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31.
Magnetic induction applications mostly rely on resonance for inducing maximum magnetic fields to system loads and hence for each resonant frequency dedicated circuits are required. Unfortunately, the frequency responses of such inductive systems manifest several peaks (frequency splitting) when their coupling coefficients are equal to or larger than critical coupling. Such frequency responses with several peaks are detrimental when the objective is to transfer maximum energy. Frequency splitting between inductive coils have been seen to date as detrimental to wireless power transfer and inductive communication systems. In this paper it is demonstrated that frequency splitting is a welcome phenomenon with advantage in the design of inductive filter banks and multi-frequency inductive systems. The centre frequencies of the filter banks result from split bands of inductive systems. This phenomenon is applied in conjunction with an innovative recursive algorithm to design inductive filter banks. The filters straddle both sides of the resonant frequency position and can be resolved individually. 相似文献
32.
Shah Dawood Shah Tariq Jamal Sajjad Shaukat 《Multidimensional Systems and Signal Processing》2020,31(3):885-905
Multidimensional Systems and Signal Processing - Algebraic structures and their hardware–software implementation gain considerable attention in the field of information security and coding... 相似文献
33.
Porous aluminium composites are structural and functional materials that have vast potential, due to their lightweight and high energy absorption capacity, especially in automotive and aerospace applications. In this study, the effect of varying content of uncoated and titanium coated diamond particles on the compressive properties of porous aluminium composite was investigated. The composites were developed using powder metallurgy technique and porosity was attained by using polymethylmethacrylate (30 wt.%) as space holder material. The morphology of the pores was found to replicate the shape and size of polymethylmethacrylate particles, that were uniformly distributed in the composites. X-ray diffraction analysis confirmed formation of aluminium carbide in uncoated diamond-based aluminium composites while negligible amount was present in titanium coated porous composites during sintering. The porosities of composites decreased with an increase in diamond content due to the incomplete decomposition of polymethylmethacrylate particles. Moreover, the maximum plateau stress and energy absorption capacity of 9.96 MPa and 1.7 Mj/m3 were obtained for the composites with 8 wt.% of titanium coated diamond particles. Thus, coating inhibits the formation of undesirable compounds and contributes to better interfacial bonding between matrix and reinforcement. 相似文献
34.
Thermally exfoliated graphene oxide reinforced fluorinated pentablock poly(l‐lactide‐co‐ε‐caprolactone) electrospun scaffolds: Insight into antimicrobial activity and biodegradation 下载免费PDF全文
Burcu Saner Okan Azucena Marset Jamal Seyyed Monfared Zanjani Pınar Akkus Sut Ozlem Sen Mustafa Çulha Yusuf Menceloglu 《应用聚合物科学杂志》2016,133(22)
Three‐dimensional fluorinated pentablock poly(l ‐lactide‐co‐ε‐caprolactone)‐based scaffolds were successfully produced by the incorporation of thermally exfoliated graphene oxide (TEGO) as an antimicrobial agent with an electrospinning technique. In a ring‐opening polymerization, the fluorinated groups in the middle of polymer backbone were attached with a perfluorinated reactive stabilizer having oxygen‐carrying ability. The fiber diameter and its morphologies were optimized through changes in TEGO amount, voltage, polymer concentration, and solvent type to obtain an ideal scaffold structure. Instead of the widely used graphene oxide synthesized by Hummer's method, TEGO sheets having a low amount of oxygen produced by thermal expansion were integrated into the fiber structure to investigate the effect of the oxygen functional groups of TEGO sheets on the degradation and antimicrobial activity of the scaffolds. There was no antimicrobial activity in TEGO‐reinforced scaffolds in the in vitro tests in contrast to the literature. This study confirmed that a low number of oxygen functional groups on the surface of TEGO restricted the antimicrobial activity of the fabricated composite scaffolds. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43490. 相似文献
35.
