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981.
Jan Kozák Jan Šílený Aleš Špičák Reviewer V. Červený 《Studia Geophysica et Geodaetica》1984,28(2):156-163
¶rt;u u uu uuu ¶rt; n¶rt; ¶rt;au m ¶rt;u uu m n¶rt;uu u numuu m¶rt;. mam n¶rt; aamumuu anamu u ; n¶rt; mu aaa amu ¶rt;u n¶rt;uu nmu aua ¶rt;u u uu a mu m muna. 相似文献
982.
František Jiříček Pavel Tříska E. E. Titova T. A. Yakhnina O. A. Maltseva Reviewer S. Fischer 《Studia Geophysica et Geodaetica》1986,30(4):411-416
Summary The elements of the VLF chorus, observed simultaneously at a ground station and satellite in polar orbit, can be used to determine the differences in the arrival times of waves and their dependence on latitude. Mostly does not change practically over a wide range of latitudes, however, in some cases it may increase appreciably at low value of L. Model computations of the propagation time, based on the assumption that the source of the chorus is located close to the equatorial plane, have indicated the possibility of explaining the increase in at low latitudes by the presence of a step in the electron density profile close to this plane.
a¶rt;u m a u a um nmu nun um nm n¶rt;um amu u nu¶rt;a ma a u u um auum (L). um a a m ¶rt;uana um, m a a¶rt;am aum uu a a L-a. am anmau n¶rt;nuu amua umua naam m um uu a uu uma auu mnu an¶rt;uu m mauu amua nmu.相似文献
983.
Summary The paper deals with a comparison of two models used in determining the heat flow qM at the lower boundary of two-dimensional geothermal models of the Earth's crust. Method I is based on a linear relationship between the component of the surface heat flow, which is not generated by heat sources inside the model, and the heat flow qM. This method uses a regularization process, in which the variation of the sought function qM is limited from above. Method II is the most frequently used iterative method, in which the (i + 1)-th approximation of qM is determined from the surface heat flow, corresponding to the i-th approximation of qM used as a boundary condition in solving the direct problem. The comparison of both methods has revealed that the solution obtained by method I satisfies the supposed reality better than the solution obtained by method II. Method II is attractive especially for its simplicity. To eliminate the local variations of the estimated heat flow qM, which are due to automatic transmission from the surface heat flow, a combination of method II with some smoothing procedure could be applied.
¶rt;am ¶rt;a m¶rt;a uu mn nma qM a uau ¶rt; muu ¶rt; . m¶rt; unm u ¶rt; ma nm nma, ma uaa umuau mna mu ¶rt;u, u nm qM. m m¶rt; nu n uauu, auuau auau u uu qM . m m¶rt;, mu nm ¶rt; u n a , umau: (i + 1)-a annuau nma qM um n auma nm nma, ma i- annuauu qM. au ¶rt;m, m nm qM, a¶rt; n m¶rt;, mam n¶rt;naa ¶rt;mummu , u, n m m¶rt;. m m¶rt; nuam nmm. ¶rt; mau a auau a¶rt; nma qM, uu ¶rt;mu amamu na u auau nm nma, ¶rt;a uuam au-u¶rt; m¶rt; auau.相似文献
984.
Jaroslav Kubík Vladimír Čermák Reviewer A. Janáčková 《Studia Geophysica et Geodaetica》1986,30(4):376-393
Summary The area of the Upper Silesian Coal Basin was characterized by generally high heat flow ranging from 60 to 120 mWm–2, mean 82±16 mWm–2, which has been difficult to explain. Therefore all published data on the heat flow in this region (n=37) were summarized and re-evaluated. Special attention was paid to the detailed assessment of the lithological structure and the contribution of the individual rock types to the characteristic in-situ thermal conductivity. Also the thermal conductivity of the coal bearing layers was estimated and its effect on the temperature-depth distribution was investigated. The application of the data obtained for the representative thermal conductivity profiles of the whole drilled section considerably reduced the mean heat flow to 70±8 mWm–2. The latter value is fully compatible with the tectonic structure of the northern part of the Carpathian Frontal Foredeep. Slightly increased geothermal activity compared with the heat flow field of the adjacent part of the Bohemian Massif corresponds to certain deep geological rejuvenation during the creation of the Western Carpathians.
