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111.
112.
The mixed complementarity problem (denote by MCP(F)) can be reformulated as the solution of a smooth system of equations. In the paper, based on a perturbed mid function, we propose a new smoothing function, which has an important property, not satisfied by many other smoothing function. The existence and continuity of a smooth path for solving the mixed complementarity problem with a P0 function are discussed. Then we presented a one-step smoothing Newton algorithm to solve the MCP with a P0 function. The global convergence of the proposed algorithm is verified under mild conditions. And by using the smooth and semismooth technique, the rate of convergence of the method is proved under some suitable assumptions. 相似文献
113.
A simple and controllable electrodeposition approach was established for one-step construction of novel reagentless biosensors by in situ formation of chitosan-carbon nanotubes-nile blue-horseradish peroxidase (CS-CNTs-NB-HRP) biocomposite film on electrode surface. The mediator effect of NB, conducting performance of CNTs and the biocompatible microenvironment of CS were combined by such one-step non-manual process. NB could interact with CNTs and resulted in good dispersion of CNTs-NB nanocomposites in aqueous solution. Cyclic voltammetry measurements demonstrated that electrons were efficiently shuttled between HRP and the electrode mediated by NB. The developed reagentless biosensor exhibited a fast amperometric response for the determination of H2O2 and 95% of the steady-state current was obtained within 2 s. The linear response of the reagentless biosensor for the determination of H2O2 ranged from 1.0 × 10−6 to 2.4 × 10−4 mol l−1 with a detection limit of 1.2 × 10−7 mol l−1. The biosensor exhibited high reproducibility and long-time storage stability. The as-prepared biosensor also showed effective anti-interference capability. The ease of the one-step non-manual technique and the promising feature of the biocomposite could serve as a versatile platform for fabricating electrochemical biosensors. 相似文献
114.
以电纺TiO2纳米纤维为基质, 柠檬酸为软模板, 采用一步水热法制备了具有三维立体网状结构的稀土Dy 3+掺杂YVO4/TiO2复合纤维. 通过X射线衍射、 扫描电子显微镜、 X射线光电子能谱、 N2吸附-脱附、 紫外-可见漫反射光谱及荧光光谱等手段对材料的组成、 表面形貌和性能进行表征, 以光分解水产氢实验考察其光催化活性. 结果表明, Dy 3+∶YVO4纳米枝与TiO2纳米纤维相互交联构筑的纳米纤维网具有大比表面积, 可提供更多活性位点, 改善了多相光催化反应的传递过程; 稀土Dy 3+掺杂的YVO4与TiO2复合形成异质结相互促进, 在拓宽光谱响应范围、 提高太阳光利用率的同时使光生电子-空穴对得到较好分离, 从而提高了样品的光催化活性. 模拟太阳光照射下, Dy 3+∶YVO4/TiO2复合纤维光催化产氢速率达到8.63 mmol· h -1·g -1, 是纯TiO2纳米纤维的10倍. 相似文献
115.
秸秆纤维素的一步快速提取和水解 总被引:4,自引:0,他引:4
研究了秸秆纤维素的一步快速提取方法, 在醋酸和硝酸溶液体系中, 选择10种不同的反应条件, 进行了提取条件优选, 然后对提取的纤维素样品分别进行了水解. 结果发现, 纤维素提取的最佳条件为120 ℃, 固液比为1∶25, 在体积分数为80%的醋酸和10%的硝酸混合溶液中反应20 min, 纤维素的产率为38%. 纤维素样品的水解实验发现, 在最佳条件下提取样品的葡萄糖含量都大于90%, 水解率达到94%. 13C NMR和FTIR分析结果表明, 纤维素的分子结构未被破坏, 但纤维素Ⅰβ含量较高, 木质素和半纤维素的去除率都很高, 表明此方法是比较理想的制备高纯度纤维素的方法. 相似文献
116.
Satoshi Yoda Katsuto Ohtake Yoshihiro Takebayashi Tsutomu Sugeta Takeshi Sako Tsugio Sato 《Journal of Sol-Gel Science and Technology》2000,19(1-3):719-723
The preparation of SiO2-TiO2 aerogels by supercritical impregnation of titanium alkoxides into silica alcogels was investigated. A mixture of CO2 and 2-propanol with dissolved titanium tetraisopropoxide modified with acetylacetone was used as the impregnation medium. Prior to the experiments, the supercritical behaviour of the impregnation solution was investigated. The microstructure and properties of aerogels prepared by the supercritical impregnation method were almost identical to those generated by the liquid impregnation. However, the time for impregnation was substantially decreased and the homogeneity of the impregnated titanium distribution on the aerogel increased. 相似文献
117.
118.
催化剂活性组分的负载方法对CVD法制备碳纳米管的影响 总被引:3,自引:0,他引:3
催化剂是影响CVD法制备碳纳米管的主要因素。本文报道了用配合浸渍法制备的催化剂在碳纳米管制备中的应用。XRD和TEM研究表明:与普通浸渍法制备的催化剂(B-Co/SiO2)相比,用配合浸渍法制备的催化剂(A-Co/SiO2)颗粒小,金属分散度高,生成碳纳米管的温度低。对于配合浸渍法制备的催化剂(A-Co/SiO2),低温(650-750℃)有利于生成直径小且管径均匀的碳纳米管;高温(800-900℃)容易生成直径大且层数多的碳纳米管或碳纳米棒。 相似文献
119.
Wei Ping HUANG Xiu Cheng ZHENG Shou Min ZHANG Xiao Hang QIU Wei WEI Bao Qing LI Shi Hua WU* Department of Chemistry NanKai University Tianjin 《中国化学快报》2001,(12)
Introduction Carbon monoxide is ubiquitous air pollutants emitted by many sources. Total oxidation of carbon monoxide to carbon dioxide is employed to meet environmental regulations in an economic way. Precious metals (Pt, Pd) are well-known oxidation catalysts with high activity and stability, and are widely used for exhaust gas emission control. However, the high cost of precious metals and their sensitivity to sulfur poisoning have long motivated the search for substitute catalysts. … 相似文献
120.
以正十二烷脱氢反应为探针反应,采用顺序浸渍、乙醇共浸渍、盐酸共浸渍的方法制备了Pt-Sn-K-Mg/γ-Al2O3催化剂,并采用NH3-TPD、CO脉冲吸附、H2-TPR、准原位XPS等表征手段探究浸渍顺序和溶剂对催化剂构效关系的影响。结果表明,盐酸水溶液共浸渍的方法制备的催化剂表现出了最佳的初始活性和较好的稳定性。催化剂的弱酸性位点的增加有利于Pt的分散,从而提高催化性能。采用乙醇为溶剂的共浸渍方法更有利于PtSn间形成更强的相互作用生成更多的PtSn合金,这对初始活性不利,但对选择性影响较小。 相似文献