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کاربرد نوع شرط:
- جایگاه : پژوهشی
- مجله: Journal of Teaching Language Skills
- نوع مقاله: Journal Article
- کلمات کلیدی: EFL Teachers,Job satisfaction,Teacher Self-Efficacy,Collective teacher efficacy,teaching commitment
- چکیده:
- چکیده انگلیسی: A significant research base has increasingly substantiated that teachers are among the most significant players affecting student achievement in second language classrooms. As a result, teacher-related variables have enjoyed much research attention over the recent decades in both mainstream education and English Language Teaching (ELT). Likewise, the present study was set to test a structural model of collective teacher efficacy, teacher self-efficacy, job satisfaction, and teaching commitment, and specifically to examine the hypothesis that teaching commitment mediates the effects of collective teacher efficacy and teacher self-efficacy on job satisfaction. Using a sample of 312 Iranian EFL teachers, structural equation modeling (SEM) was conducted to establish the structural model. The findings of a confirmatory factor analysis (CFA) confirmed the fitness of both the employed scales and the structural model. The findings and implications of the present study are finally discussed.
- انتشار مقاله: 19-06-1397
- نویسندگان: Jalil Fathi,Elaheh Savadi Rostami
- مشاهده
- جایگاه : پژوهشی
- مجله: Journal of Particle Science & Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: Adsorption,Isotherm,Malachite Green,Modified perlite
- چکیده:
- چکیده انگلیسی: Adsorption of malachite green (MG) from an aqueous solution onto unexpanded perlite (UP), expanded perlite (EP) and NaOH-modified unexpanded perlite (NaOH-UP) powders has been investigated. The effects of contact time, pH, initial dye concentration, adsorbent dosage and temperature have been evaluated. The adsorbents were characterized by Brunauer-Emmett-Teller (BET) analysis, Fourier transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM). The obtained results proved that the three examined powders can be used successfully for removal of MG from aqueous solutions as low cost mineral adsorbents. The maximum adsorption capacities of UP, EP and NaOH-UP were 23.81 mg/g, 29.41 mg/g and 39.68 mg/g, respectively. Kinetic studies show that the kinetics of the MG adsorption onto the adsorbents followed the second order model. The MG equilibrium adsorption data were best described by the Langmuir isotherm model for all adsorbents.
- انتشار مقاله: 26-01-1396
- نویسندگان: Elahe Rostami,Reza Norouzbeigi,Ahmad Rahbar-Kelishami
- مشاهده
- جایگاه : پژوهشی
- مجله: Advances in Environmental Technology
- نوع مقاله: Journal Article
- کلمات کلیدی: Adsorption,Congo red,Bentonite,Langmuir,Thermally and chemically modification
- چکیده:
- چکیده انگلیسی: Raw bentonite (RB), a known low-cost versatile clay was used as an adsorbent. RB was treated thermally and chemically to increase its adsorption capacity. For thermal treatment (TTB), the bentonite was heated at 400 °C for 60 min, and for the chemical modification, its surface was treated by cetyltrimethylammonium bromide (CTAB) to prepare organo-modified bentonite (CTAB-B). The removal of Congo red dye (CR) from aqueous solution was investigated in the batch mode. The prepared adsorbents were characterized by SEM, BET, and FTIR analyses. The effects of various experimental parameters such as contact time, pH, adsorbent dosage, dye concentration and temperature were investigated. The obtained results were in good agreement with the Langmuir isotherm model, and the maximum adsorption capacity of RB, TTB and CTAB-B was 43.1, 55.86 and 116.28 mg/g, respectively. The adsorption kinetic was better described by the pseudo-second order kinetic model. The results showed that thermally or chemically modified bentonite could be proposed as a low-cost adsorbent for the removal of CR from water.
- انتشار مقاله: 01-10-1395
- نویسندگان: Elahe Rostami,Reza Norouzbeigi,Ahmad Rahbar
- مشاهده