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Macro-mechanics and Microstructure of Nanomaterial-modified Geopolymer Concrete:A Comprehensive Review

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Journal of Wuhan University of Technology(Materials Science) 2025年第1期 204-214页

作者：王涛范向前 GAO Changsheng QU Chiyu The National Key Laboratory of water Disaster Prevention Nanjing Hydraulic Research Institute Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) School of water conservancy and Transportation Zhengzhou University

We have described in detail the effects of nano-SiO2,nano-CaCO3,carbon nanotubes,and nano-Al2O3on geopolymer concrete from the perspectives of macro mechanics and *** existing research results show that the mechanism of nano-materials on geopolymer concrete mainly includes the filling effect,nucleation effect,and bridging effect,the appropriate amount of nano-materials can be used as fillers to reduce the porosity of geopolymer concrete,and can also react with Ca（OH）2to produce C-S-H gel,thereby improving the mechanical properties of geopolymer *** optimum content of nano-SiO2is between 1.0% and 2.0%.The optimum content of nano-CaCO3is between 2.0% and 3.0%.The optimum content of carbon nanotubes is between 0.1% and 0.2%.The optimum content of nano-Al2O3is between 1.0% and 2.0%.The main problems existing in the research and application of nanomaterial-modified geopolymer concrete are summarized,which lays a foundation for the further application of nanomaterial in geopolymer concrete.

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A Dynamic Model for Simulating Atmospheric, Surface and soil water interactions in Hillslope of Loess Area Under Natural Conditions and Its Application

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Pedosphere 2001年第3期11卷 271-282页

作者： ZHANG SHUHAN KANG SHAOZHONG CAI HUANJIE and NIE GUANGYONG institute of Agricultural soil-water Engineering, Northwestern Agricultural University, Yangling 712100 (China) Inner Mongolia institute of water conservancy, Huhhot 010020 (China) institute of Agricultural soil-water Engineering Northwestern Agricultural University Inner Mongolia institute of water conservancy

The mechanism of atmospheric, surface and soil water interactions (water transformation) in hillslope under natural conditions was analyzed, and a dynamic model was developed to simulate infiltration, overland flow and soil water movement during natural rainfall in hillslope, by bringing forward concepts such. as rainfall intensity on slope and a correction coefficient of saturated soil water content for soil surface seal. Some factors, including slope angle, slope orientation and raindrop inclination, which affect the rainfall amount on slope, were taken into account while developing the dynamic model. The effect of surface seal on infiltration and water balance under a boundary condition of the second kind was also considered. Application of the model in a field experiment showed that the model simulated precisely the infiltration, overland flow and soil water movement in hillslope under natural rainfall conditions.

关键词： dynamic model hillslope infiltration soil water content water transformation

Land surface temperature retrieval for arid regions based on Landsat-8 TIRS data:a case study in Shihezi,Northwest China

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Journal of Arid Land 2014年第6期6卷 704-716页

作者： Lei YANG YunGang CAO XiaoHua ZHU ShengHe ZENG GuoJiang YANG JiangYong HE XiuChun YANG Department of Remote Sensing and Geographic Information Engineering Faculty of Geosciences and Environmental EngineeringSouthwest Jiaotong University institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences institute of farmland water conservancy and soil-fertilizer Xinjiang Academy of Agricultural and Reclamation Science institute of Agricultural Resources and Regional Planning Chinese Academy of Agricultural Sciences College of Environment and Planning Shangqiu Normal University

