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991.
This paper deals with the problem of magnetothermoelastic interactions in a perfectly conducting elastic medium in which the boundary is stress free and subjected to thermal loading in the context of the fractional-order, two-temperature generalized thermoelasticity theory (2TT). The two-temperature, three-phase-lag (2T3P) model and two-temperature Lord–Shulman (2TLS) model of thermoelasticity are combined into a unified formulation introducing unified parameters. The governing equations of generalized thermoelasticity of these models under the influence of a magnetic field are established. The basic equations have been written in the form of a vector-matrix differential equation in the Laplace-transform domain, which is then solved by the state-space approach. The numerical inversion of the transform is carried out by a method based on Fourier-series expansion techniques. Because of the short duration of the second sound effects, small time approximations of the solutions are studied. The numerical estimates of the quantities of physical interest are obtained and depicted graphically. The effect of the fractional-order parameter and the two-temperature and magnetic field parameters on the solutions has been studied and the comparisons among different thermoelastic models are made. 相似文献
992.
Mishra Dheerendra Vijayakumar P. Sureshkumar Venkatasamy Amin Ruhul Islam SK Hafizul Gope Prosanta 《Multimedia Tools and Applications》2018,77(14):18295-18325
Multimedia Tools and Applications - In current times, multimedia application includes integrated sensors, mobile networks and Internet-of-Things (IoT) services. In IoT services, if more devices are... 相似文献
993.
Lupin is an emerging crop worldwide due to its wide range of health benefits. In this study, a comprehensive proteome analysis was conducted using mature seed of four narrow leafed lupin cultivars, Uniharvest, Yorrel, Tanjil and Coromup, through two-dimensional gel electrophoresis followed by mass spectrometric protein sequencing. Two-dimensional gels recognised about 400 protein spots among the cultivars in the 10-100kDa molecular weight and 5.0-8.5 PI ranges. The results revealed a considerable variation of protein expression patterns with a total of 24 proteins showed differential expression among the cultivars, among which 19 were identified as β-conglutin, and 8 were identified as allergenic proteins. Most of the α, δ and γ-conglutins were showing similar expression among the cultivars. Overall, the differentially expressed proteins especially the cultivar specific proteins would be valuable markers for cultivar identification and for screening parental lines of low allergenicity in breeding process. 相似文献
994.
The paper presents a preview controller design for ATS (active trailer steering) systems to improve high-speed stability of AHVs (articulated heavy vehicles). An AHV consists of a towing unit, namely tractor or truck, and one or more towed units which called trailers. Individual units are connected to one another at articulated joints by mechanical couplings. Due to the multi-unit configurations, AHVs exhibit unique unstable motion modes, including jack-knifing, trailer swing and rollover. These unstable motion modes are the leading cause of highway accidents. To prevent these unstable motion modes, the preview controller, namely the LPDP (lateral position deviation preview) controller, is proposed. For a truck/full-trailer combination, the LPDP controller is designed to control the steering of the front and rear axle wheels of the trailing unit. The calculation of the corrective steering angle of the trailer front axle wheels is based on the preview information of the lateral position deviation of the trajectory of the axle center from that of the truck front axle center. Similarly, the steering angle of the trailer rear axle wheels is calculated by using the lateral position deviation of the trajectory of the axle center from that of the truck front axle. To perform closed-loop dynamic simulations and evaluate the vehicle performance measure, a driver model is introduced and it 'derives' the AHV model based on well-defined testing specifications. The proposed preview control scheme in the continuous time domain is developed by using the LQR (linear quadratic regular) technique. The closed-loop simulation results indicate that the performance of the AHV with the LPDP controller is improved by decreasing rearward amplification ratio from the baseline value of 1.28 to 0.98 and reducing transient off-tracking by 95.03%. The proposed LPDP control algorithm provides an alternative method for the design optimization of AHVs with ATS systems. 相似文献
995.
Bashir Ahmmad Kwati Leonard Md. Shariful Islam Junichi Kurawaki Manickavachagam Muruganandham Takahiro Ohkubo Yasushige Kuroda 《Advanced Powder Technology》2013,24(1):160-167
A green synthesis method for the preparation of mesoporous α-Fe2O3 nanoparticles has been developed using the extract of green tea (camellia sinensis) leaves. This simple and one-step method can suitably be scaled up for large-scale synthesis. The as-prepared mesoporous nanoparticles were characterized by SEM, TEM, XRD, XPS, Raman, UV–visible spectroscopy and N2 adsorption analysis. The nanoparticles were highly pure and well crystallized with an average particle size of 60 nm. The photocatalytic activity of nanoparticles was evaluated by the amount of hydroxyl radical formation under visible light irradiation detected by fluorescence spectroscopy. The as-prepared α-Fe2O3 showed two times higher activity than commercial α-Fe2O3 in term of hydroxyl radical formation and enhanced performance in a photoelectrochemical cell. Also, a plausible mechanism for the formation of mesoporous α-Fe2O3 has been suggested. 相似文献
996.
