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71.
72.
众所周知,微生物,如藻类、细菌、霉菌(真菌和酵母)以及病毒可在物品的表面寄生和存活,尤其是当死角、粗糙的表面或微缝中有残存的营养物质时,微生物…在聚合物表面的生长可导致褪色、污渍、臭味、生物膜、交叉感染并最终降低机械强度,降低产品使用寿命。汽巴可为解决上述的问 相似文献
73.
Youichi Ogo Kenji Nomura Hiromichi Ohta Masahiro Hirano Hideo Hosono 《Thin solid films》2006,496(1):64-69
A reactive solid-phase epitaxy (R-SPE) method combines deposition of a thick amorphous or polycrystalline layer with a desired chemical composition and post-deposition solid-phase epitaxial growth. The solid-phase epitaxial growth is invoked by thermal annealing with an assistance of a sacrificial layer working as an epitaxial template. Thereby it enables us to grow high-quality epitaxial films of complex oxides whose epitaxial films are not grown by conventional high-temperature growth techniques. It was reported that 2-nm-thick ZnO layers worked as template for growing InGaO3(ZnO)m (m = integer) epitaxial films. The present study extended the R-SPE technique to growth of various complex oxides with chemical compositions of RAO3(MO)m and to use of various epitaxial template layers. We found that mono oxide epitaxial layers such as In2O3 and Ga2O3 work as template layers as well. Alternatively, a ZnO epitaxial layer is also applicable to ZnO-free compounds. The films obtained were grown heteroepitaxially on YSZ(111) and single-crystalline when the fabrication conditions are optimized. 相似文献
74.
Inflow boiling, gravity effects on the distribution of both phases are observed in a heated tube and heat transfer coefficients due to two-phase forced convection is deteriorated in microgravity. In narrow channels between heated and unheated plates, the increase in subcooling enlarges a size of flattened bubble and reduces the frequency of detachment under microgravity conditions resulting the emphasis of heat transfer deterioration. To clarify reasons for the unknown behaviors of interfacial distribution and corresponding characteristics in heat transfer not easily be clarified through the experiments on ground, the opportunity on the experiments utilizing long-term microgravity duration realized in ISS is required. The experiments on microgravity boiling and two-phase flow are proposed by the collaboration of researchers in five countries. A common test loop is designed to conduct multiple experiments by the interchangeable structures of test sections; a transparent heated tube for the visualized flow boiling, a stainless tube for the measurement of CHF data, a copper surface for the heat transfer data of nucleate boiling with superimposed liquid flows in a duct, a glass heated plate with multiple array of small temperature sensors and transparent heaters for the clarification of mechanisms in nucleate boiling heat transfer, and one or two models of cold plates for practical applications. A direction of researches in the present discipline is proposed based on the existing experimental results and on the idea developed by the present authors. 相似文献
75.
Yukio Tachibana Shigeaki Nakagawa Takeshi Takeda Akio Saikusa Takayuki Furusawa Kuniyoshi Takamatsu Kazuhiro Sawa Tatsuo Iyoku 《Nuclear Engineering and Design》2003,224(2):1010-197
Safety demonstration tests using the High Temperature Engineering Test Reactor (HTTR) will be conducted for the purpose of demonstrating inherent safety features of High Temperature Gas-cooled Reactors (HTGRs) as well as providing the core and plant transient data for validation of HTGR safety analysis codes. The first phase safety demonstration test items include the reactivity insertion test and the coolant flow reduction test. In the reactivity insertion test, which is the control rod withdrawal test, one pair out of 16 pairs of control rods is withdrawn, simulating a reactivity insertion event. The coolant flow reduction test consists of the partial loss of coolant flow test and the gas circulators trip test. In the partial loss of coolant flow test, primary coolant flow rate is slightly reduced by control system. In the gas circulators trip test one and two out of three gas circulators are run down, simulating coolant flow reduction events. The gas circulators trip tests, in which position of control rods are kept unchanged, are simulation tests of anticipated transients without scram (ATWS). 相似文献
76.
