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Hydroxylation of 3-nitrotyrosine by hydroxyl radical

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Chinese Chemical Letters 2007年第5期18卷 542-544页

作者： Jun Chen Dong wei qun shi Yu Fen Zhao Yan Mei Li Key Laboratory of Bioorganic Phosphorous Chemistry ＆ Chemical Biology （Ministry of Education） Department of Chemistry Tsinghua University Beijing 100084 China

Hydroxylation of 3-nitrotyrosine （3-NT） and 3-NT containing peptide Gly-nitroTyr-Gly in aqueous solution by hydroxyl radical were investigated with gamma irradiation. The structures of the hydroxylated products were confirmed by electrospray ionization mass spectrometry and ^1H NMR spectrometry. The reactivity of 3-nitrotyrosine has been investigated using density functional theory （DFT） calculation.

关键词： 3-Nitrotyrosine Hydroxyl radical DFT Selective hydroxylation

Condition dependence of Zr electrochemical reactions and morphological evolution of Zr deposits in molten salt

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Science China Chemistry 2017年第2期60卷 264-274页

作者： Kui Liu Ya-Lan Liu Jing-Wen Pang Li-Yong Yuan Lin Wang Zhi-Fang Chai wei-qun shi Laboratory of Nuclear Energy Chemistry Institute of High Energy PhysicsChinese Academy of Sciences School of Radiological & Interdisciplinary Sciences Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education InstitutionsSoochow University

This work presents a comprehensive study for the electrochemical behaviors of zirconium in LiCl-KCl *** effects of stirring,temperature and Zr concentration on the electrode reactions,the ZrCl_4 sublimation from the melt,microcosmic morphologies of Zr deposits(ZrCl and Zr)obtained at different potential and temperature have been *** behaviors of Zr(Ⅳ),on a large concentration range from 0.13%to 2.28%in melt,show a multiple-step reaction involving Zr(Ⅳ),Zr(Ⅱ),ZrCl and Zr *** plays a crucial role on the changes of Zr(IV)reduction behavior on the solid *** Zr(Ⅳ)/ZrCl couple is more easily observed at lower temperature and gradually diminishes with the increase of *** Zr(Ⅳ)/Zr(Ⅱ)and Zr(Ⅱ)/Zr reactions are predominant on the W electrode at higher *** 673 K,a layered structure of insoluble ZrCl formed by potentiostatic electrolyses at 1.1 V was visualized by scanning electron microscopy-energy dispersive X-ray(SEM-EDS),while only Zr metal particles was observed at higher temperature than 773 *** evolution of the Zr-based structure and size corresponding to the ZrCl and Zr metal based on different potentiostatic electrolysis was *** average particle size of the Zr metalparticles increases with the increase of temperature.

关键词： zirconium electrochemistry influence factor LiCl-KCl pyroprocessing

A large-scale screening of metal-organic frameworks for iodine capture combining molecular simulation and machine learning

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Frontiers of Environmental Science & Engineering 2023年第12期17卷 71-84页

作者： Min Cheng Zhiyuan Zhang shihui Wang Kexin Bi Kong-qiu Hu Zhongde Dai Yiyang Dai Chong Liu Li Zhou Xu Ji wei-qun shi School of Chemical Engineering Sichuan UniversityChengdu 610065China Laboratory of Nuclear Energy Chemistry Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China College of Architecture and Environment Sichuan UniversityChengdu 610065China School of Carbon Neutrality Future Technology Sichuan UniversityChengdu 610065China Department of Bioprocess Engineering Institute of BiotechnologyTechnische Universität BerlinBerlin 10623Germany

We performed large-scale molecular simulation to screen and identify metal-organic framework materials for gaseous iodine capture,as part of our ongoing effort in addressing management and handling issues of various radionuclides in the grand scheme of spent nuclear fuel *** from the computation-ready experimental(CoRE)metal-organic frameworks(MOFs)database,grand canonical Monte Carlo simulation was employed to predict the iodine uptake values of the MOFs.A ranking list of MOFs based on their iodine uptake capabilities was generated,with the Top 10 candidates identified and their respective adsorption sites ***,machine learning was used to establish structure-property relationships to correlate MOFs’various structural and chemical features with their corresponding performances in iodine capture,yielding interpretable common features and design rules for viable MOF *** research strategy and framework of the present study could aid the development of high-performing MOF adsorbents for capture and recovery of radioactive iodine,and moreover,other volatile environmentally hazardous species.

