See:bowenite
Former name for calciovolborthite.
a. A straight line that touches, but does not transect, a given curve or
surface at one and only one point; a line that touches a circle and is
perpendicular to its radius at the point of contact. AGI
b. The part of a traverse included between the point of tangency (the
point in a line survey where a circular curve ends and a tangent begins)
of one curve and the point of a curvature (the point in a line survey
where a tangent ends and a circular curve begins) of the next curve.
AGI
c. A great-circle line that is tangent to a parallel of latitude at a
township corner in the U.S. Public Land Surveys system. AGI
d. A term sometimes applied to a long straight line of a traverse whether
or not the termini of the line are points of curve. AGI
e. The ratio of the length of the leg opposite an acute angle in a
right-angled triangle to the length of the leg adjacent to the angle. Adj.
said of a line or surface that meets a curve or surface at only one point.
AGI
The distance from the point of curvature to the point of intersection
(vertex), or from the point of intersection to the point of tangency.
See also:intersection point
a. Stress parallel to the tangent to the boundary of any opening.
Obert
b. See:shear stress
The point at which a curve meets a straight line or another curve.
Hammond
A very fine, slow-motion screw giving a tangential movement for making the
final setting to a precision surveying instrument (such as for completing
the alignment of sight on a theodolite or transit by gentle rotation of
the reading circle about its axis). CF:Stebinger drum
A variety of serpentine used by the Maoris for ornaments. Similar to
bowenite. See also:bowenite
A term used by the Maoris of New Zealand for bowenite, a massive variety
of antigorite. Also spelled tangiwai or tangawaite.
Mica with intergrowths of crystals or laminae resulting in books that
split well in some places but tear to produce a large proportion of
partial films. Skow
a. A large vessel or receptacle, made either of wood or of metal, intended
to contain a fluid or gas, as water tank, gasoline tank. Syn:vat
Fay
b. A melting unit, in which the container for the molten glass is
constructed from refractory blocks. ASTM
a. The act or process of storing oil, etc., in a tank. Fay
b. The price charged or paid for storage in a tank. Fay
c. The capacity of a tank or tanks. Fay
d. The waste residue deposited in lixiviating vats or tanks. Fay
Essentially a large box of refractory material holding from 6 to 200 st
(5.4 to 181 t) of glass, through the sides of which are cut ports fed with
a combustile mixture (producer gas and air, coke oven gas and air, or oil
spray and air), so that flame sweeps over the glass surface. With the
furnace is associated a regenerative or recuperative system for the
purpose of recovering part of the heat from the waste gas. CTD
See:station
A mineral series ferrotantalite-manganotantalite; unless specified it
refers to ferrotantalite, an orthorhombic mineral, FeTa2 O6;
black; in pegmatites; the main source of tantalum.
A rather brittle, lustrous, hard, heavy, gray metallic element. Symbol,
Ta. Occurs principally in the mineral columbite-tantalite, (Fe,Mn)(Nb,Ta)
2 O6 . Widely used to fabricate chemical process equipment,
nuclear reactors, and aircraft and missile parts. Used to make
electrolytic capacitors, vacuum furnace parts, and surgical appliances.
Handbook of Chemistry and Physics, 3
Several borides are known, including the following: Ta B2 , melting
point, 3,200 degrees C; sp gr, 12.5; thermal expansion, 5.5 X 10 (super
-6) ; TaB, melting point, 2,400 degrees C; sp gr, 14.3; Ta3 B (sub
4) , melts incongruently at 2,650 degrees C; sp gr, 13.6. Dodd
Two nitrides are known: TaN, melting point, 3,090+ or -50 degrees C; Ta
2 N , which loses nitrogen at 1,900 degrees C. Dodd
An orthorhombic mineral, (Y,Ce,Ca)(Ta,Nb,Ti)2 (O,OH)6 ;
black. Syn:delorenzite
A possibly triclinic mineral, Ti2 O5 .
A blue to violet gem variety of zoisite.