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First-Principles Study of Phase Stability and Mechanical Property of Co_3(Al,W) Precipitates with Different Ratio of Al to W in Co Base Alloys

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稀有金属材料与工程 2009年第A03期38卷 1-4页

作者： Yao q Su X M Yan Y Zhao L W sun J Shanghai Jiaotong University Shanghai 200240 China

The energetics, electronic structure and mechanical property of Co3(Al,W) precipitates with different ratio of Al to W in Co base alloys were investigated by the method of supercell and augmented plane waves plus local orbitals within generalized gradient approximation. The calculated results show that the L12 Co3(Al,W) precipitate is the most stable when the ratio of Al to W is equal to 1. When the content of W is higher than 18.5 at%, the L12 and hexagonal structures co-exist in Co3(Al,W) precipitates at 1173 K. It is also shown that the L12 ordered Co3(Al,W) precipitates have an obvious strengthening effect in the disordered fcc cobalt matrix.

关键词：铝电子结构力学性能碳酸

TETRABUTYLAMMONIUM－TETRACYANOqUINODIMETHANE　AS　ELECTRON－TRANSFER　MEDIATOR　IN　AMPEROMETRIC　GLUCOSE　SENSOR

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Chinese Chemical Letters 1995年第2期6卷 141-142页

作者： sun, Cq Song, WB Zhao, D Gao, q Xu, HD Jilin Univ Dept Chem Changchun 130023 Peoples R China

The design and testing of amperometric glucose biosensor was described, in which electrical communication between the flavin redox centers of glucose oxidase and a conventional carbon paste electrode has been achieved by using electron-transfer mediator based on tetrabutylammonium-tetra-cyanoquinodimethane(TBA+-TCNq-). Characteristics of the biosensor has been shown by cyclic voltammetry. The experimental results show that TBA+-TCNq- can act as an efficient electron transfet mediator between GODox/GODred centers and a carbon paste electrode.

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Fingerprint Liveness Detection from Different Fingerprint Materials Using Convolutional Neural Network and Principal Component Analysis

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Computers, Materials & Continua 2017年第4期53卷 357-372页

作者： Chengsheng Yuan Xinting Li q.M.Jonathan Wu Jin Li Xingming sun School of Computer and Software Nanjing University of Information Science&TechnologyNing Liu RoadNo.219NanjingChina210044 Jiangsu Engineering Center of Network Monitoring Ning Liu RoadNo.219NanjingChina210044 Department of Electrical and Computer Engineering University of Windsor401 Sunset AvenueWindsorONCanada N9B 3P4 School of Computer Science Guangzhou UniversityYudongxi Road 36Tianhe DistrictGuangzhouChina510500

Fingerprint-spoofing attack often occurs when imposters gain access illegally by using artificial fingerprints,which are made of common fingerprint materials,such as silicon,latex,***,to protect our privacy,many fingerprint liveness detection methods are put forward to discriminate fake or true *** work on liveness detection for fingerprint images is focused on the construction of complex handcrafted features,but these methods normally destroy or lose spatial information between *** from existing methods,convolutional neural network(CNN)can generate high-level semantic representations by learning and concatenating low-level edge and shape features from a large amount of labeled ***,CNN is explored to solve the above problem and discriminate true fingerprints from fake ones in this *** reduce the redundant information and extract the most distinct features,ROI and PCA operations are performed for learned features of convolutional layer or pooling *** that,the extracted features are fed into SVM *** results based on the LivDet(2013)and the LivDet(2011)datasets,which are captured by using different fingerprint materials,indicate that the classification performance of our proposed method is both efficient and convenient compared with the other previous methods.

关键词： Fingerprint liveness detection CNNs PCA SVM ROI LivDet 2013 LivDet 2011

Design and Pilot Programs of Marine Exposure Station of A Sea-crossing Bridge

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武汉理工大学学报 2010年第17期32卷 131-136页

作者： qIN M q WANG C J TU L q ZHANG G Z sun T X Wuhan Harbour Engineering Design and Research Co. Ltd. Wuhan 430071China Key Lab of Large-span Bridge Construction Technology Ministry of CommunicationsWuhan 430071China Zhejiang Province Zhoushan Island Linking Construction Commanding Department Zhoushan 316032China School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

This paper presents the Location,the structural design as well as the anti-corrosion and the pilot programs of the marine exposure station of Zhoushan Archipelago seas sea-crossing bridges. Subjected to the marine environment,the concrete structures in serve with different mixing proportions,cover thickness,additional anti-corrosion measures such as rust-preventing agent,coating,penetration crystalline waterproof material,silicone and permeable fabric were studied. Those results obtained provide important information for the maintenance of marine concrete and the structural design of sea-crossing bridges in the above sea area.

