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Transformations of particles, metal elements and natural organic matter in different water treatment processes

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Journal of Environmental Sciences 2007年第3期19卷 271-277页

作者： YAN Ming-quan WANG Dong-sheng shi Bao-you wei qun-shan QU Jiu-hui TANG Hong-xiao State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Characterizing natural organic matter （NOM）, particles and elements in different water treatment processes can give a useful information to optimize water treatment operations. In this article, transformations of particles, metal elements and NOM in a pilot-scale water treatment plant were investigated by laser light granularity system, particle counter, glass-fiber membrane filtration, inductively coupled plasma-optical emission spectroscopy, ultra filtration and resin absorbents fractionation. The results showed that particles, NOM and trihalomethane formation precursors were removed synergistically by sequential treatment of different processes. Preozonation markedly changed the polarity and molecular weight of NOM, and it could be conducive to the following coagulation process through destabilizing particles and colloids; mid-ozonation enhanced the subsequent granular activated carbon （GAC） filtration process by decreasing molecular weight of organic matters. Coagulation-flotation and GAC were more efficient in removing fixed suspended solids and larger particles; while sand-filtration was more efficient in removing volatile suspended solids and smaller particles. Flotation performed better than sedimentation in terms of particle and NOM removal. The type of coagulant could greatly affect the performance of coagulation-flotation. Pre-hydrolyzed composite coagulant （HPAC） was superior to FeCl3 concerning the removals of hydrophobic dissolved organic carbon and volatile suspended solids. The leakages of flocs from sand-filtration and microorganisms from GAC should be mitigated to ensure the reliability of the whole treatment system.

关键词： flotation fixed suspended solid trihalomethane formation potential ultra filtration resin absorbent fractionation

Quantum public-key crypto via EPR pairs

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 58-63页

作者： Xiang-qun Fu Hong-wei Li Jian-Hong shi Tan Li Wan-Su Bao Henan Key Laboratory of Quantum Information and Cryptography Information Engineering University Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China

With the development of quantum computing technology, quantum public-key cryptography is gradually becoming an alternative to the existing classical public-key cryptography. This paper designs a quantum trapdoor one-way function via EPR pairs and quantum measurements. Based on this, a new quantum public-key cryptosystem is presented, which offers forward security,and can resist the chosen-plaintext attack and chosen-ciphertext attack. Compared with the existing quantum public-key cryptos,eavesdropping can be automatically detected in this new quantum public-key cryptosystem under a necessary condition, which is also detailed in the paper.

关键词： quantum public-key crypto trapdoor one-way function EPR pairs

pH-dependent Synthesis of Octa-nuclear Uranyl-oxalate Network Mediated by U-shaped Linkers

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无机材料学报 2020年第2期35卷 243-249,I0009-I0014页

作者： WU Si MEI Lei HU Kong-Qiu CHAI Zhi-Fang NIE Chang-Ming shi wei-qun School of Chemistry and Chemical Engineering University of South ChinaHengyang 421001China Laboratory of Nuclear Energy Chemistry Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China Engineering Laboratory of Advanced Energy Materials Ningbo Institute of Industrial TechnologyChinese Academy of SciencesNingbo 315201China

In this work,we report a novel octa-nuclear uranyl(U8)motif[(UO2)8O4(μ3-OH)2(μ2-OH)2]4+embedded in a uranyl-oxalate coordination polymer(compound 1)based on a U-shaped linker with extra-long xylylene chains for stabilizing the resulting high-nuclear motif through additional cross-linking connectivity.A comparison with dimeric and monomeric uranyl compounds obtained at different pH value from the same hydrothermal system reveals that,solution pH plays a vital role in formation of this octa-nuclear uranyl motif by promoting hydrolysis of uranyl *** high similarity of eight uranium centers in this nearly planar U8 motif here,overlapping and broadening of signals in fluorescence,infra-red(IR)and Raman spectra can be found.

关键词： actinide coordination polymers octa-nuclear uranyl U-shaped Linker pH effect

Achieving Actinide and Lanthanide Group Separation with Hard-Soft Donor Combined Ligands

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Achieving Actinide and Lanthanide Group Separation with Hard...

