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981.
We present the classical solution of Lagrange equations for the black hole with a global monopole or with a cosmic string. Then we obtain the wavefunction of the space-time by solving the Wheeler-De Witt equation. De Broglie-Bohm interpretation applied to the wavefunction gives the quantum solution of the space-time. In the end, the quantum effect on Hawking radiation is studied. 相似文献
982.
通过测定在纯水和CdCl2溶液亚相上十八胺单分子膜的平衡、循环π~A等温线及其动态弹性,发现在亚相中加入Cd2+可以使膜的液态相凝聚性增强,固态相凝聚性减弱.液态的单分子膜在两种亚相上有较好的可回复性,而在固态膜中则不然.这可归因于在水面上十八胺分子间可形成氢键,而在CdCl2水溶液亚相上的十八胺则与Cd2+发生配位,形成了多配位络合物,两种情况下十八胺分子在高膜压区都会发生稳定的聚集.静、动态弹性的比较表明,膜障的振动不利于十八胺分子与Cd2+间的配位作用. 相似文献
983.
Ying Ling Liu Yuan Ling Liu Ru Jong Jeng Yie-Shun Chiu 《Journal of polymer science. Part A, Polymer chemistry》2001,39(10):1716-1725
A novel phosphorus-containing bismaleimide, 3,3′-bis(maleimidophenyl)phenylphosphine oxide (BMPPPO), was synthesized from triphenylphosphine oxide. This bismaleimide exhibited good solubility in common organic solvents, such as methylethylketone, methylisobutylketone, dichloromethane, chloroform, tetrahydrofuran, acetone, methanol, ethanol, and hot toluene. A low melting point (Tm = 148 °C), a relatively low polymerization temperature (Tp = 214 °C), and a wide processing window (Tp − Tm = 66 °C) were also obtained for BMPPPO. This implies better processing capability. In contrast to most known phosphorus-containing polymers, the incorporation of BMPPPO into poly(bismaleimide) enhanced the polymer glass-transition temperature. Thermal stability at temperatures over 550 °C and char yields in the high-temperature region over 700 °C were also improved. As a result, the flame-retardant properties of the poly(bismaleimide)s were improved. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1716–1725, 2001 相似文献
984.
O. Pietraszkiewicz M. Pietraszkiewicz H. Radecka J. Radecki 《Journal of inclusion phenomena and macrocyclic chemistry》2001,41(1-4):129-134
Lipophilic polyamines 1 and 2 form stable monolayers at the air–water interface. The shapes of the isotherms show a strong pH-dependence due to different stages of polyamine protonation. For all isomers of dihydroxybenzene the strong interaction with 1 and 2 can be observed at pH 4, 6, and 8. Polyamines 1and 2 in the PVC liquid membrane act as the sensory element of the potentiometric sensor for selective determination of catechol in the presence of other isomers of dihydroxybenzenes. 相似文献
985.
Chi-Ming Yam Liu Zheng Michle Salmain Claire-Marie Pradier Philippe Marcus Grard Jaouen 《Colloids and surfaces. B, Biointerfaces》2001,21(4)
We compare herein the interfacial reactivity of self-assembled monolayers (SAMs) of 11-mercaptoundecanoic acid (MUA), 1-undecanethiol (UDT) and 11-mercaptoundecanol (MUD) on gold surfaces towards aqueous solutions of poly-(
-lysine) (PL). Liquid-phase labelling of PL with the alkyne dicobalt hexacarbonyl cluster 1 combined with analysis of the substrates by Fourier transform infrared reflection–absorption spectroscopy (FT-IRRAS) and X-ray photoelectron spectroscopy (XPS) revealed that irreversible binding of PL occurred in all cases. However, the mechanism of binding involved differed markedly from one monolayer to the other. The main mode of interaction of PL to MUA SAM was of electrostatic nature between the terminal carboxylate of MUA and the ammonium groups of PL. For a similar number of bound thiolate molecules, the UDT adsorbed layer was found less continuous than the MUA one, allowing a higher fraction of PL to directly bind to the gold surface. As for MUD, very little thiolate molecules were adsorbed, leaving bare gold surface areas for non specific adsorption of PL. 相似文献
986.
987.
988.
使用接触角、原子力显微镜(AFM)、静电力显微镜(EFM)和傅里叶变换红外(FTIR)光谱对辛基三乙氧基硅烷(C8TES)/十八烷基三氯硅烷(OTS)均相混合自组装单分子膜(SAM)及其形成过程中样品表面的润湿性、表面形貌、表面电势和膜内分子的有序度进行了表征,对采用分步法利用C8TES分子空间位阻制备C8TES/OTS均相混合SAM的反应机制进行了研究. 结果表明,C8TES/OTS均相混合SAM表面接触角为105°,样品表面平整、光滑;对样品表面电势进行分析后发现,混合SAM表面电势分布均匀,电势频率分布为典型的正态分布;在均相混合SAM的形成过程中,样品表面电势的分布始终十分均匀,电势频率分布均为典型的正态分布;C8TES/OTS均相混合SAM是一种具有上下两层分子排列密度不同的膜结构的单分子膜,其内部结构至少在500 nm×500 nm到20 μm×20 μm尺度上是高度均匀一致的,膜内没有明显的特征结构,具有典型的均相混合SAM特征. 相似文献
989.
990.
Qing L? Ming Hua LIU* Laboratory of Colloid Interface Science Center for Molecular Science Institute of Chemistry Chinese Academy of Sciences 《中国化学快报》2001,(12)
Langmuir monolayer at the air/water interface is the basis to understand the molecular arrangement and to fabricate the organized molecular films1. Bolaamphiphiles describes the molecules in which two head functional groups are linked by one or two hydrophobic chains2,3. In comparison with the one-headed amphiphile, abundant configurations of Langmuir monolayer are expected in bolaamphiphiles. Generally, three kinds of configurations of the Langmuir monolayers of bolaamphiphile at the air/w… 相似文献