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1.
采用亚硝基五氰合铁酸铁(FePCNF)粉末与碳粉质量比为2∶3混合,制备了FePCNF修饰碳糊电极.研究了FePCNF修饰碳糊电极在KNO3溶液中的电化学行为和扫速、pH值及不同支持电解质的影响.该电极可用于催化氧化检测葡萄糖.实验表明:FePCNF修饰碳糊电极在0.5 mol/L KNO3溶液中有一对灵敏的氧化还原峰,峰电流与扫速呈线性关系.氧化峰电流与葡萄糖的浓度在2.0×10-6~2.4×10-5 mol/L之间有良好的线性关系(r=0.9934),检出限为6.3×10-7 mol/L.该电极具有良好的稳定性和重现性,适合于微量葡萄糖的检测. 相似文献
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壳聚糖复合碳纳米管修饰超薄碳糊电极对硝基酚异构体的同时测定 总被引:1,自引:0,他引:1
以镍镉合金为基底,将壳聚糖滴涂在碳纳米管修饰的超薄碳糊电极表面制成电化学传感器(CTSCNTs-UTCPE),利用循环伏安法(CV)、半微分伏安法研究硝基酚异构体在该电极上的电化学行为。考察了底液种类、酸碱度、扫描速度、起始电位和富集时间对检测结果的影响。与镍铬合金电极、超薄碳糊电极(UTCPE)和碳纳米管修饰超薄碳糊电极(CNTs-UTCPE)相比,由于壳聚糖和碳纳米管的协同效应,硝基酚异构体在p H 5.72的B-R中氧化电流较高。在最佳条件下,传感器对邻、间、对硝基酚的检测范围分别为4.0×10-7~8.0×10-5mol/L,4.0×10-7~8.0×10-5mol/L,8.0×10-7~8.0×10-5mol/L;检出限(S/N=3)分别为2.3×10-7,2.9×10-7,6.7×10-7mol/L。该传感器显示出良好的稳定性和抗干扰性能,可实现对人工水样中硝基酚异构体的同时检测。 相似文献
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以纳米氮化钛(TiN)为电活性物质,制备了用于检测青霉素的纳米TiN修饰碳糊电极.研究了该碳糊电极中石墨与纳米TiN的质量比、电极面积、溶液pH值及缓冲容量等因素对青霉素检测效果的影响.结果表明,在优化的条件(石墨与TiN的质量比为2∶1,电极面积为1 mm~2,溶液pH值为7.2以及缓冲容量为20 mmol/L KH_2PO_4)下,该电极检出限为2×10~(-5)mol/L,线性检测范围为4×10~(-5)~3.2×10~(-3)mol/L.利用Zeta电位及交流阻抗的方法,揭示了纳米TiN碳糊电极检测青霉素的机理为纳米TiN对青霉素的特异性吸附.纳米TiN碳糊电极展现出良好的稳定性、选择性和重复性,在青霉素检测领域具有广阔的应用前景. 相似文献
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本文结合层层组装法和电化学聚合法,制备了电子介体聚亚甲基蓝(PMB)修饰的碳纳米管(CNTs)/辣根过氧化物酶(HRP)多层膜有机过氧化物传感器。利用电化学阻抗表征了(CNTs/HRP)n的层层组装过程,探讨了不同HRP层数对传感器响应的影响,并研究了传感器对有机过氧化物过氧化氢叔丁基、过氧化氢异丙基苯的电催化还原性能。该传感器对过氧化氢叔丁基的线性检测范围为1.75×10-5~7.25×10-3mol/L,检测限为1.36×10-6 mol/L;对过氧化氢异丙基苯的线性检测范围为3.87×10-6~1.47×10-3 mol/L,检测限为6.48×10-7 mol/L。 相似文献
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对硫磷在聚乙烯吡咯烷酮修饰碳糊电极上的电化学行为及其分析研究 总被引:1,自引:0,他引:1
研究了对硫磷在聚乙烯吡咯烷酮(PVP)修饰碳糊电极(CPE)上的电化学行为,发现PVP能显著提高对硫磷的氧化还原峰电流.据此建立了一种直接测定对硫磷的电分析方法.对硫磷氧化峰电流与其浓度在2.5×10-8~1.0×10-6mol/L及1.0×10-6~1.0 × 10-5mol/L 范围内呈良好的线性关系,开路富集5 min后,检出限为7.5×10-9mol/L.在1.0×10-5mol/L的对硫磷试液中连续测定10次,其RSD为2.8%.用此方法测定了蔬菜中的对硫磷. 相似文献
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羧基化碳纳米管修饰碳糊电极伏安法测定食盐中碘酸根 总被引:2,自引:0,他引:2
应用羧基化多壁碳纳米管(c-MWCNT)修饰碳糊电极,测定食盐中的碘酸根含量.在0.1 mol/L的NaOH电解液中,当IO3-在羧基化多壁碳纳米管修饰碳糊电极表面富集60 s,电位扫速为300 mV/s时,该修饰电极在线性扫描伏安图上能出现一灵敏的阴极溶出峰,峰电位为-0.52 V,峰电流与IO3-浓度在8.0×10-10~5.0×10-8mol/L和1.0×10-7~3.0×10-6mol/L的范围内成良好线关系,相关系数分别为0.999和0.998,检出限可达1.0×10-11mol/L;该修饰电极无汞,稳定性较好,用于加碘食盐中碘酸根含量的测定灵敏度高,平均回收率为101.1%.循环伏安(CV)测试表明,碘酸根在修饰电极上电化学反应是一不可逆过程,其电极反应标准均相速率常数为0.0109 cm.s-1. 相似文献
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《中国科学B辑》2008,(10)
在碳糊电极表面制备的纳米金/TiO2中空微球复合膜可以极大地提高DNA检测的灵敏度.应用循环伏安法和电化学交流阻抗谱法研究了纳米金和TiO2中空微球在碳糊电极上的固载,并用[Fe(CN)6]3-/4-作为指示剂以电化学交流阻抗谱法表征了DNA的杂交.此DNA电化学生物传感器成功检测了来自于花椰菜花叶病毒的35S启动子基因的DNA特定序列,其动力学检测范围为1.0×10-12~1.0×10-8mol/L,检测限为2.3×10-13mol/L;同时对从一种转基因大豆中提取的外源基因胭脂碱合成酶基因终止子的聚合酶链式反应(PCR)扩增产物进行了检测,得到了满意的结果. 相似文献
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以多巴胺(DA)为模板,氨基修饰的介孔硅为载体,制得对多巴胺具有特异选择性的表面分子印迹聚合物(MIP)。将所得的MIP制成碳糊电极,用循环伏安法对多巴胺进行检测。在优化实验条件下,传感器的氧化峰电流与多巴胺浓度在1.0×10-7~2.0×10-6mol/L和2.0×10-6~1.0×10-4mol/L范围内呈良好的线性关系,相关系数分别为0.992 5和0.996 9,检出限为1.3×10-9mol/L。该传感器对DA具有较高的灵敏度和选择性,将其用于实际样品检测,结果满意。 相似文献
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抗坏血酸和尿酸在CPB现场修饰碳糊电极上的电化学行为及其选择性测定应用 总被引:2,自引:0,他引:2
