再生燃料电池的研究与应用

与传统二次电池（铅酸蓄电池、锂电池）相比，再生燃料电池在储能时间、能量密度、使用寿命和环境保护方面占有优势，可广泛应用于航天、军事领域和现场蓄能系统。本文介绍了再生燃料电池的原理、分类和应用情况，详细阐述了再生燃料电池双效电极和双效电极催化剂的制备方法以及水热管理的研究进展，指出再生燃料电池的不足之处并进行了展望。     

水、尿、血、发中钾、钠的火焰光度法测定

本法就其火焰的稳定性虽不如原子吸收分光光度法为佳,但方法迅速、准确,勿需昂贵设备。对试样中ppm级钾、钠的测定可以获得满意结果的。本文用火焰光度法试验了测定钾、钠的酸度,钙、镁等干扰元素及其消除。并用该法与电极法相对照,满意地测定了水、尿、血及发中钾、钠的含量。 1.仪器: (1)国产6400型火焰光度计;(2)国产DD-2B型电极电位仪;K离子选择性电极;pNa6801型玻璃电极;217型甘汞电极;232型甘汞电极。     

电解预浓缩技术在原子吸收分光光度分析中的应用

本文介绍了电解预浓缩技术的基本装置和各种工作电极材料,重点评述钨丝工作电极在火焰和无火焰原子吸收分析中的应用及其利弊,指出采用电解后的钨丝直接作原子化器可以弥补仪器设备的不足。最后表列出该技术在原子吸收分析中的应用现状。     

聚邻苯二胺膜电极中辣根过氧化物酶的电子传递

利用酸的电化学固定法制备含辣根过氧化物酶的聚邻苯二胺膜电极，研究其伏安行为及对Ｈ２Ｏ２还原的生物电催化作用，结果表明，在所述生物电催化反应中酶与聚合物基质 直接电子传递，但对新制的酶电极而言，电聚合时生成并包埋在酶膜中的寡聚体可作为电子传递体加速氧化态酶的再生，根据酶电极电流响应实验曲线的拟合，发现经态酶的再生速度随是极电位的变化表观上符合Ｔａｆｅｌ关系式，提出了酶反应学参数的测定方法。     

毛细管电泳和火焰光度检测器的联用研究

研究了毛细管电泳与火焰光度检测器的联用技术及其应用。有机磷农药经毛细管电泳分离后，流出液被引入气相色谱的火娄光度检测器进行特效检测，毛细管电泳的接地电极接口采用毛细管裂缝处裹醋酸纤维膜的方法，而毛细管电泳和火焰光度检测器的接口则借用了气相色谱的进样口。     

锂浆料电池基础科学问题研究

锂浆料电池是一种低成本、长寿命、高安全性和易回收的容量型电化学储能技术。与传统锂电池的固定粘接电极不同,锂浆料电池的储锂活性颗粒分布在浆料态的三维导电网络中,具有厚电极和可维护再生的特征。目前制约锂浆料电池应用的关键科学问题主要包括：解析不同浆料电极厚度和配比下电子-离子的混合导电机制,获得低内阻、高能量密度和功率密度的电极浆料;解析活性材料表面及浆料-集流体界面的电化学反应机制与微观结构演化规律,降低界面内阻,稳定界面特性,减少极化和容量损失;解析电池性能衰减及失效机制,优化电池在线维护与回收再生方法等。本文将从锂浆料电池的工作原理与特点、浆料电极的关键材料与混合导电机制、浆料-集流体界面与厚电极设计以及电极浆料的维护再生等方面对锂浆料电池基础关键科学问题的研究进展进行介绍。     

采用纳米金修饰的方法再生碳纤维微电极

采用电沉积法将纳米金(GNP)修饰到毒化的碳纤维电极表面制得再生碳纤维电极,用循环伏安法(CV)和差分脉冲伏安法(DPV)对神经递质在该再生电极上的电化学行为进行了研究。实验结果表明,在20 mmol/L,pH7.2的Tris-HCl缓冲溶液中,再生电极对多巴胺、去甲肾上腺素等神经递质具有良好的电化学响应。对纳米金的电沉积时间进行了优化,在优化条件下,采用DPV法,DA的氧化峰电流与其浓度在5×10~(-7)~1×10~(-4)mol/L范围内呈良好的线性关系,线性相关系数(R~2)为0.9979,检出限为5×10~(-7)mol/L。     

介体型酶电极二级催化反应速度常数的测定

采用开路驰豫法，测定了以二茂铁及其衍生物作为电子传递体的介体型酶电极的均相二级催化反应速度常数，结果表明二甲氨基甲基二茂铁，在绝氧条件下对于酶的再生反应具有高的催化活性，是一种性能优良的电子传递体．此外，讨论了开路弛豫法在酶电极研究中的适用条件及各种因素对该方法测定结果的影响．     

