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991.
The magnetic and transport properties of a new cubic KSbO3-type ruthenate, (Ba1−xSrx)2Ru3O9 (x≈0.35), have been investigated. The crystal structure has a singular geometry in which ruthenium atoms form an ideal three-dimensional orthogonal dimer lattice. The magnetic susceptibility is Pauli-paramagnetic but exhibits an anomalous temperature dependence reminiscent of a gap-like behavior. The resistivity exhibits a metallic behavior, except for a rise at low temperature. 相似文献
992.
Jun Wang Shu Yin Tsugio Sato Fumio Saito 《Journal of Physics and Chemistry of Solids》2007,68(2):189-192
Doping sulphur into titania has been tried using TiS2 as a doper based on the mechanically induced solid-state reaction between TiO2 and TiS2. The prepared samples have been characterized by X-ray diffraction (XRD), Raman spectroscopy and UV-Vis reflectance spectroscopy. Raman analysis, particularly has been proved to be effective in assessing the sulphur doping by correlating the oxygen deficiency of the doped oxide with the change of active Eg mode of rutile phase. 相似文献
993.
Masafumi Yano Yutaka Ishida Kazunobu Sato Munetaka Oyama 《Journal of Physics and Chemistry of Solids》2004,65(4):733-736
A series of N,N,N′,N′-tetraaryl-1,3-phenylenediamines with various substituents at the para-position of peripheral rings were designed and synthesized. Electrochemical and novel electron transfer stopped-flow methods were invoked for characterizing the absorption spectra of the corresponding short-lived mono- and dicationic states. Both thermodynamic and kinetic stabilization are required to extend the lifetime of the dicationic states. Useful molecular design rules for stabilizing the dicationic states of N,N,N′,N′-tetraaryl-1,3-phenylenediamines as precursors for positively charged high-spin systems were elucidated. 相似文献
994.
A. Bensalah M. Nikl E. Mihokova N. Solovieva A. Vedda H. Sato T. Fukuda G. Boulon 《Radiation measurements》2004,38(4-6):545-548
Single crystals of Yb2+-doped LiCaAlF6 were grown by the Czochralski technique under CF4 atmosphere. Photoluminescence, thermally stimulated luminescence and decay kinetics of Yb2+ centre in the LiCaAlF6 host were measured in the 4–300 K temperature interval. Phenomenological two excited-state-level model is introduced to obtain quantitative characteristics of the excited state dynamics of Yb2+. The role of Yb2+ centre in trapping processes is discussed. Moreover, defect centres related to LiCaAlF6 host were found. 相似文献
995.
996.
We give a determinant expression for the Bartholdi zeta function of a digraph which is not symmetric. This is a generalization of Bartholdi’s result on the Bartholdi zeta function of a graph or a symmetric digraph. 相似文献
997.
Kazuhisa Sato Tetsuya Sakairi Toshikuni Yonemoto Teiriki Tadaki 《Journal of membrane science》1995,100(3):209-216
A new electrodialysis with charge-mosaic membranes was proposed to achieve efficient desalination of a mixed solution of an amino acid and an inorganic salt. For such a mixed solution, the conventional electrodialytic desalination with both cation-and anion-exchange membranes had resulted in a considerable loss of the amino acid through the membranes. In this method, however, the amino acid in the desalination channel of the electrodialyzer migrates away from the membranes so that the permeation loss of the amino acid through the membrane can be prevented.
Batchwise desalination experiments by this method were carried out with a glutamic acid or arginine solution including NaCl under the condition of constant electric current density. Similar experiments by the conventional method were also carried out. As a result of comparing both methods, the amino acid loss in this method became much smaller than that in the conventional one. It was confirmed that this method was very useful for the desalination of an amino acid solution. The effects of operating conditions on the desalination process are also discussed. 相似文献
998.
999.
Stereoselective reduction of α-substituted β-keto esters is achieved by the combined use of hydrostannane/organotin triflate. syn-Aldols are obtained with more than 90% selectivities. 相似文献
1000.