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131.
The synthesis and spectroscopic characterization of the title complexes correspond to isoelectronic system of o-quinodi-methane complex are described. 相似文献
132.
The room temperature crystallographic properties of distorted perovskite-type system BaPb1-xBixO3 were examined by using X-ray diffraction analysis. In addition, structural temperature changes were investigated for superconducting BaPb0.75Bi0.25O3 crystals with Tc=11.4K. It was found that the room temperature structure of BaPb1-xBixO3 has an orthorhombic symmetry in the range of O≤×?0.9 and a monoclinic one in 0.9?×≤1, and that superconducting BaPb0.75Bi0.25O3 shows a structural transition from an orthorhombic to a monoclinic phase at about 160K. 相似文献
133.
Hiroji Oda Mitsuyoshi Sato Yoshitomi Morizawa Koichiro Oshima Hitosi Nozaki 《Tetrahedron》1985,41(16):3257-3268
Dimethylphenylsilyl group is removed from a vinyl carbon with tetrabutylammonium fluoride. The presence of phenyl group on silicon atom plays a critical role. The cleavage of allyldimethylsilyl- and alkoxydimethylsilyl groups also proceeds very easily. 相似文献
134.
On irradiation arylcarbothioamides (1) undergo, in the absence of oxygen, the Paterno-Büchi reaction with olefins followed by cleavage, whereas under aerobic conditions the photoreaction proceeds to give 4 and 5 probably via nitrile sulfide intermediates. 相似文献
135.
136.
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
137.
Hiroshi Oda Takeshi Hanami Takashi Iwashita Miki Kojima Masayoshi Itoh Yoshihide Hayashizaki 《Tetrahedron》2007,63(51):12747-12753
A novel C-deoxyribonucleoside bearing 2-aminopyrrole was synthesized. The C-glycosidation between deoxyribose and pyrrole ring was carried out using palladium-catalyzed Heck coupling in the presence of excess amount of lithium chloride as an additive. The synthesized aminopyrrole nucleoside is expected to become a promising counterpart of the artificial nucleoside pair. 相似文献
138.
M. Hirsch O. Kadowaki H. V. Klapdor-Kleingrothaus K. Muto T. Oda 《Zeitschrift für Physik A Hadrons and Nuclei》1995,352(1):33-45
Reliable calculations of nuclear matrix elements are a prerequisite for the determination of the effective neutrino mass and other particle physics parameters from neutrinoless double beta decay. Here, the operator expansion method is improved by including Coulomb, tensor and central interactions simultaneously. Furthermore, the formalism of the OEM is extended to those matrix elements necessary to extract the right-handed parameters and from 0 decay. OEM includes the dependence of the nuclear matrix elements on the intermediate states implicitly and can therefore be understood as a step beyond the closure approximation. Numerical studies are carried out for the isotope76Ge combining the OEM expressions with ground-state wave functions calculated within a proton-neutron quasiparticle Random Phase Approximation (pn-QRPA) model. The influence and relative importance of central, tensor and Coulomb interactions is investigated. Within the OEM, contributions from the Coulomb force are found to be negligible in 0 decay, while the tensor force leads to a moderate change of the results, of the order of (10–30)%, giving a better agreement between sets of calculations which employ different NN-interactions. Generally, results of the OEM+QRPA calculation are similar to previous calculations of 0 decay matrix elements, indicating that 0 decay is not sensitive to model approximations and might therefore be more accurately calculated than the strongly suppressed 2 decay matrix elements. 相似文献
139.
Ken-ichi Okamoto Norikazu Oda Akira Itaya Shigekazu Kusabayashi 《Chemical physics letters》1975,35(4):483-486
Magnetic fields were found to increase the photocurrent in poly-N-vinylcarbazole (PVCz) films by up to 5–6% at 1 kG. This positive magnetic field effect was sensitive to both applied voltage and temperature, and was enhanced with dimethyl-terephthalate (DMTP) doping by a factor of two. Magnetic fields were also found to increase the prompt exciplex fluorescence of PVCz films doped with DMTP by up to 2% at 500 G. The observations made clear that a carrier generation process via an exciplex state has an important role in photo-carrier generation even in undoped PVCz films. 相似文献
140.
[reaction: see text] 1,3-Butadiene reacted with chlorosilanes and Grignard reagents at 20 degrees C in the presence of a catalytic amount of Pd(acac)(2) to give disilylated dimers 2 regioselectively, which have two silyl groups (R(3)Si) at the 3- and 8-positions of a 1,6-octadiene skeleton. When phenyl- or allyl-substituted chlorosilanes were used, coupling product was obtained stereo- as well as regioselectively, giving rise to only (E)-olefins. It is proposed that Pd-ate complexes play important roles in both C-Si bond-forming processes. 相似文献