Papers by majid farahmandjou
Ceramic Research Institute, 2015
Nano-porous alumina ceramics were fabricated using a simple and new sol-gel method. Aluminium oxi... more Nano-porous alumina ceramics were fabricated using a simple and new sol-gel method. Aluminium oxide (Al2O3) nanoporous templates were synthesized by iron (III) nitrate 9-hydrate and aluminium isopropoxide as precursor. The samples were characterized by high resolution transmission electron microscopy (HRTEM), field effect scanning electron microscopy (FESEM), X-ray diffraction (XRD), fourier transform infrared spectroscopy (FTIR) and UV-Vis spectrophotometer. XRD technique was used to identify α-alumina and γ-alumina. XRD pattern exhibited gamma-Al2O3 to alphaAl2O3 structural phase transition in nanoporous. The particle size of spherical as-prepared Al2O3 was measured around 20 nm by direct HRTEM observation. The surface morphological studies depicted the samples changed from sphere-like shaped to sponge-like pore structure by increasing annealing temperature. The sharp peaks in FTIR spectrum determined the purity of Al2O3 nanoparticles and absorbance peak of UV-Vis spectrum showed the small bandgap energy of 2.61 ev.
Journal of Nanostructures, 2014
Iron oxide (Fe2O3) is widely used as a catalyst, pigment and gas sensitive material. In this art... more Iron oxide (Fe2O3) is widely used as a catalyst, pigment and gas sensitive material. In this article, α-Fe2O3 nano-rods were first synthesized via a simple chemical method using iron(III) nitrate 9- hydrate (Fe(NO3)3.9H2O) as precursor. XRD pattern showed that the iron oxide nanoparticles exhibited alpha-Fe2O3 (hematite) structure in nanocrystals. The single-phase α- Fe2O3 nano-rods were prepared when the samples calcined at 500 °C. The smallest particle size was found to be 18 nm in diameter. The SEM studies depicted rod-like shaped particles with formation of clusters by increasing annealing temperature. The sharp peaks in FTIR spectrum determined the purity of Fe2O3 nanoparticles and absorbance peak of UV-Vis spectrum showed the small bandgap energy of 2.77 ev. The VSM result showed a coercive field and saturation magnetism around 90 G and 9.95 emu/g, respectively.
Current Physical Chemistry, 2021
Background: The synthesis of Fe2O3/ZnO nanocomposites has gained wide acceptance in recent years ... more Background: The synthesis of Fe2O3/ZnO nanocomposites has gained wide acceptance in recent years due to its magnetic, photoluminescence and catalytic properties, and as an active element in gas sensors. This type of composite particle has potential biological and biomedical applications such as the detection of cancer cells, bacteria and viruses, and for magnetic separation. Objective: In the present study, first we synthesized the Fe2O3/ZnO nanoparticles, and then the structural, optical and surface morphological properties were investigated by XRD, HRTEM, FESEM, XRF and FTIR analyses. Methods: Fe2O3-ZnO nanoparticles were fabricated by a solgel synthesis method by combining iron chloride hexahydrate and zinc sulfate heptahydrate. In the beginning, 2g of Polyvinylpyrrolidone (PVP) stabilizer was dissolved in 100 mL deionized water and then 5 g FeCl3 was added to the solution with stirring at room temperature. Then 5g of ZnSO4 was added to the solution and synthesis temperature was ...
Chinese Journal of Physics, 2015
Ferric oxide (Fe2O3) nanoparticles were synthesized by using iron chloride hexahydrate (FeCl3· 6H... more Ferric oxide (Fe2O3) nanoparticles were synthesized by using iron chloride hexahydrate (FeCl3· 6H2O) as the precursor and polyvinylpyrrolydon (PVP) as the surfactant and polymer agent. The samples were characterized by high resolution transmission electron microscopy (HRTEM), field effect scanning electron microscopy (FESEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), a UV-Vis spectrophotometer, and a vibration sampling magnetometer (VSM). The XRD pattern showed that the iron oxide nanoparticles exhibited a gamma-Fe2O3 (maghemite) to alpha-Fe2O3 (hematite) structural phase transition in the nanocrystals. The particle size of the as-prepared sample was around 20 nm and the annealed sample was around 48 nm in diameter, as estimated by the XRD technique and direct HRTEM observation. The surface morphological studies from SEM depicted sphere-like shaped to rod-like shaped particles with the formation of clusters by increasing the annealing temperature. The ...
