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Journal of Earth Science 2024年第1期35卷 112-130页

作者： Jile Chen Peimin Zhu yuefeng yuan Guifan Chen School of Geophysics and Geomatics China University of GeosciencesWuhan 430074China Geothermal Engineering Research Center Three Gorges Geotechnical Consultants Co.Ltd.Wuhan 430074China

Various models exist to explain the formation of the Tibetan Plateau,including“tectonic escape”,“pure shear thickening”,“convective removal of the lithospheric mantle”,and“lower crustal flow”model.The first two models are primarily constructed on pure mechanical models but are unable to reasonably explain the tension and shear phenomena inside the plateau.The latter two are rheological dynamic models based on deep geophysical observations.However,the spatial range of the lower crustal flow and its role in the plateau formation/uplift remain controversial.Five multi-terrane viscoplastic thermomechanical models were constructed to simulate the uplift and lithospheric structure change of the Tibetan Plateau during the post-collision stage(since 35 Ma)under the convergence of the Indian Plate.Results show that the plateau's formation begins with crustal thickening,blocked by strong terranes at the northern plateau,and expanded laterally to the east.The lithosphere thickens gradually and experiences delamination at its base,elevating temperature within the crust and forming partial melting layers in the central plateau.As convergence persists on the southern side,the northern plateau's lithosphere bends downward and undergoes delamination,further heating the crust and promoting the northward and eastward flow of partial melting layers,leading to secondary uplift around the plateau.

关键词： 3-D thermomechanical modeling Tibetan Plateau plateau uplift crustal flow

Genetic Analysis of Structural Styles in the Makran Accretionary Wedge–Insight from Physical Simulations

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Journal of Ocean University of China 2024年第1期23卷 157-172页

作者： SHAO Longfei YU Fusheng GONG Jianming LIAO Jing YU Zhifeng TANG Liang CHEN Jiangong WANG yuefeng NENG yuan School of Earth Sciences China University of PetroleumBeijing 102249China State Key Laboratory of Petroleum Resources and Processing China University of PetroleumBeijing 102249China Qingdao Institute of Marine Geology China Geological SurveyQingdao 266071China China University of Petroleum–Beijing at Karamay Karamay 834000China

The Makran accretionary wedge has the smallest subduction angle among any accretionary prism in the world. The factors controlling the spacing and morphological development of its deep thrust faults, as well as the formation mechanism of shallow normal faults, remain unclear. Meanwhile, the factors affecting the continuity of plane faults must be comprehensively discussed. Clarifying the development characteristics and deformation mechanisms of the Makran accretionary wedge is crucial to effectively guide the exploration of gas hydrate deposits in the area. This study aims to interpret seismic data to identify typical structures in the Makran accretionary wedge, including deep imbricate thrust faults, shallow and small normal faults, wedge-shaped piggyback basins, mud diapirs with fuzzy and disorderly characteristics of reflection, décollements with a northward tilt of 1° – 2°, and large seamounts. Physical simulation-based experiments are performed to comprehensively analyze the results of the plane, section, and slices of the wedge. Results reveal that the distances between and shapes of thrust faults in the deep parts of the Makran accretionary wedge are controlled by the bottom décollement. The uplift of the thrust fault-related folds and the upwelling of the mud diapirs primarily contribute to the formation of small normal faults in the shallow part of the area. The mud diapirs originate from plastic material at the bottom, while those that have developed in the area near the trench are larger. Seamounts and mud diapirs break the continuity of fault plane distribution.

关键词： Makran accretionary wedge structural styles faults distribution physical simulation

Enhancing alkyne semi-hydrogenation through engineering metal-support interactions of Pd on oxides

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Nano Research 2024年第5期17卷 3707-3713页

作者： yuefeng Wu Xiaotong Lu Pengfei Cui Wenyu Jia Jun Zhou yuan Wang Hussain Zahid Yuxin Wu Muhammad Umer Rafique Xiong Yin Baoshan Li Leyu Wang Guolei Xiang State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBeijing 100029China CAS Key Laboratory of Science and Technology on Applied Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China College of Chemical Engineering Beijing University of Chemical TechnologyBeijing 100029China

Supported Pd catalysts show superior activities for olefin productions from alkynes through semi-hydrogenation reactions,but over-hydrogenation into alkanes highly decreases olefin selectivity.Using phenylacetylene semi-hydrogenation as a model reaction,here we explore the optimization approaches toward better Pd catalysts for alkyne semi-hydrogenation through investigating support effect and metal-support interactions.The results show that the states of Pd with supports can be tuned by varying oxide reducibility,loading ratios,and post-treatments.In our system,0.06 wt.%Pd on rutile-TiO_(2) nanorods shows the highest activity owing to the synergistic effects of single-atoms and clusters.Support reducibility can change the filling degrees of Pd 4d orbitals through varying interfacial bonding strengths,which further affect catalytic activity and selectivity.

