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Carbonate minerals subjected to high P and T conditions will decarbonate that is, the metal carbonate will decompose into a metal oxide and CO2 ... [Pg.374]

The practice is fairly simple and basically consists of obtaining an alcoholic extract from Vegetable, Animal or Mineral subjects, and igniting the alcohol under a cooling dome or similar cooling setup that will capture the hot vapors that arise and then condensing them. [Pg.97]

All minerals subjected to the shear strength measurement have been compressed for half an hour at varying pressures to obtain a stable cake height. This compression time (half an hour) has been chosen according to the typical compression kinetics of Ti02 as an example given in Fig.2. As it is seen in Fig.2, the cakes have reached to a constant height in 3-5 minutes by compression at 4-20 bar and therefore to make sure 30 minutes has been taken as the compression time in each experiment. [Pg.576]

Properties Lead-gray mineral, subject to blackish tarnish, metallic luster. D 4.52-4.62, Mohs hardness 2. Soluble in concentrated boiling hydrochloric acid with evolution of hydrogen sulfide. [Pg.1179]

These effects of differential vapor pressures on isotope ratios are important for gases and liquids at near-ambient temperatures. As temperature rises, the differences for volatile materials become less and less. However, diffusion processes are also important, and these increase in importance as temperature rises, particularly in rocks and similar natural materials. Minerals can exchange oxygen with the atmosphere, or rocks can affect each other by diffusion of ions from one type into another and vice versa. Such changes can be used to interpret the temperatures to which rocks have been subjected during or after their formation. [Pg.365]

Annual Proceedings of the Safety Seminars, Dept, of Defense, Explosive Safety Board, Washington, D.C. International symposia on explosives and closely related subjects are excellent sources of information, ie, international symposia on detonation symposia on combustion symposia on chemical problems connected with the stabiUty of explosives international pyrotechnics seminars symposia on compatibiUty of plastics and other materials with explosives, propellants, and pyrotechnics, and processing of explosives, propellants, and ingredients and symposia on explosives and pyrotechnics Mineral Industy Surveys, U.S. Bureau of Mines, Pittsburgh, Pa. Periodic pubhcations dedicated primarily to explosive studies in Propellants and Explosives Journal of Ha yardous Materials, and apparent consumption of industrial explosives and blasting agents in the United States. [Pg.30]

The odor detection-threshold values of organic compounds, water, and mineral oil have been determined by different investigators (Table 2 and 3) and may vary by as much as 1000, depending on the test methods, because human senses are not invariable in their sensitivity. Human senses are subject to adaption, ie, reduced sensitivity after prolonged response to a stimulus, and habituation, ie, reduced attention to monotonous stimulation. The values give approximate magnitudes and are significant when the same techiriques for evaluation are used. Since 1952, the chemistry of odorous materials has been the subject of intense research (43). Many new compounds have been identified in natural products (37—40,42,44—50) and find use in flavors. [Pg.11]

Guar gum [9000-30-0] derived from the seed of a legume (11,16), is used as a flocculant in the filtration of mineral pulps leached with acid or cyanide for the recovery of uranium and gold (16). It is also used as a retention aid, usually in a chemically modified form (14,17). Starch and guar gum are subject to biological degradation in solution, so they are usually sold as dry powders that are dissolved immediately before use. Starch requires heating in most cases to be fully dissolved. [Pg.32]

Two main operational variables that differentiate the flotation of finely dispersed coUoids and precipitates in water treatment from the flotation of minerals is the need for quiescent pulp conditions (low turbulence) and the need for very fine bubble sizes in the former. This is accompHshed by the use of electroflotation and dissolved air flotation instead of mechanically generated bubbles which is common in mineral flotation practice. Electroflotation is a technique where fine gas bubbles (hydrogen and oxygen) are generated in the pulp by the appHcation of electricity to electrodes. These very fine bubbles are more suited to the flotation of very fine particles encountered in water treatment. Its industrial usage is not widespread. Dissolved air flotation is similar to vacuum flotation. Air-saturated slurries are subjected to vacuum for the generation of bubbles. The process finds limited appHcation in water treatment and in paper pulp effluent purification. The need to mn it batchwise renders it less versatile. [Pg.52]

