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排序方式: 共有162条查询结果,搜索用时 15 毫秒
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Shuntaro Suzuki Tsuneo Suzuki Hisayuki Suematsu Weihua Jiang Kiyoshi Yatsui 《Thin solid films》2004,457(1):139-142
Titanium iron oxide (Ti-Fe-O) thin films have been successfully deposited by pulsed laser deposition (PLD). Experiments were carried out by using some targets. One was a Ti-50 at.% Fe-sintered target, while the others were Ti and Fe plates with various surface area ratio [SR=SFe/(SFe+STi)] from 30 to 70%. The thin films were analyzed by X-ray diffractometry, Rutherford backscattering spectroscopy (RBS) and transmission electron microscopy (TEM). From XRD analysis, the main phase in the thin films deposited at SR=30 and 50% was β-Ti (Fe). By increasing SR to 70%, the main phase of the thin film changed to TiFe. By phase diagram, composition of TiFe must be between Ti-47.5-50.3 at.% Fe at a temperature of 1085 °C. However, the composition of the thin film deposited at SR=70% was found to be Ti0.15Fe0.62O0.23. Thus, the composition of Fe in the thin film was much greater than the solubility limit. This fact suggests two possibilities. One is that the thin films, which we have deposited, were in a metastable state. The other is that metal oxides of amorphous state could be contained in the thin film. 相似文献
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Recently,small hydroelectric generators have gained attention as a further development in water turbine technology for ultra low head drops in open channels.The authors have evaluated the application of cross-flow water turbines in open channels as an undershot type after removing the casings and guide vanes to substantially simplify these water turbines.However,because undershot cross-flow water turbines are designed on the basis of cross-flow water turbine runners used in typical pipelines,it remains unclear whether the number of blades has an effect on the performance or flow fields.Thus,in this research,experiments and numerical analyses are employed to study the performance and flow fields of undershot cross-flow water turbines with varying number of blades.The findings show that the turbine output and torque are lower,the fluctuation is significantly higher,and the turbine efficiency is higher for runners with 8 blades as opposed to those with 24 blades. 相似文献
4.
Polypropylene plasticization and photodegradation with a TiO2/poly(ethylene oxide)/methyl linoleate paint photocatalyst system 下载免费PDF全文
The photodegradation of polypropylene (PP) film was performed by a TiO2/polyethylene oxide (PEO)/plant oil paint photocatalyst system. The photodegradation underwent two stages of development as follows: Initially PP reacted with linoleic acid radical originated from the photoreaction of plant oil component. Second, the linoleic acid graft‐polymer was decomposed, and then PP chain scission was caused. The process was studied using methyl linoleate (ML) in detail. The melting point of the 24 h‐photodegraded PP slightly decreased, and those of the 48 h‐ and 96 h‐ones drastically did as compared with the pristine PP. The crystallinity (χc) decreased at the 48 h photodegradation time and drastically increased at the 96 h one. The 24 h‐photodegraded PP showed the 77% Young's modulus, 88% tensile strength, and 103% strain at break values to those of the pristine PP. The ML graft‐polymerization and decomposition brought about the PP plasticizing and chemi‐crystallization, causing the PP degradation. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39909. 相似文献
5.
Koichiro Ishibashi Hisayuki Higuchi Toshinobu Shimbo Kunio Uchiyama Kenji Shiozawa Naotaka Hashimoto Shuji Ikeda 《Analog Integrated Circuits and Signal Processing》1999,20(2):85-94
There are various kinds of analog CMOS circuits in microprocessors. IOs, clock distribution circuits including PLL, memories are the main analog circuits. The circuit techniques to achieve low power dissipation combined with high performance in newest prototype chip in the Super H RISC engines are described. A TLB delay can be decreased by using a CAM with a differential amplifier to generate the match signal. The accelerator circuit also helps to speed up the TLB circuit, enabling single-cycle operation. A fabricated 96-mm2 test chip with the super H architecture using 0.35-m four metal CMOS technology is capable of 167-MHz operation at 300 Dhrystone MIPS with 2.0-W power dissipation. 相似文献
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The thermally enhanced photoinduced reorientation behavior of random and diblock copolymer films of methyl methacrylate and methacrylate with a photo-cross-linkable 4-(4-methoxycinnamoyloxy)biphenyl (MCB) side groups was investigated by irradiating with linearly polarized ultraviolet light and subsequently annealing. Random copolymers were synthesized by free radical copolymerization, while diblock ones were obtained by an atom transfer radical polymerization method with a PMMA macroinitiator. The photoinduced optical anisotropy was thermally amplified when the copolymer exhibited a liquid crystalline phase. The random copolymers with a high composition of MCB side groups reverted the orientation direction and inhibited molecular aggregation. For the diblock copolymers, the reorientation behavior was analogous to the methacrylate homopolymer with MCB side groups and transmission electron microscopy revealed a phase separation structure with molecular orientation of the MCB groups. 相似文献
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Jun Shirahata Tetsutaro OhoriHiroki Asami Tsuneo SuzukiTadachika Nakayama Hisayuki SuematsuYoshiharu Nakajima Koichi Niihara 《Thin solid films》2011,519(11):3497-3500
Chromium oxynitride thin films were deposited by radio-frequency (RF) reactive unbalanced magnetron sputtering at various O2 flow rates onto Si(100) and glassy carbon substrates. The compositions of the thin films were analyzed by Rutherford backscattering spectroscopy. The thin films were found to contain up to 44 at.% oxygen. In Fourier-transform infrared spectra, a peak attributed to the Cr-N bond of CrN was observed, but no peak attributable to the Cr-O bond of Cr2O3 was found. The textures of the thin films were observed by transmission electron microscopy, which revealed that samples had a columnar structure. The hardness of the thin films was measured by nanoindentation. The hardness increased from 20 GPa to a maximum value of 31 GPa with increasing oxygen content. 相似文献
10.
Kuibao Zhang Zhengyi Fu Tadachika Nakayama Tsuneo Suzuki Hisayuki Suematsu Koichi Niihara 《Materials Research Bulletin》2011,46(11):2155-2162
Based on the preparation of ordered mesoporous Al2O3 powder using P123/isopropoxide aluminum/HNO3 reaction system, hierarchically macro/mesoporous alumina monoliths were successfully fabricated by introducing PEG8000 as the phase-segregation initiator to generate macropores. The effects of PEG8000 and P123 contents on the monolithic and hierarchical morphology were investigated systematically. With appropriate selection of the starting composition, monolithic skeletons with bimodal macropores interconnected by mesostructured walls can be synthesized in both the dried gels and calcined samples. The well-defined macropores are in close-celled structure dispersed in large-sized mesoporous matrix. The mesopore size can be regulated by adjusting the PEG8000 content while its shape is governed by P123 content. The well-developed alumina monolith, MMA-P20, exhibits high surface area of 287 m2/g and narrowly distributed mesopores with median size of 13 nm after calcinaton. 相似文献