关键词： alkyne semi-hydrogenation support effect metal-support interaction Pd catalyst single-atom catalyst

Recent progress on high-temperature superconducting filters

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Superconductivity 2022年第2期2卷 28-38页

作者： Chi Zhang Wei Xie Chunguang Li Jinhao Dai yuefeng yuan Runbo Jiang Xu Wang Jia Wang Yun Wu Liang Sun Yusheng He Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100190China Southwest China Research Institute of Electronic Equipment Chengdu 610036China Henan University of Science and Technology Luoyang 471000China Songshan Lake Materials Laboratory Dongguan 523808China

Since the discovery of high temperature superconducting(HTS)materials in 1987,the performance of microwave filters such as insertion loss,selectivity,and out-band rejection has been significantly improved by utilizing HTS films.Nowadays,HTS filters have been widely used in wireless communications,space exploration,satellite communications,and several other fields.HTS filters with a special performance,such as wideband,dual-band or multiband,frequency tunable,and high power-handling capability have been designed and fabricated in recent years to meet the increasing requirements of practical applications and to further extend the application areas.This paper reviews the various types of above-mentioned HTS filters as well as the developments of novel design methodologies.

关键词： High-temperature superconductors Microwave filters Wideband Dual-band Frequency-tunable High power handling

脊柱胸腰段应力分布与骨折相关性的三维有限元分析

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中国脊柱脊髓杂志 2024年第4期34卷 408-417页

作者：袁飞任杰唐悦峰申小刚郭涛贵州医科大学临床医学院贵阳市550004 贵州省人民医院骨科贵阳市550499

目的:观察脊柱胸腰段骨折与椎体骨性结构及韧带间应力分布的相关性,探索脊柱胸腰段椎体骨折的力学机制。方法:招募8名健康男性青年志愿者,行脊柱全长X线片和CT检查排除脊柱畸形、肿瘤及骨病,对脊柱各椎体及股骨行骨密度测定排除骨质疏... 详细信息

目的:观察脊柱胸腰段骨折与椎体骨性结构及韧带间应力分布的相关性,探索脊柱胸腰段椎体骨折的力学机制。方法:招募8名健康男性青年志愿者,行脊柱全长X线片和CT检查排除脊柱畸形、肿瘤及骨病,对脊柱各椎体及股骨行骨密度测定排除骨质疏松。均行自T11椎体上终板至L2椎体下缘CT薄层扫描,将8名志愿者CT图像参数导入ABAQUS 2016软件中进行标准化,并进行有限元网格化构建。应用MIMICS 17.0、GEOMAGICS 15.0和PRO/ENGINEER 5.0软件处理,建立脊柱胸腰段有限元模型,测量模型相关参数,并验证模型有效性。在T11椎体上终板上加载竖直轴向载荷500N、附加扭矩10N·m模拟垂直压缩、前屈、后伸、左右侧屈、左右旋转7种运动状态,使用ABAQUS软件对有限元模型7种运动状态下的应力分布特点及变化规律进行分析,观察应力分布与脊柱胸腰段骨折的相关性。结果:建立的三维有限元模型共有309583个节点和428760个单元,包括4个椎体、3个椎间盘、前纵韧带、后纵韧带、横突间韧带、棘间韧带等结构。7种运动状态下的数据与文献报道的数据无明显偏差,模型有效。T11~L2椎体椎弓根截面积分别为135mm^(2)、154mm^(2)、105mm^(2)、139.2mm^(2)。应力云图结果显示各运动状态下高应力区存在于椎体的松质骨、椎弓根及其周围骨皮质。在垂直压缩状况下,T12椎体所受应力最大(617.4MPa),前屈状态下T11所受应力最大(200.7MPa),后伸、左右侧屈和左右旋转状态下L1椎体所受应力最大(314.2MPa、574.4MPa、626.2MPa、641.3MPa、527.1MPa),且前屈体位时椎体所能承受的应力最小,左旋转时所能承受的应力最大。垂直压缩状况下T12椎体发生骨折,前屈状态下T11发生骨折伴韧带损伤,后伸、左右侧屈和左右旋转状态下L1椎体发生骨折伴韧带损伤。骨折发生时,前纵韧带在后伸、左右侧屈状态下存在高应力区,后纵韧带在前屈状态下存在高应力区,横突间韧带和棘间韧带在前屈、左右侧屈、左右旋转状态下存在高应力区。结论:在构建包括重要韧带、椎间盘等软组织结构的脊柱胸腰段三维模型中,椎体松质骨、椎弓根及其周围骨皮质、韧带均存在高应力区,不同状态下所受应力最大椎体不同,发生骨折的椎体和韧带损伤也不同;L1椎弓根截面积最小,最易发生骨折。

