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A two-phase fluid model for epidemic flow

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Infectious Disease Modelling 2023年第3期8卷 920-938页

作者： ziqiang cheng Jin Wang School of Mathematics Hefei University of TechnologyHefeiAnhui230009China Department of Mathematics University of Tennessee at ChattanoogaChattanoogaTN37403USA

We propose a new mathematical and computational modeling framework that in-corporates fluid dynamics to study the spatial spread of infectious *** model the susceptible and infected populations as two inviscid fluids which interact with each *** motion at the macroscopic level characterizes the progression and spread of the *** implement the two-phase flow model,we employ high-order numerical methods from computational fluid *** apply this model to simulate the COVID-19 outbreaks in the city of Wuhan in China and the state of Tennessee in the *** modeling and simulation framework allows us to conduct a detailed investigation into the complex spatiotemporal dynamics related to the transmission and spread of COVID-19.

关键词： Epidemic spread Fluid dynamics COVID-19 simulation

Numerical simulation of a complex moving rigid body under the impingement of a shock wave in 3D

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Advances in Aerodynamics 2022年第1期4卷 147-175页

作者： Shihao Liu ziqiang cheng Yan Jiang Jianfang Lu Mengping Zhang Shuhai Zhang School of Mathematical Sciences University of Science and Technology of ChinaHefei230026AnhuiChina School of Mathematics Hefei University of TechnologyHefei230000AnhuiChina School of Mathematics South China University of TechnologyGuangzhou510641GuangdongChina State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang621000SichuanChina

In this paper,we take a numerical simulation of a complex moving rigid body under the impingement of a shock wave in three-dimensional *** compressible inviscid fluid and viscous fluid are considered with suitable boundary *** develop a high order numerical boundary treatment for the complex moving geometries based on finite difference methods on fixed Cartesian *** method is an extension of the inverse Lax-Wendroff(ILW)procedure in our works(cheng et al.,Appl Math Mech(Engl Ed)42:841-854,2021;Liu et al.)for 2D *** from the 2D case,the local coordinate rotation in 3D required in the ILW procedure is not *** give a theoretical analysis to show that the boundary treatment is independent of the choice of the rotation,ensuring the method is feasible and *** translation and rotation of the body are taken into account in this *** particular,we reformulate the material derivative for inviscid fluid on the moving boundary with no-penetration condition,which plays a key role in the proposed *** simulations on the cylinder and sphere are given,demonstrating the good performance of our numerical boundary treatments.

关键词： Inverse Lax-Wendroff procedure High order accuracy Complex moving boundary treatment Compressible inviscid fluid Compressible viscous fluid 3D

Facing small and biased data dilemma in drug discovery with enhanced federated learning approaches

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Science China(Life Sciences) 2022年第3期65卷 529-539页

作者： Zhaoping Xiong ziqiang cheng Xinyuan Lin Chi Xu Xiaohong Liu Dingyan Wang Xiaomin Luo Yong Zhang Hualiang Jiang Nan Qiao Mingyue Zheng Shanghai Institute for Advanced Immunochemical Studies and School of Life Science and TechnologyShanghaiTech UniversityShanghai 200031China Drug Discovery and Design Center State Key Laboratory of Drug ResearchShanghai Institute of Materia MedicaChinese Academy of SciencesShanghai 201203China University of Chinese Academy of Sciences Beijing 100049China School of Information Science and Technology University of Science and Technology of ChinaHefei 230000China Laboratory of Health Intelligence Huawei Technologies Co.LtdShenzhen 518100China

Artificial intelligence(AI)models usually require large amounts of high-quality training data,which is in striking contrast to the situation of small and biased data faced by current drug discovery *** concept of federated learning has been proposed to utilize distributed data from different sources without leaking sensitive information of the *** emerging decentralized machine learning paradigm is expected to dramatically improve the success rate of AI-powered drug ***,we simulated the federated learning process with different property and activity datasets from different sources,among which overlapping molecules with high or low biases exist in the recorded *** the benefit of gaining more data,we also demonstrated that federated training has a regularization effect superior to centralized training on the pooled datasets with high ***,different network architectures for clients and aggregation algorithms for coordinators have been compared on the performance of federated learning,where personalized federated learning shows promising *** work demonstrates the applicability of federated learning in predicting drug-related properties and highlights its promising role in addressing the small and biased data dilemma in drug discovery.

