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Americium/lanthanide separation enabled by a distinct polyoxometalate cluster

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Science China Chemistry 2024年第1期67卷 312-313页

作者： Hui Yang xiangke wang Shengqian Ma College of Environmental Science and Engineering North China Electric Power UniversityBeijing 102206P.R.China Department of Chemistry University of North TexasDentonTexas 76201United States

Nuclear energy is viewed as a low carbon-emission electricity-generating technology with high-energy density,which has attracted extensive attention and shown broad development prospects[1].However,to ensure sustainability and cleanability in the development of nuclear energy,one crucial challenge is to exploit efficient and economical technologies to simultaneously recover fissionable nuclides from nuclear waste and separate long-lived toxic fission products[2].

关键词： lanthanide separation cluster

COF-based membranes for liquid phase separation:Preparation,mechanism and perspective

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Journal of Environmental Sciences 2024年第7期141卷 63-89页

作者： Yujie Zhao He Gu Yilun Zhou CaimeiWen Xiaolu Liu Suhua wang Zhongshan Chen Hui Yang xiangke wang College of Environmental Science and Engineering North China Electric Power UniversityBeijing 102206China School of Environmental Science and Engineering Guangdong University of Petrochemical TechnologyMaoming 525000China

Covalent organic frameworks(COFs)are a new kind of crystalline porous materials composed of organic molecules connected by covalent bonds,processes the characteristics of low density,large specific surface area,adjustable pore size and structure,and easy to functionalize,which have been widely used in the field of membrane separation ***,there are more and more researches focusing on the preparation methods,separation application,and mechanism of COF membranes,which need to be further summarized and *** this review,we primarily summarized several conventional preparation methods,such as two-phase interfacial polymerization,in-situ growth on substrate,unidirectional diffusion method,layer-by-layer assembly method,mixed matrix membranes,and so *** advantages and disadvantages of each method are briefly *** application potential of COF membrane in liquid separation are introduced from four aspects:dyeing wastewater treatment,heavy metal removal,seawater desalination and oil-water ***,the mechanisms including pore structure,hydrophilic/hydrophobic,electrostatic repulsion/attraction and Donnan effect are *** the efficient removal of different kind of pollutions,researchers can select different ligands to construct membranes with specific pore size,hydrophily,salt or organic rejection ability and functional *** ideas for the design and preparation of COF membranes are ***,the future direction and challenges of the next generation of COF membranes in the field of separation are prospected.

关键词： Covalent organic frameworks Membrane materials Liquid phase separation Separation mechanism

Affine formation tracking control of unmanned aerial vehicles

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Frontiers of Information Technology & Electronic Engineering 2022年第6期23卷 909-919页

作者： Huiming LI Hao CHEN xiangke wang College of Intelligence Science and Technology National Uniuersity of Defense TechnologyChangsha 410073China

The affine formation tracking problem for fixed-wing unmanned aerial vehicles(UAVs)is considered in this paper,where fixed-wing UAVs are modeled as unicycle-type agents with asymmetrical speed constraints.A group of UAVs are required to generate and track a time-varying target formation obtained by affinely transforming a nominal *** handle this problem,a distributed control law based on stress matrix is proposed under the leader-follower control *** is proved,theoretically,that followers can converge to the desired positions and achieve affine transformations while tracking diverse ***,a saturated control strategy is proposed to meet the speed constraints of fixed-wing UAVs,and numerical simulations are executed to verify the effectiveness of our proposed affine formation tracking control strategy in improving maneuverability.

关键词： Affine formation Fixed-wing unmanned aerial vehicles Multi-agent system

基于酚醚结构的偕胺肟基聚合物的制备及U(Ⅵ)吸附行为研究

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中国科学：化学 2024年第7期54卷 1117-1126页

作者：唐震巽吴一超王子龙郝梓淇曲钊姬濯宇王祥科资源环境系统优化教育部重点实验室华北电力大学环境科学与工程学院北京102206

核能作为一种低碳清洁的能源,是国家重点发展对象之一.铀元素是核能的重要组成部分,但我国陆地铀矿储量有限,限制了核能的发展.海洋中共有约45亿吨铀,可满足核能的长期发展需要.本文从材料结构设计出发,利用廉价的工业化原料四氟对苯二... 详细信息

核能作为一种低碳清洁的能源,是国家重点发展对象之一.铀元素是核能的重要组成部分,但我国陆地铀矿储量有限,限制了核能的发展.海洋中共有约45亿吨铀,可满足核能的长期发展需要.本文从材料结构设计出发,利用廉价的工业化原料四氟对苯二腈(TFTPN)与依昔苯酮(Exi)/4,4′-二羟基苯偶酰(DDB)进行交联及偕胺肟功能化,制备出三种酚醚结构的U(Ⅵ)吸附材料:ExiF-AO、ExiF-2-AO和DDBF-AO,并对材料结构/配体与吸附性能间的关系进行探究.结果表明,相比结构相似的线性聚合物ExiF-AO和DDBF-AO,网状交联结构的ExiF-2-AO具有更强的吸附能力,吸附量达347.5 mg/g,同时具备较好的可回收性与理化稳定性.本文从分子结构层面探讨了材料结构对U(Ⅵ)吸附的影响,为用于大规模海水提铀的功能材料的设计、制备提供了借鉴.

