全固态SiC参比电极的研制及应用

提出了一种全固态SiC参比电极制备方法.实验测试了该参比电极的稳定性、重现性、可逆性、响应时间、温度影响等因素.实验结果表明:该电极电位稳定在100 mV(vs.SCE)左右,响应时间30 s以内,具有重现性、可逆性好、使用寿命长、温度影响小等特点,可作为市售的饱和甘汞和Ag/AgCl参比电极的替代品使用.将该电极用于各种实际样品的测试中,结果令人满意.     

农药残留生物传感器薄层电极制作工艺研究

为了开发农药残留生物传感器的薄层电极,研究尝试采用重复银镜反应和阳极氧化法制作参比电极;以1×10^-4mol／L对硝基苯酚为测定液,采用时间-电势法对制作参比电极的工艺参数进行优化,确定Ag电极制作工艺是银镜反应次数9次、面积98mm^2,Ag/AgCl电极制作工艺是阳极氧化3min、面积70mm^2。采用循环伏安法对电极所做的检测结果表明：电极间差异小于5％,具有很好的一致性;Ag电极适用电压为-1．35—1．15V,Ag／AgCl电极适用电压为-1．45～1．0V。     

用铜—铝丝电极对电位滴定法测定磷酸根

用硝酸铅电位滴定法测定磷酸根时，以铜－铝丝电极对代替传统的铅ＩＳＥ－甘汞电极对作指示电极和参比电极，不但来源容易，使用方便，而且得到的电位突跃更大。     

简易型pH复合电极的研制

作者研制了无液接Ag/AgCl参比电极和简易型金属pH复合电极,并测试了它们的性能。该参比电极响应快,性能稳定。复合电极虽受氧化还原剂、络合剂干扰,但用于常见天然水、土壤及水果pH值的测定,结果仍然满意,用于酸碱自动电位滴定亦简便、快速,精密度高。     

WS-2005型pH计在污水监测中的应用

介绍了一种由金属锑电极 甘汞参比电极 温度电极组成三电极测量体系构成的污水pH值的工作原理、测量电路设计和参数计算方法及用此方法设计的工业pH计的特点,从而解决了常规玻璃电极仪表测量污水的pH值存在的缺点和不足。     

固态pH 探测电极的制备及其性能表征

我们采用熔融碳酸锂(LiCO3)氧化法制备了固态Ir／IrO2 pH电极，同时制备了改进型固态Ag／AgCl参比电极，并对它们的性能进行了表征。实验结果显示，在pH=0-14的溶液中，Ir／IrO2电极与参比电极电位差与pH值呈现良好的线性关系，直线斜率为-62．429mV／pH，截距为607．97mV，相关系数R2=0．993。温度对新型pH传感器响应信号的影响符合Nernst方程，易于进行温度校正。盐度对电信号强度的影响是线性的，在介质盐度已知，或向步测定介质盐度的前提下，可从响应电信号强度及盐度确定待测介质的pH值。     

介绍一种新型工业用电化学电极——固态参比电极

本文介绍了二机部五所研制的一种工业用电化学电极。该电极用于核原料加工处理工艺中效果良好,在化工、制碱、制药、造纸、冶金等工厂试用也证明其性能比甘汞电极更好。文中介绍了该固态参比电极的结构、特点、技术指标、应用及制作等。     

实验室小型发酵罐耐高温pH电极的研制

研究了实验室小型发酵罐耐高温复合pH电极的制作过程,对选材和Argenthal参比电极和pH电极接插件的研制作了详细讨论,介绍了pH电极性能测试方法。研制结果表明:该pH电极高温性能好,参比电极和指示电极电位稳定,电极响应时间快(<60s)、寿命长。     

固体参比电极的研制与应用

测量某一离子电极的电位时,要使用甘汞电极或银——氯化银作为参比电极,组成化学电池才能进行测量。测量时,由于电极内参比液和被研究体系溶液的组成不同,因而形成液接电势。液接电势的大小与构成液接界面的两种溶液性质密切相关,并受多种其他条件的影响,至今尚无法精确测量和计算。市场上的商品参比电极多以不同浓度的 KCl 溶液为内参比液,并经多孔烧结陶瓷与待测液相接。但对土壤和各种乳浊液(例如感光材料乳剂制备时的 pBr 或 pAg 的测量)用上述参比电极进行电化学测量时,由于介质是泥浆或混浊的悬浮体,则测量电极与它们接触     

电位滴定法测定KH_2PO_4中氯离子

本文报道采用银离子选择电极为指示电极,双液接饱和甘汞汞电极(外盐桥充注1MKNO_3)为参比电极,在酸性溶液中,直接用AgNO_3标准溶液滴定磷酸二氢钾成品或半成品中氯离子,以代替佛尔哈德法。该法滴定终点明显,电位突跃可达100毫伏左右,可     

Dynamic feedback regulation of the potential of a microfabricated liquid-junction Ag/AgCl reference electrode

A negative feedback mechanism to correct the deviation in the potential of a microfabricated Ag/AgCl electrode was developed using a nonstandard three-electrode system consisting of only thin-film Ag/AgCl electrodes. The reference electrode in the nonstandard three-electrode system was surrounded by a Ag/AgCl auxiliary electrode and provided a standard potential for other electrodes used for detection. With a constant potential applied to the Ag/AgCl working electrode with respect to the reference electrode, the shift of the reference electrode potential caused by a solution having different Cl⁻ concentration flowing in a neighboring flow channel polarized the working electrode slightly. Because of the nonpolarizable nature of Ag/AgCl, the slight shift of the potential of the working electrode caused a rapid current increase, resulting in the recovery of Cl⁻ concentration around the reference electrode. The effect of the feedback function was confirmed by comparing the results with those obtained from cases without the feedback function and from the potentiometric detection of Cl⁻ ions in a solution flowing in a flow channel.     

