Academic Center for Education

Tabrīz, Iran

Academic Center for Education

Tabrīz, Iran
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Mohammadi N.,Academic Center for Education | Khani H.,Academic Center for Education | Gupta V.K.,Indian Institute of Technology Roorkee | Gupta V.K.,King Fahd University of Petroleum and Minerals | And 2 more authors.
Journal of Colloid and Interface Science | Year: 2011

The mesoporous carbon CMK-3 adsorbent was prepared, characterized, and used for the removal of anionic methyl orange dye from aqueous solution. Adsorption experiments were carried out as batch studies at different contact time, pH, initial dye concentration, and salt concentration. The dye adsorption equilibrium was rapidly attained after 60. min of contact time. Removal of dye in acidic solutions was better than in basic solutions. The adsorption of dye increased with increasing initial dye concentration and salt concentration. The equilibrium data were analyzed by the Langmuir and Freundlich models, which revealed that Langmuir model was more suitable to describe the methyl orange adsorption than Freundlich model. Experimental data were analyzed using pseudo-first-order and pseudo-second-order kinetic models. It was found that kinetics followed a pseudo-second-order equation. Thermodynamic study showed that the adsorption was a spontaneous and exothermic process. © 2011 Elsevier Inc.

Gupta V.K.,Indian Institute of Technology Roorkee | Gupta V.K.,King Fahd University of Petroleum and Minerals | Ganjali M.R.,University of Tehran | Norouzi P.,University of Tehran | And 3 more authors.
Critical Reviews in Analytical Chemistry | Year: 2011

An overview of potentiometric sensors that are capable of detecting toxic heavy metal ions in environmental samples is presented and discussed. Notwithstanding the tremendous work performed so far, it is obvious that still several limitations do exist in terms of selectivity, limits of detection, dynamic ranges, applicability to specific problems, and reversibility. A survey on important advances in potentiometric sensors with regard to high selectivity, lower detection limit, fast response time, and on-line environmental analysis is presented in this review article. [Supplemental materials are available for this article. Go to the publisher's online edition of Critical Reviews in Analytical Chemistry to view the free supplemental file. © Taylor and Francis Group, LLC.

Abdolahpur Monikh F.,Khorramshahr Marine Science and Technology University | Hosseini M.,Shahid Beheshti University | Kazemzadeh Khoei J.,Academic Center for Education | Ghasemi A.F.,Khorramshahr Marine Science and Technology University
International Journal of Environmental Research | Year: 2014

In this study, three stations of the north Persian Gulf were analyzed in order to determine the effect of trophic levels on the concentration of harmful PAHs in fish and sediment. In all cases, similar distributions were observed in which benzo(a)pyrene largely predominated and benzo(b)fluoranthene and pyrene were the second major compounds in fish tissues. The predominant components of PAHs in sediment were acenaphthene, pyrene and benzo(ghi)perylene. Based on the molecular weight of PAHs, the concentrations of the compounds vary among species. Netuma bilineata, which is carnivorous, classified at a 0.49 to 3.8 trophic level and lives in association with sediment, accumulated the highest concentrations of high molecular weight PAHs, whereas L. abu, which is herbivorous and classified at a 0.2 to 2.6 trophic level, tended to accumulate low molecular weight PAHs. Comparison among the stations indicated that the fish and sediment from Tangestan estuary accumulated the highest levels of the compounds.

Mahmiani A.,Islamic Azad University | Khormali O.,Academic Center for Education | Iranmanesh A.,Tarbiat Modares University
Optoelectronics and Advanced Materials, Rapid Communications | Year: 2010

In this paper, the first type of edge-Wiener index of TUC4C8(R) nanotube is computed.

Kashef N.,University of Tehran | Djavid G.E.,Academic Center for Education | Shahbazi S.,University of Tehran
Journal of Infection in Developing Countries | Year: 2010

