Bulgarian Chemical Communications, Volume 50, Special Issue-L, 2018 |
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Structure and performance of PDMS as cross-linking agent upon property of blending PDMS, PEG, PES and PAN membranes
Original Research Article
Pages 5 – 11
M. Farsi, A.Heidarinasab, B.Honarvar, M. Arjmand
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(943 KB)
Abstract
In this research for fabricated the composite membranes usage a blend of polymers that are comprised of PDMS (polydimethylsiloxane), PEG (polyethylene glycol), PES (polyether sulfonic) and PAN (poly acryl nitrile) as polymers, asymmetric polyester ultra-filtration membranes, PES, PVP (polyvinyl pyrrolidone) as pore former and N,N-Dimethyl acetamide (DMAc) as solvent used for fabricated of support layer with crosslinking PDMS as crosslinking agent, ammonia as inducer ,dibutyltin dilaurate as catalyst and span 80 as surfactant.In the research, four kinds of the membrane including PDMS, blend of PDMS with PEG, blend of PDMS with PES and blend of PDMS with PAN are used. The structural morphology of support and active layers of the composite membranes was characterized with SEM. in this research, crosslinking temperature and crosslinking time are fixed and 70ċ and 1 hour respectively so this study focuses on the variation of crosslinking agent (PDMS)(1.5,3 ,4.4,5.8 and 7.15wt%) upon crosslinking density (Ve), swelling degree (MSD), %swelling by volume, density of membrane specimen (ρP), volume fraction of rubber phase (V2) and number average molecular weight between crosslink's (MC), is studied. It was observed that with increasing the weight of the crosslinking agent,Ve ,ρP and V2 increased and MSD , %swelling by volume decreased, but changes of MCis erratic.
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The effect of using nanostructures of synthesized lead oxide by mechanical milling on lead-acid battery performance using Taguchi method
Original Research Article
Pages 12 – 17
M. Omidvar, E. Koohestanian, O. Ramezani
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(1479 KB)
Abstract
In this research, the effect of anode surface electrode coating on acidic lead batteries was investigated using nano-structured lead oxide synthesized by mechanical milling process. Investigations indicates that according to the different conditions of synthesis by mechanical milling, morphology, structural porosity, particle size, and electromagnetic properties are changed. Therefore, in this research, the effect of different parameters of mechanical milling process, such as milling time and ball-to-powder ratio, were optimized to obtain longer drain times of battery. For this purpose, the battery plates were coated using different levels of lead oxide nanostructures and the time spent on discharge of the batteries was measured and the results were analyzed by statistical software. The results show that the coating of battery plates with lead oxide nanostructures will increase the battery discharge time. So that the battery discharge time built using an optimal sample is better than normal battery life. Due to the high volume of nanostructures produced in the mechanical milling method, as well as the simplicity and cost-effectiveness of this method, the results of the research justify its use for industrial and large-scale applications. |
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Nano-sawdust-SbCl5 as a new, green and effective nano catalyst for one-pot synthesis of pyrano [4,3-b] pyrans
Original Research Article
Pages 18 – 22
S. Dehghanpoor, B. Sadeghi, M.Mosslemin
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(586 KB)
Abstract
Nano-sawdust-SbCl5 as a new and mild solid acid catalyst is applied to the synthesis of biologically important pyrano [4,3-b] pyrans. The reaction involves the use of 4-hydroxy-6-methyl-2H-pyran-2-one, malononitrile and aldehydes. The procedure is very simple and the products are isolated with an easy workup in good-to-excellent yields. The morphology of nanocatalyst (nano-sawdust-SbCl5) was observed using a scanning electron microscopy (SEM). Also, the vibrational spectrum analysis (FT-IR) of the catalyst has been performed. |
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Nano-cellulose-SBCL5 as a new heterogeneous nano catalyst for the one-pot synthesis of spirooxindoles under mild conditions
Original Research Article
Pages 23 – 28
M. Rouhi, B. Sadeghi, M.Moslemin
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(722 KB)
Abstract
Natural thiols (TSH) cysteine, glutathione, and homocysteine, as well as catecholamines (CA) dopamine, noradrenaline and adrenaline are known as multifunctional biologically active compounds with antioxidant potential, i.e. bio-antioxidants, which play an important role in the regulation of the redox status and free radical formation – utilization in living organisms. The kinetic characteristics of interaction of TSH and CA with peroxyl radicals, RO2•, formed from the azo-initiator AAPH in aqueous solutions at 37°C by the method of competing reactions were determined. The kinetics of radical formation in the reactions of TSH with H2O2 was studied by the inhibitors method. The polymethine dye (A, pyridine salt of 3,3'-di-ϒ-sulphopropyl-9-methylthia-carbocyanine betaine) was used as a radical scavenger. CA demonstrated the highest antiradical activity (ki> 106(M·s)-1, whereas TSH possess moderate activity (ki 105(M·s)-1). |
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Nano-kaolin-TiCl4 as a new, green and effective nano catalyst for one-pot synthesis of tetrahydrobenzo[B]pyrans
Original Research Article
Pages 29 – 32
E. Abyar, B. Sadeghi, M.Mosslemin
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(404 KB)
Abstract
Nano-kaolin-TiCl4 as a new and mild solid acid catalyst is applied to the synthesis of biologically important tetrahydrobenzo[b]pyrans. The reaction involves the use of an aromatic aldehyde, malononitrile and dimedone. The procedure is very simple and the products are isolated with an easy workup in good-to-excellent yields. The morphology of nanocatalyst (nano-kaolin-TiCl4) was observed using a scanning electron microscopy (SEM). Also, the vibrational spectrum analysis (FT-IR) of the catalyst has been performed. |
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Introduction of KIANA radio ecological Iranian domestic code for concentration and dose calculation of radio isotopes release at normal and accidental conditions in nuclear installations and chemical facilities
Original Research Article
Pages 33 – 58
A.Haghighi Shad, D.Masti, M.Athari Allaf, K.Sepanloo, S.A.H.Feghhi
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(3498 KB)
Abstract
