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991.
利用推广的Hartle-Hawking假设,研究了4+2D维Einstein-Maxwell量子宇宙,计算了微超空间波函数的近似解.发现当D≤2时存在与观测宇宙相符合的暴胀解. 相似文献
992.
993.
A. S. Krinitsyn V. V. Prudnikov P. V. Prudnikov 《Theoretical and Mathematical Physics》2006,147(1):561-575
We consider how the Padé-Borel, Padé-Borel-Leroy, and conformal mapping summation methods for asymptotic series can be used
to calculate the dynamical critical exponent for homogeneous and disordered Ising-like systems.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 147, No. 1, pp. 137–154, April, 2006. 相似文献
994.
Shunsuke Suzuki Akira Nakajima Munetoshi Sakai Naoya Yoshida Yoshikazu Kameshima Kiyoshi Okada 《Surface science》2006,600(10):2214-2219
Both fluoroalkylsilane (FAS) and octadecyltrimethoxysilane (ODS) were coated on oxidized silicon wafers using soaking and CVD method. Smooth coatings with Ra values of less than 1 nm were attained. The slope of the sliding acceleration against the inverse of the droplet mass showed an inflection point. That point shifted to the direction of smaller droplets with decreasing FAS ratio to ODS. The water droplets’ length was increased when the sliding velocity was increased. Fluoroalkylsilane addition to ODS increases the interaction between water and the hydrophobic surface. Results showed that the sliding acceleration of a water droplet depends strongly on the surface ratio of these silanes. 相似文献
995.
对《二维六角形晶格伊辛模型的重正化群解》一文的进一步计算 总被引:1,自引:1,他引:0
针对《二维六角形晶格伊辛模型的重正化群解》一文中有关〈V〉0的计算进行了修正,给出了新的重正化群的变换、重正化群的线性化变换矩阵以及临界指数. 相似文献
996.
Naofumi Ohtsu Masaoki Oku Kazuo Obara Shun Ito Toetsu Shisido Kazuaki Wagatsuma 《Surface and interface analysis : SIA》2007,39(6):528-532
Oxidation behavior of NiAl alloy at low temperatures was studied. A NiAl plate was oxidized by exposure to ambient atmosphere at room temperature, heated at 473 K in air, and heated at 773 K in air. The oxide formed on the NiAl surface was investigated by angle‐resolved X‐ray photoelectron spectroscopy (AR‐XPS). Chemical composition and atomic concentration in the oxide layer were analyzed with factor analysis of XPS spectra. Exposure of the NiAl plate to the ambient atmosphere resulted in the formation of an Al2O3 layer along with a small amount of NiO. Oxidation of the NiAl plate at 473 K in air formed a film of double‐layered oxide; the top layer consisted of NiAl2O4 and a small amount of NiO, and the second layer was Al2O3. Successive oxidation at 773 K only changed the oxide‐layer thickness without changing the structure. Formation of oxide observed in the present study corresponds to the thermodynamic prediction for the oxidation behavior of NiAl at 1373 K. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
997.
This article describes our ongoing efforts to understand dynamical processes such as rotational diffusion and photoisomerization
in polymorphic environments of a block copolymer. The objective is to explore how the typical properties of a block copolymer
solution such as critical micelle temperature (CMT) and temperature-induced sol-gel transition influence the rotational diffusion
of hydrophobic solute molecules. Rotational diffusion of solute molecules differs significantly below and above the CMT of
a block copolymer solution, while there is no influence of sol-gel transition on solute rotation. This is rationalized on
the basis of the site of solubilization of the solute molecules which is the palisade layer of the micelles in both phases
and unaffected by gelation. A similar result has been obtained in case of photoisomerization studies carried out with a carbocyanine
derivative in the sol and gel phases of the block copolymer. The isomerization studies have been extended to the reverse phases
(sol and gel phases) of the block copolymer to explore the nature of the water present in the cores of the reverse micelles.
Our results provide evidence for the existence of water droplets with properties resembling bulk water. In essence, we show
that despite having vastly differing bulk properties, both the solution and gel phases (normal as well as reverse) offer identical
microscopic environment. 相似文献
998.
R. P. Tye R. L. Gardner A. Maesono 《Journal of Thermal Analysis and Calorimetry》1993,40(3):1009-1016
Several factors in temperature measurement that can affect the precision of melting points and phase-change phenomena are discussed. In many cases, critical errors may arise in the measurement and control of temperatures due to incorrect placement and/or interpretation of the output of temperature sensors in the various system types that are in current use. Advantages can be obtained by using one temperature sensor only for temperature measurement and temperature control in a low mass infrared gold image fumace for the analytical studies in both the constant rate and stepwise isothermal thermoanalytical heating and cooling modes. Illustrations of the use of this instrumentation for measurements in both modes are given. 相似文献
999.
To FEM explicit algorithms for structural large-scale deformation impact responses, algorithm stability is discussed in the present paper. Algorithm stability is thought to include two aspects: One is called difference pattern stability and the other is called mesh stability. A self-adaptive adjusting method is proposed to ensure mesh stability with little amount of computation increased. 相似文献
1000.
V. I. Bykov T. P. Pushkareva S. I. Fadeev 《Reaction Kinetics and Catalysis Letters》1996,57(1):133-140
The influence of active sites number on the stationary characteristics of kinetic models is analyzed for some nonlinear schemes of conversion on catalyst surface. Mechanisms involving one and two types of active sites are considered. A possibility of critical effects is shown. 相似文献