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151.
152.
Tomomi Nagasawa Bungo Ochiai Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2006,44(19):5519-5524
Infrared thermography was employed to analyze multiple batches of the thermally latent polymerization of 3‐ethyl‐3‐phenoxymethyloxetane at once. The temperature changes in the polymerization depended on the polymerization rates. That is, a fast polymerization was exothermic, increasing the temporal temperature of the polymerization by approximately 130 °C within a few minutes. Infrared thermography, which can analyze multiple samples instantaneously, proved effective as a screening method for thermally latent curing systems. Exothermicity in the crosslinking polymerization of 1,4‐bis(3‐ethyloxetanylmethoxy)benzene was also analyzed by infrared thermography. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5519–5524, 2006 相似文献
153.
Hideo Nemoto Hiroshi Kurobe Masataka Ihara Keiichiro Fukumoto Tetsuji Kametani 《Tetrahedron letters》1984,25(29):3095-3098
A convergent and stereoselective synthesis of vitamin D3 was achieved via 3,5-cyclovitamins D3 (20) which were prepared from the chiral aldehyde (2) and the vinyl bromide (12) derived from Grundmann's ketone. 相似文献
154.
The catalytic activity of horseradish peroxidase (HRP) in the presence of hydrogen peroxide has been investigated for the fluorescent derivatization of kynurenic acid under conditions with no exposure to light. Non-fluorescent kynurenic acid was converted into a fluorescent compound (Ex: 367 nm, Em: 470 nm) with HRP in the presence of hydrogen peroxide, and the optimum conditions of this fluorescent derivatization were investigated. Moreover, this fluorescent derivatization was developed for a spectrofluorometric determination of trace amounts of kynurenic acid by measuring the fluorescence intensity of the fluorescent compound. The calibration curve obtained was linear from 1.0 to 10.0 nmol of kynurenic acid in a 1.0 mL sample solution. The relative standard deviation at 5.0 nmol of kynurenic acid was 5.71% (n=5). By adjusting the bandwidths for both the excitation and emission to 15 nm, the calibration curve was also linear in the range between 0.1 to 1.0 nmol of kynurenic acid in a 1.0 mL sample solution. This method was applied to the fluorometric determination of trace amounts of kynurenic acid in the control sera. 相似文献
155.
In this paper, we propose a fully polynomial-time randomized approximation scheme (FPRAS) for a closed Jackson network. Our
algorithm is based on the Markov chain Monte Carlo (MCMC) method. Thus our scheme returns an approximate solution, for which
the size of the error satisfies a given bound. To our knowledge, this algorithm is the first polynomial time MCMC algorithm
for closed Jackson networks with multiple servers. We propose two new ergodic Markov chains, both of which have a unique stationary
distribution that is the product form solution for closed Jackson networks. One of them is for an approximate sampler, and
we show that it mixes rapidly. The other is for a perfect sampler based on the monotone coupling from the past (CFTP) algorithm
proposed by Propp and Wilson, and we show that it has a monotone update function. 相似文献
156.
Yutaka Ando Tomomi Hanada Kumiko Saitoh 《Journal of Polymer Science.Polymer Physics》1994,32(1):179-185
Dielectric and thermal characterizations were performed for poly (vinylidene fluoride) (PVDF)/poly (ethyl methacrylate) (PEMA) blends of different composition. The characteristics of PVDF β relaxation were shown to be little affected in the semicrystalline blends with PEMA. The relaxation strength, however, depends strongly on the PEMA content and a linear relation was found between the intensity of the β relaxation and the weight fraction of the PVDF crystal-amorphous interphase. Phase structures of the PVDF/PEMA blends are also proposed. © 1994 John Wiley & Sons, Inc. 相似文献
157.
S. Nemoto 《Optical and Quantum Electronics》1984,16(2):165-171
This paper presents an accurate method for observing fringe movement in a Mach-Zehnder type fibre interferometer. We place a photodetector in each of two interference patterns formed by a half-mirror and waves emitted from single-mode fibres. By applying the output voltages of the detectors to X- and Y-terminals of an oscilloscope, we can observe the fringe movement as a rotation of a bright spot along a Lissajous figure. 相似文献
158.
Tadamasa Nemoto Kensuke Naka Yoshiki Chujo 《Journal of polymer science. Part A, Polymer chemistry》2008,46(8):2864-2868
To study the bidentate coordination effect on the polycondensation of L ‐valinates between metal triflates as a Lewis acid and methoxy groups, we carried out the polycondensation of 2‐methoxy‐4‐nitrophenyl L ‐valinate ( 1a ) and 2‐methoxyphenyl L ‐valinate ( 1b ) in the presence of the various kinds of rare‐earth triflates in DMF solution at room temperature. The polymerizations of 1a did not proceed without any metal triflates. In the presence of 5 mol% triflates, especially Sc(OTf)3, the polymerization proceeded effectively. After the reaction mixture was poured into water, the product was collected, which was recognized as poly(L ‐valine)s by FTIR spectrum and GPC measurement. The yield of the product from the polymerization of 1a with Sc(OTf)3 was higher than that from the polymerization of 4‐nitrophenyl L ‐valinate ( 1c ) with Sc(OTf)3. This result indicates that the polymerization of 1a was promoted to introduce the methoxy group on the o‐position of the phenyl ring at the ester group with the aim of the bidentate coordination effect between metal triflates and L ‐valinate. As a control experiment, we carried out the polycondensation of 1b in the presence of 5 mol% metal triflates; however, any polymerization did not proceeded. That reason is from the lower activity of activated L ‐valinate ( 1b ). © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 2864–2868, 2008 相似文献
159.
Hirofumi Fujimoto Miroslav Pinak Toshiyuki Nemoto Juraj Kotulic Bunta 《Central European Journal of Physics》2007,5(1):49-61
Classical molecular dynamics methods were used to analyze the importance of 8-oxoguanine (8-oxoG) pairing with other DNA bases
in order to determine the impact of oxidative guanine lesions on DNA structure. Six lesioned molecules, each containing 8-oxoG
mispaired with one of the four normal bases on the the opposite strand at the center of 40-mer DNA, and one non-damaged DNA
molecule, were simulated for 2 nanoseconds of real time. The 8-oxoG lesioned bases were found to incorporate opposite all
normal bases. There are observed conformational and energetical differences among these parings. 8-oxoG in anti-form creates
firm hydrogen bonds with cytosine and this bonding has a strong attractive electrostatic interaction energy similar to that
of a native base pair-guanine to cytosine. Meanwhile, it does not form a stable base pair with purine bases (adenine and guanine)
nor with the pyrimidine base thymine. On the other hand, the 8-oxoG in syn-form was found to pair with adenine.
相似文献
160.
[figure: see text] A reliable and rigid spacer, trans,trans,trans-perhydronaphthacene, for molecular tweezers was designed. A synthesis and molecular recognition study of its 1,14-disubstituted derivatives was carried out. 相似文献