Introduction of A domestic user friendly dynamic radiological dose and model has been developed to estimate radiation doses and stochastic risks due to atmospheric and liquid discharges of radionuclides in the case of a nuclear reactor accident and normal operation in nuclear installations and can be useful for modelling and concentration calculations of dispersion of radiochemical to atmosphere in chemical facilities. In addition to individual doses from different pathways for different age groups, collective doses and stochastic risks and sewerage discharge to environment as release pathway can be calculated by the developed domestic user friendly KIANA Advance Computational Computer Code and model. The current Code can be coupled to any long-range atmospheric dispersion/short term model which can calculate radionuclide concentrations in air and on the ground and in the water surfaces predetermined time intervals or measurement data. The nuclear and radioactive installations release radionuclides to the environment, affecting the atmosphere, the terrestrial surface and the surface waters, as rivers, coastal waters, estuaries, lakes and small reservoirs. The flora, fauna and human beings are directly affected by those releases, since air and water are the main flora nutrients, flora is part of the fauna diet, and flora and fauna constitute the human being feed. User Friendly KIANA Advance Computational Computer Code application is a code that designed to automate the calculation of radionuclide concentrations in different environments and their impact in the nutritional chain, as well as in the human being, allowing to the researcher to center in the obtained results analysis. |
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Investigation of interaction between graphene and its compounds as carriers on anti-cancer drug of 5-fluorouracil
Original Research Article
Pages 59 – 62
A.S. Mohamadhoseini, S. Jamehbozorgi, J. Beheshtian
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(911 KB)
Abstract
5-fluorouracil molecule (5-FU) is a fluorinated pyrimidine analogue chemotherapeutic agent using as solid cancer treatment like esophagus, stomach, intestines, and carcinoma. The adsorption process as the first factor in drug conductivity systems is very important, and also in this study, importance of adsorption, for measuring the efficiency of graphene as drug carriers was studied. In this study, the electronic and adsorption properties of the graphene interacted with 5-fluorouracil molecule (5-FU) were theoretically investigated in the gas phase using the B3LYP density functional theory (DFT) calculations and 6-311G* basis set. Graphene due to its unique properties is very important compound. It was found that the adsorption behavior of 5FU molecule on the Graphene are electrostatic in nature. |
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Nano-cellulose-OSO3H as a green and effective nano catalyst for one-pot synthesis of pyrano [2,3-D] pyrimidines
Original Research Article
Pages 63 – 68
B.Sadeghi, A. Moradgholi, E. Akbarzadeh
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(430 KB)
Abstract
A straightforward and efficient synthetic methodology has been developed for the preparation of biologically important pyrano [2,3-d] pyrimidines using nano-Cellulose-OSO3H as a new catalyst. The reaction involves the use of barbituric acid, ethylcyanoacetate and aldehydes. A wide range of aldehydes is compatible in this reaction, producing excellent yields in short time. The morphology of nanocatalyst (nano-Cellulose-OSO3H) was observed using a transmission electron microscopy (TEM). The Cellulose-OSO3H surface was studied by energy dispersive X-ray spectroscopy (EDX) method to find out the chemical composition. Also, the vibrational spectrum analysis (FT-IR) of the catalyst has been performed. |
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The effect of microwave irradiation on operational parameters of copper flotation concentrate bioleaching by irradiated mesophilic bacteria
Original Research Article
Pages 69 –75
M.M. Royaei, A. Pourbabaee, M. Noaparast
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(682 KB)
Abstract
Previous bioleaching experiments carried out on Sarcheshmeh copper concentrate samples revealed that the optimum bioleaching operational condition are as temperature 32°C, pH 1.8 and agitation rate 125 rpm. A control bioleaching test was carried out using this optimum operational condition and the obtained copper recovery was 34.2% after 30 days which was in conjunction with previous researches. This study was carried out with the aim of investigating the effect of microwave irradiation on the operational parameters affecting copper sulfide concentrate bioleaching. With this regard, three commonly used mesophilic bacteria in bioleaching of sulfidic copper concentrate (Acidithiobacillus ferrooxidan, Leptospirillum ferrooxidan and Acidithiobacillus thiooxidan) were treated by microwave irradiation. Microwave irradiation were carried out for 5, 10, 15 and 20 s and the optimum irradiation times were chosen based on oxidation rate test results. The oxidation rate test results showed that optimized time of microwave irradiation for Acidithiobacillus ferrooxidan, Leptospirillum ferrooxidan and Acidithiobacillus thiooxidan were 10, 15 and 10 s respectively. A mixed culture of optimum irradiated bacteria were used in bioleaching experiments. The optimization of bioleaching operational parameters was carried out on initial pH (1.2, 1.5, 1.8 and 2), temperature (32, 38, 44 and 50 °C) and agitation rate (125, 150, 175 and 200 rpm). Using microwave treated bacteria and based on copper extraction results, it was concluded that optimum bioleaching condition is changed to pH 1.5, temperature 44°C and agitation rate 125 rpm and maximum copper recovery obtained under this optimum operational condition for microwave treated mixed culture reached to 44.36% after 30 days. The bioleaching rate was also enhanced using microwave treated mixed cultures, so that the copper recovery was reached to 34.36% after 12 days. |
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Examining the synthesis of organic material used as an oxidation inhibitor for all types of lubricating oils
Original Research Article
Pages 76 – 82
K. Habibi, M. Mamaghani, M. Nikpassand
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(481 KB)
Abstract
The following article introduces all types of industrial lubricating oils, their essential properties, primary compounds, and some additives. The subject that has been discussed in this review is an overview of additives that have an antioxidant role in a variety of industrial lubricants. These additives were first synthesized and then added to the oil by combining different percentages. After synthesis, compounds were identified by using data analysis methods, such as FTIR, NMR... and then mixed with different weight percentages with industrial Lubricating Oils. Some of its physical and chemical properties are studied after mixing, according to the ASTM standard. |
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Nano CeO2/ZnO: A powerful catalyst for the very fast synthesis of quinoxaline
Original Research Article
Pages 83 – 87
L.Nazari, B. Baghernejad
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(539 KB)
Abstract
Quinoxaline derivatives were efficiently synthesized from the condensation of the o-phenylenediamines and 1, 2-
dicarbonyl compounds in the presence catalytic amounts of Nano CeO2/ZnO in good yields.
