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ZHANG  Yan WANG  Qin 等 《中国化学》2002,20(2):168-173
Treatment of 4-amino-3-(1-aryl-5-methyl-1,2,3-triazol-4-yl)-5-mercapto-1,2,4-triazoles/2-amino-5-(1-aryl-5-methyl-1,2,3-triazole-4-yl)-1,3,4-thiadiazoles with benzaldehyde,acetone and ω-bromoacetophenone was tested and compared.The title compounds Schiff bases,amides,imidazolo [2,1-b]-1,3,4-thiadiazoles and 7H-s-triazolo[3,4-b]-1,3,4-thiadiazines have been confirmed by elemental analyses,^1H NMR,IR and MS spectra.All the compounds have also been screened for their antibacterial activities against B.subtilis,S.aureus and E.coli.  相似文献   

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史达清  路再生 《结构化学》1998,17(6):391-394
标题化合物C23H26O4是水杨醛与5,6-二甲基-1,3-环己二酮在N,N-二甲基甲酰胺中反应而得。结果通过单晶X-射线衍射法确定,其晶体属于单斜晶系,空间群P21/c,a=7.056,b=20.263,c=13.665A,β=93.32,V=1950.7A^3,Mr=366.46,Dc=1.248g/cm^3,Z=4,μ(MOKα)=0.84cm^-1,F(000)=784。晶体结构用直接法解  相似文献   

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The novel structures of organometallic compounds 3-biaryl-1-ferrocenyl-2-propene-1-ones 5 were synthesized for nonlinear optical chromophores by Suzuki cross-coupling reaction.Their structures were determined with elemental analyses,^1H NMR spectra and ^13C NMR spectra.  相似文献   

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周龙虎  张永敏 《结构化学》1998,17(4):273-276
3,4-反-4,5-反-2-氨基-3-氰基-1,3-二乙氧羰基-4,5-二(4-氯苯基)环戊烯  相似文献   

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方东  袁荣鑫 《合成化学》1997,5(1):71-74
合成了一系列新的4,6-二取代-5-硫代-1,2,4-三嗪-3-酮类化合物,并用元素分析、IR、^1H NMR及MS对其结构进行了表征。  相似文献   

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Nafion膜修饰电极的制备及其通透性研究   总被引:1,自引:0,他引:1  
制备Nafion 膜修饰玻碳电极,并研究其对多种电活性物质的通透性.以一系列不同浓度(质量分数分别为O.5%、2%、3%、5%)的Nafion 溶液,采用滴涂或蘸涂方式制成Nafion 膜修饰玻碳电极.利用循环伏安法,通过测定铁氰化钾、抗坏血酸、多巴胺等电活性物质在玻碳电极和不同厚度Nafion 膜修饰电极表面的响应情...  相似文献   

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Cu2O/nitrogen-doped grapheme(NG) nanocomposite material was prepared via a facile one step chemical reduction and characterized by means of X-ray diffraction(XRD) and scanning electron microscopy(SEM). A new electrochemical sensor was then fabricated by coating Cu2O/nitrogen-doped graphene nanocomposite with Nafion on glassy carbon electrode(Cu2O/NG/Nafion/GCE). The electrochemical response of this modified electrode toward ofloxacin was examined by cyclic voltammetry. The results indicate that Cu2O/NG/Nafion composite-modified electrode exhibits higher catalytic activity in the electrochemical oxidation of ofloxacin compared with glassy carbon electrode(GCE), Cu2O/Nafion modified electrode(Cu2O/Nafion/GCE), and N-doped graphene/Nafion modified electrode(NG/Nafion/GCE). Under optimal conditions, the peak current was found to be linearly proportional to the concentration of ofloxacin in the 0.5-27.5 μmol/L and 27.5-280 μmol/L ranges with a lower detection limit of 0.34 μmol/L, higher sensitivity of 39.32 μA·L·mmol-1 and a shorter reaction time of less than 2 s. In addition, Nafion can enhance the stability of the modified electrode and prevent some negative species. Thus the modified electrode exhibits good selectivity and a long working life. The Cu2O/NG/Nafion composite modified electrode shows promising application in electrochemical sensors, biosensors, and other related fields because of its excellent properties.  相似文献   

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将一种杂环席夫碱N,N′-2 ,6 -二乙酰吡啶缩双苯胺和Nafion修饰在铂电极上 ,然后与钴 (Ⅱ )反应 ,得到Nafion -钴席夫碱膜修饰电极。实验结果表明 ,该修饰电极具有良好的机械、化学和电化学稳定性 ,对生物分子一氧化氮的电化学氧化有显著的催化作用。以1.5次微分线性扫描伏安法测定一氧化氮 ,当浓度在2.8×10-6~8.4×10-8 mol/L范围时 ,氧化电流与浓度有良好的线性关系 ,抗坏血酸、精氨酸及亚硝酸根不干扰测定。  相似文献   

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Brilliant blue FCF‐modified glassy carbon electrodes have been prepared by cycling the Nafion (or poly(diallyldimethylammonium chloride) (PDDAC)) coated electrodes repeatedly 15 cycles in brilliant blue FCF (BB FCF) dye solution. The BB FCF molecules are incorporated into Nafion coating by cycling the film‐covered electrode between +0.3 to 1.2 V (vs. Ag/AgCl) in pH 1.5 BB FCF solution while PDDAC‐coated electrode cycled between 0 to ?1.0 V (vs. Ag/AgCl) in pH 6.5 BB FCF solution to immobilize the dye. Electrostatic interaction between dye molecule and PDDAC was predominant in PDDAC coating whereas immobilization of dye in Nafion film attributed to the combined effect of electrostatic and hydrophobic interactions. The voltammetric features of BB FCF‐modified electrodes resemble that of surface‐confined redox couples. The peak potentials of BB FCF‐incorporated PDDAC‐coated electrode were shifted to more positive potential region with decreasing pH of contacting solution. BB FCF‐modified electrodes showed electrocatalytic activity towards reduction of oxygen and oxidation of L ‐cysteine with significant decease of overvoltage compared to unmodified electrode. The BB FCF‐modified Nafion‐coated electrode was tested for its analytical applications toward determination of L ‐cysteine. The linear range of calibration plot at BB FCF‐modified Nafion‐coated electrode is 10 to 100 μM, which coincides with L ‐cysteine levels in biological fluids. Sensitivity and detection limit of the electrode are 111 nA μM?1 and 0.5 μM, respectively.  相似文献   

