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Responses of runoff to changes in climate and human activities in the liuhe River Basin, China

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Journal of Arid Land 2024年第8期16卷 1023-1043页

作者： li mingqian WANG He DU Wei GU Hongbiao ZHOU Fanchao CHI Baoming School of Ecology and Environment Institute of Disaster PreventionLangfang 065201China Hebei Key Laboratory of Resource and Environmental Disaster Mechanism and Risk Monitoring Sanhe 065201China Suzhou Qianxing Environmental Engineering Co. Ltd.Suzhou 215000China College of Transportation Engineering Nanjing Tech UniversityNanjing 210000China Tianjin North China Geological Exploration General Institute Tianjin 300000China

Since the 1950s,numerous soil and water conservation measures have been implemented to control severe soil erosion in the liuhe River Basin(LRB),*** these measures have protected the upstream soil and water ecological environment,they have led to a sharp reduction in the downstream flow and the deterioration of the river ecological ***,it is important to evaluate the impact of soil and water conservation measures on hydrological processes to assess long-term runoff *** the Soil and Water Assessment Tool(SWAT)models and sensitivity analyses based on the Budyko hypothesis,this study quantitatively evaluated the effects of climate change,direct water withdrawal,and soil and water conservation measures on runoff in the LRB during different periods,including different responses to runoff discharge,hydrological regime,and flood *** runoff series were divided into a baseline period(1956-1969)and two altered periods,i.e.,period 1(1970-1999)and period 2(2000-2020).Human activities were the main cause of the decrease in runoff during the altered periods,contributing 86.03%(-29.61 mm),while the contribution of climate change was only 13.70%(-4.70 mm).The impact of climate change manifests as a decrease in flood volume caused by a reduction in precipitation during the flood *** of two flood cases indicated a 66.00%-84.00%reduction in basin runoff capacity due to soil and water conservation measures in the upstream *** and water conservation measures reduced the peak flow and total flood volume in the upstream runoff area by 77.98%and 55.16%,respectively,even with nearly double the *** runoff coefficient in the reservoir area without soil and water conservation measures was 4.0 times that in the conservation *** results contribute to the re-evaluation of soil and water conservation hydrological effects and provide important guidance for water resource planning and water conservation policy formu

关键词： runoff soil and water conservation climate variability flood human activities liuhe River Basin

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加强涉外法治建设的时代意义与实践路径

当代世界 2024年第3期 42-47页

作者：李明倩华东政法大学涉外法治研究院

加强涉外法治建设是推动构建人类命运共同体和高质量共建“一带一路”的重要举措,也是当前严峻复杂的国际形势下维护中国国家利益和人民利益的现实选择。中国涉外法治建设成就显著,重点领域涉外立法不断推进,涉外执法司法合作水平明显提... 详细信息

加强涉外法治建设是推动构建人类命运共同体和高质量共建“一带一路”的重要举措,也是当前严峻复杂的国际形势下维护中国国家利益和人民利益的现实选择。中国涉外法治建设成就显著,重点领域涉外立法不断推进,涉外执法司法合作水平明显提升,涉外法治人才培养扎实开展,但也存在立法缺乏系统性与协同性、执法司法能力受限等短板。推动涉外法治建设,重在建立系统协同的涉外立法体系,提升涉外执法司法能力,创新涉外法治人才培养机制。

关键词：涉外法治建设对外关系法全球治理

深度融合信息技术,书写语文阅读课堂精彩篇章

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科教文汇 2024年第3期 151-154页

作者：李明乾甘肃省古浪县新井中心小学甘肃武威733100

随着现代信息技术的发展,信息技术在教育教学的应用赋予了课堂多元化的色彩,丰富的课堂内容依托信息技术展现在学生眼前,能给学生以富足的感受和更强的启发。在新课改背景下,小学语文教学在实施新目标、新要求的过程中,面临着许多问题... 详细信息

随着现代信息技术的发展,信息技术在教育教学的应用赋予了课堂多元化的色彩,丰富的课堂内容依托信息技术展现在学生眼前,能给学生以富足的感受和更强的启发。在新课改背景下,小学语文教学在实施新目标、新要求的过程中,面临着许多问题。小学语文教师可以借助信息技术,发挥其优势,释放语文课堂教学的无限可能。该文以小学语文阅读教学为例,探索并论述了依托信息技术实现更佳教学效果的教学措施,以期改进小学语文教学,促进阅读教学效果提升,提高学生的阅读素养。

