In this research, Quantum-mechanical calculations were performed at the HF method with the 6-31+G*basis set and at the B3LYP method with the 6-31+G* basis set in the gas phase and five solvents such as water, DMSO, methanol, ethanol and dichloromethane at six temperatures. According to these theoretical results of IR, we extracted thermo chemical parameters such as enthalpy (∆H Kcal/mol), Gibbs...

Several simulation methods are currently in use to study peptide and protein folding. They can be classified in three groups depending on how the solvent is treated. At the simplest level, the solvent is ignored. At a second level, solvent effects are implicitly represented in the atomic interaction function. At the third level, solvent degrees of freedom are treated explicitly. We have perform...

a series of schiff bases of ni(ii) and cu(ii) using acetylacetone (acac), salicylaldehyde (sal), ethylenediamine (en), and o-phenylendiarnine (dabe) were prepared and characterized. the electronic spectra of some copper chelates in various organic solvents depend strongly on the solvent used and the d-d band of cu(ii) shifts to red with the increase of the donor number (dn) of solvent. the colo...

Pretreatment is very important for the efficient production of value-added products from lignocellulosic biomass. However, traditional pretreatment methods have several disadvantages, including low efficiency and high pollution. This article gives an overview on the applications of ionic liquids (ILs) and IL-based solvent systems in the pretreatment of lignocellulosic biomass. It is divided int...

Two 5-acyl-2-dimethylaminonaphthalene derivatives, one with a propionyl group and the other with a fused cyclohexanone ring, are investigated as sensors of H-bond-donating ability in protic solvents of low solvent acidity. Their fluorescence is highly quenched in protic solvents, and the quenching order of magnitude is linearly related to the H-bond-donating ability of the solvent as quantified...

In this research, Quantum-mechanical calculations were performed at the HF method with the 6-31+G*basis set and at the B3LYP method with the 6-31+G* basis set in the gas phase and five solvents such as water, DMSO, methanol, ethanol and dichloromethane at six temperatures. According to these theoretical results of IR, we extracted thermo chemical parameters such as enthalpy (∆H Kcal/mol), Gibbs...

a comparative study of ultrasound-assisted extraction (uae) and hydro-distillation was performed for fast extraction of estragole from tarragon (artemisia dracunculus l.) dried leaves. several influential parameters of the uae procedure in the extraction of estragole (type of solvent, extraction cycles, solvent to material ratio, irradiation time and particle size) were investigated and optimiz...

There is a great demand for development of catalyst systems that are not only efficient and highly enantioselective but are also environmentally benign. Herein we report investigations into the catalytic asymmetric addition of alkyl and functionalized alkyl groups to ketones under highly concentrated and solvent-free conditions. In comparison with standard reaction conditions employing toluene ...