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西南印度洋中脊东段MORB微量元素地球化学及其对地幔源区组成的指示

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海洋地质与第四纪地质 2024年第4期44卷 99-107,I0001-I0003页

作者：董振梁锦曹志敏贺惠忠陈亮陆茸中国海洋大学海洋地球科学学院青岛266100 自然资源部南海调查中心海洋环境探测技术与应用重点实验室广州510275 自然资源部第二海洋研究所海底科学重点实验室杭州310012

西南印度洋中脊东段(E-SWIR)处于61°~70°E区域,具有相对匮乏的熔体供给。该区产出的大多数洋中脊玄武岩(MORB)具有富集不相容元素以及大离子亲石元素等特征,属典型E-MORB。基于玄武岩样品的微量元素地球化学资料,通过La/Sm、Zr/Nb和Lu... 详细信息

西南印度洋中脊东段(E-SWIR)处于61°~70°E区域,具有相对匮乏的熔体供给。该区产出的大多数洋中脊玄武岩(MORB)具有富集不相容元素以及大离子亲石元素等特征,属典型E-MORB。基于玄武岩样品的微量元素地球化学资料,通过La/Sm、Zr/Nb和Lu/Tb等分析表明E-SWIR地幔具有明显的不均一性,这种不均一性可能与地幔中辉石岩含量的沿轴变化有关。利用稀土元素Ce、Sm、Lu和Yb含量结合部分熔融计算模拟结果,进一步阐明地幔源区中石榴石的作用与影响,并且认为其可能是以含金红石榴辉岩的形式赋存于地幔之中。对E-SWIR地幔源区榴辉岩性质和赋存形式的识别是探讨EMORB成因、地幔不均一性与洋中脊构造演化等科学问题的关键。

关键词：元素地球化学地幔源区组成洋中脊玄武岩西南印度洋中脊东段

母婴分离初产妇出院准备护理实践现况的田野研究

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中国实用护理杂志 2024年第4期40卷 250-256页

作者：万悦丁丽静姚晓王佳洁吴娜黄蓉同济大学医学院护理学院上海200092 同济大学附属妇产科医院产科上海201204

目的了解母婴分离初产妇出院准备护理实践现况,为构建临床护理方案提供参考和依据。方法2023年2—6月,选取同济大学附属妇产科医院产科作为田野地,开展针对母婴分离初产妇出院准备护理实践现况的田野研究。通过参与式观察及非正式访谈收... 详细信息

目的了解母婴分离初产妇出院准备护理实践现况,为构建临床护理方案提供参考和依据。方法2023年2—6月,选取同济大学附属妇产科医院产科作为田野地,开展针对母婴分离初产妇出院准备护理实践现况的田野研究。通过参与式观察及非正式访谈收集12名护士的资料并采用质性研究中三级编码的方法进行资料分析。结果12名护士均为女性,年龄24~46(33.33±1.83)岁。母婴分离初产妇出院准备护理包括提供新生儿健康信息、母乳喂养、产后康复、心理护理及社会支持共4类内容主题;护士在提供新生儿健康知识、评估母婴分离初产妇心理及社会支持、出院教育质量等方面存在提升空间。结论母婴分离初产妇出院准备护理缺乏结构合理的流程及制度,亟需通过制订科学规范的出院准备护理流程,对护士进行规范化培训,提高护士心理社会评估能力,同质化健康教育,提升人文关怀等措施,提高母婴分离初产妇出院准备护理质量,从而促进初产妇康复,并适应母亲角色。

关键词：病人出院母婴护理初产妇田野研究

基于等效刚度阻尼系统的中低速磁浮列车与大跨度桥梁耦合振动响应分析

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计算力学学报 2024年第4期41卷 634-640,650页

作者：罗浩徐楚懿甘贤备刘谋刚郭向荣湖南科技大学土木工程学院湘潭411201 中南大学土木工程学院长沙410075

针对中低速磁浮列车与大跨度连续梁桥的耦合动力响应问题,本文基于等效刚度阻尼系统建立多编组磁浮列车模型;基于国内在建磁浮专线连续梁桥(35m+55m+35m),采用ANSYS中实体单元建立全桥模型.并将两个独立系统在SIMPACK进行车桥耦合,设定... 详细信息

针对中低速磁浮列车与大跨度连续梁桥的耦合动力响应问题,本文基于等效刚度阻尼系统建立多编组磁浮列车模型;基于国内在建磁浮专线连续梁桥(35m+55m+35m),采用ANSYS中实体单元建立全桥模型.并将两个独立系统在SIMPACK进行车桥耦合,设定车重参数分别为空载、定员和超载,且列车按单线和双线工况运行,计算耦合系统的动力响应.结果表明,本文建立的列车模型受到轨道激励时,磁浮间隙在额定范围内浮动,即等效刚度阻尼系统有良好的控制效果;车辆磁浮间隙的变化量、车体竖向加速度与车重成反比,而磁浮力与车重成正比;在计算工况下,桥梁主跨及边跨的竖向位移均满足设计要求的限值,双线列车超载运行桥梁跨中最大位移仅为4.503mm.说明连续梁桥具有较大的刚度,能满足磁浮车辆安全运行的要求;对比列车单双线运行,主跨跨中的竖向位移最大值后者达到前者两倍,而边跨位移的最大值后者仅比前者增大70%,表明双线列车对开运行对桥梁的动力响应存在增大效应.相关研究成果对磁浮线路建设有一定参考意义.

