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961.
Let (A) be the coefficient of the second term in the Laurentexpansion about T 1 of the Poincare series p(A, t) of a gradedring A. For a finite extension of integrally closed domains,we prove a formula relating if (B), if (A) and the differentialexponent of B over A. As an application, we prove a conjectureof Carlisle and Kropholler which computes for rings of modularinvariants of finite groups in terms of stabilizers of hyperplanes. 相似文献
962.
For the functional differential equationu (n) (t)=f(u)(t) we have established the sufficient conditions for solvability and unique solvability of the boundary value problems $$u^{(i)} (0) = c_i (i = 0,...,m - 1), \smallint _0^{ + \infty } |u^{(m)} (t)|^2 dt< + \infty $$ and $$\begin{gathered} u^{(i)} (0) = c_i (i = 0),...,m - 1, \hfill \\ \smallint _0^{ + \infty } t^{2j} |u^{(j)} (t)|^2 dt< + \infty (j = 0,...,m), \hfill \\ \end{gathered} $$ wheren≥2,m is the integer part of $\tfrac{n}{2}$ ,c i ∈R, andf is the continuous operator acting from the space of (n?1)-times continuously differentiable functions given on an interval [0,+∞] into the space of locally Lebesgue integrable functions. 相似文献
963.
964.
D. Indumathi 《Pramana》1995,45(1):155-171
This talk discusses the current understanding in some aspects of polarised lepton-nucleon deep inelastic scattering. The first section focuses on the non-singlet part of available spin dependent structure function data. The results, though consistent with theoretical predictions in this sector, are extremely sensitive to extrapolation of the data to thex→1 region and seem to indicate that the quarksdo carry a very small fraction of the nucleon spin. We then review the formalism of DIS processes with emphasis on the gluon sector. 相似文献
965.
R. Casalbuoni S. De Curtis D. Dominici P. Chiappetta A. Deandrea R. Gatto 《Zeitschrift fur Physik C Particles and Fields》1995,67(2):327-336
Decays and branching ratios of light neutralino production in $Z_R^0 \to \tilde \chi _i^0 \tilde \chi _j^0 $ in the left-right super-symmetric model are considered. We study in detail the signatures of one and two sided events in $Z_R^0 \to \tilde \chi _1^0 \tilde \chi _2^0 $ and $Z_R^0 \to \tilde \chi _2^0 \tilde \chi _2^0 $ respectively, and their dependence on the parameters of the light neutralino mixing matrix. 相似文献
966.
967.
This work is devoted to the determination of the vibrational population of hydrogen molecules in the ground and excited electronic states from the analysis of visible spectra of the H2 molecules excited by an RF discharge in an expanding thermal arc plasma. Comparison of the experimental results on relative electron-impact excitation cross sections for the transition H2(X1Σ, υ0 = 0)→ H2(d3IIu, υ′) with other experiments, and with calculations based on the Franck-Condon principle, shows good agreement. This means, that for plasma under investigation: 1) in the ground electronic state H2(d3IIu,υ′), only the lowest vibrational level with υ0 = 0 is significantly populated, and 2) direct electron exictation of H2(d3IIu, υ′, υ′) state from the ground state H2(X1Σ, υ0 = 0) dominates. 相似文献
968.
CW diode pumping and FM mode locking of a Nd: KGW laser 总被引:2,自引:0,他引:2
C. J. Flood D. R. Walker H. M. van Driel 《Applied physics. B, Lasers and optics》1995,60(2-3):309-312
We have demonstrated cw diode end pumping of Nd: KGW, a novel solid-state gain medium, with up to 30% conversion efficiency into near-TEM00 (M2 < 1.05) output at = 1.067 µm for a pump level of 2.7 W. The slope efficiency was limited by intracavity reflections to 36%; however, direct comparison to a similar Nd:YAG laser indicates the same intrinsic slope efficiency of 60%. FM mode locking of this laser at 200 MHz has produced 12 ps pulses (compared to 16 ps for Nd: YAG), although an intracavity etalon was required. Considerable reduction in pulse width is possible (the line width limit is 0.5 ps) but different techniques may be necessary. Spatial hole burning was evident in both the 120 GHz free-running spectrum and the etalon-limited mode-locked spectrum. 相似文献
969.
The solution of Burgers' equation with random initial conditions is often said to describe "Burgers turbulence." The Burgers equation describes two fundamental effects characteristic of any turbulence-the nonlinear transfer of energy over the spectrum and the dissipation of energy in the small-scale components. Strong interaction between coherent harmonics, associated with the nondispersive nature of the dynamics, leads to the appearance of local self-similar structure. In Burgers' equation, continuous random initial fields are transformed into sequences of regions with regular behavior, with random locations of the shocks separating them. Moreover, the statistical properties of such random fields are also self-similar. It is already known that the merging of the shocks leads to an increase of the external scale of the turbulence, and because of this the energy of a random signal ("noise") decreases more slowly than the energy of simple signals. Here we show that similar behavior takes place for complex regular signals with fractal structure in the coordinate or in the wave-number space. In all these cases, the law of increase of the external scale is determined by the behavior of the structure function of the integral of the initial field-i.e., the structure function of the initial action. (c) 1995 American Institute of Physics. 相似文献
970.
N. N. Kolos V. D. Orlov E. Ya. Yuzefovskaya F. G. Yaremenko N. P. Vorob'eva O. V. Shishkin Yu. T. Struchkov S. M. Ivkov 《Chemistry of Heterocyclic Compounds》1995,31(7):827-834
The reaction of 4-nitro-o-phenylenediamine with 4-nitro-4-R-chalcone dibromides affords the corresponding -(2-amino-4-nitroanilino)chalcones; x-ray diffraction data indicate that these are the Z-isomers. Experiments have been perfortned to determine the conditions required for cyclization of these compounds into 2, 4-diaryl7(8)-nitro-1, 5-benzodiazepines. In the solid phase or in ethanol solutions, these latter compounds exist primarily in the 3H tautomeric form; but in DMSO solutions, the 1H form predominates.Khar'kov State University, Khar'kov 310077. Institute of Heteroorganic Chemistry, Russian Academy of Sciences, Moscow 117813. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 7, pp. 950–958, July, 1995. Original article submitted June 30, 1994; revision submitted April 3, 1995.Deceased 相似文献