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Ebrahimi A.,Toosi University of Technology | Ehteshami M.,K. N. Toosi University of Technology | Dahrazma B.,University of Shahrood
Process Safety and Environmental Protection | Year: 2015

Cadmium is an extremely toxic metal commonly found in industrial regions. Anthropogenic activity is the most important factor causing its interference to water, soil and air resources. The aim of many researches is to present remediation strategy or to remove cadmium from contaminated resources through an economical and efficient method. Cadmium adsorption from aqueous solution using Alhaji maurorum seed adsorbent has been investigated and optimized in this study. Moreover, isotherm and kinetics of adsorption process was studied. The seeds are washed by distilled water after separation from the plant, and then dried in room temperature for 48 h. They are powdered by grinder and passed through sieve no.18 as well. Adsorption process was optimized in 4 steps regarding pH, contact time, adsorption dose and initial concentration of cadmium effects. The cadmium concentration in solution was measured using ICP-OES method. The results of optimization tests showed that the optimum condition of cadmium adsorption (85.5% removal) occurs at pH of 6.5 with 20 g/L of adsorption dose for 45 min. In addition, the efficiency of adsorption process increases as the cadmium concentration reduces in the initial solution. Adsorption process follows the pseudo second-order kinetics and Freundlich isotherm with correlation coefficients of 0.999 and 0.99, respectively. According to the findings of this analysis, it was concluded that A. maurorum seed is a good biological adsorbent for adsorbing cadmium from aqueous solution. © 2015 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved. Source


Alimohammadi A.,Toosi University of Technology
Transactions in GIS | Year: 2015

Residential location choice modeling is one of the substantial components of land use and transportation models. While numerous aggregated mathematical and statistical approaches have been developed to model the residence choice behavior of households, disaggregated approaches such as the agent-based modeling have shown interesting capabilities. In this article, a novel agent-based approach is developed to simulate the residential location choice of tenants in Tehran, the capital of Iran. Tenants are considered as agents who select their desired residential alternatives according to their characteristics and preferences for various criteria such as the rent, accessibility to different services and facilities, environmental pollution, and distance from their workplace and former residence. The choice set of agents is limited to their desired residential alternatives by applying a constrained NSGA-II algorithm. Then, agents compete with each other to select their final residence among their alternatives. Results of the proposed approach are validated by comparing simulated and actual residences of a sample of tenants. Results show that the proposed approach is able to accurately simulate the residence of 59.3% of tenants at the traffic analysis zone level. © 2015 John Wiley & Sons Ltd. Source


Azimi V.,Islamic Azad University at South Tehran | Nekoui M.A.,Toosi University of Technology | Fakharian A.,Islamic Azad University at Qazvin
Proceedings of the Institution of Mechanical Engineers. Part I: Journal of Systems and Control Engineering | Year: 2012

In this paper a robust H2/H∞ multi-objective state-feedback controller and tracking design are presented for a class of multiple input/multiple output nonlinear uncertain systems. First, some states (error of tracking) are augmented to the system in order to improve tracking control. Next, uncertain parameters and the quantification of uncertainty on physical parameters are defined by the affine parameter-dependent systems method. Then, to apply the H2/H∞ controller, the uncertain nonlinear system is approximated by the Takagi-Sugeno fuzzy model. After that, based on each local linear subsystem with augmented state, an H 2/H∞ multi-objective state-feedback controller is designed by using a linear matrix inequalities approach. Finally, parallel distributed compensation is used to design the controller for the overall system and the total linear system is obtained by use of the weighted sum of the local linear subsystems. Several results show that the proposed method can effectively meet performance requirements such as robustness, good load disturbance rejection, good tracking and fast transient responses for a three-phase interior permanent magnet synchronous motor system. © 2012 IMechE. Source


News Article
Site: http://www.nanotech-now.com/

Home > Press > New Nanosorbent Detects Tiny Amounts of Anticancer Drugs in Body Abstract: Iranian researchers from K. N. Toosi University of Technology produced a new nanosorbent to detect very low amount of anticancer drugs in biological samples. Higher speed, lower cost and ease of access are among the important advantages of the nanosorbent to be used in laboratory diagnosis methods. The production of appropriate sorbents with high efficiency and simple and cost-effective synthesis methods for the pre-concentration and extraction of drugs at very small amount (which is not directly measureable with other devices) from biological samples and the analysis of drugs by using devices will help the treatment of patients who suffer from cancer. Therefore, metal-organic frameworks/polymer composite nanofibers were produced in this research through a very simple and cost-effective electrospinning method. Then, the performance of these nanofibers was investigated in the detection of very small amount of megestrol acetate and levonorgestrel though solid phase extraction method in biological samples. In this research, fibrous nanosorbents were synthesized by using metal-organic frameworks/polyacrylonitrile through electrospinning method. The nanosorbent can measure very small amounts of asteroid drugs in complex tissues without the need for advanced devices due to its high sorption capacity and high pre-concentration functions. Test results showed that this method has a better performance in the detection of the drug in comparison with similar methods, and it requires less organic solvents and sorbents. Results of the research have been published in Journal of Chromatography A, vol. 1426, 2015, pp. 24-32. For more information, please click If you have a comment, please us. Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.


Shirzadi Babakan A.,Toosi University of Technology | Alimohammadi A.,Toosi University of Technology
Transactions in GIS | Year: 2016

Residential location choice modeling is one of the substantial components of land use and transportation models. While numerous aggregated mathematical and statistical approaches have been developed to model the residence choice behavior of households, disaggregated approaches such as the agent-based modeling have shown interesting capabilities. In this article, a novel agent-based approach is developed to simulate the residential location choice of tenants in Tehran, the capital of Iran. Tenants are considered as agents who select their desired residential alternatives according to their characteristics and preferences for various criteria such as the rent, accessibility to different services and facilities, environmental pollution, and distance from their workplace and former residence. The choice set of agents is limited to their desired residential alternatives by applying a constrained NSGA-II algorithm. Then, agents compete with each other to select their final residence among their alternatives. Results of the proposed approach are validated by comparing simulated and actual residences of a sample of tenants. Results show that the proposed approach is able to accurately simulate the residence of 59.3% of tenants at the traffic analysis zone level. © 2016 John Wiley & Sons Ltd. Source

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