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Chemical Research in Chinese Universities 2019年第3期35卷 485-489页

作者： zhao Shengxiang zhao Ying XING Xiaoling JU Xuehai Xi'an Modem Chemistry Research Institute Xi 'an 710065P.R.China School of Chemical Engineering Nanjing University of Science and Technology Nanjing 210094P.R.China

density functional theory calculations at the B3LYP/6-31+G^** and B3LYP/6-311++G ^** levels were perfonned on thermal decomposition of 5,5′-bis(tetrazole)-1 ,r-diolate(TKX-50) anion with an intramolecular oxygen transfer being an initial step. Tlie results show that the intramolecular oxygen transfers are the rate-limiting steps for the decomposition of title anion with activation energies being in the range of 287-328 kJ/mol. Judged by the nucleus- independent chemical shift values, the formation of antiaromatic ring in transition state or the decrease of aromaticity of the tetrazole ring of the reactant makes somewhat contribution to the high potential energies of the rate-limiting transition states. However, the activation energies of the following N2 elimination tlirough various pathways are in a low range of 136-166 kJ/mol. The tetrazole ring acts as an electron donor or acceptor in difierent pathways to assist the bond nipture or group elimination. The rate constants in a temperature range of 500-2000 K for all the intramolecular oxygen transferring reactions were obtained. The corresponding linear relationships between InA and 1/T were established.

关键词： Thennal decomposition 5,5′-Bis(tetrazole)-1,1′-diolate(TKX-50) anion Activation energy barrier density functional theory

Sesquiterpenoids and an ergosterol from cultures of the fungus Daedaleopsis tricolor

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Natural Products and Bioprospecting 2013年第6期3卷 271-276页

作者： Jiang-Yuan zhao Tao feng Zheng-Hui LI Ze-Jun DONG Hong-Bin ZHANG Ji-Kai LIU State Key Laboratory of Phytochemistry and Plant Resources in West China Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China Key Laboratory of Medicinal Chemistry for Natural Resources Ministry of EducationSchool of Chemical Science and TechnologyYunnan UniversityKunming 650091China

Four new bisabolane sesquiterpenoids daedatrins A-D(1-4),a cadinane sesquiterpene 12-hydroxy-α-cadinol(5),and a heptanorergosterane derivative daedatrin G(6)were isolated from cultures of the basidiomycete Daedaleopsis *** structures were elucidated by spectroscopic methods including extensive 2D NMR techniques and X-ray *** the compounds showed no significant activity against five human cancer cell lines.

关键词： Daedaleopsis tricolor sesquiterpenoid ergosterane

Photothermal-controlled sustainable degradation of protective coating modified Mg alloy using near-infrared light

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Rare Metals 2021年第9期40卷 2538-2551页

作者： Zhi-Xin Han Xiang-Mei Liu Lei Tan zhao-Yang Li Yu-feng Zheng Kelvin Wai-Kwok Yeung Zhen-Duo Cui Yan-Qin Liang Sheng-Li Zhu Shui-Lin Wu Hubei Key Laboratory of Polymer Materials Ministry-of-Education Key Laboratory for the Green Preparation and Application of Functional MaterialsSchool of Materials Science&EngineeringHubei UniversityWuhan 430062China The Key Laboratory of Advanced Ceramics and Machining Technology by the Ministry of Education of China School of Materials Science&EngineeringTianjin UniversityTianjin 300072China State Key Laboratory for Turbulence and Complex System Department of Materials Science and EngineeringCollege of EngineeringPeking UniversityBeijing 100871China department of Orthopaedics and Traumatology Li Ka Shing Faculty of MedicineThe University of Hong KongPokfulam 999077Hong KongChina

Controlling the corrosion rate is critical for practical applications of Mg-based alloys. In this work, we constructed a protective coating of hybrid polycaprolactone(H-PCL)/indocyanine green(ICG) on AZ31 Mg alloy,whose degradation rate was controlled by 808-nm nearinfrared(NIR) light irradiation. The corrosion behaviors of H-PCL/ICG coated Mg alloys were systematically investigated by potentiodynamic polarization tests, electrochemical impedance spectroscopy(EIS) and hydrogen evolution experiments. The results disclosed that the H-PCL/ICG composite coating could effectively protect Mg alloy from corroding without NIR light irradiation. In contrast, under 808-nm NIR light irradiation, the corrosion resistance of this composite coating was decreased significantly, i.e., the corrosion current density(i_(corr))increasedfrom(8.81 ± 1.068) 9 10^(-8) to(1.22 ± 0.545) 9 10^(-6) A·cm^(-2). This is because the component of ICG in the coating was excited to produce heat locally, which triggered the glass transition temperature(T_(g)) of H-PCL in the coating, resulting in the motion of the molecular chain segment. Consequently, the electrolytes penetrated the coating and corroded the Mg substrate. In vitro biological experiment indicated that the synthesized coating exhibited good ***, these findings will provide a new strategy for designing novel photoresponsive coatings to remotely adjust the degradation rate of biodegradable metals for biomedical applications.