研究了抗坏血酸(AA)和尿酸(UA)在裸碳糊电极(CPE)和溴化十六烷基吡啶(CPB)现场修饰碳糊电极(CPB/CPE)上的电化学行为.研究结果表明,在PBS水溶液中,AA和UA在CPB/CPE上氧化峰电流增加,峰电位负移,CPB/CPE对AA,UA电化学氧化反应产生了催化作用.微分脉冲法研究表明,在AA和UA共存体系中,AA和UA的氧化峰电位相差约220 mV,以此建立了AA和UA的电化学选择性测定方法.AA和UA的微分脉冲伏安氧化峰电流和其相应浓度分别在7.0×10-6~6.0×10-3 mol/L和5.0×10-7~6.0×10-4 mol/L的范围内呈良好的线性关系.在200倍AA共存时UA的检出限为5.0×10-6 mol/L,CPB修饰的碳糊电极直接应用于实际尿样中UA的测定. 相似文献
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Martin Sahlberg Yvonne Andersson 《Acta Crystallographica. Section C, Structural Chemistry》2009,65(3):i7-i8
Scandium magnesium gallide, Sc2MgGa2, and yttrium magnesium gallide, Y2MgGa2, were synthesized from the corresponding elements by heating under an argon atmosphere in an induction furnace. These intermetallic compounds crystallize in the tetragonal Mo2FeB2‐type structure. All three crystallographically unique atoms occupy special positions and the site symmetries of (Sc/Y, Ga) and Mg are m2m and 4/m, respectively. The coordinations around Sc/Y, Mg and Ga are pentagonal (Sc/Y), tetragonal (Mg) and triangular (Ga) prisms, with four (Mg) or three (Ga) additional capping atoms leading to the coordination numbers [10], [8+4] and [6+3], respectively. The crystal structure of Sc2MgGa2 was determined from single‐crystal diffraction intensities and the isostructural Y2MgGa2 was identified from powder diffraction data. 相似文献
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On Dialkali Metal Dichalcogenides β-Na2S2, K2S2, α-Rb2S2, β-Rb2S2, K2Se2, Rb2Se2, α-K2Te2, β-K2Te2 and Rb2Te2 The first presentation of pure samples of α- and β-Rb2S2, α- and β-K2Te2, and Rb2Te2 is described. Using single crystals of K2S2 and K2Se2, received by ammonothermal synthesis, the structure of the Na2O2 type and by using single crystals of β-Na2S2 and β-K2Te2 the Li2O2 type structure will be refined. By combined investigations with temperature-dependent Guinier-, neutron diffraction-, thermal analysis, and Raman-spectroscopy the nature of the monotropic phase transition from the Na2O2 type to the Li2O2 type will be explained by means of the examples α-/β-Na2S2 and α-/β-K2Te2. A further case of dimorphic condition as well as the monotropic phase transition of α- and β-Rb2S2 is presented. The existing areas of the structure fields of the dialkali metal dichalcogenides are limited by the model of the polar covalence. 相似文献
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[(n‐Bu)2Sn(O2PPh2)2] ( 1 ), and [Ph2Sn(O2PPh2)2] ( 2 ) have been synthesized by the reactions of R2SnCl2 (R=n‐Bu, Ph) with HO2PPh2 in Methanol. From the reaction of Ph2SnCl2 with diphenylphosphinic acid a third product [PhClSn(O2PPh2)OMe]2 ( 3 ) could be isolated. X‐ray diffraction studies show 1 to crystallize in the monoclinic space group P21/c with a = 1303.7(1) pm, b = 2286.9(2) pm, c = 1063.1(1) pm, β = 94.383(6)°, and Z = 4. 2 crystallizes triclinic in the space group , the cell parameters being a = 1293.2(2) pm, b = 1478.5(4) pm, c = 1507.2(3) pm, α = 98.86(3)°, β = 109.63(2)°, γ = 114.88(2)°, and Z = 2. Both compounds form arrays of eight‐membered rings (SnOPO)2 linked at the tin atoms to form chains of infinite length. The dimer 3 consists of a like ring, in which the tin atoms are bridged by methoxo groups. It crystallizes triclinic in space group with a = 946.4(1) pm, b = 963.7(1) pm, c = 1174.2(1) pm, α = 82.495(6)°, β = 66.451(6)°, γ = 74.922(6)°, and Z = 1 for the dimer. The Raman spectra of 2 and 3 are given and discussed. 相似文献
