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991.
Kenji Takahashi Katsutoshi Fujii Sadashi Sawamura Charles D. Jonah 《Radiation Physics and Chemistry》1999,55(5-6):579-581
The Stokes shifts of coumarin 153 (C153) in CF3H, CO2 and C2H6 have been measured at several reduced densities (0.3–1.8). For C153 in CF3H, the shifts increase with a decrease in reduced density and show a maximum value at a reduced density of 0.5. In non-polar solvents, the shifts are not dramatically altered as a function of reduced density but slightly increase with a decrease in the reduced density. 相似文献
992.
The reactions of N-(5,6-dihydro[1]benzothiepino[5,4-d]pyrimidin-4-yl)amidines or its amide oxime derivatives with hydroxylamine hydrochloride under basic condition gave abnormal cyclization products via a ring cleavage of pyrimidine component accompanied with a ring closure of [1,2,4]oxadiazole. 相似文献
993.
It is found numerically that the time-bandwidth product (TBP) of optical pulse from a gain-switched semiconductor laser operating under a sufficient gain saturation condition increases monotonously with increasing modulation amplitude. This enhancement of the TBP becomes remarkable for longer-wavelength semiconductor lasers (1.3, 1.55 μm) having large value of the gain compression factor ε (∼ 10−23 m3), making the pulse chirp estimation using the TBP difficult. 相似文献
994.
995.
996.
Hidetaka Tobita Narito Tani Takeshi Sakai 《Journal of Polymer Science.Polymer Physics》2000,38(18):2342-2350
The heterochain crosslinking theory is applied to postgel behavior in the free‐radical crosslinking copolymerization of vinyl and divinyl monomers. In this context, the crosslinked polymer formation can be viewed as a system in which the primary chains formed at different times are combined in accordance with the statistical chain‐connection rule governed by the chemical reaction kinetics. Because the primary chains are formed consecutively, the number of chain types N must be extrapolated to infinity, N → ∞. Practically, such extrapolation can be conducted with the calculated values for only three different N values. The analytical expressions for the weight fraction and average molecular weights of the sol fraction are derived for the general primary chain length distribution function in free‐radical polymerization. Illustrative calculations show that the obtained results agree with those from the Monte Carlo method, and that the postgel properties in free‐radical crosslinking copolymerization systems could be significantly different from those in randomly crosslinked systems. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 2342–2350, 2000 相似文献
997.
Takushi Kurihara Tsutomu Tani Sigeru Maeyama Yasuhiko Sakamoto 《Journal of heterocyclic chemistry》1980,17(5):945-951
The reaction of ethyl 3-ethoymethylene-2,4-dioxovalerate (EMDV) ( 1 ) with 2-aminobenzamide ( 2 ), 2-aminobenzthioamide ( 3 ), 2-aminobenzmethylamide ( 4 ) and 3-amino-2-methyl- or phenylpyrazole-4-carbox-amides ( 6 and 7 ) produced ethyl 3-aminomethylene-2,4-dioxovalerates ( 10, 15, 16, 18 and 19 ), which led to pyrrolo[1,2-a]quinazoline-1,5-diones ( 11, 22 and 23 ) and pyrrolo[1,2-a]pyrazolo[4,3-e]pyrimidine-1,5-diones ( 24 and 25 ) under the acidic condition, respectively. Analogously, 2-aminothiophenol reacted with 1 to give 21 , which was subsequently derived to pyrrolo[1,2-a]benzothiazolin-l-one ( 26 ) under the neutral condition. Furthermore, we prepared the heterocyclic steroidal molecules ( 41, 43, 45, 47, 49 and 51 ) by condensation of 11 and 26 with hydrazine, methylhydrazine and phenylhydrazine. 相似文献
998.
Kawashima Natsumi Kitazaki Tomoya Nogo Kosuke Nishiyama Akira Wada Kenji Ishimaru Ichiro 《Optical Review》2020,27(6):530-541
Optical Review - We propose a superimposing interferogram method to enhance the sensitivity and interference definition of spatial-phase-shift interferometers. The proposed method uses a multi-slit... 相似文献
999.
Tomohiro Yasuda Yi Li Kenji Miyatake Michiko Hirai Masato Nanasawa Masahiro Watanabe 《Journal of polymer science. Part A, Polymer chemistry》2006,44(13):3995-4005
A series of novel polyimide electrolytes having long pendant sulfo‐ or phosphoalkoxy groups were synthesized for fuel‐cell applications. Sulfodecyloxy‐, phosphodecyloxy‐, and sulfophenoxydodecyloxy‐substituted benzidine monomers were synthesized from dihydroxybenzidine. These monomers were copolymerized with naphthalene tetracarboxylic dianhydride and fluorenylidene dianiline to give the corresponding polyimides. A flexible, ductile, and self‐standing membrane was obtained via casting from the polyimide solution. Because the acid groups were on long pendant side chains and away from the main chains, the polyimide membrane showed improved oxidative and hydrolytic stability in comparison with the polyimides with sulfonic acid groups on the main chains or on the short side chains. High thermal stability (no glass‐transition temperature and a decomposition temperature > 200 °C) was also obtained. The polyimide membrane displayed high proton conductivity of 10?1 S cm?1 at 120 °C. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3995–4005, 2006 相似文献
1000.
Nobutoshi Kiba Ayumi Koga Masaki Tachibana Kazue Tani Hitoshi Koizumi Tetsuo Koyama Akira Yamamura Kunio Matsumoto Tohru Okuda Koki Yokotsuka 《Analytical sciences》2006,22(1):95-98
A chemiluminometric flow injection analytical system for the quantitation of L-histidine is described. Histidine oxidase (EC 1.4.3.-) from Brevibacillus borstelensis KAIT-B-022 was immobilized on tresylated poly(vinyl alcohol) beads and packed into a stainless-steel column. The hydrogen peroxide produced was detected chemiluminometrically by a flowthrough sensor containing immobilized peroxidase (EC 1.1 1.1.7). The maximum sample throughput was 10 h(-1). The calibration graph was linear from 0.05 to 5 mM; the detection limit (signal to noise ratio = 3) was 0.01 mM. The activity of immobilized histidine oxidase reduced to 65% of the initial value after 350 injections. The system was applied to the determination of L-histidine in fish meat, such as salmon, tunny, bonito, and mackerel. 相似文献