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原位光谱电化学技术对有机染料分子电极过程的研究 总被引:2,自引:0,他引:2
原位光谱电化学技术对有机染料分子电极过程的研究①唐寅轩杨杭生沈报恩*(杭州大学化学系杭州310028)有机染料分子修饰电极在光电化学,电催化等方面的应用均有较好的效果,因而受到人们极大的注意.近年来已经制备成功许多染料化学修饰电极[1].原位光谱电化... 相似文献
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新型半菁染料阳离子和含锌硫代富瓦烯配阴离子的电荷?… 总被引:1,自引:1,他引:0
对一种新型半菁发色基团的碘化物-(反式)-N-十八烷基-4-(2-二甲基氨基)苯基)乙烯基)喹啉碘化物和含锌硫代富瓦烯配阴离子形成的电荷转移复合物:二-[(反式)-N-十八烷基-4-(2-(4-(2-二甲基氨基)苯基)乙烯基)喹啉]合硫代富瓦烯锌酸盐的成膜性以及它们的LB膜修饰ITO电极上的光电响应性能进行比较研究,用含锌硫代富瓦烯配阴离子对这种半菁发色团阳离子进行组装后,能够改善其成膜性,使单位 相似文献
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详细报道了Nafion-聚[N′,N″-(1,3-丙二亚甲基)双(1,2-苯二氨基)-N,N′,N″,N]合镍[PolyNi(Ⅱ)L]修饰微铂电极的制备及性质.实验表明,该修饰电极对NO有较高的灵敏度和选择性.当NO的浓度在2.0×10-7~1.6×10-5mol/L范围内峰电流与NO的浓度呈线性关系,相关系数r=0.994.用于血液中NO的检测,效果良好. 相似文献
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聚(L-γ-氯乙基谷氨酸酯)的合成与构象 总被引:1,自引:0,他引:1
聚(L-γ-谷氨酸酯)类化合物是近年来被广泛用于蛋白质模拟及构象[1]、药物载体[2]和液晶大分子研究[3],并可能是具有特殊场效应[4]的一类合成多肽.特别是在光电材料领域,人们发现将光致变色基团接入聚L-谷氨酸酯肽链的侧基是得到此类新型光电材料的最有效方法之一[5].由于聚L-γ-谷氨酸酯是一类具有强旋光性的蛋白质,对其进行适当的改性后将对特定的小分子对映体有识别作用[6],如将氨基糖接入聚L-谷氨酸酯的侧链就可制得能分离糖对映体的分离膜[7].因此,将聚L-谷氨酸酯的侧链功能化,从而进一步… 相似文献
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碘离子的测量方法有化学法和电化学方法等多种,电化学方法有离子选择性电极、阴极溶出伏安法等[1,2],但以上方法易受共存离子的干扰.自组装膜修饰电极具有分子识别功能,因而可用于特定物质的检测[3].末端硫醇化的聚乙二醇分子在金电极表面形成自组装膜后具有分子识别特性[4],碘离子和聚乙二醇膜有较好的相容性,可以进入膜内进而到达电极表面进行反应,而其它干扰离子较难进入.因而,该膜电极能用于碘离子测定,检测下限低,并具有较强的抗干扰能力.1 实验部分1.1 试剂及仪器 甲氧基聚乙二醇(MW=5000)等… 相似文献
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儿茶酚胺类神经递质在锇配位聚合物和Nafion双层膜修饰碳基电极上的电催化氧化及其痕量测定 总被引:4,自引:0,他引:4
多巴胺(DA)、肾上腺素(EP)和去甲肾上腺素(NE)等儿茶酚胺类神经递质是生物分子电化学研究的重要对象之一[1,2].它们在固体电极上的电子传递速率非常缓慢,且其本身或反应产物易在电极表面吸附,导致电极表面的钝化[3].利用具有特定功能的化学修饰电... 相似文献
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聚N,N-双水杨醛乙二胺合钴修饰超微电极的制备及其在一氧化氮测定中应用的研究 总被引:6,自引:0,他引:6
通过电化学聚合法制备了聚N,N-双水杨醛乙二胺合钴[polyCo(Salen)]修饰超微电极,研究了该修饰电极的电催化性质及其在一氧化氮(NO)测定中的应用.实验结果表明,polyCo(Salen)修饰超微电极对NO的测定有高的灵敏度,NO的浓度在2.0×10-8~2.8×10-6mol/L范围内,电流与浓度呈良好的线性关系,线性相关系数为0.9998,检出限为1.0×10-8mol/L;该电极进一步修饰Nafion后,生物体中常见的物质如抗坏血酸、儿茶酚胺类神经递质的代谢物、NO的氧化产物NO-2等不干扰测定.本传感器可以满足NO在体分析的需要. 相似文献
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血红素修饰电极及其催化氧还原性质 总被引:3,自引:0,他引:3
金属大环络合物(卟啉、酞箐、维生素B_(12)等)修饰电极对氧、一氧化氮和其它生物物质的催化作用[1-3]引起了化学工作者的极大兴趣,血红素是一种重要的铁卟啉化合物,是血液中血红蛋白的重要组成部分,承担携氧的任务,由于其特殊的生理功能,研究血红素修饰电极的性质和作用对进一步研究开发燃料电池具有很重大的意义.卟啉在电极上的修饰有多种方法,当卟啉或金属卟啉环侧链上具有苯氨基、苯酚基、乙烯基或吡咯等取代基时[3],可采用电氧化聚合法制备聚卟啉膜.本文采用循环伏安法在水溶液中制备了聚血红素膜电极,研究了聚… 相似文献
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Yamaguchi A Nakano M Nochi K Yamashita T Morita K Teramae N 《Analytical and bioanalytical chemistry》2006,386(3):627-632
The adsorption and longitudinal diffusion behaviors of a series of hemicyanine dyes to phospholipid vesicle membranes were
studied by second-harmonic generation (SHG) and fluorescence spectroscopies. It was observed that the longitudinal diffusion
of cationic hemicyanine dyes takes place immediately after the initial adsorption of these dyes to the outer surface of the
vesicle membrane. In contrast, hardly any amount of a zwitterionic hemicyanine dye with a sulfonate group diffused across
the vesicle membrane within the measurement time (<2000 s). Based on the difference in the time-course responses of SHG and
fluorescence spectroscopies for all of the hemicyanine dyes tested, we propose that hydration of the sulfonate group is mainly
responsible for the low diffusivity of the zwitterionic hemicyanine dye. 相似文献
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对一种新型半菁发色基团的碘化物--(反式)-N-十八烷基-4-(2-(4-(2-二甲基氨基)苯基)乙烯基)喹啉碘化物和含锌硫代富瓦烯配阴离子形成的电荷转移复合物:二-[(反式)-N-十八烷基-4-(2-(4-(2-二甲基氨基)苯基)乙烯基)喹啉]合硫代富瓦烯锌酸盐的成膜性以及它们的LB膜修饰ITO电极上的光电响应性质进行比较研究,用含锌硫代富瓦烯配阴离子对这种半菁发色团阳离子进行组装后,能够改善其成膜性,使单位面积上的半菁发色团数目增加.同时,含锌硫代富瓦烯配阴离子的强吸电子能力还影响半菁发色团的电荷分布,使之有利于电荷分离,从而提高了光电流的量子产率.在无外界影响时,其光电转化的量子产率达0.9%,是碘化物的1.8倍. 相似文献
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《Supramolecular Science》1998,5(5-6):499-500
The preparation of stable monomolecular layers and semiconducting Langmuir–Blodgett films exhibiting coupled SHG effect based on hemicyanine dye and nickel maleonitrilodithiolate is described. 相似文献
