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Particle size characterization and sources of sediments in the Uzhumqin sand dunes

Journal of Mountain Science 2024年第8期21卷 2631-2645页

作者： ZHANG Hao LIU Yang DANG Xiaohong MENG Zhongju LI Shuangli gao yong Inner Mongolia Agricultural University Inner Mongolia 010018China Inner Mongolia Autonomous Region Water Resources Research Institute Hohhot 010020China

Sediment constitutes the fundamental basis for forming and evolving aeolian *** characteristics of sediment particle size offer insights into the development and evolution of sandy terrain,making their study critical to understanding aeolian geomorphology and sand *** this study,we combined high-density collection of surface sediments in the Uzhumqin sand dunes and GIS spatial analysis to analyze the particle size parameters and changes in the spatial distribution of surface sediments in this *** addition,we used an end-member analysis to identify the potential sources of the *** results showed that surface sediments in the Uzhumqin sand dunes had distinct spatial *** and coarse grain sands dominated the sediments in the dunes,and the mean grain size and the sorting coefficient generally increased along the prevailing wind direction,with high values in individual areas related to factors such as material sources and vegetation *** was strongly influenced by factors such as landform change and human activity,and spatial variability became more *** and the soil fractal dimension showed generally decreasing trends along the prevailing wind *** dune fixation,the contents of clay and powder particles in the soil increased;the mean particle size,the sorting coefficient,and the fractal dimension of the soil gradually increased,and the skewness and kurtosis gradually *** end-member analysis results indicated the existence of five end-members(EM)in the dune *** 1 was a mixed component of wind-deposited fine sands and nearby fluvial *** 2 was the main component of sediments in the study area and was the result of sorting lake sediments by wind action and by the local *** 3 may be a product of river flood *** 4 and EM 5 had coarser grain *** 4 was a lake-phase sediment product influenced by topographic and vegetation cover factors,and EM

关键词： Sediment Particle size Spatial differences End-member analysis Uzhumqin sand dunes

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Effects of grazing disturbance of spatial distribution pattern and interspecies relationship of two desert shrubs

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Journal of Forestry Research 2022年第2期33卷 507-518页

作者： Lei Zhang yong gao Jinrong Li Chao Zhang Minyu Li Zhao Hu Xiangxin Cui College of Desert Science and Engineering Inner Mongolia Agricultural UniversityHohhot 010019People’s Republic of China Institute of Water Resources for Pastoral Area of the Ministry of Water Resources Hohhot 010020People’s Republic of China Institute of Forestry Monitoring and Planning of Inner Mongolia Autonomous Region Hohhot 010020People’s Republic of China School of Soil and Water Conservation Beijing Forestry UniversityBeijing 100083People’s Republic of China

Grazing significantly affects the distribution,growth,and productivity of *** this study,we evalu-ated the effects of grazing disturbance on the spatial distri-bution patterns and interspecific relationships of two desert shrubs,Ammopiptanthus mongolicus and Sarcozygium *** types of grazing conditions were considered,including enclosed area(EA),seasonal rotational grazing area(SRGA),and grazing area(GA)(100 m×100 m),in the West Ordos Nature Reserve of Inner Mongolia,*** results showed that *** and *** populations were uniformly distributed at a small scale,and the distribution in EA and SRGA became gradually *** GA,*** population showed aggregated distribution but *** population showed random distribution at a small scale. Moreover, both A. mongolicus and S. xanthoxylon populations at the 5-7 m scale showed random distribution. At the small and intermediate scales, the two species showed positive interspecific relationships of GA. However, no interspecific relationship was noted between the two species in EA and SRGA. A significant positive relationship (P < 0.01) was noted between the two species at 2-9 m and a negative relationship (P < 0.01) at 13-17 m scales in GA. Positive relationship (P < 0.01) was noted between the two species at 6-13 m scales and a sig-nificant negative relationship (P < 0.01) at 14-24 m scales in SRGA. The two species of desert shrubs showed posi-tive interspecific relationships at the small scale, and they showed negative relationships as the interspecific compe-tition intensified in the presence of grazing disturbance. When the grazing intensity exceeds a certain threshold, the interspecific relationships become weak. Therefore, moder-ate grazing would facilitate interspecific competition and species succession, whereas excessive grazing would disrupt natural competition causing desertification ultimately.

