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A delayed reaction–diffusion viral infection model with nonlinear incidences and cell-to-cell transmission

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International Journal of Biomathematics 2021年第8期14卷 305-342页

作者： qing ge Xia Wang Libin Rong School of Mathematics and Statistics XinyangNormal UniversityXinyang 464000P.R.China Department of Mathematics University of FloridaGainesvilleFL 32611USA

In this paper,we propose a reaction–diffusion viral infection model with nonlinear incidences,cell-to-cell transmission,and a time *** impose the homogeneous Neumann boundary *** the case where the domain is bounded,we first study the *** we analyze the local stability of homogeneous steady *** establish a threshold dynamics which is completely characterized by the basic reproduction *** the case where the domain is the whole Euclidean space,we consider the existence of traveling wave solutions by using the cross-iteration method and Schauder’s fixed point ***,we study how the speed of spread in space affects the spread of cells and *** obtain the existence of the wave speed,which is dependent on the diffusion coefficient.

关键词： Reaction-diffusion equation cell-to-cell transmission absorption effect time delay traveling wave solutions

Comparison of Biotribology of Swine Compact Bone Against UHMWPE

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Journal of China University of Mining and Technology 2007年第1期17卷 133-137页

作者： WANG qing-liang ge Shi-rong School of Materials Science and Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

A pin-on-disk tribometer was used, in a comparative test to observe the tribological behavior of the swine femoral bone against UHMWPE with dry friction, physiological water and human plasma lubrication. The wear mechanisms of swine bones and UHMWPE were investigated by SEM. The experimental results of these wear tests demon- strated that both the friction coefficient and wear rate of UHMWPE were the lowest when human plasma lubrication was used. The wear mechanism of the compact bone was mainly fatigue wear with dry friction, corrosive wear under physiological water lubrication and abrasive wear with human plasma lubrication. For UHMWPE, the wear mecha- nism was adhesive wear and plastic deformation with dry friction, serious ploughing and fatigue fracture wear under physiological water lubrication, fine ploughing and plastic deformation with human plasma lubrication. An analysis of nitrogen elements on the wear surface of UHMWPE indicated that the content of nitrogen in worn areas was 16 times higher than that in unworn areas, which proved that serum protein deposition occurred on worn areas.

关键词： swine bone UHMWPE friction and wear wear mechanism

Thymic iNKT cell differentiation at single-cell resolution

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Cellular & Molecular Immunology 2021年第8期18卷 2065-2066页

作者： Ke Wang Weijia Zhao Rong Jin qing ge Department of Immunology School of Basic Medical SciencesPeking UniversityNHC Key Laboratory of Medical Immunology(Peking University)BeijingChina Department of Integration of Chinese and Western Medicine School of Basic Medical SciencesPeking UniversityBeijingChina

Recently,Baranek et *** single-cell RNA sequencing(scRNA-seq)analysis and confirmed some of the transcriptomic results by in vitro cell culture with IL-7/IL-15 and flow cytometric analysis.2 The authors defined several intermediate stages,including iNKT2a(CD24−NK1.1−CD138−FR4−),iNKT2b(CD24−NK1.1−CD138−FR4+),and iNKT1a(CD24−Sca-1hiCD138-NK1.1dim),with various degrees of potential to differentiate into iNKT1,iNKT2,and iNKT17 subsets(Fig.1).

关键词： CD24 CD138 NKT cell

Influence of rapid heating process on the microstructure and tensile properties of high-strength ferrite–martensite dual-phase steel

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International Journal of Minerals,Metallurgy and Materials 2015年第9期22卷 933-941页

作者： Pei Li Jun Li qing-ge Meng Wen-bin Hu Chun-fu Kuang School of Material Science and Engineer Shanghai Jiao Tong University Research Institute of Baoshan Iron and Steel Co. Ltd School of Material Science and Engineer University of Science and Technology Beijing

Three low-carbon dual-phase （DP） steels with almost constant martensite contents of 20vo1% were produced by intercritical annealing at different heating rates and soaking temperatures. Microstructures prepared at low temperature （1043 K, FH1） with fast-heating （300 K/s） show banded ferrite/martensite structure, whereas those soaked at high temperature （1103 K, FH2） with fast heating reveal blocky martensite uniformly distributed in the fine-grained ferrite matrix. Their mechanical properties were tested under tensile conditions and compared to a slow-heated （5 K/s） reference material （SH0）. The tensile tests indicate that for a given martensite volume fraction, the yield strength and total elongation values are noticeably affected by the refinement of ferrite grains and the martensite morphology. Metallographic observations reveal the formation of microvoids at the ferrite/martensite interface in the SH0 and FH2 samples, whereas microvoids nucleate via the fracture of banded martensite particles in the FH1 specimen. In addition, analyses of the work-hardening behaviors of the DP microstructures using the differential Crussard-Jaoul technique demonstrate two stages of work hardening for all samples.

