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J-comb: An image fusion algorithm to combine observations covering different spatial frequency ranges

Science China(Physics,Mechanics & Astronomy) 2022年第9期65卷 138-156页

作者： sihan jiao Yuxin Lin Xiangyu Shui Jingwen Wu Zhiyuan Ren Di Li National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Centre for Astrochemical Studies Max-Planck-Institut f¨ur Extraterrestrische PhysikGarching 85748Germany Astrophysics Department Munich UniversityMunich 81679Germany NAOC-UKZN Computational Astrophysics Centre University of KwaZulu-NatalDurban 4000South Africa

Ground-based, high-resolution bolometric(sub)millimeter continuum mapping observations on spatially extended target sources are often subject to significant missing fluxes. This hampers accurate quantitative analyses. Missing flux can be recovered by fusing high-resolution images with observations that preserve extended structures. However, the commonly adopted image fusion approaches do not maintain the simplicity of the beam response function and do not try to elaborate the details of the yielded beam response functions. These make the comparison of the observations at multiple wavelengths not straightforward. We present a new algorithm, J-comb, which combines the high and low-resolution images linearly. By applying a taper function to the low-pass filtered image and combining it with a high-pass filtered image using proper weights, the beam response functions of our combined images are guaranteed to have near-Gaussian shapes. This makes it easy to convolve the observations at multiple wavelengths to share the same beam response functions. Moreover, we introduce a strategy to tackle the specific problem that the imaging at 850 μm from the present-date ground-based bolometric instrument and that taken with the Planck satellite do not overlap in the Fourier domain. We benchmarked our method against two other widely-used image combination algorithms, CASA-feather and MIRIAD-immerge, with mock observations of star-forming molecular clouds. We demonstrate that the performance of the J-comb algorithm is superior to those of the other two algorithms. We applied the J-comb algorithm to real observational data of the Orion A star-forming region. We successfully produced dust temperature and column density maps with ~10′′angular resolution, unveiling much greater details than the previous results. A py Thon code release of J-comb and implementation of the algorithm are available at https://***/sihan jiao/J-comb.

关键词： star formation molecular clouds image processing

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Can Turbulent, High-density Gas Form Stars in Molecular Clouds: A Case Study in Ophiuchus

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Research in Astronomy and Astrophysics 2022年第7期22卷 235-243页

作者： sihan jiao Jingwen Wu Hao Ruan Yuxin Lin Chao-Wei Tsai Linjing Feng National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Centre for Astrochemical Studies Max-Planck-Institut für Extraterrestrische PhysikGießenbachstraße 1D-85748 GarchingGermany

Star formation is governed by the interplay between gravity and turbulence in most of molecular *** theoretical works assume that dense gas,whose column density is above a critical value in the column density probability distribution function(N-PDF),where gravity starts to overcome turbulence,becomes star-forming gas and will collapse to form ***,these high-density gases will include some very turbulent areas in the *** these dense but turbulent gases also form stars?We test this scenario in Ophiuchus molecular cloud using N-PDF analysis and find that at least in some regions,the turbulent,dense gas is not forming *** identified two isolated high-density structures in Ophiuchus,which are gravitationally unbound and show no sign of star *** high densities may come from turbulence.

关键词： ISM:clouds stars:formation ISM:structure

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The Distribution of UV Radiation Field in the Molecular Clouds of Gould Belt

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Research in Astronomy and Astrophysics 2022年第8期22卷 206-217页

作者： Jifeng Xia Ningyu Tang Qijun Zhi sihan jiao Jinjin Xie Gary A.Fuller Paul F.Goldsmith Di Li School of Physics and Electronic Science Guizhou Normal UniversityGuiyang 550025China National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Department of Physics Anhui Normal UniversityWuhu 241002China Guizhou Provincial Key Laboratory of Radio Astronomy and Data Processing Guizhou Normal UniversityGuiyang 550001China Shanghai Astronomical Observatory CASShanghai 200030China Jodrell Bank Centre for Astrophysics Department of Physics&AstronomyThe University of ManchesterManchester M139PLUnited Kingdom I.Physikalisches Institut University of CologneZülpicher Str.77D-50937 KölnGermany Jet Propulsion Laboratory California Institute of Technology4800 Oak Grove DrivePasadenaCA 91109United States of America

