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Tehran, Iran

Shahed University , was founded in 1990. The university started its activities by accepting 165 students in seven branches in 1991. It has currently more than 8000 students in 68 branches. Today Shahed university has 8 colleges and 7 Research Institutions. Now, like other prominent universities of Iran,it is one of the first options chosen by applicants in the annual nationwide entrance exam. Shahed University is located in the capital city of Tehran. The main campus is located in the southern part of Tehran along the Persian gulf Freeway. Wikipedia.

Omidi H.,Shahed University
American Journal of Plant Physiology | Year: 2010

The aim of present study was to get further information on the ability of drought stress applied to retard senescence and to frustrate inhibitory effects of drought-stress via comparing two canola genotypes differing in drought tolerance. The objective of this work was to evaluate the effects of the drought stress (control, -0.5, -1 and -1.5 Mpa) on two canola genotypes (Okapi and RGS). The experiment was factorial with four replications at experimental greenhouse at Center of Agriculture Research-Shahed, Iran, during 2006-2007. Morphological parameters of root and shoot dry weight, proline content osmolyte and enzyme activities of Ascorbate peroxidase (APx), Guaiacol peroxidase (GAx) and Catalase (Cat) in shoot and root of tissues canola genotypes were highly significant differences for main and interaction effects of two factors (Drought (D) and Genotype (G)) studied. Drought decreased the roots and shoots dry weight of canola plants and this effect was particularly significant at high level of stress. So, results indicated that proline content, ascorbate peroxidase (APx) and Guaiacol peroxidase (GAx) and Catalase (Cat) activity in root and shoot increased with enhancement of drought stress in the two genotypes. Of course, the proline content and antioxidant activities in Okapi genotype were more than RGS genotype. These results showed that Okapi genotype tolerated drought stress than RGS with increasing of proline content and antioxidant activities including GAx and APx. Shoot always maintained higher level of free Catalase (CAT) contents than the root. Therefore, the evaluation of both antioxidant enzymes and proline content can be suggested for Mechanisms of drought stress tolerance. © 2010 Academic Journals Inc. Source

Ghenaatian H.R.,Tarbiat Modares University | Mousavi M.F.,Tarbiat Modares University | Rahmanifar M.S.,Shahed University
Electrochimica Acta | Year: 2012

A hybrid asymmetric electrochemical supercapacitor is constructed by employing two different nanostructured conducting polymers of polypyrrole (PPy) and self-doped polyaniline (SDPA). Different electrochemical methods, including cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy (EIS), are performed to characterize the electrochemical performance of the supercapacitor. The maximal working potential window of 1.3 V is associated with more than 97 F g -1 of total electrode materials. The cell maintains approximately 70% of its initial capacitance after 1000 cycles with an equivalent series resistance (ESR) below 1.6 Ω cm 2. Furthermore, the system shows high specific energy, specific power and maximum power values of 22.87 Wh kg -1, 570 W kg -1 and 45,193 W kg -1, respectively, at a current density of 5 mA cm -2 in 1 M KCl. Long-life cycling is achieved by removing dissolved oxygen and using a mild pH electrolyte, which limits the redox activity of the electrically conducting polymers (ECPs). Moreover, the proposed supercapacitor exhibits high capacitance retention of 89% at a higher current density (40 mA cm -2), indicating good electrochemical stability and rate capability. The performance of the proposed hybrid supercapacitor has been compared with two other symmetric cells. © 2012 Elsevier Ltd. Source

Miransari M.,Shahed University
Applied Microbiology and Biotechnology | Year: 2011

With respect to the adverse effects of chemical fertilization on the environment and their related expenses, especially when overused, alternative methods of fertilization have been suggested and tested. For example, the combined use of chemical fertilization with organic fertilization and/or biological fertilization is among such methods. It has been indicated that the use of organic fertilization with chemical fertilization is a suitable method of providing crop plants with adequate amount of nutrients, while environmentally and economically appropriate. In this article, the importance of soil microbes to the ecosystem is reviewed, with particular emphasis on the role of plant growth-promoting rhizobacteria, arbuscular mycorrhizal fungi, and endophytic bacteria in providing necessary nutrients for plant growth and yield production. Such microbes are beneficial to plant growth through colonizing plant roots and inducing mechanisms by which plant growth increases. Although there has been extensive research work regarding the use of microbes as a method of fertilizing plants, it is yet a question how the efficiency of such microbial fertilization to the plant can be determined and increased. In other words, how the right combination of chemical and biological fertilization can be determined. In this article, the most recent advances regarding the effects of microbial fertilization on plant growth and yield production in their combined use with chemical fertilization are reviewed. There are also some details related to the molecular mechanisms affecting the microbial performance and how the use of biological techniques may affect the efficiency of biological fertilization. © 2011 Springer-Verlag. Source

Miransari M.,Shahed University
Biotechnology Advances | Year: 2011

Use of plants, with hyperaccumulating ability or in association with soil microbes including the symbiotic fungi, arbuscular mycorrhiza (AM), are among the most common biological methods of treating heavy metals in soil. Both hyperaccumulating plants and AM fungi have some unique abilities, which make them suitable to treat heavy metals. Hyperaccumulator plants have some genes, being expressed at the time of heavy metal pollution, and can accordingly localize high concentration of heavy metals to their tissues, without showing the toxicity symptoms. A key solution to the issue of heavy metal pollution may be the proper integration of hyperaccumulator plants and AM fungi. The interactions between the soil microbes and the host plant can also be important for the treatment of soils polluted with heavy metals. © 2011 Elsevier Inc. Source

Badri H.,Amirkabir University of Technology | Bashiri M.,Shahed University | Hejazi T.H.,Amirkabir University of Technology
Computers and Operations Research | Year: 2013

In the current competitive business world, viable companies are those that have flexible strategies and long-term plans, by which they can appropriately respond to a dynamic environment. These strategies are used to find the optimum allocation of company income to the main sources of development, for the expansion of company activities and for service expansions. This paper presents a new mathematical model for multiple echelon, multiple commodity Supply Chain Network Design (SCND) and considers different time resolutions for tactical and strategic decisions. Expansions of the supply chain in the proposed model are planned according to cumulative net profits and fund supplied by external sources. Furthermore, some features, such as the minimum and maximum utilisation rates of facilities, public warehouses and potential sites for the establishment of private warehouses, are considered. To solve the model, an approach based on a Lagrangian Relaxation (LR) method has been developed, and some numerical analyses have been conducted to evaluate the performance of the designed approach. © 2012 Elsevier Ltd. Source

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