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Age-specific mortality and fecundity of a spider mite under diet restriction and delayed mating

Insect Science 2022年第3期29卷 889-899页

作者： Guang-Yun Li zhi-qiang Zhang Centre for Biodiversity and Biosecurity School of Biological SciencesUniversity of AucklandAucklandNew Zealand Manaaki Whenua-Landcare Research AucklandNew Zealand Key Laboratory of Entomology and Pest Control Engineering College of Plant ProtectionSouthwest UniversityChongqingChina

Numerous experimental life-history studies on aging are mainly baised on two classical models—fruit fly Drosophila melanogaster(Meigen)and nematode Caenorhab-ditis elegans(Maupas)—with relatively little attention given to other organisms with different life-history ***-spotted spider mite Tetranychus urticae Koch(Acari:Tetranychidae)differs from many other arthropods in that the females continue their growth in the early adult stage and can reproduce sexually and *** this study,the influences of dietary restriction and delayed mating on the aging patterns of the spider mite were examined with the prevailing survival and reproduction trade-off hypothesis of aging being *** sex-specific responses of the spider mites were *** females showed longevity extension on diet restriction(fasting for 2 days in every 4 days)compared with their counterparts being fed ad libitum,and after delayed mating for 9 days,while the males displayed a decrease in lifespan when experiencing diet restriction but were not significantly influenced by delayed *** analysis was used to investigate the relationship between mite survival and reproduction traits,including longevity,female lifetime reproduction,age at first reproduction,early reproductive efforts and late reproductive efforts,yielding no evidence for trade-offs between these life-history *** additive effects of dietary restriction and delayed mating in lifespan extension of female spider mites were confirmed,proving that diet restriction is a robust anti-aging intervention,and that later onset of reproduction can prolong adult lifespan in females.

关键词： age-specific mortality delayed mating diet restriction reproduction sex difference trade-off

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On K_2-group of a Formal Matrix Ring

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Acta Mathematica Sinica,English Series 2012年第9期28卷 1897-1906页

作者： Zi qiang FAN zhi Xiang YIN Department of Mathematics Anhui University of Science and Technology

Let S be a formal matrix ring, T the subring consisting of all diagonal elements, I the set consisting of all off-diagonal elements. Then I is a split radical ideal under certain conditions. In this paper, we show tha... 详细信息

关键词： K2 group relative K2 group extension of groups

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Control of vortex-induced vibrations of the cylinder by using split-ter plates immersed in the cylinder wake at low Reynolds number

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Journal of Hydrodynamics 2020年第5期32卷 942-952页

作者： zhi-qiang Xin zhi-huang Wu Chui-jie Wu Dan Huang The College of Mechanics and Materials HoHai UniversityNanjing 211100China State Key Laboratory of Structural Analysis for Industrial Equipment and School of Aeronautics and Astronautics Dalian University of TechnologyDalianChina

The vortex-induced vibrations of a cylinder with two plates symmetrically distributed along the centerline of the wake are studied by using the fluid-structure interaction simulations on the Arbitrary Lagrangian-Eulerian *** this study,the different geo-metrical distribution parameters of the splitter plates and inflow velocities are taken into *** physical mechanisms of vortex-induced vibration of the cylinder with symmetrical plates are revealed from the cylinder amplitude,hydrodynamic force characteristics,vortex shedding frequency,and flow pattern *** results show that the dynamic interaction between the vortex shed from the oscillation cylinder and plates is responsible for the wake stabilization mechanism,and the stable wake and the dynamic response reduction of the main cylinder can be achieved at a wide range of reduced velocities by placing sym-metrical sheets at suitable locations.

