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811.
Barbara J. Thompson Sarah E. Gibson Peter C. Schroeder David F. Webb Charles N. Arge Mario M. Bisi Giuliana de Toma Barbara A. Emery Antoinette B. Galvin Deborah A. Haber Bernard V. Jackson Elizabeth A. Jensen Robert J. Leamon Jiuhou Lei Periasamy K. Manoharan M. Leila Mays Patrick S. McIntosh Gordon J. D. Petrie Simon P. Plunkett Liying Qian Peter Riley Steven T. Suess Munetoshi Tokumaru Brian T. Welsch Thomas N. Woods 《Solar physics》2011,274(1-2):29-56
We present an overview of the data and models collected for the Whole Heliosphere Interval, an international campaign to study the three-dimensional solar?Cheliospheric?Cplanetary connected system near solar minimum. The data and models correspond to solar Carrington Rotation 2068 (20 March??C?16 April 2008) extending from below the solar photosphere, through interplanetary space, and down to Earth??s mesosphere. Nearly 200 people participated in aspects of WHI studies, analyzing and interpreting data from nearly 100 instruments and models in order to elucidate the physics of fundamental heliophysical processes. The solar and inner heliospheric data showed structure consistent with the declining phase of the solar cycle. A closely spaced cluster of low-latitude active regions was responsible for an increased level of magnetic activity, while a highly warped current sheet dominated heliospheric structure. The geospace data revealed an unusually high level of activity, driven primarily by the periodic impingement of high-speed streams. The WHI studies traced the solar activity and structure into the heliosphere and geospace, and provided new insight into the nature of the interconnected heliophysical system near solar minimum. 相似文献
812.
A possible suture between an old craton in West Africa and the Arabian—Nubian shield is marked by a persistent zone of Phanerozoic weakness. This zone extends between the Nile and Niger deltas and passes through the Qattara embayment, along the Bahariya fault, through the Kufra basin, between the Tibesti and Jabal al Uwaynat massifs, through the Bahr el Ghazal and Lake Chad areas, and along the Benoue trough. 相似文献
813.
A. Baran R. Oreiro A. Pigulski F. Pérez Hernández A. Ulla M. D. Reed C. Rodríguez-López P. Moskalik S.-L. Kim W.-P. Chen R. Crowe M. Siwak L. Armendarez P. M. Binder K.-J. Choo A. Dye J. R. Eggen R. Garrido J. M. González Pérez S. L. Harms F.-Y. Huang D. Kozie H.-T. Lee J. MacDonald L. Fox Machado T. Monserrat J. Stevick S. Stewart D. Terry A.-Y. Zhou S. Zoa 《Monthly notices of the Royal Astronomical Society》2009,392(3):1092-1105
814.
This paper analyzed forest land use change in Trans-Boundary Laos–China Biodiversity Conservation Area which is called Namha National Biodiversity Conservation Areas (Namha NBCAs), with 1992 and 2002 TM (ETM). Based on GIS and statistical methods, the intensity, state index of land use change and transfer matrix were used to study spatio- temporal land use change in the region. The results showed that the area of forest land decreased greatly, also the area of bamboo and grassland decreased. The other way round, the area of unstocked forest, slash and burn and rice paddy land increased. As a whole, the intensity of forest land change was higher, but others were lower. From the transfer matrix, most of the forest land changed into unstocked forest and urban area, some to slash and burn. The grassland and bamboo were mainly transferred to forest and unstocked forest. The unstocked forest land mostly came from forest land and grassland. It was showed there were three main causes of the land use change namely: opium poppy cultivation, rubber plantation and also ecotourism activities and finally some policies were developed in order to address the land use change in the study areas. 相似文献
815.
816.
New results of the numerical modeling of the response of the outer atmosphere of the Sun to an impulsive heating are presented.
Features of the general process are considered both for powerful and weak solar flares. For the most powerful flares it is
necessary to take into account the effect of a saturation of the heat flow. Though for the most powerful solar flares the
saturation of a thermal flow is not such large, the influence of this effect is important for cases of powerful flares on
red dwarf stars, strongly limiting the input of the thermal energy downwards. The response of the atmosphere, which consists
of the chromosphere, the transition region and the corona, to weak heating is characterized by creation no one as usually
but two ascending coronal flows. The occurrence of the additional flow at coronal heights is caused by the inhomogeneous initial
heating of the outer atmosphere. Some types of soft X-ray and UV-jets can be associated with such additional flow.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
817.
E. C. Hopewell M. J. Barlow J. E. Drew Y. C. Unruh Q. A. Parker M. J. Pierce P. A. Crowther C. Knigge S. Phillipps A. A. Zijlstra 《Monthly notices of the Royal Astronomical Society》2005,363(3):857-866
We report the discovery of five massive Wolf–Rayet (WR) stars resulting from a programme of follow-up spectroscopy of candidate emission-line stars in the Anglo-Australian Observatory United Kingdom Schmidt Telescope (AAO/UKST) Southern Galactic Plane Hα survey. The 6195–6775 Å spectra of the stars are presented and discussed. A WC9 class is assigned to all five stars through comparison of their spectra with those of known late-type WC stars, bringing the known total number of Galactic WC9 stars to 44. Whilst three of the five WC9 stars exhibit near-infrared (NIR) excesses characteristic of hot dust emission (as seen in the great majority of known WC9 stars), we find that two of the stars show no discernible evidence of such excesses. This increases the number of known WC9 stars without NIR excesses to seven. Reddenings and distances for all five stars are estimated. 相似文献
818.
819.
820.
A. M. Dolgonosov N. K. Kolotilina A. G. Prudkovskii 《Geochemistry International》2016,54(13):1236-1251
This paper briefly describes original developments in the theoretical and practical ion chromatography. It is demonstrated that new methods may be applied for the highly-selective analysis of complex natural objects. The determination of different species of sulfur and other ions in the condensates of fumarolic gases is considered in detail as an example. 相似文献