Background: Antibiotic resistance of urinary tract pathogens has increased worldwide. Knowledge of the antibiotic resistance patterns of uropathogens in specific geographical locations is an important factor for choosing an appropriate empirical antimicrobial treatment. The aim of this study was to provide information regarding local resistance patterns of urinary pathogens to the commonly used antibiotics in Tehran, Iran.Methodology: Urine samples collected and submitted to two pathobiology laboratories in Tehran were identified by conventional methods over a period of three years (December 2006 to May 2009). Antimicrobial resistance testing was performed by the standard disk diffusion technique in accordance with the recommendations of the Clinical and Laboratory Standards Institute.Results: Of the total 13,333 mid-stream urine samples collected from suspected cases of urinary tract infection, 840 (6.3%) were positive for pathogenic bacteria. Escherichia coli (E. coli) was the most common isolate (68.8%) followed by Proteus spp. (12.4%), and Klebsiella spp. (9.6%). E. coli isolates were mostly susceptible to nitrofurantoin (71.3%), followed by ciprofloxacin (68.1%); however, only 38.2% of E. coli isolates were susceptible to trimethoprim-sulfamethoxazole. Conclusion: Nitrofurantoin may be considered as a first-line empiric antibacterial agent for urinary tract infections in outpatients in Tehran, Iran. © 2010 Kashef et al.

Soleimani M.,Tehran University of Medical Sciences | Shams S.,Qom University of Medical Sciences | Majidzadeh-A K.,Tehran University of Medical Sciences | Majidzadeh-A K.,Academic Center for Education
Journal of Applied Microbiology | Year: 2013

Aim: The aim of this study was designing a LAMP method for the rapid detection of Brucella and development of a sensitive quantitative-LAMP (Q-LAMP) assay for quantification of brucellosis. Methods and Results: In this study for the LAMP detection of the causative agent of brucellosis, we used specifically designed primers to target the omp25 conserved gene of Brucella spp. The sensitivity of the LAMP method was evaluated by preparing serial tenfold dilution of omp25 gene containing plasmid followed by performing the LAMP reaction. To improve the assay as a quantitative test, LAMP products in the serial dilution were evaluated by Loopamp real-time turbidimeter system and then standard curve was generated by plotting time threshold values against log of copy number. The assay specificity was evaluated using Brucella genomic DNA and a panel containing genomes of 11 gram-positive and gram-negative organisms. The LAMP assay was highly specific and no amplification products were observed from the non-Brucella organisms. The test sensitivity for visual detection of turbidity or fluorescent colour change and also agarose gel electrophoresis was 560 ng and 5·6 ng, respectively. The lower limit of detection was 17 copies of the gene that could be detected in 50 min. Conclusions: The results of this study indicated that the LAMP assay is a simple, rapid, sensitive and specific technique for detection of Brucella spp. that may improve diagnostic potential in clinical laboratories. Significance and Impact of the Study: The LAMP assay because of the simplicity and low cost can be preferred to other molecular methods in the diagnosis of infectious diseases. © 2013 The Society for Applied Microbiology.

Rofouei M.K.,University of Tehran | Rezaei A.,University of Tehran | Masteri-Farahani M.,University of Tehran | Khani H.,Academic Center for Education
Analytical Methods | Year: 2012

In this paper, new modified magnetite nanoparticles functionalized with triazene groups were designed and synthesized for extraction/preconcentration of sub-ppb level of mercury ions in water and fish samples prior to its determination with inductively coupled plasma optical emission spectrometry (ICP-OES). In the separation process, aqueous solution of Hg 2+ ions was mixed with 150 mg of Fe 3O 4 magnetite nanoparticles modified with 1-(p-acetyl phenyl)-3-(o-ethoxy phenyl) triazene (AET) and then external magnetic field was applied for isolation of magnetite nanoparticles containing mercury ions. Experimental conditions for effective adsorption including pH, sample volume, eluent concentration and existing co-existing ions have been studied and established. Under the optimal extraction and preconcentration conditions, the limit of detection (LOD) of 0.04 ng mL -1 and the relative standard deviation (R.S.D) of 2.09% for five replicate extractions and measurements of 10 μg of Hg 2+ ion in 1000 mL water solution were achieved by ICP-OES. The sorption capacity of functionalized Fe 3O 4 magnetite nanoparticles under optimum conditions has been found to be 10.26 mg of mercury ion per gram at pH 7 with the preconcentration factor of 500 (2 mL of elution for a 1000 mL sample volume). Standard solutions containing Hg 2+ in the concentration range of 0.2-200 ng mL -1 were examined by the proposed procedure and it was observed that calibration curve was linear in this range (R 2 = 0.999). The special advantages of the proposed method are high enrichment factor, fast separation and low detection limits compared with other methods. © 2012 The Royal Society of Chemistry.

