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Toughening Mechanism of Nanocomposite Physical Hydrogels Fabricated by a Single Gel Network with Dual Crosslinking-- The Roles of the Dual Crosslinking Points

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Chinese Journal of Polymer Science 2017年第1期35卷 25-35页

作者： fu-kuan shi ming zhong li-qin zhang xiao-ying liu 谢续明 Key Laboratory of Advanced Materials (MOE) Department of Chemical Engineering Tsinghua University Beijing 100084 China

A facile method to fabricate tough and highly stretchable polyacrylamide （PAM） nanocomposite physical hydrogel （NCP gel） was proposed. The hydrogels are dually crosslinked single network with the PAM grafted vinyl hybrid silica nanoparticles （VSNPs） as the analogous covalent crosslinking points and the reversible hydrogen bonds among the PAM chains as the physical crosslinking points. In order to further elucidate the toughening mechanism of the PAM NCP gel, especially to understand the role of the dual crosslinking points, the PAM hybrid hydrogels （H gels） and a series of poly（acrylamide-co-dimethylacrylamide）（P（AM-co-DMAA）） NCP gels were designed and fabricated. Their mechanical properties were compared with those of the PAM NCP gels. The PAM H gels are prepared by simply mixing the PAM chains with bare silica nanoparticles （SNPs）. Relative to the poor mechanical properties of the PAM H gel, the PAM NCP gel is remarkably tough and stretchable and also generates large number of micro-cracks to stop notch propagation, indicating the important role of PAM grafted VSNPs in toughening the NCP gel. In the P（AM-co-DMAA） NCP gels, the P（AM-co- DMAA） chains are grafted on VSNPs and the polydimethylacrylamide （PDMAA） only forms very weak hydrogen bonds between themselves. It is found that mechanical properties of the PAM NCP gel, such as the tensile strength and the elongation at break, are enhanced significantly, but those of the P（AM-co-DMAA） NCP gels decreased rapidly with decreasing AM content. This result reveals the role of the hydrogen bonds among the grafted polymer chains as the physical crosslinking points in toughening the NCP gel.

关键词： Dual crosslinking single network Nanocomposite physical hydrogel Toughening mechanism

Transparent h-BN/polyacrylamide nanocomposite hydrogels with enhanced mechanical properties

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Chinese Chemical Letters 2016年第9期27卷 1490-1494页

作者： Zhi-Qiang Duan Ming Zhong fu-kuan shi Xu-Ming Xie Laboratory of Advanced Materials (MOE) Department of Chemical Engineering Tsinghua University

In this study, a facile way has been proposed to prepare transparent, tough and flexible polyacrylamide （PAM） hydrogels which is composed of a dually crosslinked single network by chemical crosslinking of N,N＇-methylenebisacrylamide （BIS） and physical crosslinking of hydrophilic hexagonal boron nitride （h- BN） nanosheets. The resulting h-BN/PAM nanocomposite hydrogels are highly transparent, and exhibit significantly enhanced mechanical properties compared to the dark （GO）/PAM nanocomposite hydrogels or chemical crosslinking PAM hydrogels. Thus it opens up new opportunities for developing next- generation transparent, tough and flexible hydrogels that hold great promise in such important applications as light responsive soft robot and liquid microlenses.

关键词： Hexagonal boron nitride Polyacrylamide Nanocomposite hydrogels Mechanical properties Transparency

Phase Transition Temperature Controllable Poly(acrylamide-co-acrylic acid) Nanocomposite Physical Hydrogels with High Strength

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Chinese Journal of Polymer Science 2016年第10期34卷 1261-1269页

作者： li-qin zhang li-wen chen ming zhong fu-kuan shi xiao-ying liu 谢续明 Laboratory of Advanced Materials (MOE) Department of Chemical Engineering Tsinghua University Beijing 100084 China

Poly（acrylamide-co-acrylic acid） nanocomposite physical （P（AAm-co-AAc）NCP） hydrogels have been prepared through the in situ free radical solution polymerization based on a ＂single network, dual cross-linkings＂ strategy. The P（AAm-co-AAc） NCP hydrogels are composed of nanobrushes of P（AAm-co-AAc） chains grafted on the surface of vinyl- hybrid silica nanoparticles （VSNPs）. In the hydrogel system, the VSNPs act as the ＂analogous chemical cross-linking points＂ once the hydrogen bonds formed between the P（AAm-co-AAc） chains of the nanobrushes, thus leading to the fabrication of high-strength P（AAm-co-AAc） NCP hydrogels. Compared with conventional thermosensitive P（AAm-co-AAc） hydrogels, the P（AAm-co-AAc） NCP hydrogels have a broader range of phase transition temperature, which can be adjusted by altering the monomer ratio, the VSNPs concentration, the addition of urea and N,N-dimethylacrylamide （DMAAm）. At the same time, the mechanical properties of the P（AAm-co-AAc） NCP hydrogels have been improved significantly by the introduction of VSNPs. furthermore, both the phase transition and the tensile strength of the P（AAm-co-AAc） NCP hydrogels are largely influenced when Fe3＋ ions are introduced as the ionic crosslinkers into the hydrogel networks.