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The glassy carbon (GC) electrode modified with Nafion and Safranin O (SFO) was prepared and its electrochemical properties were investigated. The SFO molecules were strongly and irreversibly adsorbed on the Nafion — modified GC surface. The electrochemical behavior and mechanism for interactions of the SFO molecules with the Nafion film were investigated through cyclic voltammetric method. The electrocatalytic reduction of nitric oxide was performed at this modified electrode by cyclic voltammetric and hydrodynamic amperometric techniques. The Nafion membrane played a duel role as a matrix for the SFO immobilization and also helped to partition the nitric oxide from the solution phase. The diffusion coefficient of NO at the SFO/Nafion/GC modified electrode was calculated using chronoamperometry. The dependence of response currents on the concentration of NO was examined and was linear in the range of 0.05–1.9 mM of NO.  相似文献   

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制备了两组Nafion膜电极(膜中分别分布有带正、负电荷的过渡金属大环配离子),并用循环伏安法研究比较了这两组电极对氧催化还原性能,探讨了配离子和Nafion膜之间的静电作用对电极催化性能影响的规律,同时对其它因素的影响及电荷在Nafion膜中传递的机理也进行了讨论。  相似文献   

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基于Nafion/碳纳米粒子修饰的葡萄糖传感器   总被引:1,自引:0,他引:1  
采用滴涂法制备了Nafion/碳纳米粒子复合物修饰玻碳电极,该电极对H2O2具有良好的电催化氧化性能。还利用滴涂法制备了Nafion/碳纳米粒子复合物包裹的葡萄糖酶电化学生物传感器,该生物传感器对葡萄糖有着良好的电催化作用。应用该传感器对葡萄糖进行了检测,检测线性范围为2.0×10-6~6.0×10-3mol/L,检出限为1.6×10-6mol/L(S/N=3),实验结果表明该传感器具有良好的稳定性、重现性和抗干扰能力。对小鼠血清样品中的葡萄糖进行检测,结果令人满意。  相似文献   

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杨丽菊  彭图治 《中国化学》2000,18(5):710-714
A composite polymer carbon fiber electrode modified with Nafion and cellulose acetate is described.The modified electrode discriminates against both anionic reactants and big molecular organic compounds.The bilayer configuration is prepared in two steps.First,the carbon fiber electrode is coated with Nafion,then followed by air evaporation of the solvent,the electrode is dipped in a cellulose acetate solution and hydrolyzed for a selected time.The permeability of the film is explored by use of rotating disk electrode measurements.Parameters affecting the film electrochemistry are investigated.The resulting electrodes show high selectivity and stability in body fluids.For in-vivo voltammetry,the composite polymer modified electrode has been used for detection of the oxidative current of neurotransmitter dopamine in rat brain,while it inhabits the oxidation of anionic neurotransmitter metabolites and some electroactive compounds.  相似文献   

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A modified Nafion binder using a different dispersion solvent, dimethylacetamide (DMAc), was applied to an electrode for a unitized regenerative fuel cell (URFC). The properties of the new Nafion binder, such as dissolution rate, proton conductivity, water uptake, and IV curves, were characterized in the study. The new Nafion binder showed less brittleness, leading to good structural integrity in the electrode and improvement of stability in the URFC performance. SEM images showed that the interfacial adhesion between the membrane and the electrode was improved by using the new Nafion binder. Therefore, the new Nafion binder was suggested as a promising candidate for a binding material in the electrode of the URFC.  相似文献   

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《Electroanalysis》2005,17(24):2231-2238
Square‐wave voltammetric detection of dopamine was studied at a copper (Cu)‐(3‐mercaptopropyl) trimethoxy silane (MPS)‐complex modified electrode (Cu‐MPS). The modification of the electrode was based on the attachment of MPS onto an electrochemically activated glassy carbon electrode (GCE) by the interaction between methoxy silane groups of MPS and surface hydroxyl groups and followed by the complexation of copper with the thiol groups of MPS. The surface of the modified electrode was further coated by a thin layer of Nafion film. The surface of the Nafion coated MPS‐Cu complex modified electrode (Nafion/Cu‐MPS) was characterized using cyclic voltammetry, electrochemical quartz crystal microbalance (EQCM), scanning electron microscope (SEM), X‐ray photoelectron spectroscopy (XPS), and Fourier transform infrared (FT‐IR) spectrometry. The modified electrode exhibited an excellent electrocatalytic activity towards the oxidation of dopamine, which was oxidized at a reduced potential of +0.35 V (vs. Ag/AgCl) at a wider pH range. Various experimental parameters, such as the amount of copper, the pH, and the temperature were optimized. A linear calibration plot was obtained in the concentration range between 8.0×10?8 M and 5.0×10?6 M and the detection limit was determined to be 5.0×10?8 M. The other common biological compounds including ascorbic acid did not interfere and the modified electrode showed an excellent specificity to the detection of dopamine. The Nafion/Cu‐MPS modified electrode can be used for about 2 months without any significant loss in sensitivity.  相似文献   

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