16.
Paul-Louis Fabre Dominique de Montauzon René Poilblanc 《Transition Metal Chemistry》1987,12(5):434-440
Summary The ability of [MoS4]2–, anions to be used as ligands for transition metal ions has been widely demonstrated, especially with Fe2+. The present study has been restricted to linear complexes such as (NEt4)2 [Cl2FeS2MoS2] and (NEt4)2[Cl2FeS2MoS2FeCl2]. Their electrochemical properties are described: upon electrochemical reduction, these compounds yield MoS2, as a black precipitate, and an iron complex in solution, assumed to be [SFeCl2]2–. The electrochemical reduction goes through two electron transfers, coupled with the breakdown of the molecular skeleton: a DISPl and an ECE mechanism. Depending on the solvent, the following equilibrium may be observed: [Cl4Fe2MoS4]2–[Cl2FeMoS4]2–+FeCl2. The equilibrium constant, KD, was evaluated by differential pulse polarography. KD is tightly related to the donor number of the solvent. 相似文献
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Marina I. Naumova Natalia V. Kuratieva Nina V. Podberezskaya Dmitry Yu. Naumov 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(5):i53-i55
The structures of the hypophosphites KH2PO2 (potassium hypophosphite), RbH2PO2 (rubidium hypophosphite) and CsH2PO2 (caesium hypophosphite) have been determined by single‐crystal X‐ray diffraction. The structures consist of layers of alkali cations and hypophosphite anions, with the latter bridging four cations within the same layer. The Rb and Cs hypophosphites are isomorphous. 相似文献
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Me2Sn(O2PPh2)2 ( 1 ), Ph2Pb(O2PMe2)2 ( 2 ), and Ph2Pb(O2PPh2)2 ( 3 ) have been synthesized by the reactions of Me2SnCl2 or Ph3PbCl with the corresponding diorganophosphinic acid in methanol. X‐ray diffraction studies show that the diorganophosphinate groups behave as double bridges between the metal atoms leading to polymeric ring‐chain structures with M2O4P2 (M = Pb, Sn) eight‐membered rings. The organic groups bonded to the metal atoms are in trans‐position in the resulting octahedral arrangement around the metal atoms. The IR and the mass spectra were reported and discussed. 相似文献
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A. -F. Shihada A. A. Said R. Al Qasmi 《Journal of Thermal Analysis and Calorimetry》1994,42(6):1313-1318
TG and DTA studies on Me3SnO2PCl2, Me2Sn(O2PCl2)2 and Ph3SnO2PCl2 were carried out under dynamic argon atmosphere. The results show that the decomposition proceeds in different stages leading
to the formation of Sn3(PO4)2 as a stable product. This compound was characterized by IR spectroscopy. Decomposition schemes involving reductive elimination
reactions were proposed. 相似文献