scispace - formally typeset
Search or ask a question
Topic

Ammonia

About: Ammonia is a research topic. Over the lifetime, 16217 publications have been published within this topic receiving 271940 citations. The topic is also known as: NH3 & azane.


Papers
More filters
Journal ArticleDOI
TL;DR: In this paper, the partitioning of reactive nitrogen compounds between the gas and the aerosol phase, as observed during the MINOS (Mediterranean INtensive Oxidant Study) campaign in Crete, Greece, in July and August 2001, has been studied with three thermodynamic gas-aerosol equilibrium models (EQMs) of different chemical complexity: ISORROPIA, which is limited to the ammonium-sulfate-nitrate-sodium-chloride-water-system; SCAPE2, which also includes mineral elements (
Abstract: The partitioning of reactive nitrogen compounds between the gas and the aerosol phase, as observed during the MINOS (Mediterranean INtensive Oxidant Study) campaign in Crete, Greece, in July and August 2001, has been studied with three thermodynamic gas-aerosol equilibrium models (EQMs) of different chemical complexity: ISORROPIA, which is limited to the ammonium-sulfate-nitrate-sodium-chloride-water-system; SCAPE2, which also includes mineral elements (calcium, magnesium and potassium); and EQSAM2, which additionally accounts for organic acids. The different EQMs are constrained by measured gas (g) and aerosol (a) concentrations: Total ammonia (NH 3(g) and NH 4(a) + ), total nitrate (HNO 3(g) and NO 3(a) - ), total sulfate (H 2 SO 4(g) and SO 4(a) 2- ), total chloride (HCl (g) and Cl - (a) ), sodium (Na + (a) ), calcium (Ca 2+ (a) ), magnesium (Mg 2+ (a) ), potassium (K + (a) ) and organic acids (a). Although the three EQMs differ considerably in particular aspects, their application at the same level of complexity yields comparable results for the equilibrium composition and phase partitioning of ammonia and nitric acid, i.e. within the range of measurement uncertainties (~10%). Their application at different levels of complexity, however, gives rise to substantial differences for the gas-aerosol partitioning of reactive nitrogen compounds. Our results show that only if (soluble) mineral components and (lumped) organic acids are accounted for, the observed gas-aerosol partitioning of ammonia and nitric acid can be accurately reproduced for air pollution episodes characterized by a complex chemical mixture, typical for the Mediterranean lower atmosphere.

113 citations

Journal ArticleDOI
TL;DR: In this paper, the yield of ammonia was found to depend on the nature, amount of metal and the method of metallization, and an optimum metal content is beneficial for the activity.
Abstract: Noble metal loaded TiO2 catalysts have been employed as catalysts for the photocatalytic reduction of nitrite and nitrate ions to ammonia. The yield of ammonia was found to depend on the nature, amount of metal and the method of metallization. An optimum metal content is beneficial for the activity. Beyond the optimum content the activity decreases.

113 citations

Journal ArticleDOI
TL;DR: It is proposed that during active phenylpropanoid metabolism, the ammonia released by phenylalanine ammonia lyase/tyrosine ammonia Lyase is efficiently recycled back to Phe/Tyr with glutamate serving as aminoreceptor and donor, the first evidence for a novel nitrogen cycle in plants.

113 citations

Journal ArticleDOI
TL;DR: In this article, the potential of a natural Australian zeolite, clinoptilolite to remove ammonium from water was investigated, using pure solutions, to investigate the equilibria and kinetic characteristics of ammonium exchange in the zeolisite Binary equilibrium experiments provided information on the adsorption characteristics of the zeolites in terms of ammonia capacity at varying solution concentrations.
Abstract: This study considered the potential of a natural Australian zeolite, clinoptilolite, to remove ammonium from water Ammonium-exchange capacity and rates of adsorption are critical to the assessment of the feasibility of the zeolite for application to continuous wastewater treatment A laboratory study was undertaken, using pure solutions, to investigate the equilibria and kinetic characteristics of ammonium exchange in the zeolite Binary equilibrium experiments provided information on the adsorption characteristics of the zeolite in terms of ammonia capacity at varying solution concentrations These experiments also revealed that the highest ammonium removal efficiency was achieved when the zeolite's exchange sites were converted to the sodium form Multicomponent equilibrium experiments were carried out to determine the effects of competing cations on the ammonium-exchange capacity of the zeolite The laboratory study indicated the zeolite's selectivity for ammonium ions over other cations typically pre

113 citations

Journal ArticleDOI
TL;DR: In this paper, a photocatalytic synthesis of ammonia from water and nitrogen was performed using binary wafered catalysts prepared with semiconductor powder (TiO2, SrTiO3, CdS or GaP).

113 citations


Network Information
Related Topics (5)
Carbon
129.8K papers, 2.7M citations
86% related
Adsorption
226.4K papers, 5.9M citations
85% related
Aqueous solution
189.5K papers, 3.4M citations
84% related
Hydrogen
132.2K papers, 2.5M citations
83% related
Amino acid
124.9K papers, 4M citations
83% related
Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20231,701
20223,035
2021425
2020443
2019496
2018511