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A comparative study of the main factors controlling geohazards induced by 10 strong earthquakes in Western China since the Wenchuan earthquake in 2008

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China Geology 2023年第1期6卷 70-84页

作者： Chao Peng Zhi-qiang Yin Xu-jiao Zhang Hai Shao Ming-fei Pang China University of Geosciences(Beijing) Beijing 100029China China Institute of Geo-Environment Monitoring China Geological SurveyMinistry of Natural ResourcesBeijing 100081China China University of Geosciences Wuhan 430074China

Determining the main controlling factors of earthquake-triggered geohazards is a prerequisite for studying earthquake geohazards and post-disaster emergency response.By studying these factors,the geomorphic and geological factors controlling the nature,condition,and distribution of earthquake-induced geohazards can be analyzed.Such insights facilitate earthquake disaster prediction and emergency response planning.The authors combined field investigations and spatial data analysis to examine geohazards induced by seismic events,examining ten earthquakes including the Wenchuan,Yushu,Lushan events,to elucidate the main control factors of seismic geohazard.The authors observed that seismic geohazard occurrence is usually affected by many factors,among which active nature of the seismogenic fault,seismic peak ground acceleration(PGA),topographic slope and geomorphic height differences,and distance from the fault zone and river system are the most important.Compared with strike-slip earthquakes,thrust earthquakes induce more high-altitude and high-speed remote landslides,which can cause great harm.Slopes of 0°–40°are prone to secondary seismic geohazards,which are mainly concentrated 0–6 km from the river system.Secondary geohazards are not only related to seismogenic fault but also influenced by the associated faults in the earthquake area.The maximum seismic PGA and secondary seismic geohazard number are positively correlated,and the horizontal and vertical ground motions play leading and promoting roles in secondary geohazard formation,respectively.Through the research,the spatial distribution of seismic geohazards is predicted,providing a basis for the formulation of emergency response plans following disasters.

关键词： Wenchuan earthquake Geohazards Main control factors Comparative study Geological disater survey engineering Western China

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表面活性剂浓度对球形气泡界面和尾流的影响

工程热物理学报 2020年第2期41卷 374-379页

作者：庞明军费洋常州大学机械工程学院常州213164 常州大学江苏省绿色过程装备重点实验室常州213164

发展了一种研究气泡界面污染程度的数值模型,并用其对流场中不同表面活性剂浓度下、上浮气泡的界面参量和周围流场进行了模拟研究。该模型假设吸附于气泡界面的表面活性剂分布在毗邻气液界面的薄吸附层中,且气泡界面上表面活性剂的吸附... 详细信息

发展了一种研究气泡界面污染程度的数值模型,并用其对流场中不同表面活性剂浓度下、上浮气泡的界面参量和周围流场进行了模拟研究。该模型假设吸附于气泡界面的表面活性剂分布在毗邻气液界面的薄吸附层中,且气泡界面上表面活性剂的吸附与解吸过程也发生于此;界面切应力为界面浓度的函数。研究发现:气泡界面的流动性会因表面活性剂的吸附而降低,该现象会增大气泡周围流域中切向速度在界面法向上的变化量,从而对界面性质和周围流场产生影响;由于对流的作用和吸附-解吸动态平衡的存在,气泡前部界面不完全干净,且受污染界面的流动性也不完全为零。

关键词：球形气泡表面活性剂数值模型界面性质流场

Numerical study on hydrodynamic characteristics of spherical bubble contaminated by surfactants under higher Reynolds numbers

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Chinese Journal of Chemical Engineering 2022年第5期35卷 268-283页

作者： Tao Sun mingjun pang Yang fei School of Mechanical Engineering and Rail Transit Changzhou UniversityChangzhou 213164China

It is of significance to investigate deeply the hydrodynamic featu res of the bubble co ntaminated by impurities in view of the fact that the industrial liquid is difficult to keep absolutely pure.On the basis of the finite volume method,the bubble interface contaminated by the surfactant(1-pentanol)is achieved through solving the concentration transport equations in liquid and along the bubble interface,and solving the absorption and desorption equation at the bubble interface.And the three-dimensional momentum equation is solved at the same time.It is investigated in detail on the influence of interfacial contamination degrees(described with the cap angleθ)on hydrodynamic characteristics of the spherical bubble when the bubble Reynolds number(Re)is larger than 200.Theθis realized by changing the surfactant concentration(C_(0)) in liquid.The present results show that the hydrodynamic characteristics,such as interfacial concentration,interfacial shear stress,interfacial velocity and wake flow,are related to both Re and C_(0) for the contaminated bubble.When C_(0) is relatively low in liquid(i.e.,the contamination degree of the bubble interface is relatively slight),the hydrodynamic characteristics of the bubble can still keep the 2 D features even if Re>200.The decrease ofθor the increase of Re can promote the appearance of the unsteady wake flow.For the present investigation,when Re>200 andθ≤60°,the hydrodynamic characteristics of the bubble show the 3D phenomena,which indicates that axisymmetric model is no longer valid.

