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排序方式: 共有314条查询结果,搜索用时 359 毫秒
1.
Synthesis of hydrous SnO2 and SnO2-coated TiO2 powders by the homogeneous precipitation method and their characterization 总被引:1,自引:0,他引:1
Hydrous SnO2 and SnO2-coated TiO2 powders were synthesized by the homogeneous precipitation method using urea and the products were characterized by X-ray diffraction, thermogravimetry, differential thermal analysis, scanning electron microscopy and energy- dispersive X-ray microanalysis. Electrical conductivities were measured with an impedance analyser. Hydrous SnO2 powder prepared under conditions without SO
4
2–
ions was a bulky product containing 75 wt% of water. The addition of SO
4
2–
ions to the solution changed bulky hydrous SnO2 to a dense product; approximately spherical particles were obtained with an average particle size of 0.14 ± 0.03 m. with 13.5 wt % of absorbed water. Antimony-doped hydrous SnO2 prepared under conditions with SO
4
2–
ions consisted of approximately spherical particles with an average particle size of 0.17 ± 0.04 m with 15.0 wt % of absorbed water. Hydrous SnO2-coated TiO2 powders with a good dispersion state and with various Sn/Ti ratios were prepared under conditions with SO
4
2–
ions. All the as-prepared coated powders were white, but the products doped with Sb3+ ions were turned to pale blue by heat treatment at 600° C for 1 h and their electrical conductivities increased by orders of about 3.0 in comparison with those of the other two. 相似文献
2.
Hui-suk Yun Haoshen Zhou Itaru Honma 《Journal of Inorganic and Organometallic Polymers and Materials》2006,16(2):169-173
Self-standing transparent submillimeter-thick (∼0.34 mm) mesoporous titania films were prepared using the evaporation-induced
self-assembly (EISA) of a triblock copolymer template and titanium tetraethoxide. Performing EISA at low temperature and low
humidity improved the transparency and continuity of the films. As synthesized films had a well-defined hexagonal mesostructure
and the existence of both amorphous titania and anatase nanocrystallites (2 nm) was confirmed. The films that were calcined
at 400°C were composed of anatase nanocrystallites (14–16 nm) and had a BET surface area of 90 m2 g−1 with 13-nm pores. The films were characterized using XRD, FE-SEM, TEM, and N2 adsorption–desorption measurements.
An erratum to this article can be found at 相似文献
3.
Miyahara Daiki Ueda Itaru Hayashi Yu-ichi Mizuki Takaaki Sone Hideaki 《International Journal of Information Security》2021,20(5):729-740
International Journal of Information Security - Card-based cryptography is an attractive and unconventional computation model; it provides secure computing methods using a deck of physical cards.... 相似文献
4.
Ian A. Brummel Daniel E. Drury Andrew R. Kitahara Farid El Gabaly Jon F. Ihlefeld 《Journal of the American Ceramic Society》2021,104(2):711-721
Lithium zirconium phosphate (LiZr2P3O12) thin films have been prepared on platinized silicon substrates via a chemical solution deposition approach with processing temperatures between 700°C and 775°C. Films that were subject to a single high-temperature anneal were found to crystallize at temperatures above 725°C. Crystallization was observed in films annealed after each deposited layer at 700°C and above. In both cases, grain size was found to increase with annealing temperature. Ion conductivity was found to increase with annealing temperature in singly annealed films. In per-layer annealed films ion conductivity was found to initially increase then decrease with increasing annealing temperature. A maximum ion conductivity of 1.6 × 10−6 S/cm was observed for the singly annealed 775°C condition, while a maximum ion conductivity of 5.8 × 10−7 S/cm was observed for the 725°C per-layer annealed condition. These results are consistent with an increasing influence of cross-plane, internal interface resistance and vapor phase carrier loss in the per-layer annealed samples. This work demonstrates that post-deposition processing methods can strongly affect the ion conducting properties of LiZr2P3O12 thin films. 相似文献
5.
Quenching stress arises within a thermally sprayed splat as its thermal contraction after solidification is constrained by
the underlying solid. Dependence of the quenching stress in plasma-sprayed deposits of Ni-20Cr alloy and alumina on the substrate
temperature during spraying was discussed in conjunction with the change in the nature of the interlamellar contact between
splats. It was found by mercury intrusion porosimetry and observation of cross sections of impregnated deposits that the interlamellar
contact is improved significantly by raising the substrate temperature during deposition from 200 to 600 °C. The positive
dependence of the quenching stress on the substrate temperature in this temperature range was attributed to a stronger constraint
against thermal contraction of sprayed splats after solidification due to the improved contact. 相似文献
6.
7.
Fujihara H. Goto M. Kitahara T. Okuno H. G. 《IEEE transactions on audio, speech, and language processing》2010,18(3):638-648
8.
Particle-free silicon and nickel thin films were successfully fabricated by laser-ablating a melted section of their target surface, which gives a high evaporation pressure at the melting point. The influence of direct evaporation from a melted target was reduced negligibly by melting the target only locally with a focused electron beam (e-beam) and increasing the laser frequency. The silicon films fabricated by the present method, pulse laser deposition of a partially molten target, were able to firmly adhere to the substrates and withstood steel needle scratching, unlike e-beam-evaporated films. 相似文献
9.
Fujiyoshi T. Shiratake S. Nomura S. Nishikawa T. Kitasho Y. Arakida H. Okuda Y. Tsuboi Y. Hamada M. Hara H. Fujita T. Hatori F. Shimazawa T. Yahagi K. Takeda H. Murakata M. Minami F. Kawabe N. Kitahara T. Seta K. Takahashi M. Oowaki Y. Furuyama T. 《Solid-State Circuits, IEEE Journal of》2006,41(1):54-62
A single-chip H.264 and MPEG-4 audio-visual LSI for mobile applications including terrestrial digital broadcasting system (ISDB-T / DVB-H) with a module-wise, dynamic voltage/frequency scaling architecture is presented for the first time. This LSI can keep operating even during the voltage/frequency transition, so there is no performance overhead. It is realized through a dynamic deskewing system and an on-chip voltage regulator with slew rate control. By the combination with traditional low power techniques such as embedded DRAM and clock gating, it consumes only 63 mW in decoding QVGA H.264 video at 15 frames/sec and MPEG-4 AAC LC audio simultaneously. 相似文献
10.
Yoshihiro Sagisaka Itaru Ishibashi Tamotsu Nakamura Masahiro Sekizawa Yuh Sumioka Masahiro Kawano 《Journal of Materials Processing Technology》2012,212(9):1869-1874
The authors proposed double-layer-type environmentally friendly lubricants, which were composed of an undercoat, superior in adhering to a material, and an overcoat, superior in reducing the friction between the material and the die. The performance of these lubricants for cold forging was evaluated by the ring compression test, the combined forward rod-backward can extrusion-type friction test and the combined forward conical can-backward straight can extrusion-type friction test. The double-layer-type lubricants showed comparable friction characteristics and anti-pick-up properties to a conversion coating lubricant, when the film thickness and surface treatment before coating were improved. In a practical application by cold multistage forging, the double-layer-type lubricants showed a similar performance to a conversion coating lubricant. 相似文献