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991.
A Combined Analytic,Numeric, and Experimental Investigation Performed on NiTi/NiTiCu Bi‐Layer Composites under Tensile Loading 下载免费PDF全文
Milad Taghizadeh Mahmoud Nili‐Ahmadabadi Mostafa Baghani Mohammad Hassan Malekoshoaraei 《Advanced Engineering Materials》2018,20(2)
992.
Eric R. Meshot Keval D. Patel Sameh Tawfick K. Anne Juggernauth Mostafa Bedewy Eric A. Verploegen Michaël F. L. De Volder A. John Hart 《Advanced functional materials》2012,22(3):577-584
Hybrid nanostructured materials can exhibit different properties than their constituent components, and can enable decoupled engineering of energy conversion and transport functions. Novel means of building hybrid assemblies of crystalline C60 and carbon nanotubes (CNTs) are presented, wherein aligned CNT films direct the crystallization and orientation of C60 rods from solution. In these hybrid films, the C60 rods are oriented parallel to the direction of the CNTs throughout the thickness of the film. High‐resolution imaging shows that the crystals incorporate CNTs during growth, yet grazing‐incidence X‐ray diffraction (GIXD) shows that the crystal structure of the C60 rods is not perturbed by the CNTs. Growth kinetics of the C60 rods are enhanced 8‐fold on CNTs compared to bare Si, emphasizing the importance of the aligned, porous morphology of the CNT films as well as the selective surface interactions between C60 and CNTs. Finally, it is shown how hybrid C60–CNT films can be integrated electrically and employed as UV detectors with a high photoconductive gain and a responsivity of 105 A W?1 at low biases (± 0.5 V). The finding that CNTs can induce rapid, directional crystallization of molecules from solution may have broader implications to the science and applications of crystal growth, such as for inorganic nanocrystals, proteins, and synthetic polymers. 相似文献
993.
Bayat Majid Barmshoory Mostafa Rahimi Majid Aref Mohammd Reza 《Wireless Networks》2015,21(5):1733-1743
Wireless Networks - Vehicular Ad-hoc Networks (VANETs) will start becoming deployed within the next decade. Among other benefits, it is expected that VANETs will support applications and services... 相似文献
994.
Mostafa Danaeian Esmail Zarezadeh Hossein Ghayoumi-Zadeh 《Analog Integrated Circuits and Signal Processing》2018,94(3):469-479
In this paper, a novel compact microstrip dual-band (DB) bandpass filter with high selectivity for wireless local area networks applications is proposed. The design procedure is based on unbalanced composite right/left-handed (UCRLH) transmission lines (TLs). The DB features can be achieved by unbalancing the CRLH transmission line. The necessary conditions to obtain a discontinuous transition between the left- and right-handed bands, intended to provide UCRLLH TL, are investigated. The application of this technique to design of compact DB filters is illustrated. The structure of the proposed DB filter is implemented by a series interdigital capacitor located between two microstrip lines that shorted to the ground plane by vias. The vias with microstrip lines acting as a shunt connected inductor while the series capacitor is realized by interdigital capacitor. The design procedure based on a simple equivalent circuit is also introduced. The proposed filter has advantages such as compact size, easy fabrication, high selectivity, low insertion loss, high return loss and, design flexibility. To validate the proposed technique, the proposed DB filter has been fabricated and tested. Good agreement has been found between simulation and measurement results. The total size of the proposed UCRLH DB filter is 0.17 λg × 0.048 λg, where λg is the guided wavelength of the lower pass-band. The size of the proposed DB filter is more compact in comparison with known similar filters. 相似文献
995.
Iftikhar Hussain Sumanta Sahoo Tanveer Hussain Muhammad Ahmad Muhammad Sufyan Javed Charmaine Lamiel Shuai Gu Thanayut Kaewmaraya Mostafa Saad Sayed Kaili Zhang 《Advanced functional materials》2023,33(7):2210002
Recently metal-organic framework (MOF) derived electrode materials have grown considerable research interest in the field of supercapacitor (SC) technology. Herein, MOF-derived Zr-Mn-oxide is successively combined with solution-free CuO nanowires not only to avoid the structural limitations of MOF but also to fabricate a positive-negative hybrid electrode material. The MOF-derived mixed metal oxide prepared through in situ fabrication allows the uniform and unidirectional growth of oriented Zr-Mn-oxide@CuO@Cu. The hybrid electrode exhibited over 100% stability after 20,000 cycles in a three-electrode setup with a wide potential window range of 1.2 V (−0.6 to 0.6 V). Further, the obtained Zr-Mn-oxide@CuO@Cu hybrid electrode exhibited 14.1- and 5.5-fold higher capacity over its MOF-derived Zr-Mn-oxide counterpart (−0.6 to 0.1 V) and CuO (0.0 to 0.5 V), respectively. Additionally, the hybrid device with hybrid Zr-Mn-oxide@CuO@Cu as the positive electrode and reduced graphene oxide as the negative electrode also displayed promising energy and power densities. Furthermore, density functional theory calculations are employed to study the hybrid electrode material's properties. Overall, the unidirectional and vertically aligned MOF-derived Zr-Mn-oxide@CuO@Cu hybrid electrode material with notable electrochemical performance can be useful for the fabrication of next-generation supercapacitor electrodes. 相似文献
996.
