Abstraction of water

The term anhydride or anhydrous aeid is applied to the renduo obtained by the abstraction of water from one or two molecules of an oxygen acid. Thus,... 

Pyrophosphoric acid can be considered as a member of a series of polyphosphoric acids. They can be derived from ordinary phosphoric acid by the abstraction of water, thus ... 

Hygroscopicity of some hydrophilic bases such as the polyoxyethylene glycols results in the abstraction of water from the rectal mucosa. This causes a stinging sensation and discomfort and probably affects the passage of drugs across the rectal mucosa. 

On cooling the hollow spheres gelatinize and the spontaneous degeneration now no longer follows. Invagination processes now occur in these gelatinized objects under all sorts of conditions (Fig. 32). Among these phenomena are some, the cause of which one is inclined to seek in an osmotic abstraction of water from the vacuole. The inv ination is then very deep (for example Fig. 32d). This occurs, for example... 

Finally there are also circumstances, which lead to invagination, which are such that one can with certainty leave an osmotic abstraction of water from the vacuole out of consideration. This occurs, for example, on adding distilled water to the medium in which the gelatinized hollow spheres are suspended the invagination produced, usually not very deep, (Fig. 326) again belongs to the type which rapidly disappears spontaneously but too little data are yet available for an explanation. 

As long ago as 1845, Fleitmann andHenneberg [19] introduced the concept of polyphosphoric acids which could be derived from ordinary (ortho)phosphoric acid by the abstraction of water. 

In 2009, Breit et al. [109d] have extended the enamine strategy to unactivated allyl alcohols as substrates for the allyhc substitution (Scheme 12.47). When (d/l)-proline is used as the amine component, the carboxylic acid moiety in situ activates the allylic alcohol for abstraction of water and formation of a tt-allylpalladium complex. Subsequent nucleophilic attack of the enamine leads to the a-allylated ketones or aldehydes. Interestingly, the use of enantiopure prohne has no effect on the stereochemical outcome of the reaction with prochiral substrates. 

Any dangerous occurrence at a well other than a well sunk for the purpose of the abstraction of water. 

Section 24 of the Water Resources Act 1991 prohibits abstraction of water from streams or the ground except in pursuance of a licence granted by the Environment Agency. This offence is punishable by a fine of up to 5000 or on indictment, an unlimited fine. 

Fig. 10. Curves showing the probability of two independent successive abstractions of water molecules in the formation of hydration patches on NiS04 -7H20.

For NiS04 7H20 Garner considered that two successive abstractions of water molecules independent of each other are necessary to nucleate patches. The probability of two independent abstractions will increase with the square of the time (Fig. 10). 

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