A series of CuO-ZnO-Al2O3 nanoparticles over HZSM-5 were successfully prepared using different methods of batch co-precipitation, semibatch co-precipitation and combined co-precipitation-ultrasound. Nitrates of copper, zinc and aluminum were used as precursors, while Na-ZSM-5 was employed as composite support and sodium carbonate was used as precipitant agent. The effects of preparation methods...

among the usual interpolation methods, kriging and co-kriging are frequently used in the interpolation of precipitation data as one the best linear unbiased estimators, despite these advantages, there models show smoothness representation and because they are based on regional averages of the data, they predict maximum and minimum values   lower and higher than real values respectively. therefo...

the perovskite-type oxides strontium-substituted lanthanum nickelate (lsno) were prepared by a coprecipitation method in the present of octanoic acid as surfactant. the phase composition, morphology,lattice parameters and size of nanoparticles in these materials were characterized through fourier transform infrared spectroscopy (ft-ir), x-ray diffraction (xrd), scanning electron microscopy (sem...

the kinetic of fischer-tropsch synthesis over a co-precipitated fe-ce catalyst was investigated in a fixed bed micro reactor. experimental conditions were varied as follow: reaction pressure 1-15bar, h¬¬¬2/co feed ratio of 1-3 and space velocity of 3600-5400 h-1 at the temperature range of 270-310°c. 4 models according to the langmuir-hinshelwood-hougen-watson (lhhw) type rate equation were der...

In this paper, we applied the support vector machine (SVM) to the spatial interpolation of the multi-year average annual precipitation in the Three Gorges Region basin. By combining it with the inverse distance weighting and ordinary kriging method, we constructed the SVM residual inverse distance weighting, as well as the SVM residual kriging precipitation interpolation model and compared them...

cobalt ferrite is an important magnetic material due to their large magneto-crystalline anisotropy, high cohercivity, moderate saturation magnetization and chemical stability.in this study, cobalt ferrites nanoparticles have been synthesized by the co-precipitation method and a new microemulsion route. we examined the cation occupancy in the spinel structure based on the “rietveld with energies...

a series of cuo-zno-al2o3 nanoparticles over hzsm-5 were successfully prepared using different methods of batch co-precipitation, semibatch co-precipitation and combined co-precipitation-ultrasound. nitrates of copper, zinc and aluminum were used as precursors, while na-zsm-5 was employed as composite support and sodium carbonate was used as precipitant agent. the effects of preparation methods...

In this study, magnetic iron oxide nanoparticles (Fe3O4) with the size range of 20-30 nm were prepared by the modified controlled chemical co-precipitation method from the solution of ferrous/ferric mixed salt-solution in alkaline medium. In this process polyethylene glycol was used as a surfactant to prevent the solution from agglomeration. The prepared magnetic nanoparticles were characterize...

In this study, SiO2 nanoparticles were successfully synthesized via sol-gel precipitation method and the effects of different parameters such as temperature, ethanol, ammonia and tetraethylorthosilicate (TEOS) contents based on water were investigated in a systematic way applying Taguchi experimental design method. It was found that, among all the investigated parameters, ethanol as a co-solven...

in this study, magnetic iron oxide nanoparticles (fe3o4) with the size range of 20-30 nm were prepared by the modified controlled chemical co-precipitation method from the solution of ferrous/ferric mixed salt-solution in alkaline medium. in this process polyethylene glycol was used as a surfactant to prevent the solution from agglomeration. the prepared magnetic nanoparticles were characterize...