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Microstructures and speciation of radionuclides in natural environment studied by advanced spectroscopy and theoretical calculation

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Science China Chemistry 2017年第9期60卷 1149-1152页

作者： Xiangxue wang Shujun Yu Zhongshan Chen Yushan Zhao Jie Jin xiangke wang School of Environment and Chemical Engineering North China Electric Power UniversityBeijing 102206China

The environmental behavior of radionuclides is mainly dependent on their speciation and microstructures at solid *** speciation and microstructures of radionuclides at molecular level can be achieved from advanced spectroscopy techniques and theoretical *** this perspective,we give a brief introduction of the advanced X-ray absorption fine structure(XAFS) technique and theoretical calculation in the analysis of the speciation and microstructures of radionuclides in the natural environment,which is crucial to evaluate the physicochemical behavior of radionuclides in the environment.

关键词：中国科学化学英文版

HTDcr:a job execution framework for high-throughput computing on supercomputers

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Science China(Information Sciences) 2024年第1期67卷 69-85页

作者： Jiazhi JIANG Dan HUANG Hu CHEN Yutong LU xiangke LIAO School of Computer Science and Engineering Sun Yat-sen University School of Software Engineering South China University of Technology

High-throughput computing(HTC) is a computing paradigm that aims to accomplish jobs by easily breaking them into smaller,independent ***,it requires a large amount of computing power for a long *** existing HTC frameworks are job-oriented without support for coscheduling with hardware architecture and task-level ***,most of the frameworks reach a limited scale,and their usability needs further ***,we present HTDcr,a job execution framework for the HTC on *** study aims to improve the throughput,task dispatching,and usability of the *** detail,the throughput optimizations include a sophisticated designed task management system,a hierarchical scheduler,and the co-optimization of the task-scheduling strategy with the application and hardware *** optimizations for usability include a programable execution workflow,mechanisms for more robust and reliable service qualities,and a fine-grained resource allocation system for the colocation of multiple *** to our evaluations,HTDcr can achieve outstanding scalability and high throughput on large-scale clusters for the HTC *** evaluate HTDcr with several microbenchmarks and real-world applications on Tianhe-2 and Sunway TaihuLight to demonstrate its effects on existing design *** instance,the task scheduling for two real-world applications integrated with the application and hardware characteristics achieves 1.7× and 1.9× speedups over the basic task-scheduling strategy.

关键词： high-throughput computing supercomputer task scheduling middleware password guessing

Simultaneous removal of uranium and humic acid by cyclodextrin modified graphene oxide nanosheets

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Science China Chemistry 2014年第9期57卷 1291-1299页

作者： SONG WenCheng SHAO DaDong LU SongSheng wang xiangke School of Nuclear Science and Technology University of Science and Technology of China Institute of Plasma Physics Chinese Academy of Sciences New Star Institute of Applied Technology

Cyclodextrin-modified graphene oxide nanosheets(denoted as CD/GO) were synthesized by an in-situ polymerization method and characterized by as well as Fourier transform-infrared spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy and potentiometric acid-base titration. The characterization results indicated that CD was successfully grafted onto GO surfaces by forming a chemical bond. Mutual effects on the simultaneous removal of hexavalent uranium and humic acid by CD/GO from aqueous solution were investigated. The results indicated that U(VI) and humic acid(HA) sorption on CD/GO were greatly affected by pH and ionic strength. The presence of HA enhanced U(VI) sorption at low pH and reduced U(VI) sorption at high pH, whereas the presence of U(VI) enhanced HA sorption. The surface adsorbed HA acted as a "bridge" between U(VI) and CD/GO, and formed strong inner-sphere surface complexes with U(VI). Sorption isotherms of U(VI) or HA on CD/GO could be well fitted by the Langmuir model. This work highlights that CD/GO can be used as a promising material in the enrichment of U(VI) and HA from wastewater in U(VI) and humic substances obtained by environmental pollution cleanup.

关键词：氧化石墨腐殖酸环糊精改性除铀 Langmuir模型 X射线光电子能谱法铀(VI)

In-situ reduction synthesis of manganese dioxide@polypyrrole core/shell nanomaterial for highly efficient enrichment of U(Ⅵ) and Eu(Ⅲ)

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Science China Chemistry 2018年第7期61卷 812-823页

作者： Wen Yao Yihan Wu Hongwei Pang Xiangxue wang Shujun Yu xiangke wang College of Environmental Science and Engineering North China Electric Power University Department of Environmental Science and Engineering North China Electric Power University Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions and School for Radiological and Interdisciplinary Sciences Soochow University

