See:nitrocellulose
A rare monoclinic mineral, BaAl2 Si2 O8 ; feldspar
group; the barium analog of anorthite; dimorphous with paracelsian.
a. Designation of the degree on the International Practical Temperature
Scale; also used for the name of the scale, as "Celsius Temperature
Scale." Formerly (prior to 1948) called "Centigrade." The Celsius
temperature scale is related to the International Kelvin Temperature Scale
by the equation TC = TK - 273.16. ASTM
b. Symbol, C. Graduated to a scale of 100; of or pertaining to such a
scale. On the centigrade thermometer the freezing point of water is 0
degrees (C) and its boiling point is 100 degrees (C). If any degree on the
centigrade scale, either above or below 0 degrees C, is multiplied by 1.8,
the result will be, in either case, the number of degrees above or below
32 degrees F, or the freezing point of Fahrenheit. Standard, 2
a. A manufactured gray powder which when mixed with water makes a plastic
mass that will set or harden. It is combined with aggregate to make
concrete. Nearly all of today's production is portland cement.
See also:cement rock
b. To place cement in a borehole to seal off caves or fissures or to fill
cavities or caverns encountered in drilling.
c. Mineral material, usually chemically precipitated, that occurs in the
spaces among the individual grains of a consolidated sedimentary rock,
thereby binding the grains together as a rigid, coherent mass; it may be
derived from the sediment or its entrapped waters, or it may be brought in
by solution from outside sources. The most common cements are silica
(quartz, opal, chalcedony), carbonates (calcite, dolomite, siderite), and
various iron oxides. Others include clay minerals, barite, gypsum,
anhydrite, and pyrite. Detrital clay minerals and other fine clastic
particles may also serve as cements. AGI
d. A term used in gold-mining regions to describe various consolidated,
fragmental aggregates, such as breccia, conglomerate, and the like, that
are auriferous.
e. A finely divided metal obtained by precipitation. The word in this
sense is generally used in combination, such as, cement copper, cement
gold, or cement silver. Standard, 2
a. The diagenetic process by which coarse clastic sediments become
lithified or consolidated into hard, compact rocks, usually through
deposition or precipitation of minerals in the spaces among the individual
grains of the sediment. It may occur simultaneously with sedimentation or
at a later time. Cementation may occur by secondary enlargement.
Syn:agglutination
b. Filling cavities or plugging a drill hole with cement or other material
to stop loss of water or entrance of unwanted liquids, gas, or fragmented
rock materials. Also called dental work.
c. The process by which loose sediments or sands are consolidated into
hard rock by injection of chemical solutions, thin cement slurries, or
self-hardening plastic. Also called cementing. Long
d. The introduction of one or more elements into the outer portion of a
metal object by means of diffusion at high temperature. ASM, 1
e. The precipitation of a more noble metal from solution by the
introduction of a less noble metal.
f. Usually, the process of raising the carbon content of steel by heating
in a carbonaceous medium. Generally, any process in which the surface of a
metal is impregnated by another substance. Also called casehardening;
carburization; carbonization. CTD
A method of shaft sinking through water-bearing strata by injecting
chemicals or liquid cement into the ground. A number of small-diameter
boreholes are put down around the shaft--and about 80 ft (24 m) ahead of
the shaft bottom#m-through which cement is forced by means of pumps. The
cement, when set, seals the fissures and thus prevents water inflows
during sinking. The method is most successful in strong fissured strata
and least successful in loose alluvial deposits. See also:grouting;
precementation process. Nelson
Steel made by a process in which bars of wrought iron are packed into a
sealed furnace together with charcoal. The resulting material is blister
steel. Syn:cement steel
Water containing dissolved copper or iron sulfates or other metal
compounds. Stoces
Portland cement as it comes from the kiln.
Copper precipitated by iron from copper sulfate in mine water.
Bateman, 2
Cambrian conglomerate occupying supposedly old beaches or channels. It is
gold-bearing in the Black Hills, SD.
Generally, a mixture of powdered tungsten carbide and cobalt, subjected to
pressure and heat to produce bit crowns, small plates, cubes, or cylinders
of material having a much greater hardness than steel. Mixtures also may
contain small amounts of titanium, columbium, or tantalum carbide. Cobalt
may be replaced by powdered nickel. Also called sintered carbide.
See also:carbide insert; sintered carbide. Long
A tool made from pulverized carbides and fused into a hard tip for
heavy-duty or high-speed cutting of metals. Crispin
Gold precipitated in fine particles from solution by a more active metal.
Fay
A pumpable thin slurry consisting primarily of a mixture of cement, sand,
and water; injected into rock formations through boreholes as a sealant.
Also called grout; grouting; cement grouting. Long
A mechanical device for the application of cement, in the form of gunite,
to the walls or roofs of mine openings or building walls. Also called
gunite gun. Long
a. Identical with cohenite, a meteoritic material. Hey, 1
b. An orthorhombic FeC3 that occurs as a phase in steel and changes
composition in the presence of manganese or other carbide-forming metals.
See:cohenite
Having the property of or acting like cement, such as certain limestones
and tuffs when used in the surfacing of roads. AGI
The addition of small quantities of cement (1% to 2%) to fine-grained
soils to reduce the liquid limit, plasticity index, and water-absorption
tendency. The effect of the cement is to bring individual soil particles
into aggregations, thus artificially adjusting the grading of the soil.
See also:soil stabilization
Made from four (or less) parts of sand, one of cement, and adequate water.
Nelson
Hardened cement material filling a portion of a borehole. Long