Rezaei A.,University of Tehran | Khani H.,Academic Center for Education | Masteri-Farahani M.,University of Tehran | Rofouei M.K.,University of Tehran
Analytical Methods | Year: 2012

New modified magnetic nanoparticles functionalized with salicylaldehyde groups were designed and synthesized to produce a Schiff base-sorbent for extraction/preconcentration of sub-ppb levels of uranium ions in water samples prior to their determination by inductively coupled plasma optical emission spectrometry (ICP-OES). In the separation process, an aqueous solution of U(vi) ions was mixed with 100 mg of functionalized Fe3O4 magnetic nanoparticles with salicylaldehyde groups (Sal-APS-FMNPs) and then an external magnetic field was applied for isolation of Sal-APS-FMNPs containing uranium ions. Experimental conditions for an effective adsorption including pH, sample volume, eluent concentration, and presence of co-existing ions have been studied and established. Under the optimal extraction and preconcentration conditions, a limit of detection (LOD) of 0.24 ng mL-1 and a relative standard deviation (RSD) of 1.5% (n = 8) were achieved by ICP-OES. The analytical curve was linear in the range 1-5000 ng mL-1. Under the optimum conditions, the sorption capacity of Sal-APS-FMNPs has been found to be 49 mg of U(vi) ions per gram at pH 7 with a preconcentration factor of 1000 (1 mL of elution for a 1000 mL sample volume). The proposed method is characterized with high enrichment factor, easy preparation and regeneration of sorbent, short time of sample pretreatment, fast and really clean separation, high extraction yields, wide linear curve, and low detection limits. Finally, the proposed method was successfully used for extraction, preconcentration, and determination of U(vi) ions in some real samples. © 2012 The Royal Society of Chemistry.

Mohammadi S.,Shahid Beheshti University | Dehghani M.,Shahid Beheshti University | Sharpe L.,University of Sydney | Heidari M.,Shahid Beheshti University | And 2 more authors.
Pain | Year: 2012

Despite increasing interest in the attentional biases of pain patients towards pain-related stimuli, there have been no investigations of whether the main caregivers of chronic pain patients also selectively attend to pain-related information. We compared the attentional biases to painful or happy faces of 120 chronic pain patients, 118 caregivers, and 50 controls. Analyses found that both patients and caregivers demonstrated biases towards painful faces that were not observed in control participants or to happy faces. Those patients and caregivers who were high in fear of pain demonstrated greater biases than those low in fear of pain, and the biases of the high-in-fear-of-pain group differed significantly from zero. When sub-groups of caregivers were compared, it was found that biases towards painful faces were not observed for those caregivers who accurately identified the level of pain the patient currently reported. In contrast, those caregivers who overestimated or underestimated the patients' pain demonstrated biases that were significantly greater than zero. These results add to the growing weight of evidence suggesting that biases towards pain-related stimuli are observed in chronic pain patients, but that the nature of the stimuli is important. In addition, the results suggest that caregivers, particularly those who either under- or overestimate the level of pain that the patient reports, also demonstrate similar biases. Future research should investigate the links between caregivers' biases and the way in which caregivers respond to pain. © 2011 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

Shahrezaei F.,Academic Center for Education | Mansouri Y.,Islamic Azad University at Īlām | Zinatizadeh A.A.L.,Razi University | Akhbari A.,Razi University | Akhbari A.,Islamic Azad University at Kermānshāh
Powder Technology | Year: 2012

The photocatalytic oxidation and mineralization of petroleum refinery wastewater in aqueous catalyst suspensions of titanium dioxide (TiO 2), Degussa P25 (80% anatase, 20% rutile), were carried out in a batch circulating photocatalytic reactor. The experiments were conducted based on a central composite design (CCD) and analyzed using response surface methodology (RSM). In order to analyze the process, four significant variables viz. pH (2-10), catalyst concentration (0-200mg/l), temperature (22.5-52.5°C), and reaction time (30-150min) and TCOD removal as the process response were studied. From the data derived from the factorial design, the ANOVA analysis revealed that the first-order effects of reaction time, pH, temperature and catalyst concentration and second-order effect of pH, catalyst concentration and temperature produce the main effect on TCOD removal efficiency. A maximum reduction in TCOD of more than 83% was achieved at the optimum conditions (pH of 4, catalyst concentration of 100mg/l, temperature of 45°C and reaction time of 120min). The reaction kinetics showed that reactive activation energy for TCOD conversion was calculated to be 19.34kJ/mol. © 2012 Elsevier B.V.

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