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11.
A plasma induced degradation process has been studied to treat 4-nitrotoluene (4-NT) present as an aqueous pollutant. The plasma was locally generated from a glow discharge around a tip of a platinum anode in an electrolytic solution. The influence of initial pH and Fe2+ on the degradation was examined. Major intermediates resulting from the degradation process were identified. Amongst the aromatic intermediates, p-hydroxybenzoic acid was the predominant degradation product. The formation of oxalic acid, malic acid was also observed. The final products of degradation were NH 4 + , NO 3 and CO2. Based on the analysis of intermediates and the kinetic considerations, the degradation was shown to follow a pseudo-first order reaction hence, a possible reaction pathway was proposed.  相似文献   
12.
For the first time, the feasibility of a molecularly imprinted liquid phase deposition (LPD) thin film has been demonstrated. Thin films of titanium oxide imprinted with L-glutamic acid were prepared by the LPD method on a gold-coated quartz crystal microbalance. The imprinted molecule could be removed upon treatment with immersion in deionized water. A sensor was developed on the basis of this method and showed good sensitivity, selectivity, and reproducibility to the template molecule. An equation was deduced to characterize the interaction between molecularly imprinted films and the template by virtue of Scatchard analysis. X-ray photoelectron spectroscopy was introduced to show the evidence for the molecular imprinting phenomenon. The linear relationship between the frequency shifts and the concentration of analyte in the range of 10-200 microM was obtained. LPD proves to be a powerful method for imprinting titanium oxide thin films.  相似文献   
13.
用薄层池原位紫外光谱电化学法研究了辅酶Ⅰ(NAD)在银电极上的电化学配位反应机理。实验结果表明:NAD能与溶出的银离子生成配合物,该配合物的配位反应是一种可逆过程,用光谱电化学的Nernst图解分析获得银离子与NAD配合物的主要存在形式是[Ag(NAD)2+,银离子是与NAD分子的腺嘌呤基团形成配合物的。配合物的银离子与银电极表面发生异相电子交换反应,该电化学反应是受吸附控制的准可逆电极过程。  相似文献   
14.
亲电性对醌二甲烷与富电子烯烃的电荷转移聚合   总被引:1,自引:0,他引:1  
概述了亲电性对醌二甲烷与富电子烯烃电荷转移聚合的最新进展,着重介绍聚合的一般特征、引发机理、链增长机理,以及单体结构、溶剂对聚合反应的影响。  相似文献   
15.
研究表明,许多过渡金属配合物具有抗癌抑菌性能,刃我们在以前工作基础上又合成了三种由邻香兰素衍生的新型希夫碱配合物,对他们进行了非等温热重分析,并采用积分法和微分法相结合的方法,推断出了它们的热分解反应机理.  相似文献   
16.
Cyanex301的纯化及其特性   总被引:7,自引:0,他引:7  
陈靖  焦荣洲 《应用化学》1996,13(2):45-48
研究了用Cyanex301[TM]铵盐在苯中重结晶以纯化Cyanex301的方法,该法收率62.4%,产品纯度>99%。测定了经纯化后产品的红外光谱,研究了纯化产品在-水正庚烷体系中的分配平衡及其在正庚烷中的缔合,浓度在0.2~1.0mo1/L范围,Cyanex301主要以二聚形式存在。  相似文献   
17.
The oligo(p-phenylene vinylene)-porphyrin-oligo(p-phenylene vinylene) (P-OPVn, n=2, 4, where n is the number of phenyl rings) and the complex with Zn2+ based on P-OPVn were synthesized for investigating their photophysical properties via UV-vis, voltammetry, steady-state and time-resolved fluorescence spectra. In these molecules two OPV moieties as energy donors were linked to porphyrin center by virtue of Wittig reaction. The detailed studies of photophysical properties indicate that OPV group can act as an antenna unit for effective intramolecular energy transfer.  相似文献   
18.
Yongjun Liu  Yongmin Zhang 《Tetrahedron》2004,60(22):4867-4873
Prompted by samarium metal in DMF with TMSCl or iodine as an activator, or by SmI2/THF system, diarylmethanones react readily with DMF to afford benzoins in moderate to good yields via rearrangement of aryl groups. As for asymmetric diarylmethanones, products resulting from the migration of either aryl group were obtained, where the migration of aryl groups shows certain priority.  相似文献   
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20.
Metal azides have attracted increasing attention as precursors for synthesizing polymeric nitrogen. In this article, we report the amorphous polymerization of nitrogen by compressing cupric azide. The ab initio molecular dynamics simulations show that crystalline cupric azide transforms into a disordered network composed of singly bonded nitrogen at a hydrostatic pressure of 40 GPa and room temperature. The transformation manifests the formation of a π delocalization along the disordered Cu-N network, thus resulting in a semiconductor–metal transition. The estimated heat of formation of the amorphous polymeric nitrogen system is comparable to conventional high-energy-density materials. The amorphization provides an alternative route to the polymerization of nitrogen under moderate conditions.  相似文献   
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