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991.
Highly Dispersible and Bioavailable Curcumin but not Native Curcumin Induces Brown‐Like Adipocyte Formation in Mice
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992.
993.
Toshihiro Uehara Nobutaka YasudaMasayuki Okamoto Yoshitaka Baba 《Journal of power sources》2011,196(17):7251-7256
Metallic materials, especially Fe-Cr ferritic alloys, are promising as interconnect materials of solid oxide fuel cells (SOFCs) operated at around medium temperatures. ZMG232L is one of the developed Fe-Cr ferritic alloys for SOFC metallic interconnects.These metallic materials are usually machined or pressed into various shapes of interconnect parts, and thickness of these parts is often thin. However, the oxidation rate of thin sheet was much higher than that of thick one because Cr content decreased under oxide layer of edge part of thin sheet. Such accelerated oxidation behavior could be improved by reducing Mn, increasing Cr, and adding W in ZMG232L.It is also very important to reduce Cr-evaporation from the oxidized surface of ferritic alloys in cathode side. The aim of this study is to reduce the Cr-evaporation from oxidized alloy surface in air by coating with Mn-Co spinel oxide. In this study, oxidation behavior and Cr-evaporation of ZMG232L and improved Fe-Cr alloy, 232J3, coated with Mn-Co spinel oxide were investigated at elevated temperature in air. MnCo2O4 spinel coating on the pre-oxidized Fe-Cr ferritic alloy surface improved oxidation resistance and Cr-evaporation. 相似文献
994.
Keiji Komatsu Ayumu Toyama Tetsuo Sekiya Tomoyuki Shirai Atsushi Nakamura Ikumi Toda Shigeo Ohshio Hiroyuki Muramatsu Hidetoshi Saitoh 《Journal of Thermal Spray Technology》2017,26(1-2):195-202
In this study, yttrium oxide (Y2O3) films were synthesized from a metal-ethylenediaminetetraacetic (metal-EDTA) complex by employing a H2-O2 combustion flame. A rotation apparatus and various cooling agents (compressed air, liquid nitrogen, and atomized purified water) were used during the synthesis to control the thermal history during film deposition. An EDTA·Y·H complex was prepared and used as the staring material for the synthesis of Y2O3 films with a flame-spraying apparatus. Although thermally extreme environments were employed during the synthesis, all of the obtained Y2O3 films showed only a few cracks and minor peeling in their microstructures. For instance, the Y2O3 film synthesized using the rotation apparatus with water atomization units exhibited a porosity of 22.8%. The maximum film’s temperature after deposition was 453 °C owing to the high heat of evaporation of water. Cooling effects of substrate by various cooling units for solidification was dominated to heat of vaporization, not to unit’s temperatures. 相似文献
995.
D. Li N. Baba W. A. Brantley S. B. Alapati R. H. Heshmati G. S. Daehn 《Journal of materials science. Materials in medicine》2010,21(10):2723-2731
The goals of this study were to investigate the fatigue limits of two Pd–Ag alloys (Ivoclar Vivadent) with differing mechanical
properties and varying proportions of secondary alloying elements, examine the effect of casting porosity on fatigue behavior,
and determine the effect of casting size on microstructures and Vickers hardness. The alloys selected were: IPS d.SIGN 59
(59.2Pd–27.9Ag–8.2Sn–2.7In–1.3Zn); and IS 64 (59.9Pd–26.0Ag–7.0Sn–2.8Au–1.8 Ga–1.5In–1.0Pt). Tension test bars, heat-treated
to simulate dental porcelain application, were subjected to cyclic loading at 10 Hz, with R-ratio of −1 for amplitudes of
compressive and tensile stress. Two replicate specimens were tested at each stress amplitude. Fracture surfaces were examined
with a scanning electron microscope (SEM). Sectioned fatigue specimens and additional cast specimens simulating copings for
a maxillary central incisor restoration were also examined with the SEM, and Vickers hardness was measured using 1 kg load.
Casting porosity was evaluated in sectioned fatigue fracture specimens, using an image analysis program. The fatigue limit
(2 × 106 loading cycles) of IS 64 was approximately 0.20 of its 0.2% yield strength, while the fatigue limit of d.SIGN 59 was approximately
0.25 of its 0.2% yield strength. These relatively low ratios of fatigue limit to 0.2% yield strength are similar to those
found previously for high-palladium dental alloys, and are attributed to their complex microstructures and casting porosity.
Complex fatigue fracture surfaces with striations were observed for both alloys. Substantial further decrease in the number
of cycles for fatigue failure only occurred when the pore size and volume percentage became excessive. While the heat-treated
alloys had equiaxed grains with precipitates, the microstructural homogenization resulting from simulated porcelain firing
differed considerably for the coping and fatigue test specimens; the latter specimens had significantly higher values of Vickers
hardness. 相似文献
996.
