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Mechanical behavior of entangled metallic wire materials-polyurethane interpenetrating composites

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Defence Technology（防务技术） 2023年第2期20卷 120-136页

作者： Xiao-yuan Zheng Zhi-ying Ren Hong-bai bai Zhang-bin Wu You-song Guo College of Mechanical Engineering and Automation Fuzhou UniversityFuzhou350116China Institute of Metal Rubber&Vibration Noise Fuzhou UniversityFuzhou350116China Gongbang Vibration Control Technology Co. LtdJiangsuJiangyin214431China

Composite materials exhibit the impressive mechanical properties of high damping and stiffness,which cannot be attained by employing conventional single *** these lines,a novel material architecture is presented in this work in order to fabricate composites with enhanced mechanical *** specifically,entangled metallic wire materials were used as the active matrix,whereas polyurethane was employed as the reinforcement *** a result,an entangled metallic wire material-polyurethane composite with high damping and stiffness was prepared by enforcing the vacuum infiltration *** top of that,the mechanical properties(loss factor,energy consumption,and average stiffness)of the proposed composite materials were characterized by performing dynamic tests,and its fatigue characteristics were verified by the micro-interface bonding,as well as the macro-damage *** impact of the density,preloading spacing,loading amplitude,and exciting frequency on the mechanical properties of the composites were also thoroughly *** extracted results indicate that the mechanical properties of the composites were significantly enhanced than those of the pure materials due to the introduction of interface ***,the average stiffness of the composites was about 10 times the respective value of the entangled metallic wire ***,a rise in the loading period leads to some failure between the composite interfaces,which reduces the stiffness property but enhances the damping dissipation ***,a comprehensive dynamic mechanical model of the composites was established,while it was experimentally *** proposed composites possess higher damping features,i.e.,stiffness characteristics,and maintain better fatigue characteristics,which can broaden the application range of the *** addition,we provide a theoretical and experimental framework for the research and applications in the field of metal ma

关键词： Entangled metallic wire material Composites materials Damping property Stiffness Fatigue characteristics

Experimental study on the microstructure and nanomechanicai properties of the wing membrane of dragonfly

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Acta Mechanica Sinica 2007年第3期23卷 281-285页

作者： Kewei Xiao Ke bai Wensheng Wang Fan song State Key Laboratory of Nonlinear Mechanics (LNM) Institute of Mechanics Chinese Academy of SciencesBeijing 100080 China Department of Chemical Biology School of Pharmaceutical SciencesPeking University Health Science CenterBeijing 100083 China Department of Mechanical Engineering Tongji University Shanghai 200092 China

Detailed investigations on the microstructure and the mechanical properties of the wing membrane of the dragonfly are carried out. It is found that in the direction of the thickness the membrane was divided into three layers rather than a single entity as traditionally considered, and on the surfaces the membrane displays a random distribution rough microstructure that is composed of numerous nanometer scale columns coated by the cuticle wax secreted. The characteristics of the surface structure are measured and described. The mechanical properties of the membranes taken separately from the wings of live and dead dragonflies are investigated by the nanoindentation technique. The Young＇s moduli obtained here are approximately two times greater than the previous result, and the reasons that yield the difference are discussed.

关键词： Microstructure Surface structure Mechanical properties Surface analysis

Study on the hydrogen absorption properties of a YGdTbDyHo rare-earth high-entropy alloy

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 127-135页

作者： Tongyue Li Ziliang Xie Wenjiao Zhou Huan Tong Dawen Yang Anjia Zhang Yuan Wu Xiping song State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China Whole Win(Beijing)Materials Sci.&Tech.Co. Ltd.Beijing 100083China

This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),*** indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed *** hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase *** alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).Without any activation,the YGdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period *** reason for the obtained value of 2.33 H/M was that the hydrogen atoms occupied both tetrahedral and octahedral *** results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/M ratio,which can be used in the deuterium storage field.

关键词： rare-earth high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves kinetics

The Classification of Carbon Dots and the Relationship between Synthesis Methods and Properties

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Chinese Journal of Chemistry 2023年第17期41卷 2206-2216页

作者： Xin-Xiang Zhao song-Yuan Tao bai Yang State Key Laboratory of Supramolecular Structure and Materials Collegeof ChemistryJilin UniversityChangchunJilin 130012China

Comprehensive Summary,The carbon dots(CDs),as emerging carbon based nanomaterials,are a kind of fluorescent materials with wide application *** luminous CDs can simply be synthesized by a wide variety of easily accessible *** have excellent optical properties,high biocompatibility and low toxicity,which makes them be used in the fields of optics,biology,energy,and so *** this review,the classification,nomenclature,photoluminescence mechanism and property regulation of CDs are ***.

