Compounding advantages/disadvantages

A novel and more general method to enable biocatalyzed conversion and synthesis of hydrophobic compounds involves the use of gel-stabilized aqueous-organic two-phase systems [8], Features, advantages, disadvantages, and perspectives of this method in asymmetric synthesis will be discussed in this chapter, illustrated for the stereoselective benzoin condensation and the reduction of ketones catalyzed by thiamine pyrophosphate (TPP)-dependent lyases and NAD(P)H-dependent alcohol dehydrogenases, respectively. 

Method Type of Compound Concentrated Advantage Disadvantage Selected References... 

The advantage of GC/MS is the capacity to separate these isomeric (or isobaric) compounds. Its disadvantage is, among others, to introduce coeluting compounds, leading to uncertainties and to a reduced sensitivity (in the case where high resolution becomes necessary) this no longer occurs when MS/MS is utilized. 

Element or Compound Advantageous Effects Disadvantageous Effects... 

The application of inorganic electroactive compounds in aqueous RFBs have been the subject of the vast majority of the literature to date. Table 2 summarizes the standard electrode potentials of common redox couples while Table 3 highlights prominent cell chemistries based on combinations of these redox couples. Of these chemistries, iron-chromium (ICB) [33], polysulfide-bromide (PSB) [14], and aU-vanadium (VRB) [31] systems have yielded industry-level demonstrations (order of 100 kW-10 MW). Below, these RFB chemistries are introduced in some detail with key advantages, disadvantages, and challenges highlighted. 

Hydrofining has all the advantages of acid treating without the disadvantages. For example, acid treating does not readily remove refractory sulfur compounds such as thiophene the treated products must be rerun to remove polymers with a consequent yield loss and disposal of the acid sludges is a serious problem. 

The parameterization process may be done sequentially or in a combined fashion. In the sequential method a certain class of compound, such as hydrocarbons, is parameterized first. These parameters are held fixed, and a new class of compound, for example alcohols and ethers, is then parameterized. Tins method is in line with the basic assumption of force fields parameters are transferable. The advantage is that only a fairly small number of parameters are fitted at a time. The ErrF is therefore a relatively low-dimensional function, and one can be reasonably certain that a good minimum has been found (although it may not be the global minimum). The disadvantage is that the final set of parameters necessarily provides a poorer fit (as defined from the value of the ErrF) than if all the parameters are fitted simultaneously. 

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