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651.
652.
653.
The d-band effects on the reconstruction of the (001) surface of Cr, Mo and W are discussed with a tight-binding model. Response functions corresponding to some models for the reconstruction and their q-dependence are calculated by using Haydrock et al.'s recursion method. The present calculation shows that an energy gain by broadening the surface state peak near the Fermi energy is most remarkable for the model proposed by Debe and King, and therefore gives a theoretical support to it. The energy gain is attributed to an enhancement in the bonding property by pairing of surface atoms in the Debe and King model. Response functions without an electron-phonon matrix element (EPME) are also calculated, which show only a very weak q-dependence. Detailed discussions are given on the mode dependence, that is, on the effect of EPME. 相似文献
654.
Serum levels of thyroxine (T4)-binding globulin (TBG) were determined by a radioimmunoassay using cellulose-linked antibody to TBG. Values obtained in healthy young adults averaged 1.62 +/- 0.25 (SD) mg/100 ml, and no significant difference wwas detected between males and females. The TBG levels remained within the normal limit in hyperthyroidism while they were significantly increased in hypothyroidism. Interestingly enough, TBG levels were significantly elevated in chronic thyroidities with no overt hypothyroidism. In normal pregnancy, TBG was increased slightly in the first trimester, and markedly in the second and third trimesters. In one case of congenital TBG deficiency, no immunoreactive TBG was detected. It was demonstrated, further, that an inverse relationship (r = -0.7593) existed between the TBG level and serum triiodothyronine uptake index, and that a direct relation (r = +0.6557) was present between the TBG level and T4 in sera from normal subjects and pregnancy. Ratios of T4/TBG were markedly increased in hyperthyroidism, and decreased in hypothyroidism, showing no overlap with the normal subjects, whereas they were below the normal limit in half the cases in the second and third trimesters of pregnancy. The radioimmunoassay for TBG was useful in evaluating hypothyroid states, because it could differentiate the increase in T4 associated with elevated TBG from hyperthyroidism. 相似文献
655.
The NADH model reduction of inactivated carbonyl compounds was achieved by he combination of an acid-stable NADH analogue and strong proton sources (HCl or benzenesulfonic acid). 相似文献
656.
Seiji Shinakai Hisatake Hamada Yumiko Kusano Osamu Manabe 《Tetrahedron letters》1979,20(37):3511-3514
By the use of an acid-stable NADH analogue (3-carbamoyl-N-benzyl-1,4-dihydroquinoline) NADH model reduction of benzoylformic acid in aqueous solution was achieved, for the first time, at pH region where the carboxyl group is undissociated. 相似文献
657.
Yoshiaki Hamada Masamichi Tsuboi Takahiro Matsuzawa Kaoru Yamanouchi Kozo Kuchitsu Yoshihiro Koga Shigeo Kondo 《Journal of Molecular Spectroscopy》1984,105(2):453-464
Infrared absorption spectrum of allylimine in the gas phase was measured for the first time. The spectrum consisted of two rotational isomers, cis and trans, around the CC bond. The relative population of the trans form was 70–80%, and the rest was for the cis form at room temperature. This intermediate molecule was produced by the thermal decomposition of diallylamine and by the isomerization of propargylamine. The vibrational assignments were made with the help of an ab initio MO calculation. The half-life in the absorption cell was about 20 min. 相似文献
658.
TCNE photo-sensitized decompositions of oxasilacyclopropane (1) generated carbene and silanone, while the DCA sensitized or direct photolysis of (1) gave silylene and indanone. 相似文献
659.
660.
Yoshikazu Mizuguchi Kentaro Hamada Kazuki Goto Hiroshi Takatsu Hiroaki Kadowaki Osuke Miura 《Solid State Communications》2012,152(12):1047-1051
The low-temperature crystal structure of Fe1.13Te, which exhibits an anomalous two-step magnetic transition, was clarified by the systematic x-ray diffraction measurements. It was found that two-step structural phase transition, tetragonal–orthorhombic–monoclinic, occurred correspondingly to the two-step magnetic transition. The detailed analysis of the profile at 5 K indicated the coexistence of the minor orthorhombic area inside the major, monoclinic lattice, which could explain the lower-shift (suppression) of the antiferromagnetic transition temperature in Fe1.13Te and suggest a possibility of superconductivity at the domain boundary. 相似文献