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81.
82.
Highly concentrated, well-stable gold colloids can be prepared directly from an amine-bearing polyelectrolyte-HAuCl4 aqueous solution at room temperature. It is found that increasing molar ratio of polyelectrolyte to gold leads to increasing particle size. UV-vis spectra, transmission electron microscopy (TEM), and X-ray photoelectron spectra (XPS) were used to characterize the products thus formed. 相似文献
83.
[structure: see text] Platinum(II) terpyridyl acetylide complex (1) was incorporated into Nafion membranes as a photosensitizer, and the Nafion was immersed in an aqueous or organic solution of 7-dehydrocholesterol, alpha-pinene, or cyclopentadiene. This photosensitizer system can generate singlet oxygen ((1)O(2)) in high quantum yield to oxidize the alkenes in the solution outside the Nafion and can be easily removed from the reaction vessel at the end of the photooxidation. 相似文献
84.
本文报道了一类新型全硫冠醚聚合物的合成,即由聚环硫氯丙烷与二巯基化合物反应,生成具有冠醚环结构单元的交联型聚合物。并研究了这些聚合物的对金属离子的络合性能。 相似文献
85.
86.
The new electrical and optical properties of nanomaterials depend sensitively on both size and shape, which are of both fundamental and technological interest. This paper introduces a simple chemical method to produce copper particles, which has the ability to shape the particle without using any capping agent or template. In our synthetic procedure, the reactant concentration and temperature exerted a strong influence on the shape of the copper particles. At low reactant concentrations, the particles were cubic; at high reactant concentrations, obtained particles were spherical. The number of hollow particles greatly increased when the synthesis was performed at low temperature. We also synthesized a copper cubic ring at lower temperature, and it has been rarely reported. The absorption spectrum of hollow particles showed obvious red shifts, which suggests the possible assembly of novel optical materials. 相似文献
87.
88.
研究了半导体隔片光电化学电池(SC-SEP)中光池溶液的pH、暗池溶液的氧化还原电对以及两池中的暗电极对电池的开路电压、光生电压、短路光电流和光伏安特性的影响。对它们的影响机制进行了初步分析。通过合理选择电池体系,SC-SEP的性能可比单隔室的光电化学电池(PEC)优越。 相似文献
89.
IntroductionSupportedPt-Sncatalystsareimpo~inthepdrileumandpthechendcalindustricsbecauseoftheirsuperiorcatalyticperformances.Forexample,Pt-Snsupportedonaneutralsupporthasbeenreportedtoexhibithighdehydrogenationselectivityanddebilitythansupportedplatinumca… 相似文献
90.
Lee KB Kim DJ Lee ZW Woo SI Choi IS 《Langmuir : the ACS journal of surfaces and colloids》2004,20(7):2531-2535
The micropatterns of biological ligands (biotin and RGD peptides) were generated on a flat surface of biodegradable polymer, poly(glycolic acid) (PGA). The immobilization of biological ligands onto the surface of biodegradable polymers (especially aliphatic polyesters) is usually hampered by the absence of functionalizable groups on the polymer backbone. We demonstrate herein that PGA polymer films were modified by surface hydrolysis to introduce carboxylic acid groups on the film surfaces, which were subsequently used for patterning amine-terminated ligands by microcontact printing. Fluorescence microscopy was used to verify the pattern of biotin on the surface of the PGA films after complexation with fluorescein-conjugated streptavidin. In addition, the cellular micropatterns were obtained from micropatterns of RGD peptides on the surface-hydrolyzed PGA films. 相似文献