检索结果-南通市图书馆

A molecular dynamics investigation of the deformation mechanism and shape memory effect of epoxy shape memory polymers

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2016年第3期59卷 89-95页

作者： hua Yang Zheng Dao Wang Ya Fang Guo xing hua shi Institute of Engineering Mechanics Beijing Jiaotong University State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences

Following deformation, thermally induced shape memory polymers(SMPs) have the ability to recover their original shape with a change in temperature. In this work, the thermomechanical properties and shape memory behaviors of three types of epoxy SMPs with varying curing agent contents were investigated using a molecular dynamics(MD) method. The mechanical properties under uniaxial tension at different temperatures were obtained, and the simulation results compared reasonably with experimental data. In addition, in a thermomechanical cycle, ideal shape memory effects for the three types of SMPs were revealed through the shape frozen and shape recovery responses at low and high temperatures, respectively, indicating that the recovery time is strongly influenced by the ratio of E-51 to 4,4'-Methylenedianiline.

关键词： shape memory polymer molecular dynamics simulation thermomechanics

Tunable band structures of polycrystalline graphene by external and mismatch strains

在线全文

学校读者我要写书评

暂无评论

Acta Mechanica Sinica 2012年第6期28卷 1539-1544页

作者： Jiang-Tao Wu xing-hua shi Yu-Jie Wei LNM Institute of Mechanics Chinese Academy of Sciences

Lacking a band gap largely limits the application of graphene in electronic devices. Previous study shows that grain boundaries （GBs） in polycrystalline graphene can dra- matically alter the electrical properties of graphene. Here, we investigate the band structure of polycrystalline graphene tuned by externally imposed strains and intrinsic mismatch strains at the GB by density functional theory （DFT） calcu- lations. We found that graphene with symmetrical GBs typ- ically has zero band gap even with large uniaxial and biax- ial strain. However, some particular asymmetrical GBs can open a band gap in graphene and their band structures can be substantially tuned by external strains. A maximum band gap about 0.19 eV was observed in matched-armchair GB （5, 5） I （3, 7） with a misorientation of θ = 13° when the applied uniaxial strain increases to 9%. Although mismatch strain is inevitable in asymmetrical GBs, it has a small influence on the band gap of polycrystalline graphene.

关键词： Graphene Grain boundary Defects Strain and gap

Probing mechanical principles of cell-graphene-family nanomaterials(GFNs) interaction

在线全文

学校读者我要写书评

暂无评论

Probing mechanical principles of cell-graphene-family nanoma...

Probing mechanical principles of cell

第十届全国生物力学学术会议暨第十二届全国生物流变学学术会议

作者： Jiu-ling Wang xing-hua shi Institute of Mechanics Chinese Academy of Sciences

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Probing mechanical principles of cell

清热解毒类中药抗病毒活性及作用机制研究进展

第十二届全国物理力学学术会议

作者： Jiu-Ling Wang xing-hua shi The State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of Sciences

Graphene-family nanomaterials(GFNs) including monolayer graphene,few-layer graphene, and ultrathin graphite nanosheets have potential applications for next generation microchips, composites,barrier coatings,biosensors,and drug *** are very thin,typically 1-30 graphene layers,but sheet-like or plate-like with lateral dimensions in the nm range up to several hundredμm similar to *** humans,inhalation or intravenous injection of plate-like minerals including talc,kaolinite,and mica induces lung granulomas which are formed in response to biopersistent foreign materials that are not readily engulfed and degraded by macrophages and are characteristics of the response to carbon nanotubes following intratracheal instillation or inhalation in *** nanotubes have also been shown to induce persistent inflammation and pulmonary fibrosis in ***-dimensional graphene nanomaterials are unique in comparison with spherical nanoparticles or one-dimensional nanotubes or nanorods and the chemical and physical determinants of the biological responses of macrophages and pulmonary toxicity are unknown. In this talk,we will discuss some recent studies on the mechanics of cell-GFNs interactions, including the mechanics of cellular uptake of GFNs by receptor-mediated endocytosis and coarsegrained molecular dynamics simulations of complete lipid bilayer segments interacting with GFNs. The discussions will be organized around the following *** and how does cellular uptake of GFNs depend on the particle size,shape,aspect ratio and elasticity? In particular, we will discuss the effect of elastic stiffness on cell-GFNs interactions and how two-dimensional nanomaterials such as GFNs enter cells.