关键词： exposure station sea-crossing bridge marine concrete durability design

Improvement of Coercivity and Corrosion Resistance of Nd-Fe-B Sintered Magnets with Cu Nano-particles Doping

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Journal of Materials Science & Technology 2012年第10期28卷 927-930页

作者： C.sun W.q.Liu H.sun M.Yue X.F.Yi J.W.Chen College of Materials Science and Engineering Beijing University of TechnologyBeijing 100124China Earth-panda Advance Magnetic Material Co. Ltd.Anhui 231500China

Nd-Fe-B permanent magnets with a small amount of Cu nano-particles doping have been prepared by con-ventional sintered method. Effects of Cu content on magnetic properties, corrosion resistance, and oxidation properties of the magnets have been studied. It shows that the coercivity rises gradually, while the remanence decreases simultaneously with increasing Cu doping amount. Microstructure observation reveals that Cu ele- ment enriches mainly the Nd-rich phase. Autoclave test results show that the corrosion rate of the magnets decreases with increasing Cu content. After oxidation, the maximum energy product loss of the magnets with 0 and 0.2 wt% Cu nano-particles doping are 6.13% and 0.g9%, respectively. Therefore, it is concluded that Cu nano-particles doping is a promising way to enhance the coercivity and corrosion resistance of sintered Nd-Fe-B magnets.

关键词： Nd-Fe-B Cu nano-particles Coercivity Corrosion resistance Oxidation

MODIFICATION OF SURFACE MECHANICAL PROPERTIES OF POLYCARBONATE BY B^+ AND O^+ IONS IMPLANTATION

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Acta Metallurgica Sinica(English Letters) 2002年第1期15卷 33-38页

作者： S.D. Yao C. sun S.q. Zhou C.C. sun Y.H. Lu L. Huang A. Vantomme q. Zhao G. Langouche School of Physics Peking University Beijing 100871 China College of Chemistry and Molecular Enginearing Peking University Beijing 100871 China Instituut Voor Kern-en Stralingsfysika University of Leuven B-3001 Leuven Belgium

By implanting B+ and O+ ions respectively into polycarbonate (PC) plates, the surface mechanical properties of PC have been improved. Measurement by Nano Indenter II showed that the hardness of samples increased 7-25 times than that before implantation; and the modulus of elasticity raised 2-5 times. The wear-resistance was tested by ball crusher; the width and depth of the wear-streak decreased by 1/3-1/2 or even more. The structure, deformation and appearance were analyzed by using Micro-FTIR Spectra, ESCA method and the steps instrument. These analyses showed that the structure of PC had been modified: a series of new cross-linking yielded, it depends on the Linear Energy Transition (LET) of implanted ions in the high polymer compounds.

关键词： polycarbonate ion implantation surface modification

Polybenzimidazolium-reinforced polyimide separators to inhibit dendrites for high-security lithium-ion batteries

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Science China Chemistry 2025年

作者： Guohua sun Jiaqi Cui qingsong Zhang Yisong Zhou Xinluo Li Yingying Zhang Zhanao Zhang Xin Zhang Jiantao Fan Pengpeng Li Lianlong Hou Nanjun Chen Hebei Key Laboratory of Flexible Functional Materials School of Materials Science and Engineering Hebei University of Science and Technology State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical Technology Academy for Advanced Interdisciplinary Studies Southern University of Science and Technology State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical Engineering Xiamen University

