[EN] The uses of hydrogen are mainly based on the chemical or petrochemical required for industrial processes such as in obtaining ammonia or oil respectively. Most of its production is from fossil fuel, specifically the ...

[ES] Este trabajo profundiza en la evolución de los usos sociales de la fotografía, concretamente, en aquellos que afectan a la institución familiar. Para ello, se han revisado los cambios que ha sufrido el concepto de ...