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Preparation and properties of Nd,Yb:GGG polycrystalline nanopowders

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Journal of Advanced Ceramics 2012年第4期1卷 296-300页

作者： Yanmin DONG Jing SUN Wensheng YU Weihang LI Fei TENG School of Chemistry and environmental Engineering Changchun University of Science and TechnologyChangchun 130022China

Gadolinium gallium garnet(GGG)polycrystalline powders doped with Nd,Yb were prepared by co-precipitation *** structure,phase and properties of powders were characterized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FTIR),scanning electron microscope(SEM),energy dispersive X-ray spectroscopy(EDS)and fluorescence *** analysis indicated that the crystallization of Nd,Yb:GGG powders occur at 900􀄇.SEM analysis showed that the morphology of the powders was irregular and the average radius is 68.74 *** analysis manifested that pure Nd,Yb:GGG powders were formed at 900􀄇.The fluorescence spectrum revealed that the most strong emission of Nd,Yb:GGG powders was 1030 nm,which was attributed to 2F5/2􀄺2F7/2 of Yb3+.The possible formation mechanism of Nd,Yb:GGG powders were preliminarily discussed.

关键词： Nd,Yb:GGG co-precipitation method fluorescence

Analysis of the origin of peak aerosol optical depth in springtime over the Gulf of Tonkin

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Journal of environmental sciences 2016年第2期28卷 129-137页

作者： Xiaoli Shan Jun Xu Yixue Li Feng Han Xiaohui Du Jingying Mao Yunbo Chen Youjiang He Fan Meng Xuezhi Dai College of Resources and Environment Shandong Agricultural University Taian 271000 China State Key Laboratory of environmental Criteria and Risk Assessment Chinese Research Academy of Environmental SciencesBeijing 100012 China College of environmental science and Engineering Taiyuan University of Technology Taiyuan 030024 China College of Geography and Environment Shandong Normal University Jinan 250014 China environmental Protection Research institute of Guangxi Nanning 530022 China

By aggregating MODIS（moderate-resolution imaging spectroradiometer） AOD（aerosol optical depth） and OMI（ozone monitoring instrument） UVAI（ultra violet aerosol index）datasets over 2010–2014, it was found that peak aerosol loading in seasonal variation occurred annually in spring over the Gulf of Tonkin（17–23°N, 105–110°E）. The vertical structure of the aerosol extinction coefficient retrieved from the spaceborne lidar CALIOP（cloud-aerosol lidar with orthogonal polarization） showed that the springtime peak AOD could be attributed to an abrupt increase in aerosol loading between altitudes of 2 and 5 *** contrast, aerosol loading in the low atmosphere（below 1 km） was only half of that in winter. Wind fields in the low and high atmosphere exhibited opposite transportation patterns in spring over the Gulf of Tonkin, implying different sources for each level. By comparing the emission inventory of anthropogenic sources with biomass burning, and analyzing the seasonal variation of the vertical structure of aerosols over the Northern Indo-China Peninsula（NIC）, it was concluded that biomass burning emissions contributed to high aerosol loading in spring. The relatively high topography and the high surface temperature in spring made planetary boundary layer height greater than 3 km over NIC. In addition, small-scale cumulus convection frequently occurred, facilitating pollutant rising to over 3 km, which was a height favoring long-range transport. Thus, pollutants emitted from biomass burning over NIC in spring were raised to the high atmosphere, then experienced long-range transport, leading to the increase in aerosol loading at high altitudes over the Gulf of Tonkin during spring.

关键词： Gulf of Tonkin Aerosol optical depth Aerosol vertical structure Biomass burning Transportation

Ventilation of indoor formaldehyde and estimation of its emission and air exchange rate

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Journal of Harbin institute of Technology(New Series) 2007年第1期14卷 41-44页

作者：王琨赵庆良李文朴李玉华 School of Municipal and environmental Engineering Harbin Institute of Technology Tianjin institute of Urban Construction

Residents living in the cold areas such as Harbin generally experience a residence time of approximately 6 months in chilly winter without frequent natural ventilation. To find out the influence of a short period of ventilation on the indoor formaldehyde concentration inside a new building, an investigation was conducted for the instance of twice ventilation in a day through window opening. The results showed that the initial concentration of formaldehyde was 3.53 -8. 48 times as high as the concentration after 10 min ventilation. After closing the window, the indoor formaldehyde concentration increased with time and followed an exponential equation of C = C0 exp（ - b ＊ t）＋（ a ＋ Cu, ） [ 1 - exp（ - b ＊ t） ] with correlation coefficient （ R^2 ） of 0. 945 - 0. 999, based on the statistical analysis of 14 groups of measurement data. The developed equation can be used to estimate the emission rate of indoor formaldehyde sources and the air exchange rate of the test room simultaneously.

