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991.
Said Suhana Mohd Bashir Mohamed Bashir Ali Sabri Mohd Faizul Mohd Miyazaki Yuzuru Shnawah Dhafer Abdul Ameer Hakeem Abbas Saeed Shimada Masanori Bakare Akolade Idris Ghazali Nik Nazri Nik Elsheikh Mohamed Hamid 《Metallurgical and Materials Transactions A》2017,48(6):3073-3081
Metallurgical and Materials Transactions A - In this work, the effects of Te doping on the microstructure and thermoelectric properties of the partially filled skutterudite La0.5Co4Sb12 compounds... 相似文献
992.
Fatemeh Sadat HOSEINIAN Aliakbar ABDOLLAHZADE Saeed Soltani MOHAMADI Mohsen HASHEMZADEH 《中国有色金属学会会刊》2017,27(3):686-693
The artificial neural network (ANN) and hybrid of artificial neural network and genetic algorithm (GANN) were applied to predict the optimized conditions of column leaching of copper oxide ore with relations of input and output data. The leaching experiments were performed in three columns with the heights of 2, 4 and 6 m and in particle size of <25.4 and <50.8 mm. The effects of different operating parameters such as column height, particle size, acid flow rate and leaching time were studied to optimize the conditions to achieve the maximum recovery of copper using column leaching in pilot scale. It was found that the recovery increased with increasing the acid flow rate and leaching time and decreasing particle size and column height. The efficiency of GANN and ANN algorithms was compared with each other. The results showed that GANN is more efficient than ANN in predicting copper recovery. The proposed model can be used to predict the Cu recovery with a reasonable error. 相似文献
993.
994.
Mashallah Rezakazemi Abouzar Azarafza Amir Dashti Saeed Shirazian 《International Journal of Hydrogen Energy》2018,43(36):17283-17294
The present paper aims to use intelligent methods for prediction of gas permeation in binary-filler nanocomposite membranes containing fumed silica (FS) and octatrimethylsiloxy polyhedral oligomeric silsesquioxane (POSS) nanoparticles incorporated within a polymer matrix of polydimethylsiloxane (PDMS). Two reliable and rigorous hybrid models, i.e., differential evolution-adaptive neuro-fuzzy inference system (DE-ANFIS) and coupled simulated annealing-least square support vector machine (CSA-LSSVM) were developed in order to predict pure gas permeability of including H2, CH4, CO2, and C3H8 through the nanocomposite membranes. The coupled simulated annealing (CSA) optimization algorithm was also used for tuning of the model parameters. The impacts of several key parameters such as pressure, FS nanoparticles loading as well as the kinetic diameter of gases on permeation were investigated. The experimental data were randomly divided into two main groups, namely training (70%) and testing (30%) sets. The results of the study suggested that DE-ANFIS model is a more robust and accurate model than the CSA-LSSVM with the R2 values of 0.9981 and 0.9689, respectively. 相似文献
995.
Naila Khalid Ahtaram Bibi Khalida Akhtar Kashif Mustafa Mussabeha Khan Nishat Saeed 《Polymer-Plastics Technology and Engineering》2019,58(4):419-426
A series of bromo-substituted triphenylamine based poly(azomethine)s (P1-P3) were synthesized from the N1-(4-aminophenyl)-N1-(4-bromophenyl)benzene-1,4-diamine (DA) and aromatic dialdehydes. The viscosity of P1-P3 solutions (0.97 to 1.12 g dL?1) and molecular weight distribution analysis by Gel Permeation Chromatography (GPC) discloses the attainment of appreciable molecular weight. The optical transparency and fluorescence properties of the P1-P3 were explored by UV-vis and photoluminescence spectral analysis. From which it was concluded that the presence of 4-bromotriphenylamine and azomethine (CH = N) linkage in our synthesized materials are possibly responsible for the fluorescence with quantum efficiencies of 0.9–2.1 %. 相似文献
996.