关键词：共价有机聚合物偕胺肟铀吸附

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氦离子化色谱仪分析高纯氘气方法的开发

低温与特气 2024年第2期42卷 37-40,50页

作者：王祥科钱阿慧朗析仪器(上海)有限公司上海201702

氘气被广泛应用于各种领域,并且是核聚变最有前景的材料之一。针对目前分析检出限低、载气较贵的问题(氖做载气),首次提出使用氦离子化检测器分析高纯氘气。其中高纯氘气中无机杂质气体氩气、氧气、氮气、甲烷、一氧化碳、二氧化碳的检... 详细信息

氘气被广泛应用于各种领域,并且是核聚变最有前景的材料之一。针对目前分析检出限低、载气较贵的问题(氖做载气),首次提出使用氦离子化检测器分析高纯氘气。其中高纯氘气中无机杂质气体氩气、氧气、氮气、甲烷、一氧化碳、二氧化碳的检出限可达0.01×10^(-6)(体积分数);使用改性氧化铝色谱柱,在77 K低温下分离;H_(2)和HD检出限可达1×10^(-6)(体积分数)。对氘气样品进行分析,达到预期分析效果。实验采用脉冲氦离子化检测器为检测手段,对高纯氘气中的杂质进行分析,提高了检出限,并且采用氦气为载气比氖气作为载气更具分析成本优势。

关键词：高纯氘气色谱分析氢-氘气体

Gaussian Process Based Modeling and Control of Affine Systems with Control Saturation Constraints

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Complex System Modeling and Simulation 2023年第3期3卷 252-260页

作者： Shulong Zhao Qipeng wang Jiayi Zheng xiangke wang College of Intelligence Science and Technology National University of Defense TechnologyChangsha 410073China

Model-based methods require an accurate dynamic model to design the ***,the hydraulic parameters of nonlinear systems,complex friction,or actuator dynamics make it challenging to obtain accurate *** this case,using the input-output data of the system to learn a dynamic model is an alternative ***,we propose a dynamic model based on the Gaussian process(GP)to construct systems with control *** GP provides a measure of model confidence,it can deal with ***,most GP-based literature considers model uncertainty but does not consider the effect of constraints on inputs in closed-loop *** auxiliary system is developed to deal with the influence of the saturation constraints of ***,we relax the nonsingular assumption of the control coefficients to construct the *** numerical results verify the rationality of the proposed approach and compare it with similar methods.

关键词： Gaussian process(GP) auxiliary system credibility constraints input

MXene/MnO_(2)对有机微污染物的类芬顿氧化降解效能与机理

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Chinese Journal of Catalysis 2024年第6期61卷 215-225页

作者：文涛郭思胜赵恒新郑宇琦张馨月顾鹏程张塞艾玥洁王祥科华北电力大学环境科学与工程学院资源与环境系统优化教育部重点实验室北京102206 安徽农业大学资源与环境学院安徽合肥230036 北京工业大学环境与生命学院北京100124

芬顿高级氧化技术是降解有机微污染物的有效手段.过一硫酸盐(PMS)类芬顿技术因具有高效的氧化剂利用率和较宽的pH操作范围,已成为目前工业中过氧化氢芬顿技术的一种有前途的替代品.非均相催化剂能够有效活化PMS,产生多种活性自由基,从... 详细信息

