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1.
《分析试验室》2021,40(7):797-802
选择了6种单双糖进行稳定性试验,最终选择以乳糖作为标准品,建立了CarboPac PA10为色谱柱,以250 mmol/L NaOH溶液等度淋洗,流速为1.0 mL/min的金电极的性能评价方法。通过与进口金电极进行对比,评测了自制金工作电极的性能。同时对薄层型安培池的检测响应公式进行验证,并探究了金电极的保存方法对检测灵敏度和结果的影响。结果表明:自行开发的金电极测样重复性良好,检测峰面积的RSD小于1.3%,背景和噪音较小,其性能优异且能长期稳定使用。  相似文献   

2.
硝酸盐含量的检测对于评价环境中硝酸盐污染和了解生态系统氮循环方面起着非常重要的作用。离子选择性电极因操作简单、选择性好、方便携带、价格低廉等优点被广泛应用于环境样品中硝酸根的测定。本文从离子选择性电极功能材料、电极设计和实际应用三方面阐述了近20年硝酸根离子选择性电极的研究进展,汇总了新合成硝酸根离子载体的选择性性能,从固体接触传导层和离子选择性敏感膜组分角度分析了固体接触式聚合物膜硝酸根离子选择性电极的构建机理,总结了非聚合物膜硝酸根离子选择性电极的发展,并对硝酸根离子选择性电极在环境中的典型应用进行了介绍,以期为水环境和土壤中硝酸根的测定提供技术支持。  相似文献   

3.
用循环伏安法研究了制备掺杂磷钼根离子聚吡咯化学修饰电极的条件,对其性能进行了电化学表征,电极对磷钼酸根(PMo12O^3-40)离子具有选择性电位响应,线性范围为1.0×10^-6~1.0×10^-3mol/L。斜率约为50mV,测定了电极的有关性能参数。电极可用于无机磷含量的检测。  相似文献   

4.
合成了磷钼类杂多酸,采用电化学方法首次在导电基体玻碳电极上研制了磷钼钒类杂多酸-聚吡咯薄膜修饰电极,该电极性能稳定,经久耐用,对膜修饰电极的电化学行为进行了表征,研究了膜修饰电极酸性水溶液中的氯酸根、溴酸根,、磺酸根,亚硝酸根,三阶铁离子,  相似文献   

5.
亚甲紫的电化学聚合和亚硝酸根的电催化还原   总被引:16,自引:0,他引:16  
运用循环伏安法在光谱纯石墨电极上制备了亚甲紫聚合修饰电极,在酸性,中性和碱性溶液中,亚甲紫单体均能在电极上进行电化学了和合得到性能稳定的亚甲紫聚合膜。研究了实验条件对膜生长过程的影响和亚甲紫聚合膜修饰电极的电化学行为,并讨论了该修饰电极对亚硝酸根的电催化还原作用。  相似文献   

6.
用循环伏安法(CV)制备了聚吡咯亚硝酸根离子选择性电极。表征了电极的性能。在10-1~5×10-5mol/L浓度范围内电极电位与亚硝酸根离子浓度成良好的线性关系,斜率51mV/PNO-2。观察了NO-2在PPy膜中掺杂-去掺杂过程,从而验证了电极响应是基于掺杂机理。  相似文献   

7.
一种新的硫酸根离子敏感电极   总被引:6,自引:0,他引:6  
探索新的材料制备离子敏感电极,研究这些电极的响应特性和响应机理,是离子电极研究的一个新方向['-".硫酸根离子敏感电极一直是离子电极研究中的一个难点·本文采用电沉积方法,在铜、钻、玻璃碳和低碳钢体表面沉积了Ni-P系非晶合金硫酸根离子敏感电极,电极对硫酸根离子在卫X10-'~IX10-'mol/L浓度范围内呈Nernst响应,检测下限可达4X10'mol/L,具有良好的重现性和稳定性.该硫酸根离子电极对常见阴离子具有良好的选择性,与迄今所报道的SO广离子敏感电极比较显示了较优异的特性.1实验部分将金属铜(99%,4-5mm)、金属钻…  相似文献   

8.
一种新的磷酸根离子敏感电极研究   总被引:5,自引:0,他引:5  
一种新的磷酸根离子敏感电极研究肖丹,俞汝勤,李军,袁孔铨(湖南大学化学化工系,长沙,410082)关键词磷酸根,离子选择电极,磷酸二氢根磷酸根离子浓度的测定在化学化工、环境保护、生命科学和临床医学等领域有着重要的意义。对磷酸根离子敏感电极的研究和探索...  相似文献   