Scientific interest in geophysical information about land surface temperature （LST） is ever increasing, as such information provides a base for a large number of applications, including environmental and agricultural monitoring. Therefore, the research of LST retrieval has become a hot topic. Recent availability of Landsat-8 satel- lite imagery provides a new data source for LST retrieval. Hence, exploring an adaptive method with reliable ac- curacy seems to be essential. In this study, basing on features of Landsat-8 TIRS thermal infrared channels, we re-calculated parameters in the atmospheric transmittance empirical models of the existing split-window algorithm, and estimated the ground emissivity with the help of the land cover classification map of the study area. Further- more, a split-window algorithm was rebuilt by virtual of the estimation model of the updated atmospheric transmit- tance and the ground emissivity, and then a remote sensing retrieval for the LST of Shihezi city in Xinjiang Uygur autonomous region of Northwest China was conducted on the basis of this modified algorithm. Finally, precision validation of the new model was implemented by using the MODIS LST products. The results showed that the LST retrieval from Landsat-8 TIRS data based on our algorithm has a higher credibility, and the retrieved LST is more consistent with the MODIS LST products. This indicated that the modified algorithm is suitable for retrieving LST with competitive accuracy. With higher resolutions, Landsat-8 TIRS data may provide more accurate observation for LST retrieval.

关键词： thermal infrared remote sensing land surface temperature retrieval split-window algorithm Landsat-8 TIRS

Ski-jump trajectory based on take-off velocity

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Journal of Hydrodynamics 2016年第1期28卷 166-169页

作者：吴建华许准姚莉马飞 College of water conservancy and Hydropower Engineering Hohai University College of water conservancy and Ecological Engineering Nanchang Institute of Technology

The theoretical method estimating ski-jump trajectory was paid attention to and modified. The present method is based on the effects of the take-off velocity and the angle in the sensitivity analysis of parameters. The experiments are conducted for a triangular-shaped flip bucket in order to reveal the relationships between the take-off velocity and its influencing factors. The results show that, the take-off velocity has a much larger effect on the impact point than the take-off angle. The take-off velocities of both upper and lower trajectories are all functions of the approach flow Froude number, the deflector height and the deflection angle, especially, the results of the deflection angle of 25° could be directly used when this angle is larger than 25° Meanwhile, this method is checked and the maximum relative errors of both U calx and L_（calx） are 5.1% and 5.6%, respectively.

关键词： trajectory triangular-shaped flip bucket take-off velocity sensitivity analysis of parameters

Numerical investigation of the concentric annulus flow around a cylindrical body with contrasted effecting factors

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Journal of Hydrodynamics 2015年第2期27卷 273-285页

作者：张雪兰孙西欢李永业郗夏楠郭飞郑利剑 College of water Resource and Engineering Taiyuan University of Technology Shanxi conservancy Technical College Xi’an water conservancy Planning and Survey Designing institute

This paper studies the wall-bounded flow around a cylindrical at a high Reynolds numbers body in a determined computational domain, with simulations of the 3-D, turbulent concentric annulus flow in a straight pipe. Numerical results show that a reversing zone, appearing as a tongue zone with nested velocities higher than the surrounding area, exists behind the cylindrical body. The annulus space is a region of high velocity and low pressure. The zero velocity, of combined the X- velocity and the Y- velocity, exists in the cross sections and no vortex shedding is formed behind the attaching cylinders. Among all investigated effecting factors, the diameters of the attaching and the main cylinders affect the wake feature behind the cylindrical body while the main cylinder length does not affect the distribution tendency of the flow field. The diameters of the main cylinder and the pipe affect the pressure values and the distribution tendencies on the main cylinder surface. Obviously, the increase of the pipe diameter reduces the drag coefficient of the cylindrical body and the increase of the diameter of the main cylinder increases the drag coefficient greatly. The numerical investigation of the concentric annulus flow provides foundations for further improvements of the intricate flow studies.

关键词： numerical investigation concentric annulus turbulent flow contrasted effecting factors hydraulic characteristics

Transformation of Erosion Types on Loess Slope by REE Tracking

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Journal of Rare Earths 2007年第S1期25卷 67-73页

作者：申震洲刘普灵谢永生杨明义李勉连振龙 institute of soil and water Conservation Chinese Academy of Sciences and Ministry of Water Resources Yellow River institute of Hydraulic Research Yellow River Conservancy Commission

REE Tracking was adopted to study the transformation of erosion types on loess slope and the results indicated that the slope runoffs was correlated with the erosion ratios at the coefficients ranging within 0.84～0.94 and this indicated the variation tendency of erosion ratios basically agreed with the runoffs; the major erosion type is sheet erosion during the initial slope runoff generation and the sheet erosions separately accounted for 71%, 48% and 49% of the total; as rainfalls went on, the rill erosions continuously increased, indicating gradual transformation from sheet erosion into rill erosion. The examination of the origins of erosion silts revealed the relative erosion was always below 10% in the upper slope section; comparison of the relative rill erosions in different slope sections showed that rill erosions mainly originated in the section spanning from 0 to 4 m away from slope foot.

