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Chinese Journal of Polymer Science 2024年第5期42卷 591-603,I0006页

作者： Qiong-Jun Xu Zhao-Yang Yuan Chang-Cheng Wang Hao Liang Yu Shi Hai-Tao Wu Hu Xu Jing Zheng Jin-Rong Wu State Key Laboratory of Polymer Materials Engineering College of Polymer Science and EngineeringSichuan UniversityChengdu610065China

Semi-interpenetrating(semi-IPN)hydrogels formed by the continuous interpenetration of cross-linked polymer network and linear non-crosslinked polymer with multifunctionality are widely used in biomedical and other ***,the negative impact of linear polymer on the homogeneity of the cross-linked network often leads to a decrease in the mechanical properties of semi-IPN hydrogels and severely limits their ***,a bioinspired hydrogen-bonding induced phase separation strategy is presented to construct the tough semi-IPN polyvinylpyrrolidone/polyacrylamide hydrogels(named PVP/PAM hydrogels),including the linear polymer polyvinylpyrrolidone(PVP)and cross-linked polyacrylamide(PAM)*** resultant PVPx/PAM hydrogels exhibit unique phase separation induced by the hydrogen bonding between PVP and PAM and affected by the amount of substance of ***,the phase separation of PVPx/PAM hydrogels results in excellent mechanical properties with a strain of 2590%,tensile strength of 0.28 MPa and toughness of 2.17 MJ/m^(3).More importantly,the hydrogen bonding between PVP and PAM firstly disrupts to dissipate energy under external forces,so the PVPx/PAM hydrogels exhibit good self-recovery properties and outperform chemically cross-linked PAM hydrogels in impact resistance and damping *** is believed that the PVPx/PAM hydrogels with hydrogen-bonding induced phase separation possess more potential application prospects.

关键词： tough Semi-interpenetrating networks Polyvinylpyrrolidone/polyacrylamide Hydrogels Phase separation

tough,conductive hydrogels with double-network based on hydrophilic polymer assistant well-dispersed carbon nanotube for innovative force sensor

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Science China(Technological Sciences) 2022年第5期65卷 1160-1168页

作者： CHEN GuoYin GUO Ying HSIAO S.Benjamin HOU Kai ZHU MeiFang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and EngineeringDonghua UniversityShanghai201620China Department of Chemistry Stony Brook UniversityNew York11794USA

In recent years,conductive hydrogels have become a promising candidate for application in fields such as tissue engineering and flexible electronic devices because of their conductivity,soft and wet ***,the preparation of tough and uniformly conductive hydrogels remains challenging because conductive nanofillers tend to aggregate during hydrogel ***,a hydrophilic polymer assistant dispersion strategy is proposed to fabricate a tough,conductive composite hydrogel with doublenetwork based on well-dispersed carbon nanotubes(CNTs).In particular,A@T_(2.0)/polyacrylamide(PAM)hydrogels showed a tensile strength of 332.9 kPa,elongation of 584.6%,Young’s modulus of 91.5 kPa,and conductivity of 2.765 S m^(-1),and a demonstration was performed to show the strain sensing for health monitoring and *** showed that the fabricated conductive hydrogels offer promising and broad insights in the field of wearable sensors for health monitoring,innovative electronics,and human-machine interactions.

关键词： alginate carbon nanotubes conductive hydrogel tough force sensing

Designing mechanically tough graphene oxide materials using deep reinforcement learning

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npj Computational Materials 2022年第1期8卷 2139-2147页

作者： Bowen Zheng Zeyu Zheng Grace X.Gu Department of Mechanical Engineering University of CaliforniaBerkeleyCA94720USA Department of Industrial Engineering and Operations Research University of CaliforniaBerkeleyCA94720USA

Graphene oxide(GO)is playing an increasing role in many ***,it remains unanswered how to strategically distribute the functional groups to further enhance *** utilize deep reinforcement learning(RL)to design mechanically tough *** design task is formulated as a sequential decision process,and policy-gradient RL models are employed to maximize the toughness of *** show that our approach can stably generate functional group distributions with a toughness value over two standard deviations above the mean of random *** addition,our RL approach reaches optimized functional group distributions within only 5000 rollouts,while the simplest design task has 2×10^(11)***,we show that our approach is scalable in terms of the functional group density and the GO *** present research showcases the impact of functional group distribution on GO properties,and illustrates the effectiveness and data efficiency of the deep RL approach.

