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Polyelectrolytes of Inorganic Polyoxometalates:Prospecting New Charged Polymers for Advanced Applications

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Chinese Journal of Polymer Science 2024年第9期42卷 1254-1269,I0005页

作者： De-Yin wang Zhuo-qun Lu wei wang College of Medical Linyi UniversityLinyi276000China Center for Synthetic Soft Materials Key Laboratory of Functional Polymer Materials of the Ministry of EducationInstitute of Polymer ChemistryNankai UniversityTianjin300071China

Polyelectrolytes are charged polymers comprising macromolecules in which substantial portions of the constituent units contain cationic(e.g.,pyridinium,ammonium)or anionic(e.g.,sulfonate,carboxylate)groups,which possess special functions from the features of counterions,such as dissociation to charged species,mechanical stability,phase behavior,***,functional polyelectrolytes have been widely applied in many *** this perspective,we present some progresses in the studies of poly(polyoxometalate)s,denoted as poly(POM)s,as a kind of new charged polymers/polyelectrolytes,by covalent bonding between the inorganic polyoxometalate(POM)clusters and the organic polymer *** to the distinct positions of POMs in polymer chain and functions of poly(POM)s,they are divided into the following four categories:crosslinked poly(POM);side-chain poly(POM);backbone poly(POM),including poly(POM)-conjugated polymer hybrid and block poly(POM)-polymer;and POM-based covalent organic framework(PCOF).This perspective introduces the synthesis methods of poly(POM)polyelectrolytes and their macromolecular and aggregate structural characteristics,while also focusing on their properties and *** application areas include catalysis,thermal resistance,optical functions,fuel cells and batteries,etc.

关键词： Charged polymer Polyelectrolyte Polyoxometalate Poly(polyoxometalate) Covalent organic framework

A spillover network analysis of the global crude oil market:Evidence from the post-financial crisis era

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Petroleum Science 2021年第4期18卷 1256-1269页

作者： Zhi-Yi Ouyang Zheng Qin Hong Cao Tian-Yu Xie Xing-Yu Dai qun-wei wang College of Economics and Management Nanjing University of Aeronautics and Astronautics29 Jiangjun AvenueNanjing211106China Research Center for Soft Energy Science Nanjing University of Aeronautics and AstronauticsNanjing211106China

The frequent occurrence of geopolitical crises in the post-financial crisis era is driving the rethinking behind whether the global crude oil market is still a highly connected"great pool".Using the spillover network model suggested by Baruník and Krehlík(2018),and the daily data of 31 global crude oil markets from 2009 to 2019,this study examines the return and volatility spillover effects and their timevarying behavior in six crude oil market segments at different *** findings indicate that heterogeneity exists in the co-movements between global crude oil markets in the post-financial crisis *** the medium term,both return and volatility spillover effects are not significant,which makes the diversified portfolio strategy *** in the Europe and Central Asian regions take the lead in return *** contrast,Asia-Pacific regional prices contribute the most in terms of volatility ***-term volatility spillovers increase sharply when confronted with oil-related events in the postfinancial crisis ***,policymakers should take effective measures to prevent any large-scale risk transmission in the long run.

关键词： Oil price Network analysis Spillover effect Multiscale analysis Baruník and Krehlík model

Propagation form of internal cracks induced by continuous casting soft reduction and control strategy for internal quality

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Journal of Iron and Steel Research International 2024年第3期31卷 622-633页

作者： Pu wang Liang Chen qun-wei Tang wei-tao Li Shao-xiang Li Jia-quan Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China weifang Special Steel Group Co..Ltd. Weifang 262400ShandongChina School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China

The propagation form of internal cracks induced by continuous casting soft reduction and the control strategy for enhancing the internal quality of 45 steel through industrial trials and a three-dimensional flow-heat transfer-solidification coupling model were *** results showed that the internal cracks induced by soft reduction exhibited a characteristic of being"coarse in the middle and fine at both ends",and displayed an elliptical arc distribution on the loose side of the strand cross *** cracks originated within the brittle temperature range and propagated inward to the liquid impenetrable temperature and outward to the zero ductility temperature or *** control strategy for enhancing the internal quality of the 45 steel strand through soft reduction is to adjust the casting speed or the reduction zone appropriately,ensuring that the central solid fraction of the reduction zone falls within the range of *** this point,a reasonable reduction amount is allocated to eliminate the center shrinkage cavities and center segregation,even if it results in minor reduction-induced cracks.

