Journal of Dispersion Science and Technology, Jul 25, 2014
ABSTRACT Froth flotation was employed for quantitative separation of graphene oxide nanoribbon (G... more ABSTRACT Froth flotation was employed for quantitative separation of graphene oxide nanoribbon (GONR) from its solution. The effects of GONR concentration, pH, and cetyltrimethyl ammonium bromide (CTAB) concentration on GONR separation were studied through a Box–Behnken experimental design method. F value of 176.47, coefficient of determination of 0.9969, adjusted R2 of 0.9912, and coefficient of variation of 4.09%, explored by means of analysis of variance, implied the satisfactory adjustment of the obtained quadratic model. The results indicated that low GONR and high CTAB concentration at low pH were ideal for maximum separation by flotation.
In the present study, silver nanoparticles were synthesized by decomposition of AgNO3 via gelcast... more In the present study, silver nanoparticles were synthesized by decomposition of AgNO3 via gelcasting. Methacrylamide was used as a low toxic monomer for gel formation. Effect of monomer content (MAM), cross-linker to monomer ratio (MBAM/MAM), silver salt to monomer ratio (AgNO3/MAM), duration of calcination, and temperature of calcination were investigated to optimize the size of nanoparticles. Taguchi method was applied to study the effect of gelcasting parameters on the size of silver nanoparticles. Mentioned parameters were surveyed at four levels and based on the Taguchi method 16 experiments were carried out. Silver nanoparticles were characterized, and average particle sizes were measured by SEM analysis. By using the signal to noise ratio (S/N) analysis of the results, it is revealed that monomer content is the most effective parameter on size of particles. Also, optimal values of monomer content, cross-linker to monomer ratio, silver salt to monomer ratio, duration of calcin...
International Journal of NanoScience and Nanotechnology, 2018
Nickel-molybdenum oxidebimetallic nanoparticles were synthesized in ethylene glycol using the mic... more Nickel-molybdenum oxidebimetallic nanoparticles were synthesized in ethylene glycol using the microwave irradiation technique. According to the results, successive reduction of nickel and molybdenum ions, followed by thermal treatment of obtained nanoparticles led to formation of core-shell structured nickel-molybdenum oxide nanoparticles. According to the results, the thickness of the shell and core were 5 and 40 nm, respectively. The structure and composition of nanoparticles were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), UV-vis spectroscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS).
Advances in environmental science and technology, 2018
A straightforward procedure to synthesize keratin nanoparticles (KNP) from chicken feathers was i... more A straightforward procedure to synthesize keratin nanoparticles (KNP) from chicken feathers was introduced. The characterization of the synthesized nanoparticles was done using Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD) patterns and transmission electron microscopy (TEM). The FTIR analysis revealed no significant chemical change after the nanoparticle synthesis. TEM imaging indicated the synthesis of KNPs with a spherical morphology and mean size of 42 nm. The DLS results indicated that the synthesized KNPs were stable in aqueous media by having a zetapotential of lower than -30 mV. The produced KNPs were then evaluated for the biosorption of Cu (II) from aqueous solutions. The analyzed adsorption isotherm data revealed the change from a Redlich-Peterson isotherm to a Langmuir one by increasing the biosorbent dosage, which could be attributed to the more prepared adsorption sites. The experiments of the effect of the bioso...
A major portion of BaSO4 is used as drilling fluid additives in the presence of some biopolymers ... more A major portion of BaSO4 is used as drilling fluid additives in the presence of some biopolymers such as starch and PAC (Polyanionic Cellulose) as filtration control and viscosifier. BaSO4 nanoparticle was synthesized in the presence of these applicable polymers with precipitation method by using BaS produced from carbothermal method and Na2SO4. Synthesized nanoparticles size and morphology were analyzed using DLS (Dynamic Light Scattering) and FESEM (Field Emission Scanning Electron Microscope). It can be concluded that, nanoparticles size have inverse proportion with polymer concentration. Also nanoparticles have smaller size in the presence of PAC with longer functional group than starch and prevent chemical reaction due to steric hindrance. If pH increases from 7 to 11, nanoparticles in starch had minimum size in pH=9 and various pH didn’t have noticeable effect on size with PAC. In kinetic study, conductometer is used to detect induction time in different Na2SO4 concentrations ...
