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Research in Astronomy and Astrophysics 2022年第8期22卷 125-139页

作者： Yining Zhang Jing Ye zhixing Mei Yan Li Jun Lin Yunnan Observatories Chinese Academy of SciencesKunming 650216China University of Chinese Academy of Sciences Beijing 100049China Center for Astronomical Mega-Science Chinese Academy of SciencesBeijing 100101China

We attempt to model magnetic reconnection during the two-ribbon flare in a gravitationally stratified solar atmosphere with the Lundquist number of S=10~6 using 2 D simulations.We found that the tearing mode instability leads to inhomogeneous turbulence inside the reconnecting current sheet(CS)and invokes the fast phase of reconnection.Fast reconnection brings an extra dissipation of magnetic field which enhances the reconnection rate in an apparent way.The energy spectrum in the CS shows a power law pattern and the dynamics of plasmoids govern the associated spectral index.We noticed that the energy dissipation occurs at a scale l_(ko)of 100-200 km,and the associated CS thickness ranges from 1500 to 2500 km,which follows the Taylor scale l_(T)=l_(ko)S_(1/6).The termination shock(TS)appears in the turbulent region above flare loops,which is an important contributor to heating flare loops.Substantial magnetic energy is converted into both kinetic and thermal energies via TS,and the cumulative heating rate is greater than the rate of the kinetic energy transfer.In addition,the turbulence is somehow amplified by TS,in which the amplitude is related to the local geometry of the TS.

关键词： magnetic reconnection magnetohydrodynamics(MHD) Sun:flares turbulence

Numerical experiments of disturbance to the solar atmosphere caused by eruptions

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Science China(Physics,Mechanics & Astronomy) 2012年第7期55卷 1316-1329页

作者： mei zhixing UDO Ziegler LIN Jun Yunnan Astronomical Observatory Chinese Academy or'SciencesP.O.Box 110Kunming 650011China Graduate University of the Chinese Academy of Sciences Beijing 100049China Leibniz-lnstitut filer A strophysik Potsdam Potsdam D-14482Germany Harvard-Smithsonian Center for Astrophysics 60 Garden StreetCambridge 02138USA

Despite extensive research on various global waves in solar eruptions, debate continues on the intrinsic nature of them. In this work, we performed numerical experiments of the coronal mass ejection with emphases on the associated large-scale MHD waves. A fast-mode shock forms in front of the flux rope during the eruption with a dimming region following it, and the development of a three-component structure of the ejecta is observed. At the flank of the flux rope, the slow-mode shock and the velocity vortices are also invoked. The dependence of the eruption energetics on the strength of the background field and the coronal plasma density distribution is apparent: the stronger the background field is, and/or the lower the coronal plasma density is, the more energetic the eruption is. In the lower Alfve′n speed environment, the slow mode shock and the large scale velocity vortices may be the source of the EIT wave. In the high Alfve′n speed environment, on the other hand, the echo due to the reflection of the fast shock on the bottom boundary could be so strong that its interaction with the slow mode shock and the velocity vortices produces the second echo propagating downward and causing the secondary disturbance to the boundary surface. We suggest that this second echo, together with the slow shock and the velocity vortices, could constitute a possible candidate of the source for the EIT wave.

关键词：火山喷发太阳爆发数值试验大气干扰日冕物质抛射等离子体密度企业所得税密度分布

Overexpression of sigma-1 receptor inhibits ADAM10 and ADAM17 mediated shedding in vitro

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Protein & Cell 2012年第2期3卷 400-400页

作者： Juan Li Bin Liu Xiaofei Gao zhixing Ma Tianyi CaoSong Yan-ai mei Yufang Zheng School of Life Sciences Fudan UniversityShanghai 200433China

Erratum to:Protein Cell 2012,3(2):153-159 DOI 10.1007/s13238-012-2006-9 Two mistakes in Fig.3A and 4A,respectively,were made due to typesetting errors.Figure 3A,on the left column of page 156,should be cor-rected as f... 详细信息

关键词： Figure cor ADAM10

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杭州雨水花园植物应用现状研究

南京林业大学学报（自然科学版） 2022年第4期46卷 239-246页

作者：武文婷周婷婷任彝梅欹李智兴浙江工业大学设计与建筑学院浙江杭州310023 杭州爱田网络科技有限公司浙江杭州310051

【目的】运用实地调研法,针对已建成的城市雨水花园项目,从植物资源应用的角度进行多指标调查评价,分析存在的问题,为相关研究提供参考。【方法】依据杭州市雨水花园分布情况,选取17个代表性雨水花园,从植物资源的总体应用现状、植物观... 详细信息

