Results 41 to 50 of about 470 (131)
Photoionization and photodissociation in diffuse interstellar clouds
The Astrophysical Journal, 1981 An accurate treatment of radiative transfer is used to explore the effects of grain scattering properties on the photoionization and photodissociation efficiencies of atomic and molecular constituents in diffuse clouds and to calculate the rates of heat deposition by photoelectric emission from grains.
W. G. Roberge +2 more
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Entropy Export and Chemical Reactions in Plasmas
Plasma Processes and Polymers, Volume 23, Issue 1, January 2026.In a non‐equilibrium plasma, energy is transferred to molecules by electron‐impact (1), collisions among excited molecules (2), and Joule heating (3). The entropy balance for this open system relates the energy available per molecule to changes in entropy, which determines plasma‐based gas conversion. ABSTRACT Is plasma truly a “fourth state of matter”?
Dirk Hegemann, Ramses Snoeckx
wiley +1 more source
Adsorption of Helium on Cationic or Anionic Tetracene and Pentacene
Small Structures, Volume 7, Issue 1, January 2026.How does the arrangement of helium atoms that are adsorbed on tetracene or pentacene ions change with increasing coverage? When does the adsorption layer change from 1D to 2D, and to 3D? Is the transition abrupt? Are the helium atoms localized? Is the arrangement the same for cations and anions? What changes as the acene grows in length?
Miriam Kappe +6 more
wiley +1 more source
Interstellar Migration, the Population ‘Problem’ and the Climate Emergency
Critical Quarterly, Volume 68, Issue 1, Page 103-119, April 2026.
Anna Hartnell
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Kinetics and Thermodynamics of Tautomerization Reactions of 1,1‐ and 1,2‐Ethenediols
International Journal of Chemical Kinetics, Volume 57, Issue 12, Page 687-696, December 2025.ABSTRACT Tautomerism is a common phenomenon amongst organic molecules with easily interconvertible isomers, which can impact drug action and toxicity. Here we are interested in the enols of carboxylic acids, which are known to be much less stable than their acid counterparts.
Judith Würmel, John M. Simmie
wiley +1 more source
Plasma Production by Laser Ablation of Heavy Metals
Contributions to Plasma Physics, Volume 65, Issue 7, August 2025.ABSTRACT An Nd:YAG focused laser operating at 1064 nm, 3 ns pulse width, 360 mJ pulse energy, is employed to irradiate heavy metals, such as Ta, W, Pt, Au, and Pb. The in‐vacuum irradiation produces an expanding plasma at the target surface which has high density, temperature, and kinetic energy of emitted ions. Ions have a velocity of the order of 104
L. Torrisi, M. Cutroneo, A. Torrisi
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Diffuse interstellar medium and the formation of molecular clouds [PDF]
, 2009 (Abridged) The formation of molecular clouds (MCs) from the diffuse interstellar gas appears to be a necessary step for star formation, as young stars invariably occur within them. However, the mechanisms controlling the formation of MCs remain controversial.
Hennebelle, P. +2 more
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Interstellar shocks and molecular CH/+/ in diffuse clouds
The Astrophysical Journal, 1980 The influence of shocks on the abundances of molecules in diffuse interstellar clouds is investigated with special emphasis on molecular CH/sup +/. Idealized shocks with plausible parameters are found to produce column densities for CH/sup +/ in the hot, postshock gas which are comparable with measured values in interstellar clouds (up to about 10/sup ...
M. Elitzur, W. D. Watson
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Enigma of H 3 + in Diffuse Interstellar Clouds [PDF]
, 2003 H 3 + is of fundamental importance to interstellar chemistry both because it is a hydrogenic species (and >9O% of all nuclei in the universe are hydrogen nuclei; see Fig. 1) and because it serves as the universal protonator, initiating a chain of ion-neutral reactions that is responsible for the formation of most interstellar molecules.
Benjamin J. McCall, Takeshi Oka
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The carbon abundance in diffuse interstellar clouds
The Astrophysical Journal, 1981 When N/sub H2/roughly-equal1-40 x 10/sup 19/ cm/sup -2/ in a given direction, or f equivalent 2N/sub H2//N/sub H/>10/sup -1.4/, the column densities of C I and H/sub 2/ are strongly correlated even though N/sub C/ /sub i/ and N/sub H/ are not. All or most of the observed C I in such directions is harbored by a single, predominantly molecular (H/sub 2/>>
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