Nano CeO2/ZnO was found to be an effective catalyst for the synthesis of quinoxaline derivatives from the
condensation of the 1, 2-diamines and 1, 2-dicarbonyl compounds in good yields. The catalyst is recyclable and
reusable. |
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Arsenic (V) removal from aquatic media by electrospun alumina nanofiber
Original Research Article
Pages 88 – 96
H. Hosseini Shekarabi, P. Abroomand Azar, A. Javid, A. Hasani
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(1219KB)
Abstract
Today, it is believed that the world population is encountered with water crisis and some solutions should be presented for this challenge. New technologies are one of the requirements to eliminate these problems. The present study aims to use Nano technology to make a fiber filter called alumina nanofiber by which arsenic-a heavy and toxic metal- is removed via adsorption. The technology applied in this study is electrospinning and it is the most effective method to produce Nano with fiber structure and it is cost effective as it is recovered to be used in nanofiber filter production. This study differs from other studies given that arsenic (V) removal is aimed and polyacrylonitrile (PAN) is used instead of polyvinylpyrolidone (PVP) and it is due to the high thermal resistance of polyacrylonitrile (PAN) and maintenance of leaf structure of nanofibers during sintering process (injection) and deterioration of aluminum precursor. The results show that arsenic (V) removal is examined based on the effect of pH, contact time, initial metal concentration, solution volume and adsorbent dosage parameters. The optimal conditions are pH=2, contact time=60 min, metal initial concentration of 5 mg L-1, solution volume of 50 mL and adsorbent dose of 0.05 g and this removes about 90% of arsenic (V). |
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Synthesis and characterization of metal organic framework based on copper particles for storage of zinc oxide nanoparticles
Original Research Article
Pages 97 – 101
P.Mehrani, N.Ghasemi, M.Ramezani
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(1023 KB)
Abstract
Handled studies show that organic-metal frameworks are as new group from Nano material for storing and separating materials and chemical compounds. This group is attracted attention from porous compounds in recent ten years that because of big size of their holes, their high area, selective attraction of small molecules and optical or magnetic responses in presence of guest molecules. MOFs by collection of ions or metal clusters are made as Coordination Complexes and organic ligands as organic connectors of metal ions. This group has special physical and chemical materials and they are arranged from structure view. In this study of Nano particles of zinc oxide and MOFs based on copper were prepared and by methods FT-IR (Fourier transformation-infrared spectrometer), SEM (Scanning electron microscope), XRD (X-Ray Diffraction) were recognized and then recognition way of MOFs were investigated. At last Nano particles ZnO in porous space of MOFs was synthesized and image of SEM as final compound was proved that metal organic framework madding from suitable copper for Nano particle of ZnO |
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Theoretical model for simulation of the particles drying using gateway dryer: heat and mass transfer study
Original Research Article
Pages 102 – 112
A.Ghadami Jadval Ghadam, M. Shanbehpour
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(1427 KB)
Abstract
In the current research, the simulation of particle drying using gateway dryer was investigated through the MATLAB software, also equations were numerically solved and the particle dehumidifying simulation process was conducted. To this aim, a theoretical model was provided which includes the unstable characteristic of both heat and mass transfer during dehumidifying the wet particle in two stages. This model provided the possibility of predicting pressure and partial dispersions of air-steam combination within the narrow pores in the shell of the wet particle. Simulation of dehumidifying process of silica particle under different conditions showed the permanent increased pressure within the narrow pores of the particle. It is pertinent to put on record that the structure of pressure and increased temperature within the core of wet particle were shown simultaneously; and also the diagrams of time changes of mass, temperature, pressure, vapor and moisture fraction were obtained. |
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Prediction of density for the mixture of octanol and polyethylene glycol using fuzzy and adaptive neuro-fuzzy systems
Original Research Article
Pages 113 – 118
H. Hashemi, A. Ghadami Jadval Ghadam
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(830 KB)
Abstract
Precise determination of the thermodynamic properties like polymer solutions density is useful for the required polymer processing and polymer equation development. Using fuzzy and neuro-fuzzy systems, this study investigated to present a model to predict the density of the solution of Octanol and Polyethylene Glycol. First, the databank of the dataset collections included 477 data. The data were divided into 120 test data and 357 training data for the fuzzy and neuro-fuzzy systems, and 318 training data and 159 network test data for the neuro-fuzzy system; the training data of both models were used as the inputs to make the related fuzzy inference system. The Gaussian functions were extracted for each input using network segmentation and the optimal parameters were calculated by the neural network with the hybrid algorithm. The comparison of the laboratory results with the predicted amounts by fuzzy and neuro-fuzzy systems indicated that the predicted amounts by these models are in a desirable consistency with the laboratory data and this shows the reliability of these models. The average absolute deviation of the error in fuzzy and neuro-fuzzy systems was 1.1991 and 0.0635, respectively. The results of this prediction indicate a desirable efficiency of neuro-fuzzy modeling for predicting the density of Octanol and Polyethylene Glycol solution. |
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Evaluation of sustainable landscape services based on the analytic network process (ANP)
Original Research Article
Pages 119 – 129
F. Khosravi , H. Irani Behbahani, H.Ghaffarzadeh, A. Vafaeinejad
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(752 KB)
Abstract
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Three component one-pot synthesis of some 4H-benzo[b]pyran derivatives by using dual organo modified MCM-41 as nanocatalyst
Original Research Article
Pages 130 – 136
F. Ghalambaz, A. Farhadi, A. Reza Kiasat, R. Badri
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(959 KB)
Abstract
This paper presents a feasible protocol for the preparation of new nano dual organo modified MCM-41, MCM-41-β-CD.NH2, and investigate its catalytic application for the synthesis of 4H benzo[b]pyran derivatives. The nanocomposite was succesfully characterized by FT-IR, TGA, SEM, TEM and BET techniques. These data were shown that β-CD and triethoxysilyl amine are grafted onto MCM-41. |
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Prevent of greenhouse gas emissions in aluminum smelter by carbon nanotube (Monte Carlo simulation)
Original Research Article
Pages 139– 146
M. Ameri Siahooei, Kh. Mehrani, M.Yousefi
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(1580 KB)
Abstract
