Residue characterization

The above TGA and elemental analysis studies are consistent with Van Krevelen s two step model for polymer charring (2) in which a polymer first rapidly decomposes at 500°C to fuel gases and a primary char residue characterized by modestly high hydrogen content. On further heating above 550°C, this primary char is slowly converted in a second step to a nearly pure carbon residue by the loss of this hydrogen. 

Equation (10) is exact in the absence of local motion. It provides a good approximation for the protein core residues, characterized by restricted mobility in the protein backbone in this case both J(0) and /(local motion to p in Eq. (10) is canceled out The approach described here is rather general and accommodates both large 1) and small < 1) molecules and mole-... 

The two situations above do occur for many mutations in bamase. We can simply go around the structure checking fully native or fully denatured at the relevant regions and so get a detailed residue-by-residue characterization of its folding intermediate and transition state. Each mutation is a reporter group for what is happening at the site of mutation during the folding pathway. 

Fleischmann, T.J., J.C. Toth, and B. Simoneaux (1990). Prometryn - Nature of the Residues Characterization of Metabolites Present in Field Grown Celery. Submitted to USEPA. 

CCB was fractionated into six asphaltene-free distillate fractions of varying boiling ranges and an asphaltene-rich non-distillable residue. Characterization of the distillate and the non-distillable fractions indicate significant differences in the asphaltene, ash, aromaticity, molecular weight and aromatic ring distributions. 

Keywords trichlorosilane, tetrachlorosilane, direct process, direct process residue, characterization, shock-sensitive, hydrolysis, pyrophoric... 

Figures 10 and 11 show some examples of model predictions of the feedstock characterization of crude distillation residues. Figure 10 compares model predictions with the experimental distillation curves of three Arabian atmospheric residues. Figure 11 shows the model ability in predicting the aromatic carbon content and the H/C of different feeds in comparison with some NMR data. A more detailed description and discussion of this residue characterization is reported elsewhere (Bozzano et al., 1995, 1998).

Two conserved signature sequences containing histidine motifs (His-Xaa-Val(Ile)-Xaa-Lys and Gly-Xaa-His-Ile(Leu,Val)-Ile), which are separated by a stretch of about 70-85 amino acids containing a few other conserved residues, characterize the catalytic core of all parvulins. In various plants, one member corresponds... 

Metal ion association constants Kassoc (Kassoc = in the various Fe(II)-M(II) derivatives of GpdQ (M = Co, Mn, Zn, Cd) were determined at various pH values. A bell-shaped pH dependence was observed for the Fe(II)Zn(II), Fe(II)-Co(II) and Fe(II)Mn(II) derivatives, which indicates that (at least) two ionisable residues (characterized by pKai and pKa2) in the enzyme contribute to binding of metal ions. An overview of the pKa values of amino acid residues near the active site in GpdQ is shown in Table 3.6. 

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