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Protective effect of retaining wall on rock avalanche:A case study of Nayong rock avalanche in China

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Journal of Mountain Science 2024年第4期21卷 1215-1230页

作者： wang Zhongfu SHI Fengge HE Siming ZHANG Xusheng wang jingying LIU Enlong North China University of Water Resources and Electric Power Zhengzhou 450046China Hunan Provincial key Laboratory of key Technology on Hydropower Development Changsha 410014China Institute of Mountain Hazards and Environment Chinese Academy of SciencesChengdu 610041China College of Water Resource and Hydropower Sichuan UniversityChengdu 610065China

Rock avalanches are generally difficult to prevent and control due to their high velocities and the extensive destruction they cause.However,barrier structures constructed along the path of a rock avalanche can partially mitigate the magnitudes and consequences of such catastrophic events.We selected a rock avalanche in Nayong County,Guizhou Province,China as a case to study the effect of the location and height of a retaining wall on the dynamic characteristics of rock avalanche by using both actual terrain-based laboratory-model tests and coupled PFC3D-FLAC3D numerical simulations.Our findings demonstrate that a retaining wall can largely block a rock avalanche and its protective efficacy is significantly influenced by the integrity of the retaining wall.Coupled numerical simulation can serve as a powerful tool for analyzing the interaction between a rock avalanche and a retaining wall,facilitating precise observations of its deformation and destruction.The impact-curve characteristics of the retaining wall depend upon whether or not the rock avalanche-induced destruction is taken into account.The location of the retaining wall exerts a greater influence on the outcome compared to the height and materials of the retaining wall,while implementing a stepped retaining-wall pattern in accordance with the terrain demonstrates optimal efficacy in controlling rock avalanche.

关键词： Rock avalanche Laboratory model test Retaining wall PFC^(3D) FLAC^(3D) Impact force

Review of Research Advances in CFD Techniques for the Simulation of Urban Wind Environments

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Fluid Dynamics & Materials Processing 2022年第2期18卷 449-462页

作者： Pengfei Ju Mingrui Li jingying wang Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical EngineeringTianjin University of TechnologyTianjin300384China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education(Tianjin University of Technology) Tianjin300384China School of Energy and Power Engineering Shandong UniversityJinan250061China Shandong Engineering Laboratory for High-Efficiency Energy Conservation and Energy Storage Technology&Equipment Shandong UniversityJinan250061China

Computational fluid dynamics(CFD)has become the main method for the prediction of the properties of the external wind environment in cities and other urban contexts.A review is presented of the existing literature in terms of boundary conditions,building models,computational domains,computational grids,and turbulence models.Some specific issues,such as the accuracy/computational cost ratio and the exploitation of existing empirical correlations,are also examined.

关键词： Computational fluid dynamics wind environment pre-processing settings

Numerical Investigation into the Transient Behavior of the Spike-Type Rotating Stall for a Transonic Compressor Rotor

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Fluid Dynamics & Materials Processing 2022年第3期18卷 761-773页

作者： Pengfei Ju Fangfei Ning Zhiting Tong jingying wang Tianjin Key Laboratory for Advanced Mechatronic System Design and Intelligent Control School of Mechanical EngineeringTianjin University of TechnologyTianjin300384China National Demonstration Center for Experimental Mechanical and Electrical Engineering Education(Tianjin University of Technology) Tianjin300384China Research Institute of Aero-Engine Beihang UniversityBeijing100191China National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics School of Energy and Power EngineeringBeihang UniversityBeijing100191China School of Energy and Power Engineering Shandong UniversityJinan250061China Shandong Engineering Laboratory for High-Efficiency Energy Conservation and Energy Storage Technology&Equipment Shandong UniversityJinan250061China

In this paper,a numerical investigation into a spike-type rotating stall process is carried out considering a transonic compressor rotor(the NASA Rotor 37).Through solution of the Unsteady Reynolds-Averaged Navier-Stokes(URANS)equations,the evolution process from an initially circumferentially-symmetric near-stall flow field to a stable stall condition is simulated without adding any artificial disturbance.At the near-stall operating point,periodic fluctuations are present in the overall flow of the rotor.Moreover,the blockage region in the channel periodically shifts from middle span to the tip.This fluctuating condition does not directly lead to stall,while the full-annulus calculation eventually evolves to stall.Interestingly,a kind of“early disturbance”feature appears in the dynamic signals,which propagates forward ahead of the rotor.

