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An analysis of soil composition and mechanical properties of riverbanks in a braided reach of the Lower Yellow River

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Chinese Science Bulletin 2008年第15期53卷 2400-2409页

作者： XlA JunQiang WU BaoSheng WANG YanPing zhao shougang State Key Laboratory of Hydroscience and Engineering Tsinghua University Beijing 100084 China Yellow River Institute of Hydraulic Research YRCC Zhengzhou 450003 China

The channel adjustment in a braided reach is very prominent in the fluvial processes of the Lower Yel-low River, in which the process of bank erosion plays an important role, especially during the period of clear water scouring. The process of bank erosion is closely related to soil composition and mechani-cal properties of the riverbanks. In this paper, the recent bank erosion process in a braided reach be-tween Huayuankou and Gaocun was firstly investigated after the water impoundment and sediment detention of the Xiaolangdi Reservoir, and then a field observation and indoor soil tests were con-ducted at 10 typical riverbanks in the braided reach. Through analyzing the experimental results, changes of riverbank-soil composition and mechanical properties were found, and the two real reasons causing serious bank erosion in the braided reach were identified. The following conclusions were drawn from this study: (i) the majority of riverbanks are made up of cohesive soil, and can be charac-terized by obvious vertical stratification structures of soil composition; (ii) these riverbanks are very erodible due to the lower clay-content and weak erosion-resistant strength in the bank soil, with its critical shear stress value (0.1―0.3 Pa) being much less than that of the average near-bank flow shear stress (2.0―3.0 Pa), which is one important reason causing serious bank erosion; (iii) frequent occur-rence of bank failure during flood seasons usually results from the fact that the values of shear strength parameters such as the cohesion and internal friction angle decrease with the increase of water content in riverbank soil, and the value of cohesion reduces drastically from 34 to 4 kPa with the increase of water content, which is another important reason causing serious bank erosion in the braided reach.

关键词：黄海土壤分析河堤侵蚀化学物质

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胶凝堆石料力学性能试验及本构关系特性研究

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岩土工程学报 2023年第S1期45卷 230-233,248页

作者：赵寿刚李娜何鲜峰黄河水利委员会黄河水利科学研究院河南郑州450003 水利部堤防安全与病害防治工程技术研究中心河南郑州450003

通过大型三轴试验得到了胶凝堆石料应力-应变关系曲线,分析了其力学性能,并针对关系曲线存在明显的非线性及软化特性,采用分段描述的方法建立了胶凝堆石料的本构关系,即破坏强度前考虑剪切所引起的体积变化采用双模量K-G模型描述,峰值... 详细信息

通过大型三轴试验得到了胶凝堆石料应力-应变关系曲线,分析了其力学性能,并针对关系曲线存在明显的非线性及软化特性,采用分段描述的方法建立了胶凝堆石料的本构关系,即破坏强度前考虑剪切所引起的体积变化采用双模量K-G模型描述,峰值强度后软化曲线的数学模型通过数据的回归分析和参数反演方式分析得到,各模型参数均可通过大三轴试验获取,方便可靠。

关键词：胶凝堆石料应力-应变龄期本构关系大三轴试验

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中里坪浆砌石拱坝坝体应力分析和评价

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水利水电技术 2010年第12期41卷 38-41页

作者：赵寿刚张俊霞兰雁水利部堤防安全及病害防治工程技术研究中心河南郑州450003 黄河水利科学研究院河南郑州450003

针对中里坪拱坝实际工程情况,运用多拱梁法进行了应力计算和分析,以便掌握坝体在不同荷载组合工况的应力分布状况,为大坝可行性评价及蓄水过程提供理论依据。计算结果表明:(1)中里坪拱坝的主压应力在三种组合工况下均满足规范要求,拱坝... 详细信息

针对中里坪拱坝实际工程情况,运用多拱梁法进行了应力计算和分析,以便掌握坝体在不同荷载组合工况的应力分布状况,为大坝可行性评价及蓄水过程提供理论依据。计算结果表明:(1)中里坪拱坝的主压应力在三种组合工况下均满足规范要求,拱坝结构有一定的安全裕度;(2)主拉应力也都在规范允许范围内。

