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161.
Summary With the aid of elementary methods of the theory of dimensionality we approach the problem of existence of invariants in the process of mixing particles of a passive admixture in a field of turbulence. 相似文献
162.
¶rt;mam mam a¶rt;u, m u a nuu mauu nu¶rt; 1970–1977. nauaumGs 11 No 131, 201 uGs 15 No 228. a¶rt; ¶rt;uam mauau ¶rt;u um. ¶rt;uu au naam nuu nu¶rt; ma. 2,uuu au ma. 3.
Paper presented at the IUGG XVII Plenary Meeting, Canberra, Dec. 1979. 相似文献
Paper presented at the IUGG XVII Plenary Meeting, Canberra, Dec. 1979. 相似文献
163.
V. B. Buryanov V. V. Gordienko N. I. Pavlenkova Reviewer I. Pšenčík 《Studia Geophysica et Geodaetica》1980,24(2):114-123
m¶rt; amamu ¶rt;uau nma nauua ¶rt; a n amu . n ¶rt;a uu u¶rt;au,aumuu u mn nma. mam maa auum ¶rt; m u nmm u¶rt;ua n¶rt;a u a maa a umua a nam . ¶rt; nmm amuu n¶rt;m uu 3,3/
3
, n¶rt; ¶rt;uuuau u na¶rt;uau mu a anma ¶rt; 3,2/
3
. ¶rt; n¶rt;uu a¶rt;u aau mum nm, maumaa ¶rt;¶rt;m aama u ¶rt; amu .
Presented at the KAPG Symposium Problems of Interpretation and Construction of Physical Models of Litosphere, Liblice (CSSR), March 6–10, 1978. 相似文献
Presented at the KAPG Symposium Problems of Interpretation and Construction of Physical Models of Litosphere, Liblice (CSSR), March 6–10, 1978. 相似文献
164.
165.
—Approximate PP plane wave displacement coefficients of reflection and transmission for weak contrast interfaces separating weakly but arbitrarily anisotropic elastic media are presented. The PP reflection coefficient for such an interface has been derived recently by Vavry?uk and P?en?ík (1997). The PP transmission coefficient presented in this paper was derived by the same approach. The coefficients are given as a sum of the coefficient for the weak contrast interface separating two nearby isotropic media and a term depending linearly on contrasts of the so-called weak anisotropy (WA) parameters (parameters specifying deviation of properties of the medium from isotropy), across the interface. While the reflection coefficient depends only on 8 of the complete set of the WA parameters describing P-wave phase velocity in weakly anisotropic media, the transmission coefficient depends on their complete set. The PP reflection coefficient depends on "shear-wave splitting parameter" γ. Tests of accuracy of the approximate formulae are presented on several models. 相似文献
166.
167.
Summary Approximate expressions for the Hilbert transform of the functionf(t)=exp(-
0
2
t
2/2) cos(
0
t+v) are determined. This function, given a suitable choice of the three parameters 0, and v, approximates a wide class of seismic signals very well. The approximate expressions for the Hilbert transform enable very simple formulae to be given for the elementary seismograms of the individual seismic body waves (in the zero approximation of the ray theory). This accelerates the computation of ray theoretical seismograms considerably. 相似文献
168.
Lowry's method, adapted to the analysis of small amounts of fresh-water plankton, was selected for the basic evaluation of the published methods of determination of proteins in algae. The protein contents were studied by this method in aqueous, alcohol and sodium hydroxide extract from green algae of the types Ankistrodesmus falcatus, Haematococcus pluvialis, Chlorella vulgaris, Scenedesmus obliquus, Pediastrum boryanum, Chlorococcus spec. and from blue-green algae Microcystis pulverea, M. aeruginosa and Anacystis nidulans. These organisms were cultivated in artificial media under standard conditions and the analysis of proteins was carried out during the growth and stagnation phases. The largest amount of proteins was ascertained in extracts of 2N NaOH, amounting to 7 … 44% according to the dry substance (aqueous extract 1 … 48%, alcohol extract 1 … 23%). As the ageing of the cultures of green algae proceeded, the amount of dry substance increased, but the protein contents decreased. In the samples of blue-green algae there were in all cases the protein contents higher in the stationary phase than in the growth phase. 相似文献
169.
Alexander Roglinov Ludmil Christoskov Reviewer J. Vaněk 《Studia Geophysica et Geodaetica》1977,21(1):11-18
Summary Aki's spectral 2 model[1] is used to estimate the amplitude field at epicentral distances up to 1000 km in the case of an absorption coefficient of seismic waves which varies with distance. Velocity spectra, the periods of the maximum of these spectra and the maximum velocity amplitudes are obtained. The results are compared with[2] and it is shown that the divergence of the amplitude field decreases if a variable absorption coefficient is used. The theoretical results, obtained in this case, approach the results seen in practice. The possibility of determining the limits of epicentral distances, at which the amplitude field may be considered as linear, is given. 相似文献
170.
Summary Three quantities M, E
1/2
and E
2/3
are used for studying the Balkan earthquake provinces. Most of them show a regular trend of activity, for some of them the observation period of 70 years is too short. Some graphs give evidence of the coincidence or migration of activity. 相似文献