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101.
Reza Ojani Jahan-Bakhsh RaoofYusef Ahmady-Khanghah Saeid Safshekan 《International Journal of Hydrogen Energy》2013
The present work describes the electrocatalytic oxidation of formaldehyde on a copper-polymer modified electrode. The deposition of polymeric film on the surface of carbon paste electrode (CPE) was carried out using consecutive cyclic voltammetry in an aqueous solution of 2-aminodiphenylamine (2ADPA). The transition metal of copper is incorporated into the polymer by electrodeposition of Cu(??) from CuCl2 acidic solution using potentiostatic technique. Characterization of different modified electrodes was studied using SEM technique and electron probe microanalyzer (EPMA). Cyclic voltammetry experiment of copper-poly(2-aminodiphenylamine) modified carbon paste electrode (Cu/P(2ADPA)/MCPE) in alkaline solution exhibited a number of well-defined anodic and cathodic peaks that are attributed to the Cu/Cu(I), Cu/Cu(II), Cu(I)/Cu(II) and Cu(II)/Cu(III) redox couples. The electrocatalytic oxidation of formaldehyde at the surface of Cu/P(2ADPA)/MCPE was studied by cyclic voltammetry and chronoamperometry methods. This new modified electrode found to be highly active and stable for electrooxidation of the formaldehyde so that the electrocatalytic current density of 25.56 mA cm−2 was obtained at the potential of 0.63 V. The effects of various parameters such as the copper loading, scan rate and formaldehyde concentration on the electrocatalytic oxidation of formaldehyde were also investigated. Finally, using a chronoamperometric method, the catalytic rate constant (k) for oxidation of formaldehyde was found to be 7.16 × 106 cm3 mol−1 s−1. 相似文献
102.
Saeid Shahraki Sami Khorasani Reza Abdi Behnagh Yassin Fotouhi Hosein Bisadi 《Metallurgical and Materials Transactions B》2013,44(6):1546-1553
In this study, friction stir processing (FSP) was used to produce AA5083/ZrO2 nanocomposite layer. Optical microscopy and SEM were used to probe the microstructures formed in the composite layer. In addition, the mechanical properties of each sample are characterized using both tensile and hardness tests. Results showed that FSP is an effective process to fabricate AA5083/ZrO2 nanocomposite layer with uniform distribution of ZrO2 particles, good interfacial integrity, and significant grain refinement. On processing, in the proper combination of process parameters, the metal matrix composite layer was observed to have increased tensile and hardness properties. 相似文献
103.
Cold rolled coils are subjected to the annealing process in order to improve their formability and mechanical properties. A mathematical model of thermal behavior of coils during the heating cycle has been developed. Based on experimental data from several tests, the accuracy of the model has been confirmed. This model enables us to determine the coldest point of coils and the end time of furnace operation. Furthermore, the model has been used to analyze the effect of strip thickness on the heating time required. Thinner strips lead to prolonged heating time and larger temperature differences within the coil. 相似文献
104.
105.
Saeid Rahimi-Razin Mehdi Salami-Kalajahi Vahid Haddadi-Asl Hossein Roghani-Mamaqani 《Journal of Polymer Research》2012,19(9):1-16
Polymer-clay nanocomposites have been prepared by free radical and RAFT polymerizations. To investigate the effects of nanoclay content and its modification system on the kinetics of polymerization, two different commercial grades of clay including Na-MMT and Cloisite 30B have been used and a method has been developed for further modification of Na-MMT with two commercial modifiers containing either a long organic chain or a vinyl group. Also, kinetics of free radical and RAFT polymerizations of both styrene and methyl methacrylate in the presence of these nanoclays was studied. Morphology of the nanocomposites has been studied by XRD and the results have been assessed with TEM observations. Exfoliated structure was obtained for the nanocomposites with 1?wt.% of vinyl-containing clays. Thermogravimetric behavior of the nanocomposites has been studied by TGA. Incorporation of clays has resulted in an evident increase in thermal stability of both polymers. 相似文献
106.
Principles and Applications of Light Backscattering Imaging in Quality Evaluation of Agro-food Products: a Review 总被引:1,自引:0,他引:1
Kaveh Mollazade Mahmoud Omid Fardin Akhlaghian Tab Sayed Saeid Mohtasebi 《Food and Bioprocess Technology》2012,5(5):1465-1485
In recent years, due to the increasing consciousness of quality in the food and health sector, much progress has been made
in developing non-invasive techniques for the evaluation or inspection of internal qualitative parameters of fruits, vegetables,
and processed foodstuffs considering, e.g., moisture content, soluble solid content, acidity, and mechanical properties. This
paper reviews the theoretical and technical principles as well as the recent achievements and applications of light backscattering
imaging for nondestructive evaluation of food and agricultural produce. The results suggest the potential use of this emerging
technique in the food industry. Further attempts are pointed out to improve its performance through utilizing advanced image
processing coupled with artificial intelligence techniques. 相似文献
107.
