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891.
M. Miyake R. W. Stewart R. W. Burling L. R. Tsvang B. M. Koprov O. A. Kuznetzov 《Boundary-Layer Meteorology》1971,2(2):228-245
In the fall of 1968 an International Intercomparison Experiment was conducted to compare, among other things, acoustic anemometers designed for measurements of atmospheric turbulence. Excellent agreement was obtained in measurements of the vertical component, but an important discrepancy was revealed in measurements of the downwind velocity. The discrepancy proved far more significant in the cospectra than in the spectra themselves. It is evident that great care must be taken in the design of such instruments. An acoustic instrument was shown to have insufficient signal-to-noise ratio to serve as a thermometer under the near-neutral conditions often encountered over water.Comparison of the data-handling and data-analysis techniques showed that although the methods differed widely, the results were essentially identical. 相似文献
892.
Prof. Dr.-Ing. B. Böhnke 《Aquatic Sciences - Research Across Boundaries》1969,31(2):558-564
Ohne Zusammenfassung 相似文献
893.
894.
J. B. Wright 《International Journal of Earth Sciences》1968,58(2):538-564
Sub-alkaline to calc-alkaline granite dominates the high-level plutonic massif of the Serra de Sintra, while two overlapping ring complexes recognised within it consist of four distinct alkaline to sub-alkaline quartz-bearing syenitic units, together with intrusions of a remarkable kaersutite- and (titan?)biotite-bearing theralite heteromorph (Mafraite), contaminated to varying degrees by sialic admixture. Large volumes of sub-volcanic breccia testify to considerable late explosive activity in and near the ring centres. Minor intrusives are approximate compositional counterparts of the plutonic rocks, but more closely resemble lavas forming the extensive “basaltic mantle” of the Lisbon region, where compositions range from olivine basalt, basanite and theralite (luscladite) to subordinate quartz-bearing trachyandesite and trachyte. Undersaturated salic rocks are absent throughout the province. Magmatic differentiation probably played a minimal part in petrogenesis of the Sintra intrusives. The granite is interpreted as a direct product of basement syntexis, the other rocks as products of selective palingenetic reactions between mafraitic magma and crystalline basement (or granite). Evolution of the volcanic and hypabyssal rocks may have been controlled by similar reactions, but evidence favouring differentiation of this suite from sialcontaminated basic parents is almost as strong. There are some points of resemblance between this province and that of the Auvergne region in southern France. 相似文献
895.
896.
897.
The authors describe from the South of Brittany (inverted limb of the “overthrust nappe of Champtoceaux”, near Nantes) an
example of a relic massif of “charnockitised” granite, within augen gneisses and blastomylonitic leptynites. The granite is
characterised by the presence of coronas of almandite + orthoclase between biotite (ores) and plagioclase, indicating that
it was affected by a pre-deformation granulitic phase of metamorphism before its retromorphism in the amphibolite and greenschist
facies, a similar history is recorded in associated metabasites. The progressive transformation of granite to augen gneisses
and leptynites is a new observation of importance concerning the origin of leptynites.
相似文献
898.
Summary The growth equation for the pressure shocks as conceived by Thomas and Edstrom (1961), in a thermally and electrically conducting viscous gas has been derived. Ionisation and dissociation have not been taken into account, while the effects of radiation have been considered under the assumption that the radiative parameters are independent of magnetic field. During the course of derivation certain boundary conditions and the well known compatibility conditions established by Thomas (1957) have been used. 相似文献
899.
The various extinctions of marine taxa in the Late Cenomanian can be shown as conforming to the 'step-wise extinction' model. The order of such extinctions is, however, compatible with the presence of an expanded oxygen minimum zone in the world ocean. The occurrence of iridium anomalies at this level in the succession may, however, indicate a volcanogenic control on the global environment. Detailed time-analysis of the Late Cenomanian event has been used to produce a correlation of some key successions. 相似文献
900.