关键词： toughness tough oxide

Super-anti-freezing,tough and adhesive titanium carbide and L-ornithine-enhanced hydrogels

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生物质资源与工程(英文) 2023年第2期8卷 136-145页

作者： Zhangkang Li Jamie LeBlanc Hitendra Kumar Hongguang Zhang Weijun Yang Xiao He Qingye Lu Jeffrey Van Humbeck Keekyoung Kim Jinguang Hu Department of Biomedical Engineering University of CalgaryCalgaryUniversity Drive NWCalgaryAB T2N 1N4Canada Department of Chemistry University of CalgaryUniversity Drive NWCalgary T2N 1N4AlbertaCanada Department of Mechanical and Manufacturing Engineering University of CalgaryUniversity Drive NWCalgary T2N 1N4AlbertaCanada Pathology and Laboratory Medicine Cumming School of EngineeringUniversity of CalgaryHospital Drive NWT2N 4N1AlbertaCanada Department of Chemical and Petroleum Engineering University of CalgaryUniversity Drive NWCalgary T2N 1N4AlbertaCanada Key Laboratory of Synthetic and Biological Colloids Ministry of EducationSchool of Chemical and Material EngineeringJiangnan UniversityWuxiJiangsu214122China

Hydrogels are highly porous three-dimensional crosslinked polymer networks consisting of hy-drophilic polymers,employed most practically in medicine and industry,often as *** hydrogels suffer limitations in their mechanical properties,such as tensile and com-pression,and freeze at sub-zero temperatures,which compromise their ability as useful *** this study,the incorporation of L-ornithine-based zwitterionic monomer(OZM),titanium carbide(MXene),and glycerol within polyacrylamide hydrogels was used to prepare a novel polyacrylamide/polyL-ornithine-based zwitterion/MXene(PAM/Porn/MXene)hydrogel to im-prove the mechanical,adhesion,and anti-freezing properties of pure polyacrylamide *** study also analyzed the mechanical strength(tensile and compression),adhesion,and anti-freezing properties of a novel PAM/Porn/MXene hydrogel at 1%,4%,and 10%MXene concen-trations to establish to what extent the conductive MXene material enhanced these properties and concluded that the tensile and compressive properties improved linearly with the increase in the concentrations of MXene,adhesion decreased with the increased MXene concentrations,and syn-ergistic interaction between MXene and OZM significantly improved the anti-freezing properties up to-80°C.

关键词： Super-anti-freezing tough Adhesive L-ornithine MXene

Being tough: The secret weapon of plants against vascular pathogens

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Molecular Plant 2022年第6期15卷 934-936页

作者： Dandan Zhang Bin Lv Jin-Long Qiu State Key Laboratory of Plant Genomics Institute of MicrobiologyChinese Academy of SciencesBeijingChina CAS Center for Excellence in Biotic Interactions University of Chinese Academy of SciencesBeijingChina

Vascular plants are characterized by the existence of phloem and xylem vascular tissues that are specialized for water and nutrient transporting and mechanical *** xylem is composed of vessels and tracheids formed by non-living cells whose cellulose cell walls are stiffened with *** xylem tissues across different parts of the plant are interconnected to form a continuous water-conducting *** plants possess true stems,leaves,and roots,enabling them to expand to diverse habitats and to become the dominant type of land ***,to adapt to new habitats,vascular plants,being sessile,have to face some extreme environmental *** are a common and constant threat confronting plants as they migrate to new *** survive,plants have developed complex immune systems during an evolutionary arms race against pathogens.

关键词： habitat tough walls

tough Double Metal-ion Cross-linked Elastomers with Temperature-adaptable Self-healing and Luminescence Properties

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Chinese Journal of Polymer Science 2021年第5期39卷 554-565,I0005页

作者： Qi-Yan Yin Cheng-Hao Dai Huan Chen Kai Gou Hong-Zhou Guan Peng-Han Wang Jing-Tao Jiang Geng-Sheng Weng School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China Ningbo Key Laboratory of Specialty Polymers State Key Laboratory Base of Novel Functional Materials and Preparation ScienceNingbo UniversityNingbo 315211China

