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111.
The combustion calorimetry on the NbS system has been carried out under an oxygen atmosphere at 453°C using a Calvet-type twin calorimeter. The partial molar enthalphies of the formation of solid solution for both 2S-NbSx and 3S-NbSx phase on the NbS system has been determined. 相似文献
112.
The resonance condition for triple-barrier structures with arbitrary potential is studied systematically. The quasisymmetrical triple-barrier (QST) resonance mode and the quasi-asymmetrical double-barrier (QAD) resonance mode may both exist in asymmetric triple-barrier structures. The QST consists of two submodes: a normal mode (doublet) and a degenerate mode (singlet). The critical condition for distinguishing the two modes is examined. It is confirmed that there are both unity resonant transmission and below-unit resonant transmission in the asymmetrical triple-barrier structure. Furthermore, the wavefunctions of an electron at resonance level are calculated and the confining phenomenon is studied. 相似文献
113.
114.
Akine S Taniguchi T Saiki T Nabeshima T 《Journal of the American Chemical Society》2005,127(2):540-541
Ca2+-selective recognition was achieved by using the site-selective transmetalation of homotrinuclear metallohost [L1Zn3]2+ containing a linear tetraoxime ligand. The selectivity (log(KCa/KMg) > 5.1) is comparable to those of the excellent Ca2+ receptors or sensors such as BAPTA, Quin2, and K23E1. X-ray crystallography revealed that the Ca2+ complex [L1Zn2Ca]2+ has a helical structure. On the other hand, the larger analogue H6L2 gave a mixture of [L2Zn4]2+ isomers, which selectively recognizes Ba2+ to give a single tetranuclear complex, [L2Zn3Ba]2+. 相似文献
115.
116.
Y. Onoda Y. Fujiki M. Takigawa H. Yasuoka S. Yoshikado T. Ohachi I. Taniguchi 《Solid State Ionics》1985,17(2):127-131
Frequency dependence of spin-lattice relaxation time T1 of 27Al in one-dimensional K+ ion conductor, K-Al-priderite, was measured at 45 K in the frequency range from 10.1 MHz to 55 MHz. It is found that T1 is proportional to ω1.49±0.05 and agrres well with the dependence derived by the continuum diffusion model. The intrinsic activation energy is determined to be 0.058 eV by doubling the slope ENMR=0.029 eV of the d(ln T1)/dT curve in the low temperature region. The frequency dependence of T1 in the high temperature region measured in the frequency range from 11.5 MHz to 20.8 MHz shows a tendency that the frequency dependence becomes smaller than the dependence as temperature is raised above 450 K. 相似文献
117.
Higashi T Takayama N Nishio T Taniguchi E Shimada K 《Analytical and bioanalytical chemistry》2006,386(3):658-665
A practical procedure for determining estrogens in biological fluids has been studied using liquid chromatography–electron
capture atmospheric pressure chemical ionization–mass spectrometry combined with derivatization. Among the commercially available
reagents (4-nitrobenzoyl chloride, 2,4-dinitrofluorobenzene, 4-nitrobenzenesulfonyl chloride and 4-nitrobenzyl bromide), 4-nitrobenzenesulfonyl
chloride was of the most practical use; it rapidly and quantitatively reacted with estrogens and increased the detection responses
by 8–23 times. The derivatization method allowed the reproducible and accurate quantification of serum and urine estrone and
estradiol of a pregnant woman, which is useful for diagnosis of the fetoplacental function, with small amounts (10 μl) of
sample and a simple pretreatment procedure.
Tatsuya
Higashiis Associate Professor of the Laboratory of Clinical Analytical Sciences (Professor Kazutake Shimada’s research group) at
the Graduate School of Natural Science and Technology of Kanazawa University. He received the Japan Society for Analytical
Chemistry Award for Young Scientists in 2003 and the Pharmaceutical Society of Japan Award for Young Scientists in 2006. His
current research interests are the development of methods for increasing sensitivity in LC-MS to detect and characterize trace
amounts of biologically active steroids, such as estrogens, androgens and neuroactive steroids. 相似文献
118.
Akine S Taniguchi T Matsumoto T Nabeshima T 《Chemical communications (Cambridge, England)》2006,(47):4961-4963
Complexation of linear hexaoxime ligand H6L with Zn2+ and Mn+ (= La3+, Ba2+) afforded a tetranuclear single metallohelicate [LZn3M]n+, whose inversion rate can be modulated by the central metal Mn+. 相似文献
119.
Luc Huy Hoang Nguyen T. M. Hien W. S. Choi Y. S. Lee K. Taniguchi T. Arima S. Yoon X. B. Chen In‐Sang Yang 《Journal of Raman spectroscopy : JRS》2010,41(9):1005-1010
We have measured polarized Raman spectra of MnWO4 single crystals at low temperatures, and studied the temperature dependence of the various phonon modes. From our Raman studies of the MnWO4, a new transition temperature, ∼180 K, was found. We have completely assigned the symmetries of the 18 observed Raman modes of the MnWO4, as expected from a group theoretical analysis. These Raman modes have been classified into three groups according to weak, intermediate and strong temperature dependence of the modes in each group. Six internal modes have been identified by their weak temperature dependence of the Raman wavenumbers. The temperature dependence of the wavenumbers of the Bg modes in Mg O bonds, modes of intermediate temperature dependence group, shows an anomalous behavior under 50 K. The phonon modes of strong temperature dependence show an anomalous change at ∼180 K in the linewidths. This is believed to be a new transition temperature which involves the changes in the inter‐WO6 octahedra structure. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献