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991.
B. Böhnke 《Aquatic Sciences - Research Across Boundaries》1964,26(2):494-510
Ohne Zusammenfassung 相似文献
992.
This paper measures the concepts of welfare and well-being in Russia on the basis of two large Russian household surveys, carried out in 1993 and 1994. Welfare refers to satisfaction with income and well-being refers to satisfaction with life as a whole. This paper investigates how climate conditions in various parts of Russia affect the cost of living and well-being. Climate equivalence scales have been constructed for both welfare and well-being. 相似文献
993.
A system is presented in which an atmosphere containing less than 10?6 mole fraction oxygen and water containing less than 5 ppb oxygen can be maintained. Flotation of chalcocite, chalcopyrite, galena, pyrite and sphalerite in this system reveals that these minerals are naturally floatable under these conditions. 相似文献
994.
995.
996.
A broken ore-vein is very common in nature. A small scale model of such a vein has been made by placing two thin metal sheets edge to edge with an air gap between them. The electromagnetic response of this model in a uniform oscillating magnetic field has been measured. The results show that (a) the response of the whole body is not the sum of responses of the constituent parts, (b) the response of the upper part is dominant by virtue of its proximity to the receiving coil and (c) the lower part has the effect of making the upper part appear nearer to the surface and poorer in conductance than it really is. 相似文献
997.
Prof. S. Capedri Prof. C. B. Gomes Prof. G. Rivalenti Dr. E. Ruberti 《Mineralogy and Petrology》1976,23(3):175-190
Summary Microprobe analyses of olivines, orthopyroxenes and clinopyroxenes of the Ivrea-Verbano basic formation reveal that in the Balmuccia Periodotites (regarded as residual mantle) the phases are more magnesian than in the overlaying ultramafic-mafic series (interpreted as a cumulitic complex formed by fractionation of mantle-derived magma).Pyroxenes underwent sub-solidus re-equilibration. Whole phase (host + exsolved lamellae) compositions give a temperature in the range 946°C–1236°C, compatible with the igneous crystallisation. The compositions of the host phases give temperatures in the range 712°C to 919°C, indicating that the samples did not attain the same degree of equilibrium during the sub-solidus unmixing. The sub-solidus unmixing of the pyroxenes may have occurred either during the superimposed granulite-facies metamorphism or during the slow cooling of the complex intruded into deep crustal levels.
With 4 Figures 相似文献
Pyroxene und Olivine als Indikatoren der petrologischen Entwicklung der basischen Formation von Ivrea-Verbano (Italienische Westalpen)
Zusammenfassung Mikrosondenanalysen von Olivinen, Orthopyroxenen und Klinopyroxenen der basischen Formation von Ivrea-Verbano zeigen, daß in den Balmuccia Peridotiten (die als residuales Mantelmaterial angesehen werden) die Phasen Mg-reicher sind als in den überlagernden ultramafischen bis mafischen Serien (die als Kumulationskomplex gedeutet werden, der durch Fraktionierung eines aus dem Mantel stammenden Magmas gebildet wurde).Die Pyroxene wurden unter Subsolidus-Bedingungen reequilibriert. Die Zusammensetzungen der Gesamtphasen (Wirt + Entmischungslamellen) geben Temperaturen im Bereich von 946–1236°C, was mit einer magmatischen Kristallisation verträglich ist. Die Zusammensetzungen der Wirt-Phasen geben Temperaturen im Bereich von 712–919°C an, was anzeigt, daß die Proben während der Subsolidus-Entmischung nicht denselben Grad der Equilibirierung erreichten. Die Subsolidus-Entmischung der Pyroxene kann entweder während der überlagerten Metamorphose in Granulitfazies oder während der langsamen Abkühlung des in tiefe Krustenschichten intrudierten Komplexes geschehen sein.
With 4 Figures 相似文献
998.
B. L. N. Kennett 《Pure and Applied Geophysics》1976,114(4):647-652
The effects of unsuspected lateral variation in seismic velocities at depth on the interpretation of a seismic refraction profile are discussed with the aid of a numerical experiment. The results show that there will be bias in any velocity depth models derived by travel time analysis based on the assumption of horizontally layered media. This bias is examined for a lithospheric profile using both extremal and linearised travel time inversion. In addition quite mild subsurvace topography can have an appreciable effect on the amplitude distribution along the profile. 相似文献
999.
1000.
An analysis of observations of airflow over Lake Ontario in a stably stratified atmosphere is presented. The relationship with theory is mentioned only in terms of what may be important to future work. Detailed air motion, potential temperature and mixing-ratio measurements are presented which show pervasive variability in the horizontal. There is no evidence of gravity waves. It is suggested that vertical mixing of the atmosphere may occur in stable conditions by a mechanism quite apart from the usual concept of the small-scale random eddy motion usually associated with surface convection. Vertical soundings are analyzed as well as two long constant-height observational runs. 相似文献