Structural and morphological properties of vanadium oxides (V 2 O 5 ) nanoparticles have been stu... more Structural and morphological properties of vanadium oxides (V 2 O 5 ) nanoparticles have been studied. V 2 O 5 nanoparticles were synthesized using a simple chemical method by sodium metavanadate as precursor and Cetyltrimethylammonium bromide (CTAB) as surfactant. The samples were characterized by high resolution transmission electron microscopy (HRTEM), field effect scanning electron microscopy (FESEM) and X-ray diffraction (XRD). As there are many forms of vanadium oxides produced during this process, x-ray diffraction (XRD) technique was used to identify V 2 O 5 phase. The size of as-prepared nanoparticles was around 5 nm as estimated by HRTEM technique and average diameter of annealed one was around 9 nm. The surface morphological studies from SEM depicted the formation of nanorods after annealing process. The effect of CTAB surfactant on the particle morphology was also studied and the results show that the size of particles reduce to 10 nm in presence of CTAB surfactant. FTIR...
Physical Chemistry Research, 2016
Cobalt ferrite (CoFe2O4) nanorods were synthesized by iron chloride (FeCl3.6H2O) and cobalt sulfa... more Cobalt ferrite (CoFe2O4) nanorods were synthesized by iron chloride (FeCl3.6H2O) and cobalt sulfate hexahydrate (CoSO4.7H2O) as precursor in the presence of ethylene glycol agent and poly vinyl pyrrolidone (PVP) surfactant. The samples were characterized to identify the physical properties. XRD pattern of cobalt ferrite samples showed the structure of body center cubic (bcc) structure. The diameter of as-prepared samples was determined about 20 nm and annealed one was about 30 and 50 nm in diameter at 500 °C and 1100 °C, respectively. The TEM studies showed that the particles change from rod shaped to sphere-liked shaped particles by increasing annealing temperature. Peaks in the FTIRspectrum determined the element of Fe-Co nanoparticles. EDS shows peaks of iron and cobalt with fewer impurities in prepared samples and Fe/Co ratio was also decreased with increasing annealing temperature. The result of magnetic measurements showed saturation magnetization around 59.5 emu g-1 for annea...
Iranian Journal of Chemistry & Chemical Engineering-international English Edition, 2020
In this study, iron doped alumina (Fe-Al2O3) nanoparticles containing 2 mol%, 4 mol%, and 6 mol% ... more In this study, iron doped alumina (Fe-Al2O3) nanoparticles containing 2 mol%, 4 mol%, and 6 mol% iron impurities were fabricated by co-precipitation method in the presence of Al2(SO4)3.9H2O and Fe2(SO4)3.9H2O precursors. The prepared nanoparticles were heated at 1000 oC to study their physicochemical properties. The XRD results pointed out the multiphase for the samples. The morphological results revealed that the uniformity increased by increasing iron atoms rate. TEM analysis revealed that the particle with a size of 40 nm was obtained for 4% of the sample. The results of FTIR analysis indicated that when the 2% impurity increases the AlO4 tetrahedral and AlO6 octahedral vibrational bond grows.
International Journal of Bio-Inorganic Hybrid Nanomaterials, 2015
In the past decade, magnetic nanomaterials have attracted much attention due to their physical pr... more In the past decade, magnetic nanomaterials have attracted much attention due to their physical properties and technological applications. In this work, α-Fe2O3 nanoparticles were first synthesized via a simple co-precipitation method using iron chloride hexahydrate (FeCl3.6H2O) as precursor and ammonia solution as precipitator. The samples were then characterized by high resolution transmission electron microscopy (HRTEM), field effect scanning electron microscopy (FESEM), X-ray diffraction (XRD) and electron dispersive spectroscopy (EDS) Fourier transform infrared spectroscopy (FTIR) and UV-Vis spectrophotometer. XRD pattern showed that the iron oxide nanoparticles exhibited alpha-Fe2O3 (hematite) structure innanocrystals. The α- Fe2O3 nano-powders with uniform size were prepared when the samples calcined at 500 °C, and the lowest particle size was found to be 30 nm by XRD technique and direct HRTEM observation. The surface morphological studies from SEM depicted sphere-like shaped...
Recently, magnetic nanomaterials have been used in a wide range of applications such as medicine ... more Recently, magnetic nanomaterials have been used in a wide range of applications such as medicine and electronics. In this research, rod-like shaped cobalt oxide magnetic nanoparticles (Co3O4) were synthesized by a simple co-precipitation method using cobalt chloride as a precursor and sodium borohydride (NaBH4) as reducing agent. Their structural and surface morphological properties were characterized by high-resolution transmission electron microscopy (HRTEM), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD) and vibration sampling magnetometer with (VSM). XRD measurement exhibited the structure of Co3O4 nanocrystals for annealed samples. The TEM results showed the cobalt oxide nanoparticles with good uniformity in the range size of 10-40 nm. The SEM images revealed that the particles changed from spherical shape to rod-like shape with increasing temperature. Magnetic measurements showed the coercive field of around 84.5G and saturation magnetization of a...
