Oxygen high pressure, control

This equation indicates that the oxygen partial pressure controls the vaporization of the silica. For example, if the PO2 is 10 atm (a reasonable value in a reducing atmosphere of H2 or CO), then the Psio will be -3 x 10 , which is quite high, so the Si02 evaporates. Hence SiOi would not be a good refractory in a dry reducing atmosphere. The effect can be minimized by adding a small amoimt of H2O if H2 is present. 

Well-documented studies have been performed to compare the fatigue behavior in air and under vacuum at low or moderate temperature of copper (Wang et al., 1984 Bayerlein and Mughrabi, 1992) and austenitic stainless steels (Gerland et al., 1988 Mendez et al., 1993). As an example. Fig. 5-12 shows the marked effect of an air environment at room temperature, even for a corrosion-resistant alloy. High cumulative plastic strain amplitudes can be reached under vacuum. The oxygen partial pressure controls the nature of the surface oxide and localization of the crack initiation process in persistent slip bands formed by cyclic straining. 

DEHA breaks down at high pressure. Its survival pressure is probably not in excess of 1,250 psig, but because of its high volatility and rapid reaction rate, it generally provides complete boiler cycle oxygen-control coverage. Some limited ammonia is also generated, and this may be useful for carbon dioxide neutralization. 

Reactor vessels range in volume from 1.2 to 2.5 liters. The size used may be dependent on the pressure application requirements. A high-pressure reactor can run up to about 60 bar. Porting is provided on the reactor vessel for auxiliary probes (e.g, oxygen sensors, pH measurement, and on-line analysis). These probes may be inserted directly into the reactor contents. Porting is also available for the controlled addition of gas, liquid, or solid materials. 

The Varian E-3 was also used for the study of radical cation formation as a function of oxygen pressure in the dark. Oxygen was supplied by a high pressure cylinder, and the lower pressures were controlled by a manometer assembly. The initial studies were per-... 

Study of CrOj+a—control of high pressure oxygen gas by thermal decomposition of oxides... 

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