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The ALMA-QUARKS Survey.Ⅰ.Survey Description and Data Reduction

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Research in Astronomy and Astrophysics 2024年第2期24卷 104-124页

作者：刘训川 Tie liu Lei Zhu Guido Garay hong-li liu Paul Goldsmith Neal Evans Kee-Tae Kim sheng-Yuan liu Fengwei Xu Xing Lu Anandmayee Tej Xiaofeng Mai Leonardo Bronfman Shanghuo li Diego Mardones Amelia Stutz Ken'ichi Tatematsu Ke Wang Qizhou Zhang sheng-li Qin Jianwen zhou Qiuyi Luo Siju Zhang Yu Cheng Jinhua He Qilao Gu Ziyang li Zhenying Zhang Suinan Zhang Anindya Saha Lokesh Dewangan Patricio Sanhueza Zhiqiang Shen Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China Chinese Academy of Sciences South America Center for Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China Departamento de Astronomía Universidad de ChileLas Condes7591245 SantiagoChile school of Physics and Astronomy Yunnan UniversityKunming 650091China jet propulsion Laboratory California Institute of Technology4800 Oak Grove DrivePasadena CA 91109USA Department of Astronomy The University of Texas at AustinTX 78712-1205USA Korea Astronomy and Space Science Institute 776 Daedeokdae-roYuseong-guDaejeon 34055Republic of Korea Institute of Astronomy and Astrophysics Academia SinicaRoosevelt RoadTaipei 10617China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China Indian Institute of Space Science and Technology Thiruvananthapuram 695547KeralaIndia Max Planck Institute for Astronomy Königstuhl 17D-69117 HeidelbergGermany Departamento de Astronomía Universidad de ConcepciónCasilla 160-CConcepciónChile Nobeyama Radio Observatory National Astronomical Observatory of JapanNational Institutes of Natural Sciences462-2 NobeyamaMinamimakiMinamisakuNagano 384-1305Japan Center for Astrophysics∣Harvard&Smithsonian 60 Garden StreetCambridgeMA 02138USA Max-Planck-Institut für Radioastronomie Auf dem Hügel 69D-53125 BonnGermany school of Astronomy and Space Sciences University of Chinese Academy of SciencesBeijing 100049China National Astronomical Observatory of Japan 2-21-1 OsawaMitakaTokyo181-8588Japan Yunnan Observatories Chinese Academy of SciencesKunming 650216China Physical Research Laboratory NavrangpuraAhmedabad-380009India Astronomical Science Program The Graduate University for Advanced StudiesSOKENDAI2-21-1 OsawaMitakaTokyo 181-8588Japan university of Science and Technology Korea(UST)217 Gajeong-roYuseong-guDaejeon 34113Republic o

This paper presents an overview of the QUARKS survey,which stands for Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures."The QUARKS survey is observing13. massive clumps covered by 156 pointings at Atacama Large Millimeter/submillimeter Array(ALMA)Band 6(λ~1.3.mm).In conjunction with data obtained from the ALMA-ATOMS survey at Band 3.λ~3.mm),QUARKS aims to carry out an unbiased statistical investigation of massive star formation process within protoclusters down to a scale of 1000 *** overview paper describes the observations and data reduction of the QUARKS survey,and gives a first look at an exemplar source,the mini-starburst Sgr B2(M).The wide-b and width(7.5 GHz)and high-angular-resolution(~0."3.observations of the QUARKS survey allow for the resolution of much more compact cores than those could be done by the ATOMS survey,and to detect previously unrevealed fainter filamentary *** spectral windows cover transitions of species including CO,SO,N_(2)D^(+),SiO,H_(3.)α,H_(2)CO,CH_(3.CN,and many other complex organic molecules,tracing gas components with different temperatures and spatial *** aims to deepen our understanding of several scientific topics of massive star formation,such as the mass transport within protoclusters by(hub-)filamentary structures,the existence of massive starless cores,the physical and chemical properties of dense cores within protoclusters,and the feedback from already formed high-mass young protostars.

