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51.
Density functional theory calculations were carried out to investigate the electronic structures of Keggin-typed [XMo12O40]n− and [XW12O40]n− anions with different heteroatoms (X = Zn2+, B3+, Al3+, Ga3+, Si4+, Ge4+, P5+, As5+, and S6+). The influence of solvent on redox properties of heteropolyanions was discussed. For [XW12O40]n− systems two linear correlation: first, between the experimental redox potential and energies of LUMO orbital; and second, between the experimental redox potential and total energy interaction (calculated between internal tetrahedron (XO4n−), and rest of Kegging anion skeleton, (W12O36)) were designated. Taking into account the similarity of XW12O40n− and XMo12O40n− systems (in geometry and electronic structure), the estimated redox potential of molybdenum heteropolyanions (with X being p block elements) in different solvent were proposed. 相似文献
52.
《Physics letters. A》2020,384(24):126611
The characterization of quantum correlations is crucial to the development of new quantum technologies and to understand how dramatically quantum theory departs from classical physics. Here we systematically study single- and multiparticle interference patterns produced by general two- and three-qubit systems. From this we establish on phenomenological grounds a new type of quantum correlation for these systems, which we name quantum interference, deriving some quantifiers that are given explicitly in terms of the density matrix elements of the complete system. By using these quantifiers, we show that, contrary to our expectations, entanglement is not a required property for a composite quantum system to manifest multiparticle interference. 相似文献
53.
For any particular fluid, the set of three critical constants (CC) – pressure Pc, temperature Tc and molar volume Vc – has a central importance in defining the physical behaviour of the fluid in the gas and liquid states. However, little attention seems to have been paid in the past to the relations between the CC of different substances. In the present paper, some simple and apparently novel relations have been found between the three CC for the set of four noble gases: Ne, Ar, Kr, Xe. Defining the critical quotient Qc ≡ RTc/Pc (where R is the Gas Constant) the correlations may be summarised by the dual equation: (Vc/cm3 mol−1) = 27 + 0.31 (Tc/K) = 3.3 + 0.280 (Qc/cm3 mol−1), which describes the CC data for the quartet Ne–Xe with an average uncertainty of 0.5%. Regarding the other two noble gases, the two isotopes of the lightest member, 3He and 4He, show the deviations from these relations that are expected from quantal effects and their low molar masses; while for the heaviest member, Rn, the correlations enable a value of 145(5) cm3 mol−1 to be estimated for Vc that is not otherwise well defined in the literature. By contrast, and contrary to the general assumption, the second lightest member, Ne, apparently does not show appreciable quantal effects in the area, so that Ne–Xe may be considered together as a group. These correlations are compared with the behaviour of a selection of polyatomic fluids; in these comparisons, the NG dual correlation equation provides a reference line defining the presumed simplest behaviour. This and related areas show a “Residual Volume Effect”, in that extrapolating the equivalent temperature and energy parameters to zero for the state of zero-mass point particles, referred to here as the hypothetical element zeronium (Ze), the system in each case still has a finite intercept; this intercept amounts to essentially 34% of the average volume for the present quartet Ne–Xe, rather than the zero volume expected for this condition. 相似文献
54.
在前人工作的基础上,建立了非牛顿幂律流体有界双重介质试井模型.根据模型的特点,提出了相应的特征值问题,求出了特征值和特征函数.定义了油层压力关于空间变量的正交积分变换.根据特征函数系的完备正交性和矩阵微分方程理论,获得了油层压力分布以及井底压力,压力导数的实空间解析解(无穷级数形式).首次直接根据实空间解析解绘制了样版曲线,并在同一张双对数坐标纸上描出拉普拉斯方法制作的样版曲线,同时给出二者间的误差走势图.通过对比分析发现,随着级数项数的增大,根据解析解制作的样版曲线逐渐逼近拉普拉斯方法制作的样版曲线.新疆油田实例证实了该方法的有效性.研究结果进一步补充,完善了试井分析理论. 相似文献
55.
