توجه: محتویات این صفحه به صورت خودکار پردازش شده و مقاله‌های نویسندگانی با تشابه اسمی، همگی در بخش یکسان نمایش داده می‌شوند.
۱Oxidative Desulfurization of model diesel on MoO3\Al2O3 Catalyst: Effect of Drying Method and Mo Loading
اطلاعات انتشار: چهاردهمین کنگره ملی مهندسی شیمی ایران، سال
تعداد صفحات: ۵
The mesoporous MoO3\γ–Al2O3 catalyst was prepared by incipient wetness impregnation method aiming to investigate the effect of drying method and molybdenum content on the catalystproperty and performance towards the oxidation of benzothiophene (BT), dibenzothiophene(DBT) and 4,6–dimethyle dibenzothiophene (4,6–DMDBT) with H2O2 for deep oxidative desulfurization of diesel. The catalyst was characterized by XRD, BET, BJH and SEM method.The catalyst with 10wt.% and 15wt.% Mo content represented same optimum performance for DBT and 4,6–DMDBT removal, but a catalyst with 10wt.% Mo showed higher efficiency than15wt.% Mo for BT conversion. The SEM images showed that use of rotary evaporator in drying step reached a more homogenous impregnation. The oxidation reactivity of different sulfur compounds was studied which followed the order of DBT>4,6–DMDBT>>BT<\div>

۲Statistical modelling and optimization of dibenzothiophene (DBT) oxidation in deep desulfurization of diesel
اطلاعات انتشار: هفتمین کنگره ملی مهندسی شیمی، سال
تعداد صفحات: ۱۰
In this research, the effects of process variables on the efficiency of DBT oxidation in the formicacid\H2O2 system for oxidative deep desulfurization of diesel are systematically evaluated by statistical modelling, analysis and optimization using response surface methodology (RSM) byimplementing the Central Composite Design (CCD). Three control variables including temperature, H2O2\sufur ratio, and catalyst dosage are investigated. A quadratic regression modelis developed to predict the yield of sulfur elimination as the model response. Analysis of varianceconfirmed that the developed model is in good agreement with the experimental results. Themodel indicates that three studied variables have significant effects on the response; however,temperature is the most significant factor. Moreover, the model suggests an important interaction between temperature and H2O2\sulfur ratio contributed to the response, which can be attributed to the thermal decomposition of H2O2 at higher temperatures and water hindrances which producedfrom oxidative desulfurization reaction. The optimization accomplished by the model shows thatthe optimal condition for maximum yield of desulfurization is obtained at high temperature (57 °C), minimum H2O2\sulfur ratio (2.5 mol\mol) and catalyst dosage of 0.82 mL in the reaction system (50 mL solution of DBT in n–hexane including 500 ppmw concentration of sulfur). Usingthese optimal values, the maximum yield of desulfurization is predicted 95% after 1 hr reaction. Inthe optimization process, minimizing H2O2\sulfur ratio and catalyst dosage for the maximum yieldof desulfurization is economically considerable. The results indicate that RSM can be applied effectively for the modelling of DBT oxidation and economical optimization for higher efficiency of deep desulfurization of model fuel.<\div>

۳On the Relationship between Metacognitive Reading Strategies, Reading Self–Efficacy, and Reading Comprehension in an Iranian EFL Setting
نویسنده(ها): ،
اطلاعات انتشار: سومین کنفرانس بین المللی پژوهشهای کاربردی در مطالعات زبان، سال
تعداد صفحات: ۱۸
The present study was conducted to investigate the relationship between metacognitive reading strategies, reading self–efficacy, and reading comprehension of Iranian EFL learners. The participants were 119 Iranian B.A. and M.A. students majoring in English at Imam Khomeini International University and Islamshahr Azad University. A Michigan test was given to the participants to determine their language proficiency and reading comprehension. Then, they were asked to respond to the two questionnaires of MARSI (Metacognitive Awareness of Reading Strategies Inventory), and RSEQ (Reading Self–Efficacy Questionnaire). To analyze the data, multiple regression analyses and correlation procedures were used. The results revealed a significant relationship between the use of reading strategies and reading comprehension. Also, a significant relationship was found between the use of reading strategies and reading self–efficacy. Moreover, findings showed a positive relationship between reading self–efficacy and reading comprehension of Iranian EFL learners. The results of the present study may be helpful for teachers, learners, and materials developers.<\div>

۴Self–Regulated Learning Strategies as Predictors of Reading Comprehension
نویسنده(ها): ،
اطلاعات انتشار: سومین کنفرانس بین المللی پژوهشهای کاربردی در مطالعات زبان، سال
تعداد صفحات: ۱۱
The present study was conducted to investigate the relationship between self–regulated learning strategies and reading comprehension of Iranian EFL learners. The participants were 119 Iranian B.A. and M.A. students majoring in English at Imam Khomeini International University and Islamshahr Azad University. Michigan Test of English Language Proficiency was given to the participants to determine their language proficiency and reading comprehension. Then, they were asked to respond to the Self–Regulation Trait Questionnaire. The result of the multiple regression analysis revealed that among six components of self–regulated learning strategies, planning and effort were two predictors of reading comprehension. The results of the present study may be helpful for teachers, learners, and materials developers<\div>
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