关键词： stars formation-stars kinematics and dynamics-ISM clouds-ISM molecules

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分布式动力翼-诱导翼面推进-气动耦合模型

航空学报 2024年第10期45卷 145-159页

作者：赵清风周洲李明浩徐德西北工业大学航空学院西安710072 西北工业大学计算机学院西安710072

针对分布式动力垂直起降飞行器,提出了综合理论模型和工程经验假设的分布式动力翼-诱导翼面布局的推进-气动耦合模型,实现了对垂起-过渡-巡航全飞行包线内分布式动力翼-诱导翼面气动性能的实时快速计算。结合涵道流场模型和涵道推力增... 详细信息

针对分布式动力垂直起降飞行器,提出了综合理论模型和工程经验假设的分布式动力翼-诱导翼面布局的推进-气动耦合模型,实现了对垂起-过渡-巡航全飞行包线内分布式动力翼-诱导翼面气动性能的实时快速计算。结合涵道流场模型和涵道推力增强系数发展了涵道喷流速度的快速计算方法,针对有/无动力输入状态完成了基于动量理论的推进-气动耦合模型推导,进行了推进-气动耦合模型特性分析,并开展了典型飞行工况下的CFD仿真校验与分析。结果表明,所建立的分布式动力翼-诱导翼面的推进-气动耦合模型具有较高精度,计算速度很快,能够满足动力学系统分析和飞行控制系统设计时的实时计算需求。

关键词：分布式电推进飞行器推进-气动耦合分布式动力翼诱导翼面动力学建模

射流放大器的不对称性对偏转板伺服阀零偏的影响

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阀门 2024年第2期 154-161页

作者：张晓博葛声宏邹小舟原佳阳李双路訚耀保江苏省机械行业协会江苏南京210000 中航工业南京伺服控制系统有限公司江苏南京210061 南京航空航天大学机电学院江苏南京210016 同济大学机械与能源工程学院上海201804

针对偏转板伺服阀前置级放大器结构不对称导致零偏的问题,考虑两个接收腔结构尺寸不一致以及劈尖相对射流口不对称等因素,基于二维紊动射流理论建立了偏导射流放大器压力特性数学模型,分析了两个接收腔圆角、内角、喉部宽度不一致性以... 详细信息

针对偏转板伺服阀前置级放大器结构不对称导致零偏的问题,考虑两个接收腔结构尺寸不一致以及劈尖相对射流口不对称等因素,基于二维紊动射流理论建立了偏导射流放大器压力特性数学模型,分析了两个接收腔圆角、内角、喉部宽度不一致性以及劈尖相对射流口的偏移量对放大器压力特性以及零偏位移的影响。分析结果表明:由于接收腔圆角和接收腔宽度直接决定射流流出接收腔的面积,故接收腔圆角和宽度的不对称会对放大器零件产生较大影响,两接收腔圆角差值每增大10μm,会近似产生0.3.μm的零偏,而两接收腔宽度差值每增大10μm,会近似产生1μm的零偏,接收孔内角的对称性和劈尖相对射流口的偏移则对放大器的零偏影响很小。减小两接收孔圆角和宽度的加工公差可以显著降低射流放大器的零偏,并提高射流放大器的一致性。

关键词：偏转板伺服阀射流放大器不对称性数学模型零偏

Numerical analysis and optimization of the inlet stage of a multi-stage high pressure compressor

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航空动力学报 2007年第8期22卷 1356-1364页

作者： XU Quan-yong HOU An-ping XIONG Jin-song zhou sheng National Key Laboratory on Aero-engines School of Jet Propulsion Beijing University of Aeronautics and Astronautics Beijing 100083

An opti mization process is used to redesign blades of a high-pressure *** artificial neural network (ANN) method is coupled to Navier-Stokes solvers and is applied to three different redesigns.A newrotor blade of a transonic compressor is designed by modifying thick,stacking line andinlet angle using a 3.approach,with a significant efficiencyi mprovement at the design *** off-design behavior of this new compressor is also checked afterwards,which shows that the whole performance of the inlet stage is improved over a wide range of mass *** losses are reduced,proving the good performance of the opti *** whole results indicate that the opti mization method can find i mproved design and can be integrated in a design procedure.

