XML
-
-
List of Articles
-
Open Access Article
1 - High efficient solar light photocatalytic degradation of malachite green by solid state synthesized Bi2Sn2O7 and Bi2MxSn2O7 (M = Y3+, Eu3+, Gd3+ and Yb3+) nanomaterials
hassan GHEISARI Ebrahim Karamian Ali SoheilyNanostructured Bi2Sn2O7 and Bi2MxSn2O7 (M = Y3+, Eu3+, Gd3+ and Yb3+)nanomaterials were synthesized by conventional one-step solid state crystalgrowth reactions among Bi(NO3)3, SnCl2 and M2O3 raw materials at 800 ̊C for 10and 15 h. The doped nanomaterials were synthesiz MoreNanostructured Bi2Sn2O7 and Bi2MxSn2O7 (M = Y3+, Eu3+, Gd3+ and Yb3+)nanomaterials were synthesized by conventional one-step solid state crystalgrowth reactions among Bi(NO3)3, SnCl2 and M2O3 raw materials at 800 ̊C for 10and 15 h. The doped nanomaterials were synthesized to study the capacity of thecrystal system to locate each of the dopant ions into the crystal system cavities.The synthesized nanomaterials were characterized by powder X-ray diffraction(PXRD) technique. Rietveld analysis showed that the obtained materials werecrystallized well in orthorhombic crystal structure with the space group Aba2.The PXRD data revealed that dopant ion type had a considerable influence on thecrystal phase purity of the obtained targets. The morphologies of the synthesizedmaterials were studied by field emission scanning electron microscopy (FESEM)technique. Ultraviolet-visible spectra analysis showed that the synthesizednanomaterials had strong light absorption in the ultraviolet light region.Photocatalytic performance of the synthesized nanomaterials was investigatedfor the degradation of pollutant Malachite Green under solar light condition. Theoptimum conditions were modeled and obtained by design expert software forBi2Sn2O7 that was synthesized at 800 ̊C for 10 h which were 0.06 mL H2O2, 12mg catalyst and 40 min for the removal of 50 mL of 40 ppm MG solution. Thedegradation yield in these conditions was 100 %. The photocatalytic degradationfitted to the Langmuir–Hinshelwood kinetic model. As a result of the model, thekinetic of degradation followed a pseudo-zero-order kinetic model. Manuscript profile -
Open Access Article
2 - Efficient photocatalytic desulfurization of thiophene under visible light irradiation over flower-like AgBiS2 photocatalyst
Mehdi Mousavi-Kamazani Reza Rahmatolahzadeh Hassan NajafianHere, we report the production of hierarchical flower-like AgBiS2 nanostructuresby an amino acid-modified polyol route. This work indicates that by changing thepolyol process conditions including kind of capping agent, reaction time and refluxtemperature, the sheet-like MoreHere, we report the production of hierarchical flower-like AgBiS2 nanostructuresby an amino acid-modified polyol route. This work indicates that by changing thepolyol process conditions including kind of capping agent, reaction time and refluxtemperature, the sheet-like, cone-like, sphere-like and flower-like morphologies ofAgBiS2 micro/nanostructures can be prepared. The phase, elemental composition,morphology and optical characteristics of as-prepared AgBiS2 nanostructures wereanalyzed by UV–Vis, FESEM, XRD, and EDS techniques. After characterization ofthe products, the AgBiS2 nanostructures were employed as novel photocatalystsfor oxidative desulfurization of thiophene/n-octane solution as model fuel undervisible light illumination. Results demonstrate that hierarchical flower-like AgBiS2photocatalyst with desirable band gap energy (2.44 eV) has high photocatalyticdesulfurization performance of about 89% after 2 h of visible light irradiation.As well as, the effects of morphology, photocatalyst dosage and reusability ofthe AgBiS2 nanostructures on the photocatalytic performance were evaluated.The excellent photocatalytic activity of AgBiS2 photocatalyst can be attributedto the strong visible light absorption, high separation rate of electron–hole pairs,special hierarchical structures and suitable band gap energy. Moreover, a reliablephoto-oxidation desulfurization mechanism was discussed according to theactive species trapping experiments, which revealed the photo-generated h+ and•O2− radicals were the main active species in the photocatalytic desulfurizationprocess. Manuscript profile -
Open Access Article
3 - A soft tissue fabricated using a freeze-drying technique with carboxymethyl chitosan and nanoparticles for promoting effects on wound healing
