Oxygen explosion technique

In the oxygen explosion technique (Chap. 13.4), an electron pulse is delivered to a thin layer of anoxic cells to which O2 is admitted in a flash either before or after the pulse (Michael et al. 1973,1979). 

It has been shown above that there is a marked effect of the charge of the thiol and its efficiency to protect against OH attack but also to repair DNA damage (for thiol binding to DNA see Smoluk et al. 1986). An extension to GSH-deficient cells in combination with the oxygen explosion technique allowed to determine the rate constants of various thiols with radiation-induced DNA damage (Table 12.21 Prise et al. 1995). 

Explosion prevention by inerting has several advantages over explosion protection techniques, such as explosion venting. For example, with successful inerting, fires or business interruptions cannot occur. Nevertheless, beware of the potential of asphyxiation with inerting proper vessel entry procedures must be implemented and occasionally it may be prudent to monitor for oxygen in workplaces. 

Calorific Values of Explosives, Calorific value is defined by Weissberger (Ref 3) as the heat evolved when the substance is exploded in the absence of oxygen except for what it contains itself . This quantity is practically the same as the heat evolved when the substance is exploded under normal operating conditions (such as in bore holes or in shells). Experimental techniques differ somewhat from chose employed in ordinary combustion calorimetry. The bombs employed in calorific value techniques are smaller in capacity and possess very thick walls to withstand high pressures. For example the bomb described in Ref 2 is of 124cc capacity. It was developed at Woolwich Arsenal and modified by Taylor et al. 

Activation of aluminum in a cavity, ball or vibration mill. This activation technique should be used in nitrogen and in 5% solution of triethylaluminum in n-heptane, because aluminum suspension is easily transported through pipes and activated aluminum is protected from oxidation (with oxygen in air) during transportation and storage. Besides, wet grinding is less explosive than dry. Aluminum powder should be activated in the mill for 20-30 hours. The aluminum ground in a vibration mill is the most active. 

After evacuation, standard vacuum techniques are used to measure and condense equimolar amounts (20 mmoles each) of carbonyl fluoride and oxygen difluoride into the cylinder. The cylinder should be equipped with an explosion rupture assembly and should be in a shielded location before it is allowed to warm up. The valve is then closed, and the cylinder and its contents are allowed to warm to room temperature and remain at that temperature for 5 days. After this time, the cylinder contents are passed through a trap kept at approximately — 140°C. (melting Skelly-Solve F or methylcyclopentane). 

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