检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

加热-冷却过程中花岗岩细观热破裂机制

岩土工程学报 2024年第10期46卷 2138-2147页

作者：王飞邹岩琳庞瑞何本国范立峰孟德昊刘甜甜石垚东北大学教育部深部金属矿山安全开采重点实验室辽宁沈阳110819 北京工业大学城市建设学部建筑工程学院北京100124 中煤科工开采研究院有限公司巷道研究分院北京100013

由于高温试验设备的限制,在实验室中研究岩石真实热破裂规律通常需要依据冷却后试样的细微观结构观测结果来进行分析推断,无法获得热破裂的实时动态演化过程。为此,基于考虑温度和裂纹滑移效应的节理本构关系,构建花岗岩热力耦合UDEC晶... 详细信息

由于高温试验设备的限制,在实验室中研究岩石真实热破裂规律通常需要依据冷却后试样的细微观结构观测结果来进行分析推断,无法获得热破裂的实时动态演化过程。为此,基于考虑温度和裂纹滑移效应的节理本构关系,构建花岗岩热力耦合UDEC晶粒模型,以深入探究加热和冷却过程中花岗岩的实时热破裂行为。研究发现,在加热状态下,花岗岩热诱导微裂纹在75℃左右开始萌生,随着温度的升高,微裂纹数量在α→β石英相变温度附近快速达到峰值,但微裂纹密度在600℃降温到25℃的冷却过程中并没有明显变化。虽然冷却效应引起的裂纹数量变化可以忽略不计,但会导致裂纹开度的增加或减少。在加热过程中,微裂纹的萌生主要是由于相邻晶粒的热膨胀不同导致局部应力累积造成的。而石英高温相变引起的细微观结构变化可以增强不同晶粒之间的相互作用,导致晶粒尺度上的压缩和剪切运动加剧,使得热应力裂纹继续变形拓展。在冷却过程中,由于加热过程中热破裂导致的细微观应力释放和冷却效应导致的不同矿物晶体收缩,使得微裂纹的数量虽然不变,但其形态却能发生较为明显的变化,从而使得冷却后花岗岩的宏观应力-应变行为受到很大影响。基于离散元数值模拟对花岗岩热力耦合试验结果作出了细微观阐释,揭示了加热和冷却过程中花岗岩的实时热破裂机制,进一步加深了对高温岩石热力耦合规律的理解。

关键词：花岗岩晶粒模型实时高温热破裂

Single-cell omics:experimental workflow,data analyses and applications

在线全文

学校读者我要写书评

暂无评论

Science China Life Sciences 2024年

作者： Fengying Sun Haoyan Li Dongqing Sun Shaliu Fu Lei Gu Xin Shao Qinqin Wang Xin Dong Bin Duan Feiyang Xing Jun Wu Minmin Xiao fangqing Zhao Jing-Dong J.Han Qi Liu Xiaohui fan Chen Li Chenfei Wang Tieliu shi Center for Bioinformatics and Computational Biology Shanghai Key Laboratory of Regulatory Biology the Institute of Biomedical Sciences and School of Life Sciences East China Normal University Beijing Institutes of Life Science Chinese Academy of Sciences Peking-Tsinghua Center for Life Sciences Academy for Advanced Interdisciplinary Studies Center for Quantitative Biology (CQB) Peking University Zhejiang Key Laboratory of Precision Diagnosis and Therapy for Major Gynecological Diseases Women’s Hospital Zhejiang University School of Medicine Key Laboratory of Advanced Theory and Application in Statistics and Data Science-MOE School of Statistics East China Normal University Shanghai 200062 China Department of Clinical Laboratory the Affiliated Wuhu Hospital of East China Normal University (The Second People's Hospital of Wuhu City) Pharmaceutical Informatics Institute College of Pharmaceutical Sciences Zhejiang University Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration (Tongji University) Ministry of Education Orthopaedic Department Tongji Hospital Bioinformatics Department School of Life Sciences and Technology Tongji University Frontier Science Center for Stem Cells School of Life Sciences and Technology Tongji University Translational Medical Center for Stem Cell Therapy and Institute for Regenerative Medicine Shanghai East Hospital Bioinformatics Department School of Life Sciences and Technology Tongji University Research Institute of Intelligent Computing Zhejiang Lab Shanghai Research Institute for Intelligent Autonomous Systems Center for Single-cell Omics School of Public Health Shanghai Jiao Tong University School of Medicine National Key Laboratory of Chinese Medicine Modernization Innovation Center of Yangtze River Delta Zhejiang University

