Chalking, definition

Definitions. In addition to showing varying degrees of chemical purity, limestone assumes a number of widely divergent physical forms, including marble, travertine, chalk, calcareous mad, coral, shell, ooHtes, stalagmites, and stalactites. AH these materials are essentially carbonate rocks of the same approximate chemical composition as conventional limestone (2—4). 

Chaikina. The destruction of the binder which we call chalking has been known and feared for a very long time. The definition according to ASTM D 659 is as follows ... 

Blue materials used as pigments or dyes, were the lapis lazuli (ultramarine), azurite (armenium). Both of these sometimes were called caeruleum. Indicum was indigo imported from India. Purpurissium was the name given to a pigment made from chalk colored with a purple dye, but whether from murex, indigo or woad does not seem definitely stated. 

A coarse grayish-green talc rock has been called soapstone or steatite and was formerly much used for stoves, sinks, electrical switchboards, etc, Talc finds use as a cosmetic, for lubricants and as a filler in paper manufacturing. Most tailor s chalk consists of talc. The origin of the word talc is not definitely known. 

Drift From the Chalk Point Natural Drift Brackish Water Cooling Tower Source Definition, Downwind Measurements, Transport Modeling... 

Figure 2.2 The law of definite composition. Calcium carbonate is found naturally in many forms, including marble (fop), coral bottom), chalk, and seashells. The mass percents of its component elements do not change regardless of the compound s source.

Corporal punishment has been abolished in maintained schools since August 1987, the definition of corporal punishment includes not only use of the cane but other forms of physical chastisement for example, slapping, rough handling and throwing missiles such as chalk... 

The development of isotope production at Chalk River was watched closely by Eldorado s management. Early in 1947, Errington had recommended to Bennett that Eldorado send an employee to Chalk River for several months to gain an understanding of the production of isotopes and their possible applications. It was most desirable, he noted, that a definite arrangement be made with the National Research Council at as early a date as possible. He budgeted four thousand dollars to cover preliminary... 

The procedure also serves to reveal small amounts of non-dolomitic magnesium in chalk. The magnesia content was definitely established in a limestone of the composition 0.49 % MgO, 64.02 % CaO, 1.77 % FcjOs + AlgOg, 0,23 % SiOg, 2ind 32.27 % loss on ignition. 

The momentous summary of the spent researches was definition of boundary concentration of slurry various a dust after which excess general efficiency of a dust separation decreases. Value of magnitude of boundary concentration, as it is known, is necessary for definition of the maximum extent of recireulation of an irrigating liquid. As appears from presented in Figures 4.3-4.6 sehedules, dependenee ofgeneraleffieiency of a dust separation on concentration of slurry, aeeordingly, for a powder of talc, a chalk and white blaek is available possibility of definition of such concentration. 

A soil profile is a section taken vertically through the soil. In some cases this may consist only of a shallow surface soil of 10-15 cm on top of rock such as chalk or limestone. In deeper well-developed soils there are usually three or more definite layers (or horizons) which vary in colour, texture and stmcture (Fig. 3.1). The soil profile can be examined by digging a pit or by taking ont cores of soil from various depths using a soil auger. A careful examination of the layers can be useful for assessing soil texture, stmcture and eompaction as well as the soil cropping potential. The colour of the soil in the various horizons will indicate whether the soil is well or poorly drained. 

According to the ASTMD658 definition, chalking is the phenomenon manifested in paint films by the presence of loose removable powder, evolved from the film itself, at or just beneath the surface. 

Definition. It is the faUure of a coating by the formation of a powdery layer on a coating surface. As the powder is white, the failure is referred to as chalking (Fig. 7.11). 

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