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Erosion control of Chinese loess using polymer SH and ryegrass

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Journal of Mountain Science 2024年第6期21卷 2043-2058页

作者： YING Chunye LI Lanxing MAKEEN Gehad Mohamed Hossam liu yabin School of Geological Engineering Qinghai UniversityXining 810016China Key Laboratory of Genozoic Resource&Environment in North Margin of the Tibetan Plateau Xining 810016China Faculty of Engineering China University of GeosciencesWuhan 430074China Faculty of Science Ain Shams UniversityCairo 11566Egypt

The China Loess Plateau is subjected to severe soil erosion triggered by intense rainfall,resulting in significant harm and losses to both human society and the natural *** this study,a novel technique for managing loess erosion is introduced,which involves the utilization of a combined polymer SH and ryegrass.A comprehensive series of tests were undertaken,including rainfall erosion tests,disintegration experiments,and scanning electron microscopy examinations,to assess the accumulative sediment yield(ASY),disintegration ratio,and microstructural features of both untreated and treated loess *** results showed a significant reduction in ASY with increased dry density of untreated ***,the combined technique effectively controlled erosion,limiting ASY to 266.2 g/cm^(2)in 60 *** was approximately one-sixth,one-ninth,and one-fifteenth of the ASY in SH-treated loess(L-SH),ryegrass-treated loess(L-R),and untreated loess,*** resisted disintegration better than ryegrass alone but slightly less than *** improvement was due to the combined effect of SH and ryegrass,which reduced raindrop impact,improved loess microstructure,and boosted ryegrass *** innovative technique holds the potential to be applied as a field-scale technique in the Loess Plateau region of China.

关键词： Loess Plateau Loess erosion Ryegrass Polymer SH Erosion control Microstructure

Mechanism underlying the uprooting of taproot-type shrub species in the loess area of northeastern Qinghai-Xizang Plateau, China

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Journal of Arid Land 2024年第10期16卷 1426-1443页

作者： LIANG Shen WANG Shu liu yabin PANG Jinghao ZHU Haili LI Guorong HU Xiasong School of Geological Engineering Qinghai UniversityXining 810016China Key Laboratory of Genozoic Resource&Environment in North Margin of the Tibet Plateau Xining 810016China

Characteristics of root pullout resistance determine the capacity to withstand uprooting and the slope protection ability of ***,mechanism underlying the uprooting of taproot-type shrub species in the loess area of northeastern Qinghai-Xizang Plateau,China remains *** this study,a common taproot-type shrub,Caragana korshinskii Kom.,in northeastern Qinghai-Xizang Plateau was selected as the research *** of root-soil interaction of vertical root of *** was investigated via a combination of a single-root pullout test and numerical simulation *** results indicated that,when pulling vertically,axial force of the roots decreased with an increase in buried depth,whereas shear stress at root-soil interface initially increased and then decreased as burial depths *** the same buried depth,both axial force and shear stress of the roots increased with the increase in pullout *** stress and plastic zone of the soil surrounding the root were symmetrically distributed along the root *** zone was located close to the surface and was caused primarily by tensile *** nonvertical pulling,symmetry of shear stress and plastic zone of the soil surrounding the root was *** observed larger shear stress and plastic zones on the side facing the direction of root *** zone included both shear and tensile *** force of the root system near the surface decreased as deflection angle of the pullout force *** different rainfall infiltration depths had the same vertical pulling force,root axial force decreased with the increase of rainfall infiltration depth and total root displacement *** rainfall infiltration,shear stress and plastic zone of the soil surrounding the root were prone to propagating deeper into the *** findings provide a foundation for further investigation of soil reinforcement and slope protection mechanisms of taproot-type shrub spec

关键词： Qinghai-Xizang Plateau shrub roots pullout test numerical simulation mechanism root-soil interaction

Shear resistance characteristics and influencing factors of root-soil composite on an alpine metal mine dump slope with different recovery periods

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Journal of Mountain Science 2024年第3期21卷 835-849页

作者： PANG Jinghao LIANG Shen liu yabin LI Shengwei WANG Shu ZHU Haili LI Guorong HU Xiasong Department of Geological Engineering Qinghai UniversityXining 810016China Key Laboratory of Genozoic Resource&Environment in North Margin of the Tibetan Plateau Xining 810016China

