共查询到19条相似文献,搜索用时 46 毫秒
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近年来,生物传感器逐渐普及到各领域,如食品检测、生物医疗、化学分析等。随着纳米技术领域的快速发展,通过将各种纳米技术应用到电化学酶传感器,促进电化学酶传感器向全新方向发展。目前,纳米材料具有表面效应、小尺寸效应、量子尺寸效应等特征,与其他材料相比较,其具有光、磁、电等突出表现。在生物传感器方面,要求电极材料具有良好的导电性和相容性,能同步负载大量的生物酶分子,提高生物酶分子与电极间的传递效率,缩短效应时间,提高传感器的灵敏度,从而实现传感器性能最佳化。 相似文献
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超高灵敏度和特异性的电化学生物传感器在环境风险物质监测以及生物医学检测领域具有重要意义,而构建生物亲和性高、制备工艺简单、成本低廉的检查电极是电化学生物传感器走向应用的关键。本文采用3D打印技术制备出重复性良好的三维石墨烯复合电极,然后通过电化学氧化的方法调控表面石墨烯的形貌和氧化基团。所制备的电化学生物传感器在环境污染物微囊藻毒素(MC-LR)的检测中展现出超高的灵敏度,其线性检测区在4×10-6~1 μg/L,检测限为1.5×10-7 μg/L。同时,通过改变适配体检测探针后,该电化学生物传感器对于多巴胺、重金属Hg2+、四环素等均具有极高的检测灵敏度。本研究为电化学适配体生物传感器走向应用化提供了一种新的思路,为开发超高灵敏度环境监测和生物医学检测传感器提供一定的基础数据。 相似文献
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基于铅离子脱氧核酶对铅离子的特异性识别作用,研制了用于测定铅离子的高灵敏电化学生物传感器。该传感器以固定于电极表面、末端标记了电信号基团的脱氧核酶作为识别元素和信号探针。当传感界面与含有铅离子的溶液接触时,脱氧核酶的酶链在铅离子的辅助作用下将修饰了电信号基团的底物链切断并使其脱离电极表面,从而使电极表面电信号分子的电流减小,产生用于铅离子定量检测的电信号。在0.5~12.5μg/L的浓度范围内,检测信号与Pb~(2+)浓度呈良好的线性关系,Pb~(2+)的检出限为0.3μg/L。同时,该电化学生物传感器对Pb~(2+)的检测表现出良好的特异性和选择性。 相似文献
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以莲藕为生物质原料、聚磷酸铵(APP)为氮磷掺杂剂制备了一种N、P共掺杂生物质碳材料,采用SEM、TGA、XRD、XPS和FTIR对材料的结构、形貌和元素组成进行了表征,并以该碳材料修饰玻碳电极,构建了一种检测芦丁的电化学传感器。采用电化学阻抗谱、循环伏安法和差分脉冲伏安法考察了传感器的电化学性能及芦丁在不同电极上的电化学行为。结果表明,在莲藕与APP质量比为1∶1、热解温度为800℃条件下,制备的热解碳材料修饰电极对芦丁的检测效果最好。在最优化条件下,芦丁浓度与该修饰电极的响应电流呈线性关系,检出范围为0.01~10μmol/L,检出限为1.19×10–2μmol/L(信噪比=3)。此外,该修饰电极对双黄连口服液和健康人尿样中芦丁的测定效果良好。 相似文献
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无酶葡萄糖电化学传感器的研制是近年来的一个研究热点。研究无酶葡萄糖电化学传感器的关键是开发合适的电极修饰材料以提高传感器的性能(如响应时间、线性范围、灵敏度、选择性等)。文章简要的综述了国内的研究论文中的无酶葡萄糖电化学传感器,并对可能的研究趋势做了展望。 相似文献
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The objective of this work is to evaluate the use of an electrochemical hydrogen pump for recirculation of hydrogen in a fuel
cell stack. The hydrogen pump needed about 130 mV at 0.5 A cm−2, primarily because of the cell resistance (0.18 Ω cm2). This voltage loss was higher than a fuel cell voltage gain resulting from hydrogen recirculation. However, if one pumping
cell is used for 10 active cells this means 13 mV loss per cell (or about 2%) which may be an acceptable voltage penalty.
