With talc

Talc of metasedimentary origin is formed by hydrothermal alteration of a dolomitic host rock by a silica-containing fluid. This type of deposit is typical of Montana and AustraUa. It is usually quite pure with talc content of 90 to 98% and often very white as well. Dolomite [17069-72-6], CaMg(C02)2, is the most common accessory mineral. The fourth type is of metamorphic origin, where a siUcaceous dolostone is first converted to tremolite [14567-73-8] or actinohte [13768-00-8] and then partially converted to talc. The Balmat, New York, and Death Valley, California, deposits are of this type. Tremolite, dolomite, and serpentine are common accessory minerals. This type of talc deposit has a variable talc content (30—80%), but is usually white and often commercially exploited because of the properties of its accessory minerals rather than the talc. 

Regularly interstratified (1 1) chlorite and vermiculite has been attributed to the mineral corrensite [12173-14-7] (141). Chlorite mixed layers have been documented with talc, vermicuhte, smectite, iUite, biotite, kaolinite, serpentine, and muscovite. The mixed-layer mineral is named after the components, eg, talc—chlorite. The eadier Hterature, however, has reference to specific minerals such as kulkeite [77113-95-2] (talc—chlorite and tosudite... 

Solid disinfectants (disinfectant powders) usually consist of a disinfectant substance diluted by an inert powder. For example phenolic substances adsorbed onto kieselguhr form the basis of many disinfectant powders, while another widely used powder of respectable antiquity is hypochlorite powder. Disinfectant or antiseptic powders for use in medicine include substances such as acrifiavine, or antifungal compounds such as zinc undecenoate or salicylic acid mixed with talc. 

PNEUMOCONIOSIS A group of lung diseases of a chronic fibrotic character due to the inhalation and retention in the lungs of a variety of industrial dusts. The main diseases are asbestosis, silicosis, coalworkers pneumoconiosis and mixed-dust pneumoconiosis less common pneumoconioses are associated with talc, clay or aluminium. 

Hybrids combine plastics or composites with other materials such as metal, wood, etc. Plastics filled with talc or other powders are not taken into account in this chapter. 

The first aerosol experiments in this series utilizing quantitative techniques were performed by the writer in 1954. Two types of delivery were employed (a) powdered LSD diluted with talc, administered by means of a simple inertia device (Fig. la) (b) aqueous solutions of LSD administered intranasally by means of the nebulizer illustrated in Fig. lb. When a talc-LSD powder was administered intranasally, very severe reactions occurred rapidly. With a maximum dose of 256 meg delivered intranasally in the form of LSD-talc powder, subject J.M. had a most severe reaction, withdrawing to one part of my home in which the experiment took place and refusing to cooperate in his usual fashion. The data on Subject J.M. in this experiment are available. In order to study liquid aerosols, aqueous solutions of LSD-25 were administered intranasally to Subject J.M. The questionnaire was again used to estimate the severity of the reaction. The following technique of comparison was employed. 

Latex molding employs casts made of unglazed porcelain or plaster of paris. The molds are dusted with talc to prevent sticking. The latex compound is then poured into the mold and allowed to develop the required thickness. The mold is emptied of excess rubber and then oven dried. The mold is removed and the product is again dried in an oven. Casting is used to manufacture dolls, prosthetics, printing matrices, and relief maps. 

This continual replacement of liquid is readily visible with talc particles sprinkled on to the interface though stationary on the average (if the stirrers in phases 1 and 2 are contra-rotated at appropriate relative speeds), they make occasional sudden, apparently random, local movements, which indicate that considerable replacement of the interface is occurring by liquid impelled into the interface from the bulk. Spontaneous interfacial turbulence, associated with such processes as the transfer of acetone from solvent to water, may further increase the rate of transfer by a factor of two or three times (44, 48, 51). Other systems (48), such as benzoic acid transferring (in either direction) between water and toluene, give transfer rates only about 50% of those calculated by Eq. (26), suggesting either that this equation is not valid or that there is an interfacial resistance. This point is discussed in detail below. 