Research subject: The use of nanoparticles, especially nanoantibiotics, increases their efficacy.... more Research subject: The use of nanoparticles, especially nanoantibiotics, increases their efficacy. More uniform release of antibiotics is one of the benefits of their nano size. They can be made using ointment or banderol to be absorbed through the skin to the infection, thereby reducing its side effects. Amoxicillin is one of the most widely used antibiotics in the world which can prevent the use of other stronger antibiotics, provided that its efficacy is promoted in the form of nanoparticles. Determining the mechanism of nanoparticle formation of this drug is an important factor for its commercial production. Research approach: The purpose of this study was to determine the nucleation mechanism and induction time of crystallization of amoxicillin nanoparticles in the presence of surface active agents ‘CTAB’ and ‘SDS’. Therefore, the effect of amoxicillin concentration and stabilizing agent concentration on the crystallization process was investigated. In this project, a combinatio...
The comparative sorption studies were carried out to investigate the performance of keratin nanop... more The comparative sorption studies were carried out to investigate the performance of keratin nanoparticles (KNPs) and magnetic KNPs (MKNPs) for Zn(II) uptake. MKNPs showed remarkably higher Zn(II) removal due to the lower keratin weight percent in its structure (8.4%). MKNPs revealed relatively uniform Zn(II) removal within pH range between 4.0 to 6.0 at the temperature of 25°C rather than KNPs. Both KNP and MKNP exhibited two-stage kinetic behavior and reached to their equilibrium adsorption capacity within 30 min. The adsorption of Zn(II) on KNPs and MKNPs followed pseudo second order kinetic model. It was found that the experimental data were best fitted to Sips or Redlich-Peterson isotherm when KNP was used as biosorbent. Unlike KNP, MKNP conformed better to Langmuir model. The maximum adsorption capacity of MKNP at two doses of 3.0 and 5.0 g/L was calculated to be 30 and 18 mg/g, respectively. As the dosage of MKNP raised from 3.0 to 5.0 g/L, the value of KL increased from 0.045...
Direct oxidation of benzene to phenol in liquid phase in the medium of methanol, acetone, acetic ... more Direct oxidation of benzene to phenol in liquid phase in the medium of methanol, acetone, acetic acid and acetonitrile as a solvent over chromium catalyst supported on highly ordered nanoporous silica (Cr-LUS-1) by H O were examined. The best results obtained from methanol solvent with 20% yield and selectivity of 90%. 22 Cr-LUS-1 characterized by XRD, nitrogen adsorption-desorption isotherms and visible spectrophotometer.
Potassium chloride nanoparticles were produced by an innovative technique “induced crystallizatio... more Potassium chloride nanoparticles were produced by an innovative technique “induced crystallization in presence of stabilizer”. An anti-solvent was used to create supersaturation in an aqueous potassium chloride solution. Nanoparticles were produced in presence of polyvinylpyrrolidone (PVP). Induction time of nanoparticles formation was measured and correlated with supersaturation to determine the nucleation mechanism. Results show that primary homogenous nucleation is dominant. Interfacial tension of nanoparticles was calculated and solubility data for potassium chloride in acetone+water solution was determined. The method is versatile in producing various mineral and organic nanoparticles while induction time for nucleation can be determined most easily and precisely because the anti-solvent can be added in a highly controlled routine.
Nucleation is a fundamental process widely studied in different areas of industry and biology. Th... more Nucleation is a fundamental process widely studied in different areas of industry and biology. This review paper comprehensively discussed the principles of classical nucleation theory (primary homogeneous), and heterogeneous nucleation. In the homogeneous part, the nucleation rate in the transient and intransient state is monitored and also heterogeneous nucleation is covered. Finally, conclusions have been deduced from the collected works studied here, and offers for future studies are proposed.
The present study aims to investigate the water diffusivity into polystyrene/ calcium sulfate (PS... more The present study aims to investigate the water diffusivity into polystyrene/ calcium sulfate (PS/CaSO4) nanocomposite samples as a threat to the intended reinforcing properties. For this purpose, CaSO4 nanoparticles were synthesized through a chemical reaction using polyethylene glycol as the stabilizing agent. The polystyrene/calcium sulfate nanocomposites were fabricated through in situ polymerization of styrene monomer and stearic acid coated CaSO4 nanoparticles. SEM analysis was applied to determine the size and shape of the produced nanoparticles. In addition, TEM analysis was applied to study the general morphology and structure of the nanocomposites in order to confirm the PS/CaSO4 nanocomposites formation. FTIR analysis was employed to study the surface functions and bonds formation in both the surface treatment and nanocomposite preparation steps. Water diffusivity into the nanocomposites was evaluated through samples water exposure followed by calculation of the effective...
