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基于广义Voigt模型的半渗透边界隧道周围饱和软土固结分析

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岩土力学 2024年第7期45卷 2024-2036页

作者：谢森林胡安峰肖志荣汪美慧胡训健陈俞超浙江大学滨海和城市岩土工程研究中心浙江杭州310058 浙江大学建筑设计研究院有限公司浙江杭州310058 浙江大学平衡建筑研究中心浙江杭州310058 浙江科技学院土木与建筑工程学院浙江杭州310023 武汉大学土木建筑工程学院湖北武汉430072

引入衬砌半渗透边界条件,使用广义Voigt黏弹性模型描述隧道周围饱和软黏土的流变特性,基于Terzaghi-Rendulic理论建立以超孔隙水压力为变量的软土二维流变固结控制方程。采用保角变换和分离变量方法,得到超孔隙水压力关于时间和空间变... 详细信息

引入衬砌半渗透边界条件,使用广义Voigt黏弹性模型描述隧道周围饱和软黏土的流变特性,基于Terzaghi-Rendulic理论建立以超孔隙水压力为变量的软土二维流变固结控制方程。采用保角变换和分离变量方法,得到超孔隙水压力关于时间和空间变量的两个独立方程,依次使用Laplace变换法与部分分式展开法得到时域内超孔隙水压力消散解。将广义Voigt模型退化为已有四元件Burgers模型和五元件模型并与其对比,验证解答的可靠性。基于建立的解答,分析衬砌透水程度、Kelvin体数量、独立Newton黏壶黏滞系数、隧道埋深等因素对超孔隙水压力消散与分布的影响规律。结果表明:衬砌与土体的相对渗透系数比越大,超孔隙水压力的消散起始时间越早,消散速度越快。Kelvin体数量越多,超孔隙水压力消散越慢;独立黏壶黏滞系数越大,其产生的黏滞变形越小,超孔隙水压力消散速率越快;隧道埋深越大,土体渗流路径越长,超孔隙水压力消散越慢;当相对渗透系数比为0.01时,超孔隙水压力随着到隧道外壁距离的增大而逐渐减小,当相对渗透系数比为1.00时,超孔隙水压力随着距离的增大而出现先增大后减小的现象;随着相对渗透系数比的增加,Kelvin体数量对超孔压消散的影响越小,不同独立黏滞系数带来的超孔压消散差异逐渐减小,隧道衬砌作为土层内部新透水边界的作用越突出。

关键词：黏弹性地基半渗透边界广义Voigt模型超孔隙水压力流变固结

Spatiotemporal Variation of Water Vapor Budget over the Tibetan Plateau and Its Regulation on Precipitation

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Journal of Tropical Meteorology 2022年第2期28卷 194-206页

作者： wang hui-mei ZHAO Ping Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science and TechnologyNanjing 210044 China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081 China Institute of Tibetan Plateau&Polar Meteorology Chinese Academy of Meteorological SciencesBeijing 100081 China

The spatiotemporal variations of water vapor budget(Bt)and their relationships with local precipitation over the Tibetan Plateau(TP)are critical for understanding the characteristics of spatial distributions and evolutions of water resources over the *** on a boundary of the TP,this paper explored the spatiotemporal characteristics of Bt over the TP using the European Centre for Medium-Range Weather Forecasts interim(ERA-Interim)reanalysis *** the climatological mean,the TP is a water vapor sink throughout four seasons and the seasonal variation of Bt is closely associated with the water vapor budget at the southern boundary of the *** transient water vapor transport is quasimeridional in the mid-and high-latitude areas and plays a leading role in winter Bt but contributes little in other *** the interannual timescale,the variation of Bt is mainly determined by anomalous water vapor transports at the western and southern *** Bay of Bengal,the North Arabian Sea,and mid-latitude West Asia are the main sources of excessive water vapor for a wetter *** the southern and western boundaries,the transient water vapor budget regulates one-third to four-fifths of Bt ***,the variability of the TP Bt is closely associated with precipitation over the central-southern and southeastern parts of the TP in summer and winter,which is attributed to the combined effect of the stationary and transient water vapor *** the role of the transient water vapor transport,the linkage between the TP Bt and local precipitation is tighter.