碱化插层二维过渡金属碳化物的制备及其对铀酰离子的电化学检测

中国化学会第29届学术年会

作者： shi wei-qun Zhao Yu-liang Chai Zhi-fang Key Laboratory of Nuclear Radiation and Nuclear Energy Technology and Key Laboratory For Biomedical Effects of Nanomaterials and Nanosafety Institute of High Energy PhysicsChinese Academy of Sciences National Center for Nanoscience and Technology of China School of Radiological and Interdisciplinary Sciences Soochow University

Group separation of actinides over lanthanides is extremely challenging in spent nuclear *** extractant tributyl phosphate(TBP)used in PUREX process can efficiently extract uranium(VI)and plutonium(IV),whereas it has no extractability towards trivalent minor actinides(MA).In recent years,nitrogen atom-containing soft donors such as 2,6-bis(5,6-dialkyl-1,2,4-triazin-3-yl)pyridine(R-BTP),2,6-bis(5,6-dialkyl-1,2,4-triazin-3-yl)-2,2’-bipyridine(R-BTBP),and 2,9-bis-(5,6-dialkyl-1,2,4-triazin-3-yl)-1,10-phenanthroline(R-BTPhen)ligands have been considered as successful representatives for the separation of Ln(Ⅲ)/MA(Ⅲ).Nevertheless,these ligands are not efficient towards uranium(VI)and plutonium(IV).Hence,it is meaningful to design a versatile ligand which can extract all *** tremendous systematically theoretical works,we successfully found a phenanthrolinebased tetradentate ligand with hard-soft donors combined in the same molecule,N,N′-diethyl-N,N′-ditolyl-2,9-diamide-1,10-phenanthroline(Et-Tol-DAPhen),for the group separation of actinides over *** ligand exhibits excellent extraction ability and high selectivity toward hexavalent,tetravalent,and trivalent actinides over lanthanides in highly acidic solution.

关键词：

来源： cnki会议评论

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无机材料学报 2019年第1期34卷 85-90页

作者：樊懋王琳裴承新石伟群国民核生化灾害防护国家重点实验室北京102205 中国科学院高能物理研究所北京100049

二维过渡金属碳化物(MXenes)具有良好的电化学性能与辐照稳定性,其在放射性核素电化学检测领域有潜在应用价值。本研究通过碱活化的方式处理碳化钛型MXene(Ti_3C_2T_x),随后将钾插层的Ti_3C_2T_x(K-Ti_3C_2T_x)负载到玻碳电极(GCE)上得... 详细信息

二维过渡金属碳化物(MXenes)具有良好的电化学性能与辐照稳定性,其在放射性核素电化学检测领域有潜在应用价值。本研究通过碱活化的方式处理碳化钛型MXene(Ti_3C_2T_x),随后将钾插层的Ti_3C_2T_x(K-Ti_3C_2T_x)负载到玻碳电极(GCE)上得到K-Ti_3C_2T_x/GCE修饰电极。采用XRD、SEM、XPS等手段分别对Ti_3C_2T_x和K-Ti_3C_2T_x进行分析表征,并进一步研究了K-Ti_3C_2T_x/GCE对痕量铀酰离子(UO_2^(2+))的电化学检测性能。循环伏安(CV)实验结果表明,相比于GCE电极, K-Ti_3C_2T_x/GCE修饰电极对UO_2^(2+)的电化学响应显著增强。进一步使用差分脉冲伏安法(DPV)扫描,发现pH=4.0时, K-Ti_3C_2T_x/GCE修饰电极对UO_2^(2+)在铀浓度0.5～10 mg/L范围内呈现良好的线性检测关系,本方法的检测限为0.083 mg/L(S/N=3),稳定性和重复性好。

关键词：铀酰离子碱化Ti3C2Tx 电化学检测

Identifying the dynamic behaviors in complete reconstruction of Co-based complex precatalysts during electrocatalytic oxygen evolution

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Journal of Energy Chemistry 2025年第1期100卷 226-233页

