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991.
The Texas Gulf Coast (TGC) contains the greatest number of favorably co-located CO2 sources and sinks in Texas that favor new potential clean-coal facilities. Areas in the TGC with clean-coal potential were delineated by mapping spatial linkages between coal- and lignite-bearing formations and geologic and infrastructure factors that include proximity to existing fields from mine-mouth power plants for enhanced oil recovery (EOR), length of new pipelines to transport CO2 from new clean-coal facilities to either EOR fields or to brine formations for deep storage, proximity to centers of electric load, and depth to subsurface coal for enhanced coalbed methane recovery. Other factors include thickness of brine formations for deep storage of CO2, groundwater and surface-water availability, and proximity to railroads for haulage of western U.S. coal feedstock. Geospatial analysis of maps portraying the distribution of these factors, together with data on volumes of oil recoverable from miscible CO2 flooding of oil fields, indicates that optimal areas for new clean-coal sites in the TGC are in east and southeast Texas. CO2 pipeline networks linking these sites to EOR fields are integral components of systems that can typically recover 5–50 million stock tank barrels from miscible CO2 flooding from each EOR field. Many of these fields with EOR potential (for example, Neches, Long Lake, Conroe, and Livingston) have a great potential for stacked CO2 storage, in which multiple reservoir zones can undergo EOR development and deeper zones in the field can accommodate excess CO2 from EOR operations. 相似文献
992.
A new species of sphaeronectid calycophoran siphonophore, Sphaeronectes pughi sp. nov. is described from material collected in the subantarctic zone, south of Australia. An identification key for sphaeronectid nectophores is provided, with illustrations of the eleven recognized species. 相似文献
993.
A very large surface inversion, which would not have been detected at the official recording height of 2 m above the mire surface, was recorded at the snow surface of an earth hummock in Lapland. The maximum inversion was 35 °C, and the monthly temperature departure was 7.8 °C in December 1992. The characteristics of the surface inversion are compared with conditions during another winter when no long inversion periods occurred. The presence of this surface inversion may explain the formation of new permafrost in pounus, even when official records showed no unusually low temperatures. 相似文献
994.
Ana I. Gómez de Castro 《Astrophysics and Space Science》2009,320(1-3):97-106
Planetary systems are angular momentum reservoirs generated during star formation. This accretion process produces very powerful engines able to drive the optical jets and the molecular outflows. A fraction of the engine energy is released into heating thus the temperature of the engine ranges from the 3000 K of the inner disk material to the 10 MK in the areas where magnetic reconnection occurs. There are important unsolved problems concerning the nature of the engine, its evolution and the impact of the engine in the chemical evolution of the inner disk. Of special relevance is the understanding of the shear layer between the stellar photosphere and the disk; this layer controls a significant fraction of the magnetic field building up and the subsequent dissipative processes ougth to be studied in the UV. This contribution focus on describing the connections between 1 Myr old suns and the Sun and the requirements for new UV instrumentation to address their evolution during this period. Two types of observations are shown to be needed: monitoring programmes and high resolution imaging down to, at least, milliarsecond scales. 相似文献
995.
Rodolfo H. Barbá Jesús Maíz Apellániz Enrique Pérez Mónica Rubio Alberto Bolatto Cecilia Fariña Guillermo Bosch Nolan R. Walborn 《Astrophysics and Space Science》2009,324(2-4):309-313
We present the first high-spatial-resolution near-infrared (NIR) imaging of NGC604, obtained with the NICMOS camera onboard the Hubble Space Telescope (HST). These NICMOS broad-band images reveal new NIR point sources, clusters, and diffuse structures. We find an excellent spatial correlation between the 8.4 GHz radio continuum and the 2.2 μm nebular emission. Moreover, massive young stellar object candidates appear aligned with these radio peaks, reinforcing the idea that those areas are star-forming regions. Three different scaled OB associations are recognized in the NICMOS images. The brightest NIR sources in our images have properties that suggest that they are red supergiant stars, of which one was previously known. This preliminary analysis of the NICMOS images shows the complexity of the stellar content of the NGC604 nebula. 相似文献
996.
Boris Shustov Mikhail Sachkov Ana I. Gómez de Castro Maohai Huang Klaus Werner Norbert Kappelmann Isabella Pagano 《Astrophysics and Space Science》2009,320(1-3):187-190
The World Space Observatory UltraViolet (WSO–UV) is an international space mission devoted to UV spectroscopy and imaging. The observatory includes a 170 cm aperture telescope capable of high-resolution and long slit low-resolution spectroscopy, and deep UV and optical imaging. The observatory is designed for observations in the ultraviolet domain where most of astrophysical processes can be efficiently studied with unprecedented capability. 相似文献
997.
BD+53°2790, an O9.5V star, is the optical counterpart to the HMXRB 4U 2206+54. This system was classified initially as a BeX, but observational evidence soon stressed the need to revise this classification. The permanent asymmetry in the Hα line profiles (in contrast with the cyclic variations shown by Be stars), the variations in the profile of this line in time scales of hours (while time scales from weeks to months are expected in Be stars), and the lack of correlation between IR observables and Hα line parameters, strongly suggest that, while BD+53°2790 contains a circumstellar disc, it is not like the one present in Be stars (Blay et al. 2006). Furthermore, there is evidence of overabundance of He in BD+53°2790. Together with the presence of an anomalous wind, found through UV spectroscopy, the possibility to link this star with the group of He rich stars is open. We will discuss the work done with IUE data from BD+53°2790 and the unexpected finding of a slow and dense wind, very rare for an O9.5V star. 相似文献
998.
999.
Solar Physics - Elemental composition and energy spectra of ~?0.1?–?1.0 MeV/n heavy ions were analyzed in two corotating interaction region (CIR) events... 相似文献
1000.
We introduce and describe our newly developed code that simulates light curves and radial velocity curves for arbitrary transiting exoplanets and its satellite. The most important feature of the program is the calculation of radial velocity curves and the Rossiter–McLaughlin effect in such systems. We discuss the possibilities for detecting the exomoons taking the abilities of Extremely Large Telescopes into account. We show that satellites may be detected also by their RM effect in the future, probably using less accurate measurements than promised by the current instrumental developments. Thus, RM effect will be an important observational tool in the exploration of exomoons. 相似文献