Artificial vegetation restoration is the main measure for vegetation restoration and soil and water conservation in alpine mine dumps on the Qinghai-Tibet Plateau,***,there are few reports on the dynamic changes and the influencing factors of the soil reinforcement effect of plant species after artificial vegetation restoration under different recovery *** selected dump areas of the Delni Copper Mine in Qinghai Province,China to study the relationship between the shear strength and the peak displacement of the root-soil composite on the slope during the recovery period,and the influence of the root traits and soil physical properties on the shear resistance characteristics of the root-soil composite via in situ direct shear *** results indicate that the shear strength and peak displacement of the rooted soil initially decreased and then increased with the increase of the recovery *** shear strength of the rooted soil and the recovery period exhibited a quadratic function *** is no significant function relationship between the peak displacement and the recovery *** positive correlations(P0.05)between the shear strength of the root-soil composite and the root length density,and the root volume ratio of the coarse roots to the fine roots.A significant negative linear correlation(P0.05)with the root traits,other soil physical property indices(the moisture content and dry density of the soil),and slope *** coarse-grain content is the main factor controlling the peak displacement of the rooted soil.

关键词： Alpine mine dump Artificial vegetation restoration period Rooted soil Shear resistance characteristics Root traits Soil physical properties

CUES OF PROSODIC BOUNDARIES IN CHINESE SPONTANEOUS SPEECH

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CUES OF PROSODIC BOUNDARIES IN CHINESE SPONTANEOUS SPEECH

Study of Shaft Driving Force Simulation of Trees Cones Acquisition Robot

作者： liu yabin Li Aijun Institute of Linguistics CASS

This paper analyzes the acoustic features of prosodic boundaries at all levels in Chinese spontaneous speech using statistical method, and manages to find the cues of prosodic phrase boundaries in spontaneous speech.

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Chinese Forestry Science and Technology 2012年第3期11卷 59-60页

作者： Ding Haojie liu yabin Shanghai Finance University

The process that tree cone acquisition robot gets cones has been simulated with the process that human bends or stretches his arms in some load. And then the shaft driving force simulation of tree cone acquisition robot in the wording process was analyzed according to biomechanics laws by system modeling simulation analysis software that is used in current *** forces of the shafts at shoulder joint and elbow joint of the robot were analyzed,meanwhile,were calculated and drew up the figures by using Maple ***,the analytical results verified the correctness of the theory analysis with Solid Dynamics *** from the study,the findings provide important theory and parameters for improving the trees cones acquisition robot.

关键词： trees cones acquisition robot biomechanics MATLAB solid dynamics software

Clinical outcomes of primary rotating-hinge knee arthroplasty for knees with severe deformity

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Chinese Medical Journal 2014年第9期127卷 1791-1793页

作者： Zhang Fujiang liu yabin Xiao Yu liu Wenbin Department of Joint Reconstruction Tianjin Hospital Tianjin Medical University Tianjin 300210 China

Rotating-hinge total knee prostheses are often used for the treatment of global instability or severe bone loss around the knee,which is often accompanied by severe deformity.1 Competent and functional collateral ligaments are a prerequisite for performance of conventional total knee arthroplasty （TKA）.In cases of primary surgery for knees with severe deformities or in revision surgery for knees with substantial bone loss,standard condylar implants do not allow for proper stabilization of the *** these circumstances,condylar TKA designs will fail within a short period of time,or other complications such as anterior knee pain will occur soon after surgery.2

关键词： knee with severe deformity rotating-hinge knee

Effects of fluid flow rate and viscosity on gravel-pack plugging and the optimization of sand-control wells production

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Petroleum Exploration and Development 2019年第6期46卷 1251-1259页

作者： DONG Changyin ZHOU Yugang CHEN Qiang ZHU Chunming LI Yanlong LI Xiaobo liu yabin Key Laboratory of Unconventional Oil&Gas Development(China University of Petroleum(East China)) Ministry of EducationQingdao 266580China Qingdao Institute of Marine Geology Qingdao 266073China Production Optimization-COSL Tianjin 300459China

Series of experiments were performed to simulate the invasion of formation sand into and the plugging process of gravel-pack at different viscosities and flowing rates of *** types of formation sands with the medium size of 0.10 mm and 0.16 mm and the quartz sand and ceramsite of 0.6-1.2 mm were used in the experiments.A new viscosity-velocity index(the product of fluid viscosity and velocity)was put forward to characterize the influencing mechanism and law of physical property and flow condition of formation fluid on gravel-pack plugging,and a new method to optimize the production rate of wells controlling sand production with gravel-packing was *** results show that the permeability of formation sand invaded zone and final permeability of plugged gravel-pack have negative correlations with viscosity and flow velocity of fluid,the higher the flow velocity and viscosity,the lower the permeability of formation sand invaded zone and final permeability of plugged gravel-pack will *** flow velocity and viscosity of fluid are key factors affecting plugging degree of the gravel *** viscosity-velocity index(v-v index)can reflect the flow characteristics of fluid very well and make it easier to analyze the plugging mechanism of gravel *** different combinations of fluid viscosity and flow velocity,if the v-v index is the same or close,their impact on the final gravel permeability would be the same or *** the increase of the v-v index,the permeability of plugged gravel zone decreases first,then the reduction rate slows down till the permeability *** optimizing production and increasing production step by step,the optimal working scheme for sand-control well can reduce the damage to gravel-pack zone permeability caused by sand-carrying fluid effectively,and increase well productivity and extend the sand control life.