作者： Jingfang Zhang Danyang Wu Linke Cai Youluan Lu Fanpeng Cheng Lijuan shi qun Yi Yao Liu Yi Huang Key Laboratory of Green Chemical Engineering Process of Ministry of Education Engineering Research Center of Phosphorus Resources Development and Utilization of Ministry of Education Hubei Key Laboratory of Novel Reactor and Green Chemical Technology School of Chemical Engineering & Pharmacy Wuhan Institute of Technology Key Laboratory of Pesticide & Chemical Biology of Ministry of Education Engineering Research Center of Photoenergy Utilization for Pollution Control and Carbon Reduction of Ministry of Education College of Chemistry Central China Normal University College of Materials Science and Engineering Fuzhou University

Transition metal-based nanomaterials have emerged as promising electrocatalysts for oxygen evolution reaction（OER）. Considerable research efforts have shown that self-reconstruction occurs on these nanomaterials under operating conditions of OER process. However, most of them undergo incomplete reconstruction with limited thickness of reconstruction layer, leading to low component utilization and arduous exploration of real catalytic mechanism. Herein, we identify the dynamic behaviors in complete reconstruction of Co-based complexes during OER. The hollow phytic acid（PA） cross-linked CoFe-based complex nanoboxes with porous nanowalls are designed because of their good electrolyte penetration and mass transport ability, in favor of the fast and complete reconstruction. A series of experiment characterizations demonstrate that the reconstruction process includes the fast substitution of PA by OH-to form Co（Fe）(OH)xand subsequent potential-driven oxidation to Co（Fe）OOH. The obtained CoFeOOH delivers a low overpotential of 290 mV at a current density of 10 mA cm-2and a long-term *** experiment results together with theory calculations reveal that the Fe incorporation can result in the electron rearrangement of reconstructed CoFeOOH and optimization of their electronic structure,accounting for the enhanced OER activity. The work provides new insights into complete reconstruction of metal-based complexes during OER and offers guidelines for rational design of high-performance electrocatalysts.

关键词： Oxygen evolution reaction

碱化Ti3C2Tx MXene对Eu（Ⅲ）高效去除与机理研究

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无机材料学报 2020年第1期35卷 65-72页

作者：宋环王琳王宏青石伟群南华大学化学化工学院衡阳421001 中国科学院高能物理研究所北京100049

对无机二维过渡金属碳化物(MXene)进行碱化处理,成功制备了碱化碳化钛(Na-Ti3C2Tx),用于对Eu(Ⅲ)的快速去除。采用固液比、溶液pH和离子强度、动力学、等温线、热力学等批次实验方法对Na-Ti3C2Tx去除Eu(Ⅲ)的行为进行了系统研究。实验... 详细信息

对无机二维过渡金属碳化物(MXene)进行碱化处理,成功制备了碱化碳化钛(Na-Ti3C2Tx),用于对Eu(Ⅲ)的快速去除。采用固液比、溶液pH和离子强度、动力学、等温线、热力学等批次实验方法对Na-Ti3C2Tx去除Eu(Ⅲ)的行为进行了系统研究。实验结果表明:整个吸附过程受溶液pH和离子强度影响较大,吸附过程在很短的时间(5 min)就达到了吸附平衡,该过程更符合Langmuir吸附模型,在298 K时最大吸附容量可达54.05 mg/g。热力学结果表明Na-Ti3C2Tx对Eu(Ⅲ)的吸附为自发吸热反应过程。使用能量色散X射线光谱(EDS)、粉末XRD和扩展X射线吸收精细结构光谱学(EXAFS)对其吸附机理进行了分析,结果表明酸性条件下主要的吸附机理是Eu^3+离子与MXene层间的Na^+离子发生了离子交换,吸附后的Eu(Ⅲ)主要以外层配位络合物的形式存在,而近中性条件下则出现了内配位络合作用。鉴于Na-Ti3C2Tx具有较低的合成成本与优异的吸附性能,该材料有望应用于放射性废水中三价次锕系核素与镧系核素的快速高效清除。

关键词： Na-Ti3C2Tx Eu(Ⅲ) 去除作用机制

施维群教授诊治慢性乙型肝炎肝硬化用药经验的数据挖掘研究

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中西医结合肝病杂志 2022年第10期32卷 912-915页

