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151.
Fatemeh Baghaei Ravari Athareh Dadgarinezhad 《Protection of Metals and Physical Chemistry of Surfaces》2012,48(2):265-269
The effect of thiourea on electrochemical corrosion behavior of mild steel was investigated in 0.5M HCl solution at room temperature
by electrochemical impedance spectroscopy (AC Impedance) and Tafel polarization (DC Polarization) methods. The results show
that thiourea act as mixed type inhibitor. The inhibition efficiency obtained from AC Impedance and DC polarization methods
are in good agreement. The Nyquist plots show that the corrosion behavior of mild steel in 0.5M HCl solution in the absence
and in the presence of thiourea, consist a simple capacitive loop. Changes in impedance parameters (Rct and Cdl) are indicative of adsorption of thiourea on the metal surface, leading to the formation of protective film. Thiourea is
found to adsorb on mild steel surface steel in 0.5M HCl solution, according to the Langmuir adsorption isotherm. 相似文献
152.
Faghihi R Mehdizadeh S Sina S Alizadeh FN Zeinali B Kamyab GR Aghevlian S Khorramdel H Namazi I Heirani M Moshkriz M Mahani H Sharifzadeh M 《Radiation protection dosimetry》2012,150(1):55-59
Radiographic imaging has a significant role in the timely diagnosis of the diseases of neonates in intensive care units. The estimation of the dose received by the infants undergoing radiographic examination is of great importance, due to greater more radiosensitivity and longer life expectancy of the neonates and premature babies. In this study, the values of entrance skin dose (ESD), dose area products (DAPs), energy imparted (EI), whole-body dose, effective dose and risk of childhood cancer were estimated using three methods including direct method [using thermoluminescence dosimetry (TLD) chips], indirect method (using tube output) and Monte Carlo (MC) method (using MCNP4C code). In the first step, the ESD of the neonates was directly measured using TLD-100 chips. Fifty neonates, mostly premature, with different weights and gestational ages in five hospitals mostly suffering from respiratory distress syndrome and pneumonia were involved in this study. In the second step, the values of ESD to neonates were indirectly obtained from the tube output in different imaging techniques. The imaging room, incubator, neonates and other components were then simulated in order to obtain the ESD values using the MCNP4C code. Finally, the values of ESD assessed by the three methods were used for calculation of DAP, EI, whole-body dose, effective dose and risk of childhood cancer. The results indicate that the mean ESD per radiograph estimated by the direct, indirect and MC methods are 56.6±4.1, 50.1±3.1 and 54.5±3.3 μGy, respectively. The mean risk of childhood cancer estimated in this study varied between 4.21×10(-7) and 2.72×10(-6). 相似文献
153.
Zinab Ghasemi Ahmad Seif Temer S. Ahmadi Behroze Zargar Fatemeh Rashidi Goodarz M. Rouzbahani 《Advanced Powder Technology》2012,23(2):148-156
Titanium dioxide nanocrystals were employed, for the first time, for the sorption of Hg(II) ions from aqueous solutions. The effects of varying parameters such as pH, temperature, initial metal concentration, and contact time on the adsorption process were examined. Adsorption equilibrium was established in 420 min and the maximum adsorption of Hg(II) on the TiO2 was observed to occur at pH 8.0. The adsorption data correlated with Freundlich, Langmuir, Dubinin–Radushkevich (D–R), and Temkin isotherms. The Freundlich isotherm showed the best fit to the equilibrium data. The Pseudo-first order and pseudo-second-order kinetic models were studied to analyze the kinetic data. A second-order kinetic model fit the data with the (k2 = 2.8126 × 10?3 g mg?1min?1, 303 K). The intraparticle diffusion models were applied to ascertain the rate-controlling step. The thermodynamic parameters (ΔG°, ΔH°, and ΔS°) were calculated which showed an endothermic adsorption process. The equilibrium parameter (RL) indicated that TiO2 nanocrystals are useful for Hg(II) removal from aqueous solutions. 相似文献
154.