关键词： Iodine capture Metal-organic framework Large-scale screening Molecular simulation Machine learning

Silver Ion-Induced Formation of Unprecedented Thorium Nonamer Clusters via Lacuna-Construction Strategy

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CCS Chemistry 2023年第5期5卷 1144-1153页

作者： Xiang-He Kong qun-Yan Wu Lei Mei Li-Wen Zeng Zhi-wei Huang Ji-Pan Yu Chang-Ming Nie John KGibson Zhi-Fang Chai Kong-Qiu Hu wei-qun shi Laboratory of Nuclear Energy Chemistry Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049 School of Chemistry and Chemical Engineering University of South ChinaHengyang 421001 Chemical Sciences Division Lawrence Berkeley National Laboratory(LBNL)BerkeleyCalifornia 94720

Herein,we report the synthesis and structures of two novel mixed-metal clusters denoted as Th_(9)Ag_(6)and Th_(9)Ag_(12).Both clusters feature unprecedented Th_(9)*** cores are tricapped trigonal prism moieties that are novel among *** alternative synthesis routes indicate that the Th_(9)clusters are accessible only through slow introduction of Ag_(+)into a solution containing a Th6 cluster modified with 2-picolinic *** rapid addition of Ag_(+)leads to dissociation of the Th6 cluster with formation of a high-purity(ThAg)_(∞)two-dimensional layered structure material.A mechanism for cluster dissociation and reassembly to yield Th_(9)from Th6 is proposed that is consistent with spectroscopic observations and computational *** of Ag⋯Ag andπ–πinteractions,the Th_(9)Ag_(12)cluster exhibits high stability in air,at elevated temperature,underγ-irradiation,and in common solvents.

关键词： thorium nonamer clusters silver ion lacuna-construction strategy dissociation and reassembly high stability

Actinide-Organic Rotaxane Compounds

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Actinide-Organic Rotaxane Compounds

全国第十九届大环化学暨第十一届超分子化学学术讨论会

作者： wei-qun shi Lei Mei Zhi-fang Chai Laboratory of Nuclear Energy Chemistry Institute of High Energy Physics Chinese Academy of Sciences

Metal-organic materials with dynamic components, such as mechanically-interlocked rotaxane molecules(MIMs), integrate the attractive feature of flexibility into rigid frameworks as well as broad *** plenty of rotaxane-based coordination polymers, transition metal ions and lanthanide ions have been intensively studied due to their rich coordination patterns and ***, metal-organic polyrotaxanes containing actinide cations have been rarely reported. Hence, we are currently pursuing the preparation of actinide polyrotaxanes from actinide cation and pseudorotaxane ligands containing cucurbituril *** effort has finally succeeded to produce a series of actinide polyrotaxanes with a rich library of structures.

关键词： Metal-Rotaxane Coordination Polymer Supramolecular Pseudorotaxane Actinides Cucurbituril Structural Regulation

Influence of Solvation Effect on Aqueous U(Ⅵ) Species Interaction with the Calcite(104) Surface: A Combined DFT and Molecular Dynamics Study

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Influence of Solvation Effect on Aqueous U(Ⅵ) Species Inter...

