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101.
Masaru Takahashi Noriyuki Inoue Tatsuya Takeguchi Shinji Iwamoto Masashi Inoue Tsunenori Watanabe 《Journal of the American Ceramic Society》2006,89(7):2158-2166
The reaction of mixtures of aluminum isopropoxide and gallium acetylacetonate in 1,4-butanediol or 1,5-pentanediol at high temperatures (glycothermal reaction) directly gave the γ-Ga2 O3 –Al2 O3 solid solutions, which had high catalytic activities for selective reduction of NO using methane as the reducing agent. However, the reaction with a higher Al/(Ga+Al) charged ratio yielded the glycol derivative of boehmite as a by-product and the catalytic activity of the solid solution decreased. Therefore, synthesis of the solid solution using various glycols was examined and it was found that solid solutions with high Al contents without contamination of the glycol derivative of boehmite were obtained by using 1,6-hexanediol as a reaction medium. The solid solution exhibited a higher NO conversion than that synthesized in other glycols. 相似文献
102.
Poly(vinyl chloride) (PVC) with one or more metal salts added was colored by the action of heat to investigate the stabilization mechanism. The coloration and the color difference of heated PVC compound films varied according to the metal salt added. The decoloration of the colored compound films was advanced markedly in THF, DMF, acetone, and ammonia. On the other hand, the heated achromatic PVC film containing Cd/Ba soaps underwent an opposite change, from colorless to yellow orange, in the above materials. This means that the coloration of heated compound films may result from the formation of some complex (for example, π complex of the polyene with the metal chloride). Furthermore, the colored film with cadmium stearate was decolored by roll mixing with the colored film containing barium stearate. These results indicate that the stabilization with metal soaps may be founded on a physical phenomenon such aa an effect of complementary color. 相似文献
103.
Summary This paper describes the so-called No Catalyst Copolymerization between dioxo-1,1-thiazetidine-1,2(Ethanesultam; ESm) and 2-methyl-2-oxazoline. The copolymerization took place without any added initiator to produce copolymers of MeOZO and ESm. The structure of the copolymer was determined by the IR and NMR spectra, elemental analysis, as well as by the result of an alkaline hydrolysis of the copolymer. The reaction scheme of the copolymerization via zwitterion mechanism (Eq 3–5) was proposed. 相似文献
104.
Two problems were solved theoretically on the heat transfer to circular tube flow with internal heat source. The one problem is to maintain the mixed-mean temperature of fluid at the inlet temperature. The other is a conjugated problem with a uniformly specified temperature at the outside surface of the wall, accounting for the wall conduction. From the numerical example for the former, it is shown that the mixed-mean temperature can be controlled within 15% error under the estimated condition. From the numerical results for the latter, it is concluded that the influence of wall conduction is more serious than the case without heat generation. 相似文献
105.
Hideo Inoue 《Polymer》1973,14(10):502-504
A sedimentation equilibrium equation was derived in weight-per-volume concentration units to evaluate the degree of preferential binding of one solvent component to a homogeneous neutral macromolecule in a mixture of two components. Using the equation, the preferential binding of chloroethanol to β-lactoglobulin A was calculated from sedimentation equilibrium data, and the result showed good agreement with values obtained by light scattering and refractive index increment experiments. It was also demonstrated that the preferential interaction can in principle be determined by density increment measurements under different conditions: at constant molality and at constant chemical potential of solvent. 相似文献
106.
Masaaki Takehisa Hiromasa Watanabe Hirondo Kurihara Kouichi Yamaguchi Hayato Nakajima Toshiaki Yagi Terutaka Watanabe Takanobu Sugo Takeshi Suwa Shinsaku Maruyama Atsuro Kodama Takeo Shimada Yoshio Maruyama Masamichi Tohei Takeshi Wada Sueo Machi 《应用聚合物科学杂志》1979,24(8):1831-1844
Radiation-induced polymerization of ethylene using aqueous tert-butyl alcohol as medium was carried out in a large-scale pilot plant with a 50-liter central source-type reactor at a pressure of 105 to 395 kg/cm2, temperature of 30° to 80°C, mean dose rate of 4.5 × 104 to 1.9 × 105 rads/hr, ethylene feed rate of 5.5 to 23.5 kg/hr, and medium feed rate of 21 to 102 l./hr. The space–time yield and molecular weight of the polymer were in the range of 4.7 to 16.8 g/l.-hr and 1.3 × 104 to 8.9 × 104, respectively. The space–time yield and molecular weight increased with mean residence time at 30°C, whereas at 80°C they became almost independent of the time. The space–time yield increased with pressure and dose rate, slightly decreased with temperature, and was maximum at ethylene molar fraction of 0.5. The polymer molecular weight increased with pressure and ethylene molar fraction, and decreased with dose rate and temperature. The total amount of deposited polymer on the reactor wall, source case wall, and scraping blades was usually less than 1 kg, which was negligibly small for the analysis of polymerization. Continuous discharge of the polymer slurry and production of fine-powder polyethylene were successfully carried out. In the central source-type reactor, a dose rate of 1.9 × 105 rads/hr was obtained with a 60Co source of ca. 12 kCi. 相似文献
107.