关键词： federated learning drug discovery Fed AMP Non-IID data

Enhanced N_(2)-to-NH_(3)conversion efficiency on Cu3P nanoribbon electrocatalyst

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Nano Research 2022年第8期15卷 7134-7138页

作者： Qian Liu Yiting Lin Shuang Gu ziqiang cheng Lisi Xie Shengjun Sun Longcheng Zhang Yongsong Luo Abdulmohsen Ali Alshehri Mohamed SHamdy Qingquan Kong Jiahong Wang Xuping Sun Institute for Advanced Study Chengdu UniversityChengdu 610106China Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China Shenzhen Engineering Center for the Fabrication of Two-Dimensional Atomic Crystals Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China Chemistry Department Faculty of Science&Center of Excellence for Advanced Materials ResearchKing Abdulaziz UniversityP.O.Box 80203Jeddah 21589Saudi Arabia Catalysis Research Group(CRG) Department of ChemistryCollege of ScienceKing Khalid UniversityP.O.Box 9004Abha 61413Saudi Arabia

Ambient electroreduction of nitrogen(N_(2))is considered as a green and feasible approach for ammonia(NH_(3))synthesis,which urgently demands for efficient *** has close relationship with catalytic activity of heterogeneous *** is attractive nanostructure,which possesses the flexibility of one-dimensional nanomaterials,the large surface area of two-dimensional nanomaterials,and lateral size confinement *** this work,Cu_(3)P nanoribbon is proposed as a highly efficient electrocatalyst for N_(2)-to-NH_(3)conversion under benign *** measured in N_(2)-saturated 0.1 M HCl,such Cu_(3)P nanoribbon achieves high performance with an excellent Faradaic efficiency as high as 37.8%and a large yield of 18.9μg·h^(−1)·mgcat.−1 at−0.2 *** also demonstrates outstanding stability in long-term electrolysis test at least for 45 h.

关键词： Cu_(3)P nanoribbon nitrogen reduction reaction ammonia electrosynthesis electrocatalysis

A high order boundary scheme to simulate complex moving rigid body under impingement of shock wave

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Applied Mathematics and Mechanics(English Edition) 2021年第6期42卷 841-854页

作者： ziqiang cheng Shibao LIU Yan JIANG Jianfang LU Mengping ZHANG Shuhai ZHANG School of Mathematical Sciences University of Science and Technology of ChinaHefei 230026China South China Research Center for Applied Mathematics and Interdisciplinary Studies South China Normal UniversityGuangzhou 510631Chins State Key Laboratory of Aerodynamics China Aerodynamics Research and Development CenterMianyang 621000Sichuan ProvinceChina

In the paper, we study a high order numerical boundary scheme for solving the complex moving boundary problem on a fixed Cartesian mesh, and numerically investigate the moving rigid body with the complex boundary under the impingement of an inviscid shock wave. Based on the high order inverse Lax-Wendroff(ILW) procedure developed in the previous work(TAN, S. and SHU, C. W. A high order moving boundary treatment for compressible inviscid flows. Journal of Computational Physics, 230(15),6023–6036(2011)), in which the authors only considered the translation of the rigid body,we consider both translation and rotation of the body in this paper. In particular, we reformulate the material derivative on the moving boundary with no-penetration condition, and the newly obtained formula plays a key role in the proposed algorithm. Several numerical examples, including cylinder, elliptic cylinder, and NACA0012 airfoil, are given to indicate the effectiveness and robustness of the present method.

关键词： inverse Lax-Wendroff(ILW)procedure complex moving boundary scheme Cartesian mesh high order accuracy compressible inviscid shock wave

Congruences on Orthodox Semirings Whose Additive Idempotents Satisfy Permutation Identities

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Journal of Mathematical Research with Applications 2013年第5期33卷 569-577页

作者： Shiju PAN Yuanlan ZHOU ziqiang cheng Department of Mathematics Jiangxi Normal University

The investigation of congruences on generalized inverse semigroups is *** some properties of such semigroups,the congruences on an orthodox semiring whose idempotents satisfy permutation identities are *** addition,we... 详细信息

关键词： inverse semiring congruence band semiring.

