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41.
Urita K Shiga Y Fujimori T Iiyama T Hattori Y Kanoh H Ohba T Tanaka H Yudasaka M Iijima S Moriguchi I Okino F Endo M Kaneko K 《Journal of the American Chemical Society》2011,133(27):10344-10347
An outstanding compression function for materials preparation exhibited by nanospaces of single-walled carbon nanohorns (SWCNHs) was studied using the B1-to-B2 solid phase transition of KI crystals at 1.9 GPa. High-resolution transmission electron microscopy and synchrotron X-ray diffraction examinations provided evidence that KI nanocrystals doped in the nanotube spaces of SWCNHs at pressures below 0.1 MPa had the super-high-pressure B2 phase structure, which is induced at pressures above 1.9 GPa in bulk KI crystals. This finding of the supercompression function of the carbon nanotubular spaces can lead to the development of a new compression-free route to precious materials whose syntheses require the application of high pressure. 相似文献
42.
Li-Chang Yang Tetsu Yamakawa Sumio Shinoda 《Journal of molecular catalysis. A, Chemical》1998,130(3):409-253
Highly selective formation of methyl acetate has been found possible from methanol alone using the catalyst generated in situ from RuCl3·3H2O and SnCl2 as well as SnX2 (X=F, Br, I). The reaction did not occur in the absence of SnCl2 added and the optimum [Sn]/[Ru] ratio appeared at about 16. The halogen effect showed the order of SnF2>SnCl2>SnBr2>SnI2, which indicates the importance of cationic character of Ru(II) center to facilitate its electrophilic interaction with β-hydrogen of Ru–OCH3 intermediate in the rate-limiting dehydrogenation step. 相似文献
43.
The early stage of hydrolysis and polycondensation of tetraalkoxysilanes (TAOS) in the closed TAOS-C2H5OH-H2O-HCl system at 40°C was studied by the trimethylsilylation technique combined with the gas-liquid and gel permeation chromatographies. Tetramethoxy, tetraethoxy, tetra (n-propoxy) and tetra (n-butoxy) silanes were used as TAOS. The tendencies of variation with time in the distribution and molecular weight of silicate species in the solutions were almost the same in all the TAOS solutions, suggesting that the differences in the alkyl group of the TAOS had little effect on the hydrolysis and polycondensation. 相似文献
44.
Summary We consider an *O-space which is a kind of almost-Hermitian space. There is stated a theorem, that is, in a compact *O-space
a skew-symmetric covariant almost-analytic tensor is closed. From this theorem, we get many important properties of almost-analytic
tensors in an almost-K?hlerian space or a K-space and an interesting result related to the Lie derivative. 相似文献
45.
Tadahiro Minamikawa Seido Ogura Tetsuo Sakka Yukio Ogata Matae Iwasaki 《国际化学动力学杂志》1994,26(5):561-569
Photolysis of CClF2CH2Cl was studied by 147 nm vacuum ultraviolet irradiation. In the presence of NO; CF2CH2, CF2CHCl, and CClF2CN were produced. These products represent three different reaction paths; the molecular dechlorination, molecular dehydrochlorination, and chlorine radical elimination reactions. The reactant pressure and the addition gas (He or NO) pressure effects upon the product yield were studied. © 1994 John Wiley & Sons, Inc. 相似文献
46.
Yoneda K Adachi K Hayami S Maeda Y Katada M Fuyuhiro A Kawata S Kaizaki S 《Chemical communications (Cambridge, England)》2006,(1):45-47
The variable temperature magnetic susceptibility, X-ray crystallography, and M?ssbauer and Raman spectra of a new dinuclear complex-based one-dimensional coordination polymer [[Fe(II)2(NCS)2(mu-bpypz)2](micro-4,4'-bpy)].MeOH demonstrated a steep one-step [HS-HS] to [LS-LS] spin transition. 相似文献
47.
48.
Fan J Yudasaka M Miyawaki J Ajima K Murata K Iijima S 《The journal of physical chemistry. B》2006,110(4):1587-1591
Due to the simplicity of the process, holes in the graphene walls of single-wall carbon nanotubes (SWNTs) and single-wall carbon nanohorns (SWNHs) have often been opened using O2 gas at high temperatures, even though this contaminates the nanotubes with carbonaceous dust (C-dust). To open holes with less C-dust contamination, we found that a slow temperature increase of 1 degrees C/min or less, in air, was effective. We also found that SWNHs having little C-dust could store a large quantity of materials inside the tubes. We infer that the local temperature increase due to the exothermic reaction of combustion may have been suppressed in the slow combustion process, which was effective in reducing the C-dust. 相似文献
49.
Gallate glasses containing no conventional glass formers were obtained in the systems (Na2O, K2O or Cs2O)-Ta2O5---Ga2O3 and (Sr or BaO)-Ta2O5---Ga2O3 by an ordinary crucible-melting technique. The glasses showed high optical transmission in the infrared as well as in the visible region. Infrared spectroscopic analysis suggested that the Ga3+ ions are tetrahedrally coordinated in the glasses. The glass-forming tendency of the melt and the infrared transmission of the glasses are discussed in terms of the glass structure. 相似文献
50.
On the basis of a mathematical model proposed previously [S. Kobayashi, J. Crystal Growth 174 (1997) 163], oxygen precipitation in growing Czochralski (CZ) crystals is analyzed, and the calculated results are compared with experimental data of grown-in defects observed with laser scattering tomography (LST). The behavior of oxygen precipitates is qualitatively very similar to that of grown-in defects, but there are quantitative discrepancies between the calculation and the observation. The formation process of grown-in defects is discussed. 相似文献