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101.
102.
103.
Makoto Kobayashi Akihiko Sato Yugo Tanaka Hisanori Shinohara Hiroyasu Sato 《应用有机金属化学》1993,7(5):303-309
Photodissociation of trimethylaluminum [Al(CH3)3] adsorbed on a silica (SiO2) substrate at 110 K has been studied by multiphoton ionization time-of-flight mass spectrometry. Translational energy distributions of aluminum and AlCH3 fragments can be fitted with a composition of two Maxwell–Boltzmann distributions. The two components are attributed to different environments of photodissociating parent molecules in the multilayer. 相似文献
104.
Hiroyasu Sato 《应用有机金属化学》1989,3(5):363-382
Photochemistry of organometallic compounds achieves a marriage of a rich variety of organometallic chemistry and the full potential of electronically excited states of molecules. The application of lasers as light sources adds a great many new features to these studies, which cannot be attained by other means, because lasers provide light of such a high quality, e.g. a high-intensity, energetic (i.e. wavelength) purity, a high degree of coherence, and a high spatial and temporal resolution. Laser photochemistry of organometallic compounds, such as laser photochemical vapor deposition (LPCVD), laser ablation, and photochemical dry etching, forms the basis of many important industrial processes which sustain the present-day microelectronics industries. Lasers are used not only to photodissociate organometallic molecules, but to monitor the reaction steps by probing the starting material, chemical intermediate, or final product by many laser-based spectroscopic methods. Although it is a very young area of science (the first laser was operated in 1960), this research area is now really ebullient, as a result of strong interest from both the fundamental and the practical sides. Laser photochemistry of organometallic compounds extends a wide and fertile research frontier, full of challenge and novel possibilities. In the present review, the present status of laser (ultraviolet and visible) photochemistry of organometallic compounds related to these industrial applications is briefly reviewed, with special emphasis on the basic studies of the relevant photochemistry and their relationship to photochemical processes on solid surfaces. 相似文献
105.
Parameters G
ij
in the Kirkwood-Buff theory of solution were calculated for binary fluid mixtures of Lennard-Jones (LJ) 6–12 molecules by using the Percus-Yevick theory. Calculations were carried out for various parameters in the LJ potential. Under the Lorentz-Berthelot rules, G
11
and/or G
22
-composition curves do not show a maximum for any parameters in the LJ potential. When the intermolecular interaction between different species becomes much weaker than that expected from the Berthelot rule, G
11
and G
22
show a maximum and G
12
a minimum. The pressure effect on G
ij
was examined and calculations at constant pressure were also carried out. G
ij
is almost independent of the pressure when the ratio of the molecular volume of two components is in the range 1.0 to 2.5. Comparison was made between experimental and calculated G
ij
for cyclohexane-2,3-dimethylbutane and acetonitrile-toluene systems. For the latter system, the quantitative agreement between the calculated and experimental could not be obtained but showed that the characteristics of G
ij
-composition curves can be explained qualitatively by using the PY theory.Adjunct Associate Professor of Institute for Molecular Science (April 1982–March 1984) 相似文献
106.
Hiroyasu Izeki 《Transactions of the American Mathematical Society》1996,348(12):4939-4964
We consider deformations of flat conformal structures from a viewpoint of connected sum decomposition of conformally flat manifolds.
107.
Kenji Kinoshita Yasuo Shida Chiseko Sakuma Mutsuo Ishizaki Koichi Kiso Osamu Shikino Hiroyasu Ito Masatoshi Morita Takafumi Ochi Toshikazu Kaise 《应用有机金属化学》2005,19(2):287-293
Diphenylarsinic acid (DPAA) and phenylarsonic acid (PAA), which were degradation products of organoarsenic chemical warfare agents used as sternutatory gas, were detected in the well water at Kamisu, Ibaraki Prefecture, Japan. The standard material of DPAA was synthesized with aqueous arsenic acid and phenylhydrazine in order to determine organic arsenic compounds in well water. The DPAA showed a protonated ion at m/z 263 [M + H]+ and a loss of H2O ion at m/z 245 [M + H ? H2O]+ from protonated ion by the electrospray ionization time‐of‐flight mass spectrometry. The quantitative analysis of DPAA and PAA was performed by high‐performance liquid chromatography inductively coupled plasma mass spectrometry and the system worked well for limpid liquid samples such as well water. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
108.
Andrew J. Yencha Hiroyasu Kubota Tsutomu Fukuyama Tamotsu Kondow Kozo Kuchitsu 《Journal of Electron Spectroscopy and Related Phenomena》1981,23(3):431-440
The Penning ionization electron spectra (PIES) and ultraviolet photoelectron spectra (UPS) of ammonia and water molecules condensed on a cold metal substrate have been measured using thermal He*(23S, 21S) metastable atoms and He(I) (58.4 nm) photons. The shifts of the observed positions of the PIES peaks relative to those of the UPS peaks in the condensed phase are roughly equal to the corresponding shifts in the gas phase. The relative intensities of the 3a1 and 1e orbital peaks are reversed in the PIES and UPS for both gaseous and condensed ammonia; the origin of this reversal is interpreted as the difference between the interactions with metastable atoms and photons. On the other hand, the relative intensities of the 3a1 orbital peak in the PIES and UPS for condensed water decrease as compared to the gas-phase spectra. This implies participation of the 3a1 orbital of water in the hydrogen bonding. 相似文献
109.
110.
Morris W Doonan CJ Furukawa H Banerjee R Yaghi OM 《Journal of the American Chemical Society》2008,130(38):12626-12627
A new crystalline zeolitic imidazolate framework, ZIF-90, was prepared from zinc(II) nitrate and imidazolate-2-carboxyaldehyde (ICA) and found to have the sodalite-type topology. Its 3D porous framework has an aperture of 3.5 A and a pore size of 11.2 A. The pores are decorated by the aldehyde functionality of ICA which has allowed its transformation to the alcohol functionality by reduction with NaBH4 and its conversion to imine functionality by reaction with ethanolamine to give ZIF-91 and ZIF-92, respectively. The N2 adsorption isotherm of ZIF-90 shows a highly porous material with calculated Langmuir and BET surface areas of 1320 and 1270 m2 g(-1). Both functionalized ZIFs retained high crystallinity and in addition ZIF-91 maintained permanent porosity (surface areas: 1070 and 1010 m2 g(-1)). 相似文献