Greenhouse gas emissions in aluminum smelter and separation this gases from hydrogen is very important. The gaseous constituents are carbon dioxide, sulphur dioxide and hydrogen fluoride , carbon tetrafluoride, di-carbon hexa-fluoride, silicon tetrafluoride, hydrogen sulphide, carbon disulphide, and hydrocarbons gaseous have been identified. Challenged by growing environmental concerns, the primary aluminium industry has undergone major changes over the last two decades to become a much more efficient industry with GHG emissions during the smelting process. The aluminium indndustry has been identified as a major contributor to GHG emissions and is therefore under particular scrutiny from the Intergovernmental Panel on Climate Change (IPCC), one of whose targets is to reduce these emissions by 50 to 85% by2050.This study has been conducted to figure out the adsorption and separation of greenhouse gas emissions with hydrogen on (8,8) armchair carbon nanotubes (CNTs). Lennard-Jones potential was used for gas-gas and gas-carbon nanotube interactions and the potential parameters for the carbon-gas and carbon-carbon interactions were obtained from the Lorenz-Berthelot combining rules. My calculations have shown that adsorption between hydrogen and these gases in aluminum smelter is possible and separation between studied gases in inside and first layer of outside carbon nanotube is possible |
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An experimental approach to an optimized method for producing Al2O3-coated aluminum nanopowder as a core-shell superconductor by electro explosion of wire
Original Research Article
Pages 147 – 153
M. Rostami, H. Khorsand
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(512 KB)
Abstract
The most common way to produce aluminum nanopowders is electro explosion of wire. In this procedure we just need to have available source of electrical energy. Aluminum nanopowders have a wide range of use like metallurgical or chemical industries. Al2O3 coated Aluminum nanopowders are also used as high temperature superconductors. This research is based on electrical explosion of wire by using low voltage DC current with suitable amperage. Effect of using various voltages was studied and the best parameter for it was achieved at 36 V. At the same time, ethanol as a suitable atmosphere is suggested and a very cost effective way of producing aluminum nanopowders offered which can produce 20 to 150 nanometer aluminum nanopowders. Transmission electron microscopy and dynamic light scattering were employed to analyze and measuring respectively. Also X-ray diffraction method was used to demonstrate quality of Al2O3-coated aluminum nanopowders. |
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Modeling and optimization of electromagnetic and saturated magnetic properties of polyester fabrics coated with Ag/kaolin/silica nanocomposites
Original Research Article
Pages 154 – 167
E.Zarrinabadi, R.Abghari, A.Nazari, M.Mirjalili
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(1757 KB)
Abstract
In this study, the photo-reduction method is used to synthesize a three-component nanocomposite containing Ag, Kaolin, and Silica. The values of these three components are optimized to make a central composite design. Through ultrasound and UV photo reduction, virgin polyester fabrics coated with different ratios of Silica/kaolin/Ag are evaluated for their electromagnetic and saturated magnetic properties. The fabrics are analyzed by electromagnetic reflection and electromagnetic transmission techniques as well as the vibrating sample magnetometry test, and their properties are optimized according to the response surface methodology. Detective analytical methods such as field emission scanning electronic microscopy, energy dispersive x-Ray analysis, and infrared spectroscopy are implemented on the triple nanocomposite-treated polyester fabrics. The experimental results show that the electromagnetic and saturation magnetic properties of such polyesters are significantly improved when a coating layer of the triple nanocomposite with proper concentrations of silica, kaolin and Ag is applied on the fabric surface. |
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Providing an interpretive structural model of implementation of cleaner production in the pharmaceutical industry
Original Research Article
Pages 168 – 179
M. Adelizadeh, M. Aleagha, A. Behbahaninia
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1121 KB)
Abstract
Nowadays, because of globalization, enhancement of the regulations of governmental and nongovernmental organizations and the pressure customers put on these organizations and their demand to observe environmental issues have led the organizations to examine the efforts that must be made for implementing the cleaner production approach in order to improve their economic and environmental performance. The present study has aimed to propose an interpretive structural model for the execution of the cleaner production approach in the pharmaceutical industry. The statistical population of this research has been composed of pharmaceutical companies and 9 senior managers working in these companies have been selected as experts. In the present study, first previous studies and research literature have been carefully reviewed and critical success factors of the execution of the cleaner production approach have been determined and then, the research model has been proposed using the structural modelling technique. Research results indicate that more attention must be paid to the following factors: “cleaner regulations and policies”, “cleaner strategic incentives”, “cleaner leadership and competence”, “cleaner processes” and “cleaner employees”. The findings of this research can help the senior managers of pharmaceutical companies in making better decisions and proposing strategic solutions in the field of implementing cleaner production. |
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Safranin-O dye removal from aqueous solution using super-absorbent lignin nanoparticle/polyacrylic acid hydrogel
Original Research Article
Pages 180 – 187
K.H. Didehban, S.A. Mirshokraie, J. Azimvand
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(903 KB)
Abstract
Alkali lignin (AL) modified by ethylene glycol and lignin nanoparticles (LN) was prepared through the acid precipitation technology. Lignin nanoparticle/polyacrylic acid (LN/PAA) hydrogel was prepared using copolymerization reactions.
LN and LN/PAA hydrogel were investigated using GPC, SEM, FT-IR spectroscopy, and TGA-DTG analysis. The sizes of the nanoparticles were assessed using DLS.
LN/PAA hydrogel was used to remove Safranin-O from an aqueous Solution. The optimal conditions for absorption provided at pH 7, an initial concentration of dye of 1.5 gr.L-1, and an adsorbent dosage of 0.1 gr. Also, the optimal time for LN and LN/PAA hydrogel were 100 min and 450 min, respectively. Both absorbent LN and LN/PAA hydrogel showed good agreement with the Langmuir isotherm. The maximum absorption capacities of LN and LN/PAA hydrogel were determined to be 100 mg.gr-1 and 1666.6 mg.gr-1, respectively. Both absorbent LN and LN/PAA hydrogel follow the pseudo-second kinetic model and the intraparticle diffusion model.
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Comparison of the advanced oxidation processes and adsorption with chitosan-zeolite composite in reducing the amount of airport wastes containing glycol pollution
Original Research Article
Pages 188 – 194
P. Azimi, K. Tahvildari, P. Derakhshy, F. Motiee
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(624 KB)
Abstract
Today, the increasing growth of industrial activities has led to the entry of many pollutants into water resources. Due to the toxicity of these pollutants, their removal from water resources is essential. Also, as a result of the dehydration crisis, providing highly efficient and economical solutions for the purification and reuse of water has been considered alongside the removal of pollutants from these wastewaters.
In recent years, several methods have been considered, which include the use of adsorbents, and photo catalytic materials and carbon materials, and the most common methods for the removal of water pollutants and wastewater is the use of adsorption process by adsorbents.
A group of environmental pollutants which are cationic pollutants such as ethylene glycol can be absorbed by biological material from contaminated industrial wastewaters and can also be absorbed by a variety of adsorbents. These methods are cheap and also useful. In this study, zeolite adsorbents, chitosan powder and synthesized chitosan-zeolite composite were used, and their application was studied to remove the cationic contaminants, ethylene glycol, from aqueous environments of airport's contaminated wastewaters in different conditions in a discontinuous manner.
