منابع مشابه
Molecular Hydrogen formation on grain surfaces
We reconsider H2 formation on grain surfaces. We develop a rate equation model which takes into account the presence of both physisorbed and chemisorbed sites on the surface, including quantum mechanical tunnelling and thermal diffusion. In this study, we took into consideration the uncertainties on the characteristics of graphitic surfaces. We calculate the H2 formation efficiency with the Lan...
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Because H2 formation on dust grain surfaces completely dominates gas-phase H2 formation in local molecular clouds, it is often assumed that gas-phase formation is never important. In fact, it is the dominant mechanism in a number of cases. In this paper, I briefly summarize the chemistry of gas-phase H2 formation, and show that it dominates for dust-to-gas ratios less than a critical value Dcr....
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The formation of molecular hydrogen in the interstellar medium takes place on the surfaces of dust grains. Hydrogen molecules play a role in gasphase reactions that produce other molecules, some of which serve as coolants during gravitational collapse and star formation. Thus, the evaluation of the production rate of hydrogen molecules and its dependence on the physical conditions in the cloud ...
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In this article we consider surfaces in the product space H 2 × R of the hyperbolic plane H with the real line. The main results are: a description of some geometric properties of minimal graphs; new examples of complete minimal graphs; the classification of umbilical surfaces.
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In this study, a strain of lactic acid bacteria Streptococcus salivarius was studied for its capacity to remove hexavalent chromium (Cr (VI)) from a liquid medium and to form biofilm. Both properties are useful for using the strain in bioremediation of metal-contaminated effluents. For biofilm formation capacity, three methods were used: the tube method (TM), the Congo red agar method (CRA) and...
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ژورنال
عنوان ژورنال: Proceedings of the International Astronomical Union
سال: 2006
ISSN: 1743-9213,1743-9221
DOI: 10.1017/s1743921306007344