In this study, the effects of ionic strength on membrane fouling in a membrane bioreactor (MBR) were investigated. Ionic strength in range of 0.005-0.05mol/L exerted no apparent impacts on the resistance of virgin membrane, fouled membrane and pore clogging. Thermodynamic analysis showed existences of a secondary energy minimum and an energy barrier in the process of the sludge flocs approachin...

Quartz crystal impedance analysis has been developed as a technique to assess whether room-temperature ionic liquids are Newtonian fluids and as a small-volume method for determining the values of their viscosity-density product, rho eta. Changes in the impedance spectrum of a 5-MHz fundamental frequency quartz crystal induced by a water-miscible room-temperature ionic liquid, 1-butyl-3-methyli...

Pore clogging with Brownian particles is of wide interest in filtration processes. We perform experiments where model sub-micrometric pores are clogged using a Brownian suspension. We study the influence of the ionic strength on the clog formation dynamics. The erosion/drag force competition is also studied using a crossflow in the inlet channel. The way the clogs disintegrate after the cloggin...

The acidity constants of 4-(2-pyridylazo)resorcinol (PAR, Scheme 1) in binary mixtures of methanol–water at 25 ◦C and an ionic strength of 0.1 M have been determined spectrophotometrically. DATa ANalysis (DATAN) program applied for determination of acidity constants. As percent of methanol increases in solvent mixtures the pKa constants also increased. There is linear relationship between acidi...

The most important physico-chemical characteristics describing detergent micelles are the CMC value and the aggregation number. These parameters depend critically on external conditions such as pH, ionic strength, buffer composition or temperature. However, the influence of these conditions on CMC or aggregation number is a priori not to predict, but the most important parameter. This holds esp...

Calcium and ionic strength are both known to modify the force developed by skinned frog muscle fibers. To determine how these parameters affect the cross-bridge contraction mechanism, the isotonic velocity transients following step changes in load were studied in solutions in which calcium concentration and ionic strength were varied. Analysis of the motion showed that calcium has no effect on ...

We report real-time observations of the folding and melting of DNA by probing two active sites of a hairpin structure, the bases and the stem end, and using an ultrafast T-jump. Studies at different initial temperatures (before, during, and after melting) provide the time scale of water heating (<20 ps), single-strand destacking (700 ps to 2 ns), and hairpin destacking (microseconds and longer)...

The use of biotherapeutics, such as monoclonal antibodies, has markedly increased in recent years. It is thus essential that biotherapeutic production pipelines are as efficient as possible. For the production process, one of the major concerns is the propensity of a biotherapeutic antibody to aggregate. In addition to reducing bioactive material recovery, protein aggregation can have major eff...

Organisms exposed to altered salinity must be able to perceive osmolality change because metabolism has evolved to function optimally at specific intracellular ionic strength and composition. Such osmosensing comprises a complex physiological process involving many elements at organismal and cellular levels of organization. Input from numerous osmosensors is integrated to encode magnitude, dire...

The melting temperature of duplex DNA is much higher in polyanions than in non-ionic polymers with similar ionic strength, suggesting an additional electrostatic contribution on top of the excluded volume effect.