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Photocatalytic remediation ofγ-hexachlorocyclohexane contaminated soils using TiO_2 and montmorillonite composite photocatalyst

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Journal of Environmental Sciences 2007年第3期19卷 358-361页

作者： ZHAO Xu quan xie CHEN Shuo ZHAO Hui-min LIU Yu Department of Environmental Science and Technology Dalian University of Technology Dalian 116024 China State key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China.

TiO2 and montmorillonite composite photocatalysts were prepared and applied in degrading γ-hexachlorocyclohexane （γ-HCH） in soils. After being spiked with γ-HCH, soil samples loaded with the composite photocatalysts were exposed to UV-light irradiation. The results indicated that the photocatalytic activities of the composite photocatalysts varied with the content of TiO2 in the order of 10%〈70%〈50% 〈30%, Moreover, the photocatalytic activity of the composite photocatalysts with TiO2 content 30% was higher than that of the pure P25 with the same mass of TiO2. The strong adsorption capacity of the composite photocatalysts and quantum size effect may contribute to its increased photocatalytic activities. In addition, effect of dosage of composite photocatalysts and soil pH on γ-HCH photodegradation was investigated. Pentachlorocyclohexene, trichlorocyclohexene, and dichlorobenzene were detected as photodegradation intermediates, which were gradually degraded with the photodegradation evolution.

关键词： TiO2 montmorillonite γ-HCH soil surfaces composite photocatalysts

Fabrication of quantum-sized Cd S-coated Ti O2 nanotube array with efficient photoelectrochemical performance using modified successive ionic layer absorption and reaction(SILAR) method

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Science Bulletin 2015年第14期60卷 1281-1286页

作者： Na Lu Yan Su Jingyuan Li Hongtao Yu xie quan Key Laboratory of Industrial Ecology and Environmental Engineering Ministry of Education School of Environmental Science and Technology Dalian University of Technology Institute of Electrostatics and Special Power Dalian University of Technology Faculty of Chemical Environmental and Biological Science and Technology Dalian University of Technology

quantum-sized CdS-coated TiO2 nanotube array （Q-CdS-TiO2 NTA） was fabricated by the modified successive ionic layer absorption and reaction method. Scanning electron microscope and transmission electron microscope images showed the regular structure of TiO2 NTA, where quantum-sized CdS （diameter 〈10nm） deposited on both the inside and outside of TiO2 nanotube wall. Fabrication conditions including immersing cycles, calcination temperature and drying process were well optimized, and the Q-CdS-TiO2 NTA and its photoelectrochemical （PEC） properties were characterized by X-ray fluorescence spectrometer, UV-Vis diffuse reflectance spectra and photovoltage. Distinct increases in visible light absorption and photocurrent were observed as the immersing cycle was increased from 5 to 20 times. The additional drying process accelerated the CdS crystal growth rate, and thus, the fabrication time could be shortened accordingly. Calcination temperature influenced the PEC property of Q-CdS-TiO2 NTA deeply, and the optimized calcination temperature was found as 500 ℃. As the Q-CdS-TiO2 NTA was fabricated under such condition, the visible photocurrent density increased to 2.8 mA/cm and the photovoltage between 350 and 480 nm was enhanced by 2.33 times than that without calcination. This study is expected to optimize Q-CdS-TiO2 NTA fabrication conditions for the purpose of improving its PEC performance.

关键词： quantum-sized CdS TiO2 nanotubearray Photoelectrochemical property

Melting kinetics of bulk SiC using molecular dynamics simulation

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Science China(Physics,Mechanics & Astronomy) 2013年第9期56卷 1699-1704页

作者： YAN WanJun GAO TingHong GUO XiaoTian QIN YunXiang xie quan Institute of New Type Optoelectronic Materials and Technology College of ScienceGuizhou University Department of Physics and Electronic Science Anshun University

The melting kinetics of bulk SiC is studied by using classical molecular dynamics *** mean square displacement,diffusion coefficient,Lindemann index and non-Gaussian parameter are used to analyze the melt nucleation and macrokinetics in the melting *** occurs when the superheated crystal spontaneously generates many Lindemann particles in which they coalesce together to form melt nucleation inside the *** melting process is similar to the solidification process,but also experiences three processes such as nucleation,growth and *** melting process can be divided into premelting,accelerated melting and relaxation *** the sectional method can properly reflect the kinetic characteristics of the melting process.

