Traditional batch method

The reaction(s) are sufficiently slow so that the reactant concentrations will not change appreciably during centrifugation and sampling steps. Even in the case of rapid reactions, this traditional batch method can still be used to study sorption after attainment of steady-state conditions. 

The process of phase inversion has received considerable attention (see McDowall (1953) and Wilbey (1994) for a detailed discussion). Briefly, churning methods can be divided into (1) traditional batch methods and (2) continuous methods. 

To study rapid reactions, traditional batch and flow techniques are inadequate. However, the development of stopped flow, electric field pulse, and particularly pressure-jump relaxation techniques have made the study of rapid reactions possible (Chapter 4). German and Japanese workers have very successfully studied exchange and sorption-desorption reactions on oxides and zeolites using these techniques. In addition to being able to study rapid reaction rates, one can obtain chemical kinetics parameters. The use of these methods by soil and environmental scientists would provide much needed mechanistic information about sorption processes. 

There are several processes for producing effervescent wine, but only three are of importance in California. These are the classic or traditional methode champenoise, the transfer system, and the bulk or Charmat process. These are all batch methods for making sparkling wine. The continuous fermentation method, used extensively in the Soviet Union, is not employed in California. Little artificially carbonated wine is made in California. 

In addition, supported reagents have been demonstrated to be effective under reaction conditions when either thermal or microwave heating - is employed. They have also been utilised in traditional batch synthesis, stop-flow methods and continuous flow processes. ° However, one caveat is that the immobilisation of reagents can change their reactivity. For example, polymer-supported borohydride selectively reduces a,P-unsaturated carbonyl compounds to the a,P-unsaturated alcohoF in contrast to the behaviour of the solution-phase counterpart, which additionally causes double bond reduction. 

The greatest advantage of on-line digestion methods over batch methods is that they minimize the problem of acid fumes produced during the digestion of biological samples in the traditional Teflon vessels used in batch treatments. Gas evolution in the on-line methods, however, can lead to problems resulting in pressure build-up and disturbances... 

The rapid analysis of food products is crucial in food processing in order to allow manufacturing processes to be adjusted while production is underway and to ensure that product quality and regulatory specifications are adhered to. Traditional chemical methods [50], such as the Mojonnier method, which can be used to analyse for fat and moisture, the Soxhlet method for analysis of fat, or the vacuum-oven method for moistm-e determination, all present constraints in terms of time, manpower, and/or the need for substantial amounts of solvents. If timely analytical results are not available, batches in production may need to be reworked if out of specification, involving additional time and expense. For these very practical reasons, there is a need... 

Fatty Acids. The above process is an old and direct method by which to make soap but if fatty acids are wanted, and their use is increasing, the addition of alkali must be avoided unless subsequent treatment with acid at additional expense iis to be incurred. For making these fatty acids several processes may be used, the autoclave and the traditional Twitched method, which are batch operations, and the more modem continuous-countercurrent procedures developed by Colgate-Palmolive-Peet and by The Procter Gamble Company. Darkening of the resulting products from this type of operation is retarded by the use of hydroxy aromatic compounds as stabilizers. ... 

Enolates are powerful carbon nucleophiles and addition of enolates to carbonyl groups (aldol reactions) serve as a useful method for C-C bond formation. The Mukaiyama aldol reactions involving fluoride ion-promoted addition of silyl enolates to aldehydes are very popular and are frequently employed in the construction of carbon skeletons in organic synthesis [ 1 ]. The Mukaiyama aldol reaction with the silyl enol ether of cyclohexanone and 4-bromobenzaldehyde can be performed based on the electroosmotic flow (EOF) technique with a four-chaimel microstructured flow reactor (charmel dimensions 100 x 50pm). The reactor was prepared using a standard fabrication procedure developed at the University of Hull [2, 3]. Based on GC-MS analysis, quantitative conversion of the starting material was achieved in 20 min, whereas in the case with a traditional batch system a quantitative yield was obtained only when an extended reaction time of 24 h was employed (Figure 5.1). 

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