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Exploration of playa surface crusts in Qehan Lake, China through field investigation and wind tunnel experiments

Journal of Arid Land 2023年第5期15卷 491-507页

作者： liu dongwei HAN Lijing KOU Zihan GAO Xinyu WANG Jingjing School of Ecology and Environment Inner Mongolia UniversityHohhot 010021China College of Geography and Remote Sensing Sciences Xinjiang UniversityUrumqi 830017China

Globally,many lakes are drying up,leaving exposed lakebeds where wind erosion releases dust and sand rich in salt and harmful heavy metals into the atmosphere.Therefore,understanding the characteristics and spatial distribution of playa surface crusts is important to recognize the manifestation of salt dust storms.The objective of this study was to explore the playa surface crust types as well as their spatial distribution and evolution of Qehan Lake in Inner Mongolia Autonomous Region,China to understand the salt dust release potential of different types of playa surface crusts.Various crust characteristics were investigated by field sampling in Qehan Lake,and playa surface crusts were further divided into five types:vegetated areas,salt crusts,clay flats,curly crusts,and margins.It should be noted that curly crusts were distributed in clay flats and covered only a small area in Qehan Lake.The spatial distribution characteristics of playa surface crust types were obtained by supervised classification of remote sensing images,and the salt dust release potential of crusts was explored by the wind tunnel experiments.The field investigation of Qehan Lake revealed that playa surface crust types had a circum-lake band distribution from the inside to the outside of this lake,which were successively vegetated areas,clay flats,salt crusts,and margins.The spatial distribution patterns of playa surface crust types were mainly controlled by the hydrodynamics of the playa,soil texture,and groundwater.There was a significant negative correlation between crust thickness and electrical conductivity.The results of the wind tunnel experiments showed that the initial threshold of friction wind velocity for the salt dust release was higher in clay flats(0.7–0.8 m/s)than in salt crusts(0.5–0.6 m/s).Moreover,the particle leap impact processes occurring under natural conditions may reduce this threshold value.Salinity was the main factor controlling the difference in the initial threshold of friction wind velocity for the salt dust re

关键词： playa surface crust curly crusts salt crusts salt dust release wind tunnel experiments Qehan Lake

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Development of a large-scale remote sensing ecological index in arid areas and its application in the Aral Sea Basin

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Journal of Arid Land 2021年第1期13卷 40-55页

作者： WANG Jie liu dongwei MA Jiali CHENG Yingnan WANG Lixin School of Ecology and Environment Inner Mongolia UniversityHohhot 010021China

The Aral Sea Basin in Central Asia is an important geographical environment unit in the center of Eurasia.It is of great significance to the ecological protection and sustainable development of Central Asia to carry out dynamic monitoring and effective evaluation of the eco-environmental quality of the Aral Sea Basin.In this study,the arid remote sensing ecological index(ARSEI)for large-scale arid areas was developed,which coupled the information of the greenness index,the salinity index,the humidity index,the heat index,and the land degradation index of arid areas.The ARSEI was used to monitor and evaluate the eco-environmental quality of the Aral Sea Basin from 2000 to 2019.The results show that the greenness index,the humidity index and the land degradation index had a positive impact on the quality of the ecological environment in the Aral Sea Basin,while the salinity index and the heat index exerted a negative impact on the quality of the ecological environment.The eco-environmental quality of the Aral Sea Basin demonstrated a trend of initial improvement,followed by deterioration,and finally further improvement.The spatial variation of these changes was significant.From 2000 to 2019,grassland and wasteland(saline alkali land and sandy land)in the central and western parts of the basin had the worst ecological environment quality.The areas with poor ecological environment quality are mainly distributed in rivers,wetlands,and cultivated land around lakes.During the period from 2000 to 2019,except for the surrounding areas of the Aral Sea,the ecological environment quality in other areas of the Aral Sea Basin has been improved in general.The correlation coefficients between the change in the eco-environmental quality and the heat index and between the change in the eco-environmental quality and the humidity index were–0.593 and 0.524,respectively.Climate conditions and human activities have led to different combinations of heat and humidity changes in the eco-environmental quality of the Aral Sea Basin.However

关键词： eco-environmental quality arid remote sensing ecological index Moderate Resolution Imaging Spectroradiometer(MODIS) landscape changes remote sensing monitoring Central Asia

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2001一2021年内蒙古荒漠草原水分利用效率时空变化特征及影响因素研究

