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High time resolution observation and statistical analysis of atmospheric light extinction properties and the chemical speciation of fine particulates

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Science china Chemistry 2010年第8期53卷 1801-1808页

作者： YAO TingTing1,HUANG XiaoFeng1,HE LingYan1,HU Min2,SUN TianLe1,XUE Lian1,LIN Yun1,ZENG LiWu1 & ZHANG YuanHang2 1Key Laboratory for Urban Habitat environmental Science and technology,school of environment and Energy,Peking university Shenzhen Graduate school,Shenzhen 518055,china 2State Key Joint Laboratory of environmental Simulation and Pollution Control College of environmental Sciences and engineering,Peking university,beijing 100871,china 1. Key Laboratory for Urban Habitat environmental Science and technology School of Environment and Energy Peking University Shenzhen Graduate School Shenzhen 518055 China2. State Key Joint Laboratory of Environmental Simulation and Pollution Control College of environmental Sciences and engineering Peking University Beijing 100871 China

In recent years,the visibility deterioration caused by regional fine particulate pollution becomes one of the crucial air pollution problems in the urban areas of our *** rapid variation of visibility and fine particulates make it difficult to estimate the relationship between them precisely and accurately unless high time resolution observation data can be *** study aims to fill this gap in the field of atmospheric science by establishing a formula using multiple linear *** fitting goodness (R2=0.913,n=3167) was obtained using 10 min average of high-resolution real-time light scattering coefficients,light absorption coefficients,main chemical speciation concentration in PM1 and some meteorological parameters from 17 Jan to 16 Feb,*** shows that the average light extinction coefficient during the observation in the winter of Shenzhen was measured to be 290 ± 183 Mm?1,consisting of 72% of light scattering and 21% of *** terms of the percentage contribution of PM1 chemical species to the total light extinction,the organic matter was estimated to be most with an average of 45%,followed by ammonium sulfate with an average of 24%.The contributions of black carbon and ammonium nitrate were 17% and 12%,***,the diurnal variation of light extinction was investigated as well in this study.

关键词： light extinction PM1 chemical speciation high time resolution multiple linear regressions

Vanadium recovery from clay vanadium mineral using an acid leaching method

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Rare Metals 2008年第2期27卷 116-120页

作者： LI Haoran FENG Yali LIANG Jianglong LUO Xiaobing DU Zhuwei State Key Laboratory of Biochemical engineering Institute of Process Engineering Chinese Academy of Sciences Beijing 100080 China Civil and environmental engineering school University of Science and Technology Beijing Beijing 100083 China

A technique including direct acid leaching, vanadium precipitation with alkaline, sodium hydroxide releaching, impurity removing by adjusting pH value, precipitation vanadium with ammonium chloride, and vanadium pentoxide by roasting steps was proposed according to the characteristic of Xichuan clay vanadium mineral. The factors influencing leaching vanadium such as temperature and the concentration of sulfuric acid were investigated and optimized. The experimental results indicate that the extract ratios of V205 can reach 94% and 92% at a sodium chlorate ratio of 3% and a manganese dioxide ratio of 3%, respectivdy. A completely chemical precipitation method was adopted to decontaminate and enrich the vanadium in the acid leaching solution. The X-ray diffraction （XRD） pattern and the purity analysis of vanadium pentoxide indicate that the purity of final vanadium pentoxide can reach 99% and meet the standard specifications. The total recovery can reach about 75%. The technique has the characteristics of simplicity, less investment, and more environment safety as compared with the traditional salt roasting method.

关键词： clay vanadium mineral vanadium extraction acid leaching vanadium pentoxide

Synthesis,characterization,structures and magnetic property of chiral oxalate-bridged dicopper(Ⅱ) complexes

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Science china Chemistry 2010年第6期53卷 1255-1260页

作者： WU Ling1,WANG Jun2,ZHU CaiFei1,LIN YiJi1,CHEN LeiQi1,FAN Jun2 & ZHANG Hui1 1State Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry,College of Chemistry and chemical engineering,Xiamen university,Xiamen 361005,china 2school of Chemistry and environment,South china Normal university,Guangzhou 510006,china 1. State Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical Engineering Xiamen University Xiamen 361005 China2. School of Chemistry and Environment South China Normal University Guangzhou 510006 China