Lithium dendrite formation poses a significant safety hazard in lithium-ion batteries（LIBs）, severely impeding their widespread adoption and further technological advancements. Here, we present a novel quaternized polybenzimidazolium（q-PBI） to armor polyimide（PI） nanofiber separator（q-PBI@PI）, in which the q-PBI containing lithiophilicity and anionphilicity sites serves as the multifunctional nano-layers to suppress the Li dendrite and reinforce the mechanical properties of PI nanofiber ***, the q-PBI@PI separator displays an unprecedented mechanical strength of 82.8 MPa, significantly outperforming previously reported PI nanofiber membranes（typically below 50.0 MPa）. Besides, we demonstrate that the q-PBI@PI separator simultaneously possesses low nucleation overpotential（59 mV） and exceptional average coulombic efficiency due to the suppression of Li dendrite. Importantly, q-PBI@PI-based Li||Li battery enables a stable Li plating-stripping at 1.0 m A cm-2for600 h. Attributing to these exceptional merits, the armored PI separator-based LIBs display remarkable specific capability and capacity retention. The density function theory calculations reveal that q-PBI is conducive to the desolvation of Li+and can immobilize Li+and PF6-ions near affinity sites of PI nanofibers for inhibiting the formation of Li dendrites. Our work paves a new avenue for the design of next-generation high-performing separators in LIBs.

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Pulsed Microfluid Force-Based On-Chip Modular Fabrication for Liver Lobule-Like 3D Cellular Models

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Cyborg and Bionic Systems 2021年第1期2021卷 222-233页

作者： J.Cui H.P.Wang q.Shi T.sun Science and Technology on Electronic Test and Measurement Laboratory North University of ChinaTaiyuan 030051China Intelligent Robotics Institute School of Mechatronical EngineeringBeijing Institute of TechnologyBeijing 100081China Beijing Advanced Innovation Center for Intelligent Robots and Systems Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Biomimetic Robots and Systems(Beijing Institute of Technology) Ministry of EducationBeijing 100081China

In vitro three-dimensional(3D)cellular models with native tissue-like architectures and functions have potential as alternatives to human tissues in regenerative medicine and drug ***,it is difficult to replicate liver constructs that mimic in vivo microenvironments using current approaches in tissue engineering because of the vessel-embedded 3D structure and complex cell distribution of the *** paper reports a pulsed microflow-based on-chip 3D assembly method to construct 3D liver lobule-like models that replicate the spatial structure and functions of the liver *** heterogeneous cell-laden assembly units with hierarchical cell distribution are fabricated through multistep photopatterning of different cell-laden *** fluid force interaction by pulsed microflow,the hierarchical assembly units are driven to a stack,layer by layer,and thus spatially assemble into 3D cellular models in the closed liquid chamber of the assembly *** 3D models with liver lobule-like hexagonal morphology and radial cell distribution allow the dynamic perfusion culture to maintain high cell viability and functional expression during long-term culture in *** results demonstrate that the fabricated 3D liver lobule-like models are promising for drug testing and the study of individual diagnoses and treatments.

关键词： culture maintain spatially

Nonlinear mechanics of a ring structure subjected to multi-pairs of evenly distributed equal radial forces

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Acta Mechanica Sinica 2017年第5期33卷 942-953页

作者： q. Chen F. sun Z. Y. Li L. Taxis N. Pugno Biomechanics Laboratory School of Biological Science and Medical Engineering Southeast University State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics School of Chemistry Physics and Mechanical EngineeringQueensland University of Technology (QUT) Laboratory of Bio-Inspired and Graphene Nanomechanics Department of Civil Environmental and Mechanical Engineering University of Trento School of Engineering and Materials Science Queen Mary University of London Ket Lab Italian Space Agency Via del Politecnico snc

Combining the elastica theory, finite element (FE) analysis, and a geometrical topological experiment, we studied the mechanical behavior of a ring subjected to multi-pairs of evenly distributed equal radial forces by looking at its seven distinct states. The results showed that the theoretical predictions of the ring deformation and strain energy matched the FE results very well, and that the ring deformations were comparable to the topological experiment. Moreover, no matter whether the ring was compressed or tensioned by N-pairs of forces, the ring always tended to be regular polygons with 2N sides as the force increased, and a proper compressive force deformed the ring into exquisite flower-like patterns. The present study solves a basic mechanical problem of a ring subjected to lateral forces, which can be useful for studying the relevant mechanical behavior of ring structures from the nano- to the macro-scale.

关键词： Ring structures Mechanical properties Shape Strain energy