第十三届全国量子化学会议

作者： Jian-Hui Lan Zhi-Fang Chai wei-qun shi Laboratory of Nuclear Energy Chemistry and Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety Institute of High Energy Physics Chinese Academy of Sciences School of Radiological & Interdisciplinary Sciences and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Soochow University

In environment, adsorption and precipitation of radionuclides onto minerals can be deemed as the second barrier and a crucial factor that affect their migration behavior. Therefore, interaction of aqueous actinide species with minerals has been extensively studied, yet issues such as interaction mechanism, speciation, and stability remain debated topics. Here we present a combined DFT and molecular dynamics study of uranyl interaction with the calcite（104） surface. On one hand, the formation stability of a series of inner-sphere surface complexes was compared based on a fully hydrated surface. Our results show that, besides the direct U-Osurf bonding with a neighboring O（u） atom, the uranyl multicarbonates prefer to occupy two diagonal Ca（o） sites while the other uranyl species tend to occupy a single Ca（o） site. Energy analysis shows that adsorption of positively charged uranyl species is most favorable with negative formation energies. The formation energies within the range of 20.7-43.0 kcal/mol indicate that adsorption of neutral uranyl species is an endothermic process. However, the formation of negatively charged uranyl complexes is highly endothermic owing to the electrostatic repulsion between the surface and the adsorbate. The solvation energy of the surface becomes more negative to different extent after complexing with the uranyl species, among which the UO（CO）Ca species contributes to the largest degree of energy changes（-53 kcal/mol）. This makes full solvation correction crucial for reliably predicting the corresponding formation energy. On the other hand, the incorporation mechanisms were studied by analyzing various ion exchange reactions between the uranyl species and the surface Ca atoms, and we found that the reaction with UO（CO）（HO）-as the reactant becomes the most favorable one.

关键词： actinide adsorption calcite density functional theory

Adsorption of U(Ⅵ) by amino-functionalized magnetic ordered mesoporous silica

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Adsorption of U(Ⅵ) by amino-functionalized magnetic ordered...

中国化学会第九届全国无机化学学术会议

作者： Guo Wenlu Yuan Liyong Nie Changming wei-qun shi Institute of High Energy Physics Chinese Academy of Sciences School of Chemistry and Chemical Engineering University of South China

Uranium, as a predominant fuel ingredient for most nuclear reactors, is the key element in nuclear fuel cycle. Moreover, its chemical and physiological toxicity can be never negligible when it is open for human exposure. In this regard, efficient removal or recovery of mobile hexavalent uranium(U(VI)) from radioactive waste water and nuclear industry involved environment is of pivotal importance for human health and environmental safety. In this study, an amino functionalized magnetic mesoporous silica with pisiform structure was fabricated, aiming at convenient removal of U(VI) from aqueous solution. The synthesized material possesses highly ordered mesoporous structure with large surface area, uniform pore size, excellent thermal stability, and quick magnetic response. The batch sorption tests revealed that this material is indeed an effective U(VI) sorbent with fast sorption kinetics, large sorption capacity of more than 160 mg/g at p H=5.0, and desirable selectivity towards U(VI) ions over a range of competing metal ions. The sorbent can be readily separated from solution by simply adding an external magnetic field. FTIR analysis were employed for an in-depth probe into the sorption mode of U(VI) onto the sorbent.

关键词： Amino Magnetic Ordered mesoporous silica Uranium Adsorption

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

Size- and Shape-Controlled Synthesis of Actinide Oxide Nanostructures

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Size- and Shape-Controlled Synthesis of Actinide Oxide Nanos...

中国化学会第九届全国无机化学学术会议

作者： Lin Wang Ran Zhao Zhi-Fang Chai wei-qun shi Institute of High Energy Physics Chinese Academy of Sciences School of Radiological & Interdisciplinary Sciences and Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Soochow University

Actinide oxide nanomaterials have drawn much attention recently, as they display many attractive properties that are very promising for applications as new types of nuclear fuels and highly efficient catalysts. We report here the fabrication of a series of actinide oxide nanomaterials with different morphologies（e.g. nanoparticles, one-dimensional nanostructures and hierarchical nano-/microstructures） by using various synthesis approaches including hydrothermal reaction, hard template nanocasting and electrodeposition technique. The size and shape of these novel nanostructures can be well controlled through manipulating the related experimental parameters. We have also studied the corresponding growth mechanism of these actinide oxide nanostructures. The findings in these works will greatly enrich our fundamental understanding of the growth process and the size- and shape-control of actinide oxide nanostructures, and also promote their applications in catalysis, nuclear fuels, and other fields.

关键词： actinide oxide nanostructures hydrothermal method hard template method