A significantly improved apparatus for the isopiestic measurement of thermodynamic activities at elevated temperatures is described. Details of the new design and of an analysis of the propagation of the experimental errors are presented. The apparatus was tested by measurements of calcium chloride against sodium chloride at 353.15 K. Accuracies of better than 0.1% in the osmotic coefficient ar...

The classic analysis by Anderson and Malone (Biophys J 14: 957-982, 1974) of the osmotic flow across membranes with long circular cylindrical pores is extended to a fiber matrix layer wherein the confining boundaries are the fibers themselves. The equivalent of the well-known result for the reflection coefficient sigma0 = (1 - phi)2, where phi is the partition coefficient, is derived for a peri...

Water permeability coefficients of dog, cat, and beef red cell membranes have been measured under an osmotic pressure gradient. The measurements employed a rapid reaction stop flow apparatus with which cell shrinking was measured under a relative osmotic pressure gradient of 1.25 to 1.64 times the isosmolar concentration. For the dog red cell the osmotic permeability coefficient is 0.36 cm(4)/(...

Membrane osmometry is used to measure osmotic pressures of dilute solutions containing quasi-spherical CdSe nanocrystals covered with polymer brushes in toluene in the range 31 to 45°C. Osmotic-pressure data, as a function of nanocrystal concentration, yield the molecular weight and the osmotic second virial coefficient of the nanocrystals; the latter is related to the potential of mean force b...

dehydration is one of the most common preservation methods for button mushroom. dried mushroom slice and powder is used in formulation of soups and sauces. in this study, the effect of osmotic pretreatment on drying kinetics of button mushrooms was studied. thin slices of mushroom were immersed in osmotic solution containing 5% sodium chloride and 0.5% calcium chloride at a temperature 40 °c fo...

abstract: in this study the reliability of using response surface-neural network method to predict the osmotic dehydration properties of crookneck squash has been investigated. in order to carry out this project, the osmotic solution concentration, the osmotic solution temperature and immersion time were chosen as inputs and solid gain and water loss were selected as outputs of the designed net...

New model xDLVO-CGhybr calculating second osmotic virial coefficient of protein solutions is developed. Data calculated agrees well with experiments due to accurate estimation electrostatic protein–protein interactions using a hybrid methodology.

The activity coefficient is largely considered an empirical parameter that was traditionally introduced to correct the non-ideality observed in thermodynamic systems such as osmotic pressure. Here, the activity coefficient of free-solvent is related to physically realistic parameters and a mathematical expression is developed to directly predict the activity coefficients of free-solvent, for aq...