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水泥乳化沥青砂浆微观结构演变规律研究

硅酸盐通报 2024年第7期43卷 2383-2392页

作者：金珊珊杨媛徐增淼张扬李响杨柯楠湛伟男北京建筑大学土木与交通工程学院北京100044 北京市城市交通基础设施建设工程技术研究中心北京100044

通过EDS、SEM、NMR等试验方法,从微观形貌、水化产物、元素分布、孔隙特征等多角度对多模态数据进行深度融合分析,定性与定量地研究了水泥乳化沥青(CA)砂浆微观结构随沥灰比(A/C)和龄期的演变规律。结果表明,随着A/C增大,CA砂浆由以水... 详细信息

通过EDS、SEM、NMR等试验方法,从微观形貌、水化产物、元素分布、孔隙特征等多角度对多模态数据进行深度融合分析,定性与定量地研究了水泥乳化沥青(CA)砂浆微观结构随沥灰比(A/C)和龄期的演变规律。结果表明,随着A/C增大,CA砂浆由以水泥水化产物为连续相、沥青为分散相的空间结构,转变为以沥青为连续相、水泥水化产物为分散相的疏松多孔空间结构。水泥颗粒和水化产物被沥青裹覆,严重影响了孔隙结构的发育,总孔隙率、最可几孔径逐渐增大,凝胶孔、过渡孔数量减少,大孔数量增多。随着龄期增加,水泥水化产物增多,原本较大的孔隙被分隔为较小孔隙,总孔隙率降低,大孔及毛细孔数量减少,凝胶孔及过渡孔增多,孔隙结构逐渐密实。

关键词：水泥乳化沥青砂浆沥灰比养护龄期微观形貌孔隙结构演变规律

220kV变压器中压侧中性点经小电抗接地的运行分析

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农村电气化 2024年第1期 25-27页

作者：秦彬杨克难潘振东闫存恒侯靖岩张海宾陈琳国网北京市电力公司检修分公司北京丰台100068

北京电网分区运行,其中枢纽站的接地方式关系整个电网运行,K分区中的A变电站采用220 kV变压器中压侧中性点经小电抗接地的运行方式。分析了该分区的主变中性点接地情况、A变电站的等值网络,同时计算了A变电站的短路容量、不同主变并列... 详细信息

北京电网分区运行,其中枢纽站的接地方式关系整个电网运行,K分区中的A变电站采用220 kV变压器中压侧中性点经小电抗接地的运行方式。分析了该分区的主变中性点接地情况、A变电站的等值网络,同时计算了A变电站的短路容量、不同主变并列运行时的单相短路电流,计算表明,中性点经小电抗接地后可降低其单相短路电流,满足设备热稳定性要求。同时提出中性点小电抗投运后对现场运行、倒闸操作的要求。

关键词：电网中性点接地方式变压器等值网络分析短路电流计算

Dynamic Forecasting of Traffic Event Duration in Istanbul:A Classification Approach with Real-Time Data Integration

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Computers, Materials & Continua 2024年第8期80卷 2259-2281页

作者： Mesut Ulu Yusuf Sait Türkan kenan Menguc Ersin Namlı Tarık Kucukdeniz Occupational Health and Safety Department Bandirma Onyedi Eylul UniversityBalikesir10200Türkiye Department of Industrial Engineering Istanbul University-CerrahpasaIstanbul34320Türkiye Department of Industrial Engineering Istanbul Technical UniversityIstanbul34467Türkiye

Today,urban traffic,growing populations,and dense transportation networks are contributing to an increase in traffic *** incidents include traffic accidents,vehicle breakdowns,fires,and traffic disputes,resulting in long waiting times,high carbon emissions,and other undesirable *** is vital to estimate incident response times quickly and accurately after traffic incidents occur for the success of incident-related planning and response *** study presents a model for forecasting the traffic incident duration of traffic events with high *** proposed model goes through a 4-stage process using various features to predict the duration of four different traffic events and presents a feature reduction approach to enable real-time data collection and *** the first stage,the dataset consisting of 24,431 data points and 75 variables is prepared by data collection,merging,missing data processing and data *** the second stage,models such as Decision Trees(DT),K-Nearest Neighbour(KNN),Random Forest(RF)and Support Vector Machines(SVM)are used and hyperparameter optimisation is performed with *** the third stage,feature selection and reduction are performed and real-time data are *** the last stage,model performance with 14 variables is evaluated with metrics such as accuracy,precision,recall,F1-score,MCC,confusion matrix and *** RF model outperforms other models with an accuracy of 98.5%.The study’s prediction results demonstrate that the proposed dynamic prediction model can achieve a high level of success.