The oxalato-bridged dicopper(II) complexes [Cu2(μ-ox)(LRR)2(H2O)2(ClO4)2] (1),[Cu2(μ-ox)(LRR)2(CH3COCH3)2(ClO4)2](1a),[Cu2(μ-ox)(LSS)2(H2O)2(ClO4)2] (2) and [Cu2(μ-ox)(LRR)(LSS)2(CH3COCH3)2(ClO4)2] (3) [LRR = (8R,10R)-(-)-[4,5]-pineno2,2′-bipyridine,LSS = (8S,10S)-(+)-[4,5]-pineno-2,2′-bipyridine;ox2= oxalate] were first prepared.A possible mechanism for the formation of the chial dicopper(II) complexes was *** on elemental analysis,conductance measurement,UV-Vis spectra,CD spectra and X-ray single-crystal diffraction,the oxalato-bridged structures of 1 and 2 were deduced to adopt two Cu(II) ions and the bridged oxalate lying in the nearly same *** crystal structures of 1a and 3 reveal that the coordination geometry around each Cu(II) ion is an elongated and distorted octahedron and two axial solvent molecules and two perchlorate ions are anti to each other respectively in both binuclear *** solution CD spectra of 1 and 2 in the visible d-d range show very weak Cotton effects with peaks at 588 and 779 nm,which are approximately of mirror image,suggesting the optical activities may be derived from the vicinal effects of the chiragenic centers at the pinene group of LRR and LSS,*** 1 has been characterized by variable-temperature magnetic susceptibility and the data was least-square fitted to the Blenaey-Bowers *** exchange integral J was found to be -338.41(4) cm-1,indicating a strong antiferromagnetic interaction between two copper(II) ions.

关键词： dicopper(II) complex chiral bipyridine μ-oxalate bridge crystal structure CD spectroscopy magnetic property

Risk Control of Liquid Chlorine Leak in Wastewater Treatment Plant Based on QRA

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Risk Control of Liquid Chlorine Leak in Wastewater Treatment...

2010(沈阳)国际安全科学与技术学术研讨会

作者： ZHANG Sheng-zhu~1,WU Zong-zhi~2,KANG Rong-xue~2,SANG Hai-quan~2,GU Hai-bo~2,LIU Ning~3 (1.Faculty of Resources and Safety engineering,china university of mining and technology(beijing),beijing 100083.china 2.china Academy of Safety Science and technology,beijing 100012,china 3.Civil and environment engineering school,university of Science and technology beijing 100083.china)

＜正＞The bulk storage of liquid chlorine meets the need of disinfection but also poses a considerable risk to the residents *** on the risk analysis of chlorine leak,and through the study of chlorine leak mode,leak source strength and the consequences of accidents,the model of accident consequences of chlorine leak was *** was analyzed by quantitative method and the acceptable standards of individual and social risk were *** quantitative risk calculations are performed in a wastewater treatment plant,and the individual risk contour and social risk curve are *** respect of the high-risk areas,risk control measures are proposed.

关键词： wastewater treatment plant chlorine leak quantitative risk assessment risk control

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反渗透技术用于高矿化度矿井水处理的研究

水处理技术 2009年第10期35卷 82-85页

作者：杨慧敏何绪文何咏中国矿业大学化学与环境工程学院北京100083

采用反渗透技术对高矿化度矿井水进行处理,考察了CPA(芳香族聚酰胺)膜对矿井水中各种离子的去除效果。试验结果表明:系统运行24d,对矿井水的处理效果显著,Ca2+、Cl-、SO42-、Mg2+各离子的平均去除率可分别达到98%、94%、98%、95%以上,... 详细信息

采用反渗透技术对高矿化度矿井水进行处理,考察了CPA(芳香族聚酰胺)膜对矿井水中各种离子的去除效果。试验结果表明:系统运行24d,对矿井水的处理效果显著,Ca2+、Cl-、SO42-、Mg2+各离子的平均去除率可分别达到98%、94%、98%、95%以上,系统出水水质稳定,出水达到国家饮用水标准;并根据静态清洗反渗透(RO)污染膜的分析结果,总结出反渗透膜的污染特征,最终优选出先碱洗后酸洗的膜清洗方案。

关键词：反渗透矿井水高矿化度反渗透膜

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植物对硅的吸收转运机制研究进展

生物化学与生物物理进展 2011年第5期38卷 400-407页

作者：张玉秀刘金光柴团耀金玲中国矿业大学(北京)化学与环境工程学院北京100083 中国科学院研究生院生命科学学院北京100049

硅(Si)能缓解生物与非生物胁迫对植物的毒害作用,Si的吸收转运是由Si转运蛋白介导的.最近,多个Si转运蛋白(Lsi)基因相继在水稻、大麦和玉米中被克隆出来,并在Si的吸收转运机制方面取得了很大进展.水稻OsLsi在根组织中呈极性分布,OsLsi1... 详细信息

