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991.
This note introduces a refinement to a previously proposed tabu search algorithm for vehicle routing problems with time windows. This refinement yields new best known solutions on a set of benchmark instances of the multi-depot, the periodic and the site-dependent vehicle routing problems with time windows. 相似文献
992.
993.
Leonard M Khalilov Ludmila V Parfenova Askhat G Ibragimov Usein M Dzhemilev 《Journal of organometallic chemistry》2004,689(2):444-453
This paper is dedicated to a study of properties of the following novel optically active organoaluminium compounds (OACs): (1S,2S)-l,7,7-trimethyl-2-[(dialkylalumina)oxy]-bicyclo[2.2.1]heptanes and (1S)-N-(dialkylalumina)-6,7-dimethoxy-1-methyl-1,2,3,4- tetrahydroisoquinolines. The synthesis of the chiral OACs was carried out in the reaction of either natural camphor or salsolidine with both AlEt3 and i-Bu2AlH. The main goal of the research was to investigate the stereodifferentiating activity of the chiral OACs in the olefin carbo- and cycloalumination reactions, catalyzed by Cp2ZrCl2. 相似文献
994.
Yu. V. Sanochkin 《Technical Physics》2003,48(5):546-551
It is shown that, along with gravity waves, surface and internal waves caused by van der Waals forces may exist in a liquid
with a horizontal free surface. A dispersion relation is found by using the stepwise approximation for the coefficients of
a wave equation derived for these waves. The surface waves are similar to surface gravity waves in dispersion and amplitude
distribution but differ in frequency by several orders of magnitude. Another sequence of roots in the spectrum corresponds
to internal van der Waals waves that have an upper frequency bound and the dispersion law typical of a multimode waveguide. 相似文献
995.
Salimgareeva V. N. Polevoi R. M. Kolesov S. V. Ostakhov S. S. Ponomareva V. A. Leplyanin G. V. 《Russian Journal of Applied Chemistry》2003,76(5):804-808
The luminescence and scintillation properties of poly(methyl methacrylate) containing 1,1,3-trimethyl-3-phenylindan were studied. 相似文献
996.
S. S. Andreev A. D. Akhsakhalyan M. A. Bibishkin N. I. Chkhalo S. V. Gaponov S. A. Gusev E. B. Kluenkov K. A. Prokhorov N. N. Salashchenko F. Schafers S. Yu. Zuev 《Central European Journal of Physics》2003,1(1):191-209
We present research investigations in the field of multilayer optics in X-ray and extreme ultra-violet ranges (XUV), aimed
at the development of optical elements for applications in experiments in physics and in scientific instrumentation. We discuss
normal incidence multilayer optics in the spectral region of “water window”, multilayer optics for collimation and focusing
of hard X-ray, multilayer dispersing elements for X-ray spectroscopy of high-temperature plasma, multilayer dispersing elements
for analysis of low Z-elements. Our research pays special attention to optimization of multilayer optics for projection EUV-lithography
(ψ-13nm) and short period multilayer optics. 相似文献
997.
M.V. Nazarov J.H. Kang E.-J. Popovici B.S. Tsukerblat 《Solid State Communications》2005,133(3):183-186
Samples of yttrium oxide doped with trivalent europium have been prepared by ceramic techniques, under different synthesis conditions; barium chloride (BaCl2) and sodium tetraborate (Na2B4O7) were tested as flux. The improvement of luminescence properties in dependence on substitution of Eu3+ for Y3+ in the host lattice, under electron and UV excitations is demonstrated. The lattice parameter as a quantitative assessment of activator incorporation degree is proposed. The obtained results are discussed with respect to the employed processing method. 相似文献
998.
K. Zhang 《Calculus of Variations and Partial Differential Equations》2003,17(1):85-103
Let be a linear subspace of real matrices without rank-one matrices and let be a finite set. Suppose is a bounded arcwise connected Lipschitz domain and is a sequence of bounded vector-valued mappings in such that in as , where is the closed -neighbourhood and the distance function to . We give estimates for such that up to a subsequence, in for some fixed . In other words, we give estimates on such that separates gradient Young measure. The two point set with is a special case of such sets up to a translation.
Received: 20 July 2001 / Accepted: 23 January 2002 / Published online: 5 September 2002 相似文献
999.
1000.
We consider some types of packet discretization for continuous spectra in quantum scattering problems. As we previously showed, this discretization leads to a convenient finite-dimensional (i.e., matrix) approximation for integral operators in the scattering theory and allows reducing the solution of singular integral equations connected with the scattering theory to some suitable purely algebraic equations on an analytic basis. All singularities are explicitly singled out. Our primary emphasis is on realizing the method practically. 相似文献