Shabnam Sanaei Navid Mostoufi Ramin Radmanesh Rahmat Sotudeh‐Gharebagh Christophe Guy Jamal Chaouki 《加拿大化工杂志》2010,88(1):1-11
Effect of temperature on the hydrodynamics of bubbling gas–solid fluidized beds was investigated in this work. Experiments were carried out at different temperatures ranged of 25–600°C and different superficial gas velocities in the range of 0.17–0.78 m/s with sand particles. The time‐position trajectory of particles was obtained by the radioactive particle tracking technique at elevated temperature. These data were used for determination of some hydrodynamic parameters (mean velocity of upward and downward‐moving particles, jump frequency, cycle frequency, and axial/radial diffusivities) which are representative to solids mixing through the bed. It was shown that solids mixing and diffusivity of particles increases by increasing temperature up to around 300°C. However, these parameters decrease by further increasing the temperature to higher than 300°C. This could be attributed to the properties of bubble and emulsion phases. Results of this study indicated that the bubbles grow up to a maximum diameter by increasing the temperature up to 300°C, after which the bubbles become smaller. The results showed that due to the wall effect, there is no significant change in the mean velocity of downward‐moving clusters. In order to explain these trends, surface tension of emulsion between the rising bubble and the emulsion phase was introduced and evaluated in the bubbling fluidized bed. The results showed that surface tension between bubble and emulsion is increased by increasing temperature up to 300°C, however, after that it acts in oppositely. 相似文献
36.
Qin Zhao Ruxangul Jamal Li Zhang Minchao Wang Tursun Abdiryim 《Nanoscale research letters》2014,9(1):557
In this study, a simple one-step template-free solution method was developed for the preparation of poly(3,4-ethylenedioxythiophene) (PEDOTs) with different morphologies by adjusting various ratios of oxidant (FeCl3·6H2O) to monomer (3,4-ethylenedioxythiophene (EDOT)). The results from structural analysis showed that the structure of PEDOT was strongly affected by the oxidant/monomer ratio, and the polymerization degree, conjugation length, doping level, and crystallinity of PEDOT decreased with increasing of the oxidant/monomer ratio. The morphological analysis showed that PEDOT prepared from an oxidant/monomer ratio of 3:1 displayed a special coral-like morphology, and the branches of ‘coral’ would adjoin or grow together with increasing content of oxidant in the reaction medium; consequently, the morphology of PEDOT changed from coral to sheets (at an oxidant/monomer ratio of 9:1). The electrochemical analysis proved that the PEDOT prepared from an oxidant/monomer ratio of 3:1 had the lowest resistance and the highest specific capacitances (174 F/g) at a current density of 1 A/g with a capacity retention rate of 74% over 1,500 cycles, which indicated that the PEDOT with a coral-like morphology could be applied as a promising electrode material for supercapacitors. 相似文献
37.
38.
Electrochemical investigations of pitting corrosion behaviour of type UNS S31603 stainless steel in thiosulfate-chloride environment 总被引:1,自引:0,他引:1
The pitting corrosion behaviour of type UNS S31603 stainless steel (316L SS) in 0.01, 0.05 and 0.1 M thiosulfate ion (S2O3
2–) in the absence and presence of various concentrations of chloride ion (Cl–) was studied using the cyclic potentiodynamic polarization method. The influence of major factors which affect pitting corrosion such as pH and temperature, were also investigated. It was found that both the pitting potential (E
pit) and the repassivation potential (E
rp) decreased with increase in Cl– concentration and solution temperature and a more pronounced difference in E
pit values for various concentrations of S2O3
2– in 1.0 M Cl– was obtained at lower temperatures. The effect of pH on E
pit, E
corr and E
rp values for different concentrations of S2O3
2– in the presence of 1.0 M Cl– was also determined. 相似文献
39.
Cameron Derry Yiliang Wu Shiping Zhu Jamal Deen 《Journal of Electronic Materials》2013,42(12):3481-3488
A nonpercolating network of non-covalently functionalized single-walled carbon nanotubes was embedded within air-stable poly[5,5′-bis(3-dodecyl-2-thienyl)-2,2′-bithiophene] (PQT-12) thin films for the purpose of enhancing the field-effect mobility in thin-film transistors. The host polymer was used to stabilize the nanotubes in suspension through π-orbital overlap caused by simple application of ultrasonication. The stable nanotube suspension was cast into two different device architectures, both of which exhibited excellent on/off ratios ranging from 105 to 106 and dramatically improved mobilities compared with pristine PQT-12 semiconductor. A single-layer film with nanotubes embedded throughout was easy to fabricate and had mobility up to 0.34 cm2/Vs, an enhancement of over 3× compared with PQT-12. Placing the nanotubes closer to the dielectric surface in a dual-layer approach resulted in a mobility improvement of up to six times (0.58 cm2/Vs). The effects of the nanotube content on the polymer interaction within the suspension, film morphology, and electrical properties were investigated as well. 相似文献
40.