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Bismuth minerals

Many types of bismuth mineral salts (e.g., bismuth subsalicylate) are generally multipurpose intestinal medicinal agents. As an antisecretory agent, bismuth subsalicylate coats and protects irritated and inflamed intestinal lumen tissue (antiulcer actions), decreases the secretion of fluid into the intestine, absorbs or neutralizes bacterial toxins, inhibits any bacterial activity (antidiarrhea actions), and also increases alkaline secretion to counteract any acid production (antacid action). Thus, this agent controls the frequent voluminous loss of watery stools while relieving intestinal cramping and irritation. [Pg.77]

Miller, R., Kawazulite Bi2Te2Se, related bismuth minerals and selenian covellite from the Northwest Territories, Can. Mineral, 19, (1981), 341-348. Cited on pages 635, 637. [Pg.745]

This is a radioactive element. It occurs in minute traces in barium and thorium minerals, but it can be produced by irradiation of bismuth in a nuclear reactor. (The study of its chemistry presents great difficulty because of its intense a radiation). [Pg.262]

Gr. aktis, aktinos, beam or ray). Discovered by Andre Debierne in 1899 and independently by F. Giesel in 1902. Occurs naturally in association with uranium minerals. Actinium-227, a decay product of uranium-235, is a beta emitter with a 21.6-year half-life. Its principal decay products are thorium-227 (18.5-day half-life), radium-223 (11.4-day half-life), and a number of short-lived products including radon, bismuth, polonium, and lead isotopes. In equilibrium with its decay products, it is a powerful source of alpha rays. Actinium metal has been prepared by the reduction of actinium fluoride with lithium vapor at about 1100 to 1300-degrees G. The chemical behavior of actinium is similar to that of the rare earths, particularly lanthanum. Purified actinium comes into equilibrium with its decay products at the end of 185 days, and then decays according to its 21.6-year half-life. It is about 150 times as active as radium, making it of value in the production of neutrons. [Pg.157]

Alaska, Washington, and Nevada. Ores of the Southeast Missouri lead belt and extensive deposits such as in Silesia and Morocco are of the replacement type. These deposits formed when an aqueous solution of the minerals, under the influence of changing temperature and pressure, deposited the sulfides in susceptible sedimentary rock, usually limestone and dolomites. These ore bodies usually contain galena, sphalerite, and pyrite minerals, but seldom contain gold, silver, copper, antimony, or bismuth. [Pg.32]

Some elements found in body tissues have no apparent physiological role, but have not been shown to be toxic. Examples are mbidium, strontium, titanium, niobium, germanium, and lanthanum. Other elements are toxic when found in greater than trace amounts, and sometimes in trace amounts. These latter elements include arsenic, mercury, lead, cadmium, silver, zirconium, beryUium, and thallium. Numerous other elements are used in medicine in nonnutrient roles. These include lithium, bismuth, antimony, bromine, platinum, and gold (Eig. 1). The interactions of mineral nutrients with... [Pg.373]

Mineral Industry Surveys, Bismuth Annual Keview, U.S. Bureau of Mines, Washington, D.C., 1990. [Pg.125]

Cobalt is the thirtieth most abundant element on earth and comprises approximately 0.0025% of the earth s cmst (3). It occurs in mineral form as arsenides, sulfides, and oxides trace amounts are also found in other minerals of nickel and iron as substitute ions (4). Cobalt minerals are commonly associated with ores of nickel, iron, silver, bismuth, copper, manganese, antimony, and 2iac. Table 1 Hsts the principal cobalt minerals and some corresponding properties. A complete listing of cobalt minerals is given ia Reference 4. [Pg.369]

Oils, grease, hydrogen, flammable liquids, solids or gases Acetic anhydride, bismuth and its alloys, alcohol, paper, wood, grease, oils Acids (organic or mineral), avoid friction, store cold Air, oxygen... [Pg.233]

Main opaque minerals are chalcopyrite, cassiterite, stannite, arsenopyrite, bismuth-inite, pyrrhotite and sphalerite. The FeS content of sphalerite is high (about 18 mol% FeS). [Pg.233]

V. H. Aprahamian and D. G. Demopoulos, The Solution Chemistry and Solvent Extraction Behaviour of copper, iron, nickel, zinc, lead, tin, Ag, arsenic, antimony, bismuth, selenium and tellurium in Acid Chloride Solutions Reviewed from the Standpoint of PGM Refining, Mineral Processing and Extractive Metallurgy Review, Vol. 14, p. 143,1995. [Pg.579]