关键词： Magnesium Corrosion Coating Photoresponsive Surface modification

Single Zn atoms anchored on hollow carbon nanofiber network for dendrite-free lithium metal anode of flexible Li–S full cell

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Rare Metals 2023年第11期42卷 3705-3717页

作者： Zhi-feng Wang Hong-Ying Wang Xiao-Li Liu Yan-Xu Chen Yan zhao Yong-Guang Zhang Qi-Qi Han Chun-Ling Qin Zhumabay Bakenov Yi-Chao Wang Xin Wang School of Materials Science and Engineering Hebei University of TechnologyTianjin300401China School of Materials Science and Engineering Hebei University of Science and TechnologyShijiazhuang050018China South China Academy of Advanced Optoelectronics and International Academy of Optoelectronics at zhaoqing South China Normal UniversityGuangzhou510006China Shanxi Supercomputing Center Lvliang033000China department of Chemical and Materials Engineering National Laboratory AstanaNazarbayev University010000Nur-SultanKazakhstan School of Life and Environmental Sciences Deakin UniversityWaurn PondsGeelongVIC3216Australia

The attractive energy density of lithium-sulfur(Li-S)batteries makes them desirable energy storage systems;however,the slow reaction kinetics and formation of lithium dendrites prevent them from reaching full *** address this issue,hierarchical porous carbon nanofibers network containing Zn single atoms(ZnSA@HPCNF)is synthesized by electrospinning and *** structure serves as the main anode body,providing excellent chemical anchoring and *** uniform distribution of Zn single atoms and N4coordination supports uniform deposition and continuous plating/stripping of *** results show that the Li|Li/ZnSA@HPCNF symmetrical battery presents stable and low overpotential during 700-and 900-h iterative plating/stripping process at1 and 5 mA·cm^(-2),***,the S/CNT||Li/ZnSA@HPCNF full cell shows good flexibility,reversible capacity and cycling *** work provides a lithium host strategy based on single-atom dispersed hierarchical porous carbon network,enabling the design of rational lithium metal anodes for use in flexible Li-S full cells.

关键词： Single atom Lithium metal anode Lithium deposition Lithium-sulfur battery

Time-Variant Consensus Tracking Control for Networked Planar Multi-Agent Systems with Non-Holonomic Constraints

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Journal of Systems Science & Complexity 2018年第2期31卷 396-418页

作者： zhao Jun LIU Guo-Ping Center for Control Theory and Guidance Technology Harbin Institute of Technology Harbin 150080 China School of Engineering University of South Wales Pontypridd CF37 1DL United Kingdom.

A time-variant consensus tracking control problem for networked planar multi-agent systems with non-holonomic constraints is investigated in this paper. In the time-variant consensus tracking problem, a leader agent is expected to track a desired reference input, simultaneously, follower agents are expected to maintain a time-variant formation. To solve the time-variant consensus tracking problem of planar multi-agent systems with non-holonomic constraints, a time-variant consensus tracking control strategy is designed on the basis of an unidirectional topology structure. One of main contributions of this paper is the time-variant consensus tracking protocol for general time-variant formations of planar multi-agent systems with non-holonomic constraints, the other main contribution of this paper is an active predictive control strategy, where predictions of agents are generated actively, so that the computational efficiency is improved than passive approaches. The proposed control strategy is verified by two types of time-varying formations of wheeled mobile robots, and the experimental results show that the proposed control strategy is effective for general time-variant consensus tracking problems of planar multi-agent systems with non-holonomic constraints in local and worldwide networked environments.

关键词： Consensus tracking networked multi-agent system networked predictive control nonholonomic constraint time-variant consensus.