In this study, the effect of gamma alumina-based molybdenum oxide nanoparticles, on the viscosity... more In this study, the effect of gamma alumina-based molybdenum oxide nanoparticles, on the viscosity reduction of extra-heavy crude oil in a catalytic cracking process in atmospheric pressure and at 250–350 °C investigated for the first time. Molybdenum oxide nanoparticles synthesized using the polyol method and heating by microwave radiation. According to the dynamic light scattering (DLS) analysis, obtained nanoparticles have an average size of 6 nm. These nanoparticles coated on gamma-alumina powder using the novel method of per-vaporation, and through this method, 0.011 g of molybdenum oxide nanoparticles coated over per 1 g of catalyst, during 14 days. The performance of the synthesized catalysts in the cracking process of extra-heavy crude oil investigated. Statistical design of the experiment (DOE) used to study the effect of catalyst concentration and process temperature on product viscosity and to obtain optimal value of these factors. Based on the central composite design (CCD) method, the cubic model developed to correlate the catalyst wt% and temperature for upgraded oil viscosity. By applying the synthesized nanocatalyst in the range of 0.59–4 wt%, the viscosity reduction from 32 to 86% was observed. The highest viscosity reduction happened at 350 °C and 2% weight percent of nanocatalysts, in which the viscosity reduced from 20,000 cp to 2800 cp.
Abstract For the first time, numerous experiments were carried out to evaluate the effect of elec... more Abstract For the first time, numerous experiments were carried out to evaluate the effect of electric field (EF) on the mechanism of naturally occurring THF hydrate formation. The Statistical Package for the Social Sciences (SPSS) software was utilized to analyze the experimental data. First, the effect of static electric field (SEF) strength on nucleation temperature (T-nuc) and growth time (t-growth) studied. Based on the statistical results, increasing the intensity of SEF induces nucleation at a relatively high temperature. Furthermore, the completion of solidification takes a longer time than the same process in the absence of SEF. The notable point is that by switching a SEF to a pulsed electric field (PEF) of equal voltage, the EF effectiveness on the two mentioned kinetic parameters significantly reduces. The other point is that applying EF heightens the enthalpy of fusion of THF hydrate.
Journal of Dispersion Science and Technology, Jul 25, 2014
ABSTRACT Froth flotation was employed for quantitative separation of graphene oxide nanoribbon (G... more ABSTRACT Froth flotation was employed for quantitative separation of graphene oxide nanoribbon (GONR) from its solution. The effects of GONR concentration, pH, and cetyltrimethyl ammonium bromide (CTAB) concentration on GONR separation were studied through a Box–Behnken experimental design method. F value of 176.47, coefficient of determination of 0.9969, adjusted R2 of 0.9912, and coefficient of variation of 4.09%, explored by means of analysis of variance, implied the satisfactory adjustment of the obtained quadratic model. The results indicated that low GONR and high CTAB concentration at low pH were ideal for maximum separation by flotation.
In the present study, silver nanoparticles were synthesized by decomposition of AgNO3 via gelcast... more In the present study, silver nanoparticles were synthesized by decomposition of AgNO3 via gelcasting. Methacrylamide was used as a low toxic monomer for gel formation. Effect of monomer content (MAM), cross-linker to monomer ratio (MBAM/MAM), silver salt to monomer ratio (AgNO3/MAM), duration of calcination, and temperature of calcination were investigated to optimize the size of nanoparticles. Taguchi method was applied to study the effect of gelcasting parameters on the size of silver nanoparticles. Mentioned parameters were surveyed at four levels and based on the Taguchi method 16 experiments were carried out. Silver nanoparticles were characterized, and average particle sizes were measured by SEM analysis. By using the signal to noise ratio (S/N) analysis of the results, it is revealed that monomer content is the most effective parameter on size of particles. Also, optimal values of monomer content, cross-linker to monomer ratio, silver salt to monomer ratio, duration of calcin...
International Journal of NanoScience and Nanotechnology, 2018
Nickel-molybdenum oxidebimetallic nanoparticles were synthesized in ethylene glycol using the mic... more Nickel-molybdenum oxidebimetallic nanoparticles were synthesized in ethylene glycol using the microwave irradiation technique. According to the results, successive reduction of nickel and molybdenum ions, followed by thermal treatment of obtained nanoparticles led to formation of core-shell structured nickel-molybdenum oxide nanoparticles. According to the results, the thickness of the shell and core were 5 and 40 nm, respectively. The structure and composition of nanoparticles were characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), UV-vis spectroscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS).
