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Chinese Journal of Chemistry 2019年第2期37卷 155-160页

作者： Jing Gu ben-xian xiao Qin Ouyang Wei Du Ying-Chun Chen Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology West China School of PharmacySichuan UniversityChengdu 610041China College of Pharmacy Third Military Medical UniversityShapingbaChongqing 400038China

Summary of main observation and conclusion 3-Olefinic oxindoles can undergo interrupted Morita-Baylis-Hillman reaction with formaldehyde. Apart from the previous reported dephosphoration to access reductive aldol-type products, here we uncovered that completely different pathways were followed by tuning the substitutions of 3-olefinic oxin doles. In com bin ation with formalin, an unexpected domino phosphorus-ylide formation, aldol-type addition, hemeacetal formation and O-substitution process was observed to produce 1,3-dioxolane derivatives. Moreover, a switchable sequence to produce formate derivatives via a key hydride transfer process was furnished by simply replacing formalin with paraformaldehyde. Density functional theory calculations were conducted to well elucidate the catalytic reaction mechanism.

关键词： Phosphine-Catalyzed Interrupted Morita-Baylis-Hillman Reaction Switchable Domino Reactions of a-Substituted Activated Olefins Formaldehyde Mechanism Elucidation

Full-domain collaborative deployment method of multiple interference sources and evaluation of its deployment effect

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Defence Technology（防务技术） 2024年第2期32卷 572-595页

作者： Yue Wang Fuping Sun xian Wang Jinming Hao Kai xiao School of Geospatial Information The PLA Information Engineering UniversityZhengzhou 450001HenanChina

This paper realizes the full-domain collaborative deployment of multiple interference sources of the global satellite navigation system(GNSS)and evaluates the deployment effect to enhance the ability to disturb the attacker and the capability to defend the GNSS during navigation countermeasures.Key evaluation indicators for the jamming effect of GNSS suppressive and deceptive jamming sources are first created,their evaluation models are built,and their detection procedures are sorted out,as the basis for determining the deployment principles.The principles for collaboratively deploying multi-jamming sources are developed to obtain the deployment structures(including the required number,structures in demand,and corresponding positions)of three single interference sources required by collaboratively deploying.Accordingly,simulation and hardware-in-loop testing results are presented to determine a rational configuration of the collaborative deployment of multi-jamming sources in the set situation and further realize the full-domain deployment of an interference network from ground,air to space.Varied evaluation indices for the deployment effect are finally developed to evaluate the deployment effect of the proposed configuration and further verify its reliability and rationality.

关键词： Jamming effect Multiple interference sources Collaborative deployment Effect evaluation Defense capability

Crystalline-amorphous M@MNx（M=Co,Fe,Ni）encapsulated in nitrogen-doped carbon for enhanced efficient and durable hydrogen evolution reaction

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Rare Metals 2024年第4期43卷 1547-1556页

作者： Yang Yang xiao-Chuan Duan Shao-Hui Guo xian-Ming Zhang College of Materials Science and Engineering College of ChemistryKey Laboratory of Interface Science and Engineering in Advanced MaterialsTaiyuan University of Technology

Developing earth-abundant electrocatalysts for hydrogen evolution reaction（HER） is important for the sustainable energy economy.Herein,efficient and stable heterocatalysts consisting of crystalline-amorphous M@MNx（M=Co,Fe,Ni） encapsulated in N-doped carbon layers supported with N-doped graphene sheets（denoted as M@MNx@NC-NG） are synthesized by facile hydrothermal reaction and nitridation process.During the nitriding process,metal ions in M（tzbc）2（H2O）4(tzbc=4-（1H-1,2,4-triazol-1-yl） benzoic acid) complexes are reduced to crystalline M cores,accompanied by the formation of amorphous MNxshells;the tzbc ligands are insitu carbonized to form outermost N-doped carbon（NC）layers that connect with inner MNxvia M-N-C motifs inherited from the complex precursors and inhibit the transition of MNxfrom amorphous to crystalline phase.The Co@CoNx@NC-NG catalyst exhibits excellent HER activity with small overpotentials of 45 and 64 mV at a cathode current density of 10 mA·cm-2and low Tafel slopes of 40 and 85 mV·dec-1in 0.5 mol·L-1H2SO4and1.0 mol·L-1KOH electrolytes,respectively.The Co@CoNx@NC-NG retains 97% of the initial overpotential after 100,000 s in both acidic and alkaline media.Such outstanding HER performance originates from the crystalline-amorphous Co@CoNxthat redistributes electrons around the heterointerfaces,facilitating the conversion process of H+/H2O to hydrogen and thereby promoting HER kinetics.The outermost NC layers serve as the armor of Co@CoNx,and graphene nanosheets act as carriers of egg-like Co@CoNx@NC and conduction paths for electron shuttles,ensuring stable and continuous electrocatalytic hydrogen production.

