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101.
Yoji Imai Yasuhiko Takahashi Toshiya Kumagai 《Journal of magnetism and magnetic materials》2010,322(18):2665-43
Geometrical optimization of tetra-3d metal nitrides (Mn4N, Fe4N, Co4N, and Ni4N) has been performed and the relations of their energies (E) and their total magnetic moments (M) are obtained by plane-wave-basis density-functional calculations without any assumption of specific spin arrangement. The E vs. M relations obtained for Fe4N and Mn4N have a bimodal character. The ground state of Fe4N is a high-spin state, which would correspond to the ferromagnetic character, while that of Mn4N is a low-spin state, which would correspond to the observed ferrimagnetic character. Lattice constants and total magnetic moments of these tetra-3d metal nitrides are almost accurately predicted. From the spin-polarized densities of states curves, Co4N would have the largest spin polarization ratio of 0.88, which suggests Co4N can be a candidate material for ferromagnetic electrodes for spin-injection. 相似文献
102.
We investigated simultaneous determination of haloperidol (HAL), its three metabolites [reduced HAL (R-HAL), 3-(4-fluorobenzoyl)propionic acid (FBPA) and 4-(4-chlorophenyl)-4-hydroxypiperidine (CPHP)] and two related compounds [spiperone (SPI) and droperidol (DRO)] in phosphate-buffered saline using high-performance liquid chromatography (HPLC) coupled with dual ultraviolet detection (220 and 250 nm). Retention times of HAL, R-HAL, FBPA, CPHP, SPI and DRO were 16.8, 11.8, 10.2, 4.1, 12.6 and 8.3 min, respectively. Their lower limits of detection were 7.5, 14, 4.5, 12, 10 and 20 ng/mL in the same order. The coefficients of variation for their intra- and inter-day assays were less than 7.8 and 9.4%, respectively. Of the other centrally acting drugs, only amoxapine interfered with the peak of DRO. Using our procedure, the binding study of tested compounds to synthetic melanin, human serum albumin and alpha1-acid glycoprotein was performed by determining the unbound concentration to total concentration ratio. These results indicated that simultaneous assay of HAL, R-HAL, FBPA, CPHP, SPI and DRO in phosphate-buffered saline by HPLC equipped with dual ultraviolet detection is simple, sensitive and reproducible. Also, our assay system can be applied to the binding study of these compounds to synthetic melanin, human serum albumin and alpha1-acid glycoprotein. 相似文献
103.
104.
Yasuhiko Sato 《Journal of Functional Analysis》2010,259(2):453-476
For projectionless C∗-algebras absorbing the Jiang-Su algebra tensorially, we study a kind of the Rohlin property for automorphisms. We show that the crossed products obtained by automorphisms with this Rohlin property also absorb the Jiang-Su algebra tensorially under a mild technical condition on the C∗-algebras. In particular, for the Jiang-Su algebra we show the uniqueness up to outer conjugacy of the automorphism with this Rohlin property. 相似文献
105.
Yasuhiko Arai Ryouichi Shimamura Shunsuke Yokozeki 《Optics and Lasers in Engineering》2009,47(5):563-569
The novel measurement method based on the virtual speckle patterns has been reported. This method has the feature of analyzing the deformation map of an object in high resolution without any information except for speckle pattern images under a deformation process. In this paper, the method is applied to the measurement of dynamic events including a complex deformation distribution. The optical system of the method is improved in order to deal with the complex deformation distribution, which includes the increase and the decrease distributions. In experiments, the phenomenon of collision of the metal sphere on the thin polymer film is analyzed. The method can analyze the large deformation measurement of dynamic events, which cannot be measured by ordinary methods. It is confirmed that the measurement accuracy of this method even in measurements of dynamic events is high. 相似文献
106.
