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81.
Herbert JM Jacobson LD Lao KU Rohrdanz MA 《Physical chemistry chemical physics : PCCP》2012,14(21):7679-7699
A method that we have recently introduced for rapid computation of intermolecular interaction energies is reformulated and subjected to further tests. The method employs monomer-based self-consistent field calculations with an electrostatic embedding designed to capture many-body polarization (the "XPol" procedure), augmented by pairwise symmetry-adapted perturbation theory (SAPT) to capture dispersion and exchange interactions along with any remaining induction effects. A rigorous derivation of the XPol+SAPT methodology is presented here, which demonstrates that the method is systematically improvable, and moreover introduces some additional intermolecular interactions as compared to the more heuristic derivation that was presented previously. Applications to various non-covalent complexes and clusters are presented, including geometry optimizations and one-dimensional potential energy scans. The performance of the XPol+SAPT methodology in its present form (based on second-order intermolecular perturbation theory and neglecting intramolecular electron correlation) is qualitatively acceptable across a wide variety of systems-and quantitatively quite good in certain cases-but the quality of the results is rather sensitive to the choice of one-particle basis set. Basis sets that work well for dispersion-bound systems offer less-than-optimal performance for clusters dominated by induction and electrostatic interactions, and vice versa. A compromise basis set is identified that affords good results for both induction and dispersion interactions, although this favorable performance ultimately relies on error cancellation, as in traditional low-order SAPT. Suggestions for future improvements to the methodology are discussed. 相似文献
82.
83.
以3-三氯锗丙酸和正硅酸乙酯为原料,通过水解、缩聚凝胶热处理及氢气反应,在SiO2凝胶玻璃中析出立方相Ge纳米晶,当x=30时,凝胶玻璃中除了析出立方相Ge纳米晶处,还析出六方相GeO2,利用XRD测试了Ge纳米晶的大小,发现随着掺杂量的增加,纳米颗粒粒径从1nm增大到10nm,电子衍射表明镶嵌在SiO2凝交玻璃中的Ge纳米晶为多晶结构。 相似文献
84.
This paper is concerned with the uniqueness and L1 continuous dependence of entropy solutions for nonlinear hyperbolic systems of conservation laws. We study first a class of linear hyperbolic systems with discontinuous coefficients: Each propagating shock wave may be a Lax shock, or a slow or fast undercompressive shock, or else a rarefaction shock. We establish a result of L1 continuous dependence upon initial data in the case where the system does not contain rarefaction shocks. In the general case our estimate takes into account the total strength of rarefaction shocks. In the proof, a new time-decreasing, weighted L1 functional is obtained via a step-by-step algorithm. To treat nonlinear systems, we introduce the concept of admissible averaging matrices which are shown to exist for solutions with small amplitude of genuinely nonlinear systems. Interestingly, for many systems of continuum mechanics, they also exist for solutions with arbitrary large amplitude. The key point is that an admissible averaging matrix does not exhibit rarefaction shocks. As a consequence, the L1 continuous dependence estimate for linear systems can be extended to nonlinear hyperbolic systems using a wave-front tracking technique. 相似文献
85.
Summary The enantiomeric separation of nineteen biphenyl dimethyl dicarboxylate derivatives has been examined by HPLC on a chiral
statonary phase prepared by coating aminopropylated silica gel with cellulose tris-(3,5-dimethylphenylcarbamate). It was found
that trifluoroacetic acid (TFA) has a dominant effect on chiral separation for acidic compounds. The percentage of 2-propanol
in the mobile phase does not have a large effect on the anantioselectivity but the separation was dramatically influenced
by the kind of alcohol in the mobile phase. The effect of temperature on the chiral separation is also discussed. Most of
the enantiomers investigated could be resolved satisfactorily. 相似文献
86.
Jiaxin Tian Yan Chen Dr. Marie Vayer Alexandre Djurovic Régis Guillot Dr. Refka Guermazi Dr. Samuel Dagorne Dr. Christophe Bour Prof. Vincent Gandon 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(56):12831-12838
The catalytic activity of cationic NHC-ZnII and NHC-AlIII (NHC=N-heterocyclic carbene) complexes in reactions that require the electrophilic activation of soft C−C π bonds has been studied. The former proved able to act as a soft π-Lewis acid in a variety of transformations. The benefit of the bulky IPr NHC ligand was demonstrated by comparison with simple ZnX2 salts. The tested NHC-AlIII catalyst is not able to activate C−C π bonds but simple AlX2+ ions were found potent in some cases. 相似文献
87.
Optical Review - For improving the performance of vibration discrimination in terms of dual Mach–Zehnder interferometric (DMZI) perimeter system, we proposed a novel method based upon the... 相似文献
88.
Cheng Jiaxin Yang Haitao Fan Chuanlin Li Rongxing Yu Xiaohua Li Hongtao 《Journal of Solid State Electrochemistry》2020,24(10):2199-2217
Journal of Solid State Electrochemistry - Fluidized bed electrodes (FBEs), which were discovered in the late 1960s, are 3D (three-dimensional) particle electrodes. The FBEs have been attracting... 相似文献
89.
Chen Yue Peng Xihong Fan Xinyue Yu Qing Zhao Guiying Lin Yingbin Li Jiaxin Huang Zhigao 《Journal of Solid State Electrochemistry》2019,23(2):367-377
Journal of Solid State Electrochemistry - A big challenge in the high-performance transition metal oxide anode for lithium-ion batteries (LIBs) is relieving the volume changes during the... 相似文献
90.
胡家信 《数学物理学报(B辑英文版)》1996,(2)
AKINETICAPPROACHTOSCALARMULTI-DIMENSIONALCONSERVATIONLAWS¥HaJiaxin(胡家信)(YoungScientistsLaboratoryofWuhanInst.ofMath.Sci.,Acad... 相似文献