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61.
In the present study, two three-layer feed-forward artificial neural networks (ANNs) and multiple linear regression (MLR) models were developed for modeling the effects of material and process parameters on the powder particle size characteristics generated during high-energy ball milling of Al and B4C powders. The investigated process parameters included aluminum particle size, B4C size and its content as well as milling time. The median particle size (D50) and the extent of size distribution (D90–D10) were considered as target values for modeling. The developed ANN and MLR models could reasonably predict the experimentally determined characteristics of powders during mechanical milling.
相似文献62.
Mohammad B. Ghasemian Mohannad Mayyas Shuhada A. Idrus‐Saidi Muhammad A. Jamal Jiong Yang Sajjad S. Mofarah Esmaeil Adabifiroozjaei Jianbo Tang Nitu Syed Anthony P. O'Mullane Torben Daeneke Kourosh Kalantar‐Zadeh 《Advanced functional materials》2019,29(36)
Liquid metals offer unprecedented chemistry. Here it is shown that they can facilitate self‐limiting oxidation processes on their surfaces, which enables the growth of metal oxides that are atomically thin. This claim is exemplified by creating atomically thin hydrated MnO2 using a Galvanic replacement reaction between permanganate ions and a liquid gallium–indium alloy (EGaIn). The “liquid solution”–“liquid metal” process leads to the reduction of the permanganate ions, resulting in the formation of the oxide monolayer at the interface. It is presented that under mechanical agitation liquid metal droplets are established, and simultaneously, hydrated gallium oxides and manganese oxide sheets delaminate themselves from the interfacial boundaries. The produced nanosheets encapsulate a metallic core, which is found to consist of solid indium only, with the full migration of gallium out of the droplets. This process produces core/shell structures, where the shells are made of stacked atomically thin nanosheets. The obtained core/shell structures are found to be an efficient photocatalyst for the degradation of an organic dye under simulated solar irradiation. This study presents a new research direction toward the modification and functionalization of liquid metals through spontaneous interfacial redox reactions, which has implications for many applications beyond photocatalysis. 相似文献
63.
Asghar Charmin Esmaeil Najafi Aghdam 《Analog Integrated Circuits and Signal Processing》2017,90(2):321-331
In this research a novel low power multi-mode continuous time Delta Sigma modulator was designed to be compatible with many mobile wireless standards. This modulator has a reconfigurable structure to adapt to various standards from 0.2 to 20 MHz. The designed modulator uses a VCO-based quantizer not only for lowering power consumption, but also for reducing the required chip area. The presented modulator can function with up to third order of noise shaping, or in a low power mode in which the loop filter is disabled and only the VCO-based quantizer is used. The proposed modulator was implemented and simulated in transistor level in 180 nm technology. This modulator can digitize at least seven standards (LTE (20 MHz)/WLAN/LTE (9 MHz)/WCDMA/UMTS/Bluetooth/GSM) with a favorable dynamic range (65–89 dB) and power consumption (9.1 mW–670 μW). 相似文献
64.
Esmaeil Heydari Justin R. Sperling Steven L. Neale Alasdair W. Clark 《Advanced functional materials》2017,27(35)
Plasmonic color filtering has provided a range of new techniques for “printing” images at resolutions beyond the diffraction‐limit, significantly improving upon what can be achieved using traditional, dye‐based filtering methods. Here, a new approach to high‐density data encoding is demonstrated using full color, dual‐state plasmonic nanopixels, doubling the amount of information that can be stored in a unit‐area. This technique is used to encode two data sets into a single set of pixels for the first time, generating vivid, near‐full sRGB (standard Red Green Blue color space)color images and codes with polarization‐switchable information states. Using a standard optical microscope, the smallest “unit” that can be read relates to 2 × 2 nanopixels (370 nm × 370 nm). As a result, dual‐state nanopixels may prove significant for long‐term, high‐resolution optical image encoding, and counterfeit‐prevention measures. 相似文献
65.
Esmaeil Biazar 《国际聚合物材料杂志》2017,66(1):28-37
Nanotechnology has potential applications in different sciences, especially in the biological sciences and medicine. The nanomaterials are applicable materials with different morphologies such as nanoparticles, nanotubes, nanowires, nanorods, and nanofibers. The development of nanofibers has greatly enhanced the scope for fabricating designs that can be potentially used in medical sciences. In part III the author summarizes the currently available applications of nanofibers in musculoskeletal and urologic tissues. The graphical abstract shows computed tomography analysis and macroscopic images of calvarial defects in rat, with the regeneration result, after four weeks, of bone healing upon implantation of scaffolds in the defect. (A and D) Control group; (B and E) poly (3-hydroxybutyrate-co-3-hydroxyvalerate)/nanohydroxyapatite (PHBV/nHAp) scaffold; and (C and F) PHBV/nHAp scaffold with unrestricted somatic stem cells precultured in vitro. 相似文献
66.
