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11.
The setup and deposition conditions of electrode arrangement and pressure have been studied to synthesize diamond films at high growth rate on wide area efficiently by arc discharge plasma jet chemical vapor deposition. An apparatus has been used in which four plasma torches, one is used for cathode and the others for divided anodes, are arranged and the positions of these torches are changeable. Growth rate, deposition area and thickness of diamond films have increased with changing the electrode arrangements without improvement of thickness variation. Maximum growth rate of our apparatus has occurred at the pressure of 6.7 kPa and diamond films that have less variations of quality and surface roughness have been synthesized at lower pressure during deposition. Moreover, a high conversion rate, which is the ratio of carbon atoms that form diamond in supplied methane gas, of 16% has been obtained at the pressure of 6.7 kPa and methane concentration of 2%. 相似文献
12.
T. Kawakami Y. Koide N. Teraguchi Y. Tomomura A. Suzuki Masanori Murakami 《Journal of Electronic Materials》1998,27(8):929-935
In order to prepare low resistance ohmic contacts to p-ZnSn by the “deposition and annealing (DA)” technique which has been
extensively used for GaAs and Si-based devices, formation of a heavily doped layer by the p-ZnSe/metal reaction is required.
For p-ZnSe/Ni contacts, Ni and Se reacted preferentially at the ZnSe/Ni interface upon annealing at temperatures higher than
250°C. However, capacitance-voltage measurements showed that the net acceptor concentration (NA-ND) close to the p-ZnSe/Ni interface was reduced upon the Ni/ZnSe reaction, resulting in high contact resistance. For p-ZnSe/Au
contacts, neither Au/ZnSe reaction nor reduction of the acceptor concentration were observed after annealing at temperatures
lower than 300°C. This indicates that although the metal/p-ZnSe reaction is mandatory to prepare a heavily doped layer, the
reaction induced an increase in the compensation donors in the p-ZnSe substrate. In order to increase the acceptor concentration
in the vicinity of the p-ZnSe/metal interface through diffusion from the contact materials, Li or O which was reported to
play the role of an acceptor in ZnSe was deposited with a contact metal and annealed at elevated temperatures. Ni or Ag was
selected as the contact metal, because these metals were expected to enhance Li or O doping by reacting with ZnSe. However,
the current density-voltage characteristics of the Li(N)/Ni and Ag(O) contacts exhibited rectifying behavior, and the contact
resistances increased with increasing annealing temperature. The present results indicated that, even though the acceptor
concentration in the p-ZnSe substrate increased by diffusion of the dopants from the contact elements, an increment of the
compensation donors was larger than that of the acceptors. The present experiments indicated that preparation of low resistance
ohmic contacts by forming a heavily doped intermediate layer between p-ZnSe and metal is extremely difficult by the DA technique. 相似文献
13.
Nobuo Ishizawa Atsushi Saiki Takeshi Yagi Nobuyasu Mizutani Masanori Kato 《Journal of the American Ceramic Society》1986,69(2):18-C-
Crystals of yttria partially stabilized zirconia were grown by the arc-image floating-zone technique and studied by transmission electron microscopy. Crystals annealed at 1700°C consist of tetragonal precipitates and a cubic matrix. The platelike domains in a precipitate are twin-related tetragonal variants stacked alternately parallel to the (011) twin plane. The axial relations between the tetragonal precipitate and the cubic matrix are [100]tetragonal |[100]cubic , [011]tetragonal |[011]cubic . 相似文献
14.
H Asamoto M Kawahara F Iwami M Kuba K Furuse T Tamura N Saijo M Shimoyama 《Canadian Metallurgical Quarterly》1998,28(12):745-748
BACKGROUND: Etoposide is a highly schedule-dependent drug. We investigated combination chemotherapy of oral etoposide and intravenous cisplatin for small cell lung cancer (SCLC). METHODS: Fifty-seven patients with SCLC with extensive disease (ED) or limited disease (LD) with pleural effusion registered in the 21 institutions of the Japan Clinical Oncology Group were treated with oral etoposide 40 mg/m2/d for 21 days and cisplatin 80 mg/m2 on day 1 of every 28-period day. The entry period was between February 1992 and August 1995. The actual percentages of patients treated with etoposide were 93.6, 89.5, 92.3 and 96.9% in the first, second, third and fourth cycles, respectively. RESULTS: Nine patients (15.8%) achieved a complete response resulting in an overall response rate of 82.5% (95% confidence interval, 70.1-91.3%). Leukopenia and thrombocytopenia of grade 3 or 4 were observed in 36 (49.1%) and 8 (14.0%) patients, respectively. Anemia of grade 3 or 4 occurred in 28 (49.1%) patients. Nausea, vomiting, anorexia and alopecia were common adverse events. One patient died of hemoptysis due to grade 4 thrombocytopenia. The mean survival time was 47.0 weeks. CONCLUSIONS: This dose and schedule of administration of etoposide in combination with cisplatin are considered to be clinically active. However, prolonged gastrointestinal toxicity of oral etoposide was a problem in comparison with the standard etoposide platinum regimen given by intravenous administration. 相似文献
15.