Non-continuous adsorption experiments were conducted to examine the effect of the factors on the removal process, including the effect of contact time of absorbent with contaminant, pH, initial concentration of the pollutant and the amount of consumed adsorbent. |
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The effect of impregnated alpha-cellulose nanofibers with ciprofloxacin hydrochloride on Staphylococcus aureus in vitro
Original Research Article
Pages 195 – 202
M.F. Yazdanbakhsh, A. Rashidi, M.K. Rahimi, R. Khajavi, H. Shafaroodi
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(911 KB)
Abstract
The main objective of this analytical and descriptive study is to evaluate the effect of alpha-cellulose nanofibers impregnated with ciprofloxacin hydrochloride on a staphylococcus aureus culture. In this regard, after conducting various studies on biocompatible and natural polymers, wheat bran was selected as a cellulosic-based biocompatible agricultural waste. After alpha-cellulose extraction from wheat barn by the ultrasonic-Soxhlet method. the alpha-cellulose investigated with FTIR. FTIR spectra showed that holocellulose was largely removed during alkali treatment under ultrasonic waves. the alpha-cellulose nanofibers were prepared by employing the electrospinning technique. from which the cellulose disks were prepared. Then, these disks and paper disks (without antibiotics) were placed in 3.3% ciprofloxacin hydrochloride. The mentioned disks were placed on the Staphylococcus aureus cultured medium alongside standard disks and the results were measured as the inhibition zone after 24 hours. Both disks (alpha-cellulose nanofibers and paper) containing ciprofloxacin hydrochloride created the inhibition zone on the S. aureus medium. The concentration of ciprofloxacin hydrochloride adsorbed by cellulose was determined by comparing the effects of cellulose disks containing different concentrations of antibiotics and standard ciprofloxacin disks. |
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Enhancement of bacterial cellulose rehydration via BTCA cross-linking
Original Research Article
Pages 203 – 208
A. Meftahi, R. Khajavi, A. Rashidi, M. K. Rahimi, A. Bahador
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Abstract
Low rehydration ability of bacterial cellulose (BC) after its first drying is an unfavourable effect especially for biomedical applications. In this study, it was aimed to overcome this defect through BC cross-linking. So, 1,2,3,4-butanetetracarboxylic acid (BTCA), as a common cross-linker of cotton, was used in different concentrations (5, 10 and 20w/v %) for this purpose. BC samples were cross-linked after synthesis in their wet state. Cross-linking of BC didn’t show any significant change in XRD patterns in compare with uncross-linked (raw) samples. Meanwhile, BET surface area testing showed that the surface volume of the cross-linked sample with BTCA 20% has increased 12 times more than uncross-linked BC. Surface and cross section FESEM images showed also thepreserved structure of cross-linked BC. In addition, water absorption of cross-linked sample (BTCA 20%) was about 300% more than uncross-linked sample. Comparing them indicated that cross-linked sample had more water swelling rate and lower water release rate and finally it was concluded that cross-linked BC show a high potent for medical applications. |
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Optimal synthesis, characterization, antibacterial and anticancer assay of green synthesized nickel nanoparticles by Taxus brevifolia leaf extract
Original Research Article
Pages 209 – 223
S. Sarli, N. Ghasemi, A. Moradi
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(2235 KB)
Abstract
Nickel nanoparticles was synthesized by T. brevifolia leafs extract. This plant has promising medicinal properties for a wide range of cancer treatment. The goal was to conjugate T.brevifolia with Ni nanoparticles for enhanced anticancer effect. the effective parameters such as pH, volume of the extract, concentration of the salt solution, temperature and time were evaluated by Ultraviolet-Visible (UV–Vis) spectroscopy. According to the obtained results, reduction of nickel ions to nickel nanoparticles by T.brevifolia extract was optimum at pH=8, 2 ml of extract, 0.003M Ni(NO3)2, t=70 oC and time of 180 min. UV– visible, scanning elec tron microscope (SEM), field emission scanning electron microscope (FESEM), X-Ray Diffraction (XRD), FTIR spectroscopy and Transmission Electron Measurement (TEM) techniques were used to confirm the nanoparticles formation. Also, the antibacterial activity of T.befolia extract, nickel nanoparticles and nickel nitrate solution were tested. Their activity on Staphylococcus-aureus, Escherichia-coli and Pseudomonas-aeruginosa demonstrated that they don’t have inhibitory effect on bacterial growth; and their anticancer activity were investigations by Breast cancer cell line MCF-7. The presence of taxol in the leaves of the T.befolia extract was confirmed by HPLC. Rresults demonstrated that in thick dilute solutions, nickel nanoparticles have more anti-cancer effects compared to the pure T.befolia extracts. |
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Optimal synthesis and characterization of green synthesized silver nanoparticles by Lawsonia inermis extract
Original Research Article
Pages 224 – 229
M.H. Rousta, N. Ghasemi, M. Ramezani, T. M. Esfahani
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(1374 KB)
Abstract
In this study, ultraviolet-visible spectrophotometer (UV-Vis) was used to find the optimum conditions for silver nanoparticles synthesis by using Lawsonia inermis extract. Affective parameters such as pH, volume of extract, concentration of salt solution, reaction temperature and time have been optimized for biosynthesis of silver nanoparticle by absorving UV-Vis spectra. The maximum absorbance wavelength of silver nanoparticles was observed at 420 nm and the obtained results from the experiments in this wavelength showed that the best conditions for nanoparticles synthesis are pH of reaction = 8, 4 ml of extract, 0.003 M silver nitrate, reaction temperature= 80 0C and 70 minutes for reaction time.
The prepared nanoparticles in optimum condition, were characterized by utilizing UV-Vis spectrophotometer, Scanning electron microscope (SEM), transmission electron microscopy(TEM), X-ray diffraction(XRD) and Fourier transform infrared (FTIR) spectroscopy. By results obtained from the devices, synthesis of cubic shaped nanoparticle with an average size of 20 nm confirmed. The results of this study showed that Biological synthesis by using Lawsonia inermis extract is a very low cost method without the need for energy. |
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The effect of temperature and phosphate treatment for investigation of wear and corrosion of synthesized nano-alumina coatings through sol-gel method on Inconel 718 alloy
Original Research Article
Pages 230 – 237
A. Samaditabrizi, K. Arzani, M. Tamizifar
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Abstract
Nano-alumina particles were coated on phosphate surface of Inconel 718 alloy through sol-gel method in this study. morphological and fuzzy structure of coatings surface were conducted through X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM) analyses, respectively. Wear properties were checked using pin-on-disk corrosion. The resistance of coated samples against corrosion was investigated by electro-chemical impedance spectroscopy. XRD results of coatings thermally treated at 300, 500 and 800˚C confirmed the amorphous nature of coatings and accordingly, weak peaks of γ-phase alumina (−23) can be only seen in thermally treated coating at 800˚C. The conducted studies by FE-SEM of coatings showed that average size of particle has been in coating of 46 Nanometer and a uniform and porosity-less structure can be only seen in thermally treated at 300˚C. The obtained results of FE-SEM of coatings indicated that the best time for immersing the samples in phosphating bath includes 60 minutes. The obtained results of wear testing depicted that the beneath surface layer phosphating increases the resistance against alumina coatings corrosion. The spectroscopy results of electrochemical impedance showed that, creating Nano-alumina coating with phosphate substrate has had a significant effect on increasing corrosion resistance of Inconel 718 alloy. |
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Preparation of magnetic nano-sponge and the effect of its absorption on β-lactam drugs
Original Research Article
Pages 238 – 243
B. Asadi, N. Ghasemi, M. Rabbani, K. Mahanpoor
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(918 KB)
Abstract
The pollution of water with pharmaceutical compounds can cause problems in the ecosystem and their release into the environment may involve long-term risks such as toxicity to aquatic organisms and endocrine disruption in higher organisms. Antibiotics have special importance due to their inducing bacterial resistance. The aim of this study was to optimize the magnetic nano-sponge to adsorption of β-lactam antibiotics.