关键词： Cylinder vortex-induced vibrations splitter plates vibration control flow pattern

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Analytical solution for stress and deformation of the mining floor based on integral transform

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International Journal of Mining Science and Technology 2015年第4期25卷 581-586页

作者： feng qiang Jiang Binsong State Key Laboratory of Geomechanics and Deep Underground Engineering China University of Mining & Technology Civil Engineering and Architecture Shandong Key Laboratory of Civil Engineering Disaster Prevention & Mitigation Shandong University of Science and Technology

Following exploitation of a coal seam, the final stress field is the sum of in situ stress field and an excavation stress field. Based on this feature, we firstly established a mechanics analytical model of the mining floor strata. Then the study applied Fourier integral transform to solve a biharmonic equation,obtaining the analytical solution of the stress and displacement of the mining floor. Additionally, this investigation used the Mohr–Coulomb yield criterion to determine the plastic failure depth of the floor strata. The calculation process showed that the plastic failure depth of the floor and floor heave are related to the mining width, burial depth and physical–mechanical properties. The results from an example show that the curve of the plastic failure depth of the mining floor is characterized by a funnel shape and the maximum failure depth generates in the middle of mining floor; and that the maximum and minimum principal stresses change distinctly in the shallow layer and tend to a fixed value with an increase in depth. Based on the displacement results, the maximum floor heave appears in the middle of the stope and its value is 0.107 m. This will provide a basis for floor control. Lastly, we have verified the analytical results using FLAC3 Dto simulate floor excavation and find that there is some deviation between the two results, but their overall tendency is consistent which illustrates that the analysis method can well solve the stress and displacement of the floor.

关键词： Integral transform Mining floor Plastic failure depth Floor heave Analytical solution

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Instability in Two-Sided Thermocapillary-Buoyancy Convection with Interfacial

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Chinese Physics Letters 2020年第1期37卷 19-23页

作者： Guo-feng Xu Qiu-Sheng Liu Jun Qin zhi-qiang Zhu Institute of Mechanics Chinese Academy of SciencesBeijing 100190 University of Chinese Academy of Sciences Beijing 100049

A new model of two-phase thermocapillary-buoyancy convection with phase change at gas-liquid interface in an enclosed cavity subjected to a horizontal temperature gradient is proposed,rather than the previous onesided model without phase *** study the onset of multicellular convection and two inodes of convective instability,and find four different flow *** transition map is compared with the non-phase-change *** numerical results show the stabilizing effect of interfacial phase change on the thermocapillarybuoyancy convection.

关键词： capillary thermocapillary phase

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Exact Convergence Rate of the Local Limit Theorem for a Branching Random Walk in Z^(d)with a Random Environment in Time

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Chinese Annals of Mathematics,Series B 2024年第5期45卷 805-822页

作者： Jian-xin LIU zhi-qiang GAO School of Mathematical Sciences Beijing Normal UniversityBeijing 100875China Laboratory of Mathematics and Complex Systems(Ministry of Education) School of Mathematical SciencesBeijing Normal UniversityBeijing 100875China

Consider a branching random walk with a random environment in time in the d-dimensional integer *** branching mechanism is governed by a supercritical branching process,and the particles perform a lazy random walk with an independent,non-identical increment *** A■Z^(d),let Z_(n)(A)be the number of offsprings of generation n located in *** exact convergence rate of the local limit theorem for the counting measure Z_(n)(·)is *** partially extends the previous results for a simple branching random walk derived by Gao(2017,*** Appl.).

关键词： Branching random walk Random environment Local limit theorems Exact convergence rate

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Extrusion process of 304L H-shaped stainless steel used in passive residual heat removal heat exchanger

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Nuclear Science and Techniques 2019年第4期30卷 70-79页

作者： Lei-feng Tuo Gen-Shu Zhou zhi-qiang Yu Xi-Tang Kang Bo-Wen Wang State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University Stainless Steel Tube Branch Company Taiyuan Iron & Steel Group CO.LTD Stainless Steel Tube Branch Company Taiyuan Iron & Steel (Group) CO.LTD

304L H-shaped stainless steel is used as the support frame of the passive residual heat removal heat exchanger(PRHR HX) in a nuclear fission reactor. The extrusion process is adopted to manufacture the 304L H-shaped stainless steel. Finite element method simulation is herein used to analyze metal flow characteristics, optimize the extrusion die, and predict the extrusion force at different temperatures and speeds. A Φ400-mm container and Φ388-mm forging billet are selected, and the 304L H-shaped stainless steel is successfully manufactured using a Germany SMS 60 MN horizontal extruder. The mechanical properties and microstructure of the manufactured 304L H-shaped stainless steel meet the requirements of the PRHR HX, and the surfaces of the product pass the dye penetration test. The H-shaped stainless steels are used in Haiyang nuclear power plant in Shandong Province.