关键词： melting kinetics molecular dynamics bulk SiC

Microwave assisted wet oxidation of p-nitrophenol

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Science China(Technological Sciences) 2005年第2期48卷 220-232页

作者： BO Longli CHEN Shuo quan xie LIU Xitao ZHAO Huimin School of Environmental and Biological Science and Technology Dalian University of TechnologyDalian 116024China

Aqueous solution of p-nitrophenol(PNP)was treated continuously by microwave assisted wet oxidation while flowing through a granular activated carbon(GAC)fixed *** was pre-adsorbed onto GAC prior to being put into the reactor so as to prevent PNP adsorption on GAC during microwave *** solutions with different initial concentration(218.6 mg/L and 1200 mg/L)were treated under conditions of microwave power 500 W,liquid flow 6.4 mL/min and air flow 40 mL/min or 60 mL/*** results indicated that the removal of PNP was higher than 90%and more than 65%PNP was ***,nitrobenzene,hydroquinone and benzoquinone occurred as course products during the operation process,which were degraded *** biodegradability of the outflow was improved greatly by microwave assisted wet oxidation.

关键词： p-nitrophenol granular activated carbon fixed bed microwave wet oxidation

An approximate analytical solution for transient gas flows in a vertically fractured well of finite fracture conductivity

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Petroleum Science 2022年第6期19卷 3059-3067页

作者： Yun-Hu Lu Kang-Ping Chen Yan Jin Hong-Da Li quan xie College of Petroleum Engineering China University of Petroleum(Beijing)Beijing102200China School for Engineering of Matter Transport and EnergyArizona State UniversityTempeAZ85287-6106USA Discipline of Petroleum Engineering WA School of Mines:MineralsEnergy and Chemical EngineeringCurtin University26 Dick Perry Avenue6151KensingtonWestern AustraliaAustralia

An analytical solution in physical variable space is presented for transient gas flows during constant-rate production from a vertically-fractured well in an infinite homogeneous reservoir with finite fracture *** solution is based on the short-time asymptotic solution and a new approximate transient elliptical flow solution,which covers transient flows from the bilinear flow regime to the pseudo-radial flow *** solution covers the well-known asymptotic solutions in both short-and long-time limits of bilinear and pseudo-radial *** analytical model provides a practical and reliable engineering tool to evaluate the fractured reservoir properties,which can be programmed using a spreadsheet.

关键词： Transient gas pressure Fractured well Analytical solution

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我国民爆物品爆炸事故统计分析及防范对策

爆破 2024年第1期41卷 202-209页

作者：张飞燕何鑫张念思孙金山谢全民河南理工大学安全科学与工程学院焦作454003 煤炭安全生产与清洁高效利用省部共建协同创新中心焦作454003 江汉大学省部共建精细爆破国家重点实验室武汉430056 江汉大学爆破工程湖北省重点实验室武汉430056

为分析我国民爆物品爆炸事故一般性规律与事故原因,对2006—2023年全国民爆物品爆炸事故的发生时间、地区分布、事故等级等维度进行事故统计与分析,使用层次分析法构建了包含人、机、环、制度4个一级指标和安全意识、技术培训、监管力... 详细信息

为分析我国民爆物品爆炸事故一般性规律与事故原因,对2006—2023年全国民爆物品爆炸事故的发生时间、地区分布、事故等级等维度进行事故统计与分析,使用层次分析法构建了包含人、机、环、制度4个一级指标和安全意识、技术培训、监管力度、安全教育、标准化作业、生产设备、生产工艺、天气气候、仓储条件、安全管理体制、应急管理制度共11个二级指标的层次结构模型,通过分析得到各指标权重进而对爆炸事故影响因素做出重要性排序。研究结果表明:爆炸事故发生次数逐年降低,安全形势转好,时间上集中于每年的第2、3季度,空间上以“南北高低交错”特征分布于各省份,事故等级中一般事故、较大事故占据主导地位;基于层次分析法得知一级指标中人是造成事故的最主要因素,二级指标中标准化作业、生产工艺、监管力度和安全管理体制是比较重要的几项因素,最后针对事故影响因素重要度提出了严格标准化作业、增加安全投入、加强监管力度和完善安全管理体制的预防措施。

关键词：民爆物品爆炸事故事故统计影响因素分析层次分析法防范对策

Enhanced photodegradation of phenolic compounds by adding TiO_2 to soil in a rotary reactor

