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Chinese Journal of Structural Chemistry 2022年第9期41卷 87-93页

作者： Zhao-Di Zhou Zi-Long Xu Dan Wang lin-Fang Jia Han-Qing Zhao Bao-Yi yu chong-Chen Wang Key Laboratory of Urban Agriculture(North China) Ministry of AgricultureCollege of Bioscience and Resources EnvironmentBejing University of AgricultureBejing102206China Beijing Key Laboratory of Functional Materials for Building Structure and Environment Remediation Bejing University of Civil Engineering and ArchitectureBeijing 100044China

Two coordination polymers(CPs) [Zn(PTA)(DTP)(HO)]·(DMF)(CP-1) and [Zn(BTC)(DTP)]·(CHCN)·(HO)(CP-2) with one-and two-dimensional architectures were synthesized from Zn(Ⅱ) ion and different organic linkers like terephthalic acid(HPTA), benzene-1,3,5-tricarboxylic acid(HBTC), and 3,5-di(1,2,4-triazol-1-yl) pyridine(DTP). The fluorescent sensing experiments showed that the two CPs displayed effective, sensitive, and selective abilities towards Feand CrO. For sensing the pesticides, CP-1 outperforms in sensing of metamitron(MMT) and CP-2 is ultrasensitive towards imidacloprid(IMI). The possible mechanisms involved in the quenching of the fluorescence intensity include the inner filter effect(IFE) and the fluorescence resonance energy transfer(FRET) effect.

关键词： coordination polymer fluorescence sensing heavy metal ions pesticides X-ray crystallography

Unraveling the significance of cobalt on transformation kinetics,crystallography and impact toughness in high-strength steels

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 380-390页

作者： Yishuang yu Jingxiao Zhao Xuelin Wang Hui Guo Zhenjia Xie Chengjia Shang Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China School of Materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

This work reveals the significant effects of cobalt(Co)on the microstructure and impact toughness of as-quenched highstrength steels by experimental characterizations and thermo-kinetic *** results show that the Co-bearing steel exhibits finer blocks and a lower ductile-brittle transition temperature than the steel without ***,the Co-bearing steel reveals higher transformation rates at the intermediate stage with bainite volume fraction ranging from around 0.1 to *** improved impact toughness of the Co-bearing steel results from the higher dense block boundaries dominated by the V1/V2 variant ***,the addition of Co induces a larger transformation driving force and a lower bainite start temperature(BS),thereby contributing to the refinement of blocks and the increase of the V1/V2 variant *** findings would be instructive for the composition,microstructure design,and property optimization of high-strength steels.

关键词： high-strength steel cobalt transformation kinetics crystallography impact toughness

Controlled synthesis and closed-loop chemical recycling of biodegradable copolymers with composition-dependent properties

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Science China Chemistry 2022年第5期65卷 943-953页

作者： Yi-Teng Yan Gang Wu Si-chong Chen yu-Zhong Wang The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MoE) National Engineering Laboratory ofEco-Friendly Polymeric Materials(Sichuan)State Key Laboratory of Polymer Materials EngineeringCollege of ChemistrySichuan UniversityChengdu 610064China

The closed-loop recycling concept of the polymer wastes into building-block chemicals is attractive,but the closed-loop recycling of copolymers enabled by energy-efficient chemical recycling and cost-effective separations is still facing great ***,for the first time,a one-pot sequential copolymerization of γ-butyrolactone(γ-BL) and p-dioxanone(PDO)using an economical ureas/alkoxides catalytic system is conducted to synthesize biodegradable and chemically recyclable poly-(γ-butyrolactone)-block-poly(p-dioxanone)(PγBL-b-PPDO) diblock copolymers with well-defined and controlled *** composition-dependent properties of PγBL-b-PPDO copolymers,including thermal properties and crystallization behavior,are *** results show that the thermal stability and crystalline ability of PγBL are enhanced observably by introducing the PPDO ***,the PγBL-b-PPDO copolymers can be depolymerized efficiently into the corresponding co-monomers with a yield of over 95% by simply low-temperature pyrolysis under ***,γ-BL and PDO monomers are selectively separated with an isolated purity of about 99% based on the difference in their physicochemical ***,their repolymerization is realized to obtain the copolymers with nearly identical structures and thermostability,demonstrating the closed-loop recycling of copolymers,i.e.,*** research provides important guidance for the design of novel sustainable polymers towards more efficient chemical recycling,separation and regeneration.

