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31.
采用溶胶-凝胶法制备酞菁-TiO2光催化剂,并分别掺杂铁、铜、钴、镍元素。酞菁作为光敏化剂,提高TiO2在可见光下对有机染料的降解效果。采用SEM对催化剂进行表征,研究在可见光下酞菁-TiO2光催化剂对5种有机染料(甲基橙、甲基红、甲酚紫、亚甲基蓝和孔雀石绿)的降解效果,结果表明,酞菁铁-TiO2,酞菁钴-TiO2,酞菁铜-TiO2,酞菁镍-TiO2均能有效降解这几种有机染料,光催化反应300 min后降解率达92%。比较4种催化剂对甲基橙的降解率,酞菁钴-TiO2催化剂降解效果最明显,以下是酞菁铁、酞菁镍和酞菁铜-TiO2催化剂。 相似文献
32.
论述了输油泵站控制系统及微波通信系统遭受雷击的危害及原因,有针对性地采取了各种防雷的有效措施,完善微波通讯和站控及网络防雷保护系统,为确保输油安全生产提供了有利保证. 相似文献
33.
在硫酸系统中,通过水平衡分析计算烟气带入净化工序的SO2体积分数和含水量,确定净化工序的能力,控制干燥塔进口烟气温度,使干吸工序生产出合格产品;通过计算,烟气带入净化工序的水量小于产品带出的水量,制酸净化污水经过污水处理工序处理后返回到净化工序重复使用,实现净化污水零排放,消除对环境的污染. 相似文献
34.
Yanhui Li Bing Xi Quansheng Zhao Fuqiang Liu Pan Zhang Qiuju Du Dechang Wang Da Li Zonghua Wang Yanzhi Xia 《环境科学学报(英文版)》2011,23(3):404-411
Kaolin has been widely used as an adsorbent to remove heavy metal ions from aqueous solutions. However, the lower heavy metal
adsorption capacity of kaolin limits its practical application. A novel environmental friendly material, calcium alginate immobilized
kaolin (kaolin/CA), was prepared using a sol-gel method. The e ects of contact time, pH, adsorbent dose, and temperature on Cu2+
adsorption by kaolin/CA were investigated. The Langmuir isotherm was used to describe the experimental adsorption, the maximum
Cu2+ adsorption capacity of the kaolin/CA reached up to 53.63 mg/g. The thermodynamic studies showed that the adsorption reaction
was a spontaneous and endothermic process. 相似文献
35.
The effects of the annealing and partial substitution of Y for La on the structural and electrochemical properties of La1-xYxNi3.55Mno.4Alo.3Cro.75 (x = 0, 0.1 and 0.2) alloys were reported in the present work. The single-phased CaCu5-type structure was retained after La was partially substituted by Y. However, the increase of Y content leads to decrease of the lattice parameters and the unit-cell volume. The annealed Lao.9Yo.1Ni3.55Mno.4Alo.3Coo.75 alloys shows typical isometric microstructure, indicating that the composition segregation is improved by annealing. Y substitution for La in the alloys is effective to improve the electrochemical properties at both room temperature and high temperature. A critical substitution content of Y is found at x = 0.1. 相似文献
36.
Catalytic bubble-free hydrogenation reduction of azo dye by porous membranes loaded with palladium (Pd) nanoparticles was studied for the first time. The effects of Pd loading, dye concentration and reuse repetitions of membranes were investigated. In reduction, the dye concentration decreased whereas the pH rose gradually. An optimal Pd loading was found. The catalytic membranes were able to be reused more than 3 times. 相似文献
37.
Jun Bai Xiuhong Yang Ruiying Du Yanmei Chen Shizhong Wang Rongliang Qiu 《环境科学学报(英文版)》2014,26(10):2056-2064
Mechanisms of soil Pb immobilization by Bacillus subtilis DBM, a bacterial strain isolated from a heavy-metal-contaminated soil, were investigated. Adsorption and desorption experiments with living bacterial cells as well as dead cells revealed that both extracellular adsorption and intracellular accumulation were involved in the Pb2+removal from the liquid phase. Of the sequestered Pb(II), 8.5% was held by physical entrapment within the cell wall, 43.3% was held by ion-exchange, 9.7% was complexed with cell surface functional groups or precipitated on the cell surface, and 38.5% was intracellularly accumulated.Complexation of Pb2+with carboxyl, hydroxyl, carbonyl, amido, and phosphate groups was demonstrated by Fourier transform infrared spectroscopic analysis. Precipitates of Pb5(PO4)3OH, Pb5(PO4)3Cl and Pb10(PO4)6(OH)2that formed on the cell surface during the biosorption process were identified by X-ray diffraction analysis. Transmission electron microscopy–energy dispersive spectroscopic analysis confirmed the presence of the Pb(II)precipitates and that Pb(II) could be sequestered both extracellularly and intracellularly.Incubation with B. subtilis DBM significantly decreased the amount of the weak-acid-soluble Pb fraction in a heavy-metal-contaminated soil, resulting in a reduction in Pb bioavailability, but increased the amount of its organic-matter-bound fraction by 71%. The ability of B.subtilis DBM to reduce the bioavailability of soil Pb makes it potentially useful for bacteria-assisted phytostabilization of multi-heavy-metal-contaminated soil. 相似文献
38.
The brominated products, formed in chlorination treatment of benzophenone-4 in the presence of bromide ions, were identified, and the formation pathways were proposed.Under disinfection conditions, benzophenone-4 would undertake electrophilic substitution generating mono- or di-halogenated products, which would be oxidized to esters and further hydrolyzed to phenol derivatives. The generated catechol intermediate would be transformed into furan-like heterocyclic product. The product species were p H-dependent,while benzophenone-4 elimination was chlorine dose-dependent. When the chlorination treatment was performed on ambient water spiked with benzophenone-4 and bromide ions, most of brominated byproducts could be detected, and the acute toxicity significantly increased as well. 相似文献
39.
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