a simple and rapid microextraction procedure based on dispersive liquid-liquid microextraction (dllme) was developed for determination and speciation of trace amounts of chromium (cr) by flame atomic absorption spectrometry (faas). in the proposed approach, chloroform and methanol were used as extraction and dispersive solvents. a new schiff's base ligand, bis(2-methoxy benzaldehyde) ethylene d...

Biochar’s ability to amend and remediate agricultural soil has been a growing interest, though the energy expenses from high-temperature pyrolysis deter product’s use. Therefore, it is urgent improve efficiency while ensuring quality of produced biochar. The present study utilized three types feedstock (i.e., switchgrass, biosolid, water oak leaves) produce biochar via conventional slow microwa...

phase inversion in liquid-liquid dispersions corresponds to the transitional boundary between oil-in-aqueous dispersion and aqueous-in-oil dispersion. a theoretical model based on simple assumptions was proposed to predict phase inversion point, ambivalence region and the hysteresis effect of inversion. experimental data from the literature were used to validate the model and results were compa...

the effect of magnetic field on the liquid-liquid equilibrium of two ternary systems (water + acetic acid + butyl acetate and water + acetic acid + dimethyl succinate) at 298.15 k under atmospheric pressure was investigated. the results obtained show that the strength of the magnetic field (0.02 t) affects the solubility of acetic acid in the used organic solvents. distribution coefficients and...

the dispersive liquid–liquid microextraction (dllme) method for determination of pb +2 and cd +2 ions in the environmental water samples was combined with inductively coupled plasma-atomic emission spectrometry (icp-aes). ammonium pyrrolidine dithiocarbamate (apdc), chloroform and ethanol were used as chelating agent, extraction solvent and disperser solvent, respectively. some effective parame...

Soil degradation and the use of urban biosolid wastes to soil restoration have an economic, social-environmental health impact. Therefore, there is interest worldwide in comparison methodologies establish quality indexes (SQIs) based on physical, chemical, biological indicators soils. Considering that more than 60% territory Bajío region Mexico State Guanajuato affected by some type degradation...

separation of ten sedative- hypnotic drugs was performed by rp-hplc using mixed micellar mobile phase. effect of temperature, type and amount of organic modifier in mobile phase on efficiency (n) and asymmetry factor (b/a) showed that, the appropriate conditions for a good separation were 35°c and 7% (v/v) butanol in mobile phase.  variations of selectivity factor versus butanol concentration, ...