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71.
Juan I. Rodríguez 《Journal of computational chemistry》2013,34(8):681-686
An efficient method for computing the quantum theory of atoms in molecules (QTAIM) topology of the electron density (or other scalar field) is presented. A modified Newton–Raphson algorithm was implemented for finding the critical points (CP) of the electron density. Bond paths were constructed with the second‐order Runge–Kutta method. Vectorization of the present algorithm makes it to scale linearly with the system size. The parallel efficiency decreases with the number of processors (from 70% to 50%) with an average of 54%. The accuracy and performance of the method are demonstrated by computing the QTAIM topology of the electron density of a series of representative molecules. Our results show that our algorithm might allow to apply QTAIM analysis to large systems (carbon nanotubes, polymers, fullerenes) considered unreachable until now. © 2012 Wiley Periodicals, Inc. 相似文献
72.
73.
Analysis of electron energy distribution function in a magnetically filtered complex plasma 下载免费PDF全文
The electron energy distribution function (EEDF) for a magnetically filtered dusty plasma is studied in a dusty double plasma device where the electron energy can be varied from 0.15 eV to ~ 2.8 eV and plasma density from 10 6 cm-3 to 10 9cm-3 . The characteristics of EEDF for these ranges of plasma parameters are investigated in a pristine plasma as well as in a dusty plasma. The results show that in the presence of dust, there is a drastic modification in EEDF patterns in a plasma with higher electron temperature and density than those in a low temperature and low density plasma produced by the magnetic filter. 相似文献
74.
《Physics and Chemistry of Liquids》2012,50(6):819-821
The recent study of He and You [P.-S. He and W.-L. You, Int. J. Mod. Phys. B26, 1250107 (2012)] on the relation between superfluid and condensate densities in a two-dimensional weakly interacting Boson system assumed a δ(x???x′) interaction between two particles at sites x and x′. The main purpose of this article is to point out the sensitivity of the conclusions of He and You to the choice of interaction. Thus, it is known for logarithmic interactions that one can have superfluidity without a condensate. Finally, some related ideas are mentioned in relation to superfluidity in liquid 4 He at exceedingly low temperatures. 相似文献
75.
《合成通讯》2012,42(24):3510-3527
AbstractA series of novel indoline-(thio)urea were designed and prepared using indoline(s) as a new platform and tested as organocatalysts in the Michael and Morita–Baylis–Hillman reactions. Most of the compounds were found to be very active catalysts although they did not promote the enantioselectivity. As agents for the conversion of thiocarbonyl compounds into carbonyl compounds, potentials of PIFA and DDQ were also displayed. Furthermore, DFT calculations rationalized the experimentally observed non-enantioselectivity of the catalysts. 相似文献
76.
《Journal of Coordination Chemistry》2012,65(19):3492-3501
Four MnIII-porphyrin complexes, chloro(tetraphenylporphinato)MnIII(1,6-diaminohexane), bromo(tetraphenylporphinato)MnIII(1,6-diaminohexane), azido(tetraphenylporphinato)MnIII(1,6-diaminohexane), and thiocyanato(tetraphenylporphinato)MnIII(1,6-diaminohexane), have been synthesized. These complexes have been characterized using UV-Vis, IR, ESI-mass spectra, elemental analyses, magnetic susceptibility measurements, and conductivity measurement. The molar conductance values of these complexes in ethanol indicate non-electrolytes. The utility of these complexes in de-polymerization of coal using humic acid as the coal model has been tested by the optical density method. 相似文献
77.
R. Gorges E. Prenner G. M. Kostner F. Paltauf A. Hermetter 《Journal of fluorescence》1994,4(4):367-368
The nonhydrolyzable fluorescent diether analog of phosphatidylcholine, 1-O-hexadecyl-2-0-pyrenedecyl-sn-glycero-3-phosphocholine, has been synthesized as a stable probe for the determination of phospholipid transfer to different lipoprotein classes with potential phospholipase activities. After incubation of total human serum with the new probe at 37°C for 3 hours a characteristic partition equilibrium between the main lipoprotein fractions was observed. The fluorescent lipid was not degraded under these conditions and, therefore, served as a marker for choline glycerophospholipid distribution between and transport to serum lipoproteins. 相似文献
78.
本文研究了MgB4O7中Ce^3+,Mn^2+光致发光性质与浓度的关系,并讨论了Ce^3+→Mn^2+能量传递的机理。 相似文献
79.
80.