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51.
We present a gluon jet model for the heavy quarkonium decay incorporating the color neutralization mechanism. Postulating that final hadrons are produced from the color singlet quark-antiquark pair originated each from different gluons, we formulate the production mechanism of hadrons from gluons explicitly. The fragmentation function thus obtained can describe the hadron production not only in the fragmentation region but also in the central one owing to the usage of the Sudakov variables. The result of the average charged multiplicity from Υ(9.46) is in reasonable agreement with the data, in contrast to the naive estimates. Furthermore, the inclusive momentum and multiplicity distributions are discussed.  相似文献   
52.
Under the assumption that a scalar diquark coexists in part of the time with a single quark within a nucleon, which is favored to describe the higher twist effects of both γ and ν induced nucleon structure functions consistently, we consider how its presence affects nucleon properties. It is shown that the sum rule and the magnetic moment constrain its contribution strongly and the asymmetry is quite sensitive to it. In particular, theR L T ratio can be explained in terms of the large transverse momentum of the diquark which arises from the consideration on the neutron charge radius value.  相似文献   
53.
54.
A series of solvable lattice models with face interaction are introduced on the basis of the affine Lie algebraX n (1) =A n (1) ,B n (1) ,C n (1) ,D n (1) . The local states taken on by the fluctuation variables are the dominant integral weights ofX n (1) of a fixed level. Adjacent local states are subject to a condition related to the vector representation ofX n . The Boltzmann weights are parametrized by elliptic theta functions and solve the star-triangle relation.  相似文献   
55.
We develop the theory of multi-polariton scattering via excitonic molecules under strong excitation. New emission lines, denoted by X- and L-bands, were observed at slightly lower energy side of two-photon Raman line in CuCl under strong excitation. In terms of the present theory, these lines can be for the first time assigned to the multi-polariton scatterings associated with the coherently (virtually) and incoherently (realy) created excitonic molecules, respectively.  相似文献   
56.
We have observed high resolution 13C NMR spectra in k-intercalated stages 2, 3, 4 and 6 HOPG compounds. The sample was a block itself or sliced one of HOPG. From T1T of each resolved line we obtained a distribution of density of states N(EF) at the Fermi level among the graphite layers.  相似文献   
57.
58.
The heat capacities of copper(II) formate tetrahydrate and tetradeuterate have been measured from 12 to 300 K with an adiabatic calorimeter. They have sigmoidal temperature dependence except near the antiferroelectric-paraelectric transition temperatures, 235.78 ± 0.05 K and 245.64 ± 0.05 K, respectively. The corresponding enthalpy changes are 836.0 ± 1.0 J mol?1 and 936.9 ± 0.5 J mor?1. The entropy changes are 3.546 ± 0.005 JK?1mol?1 and 3.814 ± 0.002 JK?1 mol?1. The heat capacities are larger in the high temperature phase than in the low temperature phase, the difference amounting to 5.74 JK?1 mol?1 and 7.15 JK?1 mol?1 for the hydrate and the deuterate, respectively. The heat capacity anomaly is compared with those in tin(II) chloride dihydrate and potassium hexacyanoferrate trihydrate and discussed in relation to the structure of the hydrogen bond networks in these substances. The discussion is extended to include possible properties of the hydrogen bond frameworks in ices Ih and II.  相似文献   
59.
Asymmetric reduction of α-ketoester with a chiral dihydronicotinamide was significantly affected by chiral aromatic additives, capable of exerting an attractive interaction with dihydropyridine ring, which was further consolidated through with magnesium.  相似文献   
60.
The formation of 1-substituted-3-hydroxy-1H-indazole and 1-substituted-benzimidazolin-2-one derivatives by thermal reaction of N-substituted-N-arylcarbamoyl azides was examined.  相似文献   
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