关键词： PRHR HX Support frame Extrusion process 304L H-shaped stainless steel

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A curve-based material recognition method in MeV dual-energy X-ray imaging system

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Nuclear Science and Techniques 2016年第1期27卷 13-20页

作者： zhi-qiang Chen Tiao Zhao Liang Li Department of Engineering Physics Tsinghua University Key Laboratory of Particle and Radiation Imaging (TsinghuaUniversity) Ministry of Education

High-energy dual-energy X-ray digital radiography imaging is mainly used in the material recognition of cargo inspection. We introduce the development history and principle of the technology and describe the data process flow of our system. The system corrects original data to get a dual-energy transparence image. Material categories of all points in the image are identified by the classification curve,which is related to the X-ray energy spectrum. For the calibration of classification curve, our strategy involves a basic curve calibration and a real-time correction devoted to enhancing the classification accuracy. Image segmentation and denoising methods are applied to smooth the image. The image contains more information after colorization. Some results show that our methods achieve the desired effect.

关键词： X射线成像系统校准曲线材料识别识别方法数据处理流程透明图像分类精度实时校正

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Construction of complex digital rock physics based on full convolution network

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Petroleum Science 2022年第2期19卷 651-662页

作者： Jia Kang Nian-Yin Li Li-qiang Zhao Gang Xiong Dao-Cheng Wang Ying Xiong zhi-feng Luo State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Engineering Southwest Petroleum UniversityChengdu610500SichuanChina Research Institute of Natural Gas Technology Southwest Oil and Gas Field CompanyPetroChinaChengdu610213SichuanChina

Digital rock physics(DRP)is a paramount technology to improve the economic benefits of oil and gas fields,devise more scientific oil and gas field development plans,and create digital oil and gas ***,a significant gap is present between DRP theory and practical *** digital-core construction focuses only on simple cores,and the recognition and segmentation effect of fractures and pores of complex cores is *** identification of rock minerals is inaccurate,which leads to the difference between the digital and actual *** promote the application of DRP in developing oil and gas fields,based on the high-precision X-ray computed tomography scanning technology,the U-Net deep learning model of the full convolution neural network is used to segment the pores,fractures,and matrix from the complex rock core with natural fractures ***,the distribution of rock minerals is divided,and the distribution of rock conditions is corrected by X-ray diffraction.A pore—fracture network model is established based on the equivalent radius,which lays the foundation for fluid seepage ***,the accuracy of the established a digital core is verified by the porosity measured via nuclear magnetic resonance technology,which is of great significance to the development and application of DRP in oil and gas fields.

关键词： Digital rock physics Depth learning U-Net Complex core Complex fracture

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Review of borophene and its potential applications

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Frontiers of physics 2019年第3期14卷 65-84页

作者： zhi-qiang Wang Tie-Yu Lu Hui-Qiong Wang Yuan Ping feng Jin-Cheng Zheng Department of Physics and Collaborative Innovation Center for Optoelectronic Semiconductors and Efficient Devices Xiamen University Xiamen 361005 China Department of Physics National University of Singapore Singapore 117542 Singapore Institute of Artificial Intelligence Xiamen University Malaysia 439000 Sepang Selangor Malaysia Fujian Provincial Key Laboratory of Theoretical and Computational Chemistry Xiamen University Xiamen 361005 China

Since two-dimensional boron sheet (borophene) synthesized on Ag substrates in 2015, research on borophene has grown fast in the fields of condensed matter physics, chemistry, material science, and nanotechnology. Due to the unique physical and chemical properties, borophene has various potential applications. In this review, we summarize the progress on borophene with a particular emphasis on the recent advances. First, we introduce the phases of borophene by experimental synthesis and theoretical predictions. Then, the physical and chemical properties, such as mechanical, thermal, electronic, optical and superconducting properties are summarized. We also discuss in detail the utilization of the borophene for wide ranges of potential application among the alkali metal ion batteries, Li-S batteries, hydrogen storage, supercapacitor, sensor and catalytic in hydrogen evolution, oxygen reduction, oxygen evolution, and CO2 electroreduction reaction. Finally, the challenges and outlooks in this promising field are featured on the basis of its current development.

关键词： borophene structural diversity high anisotropy boron vacancy concentration

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