关键词：椎体骨折胸腰段脊柱三维有限元模型应力分析

地下水位变化对砂土地层地铁隧道沉降影响试验研究

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中国铁道科学 2024年第1期45卷 122-130页

作者：黄大维李彬鑫石钰锋胡光静袁岳峰詹涛华东交通大学轨道交通基础设施性能监测与保障国家重点实验室江西南昌330013 华东交通大学江西省防灾减灾及应急管理重点实验室江西南昌330013 中铁广州工程局集团有限公司广东广州511457 南昌轨道交通集团有限公司地铁项目管理分公司江西南昌330038

为考察地铁运营后列车载荷和地下水对隧道造成的影响,对某砂性土地层城市中某一地铁盾构隧道区段运营6年间的沉降变形进行实测观察;根据实测所得沉降规律,设计并开展缩尺模型试验,研究车致振动条件下因地下水位变化产生的隧道沉降规律... 详细信息

为考察地铁运营后列车载荷和地下水对隧道造成的影响,对某砂性土地层城市中某一地铁盾构隧道区段运营6年间的沉降变形进行实测观察;根据实测所得沉降规律,设计并开展缩尺模型试验,研究车致振动条件下因地下水位变化产生的隧道沉降规律。结果表明:随着时间推移,隧道各测点所得数据呈现一定的周期性上升与下降变化趋势,前2年隧道总体上浮,之后略有沉降,第3年后虽有波动但基本未发生进一步沉降,第6年后隧道最大沉降不超过3 mm;砂性土地层中,地下水位变化会造成重塑土层内部应力变化,且振动荷载会导致土体颗粒结构重新调整至密实,易导致隧道发生沉降,因此不能忽视地铁周围施工降水给隧道带来的不利影响;土体振密及因地下水产生的浮力共同作用,导致隧道的上浮及沉降。相比于软土地层,砂性土地层中盾构隧道的沉降速率明显更低且沉降基本稳定时间更短,2种地层下的沉降规律、影响因素完全不同,各地层下的沉降分析理论亦无法相互适用。

关键词：盾构隧道隧道沉降砂土地层地下水位车致振动

基于卫星观测的青岛O_(3)污染特征及生成敏感性

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环境科学与技术 2024年第3期47卷 93-100页

作者：薛莲方渊刘岳峰孟赫郝勇代玮韩矗山东省青岛生态环境监测中心山东青岛266003 青岛市环境保护科学研究院山东青岛266071 青岛镭测创芯科技有限公司山东青岛266100

文章基于哨兵-5P卫星和激光雷达等观测结果,研究了2022年5月17-22日青岛市O_(3)污染过程的变化特征、对流层柱浓度分布及生成敏感性。结果表明,此次过程受区域增温、太阳辐射增强、逆温等不利污染扩散条件影响,还受区域污染物的传输和... 详细信息

文章基于哨兵-5P卫星和激光雷达等观测结果,研究了2022年5月17-22日青岛市O_(3)污染过程的变化特征、对流层柱浓度分布及生成敏感性。结果表明,此次过程受区域增温、太阳辐射增强、逆温等不利污染扩散条件影响,还受区域污染物的传输和高空沉降影响。对流层O_(3)及前体物HCHO、NO_(2)柱浓度具有明显的空间分布差异。O_(3)生成敏感性分析表明,青岛市区和郊区的大部分地区处在VOCs和NOx协同控制区,需要优化两者减排比例,协同控制;远郊区一般处在NOx控制区;石化区主要处在VOCs控制区。

关键词：卫星观测 O_(3)污染过程柱浓度生成敏感性

基于改进SMO与变参数LTD的PMSM无传感器控制

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组合机床与自动化加工技术 2024年第4期 105-109页

作者：代成刚杨其华袁月峰李锐鹏中国计量大学机电工程学院杭州310018

为解决基于滑模观测器的PMSM无感控制系统抖振大、响应速度慢等问题,在转速环PI控制器前引入变参数线性跟踪微分器,实现由I/F起动向转速-电流双闭环控制模式的平稳过渡。采用sigmoid函数替换sign函数消除由sign函数在滑模面切换给等效... 详细信息

为解决基于滑模观测器的PMSM无感控制系统抖振大、响应速度慢等问题,在转速环PI控制器前引入变参数线性跟踪微分器,实现由I/F起动向转速-电流双闭环控制模式的平稳过渡。采用sigmoid函数替换sign函数消除由sign函数在滑模面切换给等效反电动势带来的高次谐波;根据反电动势与电机转速关系以自适应滑模增益提高系统响应速度,并利用李雅普诺夫稳定性判据分析改进后算法稳定性。在仿真平台以及PMSM控制系统上进行控制算法验证,表明了所提出的改进PMSM无传感器控制策略对抑制系统抖振与提高系统的响应速度具有良好的效果。