Magnetic nanoparticles were adopted for the synthesis of magnetic polymeric adsorbents, but the incorporation of magnetic nanoparticles increased the adsorption capacity of polymeric for antibiotics. In this study, we prepared magnetic sponge by lyophilizing the dispersion of CoFe2O4 nanoparticles and acrylamide for β-lactam adsorption. CoFe2O4 nanoparticles were attached on MA-PEG, enabling the magnetic property of nano-sponge. The adsorption was moderately fast and could be described by pseudo-second-order model. The as-prepared sponge can selectively absorb β-lactam antibiotic from wastewater. |
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Green synthesis and characterization of copper nanoparticles using Eryngium campestre leaf extract
Original Research Article
Pages 244 – 250
M.Khodaie, N. Ghasemi
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(1388 KB)
Abstract
Metal oxides nanoparticles are increasingly used in various fields, including medical, food, consumer, health care, and industrial purposes, due to their unique physical and chemical properties, their unique size-dependent properties make these materials efficient for many areas of human activities. So in the past few decades, Nanotechnology has become an attractive research area. Synthesis of nanoparticles by chemical and physical methods has many disadvantages, such as need advanced equipment, solution instability and use harmful and toxic chemicals compounds during the synthesis that will have many harmful effects on environment and humans. Bio synthesis of nanoparticles compared to the other synthesis routes is more efficient, because plant sources are more available and affordable in addition, compounds which are used in this method are eco-friendly and non-toxic. The present study aims to optimize and biosynthesize copper nanoparticles using an aqueous extract of Eryngium campestre (Sulang) plants and copper nitrate. Effective factors on the formation of nanoparticles, including pH, salt concentration of copper nitrate, time and temperature were studied and optimized using ultraviolet spectrophotometer. Particle size and stabilizing chemical compounds of the obtained nanoparticles were investigated by VEGA TESCAN scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), (Bruker optics Germany), X-ray diffraction spectroscopy (XRD), (Philips X-Ray Diffraction), and Energy-dispersive X-ray spectroscopy (EDX).
According to the results, the optimum conditions for synthesis of copper nanoparticles was pH = 6, t = 35 ° C for 80 minutes, and the average size of the nanoparticles was obtained between 50 - 60 nanometers. |
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Preparation of nano-cellulose/Α-Fe2O3 hybrid nanofiber for the cationic dyes removal: optimization characterization, kinetic, isotherm and error analysis
Original Research Article
Pages 251 – 261
Gh. Chizari Fard, M. Mirjalili, F. Najafi
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(1260 KB)
Abstract
In this paper, cellulose nanoparticle with the average diameter of 35.2 nm was synthesized through the hydrolysis of microcrystalline cellulose and incorporated onto the α-Fe2O3 nanofiber surface by citric acid to prepare a hybrid nanofiber. Then, the ability of the resultant nanofibers for the removal of cationic dyes was investigated. Also, the cross linking procedure with citric acid was optimized. The characterization analyses of synthesized nanofibers showed that the cellulose nanoparticles were successfully crosslinked together through the formation of ester linkages and they were deposited onto the surface of α-Fe2O3 nanofibers. A uniform distribution of cellulose nanoparticles along with some aggregations on the surface of nanofibers was observed which was depended on the citric acid content. Also, increasing the amount of citric acid resulted to increase the specific surface area values because of attaching the higher amounts of nanoparticles with high specific surface area value (480.65m2/g) onto the nanofiber surface. Furthermore, the effects of nanofiber dosage, initial dye concentration, and solution pH on the dye removal were studied. It was found that adsorption of dye process is highly pH-dependent. In order to evaluate the rate and mechanism of adsorption, the kinetic and isotherm models were studied. To do these, non-linear regression along with 3 error functions was used to determine the best fit model. It was concluded that adsorption of dyes follows with Langmuir isotherm. In addition, adsorption kinetic conforms to pseudo-second order model. |
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[2-(Sulfooxy) ethyl] sulfamic acid (SESA): an efficient heterogeneous recyclable catalyst promoted green synthesis of Β-amido carbonyl compounds derivatives by multi-component reactions (MCRs)
Original Research Article
Pages 262 – 269
M. Hadizadeh, M.H. Mosslemin, B. Sadeghi
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(560 KB)
Abstract
Easily synthesized [2-(sulfooxy) ethyl] sulfamic acid (SESA) as a novel catalyst efficiently promoted the synthesis of β-acetamido carbonyl compounds derivatives via condensation of enolizable ketones with various aryl aldehydes at room temperature conditions in acetonitrile and acetyl chloride. This research provides a new way for the synthesis of β-acetamido carbonyl compounds in good to excellent yields of products with easy work up. The catalyst could be recycled and reused several times without any loss of efficiency.
