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41.
The existence states of deuterium in LiAlO2 were analyzed by in situ IR absorption spectroscopy during irradiation with 3 keV at room temperature. Multiple IR absorption peaks that were related to O-D stretching vibrations were observed, mainly at 2650 cm−1 (O-Dα), 2600 cm−1 (O-Dβ), and 2500 cm−1 (O-Dγ). The O-Dα was assigned to the surface O-D. The O-Dβ and O-Dγ were interpreted as two distinct O-D states for three candidates: O-D of substitutional D+ for Li+; O-D of substitutional D+ for Al3+; and O-D of interstitial D+. O-Dβ was the dominant O-D state for deuterium irradiated into LiAlO2, and had higher stability than O-Dγ. Heating after ion irradiation led to the desorption of D2 and an increase in the intensity of O-Dβ, which implies that some of the deuterium irradiated into LiAlO2 exists in non-O-D states, such as D− captured by F centers. 相似文献
42.
东丽以Innovation by Chemistry为核心,通过融合有机化学、高分子科学、生物化学、纳米技术等进行技术革新,挑战具有创新意义的新素材及新技术,为全球用户创造新的价值,致力于改善地球环境,技术创新开发。东丽纤维研究所(中国)有限公司成立于2002年5月,与日本东丽株式会社共同致力于中国的纤维及高分子材料的研究。设有南通总公司和上海分公司,本次就公司的研究开发概要作报告。着重报告东丽(株)正在推进的环境友好型新材料研究开发状况。包括生物基聚合物聚乳酸、PTT、生物尼龙等相关的技术概要及特征。另外介绍一下具有环境保护技术的绿色工艺的纤维素纤维。 相似文献
43.
Biosynthesis of Trehangelin in Polymorphospora rubra K07–0510: Identification of Metabolic Pathway to Angelyl‐CoA 下载免费PDF全文
Dr. Yuki Inahashi Taro Shiraishi Dr. Kaia Palm Prof. Dr. Yoko Takahashi Prof. Dr. Satoshi Ōmura Prof. Dr. Tomohisa Kuzuyama Dr. Takuji Nakashima 《Chembiochem : a European journal of chemical biology》2016,17(15):1442-1447
Trehangelins are trehalose angelates discovered from endophytic actinomycete Polymorphospora rubra K07‐0510. We identified the trehangelin biosynthetic gene cluster, including genes that encode a glycoside hydrolase‐like protein (thgC), α‐amylase (thgD), 3‐ketoacyl‐ACP synthase III (thgI), 3‐ketoacyl‐ACP reductase (thgK), enoyl‐CoA hydratase (thgH) and acyl transferase (thgJ). Heterologous expression of thgH, thgI, thgJ and thgK confirmed the importance of these genes in the biosynthesis of trehangelin A. Enzymatic activity studies showed that ThgI catalyses the condensation of acetyl‐CoA and methylmalonyl‐CoA to 2‐methylacetoacetyl‐CoA (MAA‐CoA), ThgK catalyses NADPH‐dependent reduction of MAA‐CoA to 3‐hydroxy‐2‐methylbutyryl‐CoA (HMB‐CoA) and ThgH catalyses the dehydration of HMB‐CoA to angelyl‐CoA (AN‐CoA). This is the first report on the elucidation of the enzymatic formation of AN‐CoA. 相似文献
44.
Hirotoshi Miyazaki Kazutoshi Terada Toshiaki Sato Hitoshi Maruyama Takuji Okaya 《应用聚合物科学杂志》1996,60(12):2149-2157
In dispersion polymerization of styrene in ethanol, effects of a reactive steric stabilizer, poly(vinyl acetate/vinyl alcohol) copolymer with a thiol end group (P(VAc/VA)-SH), were investigated. In the absence of the thiol end group, the dispersion coagulated at the middle stage of the polymerization, while in the presence of the thiol end group, the polymerization proceeded successfully to result in close to monodisperse particles. The reactive thiol group acts as a site of formation of the block copolymer, that is, polystyrene-b-P(VAc/VA), which is utilized as an effective dispersant. From the measurement on molecular weights during the course of polymerization, two polymerization loci were realized. Addition of butyl methacrylate to styrene affected markedly not only rate of polymerization but also particle size. © 1996 John Wiley & Sons, Inc. 相似文献
45.