关键词： Transonic compressor spike stall numerical simulation early disturbance dynamic signal

Numerical Application of the Flamelet Model to Supersonic Turbulent Combustion

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Fluid Dynamics & Materials Processing 2022年第4期18卷 957-971页

作者： Yongkang Zheng Qinxue Jiang Hao Tian Youda Ye jingying wang China Aerodynamics Research and Development Center Mianyang621000China School of Energy and Power Engineering Shandong UniversityJinan250061China

In this study,the flow field structure inside a scramjet combustor is numerically simulated using the flamelet/progress variable model.Slope injection is considered,with fuel mixing enhanced by means of a streamwise vortex.The flow field structure and combustion characteristics are analyzed under different conditions.Attention is also paid to the identification of the mechanisms that keep combustion stable and support enhanced mixing.The overall performances of the combustion chamber are discussed.

关键词： Steady flamelet model flamelet/progress variable model supersonic combustion

OsASHL1 and OsASHL2,two members of the COMPASS-like complex,control floral transition and plant development in rice

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Journal of Genetics and Genomics 2022年第9期49卷 870-880页

作者： Guangxin Zhao jingying wang Xi Chen Hanjing Sha Xin Liu Yunfei Han Guankai Qiu Fantao Zhang Jun Fang Key Laboratory of Soybean Molecular Design Breeding Northeast Institute of Geography and AgroecologyChinese Academy of SciencesHarbinHeilongjiang 150081China University of Chinese Academy of Sciences Beijing 100049China College of Agriculture Northeast Agricultural UniversityHarbinHeilongjiang 150030China College of Life Sciences Jiangxi Normal UniversityNanchangJiangxi 330022China

COMPASS or COMPASS-like is a highly conserved polyprotein complex in eukaryotes that is often involved in methylation of histone H3 lysine 4(H3K4).However,the biological function of this complex in rice(Oryza sativa)is unclear.Here,we report the identifiction of their functions in growth and development.The osashl1osashl2 double mutant shows a dwarf and late-flowering phenotype.Lower expression of Ehd1,OsVIL4,and OsMADS51 in the osashl1 osashl2 double mutant background accompanies a delayed vegetative growth phase and photoperiod-sensitive phase compared with that in wild type.Notably,there is less H3K4mono-,di-and tri-methylation genome-wide in the double mutant,in particular less H3K4 tri-methylation at OsVIL4.Consistent with this result,knockout of OsVIL4 gives rise to a late-flowering phenotype similar to that of the osashl1 osashl2 double mutant,suggesting that OsVIL4 is a target of the COMPASS-like complex.In addition,the expression of key genes in brassinosteroid and gibberellic acid metabolism is altered in the osashl1 osashl2 double mutant,suggesting that the COMPASS-like complex regulates plant growth and development by modulating the levels of these two phytohormones.In summary,we demonstrate that OsASHL1 and OsASHL2 are important for floral transition and plant development.

关键词： Rice(Oryza sativa) OsASHL1 OsASHL2 Flowering COMPASS-like H3K4 methylation

TNFSF15 facilitates the differentiation of CD11b^(+) myeloid cells into vascular pericytes in tumors

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Cancer Biology & Medicine 2023年第11期20卷 869-884页

作者： Xiangxiang Gu Yipan Zhu Cancan Zhao Yixin Cao jingying wang Qiangzhe Zhang Luyuan Li State Key Laboratory of Medicinal Chemical Biology and College of Pharmacy Nankai Universityand Haihe Laboratory of Cell EcosystemTianjin 300350China

Objective:Immature vasculature lacking pericyte coverage substantially contributes to tumor growth,drug resistance,and cancer cell dissemination.We previously demonstrated that tumor necrosis factor superfamily 15(TNFSF15)is a cytokine with important roles in modulating hematopoiesis and vascular homeostasis.The main purpose of this study was to explore whether TNFSF15 might promote freshly isolated myeloid cells to differentiate into CD11b^(+) cells and further into pericytes.Methods:A model of Lewis lung cancer was established in mice with red fluorescent bone marrow.After TNFSF15 treatment,CD11b^(+) myeloid cells and vascular pericytes in the tumors,and the co-localization of pericytes and vascular endothelial cells,were assessed.Additionally,CD11b^(+) cells were isolated from wild-type mice and treated with TNFSF15 to determine the effects on the differentiation of these cells.Results:We observed elevated percentages of bone marrow-derived CD11b^(+)myeloid cells and vascular pericytes in TNFSF15-treated tumors,and the latter cells co-localized with vascular endothelial cells.TNFSF15 protected against CD11b^(+)cell apoptosis and facilitated the differentiation of these cells into pericytes by down-regulating Wnt3a-VEGFR1 and up-regulating CD49e-FN signaling pathways.Conclusions:TNFSF15 facilitates the production of CD11b^(+) cells in the bone marrow and promotes the differentiation of these cells into pericytes,which may stabilize the tumor neovasculature.