关键词：浆砌石拱坝坝体应力荷载组合拱梁分载法中里坪浆砌石拱坝

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水闸侧墙与土体接合部渗透破坏过程模拟试验

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水利水电科技进展 2019年第6期39卷 75-81,94页

作者：李娜汪自力赵寿刚岳瑜素黄河水利委员会黄河水利科学研究院河南郑州450003 水利部堤防安全与病害防治工程技术研究中心河南郑州450003

为深化对穿堤涵闸土石接合部渗透破坏发展机理的认识,研发了试验装置,实现了水闸侧墙与土体接合部渗透破坏过程的室内模拟。通过对黏粒质量分数分别为4.6%、12.3%及22.6%的土体开展试验,分析了接触冲刷的破坏特征及其发生发展规律,探讨... 详细信息

为深化对穿堤涵闸土石接合部渗透破坏发展机理的认识,研发了试验装置,实现了水闸侧墙与土体接合部渗透破坏过程的室内模拟。通过对黏粒质量分数分别为4.6%、12.3%及22.6%的土体开展试验,分析了接触冲刷的破坏特征及其发生发展规律,探讨了土体性质、水力比降、接触带压实度等因素对渗透破坏的影响。试验结果表明:土石接合部接触冲刷破坏过程分为稳定渗流阶段、管涌形成发展阶段和冲蚀破坏发展阶段;土体黏粒质量分数越大、压实度越大,土体稳定时间及破坏时间越长,抗冲蚀能力越强;冲蚀量与土体黏粒质量分数、水力比降及压实度均呈现明显的反比关系;水力比降较小时,压实度对土体抗冲性能影响显著,但随着水力比降的逐渐增大,土体性质起主导作用;初始破坏阶段土体细颗粒的流失受土体性质、压实度及水力比降各因素的综合作用,表现出不同的规律性。

关键词：土石接合部接触冲刷黏粒质量分数水力比降破坏特性

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Recycling arsenic-containing bio-leaching residue after thermal treatment in cemented paste backfill:Structure modification,binder properties and environmental assessment

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2136-2147页

作者： Dengfeng zhao Shiyu Zhang Yingliang zhao Department of Mining Engineering Lyuliang UniversityLvliang 033000China School of Civil and Environmental Engineering University of Science and Technology BeijingBeijing 100083China School of Mining Engineering Taiyuan University of TechnologyTaiyuan 030024China Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong 00852China

The substantial arsenic(As)content present in arsenic-containing bio-leaching residue(ABR)presents noteworthy environ-mental challenges attributable to its inherent instability and susceptibility to *** its elevated calcium sulfate content,ABR exhibits considerable promise for industrial *** study delved into the feasibility of utilizing ABR as a source of sulfates for producing super sulfated cement(SSC),offering an innovative binder for cemented paste backfill(CPB).Thermal treatment at varying temperatures of 150,350,600,and 800℃ was employed to modify ABR’s *** investigation encompassed the examination of phase transformations and alterations in the chemical composition of As within ***,the hydration characteristics of SSC utilizing ABR,with or without thermal treatment,were studied,encompassing reaction kinetics,setting time,strength development,and *** findings revealed that thermal treatment changed the calcium sulfate structure in ABR,consequently impacting the resultant sample ***,calcination at 600℃ demonstrated optimal modification effects on both early and long-term strength *** enhanced performance can be attributed to the augmented formation of reaction products and a densified ***,the thermal treatment elicited modifications in the chemical As fractions within ABR,with limited impact on the As immobilization capacity of the prepared binders.

