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41.
The purpose of the paper is to construct a supersymmetric Lagrangian within the framework of classical mechanics which would
be regarded as a candidate for passage to supersymmetric quantum mechanics.
The authors felicitate Prof. D S Kothari on his eightieth birthday and dedicate this paper to him on this occasion. 相似文献
42.
This paper proposes a method for the creation of hybrid meshes with embedded surfaces for viscous flow simulations as an extension of the multiple marching direction approach (AIAA J. 2007; 45 (1):162–167). The multiple marching direction approach enables to place semi‐structured elements around singular points, where valid semi‐structured elements cannot be placed using conventional hybrid mesh generation methods. This feature is discussed first with a couple of examples. Elements sometimes need to be clustered inside a computational domain to obtain more accurate results. For example, solution features, such as shocks, vortex cores and wake regions, can be extracted during the process of adaptive mesh generation. These features can be represented as surface meshes embedded in a computational domain. Semi‐structured elements can be placed around the embedded surface meshes using the multiple marching direction approach with a pretreatment method. Tetrahedral elements can be placed easily instead. A couple of results are presented to demonstrate the capability of the mesh generation method. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
43.
S. K. Soni Sudhir Malik R. K. Shivpuri 《Zeitschrift für Physik A Hadrons and Nuclei》1994,348(4):311-315
Experimental results on some characteristics of high multiplicity (≧45) proton-AgBr interactions at 800 GeV are presented. The results are compared with those in lower multiplicity regions as well as for CNO target. The various parameters investigated here are pseudorapidity distribution, mean normalised multiplicity, mean number of intranuclear collisions and normalised pseudorapidity. 相似文献
44.
We consider the effective action of the chiral quark model to leading order in the number of colors. A set of massive ghost-like Gervais-Lee fermion doublets is introduced which effectively simulate an asymptotically free behavior for the quarks at short distances. This suppresses the vacuum instability and leaves the Wess-Zumino sector unspoiled. At small momenta, we show that the action generated in this way compares well with experiment by performing a chiral expansion up to fourth order. It is found that this action supports stable soliton solutions with baryon number one. Masses, mass-splittings and the sigma-term are estimated in theSU(2) limit.Unité de Recherche des Universités Paris 11 et Paris 6 associée au CNRS 相似文献
45.
The pressure dependence of various phonon modes has been investigated through the ferro-paraelectric phase transition. Most
mode frequencies harden before levelling off above the phase transition. Mode Grüneisen parameters are estimated from the
pressure dependence of phonon frequencies. 相似文献
46.
Soni R Cheung FK Clarkson GC Martins JE Graham MA Wills M 《Organic & biomolecular chemistry》2011,9(9):3290-3294
Ru(II) complexes of TsDPEN containing two alkyl groups on the non-tosylated nitrogen atom are poor catalysts for asymmetric transfer hydrogenation of ketones and imines; this observation provides direct evidence for the importance of the N-H interaction in the transition state for ketone reduction. 相似文献
47.
48.
Chiral discrimination and recognition is important in peptide biosynthesis, amino acid synthesis and drug designing. Detailed
structural information is available about the peptide synthesis in ribosome. However, no detailed study is available about
the discrimination in peptide synthesis. We study the conformational energy variation of neutral methoxy phenyl alanine molecule
as a function of its different dihedral angle to locate the minimum energy conformation using quantum chemical theory. We
compared the intermolecular energy surfaces of phenyl alanine molecule in its neutral and zwitterionic state using quantum
chemical theory as a function of distance and mutual orientation. The energy surfaces are studied with rigid geometry by varying
the distance and orientation. The potential energy surfaces of L-L and D-L pairs are found to be dissimilar and reflect the underlying chirality of the homochiral pair and racemic nature of the heterochiral
pair. The intermolecular energy surface of homochiral pair is more favourable than the corresponding energy surface of heterochiral
pair. 相似文献
49.
We employ the hybrid soliton model of the nucleon consisting of a topological meson field and deeply bound quarks to investigate the behavior of the quarks on soliton matter as a function of density. We investigate a particular possible ground state by placing the solitons on a spatial lattice. The model suggests the transition of matter from a color insulator to a color conductor above a critical density of a few times normal nuclear density. 相似文献
50.
The oxide system Bi2.2Ca2.8−x
Sr
x
Cu2O
y
has been investigated for superconductivity as a function of Ca/Sr ratio withx=0.7, 1.0, 1.4 and 1.8. All these compositions are found to be superconducting with onset temperature in the range of 80–90
K implying a large homogeneity range between Sr and Ca for the superconductivity to occur in this system. Effect of partial
replacement of Bi by rare earths has been studied and it is observed that 20% replacement of Bi by Nd and Eu does not significantly
affect the superconducting transition temperature. 相似文献