THE SULFUR-OXIDIZING PROKARYOTES. Biological oxidation of hydrogen sulfide to sulfate is one of the major reactions of the global sulfur cycle. Reduced inorganic sulfur compounds (referred to below as sulfur) are exclusively oxidized by prokaryotes, and sulfate is the major oxidation product. Sulfur oxidation in members of theEukarya is mediated by lithoautotrophic bacterial endosymbionts (44).
In simpler terms: the dew point, or frost point, is the temperature at which dew or frost will form should the air temperature fall sufficiently. Other things being equal, as the temperature falls, the relative humidity rises, reaching 100% at the dew point, at least at ground level.ew point temperature is never greater than the air temperature, since the relative humidity cannot exceed 100%.
Warm air can hold more water than cool air. But if the air (warm or cool) is holding half as much moisture as it can hold when saturated, the relative humidity is 50 percent. Meteorologists, in contrast, use dewpoint temperature as a measure of the moisture content of air. This is the temperature below which the air can no longer hold the moisture in vapor form and liquid water or dew will form. This phenomenon is illustrated by a glass of cool iced tea on a warm muggy day.