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461.
采用溶胶-凝胶法结合超分子模板技术, 以四乙氧基硅烷(TEOS)和3-氨丙基三乙氧基硅烷(APTES)作为反应前体, 以十六烷基三甲基溴化铵(CTMAB)为超分子模板, 简单快速地制备了一种新型氨基硅胶整体柱, 通过氨基将金纳米粒子组装在整体柱材料孔表面并用于表面增强拉曼散射(SERS)光谱分析. 以对巯基苯胺(PATP)和结晶紫(CV)为拉曼探针, 考察了金纳米粒子修饰的氨基硅胶整体柱用作SERS活性基底的性能. 结果表明, 该整体柱基底具有良好的SERS增强效应, 可检测到的PATP和CV的最低浓度分别为10-9和10-11 mol/L. 与金溶胶SERS基底相比, 本文制备的整体柱基底的检测灵敏度显著提高, 并具有良好的信号均一性, 是一种具有现场痕量检测应用潜力的SERS活性基底. 相似文献
462.
以二乙烯三胺(DETA)为改性剂, 对多壁碳纳米管(MWCNTs) 进行共价键修饰,合成了一种对Au(Ⅲ)和Pd(Ⅱ)有选择性的吸附剂MWCNTs-DETA, 并对Au(Ⅲ)和Pd(Ⅱ)的吸附参数进行了研究和优化. 结果表明, 最佳洗脱剂浓度为1.0 mol/L 硫脲-1.0 mol/L 盐酸, Au(Ⅲ)和Pd(Ⅱ)的洗脱率分别为94.48%和89.06%, 最佳条件下Au(Ⅲ)和Pd(Ⅱ)的饱和吸附容量分别为50.45和25.68 mg/g. 在对吸附等温线的考察中, Au(Ⅲ)拟合Langmuir等温线较好, 而Pd(Ⅱ)则拟合Freundlich等温线较好. 吸附动力学均拟合二级模型较好. 相似文献
463.
Benbo Liu Bin Zhang Xumeng Wang Xuanying Chen Guangxin Gu 《Journal of Saudi Chemical Society》2019,23(7):856-863
A number of polyimide films incorporated with different amounts of octa(aminopropylsilsesquioxane) (POSS-NH2) were prepared from 1,2,4,5-Benzenetetracarboxylic anhydride, 4,4′-Oxydianiline and POSS-NH2. The structure and properties of the hybrid polyimide films were characterized and evaluated. It is found that, compared with pure polyimide without POSS-NH2, the thermal stabilities and electrical capabilities of hybrid polyimide films are improved. Meanwhile, the incorporation of POSS-NH2 also brings improvement in the flexibility of polyimide films. 相似文献
464.
(Bio)sensors based on manganese dioxide-modified carbon substrates: retrospections, further improvements and applications 总被引:1,自引:0,他引:1
Beyene NW Kotzian P Schachl K Alemu H Turkusić E Copra A Moderegger H Svancara I Vytras K Kalcher K 《Talanta》2004,64(5):1151-1159
An overview is presented which summarizes our accomplishment in the development of sensors and biosensors based on heterogenous carbon electrodes modified with manganese dioxide. Brief account of each sensor and biosensor has been given and example of real sample applications provided where appropriate. 相似文献
465.
本文研究了石墨表面的改进方法。实验结果表明,用聚乙烯的苯溶液对石墨探针或石墨管进行涂层处理,可以防止试液沿石墨表面的扩散与向石墨微孔中的渗透,从而使探针法或管壁法的分析结果得到改善。 相似文献
466.
Adsorption and electrochemical studies were carried out on three activated carbon samples first oxidized, then heat-treated under vacuum (at 180, 500 and 900 °C). The investigations were performed with aqueous electrolyte (Na2HPO4 and H3PO4) solutions containing selected nonpolar organics (benzene and n-hexane). Adsorption measurements were carried out on solution with a wide range of organics concentration (up to saturation point). Cyclovoltammetric curves of powdered electrodes prepared from the activated carbon samples were recorded for the organics in saturated solutions. The electric double layer capacities of the anodic and cathodic parts were estimated, and the surface anodic and cathodic charge was calculated both in absence and presence of organics in the electrochemical systems. The relative surface charge (in relation to systems without organics) was found to decrease with a reduction in the concentration of surface oxygen-containing groups. Other physicochemical parameters characterizing the degree of surface oxidation (total oxygen concentration, primary water adsorption centres) were also taken into consideration. The correlation between adsorption capacity towards the nonpolar organic compounds (obtained from adsorption isotherms) and change of surface charge was analyzed. 相似文献
467.
锂离子储能器件具有高能量密度与绿色环保等优点, 在未来新能源汽车和大规模储能领域中将显示出巨大的潜力. 然而, 由于传统锂离子负极材料如石墨、 硅存在电化学动力学缓慢与高倍率下的安全性等问题, 无法满足目前能源消费终端日益增长的快速充放电性能要求. 因此, 开发有利于锂离子快速嵌入/脱出、 安全性与稳定性优异的负极材料至关重要. 相比于传统的负极材料, 铌基氧化物具有合适的理论容量、 更安全的工作电位、 稳定且快速的离子传输通道等优点. 本文综述了高倍率铌基氧化物负极材料在锂离子储能器件领域的最新研究进展, 重点介绍了典型铌基氧化物的储锂机理与改性手段, 并对铌基氧化物负极材料未来的发展与挑战进行了展望. 相似文献
468.
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470.
Xin ChaiJingquan Liu Qing HeGuangbin Peng Chunsheng Yang 《Applied Surface Science》2011,257(24):10771-10774
A smooth, semitransparent and homogeneous Parylene C/nanosilica composite film was prepared by chemical vapor deposition (CVD). The film was deposited onto the Si substrate coated with a modified nanosilica layer. The nanosilica modified by silane coupling agent have uniform diameters and distribution in the film. The diameter can be roughly estimated in the range of 80-150 nm. The thermal stability of the composite film containing modified silica nanoparticles is better than that of the pure and doped film with commercial nanoparticles, which is ascribed to the strong chemical bonding between the modified nanosilica and Parylene monomers. σe and σs, as elastic limit and yield stress, are about 21.2 MPa and 23.4 MPa of the pure film, compared with 32.1 MPa and 33.4 MPa of the composite film due to the nanosize effect and intensive interface adhesion of silica nanoparticles as reinforcement. 相似文献