Smart materials with a combination of tough solid-like properties,fast self-healing and optical responsiveness are of interests for the development of new soft machines and wearable *** this work,tough physically cross-linked elastomers that show high mechanical strength,intriguing temperature-adaptable self-healing and fluorochromic response properties are designed using aluminum(Al)and fluorescent europium(Eu)ions as *** ionic Al-COOH binding is incorporated to construct the strong polymer network which mainly contributes to the mechanical robustness of the elastomer consisting of two interpenetrated *** Eu-iminodiacetate(IDA)coordination is mainly used to build the weaker but more dynamic network which dominate the elasticity,self-healing and luminescence of the *** Eu^(3+) and Al^(3+) contents give these supramolecular elastomers high *** temperature-sensitive Eu-IDA coordination enables tunable self-healing rate and efficiency along with fast Eu-centered"ON/OFF"switchable red *** mechanical,self-healing and luminescence properties of these elastomers can be adjusted by tuning the ratio of the two types of metal *** elastomer is potentially applicable for biosensors,wearable optoelectronics and anticounterfeiting materials.

关键词： Elastomer tough Self-healing Luminescence Temperature-sensitive

Simulating hydraulic fracturing processes in laboratory-scale geological media using three-dimensional tough-RBSN

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第6期10卷 1102-1111页

作者： Daisuke Asahina Pengzhi Pan Kimikazu Tsusaka Mikio Takeda John E.Bolander Geological Survey of Japan IbarakiJapan State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China INPEX Corporation TokyoJapan University of California DavisUSA

In this context, recent developments in the coupled three-dimensional(3 D) hydro-mechanical(HM)simulation tool tough-RBSN are presented. This tool is used to model hydraulic fracture in geological media, as observed in laboratory-scale tests. The tough-RBSN simulator is based on the effective linking of two numerical methods: tough2, a finite volume method for simulating mass transport within a permeable medium; and a lattice model based on the rigid-body-spring network(RBSN) concept. The method relies on a Voronoi-based discretization technique that can represent fracture development within a permeable rock matrix. The simulator provides two-way coupling of HM processes, including fluid pressure-induced fracture and fracture-assisted flow. We first present the basic capabilities of the modeling approach using two example applications, i.e. permeability evolution under compression deformation, and analyses of a static fracturing simulation. Thereafter, the model is used to simulate laboratory tests of hydraulic fracturing in granite. In most respects, the simulation results meet expectations with respect to permeability evolution and fracturing patterns. It can be seen that the evolution of injection pressure associated with the simulated fracture developments is strongly affected by fluid viscosity.

关键词： Hydraulic fracture Crack opening tough Rigid-body-spring network(RBSN) Permeability Injection pressure Fluid viscosity Hydro-mechanical(HM) processes

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tough LOVE

The World of Chinese 2021年第5期 88-90页

作者：杨婷婷不详

Everyone needs a break *** students,the vacation is a well-earned rest from all-nighters,exams,and dull lectures,as well as a time to catch up with family and friends back *** having to take care of their kids all sum... 详细信息

关键词： earned tough return

Winning the tough Battle of Forestalling and Defusing Financial Risks

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China Economic Transition 2018年第4期1卷 1-11页

作者： HE Dexu National Academy of Economic Strategy Chinese Academy of Social Sciences

At present,at the crossroads between building a moderately prosperous society in all respects and entering a critical moment as socialism with Chinese characteristics has entered a new *** is undergoing profound and complex changes and accordingly,the Communist Party of China(CPC)Central Committee has stressed on winning the tough battle of forestalling and defusing major risks,especially preventing and controlling financial *** is a major strategic plan laid out by the CPC Central Committee to combat the salient weaknesses constraining the progressive development of China’s *** an analysis of the economic situations in China and abroad,China is confident,determined,and capable of winning the tough battle of forestalling and defusing financial risks.

关键词： tough Forest winning

When the going gets tough...With the power of innovation, Swiss Textile Machinery members drive success in the yarn manufacturing sector

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China Textile 2019年第12期 54-55页

Yarn producers know that when the going gets tough–as it frequently does–they can depend on the proven quality of machines,key components and services from *** both high-volume segments and niches,Swiss Textile Machinery members have the innovative strength and the market focus to drive business success for spinners and synthetic fibre producers *** article introduces some of the latest solutions for competitive progress in this wide-ranging segment.

关键词： tough fibre competitive