Structural Chemistry, 2021
The research aims at investigating a nano-QSPR model applying SMILES and quasi-SMILES features fo... more The research aims at investigating a nano-QSPR model applying SMILES and quasi-SMILES features for the bandgap prediction of MO-NPs. The broad set of 198 combinations of SMILES and quasi-SMILES of MO-NPs is divided into training and validation sets six times. The statistical characteristics of the QSPR models were reported based on the index of the ideality correlation target function and the Monte Carlo optimization. The significance of eclectic features of the increase/decrease of the bandgap has been interpreted mechanistically. The good statistical quality of the models shows the models can be used to assess the reliability of experimental data of the bandgap for MO-NPs.
Journal of Electronic Materials, 2019
Pure titanium dioxide (TiO 2) and Ce-doped TiO 2 nanoparticles (NPs) were synthesized with the di... more Pure titanium dioxide (TiO 2) and Ce-doped TiO 2 nanoparticles (NPs) were synthesized with the different dopant percentages of 2%, 4%, 6%, 8%, and 10% by using titanium tetrachloride (TiCl 4) and cerium chloride (CeCl 3) precursors, pure water as a solvent, and hydrochloric acid (HCl) as the hydrolysis reactor in the presence of ethylene glycol (C 4 H 10 O 3) stabilizer through the solgel method. The morphological, structural, optical and electronic properties of the NPs were investigated via x-ray diffraction (XRD) analysis, field emission scanning electron microscopy, transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), diffuse reflectance spectroscopy (DRS) and photoluminescence spectroscopy (PL). From the XRD analysis, it was found that the structure of the Ce-TiO 2 NPs remained unchanged in the tetragonal state and anatase phase by increasing dopant, while the size of the nanocrystals (29 nm) in the pure state decreased down to 25 nm by increasing dopant up to 6%. The apparent pseudo-spherical shape and diameter of about 26 nm were obtained for the impure NPs through TEM. The UV-DRS analysis indicated the wide-band gap formation of the NPs through the water-based sol-gel method. As Ce increased, the band gap was enhanced from 5.02 eV for the pure TiO 2 NPs up to 5.46 eV for the NPs of 10% dopant. The wide band gap created in these NPs allowed them to be used with an optimum absorption in the ultraviolet (UV) light applications. The results of FTIR analysis showed that the absorption peak of 508 cm À1 was related to the vibrational bond of Ti-O-Ce in the pure state, which changed towards the frequencies of 498 cm À1 , 513 cm À1 , 490 cm À1 , 492 cm À1 and 469 cm À1 for the Ce dopant concentrations of 2%, 4%, 6%, 8%, and 10% entering into the TiO 2 matrix, respectively. Finally, the results of the PL analysis revealed that the maximum energy-band interaction of TiO 2 with Ce was created at 426 nm with a dopant of 6%.
Journal of Evolution of Medical and Dental Sciences, 2019
BACKGROUND Pain perception in young children did not receive much attention as there are concerns... more BACKGROUND Pain perception in young children did not receive much attention as there are concerns regarding the safety of administering potent opiates and sedatives. Moreover, we often consider that it is natural for children to cry in such situations and young children won't complain about pain. Midazolam is a short-acting benzodiazepine with rapid onset of action and is one of the most widely used sedatives in intensive care unit. The intranasal route avoids the need for intravenous access, avoids the pain of the parenteral injection, and is easily accessible for drug administration. The aim of this study is to compare the safety and efficacy of intranasal midazolam against intravenous midazolam for paediatric procedural sedation. MATERIALS AND METHODS This prospective study was conducted in Paediatric ward, IMCH, Medical College, Kozhikode from June 2015 to May 2016. 128 children between 3 and 12 years requiring a diagnostic lumbar puncture were included. They were divided into 2 groups A (Intranasal) and B (Intravenous) by random allocation. Statistical analysis was performed using statistical package for social sciences 16.0 (SPSS 16.0) statistics analysing software. RESULTS The deviation of heart rate from baseline during procedure is significantly more in intravenous group with t (116.345)= 2.354, p= 0.020 & also the deviation of heart rate from baseline at the end of procedure was significantly higher among intravenous group with t (103.974)= 4.593, p= 0.000. The deviation of diastolic blood pressure during procedure from baseline is significantly higher among the intravenous group with t (102.521)= 4.535, p= 0.000 & also the deviation of diastolic blood pressure from baseline to the end of procedure was significantly higher among the intravenous group with t (126)= 4.819, p= 0.000. The sedation achieved during the procedure is comparable between the two groups with a p value of 0.225. The intranasal group took longer time to achieve adequate sedation as well as for recovery. But there were no serious adverse effects. CONCLUSION Intranasal midazolam is safe and effective for paediatric procedural sedation and is associated with lesser variability in heart rate and blood pressure in comparison with intravenous midazolam.