Gapless genome assembly of azalea and multi-omics investigation into divergence between two species with distinct f lower color

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Horticulture Research 2023年第1期10卷 193-206页

作者： Shuai Nie Shi-Wei zhao Tian-Le Shi Wei zhao Ren-Gang Zhang Xue-Chan Tian Jing-Fang Guo Xue-Mei Yan Yu-Tao Bao Zhi-Chao Li Lei Kong Hai-Yao Ma zhao-Yang Chen Hui Liu Yousry AEl-Kassaby Ilga Porth Fu-Sheng Yang Jian-feng Mao National Engineering Research Center of Tree Breeding and Ecological Restoration Beijing Advanced Innovation Center for Tree Breeding by Molecular DesignKey Laboratory of Genetics and Breeding in Forest Trees and Ornamental PlantsMinistry of EducationCollege of Biological Sciences and TechnologyBeijing Forestry UniversityBeijing 100083China department of Ecology and Environmental Science UmeåPlant Science CentreUmeåUniversitySE-90187 UmeåSweden department of Bioinformatics Ori(Shandong)Gene Science and Technology Co.Ltd.Weifang 261322China department of Forest and Conservation Sciences Faculty of ForestryUniversity of British ColumbiaVancouverBCV6T 1Z4Canada Départment des Sciences du Bois et de la Forêt Facultéde Foresteriede Géographie et GéomatiqueUniversitéLavalQuébecQCG1V 0A6Canada State Key Laboratory of Systematic and Evolutionary Botany Institute of BotanyChinese Academy of SciencesBeijing 100093China University of Chinese Academy of Sciences Beijing 100049China

The genus Rhododendron(Ericaceae),with more than 1000 species highly diverse in f lower color,is providing distinct ornamental values and a model system for f lower color ***,we investigated the divergence between two parental species with different f lower color widely used for azalea *** genome assembly was generated for the yellow-f lowered azalea,Rhododendron *** genomics found recent proliferation of long terminal repeat retrotransposons(LTR-RTs),especially Gypsy,has resulted in a 125 Mb(19%)genome size increase in species-specific regions,and a significant amount of dispersed gene duplicates(13402)and pseudogenes(17437).Metabolomic assessment revealed that yellow f lower coloration is attributed to the dynamic changes of carotenoids/f lavonols biosynthesis and chlorophyll ***-ordered gene co-expression networks(TO-GCNs)and the comparison confirmed the metabolome and uncovered the specific gene regulatory changes underpinning the distinct f lower pigmentation.B3 and ERF TFs were found dominating the gene regulation of carotenoids/f lavonols characterized pigmentation in ***,while WRKY,ERF,WD40,C2H2,and NAC TFs collectively regulated the anthocyanins characterized pigmentation in the red-f lowered R *** study employed a multi-omics strategy in disentangling the complex divergence between two important azaleas and provided references for further functional genetics and molecular breeding.

关键词： divergence yellow collective

Rhubarb Antagonizes Matrix Metalloproteinase-9-induced Vascular Endothelial Permeability

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Chinese Medical Journal 2016年第14期129卷 1737-1743页

作者： Yun-Liang Cui Sheng Zhang zhao-Tao Tian zhao-Fen Lin de-Chang Chen department of Critical Care Medicine Jinan Military General Hospital Jinan Shandong 250031 China department'of Emergency Medicine Changzheng Hospital Second Militaiy Medical University-Shanghai 200003 China

Background： Intact endothelial structure and function are critical for maintaining microcirculatory homeostasis. Dysfunction of the latter is an underlying cause of various organ pathologies. In a previous study, we showed that rhubarb, a traditional Chinese medicine, protected intestinal mucosal microvascular endothelial cells in rats with metastasizing septicemia. In this study, we investigated the effects and mechanisms of rhubarb on matrix metalloproteinase-9 （MMP9）-induced vascular endothelial （VE） permeability. Methods： Rhubarb monomers were extracted and purified by a series of chromatography approaches. The identity of these monomers was analyzed by hydrogen-1 nuclear magnetic resonance （NMR）, carbon-13 NMR, and distortionless enhancement by polarization transfer magnetic resonance spectroscopy. We established a human umbilical vein endothelial cell （HUVEC） monolayer on a Transwell insert. We measured the HUVEC permeability, proliferation, and the secretion of VE-cadherin into culture medium using fluorescein isothiocyanate-dextran assay, 3-（4,5-dimethyl-2-thiazolyl）-2,5-diphenyl-2-H-tetrazolium bromide assay, and enzyme-linked immunosorbent assay, respectively, in response to treatment with MMP9 and/or rhubarb monomers. Results： A total of 21 rhubarb monomers were extracted and identifed. MMP9 significantly increased the permeability of the HUVEC monolayer, which was significantly reduced by five individual rhubarb monomer （emodin, 3,8-dihydroxy- 1-methyl-anthraquinone-2-carboxylic acid, 1-O-caffeoyl-2-（4-hydroxyl-O-cinnamoyl）-β-D-glucose, daucosterol linoleate, and rhein） or a combination of all five monomers （1μmol/L for each monomer）. Mechanistically, the five-monomer mixture at 1 μmol/L promoted HUVEC proliferation. In addition, MMP9 stimulated the secretion of VE-cadherin into the culture medium, which was significantly inhibited by the five-monomer mixture. Conclusions： The rhubarb mixture ofemodin, 3,8-dihydroxy-l-methyl-anthraquinone-2-carboxylic ac