【目的】运用实地调研法,针对已建成的城市雨水花园项目,从植物资源应用的角度进行多指标调查评价,分析存在的问题,为相关研究提供参考。【方法】依据杭州市雨水花园分布情况,选取17个代表性雨水花园,从植物资源的总体应用现状、植物观赏特性、不同场地植物种数及结构模式、不同雨水处理区植物生态特性和种类等方面进行研究。【结果】①雨水花园灌木和草本的种类较多,草本植物数量最多,乔木应用较少;②在蓄水区以耐干旱、耐水湿、抗污染能力及净化能力强的植物为主,在缓冲区以较耐干旱、耐短期水湿及抗雨水冲刷能力强的植物为主,在边缘区以较耐干旱、较耐水湿的植物为主;③植物有66种,隶属于36科51属,被子植物种类最多,占比在90%以上;④应用较多的主要有禾本科、蔷薇科、莎草科、杉科、豆科植物;⑤草本植物以多年生为主,灌木的常绿和落叶比例相差不大,乔木以落叶植物为主;⑥观花植物占比最大(53.03%),色系较丰富,其中紫色系和白色系植物最多。【结论】杭州市雨水花园植物资源总体应用现状良好,但也存在部分问题有待改进。本研究将为雨水花园植物资源的应用和优化提供启示和借鉴。

关键词：城市绿地雨水花园植物资源应用现状优化策略杭州市

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超声误诊腮腺区卡斯尔曼病1例

中国医学影像技术 2020年第8期36卷 1271-1271页

作者：黄梅刘志兴陈莉南昌大学第一附属医院超声科江西南昌330006

患者女,37岁,因"发现右侧耳下无痛性包块1年余、增大1周"就诊。查体:右侧耳下可触及4cm×3cm肿物,质韧,无压痛,边缘光滑;右侧腮腺导管口未见明显充血及异常分泌物。超声:右侧腮腺浅叶可探及约3.8cm×1.6cm低回声团,形态规则,边界清晰,... 详细信息

患者女,37岁,因"发现右侧耳下无痛性包块1年余、增大1周"就诊。查体:右侧耳下可触及4cm×3cm肿物,质韧,无压痛,边缘光滑;右侧腮腺导管口未见明显充血及异常分泌物。超声:右侧腮腺浅叶可探及约3.8cm×1.6cm低回声团,形态规则,边界清晰,边缘光整,内部回声尚均匀(图1A);CDFI:肿物内部见多支粗大血管穿入及大量散在点状血流信号,动脉血流频谱呈低阻型(图1B);提示腮腺淋巴瘤?行腮腺肿物切除术+腮腺浅叶切除术+周围神经松解术,术中右侧腮腺浅叶未见明确肿瘤,乃切除腮腺浅叶送检,并松解周围神经。

关键词：卡斯尔曼病腮腺超声检查

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基于OBE的“材料科学基础实验”教学改革

实验室科学 2022年第2期25卷 137-140页

作者：郭智兴杨梅鲜广熊计四川大学机械工程学院四川成都610065 成都理工大学材料与化学化工学院四川成都610059

针对目前“材料科学基础实验”教学中存在的问题,提出基于OBE理念的教学改革。从知识、技能和能力三个层次定义了预期学习成果,对教学策略进行反向设计并采用阶梯型实验教学、团队教学和开放教学等方式确保学习目标实现,进行了基于过程... 详细信息

针对目前“材料科学基础实验”教学中存在的问题,提出基于OBE理念的教学改革。从知识、技能和能力三个层次定义了预期学习成果,对教学策略进行反向设计并采用阶梯型实验教学、团队教学和开放教学等方式确保学习目标实现,进行了基于过程的多元化能力评价,并利用评价结果进行持续改进。基于OBE理念的教学改革可提高学生的工程实践能力,为工科实验教学改革提供了参考。

关键词： OBE理念材料科学基础实验教学学习成果

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地表沉陷预计参数精度分析

测绘科学 2016年第8期41卷 33-37页

作者：刘伟韬刘欢陈志兴李媚山东科技大学矿业与安全工程学院山东青岛266590 南京师范大学虚拟地理环境教育部重点实验室南京210023

针对开采沉陷预计参数的误差造成预计结果偏差的问题,该文提出一种研究开采沉陷预计参数精度的方法。在真值基础上,将预计参数按照0.5%的步距增大和减小后分别预计地表下沉值,分析得出预计参数的误差会对预计结果造成的偏差;通过反分析... 详细信息

针对开采沉陷预计参数的误差造成预计结果偏差的问题,该文提出一种研究开采沉陷预计参数精度的方法。在真值基础上,将预计参数按照0.5%的步距增大和减小后分别预计地表下沉值,分析得出预计参数的误差会对预计结果造成的偏差;通过反分析得出测量误差对预计参数产生的影响。实验结果表明:预计参数每变化0.5%,下沉值中误差占最大下沉值的0.8%,且倾向方向的下沉值中误差是走向方向下沉值中误差的两倍;下沉值测量中误差与预计参数误差之间成线性关系。研究结果为测量时的精度控制提供了依据,从而为预测计算提供可靠的预计参数。

