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排序方式: 共有311条查询结果,搜索用时 156 毫秒
121.
Takahiro Souma Hideo Furuhashi Toshio Yoshikawa Akinori Maeda Yoshiyuki Uchida Kenzo Kojima Asao Ohashi Shizuyasu Ochiai Teruyoshi Mizutani 《Electrical Engineering in Japan》2002,140(2):36-43
Vanadyl phthalocyanine (VOPc) crystal thin films were prepared on poly(ethylene terephthalate) (PET) film. The VOPc film prepared on PET substrate at 120 °C had Phase II. The third harmonic (TH) intensity of the VOPc film was measured by the marker fringe method. The third optical susceptibility (χ(3)) estimated from TH intensity is 3.5 × 10?9 esu. The transition from Phase I to Phase II of the VOPc film was enhanced with corona charging. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 140(2): 36–43, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10022 相似文献
122.
The copolymerization of divinyl adipate (DVA) with isobutyl vinyl ether (IBVE) was conducted at 70 and 80 °C in benzene using azobisisobutyronitrile (AIBN), at a concentration as high as 0.50 mol l?1 as the initiator, where the concentrations of DVA and IBVE were 0.40 and 0.60 mol l?1, respectively. The copolymerization proceeded homogeneously, without any gelation, to yield soluble copolymers in spite of the high molar ratio of DVA as an excellent cross‐linker for IBVE. The copolymer yield increased with time, and the number‐average molecular weight (Mn = 0.9–2.4 × 104 g mol?1) from gel permeation chromatography (GPC) and molecular weight distribution (Mw/Mn = 1.5–7.6) of the resulting copolymer increased with copolymer yield. The cyanopropyl group, as a fragment of AIBN, was incorporated as a main constituent in the copolymer, the fraction of which increased from ca 10 to ca 20 % with copolymer yield, hence indicating that the copolymerization is an initiator–fragment incorporation radical polymerization. The copolymers also contained IBVE units (10–30 %) and DVA units with intact double bond (8–36 %) and without double bond (45 %). The intrinsic viscosity of the copolymer was very low (0.1 dl g?1) at 30 °C in tetrahydrofuran. The results from GPC–multi‐angle laser light scattering (MALLS), transmission electron microscopy (TEM) and MALLS revealed that individual copolymer molecules were formed as hyperbranched nanoparticles. Copyright © 2004 Society of Chemical Industry 相似文献
123.
Hiroaki Munakata Yukiko Ebisawa Yuka Takashima Michael C. Wrinn Andrew C. Scheiner John M. Newsam 《Catalysis Today》1995,23(4):403-408
First principles, density functional theory embodied in the DMol program has been applied to agostic ethyl-Ti-complexes, including the dmpe complex, [Ti(-CH2CH3)C13(dmpe)], where DMPE=(Me2PCH2)2 and its model complex, [Ti(−CH2CH3)Cl3(PH3)2]. The ethyl moiety of the complexes can adopt two limiting conformations, staggered and eclipsed. In the model complex, [Ti(−CH2CH3)C13(PH3)2], both conformers are found to form agostic structures upon geometry optimization subject to Cs symmetry constraint, with the agostic eclipsed structure being the lower in energy. Full geometry optimization of the dmpe complex, [Ti(−CH2CH3)C13(dmpe)], yields an agostic structure with geometrical features similar to those measured by single crystal X-ray analysis. It is shown that the HOMO orbital contributes substantially to the agostic bonding. 相似文献
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125.
Taylor Renee R.; Jason Leonard A.; Shiraishi Yukiko; Schoeny Michael E.; Keller Jessica 《Canadian Metallurgical Quarterly》2006,51(2):157
Objective: To evaluate the impact of a consumer-driven rehabilitation program on perceptions of loss and gain of interpersonal relationships, energy, material objects, work benefits and opportunities, well-being, and experiences of mastery in persons with chronic fatigue syndrome. Study Design: Participants were randomly assigned to a program group (n = 23) or a control group (n = 24). Outcomes were assessed (a) at baseline, (b) after program participants completed an illness management group, and (c) after they completed one-on-one peer counseling. Setting: A community-based advocacy organization for individuals with disabilities. Interventions: Four months of illness management groups followed by 7 months of one-on-one peer counseling emphasizing goal setting and goal attainment. Main Outcome Measure: The Conservation of Resources Evaluation scale. Results: Significant gains were observed for program participants across all categories of resource gain--interpersonal, energy, material, work, well-being, and mastery resources. Effect sizes were moderate to large. Conclusions: Programs in which participatory action research methods are used may have a positive impact on resource acquisition for individuals with chronic fatigue syndrome. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
126.
