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931.
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933.
Takeshi Mori Yasuhisa Fukuda Hirokazu Okamura Keiji Minagawa Seizo Masuda Masami Tanaka 《Journal of polymer science. Part A, Polymer chemistry》2004,42(11):2651-2658
New thermosensitive polymers were synthesized by copolymerization between N‐vinylacetamide (NVA) and methyl acrylate whose homopolymers are soluble and insoluble in water, respectively. The lower critical solution temperature (LCST) of the obtained copolymers ranged between 59 and 83 °C, and the LCST increased with an increasing NVA content in the copolymers. The effectiveness of various salts addition on lowering the LCST of the copolymer solutions followed Hoffmeister series. NaCl and Na2SO4 addition linearly lowered the LCST with an increasing salts concentration, and slopes of the lines were almost constant regardless of the copolymer composition. The effectiveness of alcohols with various alkyl chain lengths on lowering the LCST did not follow the viscosity B coefficient values of the alcohols, which was probably the result of preferential adsorption of the alcohols to the copolymer. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2651–2658, 2004 相似文献
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936.
The ESR of Si:P and (Si:P):Sb systems made by ion implantation has been observed. An anomalous line-broadening appears in the (Si:P):Sb system, and is considered to be due to the large spin-orbit interaction of Sb donor impurity. The effective spin-lattice relaxation time, T1eff, of both the systems is found to be dominated by a thin layer with the shortest relaxation time T1(χ). 相似文献
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938.
Heishun Zen Toshiteru Kii Kai Masuda Hideaki Ohgaki Tetsuo Yamazaki 《Infrared Physics & Technology》2008,51(5):382-385
A mid-infrared free electron laser (FEL) has been constructed for energy science in the Institute of Advanced Energy, Kyoto University. The FEL system consists of a compact S-band Linac and an undulator to generate 4–13 μm coherent mid-infrared radiations. The Linac consists of a 4.5 cell rf gun with a thermionic cathode and a 3-m traveling-wave-type accelerator tube fed by 10 MW and 20 MW rf power, respectively. We have succeeded to produce 40 MeV, 40 mA and 3 μs electron beams. Last December, the 9.2 μm spontaneous emission from the undulator generated by 29.5 MeV electron beams was observed for the first time. Further optimization parameters of both the electron beam and the optical cavity are being pursued for an FEL lasing in the near future. 相似文献
939.
Takadate A Masuda T Murata C Shibuya M Isobe A 《Chemical & pharmaceutical bulletin》2000,48(2):256-260
Structural features of fluorescent methoxycoumarins were examined from the viewpoint of substituent effect and ring structure in connection with intramolecular charge-transfer (ICT). The fluorescence of methoxycoumarins depended primarily upon the ICT from a C6-electron-donating group to the substituents at the C3-position of the coumarin ring. Furthermore, the presence of a lactone ring itself, including a carbonyl group, cyclic ether oxygen and ethylenic bond as partial ring structures, was found to be essential for fluorescing in methoxycoumarins according to the fluorescent behaviors of chemically deformed model compounds. 相似文献
940.
An experiment on a Ramsey resonance for pulsed neutrons is discussed. The separated oscillatory fields for nuclear magnetic resonance were synchronized with a neutron pulse, and then the Ramsey resonance was observed as a function of the neutron velocity. The neutron spin was manipulated as a function of the neutron velocity. The phase of one of the oscillatory fields was modulated as a function of the neutron time of flight for a neutron velocity measurement. 相似文献