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991.
992.
G. V. Dubrovskiy A. V. Kuzmenko Yu. G. Markoff 《Theoretical and Mathematical Physics》1995,105(1):1291-1306
A three-dimensional lattice gas approximation for multilayer adsorbates is substantiated on the basis of statistical physics. In addition, some problems of equilibrium thermodynamics and kinetics are formulated, and a number of approximations are derived. A detailed kinetic theory of thin film growth, which is complementary to the applied approaches based on phenomenological models, thermodynamics of nonequilibrium processes, and solid medium and lattice gas models, is developed.Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 105, No. 1, pp. 130–148, October, 1995. 相似文献
993.
针对一般的非线性规划问题,利用某些Lagrange型函数给出了一类Lagrangian对偶问题的一般模型,并证明它与原问题之间存在零对偶间隙.针对具体的一类增广La- grangian对偶问题以及几类由非线性卷积函数构成的Lagrangian对偶问题,详细讨论了零对偶间隙的存在性.进一步,讨论了在最优路径存在的前提下,最优路径的收敛性质. 相似文献
994.
Yu. S. Dedkov 《The European Physical Journal B - Condensed Matter and Complex Systems》2007,57(1):15-19
The spin-resolved electronic structure of thin Cr overlayers on top of the Fe(110) surface was investigated by means of spin-
and angle-resolved photoelectron spectroscopy. The initial fast drop of photoelectron spin-polarization at the Fermi level,
followed by weak oscillatory behavior with the period of about 2 ML, can give an evidence for the first time spectroscopic
observation of the short period oscillations in (110)-oriented thin Cr films. 相似文献
995.
Zhitian Liu Lei Wang Junwu Chen Feng Wang Xiaoying Ouyang Yong Cao 《Journal of polymer science. Part A, Polymer chemistry》2007,45(5):756-767
2,5‐Bis(2‐bromofluorene‐7‐yl)silole was prepared by a modified one‐pot synthesis with a reverse addition procedure, from which novel silole‐containing polyfluorenes with binary random and alternating structures (silole contents between 4.5 and 25% and high Mw up to 509 kDa were successfully synthesized. The well‐defined repeating unit of the alternating copolymer comprises a terfluorene and a silole ring. Optoelectronic properties including UV absorption, electrochemistry, photoluminescence (PL), and electroluminescence (EL) of the copolymers were examined. The different excitation energy transfers from fluorene to silole of the copolymers in solution and in the solid state were compared. The films of the copolymers showed silole‐dominant green emissions with high absolute PL quantum yields up to 83%. EL devices of the copolymers with a configuration of ITO/PEDOT/copolymer/Ba/Al displayed exclusive silole emissions peaked at around 543 nm and the highest EL efficiency was achieved with the alternating copolymer. Using the alternating copolymer and poly(9,9‐dioctylfluorene) as the blend‐type emissive layer, a maximum external quantum efficiency of 1.99% (four times to that of the neat film) was realized, which was a high efficiency so far reported for silole‐containing polymers. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 756–767, 2007 相似文献
996.
N. O. Mchedlov-Petrosyan L. A. Fedorov S. A. Sokolovskii Yu. N. Surov R. Salinas Maiorga 《Russian Chemical Bulletin》1992,41(3):403-409
A study has been made of the acidic ionization, structural conversions, and prototropic tautomerism of rhodamine chromogens in methanol and dimethyl sulfoxide, using IR,
13
C NMR, and electronic spectroscopy. The lactone structure has been established for the colorless form of rhodamines in DMSO. For rhodamine B in mixtures of water with DMSO, the lactone/zwitterion ratio has been estimated.V. I. Vernadskii Institute of Geochemistry and Analytical Chemistry, Russian Academy of Sciences, Moscow 117975. Khar'kov State University, Khar'kov 310077. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 3, pp. 512–521, March, 1992. 相似文献
997.
998.
给出动态随机弹性的概念及运算性质,讨论了动态随机弹性在期权定价模型中的应用.主要结果有:(1)在波动率为常数时,期权价格对的弹性,得到了动态随机弹性服从运动,并给出了相应的经济解释;(2)由于波动率一般不是常数,也是随机过程,因此本文进一步研究了期权价格对波动率的弹性,就股票价格的波动情况给出了数学描述和金融意义上的解释. 相似文献
999.
We consider the interpolation Nevanlinna-Pick problem with infinitely many interpolation nodes in the class S[a, b] and rational matrix functions associated with this problem and orthogonal on the segment [a, b]. We obtain a criterion of complete indeterminacy of the Nevanlinna-Pick problem in terms of orthogonal rational matrix functions.
__________
Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 59, No. 6, pp. 764–770, June, 2007. 相似文献
1000.
V. E. Bening V. Yu. Korolev S. Koksharov V. N. Kolokoltsov 《Journal of Mathematical Sciences》2007,146(4):5950-5958