Results 201 to 210 of about 28,122 (255)
Some of the next articles are maybe not open access.
Science (New York, N.Y.), 1972
Even granting our uncertainties about parts of our model of the sulfur cycle, we can draw some conclusions from it: 1) Man is now contributing about one half as much as nature to the total atmospheric burden of sulfur compounds, but by A.D. 2000 he will be contributing about as much, and in the Northern Hemisphere alone he will be more than matching ...
W W, Kellogg +4 more
openaire +3 more sources
Even granting our uncertainties about parts of our model of the sulfur cycle, we can draw some conclusions from it: 1) Man is now contributing about one half as much as nature to the total atmospheric burden of sulfur compounds, but by A.D. 2000 he will be contributing about as much, and in the Northern Hemisphere alone he will be more than matching ...
W W, Kellogg +4 more
openaire +3 more sources
Sulfuric Acid on Europa and the Radiolytic Sulfur Cycle
Science, 1999A comparison of laboratory spectra with Galileo data indicates that hydrated sulfuric acid is present and is a major component of Europa's surface. In addition, this moon's visually dark surface material, which spatially correlates with the sulfuric acid concentration, is identified as radiolytically altered sulfur polymers.
R W, Carlson +2 more
openaire +2 more sources
2005
Publisher Summary The chapter discusses the biologically mediated sulfur metabolisms, which involve the reduction of sulfur compounds, the oxidative processes, and the disproportionation of sulfur compounds. Sulfur is an essential nutrient element and constitutes around 0.5 to 1.0% of the dry weight of prokaryotic organisms.
Donald E. Canfield +2 more
openaire +1 more source
Publisher Summary The chapter discusses the biologically mediated sulfur metabolisms, which involve the reduction of sulfur compounds, the oxidative processes, and the disproportionation of sulfur compounds. Sulfur is an essential nutrient element and constitutes around 0.5 to 1.0% of the dry weight of prokaryotic organisms.
Donald E. Canfield +2 more
openaire +1 more source
Sulfur Cycling and the Intestinal Microbiome
Digestive Diseases and Sciences, 2017In this review, we focus on the activities transpiring in the anaerobic segment of the sulfur cycle occurring in the gut environment where hydrogen sulfide is produced. While sulfate-reducing bacteria are considered as the principal agents for hydrogen sulfide production, the enzymatic desulfhydration of cysteine by heterotrophic bacteria also ...
Barton, Larry +3 more
openaire +2 more sources
2014
This chapter addresses both geochemical and biogenic sulfur cycling, including their tight interconnections. It presents the cycling of sulfur between the atmosphere and the marine hydrosphere. The cycling involves redox processes and both biogenic and abiotic methylation and demethylation of sulfur.
openaire +1 more source
This chapter addresses both geochemical and biogenic sulfur cycling, including their tight interconnections. It presents the cycling of sulfur between the atmosphere and the marine hydrosphere. The cycling involves redox processes and both biogenic and abiotic methylation and demethylation of sulfur.
openaire +1 more source
2008
Microbes, especially bacteria, play an important role in oxidative and reductive cycle of sulfur. The oxidative part of the cycle is mediated by photosynthetic bacteria in the presence of light energy and chemosynthetic forms in the absence of light energy.
openaire +1 more source
Microbes, especially bacteria, play an important role in oxidative and reductive cycle of sulfur. The oxidative part of the cycle is mediated by photosynthetic bacteria in the presence of light energy and chemosynthetic forms in the absence of light energy.
openaire +1 more source
Biogeochemistry, 1984
Sulfur is essential for the production of certain amino acids in plants. As amino acid sulfur is the major form of sulfur in trees, there is a strong relationship between organic S and organic N in tree tissue. Sulfur deficiencies occur in parts of southeastern Australia and northwestern North America, remote from pollutant inputs.
openaire +1 more source
Sulfur is essential for the production of certain amino acids in plants. As amino acid sulfur is the major form of sulfur in trees, there is a strong relationship between organic S and organic N in tree tissue. Sulfur deficiencies occur in parts of southeastern Australia and northwestern North America, remote from pollutant inputs.
openaire +1 more source
1992
Publisher Summary Sulfur, the 14th most abundant element in the Earth's crust, plays a variety of important roles in the chemical functioning of the Earth. In its reduced oxidation state, sulfur is a key nutrient to life providing—for example, structural integrity to protein-containing tissues.
R.J. Charlson +2 more
openaire +1 more source
Publisher Summary Sulfur, the 14th most abundant element in the Earth's crust, plays a variety of important roles in the chemical functioning of the Earth. In its reduced oxidation state, sulfur is a key nutrient to life providing—for example, structural integrity to protein-containing tissues.
R.J. Charlson +2 more
openaire +1 more source
BIOGEOCHEMICAL CYCLES | Sulfur Cycle
2003This article is reproduced from the previous edition, volume 1, pp 213–220, © 2003, Elsevier Ltd.
openaire +1 more source
1973
The chemistry of gaseous sulfur compounds in the atmosphere at concentrations less than 0.1 ppm depends upon nonuniform distributions of sources and sinks as well as the variable physical properties of the atmosphere itself. Because of natural variations in sunlight intensity, temperature, humidity, surface chemical characteristics, and atmospheric ...
openaire +1 more source
The chemistry of gaseous sulfur compounds in the atmosphere at concentrations less than 0.1 ppm depends upon nonuniform distributions of sources and sinks as well as the variable physical properties of the atmosphere itself. Because of natural variations in sunlight intensity, temperature, humidity, surface chemical characteristics, and atmospheric ...
openaire +1 more source