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Reyes-Rodriguez J.L.,CINVESTAV | Sathish-Kumar K.,Polytechnic University of Aguascalientes | Solorza-Feria O.,CINVESTAV
International Journal of Hydrogen Energy | Year: 2015

This study investigates the synthesis and characterization of a carbon derived by a simple combustion process of natural camphor. Resulted carbon was subjected to a chemical (HNO3 and KOH) and physical treatment (thermal treatment -TT, liquid Nitrogen treatment - LN2) for surface functionalization. Synthesized carbon materials were used as Pt catalyst support for the oxygen reduction reaction (ORR) in acid media. Physicochemical characterization of the carbon support was performed by multiple techniques such as, SEM, EDAX, FTIR, and Raman spectroscopy. Results conducted to spherical particles of camphor carbon (CC) with 50-60nm in size. The chemical composition revealed a CC without sulfur content. This could be an advantage for avoiding the sulfur poisoning on the Pt surface. FTIR results shows that the oxidative chemical treatment (HNO3 and KOH) incorporate functional group of CO to CC. However, the TT eliminates the functional surface group on the CC. Apparently CC and CC-LN2 samples have the same behaviour, consequently it can be inferred that the cryogenic treatment with liquid nitrogen does not significantly modify the functional chemistry of carbon surface. Raman spectroscopy reveals the disorder in the CC (ID/IG=1.01) which is lesser than the Vulcan Carbon (ID/IG=1.16) defect. Furthermore, the chemically treated CC and LN2 shows fewer defects than the thermally treated CC. Electrochemical results show that materials with enhanced specific catalytic activity toward the ORR follow the tendency: Pt/CC-KOH>Pt/CC-TT>Pt/CC>Pt/CC-LN2>Pt/Vulcan>Pt/C Etek>Pt/CC-HNO3. Our finding results open a new avenue for carbon from natural source as an effective ORR catalyst support. © 2015 Hydrogen Energy Publications, LLC.

Vignesh V.,Bharathidasan University | Sathiyanarayanan G.,Bharathidasan University | Sathishkumar G.,Bharathidasan University | Parthiban K.,Bharathidasan University | And 2 more authors.
RSC Advances | Year: 2015

In the present study, we report the formulation, characterization, and in vitro antibacterial and cytotoxicity effects of exopolysaccharide (EPS) stabilized iron oxide nanoparticles (FeONPs) against the human epidermoid carcinoma cell line (A431). EPS is extracted from a spore-forming strain of Bacillus subtilis, VT03, isolated from the gut microbiome of the freshwater fish Oreochromis mossambicus (Tilapia). FTIR, 1H NMR and 13C NMR spectroscopic studies show the presence of sugar moieties, confirming that EPS might be a glucan. Later, EPS is used as an eco-friendly reducing and stabilizing agent for the formulation of iron oxide nanoparticles (FeONPs). Initially, the generation of nanoscale FeO was confirmed through the formation of a black-coloured precipitate with an absorbance maxima at 250-300 nm in a UV-visible spectrometer. X-ray diffraction (XRD) planes clearly confirm that the synthesized FeONPs are in the cubic spinel phase. The morphometric features of the synthesized FeONPs are exclusively studied using electron microscopy (FESEM and HRTEM) which shows spherical FeONPs in sizes ranging between 75-120 nm; the mean size was found to be 106 ± 12 nm. Additionally, energy dispersive X-ray analysis (EDAX), selected area emission diffraction (SAED) and dynamic light scattering (DLS) confirms the purity and homogeneity of the synthesized FeONPs. The vibrating sample magnetometer (VSM) technique reveals the presence of both ferro- and antiferromagnetic phases in the EPS-stabilized FeONPs. Further, the inhibitory activity of EPS-stabilized FeONPs against human and fish pathogenic strains such as Aeromonas hydrophila (ATCC 49140), Aeromonas hydrophila (MTCC 1739), Aeromonas sobria (MTCC 3613) and Aeromonas hydrophila (obtained from OIE Reference Laboratory, C. Abdul Hakeem College, Melvisharam) was assessed. The in vitro cytotoxicity effects of free EPS and EPS-stabilized FeONPs were probed in the human epidermoid carcinoma cell line A431. The IC50 values of EPS and EPS-stabilized FeONPs were found to be 350.18 and 62.946 μg ml-1 respectively. Further, acridine orange/ethidium bromide (AO/EtBr) staining of A431 cells at different time intervals clearly distinguishes the live cells and the cells that have undergone apoptotic cell death. In conclusion, our research paves the way for a facile and greener route to synthesize FeONPs at room temperature. On the other hand, this study also proves that the formulated multifunctional hybrid FeONPs have remarkable qualities such as enhanced bioavailability and magnetic properties. This can be developed into a successful theragnostic platform for cancer treatment. This journal is © The Royal Society of Chemistry 2015.