关键词： high-strength steel martensite ferrite heating microstructure tensile properties grain refinement

Microstructure Characterization and Mechanical Properties of TRIP-aided Steel under Rapid Heating for Different Holding Time

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Journal of Iron and Steel Research International 2016年第2期23卷 138-144页

作者： De-chao XU Yan-dong LIU Jun LI qing-ge MENG Pei LI School of Materials and Metallurgy Northeastern UniversityShenyang 110819LiaoningChina Central Research Institute of Baosteel Shanghai 201900China Shanghai JiaoTong University Shanghai 200240China

In order to develop a comprehensive understanding about the effect of different holding time under rapid heating on the microstructural evolution and mechanical properties of transformation-induced plasticity （TRIP） steel, continuous annealing process simulations were performed using a thermal system with resistance heating method. The morphology and distribution of all phases present in the microstructure and the mechanical properties of TRIP steel were revealed. It appeared that the final tensile strength of the TRIP steel increased and retained austenite car bon content decreased with increasing holding time. An overlap between ferrite recrystallization and austenitization was observed during intercritical holding. In addition, the work hardening of the samples was evaluated by calculat ing the instantaneous ~l value as a function of the true strain. The difference in work hardening behavior corresponds to the rate of the retained austenite transformation during straining, which can be attributed to the carbon content and the morphology of the retained austenite.

关键词： TRIP-aided steel rapid heating holding time austenite formation retained austenite

MTTSNet:Military time-sensitive targets stealth network via real-time mask generation

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Defence Technology（防务技术） 2024年第3期33卷 601-612页

作者： Siyu Wang Xiaogang Yang Ruitao Lu Zhengjie Zhu Fangjia Lian qing-ge Li Jiwei Fan PLA Rocket Force University of Engineering Xi'an 710025China

The automatic stealth task of military time-sensitive targets plays a crucial role in maintaining national military security and mastering battlefield dynamics in military *** propose a novel Military Time-sensitive Targets Stealth Network via Real-time Mask generation(MTTSNet).According to our knowledge,this is the first technology to automatically remove military targets in real-time from *** critical steps of MTTSNet are as follows:First,we designed a real-time mask generation network based on the encoder-decoder framework,combined with the domain expansion structure,to effectively extract mask ***,the ASPP structure in the encoder could achieve advanced semantic feature *** decoder stacked high-dimensional information with low-dimensional information to obtain an effective mask ***,the domain expansion module guided the adaptive expansion of mask ***,a context adversarial generation network based on gated convolution was constructed to achieve background restoration of mask positions in the original *** addition,our method worked in an end-to-end manner.A particular semantic segmentation dataset for military time-sensitive targets has been constructed,called the Military Time-sensitive Target Masking Dataset(MTMD).The MTMD dataset experiment successfully demonstrated that this method could create a mask that completely occludes the target and that the target could be hidden in real time using this *** demonstrated the concealment performance of our proposed method by comparing it to a number of well-known and highly optimized baselines.

关键词： Deep learning Military application Targets stealth network Mask generation generative adversarial network

Preparation and Structure-Property Regulation Mechanism of Reversible Thermochromic Polydiacetylene

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Chinese Journal of Polymer Science 2024年第8期42卷 1111-1121页

作者： Zhi-qing ge Shuo Yan Zu-Xiong Pan Shan Lei Xuan-Zhi Mao Chu Zhao Mo-Zhen Wang Xue-Wu ge Key Laboratory of Precision and Intelligent Chemistry Department of Polymer Science and EngineeringUniversity of Science and Technology of ChinaHefei 230026China Marshall Laboratory of Biomedical Engineering International Cancer CenterLaboratory of Evolutionary Theranostics(LET)School of Biomedical EngineeringShenzhen University Medical SchoolShenzhen UniversityShenzhen 518055China Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China

The thermochromic mechanism and the structure-property regulation principle of reversible thermochromic polydiacetylene(PDA)materials have always been a challenging *** this work,a series of diacetylene monomers(m-PCDA)containing phenyl and amide or carboxyl groups were synthesized from 10,12-pentacosadiynoic acid(PCDA)through the esterification or amidation *** effects of the number and the distribution of the functional groups in m-PCDA molecules on their solid-state polymerization capability,and the thermochromic mechanism of their corresponding polymers(m-PDA)were investigated and discussed in *** results show that the m-PCDA monomers containing both benzene ring and groups that can form hydrogen bonding interactions have strong intermolecular interaction,and are easy to carry out the solid phase polymerization under 254-nm UV irradiation to obtain the corresponding new thermochromic m-PDA *** thermochromic behavior of m-PDA depends on its melting *** initial color-change temperature(blue to red)is determined by the onset melting tem perature,and the temperature range in which reversible color recovery can be achieved by repeat heating-cooling treatment is determined by its melting *** to the proposed thermochromic mechanism of PDA,various new PDA materials with precise thermochromic temperatu res and reversible thermochromic temperature ra nges can be designed and synthesized through the appropriate introduction of benzene ring and groups that can form hydrogen bonding interactions into the molecular structure of linear diacetylene *** work provides a perspective to the precise molecular structure design and the property regulation of the reversible thermochromic PDA materials.

