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111.
Takashi Uchino Tetsuo Sakka Matae Iwasaki 《Journal of the American Ceramic Society》1991,74(2):306-313
Infrared spectra of thin films (a few micrometers) of hydrated sodium silicate glasses after heating at temperatures from 100° to 400°C were measured in the spectral region from 400 to 4300 cm−1 . Also, Raman spectra of hydrated glasses were measured in the region from 100 to 1400 cm−1 . Water molecules in hydrated glasses were classified into three types by the bonding configuration: water molecules interacting with Si–OH groups, nonbridging oxygens, and bridging oxygens. On the basis of the fundamental bands observed here, we calculated the wave numbers of the combination-overtone bands of water molecules and SiOH groups in hydrated glasses. The calculated wave numbers satisfactorily agreed with observed wave numbers in the nearinfrared region. 相似文献
112.
113.
We calculate the thermal conductivity of solid
3
He in U2D2 phase. In this system, magnons are the dominant heat carriers. The experiment by Feng et al. shows that scattering magnon by some kind of magnetic defects becomes important at low temperature. We suppose the defects are the magnetic plane defects (MPD) which are originated by lattice dislocation and calculate the thermal conductivity with Kapitza Resistance Model (KRM). 相似文献
114.
Iwao Hachiya Tetsuo Koyano Kiyotaka Sato 《Journal of the American Oil Chemists' Society》1989,66(12):1757-1762
Effects of seeding of fat crystals on the crystallization kinetics of cocoa butter and dark chocolate were examined with a
rotational viscometer. The seed crystals employed were cocoa butter, 1,3-distearoyl-2-oleoylglycerol (SOS), 1,3-dibehenoyl-2-oleoylglycerol
(BOB) and 1,2,3-tristearoylglycerol (SSS). The seed powders were prepared by pulverization below —50°C, the dimensions being
in a range from 20–70 μm. Particular attention was paid to the influence of polymorphism of the seed crystal. We found that
all of the above seed materials accelerated the crystallization, the degree of acceleration being in a following order; SOS
(β
1) > cocoa butter (Form V) > SOS (a mixture ofβ’ andβ
2) > BOB (β
2) > BOB (pseudo-β’) > SSS (β). Precise measurements of the crystallization kinetics showed that the most influential factors in the seeding
effects are the physical properties of the seed materials—above all, thermodynamic stability, and similarity in the crystal
structure to cocoa butter are the most determinative. 相似文献
115.
Electrophoretic deposition (EPD) was used to form ZnO deposits. ZnO with an average particle size of 40 nm was dispersed in water with the addition of an appropriate amount of anionic polyelectrolyte. Uniform and bubble-free ZnO deposits have been obtained via EPD on a zinc anode in an aqueous suspension. The obtained deposits showed good sinterability. 相似文献
116.
Study on explosion characteristics of natural gas and methane in semi-open space for the HTTR hydrogen production system 总被引:1,自引:0,他引:1
Yoshitomo Inaba Tetsuo Nishihara Mark A Groethe Yoshikazu Nitta 《Nuclear Engineering and Design》2004,232(1):111-119
It is important to grasp the explosion characteristics of object gases: natural gas and methane, in order to evaluate the influence of a gas explosion accident in the HTTR hydrogen production system on the reactor. Thus, we carried out explosion experiments of the object gases in semi-open space, and verified a numerical analysis code for the simulation of the explosion accident. It was confirmed that NG–air mixture or methane-air mixture in semi-open space did not result in DDT although 10 g of C-4 explosive was used as an ignition source, and the numerical results agreed relatively with the experimental results. As a result, we could have the prospects for predicting the influence of the explosion accident on the reactor. 相似文献
117.
Jin-Kook Lee Katsuhiko Fujida Tetsuo Tsutsui Mi-Ra Kim 《Solar Energy Materials & Solar Cells》2007,91(10):892-896
Organic solar cells made from bi-layer thin-film heterojunctions having poly((2-methoxy-5-(2′-ethylhexyloxy)-p-phenylene)vinylene) (MEH-PPV) as an electron donor and fulleropyrrolidine derivatives as an electron acceptor were investigated. We synthesized soluble fulleropyrrolidine derivatives substituted different chain lengths for the organic solar cell. Due to the high solubility and sufficiently long chain length of fulleropyrrolidine derivatives, though those are monomers, a thin film (about 80–90 nm) could be fabricated individually by the spin-coating method. The fill factor of the bi-layer device was achieved to be 0.46, which is higher than that of the single-layer device by a polymer/fulleropyrrolidine derivative blend film of 0.37, due to the decrease of the recombination. 相似文献
118.
Theoretical procedures of first-principles calculations of phase stability and phase equilibria are summarized. The present
scheme is shown to be able to reproduce the transition temperatures with surprisingly high accuracy for Fe−Pd and Fe−Pt systems.
The main emphasis of the present report is placed on the extension of the first-principles calculation to transition dynamics
calculations. This is performed by combining the cluster variation method with the phase-field method via a coarse graining
operation. The time evolution process of antiphase boundaries associated with L10 ordering for Fe−Pd system is demonstrated.
This paper was presented at the International Symposium on User Aspects of Phase Diagrams, Materials Solutions Conference
and Exposition, Columbus, Ohio, 18–20 October, 2004. 相似文献
119.
The diversity of human immunodeficiency virus (HIV) in vivo has been reported. In this article, we propose a cellular automata
(CA) model describing the interactions between the immune system and HIV, and examine the effect of the diversity of these
interactions. The novel aspects of our CA model are that it not only considers four states (HIV, virgin, dead, infect) but
also the diversity exhibited by both HIV and T cells. We simulated maximum diversities for these states by simulating CA on
a computer. The model revealed that increased diversity had the effect of increasing the HIV population and simulation steps.
In addition, we observed that the CA model accurately reflects the occurrence of infection, incubation period, and the development
of AIDS. The CA model demonstrated that the diversity of the virus is the major factor affecting the success rate of the escape
of HIV from the immune response.
This work was presented in part at the 10th International Symposium on Artificial Life and Robotics, Oita, Japan, February
4–6, 2005 相似文献
120.
Tetsuo Mohri Takayuki Nakahara Satoshi Takizawa Tomoo Suzuki 《Journal of Alloys and Compounds》1995,220(1-2):1-7
The cluster variation method of equilibrium thermodynamics is employed to calculate the Ll0-disorder phase diagram. The stability analysis based on the second-order derivative of the free energy functional with respect to the deviation of correlation functions from their equilibrium values yields the 100 instability locus in the phase diagram. The time evolution of cluster probabilities at the phase transition is investigated on the basis of the path probability method of non-equilibrium statistical mechanics. Thereby the synthetic study of thermodynamics and kinetics based on the cluster variation method and the path probability method is attempted. It is shown that the fluctuation is necessary to drive the ordering reaction above the instability temperature, whereas the spinodal-like ordering transition takes place below the instability temperature. The extension of the present study of a spin system to an alloy system is briefly discussed and a critical problem to be settled is pointed out. 相似文献