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Scattering-based hybrid network for facial attribute classification

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Frontiers of Computer Science 2024年第3期18卷 105-116页

作者： Na LIU fan zhang liang CHANG Fuqing DUAN School of Artificial Intelligence Beijing Normal UniversityBeijing 100875China

Face attribute classification(FAC)is a high-profile problem in biometric verification and face *** recent research has been devoted to extracting more delicate image attribute features and exploiting the inter-attribute correlations,significant challenges still *** scattering transform(WST)is a promising non-learned feature *** has been shown to yield more discriminative representations and outperforms the learned representations in certain *** to the image classification task,WST can enhance subtle image texture information and create local deformation *** paper designs a scattering-based hybrid block,to incorporate frequency-domain(WST)and image-domain features in a channel attention manner(Squeezeand-Excitation,SE),termed WS-SE *** with CNN,WS-SE achieves a more efficient FAC performance and compensates for the model sensitivity of the small-scale affine *** addition,to further exploit the relationships among the attribute labels,we propose a learning strategy from a causal *** cause attributes defined using the causalityrelated information can be utilized to infer the effect attributes with a high confidence *** analysis experiments demonstrate the effectiveness of our model,and our hybrid model obtains state-of-the-art results in two public datasets.

关键词： wavelet scattering transform causality-related learning facial attribute classification

Complete kinetic model for esterification reaction of lauric acid with glycerol to synthesize glycerol monolaurate

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Chinese Journal of Chemical Engineering 2024年第6期70卷 211-221页

作者： Han-Qiao Hu Yue zhang Ming fan Yong Cai Guang-Wen Chu liang-liang zhang Research Center of the Ministry of Education for High Gravity Engineering and Technology Beijing University of Chemical TechnologyBeijing 100029China State Key Laboratory of Organic-Inorganic Composites Beijing University of Chemical TechnologyBeijing 100029China Petrochemical Research Institute China National Petroleum CorporationBeijing 102206China

Glycerol monolaurate(GML)is a widely used industrial chemical with excellent emulsification and antibacterial *** direct esterification of glycerol with lauric acid is the main method to synthesize *** this work,the kinetic process of direct esterification was systematically studied using p-toluenesulfonic acid as catalyst.A complete kinetic model of consecutive esterification reaction has been established,and the kinetic equation of acid catalysis was *** isomerization reactions of GML and glycerol dilaurate were *** was found that the reaction was an equilibrium reaction and the reaction rate was faster than the esterification *** kinetic equations of the consecutive esterification reaction were obtained by experiments as k_(1)=(276+92261Xcat)exp(-37720/RT)and k_(2)=(80+4413Xcat)exp(-32240/RT).The kinetic results are beneficial to the optimization of operating conditions and reactor design in GML production process.

关键词： Glycerol monolaurate p-Toluenesulfonic acid Esterification Kinetics Mass transfer

Hybrid effect on mechanical properties and high-temperature performance of copper matrix composite reinforced with micro-nano dual-scale particles

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Journal of Materials Science & Technology 2024年第5期172卷 94-103页

作者： Xingde zhang Yihui Jiang Fei Cao Tian Yang fan Gao Shuhua liang School of Materials Science and Engineering Xi’an University of TechnologyXi’an 710048China Engineering Research Center of Conducting Materials and Composite Technology Ministry of EducationXi’an University of TechnologyXi’an 710048China Shaanxi Province Key Laboratory of Electrical Materials and Infiltration Technology Xi’an University of TechnologyXi’an 710048China

A dual-scale hybrid HfB_(2)/Cu-Hf composite with HfB_(2) microparticles and Cu_(5) Hf nanoprecipitates was designed and *** contribution of the hybrid effect to the mechanical properties and high-temperature performances was studied from macro and micro perspectives,*** hybrid of dual-scale particles can make the strain distribution of the composite at the early deformation stage more uniform and delay the strain concentration caused by the HfB_(2) *** dislocation pinning of HfB_(2) particles and the coherent strengthening of Cu_(5) Hf nanoprecipitates simultaneously play a strengthening role,but the strength of the hybrid composite is not a simple superposition of two strengthening *** addition,both Cu_(5) Hf nanoprecipitates and HfB_(2) microparticles contribute to the high-temperature performance of the composite,the growth and phase transition of nanoprecipitates at high temperature will reduce their contribution to strength,while the stable HfB_(2) particles can inhibit the coarsening of matrix grains and maintain the high-density geometrically necessary dislocations(GNDs)in the matrix,which ensures more excellent high-temperature resistance of the hybrid *** a result,the hy-brid structure can simultaneously possess the advantages of multiple reinforcements and make up for the shortcomings of each ***,a copper matrix composite with high strength,high conductivity,and excellent high-temperature performance is displayed.