关键词： indoor air formaldehyde ventilation air exchange

The colorful chemistry of nanoscale zero-valent iron(nZVI)

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Journal of environmental sciences 2018年第5期30卷 1-3页

作者： Yilong Hua Jing Liu Tianhang Gu Wei Wang Wei-xian Zhang State Key Laboratory of Pollution Control and Resource Reuse School of Environmental Science and Engineering Tongji University School of Chemical science and Engineering Tongji University

Nanoscale zero-valent iron （nZVI） possesses unique chemistry and capability for the separation and transformation of a growing number of environmental contaminants. A nZVI particle consists of two nanoscale components, an iron （oxyhydr）oxides shell and a metallic iron core. This classical ＂core-shell＂ structure offers nZVI with unique and multifaceted reactivity of sorption, complexation, reduction and precipita- tion due to its strong small particle size for engineering deployment, large surface area, abundant reactive sites and electron-donating capacity for enhanced chemical activity. For over two decades, research has been steadily expanding our understanding on the reaction mechanisms and engineering performance of nZVI for soil and groundwater remediation, and more recently for wastewater treatment.

关键词： Nanoscale zero-valent iron (nZVI) environmental nanotechnology Dyes and pigments Wastewater treatment Spherical aberration-corrected scan-ning transmission electron micros-copy (Cs-STEM)

Optimization of CHARMM force field parameters for the chalcone fragment

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science China Chemistry 2012年第12期55卷 2580-2586页

作者： ZHANG Hui YAO Yuan QI XiaoLi LI ZeSheng College of Chemical and environmental Engineering Harbin University of Science and TechnologyHarbin 150080China Academy of Fundamental and Interdisciplinary sciences Department of Chemistry Harbin institute of Technology Harbin 150080 China Key Laboratory of Cluster science of Ministry of Education School of Chemistly Beijing Institute of Technology Beijing 100081China

In this work,we developed the CHARMM all-atom force field parameters for the nonstandard biological residue chalcone,followed by the standard protocol for the CHARMM27 force field *** data were generated via ab initio calculations at the MP2/6-31G* and HF/6-31G* *** reference data included interaction energies between water and the model compound F(a fragment of chalcone).Bond,angle,and torsion parameters were derived from the ab initio calculations and renormalized to maintain compatibility with the existing CHARMM27 parameters of standard *** optimized CHARMM parameters perform well in reproducing the target *** expect that the extension of the CHARMM27 force field parameters for chalcone will facilitate the molecular simulation studies of the reaction mechanism of intramolecular cyclization of chalcone catalyzed by chalcone isomerase.

关键词： CHARMM force field parameters chalcone

Transcriptomic Analysis of Aflatoxin B1-Regulated Genes in Rat Hepatic Epithelial Cells

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Transactions of Tianjin University 2014年第6期20卷 451-457页

作者： Yang Liu Ji Jing Li Guanghui Li Junwen Chen Zhaoli Wang Haiyong School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China School of environmental science and Technology Tianjin UniversityTianjin 300072China Department of Chemistry Tangshan Normal UniversityTangshan 063000China institute of Hygiene and environmental Medicine Academy of Military Medical ScienceTianjin 300050China

Aflatoxins are the most popular hepatotoxicants. Chronic exposure to aflatoxins leads to a wide variety ofliver diseases, such as hepatocellular carcinoma. In this study, we analyzed the genome wide expression profiles ofaflatoxin B1-induced rat hepatic epithelial cells. The expression of 325, 184 and 199 special genes was altered whenexposed to 0.03, 0.1 and 0.2 μmol/L aflatoxin B1 respectively, and 239 genes were commonly expressed. After thefunctional analysis on these dose-special genes, we determined several key pathways related to hepatotoxicity, such asTGF-beta signaling pathway, tight junction, adherens junction, the regulation of actin cytoskeleton, ErbB signalingpathway, p53 signaling pathway, pathways in cancer and axon guidance. Common genes were mainly associated withfocal adhesion, ECM-receptor interaction, and cell adhesion molecules. Gene ontology annotations showed a goodconcordance with these pathways. The quantitative real-time polymerase chain reaction（PCR） analysis of selectedgenes showed similar patterns in microarrays. The toxicogenomic study provides a better understanding of molecularmechanisms of aflatoxins.