关键词：数学分析最优化航天推进系统高压压缩机人工神经网络叶栅

LAMOST/HRS spectroscopic analysis of two new li-rich giants

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Research in Astronomy and Astrophysics 2021年第1期21卷 198-206页

作者： Ze-Ming zhou Jian-Rong Shi hong-liang Yan Yong-Hui Hou Kai Zhang Qi Gao Xiao-Dong Xu Hai-Long Yuan Yu-Tao zhou Kaike Pan Zi-Ye Sang Yong-Heng Zhao CAS Key Laboratory of Optical Astronomy National Astronomical ObservatoriesChinese Academy of ScienceBeijing 100101China school of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Nanjing Institute of Astronomical Optics&Technology National Astronomical ObservatoriesChinese Academy of SciencesNanjing 210042China Department of Astronomy Peking UniversityBeijing 100871China Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Apache Point Observatory SunspotNew Mexico 88349USA Astronomy Department New Mexico State UniversityLas CrucesNew Mexico 88003USA

Two li-rich candidates,TYC 13.8-1410-1 and TYC 2825-596-1,were observed by the new high-resolution echelle spectrograph,LAMOST/*** on their high-resolution and high-signal-tonoise ratio(SNR)spectra,we derived stellar parameters and abundances of 14 important elements for the two *** stellar parameters and lithium abundances indicate that they are li-rich K-type giants,and having A(li)NLTE and 2.91 dex,*** analysis suggests that TYC 13.8-1410-1 is probably a red giant branch(RGB)star at the bump stage,while TYC 2825-596-1 is most likely to be a core helium-burning red clump(RC)*** line profiles of both spectra indicate that the two li-rich giants are slow rotators and do not show infrared(IR)*** conclude that engulfment is not the lithium enrichment mechanism for either *** enriched lithium of TYC 13.8-1410-1 could be created via the Cameron-Fowler mechanism,while the lithium excess in TYC 2825-596-1 could be associated with either non-canonical mixing processes or He-flash.

关键词： stars:fundamental parameters stars:late-type stars:low-mass stars:abundances stars:chemically peculiar

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微小尺度通道内超临界甲烷传热特性研究

南京航空航天大学学报 2021年第4期53卷 513-520页

作者：李辉汝卓霖邹正平周双钊北京航空航天大学能源与动力工程学院航空发动机气动热力国家级重点实验室北京100191 中国航空发动机研究院先进航空动力创新站北京101304 北京航空航天大学航空发动机研究院北京100191

研究微小尺度通道内超临界甲烷的传热特性对于碳氢燃料预冷器精细化设计具有重要意义。本文利用实验方法探究了热流密度、质量流量以及系统压力等边界条件对微细圆管内超临界甲烷传热特性的影响规律,并结合数值方法分析了跨临界传热强... 详细信息

研究微小尺度通道内超临界甲烷的传热特性对于碳氢燃料预冷器精细化设计具有重要意义。本文利用实验方法探究了热流密度、质量流量以及系统压力等边界条件对微细圆管内超临界甲烷传热特性的影响规律,并结合数值方法分析了跨临界传热强化的主要原因。结果表明:在实验工况范围内,当超临界甲烷温度接近拟临界温度时均产生了不同程度的传热强化现象,且质量流量和系统压力变化对换热系数峰值的影响更大。传热强化产生的原因主要有两点,一是在拟临界点附近较大的径向密度梯度导致了浮升力的产生,进而在浮升力和重力的共同作用下生成二次流,增强了流体掺混;二是此处的超临界甲烷定压比热急剧增加,增强了自身的载热能力。最终,根据实验结果提出了适用于微细圆管内超临界甲烷对流换热预测的经验关联式,以期为碳氢燃料预冷器精细化设计提供模型依据。

关键词：传热超临界流体甲烷微细圆管