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1.
令Ω1与Ω2与C^n中的两个有界齐性域,假设φ:1Ω→Ω2是一个全纯映射。在本中,我们研究相应的复合算子Cφ:β(Ω2)→β(Ω1)的有界性和紧性,特别地,我们讨论取B^n和U^n的情形。 相似文献
2.
The spin-1 Ising model, which is equivalent to the three-component lattice gas model, is used to study wetting transitions in three-component surfactant systems consisting of an oil, water, and a nonionic surfactant. Phase equilibria, interfacial profiles, and interfacial tensions for three-phase equilibrium are determined in mean field approximation, for a wide range of temperature and interaction parameters. Surfactant interaction parameters are found to strongly influence interfacial tensions, reducing them in some cases to ultralow values. Interfacial tensions are used to determine whether the middle phase, rich in surfactant, wets or does not wet the interface between the oil-rich and water-rich phases. By varying temperature and interaction parameters, a wetting transition is located and found to be of the first order. Comparison is made with recent experimental results on wetting transitions in ternary surfactant systems.This paper is dedicated to J. K. Percus in honor of his 65th birthday. 相似文献
3.
Junchai Zhao Shichun Jiang Xiangling Ji Lijia An Bingzheng Jiang 《Journal of Polymer Science.Polymer Physics》2004,42(18):3496-3504
The surface morphologies of poly(styrene‐b‐4vinylpyridine) (PS‐b‐P4VP) diblock copolymer and homopolystyrene (hPS) binary blend thin films were investigated by atomic force microscopy as a function of total volume fraction of PS (?PS) in the mixture. It was found that when hPS was added into symmetric PS‐b‐P4VP diblock copolymers, the surface morphology of this diblock copolymer was changed to a certain degree. With ?PS increasing at first, hPS was solubilized into the corresponding domains of block copolymer and formed cylinders. Moreover, the more solubilized the hPS, the more cylinders exist. However, when the limit was reached, excessive hPS tended to separate from the domains independently instead of solubilizing into the corresponding domains any longer, that is, a macrophase separation occurred. A model describing transitions of these morphologies with an increase in ?PS is proposed. The effect of composition on the phase morphology of blend films when graphite is used as a substrate is also investigated. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3496–3504, 2004 相似文献
4.
3d-metal antimonides: Fe1+x Sb, N+x Sb, Co+x Sb and the (Ni1?y Fe y )Sb solid solution have been studied by the Mössbauer effect method at 57Fe and 119Sn. It was found that the quadrupole interactions at the Fe and Sn nucleus in 3d-metal antimonides are very sensitive to the filling of different crystallographic sites with metal atoms. The metal atoms in trigonal-bipyramidal sites have a strong effect on the quadrupole splitting of 119Sn. They are nearest to anions (Sb or Sn) with the typical axial ratio of c/a = 1.25. The QS(x) dependence of 119 Sn in 3d-metal antimonides in the 0 ≤ x ≤ 0.1 concentration range can be used to determine x – the concentration of transition metal excess relative to the stoichiometric composition. 相似文献
5.
This paper gives a critical review on the applications of ToF SIMS in the areas of polymer additive characterization and in the study of polymer blends and interfaces. Polymer additives can readily be identified by ToF SIMS using their parent molecular ions or characteristic fragments. This analytical capability has been successfully applied to monitor the migration or segregation of additives during polymer processing. ToF SIMS is an ideal analytical tool for the study of polymer blends and interfaces because it is able to provide information on both surface composition and morphology. In combination with other analytical techniques such as AFM and XPS, ToF SIMS chemical imaging capability has opened up new horizons in the investigation of complex polymer blend systems. Finally the main advantages and limitations of ToF SIMS in these application areas are also discussed. 相似文献
6.
We report on the lattice-mismatched growth of step-graded InxAl1−xAs buffer layers on GaAs (0 0 1) substrates by molecular beam epitay (MBE). The approach to growing highly lattice-mismatched epilayers is to interpose a buffer layer between the substrate and the active layer. Two samples G30 and G40 with active layer compositions, respectively, x = 0.46 and x = 0.41, are studied by photoluminescence (PL). At low temperature, the PL spectra show a large broadened band whose energy and intensity depend on the active layer composition. The step-graded layer compositions improved the crystalline quality of these structures and increase the active layer PL band intensity. 相似文献
7.
Elżbieta Godlewska M. Mitoraj F. Devred B. E. Nieuwenhuys 《Journal of Thermal Analysis and Calorimetry》2007,88(1):225-230
A Ti–45.9Al–8Nb
(at%) alloy with a lamellar structure (γ+α2)
was oxidised in air at 700, 800, 850 and 900°C in isothermal and thermal
cycling conditions. The reaction progress was followed by thermogravimetric
measurements. In isothermal conditions the oxidation kinetics followed approximately
a parabolic rate law and the rate constants ranged from about 10–12
kg2 m–4 s–1
at 700°C to 10–10 kg2
m–4 s–1
at 900°C. The oxide scales were built of Al2O3
and TiO2, the former being the main component of the
outermost layer. The oxidation behaviour of Ti–45.9Al–8Nb was
referred to a commercial titanium alloy, WT4 (Ti–6Al–1Mn), and
selected oxidation-resistant alloys. 相似文献
8.
利用η-Carleson测度给出了单位球上不同Privalov以及不同加权Bergman-Privalov空间之间的复合算子是度量有界或度量紧的充要条件,并给出了一些函数理论方面的刻画. 相似文献
9.
用射频磁控共溅射法制备了Cu体积分数分别为 10 % ,15 % ,2 0 %和 3 0 %的Cu MgF2 复合金属陶瓷薄膜 .用x射线衍射、x射线光电子能谱和变温四引线技术对薄膜的微结构、组分及电导特性进行了测试分析 .微结构分析表明 :制备的Cu MgF2 复合薄膜由fcc Cu晶态纳米微粒镶嵌于主要为非晶态的MgF2 陶瓷基体中构成 ,Cu晶粒的平均晶粒尺寸随组分增加从 11 9nm增至 17 8nm .5 0— 3 0 0K温度范围内的电导测试结果表明 :当Cu体积分数qM 由 15 %增加到 2 0 %时 ,Cu MgF2 复合薄膜的电阻减小了 8个量级 ,得出制备的复合薄膜渗透阈qCM 应处于 15 %和 2 0 %之间 .qM 在 10 %和 15 %之间的薄膜呈介质导电状态 ,而在 2 0 %和 3 0 %之间的薄膜则呈金属导电状态 .从理论上讨论了复合薄膜中杂质电导和本征电导的激活能及其对电导的贡献 ,并讨论了Cu MgF2 复合纳米金属陶瓷薄膜的渗透阈 ,得到了和实验一致的结果 相似文献
10.
L. G. Mezhlumyan Sh. Kh. Rakhimova P. Kh. Yuldashev N. K. Aikhodzhaeva M. A. Saidkhodzhaeva A. I. Massino S. Makhmudova 《Chemistry of Natural Compounds》2004,40(1):59-62
The glutelin fraction was used as the food value index of local corn. The base-soluble fraction was used as a test of the glassiness of local strains of rice grain. The content of gliadins and glutelins did not change over 24 h after wheat grain cultivated in Uzbekistan was moistened. 相似文献