关键词： Poly(acrylamide-co-acrylic acid) Nanocomposite physical hydrogels Phase transition High strength.

Tough superabsorbent poly(acrylic acid) nanocomposite physical hydrogels fabricated by a dually cross-linked single network strategy

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Chinese Chemical Letters 2016年第3期27卷 312-316页

作者： Ming Zhong fu-kuan shi Yi-Tao Liu Xiao-Ying Liu Xu-Ming Xie Laboratory of Advanced Materials (MOE) Department of Chemical EngineeringTsinghua University

In this work, we report a facile method for the preparation of tough and highly stretchable physical hydrogels by dual cross-linking composed of vinyl-hybrid silica nanoparticles（VSNPs） as multivalent covalent cross-linking and hydrogen bonding as physical cross-linking. Poly（acrylic acid） nanocomposite physical hydrogels（NCP gels） are obtained without adding any organic chemical cross-linkers. When the content of VSNPs is 0.7 wt%（relative to the monomer）, the NCP gels exhibit good mechanical properties（fracture strength = 370 k Pa, elongation at break = 2200%） and a high swelling capacity in both deionized water（2300 g/g） and saline（220 g/g）. Meanwhile, the NCP gels have good recovery ability.

关键词： Nanocomposite physical hydrogels Vinyl hybrid silica nanoparticles Swelling capacity Fracture strength Stretchability Recovery ability

Quantum public-key crypto via EPR pairs

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 58-63页

作者： Xiang-Qun fu Hong-Wei Li Jian-Hong shi Tan Li Wan-Su Bao Henan Key Laboratory of Quantum Information and Cryptography Information Engineering University Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of China

With the development of quantum computing technology, quantum public-key cryptography is gradually becoming an alternative to the existing classical public-key cryptography. This paper designs a quantum trapdoor one-way function via EPR pairs and quantum measurements. Based on this, a new quantum public-key cryptosystem is presented, which offers forward security,and can resist the chosen-plaintext attack and chosen-ciphertext attack. Compared with the existing quantum public-key cryptos,eavesdropping can be automatically detected in this new quantum public-key cryptosystem under a necessary condition, which is also detailed in the paper.

关键词： quantum public-key crypto trapdoor one-way function EPR pairs

Bidirectional regulation of the brain-gut-microbiota axis following traumatic brain injury

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Neural Regeneration Research 2025年第8期20卷 2153-2168页

作者： Xinyu You Lin Niu Jiafeng fu shining Ge Jiangwei shi Yanjun Zhang Pengwei Zhuang National Key Laboratory of Chinese Medicine Modernization Tianjin University of Traditional Chinese MedicineTianjinChina Haihe Laboratory of Modern Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjinChina First Teaching Hospital of Tianjin University of Traditional Chinese Medicine TianjinChina National Clinical Research Center for Chinese Medicine Acupuncture and Moxibustion TianjinChina

Traumatic brain injury is a prevalent disorder of the central nervous *** addition to primary brain parenchymal damage,the enduring biological consequences of traumatic brain injury pose long-term risks for patients with traumatic brain injury;however,the underlying pathogenesis remains unclear,and effective intervention methods are *** dysfunction is a significant consequence of traumatic brain *** the most densely innervated peripheral tissue in the body,the gut possesses multiple pathways for the establishment of a bidirectional“brain-gut axis”with the central nervous *** gut harbors a vast microbial community,and alterations of the gut niche contribute to the progression of traumatic brain injury and its unfavorable prognosis through neuronal,hormonal,and immune pathways.A comprehensive understanding of microbiota-mediated peripheral neuroimmunomodulation mechanisms is needed to enhance treatment strategies for traumatic brain injury and its associated *** comprehensively reviewed alterations in the gut microecological environment following traumatic brain injury,with a specific focus on the complex biological processes of peripheral nerves,immunity,and microbes triggered by traumatic brain injury,encompassing autonomic dysfunction,neuroendocrine disturbances,peripheral immunosuppression,increased intestinal barrier permeability,compromised responses of sensory nerves to microorganisms,and potential effector nuclei in the central nervous system influenced by gut ***,we reviewed the mechanisms underlying secondary biological injury and the dynamic pathological responses that occur following injury to enhance our current understanding of how peripheral pathways impact the outcome of patients with traumatic brain *** review aimed to propose a conceptual model for future risk assessment of central nervous system-related diseases while elucidating novel insights into the bidirectional effec

关键词： traumatic brain injury brain-gut-microbiome axis gut microbiota neuroimmune immunosuppression host defense vagal afferents bacterial infection dorsal root ganglia nociception neural circuitry

The interaction between KIF21A and KANK1 regulates dendritic morphology and synapse plasticity in neurons

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Neural Regeneration Research 2025年第1期20卷 209-223页