关键词： Traffic event duration forecasting machine learning feature reduction shapley additive explanations(SHAP)

Integrated Stratigraphy and Mineralogy of the Doushantuo Formation in Weng’an,South China,and Implications for Ediacaran Phosphogenesis

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Journal of Earth Science 2024年第2期35卷 476-503页

作者： Liangxuan Jiao Zhenbing She Dominic Papineau Yaguan Zhang Matthew S.Dodd kenan Cao Qun Chen Guoyong Chen State Key Laboratory of Biogeology and Environmental Geology China University of GeosciencesWuhan430078China School of Earth Sciences China University of GeosciencesWuhan430047China London Centre for Nanotechnology University College London17-19 Gordon StreetLondonWC1E 6BTUK Department of Earth Sciences University College LondonLondonWC1E 6BTUK Centre for Planetary Science University College London and Birkbeck CollegeLondonWC1E 7HXUK Innovation Center of Ore Resources Exploration Technology in the Region of Bedrock Ministry of Natural Resources of People’s Republic of China’Guiyang550000China Guizhou Bureau of Geology and Mineral Exploration and Development Guiyang550000China

The Ediacaran–Cambrian Phosphogenic Episode is the Earth’s first true phosphogenic event and resulted in worldwide phosphate deposits,which occurred during the processes of the Neoproterozoic Oxygenation *** Ediacaran Doushantuo Formation(ca.635–551 Ma)of Weng’an area in central Guizhou,South China,contains two economic phosphorite beds(the Lower and Upper Phosphorite Beds).This paper presents a detailed stratigraphic,sedimentological and mineralogical study of multiple outcrop and drill core sections of the Doushantuo Formation across the Weng’an area,and identified 11 lithofacies and 4 types of phosphatic *** differences in lithofacies and grain types between the upper and lower phosphate deposits are observed,indicating that the two sets of phosphate deposits are the products of two distinct phosphogenic *** Lower Phosphorite Bed mainly consists of banded and laminated phosphorites,contains micro-oncoids formed by microbially-mediated precipitation and peloids formed by in-situ chemically oscillating reactions,indicating a biochemical and chemical enrichment of phosphorus to sediments during the Early Ediacaran *** Upper Phosphorite Bed is mainly composed of carbonaceous,massive,and stromatolitic phosphorites,contains bioclasts(phosphatized spheroidal fossils),and intraclasts formed by hydrodynamic agitation,suggesting that the major accesses of phosphorus to sediments were the remineralization of organic *** of the two economic phosphorite beds was controlled by two sea-level *** differences have also been documented in contemporaneous phosphate-bearing successions in Brazil and Mangolia,indicating a significant shift in global phosphogenic mechanism during the early and middle Ediacaran,which may be due to the changes in redox conditions in seawater,associated with the Neoproterozoic Oxygenation *** regional active P-cycle processes could produce more free oxygen,which may have contributed to the up

关键词： phosphorite lithofacies phosphatic grains phosphogenic paragenesis phosphorus cycle mineralogy

Long-term kidney transplant outcomes in Chinese patients with primary glomerulonephritis:A multicenter study in China

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Chinese Medical Journal 2024年第12期137卷 1492-1494页

作者： kenan Xie Jinsong Chen Longshan Liu Rending Wang Baoshan Gao Xiaopeng Hu Xiaotian Tang Zheng Jin Ming Zhang Yong Han Turen Song Jiqiu Wen Jiong Zhang Department of Nephrology National Clinical Research Center of Kidney DiseasesJinling HospitalNanjing University School of MedicineNanjingJiangsu 210002China Department of Organ Transplantation The First Affiliated Hospital of Sun Yat-sen UniversityGuangzhouGuangdong 510080China Department of Kidney Disease The First Affiliated HospitalCollege of MedicineZhejiang UniversityHangzhouZhejiang 310003China Department II of Urology First Hospital of Jilin UniversityChangchunJilin 130021China Department of Urology Beijing Chao-Yang HospitalCapital Medical UniversityBeijing 100020China Department of Urology The Secend Xiangya Hospital of Central South UniversityChangshaHunan 410011China Department of Renal Transplantation Hospital of NephrologyThe First Affiliated Hospital of Medical CollegeXi’an Jiaotong UniversityXi’anShaanxi 710061China Department of Liver Surgery Shanghai Jiaotong University School of Medicine Affiliated Renji HospitalShanghai 200127China Department of Respiratory and Critical Care Medicine The Eighth Medical Center of PLA General HospitalBeijing Key Laboratory of OTIRBeijing 100091China Department of Urology West China Hospital of Sichuan UniversityChengduSichuan 610041China

To the Editor:The primary cause of end-stage kidney disease(ESKD)in China is chronic glomerulonephritis(GN),which accounts for 45%of ESKD patients.[1]There is currently no nationwide large-scale study on the longterm prognosis of kidney transplantation in patients with chronic GN in *** the past decade,however,few landmark studies from populations in Europe[2,3]and the United States[4]have provided important reference data for this ***,we propose to conduct a nationwide multicenter retrospective study,which was launched by the National Clinical Research Center of Kidney Diseases,Jinling Hospital,Nanjing University School of Medicine,from 2017 to 2020.

