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61.
The DFT-B3LYP and G3X model chemistry were used to predict the cation structures and energetics of fluorinated, chlorinated,
and brominated methanes. Ion–complex structures between methylene cations and HX (X = F, Cl, Br) were found for all H-containing
cations, and [CHF–FH]+, [CF2–FH]+, [CCl2–ClH]+, and [CCl2–FH]+ structures are more stable than their normal tetravalent structures. Several cations should also be better described as ion–complex
structures between methyl cations and halogen atoms, e.g., [CF3–Br]+. Transition states connecting normal and ion–complex structures were also located, and potential energy diagrams were constructed
for decomposition of methane cations and to predict the fragmentation pathways. The G3X energies were used to predict the
adiabatic ionization energies (IEas) and ion fragment appearance energies (AEs) from methanes. Many of the experimental AEs correspond to the energies of transition
states instead of the thermodynamic dissociation limits.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
62.
In this paper, the weighted boundedness of parametric Marcinkiewicz integral and its commutator with rough kernels are considered. In addition, the weak type norm inequalities for parametric Marcinkiewicz integral and its commutator with different weight functions and Dini kernel are also discussed. 相似文献
63.
在物理实验中引入“计算机应用”是当前教改的任务之一。也是实验教学发展的必然趋势。本通过重力加速度和型材杨氏模量的测量实验,说明计算机通信接口在物理实验中应用的可行性。 相似文献
64.
Exploring the idea of Broadhurst on the “sixth root of unity” we present an ansatz for construction of a basis of transcendental numbers for the -expansion of single mass scale diagrams with two particle massive cut. As example, several new two- and three-loop master integrals are calculated. 相似文献
65.
Doria Affane 《Applicable analysis》2013,92(12):1677-1690
This article studies some Bolza-type problems governed by second-order differential inclusions with two boundary conditions, where the controls are Young measures. 相似文献
66.
Gisle Øye Johan Sjöblom Michael Stöcker 《Journal of Dispersion Science and Technology》2013,34(1):49-63
Ti-MCM-48 mesoporous materials have been synthesized by sequential addition of alkoxides. The atomic ratio of Si and Ti in the synthesis gel was 40 and 5, respectively. The materials were characterized by means of powder XRD, N2 adsorption-desorption measurements. HREM, 29Si MAS NMR, diffuse reflectance FT-IR spectroscopy, electrophoretic mobility measurements and electron probe microanalysis. 相似文献
67.
We study systematically an extended Bose-Hubbard model on the triangular lattice by means of a meanfield method based on the Gutzwiller ansatz. Pair hopping terms are explicitly included and a three-body constraint is applied. The zero-temperature phase diagram and a variety of quantum phase transitions are investigated in great detail. In particular, we show the existence and the stability of the pair supersolid phase. 相似文献
68.
Natália D.D. CararetoMariana C. Costa Marlus P. RolembergM.A. Krähenbühl Antonio J.A. Meirelles 《Fluid Phase Equilibria》2011,303(2):191
This study is part of a work developed in the author's research group on the solid-liquid equilibrium of fatty substances. The phase diagrams of the following fatty alcohol systems were determined by differential scanning calorimetry (DSC): 1-octanol + 1-dodecanol, 1-octanol + 1-tetradecanol, 1-decanol + 1-tetradecanol, 1-decanol + 1-hexadecanol and 1-dodecanol + 1-octadecanol. The liquidus lines of three of these systems were previously reported in the literature but the other two systems were never published. Moreover other transitions, in addition to the eutectic temperature, were also detected in all the systems. A region of solid solution at the extreme left of the phase diagrams was observed for all the binary mixtures. Polarized light microscopy was used to complement the characterization of the systems for a full grasp of the phase diagrams. The solid-liquid equilibrium was modeled using the Margules 2-suffix, Margules 3-suffix, NRTL and UNIFAC Dortmund equations. 相似文献
69.
Ernesto San-Blas Mayamarú Guerra Edgar Portillo Iván Esteves Nestor Cubillán Ysaías Alvarado 《Vibrational Spectroscopy》2011,57(2):220-228
The use of Fourier transform mid-infrared spectroscopy with attenuated total reflection for characterizing entomopathogenic nematodes is evaluated for the first time. The resulting spectra of Steinernema glaseri and Heterorhabditis indica were compared with the spectrum of Caenorhabditis elegans. In the absorption spectra generated by the nematodes samples, the absorption bands were assigned to the molecular species and some important components were identified including triglycerides, trehalose, glycogen and collagen. Also, the use of star diagrams for the fingerprint section of nematode spectra for separating genera is discussed. 相似文献
70.
Joel Brewster Lewis 《Journal of Combinatorial Theory, Series A》2011,118(4):1436-1450
We define a class Ln,k of permutations that generalizes alternating (up-down) permutations and give bijective proofs of certain pattern-avoidance results for this class. As a special case of our results, we give bijections between the set A2n(1234) of alternating permutations of length 2n with no four-term increasing subsequence and standard Young tableaux of shape 〈n3〉, and between the set A2n+1(1234) and standard Young tableaux of shape 〈3n−1,2,1〉. This represents the first enumeration of alternating permutations avoiding a pattern of length four. We also extend previous work on doubly-alternating permutations (alternating permutations whose inverses are alternating) to our more general context.The set Ln,k may be viewed as the set of reading words of the standard Young tableaux of a certain skew shape. In the last section of the paper, we expand our study to consider pattern avoidance in the reading words of standard Young tableaux of any skew shape. We show bijectively that the number of standard Young tableaux of shape λ/μ whose reading words avoid 213 is a natural μ-analogue of the Catalan numbers (and in particular does not depend on λ, up to a simple technical condition), and that there are similar results for the patterns 132, 231 and 312. 相似文献