关键词：小学语文阅读教学信息技术

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新形势下生态环境监测质量问题与对策

黑龙江环境通报 2024年第7期37卷 71-73页

作者：李铭乾河北省沧州生态环境监测中心河北沧州061000

在新形势下,生态环境监测的重要性凸显,直接关系到可持续发展、气候变化、公共健康和全球环境治理。然而,当前监测存在监测方案不合理、监管评价机制不健全、监测设备较为落后和监测人员素质有待提升等问题。为提高监测数据的科学性和... 详细信息

在新形势下,生态环境监测的重要性凸显,直接关系到可持续发展、气候变化、公共健康和全球环境治理。然而,当前监测存在监测方案不合理、监管评价机制不健全、监测设备较为落后和监测人员素质有待提升等问题。为提高监测数据的科学性和全面性,应采取一系列对策,包括强化监测方案的科学性和全面性、完善监管评价机制、推动监测设备更新升级、提升监测人员的专业水平、加强信息共享和协同机制,以及强化质量控制体系建设。这些对策有助于提高监测数据的可信度,确保生态环境监测的质量,为科学研究和决策提供可靠依据,促进可持续发展和全球环境治理。

关键词：新形势生态环境监测质量

Variations of widespread extreme cold and warm days in winter over China and their possible causes

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Science China Earth Sciences 2022年第2期65卷 337-350页

作者： Zhiyan ZUO mingqian li Ning AN Dong XIAO State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Department of Atmospheric and Oceanic Sciences/Institute of Atmospheric Sciences/IRDR-International Center of Excellence Fudan UniversityShanghai 200348China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044China

The two leading modes of winter surface air temperature(SAT) over China during 1961–2017 are a spatially consistent pattern and a north-south dipole pattern. Based on the two leading modes, the characteristics of the extreme cold and warm days in the two patterns, defined by the standard deviation larger than 1.28 or smaller than-1.28 in the time series of the two leading modes, are analyzed. With the increase of winter SAT during 1961–2017, the number of spatially consistent extreme cold days decreased and their occurrence was restricted to late December to early January, whereas the number of spatially consistent extreme warm days increased significantly in January and February. Global warming is associated with an increase in the spatially consistent extreme warm days and a decrease in spatially consistent extreme cold days, but has little relation to the sum of extreme cold and warm days of either the spatially consistent or north-south dipole pattern. The Siberian High(SH) is the main factor controlling the sum of spatially consistent extreme warm and cold days. The strong(weak) SH before(after) the1990 s corresponds to an increase(decrease) in the sum of the spatially consistent extreme warm and cold days. The occurrences of extreme south-cold-north-warm and extreme south-warm-north-cold days are related to the north-south difference of the *** the center of the SH is in mid-high latitudes, the extreme south-warm-north-cold(south-cold-north-warm) days occur more(less) often. During the winters of 1961–2017, the total number of extreme cold and warm days of the north-south dipole pattern changes negligibly. The North Atlantic meridional overturning circulation(AMOC) may be the main factor affecting the sum of the extreme cold and warm days of the two types of SAT pattern in China.

关键词： Surface air temperature Extreme cold days Extreme warm days Siberian High North Atlantic meridional overturning circulation

Orthotropic plate model for the vibration of multilayered molybdenum disulfide

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International Journal of Mechanical System Dynamics 2023年第4期3卷 373-382页

作者： mingqian li lifeng Wang State Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjingChina

Molecular dynamics(MD)simulation and orthotropic continuum model that considers interlayer shear are used to investigate the transverse deformation and free transverse vibration of multilayered rectangular molybdenum disulfide(MoS2).The interlayer shear effect is considered in the continuum model by considering the multilayered MoS_(2) as a continuous uniform orthotropic material.A method for obtaining mode shapes using a single thermal vibration MD simulation is *** frequencies and mode shapes predicted using the orthotropic continuum model and MD simulation agree *** mechanical problem of multilayered two‐dimensional material plate resonator can be solved easily and efficiently by using the finite element method for the orthotropic continuum model.

关键词： van der Waals 2D materials transition metal dichalcogenides molecular dynamics continuum model vibration

Enabling rechargeable li-MnO_(2) batteries using ether electrolytes

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SmartMat 2023年第5期4卷 131-138页

作者： Dawei Xia Hongpeng Gao mingqian li John Holoubek Qizhang Yan Yijie Yin Panpan Xu Zheng Chen Department of NanoEngineering University of California San DiegoLa JollaCaliforniaUSA Program of Materials Science and Engineering University of California San DiegoLa JollaCaliforniaUSA Program of Chemical Engineering University of California San DiegoLa JollaCaliforniaUSA Sustainable Power and Energy Center University of California San DiegoLa JollaCaliforniaUSA

