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181.
We present a new model to analyze dielectric spectroscopy measurements on charged lamellar systems, with the following improvements with respect to the hitherto available models: (i) it does not rely on the hypothesis of local electro-neutrality, and allows to treat the salt-free case; (ii) the chemical exchange governing the partition between free and bound ions is properly taken into account; (iii) a fully analytical solution is provided. The variation of the frequency-dependent dielectric permittivity with both thermodynamic and kinetic characteristics of the free-bound ion equilibrium is presented. In particular, the relative weights of both relaxation modes (exchange and transport), and their characteristic frequencies are discussed. This study opens the way to the analysis of systems for which the usual models are irrelevant, such as salt-free clay gels or membranes. 相似文献
182.
Che Ming Ko 《Physics letters. [Part B]》1983,120(4-6):294-296
We show that an important contribution to subthreshold K− production in high energy heavy ion collision is the strangeness exchange reactions Yπ→K---N between the hyperons and pions initially produced in the collision. Estimates are given for the number of K− produced via this mechanism and it accounts for a large fraction of the experimental observation. 相似文献
183.
Results are presented of measurements made of alternating current susceptibility changes Δχ = χB - χ0 induced by external application of a constant magnetic field using the beat method (f ~ 1MHz). For 1 K < (T ? Tc) < 50 K and taking the appropriate values of magnetic fields the relation Δχ ~ B2 was satisfied. Making use of the Debye theory adapted for the non-linear dielectric effect, it was shown that the mean number n of elementary cells in a cluster varies with temperature according to the relation n ~ (T ? Tc)-1.31. 相似文献
184.
Li Feng Zhang Hongyun Che Deji Chen Dongli Xue H. Rong Zhang Hongquan 《Transition Metal Chemistry》1994,19(1):1-3
Summary Acetylferrocenyl-3-hydroxyl-2-naphthoylhydrazone and its transition metal coordination compounds were prepared. The composition and properties of the ligand and the nature of metal to ligand bonding in its coordination compounds were characterized by elemental analyses, i.r. spectra, n.m.r. spectra, u.v.-vis. spectra, thermal analyses and molar conductivities. 相似文献
185.
Singlet oxygen (^1O2) is widely considered to play a major role in photodynamic therapy (PDT), and thus an increasing attention has been focused on the direct detection of ^1O2 near-infrared luminescence around 1270 nm for PDT dosimetry. A new sensitive detection system is developed to directly measure the temporal and spectral resolved ^1O2 luminescence spectra. The triplet state and ^1O2 lifetimes of Rose Bengal as a model photosensitizer in different solvents are determined, and the obtained results agree well with the published data. Our detection system has the potential application in ^1O2 luminescence-based PDT dosimetry. 相似文献
186.
187.
Self-assembly of positively charged and charge-neutral tridentate cyclometalated platinum(II) complexes leads to nanowires and the drop-cast film containing these nanowires behaves as a n-type semiconductor. 相似文献
188.
在对人本主义学习理论做简要阐述的基础上,结合物理学的学科性质,就人本主义学习观如何应用到物理教学上做了些尝试. 相似文献
189.
The main propose of this paper is devoted to studying the solvability of the generalized order tensor complementarity problem. We define two problems: the generalized order tensor complementarity problem and the vertical tensor complementarity problem and show that the former is equivalent to the latter. Using the degree theory, we present a comprehensive analysis of existence, uniqueness and stability of the solution set of a given generalized order tensor complementarity problem. 相似文献
190.
Zhongyuan Che 《Czechoslovak Mathematical Journal》2010,60(2):489-494
We give a necessary and sufficient condition for the existence of perfect matchings in a plane bipartite graph in terms of
elementary edge-cut, which extends the result for the existence of perfect matchings in a hexagonal system given in the paper
of F. Zhang, R. Chen and X. Guo (1985). 相似文献