关键词： nationwide patients glomerulonephritis

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水泥乳化沥青砂浆性能研究现状

材料导报 2021年第S2期35卷 145-149,157页

作者：杨柯楠金珊珊北京建筑大学土木与交通工程学院北京100044 北京未来城市设计高精尖创新中心北京100044

水泥乳化沥青砂浆(简称CA砂浆)是无砟轨道的重要层位,近年来关于CA砂浆的研究与应用成为行业热点。通过梳理现有研究成果发现,目前国内外关于CA砂浆的研究主要集中在配合比设计、静动态力学性能、微观结构分析和耐久性等四个方面,形成... 详细信息

水泥乳化沥青砂浆(简称CA砂浆)是无砟轨道的重要层位,近年来关于CA砂浆的研究与应用成为行业热点。通过梳理现有研究成果发现,目前国内外关于CA砂浆的研究主要集中在配合比设计、静动态力学性能、微观结构分析和耐久性等四个方面,形成了基本完善的配合比设计方法,在原材料对力学性能和耐久性的影响规律方面有了基本了解,未来在动态力学性能、宏微观关系及耐久性方面仍需要进一步开展相关研究,以提高CA砂浆的使用性能。

关键词：水泥乳化沥青砂浆配合比力学性能微观结构耐久性

基于事件触发队形优化的多四旋翼无人机协同吊挂运输系统控制

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工程科学学报 2024年第9期46卷 1535-1543页

作者：花翔宇陈谋雍可南刘伟南京航空航天大学自动化学院南京210016

无人机吊挂运输系统控制是近年无人机飞行控制方法与工程应用的热点研究之一.本文提出了一种基于事件触发队形优化的多四旋翼吊挂运输系统控制方法,在实现负载运输的同时,通过动态调整无人机集群队形降低无人机功耗.根据负载的期望受力... 详细信息

无人机吊挂运输系统控制是近年无人机飞行控制方法与工程应用的热点研究之一.本文提出了一种基于事件触发队形优化的多四旋翼吊挂运输系统控制方法,在实现负载运输的同时,通过动态调整无人机集群队形降低无人机功耗.根据负载的期望受力,通过构建优化算法滚动求解四旋翼集群当前时刻下的最优队形,并利用事件触发机制降低优化问题求解计算量.进而,采用反步法设计协同飞行控制律,并通过李雅普诺夫方法证明了闭环系统的稳定性,以及有限时间内事件触发次数的有界性.最后,通过数值仿真验证了所提出控制方法的有效性.

关键词：协同吊挂运输系统队形优化事件触发四旋翼飞行控制

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一种基于潮流追踪的电力系统无功控制分区方法

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电力系统自动化 2013年第9期37卷 29-33,122页

作者：宫一玉吴浩杨克难浙江大学电气工程学院浙江省杭州市310027 北京市电力公司北京市100031

提出了一种基于潮流追踪和凝聚算法的电力系统无功控制分区方法。该方法通过无功潮流追踪,确定无功源节点对各个节点无功输入的贡献比例,以此量化系统节点之间的无功耦合程度。在此基础上,定义了节点之间的距离,进而采用凝聚算法对系统... 详细信息

提出了一种基于潮流追踪和凝聚算法的电力系统无功控制分区方法。该方法通过无功潮流追踪,确定无功源节点对各个节点无功输入的贡献比例,以此量化系统节点之间的无功耦合程度。在此基础上,定义了节点之间的距离,进而采用凝聚算法对系统所有节点进行聚合,并确定最优分区数目。IEEE 39节点和IEEE 118节点系统的分析计算验证了所述方法的有效性。所得无功控制分区能使分区内部的无功功率基本平衡,且能随系统运行条件的变化而变化。所提分区方法计算便捷,在实际系统中具有一定的应用价值。

关键词：无功控制分区潮流追踪凝聚算法无功电压控制

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忍冬果实谱效关系研究

中华中医药学刊 2022年第7期40卷 114-117,I0022-I0024页

作者：杨柯楠韩燕雨孙启慧张芳邓志鹏刘谦李静山东中医药大学山东济南250000 北京中医药大学北京102488

目的采用高效液相色谱法(HPLC)建立忍冬果实的指纹图谱,并研究其抑菌活性的谱-效关系。方法建立忍冬果实不同发育期的HPLC指纹图谱,采用二倍稀释法考察忍冬果实对金黄色葡萄球菌、大肠杆菌、变形杆菌及铜绿假单胞菌的抑制作用,采用偏最... 详细信息

目的采用高效液相色谱法(HPLC)建立忍冬果实的指纹图谱,并研究其抑菌活性的谱-效关系。方法建立忍冬果实不同发育期的HPLC指纹图谱,采用二倍稀释法考察忍冬果实对金黄色葡萄球菌、大肠杆菌、变形杆菌及铜绿假单胞菌的抑制作用,采用偏最小二乘回归分析法(PLSR)分析谱-效关系。结果10批不同发育期的忍冬果实有26个共有峰,提取5个主成分累计方差贡献率为96.007%。结论成功建立忍冬果实不同发育期的HPLC指纹图谱和不同发育期的忍冬果实与其抑菌作用的谱-效关系,发现绿原酸、隐绿原酸、咖啡酸为潜在药效物质,为其资源开发及质量控制提供了依据。

关键词：忍冬果实抑菌活性 HPLC 谱效关系