Cells are the fundamental units of biological systems and exhibit unique development trajectories and molecular features. Our exploration of how the genomes orchestrate the formation and maintenance of each cell, and control the cellular phenotypes of various organismsis, is both captivating and intricate. Since the inception of the first single-cell RNA technology, technologies related to single-cell sequencing have experienced rapid advancements in recent years. These technologies have expanded horizontally to include single-cell genome, epigenome,proteome, and metabolome, while vertically, they have progressed to integrate multiple omics data and incorporate additional information such as spatial scRNA-seq and CRISPR screening. Single-cell omics represent a groundbreaking advancement in the biomedical field,offering profound insights into the understanding of complex diseases, including cancers. Here, we comprehensively summarize recent advances in single-cell omics technologies, with a specific focus on the methodology section. This overview aims to guide researchers in selecting appropriate methods for single-cell sequencing and related data analysis.

关键词：

考虑充电站可调潜力的虚拟惯性功率补偿控制策略

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

电力系统自动化 2024年第3期48卷 73-81页

作者：施兴烨柯松张帆唐建林梁莉莉杨军交直流智能配电网湖北省工程中心湖北省武汉市430072 武汉大学电气与自动化学院湖北省武汉市430072 南方电网科学研究院有限责任公司广东省广州市510663 广东省电网智能量测与先进计量企业重点实验室广东省广州市510663 广东电网有限责任公司肇庆供电局广东省肇庆市526060

针对微电网因可再生能源接入导致惯量不足问题,提出了一种协同可再生能源发电的充电站惯性功率控制策略。首先,考虑到电动汽车具有良好的柔性调控潜力,在充电站层面将其等效为广义储能为控制器提供功率响应能力。接着,借鉴虚拟同步机的... 详细信息

针对微电网因可再生能源接入导致惯量不足问题,提出了一种协同可再生能源发电的充电站惯性功率控制策略。首先,考虑到电动汽车具有良好的柔性调控潜力,在充电站层面将其等效为广义储能为控制器提供功率响应能力。接着,借鉴虚拟同步机的转子运行特性,提出了虚拟惯性功率补偿控制策略,并配合可再生能源发电提供频率支撑。最后,在MATLAB/Simulink中搭建了相应的仿真模型进行验证。仿真结果表明,所提出的虚拟惯性功率补偿控制策略能有效利用充电站调控潜力向系统提供惯性支撑功率,提高系统的频率稳定性。

关键词：可再生能源惯量电动汽车储能虚拟同步机

基于反馈线性化的广义预测控制机械臂轨迹跟踪算法

在线全文

学校读者我要写书评

暂无评论

西北工业大学学报 2024年第2期42卷 368-376页

作者：史国庆程嘉毅张建东杨啟明吴勇武凡西北工业大学电子信息学院陕西西安710072 成都飞机设计研究所四川成都610041

分析了机械臂轨迹跟踪控制问题的特点,建立了二自由度机械臂动力学模型。为解决广义预测控制(generalized predictive control,GPC)算法难以适用于非线性系统的问题,在现有的GPC算法基础上,设计了基于反馈线性化的广义预测控制(feedback... 详细信息

分析了机械臂轨迹跟踪控制问题的特点,建立了二自由度机械臂动力学模型。为解决广义预测控制(generalized predictive control,GPC)算法难以适用于非线性系统的问题,在现有的GPC算法基础上,设计了基于反馈线性化的广义预测控制(feedback linearization-generalized predictive control,FL-GPC)算法框架,即底层为线性系统预测控制,非线性项使用预估值来进行代替,高层为迭代修正预估量,使用迭代计算的方式对非线性项进行预估。使用FL-GPC算法对二自由度机械臂的静态、动态轨迹跟踪任务进行了仿真。仿真结果表明,算法可以进行有效的机械臂轨迹跟踪控制。

关键词：轨迹跟踪非线性系统广义预测控制反馈线性化

Exploring Antarctic subglacial lakes with RECoverable Autonomous Sonde(RECAS):Design and first field tests

在线全文

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2024年第6期67卷 1866-1878页

作者： SUN YouHong PAVEL Talalay LI YuanSheng YU HaiBin WANG DongLiang LI GuoPing XU LiPing GONG Da WANG JiXin WANG JianHua WANG Ting ZHANG Nan WANG ZhiGang CHEN YanJi LIU YunChen LI YaZhou PENG shiLin shi JianGuang AN ChunLei GE Qun XU Jing NI XiaoKang CUI QiFeng JIANG Qiang MIKHAIL Sysoev Yang Yang WANG RuSheng WEI XianZhe WANG Yu ZHU TianXin DENG ZhiPeng ALEXEY Markov LI Bing fan XiaoPeng Polar Research Center Jilin UniversityChangchun130000China School of Engineering and Technology China University of GeosciencesBeijing100083China Polar Research Institute of China Shanghai200120China College of Electronics and Information Hangzhou Dianzi UniversityHangzhou310018China Aerospace System Engineering Shanghai Shanghai201109China Nanjing Institute of Astronomical Optics&Technology National Astronomical ObservatoriesChinese Academy of SciencesNanjing210000China National Ocean Technology Center Tianjin300000China

