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971.
972.
Summary Global average temperatures from 1860 to 1989 were analysed with a simple fitting procedure. The temperature records can be
fitted with a rising exponential up to 1946 and with the same exponential minus an increasing cooling action from 1946 to
1989. It is shown that the results are compatible with the hypothesis of an albedo increase caused by SO2 emissions. This hypothesis gives satisfactory explanations of the temperature drop in the years 1940–1970, of the different
warming of the northern and southern hemispheres and of the slower warming observed over North America. The results give an
indication that the greenhouse warming in the next years could be faster than predicted until now.
Due to the relevance of its scientific content, this paper has been given priority by the Journal Direction. 相似文献
973.
A new microscopic model of anomalous muonium for the elemental semiconductors is proposed. The relevant configuration consisting
of both a diamagrentic molecule Si−Mu and an unpaired orbital e− is contained into a semivacancy of the real lattice. By using the unrestricted Hartree-Fock computational method the principal
properties of the system are established. A dynamical version of the model together with a question on the formation of such
system are discussed. 相似文献
974.
An explicit expression is obtained for the Green's functions of a massive scalar field for nonnull temperatures and density in the form of a series in powers of m/T. The equivalence of the spectral-geometric approach and the temperature technique of Matsubara and Bernard is demonstrated. Corrections to the Stefan-Boltzmann law are obtained on the basis of the calculated Green's functions. The energy density is calculated in regions of high and low temperatures. The formulas obtained can prove to be useful in the discussion of the phase transition hadrons-quark-gluon plasma.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 7, pp. 32–40, July, 1991. 相似文献
975.
976.
V. V. Skopetskii V. S. Deineka S. I. Rybachishin 《Journal of Mathematical Sciences》1992,58(5):426-434
The problem of zero-head seepage through a cutoff is reduced to solving a variational inequality which is discretized by the finite element method. The discrete variational inequality is solved by a two-layer iterative process. A rate of convergence bound is obtained for the approximate solution and the optimal parameters of the two-layer iterative process are determined. A numerical experiment supports the theoretical results.Translated from Vychislitel'naya i Prikladnaya Matematika, No. 58, pp. 45–56, 1986. 相似文献
977.
978.
Laser gas-assisted material processing finds wide application in industry. The modelling of heating, elastic response of the substrate material, and the wave analysis gives insight into the laser workpiece interaction. In the present study, laser gas-assisted heating of steel is considered. The normal component of the thermal stress is taken as the source of load for the flexural wave generation in the material. The flexural wave generated is simulated and the wave characteristics are analyzed at four locations at the workpiece surface. The numerical scheme employing a control volume approach is introduced when solving the governing equations of flow and heat transfer while finite element and spectran element methods are used when solving the stress and wave equations. It is found that the normal component of the stress is tensile. The dispersion effect of the workpiece material, interference of the reflected beam, and partial overlapping of second mode of the travelling wave enable to identify a unique pattern in the travelling wave in the substrate. 相似文献
979.
We analyze the analog of the Kelvin-Helmholtz instability on the free surface of a superfluid liquid. This instability is
induced by the relative motion of superfluid and normal components of the same liquid along the surface. The instability threshold
is found to be independent of the value of viscosity, but turns out to be lower than in the absence of dissipation. The result
is similar to that obtained for the interface between two sliding super-fluids (with different mechanisms of dissipation)
and confirmed by the first experimental observation of the Kelvin-Helmholtz instability on the interface between 3He-A and 3He-B by Blaauwgeers et al. (cond-mat/0111343). 相似文献
980.
E. R. Bauminger E. Fibach A. M. Konijn S. Ofer E. A. Rachmilewitz 《Hyperfine Interactions》1991,66(1-4):11-23
Mössbauer studies in murine (MEL) and human K-562 erythroleukemia cell lines have been utilized to study the fate of iron during intracellular Hb synthesis and denaturation. The results showed that ferritin can serve as an intermediate iron pool for Hb synthesis and for storage of iron released during intracellular Hb denaturation. 相似文献