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> Greater than. DO
>5 mg/L would be read as:
DO greater than 5 mg/L.
< Less than. DO
<4 mg/L would be read as:
DO less than 4 mg/L.
| A | A B C D E F G H I J K L M N O P Q R S T U V W X Y Z |
The
taking in or soaking up of one substance into the body of another by molecular or chemical action (as tree roots
absorb dissolved nutrients in the soil).
How closely an instrument measures the true or actual value of the process
variable being measured or sensed.
(1)
A substance that tends to lose an electron.
(2) A substance that dissolves in water with the formation of hydrogen ions.
(3) A substance containing hydrogen which may be replaced by metals to form salts.
(4) A substance that is corrosive.
The condition of water or soil which contains a sufficient amount of acid substances to lower the pH below 7.0
The
addition of an acid (usually nitric or sulfuric) to a sample to lower the pH below 2.0.
The purpose of acidification is to “fix” a sample so it won’t change until
it is analyzed.
The quantitative capacity of aqueous solutions to react with hydroxyl ions. It is measured by titration with a standard solution of a base to a specified end point. Usually expressed as milligrams per liter of calcium carbonate.
The material being removed by the adsorption process.
The material (activated carbon) that is responsible for removing the undesirable
substance in the adsorption process.
The
gathering of a gas, liquid, or dissolved substance on the surface or interface zone of another material.
Pumping
dry air (dew point -40 °
F) into a container to assist with the withdrawal of a liquid or to
force a liquefied gas such as chlorine out of a container.
A
treatment process used to remove dissolved gases and volatile substances from water.
Large volumes of air are bubbled through the water being treated to remove
(strip out) the dissolved gases and volatile substances.
Microscopic
plants which contain chlorophyll and live floating or suspended in water.
They also may be attached to structures, rocks or other submerged surfaces. Excess
algal growths can impart tastes and odors to potable water.
Algae produce oxygen during sunlit times and use oxygen during dark times. Their
biological activities appreciably affect the pH and dissolved oxygen of the water.
ALIPHATIC HYDROXYL ACIDS (AL-uh-FAT-ick)
Organic acids with carbon atoms arranged in branched or unbranched open chains
rather than in rings.
Portion of a sample. Often an equally divided portion of a sample.
Any of certain soluble salts, principally of sodium, potassium, magnesium and calcium, that have the property of combining with acids to form neutral salts and may be used in chemical water treatment processes.
The condition of water or soil which contains a sufficient amount of acid substances to lower the pH above 7.0
The
capacity of water to neutralize acids.
This capacity is caused by the water’s content of carbonate, bicarbonate,
hydroxide, and occasionally borate, silicate, and phosphate.
Alkalinity is express in milligrams per liter of equivalent calcium carbonate. Alkalinity
is not the same as pH because water does not have to be strongly basic (high pH) to have a high alkalinity. Alkalinity
is a measure of how much acid must be added to a liquid to lower the pH to 4.5 SU.
AMBIENT TEMPERATURE (AM-bee-ent)
Temperature of the surroundings. Temperature of the surrounding air (or other medium). For example, temperature of the room where a gas chlorinator is installed.
AMPEROMETRIC (am-PURR-o-MET-rick)
A
method of measurement that records electric current flowing or generated, rather than recording voltage. Amperometric
titration is a means of measuring concentrations of certain substances in water.
A means of measuring concentrations of certain substances in water (such
as strong oxidizers) based on the electric current that flows during a chemical reaction.
See TITRATION.
ANAEROBIC ENVIRONMENT (AN-air-O-bick)
A
condition in which “free” (atmospheric) or molecular (dissolved) oxygen is NOT present in the aquatic (water) environment.
The readout of an instrument by a pointer (or other indicating means) against
a dial or scale.
A device which conducts periodic or continuous measurement of some factor
such as chlorine, fluoride or turbidity.
Analyzers operate by any of several methods including photocells, conductivity
or complex instrumentation.
a unit of length equal to one-tenth of a nanometer or one - ten billionth
of a meter. One Angstrom is the approximate diameter of an atom.
A negatively charged ion in an electrolyte solution, attracted to the anode under the influence of a difference in electrical potential.
The positive terminal of an electrolytic cell.
Free
from the living germs of disease, fermentation or putrefaction.
Sterile.
The
smallest unit of a chemical element; composed of protons, neutrons and electrons.
Hydrogen, 1H, has one proton and one electron. Deuterium, 2H, has one proton and one neutron and one electron. Deuterium Oxide, D2O, is called heavy water.
Among the moderators that have been used in nuclear reactors are carbon in
the form of graphite, the light metal beryllium, heavy water (having a deuterium nucleus), and ordinary water.
[1]
A feature of some newer pH meters that recognize, automatically, the buffers (4.01, 7.00 and 10.01 [within a range of ± 0.5 SU]) required for calibration.
Microorganisms which use inorganic materials for energy and growth. They derive carbon for their cellular growth from inorganic sources such as carbon dioxide and bicarbonate. Nitrosomonas and Nitrobacter (see Nitrification process) are two such naturally occuring microorganisms. Heterotrophs use ORGANIC matter for energy and growth.
The number equal to the number of Carbon atoms in exactly 12 grams of pure 12C. This number is called Avogadro’s number. It is 6.02 x 1023.
| B | A B C D E F G H I J K L M N O P Q R S T U V W X Y Z |
(1) A substance which takes up or accepts protons.
.
(2) A substance containing hydroxyl ions which reacts with an acid to form
a salt
or which may react with metals to form precipitates.
(3)
A substance which dissociates (separates) in aqueous solution to yield hydroxyl ions (OH ¯)
Bacteria are living organisms, microscopic in size, which usually consist of a single cell. Most bacteria use organic matter for their food and produce waste products as a result of their life processes.
(1) A
way of showing or measuring the effect of biological treatment on a
particular waste or substance, or
(2) A method of determining toxic effects of industrial wastes or other wastes by using live organisms such as fish for test organisms.
A term used to describe methods of evaluating or measuring the effects of toxic substances in effluents on aquatic organisms in receiving waters. There are two types of biomonitoring, the biosurvey and the bioassay.
An
accounting of the types and numbers of organisms naturally present in the receiving waters upstream and downstream
from plant effluents.
Comparisons are made between the aquatic organisms upstream and downstream
of the discharge.
A
bottle containing only dilution water or distilled water, but the sample being tested is not added. Tests
are frequently run on a sample and a blank and the differences compared.
Biochemical Oxygen Demand, BOD
Biochemical Oxygen Demand.
The rate at which organisms use the oxygen in water while stabilizing decomposable
organic matter under aerobic conditions.
In decomposition, organic matter serves as food for the bacteria and energy
results from its oxidation.
BOD measurements are used as a measure of the organic strength of wastes
in water.
The quantity of oxygen used in the biochemical oxidation of organic matter
in a specified time, at a specified temperature, and under specified conditions.
A standard test used in assessing wastewater strength.
A solution or liquid whose chemical makeup neutralizes acids or bases without a great change in pH. Any of certain combinations of chemicals used to stabilize the pH values or alkalinities of solutions.
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