Islamic Azad University

About: Islamic Azad University is a education organization based out in Tehran, Iran. It is known for research contribution in the topics: Population & Catalysis. The organization has 83635 authors who have published 113437 publications receiving 1275049 citations. The organization is also known as: Azad University.

Designing graphene-wrapped nanoporous CuCo2O4 hollow spheres electrodes for high-performance asymmetric supercapacitors

Abstract: Increasing demand for green energy storage systems, arising from the rapid development of portable electronics, has triggered tremendous research efforts for designing new or high-performance electrodes. Herein, for the first time, we develop a graphene-wrapped CuCo2O4 hollow spheres electrodes with a 3D composite network, a high surface area of 106.2 m2 g−1 and nanopores mainly centred at 7.6 nm. This electrode exhibits excellent electrochemical performance with an ultrahigh specific capacitance of 1813 F g−1 at 2 A g−1 (3.63 F cm−2 at 4 mA cm−2) and a significant rate capability of 63% capacitance retention even at an ultrafast rate of 120 mA cm−2. Utilizing this nanocomposite as the positive electrode in a GW-CuCo2O4//rGO asymmetric configuration results in the development of devices with remarkable performance including excellent cycle life (4.8% loss after 6000 cycles), a maximum energy density of 45.2 W h kg−1 and a power density up to 15 kW kg−1, which is superior to state-of-the-art supercapacitors. The superior electrochemical performance of this electrode is attributed to the synergic effects between the components and its unique 3D nanoporous composite network that plays a key role in providing high conductivity, rich redox reactions, facile electron transfer, short ion diffusion distance, fast kinetics and great active sites for electrochemical reactions. This study presents a new platform for unique and efficient electrodes for the next generation of high-performance energy storage systems and portable electronics.

Prioritizing quantitative trait loci for root system architecture in tetraploid wheat.

Abstract: Optimization of root system architecture (RSA) traits is an important objective for modern wheat breeding. Linkage and association mapping for RSA in two recombinant inbred line populations and one association mapping panel of 183 elite durum wheat (Triticum turgidum L. var. durum Desf.) accessions evaluated as seedlings grown on filter paper/polycarbonate screening plates revealed 20 clusters of quantitative trait loci (QTLs) for root length and number, as well as 30 QTLs for root growth angle (RGA). Divergent RGA phenotypes observed by seminal root screening were validated by root phenotyping of field-grown adult plants. QTLs were mapped on a high-density tetraploid consensus map based on transcript-associated Illumina 90K single nucleotide polymorphisms (SNPs) developed for bread and durum wheat, thus allowing for an accurate cross-referencing of RSA QTLs between durum and bread wheat. Among the main QTL clusters for root length and number highlighted in this study, 15 overlapped with QTLs for multiple RSA traits reported in bread wheat, while out of 30 QTLs for RGA, only six showed co-location with previously reported QTLs in wheat. Based on their relative additive effects/significance, allelic distribution in the association mapping panel, and co-location with QTLs for grain weight and grain yield, the RSA QTLs have been prioritized in terms of breeding value. Three major QTL clusters for root length and number (RSA_QTL_cluster_5#, RSA_QTL_cluster_6#, and RSA_QTL_cluster_12#) and nine RGA QTL clusters (QRGA.ubo-2A.1, QRGA.ubo-2A.3, QRGA.ubo-2B.2/2B.3, QRGA.ubo-4B.4, QRGA.ubo-6A.1, QRGA.ubo-6A.2, QRGA.ubo-7A.1, QRGA.ubo-7A.2, and QRGA.ubo-7B) appear particularly valuable for further characterization towards a possible implementation of breeding applications in marker-assisted selection and/or cloning of the causal genes underlying the QTLs.

Biosynthesis of ZnO Nanoparticles by a New Pichia kudriavzevii Yeast Strain and Evaluation of Their Antimicrobial and Antioxidant Activities.

Abstract: The potential ability of a new yeast strain, Pichia kudriavzevii, in the synthesis of zinc oxide nanoparticles (ZnO-NPs) through a green method was explored in this study The effect of reaction time (12, 24 and 36 h) on the structure of the resulting ZnO nanoparticles was investigated From the XRD and TEM results, the ZnO-NPs with a hexagonal wurtzite structure and a particle crystal size of ~10–61 nm was formed at different reaction times Combing XRD, TEM, and PL results, it was revealed that the sample prepared at intermediate duration (24 h) has the most favorable nanosized structure with the lowest defect concentration The biomedical properties of ZnO-NPs as free radical scavenging activity, cytotoxicity and antibacterial agents were characterized Biosynthesized ZnO-NPs showed strong DPPH free radical scavenging and a dose dependent toxicity with non-toxic effects on Vero cells for concentrations below 190 µg/mL Desirable bactericidal activity was shown by the ZnO-NPs on Gram-positive bacteria (Bacillus subtilis, Staphylococcus epidermidis and Staphylococcus aurous) and Gram-negative bacteria (Escherichia coli and Serratia marcescens) A maximum inhibition zone of ~19 mm was observed for Staphylococcus epidermidis at a concentration of 100 µg/mL for sample prepared at 24 h The results from this study reveal that ZnO-NPs possesses potential for many medical and industrial applications

Comparison of photocatalytic efficiency of supported CuO onto micro and nano particles of zeolite X in photodecolorization of Methylene blue and Methyl orange aqueous mixture

Abstract: The present study compares the photocatalytic decolorization ability of CuO as supported onto both micronized zeolite X (CuO/MX) and zeolite X nano-particles (CuO/NX) toward aqueous mixture of Methyl Orange (MO) and Methylene Blue (MB). Both photocatalysts were characterized by XRD, SEM, BET, FT-IR and DRS. The progress of the photodecolorization of the proposed mixture was monitored using UV–vis spectrophotometer. The decolorization of dyes was systematically studied by varying the experimental parameters in order to achieve maximum decolorization efficiency. Application of the Langmuir–Hinshelwood kinetics allowed calculating the photodecolorization rate constants. CuO/NX was more efficient than CuO/MX and also, MO was more degraded than MB. The reusability of the photocatalyts was also tested and the decolorization activities of 90% and 88% were respectively obtained for CuO/NX and CuO/MX after four recycles.