Muhammad Zafrullah Muhammad Bilal Iqbal Muhammad Rameez Asif Muhammad Khawar Islam 《Journal of Modern Optics》2013,60(21):1926-1930
Wavelength division multiplexing (WDM) systems, which are widely used in telecommunication, have the advantages of huge bandwidth support and reliability. A performance analysis is presented of a WDM system using an erbium-doped fiber amplifier (EDFA), with specific emphasis on bit error rate (BER) optimization. EDFA parameters, including doped fiber length and pump power, are optimized and performance evaluating parameters for different modulation schemes are observed. Simulation results provide optimized BER, noise figure, and gain flatness values. The WDM system is modeled from 1546 nm to 1558 nm bandwidth to obtain maximum gain uniformity, low noise figure, and low BER. This wavelength range is selected to investigate the 1550 nm wavelength commonly used in the telecommunication industry. Also, that we are using a WDM grid, so multiple channels can be accommodated in this range. 相似文献
997.
Hafiz Muhammad Obaid Muhammad Khawar Islam Muhammad Obaid Ullah 《Journal of Modern Optics》2013,60(15):1500-1505
AbstractBroadband chaos can be generated by beating two wavelengths in a hybrid arrangement of Fabry–Perot (FP) Laser and Fiber ring cavity by injecting dual wavelengths. The bandwidth of generated chaos can be controlled by detuning different modes of FP Laser for beating. The bandwidth of generated chaos increased to many folds depending upon the injected strength and wavelength spacing matched to FP laser modes. The bandwidth enhancement in different simulation experiments conducted is optimized by varying different parameters of FP laser and cavity. The waveforms are analyzed and Lyapunov exponents are calculated in order to validate the existence of high bandwidth non-pulsating chaos. 相似文献
998.
999.
A selective flame atomic absorption spectrometric method has been developed for the determination of trace amount of metal ions after preconcentration on salicylic acid (SA) loaded Amberlite XAD‐4 resin (AXAD‐4) at suitable pH. The chelating resin AXAD‐4‐SA was characterized based on FTIR, thermal and chemical stability, and hydrogen ion capacity. The sorption capacity was found to be 245.0, 156.2, 155.0, 145.0, 125.0, 122.5, and 70 μmol g?1 for Cu(II), Cr(III), Zn(II), Cd(II), Mn(II), Ni(II), and Co(II), respectively with t1/2 <15 min. All the metals could be eluted by 5 mL of 4 mol L?1 HCl/HNO3 resulting in high preconcentration factor of 200–360 up to a low preconcentration limit of 5.5–10 μg L?1. The accuracy and precision of the developed method was checked by analyzing standard reference materials. The experimental values were not statistically significant from the certified values with <5% RSD. The detection limits were found to be 0.42, 0.57, 0.63, 0.77, 0.94, 0.96, and 1.41 μg L?1, respectively. The analytical utility of the AXAD‐4‐SA for preconcentration and determination of metal ions was explored by analyzing river, canal, sewage, and tap water by direct as well as standard addition method. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
1000.
Long Giang Bach Md. Rafiqul Islam Jin Ho Kim Hyun Gyu Kim Kwon Taek Lim 《应用聚合物科学杂志》2012,124(6):4755-4764
Disulfide‐bearing poly(2‐hydroxyethyl methacrylate) (DT‐PHEMA) was synthesized by atom transfer radical polymerization technique, which was subsequently immobilized onto core‐shell structured Fe‐Au nanoparticles (Fe‐AuNPs) by applying a “grafting to” protocol to afford new PHEMA‐grafted Fe‐AuNPs (PHEMA‐g‐Fe‐AuNPs). The Fe‐AuNPs having the iron core of 20–22 nm and the gold layer of 1–2 nm were initially prepared by inverse micelle technique and characterized by XRD and high‐resolution transmission electron microscopy (HR‐TEM). The grafting of DT‐PHEMA on the Fe‐AuNPs was confirmed by Fourier transformed infrared spectrophotometer, thermogravimetric (TGA), X‐ray photoelectron spectroscopy, and energy dispersive X‐ray analyses. The average diameter of polymer coated Fe‐AuNPs was determined to be 28 nm by HR‐TEM analysis. The amount of the polymer on the surface of Fe‐AuNPs was calculated to be about 50% by TGA analysis. The studies of magnetic property by the superconducting quantum interference devices indicate the superparamagnetic property of Fe‐AuNPs and PHEMA‐g‐Fe‐AuNPs. The optical property of the PHEMA‐g‐Fe‐AuNPs was recorded by UV–visible absorption spectroscopy, and a redshift in the absorption was observed, which further suggests the PHEMA attachment on the surface of Fe‐AuNPs. The magnetic nanocomposites demonstrate good dispersibility in common polar solvents. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献