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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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滤材截留微粒中PAHs吹出效应之研究

过程工程学报 2004年第Z1期4卷 859-863页

作者：李经民井长瑞陈玉恭郑惠裕云林科技大学环境与安全研究所云林云林科技大学环境与安全研究所云林云林科技大学环境与安全研究所云林云林科技大学环境与安全研究所云林

滤材截留粒状物中因采集气流常造成固相PAHs有吹出现象,低估微粒中PAHs浓度值,影响其对人体健康风险评估的正确性.实验藉由自行设计滤纸吹出实验(Blow-off)装置,以7种PAHs同位素建立悬浮微粒中PAHs化合物吹出比值(Blow-off,θ),并解析... 详细信息

滤材截留粒状物中因采集气流常造成固相PAHs有吹出现象,低估微粒中PAHs浓度值,影响其对人体健康风险评估的正确性.实验藉由自行设计滤纸吹出实验(Blow-off)装置,以7种PAHs同位素建立悬浮微粒中PAHs化合物吹出比值(Blow-off,θ),并解析不同流速(20～60 cm/s)及温度(25～45℃)条件对固相PAHs吹出比值(θ)影响.实验结果显示少环PAHs化合物(如NaP,AcP)吹出比值明显较多环PAHs物质(如F1,Pyr)为大,随表面流速上升其吹出现象有增加趋势.少环PAHs化合物较易吹出但受温度影响较少(随温度上升θ增加仅约4%～17%);多环PAHs化合物吹出比值较低但随温度升高(25→45℃)吹出比值明显倍增(15%～34%增至32%～58%).

关键词：半挥发性有机化合物吹出现象采样误差风险评估室内空气清净技术

动物界的伪装高手们为了生存而练就的神奇技能

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环球人文地理 2021年第17期 72-79页

作者：石楠小札 james lee Holly Mandarich Pete Nuij Duncan Sanchez tobias dennisvdwater Emile Schilders Peter Boshra Mathew Schwartz David clode

自然界有许多神奇的动物,在潜伏着巨大危险的生活环境里,它们"挖掘"出了各自强大的伪装技能用以御敌,其方式花样百出,让人惊叹。在大自然中,动物们面临的危险与死亡,是直接而残酷的。物竞天择,适者生存。为了能够存活下去,它们演变出了...

自然界有许多神奇的动物,在潜伏着巨大危险的生活环境里,它们"挖掘"出了各自强大的伪装技能用以御敌,其方式花样百出,让人惊叹。在大自然中,动物们面临的危险与死亡,是直接而残酷的。物竞天择,适者生存。为了能够存活下去,它们演变出了一种超级技能——伪装。无害的毛毛虫会长出"蛇头",不择手段地欺骗天敌,只为成功羽化;海底变装大师乌贼能够变换肤色隐藏在周遭的角落,迷惑敌人、捕捉猎物;角蜥蜴、猪鼻蛇被逼入绝境,急中生智,直接装死,伺机逃出生天;地松鼠打入天敌响尾蛇的内部却不会被发现,堪比最优秀的"特工"……正是凭借各种瞒天过海的伪装技能,动物们才能在残酷的自然界活出属于自己的一片天地。

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裂纹稳定扩展的有限元分析

固体力学学报 1982年第4期 481-500页

作者：杜善义李德怡哈尔滨工业大学美国乔治·华盛顿大学

本文基于塑性理论的增量理论和等向硬化模型,用有限元法分析了具有中心裂纹的矩形板,在载荷逐渐增加的情况下,裂纹稳定扩展至失稳开裂的过程.用若干斜率不同的直线模拟材料的应力应变曲线.提供了数值分析的程序,证明了在裂纹稳定扩展中... 详细信息

本文基于塑性理论的增量理论和等向硬化模型,用有限元法分析了具有中心裂纹的矩形板,在载荷逐渐增加的情况下,裂纹稳定扩展至失稳开裂的过程.用若干斜率不同的直线模拟材料的应力应变曲线.提供了数值分析的程序,证明了在裂纹稳定扩展中,塑性能与裂纹尺寸成线性关系.并将数值分析结果与试验资料进行了比较.最后简单讨论了关于裂纹扩展的不同分析方法.

