Organic matter in a state of advanced decay, after passing through the stages of COMPOST and PEAT and before becoming lignite (COAL). It is composed of a heterogenous mixture of compounds including phenolic radicals and acids that polymerize and are not easily separated nor analyzed. (E.A. Ghabbour & G. Davies, eds. Humic Substances, 2001).
Garbage, refuse, or sludge, or other discarded materials from a wastewater treatment plant, water supply treatment plant, and air pollution control facility that include solid, semi-solid, or contained material. It does not include materials dissolved in domestic sewage, irrigation return flows, or industrial discharges.
A mass of organic or inorganic solid fragmented material, or the solid fragment itself, that comes from the weathering of rock and is carried by, suspended in, or dropped by air, water, or ice. It refers also to a mass that is accumulated by any other natural agent and that forms in layers on the earth's surface, such as sand, gravel, silt, mud, fill, or loess. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed, p1689)
Encyclopedias as Topic
The presence of bacteria, viruses, and fungi in the soil. This term is not restricted to pathogenic organisms.
An excited state of molecular oxygen generated photochemically or chemically. Singlet oxygen reacts with a variety of biological molecules such as NUCLEIC ACIDS; PROTEINS; and LIPIDS; causing oxidative damages.
A plant genus in the LAURACEAE family. Laurus nobilis L. leaves are known for use in SPICES, having a similar flavor as UMBELLULARIA.
A geographical area of the United States comprising the District of Columbia, Delaware, Maryland, New Jersey, New York, and Pennsylvania.
Spectroscopy, Fourier Transform Infrared
Quaternary Ammonium Compounds
Addition of methyl groups. In histo-chemistry methylation is used to esterify carboxyl groups and remove sulfate groups by treating tissue sections with hot methanol in the presence of hydrochloric acid. (From Stedman, 25th ed)