关键词： Extending point pattern analysis Grazing Interspecific relationships Unmanned aerial vehicle(UAV)

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Auxin-brassinosteroid crosstalk:Regulating rice plant architecture and grain shape

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The Crop Journal 2024年第4期12卷 953-963页

作者： Meidi Wu Jing Zhou Qian Li Dunfan Quan Qingwen Wang yong gao Jiangsu Key Laboratory of Crop Genomics and Molecular Breeding/Key Laboratory of Plant Functional Genomics of the Ministry of Education/Jiangsu Key Laboratory of Crop Genetics and Physiology Yangzhou UniversityYangzhou 225009JiangsuChina Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops Joint International Research Laboratory of Agriculture and Agri-Product Safety of the Ministry of EducationYangzhou UniversityYangzhou 225009JiangsuChina

Rice(Oryza sativa)plant architecture and grain shape,which determine grain quality and yield,are modulatedby auxin and brassinosteroid via regulation of cell elongation and *** review the signaltransduction of these h... 详细信息

关键词： Auxin Brassinosteroid Auxin-brassinosteroid crosstalk Plant architecture Grain shape

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Elevation,bedrock exposure,land use,interbedded limestone and clastic rock,and vegetation coverage dominate the spatiotemporal variability of soil erosion in karst basin

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Journal of Mountain Science 2023年第9期20卷 2519-2535页

作者： CHEN Mei gao Jia-yong CHEN Hong-lian JING Jun LI Rui School of Karst Science Guizhou Normal UniversityGuiyang 550001China State Engineering Technology Institute for Karst Desertification Control Guiyang 550001China

Soil erosion is a prominent environmental problem in karst *** the spatiotemporal variability of soil erosion and the factors that influence soil erosion is of great significance for regional soil erosion prevention and ***,the mechanisms influencing the characteristic features of the karst basins,such as bedrock exposure and lithology,still need to be further *** study used GIS technology,the Revised Universal Soil Loss Equation model,Getis–Ord Gi*,and partial least squares regression(PLSR)to identify the dominant factors influencing soil erosion and the spatiotemporal variability of soil erosion in 31 sub-basins of the Dabang River Basin(DRB),a typical karst area of Southwest China,from 2010 to *** results indicated that soil erosion in the DRB from 2010 to 2020 was generally decreasing,the mean soil erosion in the DRB in 2010,2015 and 2020 was 18.46,16.51 and 15.29 t ha^(-1)a^(-1),*** the study period,the area of slight erosion increased by 26.39%(706.54 km^(2)),while severe erosion enlarged by 26.36 km^(2).Spatially,the DRB was primarily affected by medium and slight soil *** hot spot areas of soil erosion(key control areas)were mainly concentrated in the central and southern parts of the basin,decreasing each year,and the area of soil erosion hot pots has decreased from 43.22%to 20.60%.PLSR decoupling results show that elevation,bedrock exposure,land use type,interbedded limestone and clastic rock,and vegetation coverage were identified as the key variables affecting soil erosion,explaining 52.8%of soil erosion variability,with a high value of the Variable Importance on Projection(VIP)more than *** results can be used as a reference for comprehensive control of soil erosion and water loss in the basin.

