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111.
Maki Itoh Toshimitsu Suzuki Yoshihiko Tsujimoto Ken-ichi Yoshii Yoshinobu Takegami Yoshihisa Watanabe 《Fuel》1983,62(1):98-102
Thermal cracking of tar-sand bitumens has been carried out using a two-stage pyrolysis reactor with temperature zones of 440°C and 750–800°C, respectively. Feedstocks were pyrolysed in the first stage into cracked oils, which were carried to the second stage for subsequent pyrolysis. Only 12–14 wt% of ethylene was obtained from tar-sand bitumens at the residence time of 1.2 s in the second stage, although 27 and 16 wt% were obtained from Taching and Iranian heavy vacuum residues, respectively. The tar-sand bitumens contain shorter paraffinic straight-chains and have more branched molecules than the vacuum residues of petroleum. A straight-chain paraffin index is proposed, with which a good correlation was obtained between ethylene yield and the fraction of straight-chain paraffin carbons in the heavy oil. 相似文献
112.
Seiichi Suenaga Masako Nakahashi Miho Maruyama Takayuki Fukasawa 《Journal of the American Ceramic Society》1997,80(2):439-444
Wetting and brazing studies of sputtering-deposited, submicrometer thin film filler metal in an Ag—Cu—Ti/Al2 O3 system were performed. The interfacial reaction layer between the filler metal and Al2 O3 was investigated. It is possible to make a brazing joint even with a reaction layer of less than 100 nm thickness. Different types of interfacial reaction layers were observed when the Ti content in the filler metal was varied. The Cu—Ti—O system compounds were observed in the samples with high wetting capabilities, but not in the sample with low wetting characteristics. It was found that these compounds are substances that promote effective brazing. 相似文献
113.
T. Watanabe P. Chairoj H. Tsuruta W. Masarngsan C. Wongwiwatchai S. Wonprasaid W. Cholitkul K. Minami 《Nutrient Cycling in Agroecosystems》2000,57(1):55-65
Nitrous oxide (N2O) emission from fertilized maize fields was measured using a closed chamber at four experimental sites in Thailand. The average measured N2O flux from unfertilized plots through crop season was 4.16 ± 1.52, 5.05 ± 1.65, 5.25 ± 1.68 and 6.74 ± 2.95 g N2O-N m-2 h-1, at Nakhon Sawan, Phra Phutthabat, Khon Kaen and Chiang Mai, respectively. Increased N2O emissions by the application of nitrogen fertilizer were 0.22–0.44, 0.19–0.38%, 0.12–0.24 and 0.08–0.15% of the applied N, respectively. Compared to other data, N2O emission rate to applied nitrogen was not significantly different between the data of Thailand and the Temperate Zone. 相似文献
114.
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116.
Lithium naphthalene reacts with acetic acid to give α-anion of lithium acetate. The reaction of this anion with various ketones gives the corresponding β-hydroxy-acids in good yield. 相似文献
117.
Masaru Takahashi Tetsu Nakatani Shinji Iwamoto Tsunenori Watanabe Masashi Inoue 《Applied catalysis. B, Environmental》2007,70(1-4):73-79
The solvothermal reaction of mixtures of aluminum isopropoxide (AIP) and gallium acetylacetonate (Ga(acac)3) directly yielded the mixed oxides of γ-Ga2O3-Al2O3. In the solvothermal synthesis, the crystal structure of mixed oxides was controlled by the initial formation of γ-Ga2O3 nuclei. The mixed oxides prepared in diethylenetriamine have extremely high activities for selective catalytic reduction (SCR) of NO with methane as a reducing agent. With increasing crystallite size of the spinel structure, the catalytic activity increased. The ratio of the amount of methane consumed by combustion to total methane conversion was proportional to the density of acid sites on the surface of the mixed oxides. The mixed oxide catalysts prepared in diethylenetriamine had lower densities of acid sites and showed a higher methane-efficiency for CH4-SCR than those prepared in other solvents. These catalysts maintained their high activity even when the reaction was carried out under the severe conditions (i.e., high space velocity and low NO concentration). 相似文献
118.
Single-walled carbon nanotube networks grown on SiO2 pillars were studied by means of scanning photoemission microscopy. The individual nanotubes or nanotube bundles growing from the pillar tops were observed in C 1s images. Band bending near catalytic Fe/nanotube contacts in an end-bonded configuration was studied by measuring C 1s spectra along the tube axes. Within our experimental resolution, no band bending was observed. This implies that the depletion width is less than the spatial resolution of the scanning photoemission microscope (90 nm) or that the amount of the band bending is less than 0.1 eV. 相似文献
119.
A process for electroplating amorphous gold-nickel alloy with the atomic ratio of unity was developed. The plating bath was prepared by adding potassium cyanoaurate(I) into a known plating bath which produces amorphous nickel-tungsten alloy. At a sufficiently high gold concentration, the alloy deposit did not contain any tungsten. The amorphous nature of the Au-Ni alloy produced in the new bath was confirmed by using TEM and THEED. Hardness, resistivity, and contact resistance of this new alloy were determined, and the results are discussed for applications as an electrical contact material. 相似文献
120.
The crystalline complex between poly(γ-methyl l-glutamate) (PMLG) and dimethyl phthalate (DMP) has been formed in films cast from a solution in dichloroethane. It has the stoichiometry of 1 mol of DMP to three or four residues of PMLG and shows two definite characteristics in X-ray diffraction patterns; one is the large hexagonal unit cell with the edge of around 28 Å and another the ‘extra’ 5.07 Å meridional reflection which can not be interpreted by a PMLG α-helical conformation. The structural examination for the films with various DMP contents is carried out by X-ray, viscoelastic, and d.s.c. measurements and the following structure is proposed for the crystalline complex. Four PMLG are associated to form a group which is hexagonally packed and DMP molecules, located in the gaps between groups, form a specific favourable helical structure along PMLG chains in which the van der Waals stacking of benzene rings of DMP is significant. 相似文献