芬顿高级氧化技术是降解有机微污染物的有效手段.过一硫酸盐(PMS)类芬顿技术因具有高效的氧化剂利用率和较宽的pH操作范围,已成为目前工业中过氧化氢芬顿技术的一种有前途的替代品.非均相催化剂能够有效活化PMS,产生多种活性自由基,从而氧化降解有机微污染物.二维过渡金属碳化物/氮化物(MXene)具有较好的电子传输效率和可调的表面官能团,是一种良好的非均相催化材料.然而,MXene的不稳定性、反应体系的自聚集作用和不明确的活性氧(ROS)生成机制极大地限制了它们在实际环境中的广泛应用.鉴于剥离的MXene中钛的高反应活性缺陷可以原位锚定过渡金属材料,本文通过氧化还原策略,将MnO_(2)纳米颗粒原位沉积在MXene纳米片上制备了MXene/MnO_(2)复合材料.X射线衍射图中(002)峰的偏移、透射电镜和电子衍射环图中交错的晶格条纹等表征结果表明,MnO_(2)纳米颗粒均匀地负载在剥离的MXene纳米片上.X射线光电子能谱证实了MXene表面钛缺陷与MnO_(2)纳米颗粒通过氧化还原作用相连接.同时,通过调整反应时间确定了18 h原位沉积制备的MXene/MnO_(2)具有最佳的产率和双酚A降解速率.此时的复合材料能够在4 min内活化PMS去除95.9%的BPA(50 mg/L),矿化效率达到了51.2%,表现出较好的催化性能.电子顺磁共振和淬灭实验结果表明,MXene/MnO_(2)活化PMS降解BPA为非自由基途径.实验观察结合密度泛函理论计算表明,大量暴露的锰位点有效吸附并活化PMS,从而促进了单线态氧的产生.通过高价Mn-oxo相直接生成1O_(2)的普遍途径具有较高的能垒(3.34 eV).相比之下,•OOH作为中间体产生1O_(2)的途径(1.84 eV)在能量上更可行.得益于MXene的快速电荷转移能力和MnO_(2)强PMS活化能力的双重优势,工程化的MXene/MnO_(2)/PVDF催化膜对京密引水渠河水中的有机微污染物表现出高效的活性和出色的长期稳定性.综上,本文通过氧化还原原位生长策略制得了MXene/MnO_(2)催化剂,并深入研究了其在类芬顿反应中催化降解有机微污染物的性能.通过实验表征和理论计算相结合的方法,揭示了该催化剂对有机微污染物的降解机理.本研究不仅为MXene基催化剂的设计和合成提供了新的思路,也为开发可广泛应用于实际水体中处理有机微污染物的催化剂提供了参考.

关键词： MXene 二氧化锰过一硫酸盐单线态氧类芬顿反应

Optimizing iodine capture performance by metal-organic framework containing with bipyridine units

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Frontiers of Chemical Science and Engineering 2023年第4期17卷 395-403页

作者： Xinyi Yang Xiaolu Liu Yanfang Liu Xiao-Feng wang Zhongshan Chen xiangke wang School of Chemistry and Chemical Engineering University of South ChinaHengyang 421001China College of Environmental Science and Engineering North China Electric Power UniversityBeijing 102206China

Radioactive iodine exhibits medical values in radiology,but its excessive emissions can cause environmental ***,the capture of radioiodine poses significant engineering for the environment and medical *** adsorptive capture of radioactive iodine by metal-organic frameworks(MOFs)has risen to *** this work,a Th-based MOF(denoted as Th-BPYDC)was structurally designed and synthesized,consisting of[Th_(6)(μ_(3)-O)_(4)(μ_(3)-OH)_(4)(H_(2)O)6]^(12+)clusters,abundant bipyridine units,and large cavities that allowed guest molecules diffusion and ***-BPYDC exhibited the uptake capacities of 2.23 g·g^(-1) and 312.18 mg·g^(-1) towards I_(2) vapor and I_(2) dissolved in cyclohexane,respectively,surpassing its corresponding analogue *** bipyridine units boosted the adsorption performance,and Th-BPYDC showed good reusability with high *** work thus opened a new way for the synthesis of MOFs to capture radioactive iodine.

关键词： metal-organic framework iodine adsorption nuclear waste environmental remediation

Selective capture and separation of xenon and krypton using metal organic frameworks: a review

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Frontiers of Chemical Science and Engineering 2023年第12期17卷 1895-1912页

作者： Yilun Zhou Jingyi wang Yujie Zhao He Gu Zhongshan Chen Hui Yang xiangke wang College of Environmental Science and Engineering North China Electric Power UniversityBeijing 102206China

Xenon and krypton are widespread useful noble gases in commercial lighting, lasers, electronics, and medical industry. At the same time, radioactive noble gases may proliferate from used nuclear fuel and diffuse in open atmospheres. Metal organic frameworks as hotspot porous materials for gases uptake and separation are considered to be potential solutions. In this review, we comprehensively summarized recent researches on metal organic frameworks for selective capture and separation of xenon and krypton. Particularly, we followed the aspects of different optimal design strategies, including optimal pore/cage size and geometry, open metal sites, ions (anions and cations), and polar functional groups for enhancing the xenon adsorption and separation performances. Meanwhile, a comparison of each strategy and the mechanisms of xenon/krypton separation were pointed out. The separation of krypton from gases mixtures by dual-bed systems was further discussed. Finally, some existing challenges and opportunities for possible real applications were proclaimed.

关键词： metal organic frameworks xenon krypton selective separation used nuclear fuel