关键词：裂纹外加应力控制方程线性关系应变关系高倍缺陷(金属) 裂纹尺寸裂纹扩展有限元分析数值分析

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复合型断裂的非线性能量分析

固体力学学报 1983年第1期 23-39页

作者：沈为李德怡华中工学院乔治华盛顿大学

对于复合型断裂的线弹性分析,根据最大能量释放率判据,得到了一般的G-K关系,对于带有任意取向的裂纹并受双向加载的有限板的非线性能量释放率,本文给出了理论表达式,同时,本文用数值结果表示了非线性能量释放率的双向加载影响。

关键词：能量释放率双向加载判据裂纹扩展力复合型断裂初始裂纹线弹性分析双向载荷应力强度因子力学因子能量分析

Does the Archean Dongwanzi ophiolite complex exist?

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Does the Archean Dongwanzi ophiolite complex exist?

中国科学院地质与地球物理研究所2002学术年会

作者： Mingguo ZHAI~a Guochun ZHAO~b Qi ZHANG~a a.Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing,Chaoyang District,100029,China, b.Department of Earth Science,University of Hong Kong,james lee Science Building,Pokfulam Road, Hong Kong,China

Kusky et al(Science,2001,11 May,292) reported an ophioiite complex of late Archean age in the Dongwanzi area,North China *** found that some of their descriptions and interpretations on the Dongwanzi ophiolites are,although convincing,not consistent with the practical geological occurrences,and we think that the so-called"Archean Dongwanzi ophiolites"are questionable for the following reasons: 1) In Kusky’s report,the Dongwanzi ophioiite complex was considered to be composed of three NE-SW-trending parts,along which large amounts of pillow lavas and sheeted dykes were described to be *** fact,however,these three parts of the complex are a composite body of lithologies ranging in age from late Archean to Proterozoic or Mesozoic(Fig.1).They are separated by the Mesoproterozoic, unmetamorphosed,cover or juxtaposed by *** addition,we did not find any convincing pillows and sheeted dykes as described in the ***,we only found numerous highly sheared amphibolites and metagabbros in the south part and banded felsic gneisses in the north part. 2) In the report,the mafic-ultramafic accumulates in the Dongwanzi ophiolite complex are described as harzburgites,wehrlites,lherzolites,webbsterites and other peridotites interlayered with olivine-proxene ***,our field observation and thin-secction examination do not verify the existence of these rocks;they are only pyroxenes,hornblendites and *** rocks are characterized by high Fe and high REE and contain apatite-bearing V-Ti magnetites,which are now being mined by local ***,V-Ti magnetites are not associated with oceanic mantle rocks,which are normally characterized by high Mg and contain chromites. 3) At Dongwanzi village(Fig.3),they show gabbros intruded by six sheeted diabase dykes that are chilled predominantly on their northeast ***,our field observations combined with thin-section examinations show that the host rock in this locat

关键词： Where Archaean Dongwanzi Ophiolite

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清代缙绅录量化数据库与官员群体研究

清史研究 2016年第4期104卷 61-77页

作者：任玉雪陈必佳郝小雯康文林李中清上海交通大学历史系上海200240 香港科技大学人文社会科学学院社会科学部

本文主要介绍基于清代缙绅录构建大规模量化数据库的步骤和初步成果,并探讨利用历史大数据定量分析的方法研究清代官员群体的独特优势和潜力。清代缙绅录记载了中央及地方文武职官员的基本信息,每年四季出版。清代缙绅录量化数据库基于... 详细信息

本文主要介绍基于清代缙绅录构建大规模量化数据库的步骤和初步成果,并探讨利用历史大数据定量分析的方法研究清代官员群体的独特优势和潜力。清代缙绅录记载了中央及地方文武职官员的基本信息,每年四季出版。清代缙绅录量化数据库基于《清代缙绅录集成》的部分约有280万条记录,如果将研究组目前整理的海内外其他图书馆所藏缙绅录版本统计在内,总数据量或可达到500万条以上。目前清代缙绅录量化数据库构建初具雏形,可以支持系统的定量分析。更为重要的是,经验证,缙绅录量化数据库可与基于朱卷、题名录、同年齿录等其他相关史料构建的量化数据库进行匹配连接,具有成为研究清代官员群体及士人阶层最全面、系统、基础的核心量化数据库的巨大潜力。