Atiyeh Raisi Azadeh Asefnejad Maryam Shahali Zahra Doozandeh Bahareh Kamyab Moghadas Saeed Saber-Samandari Amirsalar KhandanObjective(s): Many people suffer from skin injuries due to various problems such asburns and accidents. Therefore, it is essential to shorten treatment time and providingstrategies that can control the progression of the wound that would be effective inwound healing pro MoreObjective(s): Many people suffer from skin injuries due to various problems such asburns and accidents. Therefore, it is essential to shorten treatment time and providingstrategies that can control the progression of the wound that would be effective inwound healing process and also reduce its economic costs.Methods: The present study aimed to prepare a nanocomposite dressing (NCD)composed of carboxymethyl chitosan (CMC), and Fe2O3 nanoparticles by a methodcalled freeze-drying (FD) technique. The effect of different weight percentages ofFe2O3 (0, 2.5, 5, and 7.5 wt%) reinforcement on mechanical and biological propertiessuch as tensile strength, biodegradability, and cell behavior was evaluated. Also, theX-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis were used tocharacterize the soft porous membrane. The biological response in the physiologicalsaline was performed to determine the rate of degradation of NCD in phosphatebuffer saline (PBS) for a specific time.Results: The obtained results demonstrated that the wound dress was porousarchitecture with micron-size interconnections. In fact, according to the results, asthe magnetite nanoparticles amount increases, the porosity increases too. On theother hand, the tensile strength was 0.32 and 0.85 MPa for the pure sample and thesample containing the highest percentage of magnetic nanoparticles, respectively.Besides, the cytotoxicity of this nanocomposite was determined by MTT assays for 7days and showed no cytotoxicity toward the growth of fibroblasts cells and had properin vitro biocompatibility. The obtained results revealed that NCD had remarkablebiodegradability, biocompatibility, and mechanical properties. Therefore, NCDcomposed of CMC and Fe2O3 nanoparticles was introduced as a promising candidatefor wound healing applications.Conclusions: According to the obtained results, the optimum NCD specimen with 5wt% Fe2O3 has the best mechanical and biological properties. Manuscript profile -
Open Access Article
4 - Synthesis and Characterization of forsterite nanopowder ceramic via mechanical activation
Hassan GHEISARIThis project investigates the synthesis of single-phase nano crystalline forsteritepowder by mechanical activation with subsequent annealing. To produceforsterite powder, a mixture of talc and magnesium oxide powders was first milledby a planetary ball mill, and then an MoreThis project investigates the synthesis of single-phase nano crystalline forsteritepowder by mechanical activation with subsequent annealing. To produceforsterite powder, a mixture of talc and magnesium oxide powders was first milledby a planetary ball mill, and then annealed at 1000 and 1200 8C for 1 h. Thesynthesized powder was characterized by X-ray diffraction (XRD), simultaneousthermal analysis (STA), scanning electron microscopy (SEM), and atomicabsorption spectrometry (AAS). The initial temperature of forsterite crystallizationwas reduced to about 825 8C after 20 h of mechanical activation. The forsteritepowder synthesized by 5 h of mechanical activation with subsequent annealingat 1000 8C for 1 h had crystallites 40 n min size. The particle size of this samplewas less than 500 nm. Manuscript profile -
Open Access Article
5 - Using ZnO based on Bentonite as a nano photocatalyst for degradation of Acid Red 114 in synthetic wastewater
Reza Hekmatshoar Ahmad Reza Yari Aref ShokriIn this project, the removal of Acid Red 114(AR 114) that is a mono Azoo dye withglobal usage in an aqueous environment was explored by nano photocatalyticprocess. The ZnO was supported on Bentonite and used at suspension state ina batch photoreactor. The catalyst was s MoreIn this project, the removal of Acid Red 114(AR 114) that is a mono Azoo dye withglobal usage in an aqueous environment was explored by nano photocatalyticprocess. The ZnO was supported on Bentonite and used at suspension state ina batch photoreactor. The catalyst was synthesized by co precipitation methodsand characterized by Scanning Electronic Microscopy (SEM), X-Ray Diffraction(XRD), and Fourier Transform Infrared (FT-IR) spectra. The effect of operationalvariables including pH, initial concentration of Acid red 114, amounts of catalystsand temperature were investigated on the removal efficiency of AR114. Theoptimum conditions were achieved at 1g/l of catalyst, 30 mg/l of AR 114, pH of9 and temperature at 35oC. The removal of AR 114 in UV, UV/ZnO, and UV/ZnO/Bentonite process were 26.5, 55 and 92.5% after 2 h of treatment, respectively.The photo catalytic degradation mechanism was described and the efficiency ofthe process increased considerably by modification of photocatalyst. Manuscript profile -
Open Access Article
