−Singleand bi-solute sorption and desorption of 2-chlorophenol (2-CP) and 2,4,5-trichlorophenol (2,4,5TCP) in montmorillonite modified with hexadecyltrimethyl-ammonium (HDTMA) were investigated by sequential sorption and desorption. Effect of pH on the sequential sorption and desorption was investigated. As expected by the magnitude of octanol : water partition coefficient (K ow ), both sorptio...

Recently in this laboratory the conductometric measurement of aqueous solutions Li, Na and K salt L-leucine were studied at different temperature molar concentration to investigate solute-solvent, ion-solvent interactions (solute means drug) also effect dilution was investigated. During work thermodynamic parameters (change free energy, change entropy enthalpy) investigated concentrations range...

An understanding of density fluctuations in bulk water has made significant contributions to our understanding of the hydration and interactions of idealized, purely repulsive hydrophobic solutes. To similarly inform the hydration of realistic hydrophobic solutes that have dispersive interactions with water, here we characterize water density fluctuations in the presence of attractive fields th...

An expression of unexpected simplicity is derived for the shift in optical transition energies of solute molecules in nonpolar solvents. The expression reveals a new spectroscopic rule that says: The higher the excited state of the solute, the larger the solvatochromic red shift. A puzzle formulated >50 years ago by Bayliss is solved. Bayliss, based on arguments from classical physics, assumed ...

UV free-radical polymerization techniques are often used to synthesize hydrogels for controlled release applications. Numerous techniques exist for immobilizing drugs or solutes in the gel. This work focuses on the entrapment of solute in a hydrogel by conducting a photopolymerization in the presence of the monomer and the solute. A kinetic gelation model has been developed to examine the effec...

Time-dependent Stokes shifts (TDSS) were measured for diverse polarity probes in water, heavy water, methanol, and benzonitrile, by broadband fluorescence up-conversion with 85 fs time resolution. In water the spectral dynamics is solute-independent and quantitatively described by simple dielectric continuum theory of solvation. In methanol the slower part of the TDSS is solute-dependent. A cor...

The solvation energy and entropy at infinite dilution consist of a solute-solvent term and a solvent reorganization term representing the contributions of changes in solvent structure upon solute insertion. In the standard, homogeneous treatment of solutions, changes in solvent structure are expressed through derivatives of the homogeneous pair correlation function, which are very difficult to ...

We study the effect of the organic co-solute trimethylamine N-oxide (TMAO) on the volume phase transition of microgel particles made from poly(N-isopropylacrylamide) (PNIPAM) using dynamic light scattering (DLS) and all-atom molecular dynamics (MD) simulations. The DLS measurements reveal a continuous TMAO-induced shrinking process from a coil to a globular state of PNIPAM microgel particles. A...