The sal inity tolerance (precipitation phase boundary) is measured for a mixed anionic/nonionic surfactant sy s t em above the CMC. For any total surfactant concentration, the salinity tolerance is shown to increase as the percentage of nonionic surfactant in the s y s t e m is increased. A model is developed which can predict the phase houndaries for the mixed surfactant s y s t e m from the p...

Clouding phenomenon generally occurs with nonionic surfactants when the temperature of the system is raised to a certain value. This critical temperature is termed the cloud point (CP). The aqueous solutions of nonionic surfactants show complex phase behaviour including liquid-liquid phase separation at this temperature. The cloud point of aqueous surfactant solutions is influenced by the prese...

liquid protein formulations are prone to form aggregates. the effect of nonionic surfactants such as polysorbate 20 (ps 20) and n-dodecyl β-d-maltoside (ddm) on the prevention of aggregation and conformational changes of recombinant human ifnβ-1b (rhifn β_1b) was explored. polysorbate has been used in formulations of protein pharmaceuticals. there have been concerns about using ps 20 due to its...

Washing is one of the common technologies in the chlorinated organic pollution site repair, surfactant adding would help washing more chlorinated organics pollution, but it also can be dissolved in eluent with the chlorinated organic together, and increase the difficulty of the eluent treatment. In this text, three surfactants, anionic surfactant (sodium dodecyl benzene sulfonate, SDBS), cation...

This paper presents a set of surfactant-selection guidelines that can be used to design bio-based semi-synthetic metalworking fluid (MWF) microemulsions as a renewable alternative to conventional petroleum formulations. Ten surfactant classes (six anionic and four nonionic) with different head and tail structures and three vegetable base oils (canola oil, soybean oil, and a fatty acid trimethyl...

in this research, effect of bicomponent mixed surfactant was studied on drop interface coalescence phenomenon in ambient temperature. first basic chemical system was water and toluene and 0.01 gr of sodium dodecyle sulfate (sds) and the second basic system was water and toluene and 0.01 gr of cethyl trimethy amonium bromide (ctab). various weight fractions of second surfactant including 2-hepta...

Surfactant-enabled asymmetric ATA-catalyzed reductive aminations in aqueous buffered media are described, representative of the enhanced levels conversion made possible by presence a nonionic surfactant water, thereby enabling 1-pot chemoenzymatic catalysis.

It is well-known that ionic surfactant coated single-walled carbon nanotubes (SWNTs) possess higher near-infrared fluorescence (NIRF) quantum yield than nonionic polymer functionalized SWNTs. However, the influence of surface functionalization on the magnetic properties of SWNTs for T2-weighted magnetic resonance imaging (MRI) has not been reported. Here, we demonstrate that SWNTs functionalize...

Surfactant adsorption layers on polystyrene latex particles are investigated concerning their equilibrium exchange dynamics with surfactant molecules in solution. Pulsed field gradient (PFG) nuclear magnetic resonance (NMR) self-diffusion measurements of the nonionic surfactant C12(EO)5 are performed, making use of the difference of the diffusion coefficients of adsorbed and free surfactant in ...

The successful formulation of particulate dispersions is often hindered by the presence of charged species dissolved in solution. If present at high enough concentrations, these species can reduce the screening length between particles to near zero, allowing rapid coagulation and destabilization. The addition of a mixture of ionic and nonionic surfactants has been shown in a previous publicatio...