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排序方式: 共有10000条查询结果,搜索用时 12 毫秒
991.
Yu. K. Voron'ko A. B. Kudryavtsev V. V. Osiko E. V. Sorokin 《Journal of Applied Spectroscopy》1991,55(4):953-957
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 55, No. 4, pp. 535–540, October, 1991. 相似文献
992.
993.
Nathaniel A. Friedman 《Israel Journal of Mathematics》1989,68(3):365-375
A weakly mixing transformationT and a sequence (d
n) are constructed such thatT is uniformly mixing on (d
n),T is uniformly sweeping out on ([αd
n]) for allα∈(0, 1), and for all rationalα∈(0, 1)T is not mixing on ([αd
n]). 相似文献
994.
R. J. Vanderbei 《Mathematical Programming》1989,43(1-3):31-44
The affine-scaling modification of Karmarkar's algorithm is extended to solve problems with free variables. This extended primal algorithm is used to prove two important results. First the geometrically elegant feasibility algorithm proposed by Chandru and Kochar is the same algorithm as the one obtained by appending a single column of residuals to the constraint matrix. Second the dual algorithm as first described by Adler et al., is the same as the extended primal algorithm applied to the dual. 相似文献
995.
996.
Volker Elling. 《Mathematics of Computation》2006,75(256):1721-1733
A particular case of initial data for the two-dimensional Euler equations is studied numerically. The results show that the Godunov method does not always converge to the physical solution, at least not on feasible grids. Moreover, they suggest that entropy solutions (in the weak entropy inequality sense) are not well posed.
997.
5‐Amino‐4‐methyl‐2‐phenyl‐6‐substitutedfuro[2,3‐d]pyrimidines ( 2a‐c ) were reacted with 2,5‐dimethoxytetrahydrfuran to afford the pyrrolyl derivatives 3a‐c . Compound 3a was chosen as intermediate for the synthesis of poly fused heterocycles incorporated furopyrimidines moiety 4–11 . Some of the synthesized compounds were screened for their antibacterial and antifungal activities. 相似文献
998.
V. M. Marchenko 《Laser Physics》2006,16(6):981-984
The visible luminescence of Er2O3 powder induced by CO2 laser radiation with a wavelength of 10.6 μm is observed and spectrally studied. The mechanisms for the CO2 laser radiation’s conversion into the luminescence are discussed. The experimental results can be used for the creation of
large-screen devices for displaying, visualization, and digital photo and video detection of the intensity distributions,
spectra, and interferograms of laser radiation.
Original Text ? Astro, Ltd., 2006. 相似文献
999.
A new geometrical method to determine the surface damage threshold for ultrashort pulses is presented. It consists in the formation of a surface damage profile by a movement of the sample across the laser beam focus. A single measurement of the maximum transversal dimension of this damage profile, which depends solely on the laser beam power, is used to calculate the local damage threshold intensity. It is also theoretically shown that the damage in the transverse dimension can be controlled under the diffraction-limited spot. 相似文献
1000.