high temperature, high radiance, low vapor pressure, and lack of precipitation in most months characterize arid ecosystems. under these conditions, tree crops such as pistachio suffer from drought combined with salinity stress. in order to investigation effects of combined salinity and drought stress on function of photosynthetic apparatus, mutica pistachio (pistacia mutica) seedlings were subj...

and elevated ozone on tissue water relations of mature clones of a fast-growing genotype of ponderosa pine (Pinus ponderosa Dougl. ex Laws.) and their half-sib seedlings. Whole seedlings and branches of mature trees were exposed to acid rain (pH 5.1 and 3.0) and ozone (ambient and twice-ambient) treatments in open-bottomed chambers. The acid rain treatment was applied to foliage weekly from Jan...

We have measured the concentration dependence of the osmotic pressure for solutions of core histones in 2.0 M NaC1, pH 8.0, over the concentration range from 1 to 20 mg/ml at 25°C. The ratio of the osmotic pressure to the protein concentration is nearly constant over this range, with a value corresponding to an apparent number average molecular weight of 75,000. Gel filtration of a typical core...

Polyelectrolyte gels are known to undergo significant conformational changes in response to external stimuli such as pH, temperature, or the dielectric constant. Specifically, an increase of the degree of ionization associated with an increasing number of counterions leads to swelling of the network. For a macroscopically large gel, which is electrostatically neutral in its interior, swelling i...

Human red blood cells have been incubated in the presence of nystatin, which allows Na and K, as well as Cl and pH to equilibrate rapidly when cell volume is set with external impermeant sucrose. The intracellular mean ionic activity coefficients, relative to values in the extracellular solution, for KCl and NaCl are 1.01 +/- 0.02 and 0.99 +/- 0.02 (SD, n = 10), respectively, and are independen...

this articles is comprised of two parts: a) an experimental investigation on the behavior of an acrylic gel under dc electric field and b) a physico - mathematical description.a) gel rods made of poly [acrylamide-co-bisacrylamide] were partially hydrolyzed to different extents at ph 12 by teteramethylethylene diamine. equlibrium properties of the resulting gels rods (water content, number of ca...

hard gelatin capsule filled with acetaminophen, osmotic agent (sorbitol), a release promoter (sodium dodecyl sulfate), coated with a semipermeable cellulose acetate membrane containing a hydrophobic plasticizer (castor oil) and sealed with white bees wax plug was designed. when placed in the sink water penetrates the membrane, dissolves the osmotic agent and increases the osmotic pressure insid...

ABSTRACT: The combination of pulsed vacuum osmotic dehydration and microwave drying of garlic bulbs were examined. The response surface methodology (RSM) was used to determine the effect of NaCl concentration (8%-20%), osmotic solution temperature (25-65°C), operation pressure (240-830 mbar), immersion time (20-300 min) and microwave power level (100-600 W) on water loss (WL), solids gain (SG),...

The effect of pH on membrane fouling in a submerged membrane bioreactor (MBR) was investigated in this study. It was found that, pH increase slightly increased the resistance of virgin membrane and fouled membrane. Pore clogging resistance was quite low, which was not apparently affected by the pH variation. Lower pH resulted in higher adherence of sludge flocs on membrane surface. Thermodynami...

Numerous contributions regarding the pathogenesis of ascites and edema have been made since Starling's first description of the balance between serum and tissue hydrostatic and osmotic forces. The original concept (1) proposed that, at equilibrium, serum protein osmotic pressure minus tissue fluid osmotic pressure equals capillary hydrostatic pressure minus tissue hydrostatic pressure. Direct a...