关键词： gravel-pack sand retention experiment plugging law viscosity-velocity index working scheme optimization method plugging simulation

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Characterization of alpine meadow surface crack and its correlation with root-soil properties

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Journal of Arid Land 2024年第6期16卷 834-851页

作者： WU Yuechen ZHU Haili ZHANG Yu ZHANG Hailong liu Guosong liu yabin LI Guorong HU Xiasong School of Geological Engineering Qinghai UniversityXining 810016China Key Laboratory of the Cenozoic Resources and Environment on the North Rim of the Qinghai-Tibet Plateau Xining 810016China Qinghai Provincial Transportation Planning and Design Research Institute Co.Ltd. Xining 810002China

Quantifying surface cracks in alpine meadows is a prerequisite and a key aspect in the study of grassland crack *** characterization indices are crucial for the quantitative characterization of complex cracks,serving as vital factors in assessing the degree of cracking and the development *** far,research on evaluating the degree of grassland degradation through crack characterization indices is rare,especially the quantitative analysis of the development of surface cracks in alpine meadows is relatively ***,based on the phenomenon of surface cracking during the degradation of alpine meadows in some regions of the Qinghai-Tibet Plateau,we selected the alpine meadow in the Huangcheng Mongolian Township,Menyuan Hui Autonomous County,Qinghai Province,China as the study area,used unmanned aerial vehicle(UAV)sensing technology to acquire low-altitude images of alpine meadow surface cracks at different degrees of degradation(light,medium,and heavy degradation),and analyzed the representative metrics characterizing the degree of crack development by interpreting the crack length,length density,branch angle,and burrow(rat hole)distribution density and combining them with in situ crack width and depth ***,the correlations between the crack characterization indices and the soil and root parameters of sample plots at different degrees of degradation in the study area were analyzed using the grey relation *** results revealed that with the increase of degradation,the physical and chemical properties of soil and the mechanical properties of root-soil composite changed significantly,the vegetation coverage reduced,and the root system aggregated in the surface layer of alpine *** the degree of degradation increased,the fracture morphology developed from"linear"to"dendritic",and eventually to a complex and irregular"polygonal"*** crack length,width,depth,and length density were identified as the crack char

关键词： alpine meadow grassland degradation grassland cracks crack characterization index crack morphology root length density grey relation analysis

Broadband low-frequency sound absorption of multifunctional composite metastructure

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Science China(Technological Sciences) 2025年第2期68卷 114-124页

作者： Yilong YANG Shanshan liu Yan LI Tong GAO Yongdong PAN Yong LI yabin JIN School of Aerospace Engineering and Applied Mechanics Tongji UniversityShanghai 200092China State International Joint Research Center of Aerospace Design and Additive Manufacturing Northwestern Polytechnical UniversityXi’an 710072China Institute of Acoustics School of Physics Science and EngineeringTongji UniversityShanghai 200092China Shanghai Key Laboratory of Intelligent Sensing and Detection Technology School of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237China Shanghai Institute of Aircraft Mechanics and Control Shanghai 200092China

In this study,we fabricated multifunctional metastructures from carbon fiber-reinforced plastic composites using additive manufacturing *** metastructures are characterized by their lightweight,load-bearing capacity,and broadband low-frequency sound absorption *** metastructure consists of 36 unit cells,and non-local coupling mechanism was considered for designing the sound absorption *** developed an acoustic impedance theory tailored for the metastructure,facilitating an analysis of thermal and viscous dissipation *** is proven theoretically and experimentally that the proposed composite metastructure can achieve a noise reduction with an average sound absorption coefficient greater than 0.9 across frequencies in the rage of 330-1500 *** also studied the metastructure’s quasi-static and cyclic compression performance,confirming its efficient absorption capabilities after cyclic *** proposed design and additive manufacturing method for composite metastructures provides a novel pathway for creating lightweight,multifunctional structures with diverse applications,such as aerospace engineering.

关键词： composite metastructure broadband sound absorption additive manufacturing

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