关键词： Polydiacetylene Thermochromism Hydrogen bonding Chemical modification

Thermodynamics of Molten Pool Predicted by Computational Fluid Dynamics in Selective Laser Melting of Ti6Al4V:Surface Morphology Evolution and Densification Behavior

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Computer Modeling in Engineering & Sciences 2020年第9期124卷 1085-1098页

作者： Donghua Dai Dongdong Gu qing ge Chenglong Ma Xinyu Shi Han Zhang College of Materials Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing210016China Jiangsu Provincial Engineering Laboratory for Laser Additive Manufacturing of High-Performance Metallic Components Nanjing University of Aeronautics and AstronauticsNanjing210016China

The three-dimensional physical model of the randomly packed powder material irradiated by the laser beam was established,taking into account the transformation of the material phase,the melt spreading and the interaction of the free surface of the molten pool and the recoiling pressure caused by the material evaporation during the selective laser *** of the processing parameters on the thermal behavior,the material evaporation,the surface morphology and the densification behavior in the connection region of the molten pool and the substrate was *** was shown that the powder material underwent the transformation from the partial melting state to the complete melting state and finally to the overheating state with the applied laser energy density increasing from 167 J/mm^(3) to 417 J/mm^(3).Therefore,the solidified track ranged from the discontinuous tracks with the rough surface to the continuous tracks with residual porosities,then to the continuous and dense tracks and terminally to the fluctuated tracks with the increase in the laser energy ***,the laser energy effect depth was maintained the positive relationship with the laser energy *** vortex velocity obtained in the free surface of the molten pool towards to the rear region in the opposite laser scan direction promoted the melt convection to the edge region of the molten pool as the laser energy density was higher than 277 J/mm^(3),demonstrating the efficient energy dissipation from the center of the irradiation region to the whole part of the molten pool and the attendant production of the sufficient melt ***,the efficient spreading of the molten pool and the metallurgical bonding ability of the melt with the substrate was obtained at the optimized laser energy density of 277 J/mm^(3).However,the severe material evaporation would take place as the melt was overheated,resulting in the formation of the residual pores and poor surface quality.

关键词： Additive manufacturing melt convection surface morphology densification behavior numerical simulation

Fabrication of immobilized nickel nanoclusters decorated by CxNy species for cellulose conversion to C2,3 oxygenated compounds:Rational design via typical C-and N-sources

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Journal of Energy Chemistry 2020年第11期29卷 25-36页

作者： Zhuqian Xiao Xiaolei Wang Qinqin Yang Chuang Xing qing ge Xikun Gai Jianwei Mao Jianbing Ji Zhejiang Provincial Collaborative Innovation Center of Agricultural Biological Resources Biochemical Manufacturing Zhejiang University of Science and TechnologyHangzhou 310023ZhejiangChina School of Chemical Engineering Zhejiang University of TechnologyHangzhou 310023ZhejiangChina

Production of chemicals and fuels from microcrystalline cellulose has inspired scholars’ attention. Deactivation of metallic catalysts including acid leaching and hydrothermal aggregation is still one of the core issues in these systems. To address these problems, we designed and fabricated a series of Ni-W/SiO2 catalysts, which were decorated by CxNy species using C-and N- sources and applied in cellulose conversion to C2,3 oxygenated compounds. The Ni-W/SiO2@CxNy catalysts, underwent complexing and selfassembling process, exhibited special heterojunctions, accompanying strong interactions mainly among Ni phase and CxNy layers. Catalytic results showed that the heterojunctions and outer CxNy layers extensively enhanced productions of hydroxyacetone(HDA) and ethylene glycol(EG) and promoted the hydrothermal stability through prospering in concentration of Lewis pairs from Ni–N—N structure and immobilizing the metallic nanoclusters. 48.25% of EG was yielded under 5.0 MPa H2 pressurized 240 ℃ water for 2.0 h. The Lewis pair further improved the formation of HDA with 20.92% yield. High hydrothermal stability of NiW/SiO2@CxNy catalyst was proved according to the recycling results and trace leaching concentration of Ni and W. This construction of metallic catalysts exploited a new strategy to manufacture extraordinary durability of metallic nanoclusters for cellulose conversion under harsh reaction conditions.

关键词： Cellulose Heterojunction Metallic immobilization Leaching-resistance Hydroxyacetone