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排序方式: 共有389条查询结果,搜索用时 15 毫秒
1.
The In-site of Ba2In2O5 with Brownmillerite structure was partially substituted for Ce4+ ions in order to examine the doping effect on the order-disorder transition. Ba2In2 – x
Ce
x
O5 + x/2 (x = 0.1, 0.2, 0.3, 0.5, 1.0, and 1.5) were prepared by solid state reaction. X-Ray diffraction analyses of these powder samples demonstrated that Ba2In2 – x
Ce
x
O5 + x/2 (x = 0.1 and 0.2) possesses Brownmillerite structure. With increasing content of Ce4+ ion the crystal system of Ba2In2 – x
Ce
x
O5 + x/2 (x = 0.3, 0.5, and 1.0) changed to cubic perovskite structure above the order-disorder transition temperature of Ba2In2O5. Arrhenius plots of the electrical conductivities of Ba2In2 – x
Ce
x
O5 + x/2 (x = 0.2, 0.3, and 1.0) exhibited no discontinuity. These compounds had high transference numbers of oxide ion above 973 k. 相似文献
2.
Gas absorption accompanied by an instantaneous irreversible chemical reaction into laminar falling films of power-law liquids was studied theoretically. The convective-diffusion equations for a solute gas and a liquid-phase reactant were solved numerically and the numerical solution for the reaction factor was obtained as a function of the Graetz number, the concentration ratio, the diffusivity ratio and the power-law index of the liquid. 相似文献
3.
4.
K Yoshida Y Takamatsu Y Adachi M Kishi H Sekine T Shigematsu 《Canadian Metallurgical Quarterly》1996,37(2):55-62
Endoglucanase production was measured in culture filtrates of four species of Saccobolus growing in media containing glucose or crystalline cellulose as the only carbon sources. Enzyme activity was four to seven times higher in the presence of cellulose than glucose. S. saccoboloides showed maximal growth and enzyme production. The extracellular proteins secreted during growth on cellulose were separated by polyacrylamide gel electrophoresis and stained for proteins. A zymogram technique was used to visualize bands with endoglucanase activity. The four species showed different protein and isoenzyme patterns. 相似文献
5.
Yoshiyuki Uno Akira Okada Kensuke Uemura Purwadi Raharjo Toshihiko Furukawa Kosaku Karato 《Precision Engineering》2005,29(4):171-455
A new finishing process for metal molds by large-area electron beam (EB) irradiation is proposed in this study. In the large-area EB irradiation equipment used here, an EB with high-energy density is irradiated without focusing the beam, and so the EB with a maximum diameter of 60 mm can be used for melting or evaporating metal surface instantly. Experimental results show that the surface roughness decreases from 6 μmRz to less than 1 μmRz in just a few minutes under proper machining conditions. The corrosion resistance of metal mold surface also could be greatly improved by large-area EB irradiation. Furthermore, the surface roughness of tilting surface close to 90° could be well improved. Therefore, large-area EB irradiation method has a possibility to become a high-efficiency finishing process for metal molds. 相似文献
6.
Yoshiro Nakamura Akira Watanabe Kunio Mori Kosaku Tamura Michio Inagaki 《Journal of Materials Science》1986,21(12):4485-4488
A binary blend which consists of two incompatible polymers such as poly(vinyl chloride) and polyethylene has been performed through a partial co-crosslinking reaction with peroxide to give a co-crosslinked blend with a uniform dispersion of small polyethylene particles and with an improved mechanical property. The results are obtained through the formation of a co-crosslinked product which acts as a potential solid phase dispersant as well as a well-bonded reinforcing interlayer on polyethylene particles uniformly dispersed in poly(vinyl chloride) matrix. The resulting blends (PVC/PE=10/90 wt) give carbon spherules of 0.5 to 1m diameter through pressure-carbonization at 650° C for 1 h. 相似文献
7.