化学修饰GOD传感器

利用电化学修饰GOD工作电极及Ag/AgCl参考电极组装成了检测葡萄糖的GOD传感器．在0．7V的极化电位下，孩传感器对葡萄糖的响应电流小于1μA时，此电流与葡萄糖浓度成正比．传感器线性范围2．0×10-5至1．3×10-3mol／L，响应时间10s，稳定工作寿命150次，测量变异系数为2.73％。     

Composites: A novel alternative to construct solid state Ag/AgCl reference electrodes

An Ag/AgCl solid-state reference electrode is developed by means of a graphite–AgCl–Silver dag-epoxy resin composite. The response of the composite reference electrode (CRE) to chloride ions is evaluated; a linear non-nernstian response is observed associated to the following equation E = −15.15 (±1.10) − 44.05 (±0.38) log[Cl⁻]. Comparing the CRE's response potential versus a saturated commercial Ag/AgCl reference in KCl 0.1 M, a mean of 40.7 ± 0.4 mV of the distribution of potential versus time data is observed over a period of 1 h. The performance of the CRE as reference for a glass membrane electrode by means of direct pH measurements and quantitative determination of acids by acid–base titrations is evaluated obtaining statistically stable, precise and exact results compared with those obtained using a combined glass electrode. The typical cylindrical configuration of the CRE is changed to adapt it to a FIA system for the determination of ammonium ion, obtaining a sensitivity 50.30 ± 0.26 mV/log[NH₄⁺] and a linear range 8.5 × 10⁻⁵ to 0.1 M, which are analytical parameters statistically equivalent to those presented by the classical determination system.     

基于单针三电极的动态血糖传感器研制

研制了一种基于单根空心微针的新型植入式葡萄糖传感器,用于对人体血糖变化趋势进行连续监测.单根空心微针由结构相同的两个沿轴向磨去半边的不锈钢针管通过绝缘胶粘结而成,其分别作为传感器的工作电极与辅助电极;参比电极是置于该微针通孔之中的Ag/AgCl细丝;葡萄糖氧化酶( GOD)置于针尖的通孔处.测试结果表明:传感器的线性范围为3~22 mmol/L,灵敏度为1. 11μA/mmol/L,响应时间为10 s,且具有较好的抗干扰性.     

基于纳米金/碳纳米管修饰古墨电极测定大黄酸

本文首次采用自沉积方法将HAuCl4直接还原成纳米金颗粒并修饰在直接生长于石墨基体上的碳纳米管电极表面,制备了对大黄酸具有高催化性能的Au-CNTs／C电极。采用循环伏安法考察了大黄酸在Au—CNTs／C电极上的电化学行为,发现在-0．037V出现明显的氧化峰。在磷酸盐缓冲溶液P13S（DH=7．4）中,大黄酸的响应电流与浓度在1．8×10-4-2．5×10-3g／L范围内呈线性关系,相关系数为0．9878,其检测限为8．0×10^-4g／L。     

State-of-the-art monitoring of fuel acidity

Development of a novel iridium oxide (IrOx) based acidity sensor for off-line monitoring of fuel acidity is described. The sensor works in the potentiometric mode using an IrOx electrode as an indicating electrode and a Ag/AgCl or Ag/Ag₂O—reference electrode. The data show that the IrOx sensor responds to compounds present in fuel that have acid–base character. Using an off-line IrOx sensor, it is possible to determine the acidity of different fuels and discriminate between unstressed and thermally stressed fuels. It is possible to correlate the response of an IrOx sensor with the total acid numbers of different fuels. Experimental results also indicate that the low fuel conductance, the material used for sensor encapsulation, and/or the type of reference electrode may influence the response time of the IrOx sensor. Finally, the IrOx response has been demonstrated to be faster, better defined, more accurate and more reproducible than a glass electrode response for titrations of non-aqueous solutions.     

新型电化学CO气体传感器的研制

研制了一种用于测定CO的新型电化学式气体传感器,即把多壁碳纳米管自组装到铂微电极上,制备多壁碳纳米管粉末微电极,其电极在氧化过电位为+700mV时,对CO具有显著的电化学催化效应。以其电极为工作电极,Ag/AgCl为参比电极,Pt丝为对比电极,多孔聚四氟乙烯膜作为透气膜制成传感器。其传感器响应时间短、重复性好,能用于环境监测和控制。     

Electrochemical behavior of microfabricated thick-film electrodes

The possible chemical crosstalk between electrodes in microfabricated voltammetric oxygen sensors has been studied with an interdigitated electrode assembly. Experimental results show that significant amounts of hydrogen peroxide can be produced at the Au or Pt cathode and transferred to the surface of nearby counter and reference electrodes. Such chemical crosstalk may not only distort the sensing signal, but also affects the stability of the gold anode and the Ag/AgCl reference electrode.