厄尔尼诺-拉尼娜事件对新疆环境气候的影响研究

基于近54年发生的厄尔尼诺/拉尼娜事件和新疆气候资料,分析新疆环境气候变化特点表明:1961年以来新疆降水量和气温均呈现明显增加的趋势.厄尔尼诺/拉尼娜事件呈现出起伏波动的特点,且1980年以后波动趋势更为剧烈,厄尔尼诺事件发生强度要大于拉尼娜事件.强厄尔尼诺年极端降水事件增多.厄尔尼诺/拉尼娜事件年对新疆各地区降水、气温影响不同,厄尔尼诺年塔城、阿勒泰北部、巴州北部、南疆西部喀什至和田一带增湿明显,阿勒泰东部、哈密北部升温作用显著.     

褐土施Ni对小白菜的生物效应及临界值的研究

研究了褐土施镍(N i)对小白菜生长发育及矿质营养吸收与积累的影响。依据小白菜生物量的变化,用茎叶N i含量及土壤有效态N i含量来表征土壤N i污染的毒性临界值。结果表明,施N i量在0~25 mg.kg-1范围促进小白菜鲜重增加、干物质积累降低;随施N i量增加,生物量呈极显著下降。褐土施N i影响矿质营养元素的吸收和积累,且随施N i量的增加表现出一定的协同和拮抗作用。以生物量减产10%为依据,确定褐土施N i的毒性临界值为:土壤全N i含量57.22 mg.kg-1,土壤有效态N i含量8.59 mg.kg-1(用DTPA提取液)和茎叶N i含量20.51 mg.kg-1。     

Macroporous Ni foam-supported Co3O4 nanobrush and nanomace hybrid arrays for high-efficiency CO oxidation

Herein, we reported the synthesis of well-defined Co_3O_4 nanoarrays(NAs) supported on a monolithic three-dimensional macroporous nickel(Ni) foam substrate for use in highefficiency CO oxidation. The monolithic Co_3O_4 NAs catalysts were obtained through a generic hydrothermal synthesis route with subsequent calcination. By controlling the reaction time,solvent polarity and deposition agent, these Co_3O_4 NAs catalysts exhibited various novel morphologies(single or hybrid arrays), whose physicochemical properties were further characterized by using several analytical techniques. Based on the catalytic and characterization analyses, it was found that the Co_3O_4 NAs-6 catalyst with nanobrush and nanomace arrays displayed enhanced catalytic activity for CO oxidation, achieving an efficient 100% CO oxidation conversion at a gas hourly space velocity(GHSV) 10,000 hr~(-1) and 150°C with longterm stability. Compared with the other Co_3O_4 NAs catalysts, it had the highest abundance of surface-adsorbed oxygen species, excellent low-temperature reducibility and was rich in surface-active sites(Co~(3+)/Co~(2+)= 1.26).     

镍/铁二元金属对莠去津脱氯特性的影响

为了考察Ni/Fe二元金属对莠去津的催化还原特性,分别以Fe粉和Ni/Fe体系作为还原和催化剂,在酸性条件下对莠去津的脱氯特性进行比较,并讨论了pH值,Ni/Fe配比以及金属添加量等因素对莠去津脱氯效率的影响.结果表明:与Fe粉比较,Ni/Fe体系对莠去津具有很明显的催化脱氯特性.在pH=2时,1.22%(W/W)Ni/Fe体系30min对莠去津的脱氯效率大于90%,相同条件下用Fe粉还原时,90min脱氯效率仅为22.21%通过Fe粉和Ni/Fe表面形态的比较以及实验结果的分析,对Ni/Fe体系的催化还原脱氯机理进行了初步探讨.     

厄尔尼诺灾害的地球动力学解释以及与地质科学的联系

本文从地质力学的理论基础出发,详细地叙述了对厄尔尼诺这一大尺度气象灾害的机制所作的探讨。指出对于地球上任何大尺度的自然现象进行分析、探讨、研究时,都不应忽视地球自转的作用和影响。本文还将海气相互作用与构造体系进行了联系并对全世界地质学与环境生态学界普遍关注的全球海平面变化问题表述了自己的见解。     

Enhanced dechlorination of 2,4-dichlorophenol by recoverable Ni/Fe–Fe3O4 nanocomposites

Ni/Fe-Fe_3O_4 nanocomposites were synthesized for dechlorination of 2,4-dichlorophenol(2,4-DCP). The effects of the Ni content in Ni/Fe-Fe_3O_4 nanocomposites, solution pH, and common dissolved ions on the dechlorination efficiency were investigated, in addition to the reusability of the nanocomposites. The results showed that increasing content of Ni in Ni/Fe–Fe_3O_4 nanocomposites, from 1 to 5 wt.%, greatly increased the dechlorination efficiency; the Ni/Fe–Fe_3O_4 nanocomposites had much higher dechlorination efficiency than bare Ni/Fe nanoparticles. Ni content of 5 wt.% and initial p H below 6.0 was found to be the optimal conditions for the catalytic dechlorination of 2,4-DCP. Both 2,4-DCP and the intermediate product 2-chlorophenol(2-CP) were completely removed, and the concentration of the final product phenol was close to the theoretical phenol production from complete dechlorination of 20 mg/L of 2,4-DCP, after 3 hr reaction at initial p H value of 6.0,3 g/L Ni/Fe-Fe_3O_4 , 5 wt.% Ni content in the composite, and temperature of 22℃. 2,4-DCP dechlorination was enhanced by Cl-and inhibited by NO3-and SO_4~(2-). The nanocomposites were easily separated from the solution by an applied magnetic field. When the catalyst was reused, the removal efficiency of 2,4-DCP was almost 100% for the first seven uses, and gradually decreased to 75% in cycles 8–10. Therefore, the Ni/Fe–Fe_3O_4 nanocomposites can be considered as a potentially effective tool for remediation of pollution by 2,4-DCP.     

区域气象条件和减排对空气质量改善的贡献评估

区域气象条件和减排与空气质量的变化关系密切.区域污染天气的发生不只受人为排放的影响,其与气象条件也密切有关.我国地处全球的主要季风气候区,大气环流具有明显的季风气候变化特征,区域气象条件受年际气候变化影响显著.研究通过分析不同气候条件下京津冀地区、成渝地区、长三角和珠三角城市群2001～2018年主要气象要素及其污染天...