Akihisa Inoue 《北京科技大学学报(英文版)》2010,17(2):208-213
The unusual glass-forming ability(GFA) of the Zr_(48)Cu_(36)Ag_8Al_8 alloy and the high ductility of the Zr_(48)Cu_(36)Ag_8Al_8 metallic glass-matrix composites containing Ta powder were reported.The bulk metallic glass rod with a diameter of 25 mm was successfully synthesized using copper mold casting for the Zr_(48)Cu_(36)Ag_8Al_8 alloy.High GFA of this alloy was found to be related to a large supercooled liquid region and a quaternary eutectic point with low melting temperature.The bulk metallic glass... 相似文献
108.
Takashi Inoue 《Carbon》2007,45(11):2164-2170
Iron-based nanoparticles, centrifugally classified by size, with variation of subnanometer order, have been used for the growth of diameter-controlled carbon nanotubes (CNTs) for the first time via catalytic chemical vapor deposition. The centrifugal classification of nanoparticles is facilitated by fractional precipitations through the sequential addition of ethanol to a hexane solution containing the nanoparticles. Three different nanoparticle sizes were obtained, which have average diameters and standard deviations of 3.9 ± 0.8 nm, 3.3 ± 0.6 nm, and 2.8 ± 0.4 nm. By the classification process of nanoparticles, the standard deviation of the average diameter of the fractionated nanoparticles decreased by around one half of that of the as-synthesized nanoparticles. In addition, we demonstrate a technique for estimating the average diameter of each classified nanoparticle using conventional low-angle X-ray diffraction, without the need for time-consuming TEM observation and analysis. From the three classified nanoparticle sizes, with average diameters of 2.8, 3.3, and 3.9 nm, CNTs with average diameters of 3.1, 3.6, and 4.5 nm were obtained by changing growth temperatures, respectively. Therefore, centrifugally classified nanoparticles are one of the most promising ‘seeds’ for use in the diameter-selective growth of CNTs. 相似文献
109.
H. Kominami J. Kato Y. Takada Y. Doushi B. Ohtani S. Nishimoto M. Inoue T. Inui Y. Kera 《Catalysis Letters》1997,46(3-4):235-240
Thermal decomposition of titanium(IV) tetra-tert-butoxide (TTB) in inert organic solvents at 573 K yielded microcrystalline
anatase (titanium(IV) oxide, TiO2) powders with a crystallite size of ca. 9 nm and a surface area of <100 m2 g-1. Primary and secondary alkoxides of titanium(IV), however, were not decomposed under similar conditions, indicating that
the thermal stability of C-O bonds in the alkoxides was a decisive factor for their decomposition. The TiO2 prepared from TTB by this manner was thermally stable upon calcination in air and retained high surface area of ca. 100 m2 g-1 even after calcination at 823 K. The as-prepared TiO2 powders, without calcination, exhibited much higher rate of carbon dioxide formation than any other active photocatalysts
such as Degussa P-25 and Ishihara ST-01 in the photocatalytic mineralization of acetic acid in aerated aqueous solutions.
The higher activity of the present TiO2 photocatalysts is attributed to both high crystallinity and large surface of the present product. The calcination of the
as-prepared TiO2 in air reduced the photocatalytic activity, but it was still higher than the other commercially available TiO2's.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
110.
Reactive blending of polyamide 6 (PA) with polyethylene (PE) having reactive sites, maleic anhydride (MAH content=0.1 wt%),and glycidyl methacrylate (GMA content=3-12 wt%), was carried out at 70/30 and 65/35 (PA/PE) blend ratios. Blend morphology evolved by reactive blending was analyzed by light scattering and transmission electron microscopy. The blends were then irradiated by electron beam. The degree of crosslinking was estimated by measuring the dynamic storage modulus at a temperature above melting point of PA. It was found that surface-to-surface interparticle distance τ was significantly reduced by the micelle formation via pull-out of in situ-formed graft copolymers. The blend with shorter τ was crosslinked by electron-beam irradiation at the lower dose level. A blend having the minimum τ (∼0.2 μm) was nicely crosslinked at a low dose level same as for PE, and even for the PA matrix system. 相似文献