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21.
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
22.
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
23.
在氮气保护下,利用预辐照接枝技术在高密度聚乙烯(HDPE)膜上接枝苯乙烯三甲基氯化铵(VBTAC)单体,以甲基丙烯酸二甲氨基乙酯(DMAEMA)单体作为接枝辅助单体来提高VBTAC的接枝率,制备出阴离子交换膜,解决了在HDPE上难以直接接枝聚合VBTAC的问题.本文研究了接枝条件及接枝液的组分对接枝的影响,并用X射线显微分析方法研究了VBTAC的接枝进程和接枝分布. 相似文献
24.
Kosuke Oiwa Rikito Okamoto Shizuka Bando Akio Nozawa 《Artificial Life and Robotics》2018,23(2):218-224
The amount of mental work using information equipment has been increasing because of a rapid growth of an information society. Accumulation of short-term mental work can cause various stresses and a disturbance of circadian rhythm and lead to fatigue, anxiety, and distraction. Estimation and understanding the physiopsychological states is desired for decreasing or controlling stresses to maintain health. There have been several investigations on the assessment of short-term physiopsychological states using infrared thermography. However, the method has been used rarely for assessing long-term physiopsychological states. In the present study, extraction of independent components related to long-term physiological signals is attempted by applying independent component analysis to facial thermal images obtained over 6 months (July–December). Furthermore, multiple regression analysis is attempted to create psychological model by facial thermal images. As the result, extracted independent components are shown to represent the strong features in nasal, mouth, cheek, eyebrow, and forehead regions. Attempting multiple regression analysis, features in nasal and mouth regions contributed to depression or dejection mood, features in cheek, eyebrow and forehead regions contributed to fatigue and features in tip of nasal, eyebrow and mouth regions contributed to state anxiety. 相似文献
25.
A nano-mechanical model has been developed to calculate the tensile modulus and the tensile strength of randomly oriented short carbon nanotubes (CNTs) reinforced nanocomposites, considering the statistical variations of diameter and length of the CNTs. According to this model, the entire composite is divided into several composite segments which contain CNTs of almost the same diameter and length. The tensile modulus and tensile strength of the composite are then calculated by the weighted sum of the corresponding modulus and strength of each composite segment. The existing micro-mechanical approach for modeling the short fiber composites is modified to account for the structure of the CNTs, to calculate the modulus and the strength of each segmented CNT reinforced composites. Multi-walled CNTs with and without inter-tube bridging have been considered. Statistical variations of the diameter and length of the CNTs are modeled by a normal distribution. Simulation results show that CNTs inter-tube bridging, length and diameter affect the nanocomposites modulus and strength. Simulation results have been compared with the available experimental results and the comparison concludes that the developed model can be effectively used to predict tensile modulus and tensile strength of CNTs reinforced composites. 相似文献
26.
Tsutomu Furuzono Koji Seki Akio Kishida Taka-Aki Ohshige Kazunori Waki Ikuro Maruyama Mitsuru Akashi 《应用聚合物科学杂志》1996,59(7):1059-1065
Disiloxane–aromatic polyamide(aramid) multiblock copolymers(2SiPASs) were synthesized using 1,3-bis(3-aminopropyl)-1,1,3,3-tetramethyldisiloxane(BATS) as an analog of aramidsilicone resin consisting of aromatic polyamide and poly(dimethylsiloxane) (PDMS). 2SiPASs afford a transparent and toughened plastic film. The surface properties of 2SiPAS were investigated by X-ray photoelectron spectroscopy (xps) and static contact angle measurement. The results of surface analysis suggested that BATS content of the 2SiPAS surface increased with increasing BATS content in bulk. The interaction between the platelets and the 2SiPAS surface was found to be very weak when the BATS content reached 26 wt % in bulk. © 1996 John Wiley & Sons, Inc. 相似文献
27.
Makoto Tanaka Mikio Taguchi Tsuysohi Takahama Toru Sawada Shigeru Kuroda Takao Matsuyama Shinya Tsuda Akio Takeoka Shoichi Nakano Hiroshi Hanafusa Yukinori Kuwano 《Progress in Photovoltaics: Research and Applications》1993,1(2):85-92
A new solar cell structure named HIT (Heterojunction with Intrinsic Thin layer) has been developed based on new artificially constructed junction (ACJ) technology. In this structure a non-doped a-Si thin layer was inserted between the p(a-Si)/n(c-Si) heterojunction, improving the output characteristics and achieving a conversion efficiency of 18.1%. This structure was applied to cast polycrystalline silicon solar cells of a practical size. A high conversion efficeincy of 13.6% was obtained with a cell size of 10 cm × 10 cm using various technologies, including hydrogen plasma passivation. 相似文献
28.
