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排序方式: 共有198条查询结果,搜索用时 156 毫秒
21.
M Balázs H Feussner G Hirzinger K Omote A Ungeheuer 《Canadian Metallurgical Quarterly》1998,17(3):45-48
A model of the activity of a treatment and prophylactic institution under conditions of marketing economy is proposed. This model helps realize the method of a total-systems approach to assessing the quality of medical care. 相似文献
22.
A ceramics acid, calcined at temperatures above 1000 °C, was obtained by impregnating aluminum hydroxide with aqueous ammonium
metatungstate followed by calcining in air at 1000–1200 °C (1–5 wt% W); its acidity and catalytic activity for decompositions
of toluene, ethylbenzene, and cumene are higher than those of silica-alumina. 相似文献
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25.
Yumiko Kaji Ryoji Mitsuhashi Xuesong Lee Hideki Okamoto Takashi Kambe Naoshi Ikeda Akihiko Fujiwara Minoru Yamaji Kenji Omote Yoshihiro Kubozono 《Organic Electronics》2009,10(3):432-436
C60 and picene thin film field-effect transistors (FETs) in bottom contact structure have been fabricated with poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS) electrodes for a realization of mechanical flexible organic FETs. The C60 thin film FETs showed n-channel enhancement-type characteristics with the field-effect mobility μ value of 0.41 cm2 V?1 s?1, while the picene thin film FET showed p-channel enhancement-type characteristics with the μ of 0.61 cm2 V?1 s?1. The μ values recorded for C60 and picene thin film FETs are comparable to those for C60 and picene thin film FETs with Au electrodes. 相似文献
26.
Kazushi Shibutani Jun Nakai Ketkanok Aphichartsuphapkhajorn Yoshihito Kayaki Shigeki Kuwata Yoshihiko Arao Masatoshi Kubouchi 《应用聚合物科学杂志》2021,138(17):50311
The effect of oxygen and additional oxygen providers on furfuryl alcohol polymerization was investigated through chemical analyses and mechanical evaluation. NMR, UV–vis, Fourier transform infrared, and gas chromatography–mass spectrometry (GC–MS) results suggested that atmospheric oxygen and the further addition of an oxygen source functioned as an activator for the entire network polymerization. Interestingly, the construction of a conjugated structure on the furan linear chain, which is key to three-dimensional cross-linking, also appears to be accelerated in the presence of oxygen. Furthermore, the introduction of oxygen providers into the curing system successfully enhanced the mechanical properties of the cured furan resin. 相似文献
27.
Highly acidic catalysts stronger than the SO4/ZrO2 superacid with an acid strength of Ho –16.04 were obtained by kneading Zr(OH)4 with ammonium sulfate together with chlorides of Ir, Pt, Rh, Ru, Os, and Pd followed by calcining in air at 600°C, the metal concentration being equivalent to Pt of 7.5 wt% based on the hydroxide. The catalysts with Ir and Pt materials were highest in activity for the skeletal isomerization of butane to isobutane. The present catalysts were not obtained by treating the crystallized oxide, ZrO2 calcined at 700°C, but the amorphous form followed by calcination to the crystallization.Superacids by metal oxides, VI. For previous publication in this series see ref. [1]. 相似文献
28.
Qingshan Zhu Kazuhisa Shobu Eiji Tani Kazushi Kishi Seiki Umebayashi 《Journal of the American Ceramic Society》1999,82(8):2276-2278
Molybdenum carbosilicide composites (SiC-Mo≤5 Si3 C≤1 ) were fabricated via the melt-infiltration process. The fracture behavior of the composites was studied from room temperature up to 1800°C in 1 atm (∼105 Pa) of argon. The bend strength of the composites slightly increased at ∼1200°C, because of the brittle-ductile transition of the intermetallic phase. The composites retained ∼90% of their room-temperature strength, even at 1700°C. Compressive creep tests were performed over a temperature range of 1760°-1850°C and a stress range of 200–250 MPa. The creep rate of the SiC-Mo≤5 Si3 C≤1 composites was approximately an order of magnitude higher than that of reaction-bonded SiC. 相似文献
29.
Ultramultiple roundtrips of surface acoustic wave on sphere realizing innovation of gas sensors 总被引:1,自引:0,他引:1
Yamanaka K Ishikawa S Nakaso N Takeda N Sim DY Mihara T Mizukami A Satoh I Akao S Tsukahara Y 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2006,53(4):793-801
A thin beam of wave usually diverges due to diffraction, which is a limitation of any device using such waves. However, a surface acoustic wave (SAW) on a sphere with an appropriate aperture does not diverge but is naturally collimated, realizing ultramultiple roundtrips along an equator of the sphere. This effect is caused by the balance between diffraction and focusing on a spherical surface, and it enables realization of high-performance ball SAW sensors. The advantage of ball SAW is most fully appreciated when applied to a very thin sensitive film for which the multiple-roundtrip enhances the sensitivity, but the attenuation loss is not very large. It is exemplified in a hydrogen gas sensor that realizes a wide sensing range of 10 ppm to 100% for the first time, and realizes relatively fast response time of 20 s without heating the sensitive film. 相似文献
30.