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41.
Kamata J Okada T Kotake Y Niijima J Nakamura K Uenaka T Yamaguchi A Tsukahara K Nagasu T Koyanagi N Kitoh K Yoshimatsu K Yoshino H Sugumi H 《Chemical & pharmaceutical bulletin》2004,52(9):1071-1081
As part of a series of studies to discover new topoisomerase II inhibitors, novel pyrimidoacridones, pyrimidophenoxadines, and pyrimidocarbazoles were synthesized, and in vitro and in vivo antitumor activities and DNA-protein and/or DNA-topoisomerase II cross-linking activity as an indicator of topoisomerase II-DNA cleavable complex formation were evaluated. The pyrimidocarbazoles possessed high in vitro and in vivo potencies. Compound 26 (ER-37326), 8-acetyl-2-[2-(dimethylamino)ethyl]-1H-pyrimido[5,6,1-jk]carbazole-1,3(2H)-dione, showed in vitro growth inhibitory activity with respective IC(50) values of 0.049 microM and 0.35 microM against mouse leukemia P388 and human oral cancer KB. In vivo, this compound inhibited the tumor growth of mouse sarcoma M5076 implanted into mice with T/C values of 42% and 13% at 3.13 and 6.25 mg/kg/d respectively without significantly affecting the body weight. In addition, compound 26 (ER-37326) increased the formation of DNA-topoisomerase II cross-linking in P388 cells. 相似文献
42.
MNDO, a semiempirical SCF-MO method, was applied to study the structure of the borate glass. The clusters, B(OH)3, H3B3O6, B3O63?, (HO)2BOB (OH)2, (HO)2B3O3OB3O3 (OH)2, BO3[B(OH)2]3 and BO3[B3O3(OH)2]3 were treated and their geometries, the heats of reactions, the π electron systems and electronic structures were discussed. The geometry and the electronic structures show a good correspondence with the experimental data. The resonance stabilization effect of the π electron system is not so large as to control the geometries and reactions. 相似文献
43.
44.
Hema Malani Huifeng Zhong Hideyuki Tsuboi Nozomu Hatakeyama Hiromitsu Takaba Carlos A. Del Carpio 《Applied Surface Science》2008,254(23):7608-7611
The ethylene/1-butene copolymerization using constrained geometry catalyst CpSiH2-NH-TiCl2 (CGC) was investigated by the density functional theory and molecular dynamics. Structures and energetics of reactants, π-complexes, transition states, and products during insertion of ethylene and 1-butene monomers into the catalytic reactive site of the CGC were investigated by the density functional theory (DFT) using the software Dmol3, while dynamics of atoms during copolymerization process was investigated by classical molecular dynamics (MD) using the New-Ryudo-CR program. The calculated results were compared with the available experimental and theoretical ones. It was found that the ethylene insertion into Ti-Me active species is energetically more favorable than the butene one and the 2,1-butene insertion is more favorable than 1,2-butene one. Once the initial ethylene insertion has taken place, the further ethylene insertion occurring with a less energy barrier, in good agreement with experimental findings. 相似文献
45.
Nozomu Matsubara 《Annals of the Institute of Statistical Mathematics》1976,28(1):125-144
Summary According to the sequential decision theory, one is directed to; (i) stop when the posterior distribution, having been successively
watched, frist enters the domain in which by stopping he loses less, and then (ii) take that action which gives him the least
loss averaged w.r.t. the current posterior distribution (Blackwell-Girshick [1], p. 254).
For some reasons we don't know, however, the successive behavior of posterior distribution never draws the full attention
of statisticians and probabilists, though some of them have developed the asymptotic theory. As far as the sequential decision
theory is concerned, however, the asymptotic behavior tells us nothing, since the stopping rule is only related to finite
time.
Toe compute the posterior distribution time by time is a laborious task. But to site all possible posterior distributions
sometimes facilitates our manipulation of the sequential decision problem. This paper proposes some methods.
The Institute of Statistical Mathematics 相似文献
46.
47.