Toru Takahashi Yasuhiko Hori Ichiro Sato 《Journal of polymer science. Part A, Polymer chemistry》1968,6(8):2091-2102
The ceric salt-initiated polymerization on acrylamide and graft copolymerization of acrylamide onto cellulose were studied. The mechanism of the ceric salt-initiated polymerization of acrylamide in the homopolymerization system can be explained by a radical mechanism based upon Ce4+-coordinated acrylamide, and the mechanism of the ceric salt-initiated graft copolymerization of acrylamide onto cellulose can be explained in two ways: a free-radical mechanism with the ceric—cerous redox system, and a radical mechanism based upon Ce4+-coordinated acrylamide. The velocities of initiation, propagation, and termination in the redox mechanism are quite different from those in the coordinated radical mechanism. From the infrared absorption and nuclear magnetic resonance spectra measurements it is concluded that the structure of the ceric-coordinated acrylamide is the π-complex. 相似文献
107.
Yasuo Oshiro Yasuhiko Shirota Hiroshi Mikawa 《Journal of polymer science. Part A, Polymer chemistry》1974,12(10):2199-2206
N-Vinylindole (NVI) was copolymerized with such electron-accepting monomers as fumaronitrile (FN) or diethyl fumarate (DEF) under initiation with a radical catalyst. The compositions of the copolymers varied from 1:1.1 to 1:1.85 (NVI:FN or DEF). The FN or DEF content in the copolymer increased with increase in the molar fraction of the FN or DEF monomer in the monomer feed. It was suggested that both copolymers have a 1:1 recurring unit of NVI and the electron-accepting monomer, thus being alternating copolymers, and that further addition of the electron-accepting monomer to the indole ring occurred at its electron-rich β-carbon atom. 相似文献
108.
Nagashima H Gondo M Masuda S Kondo H Yamaguchi Y Matsubara K 《Chemical communications (Cambridge, England)》2003,(3):442-443
A novel organoruthenium(III) amidinate, (eta5-C5Me5)RuCl(eta-iPrN=C(Me)NiPr) (2), has been prepared by oxidation of organoruthenium amidinate, (eta5-C5Me5)Ru(eta-iPrN=C-(Me)NiPr) (1), by organic chlorides; both 1 and 2 are found to be good catalysts for atom-transfer cyclization of N-allyltrichloroacetamides which are useful for successful preparation of a pyrrolizidine alkaloid skeleton under mild conditions. 相似文献
109.
A sensitive, simple and reliable method using high-performance liquid chromatographic (HPLC) assay of fluvoxamine (FLU), a selective serotonin reuptake inhibitor (SSRI), in rat plasma after pre-column derivatization with 4-fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) was developed in this study. Extracted plasma samples were mixed with NBD-F at 60 degrees C for 5 min and injected into HPLC. Retention times of FLU and an internal standard (propafenone) derivative were 15.5 and 13.5 min, respectively. The calibration curve was linear over the range 0.015-1.5 microg/mL (r2 = 0.9985) and the lower limits of detection and quantification of FLU were 0.008 and 0.015 microg/mL, respectively, in 100 microL of plasma. The derivative sample was stable at 4 degrees C for 1 day. The coefficients of variation for intra-day and inter-day assay of FLU were less than 8.3 and 9.6%, respectively. Other SSRIs and centrally acting drugs did not interfere with the peak of the FLU derivative. The method was applied for analysis of the plasma samples from rats treated with FLU. These results indicate that the method presented is useful to determine the FLU levels in rat plasma of volumes as small as 100 microL and can be applied to pharmacokinetic studies. 相似文献
110.
An efficient vector processing algorithm generating PK supermatrices has been developed, in particular aiming at calculations on large molecules. The algorithm utilizes the recurrence relations for electron repulsion integrals. The PK supermatrices are listed in a nearly canonical order so that the Fock matrix generation is efficiently vectorized, no temporary ERI and PK files being used. This is effected by partition of the basis set (atomic orbitals) into subsets of certain appropriate sizes, and the partition approach is named as the three-dimensional partial space method. A high-speed Hartree–Fock calculation including integrals and SCF procedures is achieved. © 1992 by John Wiley & Sons, Inc. 相似文献