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941.
The main purpose of the present paper is to derive some properties associated with the neighborhoods and partial sums of a certain class of meromorphic multivalent functions.  相似文献   
942.
In this paper, firstly we present a connection between determinants of tridiagonal matrices and the Lucas sequence. Secondly, we obtain the complex factorization of Lucas sequence by considering how the Lucas sequence can be connected to Chebyshev polynomials by determinants of a sequence of matrices.  相似文献   
943.
In this article, the influence of time discreteness on the transition coefficients is investigated within the framework of time fractional development of quantum systems which has been developed recently by the present authors [22]. In this formalism, fractional mathematics which is a powerful tool to study the non-Markovian and non-Gaussian properties of physical processes is used in order to obtain time fractional evolution operator and transition probability. They are given in terms of Mittag–Leffler function which plays an important role in the mathematical structure as well as the physical interpretation of the phenomena under investigation. In order to place the presented formalism on a concrete basis, historical Stern–Gerlach experiment has been revisited with the purpose of studying transition coefficients which have a non-Markovian feature. The effect of the time fractionalization has been clearly illustrated in the figures via fractional derivative order α.  相似文献   
944.
Summary Hydrous zirconium dioxide was prepared to study the sorption behavior and the removal of strontium from radioactive waste solutions. The hydrous zirconium dioxide were identified and characterized. The parameters affecting the strontium adsorption were investigated. Sorption data have been interpreted in terms of Langmuir equations. Thermodynamic parameters for the sorption system have been determined at 303, 313, 323 and 333 K temperatures. The values ofDH°=102.30 kJ/mol andDG°=-26.03 kJ/mol at 313 K prove that the sorption of strontium on hydrous zirconium oxide is an endothermic and a spontaneous process.  相似文献   
945.
Micellar properties of dodecylpyridinium chloride (DPC) were investigated by means of electrical conductometry with emphasis on the influences of cosolvent-water content and temperature. Ethanol was used as a cosolvent. Conductivity measurements gave information about critical micelle concentration and micellar ionization degree of the water-ethanol micellar solutions at different temperatures. In all solvent mixtures, it was observed that the critical micelle concentration of DPC and the degree of the counterion dissociation increase with an increasing concentration of ethanol and increasing temperature. Micellar and thermodynamics data were obtained from the temperature dependence of critical micelle concentrations in various aqueous mixtures of ethanol. In order to explain the effect of the cosolvent, the differences in the Gibbs energies of micellization of DPC between water and binary cosolvent were determined. The standard free energy (ΔG°mic) of micellization was found to be negative as the concentration of the solvent increases, but it is roughly independent of temperature. Although the enthalpic contribution was found to be larger than the entropic one, in particular at lower temperatures, an entropy-enthalpy compensation effect was observed for all systems. Also, enthalpy (ΔH°mic) and entropy (ΔS°mic) of micellization are strongly temperature dependent and decrease with increasing temperature and cosolvent content. The text was submitted by the authors in English.  相似文献   
946.
Hydrogen-bonded helical organic nanotubes   总被引:1,自引:0,他引:1  
  相似文献   
947.
It is proved that if A 1,A 2,..., A m and B 1,B 2,..., B n are objects in a finitely accessible additive category \(\mathcal{A}\) such that their pure injective envelopes are indecomposable, and there are pure monomorphisms μ:A 1?⊕?A 2?⊕?...?⊕?A m B 1?⊕?B 2?⊕?...?⊕?B n and ν:B 1?⊕?B 2?⊕?...?⊕?B n A 1?⊕?A 2?⊕?...?⊕?A m , then m?=?n and there are a permutation σ and pure monomorphisms A i B σ(i) and B σ(i)A i for every i?=?1, 2, ..., n.  相似文献   
948.
Although graphite and hexagonal form of BN (h-BN) are isoelectronic and have very similar lattice structures, it has been very difficult to intercalate h-BN while there are hundreds of intercalation compounds of graphite. We have done a comparative first principles investigation of lithium intercalation of graphite and hexagonal boron nitride to provide clues for the difficulty of h-BN intercalation. In particular lattice structure, cohesive energy, formation enthalpy, charge transfer and electronic structure of both intercalation compounds are calculated in the density functional theory framework with local density approximation to the exchange-correlation energy. The calculated formation enthalpy of the considered forms of Li intercalated h-BN is found to be positive which rules out h-BN intercalation without externally supplied energy. Also, the Li(BN)3 form of Li-intercalated h-BN is found to have a large electronic density of states at the Fermi level and an interlayer state that crosses Fermi level at the zone center; these properties make it an interesting material to investigate the role of interlayer states in the superconductivity of alkali intercalated layered structures. The most pronounced change in the charge distribution of the intercalated compounds is found to be charge transfer from the planar σ states to the π states.  相似文献   
949.
We investigate the optical response of an atomic Bose-Einstein condensate with a vortex lattice. We find that it is possible for the vortex lattice to act as a photonic crystal and create photonic band gaps, by enhancing the refractive index of the condensate via a quantum coherent scheme. If high enough index contrast between the vortex core and the atomic sample is achieved, a photonic band gap arises depending on the healing length and the lattice spacing. A wide range of experimentally accessible parameters are examined and band gaps in the visible region of the electromagnetic spectrum are found. We also show how directional band gaps can be used to directly measure the rotation frequency of the condensate.  相似文献   
950.
Periodica Mathematica Hungarica - Since the introduction of Bernstein operators, many authors defined and/or studied Bernstein type operators and their generalizations, among them are Morigi and...  相似文献   
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