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101.
Nasrollazade Fateme Moghadam Meisam Nesary Pourmina Mohammad Ali 《Wireless Personal Communications》2022,126(2):1345-1361
Wireless Personal Communications - Security in vehicular ad hoc network (VANET) is one of the major challenging topics and the secure key interchange between two legitimate vehicles is an important... 相似文献
102.
In this research, adsorption technique was applied for strontium and barium removal from aqueous solution using dolomite powder. The process has been investigated as a function of pH, contact time, temperature and adsorbate concentration. The experimental data was analyzed using equilibrium isotherm, kinetic and thermodynamic models. The isotherm data was well described by Langmuir isotherm model. The maximum adsorption capacity was found to be 1.172 and 3.958 mg/g for Sr(II) and Ba(II) from the Langmuir isotherm model at 293 K, respectively. The kinetic data was tested using first and pseudo-second order models. The results indicated that adsorption fitted well with the pseudo-second order kinetic model. The thermodynamic parameters (ΔG°, ΔH°, and ΔS°) were also determined using the equilibrium constant value obtained at different temperatures. The results showed that the adsorption for both ions was feasible and exothermic. 相似文献
103.
104.
Meisam Torab-Mostaedi Ahad GhaemiMehdi Asadollahzadeh 《Chemical Engineering Research and Design》2011,89(12):2742-2751
The hydrodynamic behavior of a pulsed disc and doughnut column has been investigated using three different systems in the absence of mass transfer. Sauter-mean drop diameter (d32), flooding velocity and holdup at flooding have been measured at different operating conditions. The following operating variables have been studied: pulsation intensity and flow rate of both liquid phases. As expected, smaller mean drop sizes are obtained with the increase of pulsation intensity. The results also show no significant effect of continuous phase flow rate on mean drop size, which increases with increase of dispersed phase flow rate for the operating conditions investigated. A single correlation for the prediction of d32 in the mixer-settler, transition and emulsion regimes of operation is proposed with a mean deviation of 7.32%. The maximum throughput is influenced mainly by pulsation intensity and interfacial tension. Two precise correlations are proposed for predicting flooding velocities in this column. The first is based on operating variables, column geometry, and system physical properties. The second one considers the same variables, except column geometry. Good agreement between prediction and experiments is found for all operating conditions investigated. 相似文献
105.
Rezvan Torkaman Meisam Torab-Mostaedi Jaber Safdari Mohammad Ali Moosavian 《稀有金属(英文版)》2016,35(6):487-494
The extraction kinetics of Gd(III) from the nitric acid medium using bis(2,4,4-trimethylpentyl) dithiophosphinic acid (Cyanex301) and 2-ethylhexyl phosphoric acid (D2EHPA) in kerosene solution were measured by the single drop technique. The influences of hydrogen ion concentration, gadolinium ion concentration, extractant concentration, column height, and nozzle diameter on the extraction rate were investigated. The forward rate equations for the gadolinium extraction with D2EHPA and Cyanex301 were obtained. Based on the experimental results, the forward extraction rate constant was calculated. With the increase of D2EHPA or Cyanex301 concentration, the drop rising diameter and the value of interfacial tension decrease in the studied system, which shows that D2EHPA or Cyanex301 has interfacial activity as a kind of surfactant. Also, the droplet diameter and interfacial tension decrease with the increase of aqueous solution acidity. The experimental results show that the D2EHPA extractant provides faster extraction rate in comparison with Cyanex301 extractant, and it would be useful in industrial continuous extraction process. 相似文献
106.
Mohammad Mahdi A. Shirazi Meisam Tabatabaei 《Chemical Engineering Communications》2013,200(4):457-466
This article considers the application of the sweeping gas membrane distillation process (SGMD) for direct separation of ethanol-water using a flat sheet PTFE membrane. It also studies the effect of operating parameters including feed concentration, feed temperature, feed flow rate, and sweeping gas flow rate on the permeation flux and selectivity of ethanol/water. The results showed that the increase in feed temperature increases in permeate flux and selectivity. Selectivities of 18.5 to 25 were achieved using dilute feeds within the temperature range of 35 to 55°C. However, by increasing the feed concentration by more than 5 wt.%, the selectivity was decreased. The increase in permeation flux and ethanol selectivity at higher feed flow rates was mainly due to the reduction of polarization effects. Moreover, the PTFE membrane was characterized by AFM. The results showed that the present process could be used as a stand-alone technique for bioethanol process integration. 相似文献
107.
