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41.
We used a carbon paste electrode modified with multi-walled carbon nanotubes as a working electrode and studied the electrochemical
behavior of zirconium-alizarin red S complex on it. It was found that the modified electrode exhibited a significant catalytic
effect toward the reduction of free alizarin red S and the complex. The second derivative linear scan voltammograms of the
complex were recorded by a polarographic analyser from 0 to −1000 mV (vs. SCE), and it was found that the complex can be adsorbed
on the surface of the modified electrode, yielding a peak at about −470 mV, corresponding to the reduction of alizarin red
S in the complex. The linear range was found to be 2.0 × 10−11–8.0 × 10−7 mol L−1, and the detection limit was 1.0 × 10−11 mol L−1 (S/N = 3) for 3 min accumulation. The procedure was successfully applied to the determination of trace amounts of zirconium in
the ore samples.
Correspondence: Pei-Hong Deng, Department of Chemistry and Material Science, Hengyang Normal University, Hengyang Hunan 421008,
P.R. China 相似文献
42.
Introduction Overall exposure to lead is of public health concern because of several hazardous effects that may occur to human beings. Lead poisoning may provoke irritability, anorexia, malaise and headache. Intoxication progress may lead to attacks of abdominal pain until coma and death.1 The determination of trace lead in variety of en-vironmental samples is of great importance since lead is recognized as a cumulative poison to animals and hu-mans. There is a constant demand for improved an… 相似文献
43.
普鲁士蓝修饰电极结合硅溶胶-凝胶技术制备高灵敏葡萄糖传感器 总被引:9,自引:0,他引:9
基于普鲁士蓝修饰玻碳电极结合二氧化硅溶胶 凝胶固定化酶技术构造具有“三明治”式结构的酶电极。考察了酶电极对葡萄糖的电化学响应以及操作条件。结果表明 :所制备的传感器在pH 6 .5 ,电位为- 0 .0 5V条件下对葡萄糖在 0~ 5mmol/L呈线性响应 ,响应时间为 12s ,检出限为 0 .0 2mmol/L ,灵敏度高达1 182 μA/ (mmol·L-1)。传感器的稳定性好 ,4 5d其响应值仍保持 90 %。 相似文献
44.
QiongCHENG TuZhiPENG XiaoBoHU CatherineF.YANG 《中国化学快报》2004,15(12):1473-1476
A novel fibroin modified electrode with ion recognition was reported. The membrane with isoelectric point of pH 4.5, was modified on graphite and carbon fiber electrodes. The pH-responsive ion recognition of the modified electrode was investigated by use of some neurocompounds. The fibroin carbon fiber electrode has been used for in-vivo determination. 相似文献
45.
Y. N. Bolbukh V. A. Tertykh B. Gawdzik 《Journal of Thermal Analysis and Calorimetry》2006,86(1):125-132
A complex approach including thermogravimetry,
differential thermal analysis and differential scanning calorimetry was applied
to study characteristics of non-filled and filled porous copolymers of divinylbenzene
with styrene or some acrylic monomers: di(methacryloyloxymethyl)naphthalene,
methacrylic ester of p,p’-dihydroxydiphenylpropane
diglycidyl ether, and dimethacrylglycolethylene. High disperse silicas with
the grafted methyl and silicon hydride groups in the surface layer were used
as fillers. The kinetic parameters of thermal degradation for composites obtained
were determined by different methods. 相似文献
46.
Nafion-汞膜化学修饰电极测定GPT的研究 总被引:2,自引:0,他引:2
Nafion-汞膜化学修饰电极测定GPT的研究金利通,叶建山,史占玲,方禹之(华东师范大学化学系,上海,200062)关键词Nafion-汞膜化学修饰电极,谷丙转氨酶,α-酮戊二酸正常人血清中转氨酶活力很小,而组织中转氨酶活力很高.当组织病变时,细胞... 相似文献
47.
48.
V. R. Gorelik V. F. Tarasov S. R. Shakirov E. G. Bagryanskaya 《Russian Chemical Bulletin》2008,57(7):1416-1427
The multispin systems consisting of spin-correlated radical pairs (SCRPs) and stable nitroxide radicals, localized in micelles
of sodium dodecyl sulfate (SDS), were studied by ESR and pulse laser photolysis techniques. In all the systems studied, the
stable nitroxide radicals exert no effect on the shape of the ESR spectra of the SCRPs (in particular, on the shape of their
antiphase structure) and on the decay kinetics of the ESR signal of the SCRPs. In the SDS micelles, the electron spin polarization
transfer from the nonequilibrium electron spin states of the molecular triplets (SCRP precursors) is the most efficient mechanism
of generation of the electron spin polarization in nitroxide radicals. The experimental data also show that the nitroxide
radicals and SCRP radicals are most probably distributed uniformly in the micellar phase.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1390–1401, July, 2008. 相似文献
50.
ZuoWei Xie 《中国科学:化学(英文版)》2014,57(8):1061-1063
<正>Carboranes are a class of boron hydride clusters in which one or more of the BH vertices are replaced by CH units.Unlike small boranes, carboranes are kinetically and thermodynamically very stable as well as relatively chemically inert, which are often called three-dimensional relatives of benzenes. They are finding many applications in medicine as boron neutron capture therapy(BNCT) agents, in nanomaterials/supramolecular design as building blocks, and as ligands for transition metals [1]. However, their unique structures make derivatization difficult, which limits their application scope. To this end, there is a need to develop 相似文献