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311.
312.
Akon Higuchi Masatomo Abe Jiro Komiyama Toshiro Iijima 《Journal of membrane science》1984,21(2):113-121
Permeabilities and diffusion coefficients of various gases, Ar, N2, O2, CO2, CH4, C2H4, C3H8 and C4H10, were measured for Water-swollen gel cellophane membranes. No dependence of permeabilities on gas pressure below 1 atm was found. It was observed that the permeability coefficients were not related linearly to the coefficients in bulk water. For the two states of water in the membrane, an analytical method is presented to estimate the diffusion coefficients and the solubilities in free water and non-freezing water. It was found that the diffusion coefficients in non-freezing water were lower than those in free water, and the solubilities in non-freezing water were higher than in free water for all gases studied except CO2 and C2H4, which gave reverse results. 相似文献
313.
A new type of 5-deazaflavin derivative with axial and planar chirality was synthesized as a flavoenzyme model. A novel optical resolution gave an enantiomeric pair of the 5-deazaflavins 1a,b. Compounds1a,b were optically stable and effectively discriminated PNPH enantiomers in a model reaction of intercoenzyme hydrogen transfer. 相似文献
314.
Tetsuji Kawabe Yasuaki Ohtani Kisei Kinoshita 《Zeitschrift fur Physik C Particles and Fields》1980,3(4):299-305
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
315.
Tetsuji Kawabe 《Zeitschrift fur Physik C Particles and Fields》1983,16(4):367-371
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=σ L /σ 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
316.
317.
A self-excitation of subharmonics and their higher harmonics of a low frequency oscillation which seems to be ascribed to the current-convective instability is observed. 相似文献
318.
319.
H. Shimizu Y. Ohbayashi K. Yamamoto K. Abe M. Midorikawa Y. Ishibashi Y. Takagi 《Journal of Physics and Chemistry of Solids》1976,37(4):411-415
The second-order Raman spectra of CsCl single crystals have been measured at room temperature for different Raman polarizations and crystal orientations. With the help of the calculated selection rules for a CsCl-type lattice, observed nineteen peaks and shoulders were assigned by the critical point analysis based on the neutron scattering data. By comparing the observed Raman intensities with the thermally weighted two-phonon density-of-states calculated by using a simple shell model, it has turned out that though the measured spectra are dominantly determined by the two-phonon density-of-states, the effect of the q-dependence of the polarizability cannot entirely be neglected. 相似文献
320.
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