The distribution of ultraviolet(UV)radiation field provides critical constraints on the physical environments of molecular *** 1 kpc of our solar system and fostering protostars of different masses,the giant molecular clouds in the Gould Belt present an excellent opportunity to resolve the UV field structure in star-forming *** performed spectral energy distribution(SED)fitting of the archival data from the Herschel Gould Belt Survey(HGBS).Dust radiative transfer analysis with the DUSTY code was applied to 23 regions in 14 molecular complexes of the Gould Belt,resulting in the spatial distribution of the radiation field in these *** 10 of 15 regions with independent measurements of star formation rate,their star formation rate and UV radiation intensity largely conform to a linear correlation found in previous studies.

关键词： ISM:clouds (ISM:)dust extinction radiative transfer

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Optical Extinctions of Inter-Arm Molecular Clouds in M31:A Pilot Study for the Upcoming CSST Observations

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Research in Astronomy and Astrophysics 2024年第6期24卷 323-333页

作者： Cailing Chen Zheng Zheng Chao-Wei Tsai sihan jiao Jing Tang Jingwen Wu Di Li Yun Zheng Linjing Feng Yujiao Yang Yuan Liang National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China Key Laboratory of Radio Astronomy and Technology Chinese Academy of SciencesBeijing 100101China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China Zhejiang Lab Hangzhou 311121China

Recent submillimeter dust thermal emission observations have unveiled a significant number of inter-arm massive molecular clouds in ***,the effectiveness of this technique is limited to its sensitivity,making it challenging to study more distant *** study introduces an alternative approach,utilizing optical extinctions derived from space-based telescopes,with a focus on the forthcoming China Space Station Telescope(CSST).We first demonstrate the capability of this method by constructing dust extinction maps for 17 inter-arm massive molecular clouds in M31 using the Panchromatic Hubble Andromeda Treasury *** analysis reveals that inter-arm massive molecular clouds with an optical extinction(A_(V)) greater than 1.6 mag exhibit a notable A_(V) excess,facilitating their *** majority of these inter-arm massive molecular clouds show an A_(V) around 1 mag,aligning with measurements from our JCMT *** validation using a mock CSST RGB star catalog confirms the method's *** show that the derived A_(V)values using CSST z and y photometries align more closely with the input *** clouds with A_(V)> 1.6 mag can also be identified using the CSST mock *** thus claim that future CSST observation clouds provide an effective way for the detection of inter-arm massive molecular clouds with significant optical extinction in nearby galaxies.

关键词： infrared:stars ISM:clouds Galaxy:structure

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The ALMaQUEST Survey ⅩⅤ:The dependence of the molecular-to-atomic gas ratios on resolved optical diagnostics

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Science China(Physics,Mechanics & Astronomy) 2024年第9期67卷 174-196页

作者： Niankun Yu Zheng Zheng Chao-Wei Tsai Pei Zuo Sara L.Ellison David V.Stark Di Li Jingwen Wu Karen L.Masters Ting Xiao Yinghui Zheng Zongnan Li Kai Zhang Hongying Chen Shu Liu sihan jiao Fanyi Meng National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China Key Laboratory of Radio Astronomy and Technology Chinese Academy of SciencesBeijing 100101China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing 102206China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Department of Physics&Astronomy University of VictoriaVictoriaV8P 1A1Canada Departments of Physics and Astronomy Haverford CollegeHaverford19041USA Space Telescope Science Institute San Martin Dr.Baltimore 21218USA Zhejiang Laboratory Hangzhou 311121China New Cornerstone Science Laboratory Shenzhen 518054China School of Physics Zhejiang UniversityHangzhou 310058China

