Next page Previous page

adiabatic compression

Compression in which no heat is added to or subtracted from the air and
the internal energy of the air is increased by an amount equivalent to the
external work done on the air. The increase in temperature of the air
during adiabatic compression tends to increase the pressure on account of
the decrease in volume alone; therefore, the pressure during adiabatic
compression rises faster than the volume diminishes. Lewis

adiabatic efficiency

A compression term obtained by dividing the power theoretically necessary
to compress the gas and deliver it without loss of heat, by the power
supplied to the fan or compressor driveshaft.

adiabatic expansion

Expansion in which no heat is added to or subtracted from the air, which
cools during the expansion because of the work done by the air.
Lewis

adiabatic temperature

The temperature that would be attained if no heat were gained from or lost
to the surroundings. Newton, 1

adiabatic temperature change

The compression of a fluid without gain or loss to the surroundings when
work is performed on the system and produces a rise of temperature. In
very deep water such a rise of temperature occurs and must be considered
in the vertical temperature distribution. Hy

adinole

An argillaceous sediment that has undergone albitization as a result of
contact metamorphism along the margins of a sodium-rich mafic intrusion.
CF:spilosite; spotted slate. AGI

adipite

An aluminosilicate of calcium, magnesium, and potassium having the
composition of chabazite. Dana, 1

adipocerite

See:hatchettite

adipocire

See:hatchettite

a direction

See:a axis

adit

a. A horizontal or nearly horizontal passage driven from the surface for
the working or dewatering of a mine. If driven through the hill or
mountain to the surface on the opposite side, it would be a tunnel.
Syn:drift; adit level. See also:tunnel
b. As used in the Colorado statutes, it may apply to a cut either open or
undercover, or open in part and undercover in part, dependent on the
nature of the ground.
c. A passage driven into a mine from the side of a hill.
Statistical Research Bureau

adit end

The furthermost end or part of an adit from its beginning or the very
place where the miners are working underground toward the mine.
Hess

adit level

Mine workings on a level with an adit. See also:adit

adjacent sea

A sea adjacent to and connected with the oceans, but semienclosed by land.
The North Polar, Mediterranean, and Caribbean Seas are examples.
Syn:marginal sea

adjustment of error

Method of distributing the revealed irregularities over a series of
results. Pryor, 3

adjutage

Nozzle or tube from which hydraulic water is discharged. Syn:ajutage

admission

See:admittance

admittance

a. In a crystal structure, substitution of a trace element for a major
element of higher valence; e.g., Li+ for Mg2+ . Admitted
trace elements generally have a lower concentration relative to the major
element in the mineral than in the fluid from which the mineral
crystallized. CF:capture; camouflage. Syn:admission
b. The reciprocal of impedance or the ratio of complex current to voltage
in a linear circuit. AGI

adobe

A fine-grained, usually calcareous, hard-baked clayey deposit mixed with
silt, usually forming as sheets in the central or lower parts of desert
basins, as in the playas of the southwestern United States and in the arid
parts of Mexico and South America. It is probably a windblown deposit,
although it is often reworked and redeposited by running water.
AGI

adobe charge

A mud-covered or unconfined explosive charge fired in contact with a rock
surface without the use of a borehole. Syn:bulldoze; mudcapping.
Atlas

adobe flat

A generally narrow plain formed by sheetflood deposition of fine sandy
clay or adobe brought down by an ephemeral stream, and having a smooth,
hard surface (when dry) usually unmarked by stream channels. AGI