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Hibiscus sabdariffa: biocatalyst for solvent-free synthesis of dihydropyrimidinone derivatives
Original Research Article
Pages 270 – 275
N.Ghazavi,M. H. Mosslemin, R. Mohebat
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(213 KB)
Abstract
In vitro studies show Hibiscus Sabdariffa (Sorrel), an ingredient found in many herbal tea blends and other beverages, has natural and biocatalyst properties, and can be easily used as a catalyst in organic transformations. The Hibiscus Sabdariffa can be simply prepared from herbal tea in water and has played the role of solvent cum catalyst for the Biginelli reaction. Dihydropyrimidinone’s (DHPMs) are nitrogen containing heterocyclic ring which possesses biological and pharmaceutical importance. An efficient and greener synthesis of a series of DHPMs derivatives were
accomplished via three-component one-pot cyclocondensation between aromatic aldehydes, β-dicarbonyl compound
and urea/thiourea under solvent free conditions. This solvent free and eco-friendly approach has several advantages
such as being totally pollution free and having shorter time duration with excellent yields. |
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Investigation of unimolecular reaction for C–H and N–H bonds fission in aniline by calculation Arrhenius parameters with RRKM method and analysis of NBO and HOMO, LUMO orbitals
Original Research Article
Pages 276 – 284
Z. Heidarnezhad, M. Vahedpour
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(630 KB)
Abstract
The present study provides quantitative results for the rate of unimolecular Carbon–Hydrogen and Nitrogen–Hydrogen bonds fission reaction of Aniline (AN) at elevated temperatures up to 2000 K. The potential energy surface for each C–H bond fission reactions (in the Ortho, Meta and Para positions) and N–H bond fission reactions of Aniline were investigated using abinitio calculations. The geometry and vibrational frequencies of the species involved in these reactions were optimized at the MP2 level of theory, using the cc–pVDZ basis set. Since C–H bond fission channel is a barrier less reaction, it has been used variational RRKM theory to predict rate constants. By means of calculated rate constant at different temperatures, the activation energy and exponential factor were determined. The Arrhenius expression for C–H bond fission reaction of Aniline on the Ortho, Meta and Para sites and N–H bond fission reaction are obtained as : k(T)Ortho = (1.6E16)Exp(-54347.92/T), k(T)Meta = (5.9E17)Exp(-57899.44/T), k(T)Para = (3.4E17)Exp(-59336.96/T), k(T)N–H = (2.2E21)Exp(-48298.29 /T) respectively. Moreover, the effect of Amino group nucleophilic attraction and resonance with Benzene ring, molecular rotation ,natural charge, natural bond orbital (NBO), HOMO, LUMO orbital energies and tunneling effect on the rate expression have been discussed.. |
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Identification and quantitative analysis of quercetin and luteolin polyphenol in methanolic extracts of Cirsium arvence with HPLC
Original Research Article
Pages 285 – 289
A. Dehjurian, J. Lari, A. Motavalizadehkakhky
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(897 KB)
Abstract
Polyphenols are important compounds playing an important role in plants and human body. These compounds have an antioxidant role in photosynthesis and they prevent from cancer, cardiovascular disease and diabetes. Luteolin and quercetin are two flavonoid compounds. Flavonoids are found in most plants and used in the pharmaceutical industry. In this study, it was tried to measure the amounts of these two compounds in the aerial organs of C.arvence. HPLC method was used as the analyzing tool of this project. Quercetin and luteolin both are found in two samples of the plant C.arvence collected of two different parts of Iran; A (Neyshabour) and B (Boojnoord). Quercetin were (0.038, 0.113 mg/gr, respectively) and luteolin were (0.233, 0.116 mg/gr, respectively). |
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Decolourisation of the colored textile industries using a new combination of activated carbon and fiber; kinetic, thermodynamic and isotherm studies
Original Research Article
Pages 290 – 300
M. Khazravi, M. Bahmaei, M. Ebrahim Olya, S. Masoud Etezad
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(1426 KB)
Abstract
The objective of this work is the simultaneous application of activated carbon powder and synthesized fibers as appropriate adsorbents for dye removal of the colored wastewaters. In addition, the effect of different key operating parameters such as time, pH, adsorbent dosage, initial dye concentration, column height and solution flow rate were investigated for optimization of the adsorption conditions. According to kinetic studies results, pseudo second order model was found to be well compatible with the kinetic data. Furthermore, study of the absorption isotherms (Langmuir, Freundlich and Temkin) indicated the compatibility of the process with Langmuir isotherm (R2=0.9775). The investigation of the effects of thermodynamic parameters including Gibbs free energy (G), enthalpy (H) and entropy (S) in the adsorption of Reactive Blue 19 dye using activated carbon powder and fibers simultaneously indicated a spontaneous reaction and an endothermic process. |
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Identification of a method for detecting and determining mixing palm oil with cream and detection of threshold using the chemical and machine test
Original Research Article
Pages 301 – 309
M. Dehanzadeh, P. Ziarati, M. Homapour
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(716 KB)
Abstract
Due to the unique composition of milk fat, high prices and the increase in demand has always been the aim of manipulating and fraudulently substitutes. In order to identify a method for the detection of palm olein oil mixed with creamy fat for determining detection threshold, an experiment in a completely randomized design with a mixing ratio of 5, 10, 15, 25 and 50 percent of palm oil and cream was made in 2016. The results showed that the increasing of the amount of palm oil in the cream has significant effect 05/0 p < on the composition of fatty acids; increasing the proportion of mixing results in increasing of unsaturated fatty acids such as oleic acid and their total results in decreasing of fatty butyric acid as an indicator of dairy products and decreasing of the total of saturated fatty acids. The results showed that even with the addition of 50% palm oil to cream, fatty acid profiles is in accordance with the national standard within Iran. Adding the cream of 25 and 50 percent of palm oil fatty acid to cream the ratio of fatty acids C18: 2 / C8: 0 to 3 increased respectively about 3 and 7 times higher, and the ratio of C4: 0 / C16: 0, respectively reduced to about 3/2 and the half.
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Investigation of kinetics and mechanism of the sulfating roasting process of
chalcopyrite concentrate for water-leaching
Retracted by the Authors
Pages 310 – 318
Shahram Daneshpajooh, Mohammadreza Mozdianfard
Abstract
The kinetics of sulfate roasting process of chalcopyrite concentrate was investigated in the absence of mass transfer
effects in the temperature range 500 to 625 ° C. From the study of mechanism of the sulfate roasting process by thermal
analysis of TG-DSC and XRD analysis, it was observed that the production of copper sulfate starts at a temperature of
about 500 ˚C and extends to a temperature of about 580 ˚C. Subsequently, as the temperature rises, the copper sulfate is
converted to copper oxide. After the roasting tests, it was first shown that the kinetics controller of the process inside the
chalcopyrite particle is the reaction at the level of the raw materials and products, and the penetration factor is less
effective. The activation energy of the chalcopyrite sulfating reaction was 20.818 kJ/mol based on the unreacted core
kinetic model.
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QSAR study for the prediction of physico-chemical parameter of category barbiturate compounds by using descriptors structure
Original Research Article
Pages 319 – 325
E. Esmaeili, F. Shafiei
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(885 KB)
Abstract
Topological indices as molecule indices are used in quantitative studies of structure- properties. In this study the relationship between the S1K, X0, X0sol, MW, Se, Ms, BAC , BIC2, Xindex, X3A , CSI, S3K, SRW04, IDDE, nSK ,Ss , SMTIV ,GNar , TIC0, X5v , AECC and UNIP calculated by Dragon to the Polarizability (POL) of 32 barbiturates is represented. The chemical structures of the molecules were optimized using ab initio 6-31G basis sets method and Polak-Ribiere algorithm with conjugated gradient within HyperChem 8.0 environment. The multiple linear regressions (MLR) and Back ward methods (with significant at the 0.05 level) were employed to give the QSAR models. After MLR analysis, we studied the validation of linearity between the molecular descriptors in the best models for used properties. The predictive powers of the models were discussed by using the method of cross-validation. The results have shown that descriptors (S3K, SRW04, and GNar) could be efficiently used for estimating the polarizability of respect compounds. |
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Extraction water-swellable fraction of gum tragacanth for innovation in burn wound dressing
Original Research Article
Pages 326 – 334
F. Nayeb Morad, A. Rashid, R. Khajavi, M. Karim Rahimi, A. Bahador
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(904 KB)
Abstract
Gum Tragacanth (GT) obtained from Astragalus gossypinus is one of the most widely used natural gums which has found applications in many areas because of its attractive features such as biodegradability, nontoxic nature, natural availability, moisture absorption and creating a network of hydrocolloid. It also has maintenance and delivery of drugs, higher resistance to microbial attacks and long shelf-life properties. Gum Tragacanth consists two major fractions: a water-soluble part which contain tragacanthic Acid and small amount of an arabinogalactan and water insoluble part ,contain bassorin which insoluble in water, has the capacity to swell and form a gel.