A low-carbon future demands more affordable batteries utilizing abundant elements with sustainable end-of-life battery *** the economic and environmental advantages of li-MnO_(2)batteries,their applica-tion so far has been largely constrained to primary ***,we demonstrate that one of the major limiting factors preventing the stable cycling of li-MnO_(2)batteries,Mn dissolution,can be effectively mitigated by employing a common ether electrolyte,1 mol/L lithium bis(trifluorometha-nesulfonyl)imide(liTFSI)in 1,3-dioxane(DOL)/1,2-dimethoxyethane(DME).We discover that the suppression of this dissolution enables highly reversible cycling of the MnO_(2)cathode regardless of the synthesized phase and ***,we find that both the liPF_(6)salt and carbonate solvents present in conventional electrolytes are responsible for previous cycling *** ether electrolyte,paired with MnO_(2)cathodes is able to demonstrate stable cycling performance at various rates,even at elevated temperature such as 60℃.Our discovery not only represents a defining step in li-MnO_(2)batteries with extended life but provides design criteria of electrolytes for vast manganese-based cathodes in rechargeable batteries.

关键词： ether-based electrolytes li-MnO batteries Mn deposition Mn dissolution reuse of primary batteries

3D打印工艺参数对PLA/PTW共混物力学性能影响的研究

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中国塑料 2024年第2期38卷 70-75页

作者：马秀清劳志超李明谦韩顺涛胡楠北京化工大学机电工程学院北京100029 中国核电工程有限公司北京100840 航天特种材料及工艺技术研究所北京100074

采用3D打印中的熔融沉积成型(FDM)工艺制备了聚乳酸/乙烯-丙烯酸丁酯-甲基丙烯酸缩水甘油酯共聚物(PLA/PTW),通过单因素实验探究了3D打印工艺参数(喷头温度、打印平台温度和打印速度)对PLA/PTW共混物力学性能的影响,并在此基础上设计了... 详细信息

采用3D打印中的熔融沉积成型(FDM)工艺制备了聚乳酸/乙烯-丙烯酸丁酯-甲基丙烯酸缩水甘油酯共聚物(PLA/PTW),通过单因素实验探究了3D打印工艺参数(喷头温度、打印平台温度和打印速度)对PLA/PTW共混物力学性能的影响,并在此基础上设计了三因素三水平正交实验,优化了3D打印的工艺参数。结果表明,共混物的冲击强度和拉伸强度均随喷头温度的增加呈现先上升后下降、均随打印平台温度的增加而增加、均随打印速度的增加出现下降的趋势。各工艺参数对PLA/PTW共混物综合力学性能的影响从大到小依次为:喷头温度、打印速度、打印平台温度,且当喷头温度为210℃、打印平台温度为80℃以及打印速度为40 mm/s时,打印出的PLA/PTW共混物的综合力学性能最佳。

关键词： 3D打印聚乳酸/乙烯-丙烯酸丁酯-甲基丙烯酸缩水甘油酯共聚物力学性能

微纳层叠技术对ACM/PP热塑性弹性体性能的影响

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塑料 2024年第3期53卷 88-92,98页

作者：杨帆罗讴阳李明谦劳志超阎华马秀清北京化工大学机电工程学院北京100029

采用微纳层叠共挤出技术制备了ACM/PP热塑性硫化胶(TPV),研究了动态硫化温度、橡塑比、相容剂含量、炭黑与增塑剂含量对TPV力学性能与耐油性能的影响。结果表明,当动态硫化温度为190℃时,TPV具有较好的力学性能,拉伸强度、断裂伸长率、... 详细信息

采用微纳层叠共挤出技术制备了ACM/PP热塑性硫化胶(TPV),研究了动态硫化温度、橡塑比、相容剂含量、炭黑与增塑剂含量对TPV力学性能与耐油性能的影响。结果表明,当动态硫化温度为190℃时,TPV具有较好的力学性能,拉伸强度、断裂伸长率、硬度、压缩永久变形分别为12.83 MPa、104.67%、86.50%、50.00%;随着TPV橡塑比的增大,材料的拉伸强度、断裂伸长率、硬度、耐油性能明显降低;当相容剂PP-g-MAH(马来酸酐接枝聚丙烯)的含量为15份时,TPV的综合力学性能与耐油性能最佳;TPV的拉伸强度、压缩永久变形、硬度随炭黑含量的增加而升高,随增塑剂DOTP含量的增加而降低,TPV的耐油性随炭黑含量的增加而提高,随DOTP含量的增加而变差,TPV的断裂伸长率随炭黑与DOTP含量的增加而降低。

关键词：微纳层叠热塑性弹性体丙烯酸酯橡胶聚丙烯耐油性能