Nitrous oxide (N 2 O) A powerful greenhouse gas with a global warming potential
of 298 times that of carbon dioxide (CO 2 ). Major sources of nitrous oxide include
soil cultivation practices, especially the use of commercial and organic fertilizers,
fossil fuel combustion, nitric acid production, and biomass burning. The GWP is
from the IPCC’s Fourth Assessment Report (AR4). Natural emissions of N 2 O are
mainly from bacteria breaking down nitrogen in soils and the oceans. Nitrous
oxide is mainly removed from the atmosphere through destruction in the stratosphere by ultraviolet radiation and associated chemical reactions, but it can also
be consumed by certain types of bacteria in soils.
NOAA Weather Radio A radio with a special receiver to receive information from
the network of radio stations that broadcast continuous weather information from
the National Weather Service.
Nocardia It is a group of irregularly bent, short branching filamentous organisms
that cause dense dark foam in aeration basins. Associated with high fats, oils, and
greases. Easily identified under a microscope.
Nonionic polymer A neutrally charged colloidal big organic substance used as a
coagulant to aid in separating (settling or floating) solids in water or wastewater
Nonmethane volatile organic compounds (NMVOCs) Organic compounds,
other than methane, that participate in atmospheric photochemical reactions.
Nonstructural elements Any portion of the building or grounds not connected to
the main structure (e.g., bookshelves, file cabinets, furnishings).
NPDES permit National Pollutant Discharge Elimination System (NPDES) permit
is the US regulatory agency document issued by either a federal or state agency
which is designed to control all discharges of pollutants from all point sources and
storm water runoff into US waterways. A treatment plant that discharges to a
surface water will have a NPDES permit.
Nutrient ratio The ratio of carbon, nitrogen, phosphorus and sometimes other trace
elements that is essential to optimum growth of the biomass in activated sludge.
Nutrient A substance that is taken in by organisms and promotes growth. Carbon,
nitrogen, and phosphorus are essential nutrients to most aquatic organisms.
Ocean acidification Increased concentrations of carbon dioxide in sea water causing a measurable increase in acidity (i.e., a reduction in ocean pH). This may lead
to reduced calcification rates of calcifying organisms such as corals, mollusks,
algae and crustaceans.
Organic A volatile, combustible, or biodegradable compound containing carbon
bound with other elements.
Organic nitrogen It is an organic nutrient containing nitrogen which is chemically
bound in organic molecules such as proteins, amines, and amino acids. It is
calculated by subtracting the Ammonia Nitrogen analysis results from Total
Kjeldahl Nitrogen analysis results.
Organic phosphate (a) It is a molecule of phosphate combined with an organic
compound. Total phosphorus includes orthophosphate, polyphosphate and
organic phosphate. (b) It is an organic phosphorus originating from organic
sources, such as body and food waste, and sometimes industrial sources. Some
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of 298 times that of carbon dioxide (CO 2 ). Major sources of nitrous oxide include
soil cultivation practices, especially the use of commercial and organic fertilizers,
fossil fuel combustion, nitric acid production, and biomass burning. The GWP is
from the IPCC’s Fourth Assessment Report (AR4). Natural emissions of N 2 O are
mainly from bacteria breaking down nitrogen in soils and the oceans. Nitrous
oxide is mainly removed from the atmosphere through destruction in the stratosphere by ultraviolet radiation and associated chemical reactions, but it can also
be consumed by certain types of bacteria in soils.
NOAA Weather Radio A radio with a special receiver to receive information from
the network of radio stations that broadcast continuous weather information from
the National Weather Service.
Nocardia It is a group of irregularly bent, short branching filamentous organisms
that cause dense dark foam in aeration basins. Associated with high fats, oils, and
greases. Easily identified under a microscope.
Nonionic polymer A neutrally charged colloidal big organic substance used as a
coagulant to aid in separating (settling or floating) solids in water or wastewater
Nonmethane volatile organic compounds (NMVOCs) Organic compounds,
other than methane, that participate in atmospheric photochemical reactions.
Nonstructural elements Any portion of the building or grounds not connected to
the main structure (e.g., bookshelves, file cabinets, furnishings).
NPDES permit National Pollutant Discharge Elimination System (NPDES) permit
is the US regulatory agency document issued by either a federal or state agency
which is designed to control all discharges of pollutants from all point sources and
storm water runoff into US waterways. A treatment plant that discharges to a
surface water will have a NPDES permit.
Nutrient ratio The ratio of carbon, nitrogen, phosphorus and sometimes other trace
elements that is essential to optimum growth of the biomass in activated sludge.
Nutrient A substance that is taken in by organisms and promotes growth. Carbon,
nitrogen, and phosphorus are essential nutrients to most aquatic organisms.
Ocean acidification Increased concentrations of carbon dioxide in sea water causing a measurable increase in acidity (i.e., a reduction in ocean pH). This may lead
to reduced calcification rates of calcifying organisms such as corals, mollusks,
algae and crustaceans.
Organic A volatile, combustible, or biodegradable compound containing carbon
bound with other elements.
Organic nitrogen It is an organic nutrient containing nitrogen which is chemically
bound in organic molecules such as proteins, amines, and amino acids. It is
calculated by subtracting the Ammonia Nitrogen analysis results from Total
Kjeldahl Nitrogen analysis results.
Organic phosphate (a) It is a molecule of phosphate combined with an organic
compound. Total phosphorus includes orthophosphate, polyphosphate and
organic phosphate. (b) It is an organic phosphorus originating from organic
sources, such as body and food waste, and sometimes industrial sources. Some
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M.-H. S. Wang and L. K. Wang