Carboxyl Chain

The simultaneous determination of LAS and its potential biodegradation intermediates of low molecular weight (C < 8), as sulfonated and non-sulfonated, has been performed by RP-HPLC-UV using a gradient regime with the mobile phase at pH 2.2 [29]. Compound elution with the same number of carbon atoms in the carboxylic chain was as follows SPCs, hydrophenyl carboxylic acids and finally phenylcarboxylic acids. 

Oxidation is the main route responsible for the shortening of the carboxylic chain, and consequently the reagents with an odd number of... 

SPCs of medium carboxylic chain lengths (C6-C8) are the most persistent surfactants and constitute more than 70% of the total SPC detected in water. In sediments, the longer-chain SPC (C9-C1 l) are the most abundant ones. The SPC metabolites are more evenly distributed in the water column than the parent LAS. 

Figure 14.6 Simplified structure for random ethylene-acrylic ester-glycidyl methacrylate terpolymers which are effective rubber tougheners for PET compounds. The ethylene-acrylic ester segments provide elastomeric properties while the glycidyl methacrylate functionalities enable reactive grafting to the PET matrix via the hydroxyl and carboxyl chain ends of the latter...

H NMR data from these seven sites are presented by spectral peak-height ratios in Table III. The sites were listed in order of increasing aromatic plus olefinic carbon percentages. Fulvic acids from all the lake samples are much lower in aromatic plus oleflnic carbon content than those from river samples. These results confirm the hypothesis that autothonous inputs result in dissolved humic substances that have a low aromatic plus oleflnic carbon content. The lake samples also are lower in the ratios of peak 2 (carboxylated chains and aliphatic ketones), peak 3 (carbohydrates), and peak 4 (phenolic tannins and lignins) to peak 1 (branched methyl groups and alicyclic ali-phatics) than are the river samples. 

However, in most cases, propagation takes place through carboxylate chain-ends, although coexistence with alkoxide chain ends in the beginning of ROP... 

Based on this assumption and conformation C (Figure 2) we can calculate that the sample MD 120 has = 15 % of the chains entrapped in the micelle. This is in agreement with the fact that this diacid sample has the highest hydroxy-to-acid index ratio and thus a slight excess of non-carboxylated chains (see Table I). 

We have synthesised 4-(8-morpholin)capriloyl-Neu5Ac-o2Me lo [28], wishing us a long carboxylic chain with a polar end would form specific interactions with the protein, or, in alternative, to have a compound which shows resistance to the NA. 

One of the most successful families is represented by a series of polymers built from the linkage of metallic carboxylate chains through 4,4 -bipyridine spacers [ 176]. As an example, the coordination polymer [Cu(C4H O )(4,4 -bpyifH O) ] is formed by the connection of chains of Cu(II) metal ions bridged by succinate ligands through 4,4 -bipyridine molecules. This 3-D framework shows weak ferromagnetic interactions and channels, in which the water molecules are located. 

Sf>ecific for carboxylic chains and hydroxy-carboxylic acids More intense signals in archaeological samples, shifts... 

Same functional groups, carboxylic chains and hydroxyl-carboxylic acids ... 

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