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排序方式: 共有2395条查询结果,搜索用时 290 毫秒
1.
Kazuaki Katagiri Shinya Honda Sayaka Minami Daiki Kimu Shimpei Yamaguchi Takuya Ehiro 《先进材料力学与结构力学》2020,27(18):1541-1550
Abstract The I-shaped cross-sectional beam of CFRP (CFRP I-beam) is usually manufactured by the continuous protrusion method. Carbon fibers can only be arranged in the longitudinal direction. The CFRP I-beam with arbitrary arrangement of carbon fiber was manufactured with applying the electro-activated deposition molding method. The carbon fiber fabric was immersed in the deposition solution and energized, epoxy resin precipitated around carbon fiber and impregnated. The resin-impregnated fabric was installed to the mold, and the CFRP I-beam was fabricated. The CFRP I-beam was subjected to three-point bending tests, and the relationship between load-deflection was simulated by finite-element analysis. 相似文献
2.
Seung Han Ryu Seil Kim Young-Tae Kwon Young Ki Park Sung-Oong Kang Hong-Baek Cho Yong-Ho Choa 《应用聚合物科学杂志》2020,137(8):48390
Here, we report a facile approach to electrostatically couple the surface charges of graphite nanoplate (GNP) fillers and poly(methyl methacrylate) (PMMA) polymer particles using ethylene maleic anhydride (EMA) copolymer as an electrostatic coupling agent. Our strategy involved switching the intrinsic repulsive electrostatic interactions between the directly exfoliated GNPs fillers and the PMMA particles to attractive electrostatic surface interactions for preparing core(PMMA)-shell (GNP) precursor in order to optimizing 3-dimensionally dispersed polymer nanocomposite. As a result, the electrical conductivity of the composites dramatically increased by a factor of 16.7 in the EMA-coupled GNP/PMMA composites compared with that of the EMA-free GNP/PMMA composites. In addition, the percolation threshold was also notably reduced from 0.32 to 0.159 vol% after electrostatic coupling of the GNPs fillers and PMMA particles. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48390. 相似文献
3.
H. Sakata A. Katagiri M. Yokoi T. Kato H. Morimoto 《Journal of Low Temperature Physics》2003,131(3-4):275-279
We have measured the tunneling spectra in Bi2Sr2CaCu2O8 with a scanning tunneling microscope(STM) at various tip-sample distances by changing the tunneling conductance in a controlled manner. When the tunneling conductance is increased from 1×10–9 to 1×10–5 S, the spectra do not show changes in particular. However, the gap value decreases steeply and the asymmetric back ground density of states turns inverted V-shaped one above 6×10–4 S. The changes in the tunneling spectra at the high tunneling conductances are explained by the enhancement of the local carrier density induced by the pressure that the STM tip applied to the sample. 相似文献
4.
This paper presents a low‐cost RF parameter estimation technique using a new RF built‐in self‐test (BIST) circuit and efficient DC measurement for 4.5 to 5.5 GHz low noise amplifiers (LNAs). The BIST circuit measures gain, noise figure, input impedance, and input return loss for an LNA. The BIST circuit is designed using 0.18 μm SiGe technology. The test technique utilizes input impedance matching and output DC voltage measurements. The technique is simple and inexpensive. 相似文献
5.
Woo Gon Kim Sung Ho Kim Woo Seog Ryu 《Journal of Mechanical Science and Technology》2002,16(11):1420-1427
The Monkman-Grant (M-G) and its modified parameters were evaluated for type 316LN and modified 9Cr-Mo stainless steels prepared
with minor element variations. Several sets of creep data for the two alloy systems were obtained by constant-load creep tests
in 550-650°C temperature range. The M-G parameters,m, m’,C, andC’ were proposed and discussed for the two alloy systems. Them value of the M-G relation was 0.90 in type 316LN steel and 0.84 in modified 9Cr-Mo steel. Them’, value of the modified relation was 0.94 in type 316LN steel and 0.89 in 9Cr-Mo steel. Although creep fracture modes and
creep properties between type 316LN and modified 9Cr-Mo steels showed a basic difference, the M-G and its modified relations
demonstrated linearity quite well. Them’ of modified relation almost overlapped regardless of the creep testing conditions and chemical variations in the two alloy
systems, and the parameterm’ was closer to unity than that of the M-G relation. 相似文献
6.
7.
J.H. Kaneko T. Tanaka S. Kawamura Y. Oshiki K. Tsuji M. Katagiri K. Ochiai T. Nishitani F. Fujita A. Homma T. Sawamura T. Iida M. Furusaka 《Diamond and Related Materials》2005,14(11-12):2027
Radiation detector was made of a high-quality CVD polycrystalline diamond composed of frost column like structure diamond grains, and induced charge distribution spectra and drift velocities were measured by using alpha particles. As a result, the CVD polycrystalline achieved maximum induced charge of 83% of HP/HT type IIa diamond. Moreover, the CVD crystal had lower charge loss on electrons compared with the HP/HT type IIa diamond. Drift velocities of electrons and holes were ve = 7.7 × 104 and vh = 7.3 × 104cm/s at an electric field of 20 kV/cm, respectively. In addition, response function measurement for 14 MeV neutrons was carried out. 相似文献
8.
To investigate the molecular basis of altered expression of the H-cadherin gene, we used polymerase chain reaction-single strand conformation polymorphism and DNA sequencing to examine the H-cadherin gene in 48 primary breast cancers in which loss of the long arm of chromosome 16 had been detected. We identified no mutations other than somatic 5-bp deletion within the coding region in a single tumor. The very low frequency of mutation found in these experiments suggests that H-cadherin is usually not a primary target for carcinogenesis in human breast cancers, and that reduction of its expression is likely to be a consequence of some other genetic event(s). 相似文献
9.
We propose a new design method, called discriminative feature extraction for practical modular pattern recognizers. A key concept of discriminative feature extraction is the design of an overall recognizer in a manner consistent with recognition error minimization. The utility of the method is demonstrated in a Japanese vowel recognition task 相似文献
10.
High-temperature and controlled humidity treatment before drying has proven to be highly effective in preventing surface checks by forming drying sets in the surface layer of boxed-heart square timber in Japan. In this study, we examined the differences of the surface drying sets on sugi timber under different treatment temperatures. As a result, the width of a surface check after drying was much smaller at a treatment temperature of 120°C than at 80°C, and this indicates that the drying set with 120°C treatment would be larger than that with 80°C treatment. Also we observed that treatment temperature had a greater effect on the drying set as the drying advanced. 相似文献