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71.
Nishikimi A Uruno T Duan X Cao Q Okamura Y Saitoh T Saito N Sakaoka S Du Y Suenaga A Kukimoto-Niino M Miyano K Gotoh K Okabe T Sanematsu F Tanaka Y Sumimoto H Honma T Yokoyama S Nagano T Kohda D Kanai M Fukui Y 《Chemistry & biology》2012,19(4):488-497
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72.
A. Saitoh 《Journal of Raman spectroscopy : JRS》2007,38(5):537-542
Raman scattering from BiI3 and SbI3 crystals has been studied at hydrostatic pressures up to 2 GPa. The wavenumbers monotonically increased with pressure for all modes in BiI3. Although both crystals belong to the same space group, the pressure coefficients of SbI3 were significantly different from those of BiI3. At pressure P0 = 0.92 ± 0.01 GPa, the pressure coefficients of all modes changed. Above P0, all modes in SbI3 had positive pressure coefficients as they have in BiI3. By comparing this unusual behavior of the Raman lines in SbI3 around P0 with the results in BiI3 and comparing the two lattice structures, we suggest that the type of bonding of SbI3 changes to become more ionic and hence more similar to the bonding of BiI3. This change in structure is supported by changes in the bandwidth of the self‐trapped exciton (STE) luminescence and the slope of the absorption edge photon energy versus pressure. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
73.
74.
Ca2+-doping effects were studied on the N-type ferrimagnet of NdVO3. The chemical pressures by Ca2+-doping induced lowering of ferrimagnetic transition temperature Tc and compensation temperature θc, resulting in the phase transition from N- to P-type ferrimagnetic phase. In the N-phase, spontaneous magnetization Msp becomes zero at finite temperature θc and in the P-phase, Msp is positive in whole temperature range. It was revealed that NdVO3 and Ca0.1Nd0.9VO3 located in the N-phase and Ca0.2Nd0.8VO3 in the P-phase. This N→P transition by the chemical pressure was discussed by the intra- and inter-sublattice exchange integrals estimated from the molecular field approximation. 相似文献
75.
S. Hagimura T. Saitoh Y. Yagihara 《Annals of the Institute of Statistical Mathematics》1988,40(3):419-438
Cement plant process is full of internal noise sources and feedback loops. Therefore, statistical approach is required to understand its dynamic characteristics. Time series analysis has been applied to some important subprocesses of a cement plant process. These are the vertical mill process, calcining process and clinker cooling process. Based on the AR models of these, a set of optimum controllers have been designed by modern control theory. Successful results of application are reported in this paper. A method of determining optimal production level is also discussed. 相似文献
76.
Nickel(II), copper(II) and zinc(II) ions are extracted from an aqueous solution into carbon tetrachloride as their diethyldithiocarbamate (DDC) chelates. The extract, after removal of the solvent, is treated with meso-tetraphenylporphine (TPP) in benzyl alcohol at 140°C for 60 min. Quantitative conversion of the DDC chelate to the TPP chelate is obtained over the range 0.25–4.5 μg of each metal by use of 3 μgmol of TPP. The reaction mixture is analysed by reversed-phase high-performance liquid chromatography with spectrophotometric detection at 412 nm. Simultaneous determination of Cu and Zn in NBS bovine liver is possible by this procedure. 相似文献
77.
Transmission loss of holey fiber is found to depend on its structure, and to be caused by Rayleigh scattering at glass surface. Under this loss dependence, most promising is optical wiring application, for which fiber designs to realize bend-insensitivity and single-modedness are presented. 相似文献
78.
79.
Nobuo Kitada Tsuyoshi Saitoh Yuma Ikeda Satoshi Iwano Rika Obata Haruki Niwa Takashi Hirano Atsushi Miyawaki Koji Suzuki Shigeru Nishiyama Shojiro A. Maki 《Tetrahedron letters》2018,59(12):1087-1090
The synthesis and bioluminescence of allyl-substituted luciferin derivatives as substrates for firefly luciferase are reported. The allylation of luciferins induced bathochromic shift (15–40?nm) of the bioluminescence emission. Upon combination with other chemical modifications for bioluminescence wavelength tuning, novel red emitting luciferin analogues were obtained with emission maxima at 685 and 690?nm. 相似文献
80.
An improved, simple and sensitive analytical method for low molecular weight organic acids has been developed. A mixture of acetic, propionic, butyric, glycolic, lactic, 2-hydroxybutyric, malonic, succinic, glutaric, tartaric and citric acids was separated on a semi-rigid styrene-divinylbenzene copolymer-based H-type cation-exchange resin (ULTRON PS-80H) based on an ion exclusion chromatographic (IEC) mechanism, with detection using electrospray ionization mass spectrometry (ESI-MS). Formic or acetic acid was used as a mobile phase to separate the carboxylic acids within 15 min. For liquid chromatography/mass spectrometry (LC/MS), the ESI interface was used in both positive and negative ionization mode. ESI produced reasonable signals from positive ions, [M+NH(4)](+), of acetic, propionic and butyric acids and from negative ions, [M-H](-), of glycolic, lactic, 2-hydroxybutyric, malonic, succinic, glutaric, tartaric and citric acids. The effects of ionization parameters, source temperature, capillary voltage and cone voltage, on sensitivity and linearity were examined. Linear plots of peak area versus concentration were obtained over the range 0.1-20 ppm for MS detection. The detection limits of the target carboxylic acids calculated at signal-to-noise (S/N) ratio of 3 ranged from 9 to 59 ppb. The reproducibility of retention times and peak areas were 0.55-1.25 and 0.85-2.45%, respectively. 相似文献