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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.

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.

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.

Sani S.R.,Islamic Azad University at Roudehen
Chinese Physics B | Year: 2014

The optoelectronic properties of n-TiO2NW/p-Si heterojunction fabricated by depositing TiO2 nanowires on a p-Si substrate are studied. Under excitation at a wavelength of 370 nm, the TiO2 nanowires produce a light emission at 435 nm due to the emission of free excitons. The I - V characteristics are measured to investigate the heterojunction effects under the dark environment and ultraviolet (UV) illumination. n-TiO2NW/p-Si has a p - n junction formed in the n-TiO2/p-Si heterojunction. TiO2NW/Si photodiode produces a photocurrent larger than dark current under UV illumination. It is observed that UV photons are absorbed in TiO2 and the heterojunction shows a 0.034-A/W responsivity at 4-V reverse bias. © 2014 Chinese Physical Society and IOP Publishing Ltd.

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.

Rad A.G.,Islamic Azad University at Roudehen | Abbasi H.,Islamic Azad University at Tehran | Afzali M.H.,Islamic Azad University at Tehran
Physics Procedia | Year: 2011

In this paper we report the synthesis of gold nanoparticles during laser ablation of a metal gold plate in distilled water. The experiments were performed with a first harmonic (1064 nm, 6 ns, 10 Hz) output of a Nd:YAG laser varying the operative fluency between 5 Jcm -2 and 15 Jcm -2. The results indicate that gold nanoparticles are synthesized at room temperature.In this paper we give an overview of the properties of gold relevant to its potential application in molecular-scale devices absorption spectroscopy and Transmission Electron Microscopy (TEM) were employed to determine the optical properties and size of gold nanoparticles. And novel applications of gold nanoparticles have been studied in various fields. © 2011 Published by Elsevier B.V.

Shariat A.,University Putra Malaysia | Kargarfard M.,University of Isfahan | Danaee M.,Islamic Azad University at Roudehen | Tamrin S.B.M.,University Putra Malaysia
Journal of Strength and Conditioning Research | Year: 2015

Shariat, A, Kargarfard, M, Danaee, M, and Bahri Mohd Tamrin, S. Intensive resistance exercise and circadian salivary testosterone concentrations among young male recreational lifters. J Strength Cond Res 29(1): 151-158, 2015-Strength and morphological adaptations to resistance exercise are mediated in part by anabolic hormones such as testosterone, yet the time course of variability in circadian hormone concentrations is not well characterized. This study, investigated how the circadian rhythm of salivary testosterone is altered by resistance exercise in young men. Twenty healthy young male recreational lifters (age, 18.0 ± 1.3 years) with 2 years of experience in weightlifting were recruited. A randomized controlled trial was conducted, and subjects were randomly assigned to either the resistance exercise group (n = 10), who completed a series of resistance exercise (3 times a week, in the afternoon, 6-7 repetitions, at 85% of 1 repetition maximum for 3 weeks), or a control group (n = 10), who did not exercise during the 3 weeks. Before and after the study, an unstimulated saliva sample (2 ml) was taken every 2 hours for a maximum of 16 hours during each day. A significant decrease was observed in the resistance exercise (44.2%, p = 0.001) and control group (46.1%, p = 0.001) for salivary testosterone at each time point compared with baseline (p = 0.001). There was also no significant difference between the exercise and resting conditions in both groups for salivary testosterone (p . 0.05), except a significantly higher increase by 38.4% vs. 20.02% (p = 0.001), at 1730 hours during exercise sessions in the resistance exercise group compared with the control group. Resistance exercise has no noteworthy effect on circadian secretion of salivary testosterone throughout the 16 waking hours. These results indicate that athletes can undertake resistance exercise in either the morning or afternoon with the knowledge that a similar testosterone response can be expected regardless of the time of day. © 2015 National Strength and Conditioning Association.

Fazelpour F.,Islamic Azad University at Roudehen | Vafaeipour M.,Islamic Azad University at South Tehran | Rahbari O.,Islamic Azad University at South Tehran | Rosen M.A.,University of Ontario Institute of Technology
Energy Conversion and Management | Year: 2014

Widespread application of plug-in hybrid electric vehicles (PHEVs) as an important part of smart grids requires drivers and power grid constraints to be satisfied simultaneously. We address these two challenges with the presence of renewable energy and charging rate optimization in the current paper. First optimal sizing and siting for installation of a distributed generation (DG) system is performed through the grid considering power loss minimization and voltage enhancement. Due to its benefits, the obtained optimum site is considered as the optimum location for constructing a movie theater complex equipped with a PHEV parking lot. To satisfy the obtained size of DG, an on-grid hybrid renewable energy system (HRES) is chosen. In the next set of optimizations, optimal sizing of the HRES is performed to minimize the energy cost and to find the best number of decision variables, which are the number of the system's components. Eventually, considering demand uncertainties due to the unpredictability of the arrival and departure times of the vehicles, time-dependent charging rate optimizations of the PHEVs are performed in 1 h intervals for the 24-h of a day. All optimization problems are performed using genetic algorithms (GAs). The outcome of the proposed optimization sets can be considered as design steps of an efficient grid-friendly parking lot of PHEVs. The results indicate a reduction in real power losses and improvement in the voltage profile through the distribution line. They also show the competence of the utilized energy delivery method in making intelligent time-dependent decisions in off-peak and on-peak times for smart parking lots. © 2013 Elsevier Ltd. All rights reserved.

Tafvizi F.,Parand Branch | Fard Z.T.,Islamic Azad University at Roudehen
Asian Pacific Journal of Cancer Prevention | Year: 2014

Background: The association of colorectal cancer with human cytomegalovirus (HCMV) is a controversial issue in cancer research. This study aimed to identify the HCMV virus in colorectal cancer tissues and to investigate the association of HCMV with colorectal cancer. In this study, 50 cancer tissue samples and 50 samples without colon cancer were studied in order to identify the HCMV virus through nested-polymerase chain reaction. The virus was identified in 15 cases of colorectal cancer tissues (15/50) and in 5 cases of normal tissues (5/50). Eight cases of adenocarcinoma tissues were in a moderately differentiated stage, and 7 cases had well-differentiated stage tissues that were positive for viral DNA. The findings were statistically evaluated at a significance level of p<0.05. The HCMV virus could play a role in creating malignancy and the progress of cancer through the process of oncomodulation.

Shariati M.,Islamic Azad University at Roudehen
Applied Physics A: Materials Science and Processing | Year: 2014

The growth of pyramidal and triangular beaded In2O3 nanocrystal chains by using oxygen-assisted thermal evaporation, substrate accommodation and condensation method has been articulated. Self-assembled In2O3 nanocrystal chains have been synthesized by the vapor–solid (VS) and vapor–liquid–solid (VLS) growth mechanism and also through controlling the kinetics factors (saturation ratio). A periodical one-dimensional (1-D) and persistent (0-D) growth was proposed to explain the formation of lateral nanostructures, and this formation aspect was ascribed to the alternate 1-D and 0-D growth. Preparing the needed growth factor, the In2O3 nanocrystal chains extended to several micrometers. The growth mechanism analysis was useful to realize the relation between the kinetics factors and the complex nanostructure. The morphology and size of nanocrystals intensively were changed by oxygen concentration and led to interesting photoluminescence property. © 2014, Springer-Verlag Berlin Heidelberg.

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