NE X T to trimethylamine, ammonia is the most typical spoilage product in fish, molluscs and crustaceans. I t is generally determined together with other volatile nitrogen bases, as total volatile basic nitrogen (TVB). The objective quality determinations of cartilaginous fish such as dogfish and skate, however, raises special problems. These fish contain large quantities of urea (1.5 to 2 per ...

things. There was no flora, no fauna; the Earth was completely barren of life. Instead of having an atmosphere rich in nitrogen and oxygen as it is today, the atmosphere on primitive Earth was composed primarily of methane, ammonia, hydrogen gas and water vapor. The lack of a protective ozone layer resulted inhigh exposure to UV light and radiation. Earth was also extremely volcanically active ...

_Treating the wastewater with high level of urea and ammonia-nitrogen is one of the problems faced by urea fertilizer plants in Indonesia. The alternative treatment being studied is the one which uses Fenton oxidation process which is continued with the use of Pseudomonas fluorescens bacteria. This study is conducted with the concentration of ammonia-nitrogen of 2500 ppm, 2000 ppm, and 1500 ppm...

Ammonia-oxidizing archaea (AOA) are ubiquitous in various marine environments and play important roles in the global nitrogen and carbon cycles. We here present a high-quality draft genome sequence of an ammonia-oxidizing archaeon, "Candidatus Nitrosopumilus koreensis" AR1, which was found to dominate an ammonia-oxidizing enrichment culture in marine sediment off Svalbard, the Arctic Circle. De...

Urea metabolism was studied with nitrogen-starved cells of Chlorella vulgaris Beijerinck var. viridis (Chodat), a green alga which apparently lacks urease. Incorporation of radioactivity from urea-(14)C into the alcohol-soluble fraction was virtually eliminated in cell suspensions flushed with 10% CO(2) in air. This same result was obtained when expected acceptors of urea carbon were replenishe...

We introduce ammonia borane, a versatile reducing agent for graphene oxide (GO) reduction in both aqueous and organic solvents; it is nontoxic and more effective than hydrazine. More interestingly, ammonia borane reduction of GO tetrahydrofuran produced higher nitrogen- and boron-doped graphene that exhibited high supercapacitor performance.

Ammonia-oxidizing archaea (AOA) play important roles in nitrogen and carbon cycling in marine and terrestrial ecosystems. Here, we present the draft genome sequence for the ammonia-oxidizing archaeon "Candidatus Nitrosopumilus salaria" BD31, which was enriched in culture from sediments of the San Francisco Bay estuary. The genome sequences revealed many similarities to the genome of Nitrosopumi...

Plant growth is directly dependent upon an adequate supply of fixed nitrogen. Water and fixed nitrogen are the most common limiting factors for plant growth.There is an abundance of nitrogen in the atmosphere, but it is in the form of the relatively inert gas, N2, and this must be converted chemically or biologically into a more active form before plants can utilize it. Chemical fixation most c...

[1] Recent regulations require large-scale emission reductions of NOx and SO2 in the eastern United States. These emission changes will alter the partitioning of ammonia between the gas and particle phases. Furthermore, ammonia emissions are expected to increase in the future. How will these changes impact the contribution of ammonia to inorganic particulate matter and nitrogen deposition? We u...