Materials Engineering Research, 2019
Titanium dioxide nanoparticles (TiO 2) have been extensively investigated because of its high che... more Titanium dioxide nanoparticles (TiO 2) have been extensively investigated because of its high chemical sustainability, optic properties, and adaptation to the environment. These studies include applications in heterogeneous catalysts, solar cells, coating technology, and electrical devices. TiO 2 particles in the nanometer scale can remove limitations, such as the absorbance of organic materials, because of a high surface area to volume ratio. Titanium dioxide nanoparticles, were synthesized using a simple wet chemical method. Their physico-chemical properties were characterized by transmission electron microscopy (TEM), scanning electron microscopy (SEM) and X-ray diffraction (XRD) analyses. The TEM results showed that the mean size of assynthesized TiO 2 was 5 nm with high crystalline anatase phase. The SEM observations revealed that the size of nanoparticles increased with annealing temperature and the morphology of the particles changed to the spherical shape. The crystal structure of the nanoparticles before and after annealing was done by XRD analysis. The rutile phase was formed after heat treatment at 600 o C for 3 hours.
Materials Research Express, 2018
Nanoparticles (NPs) of pure titanium dioxide (TiO2) and impure titanium dioxide (Ce-doped TiO2) w... more Nanoparticles (NPs) of pure titanium dioxide (TiO2) and impure titanium dioxide (Ce-doped TiO2) were made with impurity percentages of 1%, 2%, 3%, 4%, and 6% by the sol-gel technique, with a new precursor of tetratitaniumisopropoxide (TTIP) and cerium chloride (CeCl3), acetic acid as a catalyst, and ethylene glycol as stabilizer in an ethanol solvent. The morphological, structural, and optical properties of NPs were examined. An XRD analysis showed that the TiO2 NPs had a tetragonal structure as the sample structures did not change as a result of the insertion cerium impurity into the TiO2 lattice. The structural results have also shown that the size of NPs is reduced by an increase in Ce impurities as the pure size of 38 nm reduces to 21.4 nm because of 6% impurity. A FESEM analysis showed that an increase in the impurity percentage reduces NPs uniformity because of its reducing size. The apparent shape and mean diameter of NPs obtained by TEM analysis was 25.2 nm for with 3% impurities in a quasi-spherical form. The UV-DRS optical analysis results showed that the band gap increases due to an increase in the Ce impurity percentage from 2.75 eV for pure TiO2 NPs to 3.09 eV for NPs with 6% impurities. In addition, a photoluminescence analysis showed that the intensity increased following an increase in impurities because of a band-gap increase.
International Journal of Applied Ceramic Technology, 2018
Pure and Fe-doped Al 2 O 3 nanoparticles (NPs) were synthesized with different iron doping percen... more Pure and Fe-doped Al 2 O 3 nanoparticles (NPs) were synthesized with different iron doping percentage of 1, 3, and 5 mol% employing sol gel technique with AlCl 3 , FeCl 3 as well as ethylene glycol (EG) and Polyvinylpyrrolidone (PVP) stabilizers as precursors. The XRD results indicated that the hexagonal structure of Fe/Al 2 O 3 nanocomposite with alpha phase was formed by the substitution of Fe 3+ ions in the alumina network. The sizes of the NPs obtained for the pure samples and doped samples at percentage dopant of 5% were 35 nm and 28 nm, respectively. The results of FTIR optical analysis showed the vibrational bond at the wavelength of 448 cm-1 , indicating the Al-O band in the sample. The UV-DRS analysis showed that the energy band gap for the pure NPs was 4 eV, but with increase in iron dopant up to 5%, it decreased to 3.42 eV. In addition, the results of photoluminescence (PL) analysis Accepted Article This article is protected by copyright. All rights reserved. demonstrated that with increase in doping percentage, the PL intensity diminished. VSM magnetic analysis showed that with increase in iron dopant, the ferromagnetic state emerged in the NPs at saturation magnetism of 0.136 emu/g. Finally, photocatalytic experimental results demonstrated that 5% Fe-doped Al 2 O 3 NPs effectively degrade MB approximately 53%.