The atomic-to-molecular gas conversion is a critical step in the baryon cycle of galaxies,which sets the initial conditions for subsequent star formation and influences the multi-phase interstellar *** compiled a sample of 94 nearby galaxies with observations of multi-phase gas contents by utilizing public H_(Ⅰ),CO,and optical IFU data from the Ma NGA survey together with new FAST H_(Ⅰ)*** agreement with previous results,our sample shows that the global molecular-to-atomic gas ratio(R_(mol)≡log M_(H2)/M_(H_(Ⅰ)))is correlated with the global stellar mass surface densityμ_*with a Kendall'sτcoefficient of 0.25 and p<10^(-3),less tightly but still correlated with stellar mass and NUV-r color,and not related to the specific star formation rate(sSFR).The cold gas distribution and kinematics inferred from the H_(Ⅰ)and CO global profile asymmetry and shape do not significantly rely on R_(mol).Thanks to the availability of kpc-scale observations of MaNGA,we decompose galaxies into H_(Ⅱ),composite,and AGN-dominated regions by using the BPT *** increasing R_(mol),the fraction of H_(Ⅱ)regions within 1.5 effective radius decreases slightly;the density distribution in the spatially resolved BPT diagram also changes significantly,suggesting changes in metallicity and ionization *** with high R_(mol)tend to have high oxygen abundance,both at one effective radius with a Kendall'sτcoefficient of 0.37(p<10^(-3))and their central *** all parameters investigated here,the oxygen abundance at one effective radius has the strongest relation with global R_(mol).The dependence of gas conversion on gas distribution and galaxy ionization states is *** contrast,the observed positive relation between oxygen abundance(μ_(*))and R_(mol)indicates that the gas conversion is efficient in regions of high metallicity(density).

关键词： Galaxies baryon cycle radio lines H_(Ⅰ)21 cm atomic-to-molecular gas conversion

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从《黄帝内经》论风湿病的中医护理特色

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中国中医药现代远程教育 2023年第2期21卷 81-83页

作者：焦思涵于志谋北京市石景山区中医医院医务科北京100043

风湿病是一种顽固的累及全身多脏腑系统的慢性结缔组织疾病,病程久,易反复发作,所以对风湿病的护理不能忽视。《黄帝内经》提出了风湿病中医护理要求和理论基础,文章依据中医治未病的理论,通过情志、饮食、导引锻炼及四季调护等方面对... 详细信息

风湿病是一种顽固的累及全身多脏腑系统的慢性结缔组织疾病,病程久,易反复发作,所以对风湿病的护理不能忽视。《黄帝内经》提出了风湿病中医护理要求和理论基础,文章依据中医治未病的理论,通过情志、饮食、导引锻炼及四季调护等方面对风湿病的护理进行总结,将使风湿病的护理更加具体实效,达到事半功倍的效果。

关键词：《黄帝内经》风湿病痹证中医护理

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The ALMA-QUARKS Survey.Ⅱ.The ACA 1.3 mm Continuum Source Catalog and the Assembly of Dense Gas in Massive Star-Forming Clumps

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Research in Astronomy and Astrophysics 2024年第6期24卷 119-139页

作者：许峰玮 Ke Wang Tie Liu Lei Zhu Guido Garay Xunchuan Liu Paul Goldsmith Qizhou Zhang Patricio Sanhueza Shengli Qin Jinhua He Mika Juvela Anandmayee Tej Hongli Liu Shanghuo Li Kaho Morii Siju Zhang Jianwen Zhou Amelia Stutz Neal JEvans Kee-Tae Kim Shengyuan Liu Diego Mardones Guangxing Li Leonardo Bronfman Ken’ichi Tatematsu Chang Won Lee Xing Lu Xiaofeng Mai sihan jiao James O.Chibueze Keyun Su Viktor L.Tóth Kavli Institute for Astronomy and Astrophysics Peking UniversityBeijing 100871China Department of Astronomy School of PhysicsPeking UniversityBeijing 100871China 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 Jet Propulsion Laboratory California Institute of Technology4800 Oak Grove DrivePasadena CA 91109USA Center for Astrophysics|Harvard&Smithsonian 60 Garden StreetCambridgeMA 02138USA National Astronomical Observatory of Japan National Institutes of Natural Sciences2-21-1 OsawaMitakaTokyo 181-8588Japan Astronomical Science Program The Graduate University for Advanced StudiesSOKENDAI2-21-1 OsawaMitakaTokyo 181-8588Japan School of Physics and Astronomy Yunnan UniversityKunming 650091China Yunnan Observatories Chinese Academy of SciencesKunming 650216China Department of Physics University of HelsinkiPO Box 64FI-00014 HelsinkiFinland Indian Institute of Space Science and Technology Thiruvananthapuram 695547KeralaIndia Max Planck Institute for Astronomy Königstuhl 17D-69117 HeidelbergGermany Department of Astronomy Graduate School of ScienceThe University of Tokyo7-3-1 HongoBunkyo-kuTokyo 113-0033Japan Max-Planck-Institut für Radioastronomie Auf dem Hügel 6953121 BonnGermany Departamento de AstronomÂıa Universidad de ConcepcionCasilla 160-CConcepci onChile Department of Astronomy The University of Texas at AustinTexas 78712-1205USA Korea Astronomy and Space Science Institute 776 Daedeokdae-roYuseong-guDaejeon 34055Republic of Korea Institute of Astronomy and Astrophysics Academia SinicaRoosevelt RoadTaipei 10617TaiwanChina South-Western Institute for Astronomy Research Yunnan UniversityKunming 650091China Korea Astronomy and Space Science Institute 776 Daedeok-daeroYuseong-guDaejeon 34055Republic of

