Effect oxygen

Photoinitiation. Since photolysis of polysdanes generates sdyl radicals, which can add to carbon—carbon double bonds, these polymers have been used for the free-radical polymerization of unsaturated organic monomers (135,136). Though about one-tenth as efficient as other organic photoinitiators, polysdanes are nevertheless quite insensitive to oxygen effects, which somewhat compensates for their lower efficiency. 

The reactive species might be V(OH)2l, produced in a similar manner to the analogous species in the oxidation of bromide ion, which could undergo one-equivalent breakdown to V(IV) and atomic iodine. Ramsey et al postulate transfer of OH to iodide ion, but the intermediacy of-12 is referred to in a later study of the oxygen effect to account for the relation ... 

A few details have been reported on the slow reductions of 8303 by As(ni) and T1(I) . In the anaerobic reductions by As(III) the reaction is first-order in 820 and although As(III) certainly catalyses decomposition, the dependence of the rate on [As(III)] is small. Aeration leaves the rate of spontaneous decomposition of 820g unaffected, but the As(III)-catalysed route is accelerated by a factor of ten, the kinetic law remaining unchanged. The oxygen effect is interpreted in terms of the chain reaction... 

Furthermore, reaction (27) of Westheimer s scheme seems to be rather arbitrary. If chromium(II) were really formed, the rate of oxidation of alcohol would certainly be influenced by oxygen. However, careful experiments show that there is no oxygen effect at all . 

During the induced reduction of chlorate a considerable oxygen effect was observed. The air oxidation of arsenic(ril) is also an induced reaction, the extent of which decreases with increasing acid concentration and is increased by decreasing the rate of primary reaction. The induced oxidation caused by air also can be observed during the osmium tetroxide-catalyzed chlorate-arsenic(III) reaction. 

The physical disability is tiring but manageable. I know how to get strapped into the wheelchair. I know where the curb cuts are and how to maneuver the chair. I can cope with the industrial respirator. If I have to wear my army helmet I can do that, too, although I hate to in public places because who wants to look like a geek But sometimes that s what I have to do. I know how to use oxygen effectively. 

Some preliminary ENDOR investigations of the fascinating cooperative oxygenation effect in hemoglobin have been reported by Feher et al.243). Since magnetic resonance... 

Oxygen Effect. To avoid inhibitory effect of oxygen is very important if a large scale practical application is aimed at. 

G. B. Strambini, Singular oxygen effects on the room-temperature phosphorescence of alcohol dehydrogenase from horse liver, Biophys. J. 43, 127-130 (1983). 

No phosphorescence could be observed (thus < 10 8) from 7 in acidified 2-propanol or ethylene glycol/water (1 2) solutions upon 313 nm exitation at 77 K 78). This is surprising in view of the oxygen effect cited above. 

The final 0-D equation presented here stems from incorporating the gas-pressure dependences directly instead of through a limiting current density, which normally only considers oxygen effects. This equation was proposed by Newmanfor phosphoric-acid fuel cells and predates the above polymer—electrolyte fuel-cell expressions. It has the form... 

The width of the EPR absorption line is also dependent on the temperature of formation of the carbon and depends somewhat on whether the sample is carbonized in air or in vacuo as illustrated in Fig. 34. The difference in width obtained between air and in vacuo carbonization is a manifestation of the oxygen effect. If oxygen is added to coals and sugars heated above 500° or activated charcoals heated to a temperature above 100° a pronounced increase in width of the EPR signal occurs. The total, integrated intensity of the EPR absorption, however, does not change greatly. Thus, in this effect the total number of radicals remains approxi-... 

Fig. 35. Oscilloscope tracings of oxygen effects. Top decay of EPR signal of coals, charred sugars and activated carbons heated above 100° with increase in oxygen pressure. Bottom decay of EPR signal in activated carbons with increase in oxygen pressure (181).

K. Simino and I. Yonenaga, Oxygen Effect on Mechanical Properties W. Bergholz, Grown-in and Process-Induced Effects... 

H. Tsuya, Oxygen Effect on Electronic Device Performance... 

Historically, the oxygen effect was the main rationale for introducing fast neutrons in radiotherapy. Three sets of data support this rationale ... 

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