A number of substances may interfere with stool examination. Particulate materials such as barium, antacids, kaolin, and bismuth compounds interfere with morphologic examination, and oily materials such as mineral oil create small, refractile droplets that make examination difficult. Antimicrobial agents, particularly broad-spectrum antimicrobial agents, may suppress amebae. If any of these substances have been used, specimens should not be submitted until the substances have been cleared (generally 5 to 10 days). A fecal specimen may appear satisfactory by gross examination when there is still barium, etc., which can interfere with microscopic examination. [Pg.6]

Berndt et al. [740] have shown that traces of bismuth, cadmium, copper, cobalt, indium, nickel, lead, thallium, and zinc could be separated from samples of seawater, mineral water, and drinking water by complexation with the ammonium salt of pyrrolidine- 1-dithiocarboxylic acid, followed by filtration through a filter covered with a layer of active carbon. Sample volumes could range from 100 ml to 10 litres. The elements were dissolved in nitric acid and then determined by atomic absorption or inductively coupled plasma optical emission spectrometry. [Pg.261]

Mercaptoethanol reacts rapidly with most bismuth salts with the typical mineral acid metathesis to give bis(thiolate) Bi(SCH2 CH2OH)2X derivatives as the prominent and most easily isolated... [Pg.341]

Depending on the composition of disseminated and medium-coarse-grained ore, they can be divided into two basic groups sulphides and chloritic tourmaline ores. In the sulphide ore, the minerals are represented by pyrite, pyrrhotite, arsenopyrite, chalcopyrite, galena and stannin. Less common are sphalerite and bismuth. [Pg.89]

Occurrence. Nearly all the silver ores are compounds of silver with sulphur and the neighbours in the Periodic Table arsenic, antimony and bismuth (argentite Ag2S, the most common silver compound, pyrargyrite Ag3SbS3, proustite Ag3AsS3). Other silver minerals include the halides. Silver is found sometimes as the free metal. Secondary silver (from catalysts, scraps, photographic films, etc.) is an important source. [Pg.458]

Occurrence. Bismuth occurs in minerals such as bismite (Bi203), bismuthinite (Bi2S3), bismutite (Bi0)2(C03). [Pg.509]

Bismuth is the fifth element in the nitrogen group, and its properties are the most metal-like of the five. Elemental bismuth is a heavy, brittle, hard metal that can be polished to a bright gray-white coat with a pinkish hue. It is not found in this state very often because it is more likely to be combined with other metals and minerals, such as tin, lead, iron and cadmium. These are mixtures with low melting points, making them useful in fire-detection devices. [Pg.221]

Marcoux, E., Moelo, Y., Leistel, J.M. 1996. Bismuth and cobalt minerals as indicators of stringer zones to massive sulphide deposits, Iberian Pyrite Belt. Mineralium Deposita, 31, 1-26. [Pg.54]

Bismuth, which has been known since ancient times, was often confused with lead and tin. Basilius Valentinus described some of its uses in 1450, but it was in 1753 that bismuth was shown by Claude Francois Geoffroy to be a distinct element. Bismuth occurs freely in nature and in such minerals as bismuthinite (Bi2S3), bismite (Bi203), and bismutite KBiObCO i. ... [Pg.230]

Bismuth may be obtained from other ores, too. The recovery process however, depends primarily on the chemical nature of the ores. For example, the sulfide ore requires smelting, carbon reduction, and the addition of iron (to decompose any bismuth sulfide present). Oxide ores, on the other hand, are treated with hydrochloric acid to leach bismuth from the mineral. The bismuth chloride solution is then diluted with water to precipitate bismuth oxy-... [Pg.108]

Bismuth sulfide occurs in nature as the mineral bismuthinite (bismuth glance). It is used as a starting material to produce many other bismuth compounds. [Pg.114]

The compound occurs in nature as mineral bismuthinite. It can be prepared in the laboratory by passing hydrogen sulfide into a solution of bismuth chloride or any soluble bismuth salt ... [Pg.114]

Bismuth trioxide occurs in nature as mineral bismite. The oxide is used in fireproofing of papers and polymers in enameling cast iron ceramic and in disinfectants. [Pg.115]


See other pages where Bismuth minerals is mentioned: [Pg.74]    [Pg.3]    [Pg.334]    [Pg.97]    [Pg.74]    [Pg.3]    [Pg.334]    [Pg.97]    [Pg.443]    [Pg.383]    [Pg.56]    [Pg.130]    [Pg.548]    [Pg.341]    [Pg.82]    [Pg.251]    [Pg.60]    [Pg.118]    [Pg.39]    [Pg.497]    [Pg.503]    [Pg.301]    [Pg.343]    [Pg.106]    [Pg.106]    [Pg.115]    [Pg.47]   
See also in sourсe #XX -- [ Pg.1009 ]




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