硅(Si)能缓解生物与非生物胁迫对植物的毒害作用,Si的吸收转运是由Si转运蛋白介导的.最近,多个Si转运蛋白(Lsi)基因相继在水稻、大麦和玉米中被克隆出来,并在Si的吸收转运机制方面取得了很大进展.水稻OsLsi在根组织中呈极性分布,OsLsi1定位在根外皮层和内皮层凯氏带细胞外侧质膜,负责将外部溶液中的单硅酸转运到皮层细胞内.OsLsi2定位在凯氏带细胞内侧质膜,在外皮层中负责将Si输出到通气组织质外体中,在内皮层与OsLsi1协同作用将Si转运到中柱中.导管中的Si通过蒸腾流转运到地上部,再由定位在叶鞘和叶片木质部薄壁细胞靠近导管一侧的OsLsi6负责木质部Si的卸载和分配.在大麦和玉米中,ZmLsi1/HvLsi1定位在根表皮和皮层细胞外侧质膜负责Si的吸收,然后Si通过共质体途径被转运到内皮层凯氏带细胞中,再由ZmLsi2/HvLsi2输出转运到中柱中.ZmLsi6在细胞中的定位和活性与OsLsi6相似,推测其可能具有类似的功能,但大麦Lsi6至今未见报道.所以,Si转运机制仍需要进一步研究.

关键词：硅转运蛋白机制

Copper-Ti_3SiC_2 composite powder prepared by electroless plating under ultrasonic environment

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Rare Metals 2007年第4期26卷 359-364页

作者： ZHANG Zhongbao XU Shaofan school of Materials Science and engineering Hefei University of Technology Hefei 230009 China

In this article, a new type of Cu-Ti3SiC2 composite powder prepared using the electroless plating technique was introduced. The initial Ti3SiC2 particles are 11 μm in diameter on an average. The Cu plating was carried out at middle temperature （62-65℃） with the application of ultrasonic agitation. The copper deposition rate was determined by measuring the weight gain of the powder after plating. It has been found that the pretreatment of Ti3SiC2 powder is very important to obtain copper nanoparticles on the surface of Ti3SiC2 The optimum procedure before plating aimed to add activated sites and the adjustment of the traditional composition of the electroless copper plating bath could decelerate the copper deposition rate to 0.8 gm/h. X-ray diffraction （XRD） indicates that the chemical composition of the plating layer is copper. SEM images show that the surface of the Ti3SiC2 particles is successfully coated with continuous copper layer. The wetting property between the copper matrix and Ti3SiC2 can be improved so as to increase the interfacial strength.

关键词： composites electroless plating Ti3SiC2 ultrasonic interfacial strength

Effects of magnetic field on fluidization properties of magnetic pearls

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Particuology 2007年第Z1期 151-155页

作者： Maoming Fana,b, Zhenfu Luob, Yuemin Zhaob, Qingru Chenb, Daniel Taoa, Xiuxiang Taob, Zhenqiang Chenb a Department of mining engineering, university of Kentucky, 230 mining and Mineral Resources Building, Lexington, KY 40506, USA b school of chemical engineering and technology, china university of mining and technology, Xuzhou 221008, Jiangsu, china

An experimental study of the influence of external magnetic field on the fluidization behavior of magnetic pearls was carried out. Magnetic pearls are a magnetic form of iron oxide that mainly consists of Fe2O3 which are recovered from a high-volume power plant fly ash from pulverized coal combustion. Due to its abundance, low price and particular physical and chemical properties, magnetic pearls can be used as a heavy medium for minerals or solid waste dry separation based on density difference. This paper introduces the properties of magnetic pearls and compares the performance of magnetic pearls fluidised bed operation with or without an external magnetic field. Experimental results show that an external magnetic field significantly improves the fluidization performance of magnetic pearls such as uniformity and stability.

关键词： Magnetic pearls Magnetic field Fluidization properties Gravity separation

水煤浆添加剂与煤之间的相互作用规律研究 Ⅰ.复合煤颗粒间的相互作用对水煤浆流变性的影响

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燃料化学学报 2003年第6期31卷 519-524页

作者：朱书全邹立壮黄波崔广文王奇中国矿业大(北京)化学与环境工程学院北京100083

使用12种不同分散剂对14种不同变质程度的煤进行了成浆性实验,分析了182个水煤浆(CWS)样品的流变性。结果表明,低变质程度和高灰煤浆多呈屈服假塑性,煤的性质起主导作用;变质程度高且灰分较低煤浆的流变性,主要依赖于分散剂的结构与性质... 详细信息

使用12种不同分散剂对14种不同变质程度的煤进行了成浆性实验,分析了182个水煤浆(CWS)样品的流变性。结果表明,低变质程度和高灰煤浆多呈屈服假塑性,煤的性质起主导作用;变质程度高且灰分较低煤浆的流变性,主要依赖于分散剂的结构与性质;分子结构单元立体空间效应大,疏水基团与亲水基团呈立体间隔分布的分散剂,易形成屈服假塑性CWS;分子线度长,亲水基团与疏水基团呈线性间隔分布的分散剂,易形成胀塑性CWS。复合煤粒间的相互作用方式是决定CWS流变特性的关键。

关键词：水煤浆添加剂煤分散剂流变特性复合煤粒相互作用