关键词： aflatoxin microarray gene ontology Kyoto encyclopedia of genes and genomes(KEGG) pathway hepatotoxicity

In-situ growth of CoNi bimetal anchored on carbon nanoparticle/nanotube hybrid for boosting rechargeable Zn-air battery

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Journal of Energy Chemistry 2022年第3期31卷 348-355,I0010页

作者： Jun Li Yongxia Wang Zhengyu Yin Rui He Yihao Wang Jinli Qiao State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Environmental Science and EngineeringDonghua UniversityShanghai 201620China Shanghai institute of Pollution Control and Ecological Security Shanghai 200092China

Exploring highly efficient non-precious metal based catalysts for bifunctional oxygen electrode is crucial for rechargeable metal-air *** this study,with MOFs as precursors,a facile coprecipitation method is designed to realize in-situ growth of the CoNi anchored carbon nanoparticle/nanotube(CoNi/N-CNN)hybrid,which can achieve the simultaneous maximum exposure of both oxygen evolution reaction(OER)and oxygen reduction reaction(ORR)active *** from the unique structure,the CoNi/N-CNN catalyst exhibits excellent electrocatalytic performance for ORR(E_(onset)=1.183 V,E_(1/2)=0.819 V)and a low operating voltage of 1.718 V at 10 mA cm^(−2)(Ej=10)for ***,the home-made rechargeable Zn-air battery with CoNi/N-CNN delivers a high discharge power density up to 209 mW cm^(−2),and an outstanding charge–discharge cycling *** boosted bifunctional electrocatalytic activity can be ascribed to the strong coupling effect between Co/Ni center sites and defect-rich N-anchored carbon featured with porous and nanotube structure,which can introduce uniformly dispersed active sites,tailored electronic configuration,superb conductivity and convenient charge transfer *** hybrid non-precious bimetal based electrocatalyst provides the possibility to develop the low-cost and high-efficient ORR/OER bifunctional electrocatalysts in rechargeable metal-air battery.

关键词： Co Ni/N-CNN Bifunctional electrocatalyst Oxygen electrode Rechargeable Zn-air battery

Research on mine dustfall agents based on the mechanism of wetting and coagulation

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International Journal of Minerals,Metallurgy and Materials 2014年第3期21卷 205-209页

作者： Jing Yang Dan-dan Liu Bing-jie Liu Min-min He Ying-feng Wang College of Chemical and environmental Engineering Shandong University of Science and Technology Key Laboratories of Coal Mine Disaster Prevention and Control Shandong University of Science and Technology

Mine dust is classified as one of five natural coal mining disasters because it can harm the health of miners and poses a serious threat to the safety of the coal mine. Therefore, preparation of an effective dust suppression agent is highly desired. To improve the capture efficiency of fine dust, this study examines the dust suppression effects of various combinations of wetting agents, additives, and coagulation agents by using the optimum seeking method to reduce mine dust, particularly respirable particles. The optimal formula is shown to contain 10wt% fatty alcohol polyoxyethylene ether（JFC）, 4.96wt% cationic polyacrylamide, and 4wt% calcium chloride. The dust suppression effect can be achieved at 96.1% in 5 min by using the optimal formula.

关键词： mine dust dust abatement wetting coagulation surface tension contact angle

Gravimetric analysis for PM_(2.5) mass concentration based on year-round monitoring at an urban site in Beijing

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Journal of environmental sciences 2016年第2期28卷 154-160页

作者： Yanli Wang Wen Yang Bin Han Wenjie Zhang Mindong Chen Zhipeng Bai State Key Laboratory of environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Nanjing University of Information Science & Technology

Daily PM_（2.5）（particulate matter with an aerodynamic diameter of below 2.5 μm） mass concentrations were measured by gravimetric analysis in Chinese Research Academy of environmental sciences（CRAES）, in the northern part of the Beijing urban area, from December 2013 to April 2015. Two pairs of Teflon（T1/T2） and Quartz（Q1/Q2） samples were obtained, for a total number of 1352 valid filters. Results showed elevated pollution in Beijing,with an annual mean PM_（2.5）mass concentration of 102 μg/m^3. According to the calculated PM_（2.5）mass concentration, 50% of our sampling days were acceptable（PM_（2.5）〈 75 μg/m^3）, 30% had slight/medium pollution（75–150 μg/m^3）, and 7% had severe pollution（〉 250 μg/m^3）. Sampling interruption occurred frequently for the Teflon filter group（75%） in severe pollution periods,resulting in important data being missing. Further analysis showed that high PM_（2.5）combined with high relative humidity（RH） gave rise to the interruptions. The seasonal variation of PM_（2.5）was presented, with higher monthly average mass concentrations in winter（peak value in February, 422 μg/m^3）, and lower in summer（7 μg/m^3 in June）. From May to August, the typical summer period, least severe pollution events were observed, with high precipitation levels accelerating the process of wet deposition to remove PM_（2.5）. The case of February presented the most serious pollution, with monthly averaged PM_（2.5）of 181 μg/m^3 and 32% of days with severe pollution. The abundance of PM_（2.5）in winter could be related to increased coal consumption for heating needs.

关键词： PM_(2.5) Gravimetric analysis Sampling interruption Pollution level Relative humidity(RH) Seasonal variation