关键词： biodegradable copolyester poly(p-dioxanone) tunable properties closed-loop chemical recycling

Chemically recyclable copolyesters from bio-renewable monomers:controlled synthesis and composition-dependent applicable properties

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Science China Chemistry 2023年第7期66卷 2062-2069页

作者： Wan-Ting Xiong Gang Wu Si-chong Chen yu-Zhong Wang The Collaborative Innovation Center for Eco-Friendly and Fire-Safety Polymeric Materials(MoE) National Engineering Laboratory of Eco-Friendly Polymeric Materials(Sichuan)State Key Laboratory of Polymer Materials EngineeringCollege of ChemistrySichuan UniversityChengdu 610064China

The development of chemically recyclable polymers is a promising solution to address the dual challenges of the environment and resources caused by petroleum-based *** recent advancements,it is highly desirable for developing recyclable polymers to meet the requirements of both practical uses and well-performed ***-renewable monomers have been paid great attention recently as promising potential candidates for establishing a sustainable circular polymer ***,a sequential copolymerization of various bio-renewable n-alkyl substituted δ-valerolactone((R)VLs)and p-dioxanone(PDO)is conducted to synthesize novel chemically recyclable diblock copolymers poly(p-dioxanone)-block-poly(n-alkyl-valerolactones)(PPDO-b-P(R)VLs)with well-defined and controlled *** properties of copolymers including thermal property,crystallization,mechanical property,hydrophilicity and transport property can be tuned effectively to meet the requirements of practical uses by alternating the alkyl substituents(R)and the P(R)VLs *** addition,the high-efficiency and facile chemical recycling of copolymers to PDO and(R)VL comonomers is realized with a high yield of>96.5%and a high purity of 99%.

关键词： bio-renewable monomers ring-opening polymerization block copolyester tunable properties chemical recyclability

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A remote sensing monitoring method for alpine grasslands desertification in the eastern Qinghai–Tibetan Plateau

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Journal of Mountain Science 2020年第6期17卷 1423-1437页

作者： KUANG Qian yuAN Quan-zhi HAN Ji-chong LENG Rong WANG yu-shuang ZHU Ke-hong lin Shuo REN Ping Key Laboratory of Land Resources Evaluation and Monitoring in Southwest Ministry of EducationSichuan Normal UniversityChengdu 610068China Institute of Geography and Resources Science Sichuan Normal UniversityChengdu 610068China Key Laboratory of Environmental Change and Natural Disaster MOE/State Key Laboratory of Earth Surface Processes and Resources EcologyFaculty of Geographical ScienceAcademy of Disaster Reduction and Emergency ManagementBeijing Normal UniversityBeijing 100875China Department of Engineering Physics Tsinghua UniversityBeijing 100084China Collge of Resources Sichuan Agricultural UniversityChengdu 611130China

Alpine grassland is the typical vegetation in the eastern Qinghai–Tibetan Plateau,which has important ecological service functions,and also supports the development of alpine stock *** recent years,under both the natural and human disturbance,alpine grasslands in this area have appeared to different degrees of desertification.A diagnosis of the desertification degree serves as the basis for grassland ecological *** study constructs a comprehensive index based on remote sensing called alpine grassland desertification index(AGDI)to monitor the areas and degree of *** most relevant indicators of desertification,namely,vegetation fraction,aboveground biomass,soil moisture,and land surface temperature,were selected to establish *** geographical detector is used to reselect and assess these *** results show that the overall verification accuracy of AGDI is 82.05%.In particular,the accuracy of identifying severe desertification is the *** study confirms that the desertification of alpine grasslands in the eastern Qinghai–Tibetan Plateau is characterized by ***,Landsat-8 OLI data with a spatial resolution of 30 m is more suitable than MODIS data for alpine grasslands desertification *** research results can provide a methodological reference for monitoring desertification of alpine grasslands and other grassland regions in the world.