关键词： Nanoparticles Nanostructures Luminescence Fluorescence Polymerization Carbon dots Classification and nomenclature Structure and performance

Crystal structure and negative thermal expansion of solid solution Lu_2W_(3-x)Mo_xO_(12)

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International Journal of Minerals,Metallurgy and Materials 2010年第6期17卷 786-790页

作者： Jie peng Xin-zhi Liu Fu-li Guo song-bai Han Yun-tao Liu Dong-feng Chen Zhong-bo Hu Experimental Physics Center Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China College of Chemistry and Chemical Engineering Graduate University of Chinese Academy of Sciences Beijing 100049 China China Institute of Atomic Energy Beijing 102413 China College of Chemistry Beijing Normal University Beijing 100875 China

A new series of solid solutions Lu2W3-xMoxO12 （0.5≤r≤2.5） were successfully synthesized by the solid-state method. Their crystal structure and negative thermal expansion properties were studied using high-temperature X-ray powder diffraction and the Rietveld method. All samples of rare-earth ttmgstates and molybdates are found to crystallize in the same orthorhombic structure with space group Pnca and show the negative thermal expansion phenomena related to transverse vibration of bridging oxygen atoms in the structure. Thermal expansion coefficients （TEC） of Lu2W3_xMoxO12 are determined as -20.0× 10^-6 K^-1 for x=0.5 and -16.1×10^-6 K^-1 for x=2.5 but -18.6× 10^-6 and -16.9× 10^-6K^-1 for unsubstituted Lu2W3012 and Lu2M03012 in the identical temperature range of 200 to 800℃. High-temperature X-ray diffraction （XRD） data and bond length analysis suggest that the difference between W-O and Mo-O bond is responsible for the change of TECs after the element substitution in this series of solid solutions.

关键词： rare earth compounds molybdates rare-earth tungstates negative thermal expansion X-ray diffraction

FUBP3 mediates the amyloid-β-induced neuronal NLRP3 expression

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Neural Regeneration Research 2025年第7期20卷 2068-2083页

作者： Jing Yao Yuan Li Xi Liu Wenping Liang Yu Li Liyong Wu Zhe Wang Weihong song The National Clinical Research Center for Geriatric Disease Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Neurology The First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina Department of Neurosurgery Xuanwu HospitalCapital Medical UniversityBeijingChina Department of Pediatrics The Second Affiliated Hospital and Yuying Children’s HospitalKey Laboratory of Alzheimer’s Disease of Zhejiang ProvinceInstitute of AgingWenzhou Medical UniversityWenzhouZhejiang ProvinceChina Oujiang Laboratory(Zhejiang Laboratory for Regenerative Medicine Visionand Brain Health)WenzhouZhejiang ProvinceChina

Alzheimer's disease is characterized by deposition of amyloid-β,which forms extracellular neuritic plaques,and accumulation of hyperphosphorylated tau,which aggregates to form intraneuronal neurofibrillary tangles,in the *** NLRP3 inflammasome may play a role in the transition from amyloid-βdeposition to tau phosphorylation and *** NLRP3 is primarily found in brain microglia,and tau is predominantly located in neurons,it has been suggested that NLRP3 expressed by microglia indirectly triggers tau phosphorylation by upregulating the expression of pro-inflammatory ***,we found that neurons also express NLRP3 in vitro and in vivo,and that neuronal NLRP3 regulates tau *** biochemical methods,we mapped the minimal NLRP3 promoter and identified FUBP3 as a transcription factor regulating NLRP3 expression in *** primary neurons and the neuroblastoma cell line Neuro2A,FUBP3 is required for endogenous NLRP3 expression and tau phosphorylation only when amyloid-βis *** the brains of aged wild-type mice and a mouse model of Alzheimer's disease,FUBP3 expression was markedly increased in cortical *** analysis suggested that FUBP3 plays a role in neuron-mediated immune *** also found that FUBP3 trimmed the 5′end of DNA fragments that it bound,implying that FUBP3 functions in stress-induced *** findings suggest that neuronal NLRP3 may be more directly involved in the amyloid-β-to–phospho-tau transition than microglial NLRP3,and that amyloid-βfundamentally alters the regulatory mechanism of NLRP3 expression in *** that FUBP3 was only expressed at low levels in young wild-type mice and was strongly upregulated in the brains of aged mice and Alzheimer's disease mice,FUBP3 could be a safe therapeutic target for preventing Alzheimer's disease progression.