9.
复合高分子膜修饰电极直接测定大脑内源性神经递质   总被引:4,自引:0,他引:4  
采用阳离子交换剂Nafion和醋酸纤维素复合修饰的碳纤维电极具有电荷选择性和尺雨选择性,对复杂样品具有独特的选择和抗干扰性,在动物活性伏安分析中,该复合修饰电极成功地抑制了神经递质代谢产物,抗坏血酸和尿酸等电化学活性物质在电极表面的反应,直接检测了脑内神经质多巴胺的氧化电流,该电极采用静电浸浦法多次涂布,使电极的复合膜牢固,并具有很好的分析性能,同时,对复合修饰电极的作用机理进行了探讨。  相似文献   

10.
全固态锂离子选择性电极研究   总被引:1,自引:0,他引:1  
研究了新型载体HPMBP-TOPO体系几种全固态锂离子选择性电极(涂丝电极、单层全固态电极、聚吡咯修饰层内接触电极)的性能。与传统型电极相比,固态电极响应斜率有所降低,而选择性稍有提高。其中聚吡咯修饰层内接触电极性能为最佳,该电极响应斜率为56.7mV/decade,并具有良好再现性和长期稳定性。  相似文献   

11.
Kang TF  Shen GL  Yu RQ 《Talanta》1996,43(11):2007-2013
The permselectivity of neurotransmitters such as dopamine, epinephrine, and norepinephrine at overoxidized polypyrrole (OPPY)-film-coated glassy carbon electrodes has been investigated. The chemically-modified electrodes exhibit attractive permselectivity and antifouling properties of rejecting anionic species, e.g. ascorbate, etc. Compared with the response of neurotransmitters at modified electrodes overoxidized in phosphate buffer solution (pH 7.4), higher sensitivity and reversibility response can be obtained at modified electrodes overoxidized in sodium hydroxide solution. The effect of film thickness on the permselective response was tested. Rotating disk electrode experiments were used to determine the apparent diffusion coefficients of several electroactive solutes in the OPPY films. The influence of the hydrophobicity of the organic ions on the permeability within the polymer films was discussed. Dopamine and epinephrine were determined at the 1 x 10(-6)-1 x 10(-4) M level by means of voltammetry after an exposure period of 2 min in 0.1 M phosphate buffer (pH 7.4) with detection limits of 8 x 10(-7) M and 6 x 10(-7) M respectively.  相似文献   

12.
综述了近年来农业、环境科学和食品科学中NO_3~-、NO_2~-同时测定方法的研究进展。  相似文献   

13.
The modification of carbon powder with manganese dioxide using a wet impregnation procedure with electrochemical characterisation of the modified powder is described. The process involves saturation of the carbon powder with manganese(II) nitrate followed by thermal treatment at ca. 773 K leading to formation of manganese(IV) oxide on the surface of the carbon powder. The construction of composite electrodes based on manganese dioxide modified carbon powder and epoxy resin is also described, including optimisation of the percentage of the modified carbon powder. Composite electrodes showed attractive performances for electroanalytical applications, proving to be suitable for the electrochemical detection of hydrogen peroxide, ascorbic acid and nitrite ions with limits of detection comparable to the detection limits achieved by other analytical techniques. The results obtained for detection of these analytes, together with composite electrodes flexible design and low cost offers potential application of composite electrodes in biosensors.  相似文献   

14.
New zeolite-modified carbon-based electrodes are described. They are based either on the physical anchoring of zeolite particles on the surface of solid carbon paste (the viscosity of which can be tuned by temperature change or controlled dissolution by an organic solvent), or on the dispersion of zeolite particles in the bulk of a carbon paste matrix containing solid paraffin as a binder. Both these systems display superior electrochemical performance in comparison to corresponding "classical" zeolite-modified carbon paste electrodes using mineral oil as binder. These well-described composites usually suffer from poor mechanical stability in stirred media as well as memory effects due to significant ingress of the external solution into the bulk electrode. Advantages of the zeolite-modified solid carbon paste electrodes are reported mostly on the basis of two electroanalytical applications: the voltammetric detection of Cu2+ ions after accumulation by ion exchange at open circuit, and the indirect amperometric detection of non-electroactive species (i.e. Na+) in flow injection analysis.  相似文献   