High-Temperature Synthesis in Nonpolar Solvent for CsPbBr3 and CH3NH_3PbBr3 Perovskite Nanocrystals with High-Efficient Luminescence

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Wuhan University Journal of Natural Sciences 2017年第5期22卷 429-434页

作者： LIU Xiaodan WANG Qiang cheng ziqiang ZHOU Li WANG Ququan Key Laboratory of Artificial Micro-and Nano-structures ofthe Ministry of Education School of Physics and TechnologyWuhan UniversityWuhan 430072HubeiChina

We report a method to synthesize both organicinorganic CH3NH3PbBr3 and all-inorganic CsPbBr3 perovskite nanocrystals in nonpolar solvent at high temperature. The cesium oleate and CH3NH3Br （MABr） are prepared and then injected into the nonpolar solvent of octadecene including oleic acid, oleylamine, and lead halide. In the synthesis of organic-inorganic perovskites of CHaNH3PbBr3, the frequently-used polar solvent of dimetbylformamide or other polar solvents are not used. The prepared CsPbBr3 nanocrystals are spherical nanoparticles with the diameter of 250 nm. The CHaNH3PbBr3 perovskites are micro-scale hexagonal nanoplatelets. The colloidal perovskites exhibit high-efficient fluorescence and excellent stability.

关键词： perovskite nanocrystals luminescence nonpolar solvent

Asymmetric growth of Au-core/Ag-shell nanorods with a strong octupolar plasmon resonance and an efficient second-harmonic generation

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Nano Research 2018年第2期11卷 686-695页

作者： Sijing Ding Dajie Yang Xiaoli Liu Fan Nan ziqiang cheng Song-Jin Im Li Zhou Jianfang Wang Ququan Wang Department of Physics Key Laboratory of Artificial Micro- and Nano-structures of the Ministry of Education Wuhan University Wuhan China Department of Physics The Chinese University of Hong Kong Shatin Hong Kong China The Institute for Advanced Studies Wuhan University Wuhan China Department of Physics Qufu Normal University Qufu China Department of Physics Kim Il Sung University Pyongyang Democratic People’s Republic of Korea

Colloidal Au-core/Ag-shell nanorods with an asymmetric transverse cross- section and a strong octupolar plasmon resonance are synthesized by the controlled growth of Ag shells on one side of the Au cores. A largely enhanced second harmonic generation （SHG） from these asymmetric core-shell nanorods is demonstrated for the first time by tuning the dipolar and the octupolar plasmon modes to make them resonant with the fundamental and harmonic frequencies, respectively. The SHG intensity of the Au-Ag nanorods with dual-frequency resonances is enhanced by 21 times compared to that of the bare Au nanorods. The co-existence of the dipolar, quadrupolar, and octupolar radiations in the SHG is revealed. Additionally, the cellular uptake of the Au-Ag nanorods is monitored and the evolution of the membrane bleb is successfully observed by the SHG imaging. Our observations provide a strategy for enhancing the SHG of the colloidal metal nanoparticles and can have applications in chemical process monitoring and biological sensing.

关键词： gold-core/silver-shellnanorods asymmetric growth octupole surface plasmonresonance second-harmonic generation

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家禽血管瘤的发生与防制

中国家禽 2009年第18期31卷 1-4,10页

作者：成子强山东农业大学动物科技学院山东泰安271018

近几年来,与J亚群白血病病毒相关的禽白血病在我国禽群中广泛流行,其中,与禽白血病J亚群病毒(ALV-J)密切相关的血管瘤性疾病在我国蛋鸡群中呈蔓延趋势。本文就血管瘤的病原及发病机理、流行病学、临床症状、病理变化及防制的相关知识作... 详细信息

近几年来,与J亚群白血病病毒相关的禽白血病在我国禽群中广泛流行,其中,与禽白血病J亚群病毒(ALV-J)密切相关的血管瘤性疾病在我国蛋鸡群中呈蔓延趋势。本文就血管瘤的病原及发病机理、流行病学、临床症状、病理变化及防制的相关知识作一系统介绍。

关键词：血管瘤禽白血病病毒J亚群(ALV-j) 发生防制