An analytical ultrasound-assisted extraction (UAE) method has been optimized and validated for the rapid extraction of stilbenes from grape canes. The influence of sample pre-treatment (oven or freeze-drying) and several extraction variables (solvent, sample-solvent ratio and extraction time between others) on the extraction process were analyzed. The new method allowed the main stilbenes in gr...

A gel is an aggregate of polymers and solvent molecules. The polymers crosslink into a three-dimensional network by strong chemical bonds, and enable the gel to retain its shape after a large deformation. The solvent molecules, however, interact among themselves and with the network by weak physical bonds, and enable the gel to be a conduit of mass transport. The time-dependent concurrent proce...

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...

in this research, a rapid, reliable and selective dispersive liquid-liquid microextraction (dllme) followed by direct injection of microdroplet to graphite furnace atomic absorption spectrometry (gf-aas) method for the determination of ultra-trace amounts of ag(i) was developed. effect of the important experimental parameters on the extraction efficiency of ag(i) was investigated using response...

a simple and efficient method for the synthesis of quinolines and polycyclic quinolines using li+ modified nanoporous na+-montmorillonite is described. this new nanocatalyst proceeds via friedlander annulation under solvent-free conditions. it describes our observations about a trend of catalytic activity of lithium cation in nanoporous na+-montmorillonite. in this study, several types of 1,3-d...

A reliable method for the determination of bulk-solvent model parameters and an overall anisotropic scale factor is of increasing importance as structure determination becomes more automated. Current protocols require the manual inspection of refinement results in order to detect errors in the calculation of these parameters. Here, a robust method for determining bulk-solvent and anisotropic sc...

In this study, we prepared all-trans retinoic acid (ATRA)-encapsulated, surfactant-free, PLGA nanoparticles. The nanoparticles were formed by nanoprecipitation process, after which the solvent was removed by solvent evaporation or dialysis method. When a nanoparticle was prepared by the nanoprecipitation solvent evaporation method, the nanoparticles were bigger than the nanoparticles of the nan...

A convenient synthetic method for the synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetra substituted imidazole derivatives, has been developed via one-pot condensation reaction in solvent-free condition when aldehyde, ammonium acetate/amine, and 1,2-diketone are reacted using 0.8 mol% of NP-LaMnO3 at 80 °C under solvent free conditions. Catalyst could be recovered and reused in five reaction c...

The present paper reviews various pathways that will lead to reduction of organic solvent usage in pesticide residue analysis. Considerable reduction of solvent consumption can be achieved by miniaturizing the scale of sample extraction and cleanup and by simplifying the analytical procedures. Adoption of new analytical techniques, such as solid-phase microextraction and supercritical fluid ext...