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1.
Journal of Thermal Analysis and Calorimetry - The work concerns the alumina–graphene materials sintered by two different pressure methods. The different particle sizes of graphene were used....  相似文献   
2.
We consider the fixed point property (FPP) in an ordered set of width two (every antichain contains at most two elements). The necessary condition of the FPP and a number of equivalent conditions to the FPP in such sets is established. The product theorem is proved, as well.  相似文献   
3.
It is shown that the Galerkin-Petrov method if applied in a controlled way yields reliable results for excited states of the same symmetry classifications as the ground state. Computations are performed for the 21 S and 31 S states of He. The problem of optimizing nonlinear parameters of the basis functions by means of the GP method is discussed. A special optimization scheme is suggested and numerically illustrated for someS states of He.  相似文献   
4.
FTIR spectra of mixtures of fluoroform (F3CH) and ammonia (NH3), have been studied in liquid xenon between 5400 and 500 cm-1. Spectroscopic evidence for the formation of a hydrogen bonded complex has been found and the complexation enthalpy Delta(LXe)H degrees in the temperature interval between 173 and 215 K, was determined to be 14.4 (7) kJ mol-1. The parallel fundamentals nu1 and nu2 of ammonia reveal a strong narrowing effect upon complex formation, whereas the perpendicular fundamentals nu3 and nu4 show a modest decrease of their width. CP corrected ab initio calculations at the MP2(FULL)/6-311++G(3df,2pd) level predict a linear geometry for the complex, characterized by a small red shift of the CH stretch frequency of fluoroform. The ab initio interaction energy was found to be compatible with the isolated molecule complexation energy extrapolated from the experimental Delta(LXe)H degrees .  相似文献   
5.
Summary The virial theorem for a molecule in the relativistic clamped-nuclei approximation is derived. The individual energy contributionsA (momentum energy),B (mass energy),T=A+B (kinetic energy) andV (potential energy) are expressed in terms ofE, E/R (derivate w.r.t. the nuclear coordinates) and the relativistic correction E/2 (derivative w.r.t. Sommerfield's fine-structure constant ). IfE and E/R are known as functions of , then all individual energy terms are also known as functions of . As an example, numerical results for H 2 + are presented. The relativistic and nonrelativistic potential energy curves and the paradoxical behavior of their different contributions are analyzed and interpreted in both the largeR and shortR ranges.Dedicated to Professor W. Kutzelnigg on the occasion of his 60th birthday  相似文献   
6.
Summary The recently developed relativistic double perturbation theory is extended to handle relativistic changes of molecular structure more easily. This is achieved by simple coordinate scalings. Accurate higher order mixed perturbation energies for H 2 + are calculated. The relativistic changes of bond energy,DE, of bond length,R e , and especially of force constant,k, and of anharmonicity,a, are large, up to 100%·(Z/c)2. The dominant contributions tok anda are due to the indirect change of the nonrelativistick anda connected with the relativistic change of bond length. Accordingly the relativistic changes obey Badger's and Gordy's rules (–RDEk).Dedicated to Prof. Klaus Ruedenberg in appreciation of his fundamental contributions to both formal theory and physical explanations in quantum chemistry  相似文献   
7.
The performance of dual waveband HgCdTe photodiodes fabricated using metaloorganic chemical vapour deposition operated at high temperatures is presented. The effect of additional separating layer on the quantum efficiency and cross-talk of the photodiodes is analyzed. The photodiodes with cutoff wavelengths up to 6 μm, good R0A product, and high quantum efficiency at 200 K have been demonstrated. The temperature dependence of the differential resistance is discussed. It is shown that the multilayer heterojunction P-n-N-n-P structure operating in a simultaneous mode has better performance than a structure operating in a sequential mode.  相似文献   
8.
Coal derived oil was hydroprocessed over Ni–Mo and Ni–Co–Mo catalysts in a continuous flow laboratory unit. The effect of the reactor mode (down-flow or up-flow) and of the hydrogen circulation on the efficiency of hydrogenation were investigated in one and two reactors systems.
, , - Ni–Mo Ni–Co–Mo . ( ) - , - .
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10.
We examine the connections between a novel class of multi-person stopping games with redistribution of payoffs and multi-dimensional reflected BSDEs in discrete- and continuous-time frameworks. Our goal is to provide an essential extension of classic results for two-player stopping games (Dynkin games) to the multi-player framework. We show the link between certain multi-period mm-player stopping games and a new kind of mm-dimensional reflected BSDEs. The existence and uniqueness of a solution to continuous-time reflected BSDEs are established. Continuous-time redistribution games are constructed with the help of reflected BSDEs and a characterization of the value of such stopping games is provided.  相似文献   
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