939,30(3):353-356
Ohne Zusammenfassung 相似文献
136.
Kurt Wegener 《International Journal of Earth Sciences》1938,30(1-2):3-5
Ohne Zusammenfassung 相似文献
137.
138.
Northern Adriatic Rocky Reef Fishes at Low Winter Temperatures 总被引:1,自引:0,他引:1
Abstract. The behavioural ecology of certain northern Adriatic fishes was observed from January to April at a water temperature of 7–11 o C. The fishes studied here do not migrate to deeper waters. Most of the benthic fishes show a similar distribution over the substrate in winter and in summer; in winter, however, they are very inactive and hide in the substrate. Suprabenthic fishes aggregate in littoral caves where they form dense, inactive, mixed aggregations. Certain hemipelagic and pelagic fishes join to form very dense aggregations at specific sites in the open waters of bays. Littoral predators display high feeding activity at a time when their prey is inactive. I present a hypothesis concerning possible implications of seasonally cyclic environmental temperatures for a sympatric community of non-migrating fishes. 相似文献
139.
Systems for the determination of trace element compounds consisting of liquid chromatographs (LC) (high pressure liquid chromatographs, ion chromatographs) and graphite furnace atomic absorption spectrometers (GFAAS) or inductively coupled argon plasma emission spectrometers (ICP) as single- or multi-element-specific detectors are described. The applications of these systems to the determination of arsenic compounds are reviewed. The absolute detection limits of these systems for arsenic are in the low nanogram range. These detection limits can probably be improved by two-three orders of magnitude by coupling an inductively coupled argon plasma-mass spectrometer instrument to the liquid chromatograph. The advantages and drawbacks of the LC-GFAAS and LC-ICP systems are outlined. These systems can separate and identify trace element compounds that are kinetically or thermodynamically stable under the conditions of the chromatography. Labile compounds cannot be determined by these systems. Wide application of these systems to problems of trace element research will lead to the identification of hitherto unknown trace element compounds, to a better understanding of the nutritional and toxic properties of trace element compounds, and to a better definition of trace element cycles. 相似文献
140.
Hurricanes David (August 29–30, 1979) and Frederick (September 2–5, 1979) caused major flooding of the Rio de La Plata in
northern Puerto Rico. A thin mud layer was deposited across the narrow insular shelf adjacent to the river mouth. Within 5
months, fair-weather shelf-winnowing processes moved the mud layer entirely from the shelf, 0.5 to 2 km to the shelf break
at the 50-m contour and beyond. The process of mud movement is termed “mud hopping.” 相似文献