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Animal influenza virus

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Journal of Integrative Agriculture 2019年第7期18卷 1419-1420页

作者： chen hua-lan Harbin Veterinary Research Institute Chinese Academy of Agricultural Sciences

Animal influenza viruses continuously circulate in their reservoirs in nature and pose severe threat to humans and animals;therefore,understanding and control of animal influenza viruses will have important implicatio... 详细信息

关键词： viruses reservoirs public health

Knowledge Graph Representation Learning Based on Automatic Network Search for Link Prediction

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Computer Modeling in Engineering & Sciences 2023年第6期135卷 2497-2514页

作者： Zefeng Gu hua chen China University of Petroleum(East China) Qingdao266555China

Link prediction,also known as Knowledge Graph Completion(KGC),is the common task in Knowledge Graphs(KGs)to predict missing connections between *** existing methods focus on designing shallow,scalable models,which have less expressive than deep,multi-layer ***,most operations like addition,matrix multiplications or factorization are handcrafted based on a few known relation patterns in several wellknown datasets,such as FB15k,WN18,***,due to the diversity and complex nature of real-world data distribution,it is inherently difficult to preset all latent *** address this issue,we proposeKGE-ANS,a novel knowledge graph embedding framework for general link prediction tasks using automatic network *** can learn a deep,multi-layer effective architecture to adapt to different datasets through neural architecture *** addition,the general search spacewe designed is tailored *** performextensive experiments on benchmark datasets and the dataset constructed in this *** results show that our KGE-ANS outperforms several state-of-the-art methods,especially on these datasets with complex relation patterns.

关键词： Knowledge graph embedding link prediction automatic network search

Synthesis and Crystal Structure of 1-(N,N-Di-(p-toluenesulfonyl))-amino-2-(N'-p-toluenesulfonyl)-amino-3,5-dinitrobenzene

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Chinese Journal of Structural Chemistry 2007年第3期26卷 309-313页

作者： chen hua-Mei LIN Hai LIN hua-Kuan Department of Chemistry Nankai University Tianjin 300071 China State Key Laboratory of Functional Polymer Materials for Absorption and Separation Nankai University Tianjin 300071 China

The title compound, 1-（N,N-di-（p-toluenesulfonyl））-amino-2-（N＇-p-toluenesulfonyl）- amino-3,5-dinitrobenzene, was synthesized and structurally determined by single-crystal X-ray diffraction method. It crystallizes in orthorhombic, space group Pna21 with a = 13.723（2）, b = 25.354（4）, c = 8.6565（12） A, V= 3011.9（8） A^3, Z = 4, Mr = 660.68, F（000） = 1368, Dc = 1.457 g/cm^3, μ = 0.309, the final R = 0.0609 and wR = 0.1042. The H atom of N2-H group, which is the unique recognition site to anion, is enveloped by two oxygen atoms and one benzene from two and one p-toluenesulfonyl moieties, respectively.

关键词： sulfonylamide anion recognition receptor crystal structure

Fractional-order Generalized Principle of Self-support (FOGPSS) in Control System Design

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IEEE/CAA Journal of Automatica Sinica 2016年第4期3卷 430-441页

作者： hua chen YangQuan chen Mathematics and Physics Department Hohai University MESA Laboratory University of California

This paper reviews research that studies the principle of self-support U+0028 PSS U+0029 in some control systems and proposes a fractional-order generalized PSS framework for the first time. The existing PSS approach focuses on practical tracking problem of integer-order systems including robotic dynamics, high precision linear motor system, multi-axis high precision positioning system with unmeasurable variables, imprecise sensor information, uncertain parameters and external disturbances. More generally, by formulating the fractional PSS concept as a new generalized framework, we will focus on the possible fields of the fractional-order control problems such as practical tracking, U+03BB-tracking, etc. of robot systems, multiple mobile agents, discrete dynamical systems, time delay systems and other uncertain nonlinear systems. Finally, the practical tracking of a first-order uncertain model of automobile is considered as a simple example to demonstrate the efficiency of the fractional-order generalized principle of self-support U+0028 FOGPSS U+0029 control strategy. © 2014 Chinese Association of Automation.

关键词： Control systems Delay control systems Dynamical systems Linear motors Mobile agents Robotics Time delay Uncertainty analysis

Hot ductility behavior of V-N and V-Nb microalloyed steels

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International Journal of Minerals,Metallurgy and Materials 2012年第6期19卷 525-529页

作者： Bing-hua chen Hao Yu School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

The hot ductility of V-N and V-Nb microalloyed steels was investigated on a Gleeble-1500 thermomechanical simulator, and the results were compared with those of V and Nb microalloyed steels. A ductility trough is found in both the steels in the temperature range of 700 to 1050℃. Compared to the V steel, the V-N steel has a wider and deeper ductility trough with the increase of N content, due to the in- creased precipitation of V（C, N） in the steel. Above 930℃, when 0.047wt% V is added to the 0.028wt% Nb-containing steel, the ductility becomes worse, owing to the rise of the onset dynamic recrystallization temperature. However, the ductility gets better at 800 to 930℃ be- cause of the coarsening of precipitates in austenite. With the improvement in ductility, the fracture mechanism is changed from intergranular to high ductile fracture in the temperature range of 800 to 1050℃.