Esfandyari-Manesh M Javanbakht M Dinarvand R Atyabi F 《Journal of materials science. Materials in medicine》2012,23(4):963-972
Water-compatible imprinted nanoparticles were prepared for carbamazepine as a template and used for the selective extraction and controlled release of carbamazepine. Assay materials and drug delivery carriers were typically used in aqueous environments, so it is generally preferable to prepare solvent-free molecularly imprinted nanoparticles in water using the miniemulsion polymerization method. The present work investigates a bio-analytical strategy generically applicable to imprinted materials for molecular recognition studies, including equilibrium and non-equilibrium binding, and release experiments, increasing the knowledge of the molecular interactions between the template molecules and imprinted nanoparticles. The results showed that the imprinted nanoparticles exhibited a higher binding level and slower release rate than non-imprinted nanoparticles. The selectivity of imprinted nanoparticles for carbamazepine studied in comparison with an analogue compound, oxcarbazepine, the main metabolite of carbamazepine. The recovery and selectivity of carbamazepine in human serum was determined to be 100%, 1.7 times that of oxcarbazepine. The results indicated that carbamazepine-imprinted nanoparticles are appropriate for serum level determination of the drug in therapeutic range. The template to functional monomer ratio as a key factor controlling the recognition and release kinetic mechanism of imprinted nanoparticles is discussed. The imprinted nanoparticles prepared at the appropriate template to functional monomer mole ratio (2:8) exhibited the best drug affinity (5.1 times higher) and a slower drug release rate due to the interaction of carbamazepine with the imprinted cavities within the nanoparticles. Loaded imprinted nanoparticles as drug reservoirs were able to prolong carbamazepine release, in 1% wt sodium dodecyl sulfate aqueous solution, for more than 8 days. 相似文献
155.
New liquid–liquid equilibrium data for polyethylene glycol(PEG) 3000 + CHO_2K + H_2O systems were measured at 298.15 K and pH values of 7.95, 8.40 and 9.98. It was found that an increase in pH caused the binodal curve to be displaced downward and the two-phase region to expand. Accordingly, the binodal curve was adjusted to the Pirdashti equation and the tie-line compositions were correlated using the Othmer–Tobias, Bancroft and Hand equations. The study measured the refractive index and densities of several homogeneous binary and ternary solutions. The solutions were used for calibration within a range of 0% to 30% of the mass of the PEG and potassium formate. The density and refractive index data show a linear variation with the mass fraction of the polymer and the salt. The effect of pH on the binodal, tie-line lengths(TLL) and slope of the tie-line(STL) in the systems was examined. It was found that an increase in pH increased the TLL and decreased the STL. It was observed that the density of the aqueous two-phase system was influenced by the TLL. The difference in density between phases(Δρ) increased as the TLL and pH increased. It was found that the TLL and Δρ showed a linear relationship. The effective excluded volume(EEV) of the PEG was obtained and it was found that EEV also increased as the pH increased. 相似文献
156.
Fatemeh Khaleghi Mohammad Tajally Esmaeil Emadoddin Maryam Mohri 《Metals and Materials International》2017,23(5):915-922
Diffusion annealing of palladium-coated Ti-Ni plates was performed at temperatures ranging from 900 °C to 1,000 °C, to accomplish a compositional gradient in Ti-rich, Ti-Ni shape memory alloys. The aim of this study was to increase the transformation temperatures and transformation temperature intervals. Palladium diffusion profiles were measured by energy dispersive spectroscopy, and the corresponding approximate diffusion coefficients of the annealed specimens were calculated. The Gaussian solution of Fick’s second law for the one-dimensional lattice diffusion of a tracer was used. The transformation behavior studies were performed by differential scanning calorimetry. It was depicted that annealed specimens show longer transformation intervals compared to the bare alloy. In addition, annealed specimens showed improved shape memory properties that were attributed to the lower amount of Ti2Ni precipitates in the diffusion layer. The shape memory behaviour of the samples was detected using micro-indentation at room temperature, followed by heating them above the austenite formation temperature to calculate the shape recovery ratio. 相似文献
157.
158.
Encapsulation of Zataria multiflora Bioss. Essential Oil into Nanoliposomes and in Vitro Antibacterial Activity Against Escherichia coli O157:H7
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159.
Anti‐hyperglycemic and anti‐hyperlipidemic effects of Vaccinium myrtillus fruit in experimentally induced diabetes (antidiabetic effect of Vaccinium myrtillus fruit)
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160.
Fatemeh Pariafsai 《建筑学研究前沿(英文版)》2016,5(2):171
In the past few decades, the use of glass in buildings has remarkably increased. As a result, several transparent buildings have been constructed, in which the materials have almost disappeared. Given that the advancement of architecture is inextricably linked to the acquisition of general knowledge on future developments, this study was conducted to predict the paths of development that glass structures are likely to take in the future. Investigations such as this increase the possibility of advancing both design and construction at the same speed as technology. To achieve this goal, this study evaluates the present situation by investigating new possibilities and assessing their effect on the development of glass buildings. The findings of this study show that the durability, safety, appearance, and efficiency of transparent buildings can be improved through continuous refinement of designs, replacement of aged elements, prompt repair of damaged protective coatings, and greater exploitation of double-sided screens. 相似文献