Journal of Nanoanalysis
Volume:5 Issue: 1, Mar 2018

organic solvents. In this study, NiFe2O4/sawdust nanocomposite was synthesized for removingoil pollutants. The oil-adsorbing nanocomposite could be easily separated from water bymagnet bar. The XRD results show tetragonal phase proving the composite formation. TheFESEM pictures successfully reveal the growth of NiFe2O4 on the sawdust template. The FTIRbands at 422 cm-1 and 615 cm-1correspond to the metal oxygen stretching band. VSM hysteresisloop proves the superparamagnetism of the composite. In addition contact angle depictshydrophobic properties of the resulted nanocomposite. More importantly, as-preparednanocomposite exhibited high oil adsorption capacity and good reusability. Our studies showeasy synthesis and fast method for oil removal from water. Facile synthesis procedure, highoil adsorption capacity, fast and simple magnetic separation and reusability of nanoadsorbentare among the benefits of these composite. This approach will open up new fields of studiesin polluted-water treatment.

In this work, the structural and elastic moduli properties of ZnFe2O4, Zn0.5Cu0.5Fe2O4, and Ni0.3Cu0.2Zn0.5Fe2O4 ferrites prepared by the citrate method have been investigated. The structuralcharacterization of the samples is evidence for a cubic structure with Fd-3m space group. TheHalder-Wagner analysis was used to study crystallite sizes and lattice strain and also stressand energy density. The cation distribution for each composition has been suggested. Theexperimental and theoretical lattice constants were found to be in good agreement with eachother confirming the agreeability of the suggested cation distribution. The force constantsfor tetrahedral and octahedral sites have been determined by infrared spectral analysis. Theincrease in force constants of ZnFe2O4 nanoparticles compared to other samples suggests theelastic properties of this sample is better than the other samples. The values of Young’s modulus,rigidity modulus, bulk modulus, Debye temperature have been determined. In addition,using the values of the compliance sij obtained from elastic stiffness constants, the values ofYoung’s modulus and Poisson’s ratio along the oriented direction have been calculated for thesamples. Consequently, we can conclude the ZnFe2O4 nanoparticles could be more useful inindustrial applications because of their elastic properties compared to other samples.

In this study, bimodal mesoporous silica, i.e. UVM-7, was synthesized and functionalized withsulfonic acid and characterized using XRD, nitrogen physisorption, SEM, TEM and acid/basetitration. The results displayed that bimodal mesopore structure was firmly formed and acidicfunctional groups were grafted on the surface of the UVM-7. The concentration of the acidicfunctional groups was determined via titration by the standard NaOH solution. At the secondstep, the adsorption of methylene blue from aqueous solutions onto UVM-7 and UVM-7/SO3H was investigated. The effect of PH, temperature, dye concentration, salt concentrationand contact time on the adsorption of methylene blue was studied. The adsorption equilibriumisotherms were well fitted to Langmuir rather than Freundlich model. Methylene blueadsorption on UVM-7 increases with increasing the temperature and PH, which indicatesthat the process is endothermic. Maximum adsorption capacity of methylene blue by UVM-7and UVM-7/SO3H were 107.5 mg/g and 129.9 mg/g, respectively. The adsorption kinetics ofmethylene blue for both UVM-7 and UVM-SO3H were pseudo-second order and well fitted toLangmuir model.

Thermal and antimicrobial properties of hybrid synthesized compounds were evaluated in thepresent study. Hybrid structures were synthesized via two main organic and inorganic components,namely: 2-Mercaptobenzothiazole (MBT) and sodium Montmorillonite clay (Na+-MMT). The synthesis process took place in a direct reaction, intercalation; and the resultingmaterial was characterized. Results of scanning electron microscope (SEM), Energy dispersiveX-ray spectroscopy (EDS), transmission electron microscope (TEM), and small-angle X-ray scattering(SAXS) and Fourier transform infrared spectroscopy (FTIR) confirmed MBT penetrationof particles into the inner space of the clay layers and interaction between the two organicand inorganic phases. Also, thermal properties of the resulting compounds were evaluated bythermo gravimetric analysis (TGA) and differential thermalgravimetric (DTG). It was found thatwhile MBT sample had relatively low degradation temperature (about 250°C), the MBT-modifiedclay compound showed superior thermal stability, and in high temperatures, less weightloss as compared to MBT. Antimicrobial properties of the hybrid nano compound against fivetypes of bacteria, two types of fungus and one type of yeast were examined using well diffusionagar method and minimum inhibitory concentration (MIC). The diameter of inhibitionzone was measured and their antimicrobial potential was compared with two common antibiotics:gentamicin and rifampin. The concentration of about 1000 μg/mL of MBT-MMT showedantibacterial performance equal to 250 μg/mL of rifampin. Also, 1000 μg/mL of this materialwas required to inhibit the growth of important bacteria.

