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941.
Comparison of natural marine (nodular and granular) carbonate-apatites and pathogenic mineral structures formed in human cardiac valves by methods of scanning electron and high-resolution transmission microscopy revealed common morphological features corresponding to the bacterial origin of calcium phosphates. These features may be considered typomorphic ones regardless of their formation environments (in vivo or in nature). 相似文献
942.
Yu. M. Pushcharovsky 《Geotectonics》2012,46(2):111-121
Typification of tectonic structures is one of the important lines of tectonic research. Recently, I have published several articles, which are concerned with deepwater oceanic basins. This paper is focused on tectonic typification of deepwater basins of the North Atlantic. They are attributed to three types: perispreading, central thalassogenic, and pericontinental. The first type comprises the Irminger, Iceland, Greenland, and Lofoten basins. The first two basins are associated with the Reykjanes Ridge and the two others, with the Mohns Ridge. The central thalassogenic type is exemplified in the Norwegian Basin, while the pericontinental type in the Rockall Trough. Two systems of basins are distinguished by morphostructural and historical-geological features: the northern system of the Oligocene-Quaternary structures and the southern system of the Paleocene-Quaternary structures. The Greenland-Faroe tectonovolcanic zone serves as their tectonic interface. In the tectonic typology of their deepwater basins, the North Atlantic is closer to the Indian than to other oceans. The present-day configuration of the northern basins is determined by neotectonics. The tectonic movements in the northern system of basins at this stage were more contrasting than in the southern system. This explains the greater depth of the former basins. The spatial position of the deepwater basins belonging to different types determines the tectonic segmentation of the oceanic bottom. The southern, central, and northern latitudinal segments correspond to different geodynamic states of the Earth’s interior. 相似文献
943.
采用投入产出分析法,对长江经济带七省二市2007年物流产业的前后向关联度及对国民经济的波及效应进行研究,发现长江经济带物流产业中间投入率总体保持上升趋势,而中间需求率则随着区域工业化程度呈现先上升后下降的变化。长江经济带物流产业结构特征呈现明显的差异,上海、安徽的物流产业机械化程度最高,安徽、湖北的物流产业具有较典型的劳动密集型特征,上海物流产业的产业结构高级化特征最为明显,物流企业之间的合作衔接也最为紧密。长江下游各省市的物流产业发展具有明显的出口依赖特征,重庆和四川具有明显的资本形成依赖特征,而江西、湖南和四川等人口大省则具有较明显的消费依赖特征。 相似文献
944.
以经济活动为主要依据,结合人群文化和环境生态特质,概括了我国山区人地系统基本结构类型.通过对人地系统结构变化的动力及作用机制分析,预测我国山区人地系统的主要变化趋势.从持续发展角度,提出了我国山区人地系统结构优化的特殊性及要点. 相似文献
945.
Profiles observed by Sea-Wing underwater gliders are widely applied in scientific research. However, the quality control(QC) of these data has received little attention. The mismatch between the temperature probe and conductivity cell response times generates erroneous salinities, especially across a strong thermocline. A sensor drift may occur owing to biofouling and biocide leakage into the conductivity cell when a glider has operated for several months. It is therefore critical to design a mature real-time QC procedure and develop a toolbox for the QC of Sea-Wing glider data. On the basis of temperature and salinity profiles observed by several Sea-Wing gliders each installed with a Sea-Bird Glider Payload CTD sensor, a real-time QC method including a thermal lag correction, Argo-equivalent real-time QC tests, and a simple post-processing procedure is proposed. The method can also be adopted for Petrel gliders. 相似文献
946.
947.
大洋富钴结壳的基本框架——超微生物建构的锰质叠层石柱体 总被引:1,自引:0,他引:1
大洋富钴结壳和锰结核一样是潜在的海底矿产资源,对其成因的研究将有助于指导找矿和资源评价。通过大型反光显微镜、透射电子显微镜和其他测试手段,系统研究了结壳的结构构造、物质组成以及叠层石纹层与超微生物的关系。发现结壳与光滑型锰结核的叠层石类型及超微生物种极其相似,它们都以微小叠层石和中华微放线菌为主要特征,具有相同的生物成因机制。认为超微生物建构的锰质叠层石柱体是大洋富钴结壳的基本框架,从而对结壳矿体的形成提出了新的见解。 相似文献
948.
海洋综合管理的实施要求公众参与,这是海洋事业发展和公众实现自身利益的现实需要.本文在对公众参与的内涵、我国公众参与的现状及问题进行分析的基础上,从制度化建设、思想观念转变和信息公开化三个方面提出了解决问题的对策. 相似文献
949.
Motivated by currently available direct observations of occulting tori in Seyfert galaxies and ongoing discussions about tori as important structural components in Active Galactic Nuclei, we discuss the possibility that the “spinning up” of a torus by radiation or winds could transform it into a dipolar toroidal vortex. The vortex motion balances the torus’ self-gravitation, and can explain the existence of cool, thick tori inferred from observations. In turn, the toroidal vortex can be a source of matter to feed the accretion disk. The resulting instability could result in flares accompanied by the ejection of matter. Our numerical estimates of the model parameters for luminosities close to the Eddington limit are consistent with the observational data. 相似文献
950.
A model red giant with a mass of 5 M⊙ a luminosity of 41,740 L⊙, and a radius of 960 R⊙ and with a strange quark star as its core is constructed, and it is compared with a Thorne-Zytkow object having similar integrated
parameters. The difference in internal structure is manifested right at the dense core: matter above the core is held off
only by γ rays from the strange star, and convection is maintained down to the strange star. The lifetime of a red giant containing
a strange star turns out to be almost 500 times shorter than that of a Thorne-Zytkow object — on the order of 105 years.
Translated from Astrofizika, Vol. 41. No. 4, pp. 533–544, October–December, 1998. 相似文献