Sparsity has been shown to be very useful in source separation of multichannel observations. However, in most cases, the sources of interest are not sparse in their current domain and one needs to sparsify them using a known transform or dictionary. If such a priori about the underlying sparse domain of the sources is not available, then the current algorithms will fail to successfully recover the sources. In this paper, we address this problem and attempt to give a solution via fusing the dictionary learning into the source separation. We first define a cost function based on this idea and propose an extension of the denoising method in the work of Elad and Aharon to minimize it. Due to impracticality of such direct extension, we then propose a feasible approach. In the proposed hierarchical method, a local dictionary is adaptively learned for each source along with separation. This process improves the quality of source separation even in noisy situations. In another part of this paper, we explore the possibility of adding global priors to the proposed method. The results of our experiments are promising and confirm the strength of the proposed approach. 相似文献
108.
Sara Safaeian Laein Saeid Khanzadi Mohammad Hashemi Fatemeh Gheybi Mohammad Azizzadeh 《Journal of food science》2022,87(7):2920-2931
The present study was conducted to determine the characterization and antibacterial activity of peppermint essential oil-loaded solid lipid nanoparticle (PEO–SLN) and its impact on the quality of trout fillet stored at 4 ± 1°C for 12 days. The SLNs were prepared through a bath sonication technique. PEO–SLNs contained 0.2% (w/v) PEO in 2% of lipid phase glycerol monostearate (GMS) and tween 80 (1% w/v) used as a surfactant in the aqueous phase. The characterization parameter of PEO–SLN was evaluated, and the antibacterial activity of PEO–SLNs was conducted under in vitro conditions. Trout samples were analyzed for inoculated Pseudomonas aeruginosa, Listeria monocytogenes, and Escherichia coli O157:H7 during refrigerated storage. The mean particle size of PEO–SLNs was 154.83 ± 1.21 nm with a polydispersity index (PDI) of 0.35 ± 0.01 and zeta potential was about −24.16 ± 0.51 mV. The results indicated that PEO–SLN had higher antibacterial activity than the free form of PEO and also when used in combination with gelatin coating (gel + PEO–SLN) had a significant effect on preventing microbial growth in trout fillets (p < 0.05). The most decreasing rate of P. aeruginosa (1.92 log CFU/g), E. coli O157:H7 (0.71 log CFU/g), and L. monocytogenes count (1.69 log CFU/g) was seen in gel + PEO–SLN. These findings illustrated that PEO–SLNs could potentially be utilized in the food industry to increase the shelf life of fish fillets. 相似文献
109.
Mohammad Bemani Saeid Nikmehr Shahram Hosseinzadeh 《AEUE-International Journal of Electronics and Communications》2013,67(5):382-386
This paper focused on the application of negative refractive index transmission line (NRI-TL) in dual-band unequal Wilkinson power divider (WPD) with controllable frequency and power dividing ratio. Theory and design procedure of the dual-band NRI-TL are presented in details. For demonstration, two dual-band unequal Wilkinson power dividers (WPDs) with power dividing ratio of 2 : 1 and operating frequencies of 0.9 and 1.8 GHz are designed, fabricated and tested. The first unequal divider is based on 2-stage NRI-TLs and the second one is based on 4-stage NRI-TLs. In addition, these two types of NRI-TLs are presented to demonstrate that by increasing the number of NRI-TL unit-cells the phase response of the NRI-TLs converge to the desired characteristic. The good agreement between measured and simulated results confirmed the design concept and derived closed-form design equations. Measurements show that the first divider has 18.37% and 21.86% relative bandwidths and the second one has 33.52% and 29.12% relative bandwidths at 0.9 and 1.8 GHz, respectively. The design concept of this paper can be extended to equal dual-band power dividers with arbitrary frequency ratio. 相似文献
110.
Mahmoud Omid Mahmoud SoltaniMohammad Hadi Dehrouyeh Seyed Saeid MohtasebiHojat Ahmadi 《Journal of food engineering》2013
The main purpose of this research was design and development of an intelligent system based on combined fuzzy logic and machine vision techniques for grading of egg using parameters such as defects and size of eggs. The detected defects were internal blood spots, cracks and breakages of eggshell. The Hue-Saturation-Value (HSV) color space was found useful in obtaining visual features during Image Processing (IP) stage. The fuzzy inference system (FIS) was designed based on triangular and trapezoidal membership functions, fuzzy rules with logical operator of AND inference system of Mamdani and method of center average for defuzzifier. The evaluation results of IP algorithms showed that use of IP technique has good performance for defects and size detection. The Correct Classification rate (CCR) was 95% for size detection, 94.5% for crack detection and 98% for breakage detection. The overall accuracy FIS model in grading of the eggs was 95.4. 相似文献