Chemical composition and properties

Impurities. The chemical composition and properties of lime and limestone depend on the nature of the impurities and the degree of contamination of the original stone. The contaminating materials either were deposited simultaneously with the CaCO or entered during some later stage (6). 

The structure theory of inorganic chemistry may be said to have been bom only fifty years ago, when Werner, Nobel Laureate in Chemistry in 1913, found that the chemical composition and properties of complex inorganic substances could be explained by assuming that metal atoms often coordinate about themselves a number of atoms different from their valence, usually four atoms at the comers either of a tetrahedron or of a square coplanar with the central atom, or six atoms at the comers of an octahedron. His ideas about the geometry of inorganic complexes were completely verified twenty years later, through the application of the technique of x-ray diffraction. 

The caramelization process can be conducted in open or closed vessels. The mixture obtained is cooled and filtered, and then the pH and specific gravity are adjusted by the addition of acids, alkalis, or water. The chemical composition and properties of caramel colors depend on reactants used and technical conditions such as time, temperature, moisture content, and pressure. During the caramelization... 

Details of the chemical composition and properties of the wide range of plastics used as engineering material can be found in the books by Butt and Wright (1980) and Evans (1974). 

The droplet size distribution produced by vaporization-condensation technique is strongly dependent on the chemical composition and properties of the liquid. If well controlled on a small scale, vaporization-condensation technique can produce moderately mono-disperse sprays with geometric standard deviations ranging from about 1.2 to 1.8.[88]... 

Pesticides of this category (Fig. 10, Table 3) do not ionize significantly in aqueous systems and vary widely in their chemical composition and properties (i.e., water solubility, polarity, molecular volume, and tendency to volatilization). 

The Langmuir-Blodgett method has been used to prepare hybrid films of an anionic Ru(ll) cyanide polypyridyl complex with LDHs [170]. An LDH film was formed on mica owing to the interaction between LDHs particles and the Ru(ll) cyanide polypyridyl complex that was pre-dispersed on the surface of mica. Water-in-oU emulsions composed of octane, water and sodium dodecyl sulfate (SDS) have been used to synthesize Mg/Al LDHs with carbonate as the interlayer anion [171] by constant pH or variable pH methods. A floccule or fiber-like LDH material that possesses similar chemical composition and properties to that synthesized using a conventional variable pH method was obtained. The resulting LDH shows high surface area and a narrow distribution of mesopores. 

Table 4.13 Chemical composition and properties of a triplebase propellant.

Chemical Composition and Properties of Fuels for Jet Propulsion , Pergamon Press, NY(1962) 7) ASTM Standards for Ash from Petroleum Pro-... 

Studies of the formation, chemical composition, and properties of deposits have shown that they consist of partially oxidized organic material, including more or less nitrogen, sulfur, and phosphorus. Compounds of iron, silicon, calcium, and other metals are present in small quantity, together with substantial amounts of lead oxides, sulfates, and halides from combustion of the antiknock fluid. The effects of these deposits are both physical and chemical in nature they may physically interfere with lubrication, heat transfer, gas flow, operation of valves and spark plugs chemically, they may bring about corrosion and oxidation. 

Fluorescence microspectrophotometry typically provides chemical information in three modes spectral characterization, constituent mapping in specimens, and kinetic measurements of enzyme systems or photobleaching. All three approaches assist in defining chemical composition and properties in situ and one or all may be incorporated into modem instruments. Software control of monochrometers allows precise analysis of absoiption and/or fluorescence emission characteristics in foods, and routine detailed spectral analysis of large numbers of food elements (e.g., cells, fibers, fat droplets, protein bodies, crystals, etc.) is accomplished easily. The limit to the number of applications is really only that which is imposed by the imagination - there are quite incredible numbers of reagents which are capable of selective fluorescence tagging of food components, and their application is as diverse as the variety of problems in the research laboratory. 

Chemical changes result in the formation of new substances when the composition of the original substance is changed for example, when a metal reacts with the oxygen of the air it forms a new substance called an oxide (as when iron goes rusty). Essential oils can also react with oxygen, which alters their chemical composition and properties. Other chemical reactions can be... 

Thus far, we have considered the varying chemical compositions and properties of glasses. In this last section, we will examine an important architecture - glass fibers, of paramount importance in our society. The synthesis of glass fibers dates back to... 

The principal output products are gaseous and liquid hydrocarbon fractions that are remarkably similar to the refinery cracking products. Their chemical composition and properties strongly depend on the input feed composition, (i.e. proportion of polyethylene, polypropylene and polystyrene in the feedstock) and they can also be unstable due to their high reactive olefins content (especially from polyethylene and polystyrene cracking). 

There is considerable interest in the chemical composition and properties of citrus oils and essences as well as the role they play in food and nonfood industries. Citrus peel oils and essences possess a pleasant aroma, with oxygenated compounds being the major constituents that account for their characteristic odor. Terpenes, the most abundant components in cold-pressed citms peel oil, are removed in concentrated oil production, usually by use of adsorbant and supercritical carbon dioxide, to increase the concentration of oxygenated compounds and to enhance the qualification of the oil. Meanwhile, citms seed oils are composed largely of triacylglycerols and are rich in oleic and linoleic acids. 

G Feher and MY Okamura (1978) Chemical composition and properties of reaction centers. In RK Clayton and WR Sistrom (eds) The Photosynthetic Bacteria, pp 349-386. Plenum... 

Table 4-16. Chemical compositions and properties oftriple-base propellants.

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