Ramachandran V.,Madurai Kamaraj University | Arumugasamy K.,Thiagarajar College of Engineering | Singh S.K.,Alagappa University | Edayadulla N.,Yeungnam University | And 2 more authors.
Journal of Chemical Biology | Year: 2016

The syntheses of dihydropyrimidinones (DHPMs) using solvent-free grindstone chemistry method. All the synthesized compounds exhibited significant activity against pathogenic bacteria. The current effort has been developed to obtain new DHPM derivatives that focus on the bacterial ribosomal A site RNA as a drug target. Molecular docking simulation analysis was applied to confirm the target specificity of DHPMs. The crystal structure of bacterial 16S rRNA and human 40S rRNA was taken as receptors for docking. Finally, the docking score, binding site interaction analysis revealed that DHPMs exhibit more specificity towards 16S rRNA than known antibiotic amikacin. Accordingly, targeting the bacterial ribosomal A site RNA with potential drug leads promises to overcome the bacterial drug resistance. Even though, anti-neoplastic activities of DHPMs were also predicted through prediction of activity spectra for substances (PASS) tool. Further, the results establish that the DHPMs can serve as perfect leads against bacterial drug resistance. © 2015, Springer-Verlag Berlin Heidelberg.

Villacorta H.,Polytechnic University of Aguascalientes | Villacorta H.,University of the Balearic Islands | Segura J.,University of the Balearic Islands | Champac V.,National Institute of Astrophysics, Optics and Electronics
Journal of Electronic Testing: Theory and Applications (JETTA) | Year: 2016

FinFET technology has become the most promising alternative to continue CMOS scaling due to its improved short channel effects. Design flexibility reduces on FinFET based circuits such as SRAM cells due to the effective channel width is determined by an integer number of fins. In this work, the impact of fin height size of FinFET transistors on the simultaneous behavior of soft error sensitivity and SRAM cell static noise margin is investigated. 3-D TCAD Sentarus environment is used to quantify the amount of collected and critical charges of an SRAM cell due to a heavy ion strike while Mix-Mode Hspice-TCAD simulation is used for stability analysis. Even more, the influence of process variations on sensitivity to soft errors and cell stability is considered. A 10 nm-SOI Tri-Gate FinFET technology is used. Results show that increasing the fin height of FinFET transistors considerably increases SRAM cell sensitivity to soft errors but improves its stability. This suggests that the optimum fin height value of FinFET transistors of an SRAM cell depends on the best tradeoff between soft error robustness and stability. © 2016, Springer Science+Business Media New York.

Rodriguez-Martinez L.C.,Aguascalientes Institute of Technology | Duran-Limon H.A.,University of Guadalajara | Mendoza-Gonzalez R.,Polytechnic University of Aguascalientes | Munoz J.,Autonomous University of Aguascalientes
Computer Science and Information Systems | Year: 2015

We identify a suite of activities in the development process of Graphical User Interfaces (GUI) and include them as part of an approach to a generic model for the GUI Development Process (GDP). This work contributes with: (1) the identification of common activities of previous GDPs, (2) the definition of an approach to a generic GDP limited to its phases and activities, and (3) the integration of such a generic GDP with any software-system development life cycle (SDLC), illustrated with the Spiral SDLC. We show this work is useful by a) highlighting the advantages of our proposal over other methodologies for GDP in Human-Computer Interaction (HCI), b) showing one example of the integration of the GDP into a SDLC, and c) showing the usefulness of our approach in a case example. © 2015, Computer Science and Information Systems. All rights reserved.

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