Mostafa I. Abd-Elrahman Mahrous O. Ahmed Jelan A. Abdel-Aleem 《Materials Science in Semiconductor Processing》2013,16(3):1052-1056
Polymeric films composed of mixture of ethyl cellulose (EC) and hydroxypropyl cellulose (HPC) are prepared from casting combined solvent (methylene chloride and methanol in 1:1 ratio) containing 8% weight/volume of both polymers (EC to HPC in 1:3 weight ratio). The structural and optical studies of the films are carried out by X-ray diffraction and UV–vis spectrophotometer. The films are polycrystalline structure with an average grain size from 23.15 to 10.79 nm. The possible optical transition in these films is found to be allowed direct transition. The optical band gap energy (Eg) is estimated to be 5.02 eV for HPC–EC plain film and then decreases with increasing the filler content reaching to 4.24 eV for the film filled with maximum Se80Te14Sn6 content of 1 w%. This suggests that Se80Te14Sn6, as filler, is a good choice to control the optical properties of HPC–EC blend film. 相似文献
997.
The melt-spinning processes of binary Sn–10 wt.% Sb and ternary Sn–10 wt.% Sb–In were analyzed using X-ray diffractometer and differential thermal analysis (DTA). The results showed that supersaturated solid solution and new intermetallic compound In3Sn were produced during melt-spinning technique not found under equilibrium conditions. It is also found that a small amount of In addition significantly lowers the melting point of the Sn–10 wt.% Sb alloy and reduce the crystal size to ≈60 nm. Also, tin–antimony solder doped with In exhibits good mechanical properties, Vickers hardness and mechanical strength due to refined microstructure. This work was performed to study the influence of rapid solidification and indium addition on structure and properties of tin–antimony based alloys. 相似文献
998.
Modification of chitin by grafting with itaconic acid (IA) was carried out using potassium persulfate as redox initiator. In complimentary experiments, grafting was performed using γ‐radiation. Grafting was confirmed by FTIR spectroscopy. The effect of monomer concentration, initiator concentration and copolymerization temperature on the percentage of grafting were studied. The effect of radiation dose was also investigated. Values for percentages of grafting of up to 300 % were reached. It was observed that the percentage of grafting increased with increasing monomer concentration and showed a tendency to level off at IA concentration of 0.1 mol l?1. The percentage of grafting increased with temperature up to 60 °C and then decreased. The solubility of the grafted chitin was studied in organic and inorganic solvents. The complexation of the grafted chitin with some cations, namely copper, nickel, cobalt, zinc and lead, was also investigated. The metal uptake was measured by UV spectroscopy. Thermogravimetric analysis of the grafted chitin was also studied. Copyright © 2004 Society of Chemical Industry 相似文献
999.
Laboratory Evaluation of the Use of Alkaline Phosphate Wastes for the Control of Acidic Mine Drainage 总被引:1,自引:1,他引:0
Pyrrhotite tailings at the abandoned Kettara mine site in Morocco are producing acid mine drainage (AMD). We investigated
the use of alkaline phosphate waste (APW) rock from a nearby operating open-pit phosphate mine to control the AMD. The neutralizing
potential of the APW, using the Paktunc method, was estimated between 500 and 680 kg CaCO3/t. In laboratory column tests, the addition of 15 wt% APW to the coarse Kettara tailings produced leachates with significantly
lower acidities and metal concentrations than unamended controls. The high calcium concentration in the flushed solutions
indicates that calcite was responsible for the neutralization. Dolomite dissolution seems to be negligible and fluorapatite
was stable under the testing conditions. It was also observed that when the treated solution comes in contact with unweathered
Kettara coarse tailings, the pH becomes acidic, although the metal concentrations remain low. 相似文献
1000.
Urmia Lake, located in a closed basin in north-west Iran, is the largest lake (5000–6000 km2) in the Middle East. It is very saline with total dissolved salts reaching 200 g/l compared with a normal seawater salinity of about 35 g/l. The construction of a causeway, which was initiated in 1979 but then abandoned until the early 2000s, is near completion and will provide road access between the western and eastern provinces. The causeway has an opening 1.25 km long and divides Urmia Lake into a northern and southern basin and restricts water exchange. The flow and salinity regimes are affected by the presence of this new causeway, and there are concerns over the well being of the Artemia population. This study investigates the effects of the construction of the causeway on flow and salinity regimes, considers remedial actions, and examines the effects of climatic variability on salinity and flow. Flow and salinity regimes were numerically simulated by using a commercially available two and three-dimensional (2D and 3D) MIKE model. The validity of the numerical model was assessed through sensitivity analysis of the model and comparing the simulated results against field measurements; the 3D model provided the higher correlation between simulated and actual data. Wind input was the main climatic and hydrologic factor influencing flow regime while river discharge, evaporation and rainfall were the key parameters affecting salinity distribution in the lake models. The 3D model was subsequently used to predict lake conditions in typical dry, wet and normal climates, to examine the environmental impacts from the new causeway, and to evaluate possible improvements that some remedial measures may provide. 相似文献