关键词： Desertification monitoring Alpine grassland desertification index(AGDI) Geographical detector Zoige county

Firm-level Strategic Competition and Peer Effects in Corporate Investment among Chinese Firms

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Journal of Systems Science and Systems Engineering 2022年第6期31卷 753-774页

作者： Jianing Li yu-En lin School of Business Administration Northeastern UniversityShenyangLiaoning110000China Center for Quantitative Economics Jilin UniversityChangchunjilin130015China

This study investigates the influence of strategic competition on peer effects in corporate investment by using a sample of 28,522 observations of Chinese listed companies from 2008 to *** study develops a linear-in means model and uses an instrumental variables approach,and uses the competitive strategy measure(CSM)and Lerner index as proxies of competitive strategies and competitive positions to capture the firm-level *** empirical results demonstrate that when firms compete as strategic substitutes and when firms are in higher competitive positions,the peer effects in corporate investment are significant and *** addition,in circumstances of high information asymmetry,firms competing as strategic substitutes and firms in high competitive positions rely more on information related to investment from peer ***,industry policies and barriers do not significantly influence peer effects in *** study offers new empirical evidence regarding peer effects in corporate investment in China.

关键词： Corporate investment peer effects competitive strategy competitive position

基于O'NET半结构化访谈建构大学生职业适应力故事

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高校辅导员学刊 2025年第1期17卷 34-42,97页

作者：林振余权肖龙福建商学院传媒与会展学院福建福州350012

职业适应力是大学生转型为职场人士的关键能力,其中职业兴趣是核心要素。然而,当前对大学生职业兴趣的分析主要局限于定量评估,导致学生对自身职业兴趣的理解较为表面,甚至开始怀疑其价值。研究采用O'NET半结构化访谈,结合主题演绎驱动... 详细信息

职业适应力是大学生转型为职场人士的关键能力,其中职业兴趣是核心要素。然而,当前对大学生职业兴趣的分析主要局限于定量评估,导致学生对自身职业兴趣的理解较为表面,甚至开始怀疑其价值。研究采用O'NET半结构化访谈,结合主题演绎驱动理论,深入分析了大学生在职业适应力故事中的关注、控制、好奇、自信、合作五个维度,旨在探讨半结构化访谈如何定性地将职业兴趣代码与这五个维度的故事关联起来,并揭示其在提升大学生职业适应力方面的作用。研究结果显示,通过半结构化访谈建构的职业适应力故事,成功整合了定量与定性职业兴趣评估,这种方法不仅能帮助大学生更深入地理解自身的霍兰德职业兴趣代码,还能促使他们系统地叙述职业适应力故事,从而有效提升其职业适应力。

关键词：故事建构半结构化访谈职业适应力定性 O'NET

Chlorine-rich lithium argyrodites enables superior performances for solid-state Li-Se batteries at wide temperature range

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Rare Metals 2022年第12期41卷 4065-4074页

作者： Jin-Yan lin Shuai Chen Jia-Yang Li Dian yu Xiang-ling Xu Chuang yu Shao-Qing Chen Xue-Fei Miao lin-Feng Peng Chao-Chao Wei chong-Xuan Liu Shi-Jie Cheng Jia Xie State Key Laboratory of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Materials Huazhong University of Science and TechnologyWuhan 430074China Department of Materials Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Key Laboratory of Advanced Metallic and Intermetallic Materials Technology School of Materials Science and EngineeringNanjing University of Science and TechnologyNanjing 210094China School of Environmental Science and Engineering Southern University of Science and TechnologyShenzhen 518055China

All-solid-state Li-Se battery shows great potential as a candidate for next-generation energy storage devices due to its high energy density and ***,the low ionic conductivity of the solid electrolytes and large volume changes of Se active materials are two of the major issues that limit its ***,a simple solid-state reaction method is applied to synthesize chlorine-rich argyrodite Li_(5.5)PS_(4.5)CI_(1.5)electrolyte with high conductivity of 6.25 mS·cm^(-1)at room *** nanotube(CNT)is introduced as the host for Se to obtain Se/CNT composite with both enhanced electronic conductivity and lower volume expansion during the electrochemical reaction ***-solid-state Li-Se battery using Li_(5.5)PS_(4.5)CI_(1.5)as solid electrolyte combined with Se/CNT cathode and Li-In anode shows a discharge capacity of 866 mAh·g-1for the 2nd cycle under0.433 mA·cm-2at room ***,the assembled battery delivers a high discharge capacity of1026 mAh·g^(-1)for the 2nd cycle when cycled at the same current density at 60℃and maintains a discharge capacity of 380 mAh·g^(-1)after 150 *** to the high Li-ion conductivity of Li_(5.5)PS_(4.5)CI_(1.5)electrolyte,the assembled battery displays a high discharge capacity of 344 mAh·g^(-1)under 0.113 mA·cm^(-2)at-20℃C and remains 66.1%after200 *** addition,this all-solid-state Li-Se battery shows ultralong cycling performances up to 1000 cycles under 0.433 mA·cm^(-2)at-20℃.This work offers the design clue to fabricate the all-solid-state Li-Se battery workable at different operating temperatures with an ultralong cycling life.

