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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Journal of Applied Research in Water and Wastewater
- نوع مقاله: Journal Article
- کلمات کلیدی: partnership model,Ratio – trade system Ant Colony Optimization Theory of cooperative game
- چکیده:
- چکیده انگلیسی: One of the main problems in the quality control of rivers is the high control cost imposed upon pollutant units. The cooperative policy approach in the treatment process between two or more pollutant units is a new and economic perspective in the environmental management of catchment basins. Origins of large amounts pollutants which require a high cost to control pollution are trying to start partnerships with smaller units in establishing joint refineries in order to reduce their own and the whole system's costs. In this study, considering the one way direction of the river's water, the Streeter – Phelps equations were used to simulate the river. The Ant Colony Optimization was used as an efficiency model in order to acquire the best scenario of cooperation based on the maximum elimination of pollution and reduction of treatment costs without straying from the river's quality standards. Also the ratio – trade system was used for commercial purposes. After this the cost of the depleting units was split evenly between them using the cooperative game theory. The efficiency of the model was evaluated by qualitative and quantitative analysis of the Zarjub River in Gilan province of Iran. Three main scenarios were taken to mind for cooperative trading to take place. Carrying out the trade – partnership model could play positively large role in sufficing the quality the control of river water.
- انتشار مقاله: 25-11-1392
- نویسندگان: Seyed Masoud Tayefeh Cheraghali,Amin Sarang,Mohammad Ali Zahed,Hossein Vahidi,Moazameh Akbari
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Pharmaceutical Sciences
- نوع مقاله: Journal Article
- کلمات کلیدی: Cell culture,Peganum harmala,Arbutin,Biotransformation,Pycnocycla spinosa,Varthemia persica
- چکیده:
- چکیده انگلیسی: Cell cultures of Varthemia persica, Peganum harmala and Pycnocycla spinosa have been studied to evaluate their abilities to bioconvert exogenous hydroquinone. Arbutin is an important substance that has several pharmaceutical applications; therefore, we have established V. persica and P. spinosa cultures which seem to be able to metabolize hydroquinone. Callus cultures of V. persica were established from seedlings, and healthy suspensions were grown using Murashige and Skoog medium supplemented with 2,4-D and kinetin. Exogenous hydroquinone was fed to cell suspension cultures and biotransformation reactions were detected over 24 h of incubation. The cultures then extracted with methanol and extracts subjected to TLC and HPLC analysis. The V. persica and P. spinosa cultured cells in this study seem to exhibit an ability in the glucosylation of hydroquinone to arbutin. No conversion was observed with P. harmala cell suspension cultures. The ability of cultured plant cells for biotransformation of substrates appears to be depended on the culture strains.
- انتشار مقاله: 20-04-1384
- نویسندگان: Gholamreza Asghari,Aliakbar Ihsanpour,Azam Akbari
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Chemistry and Chemical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Graphene Oxide,Oxidative desulfurization,Dibenzothiophene,Porous materials,SBA-15,Heteropoly acids,UiO-66
- چکیده:
- چکیده انگلیسی: Three novel heterogeneous catalysts were prepared by immobilization of a synthesized cesium salt of 4-tungsto-8-molybdophosphoric acid (abbreviated as CW4Mo8) on well prepared and modified support materials of UiO-66, microsphere SBA-15 and Graphene Oxide (GO). The aim of this work was the investigation of the support effects on the Oxidative DeSulfurization (ODS) performance under a similar condition. These catalysts were characterized using FTIR, XRD, BET, BJH, N2 adsorption-desorption, SEM, and EDX methods. The Cs modification was performed to have an insoluble CW4Mo8 on the support materials. The Keggin structure of the synthesized CW4Mo8 and well immobilization on the supports were confirmed by the characterization results. A comparative examination was performed on the capability of these nanocomposites as catalyst-adsorbent in the ODS process. Dibenzothiophene (DBT) in n-hexane was used as an oil model. The examination results indicated the special impact of the support type on the catalyst design; High surface area and porosity, and functional group type significantly affected the efficiency of DBT oxidation and adsorption of DBTO2 from fuel by these catalysts. The maximum removal of 100 and 99% of DBT was achieved using CW4Mo8 supported on mesoporous SBA-15 (after 60 min) and UiO-66 (after 120 min) respectively. Furthermore, the best catalyst could be reused four times without a remarkable decrease in activity.
- انتشار مقاله: 27-01-1398
- نویسندگان: Azam Akbari,Hanieh Fakhri
- مشاهده
- جایگاه : پژوهشی
- مجله: Iranian Journal of Chemistry and Chemical Engineering
- نوع مقاله: Journal Article
- کلمات کلیدی: Catalyst,Ionic Liquid,Oxidative desulfurization,Carboxylic acid,Thiophenic compounds
- چکیده:
- چکیده انگلیسی: Inexpensive and low-viscosity Protic Acidic Ionic Liquids (PAILs) of N-metheyl-2-pyrrolidone formate, acetate, and propionate abbreviated as [Hnmp][HCOO], [Hnmp][CH3COO] and [Hnmp][CH3CH2COO] respectively, were prepared and characterized by FT-IR and H-NMR. Deep oxidative and extractive desulfurization of a simulated oil and a real diesel containing 1000 ppmw sulfur were studied under the catalysis of the proposed PAILs without additional carboxylic acid and extraction solvent in the system. The desulfurization efficiency in this study was influenced by both amounts of PAILs and concentration of the produced peroxy acids from H2O2. Comparing to [Hnmp][HCOO], [Hnmp][CH3COO] and [Hnmp][CH3CH2COO] had a relatively higher extraction ability however the weaker acidic properties of them resulted in a lower activation of H2O2 to produce peroxy acids and finally led to lower oxidative desulfurization (ODS) efficiency in the same condition. Additionally, the neutralization reaction may not be efficiently gone to the right hand by weaker acids. The effects of the main process variables were studied in detail. The highest desulfurization yield of 97% for BT and 99% for DBT and 4,6-DMDBT, were achieved using [Hnmp][HCOO] in the ODS system at a temperature of 40 °C, H2O2/sulfur molar ratio of 10, VPAIL/Voil of 0.2, and a reaction time of 90 min. The immiscibility of the proposed PAILs in this study with the oil phase caused the easy separation of them after desulfurization. The possible ODS pathway was also proposed.