16.
Preparation of spherical fine ZnO particles by the spray pyrolysis method using ultrasonic atomization techniques 总被引:1,自引:0,他引:1
Tian-Quan Liu Osamu Sakurai Nobuyasu Mizutani Masanori Kato 《Journal of Materials Science》1986,21(10):3698-3702
An ultrasonic atomizer was used in the spray pyrolysis method to prepare fine, spherical and uniform ZnO particles. Almost spherical particles were obtained successfully which had a mean particle size of 0.15 m and had a very narrow particle size distribution. By using alcohol as the solvent, it was found that the particles do not have hollow shell layers which could usually be observed in the spray pyrolysis process by using water as the solvent. The morphology of the ZnO particles was strongly affected by the concentration of the starting solution. 相似文献
17.
Takashi Ogihara Tadashi Ikemoto Nobuyasu Mizutani Masanori Kato Yukuaki Mitarai 《Journal of Materials Science》1986,21(8):2771-2774
The Ta2O5 powders synthesized by the hydrolysis of tantalum pentaethoxide, Ta(OC2H5)5 in alcoholic solution were monodispersed fine oxide particles, which were a uniform, spherical shape, non-agglomerate, and had a narrow size distribution. They grew to 1.2m after ageing for 1 h after hydrolysis. Powder X-ray diffraction and differential thermal analysisthermogravimetric analysis showed the particles were amorphous and hydrated. These particles lost the water at 290° C and gave well-crystalline Ta2O at 740° C. Throughout these thermal processes, the particle morphology was kept almost the same. 相似文献
18.
Takeshi Yagi Kazuo Shinozaki Nobuo Ishizawa Nobuyasu Mizutani Masanori Kato Akihiko Tsuge 《Journal of the American Ceramic Society》1988,71(7):334-C
The thermal diffusivity of AlN ceramics was significantly decreased by the addition of SiO2 . The AlN ceramics with 4 wt% SiO2 could not be densified by pressureless sintering in the temperature range 1400° to 1800°C. The thermal diffusivity of these samples was very low because of their porous structure. The AlN ceramics containing 2, 4, and 8 wt% SiO2 were densified by hot-pressing and also had low thermal diffusivity. In these samples, the grains of the 27R polytype that resulted from the reaction between AlN and SiO2 were dispersed, obstructing the conduction of heat. The relation between the amount of 27R polytype and the thermal diffusivity of the AlN ceramics was determined. 相似文献
19.
Hisao Ichijo Tetsuro Suehiro Aizo Yamauchi Shigeo Ogawa Masanori Sakurai Nobuo Fujii 《应用聚合物科学杂志》1982,27(5):1665-1674
A poly(vinyl alcohol) (PVA) fiber support incorporating various aminoacetal functional groups has been developed for immobilizing enzymes. The aminated PVA fiber seems to adsorb enzymes with electrostatic force of attraction; thus the immobilization procedure is simple. By the use of this fiber having immobilized enzymes, the reaction between enzymes and substrates is nearly independent of the size of subtstrates. This newly developed type of fiber, which is formed by a mass superfine fibers (SFF), each measuring 1 μm or less in diameter, permits much more increased surface area than the conventional enzyme immobilization supports. Our studies of the properties of the fiber for immobilization of enzymes show the following results: (1) SFF has a greater ability for the immobilization of invertase than ordinary fibers; (2) dimethyl-aminated SFF has the best performance for the immobilization of invertase. From these results, it is concluded that the dimethyl-aminated SFF is an excellent support for the immobilization of invertase. 相似文献
20.
Uniaxially oriented thin films of poly(ethylene terephthalate) (PET), poly(ethylene 2,6-naphthalene dicarboxylate) (PEN) and their blends were prepared by applying shear strain to their respective melts, and the resulting morphologies were studied by transmission electron microscopy. Selected-area electron diffraction of each film revealed well-defined uniaxial orientation of polymer chains in the shearing direction. In the uniaxially oriented thin film of PEN, stacked-lamellar structure with the average long period of 27 nm consisting of a crystalline region about 15 nm thick and an amorphous one about 12 nm thick was found here and there in the dark-field image: PEN-type. On the other hand, stacked-lamellar structure was rarely observed in the case of PET: PET-type. In PET/PEN blends, the morphologies changed from the PET-type to the PEN-type with increasing content of PEN. 相似文献