in the present work, the regioselectivity for a series of diels–alder reactions (4 reactions) has beenstudied using hardness, electrophilicity and polarizability of products.furthermore,thermodynamicand kinetic calculations have been done. in all results predicted pararegioisomer is more favorableregioisomerinthese investigated reactions.all calculations have been done at the dft-b3lyp/6-31g(d)...

in this study, removal of acid blue 62 from aqueous solution by mesoporous silicate mcm-41 modified by aminopropyltriethoxysilane (aptes) composite was studied. properties of synthesized composite were analyzed and confirmed by sem, edx and ftir. results show that langmuir adsorption isotherm has the best compatibility with the results of experiments. kinetic analysis using pseudo-first-order m...

In this research, at first ordinary Aloe Vera micropowder (OAMP) and its impregnated form (IAMP) as the natural sorbents were prepared and then characterized by several techniques such as Fourier transform spectrophotometry (FT-IR), Scanning electron microscopy (SEM), Elemental analysis (EA), Brunauer–Emmett–Teller and Barrett-Joyner-Halenda (BET/BJH) essay and X-ray powder diffraction (XRD). T...

Classical xerogels are robust, inexpensive and nontoxic materials with low-ordered nanoporous structures. In water streams where the pH is higher than the Point of Zero Charge, the surface of classical xerogels such as tetraethoxy orthosilan (TEOS) xerogel is negatively charged. It was assumed that a xerogel can work as a strong adsorbent for metal ions without further modification. Therefore, ...

In the present work, two asymmetric polymer membranes based on polyvinylidene fluoride (PVDF) and polyvinylpyrrolidone (PVP) with chitin and chitosan (as extractive agents) were synthesized through the phase inversion technique. The mechanisms of oriented process for the facilitated extraction of blue P3R dye across the as-prepared membranes were elucidated through different experiments. Furthe...

We describe a novel computer system directed to evaluate protein complex formation in a liquid environment. The relevant feature of the system is a potential function expressing the main thermodynamic and kinetic factors leading to protein interaction in solution. The protein interaction model expresses the interaction energy as basically composed of three forces: electrostatic (hydrogen bond),...

The knowledge of sorption processes of nonelectrolytes in solution by solid adsorbents implies the study of kinetics, equilibrium, and thermodynamic functions. However, quite frequently the equilibrium isotherms are studied by comparing them with those corresponding to the Giles et al. classification (1); these isotherms are also analyzed by fitting them to equations based on thermodynamic or k...