Conducting scientific drilling on subglacial lakes and obtaining samples of subglacial lake water holds great significance in unraveling the formation and evolution of Antarctic subglacial lakes and early Earth's life *** various approaches to access and directly sample subglacial water and sediments,clean access and exploration of subglacial lakes remain *** address this concern,Jilin University has developed the RECoverable Autonomous Sonde(RECAS)*** technology enables sampling and in-situ detection of subglacial lake water while being isolated from the surface,thus minimizing the risk of *** tests,including downward and upward drilling,long-running,remote-control,and cold-environment assessments,were conducted to validate the sonde's principle and *** the 38th Chinese National Antarctic Research Expedition,CHINARE(2021–2022 season),the RECAS prototype underwent testing on the flank region of Dalk glacier,10 km from Zhongshan Station in *** boreholes with depths of 200.3,183.2,and 133.5 m were successfully drilled,with the refrozen meltwater sealing the boreholes during the *** 600 mL of melted water samples were collected from each *** the drilling tests,all systems of the RECAS prototype performed within the expected ranges.

关键词： subglacial lake thermal drilling water sampling Antarctic autonomous sonde

在线全文

学校读者我要写书评

暂无评论

中国大规模盐穴储氢需求与挑战

岩土力学 2024年第1期45卷 1-19页

作者：杨春和王贵宾施锡林朱施杰郑铸颜刘伟范金洋中国科学院武汉岩土力学研究所岩土力学与工程国家重点实验室湖北武汉430071 中国科学院大学北京100049 重庆大学煤矿灾害动力学与控制全国重点实验室重庆400044

氢能是来源广泛且低碳清洁的能源,大力发展氢能产业是实现双碳目标和应对全球能源转型的重要举措。在氢能“制备―储存―运输―应用”全产业链中,储氢难问题长期制约着氢能产业高质量发展。盐穴储氢具有成本低、规模大、安全性高和储氢... 详细信息

氢能是来源广泛且低碳清洁的能源,大力发展氢能产业是实现双碳目标和应对全球能源转型的重要举措。在氢能“制备―储存―运输―应用”全产业链中,储氢难问题长期制约着氢能产业高质量发展。盐穴储氢具有成本低、规模大、安全性高和储氢纯度高等突出优势,是未来氢能大规模储备的重要发展方向,也是我国能源低碳转型的重大战略需求。综合调研了我国制氢产业和氢能消费现状,分析了我国盐穴储氢的需求。调研了国外利用盐穴储存天然气和氢气的技术及工程现状,总结了我国盐穴储气库发展和建设历程。对比了利用盐穴储存天然气、氦气、压缩空气和氢气的异同点,提出我国盐穴储氢面临三大科技挑战:层状盐岩氢气渗透与生化反应、盐穴储氢库井筒完整性管控、储氢库群灾变孕育与防控。研究成果明确了我国氢气储备需求的快速增长趋势和大规模盐穴储氢的重点攻关方向。

关键词：盐穴储氢层状盐岩氢岩反应井筒完整性库群灾变

在线全文

学校读者我要写书评

暂无评论

恶性青光眼的诊疗进展及新认识

眼科 2024年第3期33卷 161-168页

作者：石砚钟红钰余晓伟范志刚首都医科大学附属北京同仁医院北京同仁眼科中心眼科学与视觉科学北京市重点实验室北京100730

恶性青光眼主要病理生理机制为房水逆流并阻滞于玻璃体中,推动晶状体-虹膜隔前移导致中央和周边前房普遍变浅,伴或不伴高眼压。基于虹膜周切-部分悬韧带切除-玻璃体前界膜切开-前部玻璃体切除术(irido-zonulo-hyaloid-vitrectomy,IZHV)... 详细信息

恶性青光眼主要病理生理机制为房水逆流并阻滞于玻璃体中,推动晶状体-虹膜隔前移导致中央和周边前房普遍变浅,伴或不伴高眼压。基于虹膜周切-部分悬韧带切除-玻璃体前界膜切开-前部玻璃体切除术(irido-zonulo-hyaloid-vitrectomy,IZHV)这一治疗恶性青光眼金标准术式的推广及普及,对睫状体-悬韧带-晶状体-玻璃体前界膜-前部玻璃体组织复合体(ciliary body-zonules-crystalline lens-hyaloid-anterior vitreous complex,CZLHV)这一结构和功能异常在恶性青光眼发生发展中的作用认识逐渐深入。本文将基于这一复合体概念重新认识和理解恶性青光眼的发病机制,并阐述针对这一复合体结构和功能异常的恶性青光眼防治方案,以指导临床诊疗,改善预后。