关键词：

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

中国药理学通报 2014年第4期30卷 464-468页

作者：邢世华李晓波上海交通大学药学院上海200240

病毒是一类严重危害人类健康、威胁人类生命的病原体。具有传播迅速、死亡率高等特点。目前尚缺乏理想的抗病毒西药,而作为天然物品的中药,有很多种类对病毒有一定的抑制作用,成为近年来医学研究的热点。该文从清热解毒类中药抗病毒的... 详细信息

病毒是一类严重危害人类健康、威胁人类生命的病原体。具有传播迅速、死亡率高等特点。目前尚缺乏理想的抗病毒西药,而作为天然物品的中药,有很多种类对病毒有一定的抑制作用,成为近年来医学研究的热点。该文从清热解毒类中药抗病毒的实验研究及作用机制角度出发,阐明清热解毒类中药在抗病毒方面的重要作用,从而为临床筛选抗病毒中药提供依据。

关键词：清热解毒药抗病毒单味药有效成分中药复方实验研究作用机制

Resting-state brain network remodeling after different nerve reconstruction surgeries:a functional magnetic resonance imaging study in brachial plexus injury rats

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第5期20卷 1495-1504页

作者： Yunting Xiang Xiangxin xing Xuyun hua Yuwen Zhang Xin Xue Jiajia Wu Mouxiong Zheng He Wang Jianguang Xu School of Rehabilitation Science Shanghai University of Traditional Chinese MedicineShanghaiChina Engineering Research Center of Traditional Chinese Medicine Intelligent Rehabilitation Ministry of EducationShanghaiChina Department of Rehabilitation Medicine Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghaiChina Department of Traumatology and Orthopedics Yueyang Hospital of Integrated Traditional Chinese and Western MedicineShanghai University of Traditional Chinese MedicineShanghaiChina Institute of Science and Technology for Brain-Inspired Intelligence Fudan UniversityShanghaiChina Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence(Fudan University) Ministry of EducationShanghaiChina Human Phenome Institute Fudan UniversityShanghaiChina

Distinct brain remodeling has been found after different nerve reconstruction strategies,including motor representation of the affected ***,differences among reconstruction strategies at the brain network level have not been *** study aimed to explore intranetwork changes related to altered peripheral neural pathways after different nerve reconstruction surgeries,including nerve repair,endto-end nerve transfer,and end-to-side nerve ***–Dawley rats underwent complete left brachial plexus transection and were divided into four equal groups of eight:no nerve repair,grafted nerve repair,phrenic nerve end-to-end transfer,and end-to-side transfer with a graft sutured to the anterior upper ***-state brain functional magnetic resonance imaging was obtained 7 months after *** independent component analysis algorithm was utilized to identify group-level network components of interest and extract resting-state functional connectivity values of each voxel within the *** in intra-network resting-state functional connectivity were compared among the *** muscle reinnervation was assessed by behavioral observation(elbow flexion)and *** results showed that alterations in the sensorimotor and interoception networks were mostly related to changes in the peripheral neural *** repair was related to enhanced connectivity within the sensorimotor network,while end-to-side nerve transfer might be more beneficial for restoring control over the affected limb by the original motor *** thalamic-cortical pathway was enhanced within the interoception network after nerve repair and end-to-end nerve *** areas related to cognition and emotion were enhanced after end-to-side nerve *** study revealed important brain networks related to different nerve *** networks may be potential targets for enhancing motor recovery.

关键词： brain functional networks end-to-end nerve transfer end-to-side nerve transfer independent component analysis nerve repair peripheral plexus injury resting-state functional connectivity

Small extracellular vesicles derived from human induced pluripotent stem cell-differentiated neural progenitor cells mitigate retinal ganglion cell degeneration in a mouse model of optic nerve injury

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第2期20卷 587-597页

作者： Tong Li Hui-Min xing Hai-Dong Qian Qiao Gao Sheng-Lan Xu hua Ma Zai-Long Chi State Key Laboratory of Ophthalmology Optometry and Visual ScienceEye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina National Clinical Research Center for Ocular Diseases Eye HospitalWenzhou Medical UniversityWenzhouZhejiang ProvinceChina