Evaluation of characteristic deuterium distributions of ephedrines and methamphetamines by NMR spectroscopy for drug profiling 总被引:1,自引:0,他引:1
Matsumoto T Urano Y Makino Y Kikura-Hanajiri R Kawahara N Goda Y Nagano T 《Analytical chemistry》2008,80(4):1176-1181
We have established a method for quantitative analysis of the deuterium contents (D/H) at the phenyl, methine, benzyl, N-methyl and methyl groups of l-ephedrine/HCl, d-pseudoephedrine/HCl and methamphetamine/HCl by 2H NMR spectroscopy. Comparison of the 5 position-specific D/H values of l-ephedrine/HCl and d-pseudoephedrine/HCl prepared by three methods (chemical synthesis, semichemical synthesis, and biosynthesis) showed that chemically synthesized ephedrines and semisynthetic ephedrines have highly specific distributions of deuterium at the methine position and at the benzyl position, compared with the other positions. The classification of several methamphetamine samples seized in Japan in terms of the D/H values at these two positions clearly showed that the methamphetamine samples had been synthesized from ephedrines extracted from Ephedra plants or semisynthetic ephedrines but not from synthetic ephedrine. This isotope ratio analysis method should be useful to trace the origins of seized methamphetamine in Southeast Asia. 相似文献
127.
Kento Fujiura Mitsuru Naito Yukiko Tanaka Masaru Tanaka Yurie Nakanishi Hirotaka Ejima Lumi Negishi Tomoya Kujirai Hitoshi Kurumizaka Seiichi Ohta Kanjiro Miyata 《应用聚合物科学杂志》2024,141(11):e55044
Poly(ethylene glycol) (PEG) modification, also known as PEGylation, has been extensively used to improve the stability of nanoparticles for nanomedical applications. However, PEG exhibits antigenicity in some formulations, motivating researchers to explore alternative polymers. Herein, poly(vinyl ether) (PVE) derivatives are highlighted as promising alternatives to PEG because they form intermediate water molecules that suppress non-specific protein adsorption and platelet adhesion to the material surface. We prepared a water-soluble PVE derivative, poly(2-methoxyethyl vinyl ether) (PMOVE), and utilized it as a surface modifier for gold nanoparticles (AuNPs) as model nanoparticles. PMOVE with a thiol terminus was synthesized and confirmed to form an intermediate water molecule using differential scanning calorimetry. Similar to the synthesis of PEGylated AuNPs (PEG-AuNPs), PMOVE-modified AuNPs (PMOVE-AuNPs) were successfully fabricated with an appreciably high density of PMOVE palisades via a thiol-gold coordination reaction. Similar to PEG-AuNPs, PMOVE-AuNPs showed reduced serum protein adsorption and prolonged blood circulation. Additionally, no significant cytotoxicity was observed after incubation of a murine macrophage cell line, RAW264.7, with PMOVE-AuNPs. Our results indicate that the PMOVE modification increases the stealthiness of nanoparticles that is equivalent to that achieved by PEGylation. 相似文献
128.
Gold nanorods were fixed on an ITO plate and used for the spectroscopic sensing and Surface-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (SALDI-MS) of oligopeptides (angiotensin I). The longitudinal surface plasmon bands of the gold nanorods responded to the 10(-10) M angiotensin solution that was cast on the ITO plate. The SALDI-MS measurements had an ultra-high sensitivity to the angiotensin on the ITO plate. A very small surface density (5 × 10(-19) mol cm(-2)) of angiotensin could be detected at m/z = 1297 with a good signal/noise ratio (S/N = 11). The ITO plate, which was modified with gold nanorods, was found to be effective in collecting angiotensin molecules adjacent to the gold nanorods, and the SALDI processes that were induced by the photoabsorption of the gold nanorods efficiently contributed to the desorption and ionization of the angiotensin. 相似文献
129.
130.
Yasuo Morimoto Hiroto Izumi Yukiko Yoshiura Taisuke Tomonaga Takako Oyabu Toshihiko Myojo Kazuaki Kawai Kazuhiro Yatera Manabu Shimada Masaru Kubo Kazuhiro Yamamoto Shinichi Kitajima Etsushi Kuroda Kenji Kawaguchi Takeshi Sasaki 《International journal of molecular sciences》2016,17(8)
We conducted inhalation and intratracheal instillation studies of zinc oxide (ZnO) nanoparticles in order to examine their pulmonary toxicity. F344 rats were received intratracheal instillation at 0.2 or 1 mg of ZnO nanoparticles with a primary diameter of 35 nm that were well-dispersed in distilled water. Cell analysis and chemokines in bronchoalveolar lavage fluid (BALF) were analyzed at three days, one week, one month, three months, and six months after the instillation. As the inhalation study, rats were exposed to a concentration of inhaled ZnO nanoparticles (2 and 10 mg/m3) for four weeks (6 h/day, 5 days/week). The same endpoints as in the intratracheal instillation study were analyzed at three days, one month, and three months after the end of the exposure. In the intratracheal instillation study, both the 0.2 and the 1.0 mg ZnO groups had a transient increase in the total cell and neutrophil count in the BALF and in the expression of cytokine-induced neutrophil chemoattractant (CINC)-1, CINC-2, chemokine for neutrophil, and heme oxygenase-1 (HO-1), an oxidative stress marker, in the BALF. In the inhalation study, transient increases in total cell and neutrophil count, CINC-1,-2 and HO-1 in the BALF were observed in the high concentration groups. Neither of the studies of ZnO nanoparticles showed persistent inflammation in the rat lung, suggesting that well-dispersed ZnO nanoparticles have low toxicity. 相似文献