The present study was carried out to examine if the positional distribution of medium-chain fatty acid (MCF) in dietary synthetic
fat influences lymphatic transport of dietary fat and the chemical composition of chylomicrons in rats with permanent cannulation
of thoracic duct. Four types of synthetic triacylglycerol were prepared: (i) sn-1(3) MCF-sn 2 linoleic acid, (ii) interesterified sn-1(3) MCF-sn 2 linoleic acid, (iii) sn-2 MCF-sn-1(3) linoleic acid, and (iv) interesterified sn-2 MCF-sn-1(3) linoleic acid. A purified diet composed of equal amounts of the synthetic fat and cocoa butter was given to rats with
permanent lymph duct cannulation. The positional distribution of MCF in the dietary fat had no significant effect on the lymph
flow, triacylglycerol output, phospholipid output, lipid composition of chylomicrons, or the particle size. The positional
distribution of MCF in the synthetic triacylglycerol was maintained in the chylomicron triacylglycerol. These results showed
that MCF in the dietary triacylglycerol is transported into lymphatics and the positional distribution is well preserved in
chylomicron triacylglycerol. 相似文献
8.
Shiro Torizuka Kaoru Sato Hiroaki Nishio Teruo Kishi 《Journal of the American Ceramic Society》1995,78(6):1606-1610
Compacts of TiB2 with densities approaching 100% are difficult to obtain using pressureless sintering. The addition of SiC was very effective in improving the sinterability of TiB2 . The oxygen content of the raw TiB2 powder used in this research was 1.5 wt%. X-ray photoelectron spectroscopy showed that the powder surface consisted mainly of TiO2 and B2 O3 . Using vacuum sintering at 1700°C under 13–0.013 Pa, TiB2 samples containing 2.5 wt% SiC achieved 96% of their theoretical density, and a density of 99% was achieved by HIPing. TEM observations revealed that SiC reacts to form an amorphous phase. TEM-EELS analysis indicated that the amorphous phase includes Si, O, and Ti, and X-ray diffraction showed the reaction to be TiO2 + SiC → SiO2 + TiC. Therefore, the improved sinterability of TiB2 resulted from the SiO2 liquid phase that was formed during sintering when the raw TiB2 powder had 1.5 wt% oxygen. 相似文献
9.
Equilibria between CaO-TiOx or CaO-Al2O3-TiOx melts and liquid iron with respect to O, N and S were studied at 1873 K as a function of Ti (or Al) content in metal, using a CaO or an Al2O3 crucible. The Al-O and Ti-O relations in liquid iron were studied, and nitride and sulfide capacities defined by and , respectively, were obtained from nitrogen and sulfur distribution ratios, coupled with the analyzed oxygen content in liquid iron or the PO2 determined by Ti/TiO2 equilibrium. Based on these results, activities of Al2O3 and activity coefficients of TiO2 and TiO1.5 were evaluated. 相似文献
10.
Yuki Akinaga Tokuhisa Kawawaki Hinano Kameko Yuki Yamazaki Kenji Yamazaki Yuhi Nakayasu Kosaku Kato Yuto Tanaka Adie Tri Hanindriyo Makito Takagi Tomomi Shimazaki Masanori Tachikawa Akira Yamakata Yuichi Negishi 《Advanced functional materials》2023,33(33):2303321
Single-atom (SA) catalysts exhibit high activity in various reactions because there are no inactive internal atoms. Accordingly, SA cocatalysts are also an active research fields regarding photocatalytic hydrogen (H2) evolution which can be generated by abundant water and sunlight. Herein, it is investigated whether 10 transition metal elements can work as an SA on graphitic carbon nitride (g-C3N4; i.e., gCN), a promising visible-light-driven photocatalyst. A method is established to prepare SA-loaded gCN at high loadings (weight of ≈3 wt.% for Cu, Ni, Pd, Pt, Rh, and Ru) by modulating the photoreduction power. Regarding Au and Ag, SAs are formed with difficulty without aggregation because of the low binding energy between gCN and the SA. An evaluation of the photocatalytic H2-evolution activity of the prepared metal SA-loaded gCN reveals that Pd, Pt, and Rh SA-loaded gCN exhibits relatively high H2-evolution efficiency per SA. Transient absorption spectroscopy and electrochemical measurements reveal the following: i) Pd SA-loaded gCN exhibits a particularly suitable electronic structure for proton adsorption and ii) therefore they exhibit the highest H2-evolution efficiency per SA than other metal SA-loaded gCN. Finally, the 8.6 times higher H2-evolution rate per active site of Pd SA is achieved than that of Pd-nanoparticles cocatalyst. 相似文献