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991.
Zn3V3O8 two-dimensional micro sheets are successfully synthesized by combination of solvothermal method and heat treatment. The Zn3V3O8 has better electrochemical performances after calcinations. 相似文献
992.
The synthesis of p-MPAQ and the electroanalytical chemical properties of the nickel(II)-p-MPAQ complex are reported in this paper. A sensitive adsorptive cathodic stripping procedure for trace nickel determination was developed. For a 3-min preconcentration time the detection limit is 3.0 × 10−11M. 相似文献
993.
Bixing Fang Lina Dong Xingwei Ding YingZi Ren Zhongsheng Lv Kuan Liu Feng Zhang Wei Zhang Jianjian Deng Hongbo Xin Xiaolei Wang 《中国化学快报》2019,30(6):1178-1181
Black fungus aerogel (BFA) exhibited interesting double-faced properties. Weexplored the diverse properties of each side of the black fungus in three aspects:water contact angle measurements, liquid selective absorption capacity and air pollutant adsorption abilities. 相似文献
994.
The successful realization of a stereospecific chloride degenerative transfer living Ziegler-Natta polymerization process that provides isotactic polyolefins of narrow polydispersity (Mw/Mn = 1.05) is documented. Variable-temperature NMR studies confirm the configurational stability of all species with respect to metal-centered epimerization and large magnitudes for both kbeta and k-beta. Additional kinetic analyses with an increasing concentration of the dormant state establish that kbeta is larger than k-beta. Finally, [Et3Si][B(C6F5)4] has been shown to be an effective substoichiometric halide abstractor for chloride degenerative transfer Ziegler-Natta polymerization. 相似文献
995.
A novel bis(beta-cyclodextrin) was synthesized, and its binding behavior with steroids was investigated to demonstrate that the cooperative co-inclusion of guest and tether by two cyclodextrin moieties is operative to afford the highest molecular selectivity of up to 3.6 for deoxycholate over taurocholate. 相似文献
996.
A simple and rapid capillary electrophoretic method was developed for the simultaneous determination of noradrenaline (NA) and dopamine (DA) in Portulaca oleracea L. The buffer solution used in this method was 40 mM tris (hydroxymethyl) aminomethane (Tris)-H3PO4 at pH 2.00 containing 15% methanol. The effects of pH value, organic modifier, and applied voltage were investigated. The linear ranges of NA and DA were 0.5-100 microg/mL (r=0.9952) and 6.25-200 microg/mL (r=0.9992), respectively. The relative standard deviations of the corrected peak area were 6.73% and 4.26%, respectively. NA and DA in Portulaca oleracea L. were simultaneous determined successfully within 5.6 min. In this way, the contents of NA and DA in different parts (stem, leaves, and seeds) of P. oleracea L. and in different extracts of leaves with different solvents (distilled water, 50% methanol, and methanol) were studied. 相似文献
997.
Youheng Shi Zhihui Zhang 《Journal of inclusion phenomena and macrocyclic chemistry》1994,18(2):137-147
The interactions ofp-tert.-butylcalix[4]arene bearing polyoxyethylene chains (C3) with pyrene (Py), 1-anilino-8-naphthalenesulfonate (ANS) andN-phenyl-naphthylamine (NPN) in aqueous solution were studied by absorption and fluorescence measurements. Absorption spectral changes and fluorescence enhancements reveal that C3, which has a hydrophobic cavity, can include organic molecules and ions in aqueous solution and form 11 host-guest complexes with ANS and NPN. C3 forms inclusion complexes with Py at different stoichiometries depending on the host: guest molar ratio. Binding constants of 2.2×104, 2.0×104 and 3.6×105 dm3 mol–1 were calculated for the C3Py, C3ANS and C3NPN complexes (11), respectively, based on the Benesi-Hildebrand equation.Author for correspondence. 相似文献
998.
999.
1000.
微量稀土对超导稳定化基体铜材的性能和组织的影响 总被引:4,自引:0,他引:4
研究了微量稀土元素对铜的机械性能、导电性和组织的影响,在铜中加入微量钇、钕、镝、铒和富铈混合稀土后,使铜的抗拉强度有所提高,并保持良好的塑性和导电性。 相似文献