GB/T 24499-2009 Technology glossary for gaseous hydrogen, hydrogen energy and hydrogen energy system
1 Scope
This standard puts forward the terms and definitions of gaseous hydrogen, hydrogen energy and hydrogen energy system technology and its application.
This standard is applicable to the formulation of technical standards, preparation of technical documents, compilation and translation of professional manuals, teaching materials, books and periodicals for gaseous hydrogen, hydrogen energy and hydrogen energy system.
2 General terms
2.1
hydrogen
lightest chemical element, expressed by symbol H, with atomic number of 1 and an atomic weight of 1.008, which is an important component element of the Earth
2.2
hydrogen energy
energy released by hydrogen during physical and chemical changes, which can be used for power generation or as fuels for various vehicles and aircrafts, household fuels, etc.
2.3
hydrogen energy system
generic term for hydrogen production, storage, transportation, distribution and application systems
2.4
chemistry of hydrogen energy
science of studying various chemical processes in the production, storage, transportation and application of hydrogen
2.5
hydrogen economy
economic structure composed of hydrogen production, transportation, storage, transformation and application, and related standards and specifications
2.6
hydrogen atom
atom consisting of a proton and an electron
2.7
hydrogen molecule
molecule consisting of two hydrogen atoms bonded together by chemical bonds
2.8
hydrogen ion
ion that is formed when a hydrogen atom loses its electron
2.9
protium
isotope of hydrogen, expressed by 1H, with proton number of 1, which is an important component of hydrogen molecule with a relative proton mass of 1.007 8
2.10
deuterium
isotope of hydrogen, expressed by 2D, consisting of a neutron and a proton, with a relative proton mass of 2.014 1
2.11
tritium
isotope of hydrogen, expressed by 3T, consisting of two neutrons, with proton number of 1 and a relative proton mass of 3.010 05
2.12
orthohydrogen
isomer of hydrogen molecule in which the spin directions of nuclei are the same (parallel)
2.13
parahydrogen
isomer of hydrogen molecule in which the spin directions of nuclei are opposite (anti-parallel)
2.14
hydrogen bond
intramolecular or intermolecular attraction as a result of hydrogen atom attracting the lone pair electrons of the adjacent highly electronegative atom in the polar compound of hydrogen
2.15
gaseous hydrogen
hydrogen molecule in gaseous form
2.16
compressed gaseous hydrogen
gaseous hydrogen at a pressure higher than atmospheric pressure
2.17
wet hydrogen
gaseous hydrogen with saturated or supersaturated water content at certain temperature and pressure
2.18
liquid hydrogen
hydrogen in liquid form, which is a colorless and transparent cryogenic liquid, with normal boiling point of 20.38 K and density at boiling point of 70.77 kg/m3
2.19
solid hydrogen
white solid floc condensed by diatomic molecules of gaseous hydrogen, with density of 80.7 kg/m3 (11.15 K) and melting point of 14.01 K
2.20
hydrogen low heat value
heat released by water that is generated after unit mass of hydrogen is completely burned and does not condense into liquid water. The low heat value of hydrogen is 120.0 MJ/kg.
2.21
hydrogen high heat value
heat released by water that is generated after unit mass of hydrogen is completely burned and condenses into liquid water totally. The high heat value of hydrogen is 141.86 MJ/kg.
2.22
gaseous hydrogen diffusion
process of gaseous hydrogen dispersion, expansion and spreading with the change of environmental state
2.23
gaseous hydrogen leakage
process of gaseous hydrogen seeping out from closed systems, equipment and pipelines to the outside
Foreword i 1 Scope 2 General terms 3 Production of gaseous hydrogen 4 Storage, transportation and filling of gaseous hydrogen 5 Application of hydrogen energy 6 Safety of hydrogen energy system Annex A (Informative) Explanation of provisions Annex B (Informative) Index in Chinese Annex C (Informative) Index in English