电解碘离子选择性电极(Ag/Agl电极)的性能试验

Herzdorf初步对比了电解Ag/AgI电极与AgI/Ag_2S固态膜电极,认为两者具有相似的分析性能。以后出现了用Ag/AgI电极测定氰离子的报告。我们测定了Ag/AgI电极的各项性能,确认该类电极具有一定的抗氧化能力,并作了初步应用,说明该电极性能良好,制作简单,容易再生,而且电极内阻极低,是一种廉价的离子选择性电极。 (一) 试剂与仪器     

分子印迹聚合物膜修饰电极的制备及在香草醛测量中的应用

以香草醛为模板分子,采用光引发聚合法和电化学聚合法分别在电极表面合成了香草醛印迹聚合物,探讨了两种方法的印迹、洗脱及电极再生机理。研究了香草醛在两种电极上的吸附行为,结果表明两种电极均可对香草醛进行吸附富集并进行线性扫描伏安法测定。两种电极均有很好的选择性、稳定性,且各有特点。     

Optimized carbon nanotube fiber microelectrodes as potential analytical tools

The preparation and interesting electrochemical properties of carbon nanotube (CNT) fiber microelectrodes are reported. By combining the advantages of CNT with those of fiber electrodes, this type of microelectrode differs from CNT-modified or CNT-containing composite electrodes, because they are made solely of CNT without other components, for example additives or binders. The performance of these electrodes has been characterized with regard to, among others, the electrocatalytic oxidation of analytes via dehydrogenase-mediated reactions. In this context the reversible regeneration of the coenzyme NAD(+) using a mediator is a key step in the development of new amperometric sensor devices and we have successfully immobilized mediator molecules that are very efficient for this purpose on the surface of the CNT fiber electrode. The microelectrodes thus obtained have been compared with classic carbon microelectrodes and have promising behavior in biosensing applications, especially after specific pretreatments such as CNT alignment inside the fiber or expansion of the specific surface by chemically induced swelling.     

一种新型低噪音碳纤维纳米电极

近年来,碳纤维超微电极在生命科学领域中已取得了广泛应用,电极的超微尺寸使之能对生物微环境进行实时监测^[1],还可作为微柱分离的检测 ^[2],自Adams研究组1976年开展微电极伏安法对细胞外液中生物胺以及有关代谢物的检测研究以来,碳纤维超微电极已成为探测脑内甚至单个细胞内神经递质的一种有力的工具,人们已对单个细胞内神经递质^[3]及激素^[4]的释放进行了探索性研究。     

Carbon nanofiber electrode array for electrochemical detection of dopamine using fast scan cyclic voltammetry

A carbon nanofiber (CNF) electrode array was integrated with the Wireless Instantaneous Neurotransmitter Concentration Sensor System (WINCS) for the detection of dopamine using fast scan cyclic voltammetry (FSCV). Dopamine detection performance by CNF arrays was comparable to that of traditional carbon fiber microelectrodes (CFMs), demonstrating that CNF arrays can be utilized as an alternative carbon electrode for neurochemical monitoring.     

Chitosan coated carbon fiber microelectrode for selective in vivo detection of neurotransmitters in live zebrafish embryos

We report the development of a chitosan modified carbon fiber microelectrode for in vivo detection of serotonin. We find that chitosan has the ability to reject physiological levels of ascorbic acid interferences and facilitate selective and sensitive detection of in vivo levels of serotonin, a common catecholamine neurotransmitter. Presence of chitosan on the microelectrode surface was investigated using scanning electron microscopy (SEM) and cyclic voltammetry (CV). The electrode was characterized using differential pulse voltammetry (DPV). A detection limit of 1.6 nM serotonin with a sensitivity of 5.12 nA/μM, a linear range from 2 to 100 nM and a reproducibility of 6.5% for n=6 electrodes were obtained. Chitosan modified microelectrodes selectively measure serotonin in presence of physiological levels of ascorbic acid. In vivo measurements were performed to measure concentration of serotonin in the live embryonic zebrafish intestine. The sensor quantifies in vivo intestinal levels of serotonin while successfully rejecting ascorbic acid interferences. We demonstrate that chitosan can be used as an effective coating to reject ascorbic acid interferences at carbon fiber microelectrodes, as an alternative to Nafion, and that chitosan modified microelectrodes are reliable tools for in vivo monitoring of changes in neurotransmitter levels.     