The quantity Cr correlates the effects of monolayers, both spread and adsorbed, on K, as in Fig. 11. As one may show quantitatively with talc particles, the eddy velocity at the interface is greatly reduced by the mono-layer. The latter restrains fresh liquid from being swept along the surface, i.e., there is less clearing of the old surface. If now All is the surface pressure resisting the eddy due to its partly clearing an area (Fig. 12) in... 

Iran. The grain is taken orally for intestinal inflammation and administered rectally for diarrhea. The grain flour is used externally to reduce topical inflammation, to remove rash and erythema, and to treat genital irritation in children resulting from contact with urine, and it is mixed with talc powder to prevent dryness of the skin . ... 

Dampproofing admixtures are water-repelling materials such as wax emulsions, soaps and fatty acids which react with cement hydrates [84, 85]. The most widely used water-repelling materials are the calcium or ammonium salts of fatty acids such as stearates. Proprietary products are available both as dry powders and liquids. Usually, a stearate soap is blended with talc or fine silica sand and used at the prescribed dosage per weight or bag of cement. In commercial liquid preparations, the fatty-acid salt (soap) content is usually 20% or less, the balance of the solid material is made up of lime or CaCl2. Some proprietary admixtures combine two or more admixtures, e. 

The surface of the subsolution was cleaned by first dusting it with Talc powder and then sweeping the surface by moving a Teflon slide from one side of the trough to the other. The Talc powder along with the impurities (if any) were then removed using... 

In the magnesian system, 7 8 chlorite can coexist with talc, magnesian trioctahedral and dioctahedral montmorillonite, boehmite and brucite. A 14 8 chlorite can coexist with magnesian montmorillonite, talc, quartz, kaolinite, boehmite and brucite. It is important to note that 7 8 aluminous chlorites do not stably coexist with quartz or a free silica phase. 

Polymer alloys composed of a poly(carbonate) (PC) resin and ABS or HIPS with talc as an inorganic filler have been used for housings or parts for office automation instruments and electrical or electronics instruments. 

Rather surprisingly, lubrication of the dumb-bell ends with talc sometimes improves gripping, presumably by permitting just enough slip to equalise the gripping pressure. 

It is often adulterated with cochineal exhausted of its colouring matter and then dried, or moistened with solutions of dyeing extracts (especially red wood) and is frequently mixed with talc, gypsum, or heavy spar. It is sometimes mixed also with leaden fragments or filings. The tests to be made are as follows ... 

The mercuric chloride is generally ball-milled with talc as an inert material, and then tetraethyllead is slowly added. Usually, the commercial product contains approximately 2% ethylmercuric chloride. The dilute product, as manufactured, is sold as a seed disinfectant. DuPont is the leading manufacturer. 

Reference has frequently been made to the solid and liquid states of the films. The solidity may be detected, if present, by dusting the surface with talc or other light powder, and blowing gently if the film is solid, the powder does not move appreciably. The solidity or otherwise of the films depends on the adhesive forces between both heads and chains. At about 16 carbons in the chain the alcohols are liquid and the acids solid, although the compression curve is practically the same and both appear to give the close-packed chain type of structure.1 When the chains are over i Adam, Proc. Roy. Soc. A, 101, 465 (1922). 

Williams, R. 0.3rd, and McGinity, J. W. (1989), Compaction properties of microcrystalline cellulose and sodium sulfathiazole in combination with talc or magnesium stearate, /. Pharm. Sci., 78(12), 1025-1034. 

The neovascular lesions of talc retinopathy are thought to be associated with peripheral arteriolar nonperfusion, which leads to retinal ischemia and secondary neovascularization. Such a pathogenesis is quite similar to that seen in sickle cell retinopathy and is confirmed by the predominantly supertemporal location of the neovascular proliferation. Macular fibrosis with significant visual loss has also been associated with talc retinopathy. 

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