bournonite is a sulfosalt mineral species, trithioantimoniate of lead and copper with the formula pbcusbs 3. it was first mentioned by philip rashleigh in 1797 as an ore of antimony and was more completely described in 1804 by french crystallographer and mineralogist jacques louis, comte de bournon 1751–1825 , after whom it was named.
a weighting agent such as barite is added to increase the overall density of the drilling fluid so that sufficient bottom hole pressure can be maintained thereby preventing an unwanted and often dangerous influx of formation fluids. also, use of silica and clay nanoparticles for high pressure high temperature hpht invert emulsion based muds .
bournonite is a sulfosalt mineral species, trithioantimoniate of lead and copper with the formula pbcusbs 3. 3 it was first mentioned by philip rashleigh in 1797 as an ore of antimony and was more completely described in 1804 by french crystallographer and mineralogist jacques louis, comte de bournon 1751–1825 , after whom it was named.
high nickel varieties are referred to as nickel-skutterudite, previously chloanthite. it is a hydrothermal ore mineral found in moderate to high temperature veins with other ni-co minerals. associated minerals are arsenopyrite , native silver , erythrite , annabergite , nickeline , cobaltite , silver sulfosalts , native bismuth , calcite , siderite , barite and quartz . 2
carpathite also pendletonite and karpatite is a very rare hydrocarbon mineral.it is the mineral form of the polycyclic aromatic hydrocarbon coronene with formula: c 24 h 12.. discovery. it was first described in 1955 for an occurrence in transcarpathian oblast, ukraine.it was named for the carpathian mountains.it has also been reported from the presov region of the slovak republic, the .
named after the city of skotterud, norway, skutterudite is a cobalt arsenide mineral containing variable amounts of nickel and iron substituting for cobalt with a general formula: coas 3.some references give the arsenic a variable formula subscript of 2-3. high nickel varieties are referred to as nickel-skutterudite, previously chloanthite.
the presence of pyrite in the aggregate used to make concrete can lead to severe deterioration as the pyrite oxidizes. in early 2009, problems with chinese drywall imported into the united states after hurricane katrina were attributed to oxidation of pyrite, which releases hydrogen sulfide gas.
the gastrointestinal tract digestive tract, alimentary canal, digestion tract, gi tract, git is an organ system within humans and other animals which takes in food, digests it to extract and absorb energy and nutrients, and expels the remaining waste as feces. the mouth, esophagus, stomach and intestines are part of the gastrointestinal tract.
in mineralogy, crystal habit is the characteristic external shape of an individual crystal or crystal group. a single crystal's habit is a description of its general shape and its crystallographic forms, plus how well developed each form is.. recognizing the habit may help in identifying a mineral.when the faces are well-developed due to uncrowded growth a crystal is called euhedral, one with .
gangue minerals include calcite, barite, and dolomite. it is regarded as a world-class rare-earth mineral deposit. the metals that can be extracted from it include: cerium, lanthanum, neodymium, and europium. in 2008, remaining reserves using a 5% cutoff grade were estimated to exceed 20 million tons of ore that averages 8.9% rare-earth oxides.
calcium bentonite may be converted to sodium bentonite termed sodium beneficiation or sodium activation to exhibit many of sodium bentonite's properties by an ion exchange process. in common usage, this means adding 5–10% of a soluble sodium salt such as sodium carbonate to wet bentonite, mixing well, and allowing time for the ion exchange to take place and water to remove the exchanged calcium.
prior to 1999, tarmac plc was an aggregates to construction company dating from 1903. it was demerged in july 1999, with the construction and professional services arms forming carillion plc. the aggregates and building materials side of the business retained the tarmac name and was bought by anglo american shortly afterwards.
soil aggregate stability is a measure of the ability of soil aggregates to resist degradation when exposed to external forces such as water erosion and wind erosion, shrinking and swelling processes, and tillage papadopoulos, 2011; usda, 2008 .soil aggregate stability is a measure of soil structure six et al., 2000a and can be impacted by soil management six et al., 1998
cordite is a family of smokeless propellants developed and produced in the united kingdom since 1889 to replace gunpowder as a military propellant. like gunpowder, cordite is classified as a low explosive because of its slow burning rates and consequently low brisance.these produce a subsonic deflagration wave rather than the supersonic detonation wave produced by brisants, or high explosives.