关键词：磁浮列车连续梁桥车桥耦合位移限值

Installation error calibration for MEMS angular measurement system in hypersonic wind tunnel

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Chinese Journal of Aeronautics 2023年第5期36卷 175-186页

作者： Xiong WANG Xueling ZHAO Bin ZHOU Qi WEI rong ZHANG Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang 621000China Department of Precision Instrument Tsinghua UniversityBeijing 100084China

The accuracy of model attitude measurement has an important impact on wind tunnel test results. Microelectromechanical System Inertial Measurement Unit(MEMS IMU) provides a feasible way to measure model attitudes with high accuracy. However, the installation error between MEMS IMU coordinate system and the body coordinate system of test models can make the accuracy of the model attitude measurement decrease. In wind tunnel tests, the installation error depends on the relationship between the IMU and the model mechanism before tests. Therefore, infield calibration in wind tunnel tests is necessary to reduce installation errors. To improve attitude measurement accuracy, the least squares quaternion calibration method based on MEMS IMU and six-position calibration procedure are proposed. High-precision three-axis turntable tests are performed. The pitch accuracy after calibration is higher than that before calibration in the angle of attack sweeping tests. The Root-Mean-Square Errors(RMSE) in the roll and yaw are within0.01°, which are smaller than those before calibration. In the roll sweeping tests, RMSE of three attitude angles decrease significantly. In hypersonic wind tunnel tests, the pitch errors before and after calibration are within 0.05° and 0.02° in the angle of attack sweeping tests without wind. In five angle of attack sweeping tests with wind, the deviation between the mean of the pitch and the pitch after the elastic angle correction is within 0.03° and the standard deviation of five tests is within 0.01°. The proposed method is confirmed to enhance the accuracy of attitude measurement effectively, which is convenient for engineering applications.

关键词： Calibration Installation error Least squares MEMS Model attitude measurement Quaternion Wind tunnel test

Dynamo Effect Due to Plasma Motion

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Chinese Physics Letters 1999年第8期16卷 616-618页

作者： YANG Zhi-liang JING Hai-rong Department of Astronomy Beijing Normal UniversityBeijing 100875

On the basic Maxwell equations in moving media,the magnetic induction equation in the moving plasma is derived.A more efficient dynamo transforming kinetic energy of the moving plasma to magnetic energy is obtained with this *** model of dynamo possesses to oscillatory *** oscillation of magnetic field can explain the variation of the solar magnetic field.

关键词： equation. field. moving

Model test of the mechanism underpinning water-and-mud inrush disasters during tunnel excavation in sandstone and slate interbedded Presinian strata

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2022年第11期23卷 882-899页

作者： Peng XU Peng PENG rong-hua WEI Zhi-qiang ZHANG School of Civil Engineering Southwest Jiaotong UniversityChengdu 610031China Key Laboratory of Transportation Tunnel Engineering Ministry of EducationSouthwest Jiaotong UniversityChengdu 610031China

Water-and-mud inrush disasters have become a major challenge in underground engineering for the construction of tunnels in sandstone and slate interbedded Presinian *** prediction and prevention rely in part on realistic modeling and observation of the disaster process,as well as the identification and examination of the underlying *** on the geological conditions and the historical records of the Xinping Tunnel on the China–Laos Railway,an engineering geological model of the water-and-mud inrush was established.A physical model test that accurately reproduced water-and-mud inrush during tunnel excavation in sandstone and slate interbedded strata was also carried ***,testing was conducted that examined the stress and strain,seepage pressure,and high-leakage flow of the surrounding *** results indicated that the water-and-mud inrush proceeded through three stages:seepage stage,high-leakage flow stage,and attenuation *** essence,the disaster was a catastrophic process,during which the water-resistant stratum was reduced to a critical safety thickness,a water-inrush channel formed,and the water-resistant stratum gradually failed under the influence of excavation unloading and in situ stress–seepage *** such as the stress and strain,seepage pressure,and flow of the surrounding rock had evident stage-related features during water-and-mud inrush,and their variation indicated the formation,development,and evolution of the *** the tunnel face advanced,the trend of the stress–strain curve of the surrounding rock shifted from sluggish to rapid in its speed of *** characteristics of strain energy density revealed the erosion and weakening effect of groundwater on the surrounding *** seepage pressure and the thickness of the water-resistant stratum had a positive linear relationship,and the flow and thickness a negative linear *** was a pivotal point at which the seepage pressure change