关键词： Continuous casting Soft reduction Crack propagation Internal quality Control strategy

The Mixed-Mode Fatigue Crack Propagation Model of Piezoelectric Materials Under Electric Fatigue Loading by the Jk-Integral

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Acta Mechanica Solida Sinica 2024年第4期37卷 634-641页

作者： Xianghua Chen Chunguang wang qun Li The Institute of Xi’an Aerospace Solid Propulsion Technology Xi’an710025China State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an710049China

The electric fatigue load has a significant effect on the crack propagation behavior and failure life of piezoelectric materials and devices. In this paper, an electrical mixed-mode fatigue crack propagation model for piezoelectric materials is proposed based on the piezoelectric Jk-integral theory. The crack initiation, propagation, and life prediction criteria of piezoelectric materials under electric fatigue loading are given by this model, and the finite element simulation model is established to study the electrical mixed-mode crack propagation behavior of piezoelectric structures. Meanwhile, the electrical mixed-mode fatigue crack propagation model is applied to the fatigue crack propagation behavior of a piezoelectric typical defective structure, the crack–hole interference model. The mixed-mode crack propagation, fatigue life, and the interference behavior between the crack and hole at various hole locations of the crack–hole interference model are well recognized by this model. The crack propagation behavior under different electrical load intensities is also considered. The results show that the hole in front of the crack tip inhibits crack propagation to a certain extent, and the strength of electrical load affects the fatigue life of piezoelectric materials and structures. Therefore, the proposed electrical mixed-mode fatigue crack propagation model provides a reference for predicting the mixed-mode fatigue crack propagation behavior and fatigue life of piezoelectric structures under electric fatigue loading.

关键词： Configurational force J k-integral Piezoelectric Mixed-mode crack propagation Life prediction

Recent Advances of Bioactive Marine Natural Products in Drug Discovery

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Journal of Ocean University of China 2024年第5期23卷 1297-1318页

作者： ZHANG qun LV Liuxia wang Wenhui wei Meiyan GU Yucheng SHAO Changlun Key Laboratory of Marine Drugs Ministry of Education of ChinaSchool of Medicine and PharmacyOcean University of ChinaQingdao 266100China Laboratory for Marine Drugs and Bioproducts Qingdao Marine Science and Technology CenterQingdao 266237China Key Laboratory of Tropical Medicinal Resource Chemistry of Ministry of Education College of Chemistry and Chemical EngineeringHainan Normal UniversityHaikou 571158China Syngenta Jealott’s Hill International Research Centre BracknellBerkshire RG426EYUK

Marine natural products(MNPs)are valuable resources for drug *** date,17 drugs from marine sources are in clinical use,and 33 pharmaceutical compounds are in clinical *** the success of drug development from the marine resources is higher than the industry *** is a feasible strategy to conduct the discovery of druglead compounds based on marine chemical ecology by fully exploiting the pharmacological potential of marine chemical defense *** the search for bioactive MNPs,our group has constructed a biological resources library including more than 1500 strains of *** on the strategy of Blue Drug Library,we have discovered a series of novel MNPs with abundant biological *** efficient and scalable total synthesis of(+)-aniduquinolone A(44)and pesimquinolone I(48)have been completed,which will facilitate access to sufficient quantities of candidates for in vivo pharmacological and toxicological *** a nucleoprotein(NP)inhibitor,QLA(75)possesses significant anti-influenza A virus(IAV)activities both in vitro and in ***-00803(76)is a potent and selective AMP-activated kinase(AMPK)activator that can effectively inhibit metabolic disorders and metabolic dysfunction-associated steatohepatitis(MASH)***,we identified two new candidate molecules with potent anti-hepatocellular carcinoma ***,as a natural guanine-nucleotide exchange factors for ADP-ribosylation factor GTPases(Arf-GEFs)inhibitor prodrug,CHNQD-01255(78)is qualified to be developed as a targeted candidate anticancer drug,which may be promising to apply for cancer ***,it is evident that MNPs play an important role in drug development.

关键词： marine medicinal organisms natural products marine drug discovery and optimization drug development

Mechanical responses of anchoring structure under triaxial cyclic loading

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第2期16卷 545-560页

作者： Peng wang Nong Zhang qun wei Xingliang Xu Guangzhen Cui Aoran Li Sen Yang Jiaguang Kan State Key Laboratory of Coal Resources and Safe Mining School of MinesChina University of Mining and TechnologyXuzhou221116China School of Civil Engineering Xuzhou University of TechnologyXuzhou221116China School of Mechanical Engineering Jiangsu University of TechnologyChangzhou213001China

Dynamic load on anchoring structures(AS)within deep roadways can result in cumulative damage and *** study develops an experimental device designed to test AS under triaxial *** device enables the investigation of the mechanical response,failure mode,instability assessment criteria,and anchorage effect of AS subjected to combined cyclic dynamic-static triaxial stress *** results show that the peak bearing strength is positively correlated with the anchoring matrix strength,anchorage length,and edgewise compressive *** bearing capacity decreases significantly when the anchorage direction is severely *** free face failure modes are typically transverse cracking,concave fracturing,V-shaped slipping and detachment,and spallation ***,when the anchoring matrix strength and the anchorage length decrease while the edgewise compressive strength,loading rate,and anchorage inclination angle increase,the failure intensity *** is determined by a negative tangent modulus of the displacement-strength curve or the continued deformation increase against the general downward *** cyclic loads,the driving force that breaks the rock mass along the normal vector and the rigidity of the AS are the two factors that determine roadway ***,a control measure for surrounding rock stability is proposed to reduce the internal driving force via a pressure relief method and improve the rigidity of the AS by full-length anchorage and grouting modification.