斜削碳纤维束微电极伏安法测定体液环境中的神经递质

报道斜削碳纤维束微电极的制备，活化预处理，伏安特性及微分常规脉冲伏安法测定多巴胺，肾上腺素和去甲肾上腺素的适宜条件。此法的检测灵敏度高，重现性好，抗维Ｃ干扰能力强。     

新型电流传感器-双拄碳纤维微电极

本文报道了双拄碳纤维微电极的研究及应用,分别用循环伏安法,计市电流法考察了该电极的性能,并用实验验证了双微电极的稳态电流理论公式,探讨了理论曲线与结果偏离的原因,采用发生一收集模式,提出间接测定维生素B~1的方法,并取得了满意的结果,维生素B~1的检测限为1.0×10^-^6mol.dm^-^3,线性范围为7.5 ×10^-^6-7.5×10^-^4mol.dm^-^3     

Pt Nanoparticle‐modified Carbon Fiber Microelectrode for Selective Electrochemical Sensing of Hydrogen Peroxide

We report a simple approach to the production of carbon fiber‐based amperometric microbiosensors for selective detection of hydrogen peroxide (H₂O₂), which was achieved by electrometallization of carbon fiber microelectrodes (CFMs) by electrodeposition of Pt nanoparticles. The Pt‐carbon hybrid sensing interface provided a sensitivity of 7711±587 μA ? mM^?1 ? cm^?2, a detection limit of 0.53±0.16 μM (S/N=3), a linear range of 0.8 μM–8.6 mM, and a response time of <2 sec. The morphologies of the Pt nanoparticle‐modified CFMs were characterized by scanning electron microscopy. To achieve selectivity, permseletive layers, polyphenylenediamine (PPD) and Nafion, were deposited resulting in exclusion of the anionic and cationic interferents, ascorbic acid and dopamine, respectively, at their physiologically relevant concentrations. The resultant sensors displayed a sensitivity to hydrogen peroxide of 1381±72 μA ? mM^?1 ? cm^?2, and a detection limit of 0.86±0.19 μM (S/N=3). This simple and rapid metallization method converts carbon fiber microelectrodes, which are readily accessible, to microscale Pt electrodes in 2 min, providing a platform for oxidase‐based amperometric biosensors with improved spatial resolution over more commonly used platinum electrode array microprobes.     

Synthesis and electrocoating of indole-thiophene comonomer on carbon fiber microelectrode, and surface topography by AFM

5,2-Thiophenylindole(5,2 In-Th) comonomer is synthesized by means of palladium catalyzed Stille cross-coupling reaction with an aim of obtaining extensively conjugated, low oxidation potential comonomer relative to its corresponding monomer. The comonomer is characterized by UV-Visible, FTIR, and NMR spectroscopic techniques, and the resulting conjugated copolymer exhibited the properties of both polyindole and polythiophene (having low oxidation potential and high conductivity).5,2 In-Th comonomer was electropolymerized onto carbon fiber microelectrodes. The copolymer was electrochemically coated (grafted) onto micron size carbon fiber by constant potential electrolysis and cyclic voltammetry (CV) and the resulting nanosize thin films of polymers were characterized using atomic force microscopy (AFM), and FTIR spectroscopy. The efficiency of the electrocopolymerization process on the carbon fiber surfaces under preparative constant current electrolysis and potentiodynamic conditions, was evaluated in order to ascertain the effects of copolymer thickness, dopant and morphology.     

Micro- and nano-electrodes for neurotransmitter monitoring

Chemical transmission between neurosecretory cells is a central biological phenomenon. Detecting neurotransmitter molecules released in the brain or in cell cultures is key to understanding how, when, and where chemical transmission occurs. Electrochemical techniques provide a unique quantitative approach to this field of research. Micro- and nano-electrodes can be engineered to be implanted in the living brain for interstitial fluid analysis, or placed close to, or even inside, isolated cells to detect exocytosis events and vesicles. Carbon fiber microelectrodes provide a common basis for detecting not only dopamine but also a wide variety of neurotransmitters ranging from biogenic amines, purines, and amino acids to free radicals and peptides. To achieve specific and sensitive in situ neurotransmitter detection, carbon fiber microelectrodes can be chemically modified with nanomaterials, enzymes, or aptamers or etched to reach nanoscale dimensions for intracellular analysis. Such micro- and nano-electrodes are an essential tool for analyzing living cells and tissues.     

Collisional electrochemistry of laser-ablated gold nanoparticles by electrocatalytic oxidation of glucose

We report the electrochemistry of gold nanoparticles (AuNPs), prepared by Laser Ablation Synthesis in Solution (LASiS), via the electrocatalytic oxidation of glucose upon single nanoparticle collisions at inert microelectrodes. Spherical AuNPs with diameters in the range 20–30 nm, as determined by transmission electron microscopy, were synthesized by LASiS of a gold plate immersed in water. Nanoparticle collisions were electrochemically detected through the AuNP-catalysed oxidation of glucose at carbon fiber microelectrodes in alkaline solution, enabling the electrocatalytic detection of single AuNPs. This approach provides a basis for detecting and understanding the electrocatalytic properties of pristine nanoparticles in aqueous solutions.