关键词： Water-and-mud inrush Sandstone and slate interbedded Presinian strata Model test Evolution law Thickness of water-resistant stratum Inducing mechanism

Design and Dynamic Analysis of the Recirculating Planetary Roller Screw Mechanism

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Chinese Journal of Mechanical Engineering 2022年第4期35卷 240-255页

作者： Guan Qiao rong Liao Shijie Guo Zhenghong Shi Shangjun Ma Inner Mongolia Key Laboratory of Advanced Manufacturing Technology Inner Mongolia University of TechnologyHohhot 010051China University of Cincinnati CincinnatiOH 45221USA Shaanxi Engineering Laboratory for Transmissions and Controls Northwestern Polytechnical UniversityXi’an 710072China

The recirculating planetary roller screw mechanism(RPRSM)is a transmission mechanism that engages the screw and nut threaded by multiple grooved *** this paper,frstly,the design method of RPRSM nut threadless area is proposed,and the equations related to the structural parameters of nut threadless area are *** this basis,the cross-section design method of roller,screw and nut is constructed according to the actual situation of engagements between the screw/nut and the *** adjusting the gap between the two beveled edges and that between the arc and the beveled edge,the accuracy of the thread engagements between the screw/nut and the roller can be ***,to ensure the engagements of the screw/nut and the roller,the distance equation from the center surface of the diferent rollers to the end surface of cam ring is ***,combined with the working principle and structural composition of RPRSM,the component model is established according to its relevant structural parameters,and the virtual assembly is ***,the 3D model is imported into the ADAMS simulation software for multi-rigid body *** dynamic characteristic is analyzed,and the simulated values are compared with the theoretical *** results show that the contact forces between the screw/nut and the roller are sinusoidal,mainly due to the existence of a small gap between the roller and the *** maximum collision forces between the roller and cam ring are independent from load ***,the collision force between the roller and the carrier increases as the load *** RPRSM is in the transmission process,the roller angular speed in nut threadless area begins to appear abruptly,and the position of the maximum change is at the contact between the roller and the convex platform of cam *** design of the nut threadless area and the proposed virtual assembly method can provide a theoretical guidance for RPRSM research,as well as

关键词： Recirculating planetary roller screw mechanism Nut threadless area Virtual assembly method Motion relationship Dynamic analysis

Monolayer MoS_(2) epitaxy

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Nano Research 2021年第6期14卷 1598-1608页

作者： Zheng Wei Qinqin Wang Lu Li rong Yang Guangyu Zhang Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of SciencesBeijing100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing100190China Songshan Lake Materials Laboratory Dongguan523808China

As an emerging two-dimensional(2D)semiconductor material,monolayer MoS2 has recently attracted considerable *** promising applications of this material have been proposed for electronics,optoelectronics,sensing,catalysis,energy storage,and so *** realize these practical applications,high-quality and large-area MoS2 with controllable properties is *** the many different synthesis techniques,epitaxy provides a promising route for producing MoS2 ***,we review the epitaxial growth of monolayer MoS2 on various substrates,with a particular focus on large-scale films with large domain sizes and high domain ***,we offer perspectives and challenges for future research and applications of this technology.

关键词： monolayer MoS_(2) epitaxy domain size domain alignment heterostructures

我国儿童药研制的制约因素分析及政策建议——基于医药企业的视角

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中国卫生政策研究 2024年第2期17卷 59-65页

作者：丁瑞琳白铭钰付佳男李新宇邵蓉中国药科大学药品监管科学研究院/国家药品监督管理局药品监管创新与评价重点实验室江苏南京211198

目的:为完善我国儿童药供应保障政策提供依据。方法:基于医药企业视角通过文献综述、问卷调研梳理药品全生命周期中儿童药研制的制约因素,分析其集中和迫切程度。结果:儿童药的主要制约因素包括:儿童临床试验开展难度大;注册审批规则中... 详细信息

目的:为完善我国儿童药供应保障政策提供依据。方法:基于医药企业视角通过文献综述、问卷调研梳理药品全生命周期中儿童药研制的制约因素,分析其集中和迫切程度。结果:儿童药的主要制约因素包括:儿童临床试验开展难度大;注册审批规则中缺乏对儿童药特殊性的考虑和专门的材料要求;生产激励政策落地缺乏实施细则和措施;市场利益机制尚不完善等。其中,研发和使用支付是问题相对集中的环节。讨论及建议:建议我国开拓并合理使用儿童临床试验资源,多举措增加儿童药研发投入;制定儿童药申报的专项指南,鼓励成人药品注册时提交儿童研究计划;基于典型案例探索儿童药生产供应优化路径;在药品使用与支付规则中给予儿童药更多空间。

关键词：医药企业儿童药研制制约因素政策