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排序方式: 共有308条查询结果,搜索用时 31 毫秒
71.
RhPt alloy catalysts were prepared in mesoporous silica using supercritical carbon dioxide in impregnation to achieve high dispersion with controlled morphology; catalytic activity and ethane selectivity are enhanced in butane hydrogenolysis. 相似文献
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73.
Taweecheep Pornchanok Naloka Kallayanee Matsutani Minenosuke Yakushi Toshiharu Matsushita Kazunobu Theeragool Gunjana 《Applied biochemistry and biotechnology》2019,189(1):144-159
Applied Biochemistry and Biotechnology - High temperature and high ethanol concentrations obviously affect vinegar fermentation. The thermotolerant and ethanol-resistant strains are expected to... 相似文献
74.
75.
Self-assembling properties of glycolipid biosurfactants and their potential applications 总被引:1,自引:0,他引:1
Dai Kitamoto Tomotake Morita Tokuma Fukuoka Masa-aki Konishi Tomohiro Imura 《Current Opinion in Colloid & Interface Science》2009,14(5):315-328
Biosurfactants (BS) produced by a variety of microorganisms show unique properties (e.g. mild production conditions, multi-functionality, higher environmental compatibility) compared to their chemical counterparts. The numerous advantages of BS have prompted applications not only in the food, cosmetic, and pharmaceutical industries but in environmental protection and energy-saving technology as well. Among BS, “Glycolipid type” BS are the most promising, due to high productivity from renewable resources and versatile interfacial and biochemical properties. Mannosylerythritol lipids (MELs), which are glycolipid BS produced by yeast strains of the genus Pseudozyma, not only exhibit excellent surface activities but also self-assemble to form different lyotropic liquid crystalline phases such as sponge (L3), bicontinuous cubic (V2) or lammellar (Lα). They also show induction of cell-differentiation against human leukemia cells, and high binding affinity towards lectins and immunoglobulins. Recently, the cationic liposome bearing MELs has been demonstrated to increase dramatically the efficiency of gene transfection into mammalian cells. These features of BS should broaden the applications in new advanced technologies. The current status of R&D on glycolipid BS, especially their functions and potential applications, is discussed. 相似文献
76.
M.M. Cavalcanti V.N. Domingos Cavalcanti R. Fukuoka J.A. Soriano 《Journal of Mathematical Analysis and Applications》2009,351(2):661-225
Let (M,g) be an n-dimensional (n?2) compact Riemannian manifold with or without boundary where g denotes a Riemannian metric of class C∞. This paper is concerned with the study of the wave equation on (M,g) with locally distributed damping, described by
77.
A concise total synthesis of xestodecalactone A, utilizing a Diels-Alder strategy is described. The focal Diels-Alder reaction relied on an "ynoate" dienophile to rapidly assemble the required resorcylinic acid scaffold. During this study, Diels-Alder cycloaddition reactions involving 1,3-disubstituted nonequivalent allene dienophiles were studied, and some surprising results were encountered. 相似文献
78.
Sachio Fukuoka Yasutaka Nakajima Wataru Watanabe Atsunori Mori Tatsuro Matsumura Kenji Takeshita 《Tetrahedron》2010,66(9):1721-6513
N,N,N′,N′-(Tetrakis-2-pyridylmethyl)ethylenediamine (TPEN) derivatives bearing the different number (1-4) of a double bond moiety on the pyridine ring are synthesized and subjected to copolymerization with N-isopropylacrylamide in the presence of AIBN. The obtained poly(TPEN-NIPA) gels show thermo-responsive swelling/shrinking behaviors and are employed for the extraction of cadmium(II) ion from the aqueous solution to examine the relationship of the gel characteristics and the extraction performance. The polymer gels composed of the TPEN derivative bearing three or four double bonds exhibit temperature-dependent change of swelling and shrinking in water. These gels extract CdII ion efficiently from the aqueous solution in the swelling state at 5 °C, while little extraction was observed at 45 °C with shrinking. 相似文献
79.
Catalytic conversion of cellulose into sugar alcohols 总被引:1,自引:0,他引:1
80.
A series of "organic chemical hydrides" such as cyclohexane, methylcyclohexane, cyclohexene, 2-propanol, and cyclohexanol were applied to the direct PEM fuel cell. High performances of the PEM fuel cell were achieved by using cyclohexane (OCV = 920 mV, PD(max) = 15 mW cm(-2)) and 2-propanol (OCV = 790 mV, PD(max) = 78 mW cm(-2)) as fuels without CO(2) emissions. The rates of fuel crossover for cyclohexane, 2-propanol, and methanol were estimated, and the rates of fuel permeation of cyclohexane and 2-propanol were lower than that of methanol. Water electrolysis and electro-reductive hydrogenation of acetone mediated by PEM were carried out and formation of 2-propanol in cathode side was observed. This system is the first example of a "rechargeable" direct fuel cell. 相似文献