A standard 9-in by 4-1/2-in by 2-1/2-in (22.9-cm by 11.4-cm by 6.4-cm)
straight brick.
Final sample taken for test when a small quantity of finely ground mineral
is required for assay. A suitable quantity of dry material is thoroughly
mixed on glazed cloth or paper, if necessary, being rolled lightly with a
round bottle to break down any floccules. It is then flattened to a disk
and eight equal segments are marked out diametrically with a spatula.
Approx. equal quantities are taken from each segment and from the center,
making the nine points of withdrawal. Pryor, 3
An orthorhombic mineral, (U,Ca,Ce)2 (PO4 )2 .1-2H
2 O ; rhabdophane group; occurs in an unoxidized zone of the
Ningyo-toge Mine, Tottori prefecture, Japan.
See:columbite
A shiny, white, soft, and ductile metallic element. Symbol, Nb (niobium)
or Cb (columbium). The name niobium was adopted by the International Union
of Pure and Applied Chemistry. Many chemical societies and government
organizations refer to it as niobium, but most metallurgists, metals
societies, and commercial producers still refer to the metal as columbium.
Found in niobite (or columbite), niobite-tantalite, pyrochlore, and
euxenite. Used as an alloying agent in carbon and alloy steels, in
nonferrous metals, and in superconductive magnets. Syn:columbium
Handbook of Chemistry and Physics, 3
One of several compounds that have been reported, including the following:
NbB2 ; melting point, 3,050 degrees C; sp gr, 7.0; thermal
expansion, 5.9 X 10-6 parallel to a and 8.4 X 10-6
parallel to c; NbB, melting point, 2,300 degrees C; sp gr, 7.6; Nb3
B4 melts incongruently at 2,700 degrees C; sp gr, 7.3. Dodd
One of three nitrides that have been reported: NbN, Nb2 N , and Nb
4 N3 . During reaction between niobium and N2 at 800
to 1,500 degrees C the product generally consists of more than one
compound. Most of the phases are stable at least to 1,500 degrees C.
Dodd
a. Where the roof and the floor of a coal seam come close together
pinching the coal between them. CF:want
b. The contact ends of a cable for quick attachment to a power cable.
BCI
c. The device at the end of the trailing cable of a mining machine used
for connecting the trailing cable to the trolley wire and ground.
Jones, 1
d. To move a machine along a track by sliding the nip along the trolley
wire. Hess
e. The seizing of material between the jaws or rolls of a crusher.
Nichols, 1
f. See:angle of nip
g. To cut grooves at the end of a bar, to make it fit more evenly.
h. An undercutting notch in rock, particularly limestone, along a seacoast
between high- and low-tide levels produced by erosion or possible
solution. AGI
See:penthrite
A tubular pipe fitting usually threaded on both ends and under 12 in (30.5
cm) in length. Longer pipe is regarded as cut pipe.
See also:close nipple
A cast iron consisting of graphite in a matrix of austenite. It contains
3.0% carbon, 14.0% nickel, 6.0% copper, 2.0% chromium, and 1.5% silicon;
it has a high resistance to growth, oxidation, and corrosion. CTD
An orthorhombic mineral, 4[KNO3 ] ; water soluble; has a cooling
salty taste; a product of nitrification in most arable soils in hot, dry
regions, and in the loose earth forming the floors of some natural caves.
CF:nitratine
Crude sodium sulfate, a byproduct in the manufacture of nitric acid from
sodium nitrate. Fay
a. A salt of nitric acid; e.g., silver nitrate or barium nitrate.
Standard, 2
b. A mineral compound characterized by a fundamental anionic structure of
NO3- . Soda niter, NaNO3 , and niter, KNO3 ,
are nitrates. CF:carbonate; borate. AGI
c. Salts formed by the action of nitric acid on metallic oxides,
hydroxides, and carbonates. Readily soluble in water and decompose when
heated. The nitrates of polyhydric alcohols and the alkyl radicals explode
violently. CTD
A trigonal mineral, NaNO3 ; rhombohedral cleavage; water soluble
with a cooling taste; occurs only in very arid regions. Formerly called
soda niter.
The formation of nitrates by the oxidation of ammonium salts to nitrites
(usually by bacteria) followed by oxidation of nitrites to nitrates. It is
one of the processes of soil formation. AGI
An abbrev. for nitroglycerin or dynamite.
A monoclinic mineral, Ca(NO3 )2 .4H2 O ; water
soluble; soft; occurs as an efflorescence, e.g., on walls and in limestone
caves. Syn:wall saltpeter
Nitric acid esters of cellulose formed by the action of a mixture of
nitric and sulfuric acids on cellulose. The cellulose can be nitrated to a
varying extent, ranging from two to six nitrate groups in the molecule.
Nitrocellulose having a low nitrogen content, up to the tetranitrate, is
not explosive. They dissolve in ether-alcohol mixtures and in so-called
lacquer solvents, such as butyl acetate. A nitrocellulose having a high
nitrogen content is guncotton, an explosive. The principal nitrocellulose
plastic is celluloid. Syn:cellulose nitrate
A chemical combination of ordinary cotton fiber with nitric acid. It is
explosive, highly inflammable, and in certain degrees of nitration,
soluble in nitroglycerin.