关键词： Matrix Metalloproteinase-9 Monomer Peneability Rhubarb Vascular Endothelial-cadherin: Vascular Endothelial Cell

The Fabrication of Microstructure Surface of Superhydrophobic Coating by Surface Gelation Technology

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Journal of Wuhan University of Technology(Materials Science) 2008年第2期23卷 163-165页

作者： DUAN Hui WANG Houzhi zhao Lei zhao Huizhong The Hubei Province Ministry-province Jointly-constructed Cultivation Base for State Key Lab of Refractories ＆ Ceramics Wuhan University of Science ＆ Technology Wuhan 430081 China department of Chemistry ＆ Materials Science Naval University of Engineering Wuhan 430033 China

The microstructured surface of materials were fabricated by a two-step acid-base catalyzed sol-gel process. In fluorinated polymer with PTFE doping, the well-proportioned composite sols were prepared using sol-gel processing under the hydrochloric acid and deficiency of water conditions. After the substrate was coated by composite sols, and the gelation treatment on the surface of composite coating, the micrometer-scale and nanometer-scale hierarchical structures were formed in surface layer of material. XPS and TEM technologies were employed to identify that the gelation occurs just on the surface of composite coating. The morphology of coating surface was observed by SEM and AFM technologies. The microstructured surface of material can be fabricated using this inexpensive and easily controlled method on low surface energy resin materials, the super-hydrophobic coatings materials can be prepared.

关键词： surface gelation technology roughness contact angle super-hydrophobic

1,2,5,6-Naphthalene Diimides:A Class of Promising Building Blocks for Organic Semiconductors

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Chinese Journal of Chemistry 2023年第10期41卷 1226-1234页

作者： Zheng zhao Congwu Ge Xueqian zhao Jintao Huang Xike Gao Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of SciencesShanghai 200032China

Organic semiconductors have drawn extensive atten-tion due to their optoelectronic properties and wide applications in organic *** comparison with the popular 1,4,5,8-naphthalene diimides(1,4,5,8-NDIs),the angular-shaped 1,2,5,6-NDIs have exhibited tunable photophysical properties,self-as-sembly behaviors and charge transporting *** to these unique features,1,2,5,6-NDIs show great potential for construction of high performance n-func-tional *** this review,we highlight the recent advances and future prospects of 1,2,5,6-NDI-basedπ-systems in the field of organic optoelectronics,in-cluding molecular design,synthesis,structure-prop-erty relationships as well as the applications in high performance organic field-effect transistors,organic photovoltaics,perovskite solar cells,and so on.

关键词： Organic semiconductors Electron acceptors design and synthesis 1,2,5,6-NDI Structural isomerism Polymer acceptors Organic electronics

Second-order cone AC optimal power flow: convex relaxations and feasible solutions

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Journal of Modern Power Systems and Clean Energy 2019年第2期7卷 268-280页

作者： zhao YUAN Mohammad Reza HESAMZAdeH department of Electric Power and Energy Systems KTH Royal Institute of Technology

Optimal power flow(OPF) is the fundamental mathematical model to optimize power system *** on conic relaxation, Taylor series expansion and McCormick envelope, we propose three convex OPF models to improve the performance of the second-order cone alternating current OPF(SOC-ACOPF) model. The underlying idea of the proposed SOC-ACOPF models is to drop assumptions of the original SOC-ACOPF model by convex relaxation and approximation methods.A heuristic algorithm to recover feasible ACOPF solution from the relaxed solution of the proposed SOC-ACOPF models is developed. The proposed SOC-ACOPF models are examined through IEEE case studies under various load scenarios and power network congestions. The quality of solutions from the proposed SOC-ACOPF models is evaluated using MATPOWER(local optimality) and LINDOGLOBAL(global optimality). We also compare numerically the proposed SOC-ACOPF models with other two convex ACOPF models in the *** numerical results show robust performance of the proposed SOCACOPF models and the feasible solution recovery algorithm.

关键词： Optimal power flow Conic relaxation McCormick envelope Taylor series expansion Feasible solution