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排序方式: 共有325条查询结果,搜索用时 546 毫秒
311.
Tomoaki Watanabe Yasuhiko Sakai Kouji Nagata Osamu Terashima Takashi Kubo 《Experiments in fluids》2012,53(5):1369-1383
This paper presents a new experimental approach for simultaneous measurements of velocity and concentration in a turbulent liquid flow with a chemical reaction. For the simultaneous measurements, we developed a combined probe consisting of an I-type hot-film probe and an optical fiber probe based on the light absorption spectrometric method. In a turbulent planar liquid jet with a second-order chemical reaction $(\mathrm{A}+\mathrm{B}\rightarrow \mathrm{R})$ , streamwise velocity and concentrations of all reactive species are measured by the combined probe. The turbulent mass fluxes of the reactive species are estimated from the simultaneous measurements. The results show that the influence of the chemical reaction on the turbulent mass flux of the reactant species near the jet exit is different from its influence in other regions, and the turbulent mass flux of the product species has a negative value near the jet exit and a positive value in other regions. 相似文献
312.
Yamamoto Y Saigoku T Nishiyama H Ohgai T Itoh K 《Organic & biomolecular chemistry》2005,3(9):1768-1775
In the presence of catalytic amounts of Cp*RuCl(cod), the partially intramolecular cyclotrimerizations of various C-alkynylglycosides and C-diynylglycosides proceeded at ambient temperature to afford C-arylglycosides. 相似文献
313.
Yamamoto Y Kinpara K Saigoku T Nishiyama H Itoh K 《Organic & biomolecular chemistry》2004,2(9):1287-1294
In the presence of a catalytic amount of Cp*RuCl(cod), 1,6- and 1,7-diynes connected by an amide or an ester tether underwent cycloaddition with terminal alkynes at room temperature to give rise to cycloadducts in 40-93% yields with 63 : 37-83 : 17 regioisomer ratios. 相似文献
314.
Yamamoto Y Saigoku T Ohgai T Nishiyama H Itoh K 《Chemical communications (Cambridge, England)》2004,(23):2702-2703
In the presence of catalytic amounts of Cp*RuCl(cod), the cycloaddition of 1,6-diynes with various C-alkynylglycosides proceeded at ambient temperature to afford C-arylglycosides in 46-93% yields. 相似文献
315.
Kiyoshi Endo Tomoaki Sugita 《Journal of polymer science. Part A, Polymer chemistry》2004,42(12):2904-2910
Copolymerization of styrene (St) and St‐terminated poly(ethylene oxide) macromonomer (SEOM) with CpTiCl3/methylaluminoxane (MAO) catalyst in toluene was investigated. The copolymerization of St and SEOM proceeded easily to give a graft copolymer consisting of syndiotactic polystyrene as the main chain and hydrophilic poly(ethylene oxide) as the side chain. A number of side chains in the graft copolymer could be controlled by the amount of SEOM in the feed. The reactivity of SEOM was determined from copolymerization of St and SEOM with the CpTiCl3/MAO catalyst, and the reactivity of SEOM depended on the molecular weight of SEOM. The thermal properties of the graft copolymer such as the melting temperature were influenced by the introduction of SEOM. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2904–2910, 2004 相似文献
316.
Thomas H. Barnes Tomoaki Eiju Shigeru Kokaji Kiyofumi Matsuda Narihiro Yoshida 《Optical Review》1995,2(2):103-105
A novel, parallel aligned optically addressed liquid crystal spatial light modulator has been used to implement an optically writable image memory. The memory uses a two-beam interferometer with optical feedback which exhibits thresholding, hysteresis, and bistability. We discuss the characteristics of the system, and present the results of an experimental demonstration.Presented at the International Commission for Optics Topical Meeting, Kyoto, 1994. 相似文献
317.
Takuya Okazaki Hiroaki Taniguchi Hajime Wagata Mizuki Ito Hideki Kuramitz Tomoaki Watanabe 《Electroanalysis》2020,32(8):1681-1688
We present a novel zinc oxide (ZnO) optically transparent electrode (OTE) prepared by the spin‐spray technique for spectroelectrochemistry. The spin‐spray technique can deposit ZnO film at a low cost, high rate deposition, and at a low temperature (<100 °C) in a single step. This new technique provides good optical transparency and electrical conductivity for ZnO. The electrochemical and spectroelectrochemical properties of the ZnO electrode were investigated for varying thicknesses of ZnO using methylene blue as a redox indicator. A ZnO OTE chip that includes three electrodes on a glass chip was developed for thin‐layer spectroelectrochemistry. Moreover, the ZnO films were successfully applied in an electrochemical‐localized surface plasmon resonance (LSPR) method for methylene blue detection by using them as a transparent conducting substrate for loading gold nanoparticles. 相似文献
318.
A Sinc-collocation scheme for Fredholm integral equations of the second kind was proposed by Rashidinia–Zarebnia in 2005.
In this paper, two improved versions of the Sinc-collocation scheme are presented. The first version is obtained by improving
the scheme so that it becomes more practical, and natural from a theoretical view point. Then it is rigorously proved that
the convergence rate of the modified scheme is exponential, as suggested in the literature. In the second version, the variable
transformation employed in the original scheme, the “tanh transformation”, is replaced with the “double exponential transformation”.
It is proved that the replacement improves the convergence rate drastically. Numerical examples which support the theoretical
results are also given. 相似文献
319.
Electron-donating molecular tips were used for the observation of single-walled carbon nanotubes (SWNTs). Defects in SWNTs were selectively visualized at the atomic scale on the basis of charge-transfer interaction with the molecular tip. 相似文献
320.