Oxygen production 432 Subject

Elastomers function as a barrier to either moisture or atmospheric gases (oxygen, nitrogen, and argon). This property is important in maintaining product integrity for lyophilized or liquid products subject to decomposition by water vapor or oxygen. 

In order to model the oxygenation of vitamin K in its hydroquinone form, a naph-thohydroquinone derivative with a 1-hydroxy group and 4-ethyl ether was prepared and its alkoxide subjected to oxidation with molecular oxygen. Products consistent with two possible mechanisms were isolated, the epoxy-quinone which must derive from a peroxy anion intermediate at the 4-position, and a 2-hydroxy product which... 

Oxygen, when subjected to increase of pressure, does not strictly obey Boyle s Law. At first the gas is slightly more compressible than the law demands, owing to the attraction between the gaseous molecules. Above 300 atmospheres, however, the product PY increases steadily as the influence of the dimensions of the molecules themselves begins to make itself felt. The gas thus becomes increasingly less compressible than the law requires. This is well shown by the numerical data given in the table on p. 194. 

As outlined in Scheme 5, tertiary cyclopropanol salts are also subject to the oxyanion-accelerated VCP rearrangement. In this sequence the requisite vinylcyclopropanol salts are conveniently prepared from readily available 1,1-dibromocyclopropanes by sequential halogen-metal exchanges, followed first by alkylation, and then by oxygenation. Products resulting from alternative 1,5-hydrogen shift (retro-ene) pathways were not detected in these reactions. 

I have reviewed the scientific literature of the past 176 years on hydrogen peroxide hundreds of articles on such subjects as "Catalysis of single oxygen production in the reaction of hydrogen peroxide and hypochlorous acid by diazabicyclo octane."... 

This paper presents an availability analysis of one type of oxygen production cycle centering around separation of oxygen and nitrogen in a fractionating tower. The plant is driven by work inputs to compressors and blowers. The analysis shows the irreversible entropy production in the various units and, in turn, the added work inputs required as a consequence thereof. Furthermore, a comparison is made with an ideal process of the same type, wherein all irreversibilities are reduced to the minimum possible, subject to the constraints imposed by (a) the use of a tower, and (b) the properties of the flowing streams. 

The Element.—The production of singlet oxygen by three different methods has been announced. The first article describes a relatively cheap method of producing excited oxygen by subjecting ordinary oxygen, under low pressure, to a... 

A prime example of the sensitivity of a metal to the nature of its support is provided by the synthesis of methanol and other oxygenated products from CO + H2 on Pd and Rh catalysts. " It is clearly necessary to use a support having basic character in order to achieve high selectivity, but whether this is because of a spillover or bifunctional mechanism, or because of a real metal-support interaction, is unclear at the present time, but in view of the proven involvement of the support in CO2 hydrogenation the former possibility certainly cannot be discounted. This subject is being covered by Ponec and Poels in a companion article in this volume and will therefore not be taken further here. 

Application of oxygen indicators would be particularly useful for indicating the end of shelf-life of a wide variety of additive-free products subject to both oxidative and microbial attack (Yoshikawa et al., 1982). 

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