Molecular gas and star formation in the SAURON early-type galaxies     

Francoise Combes  Lisa M. Young  Martin Bureau 《Monthly notices of the Royal Astronomical Society》2007,377(4):1795-1807

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Photo's from Proceedings of the Third MicroQuasar Workshop; Granada Worshop on Galactic Relativistic Jet Sources – Granada,Spain, 11–13 September 2000     

Francoise Combes 《Astrophysics and Space Science》2001,277(1):29-38

Knowledge of the molecular component of the ISM is fundamental to understand star formation. The H₂ component appears to dominate the gas mass in the inner parts of galaxies, while the HI component dominates in the outer parts. Observation of the CO and other lines in normal and starburst galaxies have questioned the CO-to-H₂ conversion factor, and detection of CO in dwarfs have shown how sensitive the conversion factor is to metallicity. Our knowledge has made great progress in recent years, because of sensitivity and spatial resolution improvements. Large-scale CO maps of nearby galaxies are now available, which extend our knowledge on global properties, radial gradients, and spiral structure of the molecular ISM. Millimetric interferometers reveal high velocity gradients in galaxy nuclei, and formation of embedded structures, like bars within bars. Galaxy interactions are very effective to enhance gas concentrations and trigger starbursts. Nuclear disks or rings are frequently observed, that concentrate the star formation activity. Since the density of starbursting galaxies is strongly increasing with redshift, the CO lines and the mm dust emission are a privileged tool to follow evolution of galaxies and observe the ISM dynamics at high redshift: they could give an answer about the debated question of the star-formation history, since many massive remote starbursts could be dust-enshrouded.  相似文献   

中国城市间技术转移的空间特征与邻近性机理   总被引：7，自引：2，他引：5  

张翼鸥  谷人旭  马双 《地理科学进展》2019,38(3):370-382

技术转移是区域经济发展的主要方式。城市作为多种要素流动的中心,彼此间的相互作用和联系状况,是城市地理研究的重要内容。因此,在知识经济时代,对技术转移的机理进行探讨尤为重要。在此背景下,论文基于国家知识产权局2000—2015年的专利转移数据,借助Gephi、ArcGIS和Stata等工具,对中国技术转移网络的主体结构、分部类模式及其空间特征进行了探究。结果表明：① 就技术转移网络的主体而言,虽然民营企业和高校的地位不断攀升,但多数联系建立在高校、科研院所与其衍生企业之间,说明网络整体连通性较低,溢出效应微弱;② 从分部类专利转移数据来看,对创新能力要求较高的知识往往在相对较少的地方产生,且其转移的空间尺度主要集中于城市内,说明中国城市间技术转移存在一定的地域阻隔;③ 对多维邻近性及其影响的回归分析表明,多数城市在建立创新联系时,更倾向与同一行政区内或地理、技术规模邻近的城市进行专利转移,即地理邻近、技术邻近、社会邻近对中国产学研合作网络的构架具有正向的促进作用。  相似文献   

Taille et age au debut de la metamorphose chez la sole (Solea solea (L.)) du golfe de Gascogne     

Amara  Rachid; Lagardere  Francoise 《ICES Journal of Marine Science》1995,52(2):247-256

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Book review     

Francoise Praderie 《Solar physics》1979,62(1):221-221

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Orbital resonances and Poynting-Robertson drag confining dust particles in β-Pic disk     

Daniela Lazzaro  Bruno Sicardy  Francoise Roques  Hans Scholl 《Celestial Mechanics and Dynamical Astronomy》1993,56(1-2):395-396

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Three-dimensional finite element modelling of stress relaxation tests in anisotropic clayey medium: direct problem and back analysis     

Richard Giot  Albert Giraud  Francoise Homand 《Geotechnical and Geological Engineering》2006,24(4):919-947

This paper deals with a new strategy for initial stress identification by stress relaxation methods, coupled with finite element calculation, and applied to the overcoring test. The back-analysis of such a test uses an inversion method which consists in the minimisation, with a gradient-based algorithm, of a cost functional of least-squares type, which quantizes the difference between measured and computed strains. The computed strains are assessed by three-dimensional finite element modellings of the overcoring test. The inversion methodology is applied to a recent in situ overcoring test performed at Mont Terri laboratory, Switzerland. The inversion gave good results and allows us to validate the inversion methodology. The constitutive law considered for this application is transverse isotropic elasticity but the inversion method developed is applicable to most constitutive laws and every kind of in situ test.  相似文献