15.
The present study serves to focus attention on the modification of multiwalled carbon nanotube with 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) and its application for the development of a new, simple, and selective modified electrode in order to determine Pb(II) in standard alloys and water samples. The electrochemical method was based on open circuit accumulation of lead ions onto a 5-Br-PADAP-modified multiwalled carbon nanotube electrode and then their anodic stripping voltammetric determination. The linear range for Pb(II) ions was from 0.9 to 114.6???g?L?1. The detection limit and relative standard deviation were found to be 0.1???g?L?1 and 1.6%, respectively. This method demonstrates the powerful application of carbon nanotubes in the field of mercury-free electrodes in voltammetric stripping analysis.  相似文献   

16.
用抑制型离子色谱法定量测定了NO2-和NO3-.两种阴离子在最佳色谱条件下,8 m in内达到基线分离.对于NO2-,检出限为0.002 mg/L,相对标准偏差为2.58%,线性范围0.2 mg/L~20 mg/L,相关系数0.999 6.对于NO3-,检出限为0.011 mg/L,相对标准偏差为2.01%,线性范围0.3 mg/L~30 mg/L,相关系数0.999 2.该法用于蔬菜中NO2-和NO3-的测定,结果良好.  相似文献   

17.

The present study serves to focus attention on the modification of multiwalled carbon nanotube with 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) and its application for the development of a new, simple, and selective modified electrode in order to determine Pb(II) in standard alloys and water samples. The electrochemical method was based on open circuit accumulation of lead ions onto a 5-Br-PADAP-modified multiwalled carbon nanotube electrode and then their anodic stripping voltammetric determination. The linear range for Pb(II) ions was from 0.9 to 114.6 μg L−1. The detection limit and relative standard deviation were found to be 0.1 μg L−1 and 1.6%, respectively. This method demonstrates the powerful application of carbon nanotubes in the field of mercury-free electrodes in voltammetric stripping analysis.

  相似文献   

18.
本文报道了一些新的长碳链季铵化合物的制备,应用这些化合物制得了I~-,NO_3~-,ClO_4~-,IO_4~-,SCN~-,N_3~-,WO_4~-等无机阴离子选择电极;BF_4~-、TaF_6~-、NbF_7~-、CrO_3F~-等络合阴离子电极以及苦味酸根、烷(芳)基磺酸根(阴离子洗涤剂)电极、磺原酸根、水杨酸根、糖精、安乃近等药物及其它有机分子的电极。还讨论了它们在阴离子选择电极中的结构效应。其中有些电极已经作为商品生产,并广泛应用于各种分析领域。  相似文献   

19.
Applicability of square wave voltammetry for the determination of Cu(II) ions by PolyLut/GC and PolyKae/GC electrodes was evaluated in this study. For this luteolin and kaempferol were electrochemically polymerized on glassy carbon (GC) electrode surface in order to get polyluteolin and polykaempferol-modified glassy carbon electrodes (PolyLut/GC and PolyKae/GC, correspondingly). The formation of polyphenol layer on the GC electrode surface was evidenced by atomic force microscopy. Square wave voltammetry was found to be more sensitive in comparison with differential pulse voltammetry. It was determined that PolyLut/GC and PolyKae/GC electrodes offered great sensitivity towards Cu(II) ions with very low limit of detection, good reproducibility, sufficient stability and excellent selectivity of analytical signal.  相似文献   

20.
化妆品中阴阳离子的快速测定及其用于化妆品鉴别的研究   总被引:3,自引:0,他引:3  
用离子色谱电导检测器对黑泥类化妆品中的阴、阳离子(Na+,NH+4,K+,Mg 2+ ,Ca 2+ ,Cl-,Br-,NO-2,NO-3和SO 2- 4)进行了测定。阳离子分离条件: 阳离子交换柱ICS C25,均苯四甲酸淋洗液浓度2.0 mmol/L ,流速0.6 mL/min ;阴离子分离条件: 阴离子交换柱Shim pack IC A1,淋洗液为2.5 mmol/L 邻苯二甲酸和2.4 mmol/L 三羟基氨基甲烷,流速1.0 mL/min 。结果表明,上述10种离子在较宽浓度范围内有良好  相似文献   

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