Advances in environmental science and technology, 2018
A straightforward procedure to synthesize keratin nanoparticles (KNP) from chicken feathers was i... more A straightforward procedure to synthesize keratin nanoparticles (KNP) from chicken feathers was introduced. The characterization of the synthesized nanoparticles was done using Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD) patterns and transmission electron microscopy (TEM). The FTIR analysis revealed no significant chemical change after the nanoparticle synthesis. TEM imaging indicated the synthesis of KNPs with a spherical morphology and mean size of 42 nm. The DLS results indicated that the synthesized KNPs were stable in aqueous media by having a zetapotential of lower than -30 mV. The produced KNPs were then evaluated for the biosorption of Cu (II) from aqueous solutions. The analyzed adsorption isotherm data revealed the change from a Redlich-Peterson isotherm to a Langmuir one by increasing the biosorbent dosage, which could be attributed to the more prepared adsorption sites. The experiments of the effect of the bioso...
A major portion of BaSO4 is used as drilling fluid additives in the presence of some biopolymers ... more A major portion of BaSO4 is used as drilling fluid additives in the presence of some biopolymers such as starch and PAC (Polyanionic Cellulose) as filtration control and viscosifier. BaSO4 nanoparticle was synthesized in the presence of these applicable polymers with precipitation method by using BaS produced from carbothermal method and Na2SO4. Synthesized nanoparticles size and morphology were analyzed using DLS (Dynamic Light Scattering) and FESEM (Field Emission Scanning Electron Microscope). It can be concluded that, nanoparticles size have inverse proportion with polymer concentration. Also nanoparticles have smaller size in the presence of PAC with longer functional group than starch and prevent chemical reaction due to steric hindrance. If pH increases from 7 to 11, nanoparticles in starch had minimum size in pH=9 and various pH didn’t have noticeable effect on size with PAC. In kinetic study, conductometer is used to detect induction time in different Na2SO4 concentrations ...
Research subject: The use of nanoparticles, especially nanoantibiotics, increases their efficacy.... more Research subject: The use of nanoparticles, especially nanoantibiotics, increases their efficacy. More uniform release of antibiotics is one of the benefits of their nano size. They can be made using ointment or banderol to be absorbed through the skin to the infection, thereby reducing its side effects. Amoxicillin is one of the most widely used antibiotics in the world which can prevent the use of other stronger antibiotics, provided that its efficacy is promoted in the form of nanoparticles. Determining the mechanism of nanoparticle formation of this drug is an important factor for its commercial production. Research approach: The purpose of this study was to determine the nucleation mechanism and induction time of crystallization of amoxicillin nanoparticles in the presence of surface active agents ‘CTAB’ and ‘SDS’. Therefore, the effect of amoxicillin concentration and stabilizing agent concentration on the crystallization process was investigated. In this project, a combinatio...
The comparative sorption studies were carried out to investigate the performance of keratin nanop... more The comparative sorption studies were carried out to investigate the performance of keratin nanoparticles (KNPs) and magnetic KNPs (MKNPs) for Zn(II) uptake. MKNPs showed remarkably higher Zn(II) removal due to the lower keratin weight percent in its structure (8.4%). MKNPs revealed relatively uniform Zn(II) removal within pH range between 4.0 to 6.0 at the temperature of 25°C rather than KNPs. Both KNP and MKNP exhibited two-stage kinetic behavior and reached to their equilibrium adsorption capacity within 30 min. The adsorption of Zn(II) on KNPs and MKNPs followed pseudo second order kinetic model. It was found that the experimental data were best fitted to Sips or Redlich-Peterson isotherm when KNP was used as biosorbent. Unlike KNP, MKNP conformed better to Langmuir model. The maximum adsorption capacity of MKNP at two doses of 3.0 and 5.0 g/L was calculated to be 30 and 18 mg/g, respectively. As the dosage of MKNP raised from 3.0 to 5.0 g/L, the value of KL increased from 0.045...
Direct oxidation of benzene to phenol in liquid phase in the medium of methanol, acetone, acetic ... more Direct oxidation of benzene to phenol in liquid phase in the medium of methanol, acetone, acetic acid and acetonitrile as a solvent over chromium catalyst supported on highly ordered nanoporous silica (Cr-LUS-1) by H O were examined. The best results obtained from methanol solvent with 20% yield and selectivity of 90%. 22 Cr-LUS-1 characterized by XRD, nitrogen adsorption-desorption isotherms and visible spectrophotometer.