作者：来杰锋傅克模施维群杭州市余杭区中医院浙江杭州311106 浙江中医药大学附属第二医院

目的:基于数据挖掘技术分析施维群教授治疗慢性乙型肝炎肝硬化患者的临床用药规律进行深入全面的分析,归纳总结其用药规律及组方特点,促进名老中医经验的传承与创新。方法:收集整理2016年1月至2017年12月杭州市余杭区中医院和浙江中医... 详细信息

目的:基于数据挖掘技术分析施维群教授治疗慢性乙型肝炎肝硬化患者的临床用药规律进行深入全面的分析,归纳总结其用药规律及组方特点,促进名老中医经验的传承与创新。方法:收集整理2016年1月至2017年12月杭州市余杭区中医院和浙江中医药大学附属第二医院施维群教授门诊就诊的88例慢性乙型肝炎肝硬化患者的264张中药处方,并将处方信息进行标准化预处理,录入中医传承辅助系统(V2.5),运用TCMISS中“统计报表”和“数据分析”模块,通过频次统计方法、关联规则挖掘方法,将所选病案数据客观化表现出来,并结合施教授相关学术思想及理论,总结其用药特点及规律。结果:对筛选出的264张处方进行分析,使用频次≥100次属于高频次药物,共有12味药,分别是白术、茯苓、甘草、白芍、枳壳、薏苡仁、黄芪、当归、白花蛇舌草、砂仁、牡丹皮、大腹皮等。运用关联规则挖掘方法,分别设置支持度为40%,置信度为0.8,得到常用药物组合共18条。结论:施维群教授对慢性乙型肝炎肝硬化的治疗独具特色,其“顾护脾胃”的思想贯穿于疾病治疗的始终,临床上多用益气健脾、行气利水、活血化瘀之品,其组方的核心药物为:白术、茯苓、甘草、白芍、枳壳、薏苡仁、黄芪、当归、白花蛇舌草。中医传承辅助系统用于名老中医经验的传承推广、临床医师经验的总结有非常重要的辅助作用,具有一定的科学价值和社会意义。

关键词：数据挖掘中医传承辅助系统慢性乙型肝炎肝硬化用药规律名医经验

锕系金属掺杂硼团簇AnB_(7)(An=Ac、Th、Am、Cm)的理论研究

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核化学与放射化学 2023年第2期45卷 160-169,I0005页

作者：张乃心王聪芝石伟群中国科学院高能物理研究所核能放射化学实验室北京100049

通过金属掺杂,硼团簇可以表现出特殊的结构特征和化学性质。尽管主族金属、过渡金属和镧系金属掺杂的硼团簇已被相继报道,但目前锕系金属掺杂的硼团簇研究相对较少。本工作使用密度泛函理论(DFT)预测了一系列锕系金属掺杂硼团簇AnB_(7)(... 详细信息

通过金属掺杂,硼团簇可以表现出特殊的结构特征和化学性质。尽管主族金属、过渡金属和镧系金属掺杂的硼团簇已被相继报道,但目前锕系金属掺杂的硼团簇研究相对较少。本工作使用密度泛函理论(DFT)预测了一系列锕系金属掺杂硼团簇AnB_(7)(An=Ac、Th、Am、Cm)。理论计算表明,其能量最低的结构分别为C_(6)v AcB_(7)、C_(2)v ThB_(7)、C_(2)v AmB_(7)和C_(6)v CmB_(7),且均为半夹心构型。在每个AnB_(7)体系中,B_(3)-7具有六个离域的π电子和六个离域的σ电子,均为双重芳香性团簇。成键性质分析表明Am-B和Cm-B键的共价相互作用强于Ac-B和Th-B键。此外,这些硼团簇均非常稳定,且AmB_(7)和CmB_(7)稳定性更高,而共价相互作用是影响AnB_(7)稳定性的重要因素。本工作丰富了锕系金属掺杂的硼团簇的种类,并为设计锕系金属掺杂硼团簇材料提供了理论基础。

关键词：锕系金属硼团簇密度泛函理论共价性