关键词： Tibetan Plateau water vapor budget transient water vapor transport stationary water vapor transport precipitation

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GPS测绘技术在矿山地质测绘中的应用实践

世界有色金属 2024年第11期 154-156页

作者：宫倩孙宜聪王惠梅山东省地质矿产勘查开发局第五地质大队山东泰安271000

本文中对GPS测绘技术的具体内容进行论述,并说明此项技术在矿山地质测绘工作中应用所需要注意的具体问题。最后,本文通过实际案例,深入探索GPS测绘技术在矿山地质测绘中的实际应用要点,为今后我国的矿山勘探测绘工作开展提供更加实际的... 详细信息

本文中对GPS测绘技术的具体内容进行论述,并说明此项技术在矿山地质测绘工作中应用所需要注意的具体问题。最后,本文通过实际案例,深入探索GPS测绘技术在矿山地质测绘中的实际应用要点,为今后我国的矿山勘探测绘工作开展提供更加实际的参考,推动我国采矿业的进一步发展。

关键词： GPS 测绘技术矿山地质测绘

脑梗死后癫痫发作诊断中视频脑电图检查的作用

同方期刊数据库博看期刊评论

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中国医疗器械信息 2024年第13期30卷 110-112页

作者：周旺侨陈晓云王美慧厦门市第三医院福建厦门361000

目的:分析脑梗死后癫痫发作诊断中视频脑电图检查的作用。方法:将2020年7月~2023年5月本院收治的80例患者作为研究对象,依据抽签法将其分为对照组与观察组,各40例,对照组实施常规脑电图检查,观察组实施视频脑电图检查,对比两组检测结果... 详细信息

目的:分析脑梗死后癫痫发作诊断中视频脑电图检查的作用。方法:将2020年7月~2023年5月本院收治的80例患者作为研究对象,依据抽签法将其分为对照组与观察组,各40例,对照组实施常规脑电图检查,观察组实施视频脑电图检查,对比两组检测结果。结果:两组暴发性癫痫样放电、局限性癫痫样放电、周期性一侧癫痫样放电、局限性慢波活动、脑电波左右不对称等指标对比,差异有统计学意义(P<0.05);观察组同步发作、深部白质区癫痫样波检出、脑叶皮质区癫痫样波检出率高于对照组,差异有统计学意义(P<0.05)。结论:视频脑电图对患者的应用可以提升暴发性癫痫样放电、局限性癫痫样放电、周期性一侧癫痫样放电、局限性慢波活动、脑电波左右不对称、背景节律慢、背景无节律的检出率,也可以促进同步发作、深部白质区有癫痫样波、脑叶皮质区癫痫样波的检出,为之后获得有效治疗提供必要支持。

关键词：脑梗死后癫痫发作视频脑电图检查诊断价值

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不同分子结构聚酰胺热分解机理研究

分析测试学报 2024年第9期43卷 1338-1347页

作者：王佳敏史迎杰白云邹文奇王美慧高峡郝新敏北京市科学技术研究院分析测试研究所(北京市理化分析测试中心) 有机材料检测技术与质量评价北京市重点实验室北京市食品安全分析测试工程技术研究中心北京100089 军事科学院系统工程研究院北京100010

采用热分析-红外-质谱联用仪(STA-FTIR-MS)和热裂解/气相色谱-质谱联用仪(Py/GC-MS)对聚酰胺56(PA56)与聚酰胺6(PA6)、聚酰胺66(PA66)的热分解行为进行了比较研究。旨在阐明PA56与PA6、PA66在热分解过程中表现出的差异性及热裂解机理特... 详细信息

采用热分析-红外-质谱联用仪(STA-FTIR-MS)和热裂解/气相色谱-质谱联用仪(Py/GC-MS)对聚酰胺56(PA56)与聚酰胺6(PA6)、聚酰胺66(PA66)的热分解行为进行了比较研究。旨在阐明PA56与PA6、PA66在热分解过程中表现出的差异性及热裂解机理特点。通过阿伦尼乌斯(Arrhenius)方程计算反应活化能(Ea),并进一步通过热裂解实验对PA6、PA66、PA56的热降解产物进行分析。结果表明:PA6、PA66、PA56在氩气中的热降解过程均为一步反应,热降解活化能数值PA6>PA66>PA56,均大于185 kJ/mol,表明三者都具有良好的热稳定性,且PA56相比PA6、PA66热稳定性更好。三者的断裂方式相似,均以酰胺键的α位断裂为主。

关键词：聚酰胺热降解动力学裂解机理

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Contribution of intraseasonal oscillation to long-duration summer precipitation events over southern China

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Atmospheric and Oceanic Science Letters 2017年第1期10卷 82-88页

作者： LIU Ge WU Ren-Guang wang hui-mei State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science & Technology Center for Monsoon System Research Institute of Atmospheric PhysicsChinese Academy of Sciences

Precipitation events spanning multiple days may have consequences different from those limited to a single *** the present paper,the authors analyze circulation anomalies and precursory signals associated with long-duration（over 14 days） summer precipitation events over southern *** results show that the over-14-day precipitation events are induced by an anomalous lowertropospheric（850-hPa） cyclone over the South China Sea（SCS） and southern *** anomalous westerly winds to the south of the anomalous cyclone can be traced to north of New Guinea 30 days *** the north of anomalous westerly winds,anomalous easterly winds appear *** anomalous westerly and easterly winds form a cyclonic anomaly,moving northward and slightly westward during the following days and eventually controlling the SCS and southern *** northward movement of anomalous westerly and easterly winds can also be found in the 30-60-day filtered wind *** implies that the northward propagating 30-60-day intraseasonal oscillation from the equatorial western Pacific has an important contribution to over-14-day precipitation events over southern China.