Mitsuhide Maeda Takuji Keno Yuji Suzuki Toshiro Abe 《Electrical Engineering in Japan》1996,116(3):107-115
A static induction (SI) thyristor using a normally-off planar-gate structure in a low power class has been developed to be used as a power switching device in a three-phase inverter circuit. A 600 V-15 A class SI thyristor with very fast switching time (tgt, tgq) and low forward voltage drop (VTM) was designed and created. This design was performed with a reasonable wafer structure (n?/n/p+), an n? base carrier concentration and thickness, and a gate structure (gate diffusion length and gate-gate pitch). Microscopic processing was used to obtain this SI thyristor. The performance trade-off between turn-off time and forward voltage drop is controlled by a lifetime control process using proton irradiation that results in a very fast switching time with tgt of 500 ns and tgq of 500 ns with VTM of 1.5 V (at IT= 18 A). At a current level of IT = 18 A, the current density in the active area becomes 200 A/cm2, which indicates that the performance of the SI thyristor is superior to that of conventional IGBTs and MOSFETs. 相似文献
46.
Takuji Kobori Shuichi Kamagata 《Computer-Aided Civil and Infrastructure Engineering》1992,7(4):265-281
Abstract: Dynamic Intelligent Buildings (DIB) are the active seismic response controlled structures which replace the ordinary seismic structural elements with active controllers (AC). In this system the computer acts as the control unit for the AC. For the feasibility study of the DIB the authors develop a DIB analytical simulator and define the DIB response spectra, the AC performance spectra, and the DIB performance response surface from the analytical results. The DIB response properties of an active adustable stiffness system (A2S2) and an active counter force system (ACFS) are illustrated. 相似文献
47.
Sorption and permeation of CO2 in poly(ethylene terephthalate) crystallized by sorption of high-pressure CO2 were examined below 1 atm at temperatures from 15 to 65°C. A large solubility and a high permeability of CO2 in this specimen were observed compared to poly(ethylene terephthalate) crystallized by thermal annealing to a similar degree. A large unrelaxed volume is expected to be left in the specimen after removal of high-pressure CO2 compared to the data of other PET samples. The thermal history during the measurements up to 65°C, which causes relaxation of the specimen, was shown to decrease CO2 solubility. On the other hand, permeation data after annealing show not only decreased permeability but also increased apparent diffusivity. The results mean a lower mobility of gases sorbed in the unrelaxed volume than that of ordinarily dissolved gases, which corresponds to the partial immobilization model. 相似文献
48.
Highly Efficient 2D/3D Hybrid Perovskite Solar Cells via Low‐Pressure Vapor‐Assisted Solution Process 下载免费PDF全文
Ming‐Hsien Li Hung‐Hsiang Yeh Yu‐Hsien Chiang U‐Ser Jeng Chun‐Jen Su Hung‐Wei Shiu Yao‐Jane Hsu Nobuhiro Kosugi Takuji Ohigashi Yu‐An Chen Po‐Shen Shen Peter Chen Tzung‐Fang Guo 《Advanced materials (Deerfield Beach, Fla.)》2018,30(30)
The fabrication of multidimensional organometallic halide perovskite via a low‐pressure vapor‐assisted solution process is demonstrated for the first time. Phenyl ethyl‐ammonium iodide (PEAI)‐doped lead iodide (PbI2) is first spin‐coated onto the substrate and subsequently reacts with methyl‐ammonium iodide (MAI) vapor in a low‐pressure heating oven. The doping ratio of PEAI in MAI‐vapor‐treated perovskite has significant impact on the crystalline structure, surface morphology, grain size, UV–vis absorption and photoluminescence spectra, and the resultant device performance. Multiple photoluminescence spectra are observed in the perovskite film starting with high PEAI/PbI2 ratio, which suggests the coexistence of low‐dimensional perovskite (PEA2MAn?1PbnI3n+1) with various values of n after vapor reaction. The dimensionality of the as‐fabricated perovskite film reveals an evolution from 2D, hybrid 2D/3D to 3D structure when the doping level of PEAI/PbI2 ratio varies from 2 to 0. Scanning electron microscopy images and Kelvin probe force microscopy mapping show that the PEAI‐containing perovskite grain is presumably formed around the MAPbI3 perovskite grain to benefit MAPbI3 grain growth. The device employing perovskite with PEAI/PbI2 = 0.05 achieves a champion power conversion efficiency of 19.10% with an open‐circuit voltage of 1.08 V, a current density of 21.91 mA cm?2, and a remarkable fill factor of 80.36%. 相似文献
49.
50.
Takuji Murata Hiroshi Tamai Takao Morinobu Mitsuhiro Manago Akira Takenaka Hiroyuki Takenaka Makoto Mino 《Lipids》1992,27(11):840-843
The β-carotene concentrations in plasma, blood cells and buccal mucosal cells were determined by high-performance liquid chromatography
with electrochemical detection. This method was 1,000 times more sensitive than the conventional spectrophotometric method.
Polymorphonuclear cells and red blood cells had lower β-carotene levels than the other cells. After oral administration of
580 mg/day of all-trans β-carotene to human male volunteers for a week, the β-carotene concentrations in all cell types increased at least several
times above the original levels. 相似文献