Conformation and aggregation

Conformations and aggregate structures of sorbed natural organic matter on muscovite and hematite. Geochim. Cosmo-chim. Ada 65 1047-1057 Nanzyo, M. Watanabe,Y. (1981) Material balance associated with phosphate sorption by amorphous clays, silica-alumina gel and synthetic goethite. Soil Sd. Plant Nutr. 27 329-337... 

A-Fl-FFF/MALLS has been used for the determination of the molar mass and size distribution of dextrans and pullulans of various molar masses [473], hy-droxypropylmethylcelluloses [474] and K-carrageenan in different conformations and aggregation states [475]. 

As discussed earlier, different solvents may result in distinct conformations and aggregation styles of the polymer chains in the solution. It is expected that such differences will be carried on into the spun film. The direct evidence for this is the solvent dependence of the surface energy for spin-coated polymer films. Shi et al.17 have observed that the contact angles (86°-87°) between H2O and the polymer films spun from THF and CHCI3 are significantly smaller than those (average 95°) spun from aromatic solvents (Table 6.1). This indicates that these films have different surface energies. On the other hand, an MEH-PPV film spun... 

Namjesnik-Dejanovic K, Maurice PA (2001) Conformational and aggregate structures of sorbed natural organic matter on muscovite and hematite. Geochim Cosmochim Acta 65 1047-1057 Naves de Brito A, Svensson S, Correia N, Keane MP, Agren H, Sairanen OP, Kivimaki A, Aksela S (1992) X-ray induced electron yield spectrum of thin films of 1,3-trans-butadiene and 1,3,5-trans-hexatriene. J Electron Spect Rel Phen 59 293-305... 

Barrow, C.J., Yasuda, A., Kermy, P.T.M., Zagorski, M.G. Solution conformations and aggregational properties of synthetic amyloid, 6-peptides of Alzheimer s disease, J. Mol. Biol. 1992, 225,1075-93. 

FlFFF has been found to be very useful for separation of proteins. In addition to MW and size, molecular conformation and aggregation can be investigated. 

Alvarez-Puebla, R. A., C. Valenzuela-Calahorro, and J. J. Garrido. 2006. Theoretical study on fulvic acid structure, conformation and aggregation a molecular modelling approach. Science of the Total Environment 358, no. 1-3 243-254. 

Aharoni, C., and D. L. Sparks. 1991. Kinetics of soil chemical reactions—A theoretical treatment. In Rates of Soil Chemical Processes, eds. D. L. Sparks and D. L. Suarez, 19-59. SSSA Special Publications 27. Madison, Wl Soil Science Society of America, https // dl.sciencesocieties.oig/publications/books/pdfs/sssaspecialpubl/ratesofsoilchem/19. Alvarez-Puebla, R. A., C. Valenzuela-Calahorro, and J. J. Garrido. 2006. Theoretical study on fulvic acid structure, conformation and aggregation. A molecular modelling approach. The Science of the Toted Environment 358, no. 1-3 243-254. 

The novel features introduced into coordination chemistry by study of the colloidal ligands which are critical in soils and natural waters are three. First, we must deal with a distribution of similar but distinct binding sites. Second, polyelectrolyte effects are prominent. Third, the ligands undergo conformational and aggregational equilibria which are influenced by metal ion uptake. 

Finally, it should be mentioned that polymers may undergo transitions from one conformation to another, or from one aggregation state to another, if their environment is altered (e.g. pH, ionic strength, solvent composition, or temperature). The conformation and aggregation state of polymers play a major role in determining their functional attributes, and so it is usually important that scientists are aware of the molecular characteristics of the polymers present in each particular emulsion. 

Hesse S, Suhm MA (2009) Conformation and aggregation of proline esters and their aromatic homologs pyramidal vs. planar RR N-H in hydrogen bonds. Z Phys Chem 223 579... 

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