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[structure: see text] The selectivity and sensitivity of a benzothiazolium hemicyanine dye toward mercury(II) in aqueous solutions are described. Mercury ions coordinate to the dye forming a 1:1 complex. This interaction induces a color change in the dye at micromolar concentrations of mercury. Furthermore, the color change and quenching of the dye emission are selective for mercury when compared with other ions such as lead(II), cadmium(II), zinc(II), or iron(II). 相似文献
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[reaction: see text] Trimethine cyanine dye was synthesized by capture and activation of a hemicyanine intermediate on sulfonyl chloride resin followed by reaction and concomitant cleavage by a heterocyclic carbon nucleophile. A small array of dyes were synthesized and characterized to demonstrate the versatility of this chemistry for a number of hemicyanines and heterocyclic nucleophiles. 相似文献
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Kabatc J Ośmiałowski B Paczkowski J 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,63(3):524-531
The ground state (mu(g)) and excited state (mu(e)) dipole moments of 15 hemicyanine dyes were studied at room temperature. They were estimated from solvatochromic shifts of the absorption and the fluorescence spectra as function of the solvent dielectric constant (varepsilon) and refractive index (n). In this paper we applied the Stokes shift phenomena not only for the determination of the difference in the dipole moment of excited state and ground state, but to determine the value of polarizability alpha as well. The obtained results show that excited state dipole moments of hemicyanine dyes are in the range from 5 to 15 Debye, and the difference between the excited and ground state dipole moments vary from 1 to 7 Debye. The excited and ground state dipole moments difference (mu(e)-mu(g)) obtained for selected dyes are positive. It means that the excited states of the dyes under the study are more polar than the ground state ones. Additionally, the value of both polarizability (alpha) and the Onsager radius (a) of each investigated hemicyanine dye molecule are determined, and the ratio of alpha/a(3) for each dye were calculated, which oscillate from 0.29 to 5.21. The increase in dipole moment has been explained in terms of the nature of excited state and its resonance structure. 相似文献
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Beata Jędrzejewska 《Colloid and polymer science》2013,291(9):2225-2236
This article introduces tri-cationic hemicyanine dye employed as a visible-light photoinitiator of acrylic monomers polymerization. This dye, in combination with borate anions, was found to be a very effective photoinitiating system. The kinetics of trimethylolpropane triacrylate polymerization was studied by a microcalorimetric method. The photoredox pair concentration, the co-initiator structure as well as the light intensity strongly affected the progress of the polymerization, leading, for example, to an increase in the polymerization rate and quantum yield of the process. The efficiency of these photoinitiators was discussed on the basis of the free energy change for electron transfer from a borate anion to an excited hemicyanine dye cation. The ?G el values were estimated for photoredox pairs containing a series of phenyltrialkylborate anions and one styrylpyridinium dye cation. The relationship between the rate of polymerization and the free energy of activation for electron transfer reaction gives the dependence predicted by the classical theory of electron transfer. The photoinitiating abilities of the selected novel photoredox pairs (BPB61, BPB7, BPB8, and BPB9) are comparable with the photoinitiating efficiency of commercially available photoinitiators. 相似文献
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A series of novel hemicyanine dye-β-cyclodextrin compounds: mono-6-deoxy-β-cyclodextrin-6-[p-(p-substituted styryl)pyridium] p-totylfulfonates were synthesized by the condensation of mono-6-deoxy-β- cyclodextrin-6-(p-methyl pyridinium) p-toluenesulfonate with (un)substituted benzaldehydes. Their structures were established by 1^H NMR, IR, UV-Vis and elemental analysis. The absorption and fluorescence properties of the novel compounds were measured in solution and the photostability of a selected hemicyanine dye-β-cyclodextrin compound was also investigated. 相似文献