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internal Tide Generation and Dissipation by Small Periodic Topography in Deep Ocean

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Journal of Ocean University of China 2019年第4期18卷 761-770页

作者： LI Qiang MAO Xianzhong DENG Guotong ZHAO Ruixiang ZHANG Chuanzheng ZHU Xiaohua Graduate School at Shenzhen Tsinghua University Shenzhen 518055 China State Key Laboratory of Satellite Ocean Environment Dynamics Second Institute of Oceanography Ministry of Natural Resources Hangzhou 310012 China

internal tides generated by a rough sea floor are an important source of mixing in the abyssal ocean. Two linear models are employed to evaluate the conversion rate from barotropic tides to internal tides and the energy distribution in each mode. Considering the periodicity of internal tides, the topography is represented by periodically distributed knife edges and sinusoidal ridges within one wavelength of mode-1 internal tides. The knife edges generate greater internal tides than the sinusoidal ridges due to their sharp shape, which approximates an extremely supercritical condition. Energy flux concentrates in modes whose numbers are multiples of the knife edge or ridge number. Then, a fully nonlinear model that integrates viscosity and diffusion is implemented, and its results are compared with those of the linear model. internal wave rays generated in the nonlinear model show a distribution similar to the linear models’ prediction. High dissipation rates coincide with the rays, suggesting that nonlinear wave-wave interaction is a domi- nant mechanism for internal tide dissipation in the abyssal ocean.

关键词： internal wave generation multiple ridges normal modes conversion rate dissipation

internal crack recovery of 20MnMo steel

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Science China(Technological Sciences) 1997年第2期40卷 164-169页

作者：韩静涛赵钢曹起骧 Department of Metalforming University of Science and Technology Beijing Beijing 100083 The 1202 Factory of PLA Beijing 100081 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

According to the results of physical modelling, SEM and SAM analysis of 20MnMo steel samples, internal cracks of metal parts are recoverable. The motive power of the recovery is atom diffusion and migration from matrix to voids. The recovery process consists of two steps. In the first step, the void area is filled up with a kind of metal mass, beginning from the crack tip. There are many microvoids in the mass with different microstructure from the matrix. In the second step, microvoids decrease in size and number, and the mass microstructure approaches the matrix, with the heating temperature increasing and the holding time prolonging. Recovery tests on rejected heavy forgings are successfully processed. It is believed that the recovery technique is a potential method for improving the internal quality and reducing the production loss and cost of metal products. Similar method can be used to treat other metal construction parts for rescuing them or prolonging their service life. Further research and

关键词： internal crack crack recovery forging SEM SAM.

An internal-variable theory of thermo-viscoelastic constitutive relations at finite strain

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Science China Mathematics 2000年第5期43卷 545-551页

作者：黄筑平陈建康王文标 Department of Mechanics and Engineering Sciences Peking University Beijing 100871 China Division of Physics Graduate School at Beijing USTC Beijing 100039 China

Based on the nonequilibrium thermodynamic theory, a new thermo-viscoelastic relation at finite strain is proposed. Under the assumption that the specific heat at a fixed strain and fixed internal variables can be regarded as a constant, a new expression for the free energy which decouples the mechanical and the thermal effects is derived. Through an analysis of the mesoscopic deformation mechanism of solid polymers, a set of internal variables is introduced, and an internal-variable consti-tutive theory in thermo-viscoelasticity at finite strain is formulated. An explicit expression of a thermo-viscoelastic constitutive relation is obtained for solid polymers in the case where their molecular network has a randomly oriented distribution function at reference configuration. Moreover, the relationship be-tween the relaxation time and the temperature is also discussed. The viscoelastic constitutive theory proposed in reference is only a linear approximation of the present theory.

关键词： thermo-viscoelasticity internal variables flnite strain.

internal Waves Generated by Tidal Flows over a Triangular Ridge with Critical Slopes

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Journal of Ocean University of China 2019年第5期18卷 1005-1012页

作者： NIE Yuhua CHEN Zhiwu XIE Jieshuo XU Jiexin HE Yinghui CAI Shuqun South China Sea Information Center of State Oceanic Administration Guangzhou 510310China State Key Laboratory of Tropical Oceanography South China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China University of Chinese Academy of Sciences Beijing 100049China Institution of South China Sea Ecology and Environmental Engineering Chinese Academy of SciencesGuangzhou 510301China