In present study, the separation of tragacanthin and bassorin suggests that the two polysaccharides are in a physical mixture and not chemically bonded. Bassorin which represents 60–70% of the total gum with a molar mass of approximately 105 Da, though insoluble in water. Another small fraction,termed tragacanthin is soluble in water with a molar mass of approximately 104 Da to give a colloidal, hydrosol solution. Bassorin, a pectic component, has a chain of (1-4)-linked α-D-galacturonic acid units some of which are substituted at O-3 with β-D-xylopyranosyl units and some of these being terminated with D-Gal or L-Fuc .The solution of bassorin viscosity were very high and could not be electrospun. To improve the spin ability of bassorin, Polyethylene oxide (PEO) was blended with this polysaccharide. Preparation nanofibers of 50 wt% bassorin (extracted from gum tragacanth) has been mixed by 50 wt% polyethylene oxide and 0.01 wt% ofloxacin (Ba/PEO/Ofx) for electrospinning. Nanofibers coated on cotton gauze. The properties of Bassorin and produced nanofibers were examined via XRD, FTIR and SEM microscopy. The Antibacterial of nanofibers activity against Staphylococcus aureus as Gram-positive bacteria and Escherichia coli as a Gram-negative bacteria also were investigated. Nanofibers are capable of absorbing wound’s exocrine liquid easily due to their high specific area of nanofibers which 4 to 5% more than cotton gauzes without nanofibers. When it is turned to gel by moisture sorption, the release of loaded ofloxacin would be enhanced. The Antibacterial assay showed the cotton gauze coated with Ba/PEO/Ofx nanofibers could inhibit about 90% growth both bacterial strain. |
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Effect of substituted Mn on optical properties of indium oxide and zinc oxide
Original Research Article
Pages 335 – 340
M. M. Amiri, F. Amiri, F. Foroutan, H. Asghar Rahnamaye Aliabad
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(1047) KB)
Abstract
Improving the optical properties of materials in the industry is of particular importance. In this paper, we investigated the effect of manganese succession on indium oxide and zinc oxide. Using first-principles based on the density functional theory, the relationship between band structures and optical properties is examined. The full potential linearized augmented plane wave (FP-LAPW) method is employed accompanied by the generalized gradient approximation (GGA). Optical spectra calculations are done for the energy range 0–40 eV. The obtained results indicate that the band structure decreases for In2O3 and increases for ZnO by adding Mn. The optical results reveal that the static Dielectric function increases for In2O3 and decreases for ZnO due to the Mn dopant. It was observed that the static refractive index for doped indium oxide increased and for doped zinc oxide decreased. |
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Synthesis of porous Al2O3–SiO2 nanocomposite xerogel through a sol-gel method and its application in adsorption of heavy metalse
Original Research Article
Pages 341 – 347
Sh. Bizhanzadeh, M. Daghighi, L. Torkian
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(761) KB)
Abstract
Various methods have been presented by different researches for the synthesis of Al2O3–SiO2 nanocomposite xerogel based on its different applications in industries. In this research, a simple, economic and environmental friendly method was presented for the preparation of Al2O3–SiO2 nanocomposite xerogel using sol-gel method. The structure of prepared nanocomposites is characterized by FTIR, BET, SEM, XRD and EDX methods. To consider the effect of product calcinations on porosity, specific surface area, diameter, volume and distribution of pore size calcinated at temperatures of 600, 800 and 1200 °C, nitrogen adsorption/desorption device was used. Results from the study of isothermal charts confirm the mesoporous structure of prepared nanocomposites and their highest specific surface area among known Alumina –Silica zerogel synthesized nanocomposites. The nanocomposite can be utilized as an adsorbent due to its homogeneity and porosity. Therefore, In order to study the absorption of heavy metals, lead and nickel adsorption by nanocomposite calcinated at temperatures of 600, 800 and 1200 °C was studied in this research and atomic absorption spectrometry (AAS) was employed for the calculation of Pb (II) and Ni( II) concentrations. Results from AAS indicate that all three samples have good potentials in adsorption of mentioned cations while lead adsorption is more efficient than nickel.
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Synthesis and characterization of silver nanoparticles using Thymbra spicata L. herbal extract for removing methylene blue dye from aqueous solutions
Original Research Article
Pages 348 – 361
Tayeb AB Matin, Nahid Ghasemi, Keivan Ghodrati, Majed Ramezani
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(1556) KB)
Abstract
Nowadays silver nanoparticles are produced by different chemical methods. Which have disadvantages such as instability of the solution and also require advanced equipment for production. So, green synthesis routes have attracted the attention of researchers for producing nanoparticles that have the minimum environmental hazards and require simple equipment for production. Herbal extracts can be used as a green route to synthesize silver nanoparticles. In this work, synthesis of silver nanoparticles was carried out using Thymbra spicata L. herbal extract (with the local name of zoofai). Silver nitrate was added to the extract and the effect of silver nitrate concentration, volume of the extract, temperature and time on silver nanoparticles synthesis was investigated. The synthesized nanoparticles have been characterized by UV-Vis spectroscopy, transmission electron microscopy (TEM), XRD, DLS, scanning electron microscopy (SEM), X-ray diffraction spectroscopy (EDX), and FT-IR. At UV-Visible spectrum, the presence of a peak at 430 nm indicates the biological synthesis of this nanoparticle in the presence of extract, and TEM image showed the spherical shape for the nanoparticle. Particle size distribution and average particle size were found to be about 40 nm by DLS. XRD image confirmed face-centered cubic nanocrystals with an average size of 21.3 nm, and SEM images were also well-matched with TEM and XRD images. Many organic dyes, such as methylene blue cationic dye, are toxic, carcinogenic and non-degradable because of their complex aromatic structure and high solubility in water. Therefore, it is necessary to remove them from wastewater. In this study, the efficiency of nanoparticles in the removal of methylene blue from water was also investigated by changing some parameters such as silver nanoparticle dosage, concentration of methylene blue and time, and it was found that the removal procedure is well done. |
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INSTRUCTIONS TO THE AUTHORS |
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CONTENTS |
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