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111.
Kenji Kawada Akinori Arimura Tatsuo Tsuri Masahiro Fuji Tadafumi Komurasaki Shuji Yonezawa Akira Kugimiya Nobuhiro Haga Susumu Mitsumori Masanao Inagaki Takuji Nakatani Yoshinori Tamura Shozo Takechi Teruhiko Taishi Junji Kishino Mitsuaki Ohtani 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》1998,110(7):1015-1017
112.
The etching studies were made on flux grown phenakite (Be2SiO4) single crystals to elucidate the twinning phenomenon and the growth mechanism. The sharp and distinct etch pits and the twin boundaries were successfully obtained after the hydrothermal etching. From the etching and the X-ray precession experiments, it was conjectured that the phenakite had an inversion twin along the c axis. The twinning should be originated during the earlier stage of growth where the dendritic and acicular crystals were grown and thereafter the twinned crystals grew to the prismatic crystals during the latter stage with decreasing the temperature. 相似文献
113.
Triptycenes carrying a leaving group at one of the bridgehead carbons afforded the title compound in good to moderate yields when irradiated with a low-pressure Hg lamp. The tropylium ion and the strong CT-complexes of the hydrocarbon were prepared. 相似文献
114.
Shin-ichi Hirashima Kosuke Nakashima Yuki Fujino Ryoga Arai Takaaki Sakai Masahiro Kawada Yuji Koseki Miho Murahashi Norihiro Tada Akichika Itoh Tsuyoshi Miura 《Tetrahedron letters》2014
A diaminomethylenemalononitrile organocatalyst with a cinchona motif efficiently promotes the enantioselective conjugate addition of acetylacetone to various nitroalkenes to yield the corresponding addition products in high to excellent yields with up to 89% ee. 相似文献
115.
Shibayama M Kawada H Kume T Matsunaga T Iwai H Sano T Osaka N Miyazaki S Okabe S Endo H 《The Journal of chemical physics》2007,127(14):144507
The microscopic structure of shear-induced gels for a mixed solution of 2-hydroxyethyl cellulose and nanometer-size spherical droplets has been investigated by in situ small-angle neutron scattering (SANS) with a Couette geometry as a function of shear rate gamma. With increasing gamma, the viscosity increased rapidly at gamma approximately 4.0 s(-1), followed by a shear thinning. After cessation of shear, the system exhibited an extraordinarily large steady viscosity. This phenomenon was observed as a shear-induced sol-gel transition. Real-time SANS measurements showed an increase in the scattering intensity exclusively at low scattering angle region. However, neither orientation of polymer chains nor droplet deformation was detected and the SANS patterns remained isotropic irrespective of gamma. It took about a few days for the gel to recover its original sol state. A possible mechanism of gelation is proposed from the viewpoint of shear-induced percolation transition. 相似文献
116.
Sugi K Itaya N Katsura T Igi M Yamazaki S Ishibashi T Yamaoka T Kawada Y Tagami Y Otsuki M Ohshima T 《Chemical & pharmaceutical bulletin》2000,48(4):529-536
Paroxetine, a potent and selective inhibitor of 5-hydroxytryptamine (serotonin) uptake, was prepared through a piperidine derivative, which was reported to be one of the paroxetine metabolites in humans. Thus, the piperidine derivative was converted to its N-tert-butoxycarbonyl (N-Boc) derivative, which was then converted to N-Boc paroxetine. Paroxetine hydrochloride propan-2-ol (isopropyl alcohol (IPA)) solvate crystals were directly obtained from the N-Boc paroxetine by adding hydrogen chloride to the N-Boc paroxetine IPA solution. The amount of IPA content in the crystals was reduced by drying with a continuous change of powder X-ray diffraction patterns. Other characterizations of the solvate crystals were also conducted. 相似文献
117.
Xenon difluoride reacts smootlhy with various steroid silyl enol ethers in the absence of any acid catalyst to afford stereoselectively α-oriented α-fluoroketones in good yields while iodotoluene difluoride reacts rather sluggishly with these silyl enol ethers to competitively produce β-oriented α-fluoro ketones, elimination and other nucleophilic substitution products. The observed stereochemical contrast clearly suggests an electrophilic and nucleophilic mechanism for these reactions, respectively. 相似文献
118.
Y. Satou K. Tshoo H. Bhang S. Choi J. W. Hwang T. Nakamura Y. Kondo Y. Nakayama N. Kobayashi K. N. Tanaka S. Deguchi Y. Kawada N. Tanaka T. Motobayashi H. Sakurai H. Otsu N. Aoi S. Takeuchi K. Yoneda Y. Togano M. Ishihara S. Shimoura T. Kobayashi M. Matsushita T. Honda T. Sumikama Y. Miyashita K. Yoshinaga N. A. Orr F. M. Marques J. Gibelin F. Delaunay D. Sohler T. Zheng Z. H. Li Z. X. Cao 《Few-Body Systems》2013,54(1-4):287-290
The neutron-rich oxygen isotope 23O has been investigated via proton inelastic scattering on a liquid hydrogen target at 63.5 MeV/nucleon. The invariant mass method in inverse kinematics was employed to reconstruct the energy spectrum. A sharp resonance state was observed at 42(5) keV above the neutron threshold. A comparison of the differential cross section leading to this state with a microscopic DWBA calculation allowed a J π assignment of 5/2+ for this state. 相似文献
119.
120.