Masato Nishikuni Tsuyoshi Takahama Shingo Okamoto Kunimoto Ninomiya Hidenori Nishiwaki Shinya Tsuda Akio Takeoka Michotoshi Ohnishi Shoichi Nakano Yukinori Kuwano 《Progress in Photovoltaics: Research and Applications》1994,2(3):211-219
A new approach to high-performance a-Si solar cells was studied. a-Si films prepared at a high substrate temperature (> 250°C) have a higher absorption coefficient and a low Si H2 bond density. the effect of deposition temperature on the open-circuit voltage (Voc) has been investigated systematically for glass/SnO2 Ipin/metal and glass/metal/nip/indium tin oxide (ITO) structure a-Si solar cells. The Voc is found to depend strongly on the thermal history of the p/i interface. A short-circuit current of 19.5 mA/cm−−2 was achieved for an a-Si solar cell using an a-Si i-layer with a thickness of 4000 Å, which was prepared at a substrate temperature of 270°C. 相似文献
29.
Nongluk Sriwilaijaroen Akio Kadowaki Yuriko Onishi Nobuki Gato Makoto Ujike Takato Odagiri Masato Tashiro Yasuo Suzuki 《Food chemistry》2011
Fruit-juice concentrate of Japanese apricot (Prunus mume Sieb. et Zucc.) has been shown to be effective against influenza A infection in MDCK cells. In this study, we isolated five components from the fruit-juice concentrate of Japanese apricot, 5-(hydroxymethyl)-2-formylfuran (HMF), 1-[5-(2-formylfuryl)methyl]dihydrogen 2-hydroxypropane-1,2,3-tricarboxylate (mumefural, MF), 2-[5-(2-formylfuryl)methyl]dihydrogen 2-hydroxypropane-1,2,3-tricarboxylate (MF‘), 1-[5-(2-formylfuryl)methyl]hydrogen 1-hydroxyethane-1,2-dicarboxylate (MA1) and 2-[5-(2-formylfuryl)methyl]hydrogen 1-hydroxyethane-1,2-dicarboxylate (MA2), and investigated their inhibitory activities against the novel influenza A/Narita/1/2009 (H1N1) pandemic virus hemagglutinin and neuraminidase functions, which are essential for viral attachment and budding, respectively. An hemagglutination inhibition assay indicated that MF and MF‘ were effective at minimum hemagglutination concentrations of 3.1 and 6.3 mM, respectively. An inhibition study for sialidase activity of the neuraminidase spike showed that MF was the most active anti-sialidase compound with an IC50 value of 0.21 ± 0.01 mM, followed by MA2 (IC50, 0.71 ± 0.09 mM), MA1 (IC50, 1.64 ± 0.31 mM) and MF‘(IC50, 1.62 ± 0.22 mM). Furthermore, MF was shown to inhibit the growth of the pandemic virus in a dose-dependent manner (62 ± 3% inhibition at 5 mM). The results suggest that MF, a citric acid ester linked to HMF at the 1-position of the propane backbone, might be a lead compound for the development of anti-influenza A inhibitors. 相似文献
30.
Several methods to determine number-average molecular weight Mn and weight-average molecular weight Mw, of a polymer sample are proposed from diffusion and sedimentation velocity measurements at the θ point. According to these methods, Mn and Mw are determined from the diffusion constant vs. molecular weight relationship, and also from the equations of Svedberg and Flory–Mandelkern, using the 2nd-order and the –2nd-order diffusion constants. These methods have been applied to four samples of polydisperse polystyrene in the θ solvent, cyclohexane at 35°C. It was experimentally ascertained that Mn and Mw of each sample determined by the present methods were in good agreement with the results of column fractionation, light scattering, and calculated values from molecular weight distribution curve within experimental errors. It is concluded that the present methods are useful for determining Mn and Mw, since the reliabilities of Mn and Mw values, which are fundamental quantities of polymer characterization, can be raised by comparing the experimental data observed by conventional methods such as osmotic pressure, light scattering, and the Archibald method with those observed by the present methods. 相似文献