A. Yoshikawa C. Fujiwara H. Sato T. Nishi H. Ohta T. Fukuda Y. Waseda G. Boulon M. Ito Y. Guyot K. Lebbou 《Optical Materials》2004,26(4):385
Ca8(La,Yb)2(PO4)6O2 (Yb:CLPA) single crystals with the apatite-type structure could be grown from the melt using the Czochralski method. Grown crystal was 18 mm in diameter and 110 mm in length. It is transparent with slightly blue color. Neither visible inclusion nor crack was observed. Thermal conductivity of Yb:CLPA was calculated from the values of thermal diffusivity, heat capacity measurement and density. Luminescent characterization was carried out from the results of emission, absorption and Raman spectrum. 相似文献
77.
KenjiYoshii AkioNakamura MasaichiroMizumaki NaoshiIkeda Jun'ichiroMizuki 《中国稀土学报(英文版)》2004,22(6):733-738
Magnetic properties were investigated for the rare-earth 3d-transition metal oxides with the perovskite structure. Intriguing magnetic phenomena were reviewed for a few systems:magnetization peak effect in the titanates, magnetization reversal in the chromites and metallic ferromagnetism in the cobahites. The results suggest an important role of the rare-earth ions for the magnetic properties of such complex oxides. 相似文献
78.
Akira Masutani Tony Roberts Bettina Schüller Akio Yasuda Akira Sakaigawa Graham Cross David Bloor 《Journal of the Society for Information Display》2004,12(3):301-307
Abstract— A novel preparation method for dichroic dye‐doped polymer‐dispersed liquid crystals has been developed. This was achieved by creating a porous polymer matrix first by washing out the liquid crystal from a polymer‐dispersed liquid crystal (PDLC), which is then refilled with dye‐doped liquid crystal. Optimizing the liquid crystal used in the refilling results in decreased turn‐on voltage and faster response time. Poster‐standard reflectivity and newspaper‐standard contrast was demonstrated with a 3.8‐in. QVGA reflective TFT display with a drive voltage of 10 V. 相似文献
79.
Ohta Y Yano H Suzuki R Yoshida M Kawashima N Nakazawa K 《Proceedings of the Institution of Mechanical Engineers. Part H, Journal of engineering in medicine》2007,221(6):629-639
A number of orthoses have been developed to restore stance and walking in paraplegic subjects. Compliance, however, has been limited, mainly owing to walking effort. Use of the forces produced by actuators is an effective way to solve the problem of the considerable effort required for orthotic gait, namely high muscular effort and high energy expenditure. The purpose of the present study was to investigate the effects of assistance by external actuators on the orthotic gait of spinal cord injury (SCI) patients. Two kinds of linear actuator were developed by using direct current (d.c.) motors for assisting the knee and hip joint of a gait orthosis. They were mounted on the knee and hip joint of a commercial advanced reciprocating gait orthosis (ARGO), and a new two-degree-of-freedom externally powered gait orthosis was thus developed. The orthosis was assessed through inter-subject experiments on five male adult complete SCI patients. Owing to the short training period available for the assisted gait, simultaneous operation of both joint actuators was not conducted: either the knee actuation or the hip actuation was executed only. Thus, the knee actuator and the hip actuator were assessed with a T12 subject and with subjects for T5, T8, T11, and T12 respectively. The motions of the gaits, assisted by the linear actuators, were measured by a Vicon 370 system, and the general gait parameters and compensatory motions were evaluated. Results demonstrated that (a) all subjects could walk without falling, assisted either by the knee or the hip actuator; (b) both the knee and hip joint actuator increased the gait speed and the step length; (c) the knee flexion produced by the orthosis improved the dynamic cosmesis of walking; and (d) lateral compensatory motions as well as vertical ones tended to decrease when the hip joint was assisted, which could contribute to a reduction in walking effort. 相似文献
80.