关键词： Triaxial stress Dynamic-static combination load Cyclic loading Anchoring structure(AS) Cumulative damage

Low-Temperature Reforming Products Coupling Spark Plug on Gasoline Compression Ignition and Combustion Characteristics under Low-Load Condition

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Journal of Thermal Science 2024年第6期33卷 2386-2398页

作者： LIU Long LI Mingkun CAO qun wang Yang wang Xichang College of Power and Energy Engineering Harbin Engineering University China Helicopter Research and Development Institute

Gasoline compression combustion engine has the advantages of low emission and high efficiency,which is very promising for research,but it is difficult to apply under low-load *** has the characteristics of low reactivity;in the case of low thermodynamic state in the cylinder,the fire delay period of the fuel is longer,and the combustion phase is relatively lagging,which will lead to the increase of combustion cycle fluctuations,and even difficult to ignite and other adverse combustion *** order to improve the combustion stability of Gasoline Compression Ignition（GCI） engine under low-load condition and expand the limit of low-load combustion boundary,gasoline was reformed without catalyst under the boundary condition of reforming temperature of 488 K and reforming equivalent ratio of 8,and the concentration of reformed product was measured by a gas detection ***,the coupling of the reformed product and spark plug with GCI engine under low-load condition was investigated to analyze the effect on engine combustion and *** results showed that the initial combustion timing of the low-load GCI engine was late,but the addition of reformed products could advance the combustion phase,shorten the combustion duration,reduce single-cycle NOxemission,and improve the small-load operation characteristics of GCI *** spark plug ignition on the basis of adding reformed products could further improve the problem of combustion stability under low-load GCI *** the optimization effect became more obvious as the ignition position of the spark plug moves ***,spark plug ignition would cause local high temperature areas,resulting in an increase in NOxemission.

关键词： combustion emission gasoline low-temperature reform spark plug

CO2-Induced Modulation of Si-O Bonds for Low Temperature Plastic Deformation of Amorphous Silica Nanoparticles with Enhanced Photoluminescence

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Energy & Environmental Materials 2024年第4期7卷 404-412页

作者： Kang Huang Wenzhuo Wu Song Xu Pengfei Yan Zhongming wei qun Xu Henan Institute of Advanced Technology Zhengzhou University College of Materials Science and Engineering Zhengzhou University State Key Laboratory of Superlattices and Microstructures Institute of Semiconductors Chinese Academy of Sciences

Modulation of Si-O bonds under mild conditions has been a challenging issue in the field of material science,which is critical to manufacture highperformance silica-based optical and photonic ***,we introduce a nondestructive technique to achieve Si-O bond rearrangement,leading to plastic deformation and photoluminescence enhancement of amorphous silica nanoparticles using supercritical carbon dioxides in EtOH/H2O solution under mild temperature.

关键词： amorphous silica anisotropic stress photoluminescence plastic deformation supercritical CO2

Torque Limit-based Inertial Control Method Based on Delayed Support for Primary Frequency Control of Wind Turbines

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 561-570页

作者： wei Gu Zaiyu Chen qun Li Minghui Yin Qiang Li Yun Zou School of Automation Nanjing University of Science and TechnologyNanjing 210094China State Grid Jiangsu Electric Power Co. Ltd.Research InstituteNanjing 211103China

To avoid the secondary frequency dip caused by the steep drop of the electrical power of wind turbines(WTs)at the end of frequency support stage,the torque limit-based iner-tial control(TLIC)method sets the power reference as a linear function of rotor speed,rather than the step form for the step-wise inertial ***,the compensation effect on the frequency nadir(FN)caused by the load surge is weakened as the TLIC power is no longer in the step ***,the maximum point of the frequency response component(FRC)contributed by TLIC occurs earlier than the minimum point of FRC corresponding to the load surge,so that the FN cannot be adequately ***,this paper first investigates the relation between the peak and nadir times of FRCs stimulated by the TLIC and load *** this basis,with the compensation principle of matching the peak and nadir times of FRCs,the improved TLIC method based on delayed support is ***,the effectiveness of the proposed method is validated via the experiments on the test bench of wind-integrated power system.

关键词： Wind turbine frequency response component torque limit inertial control delayed support