Radionuclides with long half-life are toxic,and thereby result in serious threat to human beings and ecological ***,a simple two-step synthesis method was used to prepare manganese dioxide@polypyrrole(Mn O_2@PPy)core/shell structures for efficient removal of U(Ⅵ)and Eu(Ⅲ)from aqueous *** adsorption of U(Ⅵ)and Eu(Ⅲ)were investigated under different kinds of experimental *** experimental results suggested that the adsorption of U(Ⅵ)and Eu(Ⅲ)on Mn O_2@PPy were greatly affected by p H.U(Ⅵ)adsorption on Mn O_2@PPy was independent of ionic strength at p H***,Eu(Ⅲ)adsorption on Mn O_2@PPy was independent of ionic strength at the whole p H range of experimental *** maximum adsorption capacities(q_(max))of U(Ⅵ)and Eu(Ⅲ)were 63.04 and54.74 mg g^(-1)at T=298 K,*** BET,XRD,FTIR and XPS analysis evidenced that high adsorption capacities of U(Ⅵ)and Eu(Ⅲ)on Mn O_2@PPy were mainly due to high surface area and rich metal oxygen-containing group(i.e.,Mn–OH and Mn–O),and the interaction was mainly attributed to strong surface complexation and electrostatic *** study highlighted the excellent adsorption performance of U(Ⅵ)and Eu(Ⅲ)on Mn O_2@PPy and could provide the reference for the elimination of radionuclides in real wastewater management.

关键词：合成方法 Eu 锰放射性核种试验性半衰期 Mn 吸附

Event-triggered encirclement control of multi-agent systems with bearing rigidity

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Science China(Information Sciences) 2017年第11期60卷 91-108页

作者： Yangguang YU Zhiwen ZENG Zhongkui LI xiangke wang Lincheng SHEN College of Mechatronics & Automation National University of Defense Technology State Key Laboratory for Turbulence and Complex Systems Department of Mechanics and Aerospace EngineeringCollege of Engineering Peking University

In recent years, the problem of multi-agent encirclement has attained much attention and was extensively studied. However, few work consider the factor that the on-board calculation as well as the communication capacity in the multi-agent system is limited. We investigate the encirclement control by employing the newly developed bearing rigidity theory and event-triggered mechanism. Firstly, in order to reduce the onboard loads,the event-triggered mechanism is considered in the framework and further an event-triggered control law based on bearing rigidity is proposed. The input-to-state stability(ISS) of networked agents is also analyzed by using the Lyapunov method and the cyclic-small-gain theory. In addition, the lower bound for the inter-event times is provided. Finally, to verify the efficiency and feasibility of the proposed encirclement control law, numerical experiments are investigated.

关键词： encirclement control event-triggered multi-agent system bearing rigidity

联吡啶嗡盐共价有机框架材料合成与选择性捕获放射性高鍀酸根

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Science Bulletin 2022年第9期67卷 924-932,M0004页

作者： Mengjie Hao Zhongshan Chen Hui Yang Geoffrey I.N.Waterhouse Shengqian Ma xiangke wang College of Environmental Science and Engineering North China Electric Power UniversityBeijing 102206China MacDiarmid Institute for Advanced Materials and Nanotechnology School of Chemical SciencesThe University of AucklandAuckland 1142New Zealand Department of Chemistry University of North TexasDentonTX 76201USA

具有高比表面积及规则孔道结构的离子型共价有机框架(COF)材料表现出广泛的应用前景.本文设计合成了一种基于联吡啶嗡盐的阳离子型COF材料(PS-COF-1).PS-COF-1比表面积为2703 m^(2) g^(-1),高于目前报道的其他离子型COF材料.PS-COF-1具... 详细信息

具有高比表面积及规则孔道结构的离子型共价有机框架(COF)材料表现出广泛的应用前景.本文设计合成了一种基于联吡啶嗡盐的阳离子型COF材料(PS-COF-1).PS-COF-1比表面积为2703 m^(2) g^(-1),高于目前报道的其他离子型COF材料.PS-COF-1具有固定的一维通道(~4.5 nm)、良好的化学稳定性和耐辐照稳定性,表现出优异的吸附ReO_(4)^(-)(最大吸附量为1262 mg g^(-1))和^(99)TcO_(4)^(-)性能.进一步研究表明,PS-COF-1在高离子强度下表现出快速吸附动力学、高吸附容量和对^(99)TcO_(4)^(-)和ReO_(4)^(-)的高选择性,在模拟美国汉福德低活性废物流条件下成功选择性去除了^(99)TcO_(4)^(-).此外,PS-COF-1能够在10 min内将ReO_(4)^(-)和^(99)TcO_(4)^(-)污染水净化至饮用水级别.密度泛函理论计算表明,PS-COF-1对低电荷密度阴离子ReO_(4)^(-)和^(99)TcO_(4)^(-)具有强的亲和力(优于其他常见阴离子,如Cl^(-),NO_(3)^(-),SO_(4)^(2-),CO_(3)^(2-)),阐明了PS-COF-选择性吸附^(99)TcO_(4)^(-)的机理.本文展示了一种用于选择性捕获放射性核素新型阳离子COF吸附剂,为放射性污染治理提供了重要的理论依据和指导.

