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961.
Commutative elliptic difference operators associated with the affine root systems are constructed in terms of affine R-matrices. These operators describe the Ruijsenaars models with elliptic potentials and reduce to the Macdonald operators in the trigonometric limit. 相似文献
962.
963.
The tissue distribution of 14C-labeled DL-2-(4-(2-thienylcarbonyl) phenyl) propionic acid (suprofen) after po administration was studied in male, female, and pregnant rats by whole-body autoradiography. 14C localized rapidly in such highly vascularized tissues as liver, kidney, and lung as well as heart in rats of both sexes, but no significant uptake was found in the central nervous system. About half of the 14C in the liver and kidney was found to be unchanged suprofen; smaller amounts of 2-(4-(2-thienylhydroxymethyl)phenyl)propionic acid and 2-(4-carboxyphenyl)propionic acid were also detected. In pregnant rats, a low level was found in the uterus and placenta; the drug penetrated the fetuses to only a limited degree. No appreciable radioactivity was found in rat tissues 24 h after dosing. 相似文献
964.
965.
H. Sato Y. Masuda K. Sakai M. Doi K. Asahi Z. J. Zheng Y. Mori P. P. J. Delheij Y. Matsuda M. Iinuma H. M. Shimizu A. Masaike 《Hyperfine Interactions》1994,84(1):205-209
We have constructed an apparatus to polarize the3He nuclear spin, which will be used as a neutron spin analyzer in T- and P-violation neutron experiments. We report on principles and the present status of the method for the polarization of3He and the determination of its value.On leave from Tohoku University, Aoba-ku, Sendai 980, Japan. 相似文献
966.
967.
Kazuhiro Tanaka Yasuharu Osada Hidetoshi Kita Ken-ichi Okamoto 《Journal of Polymer Science.Polymer Physics》1995,33(13):1907-1915
Polyimides with large aromatic rings were prepared from 3,6-diaminocarbazole (CDA), N-ethyl-3,6-diaminocarbazole (ECDA), 2,7-diaminofluorene (DAF), 2,7-diaminofluorenon (DAFO), and dimethyl-3,7-diaminodibenzothiophene-5,5-dioxide (DDBT) with 2-bis(2,4-dicarboxyphenyl) hexafluoropropane dianhydride (6FDA) and 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA). Their physical properties, including gas permeability and permselectivity, were investigated in comparison with those of the related polyimides from 1,3-phenylenediamine (mPD). Glass transition temperatures of the polyimides with large aromatic rings were much higher than those of the mPD-based polyimides as a result of increased rigidity of the former polymer chains. With changing diamine from mPD to the large aromatic diamines, charge transfer (CT) interaction between the moieties of acid anhydride and diamine seems to be enhanced, judging from the red shift of absorption edge of the polyimide films and the red shift of CT excitation band of the 6FDA-based polyimides in solution. Fraction of free space (VF) was a little smaller for the polyimides with large aromatic rings except DDBT than for the mPD-based polyimides, probably because of enhancement in polymer chain-chain interactions as a result of the increased CT interaction. The DDBT-based polyimides had large VF than the mPD-based polyimides because of the nonplanar structure of neighboring dibenzothiophene-5,5-dioxide and imide rings. For the 6FDA-based polyimides, permeability coefficients to H2, O2, N2, CO2, and CH4 were in the order, DAFO < mPD ~ DAF < CDA < ECDA < DDBT. As for the membrane performance for H2/CH4, CO2/CH4, and O2/N2 systems, it is significant to change diamine from mPD to DDBT or CDA, but not to DAF or DAFO. The DDBT-based polyimides were excellent for H2/CH4 and CO2/CH4 separations. © 1995 John Wiley & Sons, Inc. 相似文献
968.
A Stroboscopic phase-shift interferometry has been developed to visualize surface acoustic wave (SAW) propagation on SAW devices quantitatively. The developed interferometry is a Fizeau-type one with a multi-mode semiconductor laser diode and an optical isolator. With the laser light illuminating stroboscopically, observed interference intensity gives information about average displacements of the vibrations. Fifty MHz SAW propagation on the surface of the SAW device has been measured with the interferometry. Distribution of the SAW along the propagation path has been observed, whose amplitude is 3 nm (p-p). Repetition accuracy evaluated with the root mean square method is 1/2500 of the laser wavelength. The system is useful for estimating and improving performances of micro-devices.Presented at 1996 International Workshop on Interferometry (IWI ‘96), August 27-29, Saitama, Japan. 相似文献
969.
970.
A q-difference analog of the sixth Painlevé equation is presented. It arises as the condition for preserving the connection matrix of linear q-difference equations, in close analogy with the monodromy-preserving deformation of linear differential equations. The continuous limit and special solutions in terms of q-hypergeometric functions are also discussed. 相似文献