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51.
YanCAI MingQingCHEN JuanXU PinFangWU AkashiMITSURU XiaoHuaHUAN 《中国化学快报》2004,15(9):1109-1112
Poly (N-vinylacetamide) (PNVA) was synthesized by the free radical polymerization and its samarium (Ⅲ) binary complex was prepared and characterized by means of IR, UV-vis, X-ray photoelectron spectroscopy (XPS) and fluorescence spectra. The fluorescent intensity of samarium (Ⅲ) characteristic emission was increased significantly due to efficient energy transfer from polymeric ligand to Sm (Ⅲ) ion in the complex. 相似文献
52.
各类土地利用方式都有自己的级差收益分布特点.土地使用权出让金作为政府土地收益的一部分,在制定征收标准时应符合级差收益分布规律.通过对重庆市主城区土地出让金征收标准统计分析,建立了重庆市土地出让金级差分布模型,并对其分布特点进行了评价. 相似文献
53.
HO radical is an aggressive reagent to abstract hydrogen from diverse substitutes and lead them to degradation, however, in reaction of active oxygen species with lignins, complex phenolic polymers, in dispersed lignocellulose such as pulp for environment-benign delignification, HO radicals should be eliminated as more as possible to prevent cellulose from unfavorably concomitant degradation. A reaction system of O3 is constructed under UV laser flash irradiation, and HO radicals are controlled efficiently by it. A new mechanism is proposed, for the first time, that O radicals generated from reaction of O3 with UV laser flash irradiation might be the contributor to scavenge HO radicals. 相似文献
54.
为了提高饮用水处理系统对病毒的去除效果,本研究采用静态实验,研究纳米TiO2对模型病毒—f2噬菌体的吸附去除特性,系统考察TiO2投加浓度、病毒浓度、温度及pH值等因素对吸附效果的影响.实验结果表明:f2噬菌体在纳米TiO2表面的吸附符合准二级吸附动力学模型,遵循化学吸附机理,颗粒内扩散为该吸附过程中的速率控制步骤,但不是唯一控制步骤;纳米TiO2对f2噬菌体的吸附符合Freundlich等温吸附模型(qe=27.4Ce1.24),属于多层吸附类型;在20~40℃范围内,温度对纳米TiO2的吸附性能影响不大,而酸性条件下更有利于纳米TiO2对f2噬菌体的吸附. 相似文献
55.
BI Hai-tao ZHANG Lan-ying LIU Na ZHU Bo-lin College of Environment Resources Jilin University Changchun P. R. China 《高等学校化学研究》2011,(3):407-412
Screened atrazine-mineralizing bacterium―Pseudomonas W4 was embedded inside an improved PVA- H3BO3 embedment matrix to make bio-beads to degrade atrazine. The atrazine degradation characteristics were studied. The preparation procedure of bio-beads was as follows: (1) preparing a mixture of 100, 12.5, 10, 1.5 and 1 g/L PVA, bentonite(Ca), activated carbon powder, sodium alginate and centrifuged Pseudomonas W4 bacterium, respectively; (2) the mixture was dropped into a gently stirred cross linker solution(pH... 相似文献
56.
有毒重金属离子的自由离子活度已被广泛认为是重金属最直接的活性形态,可以用来预测重金属的生物效应,而事实上生物体表的重金属离子浓度由于细胞表面膜电势的静电效应而与本体溶液中重金属的自由离子活度存在显著差异.细胞膜表面电势随溶液中离子组成变化而发生变化,本体介质中钙离子能通过电荷屏蔽和离子键结合来降低膜表面电势的电负性,从而减少阳离子如Al3+、Cu2+和Ni2+在膜表面的活度,增加阴离子如SeO42-和H2AsO4-在膜表面的活度,这种电负性降低的程度能通过Gouy-Chapman-Stern模型来量化.基于植物根表重金属离子活度可以更好地预测其生物效应.细胞膜表面电势为研究离子之间交互作用机制及其与植物效应之间的关系提供了一个全新的角度. 相似文献
57.
WANG ChunXiang XU ShunQing LV ZiQuan LI YuanYuan WANG YouJie & CHEN Tian Key Laboratory of Environment Health Ministry of Education School of Public Health Tongji Medical College Huazhong University of Science Technology Wuhan China 《中国科学:化学》2010,(5)
Persistent organic pollutants(POPs),such as dioxins,polychlorinated biphenyls(PCBs) ,and organochlorine pesticides(OCPs),which are synthetic chemicals or by-products with an intrinsic resistance to natural degradation processes,are released into the environment,resulting in the widespread dispersal and accumulation in the environment,as well as in human and ecological food chains.Due to their ubiquity in the environment and lipophilic properties,there is emerging concern over the potential risks of human ex... 相似文献
58.
LI Yu GAO Qian WANG Xiao-li DONG De-ming WANG Ao . Energy Environmental Research Centre North China Electric Power University Beijing P. R. China . College of Environment Resources Jilin University Changchun 《高等学校化学研究》2009,25(2)
Co-contamination of atrazine(AT) and cadmium(Cd) on the surficial sediments(SSs) and natural suface coating samples(NSCSs) was investigated via thermodynamic adsorption experiments. The results show that surface coatings have a stronger ability to adsorb AT owing to their higher active components compared with surficial sediments. Synergetic and antagonistic effects of Cd on the adsorption of AT were observed. Cd at a lower concentra- tion(≤4.0 mg/L) in the solid/liquid phase enhanced AT adsorption onto the... 相似文献
59.
YANG Yan-ling LI Xing GUO Can-xiong ZHAO Fu-wang JIA Feng . Key Laboratory of Beijing for Water Quality Science Water Environment Recovery Engineering Beijing University of Technology Beijing P. R. China . College of Science Beijing University of Chemical Technology Beijing 《高等学校化学研究》2009,25(2)
Iron-manganese composited oxide(FeMnO) was prepared with potassium permanganate and ferrous salt. Interface performance, charge property and structure topography of the FeMnO were investigated. Coagulation efficiency and pollution removal mechanism of the FeMnO were approached. Results show that the main compositions of the FeMnO are δ-manganese dioxide and ferric hydroxide. The specific surface area is about 146.22 m2/g. The FeMnO contains rich hydroxyl with extremely strong adsorption action and chemical ... 相似文献
60.
Synthesis and application of a hydrophobic hypercrosslinked polymeric resin for removing VOCs from humid gas stream 总被引:1,自引:0,他引:1
A hydrophobic hypercrosslinked polymeric resin LC-1 was prepared and characterized.The properties of LC-1 resin were compared with those of a commercial hypercrosslinked polymer NDA-201 resin.In addition,the dynamic adsorption of trichloroethylene(TCE)onto LC.1 under dry and humid conditions at 303 K was investigated,the result shows that LC-1possesses high hydrophobic property and can remove TCE from gas stream without effect of high humidity efficiently. 相似文献