Smoke pellets

Smoke pellets are produced in a range of sizes and are commonly used tor the resting of household flues and chimneys. The pellet is ignited and will burn for about 10 seconds producing a dense white smoke. Because this is a combustion process there are obvious restrictions on its use (nonflammable atmo spheres, nonflammable surfaces, etc.). In addition the smoke is buoyant because of the heat generated. The smoke can also be an irritant and/or toxic. The production of smoke cannot be controlled, but pellets are inexpensive, easy to use, and readily available, and the smoke is produced in sufficient quantities to make them useful in the evaluation, for example, of fume cupboards and Ixroths. 

Steel mills Blast furnaces charging, pouring CO, fumes, smoke, particulates (dust) Good maintenance, seal leaks use of higher ratio of pelletized or sintered ore CO burned in waste-heat boilers, stoves, or coke ovens cyclone, scrubber, and baghouse... 

TTie ability of the ventilation system to protect the worker efficiently can readily be determined by personal samples. The PIMEX method (see Chapter 12) can be used to determine the worker s exposure during various work phases. The capture efficiency as well as the supply air fraction can be measured using tracer gas techniques. Simple evaluation is carried out visually with smoke tube or pellet tests. Daily system evaluation is recommended using airflow or static pressure measurements at appropriate parts of the system. The air velocities, turbulence intensities, air temperature, mean radiant temperature, and air humidity should also be measured to provide an assessment ol thermal comfort. 

A Del Electronics, Model ESP-100A, electrostatic precipitator was used for sample collection. Cigarette smoke particles were found to give approx the same particle distribution pattern on the collection filter paper as the gunshot residue, and since the smoke stains the paper, this provided a v rapid technique for optimizing operation conditions. With a flow rate of 15cfm and a corona current of 125 uA, the residue collects primarily on a narrow band across the sample paper. Samples were collected on Whatman No 1541 filter paper which lined the inside of the sample collection tube. The presence of this paper allowed air to flow only thru the center of the tube, so particle collection was made upon the filter paper exclusively. The filter paper samples were pelletized prior to neutron activation analysis... 

Hexachloroethane is a colorless solid that gradually evaporates when it is exposed to air. This compound is also called perchloroethane, carbon hexachloride, and HCE. It is sold under the trade names Avlothane, Distokal, Distopan, and Distopin. In the United States, about half of the hexachloroethane is used by the military for smoke-producing devices. It is also sold as degassing pellets that are used to remove the air bubbles in melted aluminum. Hexachloroethane may be present as an ingredient in some fungicides, insecticides, lubricants, plastics, and cellulose. At one time, hexachloroethane was prescribed for deworming animals. 

Arterial endothelial injury. Environmental smoke, administered to ovariectomized rats treated with subcutaneous placebo or 17 p-estradiol pellets for 6 weeks, produced a more than fourfold increase of carotid artery low-density lipoprotein (LDL) accumulation compared with filtered air exposure. The effect was largely mediated by increased permeability. No protective effect of estradiol was observed. Acute smoke exposure of a buffer solution containing LDL produced a more than sixfold increase in the highly reactive carbonyl glyoxal. Perfusion of this solution through carotid arteries produced 105% increase in permeability. Perfusion of glyoxal alone produced a 50% increase in carotid artery permeability ... 

Tetracene exists as colorless or pale yel ndls mp decomp ca 142° and explodes at 160° in 5 secs (vs 190° for MF) explodes in a flame w/o much noise but producing much bk smoke apparent a only 0.45, but yields a pellet of d 1.05 when compressed at 3000 psi. It is practically insol in w, ale, eth, acet, benz, CC14 and ethylene dichloride sol in dilute nitric acid decompd by boiling w with formation of 2N2 per mole can easily be dead-pressed (Ref 10)... 

Sodium azide pellets arc rather inert and of little practical value that we could discover. When thrown into a stove, they eventually cook off with a burst of smoke and heat. They won t go off from concussion, nor will they perform meaningful work by themselves or when mixed with Bullscye, ammonium nitrate, or black powder. 

PROJECTION — It is to be noticed that in the operation of Projection, all the Metal upon which the Powder is projected does not transform into Gold or Silver unless it has been well purified before fusion. There is an exception in the case of Mercury because it has naturally a smaller proportion of impure and heterogeneous matters, and possesses also much closer analogy with gold. To make projection upon Mercury, it is sufficient to warm it slightly, and the powder must be projected before it begins to give off smoke. The powder is wrapped in a little wax, and the pellet thus formed is cast upon the metal in fusion. The crucible is covered over, and the powder is left to act for the space of a quarter of an hour or thereabouts. The Matter is then allowed to get cold, and is then taken out of the vessel. If cracked or broken, it must be projected upon a small quantity of the same metal in fusion, for it is a proof that too much powder has been used. 

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