Several studies have found that transplantation of neural progenitor cells(NPCs)promotes the survival of injured ***,a poor integration rate and high risk of tumorigenicity after cell transplantation limits their clinical *** extracellular vesicles(sEVs)contain bioactive molecules for neuronal protection and *** studies have shown that stem/progenitor cell-derived sEVs can promote neuronal survival and recovery of neurological function in neurodegenerative eye diseases and other eye *** this study,we intravitreally transplanted sEVs derived from human induced pluripotent stem cells(hiPSCs)and hiPSCs-differentiated NPCs(hiPSC-NPC)in a mouse model of optic nerve *** results show that these intravitreally injected sEVs were ingested by retinal cells,especially those localized in the ganglion cell *** with hiPSC-NPC-derived sEVs mitigated optic nerve crush-induced retinal ganglion cell degeneration,and regulated the retinal microenvironment by inhibiting excessive activation of *** analysis further revealed that hiPSC-NPC derived sEVs transported neuroprotective and anti-inflammatory miRNA cargos to target cells,which had protective effects on RGCs after optic nerve *** findings suggest that sEVs derived from hiPSC-NPC are a promising cell-free therapeutic strategy for optic neuropathy.

关键词： exosome miRNA neural progenitor cell neurodegeneration neuroinflammation neuroprotection optic nerve crush optic neuropathy retinal ganglion cell small extracellular vesicles

Low‑Temperature Oxidation Induced Phase Evolution with Gradient Magnetic Heterointerfaces for Superior Electromagnetic Wave Absorption

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2025年第1期17卷 191-204页

作者： Zizhuang He Lingzi shi Ran Sun Lianfei Ding Mukun He Jiaming Li hua Guo Tiande Gao Panbo Liu School of Chemistry and Chemical Engineering Northwestern Polytechnical UniversityXi’an 710129People’s Republic of China School of Marine Science and Technology Northwestern Polytechnical UniversityXi’an 710072People’s Republic of China

Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significant challenging in regulating local phase ***,accordion-shaped Co/Co_(3)O_(4)@N-doped carbon nanosheets(Co/Co_(3)O_(4)@NC)with gradient magnetic heterointerfaces have been fabricated via the cooperative high-temperature carbonization and lowtemperature oxidation *** results indicate that the surface epitaxial growth of crystal Co_(3)O_(4) domains on local Co nanoparticles realizes the adjustment of magnetic-heteroatomic components,which are beneficial for optimizing impedance matching and interfacial ***,gradient magnetic heterointerfaces simultaneously realize magnetic coupling,and long-range magnetic ***,the synthesized Co/Co_(3)O_(4)@NC absorbents display the strong electromagnetic wave attenuation capability of−53.5 dB at a thickness of 3.0 mm with an effective absorption bandwidth of 5.36 GHz,both are superior to those of single magnetic domains embedded in carbon *** design concept provides us an inspiration in optimizing interfacial polarization,regulating magnetic coupling and promoting electromagnetic wave absorption.

关键词： Magnetic heterointerfaces Phase evolution Interfacial polarization Magnetic coupling Electromagnetic wave absorption

Multiple Tin Compounds Modified Carbon Fibers to Construct Heterogeneous Interfaces for Corrosion Prevention and Electromagnetic Wave Absorption

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2025年第1期17卷 507-527页

作者： Zhiqiang Guo Di Lan Zirui Jia Zhenguo Gao Xuetao shi Mukun He hua Guo Guanglei Wu Pengfei Yin College of Science Sichuan Agricultural UniversityYa’an 625014People’s Republic of China School of Materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002People’s Republic of China Institute of Materials for Energy and Environment State Key Laboratory of Bio‑Fibers and Eco‑TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071People’s Republic of China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China

Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly ***-component interface engineering is considered an effective means to achieve high-efficiency EMW ***,interface modulation engineering has not been fully discussed and has great potential in the field of EMW *** this study,multi-component tin compound fiber composites based on carbon fiber(CF)substrate were prepared by electrospinning,hydrothermal synthesis,and high-temperature thermal *** utilizing the different properties of different substances,rich heterogeneous interfaces are *** effectively promotes charge transfer and enhances interfacial polarization and conduction *** prepared SnS/SnS_(2)/SnO_(2)/CF composites with abundant heterogeneous interfaces have and exhibit excellent EMW absorption properties at a loading of 50 wt%in epoxy *** minimum reflection loss(RL)is−46.74 dB and the maximum effective absorption bandwidth is 5.28 ***,SnS/SnS_(2)/SnO_(2)/CF epoxy composite coatings exhibited long-term corrosion resistance on Q235 steel ***,this study provides an effective strategy for the design of high-efficiency EMW absorbing materials in complex and harsh environments.

关键词： Electrostatic spinning Component regulation Heterogeneous interfaces Electromagnetic wave absorption Corrosion protection