关键词： TNFSF15 myeloid cell neovascularization CD11b^(+)cell pericyte

Numerical Study of High-Temperature Nonequilibrium Flow around Reentry Vehicle Coupled with Thermal Radiation

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Fluid Dynamics & Materials Processing 2020年第3期16卷 601-613页

作者： jingying wang Fangzhou Han Li Lei Chunhian Lee School of Energy and Power Engineering Shandong UniversityJinan250061China

Accurate aerodynamic heating prediction is of great significance to current manned space flight and deep space exploration missions.The temperature in the shock layer surrounding the reentry vehicle can reach up to 10,000 K and result in remarkable thermochemical nonequilibrium,as well as considerable radiative heat transfer.In general,high-temperature flow simulations coupled with thermal radiation require appropriate numerical schemes and physical models.In this paper,the equations governing hypersonic nonequilibrium flow,based on a three-temperature model combined with a thermal radiation solving approach,are used to investigate the radiation effects in the reentry shock layer.An axisymmetric spherical case shows that coupling the flow-field simulation with radiation has a scarce influence on the convective heating prediction,but has some impact on the radiative heating calculation.In particular,for the Apollo capsule reentry,both the absorption coefficient and incident radiation are remarkable inside the shock layer.The radiative heating maximum reaches nearly 38%of that of the convective heating making a considerable contribution to the total aerodynamic heating.These results indicate that in the hypersonic regime,in order to account for the total heating,it is necessary to simulate the high-temperature thermochemical nonequilibrium flows coupled with thermal radiation.

关键词： Reentry nonequilibrium aerodynamic heating thermal radiation

吉林省西部盐碱地综合开发多情景模拟与水资源效应

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水土保持学报 2024年第3期38卷 159-167,176页

作者：李文博姜博文王晶滢东北大学文法学院沈阳110169 辽宁土地利用与保护研究基地沈阳110169 辽宁省自然资源土地保护与利用重点实验室沈阳110169 吉林大学地球科学学院长春130061

[目的]盐碱地综合开发利用是提高农业生产力、践行大食物观的必然选择。但受限于开发利用模式单一、耗水压力较大,亟待探索多元化治理模式并依据其水资源效应开展优化调控。[方法]以吉林省西部地区为研究区,采用FLUS模型预测2030年盐碱... 详细信息

[目的]盐碱地综合开发利用是提高农业生产力、践行大食物观的必然选择。但受限于开发利用模式单一、耗水压力较大,亟待探索多元化治理模式并依据其水资源效应开展优化调控。[方法]以吉林省西部地区为研究区,采用FLUS模型预测2030年盐碱地资源在自然发展、粮食安全、粮饲综合开发和生态安全4种情景下的开发利用格局,并对不同情景下的产水量变化进行评估。[结果](1)2000—2020年研究区开发利用盐碱地1540.18 km^(2),主要被恢复为草地或开垦为耕地,但其中旱地次生退化风险较高。(2)不同情景下盐碱地开发均以耕地利用为主。粮食安全情景下水田和旱地开垦面积占比分别为67.48%,4.23%。相较于自然发展情景,粮饲综合开发情景下盐碱地恢复为草地的面积增加139.18 km^(2),生态安全情景下生态用地规模显著提高。(3)至2030年,4种发展情景下研究区产水量较基期均有所下降,生态安全情景下降幅度最大,达到3.71×10^(8)m^(3)。相比之下,粮饲综合开发情景充分保障粮食和饲草生产,同时缓和盐碱地治理所导致的水资源压力。[结论]松嫩平原盐碱地开发利用应充分考虑粮饲综合开发模式,统筹粮食和饲草供应,协调粮食和生态安全,以大食物观引领国土空间生态修复和退化土地的开发利用。

关键词：盐碱地综合开发多情景模拟产水量吉林西部

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BOPPPS模式下工程流体力学实验教学研究

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实验室研究与探索 2024年第5期43卷 206-210页

作者：王晓哲刘丽萍王京盈雷丽山东大学能源与动力工程学院济南250061

为实现工程教育认证背景下的人才培养要求,结合能源动力类教学实践特点,利用BOPPPS教学模式对工程流体力学实验教学进行改革。以知识引入、设定目标、课前评估、参与学习、课下评估、课后总结为六大课程设计要素,从实验教学脚本的设计... 详细信息

为实现工程教育认证背景下的人才培养要求,结合能源动力类教学实践特点,利用BOPPPS教学模式对工程流体力学实验教学进行改革。以知识引入、设定目标、课前评估、参与学习、课下评估、课后总结为六大课程设计要素,从实验教学脚本的设计、课程思政资源的挖掘、多种教学方法的有机融合、多种形式教学资源的应用等方面开展研究,同时改进实验教学评价方法,建立立体化、全流程实验教学体系,探索创新型实验教学新方法。

关键词： BOPPPS模式流体力学实验教学工程认证线上线下混合式教学