Sensitizers of oxygen

A consequence of the extreme sensitivity of oxygen pressure to stoichiometry for small values of x in Pu02-X is that the total pressures change by a factor of about 103 in going from Pu0j.9g to PuOj go at 4000 K. In contrast, the corresponding factor for the U/0 system is approximately 2. 

The comparison among runs (A-l to A-4) shows the sensitivity of oxygen addition to the graft efficiency. The best results in this heterogeneous reaction system are realized when the O2 is introduced slowly so that O B at any time. 

Many other modifications to acrylic adhesives are useful. Improved heat resistance of acrylic adhesives can be achieved by incorporating small amounts of epoxy resin into the formulations,77 or by including cyanate esters and organometallic compounds to provide an additional crosslinking mechanism.78 Lower sensitivity of oxygen can be achieved by... 

In this way the sensitivity of oxygen consumption measurements is increased, that is, 1 mole of oxidized substrate corresponds to 1 mole of oxygen taken up. When catalase is added in absence of a hydrogen donor, 1 mole of the oxidized substrate corresponds to 2 mole of oxygen (Table IV). 

In barrier packaging, it is generally accepted that orientation of the barrier resin reduces its gas permeability. Most of the published data, however, corresponds to low barrier resins. No supporting data exists yet for either high or intermediate barrier resins. To fill that void, the orientability and the sensitivity of oxygen permeability to orientation for six competitive oxygen barrier resins were evaluated. The barrier resins evaluated in this investigation include an experimental... 

The studies of Taylor and coworkers into water-rock interacdon have wide applicability in many fields of geochemistry. In general terms the sensitivity of oxygen isotopes to hydrothermal solutions means that they are an excellent tool for detecting hydrothermal alteration in othe ise fresh rocks (see for example Rautenschlein et al., 1985). More specifically, the origin of the water may be identified and its volume relative to the country rock quantified. Some examples are briefly reviewed. 

For further improvement of fuel cell performance, first of all obvious problems mentioned in the chapters of this book need to be solved, such as raising the activity of catalysts for methanol oxidation, lowering the sensitivity of oxygen-electrode catalysts toward methanol, and building new improved membranes. In addition, a number of fundamental problems need to be solved in the field of electrocatalysis ... 

The development of neutron diffraction by C G Shull and coworkers [30] led to the detennination of the existence, previously only a hypothesis, of antiferromagnetism and ferrimagnetism. More recently neutron diffraction, because of its sensitivity to light elements in the presence of heavy ones, played a cmcial role in demonstrating the importance of oxygen content m high-temperature superconductors. 

Note 2. In view of the sensitivity of cumulenic ethers to oxygen the work up was carried out under nitrogen with water that had been saturated with ni trogen. 

Note 2. The allenic ether is extremely sensitive towards oxygen. All operations during the work-up must be carried out under nitrogen. After termination of the distillation nitrogen should be admitted to the distillation apparatus. Too strong heating during the distillation involves the risk of an explosion. 

From the perspective of laboratory practice, the sensitivity of many indoles to acids, oxygen and light prescribes the use of an inert atmosphere for most reactions involving indoles and the avoidance of storage with exposure to light. This sensitivity is greatly attenuated by electron-withdrawing (EW) substituents. 

Usually, organoboranes are sensitive to oxygen. Simple trialkylboranes are spontaneously flammable in contact with air. Nevertheless, under carefully controlled conditions the reaction of organoboranes with oxygen can be used for the preparation of alcohols or alkyl hydroperoxides (228,229). Aldehydes are produced by oxidation of primary alkylboranes with pyridinium chi orochrom ate (188). Chromic acid at pH < 3 transforms secondary alkyl and cycloalkylboranes into ketones pyridinium chi orochrom ate can also be used (230,231). A convenient procedure for the direct conversion of terminal alkenes into carboxyUc acids employs hydroboration with dibromoborane—dimethyl sulfide and oxidation of the intermediate alkyldibromoborane with chromium trioxide in 90% aqueous acetic acid (232,233). 

B. R. Dunbobbin and co-workers, "Oxygen Compatibihty of High-Surface-Area Materials," in Flammabilif and Sensitivity of Materials in Oyygen-EnrichedAtmospheres, Vol. 5, ASTM STP 1111, American Society for Testing and Materials, Philadelphia, Pa., 1991. 

The product is considered nonhazardous for international transport purposes. However, it is an oxidizing agent sensitive to decomposition by water, direct sources of heat, catalysts, etc. Decomposition is accompanied by the Hberation of oxygen and heat which can support combustion and cause pressure bursts in confined spaces. Decomposition in the presence of organic material is rapid and highly exothermic. 

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