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干旱区地理 2024年第6期47卷 993-1003页

作者：利辉刘铁军王少慧刘东伟内蒙古大学生态与环境学院内蒙古呼和浩特010021 水利部牧区水利科学研究所内蒙古呼和浩特010020 内蒙古阴山北麓草原生态水文野外科学观测研究站内蒙古呼和浩特010020

水分利用效率(Water use efficiency,WUE)是表征水碳过程的重要指标,对研究生态脆弱区水碳耦合规律及其响应因素具有重要意义。基于总初级生产力(GPP)、蒸散发(ET)、气温、降水量和土壤水分系统分析了2001—2021年内蒙古荒漠草原WUE的... 详细信息

水分利用效率(Water use efficiency,WUE)是表征水碳过程的重要指标,对研究生态脆弱区水碳耦合规律及其响应因素具有重要意义。基于总初级生产力(GPP)、蒸散发(ET)、气温、降水量和土壤水分系统分析了2001—2021年内蒙古荒漠草原WUE的时空变化特征,讨论了影响WUE变化的因素。结果表明:(1)内蒙古荒漠草原2001—2021年WUE平均值0.877 g C·mm^(-1)·m^(-2),空间变化范围在0.35~2.42 g C·mm^(-1)·m^(-2)。(2)预测其未来变化趋势发生转变的区域占比较大(约占69.00%),这些区域WUE未来变化趋势容易逆转。(3)空间上超过60.00%研究区的WUE与降水量、ET、土壤水分呈现正相关,其中降水量与WUE正相关最为明显(正相关区域占比约91.00%,通过显著性检验P<0.05区域占比约30.00%)。(4)WUE与气温总体呈现负相关,负相关区域占比超过60.00%。(5)气候变化在内蒙古荒漠草原WUE变化中起主要作用。内蒙古荒漠草原WUE受多种因素影响,研究结果可为气候变化背景下荒漠草原地区WUE研究提供参考。

关键词：荒漠草原水分利用效率人类活动气候变化内蒙古

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柔性直流光纤电流互感器阶跃响应特性研究

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高压电器 2024年第5期60卷 140-146页

作者：刘彬邓小聘李建光刘东伟刘博阳肖浩雷军中国电力科学研究院有限公司武汉430074 北京世维通光智能科技有限公司北京100084

传统直流光纤电流互感器无法满足柔性直流输电工程的高速响应需求,因此需要研究直流光纤电流互感器的阶跃响应特性及其动态性能改善方法。文中结合直流光纤电流互感器的离散数学模型,对其动态特性进行了全面的仿真、计算和实验研究,结... 详细信息

传统直流光纤电流互感器无法满足柔性直流输电工程的高速响应需求,因此需要研究直流光纤电流互感器的阶跃响应特性及其动态性能改善方法。文中结合直流光纤电流互感器的离散数学模型,对其动态特性进行了全面的仿真、计算和实验研究,结果表明:影响直流光纤电流互感器阶跃响应特性的关键参数是渡越时间、前向通道增益、滤波器阶数和通讯延迟。搭建了直流光纤电流互感器阶跃响应测试平台,经参数优化后的直流光纤电流互感器的阶跃响应上升时间小于50μs,满足相关应用要求。

关键词：直流光纤电流互感器阶跃响应渡越时间前向通道增益滤波器阶数通讯延迟

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Coupling analysis of short-term weather and runoff in an arid lake basin of China

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Regional Sustainability 2021年第3期2卷 264-279页

作者： WANG Jie liu dongwei TIAN Songni HU Yuehong MA Jiali WANG Lixin School of Ecology and Environment Inner Mongolia UniversityHohhot010021China Inner Mongolia Key Laboratory of River and Lake Ecology Hohhot010021China Key Laboratory of Ecology and Resource Use of the Mongolian Plateau Ministry of Education of ChinaHohhot010021China

Changes in the weather will cause variations in the hydrological system.Arid areas,with fragile hydrological systems,are very sensitive to changes in the weather,so the coupling analysis of short-term weather and runoff in arid areas is of great significance.The Daihai Lake is a closed inland lake in an arid area of China.In this paper,Weather Research and Forecasting model mode-Hydrological module(WRF-HYDRO)is used to simulate the coupling of weather and hydrology in the Daihai Lake Basin.Regional optimization of WRF-HYDRO is carried out to determine the optimal parameters.The optimal WRF-HYDRO model is applied to couple the short-term weather and runoff in the Daihai Lake Basin to reproduce several rainstorm and flood events.It is found that runoff infiltration parameter(REFKDT)in WRF-HYDRO is the parameter that has the most severe effect on runoff in the Daihai Lake Basin.WRF-HYDRO can capture the rainstorm moment of the rainstorm events in the Daihai Lake Basin,especially the first rainstorm moment,and its simulation accuracy is good.WRF-HYDRO has a strong ability to capture flood peak,but there is a discrepancy between WRF-HYDRO flood peak and Soil Conservation Service Curve Number(SCS-CN)calculation result at the flood peak moment.The northern part of Zuoyun County should guard against the occurrence of flood disaster in wet season.The coupling of weatherand hydrology can not only make up for the lack of runoff data in arid basins,but also provide a basis for water resources management and disaster prevention and mitigation in the basins.

