1. A proteoglycan fraction (the proteoglycan subunit fraction) was prepared from extracts, with 0.15m-KCl (low-ionic-strength) and 0.5m-LaCl(3), 2.0m-CaCl(2) and 4.0m-guanidinium chloride (high-ionic-strength), of bovine nasal cartilage by equilibrium-density-gradient centrifugation, essentially as described by Hascall & Sajdera (1969). 2. The use of different centrifugation times showed that n...

soil colloid particles influence soil chemical and physical properties by their surface electrical charge. with respect to the importance of this issue from both agricultural and environmental points of view, charging behavior of a kaolinite sample was studied in the ph range of 4 to 10 and at three background electrolyte concentrations, including 0.005, 0.05, 0.5 m nacl, by potentiometric titr...

plants uptake boron (b) from the soil solution, in which boron concentration is controlled by adsorption and desorption reactions on soil organic and inorganic colloids. considering the importance of aluminosilicate minerals in ion adsorption and desorption reactions in soil, in this research, b adsorption behavior on kaolinite was studied as a function of equilibrium concentration, ph, kaolini...

The efflux of salt from human red blood cells suspended in isotonic sucrose plus low concentrations of salt, was measured under steady-state conditions. The relationship between the efflux and the log of the salt concentration can be fitted by two straight lines with a sharp inflection point, the steeper slope occurring at concentrations below 0.2 mM NaCl. The determining factor in the rate of ...

Understanding anion adsorption mechanisms is necessary to allow prediction of anion adsorption behavior. This study was conducted to evaluate the ability of the triple layer model, a chemical surface complexation model, to describe the effect of changes in solution ionic strength (0.01-1.0 M NaCl) and solution pH (3-11) on B adsorption by the iron oxide, goethite, the aluminum oxide, gibbsite, ...

The essential component of infectious prions is a misfolded protein termed PrPSc, which is produced by conformational change of a normal host protein, PrPC. It is currently unknown whether PrPSc molecules exist in a unique conformation or whether they are able to undergo additional conformational changes. Under commonly used experimental conditions, PrPSc molecules are characteristically protea...

Cystathionine-beta-synthase (CBS) domains are found in >4,000 proteins in species from all kingdoms of life, yet their functions are largely unknown. Tandem CBS domains are associated with membrane transport proteins, most notably members of the ATP-binding cassette (ABC) superfamily; voltage-gated chloride channels and transporters; cation efflux systems; and various enzymes, transcription fac...

Solution chemistry effects on surfactant micelle formation, surfactant sorption on kaolinite, and phenanthrene partitioning to surfactant micelles and sorbed surfactants were studied. For the anionic surfactant sodium dodecyl sulfate (SDS), critical micelle concentration (cmc) values decreased with increasing ionic strength but were unaffected by pH changes. For the nonionic surfactant Tween 80...

Two short non-self-complementary RNA duplexes have been probed extensively to assess whether the heat capacity change (DeltaCP) for RNA duplex formation is sensitive to the solution ionic strength. Isothermal titration calorimetry data for duplex formation were collected as a function of temperature to obtain the DeltaCP values under each condition. Ionic strength was varied by repeating the me...

OBJECTIVES In this study, we investigated the influence of ionic strength and natural organic matter (NOM) on aggregation and soil adsorption of citrate-coated silver nanoparticles (AgNPs). METHODS Time-resolved dynamic light scattering measurements and batch adsorption experiments were used to study their aggregation and soil adsorption behaviors, respectively. RESULTS The aggregation rate...