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951.
Y Sakakibara I Saito T Oda H Tsujibo Y Inamori Y Sato 《Chemical & pharmaceutical bulletin》1992,40(8):2115-2119
We examined the inhibitory activities of 3,3'-dihydroxy-alpha,beta-diethylstilbene (DDS) and 3,3',4,5'-tetrahydroxystilbene (THS) on microtubule assembly in vitro and their effects on chromosome number and cellular microtubule networks in Chinese hamster V79 cells. DDS showed half the inhibitory activity of diethylstilbestrol (DES) on microtubule assembly in vitro, while THS had none of the inhibitory activity. DDS induced tetraploid at 30 microM, whereas THS was found to be inactive. Furthermore, DDS disturbed cellular microtubule networks at 100 microM. We also examined the effects of DES, DDS and THS on cellular actin networks in mouse BALB 3T3 cells. DES induced a change of actin stress fiber distribution and THS had similar activity, while DDS showed no activity. 相似文献
952.
T. Sato T. Yamaguchi W. Izumida S. Tarucha H. Z. Song T. Miyazawa Y. Nakata T. Ohshima N. Yokoyama 《Physica E: Low-dimensional Systems and Nanostructures》2004,21(2-4):506
By using the semiconductor nano-pillar with a graded-dope configuration, we implemented the measurement for a single-electron transport through an individual InAs self-assembled quantum dot (SAQD). An atomic-force microscope observation showed that the SAQD had a disk-like shape with a diameter of 30 nm. We succeeded in observing a significant diamagnetic shift of the Coulomb oscillation peak under the magnetic field applied perpendicular to the disk plane. The measurement gave us a lateral confinement energy of 14 meV and an electron effective mass of 0.039, which provided us with quantitative evidence that the constituent material of the observed quantum dot originates from the InAs SAQD. 相似文献
953.
Calcia-doped ceria is of potential interest as an ultraviolet (UV) radiation blocking material in personal care products because of the excellent UV light absorption property and low catalytic ability for the oxidation of organic materials superior to undoped ceria. In order to reduce the oxidation catalytic activity further, calcia-doped ceria was coated with amorphous silica by means of seeded polymerization technique. Generally, nanoparticles of inorganic materials do not provide a good coverage for human skin because of the agglomeration of the particles. The platy particles are required to enhance the covering ability of inorganic materials. This can be accomplished by synthesis of calcia-doped ceria/mica nanocomposite with subsequent silica coating to control catalytic activity of calcia-doped ceria. Calcia-doped ceria/mica nanocomposite was prepared by soft solution chemical method followed by silica coating via seeded polymerization technique. Silica coated calcia-doped ceria/mica nanocomposite was characterized by X-ray diffraction, SEM, TEM, XPS and FT-IR. 相似文献
954.
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
955.
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
956.
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
957.
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
958.
959.
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
960.
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