关键词： Hydrogen evolution reaction Electrocatalysts Iron group metals Heterojunction Crystalline-amorphous structure

Three-stage niobium mineralization at Bayan Obo, China

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National Science Review 2024年第4期11卷 102-110页

作者： Yan Yu Yang Li Yu Liu xiao-xiao Ling Li-Guang Wu Li Yang Lan Yang Bo Yang Yong-Gang Zhao xian-Hua Li State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences College of Earth and Planetary Science University of Chinese Academy of Sciences Ministry of Education Key Laboratory of Orogenic Belts and Crustal Evolution School of Earth and Space SciencesPeking University Mining Research Institute Baotou Iron and Steel(Group) Co.LTD State Key Laboratory of Baiyunobo Rare Earth Resource Research and Comprehensive Utilization

The Chinese Bayan Obo deposit is a world-class rare earth element(REE) deposit with considerable niobium(Nb) and iron(Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead(U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites—key Nb-bearing minerals—are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma(n = 99), 438 ± 7 Ma(n = 93), and 268 ± 5 Ma(n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

关键词： niobium mineralization U-Pb dating ferrocolumbite Bayan Obo

First-principles study on the heterogeneous formation of environmentally persistent free radicals(EPFRs)overα-Fe2O3(0001)surface:Effect of oxygen vacancy

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Journal of Environmental Sciences 2024年第8期142卷 279-289页

作者： Wenxiao Pan Shuming He Qiao Xue xian Liu Jianjie Fu Kang xiao Aiqian Zhang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China School of Environment Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of SciencesHangzhou 310012China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Beijing Yanshan Earth Critical Zone National Research Station University of Chinese Academy of SciencesBeijing 101408China

Metal oxides with oxygen vacancies have a significant impact on catalytic activity for the transformation of organic pollutants in waste-to-energy(WtE)incineration processes.This study aims to investigate the influence of hematite surface oxygen point defects on the formation of environmentally persistent free radicals(EPFRs)from phenolic compounds based on the first-principles calculations.Two oxygen-deficient conditions were considered:oxygen vacancies at the top surface and on the subsurface.Our simulations indicate that the adsorption strength of phenol on theα-Fe_(2)O_(3)(0001)surface is enhanced by the presence of oxygen vacancies.However,the presence of oxygen vacancies has a negative impact on the dissociation of the phenol molecule,particularly for the surface with a defective point at the top layer.Thermo-kinetic parameters were established over a temperature range of300-1000 K,and lower reaction rate constants were observed for the scission of phenolic O-H bonds over the oxygen-deficient surfaces compared to the pristine surface.The negative effects caused by the oxygen-deficient conditions could be attributed to the local reduction of FeⅢto FeⅡ,which lower the oxidizing ability of surface reaction sites.The findings of this study provide us a promising approach to regulate the formation of EPFRs.

关键词： EPFR formation Phenol dissociation Oxygen-vacancy impact Hematite surface First-principles calculation

Recent advances in vacancy engineering for reliable lithiumsulfur batteries

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Rare Metals 2024年第2期43卷 455-477页

作者： Wen-Dong Liu xiao Tang Jun-An Feng Chao-Yue Zhang Hao Liu Chuan Shi xiao-xian Zhao Jian-Jun Song College of Physics School of Chemistry and Chemical EngineeringQingdao UniversityQingdao266071China Faculty of Science Centre for Clean Energy TechnologySchool of Mathematical and Physical SciencesUniversity of Technology SydneySydneyNSW2007Australia Department of Chemistry College of ScienceHebei Agricultural UniversityBaoding071001China

