Pd/activated carbon sorbents for mid-temperature capture of mercury from coal-derived fuel gas

Higher concentrations of Hg can be emitted from coal pyrolysis or gasification than from coal combustion, especially elemental Hg. Highly efficient Hg removal technology from coal-derived fuel gas is thus of great importance. Based on the very excellent Hg removal ability of Pd and the high adsorption abilities of activated carbon（AC） for H2 S and Hg, a series of Pd/AC sorbents was prepared by using pore volume impregnation, and their performance in capturing Hg and H2 S from coal-derived fuel gas was investigated using a laboratory-scale fixed-bed reactor. The effects of loading amount, reaction temperature and reaction atmosphere on Hg removal from coal-derived fuel gas were studied. The sorbents were characterized by N2 adsorption, X-ray diffraction（XRD） and X-ray photoelectron spectroscopy（XPS）. The results indicated that the efficiency of Hg removal increased with the increasing of Pd loading amount, but the effective utilization rate of the active component Pd decreased significantly at the same time. High temperature had a negative influence on the Hg removal. The efficiency of Hg removal in the N2-H2S-H2-CO-Hg atmosphere（simulated coal gas） was higher than that in N2-H2S-Hg and N2-Hg atmospheres, which showed that H2 and CO, with their reducing capacity, could benefit promote the removal of Hg. The XPS results suggested that there were two different ways of capturing Hg over sorbents in N2-H2S-Hg and N2-Hg atmospheres.     

稀土元素镧对金鱼藻生长生理及细胞叶绿体结构的影响

研究了稀土元素镧对金鱼藻叶绿素总量、抗坏血酸氧化酶、过氧化氢酶、过氧化物酶等代谢指标和细胞叶绿体亚显微结构的影响，以及金鱼藻对镧的吸收积累作用，结果表明，短期内低浓度（２－１１０ｍｇ／Ｌ）的镧对金鱼藻生长有一定刺激促进作用，但随处理时间的延长及处理浓度的提高，抑制作用明显增强，并破坏细胞叶绿体结构；金鱼藻对镧有较强的吸收积累能力。     

中性点不接地电网中单相接地故障的分析及处理

阐述了中性点不接地电网中单相接地的特点,并分析了用绝缘监视装置和小电流接地选线装置查找故障的利弊,以及目前小电流接地选线技术可靠性差的原因.     

河口-近海环境新污染物的环境过程、效应与风险

在全球变化和人类活动双重影响下,大量陆源污染物特别是备受各国政府和民众关注的微塑料、新型持久性有机污染物以及药物和个人护理品等新污染物进入水体环境并迁移扩散,对近海生态环境安全和人体健康产生了巨大影响.综述国内外微塑料、全/多氟化合物、抗生素和内分泌干扰物等新污染物在河口-近海环境中的污染来源、时空分布和迁移传输等环境过程及其影响因素,分析探讨近海水生生态系统中新污染物产生的不良生态效应和风险,提出未来研究重点应关注河口-近海环境中多种新污染物的相互作用和新污染物产生的联合生态毒理效应及造成的生态和健康风险等,为陆海统筹下的海洋污染防治和海洋经济的健康发展提供科学依据.     

区域经济与环境协调发展的指标体系及定量评价方法研究

区域环境是区域经济持续发展的重要基础,区域经济是区域环境发展的前提和保证。两者的协调发展是区域可持续发展的必由之路。区域环境与经济协调发展的定量评价,是分析、评价经济与环境协调发展的重要工具。文章从经济发展对环境的影响和对社会的贡献程度出发建立了经济与环境协调发展评价指标体系,进而提出了区域经济与环境协调发展的定量评价方法,对区域经济与环境协调发展评价具有重要现实意义。     