作者： shi-Yan Sun Lingyun Nie Jing Zhang Xue Fang Hongmei Luo Chuanhai fu Zhiyi Wei Ai-Hui Tang Hefei National Research Center for Physical Sciences at the Microscale CAS Key Laboratory of Brain Function and DiseaseMinistry of Education Key Laboratory for Membrane-less Organelles and Cellular DynamicsDivision of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina Institute of Artificial Intelligence Hefei Comprehensive National Science CenterHefeiAnhui ProvinceChina CAS Center for Excellence in Molecular Cell Sciences Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui ProvinceChina Department of Neurobiology School of Life SciencesSouthern University of Science and TechnologyShenzhenGuangdong ProvinceChina Brain Research Center Southern University of Science and TechnologyShenzhenGuangdong ProvinceChina

Morphological alterations in dendritic spines have been linked to changes in functional communication between neurons that affect learning and ***-4 KIF21A helps organize the microtubule-actin network at the cell cortex by interacting with KANK1;however,whether KIF21A modulates dendritic structure and function in neurons remains *** this study,we found that KIF21A was distributed in a subset of dendritic spines,and that these KIF21A-positive spines were larger and more structurally plastic than KIF21A-negative ***,the interaction between KIF21A and KANK1 was found to be critical for dendritic spine morphogenesis and synaptic *** of either KIF21A or KANK1 inhibited dendritic spine morphogenesis and dendritic branching,and these deficits were fully rescued by coexpressing full-length KIF21A or KANK1,but not by proteins with mutations disrupting direct binding between KIF21A and KANK1 or binding between KANK1 and *** down KIF21A in the hippocampus of rats inhibited the amplitudes of long-term potentiation induced by high-frequency stimulation and negatively impacted the animals’cognitive *** together,our findings demonstrate the function of KIF21A in modulating spine morphology and provide insight into its role in synaptic function.

关键词： actin cytoskeleton dendrite KANK1 KIF21A microtubule spine morphology spine synaptic plasticity talin1

Amperometric Glucose Sensor Based on Batch CuO-Modified Screen-Printed Silver-Carbon Electrodes

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期40卷 35-41页

作者： XIA Haiyan HUANG Yin YANG Hua WANG Xintian shi Jianping LIU Lixia fu Yacheng QUAN Changyun LI Suyuan Cofoe Medical Technology Company Limited Changsha 410000China Institute of New Energy Hexi UniversityZhangye 734000China Chemistry and Chemical Engineering Central South UniversityChangsha 410000China

CuO nanoparticles were successfully synthesized via a two-jet electrospun method,and then screen-printed on silver-carbon electrodes,forming CuO-modified Ag-C(CuO/Ag-C)disposable strip *** natural environment condition for glucose detection,the obtained CuO/Ag-C electrodes show a high sensitivity of 540 nA·mM^(-1)·cm^(-2),and a low limit of detection(0.68 mM)in a wide linear response range of 0.68 mM and 3 mM(signal/noise=3),*** addition,the CuO/Ag-C electrodes also exhibit excellent anti-interference,air stability and *** a result,the fabrication of CuO nanoparticles via an electrospun process and the technique of screen-printed electrodes are of great significance for glucose detection.

关键词： electrochemical sensor CuO nanoparticles glucose detection screen-printing technique

利用聚乙烯醇结晶辅助制备多重交联的高强度聚丙烯酰胺水凝胶

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高分子学报 2017年第3期27卷 491-497页

作者：时富宽钟鸣张丽琴刘晓颖谢续明清华大学化工系先进材料教育部重点实验室北京100084

在表面带有C=C双键的乙烯基杂化二氧化硅纳米颗粒(vinyl hybrid silica nanoparticle,VSNP)上接枝丙烯酰胺(AM),所得到的纳米刷状凝胶因子通过聚丙烯酰胺(PAM)间的氢键形成物理交联点,则多官能化的VSNP可作为拟共价交联点构筑双重交联... 详细信息

在表面带有C=C双键的乙烯基杂化二氧化硅纳米颗粒(vinyl hybrid silica nanoparticle,VSNP)上接枝丙烯酰胺(AM),所得到的纳米刷状凝胶因子通过聚丙烯酰胺(PAM)间的氢键形成物理交联点,则多官能化的VSNP可作为拟共价交联点构筑双重交联的单一网络纳米复合物理水凝胶(nanocomposite physical hydrogel,NCP gel),表现出较高的强度和超拉伸性.为了进一步提高凝胶的强度和韧性,将少量PVA和PAM/VSNP纳米刷混合制成凝胶,通过冷冻-融化处理,使与PAM分子链相互缠绕并形成氢键作用的PVA结晶,形成新的交联点进一步交联PAM NCP gel,得到多交联的PAM NCP gel体系.通过拉曼光谱和示差扫描量热分析,证明凝胶中的PVA通过氢键既可以与PAM相互作用,又形成微晶为新交联点,大大增强了NCP gel的力学性能,与PAM NCP gel相比,凝胶的拉伸强度和断裂能分别从313 k Pa和1.41×104 J/m^2提高到了557k Pa和4.65×104 J/m^2.

关键词：聚乙烯醇微晶多重交联高强度聚丙烯酰胺水凝胶