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Σελίδα 194 - Record the temperature of the oil sample at start. (c) When the temperature of the oil reaches 9° F. (5° C.) below the probable flash point of the oil, turn the knob on the cover so as to introduce the test flame into the cup, and turn it promptly back again. Do not let it snap back. The time consumed in turning the knob down and back should be about one full second, or the time required to pronounce distinctly the words
Σελίδα 249 - BaSO4 is soluble in acids and even in pure water, and the solubility limit is reached almost immediately on contact with the solvent. Hence, in the event of using reagents of very superior quality or of exercising more than ordinary precautions, there may be no apparent "blank," because the solubility limit of the solution for BaSC>4 has not been reached or at any rate not exceeded.
Σελίδα 242 - Glass capsules with ground-glass caps may also be used. They should be as shallow as possible, consistent with convenient handling. METHOD.
Σελίδα 213 - ... or more shall be collected. The gross sample should contain the same proportion of lump coal, fine coal, and impurities as is contained in the coal sampled. When coal is extremely lumpy it is best to break a proportional amount of the lumps before taking the various increments of a sample.
Σελίδα 217 - After the gross sample has been reduced by the above method . to approximately 250 lb., further reduction in quantity . ' shall be by the quartering method. Before each quartering, the sample shall be crushed to the fineness oreQuartering Quantities of 125 to 250 lb.
Σελίδα 214 - Ib., and care shall be observed before each reduction in quantity that the sample has been crushed to the fineness prescribed in Table I. The crushed coal shall be shoveled into a conical pile (Figs. 2...
Σελίδα 214 - V) by depositing each shovelful of coal on top of the preceding one, and then formed into a long pile in the following manner : The sampler shall take a shovelful of coal from the conical pile and spread it out in a straight line (Figs.
Σελίδα 113 - The so-called wet bulb is thoroughly saturated with water by dipping it into a small cup or wide-mouthed bottle. The thermometers are then whirled rapidly for fifteen or twenty seconds ; stopped and quickly read, the wet bulb first. This reading is kept in mind, the psychrometer immediately whirled again and a second reading taken. This is repeated three or four times, or more if necessary, until at least two successive readings of the wet bulb are found to agree very closely, thereby showing that...
Σελίδα 218 - No. 4 sieve, under such conditions as shall prevent loss or the accidental admixture of foreign matter. The crushing shall be done mechanically with a jaw crusher, or by hand on a chilled iron or hard steel plate by impact of a chilled iron or hard steel tamping bar, hammer or sledge, avoiding all rubbing action, otherwise the ash content of the sample will be materially increased by the addition of iron from the crushing apparatus, even though hardened steel or chilled iron is used. After all the...