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Determination of the degree of polymerization of leucoanthocyanidins
Phytochemistry, 1968Abstract From studying a series of hawthron condensed tannins, it has been found that the colorimetric method for determining the degree of polymerization of flavans based on the transformation of leucoanthocyanidins into anthocyanidins (V/LA coefficient) gives much less reliable results than molecular sieving and the colorimetric method based on the
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The calculation of degrees of polymerization of fractionated polymers
Die Makromolekulare Chemie, 1963AbstractEquations are derived which permit the calculation of number and weight average degrees of polymerization for the low and high molecular weight fractions obtained by dichotomy of the molecular weight distribution, at any chosen molecular size, of a polymer having the “most probable” type of distribution.
A. D. Jenkins, Joan Pumfrey
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Degree of polymerization in two-dimensional assemblies
Macromolecules, 1991Etude de l'influence des concentrations en amorceur et en monomere sur le degre de polymerisation des polymeres obtenus par polymerisation radicalaire d'une couche bimoleculaire d'acryloylphosphatidylcholine. Les resultats suggerent que la terminaison des polymerisations de couches bimoleculaires de lipides a lieu surtout par reaction avec des ...
Todd D. Sells, David F. O'Brien
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Methods for Determining the Degree of Polymerization of Flavans
Nature, 1963Freudenberg1, Hergert2 and Hathway3 have each suggested several ways in which catechins and related compounds might polymerize to yield condensed tannins. Of these, oxidative condensation3, either with or without enzyme catalysis, appears to be the most likely way in which polymerization occurs in vivo; for example, in plum leaves during the course of ...
JUDITH L. GOLDSTEIN, T. SWAIN
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Effect of acid-chlorite delignification on cellulose degree of polymerization
Bioresource Technology, 2010Two types of pure cellulose, Avicel PH-101 and Whatman filter paper, were treated with an acid-chlorite delignification procedure in the presence of varying amounts of incorporated lignin, and the molecular weight distributions and degrees of polymerization (DP) of derivatized cellulose were determined by gel permeation chromatography (GPC).
Christopher A, Hubbell +1 more
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Maxima of degree of polymerization in equilibrium systems
Die Makromolekulare Chemie, 1963AbstractPlots of the degree of polymerization vs. temperature may show maxima in systems polymerizing under equilibrium conditions. It is shown that an equation correlating the temperature at which the maximum occurs with the thermodynamic constants of the polymerizing system, which was previously developed for the autoinitiated polymerization of ...
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Degree of polymerization of the CaAl2Si2O8 aluminosilicate glass
Glass Physics and Chemistry, 2006The pressure dependence of the refractive index for a glass of the composition 0.50SiO2 · 0.25Al2O3 · 0.25CaO at pressures up to 5.0 GPa is determined using a polarizing interference microscope and an apparatus with diamond anvils. The densities and compressibilities of the glass are calculated from the measured refractive indices within the framework ...
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Degree of Polymerization of Aluminosilicate Glasses and Melts
Glass Physics and Chemistry, 2004This paper presents the results of analyzing the data available in the literature on the structure and properties of silicate glasses and melts that contain Ti4+, Al3+, and Fe3+ cations in addition to alkali and alkaline-earth cations. It is established that the aforementioned multivalent cations in glasses and melts have a coordination number of four ...
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Determination of the degree of polymerization of oligosaccharides
Analytical Biochemistry, 1963L, STEWART, P, NORDIN
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Effect of crystallinity and degree of polymerization of cellulose on enzymatic saccharification
Biotechnology and Bioengineering, 1984AbstractLignocellulose materials were pretreated by methods known to improve enzymatic saccharification, and the percentage crystallinity (x‐ray diffraction) and degree of polymerization were measured. It was observed that although the percentage crystallinity of cellulose was not altered by alkaline explosion (AE), carbon dioxide explosion (CE), ozone,
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