关键词： Soil erosion Karst basin RUSLE model Spatiotemporal variability PLSR

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Effect of interaction of refractories with Ni-based superalloy on inclusions during vacuum induction melting

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International Journal of Minerals,Metallurgy and Materials 2020年第11期27卷 1551-1559页

作者： Xiao-yong gao Lin Zhang Xuan-hui Qu Xiao-wei Chen Yi-feng Luan Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China

This study documents laboratory-scale observation of the interactions between the Ni-based superalloy FGH4096 and *** different crucibles were tested—MgO,Al2O3,and MgO–*** studied the variations in the compositions of the inclusions and the alloy–crucible interface with the reaction time using scanning electron microscopy equipped with energy dispersive X-ray spectroscopy and Xray *** results showed that the MgO and MgO–spinel crucibles form MgO-containing inclusions(Al–Mg oxides and Al–Mg–Ti oxides),whereas the inclusions formed when using the Al2O3 crucible are Al2O3 and Al–Ti *** observed a new MgAl2O4 phase at the inner wall of the MgO crucible,with the alloy melted in the MgO crucible exhibiting fewer *** new phase occurred at the inner wall of the Al2O3 *** discuss the mechanism of interaction between the refractories and the Ni-based *** erosion was found to predominate in the Al2O3 crucible,whereas dissolution and chemical reactions dominated in the MgO *** reaction was observed between three crucibles and the Ti of the melt although the Ti content(3.8wt%)was higher than that of Al(2.1wt%).

关键词： FGH4096 superalloy vacuum induction melting crucible inclusion Mg/O ratio

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Algorithm Research and Real-time Simulation of Neural Network Sliding Mode Position Control

Algorithm Research and Real-time Simulation of Neural Networ...

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第25届中国控制与决策会议

作者： LI Wei ZHANG Yanyu gao yong CHAI Xiuli Institute of Image Processing and Pattern Recognition Henan University School of Computer and Information Engineering Henan University School of Automation Science and Engineering Beihang University

ISBN: (纸本)9781467355339

This paper presents a neural network sliding mode control algorithm for position control of modular robot. This method adopts BP neural network to approximate the functional relation between the sliding hyperplane and the exponential approximation rate. At the same time, the saturation function of sliding mode control algorithm is replaced by a hyperbolic tangent function to realize the boundary design method of the sliding mode control. The results of real-time simulation show that the algorithm proposed in this paper has the merits of fast response, strong robustness, and reducing the chattering of sliding mode control. This method solves the problems that conventional PID algorithm can’t solve under some circumstances, such as complicated environment, great load change, etc.

关键词： Robot control actuator sliding mode control neural network control

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SlSOM inhibits seed germination by regulating the expression of ABA/GA metabolic genes and SlABI5 in Solanum lycopersicum

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Journal of Integrative Agriculture 2015年第2期14卷 326-336页

作者： SUN Xiao-chun gao yong-feng ZHANG Ning LI Hui-rong YANG Shu-zhang LIU yong-sheng Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment/State Key Laboratory of Hydraulics and Mountain River Engineering/College of Life Science Sichuan University School of Biotechnology and Food Engineering Hefei University of Technology

SOM encodes a nucleus-localized CCCH-type zinc finger protein and negatively regulates seed germination in Arabidopsis thaliana. We have previously demonstrated that ectopic expression of Sl ABI3, an important transcription factor in abscisic acid（ABA） signaling pathway, resulted in alteration of Sl SOM expression patterns in both leaf and seed of tomato. In this study, we aimed to elucidate the function of tomato Sl SOM in regarding to seed germination and seedling development. Here, we constructed Sl SOM over-expression vector p BI121-SOM driven by Ca MV 35 S promoter, and the recombinant plasmid was incorporated into wild-type tomato by the method of Agrobacterium tumefaciens-mediated transformation. The result showed that over-expression of Sl SOM conferred enhanced responses to exogenous ABA application during seed germination and seedling development. In addition, ectopic expression of Sl SOM resulted in the alteration of expression level of ABA/GA（gibberellins） metabolic genes, such as Sl ABA1, Sl CYP707A1, Sl GA3ox2, and Sl GA2ox4, in both leaf and seed. The ABA anabolic gene Sl ABA1 and the GA catabolic gene Sl GA2ox4 were up-regulated while the ABA catabolic gene Sl CYP707A1 and the GA anabolic gene Sl GA3ox2 were down-regulated. Compared to wild type, the expression level of Sl ABI5 was increased by about 40–50% in transgenic seeds while adding exogenous ABA treatment. These results support the notion that Sl SOM inhibits seed germination by regulating ABA/GA metabolic genes and Sl ABI5 expression in Solanum lycopersicum.

