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151.
Sulfonated poly(arylene ether sulfone)(SPAES) copolymer with degree of sulfonation of 1.0 was synthesized and characterized.A series of SPAES-TiO_2 hybrid membranes with various contents of nano-sized TiO_2 particles were prepared and characterized through sol-gel reactions.Scanning electron microscopy(SEM) images indicated the TiO_2 particles were well dispersed within polymer matrix.These composite membranes were evaluated for proton exchange membranes(PEMs) in direct methanol fuel cell(DMFC).These mem... 相似文献
152.
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
153.
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
154.
铈铁复合氧化物阴离子吸附剂的表面酸碱特性研究 总被引:1,自引:0,他引:1
研究了用于水体砷等有害阴离子去除的稀土铈铁复合氧化物吸附剂的表面酸碱特性。利用电位滴定实验求定了铈铁复合氧化物吸附剂、铁氧化物和铈氧化物的表面质子电荷密度s0、零电荷点pHzpc (分别为5.8,6.2和6.8),表明特性吸附在砷等的去除中起主要的作用,铈铁复合氧化物吸附剂的表面总吸附位NS为4.1×10-3mol/L,运用表面络合恒定容量模式求算此复合氧化物吸附剂的表面固有酸度常数pKa1和pKa2,为进一步研究有害阴离子与去除材料的表面络合作用机制提供了重要参数。 相似文献
155.
In situ chemical oxidation of aniline by persulfate with iron(Ⅱ) activation at ambient temperature 总被引:1,自引:0,他引:1
Donna E.Fennell 《中国化学快报》2010,21(8):911-193
<正>The kinetics of aniline degradation by persulfate processes with iron(Ⅱ) activation at ambient temperature was investigated in this study.With iron(Ⅱ) as initiator,the oxidation reactions were found to follow a biphasic rate phenomenon:a rapid transformation followed by a slow but sustained oxidation process.In the first 30 s,the reaction mainly relies on the persulfate-Fe~(2+) reaction in which aniline is oxidized rapidly.After 30 s,the aniline was still oxidized but the rate of reaction tended to be slower and the rates were clearly linear-proportional.After the initial fast oxidation,the reactions appeared to follow a pseudo-first-order model. 相似文献
156.
FENG JingLan WANG GuoLiang SUN JianHui SUN ShengPeng &LIU XiangFu Henan Key Laboratory for Environmental Pollution Control College of Chemistry Environmental Sciences Henan Normal University Xinxiang China State Key Laboratory of Pollution Control Resources Reuse College of Environmental Science Engineering Tongji University Shanghai China 《中国科学:化学》2010,(5)
The concentrations of Cd,Cr,Cu,Ni,Pb and Zn were determined in the water and surface sediments from the Henan reaches of the Yellow River.Twenty-three sampling sites along the Yellow River and its tributaries were selected.Generally,metal concentrations were found to decrease in sequences of Zn>Cu>Pb>Cr>Ni>Cd in water and Zn>Cr>Pb>Ni>Cu>Cd in sediments.High levels of metal concentration were determined at a few stations of the river and its tributaries,such as Yiluo River,Si River and Qin River.The pollutio... 相似文献
157.
一种简化的重氮化法制备固定化酶的载体合成方法 总被引:2,自引:0,他引:2
重氮化法是固定化酶时常用的一种方法。用多孔玻璃等无机物作载体时,一般是先用g-氨丙基三乙氧基硅烷与多孔玻璃等载体反应[1,2],生成烷基胺玻璃,然后与对硝基苯酰氯反应,产物经过还原,生成带有芳胺的衍生物,最后进行重氮化。本文通过烷基胺与对氨基苯甲酸反应,直接生成芳胺的衍生物,比常用的方法缩短了一步。通过在新合成的载体上对木瓜蛋白酶进行固定化,研究了固定化条件对酶活力回收的影响,最适固定化条件如下:pH为7.0,时间为6h,酶量为240mg/g载体,并比较了固定化酶和溶液酶的有关性质,考察了固定化酶的操作稳定性。结果表明,用这种方法合成的载体固定化酶,其对热稳定性、操作稳定性及产率都比较理想。 相似文献
158.
考察了氯化和臭氧预氧化对污水中DOM 的发光细菌急性毒性的影响. 结果表 明, 臭氧预氧化处理后发光细菌的急性毒性显著增强. 利用树脂吸附将臭氧预氧化前后 的DOM 分离为疏水性和亲水性等6 种组分, 对DOM 的6 种组分分别氯化, 考察了氯化 前后各组分的发光细菌急性毒性. 结果发现, 亲水性组分的比例在臭氧预氧化后明显增 加, 且亲水性有机物的急性毒性显著强于疏水性有机物. 结合电位滴定和傅立叶红外分 析发现, 与疏水性有机物相比, 亲水性有机物具有较高含量的ph-OH 官能团. 相似文献
159.
The determination method of L-phenylalanine(LPA) by fluorescence quenching was developed.The assay was based on the combination of the cucurbit[7]uril(CB[7]) with palmatine hydrochloride(PAL) reaction.In the presence of CB[7],the fluorescence of PAL was quenched by LPA which can be employed to detect LPA.Under the optimal conditions,a linear range 3.63×10-8- 9.68×10-6mol/L and a detection limit 1.27×10-8mol/L of LPA were obtained.The relative standard deviation(R.S.D) was 1.8%obtained from a series of 11 standards each containing 6.05×10-6 mol/L of LPA.This paper also discusses the mechanism of fluorescence indicator probe. 相似文献
160.
FAN Jing ZHU GuiFen WANG HaiBo & WANG JianJi Henan Key Laboratory for Environmental Pollution Control Key Laboratory for Yellow Huai River Water Environmental Pollution Control Ministry of Education School of Chemical Environmental Sciences Henan Normal University Xinxiang China 《中国科学B辑(英文版)》2011,(6)
Trace of Pb(Ⅱ) has been on-line separated and enriched from environmental samples and wastewater by using the self-made alizarin violet functionalized silica gel micro-column coupling with a sequential injection sampling technology. The determination is based on the color reaction of Pb(Ⅱ) with iodide and crystal violet to form an ionic association complex in the presence of polyvinyl alcohol and hydrochloric acid. The use of the microcolumn can prevent the interference of most familiar metal ions, and ther... 相似文献