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Radio observations of some active regions (ARs) obtained with the Nobeyama radioheliograph at λ=1.76cm are used for estimating the magnetic field strength in the upper chromosphere, based on thermal bremsstrahlung. The results are compared with the magnetic field strength in the photosphere from observations with the Solar Magnetic Field Telescope (SMFT) at Huairou Solar Observing Station of Beijing Astronomical Observatory. The difference in the magnetic field strength between the two layers seems reasonable. The solar radio maps of active regions obtained with the Nobeyama radioheliograph, both in total intensity (I-map) and in circular polarizations (V-map), are compared with the optical magnetograms obtained with the SMFT. The comparison between the radio map in circular polarization and the longitudinal photospheric magnetogram of a plage region suggest that the radio map in circular polarization is a kind of magnetogram of the upper chromosphere. The comparison of the radio map in total intensity with the photospheric vector magnetogram of an AR shows that the radio map in total intensity gives indications of magnetic loops in the corona, thus we have a method of defining the coronal magnetic structure from the radio I-maps at λ=1.76 cm. Analysing the I-maps, we identified three components: (a) a compact bright source; (b) a narrow elongated structure connecting two main magnetic islands of opposite polarities (observed in both the optical and radio magnetograms); (c) a wide, diffuse, weak component that corresponds to a wide structure in the solar active region which shows in most cases an S or a reversed S contour, which is probably due to the differential rotation of the Sun. The last two components suggest coronal loops on different spatial scales above the neutral line of the longitudinal photospheric magnetic field.  相似文献   
4.
Future trends in urbanization in the USSR east of the Urals are considered using official Soviet data from 1959 to 1985. "Absolute and relative growth and growth rates are calculated for economic regions, oblast-level administrative entities, and individual cities, as well as for city-size categories. The nature of Siberian growth suggests that in addition to serving as centers of resource exploitation, Siberian cities also function as growth poles for more integrated development. The analysis serves as the preliminary stage for proposed future research on the extent of Siberian urban development and the integration of Siberia into the Soviet economy."  相似文献   
5.
Bahr J  Mertins G 《Erdkunde》1985,39(3):218-238
"An attempt is made in the light of an analysis of population changes occurring in several sub-districts of Greater Santiago in the period between the last population censuses of 1970 and 1982, based on small-area census units (distritos and communas) to draw attention to the effects on the spatial growth of the city resulting from changed conditions in the political and juridical sphere since the change of power in 1973." The effect of changes in government policy concerning the liberalization of the property market and the illegal occupation of land are noted. (summary in ENG)  相似文献   
6.
The time evolution of a two-dimensional line thermal-a turbulent flow produced by an initial element with signifi-cant buoyancy released in a large water body, is numerically studied with the two-equation k - e model for turbulence closure. The numerical results show that the thermal is characterized by a vortex pair flow and a kidney shaped concentra-tion structure with double peak maxima; the computed flow details and scalar mixing characteristics can be described by self-similar relations beyond a dimensionless time around 10. There are two regions in the flow field of a line thermal: a mixing region where the concentration of tracer fluid is high and the flow is turbulent and rotational with a pair of vortex eyes, and an ambient region where the concentration is zero and the flow is potential and well-described by a model of doublet with strength very close to those given by early experimental and analytical studies. The added virtual mass coeffi-cient of the thermal motion is found to be approximat  相似文献   
7.
蒋加伦  徐芝敏 《海洋学报》1983,5(6):783-788
1980年我国初探南极,进行科学考察.采到了几种藻类及腔肠动物类标本,在这些生物体表上,发现着生许多硅藻,这些附着硅藻类的形态结构、个体大小都有差异.尤其卵形藻类、楔形藻类数量最多,种类变化也复杂,我们对样品进行分离、筛选获得了大量珍贵的附着硅藻标本,并对这些标本做细致观察,个别种类还经电子显微镜作超微结构的拍照与分析.  相似文献   
8.
热带洋面上最小OLR轴与最大SST轴关系的气候学研究   总被引:3,自引:0,他引:3  
蒋尚城  郭炜 《海洋学报》1992,14(1):124-128
热带洋面上的SST(海表面温度)是影响大气环流变化及气候异常的重要参数.众所周知的埃尔尼诺事件即是首先从南美海岸的SST异常增温发现的.自有卫星观测以来,OLR(射出长波辐射)亦已成为反映热带洋面上的大气凝结热源、降水量及对流活动等重要现象的参数,而得到了戛来越多的气象学家的重视和广泛的应用[1].事实上,在热带洋面上OLR所反映的云是海气相互作用的产物.海洋对大气的相互作用首先是通过SST的变化来影响大气的.海洋上的大气受热对流产生的云(反映为低OLR)反过来又会阻挡太阳辐射而影响SST.  相似文献   
9.
Bacteria abundance, chlorophyll a, ATP and POC concentrations and respiration rates of microorganisms in the Changjiang Estuary and the plume were determined in July 1986. The high values of bacteria abundance occurred in the river mouth in association with suspended matter. It is assumed that bacteria were the major contributor to ATP and the main consumer of dissolved oxygen, and that the relationship between ATP and POC was present in that area. In the dilution zone (salinity; 25-30), instead of bacteria, phytoplankton was the major contributor to ATP and respiration rates, due to diatom bloom. Close relationships between Chi a and ATP, and ATP and POC were observed. Contribution of microbial carbon to POC was also estimated.  相似文献   
10.
G.  M.  Ingram  T.  J.  Chisholm  C.  J.  Grant  万玲 《海洋地质》2006,(2):71-80
在西北婆罗州深水区,一个活动的海上褶皱冲断带内拥有大量已经证实的烃类聚集,相信继续的勘探活动还会发现相当可观的油气。在新近纪大规模褶皱冲断带中发现典型的圈闭几何形态是上盘背斜、前陆褶皱及隆起和逆断层下盘错动断开处。商业性钻井目标位于变形的中新统和上新统沉积地层中,其中充满的油气来自现今仍然活跃的含油气系统。此处主要面临的问题是避免钻探活动变形和近期隆起期间烃类已经排出的圈闭。构造变形阶段研究列出了控制圈闭形成史和烃类保存史的一些关键要素。本文目的是提供一个有关西北婆罗州深水区褶皱冲断带的总体看法,为今后这一地区的油气勘探介绍一些重要结果。  相似文献   
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