Leveraging the high resolution,sensitivity,and wide frequency coverage of the Atacama Large Millimeter/submillimeter Array(ALMA),the QUARKS survey,standing for“Querying Underlying mechanisms of massive star formation with ALMA-Resolved gas Kinematics and Structures”,is observing 139 massive starforming clumps at ALMA Band 6(λ~1.3 mm).This paper introduces the Atacama Compact Array(ACA)7 m data of the QUARKS survey,describing the ACA observations and data *** multiwavelength data,we provide the first edition of QUARKS atlas,offering insights into the multiscale and multiphase interstellar medium in high-mass star *** ACA 1.3 mm catalog includes 207 continuum sources that are called ACA *** gas kinetic temperatures are estimated using three formaldehyde transitions with a non-LTE radiation transfer model,and the mass and density are derived from a dust emission *** ACA sources are massive(16–84 percentile values of 6–160 M_(⊙)),gravity-dominated(M∝R^(1.1))fragments within massive clumps,with supersonic turbulence(M>1)and embedded star-forming *** find a linear correlation between the masses of the fragments and the massive clumps,with a ratio of 6%between the *** considering fragments as representative of dense gas,the ratio indicates a dense gas fraction(DGF)of 6%,although with a wide scatter ranging from 1%to 10%.If we consider the QUARKS massive clumps to be what is observed at various scales,then the size-independent DGF indicates a self-similar fragmentation or collapsing mode in protocluster *** the ACA data over four orders of magnitude of luminosity-to-mass ratio(L/M),we find that the DGF increases significantly with L/M,which indicates clump evolutionary *** observed a limited fragmentation at the subclump scale,which can be explained by a dynamic global collapse process.

关键词： stars:formation ISM:kinematics and dynamics ISM:clouds stars:protostars

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石油钻井绞车滚筒旋向与钢丝绳捻向探析

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汽车实用技术 2021年第17期46卷 218-220页

作者：程立寇蓓焦思菡兰州兰石石油装备工程股份有限公司甘肃兰州730314

在石油钻采领域钻井绞车滚筒旋向与钢丝绳捻向的选配,一直存在较大的争议。文章简要介绍钻井钢丝绳常用类型及捻向,并对钻井绞车滚筒绳槽的特点和旋向进行分析。分别对单层缠绕和多层缠绕时滚筒旋向与钢丝绳捻向关系进行讨论。分析石油... 详细信息

在石油钻采领域钻井绞车滚筒旋向与钢丝绳捻向的选配,一直存在较大的争议。文章简要介绍钻井钢丝绳常用类型及捻向,并对钻井绞车滚筒绳槽的特点和旋向进行分析。分别对单层缠绕和多层缠绕时滚筒旋向与钢丝绳捻向关系进行讨论。分析石油钻采领域钻井工况下滚筒缠绕钢丝绳范围,提出滚筒旋向与钢丝绳捻向的选配观点。依供实际操作过程中正确选配钻井钢丝绳,减少架空、打扭、骑绳等现象,延长钻井钢丝绳使用周期。