三维双阴极-电Fenton法处理腌制酸菜废水的试验研究

采用三维双阴极-电Fenton法处理腌制酸菜废水,通过正交试验考察了酸菜废水中有机物去除的影响因素及其处理效果,并优化了试验条件。试验结果表明:各因素对酸菜废水COD去除率的影响程度大小依次为:pH值电流密度Fe2+用量活性炭用量极板间距电解质Na2SO4用量电解温度;通过对比分析两种电解方式对酸菜废水的处理效果,结果显示三维双阴极-电Fenton法处理酸菜废水时产生的H2O2量、电流效率、溶液中Fe2+浓度以及废水的COD去除率均高于传统单电极-电Fenton法,并分析了反应机理。三维双阴极-电Fenton法用于腌制酸菜废水处理切实可行、效果明显,为实际废水处理提供了参考。     

含砷毒剂降解产物三苯胂对大豆萌发及幼苗生长的影响

采用不同浓度三苯胂(Triphenylarsine,TPA)沙质室内培养东北代表性作物大豆,研究日本遗弃在华化学武器("日遗化武")装填毒剂的主要降解产物之——TPA(C18H15As)对大豆萌发和幼苗生长的影响。结果表明:在0 mg/kg～400 mg/kg TPA浓度范围内,大豆受到的毒性效应随浓度增大而增大,直至无法生长;试验大豆的萌发率、根长、下胚轴长和株高等形态指标均随着培养介质中TPA浓度的增加而出现抑制效应明显增加的趋势;其中根系是大豆幼苗期砷累积的主要器官,也是对环境TPA毒害效应最敏感、响应最早的部位之一。日遗华武泄漏造成的土壤污染若处理不当会对埋藏地种植的大豆作物生长产生影响。     

In vitro characteristics of human fetal cells obtained from chorionic villus sampling and amniocentesis

In vitro characteristics of human fetal cells have been investigated after chorionic villus sampling at the first trimester and amniocentesis at the second trimester of pregnancy. Light microscopy revealed heterogeneous morphology of cell types in both the chorionic villus culture and the amniotic fluid cultures. Based on the experiments performed, chorionic villus cells are more sensitive to pronase, trypsin, and versene during subculture and have a higher DNA content per single cell and release more [¹²⁵I]-Beta-human chorionic gonadotropin into culture medium than those found in amniotic fluid cells. The practical applications of this study are discussed.     

Effect of platinum on the photocatalytic degradation of chlorinated organic compound

TiO2 nanoparticles, doped with di erent Pt contents, were prepared by a modified photodeposition method using Degussa P-25 TiO2, H2PtCl6 6H2O and methanol as the solvents. The physicochemical properties of Pt/TiO2 were investigated by the nitrogen adsorption and desorption isotherm measurement technique, X-ray di raction analysis and photoluminescence spectra, respectively. Reaction rates from photocatalytic removal of dichloromethane over Degussa P-25 TiO2 and Pt/TiO2 were evaluated. The average diameter and BET surface area of the TiO2 catalyst particles were 300 nm and 50 m2/g, respectively. The degradation e ciency was 99.0%, 82.7%, 55.2%, and 57.9% with TiO2 at inlet concentrations of 50, 100, 200, and 300 ppm, respectively. And the degradation e ciency was 99.3%, 79.7%, 76.5%, and 73.4% with a 0.005 wt.% Pt/TiO2 at inlet concentrations of 50, 100, 200, and 300 ppm, respectively. In addition, we found that the photoluminescence emission peak intensities decreased with increases in the doping amount of Pt, which indicates that the irradiative recombination was weakened. Furthermore, the results showed that the UV/0.005 wt.% Pt/TiO2 process was capable of e ciently decomposing gaseous DCM in air.     

美国加州南海岸区域清洁空气激励市场项目概况及进展

目前中国一些地区正在试点探索实施区域性排污交易项目。美国是世界上最早将排污交易理论付诸实践的国家,作为该国最早的区域性大气污染物排污交易计划之一,加州"区域清洁空气激励市场"项目自1994年开始运行。这一排污交易项目不仅实现了氮氧化物与硫氧化物减排目标,而且形成了相对健全的排污交易规则。"区域清洁空气激励市场"的总量控制机制、初始分配和交易规则与排污交易市场运行经验,对中国地方性排污交易项目设计具有重要的借鉴意义。