关键词： Copper matrix composite HfB 2 particles Hybrid effect High strength and high conductivity High-temperature performance

Polycomb and trithorax:Their yin-yang dynamics in plants

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Molecular Plant 2024年第6期17卷 845-847页

作者： fan Xu Daolei zhang liang Le Li Pu Biotechnology Research Institute Chinese Academy of Agricultural SciencesBeijing 100081China School of Life Science Inner Mongolia UniversityHohhot 010021China

Polycomb(PcG)and trithorax(trxG)are two groups of conserved epigenetic complexes that maintain active and repressive states of target genes by altering their chromatin states to regulate plant development and stress *... 详细信息

关键词： maintain complexes states

Influence of Mixture Gas Conditions on the Laminar Combustion Characteristics of Natural Gas

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Journal of Thermal Science 2024年第3期33卷 1231-1241页

作者： LOU Diming ZHU Kan zhang Yunhua REN Yedi TAN Piqiang fanG liang fan Lanlan School of Automotive Studies Tongji UniversityShanghai201804China Ji’nan Power Co.Ltd Sinotruk GroupJi’nan250200China

Natural gas is a promising alternative fuel for the internal combustion engine,and natural gas engine has become an efficient and feasible measure to deal with the energy shortage and climate *** the laminar flame characteristics are the foundation of the turbulent flame,the laminar flame characteristics of natural gas have a significant impact on the combustion status and efficiency of the engine.A visual constant volume bomb was used to study the influence of the gas components,different excess air coefficient(λ),and initial conditions on the laminar combustion characteristics of natural *** experimental results showed that when the initial pressure and temperature were 0.1 MPa and 300 K respectively,compared to propane,ethane had a remarkable influence on the equivalent-combustion laminar-combustion-speed,with an average increase of approximately 5.1%for every 2.5%increase in the ethane *** laminar combustion velocity of the natural gas under different excess air coefficients had a maximum value at aboutλ=1.0,and the Markstein length of the flame decreased with the increase of theλ.The increase in the initial pressure of the mixture resulted in a decrease in the equivalent-combustion laminar-combustion-speed of the flame,a significant decrease in the Markstein *** increase of the initial temperature of the mixture led to a rapid increase of the equivalent-combustion laminar-combustion-speed,but the effect on the flame Markstein length was not dominant.

关键词： constant volume bomb natural gas engine combustion characteristics laminar combustion velocity Markstein length

Mechanism of high Li-ion conductivity in poly(vinylene carbonate)-poly(ethylene oxide)cross-linked network based electrolyte revealed by solid-state NMR

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Journal of Energy Chemistry 2024年第6期93卷 377-383,I0010页

作者： fan Li Tiantian Dong Yi Ji Lixin liang Kuizhi Chen Huanrui zhang Guanglei Cui Guangjin Hou State Key Laboratory of Catalysis Dalian National Laboratory for Clean EnergyCollaborative Innovation Center of Chemistry for Energy MaterialsDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing 100049China Qingdao Industrial Energy Storage Research Institute Qingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of SciencesQingdao 266101ShandongChina

Solid polymer electrolytes(SPEs)have become increasingly important in advanced lithium-ion batteries(LIBs)due to their improved safety and mechanical properties compared to organic liquid ***-linked polymers have the potential to further improve the mechanical property without trading off Li-ion *** this study,focusing on a recently developed cross-linked SPE,i.e.,the one based on poly(vinylene carbonate)-poly(ethylene oxide)cross-linked network(PVCN),we used solid-state nuclear magnetic resonance(NMR)techniques to investigate the fundamental interaction between the chain segments and Li ions,as well as the lithium-ion *** utilizing homonuclear/heteronuclear correlation,CP(cross-polarization)kinetics,and spin-lattice relaxation experiments,etc.,we revealed the structural characteristics and their relations to lithium-ion *** is found that the network formation prevents poly(ethylene oxide)chains from crystallization,which could create sufficient space for segmental tumbling and Li-ion co nductio *** such,the mechanical property is greatly improved with even higher Li-ion mobilities compared to the poly(vinylene carbonate)or poly(ethylene oxide)based SPE analogues.

关键词： ssNMR Lithium-ion mobility Cross-link Solid polymer electrolyte

Analysis and experimental study on resistance-increasing behavior of composite high efficiency autonomous inflow control device

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Petroleum Science 2024年第2期21卷 1290-1304页

作者： liang-liang Dong Yu-Lin zhang School of Mechatronic Engineering Southwest Petroleum UniversityChengdu610500SichuanChina State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Southwest Petroleum UniversityChengdu610500SichuanChina Oil and Gas Equipment Technology Sharing and Service Platform of Sichuan ProvinceChengdu610500SichuanChina