关键词： 5′end trimming Alzheimer's disease amyloid-beta amyloid-β-dependent transcription FUBP3 inflammasome inflammation neuron NLRP3 tau transcription factor

Survey on Path-Dependent PDEs

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Chinese Annals of Mathematics,Series B 2023年第6期44卷 837-856页

作者： Shige peng Yongsheng song Falei WANG School of Mathematics Zhongtai Securities Institute for Financial StudiesShandong UniversityJinan 250100China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China Zhongtai Securities Institute for Financial Studies School of MathematicsShandong UniversityJinan 250100China

In this paper,the authors provide a brief introduction of the path-dependent partial differential equations(PDEs for short)in the space of continuous paths,where the path derivatives are in the Dupire(rather than Fréchet)*** present the connections between Wiener expectation,backward stochastic differential equations(BSDEs for short)and path-dependent *** also consider the well-posedness of path-dependent PDEs,including classical solutions,Sobolev solutions and viscosity solutions.

关键词： Path-Dependent Wiener expectation BSDEs Classical solution Sobolev solution Viscosity solution

Preparation and Spectroscopic Study of Different Stoichiometric Solid Supramolecular Inclusion Complexes of β-Cyclodextrin with Short Chain Aliphatic Amines

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Chinese Journal of Chemical Physics 2008年第2期21卷 174-180页

作者： Le-xin song Chuan-feng Teng Hai-ming Wang Lei bai Department of Chemistry University of Science and Technology of China Hefei 230026 China

The solid Supramolecular complexes of β-cyclodextrin （β-CD） with ethylenediamine 1, diethylenetriamine 2 and triethylamine 3 were obtained and characterized using elemental analysis, powder X-ray diffraction, infrared spectroscopy, thermogravimetric analysis, and ^1H nuclear magnetic resonance spectroscopy. Based on the results of elemental analysis and ^1H NMR, the guest-host stoichiometries of the three solid complexes were determined to be 5：2 for 1-β-CD, hl for 2-β-CD, and 1：3 for 3-β-CD. The yields were relative to the molar volume ratio of guest to β-CD cavity, and increased in the order： 1-β-CD〈2-3-CD〈3-β-CD. X-ray diffraction patterns of the inclusion complexes gave very good exhibitions not only in location of diffraction peaks but also in shape and diffraction intensity of the peaks due to the intermolecular complexations between β-CD and the guests. The formation of host-guest inclusion complexes exhibited obviously enhanced phase change temperatures of the complexed guests such as 1 and 3. The H-5 protons located at the narrower rim inside the CD cavity experienced a higher shift upon inclusion while all other protons experienced lower shifts.

关键词： β-cyclodextrin Inclusion complex Ethylenediamine Supramolecular

Cooperative Sampling Path Planning of Underwater Glider Fleet with Simultaneous Launch and Recovery

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Journal of Ocean University of China 2023年第4期22卷 975-982页

作者： ZANG Wenchuan song Dalei YAO peng College of Information Science and Engineering Ocean University of ChinaQingdao 266000China Department of Electronics Information and BioengineeringPolitecnico di MilanoMilan 20133Italy College of Engineering Ocean University of ChinaQingdao 266000China

As low-cost and highly autonomous ocean observation platforms,underwater gliders encounter risks during their launch and recovery,especially when coordinating multi-glider *** work focuses on cooperative path planning of an underwater glider fleet with simultaneous launch and recovery to enhance the autonomy of sampling and reduce deployment ***,the gliders collaborate to achieve sampling considering the specified routines of *** overall paths to be planned are divided into four rectangular parts with the same starting point,and each glider is assigned a local sampling route.A clipped-oriented line-of-sight algorithm is proposed to ensure the coverage of the desired *** pitch angle of the glider is selected as the optimizing parameter to coordinate the overall progress considering the susceptibility of gliders to currents and the randomness of paths produced by complex navigational ***,a multi-actuation deep-Q network algorithm is proposed to ensure simultaneous launch and *** results demonstrate the acceptable effectiveness of the proposed method.

关键词： underwater glider fleet cooperative sampling path planning simultaneous launch and recovery clipped-oriented line-ofsight multi-actuation deep-Q network