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Showing 4 results for Kalaee
Optimization of anti- Corrosion of Epoxy/Zinc Phosphate and Nano Silica coating

Volume 4, Issue 2 (Summer 2020)
Abstract
Research subject: In this research we studied the anti-corrosion properties of epoxy coating containing anti-corrosion pigment zinc phosphate with hydrophobic nano silica with different percentage also for determine the optimal conditions for preparation of nanocomposite Taguchi experimental design method was used.
 
Research approach: Anti-corrosion properties of epoxy coating under the influence of very important factors such as the percentage of nano silica, anticorrosive pigment and pigment to resin ratio according to model L9 taguchi method was studied and analyzed. Anti-corrosion properties of epoxy coatings were studied by electrochemical impedance spectroscopy test (EIS) in 3/5% NaCl aqueous solution and salt fog test (salt spray). To investigate the distribution of nano silica particles in epoxy resin were analyzed by transmion electron microscope (TEM) and scanning electron microscope (SEM). The results show that using from zinc phosphate and nano-silica was able to improve the corrosion resistances.
 
Main results:Results shows that addition of zinc phosphate and nano silica to epoxy resin caused a decrease in number of blisters and corrosion products after exposure to corrosion test based on the results in Nyquist and Bode plots, also the similarity in results was observed for the epoxy coating loaded according to the optimum conditions with 8% zinc phosphate, 3% nano silica and pigment to resin ratio of one according to salt spary. The significance levels of the experimental parameters, which indicate how the factors affect the compressive addition of zinc phosphate and nano silica to epoxy resin, were determined by using variance (Anova) method.


Effect of Temperature Variation and Mass Distribution on the Optimal Design of the Constrained-Layer-Damping for a Beam

Volume 20, Issue 3 (March 2020)
Abstract
In this research, the vibration of a beam treated with a viscoelastic constrained-layer-damping has been studied and the effects of thermal variations and the attached lumped mass on the variation of the optimal design of the constrained layer have been investigated. For modeling the core, the second and third order polynomials were used respectively for out-of-plane and in-plane displacements, and for outer layers, the Euler-Bernoulli beam theory was used. With this modeling, the effect of the through-the-thickness normal strain in the mid-layer (core) can be included in the analyses, and the model will be applicable for studying the cases with moderately thick cores. The finite element method with 3-node elements has also been used for the solution purpose. Moreover, the viscoelastic material is assumed to be isotropic and its constitutive behavior is described by a complex shear modulus dependent on temperature and frequency. This dependence on frequency and temperature has been obtained by using the graphs of the experimental results presented in the relevant references. Numerical studies have been carried out to investigate the variation of the damping and harmonic response amplitude with the thickness of the core and the constraining layer at different temperatures. The results showed that the thermal variation could considerably change the region associated with the optimal design and the maximum damping. This implies that the range of thermal variations in the operating environment of the structure should be considered in designing a viscoelastic-damping layer. In the numerical studies, the effect of added rigid masses on changing the optimal design was investigated. The results show the necessity to consider all the added masses before designing the constrained layer damping.

Resistance of Nine Wheat Cultivars and Lines to Greenbug, Schizaphis graminum (Rondani) in Iran
M. Mohammadi Anaii, M. Pahlavan Yali, M. Bozorg Amir-Kalaee,
Volume 20, Issue 6 (11-2018)
Abstract
Greenbug, Schizaphis graminum (Rondani), is the main pest of wheat that can considerably limit profitable crop production, either through direct feeding or via transmission of plant pathogenic viruses. One of the most effective approaches of pest control is the use of resistant cultivars and lines. Based on the initial screening test of 35 wheat cultivars and lines, we selected five cultivars (Pishtaz, Omid, Yavaras, Akbari, and Bahar) and four lines (R1-10, R2-9, R3-16, and R3-17) with different levels of resistance to S. graminum for antixenosis and antibiosis experiments. In the antixenosis test, the number of S. graminum attracted on R1-10 was the lowest after 24, 48, and 72 hours. In life table study, S. graminum reared on Yavaras and R1-10 had the lower survival rate, fecundity, and reproductive period compared with other host plans tested. Values of the intrinsic rate of natural increase (rm), finite rate of increase (λ), net Reproductive rate (R0), and Doubling Time (DT) indicated lowest population growth of S. graminum, when fed on Yavaras (0.26 d-1, 1.30 d-1, 17.66 offspring and 2.62 days, respectively). Based on the antixenosis and antibiosis analyses in this study, we concluded that R1-10 and Yavaras were more resistant to S. graminum. These findings could be useful for integrated pest management of S. graminum in wheat fields.
 
Role of Exogenous Elicitors in Canola Plant Defense against Cabbage Aphid by Regulating Physiological Balance and Secondary Metabolite Biosynthesis
M. Shahrokhy, M. Pahlavan Yali, M. Bozorg-AmirKalaee,
Volume 26, Issue 1 (1-2024)
Abstract
Induced resistance in plants can be manipulated using the application of elicitors. In this study, the effects of Salicylic Acid (SA), chitosan, γ-Aminobutyric Acid (GABA), Serenad Aso (Bacillus subtilis QST713), and combined application of these elicitors were studied on the resistance of canola to cabbage aphid, Brevicoryne brassicae L. (Hemiptera: Aphididae). The number of B. brassicae attracted to canola plants treated with different inducers was significantly lower compared to the control in the field experiments. The lowest population density of aphid was observed on plants treated with SA+GABA and SA+chitosan. Moreover, the highest amounts of glucosinolates in canola leaves were recorded in SA+GABA treatment. The contents of sugar, lipid, and glycogen of B. brassicae were lowest when fed on the plants treated with SA integrated with GABA or chitosan. Furthermore, the activity of catalase, esterase, peroxidase and glutathione S-transferase enzymes was the lowest in SA+GABA and SA+chitosan. These findings suggest that exogenous application of SA integrated with GABA or chitosan on canola plants are successful in suppressing the B. brassicae population and can be considered in integrated management programs against this and other aphids.
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