关键词：清代缙绅录量化数据库官员群体

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秋收季节稻草燃烧粒子大气脱水醣类成分与粒径分布研究

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中国粉体技术 2009年第2期15卷 18-22页

作者：李经民陈宜慧白光宇蔡宜纹云林科技大学环境与安全卫生工程研究所台湾云林640 中央研究院环境变迁研究中心台湾台北115

以台湾中南部水稻作物区域为目标，探讨秋收稻草燃烧烟尘大气脱水醣类粒径分布成分特征；以改良离子层析仪解析3种大气悬浮粒子（PM2.5、PM10、总悬浮颗粒（TSP））大气脱水醣类成分浓度（左旋葡萄糖、甘露聚糖）与粒径分布，并探讨稻... 详细信息

以台湾中南部水稻作物区域为目标，探讨秋收稻草燃烧烟尘大气脱水醣类粒径分布成分特征；以改良离子层析仪解析3种大气悬浮粒子（PM2.5、PM10、总悬浮颗粒（TSP））大气脱水醣类成分浓度（左旋葡萄糖、甘露聚糖）与粒径分布，并探讨稻草燃烧对大气粒子的贡献率。结果显示，稻草燃烧期间大气（乡村，市郊）两种粒子（PM2.5与TSP）左旋葡萄糖浓度均大幅上升，两种粒子收成燃烧期间较非收成季节升高约5．5倍（较收成季节背景PM25与总悬浮颗粒分别高1．21倍与1．40倍）严重影响区域空气质量。市郊含左旋葡萄糖粒子分布以PM2.5细微粒为主（占TSP 81％以上）；乡村左旋葡萄糖粒径分布较广，PM2.5粒子占TSP56％左右，粗大粒子（PM〉10）占总悬浮颗粒的35％。此外，结果显示稻草生物质燃烧对区域PM2.5粒子平均贡献率为12％，市郊稍高于乡村（乡村、市郊平均贡献率分别为10．5％、13．0％），显现稻草生物质燃烧对台湾中南部空气质量有严重影响。

关键词：稻草燃烧脱水醣类大气悬浮颗粒

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Comparison of Pentax HiLine and Olympus Lucera systems at screening colonoscopy

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World Journal of Gastrointestinal Endoscopy 2013年第2期5卷 62-66页

作者： Alexey Chernolesskiy David Swain james C lee Gareth D Corbett Ewen AB Cameron Department of Gastroenterology Addenbrooke's HospitalCambridge CB2 0QQUnited Kingdom

AIM:To compare the performance characteristics of Pentax HiLine(PHL)(with i-scan) and Olympus Lucera(OL) systems in a screening ***:Screening colonoscopies in asymptomatic guaiac faecal occult blood test-positive patients with PHL(n = 58) and OL(n = 425) colonoscopes were *** procedures were performed by a single *** used white-light endoscopy(WLE) on scope insertion and contrast/surface enhancement(i-scan 1) on withdrawal,and OL utilised WLE both on insertion and *** age,sex,instrument insertion and withdrawal times,nurse assessed patient comfort scores,midazolam and fentanyl doses,procedure completion and rates of lesion detection were recorded separately for each *** between the groups were made using either Fisher's exact test(for dichotomous variables) or Mann-Whitney U test(for ordinal and continuous variables).RESULTS:Colonoscopy completion rates were similar in both groups:413/425(97.2%) for OL and 55/58(94.9%) for PHL(P = 0.24).For complete colonoscopies,the two groups were well matched for age,sex,colonoscope insertion times(mean 11.1 min in OL vs 11.6 min in PHL,P = 0.93) and normal colonoscopy withdrawal times(mean 15.6 min in OL vs 14.7 min in PHL,P = 0.2).Patients in the PHL group experienced a small increase in discomfort(mean patient comfort scores were 0.49 in the OL and 0.95 in the PHL group,P < 0.0001).While Fentanyl doses required were similar between groups(mean 57.5 μg in OL vs 61.4 μg in PHL,P = 0.13),slightly more Midazolam was required in the PHL group(mean 2.1 mg in OL vs 2.4 mg in PHL,P = 0.035).There was no difference in polyp(58% in OL vs 67% in PHL) or adenoma(49% in OL vs 56% in PHL) detection rates between the *** the total number of polyps and adenomas,nor the characteristics of these(including size,location or presence of advanced features) were different between the two ***:This study suggests that there is no advantage of either colonoscop

关键词： Pentax HiLine i-scan Polyp Adenoma Colonoscopy