关键词：开采沉陷移动变形中误差预计参数精度

基于保温结构一体化系统的建筑生命周期碳排放研究

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建筑科学 2023年第4期39卷 26-34页

作者：罗智星于运星卢梅王海宁陈畅赵楠西部绿色建筑国家重点实验室西安710055 西安建筑科技大学建筑学院西安710055 西安建筑科技大学管理学院西安710055 东南大学建筑学院南京211189 西安建筑科技大学材料科学与工程学院西安710055 西安建筑科技大学土木工程学院西安710055

保温结构一体化系统凭借其热工性能、与建筑同寿命等优势,可使建筑在一定程度上减少碳排放。本研究结合生命周期评价理论,选定保温结构一体化产物——增强复合岩棉条板保温系统为研究对象,以1 m2为单位进行了生产阶段的碳排放计算,并以... 详细信息

保温结构一体化系统凭借其热工性能、与建筑同寿命等优势,可使建筑在一定程度上减少碳排放。本研究结合生命周期评价理论,选定保温结构一体化产物——增强复合岩棉条板保温系统为研究对象,以1 m2为单位进行了生产阶段的碳排放计算,并以西安市某住宅为例进行了与岩棉薄抹灰外保温系统的建筑生命周期碳排放核算与对比分析。结果表明,采用保温结构一体化系统的建筑可减少约1.61%,即30.5 kgCO_(2)e/m^(2)的生命周期碳排放,同时可避免由于保温系统再次生产运输和施工所造成的人力物力的大量浪费,为建筑领域绿色发展做出显著贡献。

关键词：建筑碳排放保温结构一体化建筑外保温岩棉

ADAM17 is critical for multipolar exit and radial migration of neuronal intermediate progenitor cells in mice cerebral cortex

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ADAM17 is critical for multipolar exit and radial migration ...

Effect of VC addition on the microstructure and properties of Ti(C,N)-based nano cermets

中国神经科学学会第十届全国学术会议

作者： Qingyu Li Zhengyu Zhang Zengmin Li mei Zhou Bin Liu Le Pan zhixing Ma Yufang Zheng School of Life Sciences Fudan University

The radial migration of neuronal progenitor cells is critical for the development of cerebral cortex layers.They go through a critical step transforming from multipolar to bipolar before outward migration.A Disintegrin and Metalloprotease 17（ADAM17） is a transmembrane protease which can process many substrates involved in cell-cell interaction,including Notch,ligands of EGFR,and some cell adhesion molecules.In this study,we used in utero electroporation to knock down or overexpress ADAM17 at embryonic day 14.5（E14.5） in neuronal progenitor cells to examine the role of ADAM17 in cortical embryonic neurogenesis.Our results showed that the radial migration of ADAM17-knocked down cells were normal till E16.5 and reached the intermediate zone（IZ）.Then most transfected cells stopped migration and stayed at the IZ to inner cortical plate（CP） layer at E18.5,and there was higher percentage of multipolar cells at IZ layer in the ADAM17-knocked down group compared to the cells in control group.Marker staining revealed that those ADAM17-knocked down cells differentiated normally from neural stem cells（NSCs） to neuronal intermediate progenitor cells（nIPCs） but did not differentiate into mature neurons.The migration and multipolar exit defects caused by ADAM17 knockdown could be partially rescued by over-expressing an shRNA resistant ADAM17,while overexpressing ADAM17 alone did not affect the radial migration.Taken together,our results showed for the first time that,ADAM17 is critical in regulating the multipolar-stage exit and radial migration of the nIPCs during telencephalon cortex development in mice.

关键词： ADAM17 neuronal intermediate progenitor cells radial migration multipolar-stage exit cortex development

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Rare Metals 2011年第6期30卷 583-588页

作者： YING Xiayu XIONG Ji GUO zhixing CHEN Jianzhong XIONG Sujian YANG mei FAN Hongyuan School of Manufacturing Science and Engineering Sichuan University Chengdu 610065 China College of Materials and Chemistry ＆ Chemical Engineering Chengdu University of Technology Chengdu 610059 China

In this paper, Ti（C,N）-based nano cermets were prepared by nano particles, and the effect of VC addition on the micmstructure and properties of Ti（C,N）-based nano cermets was investigated. The results showed that there existed black-core grayish-rim strucmre as well as gray-core grayish-rim structure in VC-doped Ti（C,N）-based nano cermets. With the increase of VC addition, the number of gray cores in- creased, the lattice parameter of Ti（C,N） phase increased, the grain size decreased, the hardness and fracture toughness of Ti（C,N）-based nano cermets were enhanced, and nearly full densification could be achieved. However, excessive addition of VC to 1 wt% resulted in slight decrease in hardness and fracture toughness. Some deep dimples were found in the fracture surface of cermets with VC addition, which corresponded to ductile fracture.

关键词： powder metallurgy Ti（C,N）-based nano cermets VC addition microstructure properties