关键词：密度泛函理论计算电荷密度联吡啶设计合成离子强度选择性吸附辐照稳定性吸附动力学

A brief review of graphene-based material synthesis and its application in environmental pollution management

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Chinese Science Bulletin 2012年第11期57卷 1223-1234页

作者： LU Kui ZHAO GuiXia wang xiangke Key Laboratory of Audit Information Engineering Nanjing Audit UniversityNanjing 210029China Key Laboratory of Novel Thin Film Solar Cells Institute of Plasma PhysicsChinese Academy of SciencesHefei 230031China

Graphene is an interesting two-dimensional carbon allotrope that has attracted considerable research interest because of its unique structure and physicochemical properties. Studies have been conducted on graphene-based nanomaterials including modified graphene, graphene/semiconductor hybrids, graphene/metal nanoparticle composites, and graphene-complex oxide composites. These nanomaterials inherit the unique properties of graphene, and the addition of functional groups or the nanoparticle composites on their surfaces improves their performance. Applications of these materials in pollutant removal and environmental remediation have been explored. From the viewpoint of environmental chemistry and materials, this paper reviews recent important advances in synthesis of graphene-related materials and their application in treatment of environmental pollution. The roles of graphene-based materials in pollutant removal and potential research are discussed.

关键词：污染物去除改性石墨应用环境管理合成纳米复合材料纳米材料基料

Toxicity and mechanisms of action of titanium dioxide nanoparticles in living organisms

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Journal of Environmental Sciences 2019年第1期31卷 40-53页

作者： Jing Hou Luyao wang Chunjie wang Songlin Zhang Haiqiang Liu Shiguo Li xiangke wang College of Environmental Science and Engineering North China Electric Power University Research Center for Eco-Environmental Sciences Chinese Academy of Sciences

Titanium dioxide nanoparticles(TiO_2 NPs) are one of the most widely used nanomaterials in the consumer products, agriculture, and energy sectors. Their large demand and widespread applications will inevitably cause damage to organisms and ecosystems. A better understanding of TiO_2 NP toxicity in living organisms may promote risk assessment and safe use practices of these nanomaterials. This review summarizes the toxic effects of TiO_2 NPs on multiple taxa of microorganisms, algae, plants, invertebrates, and vertebrates. The mechanism of TiO_2 NP toxicity to organisms can be outlined in three aspects: The Reactive Oxygen Species(ROS)produced by TiO_2 NPs following the induction of electron–hole pairs; cell wall damage and lipid peroxidation of the cell membrane caused by NP-cell attachment by electrostatic force owing to the large surface area of TiO_2 NPs; and TiO_2 NP attachment to intracellular organelles and biological macromolecules following damage to the cell membranes.

关键词： TiO2 nanoparticles Particle size Exposure Oxidative stress Living organisms

Interaction of radionuclides with natural and manmade materials using XAFS technique

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Science China Chemistry 2017年第2期60卷 170-187页

作者： Shujun Yu Xiangxue wang Shitong Yang Guodong Sheng Ahmed Alsaedi Tasawar Hayat xiangke wang School of Environment and Chemical Engineering North China Electric Power UniversityBeijing 102206China Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions Suzhou 215123China College of Chemistry and Chemical Engineering Shaoxing UniversityShaoxing 312000China Nonlinear Analysis and Applied Mathematics(NAAM)Research Group Faculty of ScienceKing Abdulaziz UniversityJeddah 21589Saudi Arabia

The X-ray absorption fine structure(XAFS)technology has exhibited a very unique application in the study of sorption mechanism,chemical species and microstructures of radionuclides at the natural solid-water *** this review,the interaction mechanism of radionuclides with clay minerals and nanomaterials under different environmental conditions are summarized from the XAFS spectroscopy *** coordination number and the bond distances of radionuclides,the oxidation-reduction reactions,the influence of humic substances and microorganisms on the species and structures of radionuclides at molecule level are reviewed and *** review is helpful to understand the interactions of radionuclides with oxides,natural clay minerals and nanomaterials,which is also crucial to evaluate the physicochemical behaviors of radionuclides in the natural environment.

关键词：放射性核素 XAFS 纳米材料自然环境相互作用 X射线吸收精细结构技术氧化还原反应