关键词： Bubble Higher Reynolds number Interfacial parameters Wake flow Adsorption Desorption

Aging induces severe SIV infection accompanied by an increase in follicular CD8+T cells with overactive STAT3 signaling

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Cellular & Molecular Immunology 2022年第9期19卷 1042-1053页

作者： Hong-Yi Zheng Xue-Hui Wang Xiao-Yan He Min Chen ming-Xu Zhang Xiao-Dong Lian Jia-Hao Song Yan Hu Wei pang Yun Wang Zheng-fei Hu Long-Bao Lv Yong-Tang Zheng Key Laboratory of Animal Models and Human Disease Mechanisms of Chinese Academy of Sciences KIZ-CUHK Joint Laboratory of Bioresources and Molecular Research in Common DiseasesCenter for Biosafety Mega-ScienceKunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan650223China School of Life Sciences University of Science and Technology of ChinaHefeiAnhui230026China Kunming College of Life Science University of Chinese Academy of SciencesKunmingYunnan650204China National Resource Center for Non-Human Primates National Research Facility for Phenotypic&Genetic Analysis of Model Animals(Primate Facility)Kunming Institute of ZoologyChinese Academy of SciencesKunmingYunnan650107China

The number of elderly people living with HIV is increasing globally,and the condition of this population is relatively complicated due to the dual effects of aging and HIV infection.However,the impact of HIV infection combined with aging on the immune homeostasis of secondary lymphoid organs remains unclear.Here,we used the simian immunodeficiency virus mac239(SIVmac239)strain to infect six young and six old Chinese rhesus macaques(ChRMs)and compared the infection characteristics of the two groups in the chronic stage through multiplex immunofluorescence staining of lymph nodes.The results showed that the SIV production and CD4/CD8 ratio inversion in old ChRMs were more severe than those in young ChRMs in both the peripheral blood and the lymph nodes,especially when a large number of CD8+T cells infiltrated the follicles and germinal centers.STAT3 in these follicular CXCR5+CD8+T cells was highly activated,with high expression of granzyme B,which might be caused by the severe inflammatory milieu in the follicles of old ChRMs.This study indicates that aging may be a cofactor involved in SIV-induced immune disorders in secondary lymphoid tissues,affecting the effective antiviral activity of highly enriched follicular CXCR5+CD8+cells.

关键词： SIV Aging Follicle CD8 T cells

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超声波电动机自动优化设计研究

微特电机 2011年第6期39卷 26-28,36页

作者：庞亚飞杨明上海交通大学上海200240

超声波电动机的优化设计包含振动模态优化,激励方式或区域设定,电机结构、尺寸优化等等,以满足电机工作需求并改善其输出性能。介绍了一种基于MATLAB和ANSYS的自动优化方法,即利用MATLAB运行优化算法,建立APDL参数化分析模型,并反复调用... 详细信息

超声波电动机的优化设计包含振动模态优化,激励方式或区域设定,电机结构、尺寸优化等等,以满足电机工作需求并改善其输出性能。介绍了一种基于MATLAB和ANSYS的自动优化方法,即利用MATLAB运行优化算法,建立APDL参数化分析模型,并反复调用ANSYS分析对超声波电动机进行自动优化。文中以矩形板超声波电动机的驱动足优化为例,给出了驱动足的位置设定和形状优化过程,并对MATLAB与ANSYS程序之间的调用、接口及数据交互方面做了详细说明。

关键词：超声波电动机自动优化 MATLAB ANSYS

Removal and occurrence state transformation of Ti impurity in Gd metal

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Rare Metals 2021年第8期40卷 2320-2326页

作者： Zhen-fei Yang Si-ming pang Shi-Hong Yan Hong-Bo Yang Xiao-Wei Zhang Qiong Zhu De-Hong Chen Dao-Gao Wu General Research Institute for Nonferrous Metals Beijing100088China National Engineering Reseach Center for Rare Earth Materials Grirem Advanced Materials Co.Ltd.Beijing100088China

The interaction mechanism of B and Ti in liquid Gd metal was theoretically analyzed,and the occurrence state transformation and removal of Ti impurity were experimentally analyzed in this study.The research results indicated that the B additive reacted with the Ti impurity in liquid Gd metal to form the high-melting-point TiB_(2)at 1673 K.Owing to the low density of TiB_(2)that is far lower than that of Gd,TiB_(2)floated up to the liquid surface,and then,the Ti impurity could be effectively removed from Gd metal.Prolonging melting time and increasing B additive amount could increase Ti removal rate,but the increase in the rate slows beyond a certain duration and B content.The recommended operating parameter,melting time of 60 min and B additive content of 0.1394 wt%could reduce Ti content from 0.1534 wt%to 0.0433 wt%,and the removal rate was 71.9%.

