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In the past several years growing emphasis on the environment has generated a minor revolution in the field of air quality instrumentation. New instruments have been appearing steadily and will no doubt continue to do so in the near future. While this new generation of instrumentation is being field tested, refined, and applied to air quality measurement problems, development of more sensitive and versatile techniques continues. This paper gives an overview of the new generation of air quality monitoring instruments, comparing them with some more traditional methods. 相似文献
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Michael Loewenstein David S. Davis 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(12):1972-1974
We discuss the elemental composition in the hot ISM of elliptical galaxies derived from new and recent X-ray spectral analysis in the context of new phenomenological models of their chemical evolution. Star formation histories, the IMF, the astrophysics of supernovae, and the nature of galactic winds impact the metal content and relative abundances in the hot ISM. We evaluate how X-ray spectroscopy may be utilized to deconstruct how elliptical galaxies, and the stellar populations that compose them, form and evolve, with an emphasis on present and future high resolution spectroscopic analysis. 相似文献
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