- انتشار مقاله: 03-09-1397
- نویسندگان: Azam Akbari,Hojatollah Haji Andevary
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Modern Research in English Language Studies
- نوع مقاله: Journal Article
- کلمات کلیدی: Reading Comprehension,self-regulated learning strategies
- چکیده: پژوهش کنونی با هدف بررسی ربطه بین استراتژی های یادگیری خود تنظیم و درک مطلب فراگیران ایرانی زبان انگلیسی انجام شد. شرکت کنندگان در این پژوهش تعداد119 دانشجوی زبان انگلیسی در مقاطع کارشناسی و کارشناسی ارشد در دانشگاه بین المللی امام خمینی قزوین و دانشگاه آزاد واحد اسلامشهربودند. برای تعیین توانش زبانی فراگیران و نیز توان درک مطلب آنان، از آزمون توانش میشیگان استفاده شد. سپس از شرکت کنندگان در پژوهش خواسته شد به پرشسنامه استراتژی های یادگیری خود تنظیم پاسخ دهند. داده های بدست آمده با استفاده از فرایند رگراسون چندگانه مرحله ای مورد پردازش قرار گرفت. نتایج نشان داد از میان شش بخش استراتژی های یادگیری خود تنظیم، فقط بخش های برنامه ریزی و تلاش بطور معنی داری توان درک مطب را پیش بینی می کردند. یافته های این پژوهش می تواند برای فراگیران، آموزگاران و نیز نگارندگان مطالب درسی کاربرد داشته باشد.
- چکیده انگلیسی: The present study was conducted to investigate the relationship between self-regulated learning strategies and reading comprehension of Iranian EFL learners. The participants of the study were 119 Iranian B.A. and M.A. students majoring in English at Imam Khomeini International University in Qazvin and Islamshahr Azad University. The Michigan Test of English Language Proficiency was given to the participants to determine their language proficiency and reading comprehension. Then, the participants were asked to respond to the Self-Regulation Trait Questionnaire. The obtained data were analyzed using a stepwise multiple regression analysis. The results revealed that from among the six components of self-regulated learning strategies, only planning and effort components were significant predictors of reading comprehension. The results of the present study may be helpful for teachers, learners, and materials developers.
- انتشار مقاله: 04-02-1396
- نویسندگان: Abbas Ali Zarei,Rajab Esfandiari,Azam Akbari
- مشاهده
- جایگاه : پژوهشی
- مجله: Asia Pacific Journal of Medical Toxicology
- نوع مقاله: Journal Article
- کلمات کلیدی: Iran,Amphetamines,High Pressure Liquid Chromatography,N-Methyl-3,4-methylenedioxyamphetamine,Street Drugs
- چکیده:
- چکیده انگلیسی: Background:Ecstasy, mainly composed of 3,4-methylenedioxymethamphetamine (MDMA), is one of the most popular addictive synthetic drugs. This study was aimed to investigate the amount of MDMA in the ecstasy tablets seized in West Azerbaijan province, northwest Iran and also to assess the relationship between the physicochemical and morphological characteristics of the tablets.
Methods: MDMA content of ecstasy tablets was analyzed using high-performance liquid chromatography method. Flow rate was 3 mL/min and mobile phase consisted of a mixture of acetonitrile and water containing triethylamine (pH = 3.2). The fluorescence spectrophotometer detector set at an excitation and emission wavelength of 220 and 306 nm, respectively. The retention time of ecstasy on this system was 2.2 minutes. The calibration curve was linear (R2= 0.999) over the concentrations ranging from 0.2 to 2 µg/ml. The limit of detection and the limit of quantitation were found to be 0.06 µg/L and 0.19 µg/L, respectively with six times repetition.
Results: In this study, 85 ecstasy tablets were analyzed. Mean weight of the tablets was 275.6 ± 70.4 (range: 158.5-403.3) mg. Mean MDMA content of the tablets was 30.53 ± 23.23 (range: 0.05-70.7) mg. The tablets were classified into 8 groups based on their morphological features (color and logo). Considering the tablet groups, physicochemical features of the tablets (weight, MDMA content, and MDMA to weight ratio) were significantly different (P < 0.001). Correlation analysis showed that the MDMA content and weight of tablets were significantly correlated (P = 0.04).
Conclusion: There is variability in the physicochemical properties of ecstasy tablets available in the black market for illicit drugs in northwest Iran. This variability may potentially put abusers at increased risk of overdose due to inadvertent excess ingestion of the tablets to achieve desired effects and also experiencing more harm due to tablets adulterants.- انتشار مقاله: 10-03-1393
- نویسندگان: Reza Ghafari,Amir Heydari,Mohammad Reza Vardast,Azam Akbari
- مشاهده