Graduate University of Advanced Technology

About: Graduate University of Advanced Technology is a education organization based out in Kerman, Iran. It is known for research contribution in the topics: Carbon paste electrode & Electrochemical gas sensor. The organization has 890 authors who have published 2169 publications receiving 31027 citations.

Synthesis and Characterization of Fluorapatite Nanoparticles Via a Mechanochemical Method

Abstract: Nanosized F-substituted hydroxyapatite (FA; Ca10(PO4)6(OH)2 − xFx) was synthesized with CaCO3, P2O5 and CaF2 as a precursor via a mechanochemical process. Different times of milling (10 min, 2, 4, 6, 8, 10, 12 and 14 h) and fluorine ion contents (0, 25, 50, 75 and 100 percent of substitution) were used to prepare the products. Transmission electron microscopy (TEM) analysis demonstrated that FA nanoparticles with an average diameter of 15–30 nm (at milling time of 10 h) were prepared. Finally, the bioactivity of optimal samples was investigated in simulated body fluid (SBF).

Effect of fin attachment on thermal stress reduction of exhaust manifold of an off road diesel engine

Abstract: The effect of fin attachment on the thermal stress reduction of exhaust manifold of an off road diesel engine (Komatsu HD325-6) was investigated. For doing this, coupled thermo-fluid-solid analysis of exhaust manifold of the off road diesel engine was carried out. The thermal analysis, including thermal flow, thermal stress, and the thermal deformation of the manifold was investigated. The flow inside the manifold was simulated and then its properties including velocity, pressure, and temperature were obtained. The flow properties were transferred to the solid model and then the thermal stresses and the thermal deformations of the manifold under different operating conditions were calculated. Finally, based on the predicted thermal stresses and thermal deformations of the manifold body shell, two fin types as well as body shell thickness increase were applied in the critical induced thermal stress area of the manifold to reduce the thermal stress and thermal deformation. The results of the above modifications show that the combined modifications, i.e. the thickness increase and the fin attachment, decrease the thermal stresses by up to 28% and the contribution of the fin attachment in this reduction is much higher compared to the shell thickness increase.

Morphometric comparisons of Diaphorina citri (Hemiptera: Liviidae) populations from Iran, USA and Pakistan

Abstract: The Asian citrus psyllid (ACP), Diaphorina citri Kuwayama (Hemiptera: Liviidae), vector of citrus greening disease pathogen, Huanglongbing (HLB), is considered the most serious pest of citrus in the world. Prior molecular based studies have hypothesized a link between the D. citri in Iran and the USA (Florida). The purpose of this study was to collect morphometric data from D. citri populations from Iran (mtCOI haplotype-1), Florida (mtCOI haplotype-1), and Pakistan (mtCOI haplotype-6), to determine whether different mtCOI haplotypes have a relationship to a specific morphometric variation. 240 samples from 6 ACP populations (Iran-Jiroft, Chabahar; Florida-Ft. Pierce, Palm Beach Gardens, Port St. Lucie; and Pakistan-Punjab) were collected for comparison. Measurements of 20 morphological characters were selected, measured and analysed using ANOVA and MANOVA. The results indicate differences among the 6 ACP populations (Wilks' lambda = 0.0376, F = 7.29, P < 0.0001). The body length (BL), circumanal ring length (CL), antenna length (AL), forewing length (WL) and Rs vein length of forewing (RL) were the most important characters separating the populations. The cluster analysis showed that the Iran and Florida populations are distinct from each other but separate from the Pakistan population. Thus, three subgroups can be morphologically discriminated within D. citri species in this study, (1) Iran, (2) USA (Florida) and (3) Pakistan population. Morphometric comparisons provided further resolution to the mtCOI haplotypes and distinguished the Florida and Iranian populations.

Silicon and nitric oxide synergistically modulate the production of essential oil and rosmarinic acid in Salvia officinalis under Cu stress.

Abstract: The individual impact of silicon (Si) and nitric oxide (NO) on secondary metabolism in several plant species has been reported, but their combined effect has never been evaluated yet. Therefore, in this study, single and combined impacts of NO and Si on the biosynthesis of rosmarinic acid (RA) and essential oil (EO) content in leaves of Salvia officinalis were investigated under both non-stress and Cu stress conditions. The results indicated that high Cu concentration decreased biomass and the content of polyphenols, but elevated electrolyte leakage, while lower Cu concentrations, especially 200 μM Cu, increased the content of polyphenols, EO, and antioxidant capacity in leaves of S. officinalis. The foliar application of sodium silicate (1 mM Si) and sodium nitroprusside (200 μM SNP as a NO donor) alone and particularly in combination improved shoot dry biomass, restored chlorophyll and carotenoids, increased EO content, the amounts of flavonoids, and phenolic compounds especially RA, and enhanced antioxidant capacity in the leaves of S. officinalis under both non-stress and Cu stress conditions. Copper treatment increased NO content, upregulated expression of PAL, TAT, and RAS genes, and enhanced phenylalanine ammonia-lyase activity in the leaves, which were responsible for improving the production of phenolic compounds, particularly rosmarinic acid. Foliar spraying with Si and SNP intensified these attributes. All responses were more pronounced when NO and Si were simultaneously applied under Cu stress. These findings suggest that NO and Si synergistically modulate secondary metabolism through upregulation of related gene expression and enzyme activities under both non-stress and Cu stress conditions.