关键词：钢丝绳捻向滚筒旋向

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Influence of different rolling processes on microstructure and strength of the Al–Cu–Li alloy AA2195

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Progress in Natural Science:Materials International 2022年第1期32卷 87-95页

作者： Fan Ye Ling Mao Jian Rong Baoshuai Zhang Lijun Wei sihan Wen Haojun jiao Sujun Wu International Research Center for Advanced Structural and Biomaterials School of Materials Science and Engineering Beihang University School of Materials Science and Engineering Beihang University Aerospace Research Institute of Materials & Processing Technology

The influence of different rolling processes on precipitation behaviour, crystallography texture, grain morphology,and their consequent effects on tensile properties for Al–Cu–Li alloy AA2195 was investigated in the present *** H-T8 samples(hot rolled + T8) presented better tensile strength and ductility(with serious strength anisotropy) than the HC-T8 samples(hot rolled + cold rolled + T8), due to their different microstructures and textures. The higher dislocation density was found in the H-T8 samples, which promoted the nucleation of main strengthening phase T1in the matrix and suppressed the grain boundary precipitation, resulted in better strength and ductility. The increase of the dynamic recovery(DRV) during hot rolling enhanced the generation of Brass texture, and brought serious strength anisotropy. The cold rolling was performed after the hot-rolling process for the HC-T8 samples which increased deformation energy and resulted in full recrystallization of the deformed microstructure during the following solution treatment. The formation of recrystallized microstructure reduced the dislocation density and the heterogeneous precipitate nucleation positions which limited the strengthening phase precipitation in matrix and accelerated the precipitation along grain boundaries, resulted in fewer T1precipitates, coarse grain-boundary precipitates(GBPs), and wider precipitate-free zones(PFZs). The localized strain may be concentrated on the grain boundary to induce the dislocation pile-up, breaking of the GBPs, and intergranular fracture during stretching.

关键词： Al-Cu-Li alloys Rolling Mechanical properties Microstructure evolution Fracture

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Regulating macrophage-MSC interaction to optimize BMP-2-induced osteogenesis in the local microenvironment

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Bioactive Materials 2023年第7期25卷 307-318页

作者： Fei Jiang Xuanyu Qi Xiaolin Wu sihan Lin Junfeng Shi Wenjie Zhang Xinquan Jiang Department of Prosthodontics Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineNo.639Zhizaoju RoadShanghai200011China College of Stomatology Shanghai Jiao Tong UniversityNational Center for StomatologyNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of StomatologyShanghai Engineering Research Center of Advanced Dental Technology and MaterialsNo.639Zhizaoju RoadShanghai200011China Jiangsu Key Laboratory of Oral Diseases Jiangsu Province Engineering Research Center of Stomatological Translational MedicineNanjing Medical UniversityNo.140Han Zhong RoadNanjing210029China Department of General Dentistry Affiliated Hospital of StomatologyNanjing Medical UniversityNo.136Han Zhong RoadNanjing210029China

Bone morphogenetic protein(BMP-2)has been approved by the FDA to promote bone regeneration,but uncertain osteogenic effect and dose-dependent side effects may *** plays an important role in growth factor-based ***,we explored how proinflammatory signals affect the dose-dependent osteogenic potential of *** observed that the expression level of local IL-1βdid not increase with the dose of BMP-2 in the mouse osteogenesis model.A low dose of BMP-2 could not promote new bone formation,but trigger the release of IL-1βfrom M1 *** the dose of BMP-2 increased,the IL-1βexpression and M1 infiltration in local microenvironment were inhibited by IL-1Ra from MSCs under osteogenic differentiation induced by BMP-2,and new bone tissues formed,even ***-inflammatory drugs(Dexamethasone,Dex)promoted osteogenesis via inhibiting M1 polarization and enhancing BMP-2-induced MSC ***,we suggest that the osteogenic effect of BMP-2 involves macrophage-MSC interaction that is dependent on BMP-2 dose and based on IL-1R1 ligands,including IL-1βand *** dose of BMP-2 could be reduced by introducing immunoregulatory strategies.

关键词： BMP-2 Osteogenesis IL-1β IL-1Ra Macrophage-MSC interaction

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