Bottom water coning is the main reason to reduce the recovery of horizontal bottom water reservoir. By water coning, we mean the oil-water interface changes from a horizontal state to a mound-shaped cone and breaks through to the wellbore. Autonomous inflow control device(AICD) is an important instrument maintain normal production after bottom water coning, however, the resistance increasing ability of the swirl type AICD is insufficient at present, which seriously affects the water control effect. Aiming this problem, this paper designs a multi-stage resistance-increasing and composite type AICD. The separation mechanism of oil-water two phases in this structure, the resistance form of oil-water single phase and the resistance-increasing principle of water phase are analyzed. Establishing the dual-phase multi-stage separation and resistance-increasing model, and verified by measuring the throttling pressure drop and oil-water volume fraction of the AICD, it is found that the composite type AICD has the effect of ICD and AICD at the same time, which can balance the production rate of each well section at the initial stage of production, delay the occurrence of bottom water coning. In the middle and later stages of production, water-blocking can be effectively increased to achieve water control and stable *** structural sensitivity analysis, the influence law of various structural parameters on the water control performance of composite AICD was obtained. The simulation calculation results show that,compared with the existing swirl type AICD, composite AICD has higher sensitivity to moisture content,the water phase throttling pressure drop is increased by 4.5 times on average. The composite AICD is suitable for the entire stage of horizontal well production.

关键词： Water control Flow separation Flow resistance-increasing AICD device Simulation and experiment

Soliton resolution and asymptotic stability of N-solutions for the defocusing Kundu–Eckhaus equation with nonzero boundary conditions

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Communications in Theoretical Physics 2024年第1期76卷 1-6页

作者： Engui fan Yanxi zhang School of Mathematical Sciences and Key Laboratory of Mathematics for Nonlinear Science Fudan UniversityShanghai200433China Tianjin Xinhua High School No.99 machang RoadTianjin300204China

In this paper,we address interesting soliton resolution,asymptotic stability of N-soliton solutions and the Painleve asymptotics for the Kundu-Eckhaus(KE)equation with nonzero boundary conditions iq_(t)+q_(xx)-2(l|q|^(2)-1)q+4β^(2)(lql^(4)-1)q+4iβ(lql^(2))_(x)q=0,q(x,0)=q_(0)(x)-±1,x→±∞.The key to proving these results is to establish the formulation of a Riemann-Hilbert(RH)problem associated with the above Cauchy problem and find its connection with the RH problem of the defocusing NLS *** the■-steepest descent method and the results of the defocusing NLS equation,we find complete leading order approximation formulas for the defocusing KE equation on the whole(x,t)half-plane including soliton resolution and asymptotic stability of N-soliton solutions in a solitonic region,Zakharov-Shabat asymptotics in a solitonless region and the Painlevéasymptotics in two transition regions.

关键词： defocusing Kundu-Eckhaus equation Riemann-Hilbert problems steepest descent method soliton resolution asymptotic stability Painleve transcendents

Multistimuli-Responsive Luminescent Porous Organic Polymers with Chiroptical Properties and Acid-Induced Degradation

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Chinese Journal of Chemistry 2024年第16期42卷 1886-1894页

作者： Youling He Dongyang fan liang zhang Dong Wang Ting Han Rongrong Hu Ben Zhong Tang Center for AIE Research Shenzhen Key Laboratory of Polymer Science and TechnologyGuangdong Research Center for Interfacial Engineering of Functional MaterialsCollege of Materials Science and EngineeringShenzhen UniversityShenzhenGuangdong 518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhenGuangdong 518060China Department of Chemistry Hong Kong Branch of Chinese National Engineering Research Center for Tissue Restoration and ReconstructionThe Hong Kong University of Science and TechnologyClear Water BayKowloonHong Kong999077China State Key Laboratory of Luminescent Materials and Devices Guangdong Provincial Key Laboratory of Luminescence from Molecular AggregatesSouth China Universityof TechnologyGuangzhouGuangdong 510640China School of Science and Engineering Shenzhen Institute of Aggregate Science and TechnologyThe Chinese University of Hong KongShenzhen(CUHK-Shenzhen)Guangdong 518172China

Porous organic polymers(POPs)have attracted great attention in past *** diverse functional POPs have been developed,multistimuli-responsive POPs with excellent aggregate-state luminescence together with good chiroptical properties have rarely been ***,two pairs of Salen-type enantiomeric PoPs with multistimuli-responsive luminescence and chiral features were designed and synthesized by facile polycondensation reactions between polyfunctional aggregation-induced emission luminogen(AlEgen)-containing salicylaldehyde derivatives and chiral *** Salen units in polymer backbones as tetradentate ligands,a series of POP-metal complexes were further *** obtained POPs and metal complexes show good porosity,high thermal stability,and obvious circular dichroism ***,benefiting from the coexistence of AlEgen and Salen units in polymer structures,these POPs exhibit excellent luminescence performance in aggregate states and tunable fluorescence behaviors in response to external stimuli of Zn^(2+)ion,mechanical forces,organic solvent,and *** to the dynamic feature of Schiff base C=N bonds,the present POPs can efficiently undergo hydrolysis reactions under strong acidic conditions to reproduce the AlEgencontaining monomers,and such an acid-induced degradation process can be directly visualized and dynamically monitored via fluorescence *** properties collectively make the POPs candidate materials for applications in heterogeneous asymmetric catalysis,fluorescence sensing,biomedicine,etc.

关键词： Polymers Stimuli-responsive luminescence Porous polymers Chirality Aggregation-induced emission Fluorescence Schiff bases Degradation