关键词：恶性青光眼/外科学恶性青光眼/发病机制睫状体-悬韧带-晶状体-玻璃体前界膜-前部玻璃体组织复合体

Effects of desert plant communities on soil enzyme activities and soil organic carbon in the proluvial fan in the eastern foothills of the Helan Mountain in Ningxia,China

在线全文

学校读者我要写书评

暂无评论

Journal of Arid Land 2024年第5期16卷 725-737页

作者： SHEN Aihong shi Yun MI Wenbao YUE Shaoli SHE Jie ZHANG Fenghong GUO Rui HE Hongyuan WU Tao LI Hongxia ZHAO Na College of Forestry and Prataculture of Ningxia University Yinchuan 750021China School of Geography and Planning of Ningxia University Yinchuan 750021China Ningxia Hui Autonomous Region Agricultural Comprehensive Development Center Yinchuan 750002China Ningxia Helan Mountain National Nature Reserve Administration Yinchuan 750021China Yinchuan Yinxi Ecological Protection Forest Management Center Yinchuan 750002China

It is of great significance to study the effects of desert plants on soil enzyme activities and soil organic carbon(SOC)for maintaining the stability of the desert *** this study,we studied the responses of soil enzyme activities and SOC fractions(particulate organic carbon(POC)and mineral-associated organic carbon(MAOC))to five typical desert plant communities(Convolvulus tragacanthoides,Ephedra rhytidosperma,Stipa breviflora,Stipa tianschanica ***,and Salsola laricifolia communities)in the proluvial fan in the eastern foothills of the Helan Mountain in Ningxia Hui Autonomous Region,*** recorded the plant community information mainly including the plant coverage and herb and shrub species,and obtained the aboveground biomass and plant species diversity through sample surveys in late July *** samples were also collected at depths of 0–10 cm(topsoil)and 10–20 cm(subsoil)to determine the soil physicochemical properties and enzyme *** results showed that the plant coverage and aboveground biomass of *** community were significantly higher than those of ***,***,and *** *** communities(P<0.05).Soil enzyme activities varied among different plant *** the topsoil,the enzyme activities of alkaline phosphatase(ALP)andβ-1,4-glucosidas(βG)were significantly higher in *** and *** *** communities than in other plant communities(P<0.05).The topsoil had higher POC and MAOC contents than the ***,the content of POC in the topsoil was 18.17%–42.73%higher than that in the *** structural equation model(SEM)indicated that plant species diversity,soil pH,and soil water content(SWC)were the main factors influencing POC and *** soil pH inhibited the formation of POC and promoted the formation of ***,SWC stimulated POC production and hindered MAOC *** study aimed to gain insight into the effects of desert plant c

关键词： proluvial fan desert plant community soil enzyme activity particulate organic carbon mineral-associated organic carbon Helan Mountain

在线全文

学校读者我要写书评

暂无评论

磁信号检测高温合金内外壁缺陷分类研究

中国测试 2024年第2期50卷 161-166页

作者：罗炜韬胡博石文泽王少飞陈宇樊梦程虹之南昌航空大学无损检测技术教育部重点实验室江西南昌330063

为区分高温合金内外壁缺陷,采用高精度弱磁传感器对高温合金人工槽型缺陷进行检测。从有缺陷的一面检测为正面(即外壁缺陷),从另一面检测为反面(相当于内壁缺陷),发现单侧表面缺陷检测信号出现极性相反的情况,无法通过极性相反这一特征... 详细信息

为区分高温合金内外壁缺陷,采用高精度弱磁传感器对高温合金人工槽型缺陷进行检测。从有缺陷的一面检测为正面(即外壁缺陷),从另一面检测为反面(相当于内壁缺陷),发现单侧表面缺陷检测信号出现极性相反的情况,无法通过极性相反这一特征区分内外壁缺陷。针对这一现象,基于支持向量机中的分类功能,对采集到的弱磁信号进行特征提取获得面积、幅值和占宽3种特征量建立分类数据库,进行内外壁缺陷分类识别,并采用不同的核函数建立分类模型进行比较,最终发现径向基核函数分类模型正确率最高,为84.37%,且经过样本库外的试件验证后正确率仍有81.25%。结果表明该算法能够有效地对高温合金缺陷信号进行分析和辨识,具有一定的实用价值。

关键词：弱磁检测高温合金支持向量机内外壁缺陷识别

维普期刊数据库博看期刊