Masahiro Yoshida Kenji Ishii Ignace Jarrige Tetsu Watanuki Kazutaka Kudo Yoji Koike Ken'ichi Kumagai Nozomu Hiraoka Hirofumi Ishii Ku‐Ding Tsuei Jun'ichiro Mizuki 《Journal of synchrotron radiation》2014,21(1):131-135
A single‐crystal momentum‐resolved resonant inelastic X‐ray scattering (RIXS) experiment under high pressure using an originally designed diamond anvil cell (DAC) is reported. The diamond‐in/diamond‐out geometry was adopted with both the incident and scattered beams passing through a 1 mm‐thick diamond. This enabled us to cover wide momentum space keeping the scattering angle condition near 90°. Elastic and inelastic scattering from the diamond was drastically reduced using a pinhole placed after the DAC. Measurement of the momentum‐resolved RIXS spectra of Sr2.5Ca11.5Cu24O41 at the Cu K‐edge was thus successful. Though the inelastic intensity becomes weaker by two orders than the ambient pressure, RIXS spectra both at the center and the edge of the Brillouin zone were obtained at 3 GPa and low‐energy electronic excitations of the cuprate were found to change with pressure. 相似文献
48.
Remarkable Charge Separation and Photocatalytic Efficiency Enhancement through Interconnection of TiO2 Nanoparticles by Hydrothermal Treatment
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Prof. Yusuke Ide Nozomu Inami Hideya Hattori Kanji Saito Dr. Minoru Sohmiya Prof. Nao Tsunoji Prof. Kenji Komaguchi Prof. Tsuneji Sano Prof. Yoshio Bando Prof. Dmitri Golberg Prof. Yoshiyuki Sugahara 《Angewandte Chemie (International ed. in English)》2016,55(11):3600-3605
Although tremendous effort has been directed to synthesizing advanced TiO2, it remains difficult to obtain TiO2 exhibiting a photocatalytic efficiency higher than that of P25, a benchmark photocatalyst. P25 is composed of anatase, rutile, and amorphous TiO2 particles, and photoexcited electron transfer and subsequent charge separation at the anatase–rutile particle interfaces explain its high photocatalytic efficiency. Herein, we report on a facile and rational hydrothermal treatment of P25 to selectively convert the amorphous component into crystalline TiO2, which is deposited between the original anatase and rutile particles to increase the particle interfaces and thus enhance charge separation. This process produces a new TiO2 exhibiting a considerably enhanced photocatalytic efficiency. This method of synthesizing this TiO2, inspired by a recently burgeoning zeolite design, promises to make TiO2 applications more feasible and effective. 相似文献
49.
Synchrotron x-ray diffraction measurements were performed on liquid SnI4 up to a scattering vector of 25 A(-1), utilizing a horizontal two-axis diffractometer installed at the SPring-8 bending magnet beam line BL04B2 in Japan. An effective method based on the maximum entropy method was devised to transform the measured total structure factor to the reduced radial distribution function. The reliability of the density estimation is discussed. 相似文献
50.
Ajit Kumar Dubey Yoichiro Koyama Nozomu Hashimoto Osamu Fujita 《Proceedings of the Combustion Institute》2021,38(2):1945-1954
Thermo-acoustic oscillations are observed when a flame ignited at open end of a tube propagates towards the closed end due to interaction between unsteady heat release rate fluctuations from flame and acoustic fluctuations. In our past work, it was found that thermo-acoustic instability increases with decreasing diameter from 7.0 cm to 3.0 cm. A recent study in flame propagation in Hele–Shaw cells showed that thermo-acoustic instability is not observed for plate separation less than or equal to 0.4 cm. Thermoacoustic instabilities cannot be observed in very narrow tubes due to excessive damping from the wall. This opens up the possibility of a critical diameter where thermo-acoustic instability would be maximum. In this work we perform flame propagation experiments with diameter of combustion tube in the range 0.5 cm to 3 cm for a fixed length of 70.2 cm. It was found that thermo-acoustic parametric instability begins at lowest laminar burning velocity when the diameter is around 1.0 cm. This diameter is termed as critical diameter. Critical diameter is found to be independent of Lewis number of mixtures. Existence of a critical diameter is thus proved experimentally. Growth rates of primary instability increase with decreasing diameter and show a maximum around the critical diameter and decrease with further decrease in tube diameter. But, growth rates of secondary instability as well as maximum pressure fluctuation amplitude decreases continuously with decreasing diameter. Mechanisms responsible for these observations and existence of a critical diameter are clarified. 相似文献