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Journal of Environmental Sciences 2006年第6期18卷 1107-1112页

作者： WANG Jing-xian CHEN Shuo quan xie ZHAO Hui-min ZHAO Ya-zhi School of Environmental and Biological Science and Technology Dalian University of Technology Key Laboratory of Industrial Ecology and Environmental Engineering Ministry of EducationDalian 116023 China

Photodegradation ofpentachlorophenol （PCP） and p-nitrophenol （PNP） in soil was carried out in a designed rotary reactor, which can provide the soil particles with continually uniform irradiation, and on a series of thin soil layers. TiO2, as a kind of environmental friendly photocatalyst, was introduced to the soil to enhance the processes. Compared with that on the soil layers, photodegradation of PCP at initial concentration of 60 mg/kg was improved dramatically in the rotary reactor no matter whether TiO2 was added, with an increase of 3.0 times in the apparent first-order rate constants. The addition of 1 wt% TiO2 furthered the improvement by 1.4 times. Without addition of TiO2, PNP （initial concentration of 60 mg/kg） photodegradation rate in the rotary reactor was similar to that on the soil layers. When 1 wt% additional TiO2 was added, PNP photodegradation was enhanced obviously, and the enhancement in the rotary reactor was 2 times of that on the soil layers, which may be attributed to the higher frequency of the contact between PNP on soil particles and the photocatalyst. The effect of soil pH and initial concentrations of the target compounds on the photodegradation in the rotary reactor was investigated. The order of the degradation rate at different soil pH was relative to the aggregation of soil particles during mixing in the rotary reactor. Photodegradation of PCP and PNP at different initial concentrations showed that addition of TiO2 to enhance the photodegradation was more suitable for contaminated soil with higher concentration of PCP, while was effective for contaminated soil at each PNP concentration tested in our study.

关键词： TiO2 photodegradation phenolic compounds soil remediation

Preparation and characteri-zation of aligned carbon nanotubes coated with titania nanoparticles

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Chinese Science Bulletin 2006年第18期51卷 2294-2296页

作者： YU Hongtao ZHAO Huimin quan xie CHEN Shuo Key Laboratory of Industrial Ecology and Environmental Engineering Ministry of Education School of Environmental and Biological Science and Technology Dalian University of Technology Dalian 116024 China

Well-aligned carbon nanotubes coated with titania (TiO2) were prepared by atmospheric pressure chemical vapor deposition (APCVD),and the sequential experiments including carbon nano- tubes preparation,air-oxidation purification and tita- nia nanoparticles coating were performed at different temperatures in the same reactor. Scanning electron microscopy (SEM),transmission electron microscope (TEM),X-ray diffraction patterns (XRD),and energy- dispersive X-ray spectra (EDX) demonstrated the well-aligned nanotubes and TiO2 nanoparticles in close proximity and the average diameter of TiO2 nanoparticles was 11.5 nm.

关键词：化学气相淀积碳纳米管涂层 TiO2 APCVD

过渡金属掺杂的g-GaN吸附Cl_(2)和CO气体分子的第一性原理研究

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无机化学学报 2024年第6期40卷 1189-1200页

作者：田双林高廷红刘玉涛陈茜谢泉肖清泉梁永超贵州大学大数据与信息工程学院新型光电子材料与技术研究所贵阳550025

基于密度泛函理论的第一性原理计算,系统研究了类石墨烯氮化镓(g-GaN)和掺杂过渡金属原子(TM)的g-GaN对Cl_(2)和CO气体分子的吸附行为。结果表明,Cl_(2)和CO在本征g-GaN上的吸附均为物理吸附,2个体系的吸附能均为正值,表明体系不稳定。... 详细信息

基于密度泛函理论的第一性原理计算,系统研究了类石墨烯氮化镓(g-GaN)和掺杂过渡金属原子(TM)的g-GaN对Cl_(2)和CO气体分子的吸附行为。结果表明,Cl_(2)和CO在本征g-GaN上的吸附均为物理吸附,2个体系的吸附能均为正值,表明体系不稳定。相反,Cl_(2)和CO在Fe和Co掺杂的g-GaN上吸附时的吸附能为负值,且吸附能较小,表明吸附体系稳定。通过分析态密度、电荷密度差和能带结构等性质,可以得出结论:过渡金属原子的引入能有效增强气体分子与g-GaN之间的相互作用。

关键词：气体传感类石墨烯GaN 吸附过渡金属掺杂