A modified Weibull model incorporating the within-fibre diameter variation is applied to examine the fibre diameter effect on the strength of single fibres. Australian Superfine Merino Wool (ASFW) and Inner Mongolia Cashmere (IMC) were used in the present work, since these animal fibres tend to have relatively large diameter variations. To determine single fibre strength, tensile measurements were carried out for fibres with diameters varying between 9 and 21?μm at a constant gauge length. It was found that an increase in the diameter disparity along the fibre reduces the strength of fibres. To validate this, the accuracy of predicting weak-link scaling was evaluated; the results showed that the application of modified Weibull distribution gives a better relationship with the empirical data than the standard Weibull model. The results suggest that the modified Weibull model is more accurate in predicting the size dependence and strength of single fibres with diameter variations. 相似文献
997.
The mixed convection fluid flow in a square cavity filled with AL2O3‐water non‐Newtonian nanofluid is numerically analyzed. The left and right vertical boundaries of the enclosure have been kept in the constant temperature. Remaining walls of the cavity have been considered to have adiabatic boundary condition. Two different cases have been considered. In the first case, left and right side walls have been moved vertically with constant speed Vb in opposite directions. In the second case, the directions of their motions have been reversed. The transport equations, written in terms of the primitive variables for the non‐Newtonian nanofluid, have been solved numerically using the finite volume method. The shear stresses were calculated using the Ostwald‐de Waele model for the shear‐thinning nanofluid. The model introduced by Patel et al was used to obtain the thermal conductivity of the nanofluid. The variation of the fluid flow with respect to the Richardson number and volume fraction of the nanoparticles was investigated through a parametric study. Even though increasing the volume fraction of nanoparticles leads to heat transfer enhancement, for the second case of this study, for Ri = 1, the average Nusselt number initially drops sharply by increasing the volume fraction of nanoparticles, then remains constant. 相似文献
998.
The nitrogen oxide (NOx) release of diesel engines can be reduced using water in diesel emulsion fuel without any engine modification. In the present paper, different formulations of water in diesel emulsion fuels were prepared by ultrasonic irradiation. The water droplet size in the emulsion, polydisperisty index, and the stability of prepared fuel was examined, experimentally. Afterwards, the performance characteristics and exhaust emission of a single cylinder air-cooled diesel engine were investigated using different water in diesel emulsion fuels. The effect of water content (in the range of 5%–10% by volume), surfactant content (in the range of 0.5%–2% by volume), and hydrophilic-lipophilic balance (HLB) (in the range of 5–8) was examined using Box-Behnken design (BBD) as a subset of response surface methodology (RSM). Considering multi-objective optimization, the best formulation for the emulsion fuel was found to be 5% water, 2% surfactant, and HLB of 6.8. A comparison was made between the best emulsion fuel and the neat diesel fuel for engine performance and emission characteristics. A considerable decrease in the nitrogen oxide emission (–18.24%) was observed for the best emulsion fuel compared to neat diesel fuel. 相似文献
999.
1000.
Farah Ahmad Imran Pasha Muhammad Saeed Muhammad Asgher 《International Journal of Food Properties》2018,21(1):1586-1597
Cereals like sorghum and millet are splendid sources of phenolics, dependent on their genetic makeup, and possess varied levels of flavonoids, flavanols, flavanones, anthocyanins, and condensed tannins. In this study, chemical composition and anthocyanin and tannin content of seven sorghum and two millet varieties were evaluated. American Association of Cereal Chemists (AACC) respective methods were used for chemical composition. Anthocyanins were determined through HPLC/UV-Vis, while condensed tannins were determined spectrophotometrically. Four anthocyanins determined included apigeninidin, kuromanin, pelargonidin, and cyanidin. Among sorghum varieties, JS-263 had the highest apigeninidin (16 µg/g). Other anthocyanins were not found in appreciable quantities. None of the anthocyanins were detected in millet varieties. Condensed tannins were highest in sorghum variety PC-1 (179.76 mg/100g) and millet variety S. Bajra-2011 (172.75 mg/100g). Two varieties, one each from sorghum and millet, were selected for extraction of bran as a separate fraction. Brans were modified by size reduction and enzymatic treatment (xylanase and cellulase). Enzymatic treatment favorably affected the extraction of phenolic compounds like anthocyanins. Sorghum and millet flour- and bran-supplemented breads were also developed and evaluated for sensory acceptability. 相似文献