A stack with hydrogen recirculation should operate with less voltage fluctuation and should need purging less often than a
stack operating with a dead-end mode of hydrogen supply. An additional benefit of hydrogen purification may be achieved in
the systems with a fuel processor where operation in a dead-end mode is not possible. Attention must be paid to water management
when designing and operating a hydrogen pump within a fuel cell stack. 相似文献
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电解加工是一种以离子形式去除加工件表面材料的方式,使得该技术在微细加工领域具有先天的优势。各种新型电解加工方式的出现,解决了传统电解加工中的不足,在机械、电子、宇航等领域得到广泛应用。 相似文献
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N-甲基羟胺及其盐酸盐广泛应用于医药和农药中间体的合成,以及核废料处理与回收等领域.采用线性扫描和循环伏安方法,研究了硝基甲烷电还原一步制备N-甲基羟胺及其盐酸盐的反应特性.在盐酸溶液中,硝基甲烷在铜、铜汞齐和镍电极上均具有明显的还原活性,其活性大小依次为铜>铜汞齐>镍>石墨,其中硝基甲烷在铜电极上的还原电位为-0.65~-0.75V(vs.SCE).电解合成试验结果表明,采用铜和铜汞齐作为阴极材料,电合成N-甲基羟胺盐酸盐的电流效率均超过90%,产品收率超过86%;采用镍和石墨作阴极,电流效率和产品收率均较低.其中铜电极在1200~2500A·m-2的电流密度范围内,电解时间为理论电解时间的80%时,具有最好的电流效率.与传统的催化氢化法合成N-甲基羟胺比较,电化学还原硝基甲烷制备N-甲基羟胺盐反应条件温和、污染少、成本低,是一种非常有效的合成新方法. 相似文献
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Combined electrooxidation and assisted electrochemical coagulation of aqueous phenol wastes 总被引:1,自引:0,他引:1
P. Cañizares F. Martínez J. García-Gómez C. Sáez M.A. Rodrigo 《Journal of Applied Electrochemistry》2002,32(11):1241-1246
The electrochemical treatment of basic (pH 12) aqueous phenol wastes using stainless steel electrodes is described. Two different processes have been identified in the removal of the phenol from aqueous wastes: electrooxidation, which leads to the formation of carboxylic acids and carbon dioxide, and solids-forming assisted electrochemical processes (including complexation, precipitation and/or coagulation) produced by the generation of Fe3+ ions in the waste during treatment. The effect of the initial carbon concentration, temperature and current density has also been investigated. It was determined that increases in the initial carbon concentration and temperature lead to increases in the reaction rates of the treatment processes and that increased current density leads to a decrease in the rate of electrooxidation and an increase in the rate of the solid-forming processes. 相似文献
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K. Scott 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1992,54(3):257-266
This paper presents a relatively straightforward approach to the modelling of electrochemical reactors operated in batch or continuous modes. The models are based on ideal flow assumptions of either well-mixed or plug flow and incorporate reaction rate models based on electrochemical kinetics and mass transport at one electrode. General characteristics of the reactor models are described, particularly with regard to the need for good mass transport in metal recovery applications. An example is given on the use of the model in the recovery of a heavy metal (Cd2+) from an acidified solution containing Cd(II) and Fe(III) ions. The reaction rate model is based on experimental data. 相似文献
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Bahadir K Krbaht Bekir Salih Abdurrahman Tanyola 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2002,77(1):70-76
The electrochemical conversion of highly concentrated synthetic phenolic wastewater was studied on carbon electrodes in a batch electrochemical reactor. The effects of reaction temperature, electrolyte concentration, current density and initial phenol concentration on phenol conversion were elucidated. The wastewater was synthetically prepared and used in reactions carried out generally at 25 °C with an initial phenol concentration of 3500 mg dm?3. Although current density increased, phenol conversion% and initial phenol conversion rate did not increase correspondingly above 35 °C and an electrolyte concentration of 90 g dm?3. As the voltage values applied were increased, the increasing current density resulted in fast phenol conversion. Kinetic investigations denoted that overall phenol destruction kinetics was of zero order with an activation energy of 10.9 kJ mol?1. Under appropriate conditions, phenol was completely converted within 15 min for an initial phenol concentration of 98 mg dm?3 while 8 h was required to gain 95% conversion using 4698 mg dm?3. Solid polymeric materials were produced at initial phenol concentrations above 500 mg dm?3 using the appropriate current density. In the reaction medium, only mono‐, di‐ and tri‐substituted chlorophenols were formed and 100% of all species were either oxidised or contributed to the formation of a polymeric structure. Almost all of the phenol loaded to the reactor was converted into non‐passivating polymeric products, denoting a safe and easy method for the separation of phenol. © 2001 Society of Chemical Industry 相似文献