Radium ignition

Poole has ignited Nitrogen Iodide by a single a-particle from a radium source (Refs 5 14)... 

Ionization is one of the later steps of combustion and is not the essential first step. The presence of ions formed by / rays from radium bromide makes no difference in the ignition temperatures of fuels.17 18 The primary step in combustion is the combination of oxygen molecules with fuel molecules, but as the temperature at which this combination occurs increases and the energy level of the molecules becomes greater, ionization occurs as a late stage of the process.111 The conclusion has been that ionization in gaseous explosions is mainly a thermal process and that the action of knock inducers and suppressors on combustion phenomena cannot be adequately explained on the basis of ionization effects. 

For the equilibrium between barium chromate and dichromate, vide supra, chromic acid. I. Meschtschersky found that a litre of water dissolved 4-3 mgrms. at 100°. C. R. Fresenius said that at 0°, a litre of water dissolves 1-19 mgrms. The salt is less soluble after it has been ignited. E. Schweizer said that in that state a litre of water dissolves 0-62 mgrm. L. M. Henderson and F. C. Kracek pointed out that the solubilities of the alkaline earth chromates decrease as the at. wt. of the alkaline earth metal. Thus, at 15°, the solubilities of the anhydrous calcium, strontium and barium chromates are of the order 25,1-2, and 0-0033 grms. per litre respectively. The solubility of ladiom chromate seems to follow the rifle, and a separation of radium and barium can be effected by fractional precipitation as chromates. The partition factor for acidic soln. is about 15-5. 

Entrepreneurs wasted no time in finding other commercial applications for tadium. Mixed with zinc sulphide, it produced a phosphorescent substance that was used to make luminous watch faces and aircraft instrumentation. Since radium dissipated stadc chai in surrounding air, it also reduced sparks, which made it useful in factories where flammable vapours could be ignited. Public f ination with the new wonder substance created a market for commercial applications of more dubious utility. Radium paint was used to create glow-in-the-daik slipper buttons, roulette wheels, and fish bait, and farmers were sold radioactive manures that had waste products fiom radium refineries mixed into them. 

Eldorado made a deal with U.S. Radium to market some of that firm s products in the Commonwealth. One of these was Undark, a radium-based luminous compound. The arrangement also encompassed compounds used in the manufacture of television and cathode-ray tubes. The biggest seller amor these products was the lonotron, a radioactive anti-static device that used the ability of alpha radiation to ionize air to prevent formation of static electricity. It was employed in industries where flammable vapours or materials could be ignited by sparks from static electricity. Textile and paper mills were major customers, but the lonotron helped in the operation of coating and packaging equipment as well. It enabled manufacturers to increase the speed of their machines while reducing the risk of fire. 

---