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251.
Yoji Koike Sei-ichi Tanuma Hiroyoshi Suematsu Kohei Higuchi 《Journal of Physics and Chemistry of Solids》1980,41(10):1111-1118
Superconducting properties of pseudo-single crystals of C8K were investigated by low frequency a.c. magnetic susceptibility and electrical resistivity measurements. The measured values of Tc were between 128 and 198 mK for 13 samples. Measurements of the superconducting transition in a magnetic field revealed a remarkable anisotropy, such that if θ is defined as the angle between the applied magnetic field and the layer plane, type II superconductivity was observed for 0° ≦ ∣ θ ∣ ? 25° and type I superconductivity for 25° ? ∣ θ ∣≦ 90°. The angular dependences of Hc2 and Hc3 were fairly well-explained by the effective mass model. 相似文献
252.
A method was developed for determining the activity of lysozyme using two pipettes as a viscometer. The proposed viscometric assay uses carboxymethylchitin as a substrate and measures the enzyme activity at 22°C. The method requires only simple manipulations with the use of readily available laboratory equipment and the determination of enzyme activity is rapid. 相似文献
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255.
Esaki H Aoki F Umemura M Kato M Maegawa T Monguchi Y Sajiki H 《Chemistry (Weinheim an der Bergstrasse, Germany)》2007,13(14):4052-4063
A method for efficient and extensive H/D exchange of substituted benzene derivatives which is catalyzed by heterogeneous Pd/C in D(2)O as a deuterium source under hydrogen atmosphere is described. Multi-deuterium incorporation into unactivated linear or branched alkyl chains that bear a carboxyl, hydroxyl, ether, ester, or amide moiety and are connected with a benzene ring was achieved by using the Pd/C-H(2)-D(2)O system. The present method does not require expensive deuterium gas or any special equipment. 相似文献
256.
Yamaguchi K Okamoto N Tokuoka K Sugiyama S Uchiyama N Matsumura H Inaka K Urade Y Inoue T 《Journal of synchrotron radiation》2011,18(1):66-69
Old yellow enzyme (OYE) is an NADPH oxidoreductase which contains flavin mononucleotide as prosthetic group. The X-ray structures of OYE from Trypanosoma cruzi (TcOYE) which produces prostaglandin (PG) F(2α) from PGH(2) have been determined in the presence or absence of menadione. The binding motif of menadione, known as one of the inhibitors for TcOYE, should accelerate the structure-based development of novel anti-chagasic drugs that inhibit PGF(2α) production specifically. 相似文献
257.
The temperature dependence of dielectric constants and splay elastic constants for fluorinated phenyl bicyclohexane (PBC) binary liquid crystal (LC) mixtures is reported. The results show that the proportions of the constituent elements of binary mixtures strongly influence their anisotropic dielectric constants. For mixtures in which meta-para- and ortho-para-fluorine-substituted molecules are in equal proportion, the effectiveness of the anisotropic dielectric is equal to that with a single para-fluorine- substituted compound. The proportions of a mixture seldom affect the threshold voltage and splay elastic constants in an anti-parallel measurement cell. 相似文献
258.
Superoxide Dismutase Activity of the Naturally Occurring Human Serum Albumin–Copper Complex without Hydroxyl Radical Formation 下载免费PDF全文
Ryunosuke Kato Dr. Matofusa Akiyama Prof. Dr. Hiroyoshi Kawakami Prof. Dr. Teruyuki Komatsu 《化学:亚洲杂志》2014,9(1):83-86
The superoxide radical anion (O2.?) is biologically toxic and contributes to the pathogenesis of various diseases. Here we describe the superoxide dismutase (SOD) activity of human serum albumin (HSA) complexed with a single CuII ion at the N‐terminal end (HSA–Cu complex). The structure of this naturally occurring copper‐coordinated blood serum protein has been characterized by several physicochemical measurements. The O2.? dismutation ability of the HSA–Cu (1:1) complex is almost the same as that of the well‐known SOD mimics, such as MnIII‐tetrakis(N‐methylpyridinium)porphyrin. Interestingly, the HSA–Cu complex does not induce a subsequent Fenton reaction to produce the hydroxyl radical (OH.), which is one of the most harmful reactive oxygen species. 相似文献
259.
A Colle-Salvetti (CS)-type electron-nucleus correction in the nuclear orbital plus molecular orbital theory is proposed. The CS-type correction is designed to satisfy the cusp condition for the electron-nucleus interaction. Since the CS-type correction is expressed in terms of the electron and nucleus densities, its evaluation is computationally feasible. Numerical assessment confirms that the CS-type correction performs well for the small G2 set. 相似文献
260.
An asymmetric allylic substitution of simple allylic ethers with arylboronic acids in the presence of a rhodium(I)/(R)-DTBM-SEGPHOS catalyst has been developed. The reactions proceeded smoothly at room temperature to give the corresponding branch products with excellent regioselectivities and good to excellent enantioselectivities. 相似文献