Density functional theory calculations were performed to investigate vitamin C interaction withN-doped TiO2 anatase nanoparticles. The adsorption of vitamin C on the energy favorable fivefoldcoordinated titanium sites was investigated. Various adsorption geometries of vitamin C towardsthe nanoparticle were examined. Since the adsorption energies of N-doped nanoparticles are higherthan those of undoped ones, the N-doped TiO2 nanoparticles can interact with vitamin C moleculemore strongly. Besides, adsorption on the pristine nanoparticle is less favorable, whereas on theN-doped one, the adsorption process is more energy favorable. The electronic structure analysis wasperformed in view of the density of states and molecular orbitals of the considered nanoparticles withthe adsorbed vitamin C molecule. The significant overlaps between the PDOS spectra of the oxygenatom of vitamin C molecule and titanium atom of TiO2 confirm the chemisorption of vitamin C onthe TiO2 nanoparticle. After the adsorption, the electronic densities in the HOMOs of the adsorptionsystems were mainly distributed over the vitamin C molecule, while the LUMOs were dominant atthe TiO2 nanoparticle. Our calculations shed light on understanding the interaction between vitamin Cand TiO2 nanoparticles, which provides an efficient outline for future experimental studies.

In this work, various 3-cyano-4-aryl-4H-pyran derivatives were prepared efficiently through a one-pot,multicomponent synthesis between aromatic aldehyde, malononitrile and acetophenone derivativesor ethyl acetoacetate using Fe3O4/EDTA magnetic nanocatalyst and ethanol as solvent. The reactionswere completed at room temperature in 10 min using 5 mg of catalyst and 2 mL of solvent to prepare1 mmol of the product. The employed catalyst has consisted of magnetite nanoparticles core, whichcoated with EDTA to modify its surface and prevent the aggregation. In addition, the catalytic abilitiesof different deep eutectic solvents (DESs) such as choline chloride/tin (II) chloride, choline chloride/zinc chloride and choline chloride/urea were compared with the nanomagnetic catalyst via thissynthesis. The nanomagnetic catalyst showed higher ability in comparison with various DESs for thetitle reaction. The employed nanomagnetic catalyst has been recycled 4 times without important lossof its activity which shows its high efficiency and small leaching.

Microencapsulation is a process in which solid, liquid or gas components are covered with a septum.The present study has focused on the effect of stirring to produce ferric saccharide capsules withalginate coating applying the coacervation method so that we can obtain the best capsules forfortification of hydrated and dehydrated food products. At first, three methods, including stirrer,ultra-sonic and sonic bath were compared in order to select the best way of stirring. The experimentresults showed that turning was provided by the stirrer method resulted in capsulation with sphericalmorphology and uniform distribution of surface. In this case the other factors such as the alginateconcentration and calcium salt concentration were investigated. After studying the various conditions,it is suggested that the best Capsules were formed in alginate 3% at 500 rpm with concentration ofcalcium chloride salt 1M. The resulted capsules by this method had a high efficiency and were morestable in hydrated and dehydrated food ingredients network for a long time.

Nano powders Eu3+ and Nd3+ - doped Sr2Nb2O7 were prepared by a low temperature hydrothermalmethod at 120 ºC for 48 h followed by annealing at 400 ᵒC for 3 h among Sr(NO3)2and Nb2O5, Eu2O3 and Nd2O3 raw materials at stoichiometric 1:1 Sr:Nb molar ratio. Characterizationof the synthesized materials was performed by X-ray powder diffraction (XRPD)technique. FullProf program employing profile matching with constant scale factors was employedfor structural analysis. The results showed that the patterns had a main Sr2Nb2O7 orthorhombiccrystal structure with space group . FESEM images showed that the synthesizednanomaterials had flower morphologies. Ultraviolet-visible spectra analysis showed that thesynthesized Eu3+ and Nd3+ - doped Sr2Nb2O7 nanomaterials had light absorption in the ultravioletlight region. The direct optical band gap energies obtained from UV-Vis absorption spectrawere 3.45, 3.50 and 3.80 eV for pure Sr2Nb2O7, S2 and S4, respectively. The catalytic activity ofthe obtained materials in the one-pot synthesis of the heterocyclic compounds 3,4-dihydropyrimidin-2(1H)-ones (DHPMs) in Biginelli reaction is investigated. The optimized 0.03 g of thecatalyst, 95 ºC reaction temperature, and 60 min reaction time are used for the other Biginellireactions in this work.