Direct numerical simulations are performed to investigate the generation of internal waves by tide-topography interaction in a lab-scale model.The bottom topography is a triangular ridge with two critical slopes.With increasing tidal forcing,subharmonic instabilities are identified,which cause internal wave beams to become unstable and turbulent.Kinetic energy densities in the upward going beams from the ridge top are stronger than those from the ridge bottom,whereas the reverse is true for the energy flux.This disparity between energy and energy flux is due to the existence of strong pressure disturbances near the ridge bottom.On each side of the critical ridge,there exists an amphidromic point,from which internal wave beams are emitted in opposite directions.The calculated energy conversion rate scales linearly with the square of the forcing amplitude and agrees within 13%of theoretical prediction,even when turbulence occurs.The fraction of radiated baroclinic energy becomes saturated in the range of low excursion parameter considered,which agrees with the behavior in large-scale systems wherein mixing parameterizations must be used.The present work enriches the studies on the generation of internal waves over a critical triangular ridge.

关键词： internal wave beam parametric subharmonic instability internal wave energetics tide-topography interaction

internal noise stochastic resonance in CO oxidation on nm-sized palladium particles

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Science China Chemistry 2005年第5期48卷 395-401页

作者： GONG Yubing1,2, HOU Zhonghuai1 & XIN Houwen1 1. Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, China 2. Department of Physics, Yantai Teachers University, Yantai 264025, China Department of Chemical Physics University of Science and Technology of China Hefei China Department of Physics Yantai Teachers University Yantai China

Based on a stochastic mesoscopic model, the influence of internal noise on the oscillatory kinetics of the catalytic oxidation of CO on nm-sized palladium particles is studied, using the chemical Langevin equations, Poisson approximation algorithm, and exact stochastic simulation algorithm. The reaction rate oscillations are of stochastic nature due to considerable internal noise in such mesoscopic systems. It is found that the performance of the stochastic oscillations undergoes a maximum with the variation of internal noise level for a given CO partial pressure, which demonstrates the occurrence of internal noise stochastic resonance. This phe-nomenon implies that optimal internal noise would favor the reaction rate oscillation of CO oxi-dation on nm particles. Such a phenomenon is robust to the change of external parameters, such as CO pressures.

关键词： nanometer-sized palladium particles, surface catalytic CO oxidation, internal noise, stochastic resonance, chemical Langevin equation.

Rapid internal Control Reference Recombinase-Aided Amplification Assays for EBV and CMV Detection

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Biomedical and Environmental Sciences 2021年第8期34卷 650-655页

作者： GAO Yuan TIE Yan Qing ZHAO Lin Qing TAN He DING Nan DING Ya Xin GUO Qi ZHANG Rui Qing WANG Jin Rong CHEN Zi Wei FAN Guo Hao SHEN Xin Xin FENG Zhi Shan MA Xue Jun Hebei Medical University Shijiazhuang 050031HebeiChina NHC Key Laboratory of Medical Virology and Viral Diseases National Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijing 102206China Hebei General Hospital Shijiazhuang 050070HebeiChina Laboratory of Virology Beijing Key Laboratory of Etiology of Viral Diseases in ChildrenCapital Institute of PediatricsBeijing 100020China The Third Xiangya Hospital of Central South University Changsha 410013HunanChina Center for Biosafety Mega-Science Chinese Academy of SciencesWuhan 430071Hubei China

Epstein-Barr virus(EBV)and cytomegalovirus(CMV),two of the most prevalent human herpesviruses,cause a wide spectrum of diseases and symptoms and are associated with serious health problem.In this study,we developed an internal control reference recombinase-aided amplification(ICR-RAA)assay for the rapid detection of EBV and CMV within 30 min.The assay had a sensitivity of 5 and 1 copies/test for EBV and CMV,respectively,with no cross reaction with other pathogens.In comparison with those of the commercial quantitative polymerase chain reaction(qPCR),the sensitivity of the EBV and CMV ICR-RAAs using extracted DNA was 93.33%and 84.84%,respectively;the specificity was 98.75%and 100.00%,respectively;and the Kappa values were 0.930 and 0.892(P<0.05),respectively.In comparison with those of qPCR,the sensitivity of the EBV and CMV ICR-RAAs using the DNA by thermal lysis was 72.22%and 80.00%,respectively;the specificity was 100.00%。

关键词： specificity internal EBV

internal Multiple Prediction Based on Imaging Profile Prediction and Kirchhoff Demigration