The high-energy-density and low-cost features endow lithium-sulfur batteries with broad application prospects.However,many drawbacks,especially the detrimental shuttle effect,have hindered the further development of LSBs.In response,a lot of new structures have been applied to suppress the shuttle effect and promote the development of LSBs.Recently,vacancy engineering has gained the attention of researchers due to its unique electronic structure.This review aims to analyze the application of vacancy engineering in LSBs.Firstly,the electrochemistry of LSBs has been systematically discussed and the existing challenges as well as improvement tactics of LSBs have also been presented.Subsequently,the preparation methods and characterization technologies of various vacancies are summarized,including oxygen vacancies,sulfur vacancies,selenium vacancies,other anion vacancies,cation vacancies,etc.The latest applications of vacancy engineering in LSBs are also summarized in this review.Finally,some prospects and insights for further investigation and practical application of vacancy engineering in LSBs are put forward.

关键词： Lithium-sulfur batteries(LSBs) Defects Vacancy engineering Electronic structure Shuttle effect

Prediction of suitable water content in granulation of sintering mixture based on Litster's model

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Journal of Iron and Steel Research(International) 2024年第3期31卷 552-560页

作者： Fang-lei Dai xiao-hui Fan xiao-xian Huang Xu-ling Chen Min Gan Zhi-yun Ji Zeng-qing Sun School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083HunanChina

Suitable water content plays a decisive role in the granulation of sintering mixtures.Herein,a method was proposed to predict the suitable water content for effective granulation on the basis of Litster's granulation model.The granulation effectiveness of a sintering mixture was predicted by the model,with the allowance error of±10%.The effects of the water absorption properties,particle size composition and content of adhesive particles on the suitable water content were studied.The results showed that the allowable error of prediction was within±0.5%compared to the experimentally determined suitable water content.With an increase in adhesive powder content of mixtures with higher water absorption,the suitable water content increased to achieve similar granulation effectiveness.Moreover,as the amount of concentrates increased,the suitable water content first increased and then remained steady.The influence of the water absorption characteristics of the adhesive particles on the suitable water content was less than that of their particle size composition in the mixture.

关键词： Adhesive particle Sintering mixture Granulation effectiveness Suitable water content

A micro-crosslinked amphoteric hydrophobic association copolymer as high temperature-and salt-resistance fluid loss reducer for water-based drilling fluids

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Petroleum Science 2024年第3期21卷 1980-1991页

作者： Jian Li Yu-Xi Ji xiao-xiao Ni Kai-He Lv xian-Bin Huang Jin-Sheng Sun School of Petroleum Engineering China University of Petroleum(East China) Key Laboratory of Unconventional Oil & Gas Development China University of Petroleum(East China) Inspection and Testing Center of Huabei Oil Field Company PetroChina Drilling Fluid Research Institute CNPC Engineering Technology R&D Company Limited

During ultradeep oil and gas drilling, fluid loss reducers are highly important for water-based drilling fluids, while preparing high temperature-and salt-resistance fluid loss reducers with excellent rheology and filtration performance remains a challenge. Herein, a micro-crosslinked amphoteric hydrophobic association copolymer(i.e., DADC) was synthesized using N,N-dimethyl acrylamide, diallyl dimethyl ammonium chloride, 2-acrylamido-2-methylpropane sulfonic acid, hydrophobic monomer, and pentaerythritol triallyl ether crosslinker. Due to the synergistic effects of hydrogen bonds, electrostatic interaction, hydrophobic association, and micro-crosslinking, the DADC copolymer exhibited outstanding temperature-and salt-resistance. The rheological experiments have shown that the DADC copolymer had excellent shear dilution performance and a certain degree of salt-responsive viscosity-increasing performance. The DADC copolymer could effectively adsorb on the surface of bentonite particles through electrostatic interaction and hydrogen bonds, which bring more negative charge to the bentonite, thus improving the hydration and dispersion of bentonite particles as well as the colloidal stability of the drilling fluids. Moreover, the drilling fluids constructed based on the DADC copolymer exhibited satisfactory rheological and filtration properties(FLHTHP= 12 m L) after aging at high temperatures(up to200°C) and high salinity(saturated salt) environments. Therefore, this work provided new insights into designing and fabricating high-performance drilling fluid treatment agents, demonstrating good potential applications in deep and ultradeep drilling engineering.

