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851.
Hirofumi Osada 《Probability Theory and Related Fields》1998,112(1):53-90
We prove the positivity of the self-diffusion matrix of interacting Brownian particles with hard core when the dimension of
the space is greater than or equal to 2. Here the self-diffusion matrix is a coefficient matrix of the diffusive limit of
a tagged particle. We will do this for all activities, z>0, of Gibbs measures; in particular, for large z– the case of high density particles. A typical example of such a particle system is an infinite amount of hard core Brownian
balls.
Received: 22 September 1997 / Revised version: 15 January 1998 相似文献
852.
Hirofumi Yamada 《Letters in Mathematical Physics》1985,9(2):133-137
Tensor product of the basic representation of the extended affine Lie algebra of type A
inf1
sup(1)
is discussed through the vertex operator of {ie133-1}. The highest irreducible component of the tensor product is characterized by the BKP hierarchy. 相似文献
853.
Kanae Hayashi Michinori Tachibana Seizo Okamura 《Journal of polymer science. Part A, Polymer chemistry》1980,18(9):2785-2791
Effects of electron beam irradiation on liquid polybutadiene in n-hexane solution were studied at ?10°C. With irradiation, crosslinking of the polymer and loss of double bond by cyclization took place at the same time. These reactions were retarded by the addition of DPPH or triethylamine which indicated that both radical and cationic mechanisms contributed to this system. 相似文献
854.
The coadsorption of NO and other small gases (H2 and CO) on a polycrystalline Rh filament has been studied by thermal desorption mass spectroscopy, using 15NO. The sample was exposed to a mixture of nitric oxide and other gases with various concentrations of 15NO at room temperature. It is indicated that NO, CO and H2 coadsorbs on the rhodium surface, and NO desorbs as N2 and O2. NO is adsorbed mainly in the dissociation at lower coverage and molecular adsorption becomes dominant at higher coverage. But the amount of desorbed O2 was very small. The chemisorption of CO is affected by the chemisorbed NO. Thermal desorption of hydrogen is detected when the value of P15NO/PCO is very small. The hydrogen adsorbed on the rhodium surface is replaced by NO with a longer exposure time. 相似文献
855.
Seiko Nan'Ya Hirofumi Ishida Ester J. Moiji Yasuo Butsugan Ashok C. Bajji 《Journal of heterocyclic chemistry》1994,31(2):401-403
2-Bromo-3-phenylinden-1-one 2 reacted with phenylthiourea to produce 2-phenylimino-8-phenylindeno[1,2-d]thiazole (heteropentalene) 4 in moderate yield and bis-substituted-indenyl sulfide 5 in low yield. Whereas, from the reaction of 2 with thiourea or its methyl derivative only 5 was obtained in moderate yield. Another brominated compound, dibromoacetylbenzophenone and several primary amines afforded iminoindanone derivatives 6 . 相似文献
856.
Akitomo Tachibana 《International journal of quantum chemistry》1994,49(5):625-637
It is demonstrated that in the plasma state of the homogeneous electron gas the time-reversal electron pair is stabilized. This nature survives even in the inhomogeneous electron gas, where the Bragg reflection at the lattice points is not necessarily a stumbling block for electron pairing. Indeed, a critical radius rc exists around the lattice point, outside of which the time-reversal scattering state of the electron pair is guaranteed. The critical radius rc has an intrinsic importance as a measure of the coherence length ζ of the Cooper pair that exhibits the time-reversal symmetry. © 1994 John Wiley & Sons, Inc. 相似文献
857.
Seto Takafumi Kawakami Yuji Suzuki Nobuyasu Hirasawa Makoto Kano Seisuke Aya Nobuhiro Sasaki Shinya Shimura Hirofumi 《Journal of nanoparticle research》2001,3(2-3):185-191
Nanometer-sized particles of silicon and titanium oxide were generated by irradiating solid targets using a nanosecond pulsed-Nd : YAG laser in a low pressure atmosphere. A low pressure differential mobility analyzer (LP-DMA) was used to classify the size of the generated particles. The LP-DMA and electron microscopes (SEM and TEM) were used to measure the change in the size distribution and morphology of the generated particles with laser power density and system pressure. The size distribution of both silicon and titanium oxide ranged from two to one hundred nanometers in diameter depending on the laser power density and pressure. From the high resolution TEM observation and electron diffraction, it was found that the generated titanium oxide nanoparticles were composed of a core of faceted metallic single crystals with an oxide layer 'shell. 相似文献
858.
859.
Gerry Bagtasa Cheng Liu Nobuo Takeuchi Hiroaki Kuze Suekazu Naito Akihiro Sone Hirofumi Kan 《Optical Review》2007,14(1):39-47
Lidar data observed by two continuously operated portable automated lidar (PAL) systems and images from the visible and thermal
infrared channels of the advanced very high resolution radiometer (AVHRR) sensor on board the noaa16 satellite are employed for the characterization of cloud heights and cloud types. The PAL systems are located in Chiba
and Ichihara city areas, separated by approximately 10 km. Measurements from October 2003 to March 2005 reveal that monthly
averages of cloud base height and cloud cover ratio show good agreement between the two sites. The characteristics of the
vertical (Chiba) and slant (Ichihara) measurements are also discussed. The PAL data are used to adjust threshold values of
a cloud-type classification method in split-window data of noaa16-AVHRR. Comparisons between the lidar signals and the cloud classification results from the concurrent AVHRR images show
that the classification method can reasonably be applied to this mid-latitude case, although the split-window technique was
originally developed for tropical clouds. 相似文献
860.
Oxidative addition of H2 to Ni(PH3)2 was theoretically studied as a prototype of nickel-catalyzed sigma-bond activation reaction, where CASSCF, CASPT2, CCSD(T), broken symmetry (Bs) MP2 to MP4(SDTQ), and DFT methods were employed. The CASPT2 method yields a reliable potential energy curve (PEC) when the active space consists of 10 electrons and 10 orbitals including five outer 3d' orbitals. The CCSD(T) method presents almost the same PEC as the CASPT2-calculated one, when either the ANO or the cc-pVTZ basis set is used for Ni. Bs-MP4(SDTQ)-calculated PEC is similar to those calculated by the CASPT2/ANO method, while the PEC is not smooth around the transition state. In the DFT calculation, ANO, cc-pVTZ, and triple-zeta quality basis sets (SDB) with Stuttgart-Dresden-Bonn effective core potentials (ECPs) must be used for Ni. The DFT-calculated reaction energy is somewhat smaller than the CASPT2- and CCSD(T)-calculated values, while B3PW91 and mPW1PW91 present moderately better energy changes than BLYP, B1LYP, and B3LYP. Oxidative addition of MeCN to Ni(PH3)2 was investigated by the DFT(B3PW91) and CCSD(T) methods. Almost the same activation barrier was calculated by these methods, when cc-pVTZ was employed for Ni. However, the DFT method moderately underestimates the binding energy of the reactant complex and the reaction energy compared to the CCSD(T) method. This oxidative addition exhibits interesting characteristic features, as follows: The barrier height relative to infinite separation is lower, and the product is more stable than those of the oxidative addition of C2H6. These differences are discussed in detail in terms of Ni-Me and Ni-CN bond energies and the participation of the CN pi* orbital to stabilization interaction in the transition state. 相似文献