关键词： Rainfall simulation Runoff simulation WRF-HYDRO Soil Conservation Service Curve Number Flood peak Parameter calibration Daihai Lake Basin

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轮胎材料分布图CAD参数化软件开发

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橡胶科技 2024年第5期22卷 249-253页

作者：刘东伟李红卫张健刘剑美特拓(青岛)轮胎技术有限公司山东青岛266000

基于C#编程语言,使用Winform进行图形界面开发,利用轻量化的MySQL数据库进行数据存储,基于*** API处理图形的参数化生成,开发一个轮胎材料分布图CAD参数化二次开发软件,以利于更快速、准确地进行材料分布图设计,并将结果导出为CAD图纸... 详细信息

基于C#编程语言,使用Winform进行图形界面开发,利用轻量化的MySQL数据库进行数据存储,基于*** API处理图形的参数化生成,开发一个轮胎材料分布图CAD参数化二次开发软件,以利于更快速、准确地进行材料分布图设计,并将结果导出为CAD图纸文件。该软件具有数据管理模块、CAD参数化模块和数据流转模块等功能模块,可以在Windows系统中运行,可提供友好的图形界面,与常见的CAD软件界面相似,支持用户进行可视化的操作和交互。

关键词：轮胎结构设计施工设计材料分布图 CAD软件参数化

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锡林河流域滨河带湿地植物功能性状及差异研究

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生态科学 2024年第1期43卷 134-145页

作者：寇欣刘华民张景慧苑鹏云曹晓霭温璐于晓雯刘东伟王立新内蒙古大学生态与环境学院呼和浩特010021 草原生态安全省部共建协同创新中心呼和浩特010021 蒙古高原生态学与资源利用教育部重点实验室呼和浩特010021

作为河流景观重要组成部分的滨河带,是河流水体系统与相邻陆地之间的界面或生态过渡区。湿地植物及其群落在维系湿地生态系统稳定性及功能方面具有重要作用。本文通过对比锡林河流域滨河带上游、中游、下游以及放牧干扰下湿地植物20种... 详细信息

作为河流景观重要组成部分的滨河带,是河流水体系统与相邻陆地之间的界面或生态过渡区。湿地植物及其群落在维系湿地生态系统稳定性及功能方面具有重要作用。本文通过对比锡林河流域滨河带上游、中游、下游以及放牧干扰下湿地植物20种功能性状,在流域尺度上探究滨河带湿地植物功能性状对环境和放牧强度的响应,研究表明:锡林河流域滨河带不同河段湿地植物各功能性状变异系数波动范围较大,其中叶片碳含量(LCC,Leaf Carbon Concentration)变异系数最小为0.05,变异系数最大的是光合速率(Pn,Photosynthetic Rate),其值为2.64;湿地植物的结构性状与生理性状之间通过互补与替代、在功能上的平衡实现对环境的适应;湿中生草本、中生草本、旱生草本植株高度在退化样地显著低于轻微退化样地;植物株高、叶片LCC/LNC(Leaf Carbon Concentration/Leaf Nitrogen Concentration)、LNC/LPC(Leaf Nitrogen Concentratio/Leaf Phosphorus Concentration)在五种共有植物种芦苇(Phragmites australis)、扁穗草(Blysmus rufus)、鹅绒委陵菜(Potentilla anserina)、小糠草(Agrostis alba)、疗齿草(Odontites vulgaris)群落之间均存在显著差异;锡林河流域滨河带湿地植物在不同放牧梯度下,无论是在功能群水平还是植物共有种水平,对退化程度均表现出不一致的响应。

关键词：锡林河流域滨河带植物功能性状放牧干扰

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螯合中微量元素的制备方法

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磷肥与复肥 2024年第3期39卷 34-36页

作者：罗杰刘东伟冯菊李吉梅亮贤黄麦岭化工研究院有限公司

螯合中微量元素生产中螯合剂的选择尤为重要，研究不同的螯合剂对螯合中微量元素理化性质的影响；介绍一种螯合中微量元素的制备方法，并对所得螯合产品进行稳定性实验。结果表明，制备的螯合中微量元素可以在土壤浸出液中稳定存在，以... 详细信息