关键词： Gd metal Ti impurity B additive TiB_(2)

Modulation of the Intraseasonal Variability of Pacific-Japan Pattern by ENSO

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Journal of Meteorological Research 2020年第3期34卷 546-558页

作者： Ying LI fei LIU pang-Chi HSU Earth System Modeling and Climate Dynamics Research Center Nanjing University of Information Science&TechnologyNanjing 210044

This study investigates how the El Nino-Southern Oscillation(ENSO)modulates the intraseasonal variability(ISV)of Pacific-Japan(PJ)teleconnection pattern.The PJ index during boreal summer is constructed from the empirical orthogonal function(EOF)of the 850-hPa zonal wind(U850)anomalies.Distinct periods of the PJ index are found during El Nino and La Nina summers.Although ISV of the PJ pattern is significant during 10-25 days for both types of summers,it peaks on Days 30 and 60 in El Nino and La Nina summers respectively.During El Nino summers,the 30-day ISV of PJ pattern is related to the northwestward propagating intraseasonal oscillation(ISO)over the western North Pacific(WNP),which is originated from the tropical Indian Ocean(IO).During La Nina summers,the 60-day ISV of PJ pattern is related to the northeastward propagating ISO from the tropical IO.The low-frequency ISV modes in both El Nino and La Nina summers are closely related to the boreal summer ISO(BSISO),and the high-frequency ISV modes over WNP are related to the quasi-biweekly oscillation.The underlying mechanisms for these different evolutions are also discussed.

关键词： Pacific–Japan(PJ)pattern El Nino–Southern Oscillation(ENSO) intraseasonal variability(ISV) intraseasonal oscillation(ISO) intraseasonal timescale low-frequency ISV mode boreal summer ISO

Changes in polar amplification in response to increasing warming in CMIP6

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Atmospheric and Oceanic Science Letters 2021年第3期14卷 54-59页

作者： Shenlin Cai pang-Chi Hsu fei Liu Earth System Modeling and Climate Dynamics Research Center Nanjing University of Information Science and TechnologyNanjingChina School of Atmospheric Sciences Key Laboratory of Tropical Atmosphere-Ocean System Ministry of EducationSun Yat-Sen UniversityChina Southern Marine Science and Engineering Guangdong Laboratory ZhuhaiChina

由于全球变暖,极地地区的气候经历了明显的变暖放大.在本项研究中,我们根据CMIP6模式的三种变暖情景(SSP1-2.6,SSP2-4.5和SSP5-8.5)下,极地放大变化对各个反馈机制(包括普朗克,温度递减率,云,水蒸气,反照率反馈,CO_(2)强迫,海洋热吸收... 详细信息

由于全球变暖,极地地区的气候经历了明显的变暖放大.在本项研究中,我们根据CMIP6模式的三种变暖情景(SSP1-2.6,SSP2-4.5和SSP5-8.5)下,极地放大变化对各个反馈机制(包括普朗克,温度递减率,云,水蒸气,反照率反馈,CO_(2)强迫,海洋热吸收和大气热传输)的响应进行了分析.结果表明,通过用"辐射核"方法量化不同反馈机制对地表温度的增温贡献,北极放大(AA)强于南极放大(ANA),由温度递减率反馈主导,其次是反照率和普朗克反馈.此外,海洋的热吸收导致冬季比夏季有更强的极地变暖.在冬季,温度递减率反馈主导了AA大于ANA.AA和ANA的模式间差异随着全球变暖的增强而减小.

关键词：北极放大南极放大辐射核 CMIP6 全球变暖

Mechanism studies of the activation of DNA methyltransferase DNMT1 triggered by histone H3 ubiquitination,revealed by multi-scale molecular dynamics simulations

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Science China(Life Sciences) 2023年第2期66卷 313-323页

作者： Jixue Sun fei Liu Longxiao Yuan Ning-Ning pang Bing Zhu Na Yang State Key Laboratory of Medicinal Chemical Biology College of Pharmacy and Key Laboratory of Medical Data Analysis and Statistical Research of TianjinNankai UniversityTianjin 300353China National Laboratory of Biomacromolecules CAS Center for Excellence in BiomacromoleculesInstitute of BiophysicsChinese Academy of SciencesBeijing 100101China

DNMT1 is a DNA methyltransferase that catalyzes and maintains methylation in CpG dinucleotides.It blocks the entrance of DNA into the catalytic pocket via the replication foci targeting sequence(RFTS)domain.Recent studies have shown that an H3-tail-conjugated two-mono-ubiquitin mark(H3Ub2)activates DNMT1 by binding to the RFTS domain.However,the activation mechanism of DNMT1 remains unclear.In this work,we combine various sampling methods of extensive simulations,including conventional molecular dynamics,Gaussian-accelerated molecular dynamics,and coarse-grained molecular dynamics,to elucidate the activation mechanism of DNMT1.Geometric and energy analyses show that binding of H3Ub2 to the RFTS domain of DNMT1 results in the bending of theα4-helix in the RFTS domain at approximately 30°–35°,and the RFTS domain rotates~20°anti-clockwise and moves~3?away from the target recognition domain(TRD).The hydrogen-bonding network at the RFTSTRD interface is significantly disrupted,implying that the RFTS domain is dissociated from the catalytic core,which contributes to activating the auto-inhibited conformation of DNMT1.These results provide structural and dynamic evidence for the role of H3Ub2 in regulating the catalytic activity of DNMT1.

关键词： DNA methyltransferase conformational change molecular dynamics simulation activation molecular mechanism