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排序方式: 共有859条查询结果,搜索用时 31 毫秒
1.
2.
Shingo Hirano Akio Kawabata Masaru Yoshinaka Ken Hirota Osamu Yamaguchi 《Journal of the American Ceramic Society》1995,78(5):1414-1416
A compound denoted as (Ce0.75 Zr0.25 )O2 (Ce, ZrO8 ) is formed near room temperature from cerium and zirconium nitrates using hydrazine monohydrate. It has a cubic unit cell with a = 0.5342 nm. Characterization of powders heated to various temperatures at 10°C/min demonstrates that the specific surface area does not decrease below 20 mVg until >1000°C. 相似文献
3.
Masaru Kadoshima Masahiko HirataniYasuhiro Shimamoto Kazuyoshi ToriiHiroshi Miki Shinichiro KimuraToshihide Nabatame 《Thin solid films》2003,424(2):224-228
We investigated rutile-type titanium dioxide (TiO2) films for possible use as a high-k gate insulator. The TiO2 thin films were directly deposited on Si substrates using a RF magnetron sputtering method with a sintered oxide target. A single phase of rutile-type TiO2 whose dielectric constant of approximately 75 was obtained when the film was deposited in an inert gas atmosphere and annealed at 800 °C in an oxidizing gas atmosphere. The oxygen ions were deficient in the as-deposited film, and consequently, a sufficient oxygen supply was needed to crystallize the film to a single phase of rutile during the post-annealing. However, the interfacial SiO2 layer between the TiO2 and the Si substrate simultaneously grew thicker than 2 nm. As the interfacial SiO2 grew, the leakage current was decreased and the equivalent oxide thickness was increased, in the Au/rutile-type TiO2/Si capacitor. Therefore, we concluded that the growth of the interfacial SiO2 layer thicker than 2 nm is inevitable to form the single phase of rutile-type TiO2 and to decrease the leakage. 相似文献
4.
Infrared (IR) detecting elements were prepared using positive temperature coefficient (PTC) thermistors with large temperature
coefficients of resistivity (α). Their compositions were denoted as Ba1−x
Sr
x
Nb0.003Ti0.997O3 + 1 mol % TiO2 + 0.07 mol %MnO (x=0, 0.2), and their temperature coefficients of resistivity were 78 and 50% K−1, respectively. Their IR sensing properties were measured under the self-regulating heating conditions, and were compared
with those of a detector with small α (18 % K−1). It was shown that large α was effective for controlling the element temperature by self-regulating heating and for improving
sensitivity. The responsivity,R
v
of the element withx=0.2 was 980 VW−1, and was as large as those of pyroelectric detectors. Expressions which normalize the sensitivity and the thermal time constant
were derived. From these expressions, criteria for improving some IR sensing properties were obtained. 相似文献
5.
The gelation mechanism of agarose and κ-carrageenan aqueous solutions was investigated by using polarized light scattering and X-ray diffraction techniques in terms of the liquid-liquid phase separation. When an incident beam of He-Ne gas laser was directed to the gel prepared by quenching the agarose solution, the logarithm of scattered intensity increased linearly in the initial stage and tended to deviate from this linear relationship in the latter stage. If the linear increase in the initial stage could be analyzed within the framework of the linear theory of spinodal decomposition proposed by Cahn, the phase diagram indicated that the gelation is attributed to the phase separation due to the concentration fluctuation of solution. Furthermore, in the later stage showing the deviation of the linear relationship, light scattering under Hv polarization condition showed a X-type pattern indicating the existence of optically anisotropic rods, the optical axes being parallel or perpendicular with respect to the rod axis. In spite of the existence of the rods, no crystallites were confirmed by the corresponding X-ray diffraction and DSC measurements. For κ-carrageenan solutions, the logarithm of scattered intensity against time showed a constant value. This indicated that the gelation of κ-carrageenan solutions is independent of liquid-liquid phase separation but is due to the rapid formation of cross-linking points. Accordingly it turns out that the small difference of chemical structure between agarose and κ-carrageenan causes quite different gelation mechanism. 相似文献
6.
Nobuo Masaki Tetsuo Yoshida Masaru Miyagawa Iawo Ohshima Kikuo Matsuzawa 《Electrical Engineering in Japan》1992,112(2):58-70
A second-generation model of cubicletype gas-insulated switchgear (C-GIS) with composite insulation incorporating SF6 gas has been developed. The design does not require a gas process in field assembly; it has high reliability and its installation is more rapid; and a further reduction in size is achieved. The design principles are described in detail. 相似文献
7.
Masaru Sanada 《Microelectronics Reliability》1993,33(7)
A new technique for failure analysis of LSI with multi metal layers is described. There is a fabrication technique to form a big and optional window on upper layers using Nd-YAG laser without destroying any electrical function, and to approach the failure point through this window. The failure analysis procedure based on logical flow is presented. Fabrication technique is located in part of this procedure which consists of four steps. Two difficult reasons for approaching the failure point without fabrication technique are described. This difficulty results from line composition and line width. The fabrication procedure using Nd-YAG laser is reported. This procedure is to cover the chip surface with photo resist, and form a big and optional size window on upper layer with laser beam, and finally expose the purposed layer. Three failure analysis examples using this technique are introduced: unformed contact falure mode, Si-noduled failure mode, and isolation destroying failure mode. 相似文献
8.
Masaru Itoh 《The Structural Design of Tall and Special Buildings》1992,1(2):119-132
This paper summarizes the results of the wind design carried out for the Act Tower building in Japan. Wind tunnel tests were performed in order to estimate the building response for different wind directions. Undesirable building motion perceived by building occupants is also studied and antivibration systems have been installed to solve this problem. 相似文献
9.
Yoshinobu Ohara Takeshi Taki Masaru Miyayama Hiroaki Yanagida 《Journal of Materials Science》1996,31(20):5327-5332
The sintering of fibrous BaTiO3 powder particles was investigated. Special emphasis was given to the role of particle orientation in the compact on densification and microstructure development. Compacts were made by dry-pressing. During the initial stage of sintering, the fibrous particles rearranged and bundles of particles were formed. The volume of pores between bundles of particles decreased on further heating. Grain growth started when the sintered density reached ca. 56% of the theoretical density. Higher temperatures of sintering increased the degree of the crystal axis orientation. Thus, highly orientated sintered bodies with high densities were prepared by heating at 1500 °C. 相似文献
10.