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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.
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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
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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
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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
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Macromolecular material (humic substance) in the water column and sediments
Marine Chemistry, 1992Abstract The progress during the past 10–15 years in the studies of organic macromolecules (humic substances, HS) in seawater and sediments is reviewed. The review describes the advances in the characterization of seawater and sedimentary HS, HS formation models, studies on the geochemical role of marine HS, and future research needs.
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MACROMOLECULAR PROPERTIES OF SOIL HUMIC SUBSTANCES: FACT, FICTION, AND OPINION
Soil Science, 1999A critical review of 'random coil' and 'self-associating aggregate' models and of earlier concepts of the macromolecular structure of humic substances (HS) is undertaken as a result of the development of more recent information and hypotheses.
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Chemical Engineering Science, 2009
Abstract The vibrating membrane bioreactor (VMBR) system facilitates the possibility of conducting a separation of macromolecules (BSA) from larger biological components (yeast cells) with a relatively high and stable macromolecular transmission at sub-critical flux. This is not possible to achieve for a static non-vibrating membrane module.
Søren Prip Beier, Gunnar Jonsson
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Abstract The vibrating membrane bioreactor (VMBR) system facilitates the possibility of conducting a separation of macromolecules (BSA) from larger biological components (yeast cells) with a relatively high and stable macromolecular transmission at sub-critical flux. This is not possible to achieve for a static non-vibrating membrane module.
Søren Prip Beier, Gunnar Jonsson
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Affinity Chromatography of Macromolecular Substances on Adsorbents Bearing Carbohydrate Ligands
1981Publisher Summary This chapter provides information on the methods for preparing affinity adsorbents having carbohydrate ligands and illustrates the use of these adsorbents for the purification of representative, macromolecular substances. Affinity chromatography is possible because of the stereospecific interactions that can occur between the ...
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AGGREGATION PATTERNS AND MACROMOLECULAR MORPHOLOGY OF HUMIC SUBSTANCES: A FRACTAL APPROACH
Soil Science, 1999Fractal geometry provides a powerful means for the quantitative description of heterogeneous and highly irregular systems encountered in nature. Humic substances represent a typical class of natural compounds that may be amenable to a fractal description because of their well known physical and chemical heterogeneity and molecular complexity.
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Kinetics of brain receptor binding inhibition by endogenous macromolecular substances [proceedings].
Archives internationales de physiologie et de biochimie, 1980 P, Van Gompel, J E, Leysen
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2001
Condensation polymerizations (polycondensations) are stepwise reactions between bifunctional or polyfunctional components, with elimination of simple molecules such as water or alcohol and the formation of macromolecular substances. For the preparation of linear condensation polymers from bifunctional compounds (the same considerations apply to ...
Dietrich Braun +2 more
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Condensation polymerizations (polycondensations) are stepwise reactions between bifunctional or polyfunctional components, with elimination of simple molecules such as water or alcohol and the formation of macromolecular substances. For the preparation of linear condensation polymers from bifunctional compounds (the same considerations apply to ...
Dietrich Braun +2 more
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