Weight chain length distribution

Because the higher alcohols are made by a number of processes and from different raw materials, analytical procedures are designed to yield three kinds of information the carbon chain length distribution, or combining weight, of the alcohols present the purity of the material and the presence of minor impurities and contaminants that would interfere with subsequent use of the product. Analytical methods and characterization of alcohols have been summarized (13). 

Wj. weight chain length distribution of the primary molecules,... 

A series of structurally characterized di-yttrium(III) complexes bearing alkoxy-derivatized triazacyclononane ligands have been examined as initiators for lactone ROP.886 Both (296) and (297) are active for the polymerization of rac-LA at RT, but little control is afforded over molecular weights. Chain length distributions are broad, (Mw/Mn= 1.5-2.2) and attempts to identify the initiating group via end-group analysis have not been successful. 

Fig. 49 Effect of the width of a uniform chain length distribution on fibre strength. The width of the block w is centred at the end of the value of the molecular weight, expressed as the length of the monomeric unit. For example, for the point on the curve zw=100 m.u. and 12.5wz"1=20, it means that the total block width w=160 m.u. hence, the range of the distribution, which is centred at zw=100 m.u., is from z=20 up to z=180. Note that for a uniform distribution zw=zn...

Typical weight per cent chain length distributions based on 20 80 tallow coconut fatty acid chain distribution specified for sodium acyl isethionate specified for the Monsavon bar [9], and the purely coconut fatty acid source for SCI. 

A useful alternate to the Mayo plot for determining Cs (as well as other transfer constants) is the chain length distribution (CLD) method based on the molecular weight distributions obtained from size exclusion chromatography (SEC) [Christie and Gilbert, 1996, 1997 Heuts et al., 1998, 1999 Moad and Moad, 1996]. The limiting slope AHIGH of a... 

The aim of this contribution is to investigate the influence of concentration, chain length, molecular weight distribution, chemical nature, solvent quality, aging effects, etc. on drag reduction as has been proposed, e.g., by Kulicke, Klein (1985). 

Influence of Chain Length, Molecular Weight, and Molecular Weight Distribution... 

The A plus Bj chains dominate the chain length distributions in amylopectins both by weight (58-74%) and by number (85-93%), compared with the sum of the long B chains (see Table 10.8). The A and Bj chains are believed to occur within one cluster, while the B2 and B3 chains transverse two and three clusters, respectively. The B4 chains and beyond are small in number and were not detected by the end group labeling protocol. However, the weight-percent of B4 chains with DPn above —50 (DPW —80) is measurable.217,224,225... 

Fig. 11 Calculated chain length distribution on a number and weight basis, for n=0.500...

Fig. 12 Instantaneous chain length distribution on a number and weight basis, where dead chains are formed by disproportionation termination. The value of n is increased by decreasing the bimolecular termination rate...

We will discuss first whether there is an absolutely definite limit of action for all amylases. In the case of the action of /5-amylase on starch and on a-dextrins this question seems to be settled, but in the case of the malt a-amylase the answer is less certain. But certainly the action of the malt amylase practically stops at a certain limit. There is, however, almost always a very slow further action. It is possible that this slow saccharification of the limit dextrins is due not to the amylases but to other carbohydrases which have no action on starch but which are capable of attacking products with short chains. Under all circumstances it must be kept in mind that when in an experiment the saccharification for practical purposes has stopped and the limit dextrins have been isolated, this does not necessarily mean that the limit dextrins will not be further attacked by the enzyme used. But the velocity of this action is certainly very small compared with the velocity of the action on starch. Thus, it must be admitted that experiments involving the isolation of the limit dextrins after the action of a certain amylase on starch are in most cases not strictly reproducible. TJie total yield and chain length distribution of limit dextrins may vary, but their general character is not affected. If a limit dextrin produced by a certain amylase is treated with the same enzyme for a very long time, it is very often transformed to another limit dextrin of lower molecular weight with concomi-... 

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