关键词： alloy steel ductility dynamic recrystallization precipitation

Electronic structure and properties of FeS_2 with the space groups of Pa3 and P1

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International Journal of Minerals,Metallurgy and Materials 2013年第7期20卷 671-677页

作者： Cui-hua Zhao Bo-zeng Wu Jian-hua chen Yu-qiong Li Ye chen School of Chemistry and Chemical Engineering Guangxi University China Tin Group Co. Ltd. College of Material Science and Engineering Guangxi University College of Resources and Metallurgy Guangxi University

The electronic structure and properties of FeS2 with the space groups of Pa3 and P1 were studied by the density functional theory. The generalized-gradient approximation exchange-correlation functional was used in conjunction with a plane wave-ultrasoft pseudopotential representation. Calculation results show that differences are observed in electronic structures and properties between Pa3 and P1 crystals. The band gap and energy loss of P1 are smaller than those of Pa3 crystal, while the dielectric constant, conductivity, refractive index, extinction coefficient, and intensity of optical absorption of P1 are larger than those of Pa3. These behaviors are attributed to the differences in symmetry, atomic arrangement, and Mulliken bond population of each unit for Pa3 and P1 crystals.

关键词： pyrites electronic structure optical properties crystal structure density functional theory

Preparation of PVA/GO/h-BN Janus Film with High Thermal Conductivity and Excellent Flexibility via a Density Deposition Self-assembly Method

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Chinese Journal of Polymer Science 2024年第8期42卷 1217-1226页

作者： Fang-hua Luo Zhi-Tao Dong Guo-hua chen chen Ma huai-Yuan Wang College of Chemistry and Chemical Engineering Northeast Petroleum UniversityDaqing 163318China College of Materials Science and Engineering Huaqiao UniversityXiamen 361000China School of Chemical Engineering and Technology and State Key Laboratory for Chemical Engineering Tianjin UniversityTianjin 300350China

Janus films with asymmetric physical/chemical properties have attracted con siderable attention due to their promising applications in personal thermal management,electronic skin s,sensors,actuators,***,traditional methods for fabricating Janus films conventionally need the assistance of an interface or auxiliary equipment,which are usually complex and ***,flexible poly(vinyl alcohol)(PVA)/graphene oxide(GO)/h-BN(recorded as PVA/GO/h-BN)Janus films with thermally,optically,and electrically anisotropic properties are fabricated by a simple density deposition self-assem bly method,which just utilizes the density difference between GO and h-BN during water *** results show that the two sides of the acquired Janus films have obvious asymmetric *** the original state of the PVA/GO/h-BN Janus films,the thermal conductivity of the GO side(10.06 W·m^(-1)·K^(-1))is generally lower than that of the h-BN side(10.48W·m^(-1)·K^(-1)).But after GO is reduced,the thermal conductivity of the rGO side reaches 12.17 W·m^(-1)·K^(-1),surpassing that of the h-BN *** addition,the relative reflectance of the h-BN side of Janus film is also significantly higher than that of the rGO side,and the su rface resistance difference between the two sides is about 4 orders of *** prepared PVA/GO/h-BN Janus films show great application potential in human thermal management,light conversion switches,and electronic *** study provides a simple and versatile strategy for fabricating Janus films with multifunctional(such as thermal,optical,and electrical)anisotropies.

关键词： Janus films PVA/GO/h-BN Density deposition self-assembly method

Predictions of γ(4S)→h_b(1P,2P)π^+π^- transitions

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Chinese Physics C 2020年第2期44卷 42-50页

作者： Yun-hua chen School of Mathematics and Physics University of Science and Technology BeijingBeijing 100083China

We study the contributions of intermediate bottomonium-like Zb states and the bottom meson loops in the heavy quark spin flip transitionsγ(4 S)→hb(1 P,2 P)π+π-.Depending on the constructive or destructive interferences between the Zb-exchange and the bottom meson loops mechanisms,we predict two possible branching ratios for each process:BRγ(4 S)→hb(1 P)π+π-≈(1.***.40.8×10^-6)or(0.5-0.20.5×10^-6),and BRγ(4 S)→(2 P)π+π-≈(7.1-1.1+1.7×10^-10)or(2.4-0.10.2×10^-10)).The contribution of the bottom meson loops is found to be considerably larger than that of the Zbexchange in the T(4 S)→hb(1 P)ππtransitions,while its decay rates are not comparable to those of heavy quark spin conservedγ(4 S)→γ(1 S,2 S)ππ*** also predict the contribution of the charm meson loops in the branch fractions ofΨ(3 S,4 S)→hc(1 P)ππ.

关键词： quarkonium exotic states nonrelativistic effective field theory

Research in non-equalization machining method for spatial cam

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第9期9卷 1258-1263页

作者： Jun-hua chen Yi-jie WU Institute of Mechanical and Electrical Engineering Ningbo Institute of Technology Zhefiang University Ningbo 315010 China Institute of Modern Manufacture Engineering Zhejiang University Hangzhou 310027 China

Many kinds of devices with cam have been widely used in various mechanical equipments. However, non-equalization machining for spatial cam trough remains to be a difficult problem. This paper focuses on the analysis of running conditions and machining processes of spatial cam with oscillating follower. We point out the common errors in the biased distance cutting. By analyzing the motion of oscillating follower of spatial cam, we present a new 3D curve expansion model of spatial cam trough-outline. Based on this model, we have proposed a machining method for trochoidal milling with non-equalization diameter cutter. This new method has led to a creative and effective way for non-equalization diameter machining for spatial cam with oscillating follower.

关键词： Oscillating follower Spatial cam 3D curve exoansion Trochoidal milling Non-eaualization diameter