6 - The Morphology of Zinc Sulfide Nanocrystals Synthesized by Different Methods
Mina Adibi Sohrab Taghipoor Rava Parhizkar Seyed Mojtaba MostafaviIn recent years, nanostructured materials have attracted a great deal of attentiondue to their special properties as compared to bulk materials. Semiconductornanoparticles can be synthesized in several methods, including chemical capping,reverse micelles, and hydrotherm MoreIn recent years, nanostructured materials have attracted a great deal of attentiondue to their special properties as compared to bulk materials. Semiconductornanoparticles can be synthesized in several methods, including chemical capping,reverse micelles, and hydrothermal. In this research, different methods of ZnSnanoparticle fabrication and the role of the main parameters on the particle sizeand morphology of the samples were investigated by validated methods such asSEM, TEM, XRD and EDAX. In all mentioned methods, decreasing the concentrationof reactants reduces the particle diameter. Also, increasing the rate of addition ofthe reactants reduces the size of the produced nanoparticles. The results of SEMand TEM imaging show that the hydrothermal method using thioacetamide as asource of sulfide ion, in addition to the uniformly formed nanoparticles, has highreproducibility which is a good criterion for increasing the scaling rate. Manuscript profile -
Open Access Article
7 - Performance Optimization and Sensitivity Analysis of Junctionless FinFET with Asymmetric Doping Profile
Zahra Ahangari Ehsan Asadi Seied Ali HosseiniIn this paper, a novel junctionless fin field effect transistor (FinFET) withasymmetric doping profile along with the device from source to drain (ADJFinFET)is introduced and the electrical characteristics of the device are comprehensivelyassessed. Unlike the convention MoreIn this paper, a novel junctionless fin field effect transistor (FinFET) withasymmetric doping profile along with the device from source to drain (ADJFinFET)is introduced and the electrical characteristics of the device are comprehensivelyassessed. Unlike the conventional junctionless FinFET, ADJFinFET has lowerchannel doping density with respect to the adjacent source and drain regions,which provides superior electrical performance in nanoscale regime. The impactof device geometry and physical design parameters on the device performanceare thoroughly investigated via calculating standard deviation over mean valueof main electrical measures. The sensitivity analysis reveals that metal gateworkfunction, doping density and fin width are critical design parameters thatmay fundamentally modify the device performance. Furthermore, 2D variationmatrix of gate workfunction and channel doping density is calculated foroptimizing the device performance in terms of off-state and on-state current. Theresults demonstrate that the proposed device establishes a promising candidateto realize the requirements of low-power high-performance integrated circuits. Manuscript profile -
Open Access Article
8 - An investigation of carbon nanotubes on shear stress, thermal conductivity and the viscosity of Nanofluids
Aref ShokriThe Nanofluid includes suspensions containing nanoparticles, which are dispersedin the base fluid homogeneously. In this study, nanoparticles called multi-walledcarbon nanotubes (MWCNT) were dispersed in a pure water-based fluid. The shape,size, and arrangement of carbo MoreThe Nanofluid includes suspensions containing nanoparticles, which are dispersedin the base fluid homogeneously. In this study, nanoparticles called multi-walledcarbon nanotubes (MWCNT) were dispersed in a pure water-based fluid. The shape,size, and arrangement of carbon nanotubes were displayed by the transmittanceelectron microscope (TEM) and scanning electron microscope (SEM) techniques.The thermal conductivity and viscosity of the resulting nanofluid were measuredexperimentally. The carbon nanotubes within the nanofluid were stabilized usingSodium dodecyl benzene sulphate. The effect of carbon nanotubes on shearstress, thermal conductivity and viscosity of fluids has investigated. The resultsshowed that at 308K the thermal conductivity was increased from 0.6 to 0.94w/m.ºC with an increase in the volumetric concentration of MWCNTs from 0 to0.015%. And the thermal conductivity was increased from 0.74 to 0.94 w/m.ºCwith increase in temperature from 298 to 308K. The shear stress was increasedfrom 10.8 to 11.9 N/m2 at 298K by increase in the volumetric concentrationof MWCNTs from 0 to 0.015% and it was reduced from 11.9 to 9.2 N/m2 withenhance in temperature from 298 to 308K, respectively. Manuscript profile
-
The rights to this website are owned by the Raimag Press Management System.
Copyright © 2021-2024