Synthesis, characterization and antimicrobial potential of transition metal complexes of triacetic lactone

Seven novel and biological active transition metal complexes were prepared using 3-nitro- 4-hydroxy -6-methyl-pyran-2-one derivative of triacetic lactone as ligand. These complexes were characterized by elemental analysis, magnetic susceptibility measurement, UV/Vis, FTIR and NMR spectroscopy. These data showed that solid complexes of Ni (II), Co (II), Mn (II), Zn (II) and Fe (II) indicated octahedral geometries while Cu (II) complex was assigned square planar geometry. The antimicrobial activities ofall above mentioned complexes along with ligand were tested against eleven different bacterial strains and ten fungal strains using agar well diffusion assay. Cu (II) complex showed highest inhibition zone against Shigella dysentriae (22.3 mm), greater than standard drug, while the Zn (II) complex showed maximum antifungal activity against Trichophyton simii (18.7 mm). The antimicrobial activities indicated that metal complexes showed enhanced activity as compared to the free ligand

Comparison of thermal interfacial performance of carbon nanofiller-based polymer composites

Extended Abstract deposited in White Rose Online Repositor

Antioxidant activities of the selected plants from the family Euphorbiaceae, Lauraceae, Malvaceae and Balsaminaceae

Extraction of nine plants selected from the family Euphorbiaceae, Lauraceae, Malvaceae and Balsaminaceae was done in petroleum ether, chloroform, ethyl acetate and methanol/n-butanol in order of increasing polarity using soxhlet apparatus. Total phenolic contents were determined with Folin- Ciocalteu reagent which ranged from 30.5 to 547.0 mg GAE/g of extract. Maximum phenolic contents were found in n-butanol extract of Ricinus communis. Antioxidant activities of these extracts were evaluated through DPPH• radical scavenging, phosphomolybdate and ferric thiocyanate (FTC) methods. Methanolic extract of Cinnamomum zeylanicum and Cinnamomum tamala showed highest antiradical (96.8%) and phosphomolybdate (1.131) activity, respectively, while ethyl acetate extract of R. communis exhibited maximum lipid per-oxidation (FTC) activity (79.3%). IC50 value of chloroform extract of C. tamala (2.2 g/ml) was less than gallic acid (4.4 g/ml), while ethyl acetate and methanol extracts of Abutilon bidentatum, Impatiens bicolor and Impatiens edgeworthii exhibited the IC50 values in the range of 10.0 - 20.0 g/ml

Fine Timing and Frequency Synchronization for MIMO-OFDM: An Extreme Learning Approach

Multiple-input multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) is a key technology component in the evolution towards cognitive radio (CR) in next-generation communication in which the accuracy of timing and frequency synchronization significantly impacts the overall system performance. In this paper, we propose a novel scheme leveraging extreme learning machine (ELM) to achieve high-precision synchronization. Specifically, exploiting the preamble signals with synchronization offsets, two ELMs are incorporated into a traditional MIMO-OFDM system to estimate both the residual symbol timing offset (RSTO) and the residual carrier frequency offset (RCFO). The simulation results show that the performance of the proposed ELM-based synchronization scheme is superior to the traditional method under both additive white Gaussian noise (AWGN) and frequency selective fading channels. Furthermore, comparing with the existing machine learning based techniques, the proposed method shows outstanding performance without the requirement of perfect channel state information (CSI) and prohibitive computational complexity. Finally, the proposed method is robust in terms of the choice of channel parameters (e.g., number of paths) and also in terms of "generalization ability" from a machine learning standpoint.Comment: 13 pages, 12 figures, has been accepted for publication in IEEE Transactions on Cognitive Communications and Networkin