关键词： natural rainfall soil erosion transformation REE tracking rare earths

PRELIMINARY STUDY ON MECHANISM OF PLANT ROOTS TO INCREASE soil ANTISCOURIBILITY ON THE LOESS PLATEAU

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Science China Chemistry 1992年第9期35卷 1085-1092页

作者：李勇徐晓琴朱显谟 institute of Geochemistry Academia Sinica Guiyang 550002 PRC Northwest institute of soil and water Conservation Academia Sinica and Ministry of Water Conservancy Yangling 712100 PRC

The effects of the root system of trees, shrubs and grasses on the hydraulic andphysical properties of soil and their interrelation with increasing soil anti--scouribility byroots are quantitatively demonstrated in this paper for the first time. Based on the analysisof the leading factors of roots to increase the soil anti--scouribility, a mathematical modelon increasing soil anti-scouribility by roots is established. The value in application of themodel is to explain the mechanism of roots to increase the soil anti-scouribility and toevaluate the increasing effects of soil anti-scouribility by roots in different layers of soilThe calculated results of the values in soil anti--scouribility intensified by roots at variousintensities of rainfall and slopes of the model have higher precision, all of the meanmaximum deviations between the estimated and observed values being less than 1.417 s/g.

关键词： plant roots soil anti-scouribility hydraulic properties of soil mathematical model the Loess Plateau

A Siltation Simulation and Desiltation Measurement Study Downstream of the Suzhou Creek Sluice, China

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China Ocean Engineering 2013年第6期27卷 781-793页

作者：季永兴杨绯张汉云卢永金 College of water conservancy and Hydropower Engineering Hohai University Shanghai water Engineering Design and Research institute

The Suzhou Creek Sluice is currently the largest underwater plain gate in the world, with a single span of 100 m. It is located in a tidal estuary at the junction of the Huangpu River and Suzhou Creek in Shanghai, China. In this study, physical and 2D vertical mathematical models were used to investigate and distinguish the mechanism of siltation downstream of an underwater plain gate from that of other gates types. According to quantitative data obtained by site investigation and the application of the physical hydrodynamic models, it was found that the characteristics of the tidal estuary as well as the fact that the sluice span is equal to the creek width are the major reasons contributing to siltation. A possible desiltation treatment system is proposed for the underwater plain gate. The system includes selection of a suitable location that allows the determination of a reasonable top elevation of the sluice floor, reserving sufficient space under the gate to accommodate siltation, setting up a mechanical desiltation system, and flushing silt along with overflow over the top of the gate. Furthermore, on-site hydraulic silt flushing experiments and a topography survey were conducted. These results showed that the measurement system is effective, and by maintaining this scheduled operation once a month, the downstream riverbed has been maintained in a good condition.

关键词： tidal estuary underwater plain gate siltation sluice Suzhou Creek

Prediction of the Maturity of Greenhouse Grapes Based on Imaging Technology

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Plant Phenomics 2022年第1期4卷 357-370页

作者： Xinguang Wei Linlin Wu Dong Ge Mingze Yao Yikui Bai College of water conservancy Shenyang Agricultural UniversityShenyang 110866China institute of soil and water Conservation Northwest A&F University712100YanglingShaanxi ProvinceChina

To predict grape maturity in solar greenhouses,a plant phenotype-monitoring platform(Phenofix,France)was used to obtain RGB images of grapes from expansion to *** and longitudinal diameters,compactness,soluble solid content(SSC),titratable acid content,and the SSC/acid of grapes were measured and *** color values(R,G,B,H,S,andI)of the grape skin were determined and subjected to a back-propagation neural network algorithm(BPNN)to predict grape maturity.

关键词： maturity greenhouse content