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Journal of Ocean University of China 2019年第6期18卷 1360-1370页

作者： QIU Binhuang TAN Jun DAN Zhiwei YU Jiashun YAN Hongyan LIU Baohua YU Kaiben SONG Peng XIE Chuang College of Geophysics Chengdu University of TechnologyChengdu 610059China Laboratory for Marine Mineral Resource Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China CNOOC EnerTech-Drilling&Production Co. Data Processing Co.Zhanjiang 524057China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationQingdao 266100China College of Marine Geo-sciences Ocean University of ChinaQingdao 266100China National Deep Sea Center Qingdao 266100China

This paper introduces an internal multiple prediction method based on imaging profile prediction and Kirchhoff demigration.First,based on an inputted prestack time migration profile,the method predicts the prestack time migration profile that only includes internal multiples by inverse scattering series method.Second,the method uses velocity-weighted Kirchhoff demigration to create shot gathers that contains only internal multiples.internal multiple prediction based on the prestack time migration profile effectively reduces the computational cost of multiple predictions,and the internal-multiple shot gathers created by Kirchhoff demigration remarkably reduces the complexity of the practical problem.internal multiple elimination can be conducted through the combined adaptive multiple subtraction based on event tracing.Synthetic and field data tests show that the method effectively predicts internal multiples and possesses considerable potential in field data processing,particularly in areas where internal multiples develop seriously.

关键词： internal multiple prediction inverse scattering series method Kirchhoff demigration Kirchhoff prestack time migration

Lnc-RP5 Regulates the mi R-129-5p/Notch1/PFV internal Promoter Axis to Promote the Expression of the Prototype Foamy Virus Transactivator Tas

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Virologica Sinica 2020年第1期35卷 73-82页

作者： Shanshan Xu Liujun Chen Yinglian Tang Peipei Yuan Jun Yan Yingcheng Zheng Li Huang Zhi Li Yan Sun Song Han Jun Yin Qin Pan Biwen Peng Xiaohua He Wanhong Liu Department of Allergy Zhongnan Hospital of Wuhan UniversityWuhan 430071China Department of Immunology and Hubei Province Key Laboratory of Allergy and Immunology School of Basic Medical SciencesWuhan UniversityWuhan 430071China Hubei Provincial Key Laboratory of Developmentally Originated Disease Wuhan 430071China College of Life Sciences Shanxi Normal UniversityXi’an 710062China Centre for Medical Research Wuhan UniversityWuhan 430071China

Prototype foamy virus(PFV)is a unique retrovirus that infects animals and humans and does not cause clinical symptoms.Long noncoding RNAs(lncRNAs)are believed to exert multiple regulatory functions during viral infections.Previously,we utilized RNA sequencing(RNA-seq)to characterize and identify the lncRNA lnc-RP5-1086 D14.3.1-1:1(lnc-RP5),which is markedly decreased in PFV-infected cells.However,little is known about the function of lnc-RP5 during PFV infection.In this study,we identified lnc-RP5 as a regulator of the PFV transcriptional transactivator(Tas).Lnc-RP5 enhanced the activity of the PFV internal promoter(IP).The expression of PFV Tas was found to be promoted by lnc-RP5.Moreover,mi R-129-5 p was found to be involved in the lnc-RP5-mediated promotion of PFV IP activity,while the Notch1 protein suppressed the activity of PFV IP and the expression of Tas.Our results demonstrate that lnc-RP5 promotes the expression of PFV Tas through the miR-129-5 p/Notch1/PFV IP axis.This work provides evidence that host lnc RNAs can manipulate PFV replication by employing mi RNAs and proteins during an early viral infection.

关键词： Prototype foamy virus(PFV) lnc-RP5 Transactivator(Tas) internal promoter miR-129-5p

internal Combustion Engine Remains Market Main Force

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船舶经济贸易 2023年第11期 63-68页

作者： Wu Xiuxia 不详

"The internal combustion engine(ICE),a classic power plant,will not be eliminated by the decarbonization era,but as an energy conversion device,still has a long way to go for low-carbon and zero-carbon fuels such as alcohol,hydrogen,ammonia and synthetic fuels."At the 2023 Annual Academic Brand Activity of Annual Conference of the Chinese Society for internal Combustion Engines(CSICE)-2023 Academic Annual Conference of Design and Intelligent Manufacturing held in Shiyan。

关键词： Market internal Engine