Results 271 to 280 of about 72,853 (343)
Some of the next articles are maybe not open access.
The Crystalline State of Macromolecular Substances
Angewandte Chemie International Edition in English, 1974AbstractUnlike low molecular weight substances, high polymers do not crystallize completely. However long the crystallization process is continued, they still consist of a mixture of crystalline and non crystalline regions. In the undrawn material, these regions form larger units which are known as spherulites.
openaire +1 more source
Chapter 49 Macromolecular substances and plastics
1975Publisher Summary This chapter discusses macromolecular substances and plastics. In industry, gel permeation chromatography (GPC) serves as a method for characterizing and analyzing new polymeric products and for controlling the quality of standard products (Harmon).
M. Kubín, J. Čoupek
openaire +1 more source
SORPTION AND CHROMATOGRAPHY OF MACROMOLECULAR SUBSTANCES
Russian Chemical Reviews, 1961CONTENTS I. Introduction 612 II. Elution chromatography 613 III. Frontal chromatography 614 IV. New chromatographic methods 615 V. Polyelectrolytes 616 VI.
openaire +1 more source
Synthesis of Macromolecular Substances by Addition Polymerization
2001As already explained, polymerization reactions can proceed by various mechanisms and can be catalyzed by initiators of different kinds. For addition polymerization of single compounds, initiation of chains may occur via radical, cationic, anionic, or so-called coordinative-acting initiators, but some monomers will not polymerize by more than one ...
Dietrich Braun +2 more
openaire +1 more source
, 2000 Macromolecular changes of humic substances induced by interaction with organic acids
European Journal of Soil Science, 1996Summary Two different humic materials, one from a forest soil and the other from wormcasts, were used to study the influence of mineral and organic acids on the conformational properties of humic substances. The macromolecular changes were followed by low pressure gel permeation chromatography after titrating ...
PICCOLO A +2 more
openaire +1 more source
Urinary Macromolecular-Inhibitory-Substances of Calcium-Oxalate-Monohydrate Crystal Growth
1989It is well known that urinary glycosaminoglycans (GAG) exert inhibitory activity on crystal growth and aggregation. The purpose of this study was to evaluate the inhibitory activity of GAG in a natural form, namely as proteoglycan or glycoprotein.
S. Nishio +4 more
openaire +1 more source
Modes of Absorption of Macromolecular Substances
1995When we speak about absorption of macromolecular substances we must take into consideration the barriers of the gastrointestinal tract which hinder their uptake and transportation into the lymphatics and the blood. These barriers can be differentiated into morphological and functional barriers.
openaire +1 more source
Soil Science, 2001
The commonly accepted polymeric nature of humic substances is still a matter of debate. In this work, both humic matter of different origin and undisputed neutral (polysaccharides) and negatively charged (polystyrenesulphonates) polymers of known molecular weight were studied by high performance size exclusion chromatography after dissolution in mobile
Alessandro Piccolo +2 more
openaire +3 more sources
The commonly accepted polymeric nature of humic substances is still a matter of debate. In this work, both humic matter of different origin and undisputed neutral (polysaccharides) and negatively charged (polystyrenesulphonates) polymers of known molecular weight were studied by high performance size exclusion chromatography after dissolution in mobile
Alessandro Piccolo +2 more
openaire +3 more sources
A new phenomenon in flow birefringence of solutions of macromolecular substances
Journal of Polymer Science, 1953AbstractMeasurements on flow birefringence of solutions of polyvinyl chloride in cyclohexanone revealed that the angle of orientation increases with decreasing concentration of the solution. That this surprising effect was not due to constructional or experimental errors was demonstrated by results obtained with polystyrene, which were in agreement ...
E. J. Arlman, W. Boog, D. J. Coumou
openaire +1 more source