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n. Symbol H
A colorless, highly flammable element, that occurs as a diatomic molecule, H2, the lightest of all gases and the most abundant element in the universe, used in the production of synthetic ammonia and methanol, in petroleum refining, in the hydrogenation of organic materials, as a reducing atmosphere, in oxyhydrogen torches, in cryogenic research, and in rocket fuels. Atomic number 1; atomic weight 1.00794; melting point -259.1°C; boiling point -252.8°C; density at 0°C 0.08988 gram per liter; valence 1. See Periodic Table.

[French hydrogène : Greek hudro-, hydro- + French -gène, -gen.]

hy·drog′e·nous (-drōj′ə-nəs) adj.


(Chemistry) of or containing hydrogen


(haɪˈdrɒdʒ ə nəs)

of or containing hydrogen.
References in periodicals archive ?
Transform is to transform the extracted data according to the previously designed rules and process redundant and ambiguous data so that originally hydrogenous data format can be unified.
Thermal neutron imaging is ideal to examine highly hydrogenous materials--such as polymers, fuel cells and biological systems--and provides an excellent complement to x-ray imaging, which preferentially highlights high-Z features.
Rare earth, major and trace elements in Jurassic manganese shales of the Northern Calcaeous Alps: hydrothermal versus hydrogenous origin of stratiform manganese deposits.
Among the topics are modeling approaches to heat and mass transfers in porous wicks, mechanisms of intensive heat transfer for different modes of boiling, practical applications of heat pipes and opportunities for innovative applications because of global warming, sorption systems with heat pipe thermal management for storing and transporting hydrogenous gas, and fluid flow and heat transfer with phase change in minichannels and microchannels.
Various discrimination diagrams as proposed by several workers in order to distinguish manganese ores of various origins have been used to understand the hydrothermal or hydrogenous input during the formation of these Mn-ores.