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31.
制备了一系列硼掺杂的还原氧化态石墨烯催化剂并应用于蒽加氢反应。结果表明,随着催化剂处理温度的升高,催化剂中有序碳结构会发生变化,硼会取代材料骨架中的碳,进而影响蒽和氢气的吸附活化。经硼改性后,催化剂对蒽加氢反应表现出了很高的加氢活性,蒽的最高转化率可达97%,深度加氢产物八氢蒽的最高选择性可达19%。  相似文献   
32.
石墨烯是最近发现的一种具有二维平面结构的碳纳米材料, 它的特殊单原子层结构使其具有许多独特的物理化学性质. 有关石墨烯的基础和应用研究已成为当前的前沿和热点课题之一. 本文仅就目前石墨烯的制备方法、功能化方法以及在化学领域中的应用作一综述, 重点阐述石墨烯应用于化学修饰电极、化学电源、催化剂和药物载体以及气体传感器等方面的研究进展, 并对石墨烯在相关领域的应用前景作了展望.  相似文献   
33.
《Electroanalysis》2006,18(23):2361-2368
The oxidation of benzophenone‐4 (2‐hydroxy‐4‐methoxybenzophenone‐5‐sulfonic acid) at glassy carbon electrode gives rise to stable redox active electropolymerized film during repetitive potential cycling between 0 to 1.3 V (Ag/AgCl). Cyclic voltammogram of poly(benzophenone‐4) film shows a redox couple with well‐defined peaks. The redox response of the modified electrode was found to be depending on the pH of the contacting solution. The peak potentials were shifted to a less positive region with increasing pH and the dependence of the peak potential was found to be 51 mV/pH. The electrocatalytic behavior of poly(benzophenone‐4) film modified electrode towards oxidation of dopamine, ascorbic acid and reduction of nitrite was investigated. The oxidation of dopamine and ascorbic acid occurred at less positive potential on poly(benzophenone‐4) film compared to bare glassy carbon electrode. For dopamine, the overpotential was reduced about 180 mV. Feasibility of utilizing poly(benzophenone‐4) film coated electrode in analytical estimation of dopamine, ascorbic acid and nitrite was also demonstrated.  相似文献   
34.
In previous works we have described a fully automated synthesis of new ferrocene labelled oligonucleotides (Fc-ODNs) probes with one or more electroactive markers at different position in the chain. These Fc-ODNs have shown good properties to detect ODN target in solution. Here we describe the post-functionalization of a conducting co-polymer based on ethylenedioxythiophene (EDOT) derivatives by a series of Fc-ODNs. The grafting of the Fc-ODNs probes resulted in the appearance of the ferrocene redox couple which directly confirm the effectiveness of the ODN anchoring compared to traditional approach based on IR spectroscopy and X-ray fluorescence of the films. Moreover, the electrochemical response of the modified electrodes analysed in organic media before and after hybridization with ODN target confirm that properties obtain in solution for Fc-ODNs already exist in the film. The changes in the current intensity were found to be dependant on the structure of the grafted ODN that validate our strategy to synthesize an optimal Fc-ODNs.  相似文献   
35.
采用循环伏安法研究了血红素与脑磷脂混合Y型LB(Langmuir-Blodgett)膜在玻碳电极上的电化学行为,结果表明血红素LB膜有良好的电化学活性,在0.1mol/L KCl溶液中有一对氧化还原峰(-0.42V/-0.30V);将血红素LB膜转移到玻碳电极表面得到的血红素LB膜修饰电极(heme LB-GC)对溶液中溶解氧的电化学还原有良好的催化作用,其催化还原过程具有不可逆电荷传递特性。  相似文献   
36.
The synthesis of two novel fluorescent uridine-2′-carbamate phosphoramidites is described. The reagents carrying fluorescent polyaromatic hydrocarbons 1-phenylethynylpyrene (PEPy) or 9,10-bis(phenylethynyl)anthracene (BPEA) are suitable for oligonucleotide synthesis. Prepared oligonucleotide conjugates show strong dye emissions at 401 and 485 nm, but low FRET rate when located in the oligonucleotide duplex. The dyes show considerable compensation of the usual carbamate duplex destabilization. The possible explanation of both effects is binding of PEPy and BPEA to the minor groove of the DNA duplex.  相似文献   
37.
Furans, thiazoles, fluorene or thiophene incorporated calix[4]pyrrole analogues were synthesized and characterized. The synthesis was achieved by utilization of various building blocks such as 7, 13, 14, 18 and 21. Acid catalyzed condensation of those building blocks with acetone or meso-disubstituted dipyrromethanes afforded desired macrocycles.  相似文献   
38.
石墨烯是最近发现的一种具有二维平面结构的碳纳米材料, 它的特殊单原子层结构使其具有许多独特的物理化学性质. 有关石墨烯的基础和应用研究已成为当前的前沿和热点课题之一. 本文仅就目前石墨烯的制备方法、功能化方法以及在化学领域中的应用作一综述, 重点阐述石墨烯应用于化学修饰电极、化学电源、催化剂和药物载体以及气体传感器等方面的研究进展, 并对石墨烯在相关领域的应用前景作了展望.  相似文献   
39.
Poly(malachite green) film modified Nafion‐coated glassy carbon electrodes have been prepared by potentiodynamic cycling in malachite green solution. The pH of polymerisation solution has only minor effect on film formation. Electrochemical quartz crystal microbalance (EQCM) was used to monitor the growth of the poly(malachite green) film. Cyclic voltammogram of the poly(malachite green) film shows a redox couple with well‐defined peaks. The redox response of the modified electrode was found to be depending on the pH of the contacting solution. The peak potentials were shifted to a less positive region with increasing pH and the dependence of the peak potential was found to be 56 mV per pH unit. The electrocatalytic behavior of poly(malachite green) film modified Nafion‐coated glassy carbon electrodes was tested towards oxidation of NADH, dopamine, and ascorbic acid. The oxidation of dopamine and ascorbic acid occurred at less positive potential on poly(malachite green) film compared to bare glassy carbon electrode. In the case of NADH, the overpotential was reduced substantially on modified electrode. Finally, the feasibility of utilizing poly(malachite green) film electrode in analytical estimation of ascorbic acid was demonstrated in flow injection analysis.  相似文献   
40.
聚吡咯水杨酸修饰电极的电化学行为及水杨酸含量测定   总被引:10,自引:0,他引:10  
李春光  崔刚 《分析化学》1994,22(9):922-924
本用电化学方法制备了聚吡咯-水杨酸修饰电极;并进行了电化学行为的研究,经电化学处理该是电极对水杨酸根具有选择性响应,响应线性范围在1.0×10^-^5-1.0×10^-^3mol/L之间。电极斜率为40mV/pC,该电极具有较好的稳定性,响应时间在180-300s之间;电极寿命可达60d。  相似文献   
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