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61.
Square-wave voltammetry with the hanging drop mercury electrode as the working electrode was used for the determination of
ultratraces of explosives in aqueous solution. It was shown that the strong pressure dependence of the pneumatically controlled
multimode electrode system of a conventional Metrohm apparatus could be compensated by an additional pressure regulation,
through which the pressure variations could be decreased when switching from deaeration to the static measurements. By using
square-wave voltammetry with this electrode system after this modification the limits of detection for 2,4,6-trinitrotoluene
(TNT) and other TNT-metabolites could be decreased down to 0.2 μg L−1 when using a measurement time of 6 min. Also a simultaneous determination of TNT and hexahydro-1,3,5-trinitro-1,3,5-triazine
(RDX) was shown to be possible over a wide linear range and the detection limits then were 2.2 μg L−1 for TNT and 25 μg L−1 for RDX. By applying the highly stable and adjustable pressure as mentioned before, the calibrations could be kept stable
over a period of up to 1 week. 相似文献
62.
Nadica Ivošević DeNardis Vera Žutić Vesna Svetličić Ranieri Urbani 《Electroanalysis》2007,19(4):473-478
In situ amperometric characterization of an aggregating system in terms of molecular adsorption and single microparticle interactions at the electrode interface is demonstrated using a model system: alginate/Ca(II) in an aqueous electrolyte solution. Recording of chronoamperometric curves of oxygen reduction at the dropping mercury electrode is designed for detection of dip‐shaped signals of individual gel microparticles. By addition of Ca(II) decrease of alginate adsorption is accompanied by appearance of signals indicating vesicle type association of alginate molecules and microparticles of gel phase. AFM imaging provided evidence of initial stage in calcium alginate gel formation. 相似文献
63.
64.
倒数示波计时电位法在合金样品测定中的应用 总被引:2,自引:0,他引:2
应用倒数示波计时电位法,在含有吸附络合物的溶液中,采用桂汞电极作为极化电极,测定了Cu^2+、Ni^2+、Cd^2+、Pb^2+等几种金属离子的检测下限,并通过沿(dE/dt)-1 ̄E曲线上的峰高对合金样品进行定量分析,得到满意结果。实现了示波分析由常量到微量的飞跃。 相似文献
65.
Jung-Hoon Oh Mun-Chual Rho Hyeong Kyu Lee Jae Nyoung Kim Sang-Hun Jung 《Tetrahedron letters》2004,45(38):7077-7079
Asymmetric synthesis of four possible stereoisomers of (9,10)-epoxyheptadecan-4,6-diyn-3-one was accomplished, and the absolute configuration of the naturally occurring (9R,10S)-epoxyheptadecan-4,6-diyn-3-one (1) was elucidated. 相似文献
66.
S. V. Fokin G. V. Romanenko M. Baumgarten V. I. Ovcharenko 《Journal of Structural Chemistry》2003,44(5):864-869
The organomercury biradical HgL2 (L is deprotonated 4,4,5,5-tetramethyl-2-imidazoline-3-oxide-1-oxyl) is capable of performing the bridging function for design of multinuclear heterospin systems. This paper describes synthesis and crystal structure of HgL2 and the first multinuclear complexes of Cu(hfac)2 with HgL2. 相似文献
67.
在极谱催化波和吸附波方面,国内进行了大量的研究,但汞的络合物吸附波至今未见报道。钯试剂已用于光度法测定钯等。我们在研究该试剂与金属离子络合的极谱行为时发现,在硼砂介质中,试剂与Hg~(2+)可形成电活性络合物并可用于汞的测定。 相似文献
68.
An [Hg6O2]-cationic (r) octahedron atomic group has been isolated in a number of mercury oxohalide structures. The octahedron is constructed from two edge-sharing oxo-centered [Hg4O] tetrahedra. For -Hg3O2Cl2, -Hg3O2Cl2, Hg2OI, [Hg2]3O2Cl2, [Hg2]3HgO3Cl2, Hg5O4Cl2, and some other compounds, the geometrical parameters of their crystal structures depend on the dimensions and mutual packing of the cationic r-octahedra and the individual [Hg4O] tetrahedra, if any. 相似文献
69.
碳纤维汞膜微电极1.5次微分伏安法测定米托蒽醌的研究 总被引:4,自引:1,他引:4
米托蒽醌(MXT)能吸附在碳纤维汞膜微电极表面,阴极溶出时,产生一个灵敏的1.5次微分溶出峰,其峰电流和米托葱酿的浓度在1.0×10-5mol/L~1.3×10-9mol/L范围内具有良好的线性关系,经3min的富集,检出限可达1.0×10-10mol/L,据此建立了测定MXT的灵敏的新方法,本文讨论了实验条件,并对血样中的MXT进行了测定。 相似文献
70.
(+)-Xyloketal D was prepared in a one-pot multistep domino reaction by heating optically active 5-hydroxy-4-methyl-3-methylenepentan-2-one (R) in toluene with 2,4-dihydroxyacetophenone. The absolute configuration of the natural product was confirmed by preparation of the starting enone from a lactone of established absolute configuration. 相似文献