关键词： Precipitation event long duration southern China intraseasonal oscillation

A new lignan derivative from the root of Ilex pubescens

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Chinese Chemical Letters 2008年第5期19卷 550-552页

作者： Yu Bo Zhou Jin hui wang Xiang mei Li Xian Li School of Traditional Chinese Materia Medica Shenyang Pharmaceutical University Shenyang 110016 China

One new compound, ilexlignan A （1）, was isolated from the root of llex pubescens. Its structure was elucidated by the combination of one- and two-dimensional NMR analysis, mass spectrometry, CD spectrum measurement ... 详细信息

关键词： llex pubescens llexlignan A Lignan

Identification of a Gravitropism-Deficient Mutant in Rice

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Rice science 2017年第2期24卷 109-118页

作者： HE Yan SHI Yong-feng ZHANG Xiao-bo wang hui-mei XU Xia WU Jian-li State Key Laboratory of Rice Biology/Chinese National Center for Rice Improvement China National Rice Research InstituteHangzhou 310006China

A gravitropism-deficient mutant M96 was isolated from a mutant bank, generated by ethyl methane sulfonate(EMS) mutagenesis of indica rice accession ZJ100. The mutant was characterized as prostrate growth at the beginning of germination, and the prostrate growth phenotype ran through the whole life duration. Tiller angle and tiller number of M96 increased significantly in comparison with the wild type. Tissue section observation analysis indicated that asymmetric stem growth around the second node occurred in M96. Genetic analysis and gene mapping showed that M96 was controlled by a single recessive nuclear gene, tentatively termed as gravitropism-deficient M96(gd M96), which was mapped to a region of 506 kb flanked by markers RM5960 and In Del8 on the long arm of chromosome 11. Sequencing analysis of the open reading frames in this region revealed a nucleotide substitution from G to T in the third exon of LOC_Os11g29840. Additionally, real-time fluorescence quantitative PCR analysis showed that the expression level of LOC_Os11g29840 in the stems was much higher than in the roots and leaves in M96. Furthermore, the expression level was more than four times in M96 stem than in the wild type stem. Our results suggested that the mutant gene was likely a new allele to the reported gene LAZY1. Isolation of this new allele would facilitate the further characterization of LAZY1.

关键词： plant architecture gravitropism LAZY1 gene mapping mutant

Research on intelligent search-and-secure technology in accelerator hazardous areas based on machine vision

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Nuclear Science and Techniques 2024年第4期35卷 96-107页

作者： Ying-Lin Ma Yao wang Hong-mei Shi hui-Jie Zhang School of Traffic and Transportation Beijing Jiaotong UniversityBeijing 100044China School of Mechanical Electronic and Control EngineeringBeijing Jiaotong UniversityBeijing 100044China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Prompt radiation emitted during accelerator operation poses a significant health risk,necessitating a thorough search and securing of hazardous areas prior to ***,manual sweep methods are ***,the limitations of manual sweeps have become increasingly evident with the implementation of large-scale *** leveraging advancements in machine vision technology,the automatic identification of stranded personnel in controlled areas through camera imagery presents a viable solution for efficient search and *** the criticality of personal safety for stranded individuals,search and security processes must be sufficiently *** ensure comprehensive coverage,180°camera groups were strategically positioned on both sides of the accelerator tunnel to eliminate blind spots within the monitoring *** YOLOV8 network model was modified to enable the detection of small targets,such as hands and feet,as well as larger targets formed by individuals near the ***,the system incorporates a pedestrian recognition model that detects human body parts,and an information fusion strategy is used to integrate the detected head,hands,and feet with the identified pedestrians as a cohesive *** strategy enhanced the capability of the model to identify pedestrians obstructed by equipment,resulting in a notable improvement in the recall ***,recall rates of 0.915 and 0.82were obtained for Datasets 1 and 2,*** there was a slight decrease in accuracy,it aligned with the intended purpose of the search-and-secure software *** tests conducted within an accelerator tunnel demonstrated the effectiveness of this approach in achieving reliable recognition outcomes.

关键词： Search and secure Machine vision Camera Human body parts recognition Particle accelerator Hazardous area