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61.
62.
Ikeda A Sato T Kitamura K Nishiguchi K Sasaki Y Kikuchi J Ogawa T Yogo K Takeya T 《Organic & biomolecular chemistry》2005,3(16):2907-2909
Various types of lipid membrane-incorporated C60 with high C60 concentrations can be prepared easily in several hours using the C60 exchange method and the photocleaving activity of cationic lipid membrane-incorporated C60 was appreciably higher than that of the C60.gamma-CDx complex. 相似文献
63.
The effect of co-catalyst (ZnO or ZrO2) has been tested for hydrogenation of CO2 on CuO/TiO2 and CuO/Al2O3. CuO−ZnO/TiO2 catalyst showed the highest activity for methanol synthesis. Kinetic parameters were also determined. 相似文献
64.
Kohei Sanui Tomohiko Asahara Naoya Ogata 《Journal of polymer science. Part A, Polymer chemistry》1968,6(5):1195-1207
Acrylates, such as ethyl acrylate, add with amino alcohol to form N-(hydroxyalkyl) β-alanine ester and room-temperature polycondensation follows, forming polyamide in the presence of a basic catalysts, such as alkali metal alkoxide. The reaction medium has an influence on the course of the polycondensation; that is, N-(hydroxyalkyl) polyamide is formed in methanol solution and polyamide ether in other solvents, such as tetrahydrofuran. These two courses of the room-temperature polycondensation have been studied, and the reaction mechanism is discussed in this paper. 相似文献
65.
66.
Yasushi Joh Yahide Kotake Toshio Yoshihara Fumio Ide Kazuo Nakatsuka 《Journal of polymer science. Part A, Polymer chemistry》1967,5(3):605-617
Stereospecific polymerization of methacrylonitrile with diethylmagnesium has been studied. Polymerization temperature has an important effect on polymerization. The conversion, stereoregularity, and intrinsic viscosity of the polymer increased significantly with increasing polymerization temperature. Stereoregularity of the polymer improved with increasing the polymerization time and the monomer concentration, but it is independent of the catalyst concentration. Intrinsic viscosity of the crystalline polymer increased with increasing monomer concentration but is independent of the polymerization time and the catalyst concentration. It is suggested that two mechanisms are involved in this polymerization: coordinated anionic polymerization to from the crystalline polymer, and probably conventional anionic polymerization to form the amorphous polymer. It is found that crystalline polymer can also be obtained in homogeneous phase such as in tetrahydrofuran solvent. 相似文献
67.
Chen CH Yamaguchi T Sugawara K Koga K 《The journal of physical chemistry. B》2005,109(44):20669-20672
The oxidation process of Cu nanoparticles has been investigated by means of an in-situ X-ray diffraction method. A self-limiting oxidation process involving an unusually drastic decrease (about 4 orders in magnitude) in the oxidation rate was observed at 298 K, whereas a non-self-limiting oxidation emerged at 323 K with a rate of at least 4 orders in magnitude faster than 298 K. The drastic slowing at 298 K and the big differences between the two close temperatures in the oxidation kinetics were found to be directly correlated to whether the compressive stress in the Cu(2)O(111) layers that commensurately formed on the Cu(111) surface is relaxed or not. 相似文献
68.
An analytical method was established for the determination of benzene and 13 of its alkyl derivatives. The method was applied to a survey of indoor pollution that investigated the usefulness of the method, concentration levels, seasonal variations, profiles, correlations between compounds, and factors that affected indoor pollution by these compounds. The survey was performed in 21 houses in the summer of 1999 and 20 houses in the winter of 1999-2000 in Fuji, Japan. All the target compounds were detected in the indoor and outdoor air of all houses. Outdoor concentrations of benzene ranged from 0.779 to 3.17 microg/m3 in summer and from 1.35 to 6.04 microg/m3 in winter, whereas indoor concentrations of benzene ranged from 0.694 to 3.11 microg/m3 in summer and from 1.65 to 6.89 microg/m3 in winter. Indoor concentrations of the target compounds, except for benzene, were elevated, compared with outdoor concentrations. Because indoor and outdoor concentrations of benzene and its derivatives in summer were lower than in winter, the emission of these compounds may be increased by use of a heater and other variables present in winter. Profiles of the compounds, correlations between the compounds, and factors that affected indoor pollution (determined by multiple regression analysis) were investigated. These results suggested that indoor benzene predominantly penetrated from outdoors and that other benzene derivatives were emitted from indoor sources, such as paint solvents and kerosene heaters. 相似文献
69.
We investigated the Diels-Alder reactions of maleic anhydrides embedded in a dibenzobicyclo[2.2.2]octatriene motif as a nonsterically biased dienophile. Substituents on a benzene ring in these dienophiles are far from the reaction center, providing a sterically equivalent pi-face. Instead substituents can unsymmetrize the dienophilic pi face through pi (anhydride)-pi (aromatic) orbital interactions. Electron-withdrawing substituents affect the facial bias and relative rates of these cycloadditions. The preference of the cycloadditions is opposite in direction to those observed in nucleophilic additions of 2-substituted-9,10-dihydro-9,10-ethanoanthracen-11-ones (dibenzobicyclo[2.2.2]octadienones) and in electrophilic additions of 2-substituted 9,10-dihydro-9,10-ethenoanthracenes (dibenzobicyclo[2.2.2]octatrienes), though all of them have related dibenzobicyclic systems. 相似文献
70.
Shuji Kondo Masashi Kadowaki Masahito Mase Tomohiko Kakuno Hideo Kunisada Yasuo Yuki 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(5):315-322
Abstract A new monomer containing two replaceable groups, 2,4-dichloro-6-(p-vinylphenyl)-1,3,5-triazine (DCVT) was prepared by the reaction of p-vinylphenylmagnesium chloride with cyanuric chloride. This monomer was polymerized readily in benzene by AIBN at 60°C. From the copolymerization with styrene, Q and e values of DCVT were obtained as Q = 2.42 and e = 0.08. An insoluble terpolymer prepared from DCVT, styrene, and divinylbenzene was treated with several nucleophilic reagents, including sodium methoxide, sodium methylmercaptide, dimethylamine, and triethylphosphite, to afford the corresponding polymers in high conversions. 相似文献