关键词： tomato SOM seed germination abscisic acid

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Subpolar Gyre Index and the North Atlantic Meridional Overturning Circulation in a Coupled Climate Model

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Atmospheric and Oceanic Science Letters 2008年第1期1卷 29-32页

作者： gao yong-Qi YU Lei Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Nansen Environmental and Remote Sensing Center/Bjerknes Centre for Climate Research Bergen Norway

The subpolar gyre index (SPG), derived from the analysis of sea surface height (SSH), is proposed to be a potential indicator for the North Atlantic Meridional Overturning Circulation (AMOC) based on observation as well as the Ocean General Circulation Model (OGCM). We investigated the correspondence between the SPG and the AMOC in a coupled climate model. Our results confirm that the SPG can be used as an early indicator for the AMOC in the subtropical North Atlantic. Changes in the SPG are closely related to variations in the air-sea heat exchange in the Labrador Sea, and variations in deep water formation and southward dense water transport with the deep western boundary current (DWBC) in the North Atlantic.

关键词： subpolar gyre index North Atlantic merid-ional overturning circulation indicator

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A semantic geographical knowledge wiki system mashed up with Google Maps

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Science China(Technological Sciences) 2010年第S1期53卷 52-60页

作者： gao yong,gao Song,LI RunQiang & LIU YuInstitute of Remote Sensing and Geographical Information Systems,Peking University,Beijing 100871,China 1. Institute of Remote Sensing and Geographical Information Systems Peking University Beijing 100871 China

A wiki system is a typical Web 2.0 application that provides a bi-directional platform for users to collaborate and share much useful information ***,computers cannot well understand the wiki pages in plain *** user-generated geographical content via wiki systems cannot be manipulated properly and efficiently unless the geographical semantics is explicitly *** this paper,a geographical semantic wiki system,Geo-Wiki,is introduced to solve this ***-Wiki is a semantic geographical knowledge-sharing web system based on geographical ontologies so that computers can parse and storage the multi-source geographical ***,Geo-Wiki mashed up with map services enriches the representation and helps users to find spatial distribution patterns,and thus can serve geospatial decision-making by customizing the Google Maps APIs.

关键词： geo-ontology semantic wiki mashup Google Maps

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Change in Sea Ice Cover is Responsible for Non-Uniform Variation in Winter Temperature over East Asia

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Atmospheric and Oceanic Science Letters 2015年第6期8卷 376-382页

作者： LI Fei WANG Hui-Jun gao yong-Qi Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Climate Change Research Center Chinese Academy of Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University for Information Science and Technology Nansen Environmental and Remote Sensing Center and Bjerknes Centre for Climate Research

Observed winter(December–February)surface air temperature over East Asia(0°–60°N,100–140°E)(TEA)shows non-uniform variation during 1979–2013,with cooling and weak warming north and south of40°*** understand this,the authors perform statistical analysis(linear regression and composite)on the observed *** results suggest that reduced(increased)autumn sea ice cover in the Barents-Kara Sea(BK-ASIC)lowers(warms)TEA over northern East Asia,which is consistent with previous *** comparison,increased(decreased)winter sea ice cover in the Sea of Okhotsk(O-WSIC),warms(cools)the air over southern East *** mechanism can be described as follows:When the BK-ASIC decreases,the East Asian winter monsoon tends to be stronger with an intensified Siberian high,leading to cooling over northern East *** O-WSIC increase is associated with cold anomalies north of 50°N,altering the meridional temperature gradient between the midlatitudes and tropics,and leading to a northward shift of the East Asian jet steam in the upper *** the low atmosphere,anomalous northeasterly winds prevail north of50°N and anomalous southerly winds control the southern coast of East Asia,contributing to the weak warming over southern East *** 3 of the Community Atmosphere Model also provides evidence for the impact of increased O-WSIC on the warm southern mode of TEA.

关键词： East Asia winter temperature Arctic sea ice cover

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