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排序方式: 共有1600条查询结果,搜索用时 15 毫秒
71.
Eun Young Park Yasushi Nakamura Kenji Sato Yasuki Matsumura 《Journal of the American Oil Chemists' Society》2012,89(3):477-484
We investigated the effects of amino acids and peptide on lipid oxidation in emulsion systems. For comparative purposes, we
also tested the antioxidant activity of ferulic acid, a typical phenolic antioxidant. Histidine and cysteine retarded lipid
oxidation (the amount of thiobarbituric acid [TBA]-reactive substances reached approximately 13 and 18 μM after 7 days, respectively),
whereas arginine, methionine, and tryptophan did not inhibit the progression of oxidation. Soy peptide also inhibited lipid
oxidation. Ferulic acid was found to be the most effective suppressor of lipid oxidation (TBA-reactive substances were suppressed
to <3 μM over 7 days). The antioxidant activities of soy peptide and ferulic acid were related to the purity of the emulsifier
used. The radical scavenging activities of soy peptide and ferulic acid were closely related to their inhibitory effects on
lipid oxidation. However, this was not the case for amino acids. Decreases in the turbidity of emulsions were closely related
to increases in TBA values. 相似文献
72.
Yinxiang Lu Altan Bolag Jun-ichi Nishida Yoshiro Yamashita 《Synthetic Metals》2010,160(17-18):1884-1891
2,2′-(1,4-Phenylene)bis(2,3-dihydro-1H-naphtho[1,8-de]-1,3,2-diazaboroine) [PND] and 2,2′-(4,4′-biphenylene)bis(2,3-dihydro-1H-naphtho[1,8-de]-1,3,2-diazaboroine) [BND] were synthesized and characterized by using differential scanning calorimetry (DSC) measurements, single crystal X-ray structure analysis, UV–vis absorption and electrochemical measurements, thin-film X-ray diffraction (XRD) and AFM studies. Organic field-effect transistors (OFETs) were fabricated by vacuum deposition with a bottom contact geometry using Au electrodes. Annealing treatment optimizes the organic active layer and increases the charge carrier mobility. Field-effect mobilities of 7.2 × 10?3 for PND and 4.1 × 10?4 cm2 V?1 s?1 for BND were found. 相似文献
73.
74.
A -conjugated polymer, poly(pyridine-2,5-diyl) (PPy) was investigated as a support for CuCl2 in the synthesis of dimethyl carbonate by oxidative carbonylation of methanol. The PPy–CuCl2 adduct had high catalytic activity which was comparable to that of the homogeneous CuCl2 catalyst. The adduct caused corrosion of stainless-steel vessels only to minor extent, compared with the homogeneous CuCl2 catalyst. This PPy–CuCl2 catalyst was easily recycled by filtration and showed a similar catalytic activity in the third time use. The presence of the -conjugated system in PPy, through which electrons can move, may bring about the high catalytic activity for the oxidative carbonylation of methanol, which involves Cu(II)/Cu(I) redox processes. 相似文献
75.
Satoshi lio Masakazu Watanabe Masaru Matsubara Yasushi Matsuo 《Journal of the American Ceramic Society》1989,72(10):1880-1884
The improvement of mechanical properties of Al2 O3 /SiC whisker composites has been studied with emphasis on the effects of the whisker content and of the hot-pressing temperature. Mechanical properties such as fracture toughness and fracture strength increased with increasing whisker content up to 40 wt%. In the case of the high SiC whisker content of 40 wt%, fracture toughness of the sample hot-pressed at 1900° decreased significantly, in spite of densification, compared with one hot-pressed at 1850°. Fracture toughness strongly depended on the microstructure, especially the distribution of SiC whiskers rather than the grain size of the Al2 O3 matrix. 相似文献
76.
Spherical-Impact Damage and Strength Degradation in Silicon Nitrides for Automobile Turbocharger Rotors 总被引:1,自引:0,他引:1
Yoshio Akimune Yasushi Katano Kazuo Matoba 《Journal of the American Ceramic Society》1989,72(8):1422-1428
Spherical-impact damage to two silicon nitrides is investigated. Gas-pressure-sintered silicon nitride exhibits an elastic response to impact by spherical partially stabilized zirconia particles, resulting in Hertzian cone-crack initiation in the sintered body. Pressureless-sintered silicon nitride, on the other hand, demonstrated an elastic/plastic response, with median/radical-crack initiation. These differences in behavior are due to their microstructural differences as well as to the different hardness values of the silicon nitrides in relation to those of the PSZ spheres. The postimpact bend strength of silicon nitrides is also degraded when crack length exceeds the inherent flaw size. 相似文献
77.
Sung-Sik Lee Mitsuhiro Nakamura Yasushi Takeuchi 《Korean Journal of Chemical Engineering》1989,6(2):81-87
Demulsification of stable oil-in-water emulsion was studied using powder adsorbent. Among various adsorbents tested, activated
carbon was found to be the most efficient regardless of the type of surfactants used. The more dose of activated carbon for
the demulsification was required, the higher concentration of the surfactant as well as the larger amount of oil and the bigger
size of the lipophilic and hydrophilic groups.
Empirical equations were obtained to correlate the dose of activated carbon to the residual concentration of oil as a function
of the initial concentration of surfactant. 相似文献
78.
Yasuhisa Maeda Yasushi Morinaga Yasumasa Tomita Kenkichiro Kobayashi 《Electrochimica acta》2009,54(6):1757-28
The iron oxide electrode was prepared from thermal oxidation of iron at 600 °C for 3 h in air atmosphere. This electrode with the structure of Fe3O4 and α-Fe2O3 showed the response of photoanodic current to the light with wavelength shorter than 600 nm. The band gap energy of this electrode was 1.99 eV. The onset potential of distinct steady photocurrent and also the flatband potential were 0.80 and 0.09 V vs. Ag/AgCl, respectively, in 0.1 M HNO3 aqueous solution. The cell consisting of the iron oxide photoanode in HNO3-Pb(NO3)2 and the graphite cathode in H2SO4-Ce(SO4)2 caused the PbO2 deposit on the surface of the former electrode due to visible light irradiation without application of voltage. By holding the potential of this electrode at more positive value than 0.90 V, the photoanodic removal rate of Pb2+ in HNO3-Pb(NO3)2 solution was higher than that observed when Ce4+ was used as electron acceptor. 相似文献
79.
Ryo Watanabe Yasushi Sekine Masahiko Matsukata Eiichi Kikuchi 《Catalysis Letters》2009,131(1-2):54-58
We investigated novel LaMnOx perovskite-oxide (ABO3) catalysts for effective catalytic dehydrogenation of ethylbenzene to produce styrene monomer. Comparison with industrial Fe–K catalyst, our La0.8Ba0.2Mn0.6Fe0.4O3-δ catalyst showed higher activity. Results show that the A-site in perovskite-type oxides affected catalytic dehydrogenation activities and that the B-site affected stability of the activities. 相似文献
80.