Chinese Physics Letters, 2018
Journal of Electronic Materials, 2018
Fe-doped TiO 2 powders were synthesized by the sol-gel method using titanium (IV) isopropoxide (T... more Fe-doped TiO 2 powders were synthesized by the sol-gel method using titanium (IV) isopropoxide (TTIP) as the starting material, ethanol as solvent, and ethylene glycol (EG) as stabilizer. These prepared samples were characterized by x-ray diffractometer (XRD), field emission scanning electron microscope (FESEM), Fourier-transform infrared (FTIR) spectroscopy, diffuse reflection spectroscopy (DRS), energy-dispersive x-ray spectroscopy (EDX), and photoluminescence (PL) analyses to study their structure, morphology, and optical properties. The particle size of Fe-doped TiO 2 was in the range of 18-39 nm and the minimum crystallite size was achieved for 4 mol.% of Fe. The XRD result of the samples that were doped with Fe showed a tetragonal structure. It also revealed the coexistence of the anatase and rutile phases, and showed that their ratio changed with various molar concentrations of Fe dopant. FTIR spectroscopy showed the presence of the Ti-O vibration band in the samples. PL analysis revealed the PL property in the UV region. Visible irradiation and the intensity of PL spectra were both reduced by doping TiO 2 with 3 mol.% of Fe as compared to the pure variety. The spectra from the DRS showed a red shift and a reduction of 2.6 eV in the band gap energy for 4 mol.% Fe-doped TiO 2. The optimum level of impurity (4 mol.%) for Fe-doped TiO 2 nanoparticles (NPs), which improve the optical and electrical properties by using new precursors and can be used in solar cells and electronic devices, was determined. The novelty of this work consists of: the Fe/TiO 2 NPs are synthesized by new precursors from sol-gel synthesis of iron and TTIP using acetic acidcatalyzed solvolysis (original idea) and the optical properties optimized with a mixture of phases (anatase/rutile) of Fe-doped TiO 2 by this facile method.
Journal of Superconductivity and Novel Magnetism, 2018
The as-prepared and annealed iron/cobalt (FeCo) magnetic nanoparticles (NPs) were obtained using ... more The as-prepared and annealed iron/cobalt (FeCo) magnetic nanoparticles (NPs) were obtained using a simple method by iron chloride hexahydrate (FeCl 3 .6H 2 O) and cobalt chloride hexahydrate (CoCl 3 .6H 2 O) as precursors and sodium borohydride (NaBH 4) agent. The samples were characterized by high-resolution transmission electron microscopy (HRTEM), field effect scanning electron microscopy (FESEM), x-ray diffraction (XRD), electron-dispersive spectroscopy (EDS), and Fourier transform infrared spectroscopy (FTIR). The XRD patterns of FeCo samples showed the body center cubic (bcc) structure with a lattice constant of 2.70Å. The SEM images showed that the particle size of the as-prepared sample was around 15 nm and the annealed sample was around 35 nm in diameter at 500 • C. It was found that by increasing annealing temperature, the size of the FeCo NPs increased to 60 nm at 1100 • C. TEM studies showed the rod-like particles for annealed sample. The sharp peaks in FTIR spectrum determined the element of FeCo NPs. EDS shows peaks of iron and cobalt with impurities in prepared samples. The result of magnetic measurements showed a good coercive field and saturation magnetization around 1158 Oe and 22 emu g −1 , respectively.
Journal of Nanomedicine Research, 2017
Vanadium oxides (V 2 O 5) nanoparticles have been prepared using a simple chemical method by sodi... more Vanadium oxides (V 2 O 5) nanoparticles have been prepared using a simple chemical method by sodium metavanadate as precursor and Cetyl trimethylammonium bromide (CTAB) as surfactant. The samples were characterized by high resolution transmission electron microscopy (HRTEM), field effect scanning electron microscopy (FESEM) and X-ray diffraction (XRD). As there are many forms of vanadium oxides produced during this process, x-ray diffraction (XRD) technique was used to identify V 2 O 5 phases. The size of as-prepared nanoparticles was around 5 nm and average diameter of annealed one was around 10 nm. The effect of CTAB surfactant on the particle morphology showed that the size of particles reduce to 10 nm in presence of CTAB surfactant. FTIR spectrum showed the presence of V-O and V-O-V stretching mode.
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Papers by majid farahmandjou