Burnt

Figure 2.8 shows the essential features of a refinery catalytic cracker. This particular reaction is accompanied hy the deposition of carhon on the surface of the catalyst. The fiuidized-hed reactor allows the catalyst to he withdrawn continuously and circulated to a fiuidized regenerator, where the carhon is burnt ofi" in an air stream, allowing regenerated catalyst to he returned to the cracker. 

The solid particles are fluidized by air and fuel, which are fed to the bed and burnt to produce the high temperatures necessary for the reaction. 

Depending on the mix of waste being burnt, the incinerator may or may not require auxiliary firing from fuel oil or natural gas. 

Increase energy efficiency of the process. Increasing the energy efficiency decreases the fuel burnt and hence decreases SO, emissions at the source. Again, the emissions should be viewed on a global basis. 

One advantage of anaerobic reactions is that the methane produced can be a useful source of energy. This can be fed to steam boilers or burnt in a heat engine to produce power. 

With most non-isothemial calorimeters, it is necessary to relate the temperature rise to the quantity of energy released in the process by determining the calorimeter constant, which is the amount of energy required to increase the temperature of the calorimeter by one degree. This value can be detemiined by electrical calibration using a resistance heater or by measurements on well-defined reference materials [1], For example, in bomb calorimetry, the calorimeter constant is often detemiined from the temperature rise that occurs when a known mass of a highly pure standard sample of, for example, benzoic acid is burnt in oxygen. 

Selenium dioxide is a volatile solid obtained when selenium is burnt in air or oxygen. It is very soluble in water, forming a solution of... 

Tellurium dioxide, Te02, is a white non-volatile solid obtained when tellurium is burnt in air. It is only slightly soluble in water but dissolves in alkalis to form salts. 

This reaction is also used on a large scale, to obtain iodine from seaweed. The ash from burnt seaweed ( kelp ) is extracted with water, concentrated, and the salts other than iodides (sulphates and chlorides) crystallise out. The more soluble iodides remain and the liquor is mixed with sulphuric acid and manganese dioxide added the evolved iodine distils off and is condensed. 

Cane sugar.—Melts, darkens, then chars, and finally burns, with a marked odour of burnt sugar. Typical of the changes given by mono- and di-saccharides. 

Tartaric acid and tartrates also swell up, blacken and give an odour resembling burnt sugar. Citrates and lactates also char, and give off odours resembling burnt sugar. 

After some experience, an able student will find that it is frequently unnecessary to carry out all the Tests A—L. If, for example, the substance is found to contain only carbon and hydrogen, and chars on ignition giving a smell of burnt sugar, then confirmatory tests (given in... 

The second indication is a faint smoke-like cloudiness in the zone of the tube which is being heated by the Bunsen this is readily visible as the interior of the tube is normally quite clear and bright. This is a later stage of development of the flash-back than the rise of pressure, already mentioned, and should be counteracted by moving the Bunsen immediately to the point of the combustion tube where heating was commenced. In either case the Bunsen should then be moved slowly forwards as before. A flash-back is attended by the deposition of carbon particles, carried back by the explosion wave, on the cold walls of the tube. Care should be taken that these are completely burnt off as the Bunsen is slowly moved forward again. 

These included Scheele, Cavendish, Priestley, and others. They called it burnt or dephlogisticated air," which meant air without oxygen. 

Fig. 4.23 Adsorption isotherms of butane vapour at difTerent temperatures on a sample of carbon (prepared by heating a mixture of coke and pitch at 600°C), burnt off by 0.27%.

Values of the uptake at saturation, of butane, carbon dioxide and nitrogen, by a sample of carbon, expressed as a volume of liquid v,. The carbon had been "burnt off" to different extents by heating in oxygen at 500°C on a sorption... 

Maintenance of conditions ia the culture environment that keep stress to a minimum is one of the best methods of a voiding diseases. Vacciaes have beea developed agaiast several diseases and more are under development. Selective breeding of animals with disease resistance has met with only limited success. Good sanitation and disiafection of contaminated faciUties are important avoidance and control measure. Some disiafectants are Hsted ia Table 6. Poad soils can be sterilized with burnt lime (CaO), hydrated lime [Ca(OH)2], or chlorine compounds (12). 

A. G. Sharpe, Inorganic Chemist, 3rd ed., Longman Scientific and Technical, Burnt Hill, Essex, U.K., (co-pubhshed in U.S. byjohn Wiley Sons, Inc. New York), 1992, p. 211. 

Current research aims at high efficiency PHB materials with both the high speed recording and high recording density that are required for future memory appHcations. To achieve this aim, donor—acceptor electron transfer (DA-ET) as the hole formation reaction is adopted (177). Novel PHB materials have been developed in which spectral holes can be burnt on sub- or nanosecond time scales in some D-A combinations (178). The type of hole formation can be controlled and changed between the one-photon type and the photon-gated two-photon type (179). 

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