Evaluation of dynamic viscosity and rheological properties of ceramic materials during liquid phase sintering by numerical‐experimental procedure 下载免费PDF全文
Hamed Yaghoubi Nasrabadi Esmaeil Salahi Fateme Taati Asil 《International Journal of Applied Ceramic Technology》2017,14(6):1222-1235
The effective shear and bulk viscosity, as well as dynamic viscosity, describe the rheological properties of the ceramic body during the liquid phase sintering process. The rheological parameters depend on the physical and thermo‐mechanical characteristics of the material such as relative density, temperature, grain size, diffusion coefficient, and activation energy. In this paper, the numerical‐experimental method has been developed to study both viscous and rheological behavior of hard porcelain ceramic body during liquid phase sintering. The other aim is to acquire a complete understanding of the response of an incompressible viscose material during sintering such as stress‐strain relations, sintering, and hydrostatic stress. Densification results confirmed that the bulk viscosity was well‐defined with relative density. The stress analysis proved that the sintering stress is more than the hydrostatic stress during the entire sintering time so, the sintering process occurs completely. Deflection results showed that the shear viscosity was a fair estimation of real ones. Dilatometry, SEM, XRD investigations as well as bulk viscosity simulation results confirmed that the “mullitisation plateau” was presented as a very little extraordinary expansion at the final sintering stage. 相似文献
67.
Mohammad Zarbayani Esmaeil Jorjani Mirsaleh Mirmohammadi Mohammad Taghi Shadloo Mohammad Noaparast 《北京科技大学学报(英文版)》2010,17(3):251-256
Jajarm's bauxite deposits are mainly diasporic,and they have a low mass ratio of Al2O3/SiO2. It is necessary to increase the run-of-mine mass ratio before feeding the material to the Bayer process. Chemical analysis indicated that the low-grade bauxite sample from Jajarm contained 43.9wt% Al2O3 and 13.35wt% SiO2, resulting in a mass ratio of 3.29. According to mineralogical studies, the presence of aluminosilicate minerals such as kaolinite, illite, and quartz was the main reason for the decrease of the mas... 相似文献
68.
Composite‐supported Pt catalyst and electrosprayed cathode catalyst layer for polymer electrolyte membrane fuel cell 下载免费PDF全文
A major limitation of the conventional polymer electrolyte membrane fuel cell (PEMFC) catalysts is the fast oxidative degradation of their carbon black supports. Complete replacement of carbon black is difficult because of its low‐cost and high electrical conductivity. Reported here are the development and optimization of composite‐supported Pt catalysts and the electrosprayed cathode catalyst layer with these catalysts for PEMFC. These catalysts are supported by a composite of carbon black (Vulcan XC‐72R) and the electrochemically much more stable carbon‐embedded niobium‐doped titanium dioxide nanofibers (C/Nb0.1Ti0.9O2). Four different catalyst supports with 20 wt.% Pt were prepared by air spraying and electrospraying to compare their activity and stability. Vulcan XC‐72R and C/Nb0.1Ti0.9O2 were tested as pristine support materials for comparison as well as 1:3 and 3:1 mixtures by weight of the two pristine support materials (composite supports). The amount of Nafion in the catalyst ink was optimized for each catalyst layer by a volumetric method. An increase in carbon black content of the support layer from 0% to 100% increases the performance of these catalysts in H2/air PEMFCs but also increases the loss of oxygen reduction reaction mass activity. The best balance between PEMFC performance and durability was obtained for the Pt catalyst with 25% carbon black in the support layer, while the highest initial oxygen reduction reaction mass activity was obtained for the catalyst with 75% carbon black content. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
69.
Ebrahim Karimi Saeidabadi Touradj Ebadzadeh Esmaeil Salahi 《Ceramics International》2018,44(17):21053-21066
In the present study, the in-situ synthesized mullite has been prepared successfully by mixing kaolinite with alumina and aluminum nitrate nonahydrate (ANN) powders through high energy milling followed by spark plasma sintering (SPS). Using a high-energy ball-mill, the stoichiometric compositions of the starting powders, considering their final transformation to Al2O3 and SiO2, have been mixed. The SPS process has been performed at 1400 and 1375?°C for the specimens containing Al2O3 and ANN, respectively. XRD patterns of the milled powders after 30?h showed the formation of quartz from kaolinite for both starting batches. The displacement-temperature-time (DTT) curves and the corresponded vacuum changes indicated the dehydration and phase transformation of ANN and kaolinite at different stages of the sintering process. The XRD patterns of the sintered samples revealed the formation of mullite alongside un-reacted Al2O3 and crystobalite for the batches containing Al2O3 and ANN, respectively. The results of the physical and mechanical properties tests showed higher amounts of bending strength (397?±?18?MPa), Vickers hardness (16.32?±?0.21?GPa) and fracture toughness (3.81?±?0.24?MPa?m?1/2) alongside a lower porosity (0.070?±?0.02%) for the prepared sample containing Al2O3, than those of the sample containing ANN. 相似文献
70.
The coal processing methods used at the Zarand coal washery plant are the heavy medium bath,jigs,and flotation.The coal-containing materials that are fed to the plant are acquired from different mines,... 相似文献