Potassium chloride nanoparticles were produced by an innovative technique “induced crystallizatio... more Potassium chloride nanoparticles were produced by an innovative technique “induced crystallization in presence of stabilizer”. An anti-solvent was used to create supersaturation in an aqueous potassium chloride solution. Nanoparticles were produced in presence of polyvinylpyrrolidone (PVP). Induction time of nanoparticles formation was measured and correlated with supersaturation to determine the nucleation mechanism. Results show that primary homogenous nucleation is dominant. Interfacial tension of nanoparticles was calculated and solubility data for potassium chloride in acetone+water solution was determined. The method is versatile in producing various mineral and organic nanoparticles while induction time for nucleation can be determined most easily and precisely because the anti-solvent can be added in a highly controlled routine.
Nucleation is a fundamental process widely studied in different areas of industry and biology. Th... more Nucleation is a fundamental process widely studied in different areas of industry and biology. This review paper comprehensively discussed the principles of classical nucleation theory (primary homogeneous), and heterogeneous nucleation. In the homogeneous part, the nucleation rate in the transient and intransient state is monitored and also heterogeneous nucleation is covered. Finally, conclusions have been deduced from the collected works studied here, and offers for future studies are proposed.
The present study aims to investigate the water diffusivity into polystyrene/ calcium sulfate (PS... more The present study aims to investigate the water diffusivity into polystyrene/ calcium sulfate (PS/CaSO4) nanocomposite samples as a threat to the intended reinforcing properties. For this purpose, CaSO4 nanoparticles were synthesized through a chemical reaction using polyethylene glycol as the stabilizing agent. The polystyrene/calcium sulfate nanocomposites were fabricated through in situ polymerization of styrene monomer and stearic acid coated CaSO4 nanoparticles. SEM analysis was applied to determine the size and shape of the produced nanoparticles. In addition, TEM analysis was applied to study the general morphology and structure of the nanocomposites in order to confirm the PS/CaSO4 nanocomposites formation. FTIR analysis was employed to study the surface functions and bonds formation in both the surface treatment and nanocomposite preparation steps. Water diffusivity into the nanocomposites was evaluated through samples water exposure followed by calculation of the effective...
In this study, the effect of gamma alumina-based molybdenum oxide nanoparticles, on the viscosity... more In this study, the effect of gamma alumina-based molybdenum oxide nanoparticles, on the viscosity reduction of extra-heavy crude oil in a catalytic cracking process in atmospheric pressure and at 250–350 °C investigated for the first time. Molybdenum oxide nanoparticles synthesized using the polyol method and heating by microwave radiation. According to the dynamic light scattering (DLS) analysis, obtained nanoparticles have an average size of 6 nm. These nanoparticles coated on gamma-alumina powder using the novel method of per-vaporation, and through this method, 0.011 g of molybdenum oxide nanoparticles coated over per 1 g of catalyst, during 14 days. The performance of the synthesized catalysts in the cracking process of extra-heavy crude oil investigated. Statistical design of the experiment (DOE) used to study the effect of catalyst concentration and process temperature on product viscosity and to obtain optimal value of these factors. Based on the central composite design (CCD) method, the cubic model developed to correlate the catalyst wt% and temperature for upgraded oil viscosity. By applying the synthesized nanocatalyst in the range of 0.59–4 wt%, the viscosity reduction from 32 to 86% was observed. The highest viscosity reduction happened at 350 °C and 2% weight percent of nanocatalysts, in which the viscosity reduced from 20,000 cp to 2800 cp.
Abstract For the first time, numerous experiments were carried out to evaluate the effect of elec... more Abstract For the first time, numerous experiments were carried out to evaluate the effect of electric field (EF) on the mechanism of naturally occurring THF hydrate formation. The Statistical Package for the Social Sciences (SPSS) software was utilized to analyze the experimental data. First, the effect of static electric field (SEF) strength on nucleation temperature (T-nuc) and growth time (t-growth) studied. Based on the statistical results, increasing the intensity of SEF induces nucleation at a relatively high temperature. Furthermore, the completion of solidification takes a longer time than the same process in the absence of SEF. The notable point is that by switching a SEF to a pulsed electric field (PEF) of equal voltage, the EF effectiveness on the two mentioned kinetic parameters significantly reduces. The other point is that applying EF heightens the enthalpy of fusion of THF hydrate.
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