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91.
Takashi Ogihara Nobuyasu Mizutani Masanori Kato 《Journal of the American Ceramic Society》1989,72(3):421-426
Monodispersed ZrO2 seed particles which were prepared by hydrolysis of zirconium alkoxide solutions were allowed to grow by further addition of zirconium alkoxide and water under conditions in which new particles do not nucleate and grow. The particle growth mechanism is presumed to be a surface reaction in which the rate-determining step is a first-order polynuclearlayer growth mechanism. With this method of powder preparation, it is possible to precisely control the particle size, and it may be useful for applications in ceramic processing. 相似文献
92.
CARBON-BASED MATERIALS have been regardedas one of the most important materials in nano-technology.Not only nanotubes and fullerenes but alsoa new form of carbon incorporating distinct graphiticconfigurations in amorphous carbon networks hasrecently attracted extensive interests in order toaccomplish high performances by combining diversephysical properties which arise from carbon structuresfl,2].In particular,the establishment of functionallyhybridized carbon systems with a thin film f… 相似文献
93.
Masahiro Fujimoto Mamoru Ishida Akihiko Fujii Yoshimine Sakamoto Norifumi Fujita Seiji Shinkai Masanori Ozaki 《Synthetic Metals》2009,159(9-10):871-874
The molecular alignment of polydiacetylene (PDA) derivatives and their optical and electrical properties of thin films based on PDA derivatives have been studied. The PDA derivatives were aligned depending on the direction of applied shear stress in the film. From measurements of the polarized absorption and current–voltage characteristics, the optical and electrical anisotropies have been observed, that was discussed by taking the PDA main chain alignment into consideration. 相似文献
94.
95.
NiInGe ohmic contact materials, which are attractive to use in future GaAs devices, were previously developed in our laboratories.
Although the NiInGe contacts provided low contact resistances of about 0.3 Ω-mm and excellent thermal stability, further reduction
of the contact resistance (RC) of the NiInGe contacts was mandatory to use these contacts in submicron devices. In this paper, the microstructural parameters,
which influence the RC values, were investigated by correlating the RC values with the microstructure at the interface between the contact materials and the GaAs substrate. The RC values of the NiInGe contacts were found to depend strongly on the volume fraction and the In concentration (x) of the InxGa1−xAs compound semiconductor layers, which were formed at the metal/GaAs interface. Both the volume fraction and the In concentration
of the InxGa1−xAs layers were found to depend on the thickness of the In layer used in the NiInGe contact and the annealing temperature to
form the ohmic contact. A RC value of 0.18 Ω-mm was obtained for the Ni (18 nm)/In (13 nm)/Ge (30 nm) contact (where a slash “/” indicates the deposition
sequence) after annealing at temperature of 650°C for 5 sec. 相似文献
96.
The entropy and the mutual entropy for states and channels are totally studied in general quantum systems described byC*-algebras. In particular, we discuss the relations among theS-entropy and the mutual entropy introduced by Ohya and the Connes-Narnhofer-Thirring entropy. 相似文献
97.
98.
Any solution for an inverse heat conduction problem makes the estimation of surface temperature and surface heat flux worsen in the case where these values behave like a triangular shape change with time. In order to compensate for this defect, Monde and colleagues, who succeeded in obtaining analytical inverse solutions using the Laplace transform technique, introduce a new idea where these changes over the entire measurement time can be split into several parts depending on the behavior. Therefore, an approximate equation to trace the measured temperature change can be derived, resulting in good estimation of surface temperature and surface heat flux even in the case of the triangular shape change and sharp change. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(7): 630–638, 2003; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10117 相似文献
99.
M. Hangyo M. Tani T. Nagashima 《Journal of Infrared, Millimeter and Terahertz Waves》2005,26(12):1661-1690
Recent development of the terahertz time domain spectroscopy (THz-TDS) and its application to solids have been reviewed. This spectroscopy is unique in that the time-domain wave forms are measured at first and the complex optical constants are deduced directly by the Fourier transformation of them without resort to the Kramers-Kronig analysis. Various types of the THz-TDS systems are briefly described. Applications of the THz-TDS to various solids, i.e., semiconductors, superconductors, polymers, photonic crystals, and so on are also presented to demonstrate how widely this spectroscopy is applicable to characterization of solids. 相似文献
100.
Observations of high temperature impinging-jet boiling phenomena 总被引:1,自引:0,他引:1
Peter Lloyd Woodfield Masanori Monde Aloke Kumar Mozumder 《International Journal of Heat and Mass Transfer》2005,48(10):2032-2041
A high-speed video camera and microphone were used to capture the flow behavior and boiling sound of a free-surface water jet impinging on a high temperature surface during quench cooling. It was found that depending on the superheat of the surface considerably different flow patterns appeared. For cases where the initial surface temperature was above about 300 °C an almost explosive pattern appeared. This was in contrast to slightly lower temperatures where a liquid sheet flow structure was apparent. The change in phenomena was accompanied by a sudden change in the boiling sound and an increase in the heat transfer rate. 相似文献