关键词：滑模观测器变参数线性跟踪微分器 I/F起动 sigmoid函数自适应滑模增益

基于总量统计矩分析法与分子连接性指数探讨枳实、枳壳“同源异效”的物质基础

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中国实验方剂学杂志 2024年第3期30卷 161-168页

作者：袁筱吴月峰李世雄刘有志于芷芩贺福元周晋湖南中医药大学药学院中药成药性与制剂制备湖南省重点实验室中医药超分子机理与数理特征化实验室长沙410208

目的:基于总量统计矩分析法与分子连接性指数(MCI)探讨枳实与枳壳“同源异效”的物质基础。方法:查阅国内外相关文献和中药系统药理学数据库与分析平台(TCMSP),建立枳实、枳壳的化学成分数据库,建立其超高效液相色谱法(UPLC)指纹图谱,... 详细信息

目的:基于总量统计矩分析法与分子连接性指数(MCI)探讨枳实与枳壳“同源异效”的物质基础。方法:查阅国内外相关文献和中药系统药理学数据库与分析平台(TCMSP),建立枳实、枳壳的化学成分数据库,建立其超高效液相色谱法(UPLC)指纹图谱,计算指纹图谱总量统计矩及其相似度参数;根据MCI将枳实、枳壳所有成分划分为不同的成分群;计算枳实、枳壳共有成分群0~8阶(^(0)χ~^(8)χ)MCI平均值。结果:枳实与枳壳的总量零阶矩(AUCT)分别为(10.57±2.45)×10^(6)、(5.09±0.89)×10^(6)μV·s,总量一阶矩(MCRT_(T))分别为(11.57±1.58)、(12.10±1.29)min,总量二阶矩(VCRTT)分别为(24.49±2.30)、(26.49±2.54)min^(2),表明枳实与枳壳定性、定量参数都存在明显差异;筛选出新橙皮苷、橙皮苷、芸香柚皮苷等相似度高的成分作为枳实、枳壳共有潜在药效成分;筛选出枳实中非共有成分alysifolinone、欧前胡素等,枳壳中非共有成分新北美圣草苷、异樱花苷等相似度高的作为枳实、枳壳各自潜在“异效”成分;将枳实与枳壳成分群划分为六类,枳实、枳壳成分群与总成分之间的相似度分别在0.872~0.979、0.918~0.997,枳实与枳壳的生物碱类成分^(0)χ~^(8)χMCI平均值分别为3.65、3.14,黄酮类成分^(0)χ~^(8)χMCI平均值均为8.47,挥发油类成分^(0)χ~^(8)χMCI平均值分别为2.71、3.48,表明枳实与枳壳化学成分(群)MCI存在一定差异。结论:枳实与枳壳化学成分(群)不仅是含量与种类的差异,其结构特点及构效关系也存在差异,可为深入阐释枳实、枳壳“同源异效”的科学内涵提供依据。

关键词：枳实枳壳同源异效分子连接性指数(MCI) 总量统计矩指纹图谱超高效液相色谱法(UPLC) 物质基础

Impacts of different designed microstructures on creep performance of a Ni-based wrought superalloy

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Progress in Natural Science:Materials International 2023年第5期33卷 625-633页

作者： Hao Liu Xinbao Zhao yuan Cheng Jiachen Xu Shuhao Cheng Quanzhao Yue Yong yuan yuefeng Gu Ze Zhang Institute of Superalloys Science and Technology School of Materials Science and Engineering Zhejiang University Polytechnic Institute Zhejiang University State Key Laboratory of Silicon and Advanced Semiconductor Materials Zhejiang University Xi'an Thermal Power Research Institute Co.Ltd.

The creep behavior of a novel Ni-based wrought superalloy with varying aging states, classified as large underaged(UA), little UA, and little over-aged(OA) states, was investigated at a temperature higher than the intragrain/grain-boundary iso-strength temperature(750°C/250 MPa). In the samples before creep test, there are spherical γ’precipitates homogeneously dispersed within the γ matrix and carbides precipitated at grain boundaries(GBs). After creep tests, precipitate-free zones(PFZs) appear on grain boundaries, with a large blocklike γ’phase present between carbides and PFZs, potentially serving as initiation sites for cracks. Little UA state samples exhibit the strongest creep resistance and intergranular fracture. The dominant creep deformation mechanism in the intra-grain is a combination of Orowan process involving slip and climb of matrix dislocations and shearing of γ’precipitates. The results indicate that the optimizing the grain boundary microstructure may be more important than the change of intragranular microstructure when the creep temperature exceeds the isostrength temperature.

关键词： Creep performance Intragranular microstructure Ni-based wrought superalloy