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Shariati M.,Islamic Azad University at Roudehen
International Journal of Modern Physics B | Year: 2015

Indium oxide (In2O3) pyramidal nano and microstructures were prepared by a thermal evaporation and condensation method. The preannealing step affected the nanostructures morphologies and their sensing capability. The nanosize structures have been fabricated in nucleated preorganized situation. By changing from prepared sites to undesired sites, the morphology was deteriorated. The synthesized In2O3 structures were characterized by field emission scanning electron microscopy (FESEM) and the X-ray diffraction (XRD) measurements. The FESEM images showed that nanostructures with 100-250 nm in size were fabricated. The XRD patterns indicated that most of the samples are crystalline. Then, the fabricated structures were investigated for H2S gas sensing. The nanocrystal pyramids were found to be sensitive to as low as 100 ppb of H2S gas at room temperature and microcrystal ones to 300 ppb. The nanopyramids demonstrated that they were very sensitive to gas presence and their response and recovery time were in a few seconds. © 2015 World Scientific Publishing Company. Source


Keihan A.H.,Baqiyatallah Medical Sciences University | Keihan A.H.,University of Tehran | Sajjadi S.,Islamic Azad University at Roudehen
Electrochimica Acta | Year: 2013

This paper reports the greatly improved electrochemical properties of Prussian blue/carbon nanotubes (PB/CNTs) modified glassy carbon electrode via a room temperature ionic liquid (RTIL) treatment. Firstly, the GC electrodes were modified with nanocomposites of RTIL/CNTs. Then, the PB nanoparticles were electrodeposited onto the modified electrode surface. Compared with the PB/CNTs/GC, the PB/RTIL/CNTs/GC electrodes showed higher PB surface concentration value of 2.42 × 10-9 mol cm-2, indicating that PB deposition efficiency was improved by 1.8 fold. The apparent diffusion coefficient for K+ displayed value of 5.77 × 10 -11 cm2 s-1, which was one order of magnitude higher than that in the absence of RTIL. PB/RTIL/CNTs/GC modified electrodes showed higher electron transfer rate of 2.44 s-1 (2.35 times as much as that of PB/CNTs/GC electrodes). RTIL modified electrodes also displayed high sensitivity toward H2O2 reduction (185.90 μA mM -1 cm-2) with low detection limit of 0.49 μM. The RTIL modified electrodes stored dry at room temperature preserved almost 100% of their initial currents over a period of 1 month, a useful property for commercial applications. © 2013 Elsevier Ltd. Source


Naeini J.,Islamic Azad University at Roudehen
International Journal of Applied Linguistics and English Literature | Year: 2015

The aim of this study was to examine and compare the impact of two Dynamic Assessment (DA) approaches, that is, Feuerstein’s Mediated Learning Experience (MLE) and Brown’s Graduated Prompt (GP) on Iranian EFL learners’ reading comprehension. Therefore, a mixed methods approach consisting of a semi-structured interview, a pretest, an intervention program, a posttest, and a transfer test was applied to assess and compare the efficacy of two DA approaches. One hundred and two EFL learners taking a General English course at Islamic Azad University were assigned to two experimental groups (MLEG and GPG) and one comparison group (CG). The participants in the MLEG took part in the MLE, and the participants in the GPG participated in the GP intervention program. The results of the qualitative as well as the aggregate and disaggregated quantitative data analyses indicated that both intervention approaches of DA were effective in enhancing the learners’ reading comprehension. © Australian International Academic Centre, Australia. Source


Darjazi B.B.,Islamic Azad University at Roudehen
Journal of Medicinal Plants Research | Year: 2011

Traditional hydrodistillation (HD) and ultrasound-assisted extraction method (UAE) have been compared and evaluated for their quantitative and qualitative compositions of the isolated essential oil from fresh page mandarin flowers. Thirty-eight flower components and twenty-nine flower components in the UAE and HD method, respectively including: aldehydes, alcohols, ketons, monoterpenes, sesquiterpenes and other components were indentified and quantified. The major flavor components of oil obtained by UAE were β-sinensal, α-sinensal, linalool, limonene, sabinene, ocimene, (z)-β-farnesene and E,E-α-farnesene. The major flavor components of oil obtained by HD were β-sinensal, α-sinensal, linalool, limonene, sabinene, ocimene and terpinene-4-ol. The UAE method offers important advantages over HD method, namely: provides a higher amount of oxygenated compounds. It offers also the possibility for a better reproduction of natural aroma of the essential oil from page mandarin flowers than the HD method. UAE method showed the highest content of aldehydes and alcohols. Since the aldehydes and alcohols content of citrus oil is considered as one of the more important indicators of high quality, method apparently has a profound influence on Page Mandarin oil quality. © 2011 Academic Journals. Source


The effects of rootstock on the volatile flavor components of page mandarin flower and leaf were investigated in this study. Flower flavor components were extracted by using ultrasound(US) water bath apparatus and eluted by n-pentane: diethylether(1:2) solvent and then analyzed by GC-FID and GC-MS. Leaf flavor components were extracted by using water distillation method and eluted by using n-hexane solvent and then analyzed by GC-FID and GC-MS. Fifty-two flower components and, sixty-nine leaf components including: aldehydes, alcohols, esters, ketones, monoterpenes, sesquiterpenes and other components were identified and quantified. The major flavor components were linalool, limonene, ocimene, α -pinene, sabinene and myrcene. The flower and leaf oil from plants grown on Swingle Citrumelo and Yuzu showed the highest content of aldehydes. Since the aldehyde content of citrus oil is considered one of the more important indicators of high quality, rootstock apparently has a profound influence on Page mandarin flower and leaf oil quality. ©2011 Academic Journals. Source

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