The mixed valent oxide Mn.O occurs in nature as the mineral hasumannite. The stmcture of this ferromagnetic material has been the subject of much dispute. Mn.O is the most stable of the manganese oxides, and is formed when any of the other oxides or hydroxides are heated in air above 940—1000°C. The oxidation of aqueous solutions of Mn (OH)2 can also lead to the formation of Mn O. ... [Pg.507]

The H2S sulfanes are the subject of several reviews (129,133). Except for hydrogen sulfide these have no practical utiUty. Sodium tetrasulfide [12034-39-8] is available commercially as a 40 wt % aqueous solution and is used to dehair hides in taimeries, as an ore flotation agent, in the preparation of sulfur dyes (qv), and for metal sulfide finishes (see Leather Mineral recovery and processing). [Pg.137]

Vitamin D deficiency in animals may be caused by the fact that the vitamin is not available to the hvestock. Modem animal husbandry subjects animals to total confinement with htde or no exposure to sunlight. This mandates that they be given vitamin D-fortified diets. The vitamin is sensitive to oxidation, heat, light, and minerals, and significant losses may occur in the fortified feed unless the product is adequately protected. Mycotoxins in feeds also interfere with utilization of vitamin D in feeds (207—209). [Pg.137]

Waxes obtained from natural sources such as vegetables or iasects are subject to weather conditions which may severely affect the stabiUty of supply and price and, to a lesser extent, the consistency of the products. Waxes from minerals and synthetic sources are less susceptible to weather conditions, and thus have a more stable supply and price. [Pg.314]

Binders. To create needed physical strength in catalysts, materials called binders are added (51) they bond the catalyst. A common binder material is a clay mineral such as kaolinite. The clay is added to the mixture of microparticles as they are formed into the desired particle shape, for example, by extmsion. Then the support is heated to remove water and possibly burnout material and then subjected to a high temperature, possibly 1500°C, to cause vitrification of the clay this is a conversion of the clay into a glasslike form that spreads over the microparticles of the support and binds them together. [Pg.173]

A wide variety of animal species are subjected to the administration of drugs during their lifetime.The various animal species can encounter drugs and other dietary additives by different routes and this is dependent on the environment in which they are kept. Intensively reared animals tend to have considerable consistency in the components of their diets and thus are much less likely to encounter the range of naturally produced compounds that extensively produced animals encounter. The desire for less expensive dietary constituents and increased efficiency of use has induced feed manufacturers and producers to add enzyme supplements to diets of most farmed animals to reduce the negative effects of indigestible dietary carbohydrates, refactory proteins and unavailable minerals such as phosphorus. This use of dietary additives to improve nutrient utilization and environmental consequences of feeding animals intensively has been the subject of intense research activity in the last five years. " The... [Pg.90]

When a forest system is subjected to acid deposition, the foliar canopy can initially provide some neutralizing capacity. If the quantity of acid components is too high, this limited neutralizing capacity is overcome. As the acid components reach the forest floor, the soil composition determines their impact. The soil composition may have sufficient buffering capacity to neutralize the acid components. However, alteration of soil pH can result in mobilization or leaching of important minerals in the soil. In some instances, trace metals such as Ca or Mg may be removed from the soil, altering the A1 tolerance for trees. [Pg.121]

Dry aerosols, or particulate matter, differ so much from the carrying gas stream that their removal should present no major difficulties. The aerosol is different physically, chemically, and electrically. It has vastly different inertial properties than the carrying gas stream and can be subjected to an electric charge. It may be soluble in a specific liquid. With such a variety of removal mechanisms that can be applied, it is not surprising that particulate matter, such as mineral dust, can be removed by a filter, wet scrubber, or electrostatic precipitator with equally satisfactory results. [Pg.462]


See other pages where SUBJECTS mineral is mentioned: [Pg.3]    [Pg.97]    [Pg.1084]    [Pg.337]    [Pg.149]    [Pg.261]    [Pg.271]    [Pg.35]    [Pg.35]    [Pg.352]    [Pg.36]    [Pg.101]    [Pg.243]    [Pg.313]    [Pg.539]    [Pg.542]    [Pg.405]    [Pg.184]    [Pg.383]    [Pg.95]    [Pg.31]    [Pg.193]    [Pg.67]    [Pg.230]    [Pg.458]    [Pg.495]    [Pg.409]    [Pg.6]    [Pg.43]    [Pg.451]    [Pg.89]    [Pg.497]    [Pg.68]    [Pg.271]   


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