Anatoly S. Chirkin Mikhail Yu. Saigin Ivan V. Shutov 《Journal of Russian Laser Research》2008,29(4):336-346
We show that parametric amplification at low-frequency pumping can be implemented in aperiodic nonlinear photonic crystals.
In this process, the intensities of the waves with frequencies higher than the pumping frequency increase with increase in
the interaction length as in the case of the standard process of parametric amplification at high-frequency pumping. The process
under consideration includes a nondegenerate parametric down-conversion followed by two parametric up-conversions in the same
pumping wave. As a result, generation at four new frequencies arises. Quantum analysis of the process demonstrates the presence
of entanglement in the states of four modes.
Talk presented at the oral issue of J. Russ. Laser Res. dedicated to the memory of Professor Vladimir A. Isakov, Professor
Alexander S. Shumovsky, and Professor Andrei V. Vinogradov held in Moscow February 21–22, 2008. 相似文献
56.
Optical solitary waves that propagate in a Kerr medium exhibiting a power-law nonlocal response are studied analytically. The first-principles stability analysis based on quantum field theory shows that within the whole range of the exponent (the fractal dimension) the solitary wave can be stabilized. 相似文献
57.
M. Pârlog G. Tăbăcaru J. P. Wieleczko J. D. Frankland B. Borderie A. Chbihi M. Colonna M. F. Rivet 《The European Physical Journal A - Hadrons and Nuclei》2005,25(2):223-228
Stochastic mean-field simulations for multifragmenting sources at the same excitation energy per nucleon have been performed. The freeze-out volume, a concept which needs to be precisely defined in this dynamical approach, was shown to increase as a function of three parameters: freeze-out instant, fragment multiplicity and system size. 相似文献
58.
We have studied the properties of the relativistic helium fragments emitted from the projectile in the interactions of 24Mg ions accelerated at an energy of 3.7 A GeV with emulsion nuclei. The total, partial nuclear cross-sections and production rates of helium fragmentation channels in relativistic nucleus-nucleus collisions and their dependence on the mass and energy of the incident projectile nucleus are investigated. The yields of multiple helium projectile fragments disrupted from the interactions of 24Mg projectile nuclei with hydrogen H, light CNO and heavy AgBr groups of target emulsion nuclei are discussed and they indicate that the breakup mechanism of the projectile seems to be independent of the target mass. Limiting fragmentation behavior of fast-moving helium fragments is observed in both the projectile and target nuclei. The multiplicity distributions of helium projectile fragments emitted in the interactions of 24Mg projectile nuclei with the different target nuclei of the emulsion are well described by the KNO scaling presentation. The mean multiplicities of the different charged secondary particles, normally defined shower, grey and black ( ns, ng and nb) emitted in the interactions of 3.7 A GeV 24Mg with the different groups of emulsion nuclei at different ranges of projectile fragments are decreasing when the number of He fragments stripped from projectile increases. These values of ni ( i = s, g, b and h particles) in the events where the emission of fast helium fragments were accompanied by heavy fragments having Z 3 seem to be constant as the He multiplicity increases, and exhibit a behavior independent of the He multiplicity. 相似文献
59.
Vé ronique Maume-Deschamps 《Transactions of the American Mathematical Society》2001,353(8):3371-3389
We study the decay of correlations for towers. Using Birkhoff's projective metrics, we obtain a rate of mixing of the form:
where goes to zero in a way related to the asymptotic mass of upper floors, is some Lipschitz norm and is some norm. The fact that the dependence on is given by an norm is useful to study asymptotic laws of successive entrance times.
60.
Based on the 1/n-expansion derived in a previous paper, the displacement fluctuations are analyzed in a quantum n-vector model of anharmonic crystal in the large n regime. It is shown that in the ferroelectric phase the n limit of the local fluctuation field has faster large-distance correlation decay than its Hartree–Fock approximation. Also, the critical exponent of the global displacement fluctuation is strictly smaller there than the Hartree–Fock exponent. In particular, the displacement fluctuations may be normal in the ferroelectric phase in spite of the Hartree–Fock prediction. 相似文献