To clarify the critical relative humidity (RH) to initiate pitting corrosion and the rusting mechanism in a marine atmospheric environment, pitting corrosion of Type 430 stainless steels under drops of MgCl2 solutions were investigated. A pitting corrosion test was performed at different relative humidities under droplets with various diameters and thicknesses. The probability of pitting decreased as the diameter and thickness decreased. Pitting progressed only when the chloride concentration exceeded 4 M, which is the equilibrium concentration at 80% RH. Accordingly, pitting of Type 430 could be initiated when the RH was less than 80%. Additionally, a pitting corrosion mechanism of Type 430 stainless steel under droplets containing chloride ions is proposed. 相似文献
997.
Maeda A Mizuno T Bunya M Sugihara S Nakayama D Tsunasawa S Hirota Y Sugihara A 《Journal of Bioscience and Bioengineering》2008,105(4):341-349
A novel cholesterol esterase with there and throughout to synthesisze steryl ester was obtained from the culture filtrate of a fungal strain Trichoderma sp. AS59 isolated from soil. The extracellular enzyme was a monomeric protein with a molecular mass of approximately 58 kDa and an isoelectric point of 4.3. The optimal temperature was between 35 degrees C and 40 degrees C, and the optimal pH was 7.0. The enzyme retained 75% of the initial activity after 18 h of incubation at 30 degrees C in the pH range of 3.5-7.5. Its relative hydrolytic activities on fatty acid cholesteryl esters were in the following order: butyrate (121%), linoleate (100%), caprylate (79%), myristate (42%), palmitate (38%), caproate (37%), and laurate (35%). Unlike mammalian pancreatic cholesterol esterase that is activated by primary cholates on hydrolysis of long-chain fatty acid cholesteryl esters, the enzyme from Trichoderma sp. AS59 displayed its basal activity and was not affected by cholate up to a concentration of 5 mM. At higher cholate concentrations the activity gradually decreased, but reincreased at about 40 mM to reach more than twice the basal activity at 100 mM. The enzyme exhibited a broad substrate specificity, being capable of hydrolyzing various fatty acid esters of not only cholesterol, but also methanol, glycerol, and p-nitrophenol. When incubated with a mixture of cholesterol and oleic acid of equal amounts, the enzyme achieved stoichiometrical esterification in 5 h, indicating its potential utility in food additives and liquid crystal devices. 相似文献
998.
Kurata A Fujita M Mowafy AM Kamachi H Kurihara T Esaki N 《Journal of Bioscience and Bioengineering》2008,105(4):429-431
(S)-2-Chloropropionate is a synthetic intermediate for phenoxypropionic acid herbicides. We constructed a system for asymmetric reduction of 2-chloroacrylate to produce (S)-2-chloropropionate with recombinant Escherichia coli cells producing 2-haloacrylate reductase from Burkholderia sp. WS and an NADPH regeneration system. The system provided 37.4 g/l (S)-2-chloropropionate in more than 99.9%e.e. 相似文献
999.
Keizo Kato Kazuki Yamashita Yasuo Ohdaira Akira Baba Kazunari Shinbo Futao Kaneko 《Thin solid films》2009,518(2):758-761
The attenuated total reflection (ATR) and emission light properties utilizing surface plasmon (SP) excitations were measured for the electrochemical change of poly(3-hexylthiophene-2,5diyl) (P3HT) thin films in-situ. The SP emission light could detect the SP excited by molecular luminescence of P3HT. The ATR and SP emission light properties were observed for the doped–dedoped states of P3HT thin film. The ATR and SP emission light properties were remarkably changed with the electrochemical doping and dedoping. The SP emission light also decreased by decrease of the molecular luminescence of P3HT by doping. For the dedoped-state P3HT thin film, SP emission light also increased by increase of the molecular luminescence. The SP emission light excited by molecular luminescence can be controlled by the control of doping–dedoping state. 相似文献
1000.
Crystal structure of homologous compounds, Zn3In2O6, Zn4In2O7, Zn5In2O8, Zn7In2O10, and In2O3 were refined by X-ray Rietveld analysis. Band structures of the homologous compounds were evaluated by first-principle calculation (Cambridge Serial Total Energy Package, CASTEP), using the structural data obtained from the Rietveld analysis. According to the results of CASTEP calculations, a sharp cut-off at the Fermi level could be observed when In3+ preferentially occupies the tetrahedral site (Zn3In2O6(4)) or the trigonal bipyramid site (Zn3In2O6(5)) in the (InZnk)Ok+1+ layers. The cut-off at the Fermi level could not be observed when In3+ and Zn2+ are totally disordered at these sites. Electronic structure calculation suggested that Zn3In2O6(4) is a good conductor and that Zn3In2O6(5) is a poor conductor. Results of geometry optimization indicate that the formation enthalpy of Zn3In2O6(4) was lower than that of Zn3In2O6(5). Considering the electronic structure and the formation enthalpy, Zn3In2O6(4) in which In3+ in the (InZnk)Ok+1+ layer occupies the tetrahedral site preferentially, is likely to be the favored structure. 相似文献