关键词： cemented paste backfill bio-leaching residue arsenic immobilization binder hydration calcination

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Automatic modeling algorithm of stochastic error for inertial sensors

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Control Theory and Technology 2024年第1期22卷 81-91页

作者： Luodi zhao Long zhao School of Automation Science and Electrical Engineering Beihang UniversityBeijing100191China Digital Navigation Center Beihang UniversityBeijing100191China Science and Technology on Aircraft Control Laboratory Beihang UniversityBeijing100191China

This paper proposes an automatic algorithm to determine the properties of stochastic processes and their parameters for inertial error. The proposed approach is based on a recently developed method called the generalized method of wavelet moments (GMWM), whose estimator was proven to be consistent and asymptotically normally distributed. This algorithm is suitable mainly (but not only) for the combination of several stochastic processes, where the model identification and parameter estimation are quite difficult for the traditional methods, such as the Allan variance and the power spectral density analysis. This algorithm further explores the complete stochastic error models and the candidate model ranking criterion to realize automatic model identification and determination. The best model is selected by making the trade-off between the model accuracy and the model complexity. The validation of this approach is verified by practical examples of model selection for MEMS-IMUs (micro-electro-mechanical system inertial measurement units) in varying dynamic conditions.

关键词： GMWM Stochastic process Inertial sensor Sensor calibration Error model Allan variance

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Meeting the challenges of invasive alien species

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National Science Review 2024年第3期11卷 296-298页

作者： Weijie zhao NSR news

The Xinjiang Uygur Autonomous Region of China is famous for its tomato production. Abundant sunshine, large day–night temperature difference and the abundant irrigation by snowmelt from the Tianshan Mountains produce...

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Ling-Ling Chen: RNA has its own features;don't study it as a protein

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National Science Review 2024年第2期11卷 301-305页

作者： Weijie zhao NSR

Non-coding RNA(ncRNA) has been a very active research area over the past 30 years. From small nc RNA – the discovery of RNA interference won the lead researchers the Nobel Prize, to long ncRNA(lncRNA), which has attracted much attention in recent years, various nc RNAs participate in all kinds of biological processes and show a variety of biomedical application prospects.

关键词： RNA

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用微波炉测定土含水量的比较试验

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防渗技术 2000年第3期6卷 5-10页

作者：李祯祥赵寿刚西北农林科技大学水利与建筑工程学院陕西杨凌712100 黄河水利委员会科学院工力所

对某土石坝心墙填筑土料分别用微波炉与烘干法测定其含水量 ,进行了 46 5组比较试验 ,得出了微波法含水量和烘干法含水量的关系 ,则可用微波法快速测定土的含水量 ,利用这一关系进行修正 ,然后即可把修正的结果应用于实际 ,这对加快工... 详细信息

对某土石坝心墙填筑土料分别用微波炉与烘干法测定其含水量 ,进行了 46 5组比较试验 ,得出了微波法含水量和烘干法含水量的关系 ,则可用微波法快速测定土的含水量 ,利用这一关系进行修正 ,然后即可把修正的结果应用于实际 ,这对加快工程进度又确保质量是有裨益的。

关键词：微波法烘干法含水量比较试验土料

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Giant Flexoelectric Effect in Snapping Surfaces Enhanced by Graded Stiffness

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Acta Mechanica Solida Sinica 2024年第4期37卷 528-540页

作者： Chuo zhao Department of Aeronautics Imperial College LondonSouth Kensington CampusLondonSW72AZUK

Flexoelectricity is present in nonuniformly deformed dielectric materials and has size-dependent properties, making it useful for microelectromechanical systems. Flexoelectricity is small compared to piezoelectricity;therefore, producing a large-scale flexoelectric effect is of great interest. In this paper, we explore a way to enhance the flexoelectric effect by utilizing the snap-through instability and a stiffness gradient present along the length of a curved dielectric plate. To analyze the effect of stiffness profiles on the plate, we employ numerical parameter continuation. Our analysis reveals a nonlinear relationship between the effective electromechanical coupling coefficient and the gradient of Young’s modulus. Moreover, we demonstrate that the quadratic profile is more advantageous than the linear profile. For a dielectric plate with a quadratic profile and a modulus gradient of − 0.9, the effective coefficient can reach as high as 15.74 pC/N, which is over three times the conventional coupling coefficient of piezoelectric material. This paper contributes to our understanding of the amplification of flexoelectric effects by harnessing snapping surfaces and stiffness gradient design.

关键词： Functionally graded material Flexoelectricity Numerical continuation Snap-through instability

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