关键词： Fluid loss reducer Temperature- and salt-resistance Hydrophobic association Amphoteric Micro-crosslinking

Comprehensive analysis and mitigation strategies for safety issues of sodium-ion batteries

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Rare Metals 2024年第4期43卷 1343-1349页

作者： Tao Wei xiao-Ling xian Shi-Xue Dou Wei Chen Shu-Lei Chou Institute for Carbon Neutralization College of Chemistry and Materials EngineeringWenzhou University Wenzhou Key Laboratory of Sodium-Ion Batteries Wenzhou University Technology Innovation Institute for Carbon Neutralization Zhejiang Key Laboratory of Carbon Materials College of Chemistry and Materials EngineeringWenzhou University Institute for Superconducting and Electronic Materials Australian Institute for Innovative MaterialsUniversity of WollongongInnovation Campus

Sodium-ion batteries show great potential as an alternative energy storage system,but safety concerns remain a major hurdle to their mass adoption.This paper analyzes the key factors and mechanisms leading to safety issues,including thermal runaway,sodium dendrite,internal short circuits,and gas release.Several promising solutions are proposed,such as high-safety electrode materials in the cathode and anode,high-safety electrolytes,and external battery management systems.Here in also we emphasize the importance of selecting appropriate analysis methods and developing reliable failure models while suggesting advanced machine learning tools for analysis.With a comprehensive approach,this study offers valuable recommendations to optimize materials and solutions for improving the safety of sodium-ion batteries.

关键词： Sodium-ion batteries Safety issues Thermal runaway Sodium dendrites

Fluoro-functionalized plant biomass adsorbent:Preparation and application in extraction of trace perfluorinated compounds from environmental water samples

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Journal of Environmental Sciences 2024年第3期137卷 703-715页

作者： Xi Tan Yan Shi Chun-Feng Ma Quan Chi Yu-Hang Yang Wen-xiang Zhang Hua-Ming xiao xian Wang Key Laboratory of Analytical Chemistry of the State Ethnic Affairs Commission School of Chemistry and Materials ScienceSouth-Central Minzu UniversityWuhan 430074China School of Pharmaceutical Sciences South-Central Minzu UniversityWuhan 430074China Key Laboratory of Oilseeds Processing of Ministry of Agriculture Hubei Key Laboratory of Lipid Chemistry and NutritionOil Crops Research Institute of the Chinese Academy of Agricultural SciencesWuhan 430062China

Perfuorinated compounds(PFCs)are toxic and widely present in the environment,and therefore effective adsorbents are required to remove PFCs from environmental water.In the present study,a new type of fuorinated biomass materials was synthesized via an ingenious fuorosilanization reaction.These adsorbents were applied for the adsorption of 13typical PFCs,including perfuorocarboxylic acids(PFCAs)and perfuorosulfonic acids(PFSAs).By comparing their adsorption performance,Fluorinated cedar slag(FCS)was discovered to have the best absorption efficiency and enabled highly efficient enrichment of PFCs.The adsorption recovery of FCS with the investigated PFCs is greater than 90%under the optimal adsorption condition.Ascribed to the high affinity of F-F sorbent-sorbate interaction,FCS had good adsorption capacities of PFCs from aqueous solution,with the maximum adsorption capacity of 15.80 mg/g for PFOS and 10.71 mg/g for PFOA,respectively.Moreover,the adsorption time could be achieved in a short time(8 min).Using the FCS absorbent,an innovative FCS-solid phase extraction assisted with high performance liquid chromatography-electrospray-tandem mass spectrometry(FCS-SPE-HPLC-ESI-MS/MS)method was first developed to sensitively detect PFCs in the environmental water samples.The intra-day and inter-day recovery rates of the 13 compounds ranged from 90.7%-104.3%,with the RSD of 2.1%-4.7%(intra-day)and 2.5%-8.5%(inter-day),respectively.This research demonstrates the potential of the newly fuoro-functionalized plant biomass to adsorb PFCs from environmental water,with the advantages of high adsorption efficiencies,high antiinterference,easy operation and low economic cost.

关键词： Fluoro-functionalized biomass Perfuorinated compounds(PFCs) Adsorption efficiency Mass spectrometry(MS) Fluorinated cedar slag(FCS)