a -uu aa aamum nu uuau mn nma (m 60 ¶rt; 120 m.–2 nu ¶rt; 82±16 m. –2), m ¶rt;a ¶rt u. m u u nm a nua ¶rt;a mn nma (n=37) ¶rt; ¶rt;a ua. ua ¶rt; ¶rt;ma aau umuu aa u u mnn¶rt;mu in situ ¶rt; a¶rt; muna n¶rt;. a a mnn¶rt;m m, a ma, a ma u¶rt;aa an¶rt;u mnam nu. nau n mam ¶rt; nuau mnn¶rt;mu m u amu aa nu am uum ¶rt;u mn nm ¶rt; 70±8 m.–2. a uua n mam mmu u amu anam a nua. m uumu amumu n au mn n nuaa amu aua mmmmuuau amuuauu nu uauu um ana¶rdt; anam.相似文献
985.
The top five centimeters of sediment collected at the deepest point of Lake Léman (Switzerland), 309 meters below water level, contain concentrations of 5α(H)-cholestan-3α-ol (epicholestanol) up to 10% of the total sterol content. Isobutane chemical ionization mass spectrometry and coinjection with an authentic standard on a SP-1000 glass capillary column were used in order to successfully characterize this epimer of cholestanol.The distribution of this stanol throughout the sediment core studied suggests in situ bacterial production. The change in concentration of epicholestanol with depth is different from those found for other C27 stanols, such as cholestanol or coprostanol. It is probably the result of a change in the bacterial fauna in the most recently deposited sediment, related to the increasing eutrophication of the lake rather than the consequence of its lower stability due to the axial conformation of the OH substituent. 相似文献
986.
Summary The degree of astaticism is the fundamental parameter of an astatic magnetometer, an instrument used in geophysics for magnetic measurements of rock specimens. The degree of astaticism is formulated with a view to the vectorial character of the defining quantities and with a view to the effect of the geomagnetic field. As regards measuring the parameter, the mirror method is given, which makes use of the positive and negative orientation of the astatic system relative to the north or east. The measure of the value of the parameter is the change of the sensitivity of the system and the deflection of its zero position, compensated for by the magnetic field of the calibration coil. The problem of the degree of astaticism is treated complexly, inclusive of the measurement of the parameter, which in practice is of fundamental importance for adjusting the systems for manufacturing astatic magnetometers. 相似文献
987.
Change of structure,phase composition and magnetic properties with the oxidation of titanomagnetites
T. S. Gendler Vladimír Kropáček Reviewer K. Zapletal 《Studia Geophysica et Geodaetica》1979,23(1):42-54
Summary Phase, structural and magnetic changes, occurring under oxidation and at increased temperatures, are studied on four samples of magnetic fractions. The samples of magnetic fractions, containing titanomagnetites at different oxidation levels, were oxidized at a temperature of 400°C for 1, 60 and 300 mins. With the aid of X-rays and Mössbauer's spectrometry it has been proved that under oxidation non-stoichiometric titanomagnetites and titanomagnetites plus ilmenite and pseudobrookite are formed. 相似文献
988.
ma mam m n, a uum am mua ¶rt;uu ana¶rt; anam. am n a a u¶rt; m um u n u mmu n¶rt;u ¶rt;uu. ¶rt; u n mam a n muu amu amu mam nm uu u n m¶rt;u mau am ¶rt;uu nmu, ma u n u¶rt;au ¶rt;uauu . am unam m ¶rt; a , u u¶rt;uu u mu namu nu nmuauu n u u, ammu uu¶rt;muu u a a. 相似文献
989.
mm ¶rt;u um a z num a / mua a (¶rt; ¶rt;u) a a n umnmauu yaumau u uu ¶rt;a. mam unau a um aau u mmu, ma¶rt;amy an¶rt;u nmmu u m¶rt; umnmauu am u m¶rt; auam ¶rt;o ¶rt;o. ¶rt;am namua ma¶rt;amo n¶rt;¶rt;a nmu u m nmm ¶rt;. 相似文献
990.
Summary This paper is a continuation of[1]. It is mainly devoted to problems connected with the application of the method of determination of geometrical spreading in laterally inhomogeneous media with curved interfaces based on the solution of eight (in a three-dimensional medium) or two (in a two-dimensional medium) linear ordinary differential equations of the first order. The method of determination of the partial derivatives of velocity with respect to the special coordinates, connected with the ray under investigation, and the methods of determination of the initial values for the system of differential equations at the source and at the interfaces are proposed. 相似文献