Nonsingular Terminal Sliding Mode Control With Ultra-Local Model and Single Input Interval Type-2 Fuzzy Logic Control for Pitch Control of Wind Turbines 下载免费PDF全文
Saber Abrazeh Ahmad Parvaresh Saeid-Reza Mohseni Meisam Jahanshahi Zeitouni Meysam Gheisarnejad Mohammad Hassan Khooban 《IEEE/CAA Journal of Automatica Sinica》2021,8(3):690-700
As wind energy is becoming one of the fastestgrowing renewable energy resources,controlling large-scale wind turbines remains a challenging task due to its system model nonlinearities and high external uncertainties.The main goal of the current work is to propose an intelligent control of the wind turbine system without the need for model identification.For this purpose,a novel model-independent nonsingular terminal slidingmode control(MINTSMC)using the basic principles of the ultralocal model(ULM)and combined with the single input interval type-2 fuzzy logic control(SIT2-FLC)is developed for non-linear wind turbine pitch angle control.In the suggested control framework,the MINTSMC scheme is designed to regulate the wind turbine speed rotor,and a sliding-mode(SM)observer is adopted to estimate the unknown phenomena of the ULM.The auxiliary SIT2-FLC is added in the model-independent control structure to improve the rotor speed regulation and compensate for the SM observation estimation error.Extensive examinations and comparative analyses were made using a real-time softwarein-the-loop(RT-SiL)based on the dSPACE 1202 board to appraise the efficiency and applicability of the suggested modelindependent scheme in a real-time testbed. 相似文献
108.
Recent studies demonstrated that oxygen-active elements such as yttrium improved the resistance of some alloys to wear and
corrosive wear. In this work, the breakdown of passive film and chemical resistance of the passive film in Y-free and Y-containing
6061 aluminum alloy samples were studied. It was demonstrated that critical load that caused failure of the passive film on
Y-containing specimens was higher than Y-free samples. Also, penetration depth showed that indentation resistances of Y-containing
samples were less than Y-free samples. Polarization behavior of Y-containing samples was improved in contrast of Y-free samples
in water and acid environments. Y-containing samples had more power to stabilize the oxide film and make it more inert to
electron transfer. Results showed that there was an optimum yttrium addition for improving the properties of Al 6061. Results
showed that the best percent of yttrium addition was between 1.5 and 4% and more than this the properties of alloy did not
improved 相似文献
109.
Hafizi M. Shen Feng Taoling Fu Schulze K. Ruth R. Schwab R. Karlsen P. Simmonds D. Qizheng Gu 《Solid-State Circuits, IEEE Journal of》2004,39(10):1622-1632
We report on the front-end of a highly integrated dual-band direct-conversion receiver IC for cdma-2000 mobile handset applications. The RF front-end included a CELL-band low-noise amplifier (LNA), dual-band direct-conversion quadrature I/Q down-converters, and a local-oscillator (LO) signal generation circuit. At 2.7 V, the LNA had a noise figure of 1.2 dB and input third-order intermodulation product (IIP3) of 9 dBm. I/Q down-converters had a noise figure of 4-5 dB and IIP3 of 4-5 dBm and IIP2 of 55 dBm. An on-chip phase-locked loop and external voltage-controlled oscillator generated the LO signal. The receiver RFIC was implemented in a 0.35-/spl mu/m SiGe BiCMOS process and meets or exceeds all cdma-2000 requirements when tested individually or on a handset. 相似文献
110.
Meisam Amiri Mohsen Esfahanian Mohammad Reza Hairi-Yazdi Vahid Esfahanian 《Journal of power sources》2009,190(2):372-379
Hybrid Electric Vehicles (HEVs) are becoming more popular than pure electric ones, nowadays. This is because of their better performance, economic advantages and higher operating range. However, their potential advantages extremely depend on their system design, most importantly their battery system design. Batteries’ life requirements as well as the cost of replacing them at the end of their life period, currently limit manufacturers to bring HEVs into play, even though their fuel economy reduces their everyday cost considerably. Generally, inappropriate discharge/charge patterns would result in loss in batteries’ life. In the present study, an optimization based control strategy has been proposed for the series HEVs in order to maximize the efficiency of the power-train while minimizing the loss. A genetic algorithm is implemented to optimally evaluate the control algorithm's parameters. The approach is then compared to two main control strategies, namely thermostatic control strategy and power follower control strategy. The computational procedure of the genetic algorithm is discussed, and a simulation study based on a model of a series hybrid electric vehicle is given to validate the genetic algorithm results. 相似文献