关键词： Lithium argyrodite Chlorine-rich All-solidstate Li-Se batteries Operating temperatures Long cycling performances

Microstructure and mechanical properties of a hot-extruded Al-based composite reinforced with core–shell-structured Ti/Al3Ti

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International Journal of Minerals,Metallurgy and Materials 2017年第12期24卷 1431-1437页

作者： Li Zhang Bao-lin Wu yu-lin Liu School of Materials Science and Engineering Shenyang Aerospace UniversityShenyang 110136China Liaoning Key Laboratory of Aviation Light Alloy and Processing Technology Shenyang Aerospace UniversityShenyang 110136China

An Al-based composite reinforced with core–shell-structured Ti/Al_3Ti was fabricated through a powder metallurgy route followed by hot extrusion and was found to exhibit promising mechanical properties. The ultimate tensile strength and elongation of the composite sintered at 620°C for 5 h and extruded at a mass ratio of 12.75:1 reached 304 MPa and 14%, respectively, and its compressive deformation reached 60%. The promising mechanical properties are due to the core–shell-structured reinforcement, which is mainly composed of Al_3Ti and Ti and is bonded strongly with the Al matrix, and to the reduced crack sensitivity of Al_3Ti. The refined grains after hot extrusion also contribute to the mechanical properties of this composite. The mechanical properties might be further improved through regulating the relative thickness of Al–Ti intermetallics and Ti metal layers by adjusting the sintering time and the subsequent extrusion process.

关键词： microstructure aluminum-based composites Ti/Al3Ti reinforcements mechanical properties

Acidogenic sludge fermentation to recover soluble organics as the carbon source for denitrification in wastewater treatment： Comparison of sludge types

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Frontiers of Environmental Science & Engineering 2018年第4期12卷 25-32页

作者： lin lin Ying-yu Li Xiao-yan Li Environmental Engineering Research Centre Departmelt of Civil Engineering The University of Hong Kong Pokfulam Hong Kong China Shenzhen Engineering Research Laboratory for Sludge and Food Waste Treatment and Resource Recovery Graduate School at Shenzhcn Tsinghua University Shcnzhen 518055 China＊

For biological nitrogen （N） removal from wastewater, a sufficient organic carbon source is requested fbr denitrification. However. the organic carbon/nitrogen ratio in municipal wastcwatcr is becoming lower in recent years, which increases the demand for the addition of external organic carbon, e.g. methanol, in wastewater treatment. The volatile fatty acids （VFAs） produced by acidogenic fenncntation of sewage sludge can be an attractive alternative for methanol. Chemically enhanced primary sedimentation （CEPS} is an effective process that applies chemical coagulants to enhance the removal of organic pollutants and phosphorus from wastewater by sedimentation. In temls of the chemical and biological characteristics, the CEPS sludge is considerably different from the conventional primary and secondary sludge. In the present study, FeCI3 and PACI （polyalunfinum chloride） were used as the coagulants for CEPS treatment of raw sewage. The derived CEPS sludge （Fe-sludge and Al-sludge） was then processed with mcsophilic acidogenic fennentation to hydrolysc the solid organics and produce VFAs for organic carbon recovery, and the sludge acidogenesis efficiency was compared with that of the conventional primary sludge and secondary sludge. The results showed that the Fe-sludge exhibited the highest hydrolysis and acidogenesis efficiency, while the Al-sludge and secondary＇ sludge had lower hydrolysis efficiency than that of primary sludge. Utilizing ffie Fc-sludgc fermentation liquid as tbc carbon source for denitrificatiom more than 99%of nitrate removal was achieved in the main-stream wastewater treatment without any external carbon addition, instead of 35% obtained from the conventional process of primary sedimentation followed by the oxic/anoxic （O/A） treatment.

关键词： Sewage sludge Chemically enhanced primary sedimentation(CEPS) Acidogenic fermentation Organic carbon recovery Nitrogen removal