In this paper, porous metal−organic frameworks (MIL-53 [CrIII (OH).{O2C-C6H4-CO2}.{HO2C-C6H4-CO2H}x]) were hydrothermally synthesized and, then, a hybrid composite of these synthesized porous metal−organic frameworks (MOF) with acid-treated multi-walled carbon nanotubes (MWCNTs) was prepared. The materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunau...

cloud point extraction and spectrophotometric determination of trace quantities of cadmium in some vegetables have been developed. the research area for vegetables analysis was near to the zarin shahr where the soil received heavy metals from the esfahan steel company. cloud point extraction used dithizone as complexing agent and non ionic surfactant triton-x114 as micellar phase. several impor...

a simple, sensitive and rapid method for determination of trace amounts of nitrite ion in real samples is reported. the reaction is initiated by adding known volumes of a nitrite ion solution of identified concentration to acidic solutions of thionine which causes decolorizaiton of reagent with time. the absorbance changes is then monitored spectrophotometrically at lmax = 602nm at 25 °c. calib...

a column of alumina modified with sodium dodecyl sulfate (sds) and dimethylglyoxime (dmg) was prepared for the preconcentration of trace nickel from water samples for flame atomic absorption spectrometry (faas) determinations. under optimized conditions (ph=7.0; flow rate: 20 mlmin-1) nickel was retained on the column. the nickel collected on the column was eluted with 5 ml of 1 m nitric acid. ...

a partial least squares (pls) calibration model was developed for the simultaneous spectrophotometricdetermination of pb (ιι), cu (ιι) and ni (ιι) using xylenol orange as a chromogenic reagent. the parameterscontrolling behavior of the system were investigated and optimum conditions were selected. the calibrationgraphs were linear in the ranges of 0.0–9.091, 0.0–2.719 and 0.0–2.381 ppm for lead...

a simple, accurate and precise hptlc- densitometry method for the simultaneousdetermination of abacavir, lamivudine and zidovudine in pharmaceutical tablet has beendeveloped. separation of tablet components was performed on aluminum backed hptlc plates(silica gel 60 f254 20×20 cm with 0.2 mm thickness, camag, muttenz, switzerland ) usingmethanol : chloroform : acetonitrile (4 : 8 : 3 v/v). good...