螯合中微量元素生产中螯合剂的选择尤为重要，研究不同的螯合剂对螯合中微量元素理化性质的影响；介绍一种螯合中微量元素的制备方法，并对所得螯合产品进行稳定性实验。结果表明，制备的螯合中微量元素可以在土壤浸出液中稳定存在，以及在较宽泛的温度范围内非常稳定，为螯合中微量元素的应用提供了参考，具有广阔的应用前景。

关键词：中微量元素螯合剂理化性质制备方法稳定性

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Discovery of GluN2A subtype-selective N-methyl-d-aspartate(NMDA)receptor ligands

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Acta Pharmaceutica Sinica B 2024年第5期14卷 1987-2005页

作者： Liyang Jiang Na liu Fabao Zhao Boshi Huang dongwei Kang Peng Zhan Xinyong liu Department of Medicinal Chemistry Key Laboratory of Chemical Biology(Ministry of Education)School of Pharmaceutical SciencesCheeloo College of MedicineShandong UniversityJinan 250012China

The N-methyl-d-aspartate(NMDA)receptors,which belong to the ionotropic Glutamate receptors,constitute a family of ligand-gated ion channels.Within the various subtypes of NMDA receptors,the GluN1/2A subtype plays a significant role in central nervous system(CNS)disorders.The present article aims to provide a comprehensive review of ligands targeting GluN2A-containing NMDA receptors,encompassing negative allosteric modulators(NAMs),positive allosteric modulators(PAMs)and competitive antagonists.Moreover,the ligands’structure–activity relationships(SARs)and the binding models of representative ligands are also discussed,providing valuable insights for the clinical rational design of effective drugs targeting CNS diseases.

关键词： NMDA receptors GluN2A subtype Subtype-selective ligands SARs Protein ligand interactions

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Retrospective study of mycophenolate mofetil treatment in IgA nephropathy with proliferative pathological phenotype

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Chinese Medical Journal 2014年第1期127卷 102-108页

作者： Liang Yan Zhang Junjun liu dongwei Quan Songxia Xing Guolan liu Zhangsuo Department of Nephrology First Affiliated Hospital of Zhengzhou University Research Institute of Nephrology Zhengzhou UniversityZhengzhou Henan 450052 China

Background Mycophenolate mofetil （MMF） and cyclophosphamide （CTX） are widely used in treating various kidney diseases.However,whether they are effective and which one is better for treating IgA nephropathy patients with proliferative pathological phenotype in renal diseases,such as endocapillary proliferation,cellular crescents,and/or capillary loops fibrinoid necrosis is still unknown.We,therefore,initiated a study to compare the effects of MMF and CTX in treating IgA nephropathy with the above pathological lesions.Methods One hundred and nineteen patients with IgA nephropathy who had at least one of the three aforementioned lesions were enrolled.All patients were treated with prednisone; 48 patients received prednisone only （Pred group）,40 received MMF and prednisone （MMF ＋ Pred group）,and 31 were treated with CTX and prednisone （CTX ＋ Pred group）.The median time of follow-up was 30 months （maximum：96 months）.The primary endpoint was defined as renal survival.The incidence of remission of proteinuria was the secondary endpoint.Results Serum creatinine in all groups declined significantly at different follow-up times （P=0.002）,and the differences among the three groups were significant （P＜0.001）.At 24 months of follow-up,the decline rates were 12.35％,32.95％,and 24.14％ in the Pred,MMF ＋ Pred,and CTX ＋ Pred groups respectively.For urine protein excretion,the decline rates were 49.12％（Pred）,73.67％（MMF ＋ Pred）,and 63.53％（CTX ＋ Pred） respectively at 24 months of follow-up.The differences among the three groups were not significant （P=0.714）.Renal survival （the primary endpoint） was significantly different （P=0.027）; however,the sencondary endpoint was similar for all the three groups （P=0.100）.Conclusions For IgA nephropathy patients with endocapillary proliferation,cellular crescents,and/or fibrinoid necrosis of capillary loops,prednisone combined with MMF was more effective in lowering the serum creatinine than with CTX.Combined MMF and orednisone treatment led to a better renal survival compared to that of pred

关键词： mycophenolate mofetil IgA nephropathy endocapillary proliferation cyclophosphamide cellular crescents proteinuria

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