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The present study highlights the first time use of hybrid synergy electrocatalysis to design a cost effective, non-enzymatic ethanol sensor. The nanohybrid has been synthesized by decorating platinum palladium bimetallic nanoparticles (Pt-PdNPs) on graphene nanosheets (G/Pt-PdNPs). Field emission scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, electrochemical measurements and UV-Vis spectrophotometry have been used to characterize the nanocomposite. An ethanol oxidation current of 332 [micro]A was obtained with the use of G/Pt- PdNPs modified glassy carbon electrode (GCE) that is 167 times higher than that of bare GCE in cyclic voltammetry studies with a potential scan rate of 50 mV/s in 0.1 M NaOH as the supporting electrolyte. Chronoamperometry studies have shown a distinct increase in the current for increasing concentration of ethanol with a wide range of linearity extending from 5 mM to 3 M and a detection limit of 1 mM with the use of G/Pt- PdNPs. Quantum mechanical modeling using density functional theory was used to arrive at the minimization energies of G/Pd, G/Pt and G/Pt-Pd in the presence and absence of ethanol. The improved catalytic activity of G/Pt-PdNPs nanocomposite for ethanol detection is on account of the cooperative effects of Pt and PdNPs, coupled with the high conducting nature of graphene. Keywords: ethanol sensor, graphene, palladium, platinum DOI: 10.1134/S1061934818030073, Ethanol determination plays an important role in medicine, forensic science, brewing, food fermentation, beverage industry, clinical laboratory and traffic safety [1]. Therefore development of a sensitive and selective ethanol sensor [...]

A revised formulation of the image light distribution of an incoherent line source proposed by Steel [Rev. Opt. 31, 334-340 (1952)] is presented. Analytical and numerical results based on this new representation are given. We explicitly show that a major error in Steel's final expression generates singularities, thereby preventing convenient numerical computation.

The electron-rich media of two different triphenylene-based columnar hexagonal liquid-crystalline phases were utilized to study the dispersion of electron-deficient ferrocenium ions. A charge-transfer complex is formed between the electron-rich discotic molecules and the electron-deficient ferrocenium ions.

Nossuli, T. O., V. Lakshminarayanan, G. Baumgarten, G. E. Taffet, C. M. Ballantyne, L. H. Michael, and M. L. Entman. A chronic mouse model of myocardial ischemia-reperfusion: essential in cytokine studies. Am J Physiol Heart Circ Physiol 278: H1049-H1055, 2000.--Reperfusion of the ischemic myocardium is associated with a cytokine cascade that reflects a cellular response to injury. We studied this cascade in the mouse and found that acute surgical trauma in sham-operated animals obscured early changes in cytokine induction that occur during myocardial ischemia-reperfusion (MI/R). Therefore, we utilized a new implantable device that allows occlusion and reperfusion of the left anterior descending coronary artery in a closed-chest mouse at any time after instrumentation. Induction of interleukin (IL)-6 and tumor necrosis factor (TNF)-[Alpha] mRNA in the whole heart was examined by RNase protection assay and quantitated by Phosphor-Imager. At 3 h after instrumentation, levels of IL-6 mRNA in sham-operated animals increased above those of control naive hearts, whereas this increase did not occur until after 1 day for TNF-[Alpha] mRNA. The surgical trauma led to exaggeration of I/R cytokine induction with greater variance in response. At 3 days and 1 wk after instrumentation, levels of both IL-6 and TNF-[Alpha] mRNA in sham-operated animals were comparable to those of naive hearts and induction responses in I/R were much less variant. We also found that 1 h of ischemia and 2 h of reperfusion at all time points of recovery (i.e., 3 h and 1, 3, and 7 days after instrumentation) led to a significant increase in IL-6 and TNF-[Alpha] mRNA levels. In addition, 3 h of permanent occlusion, which did not induce any mRNA increase after 1 wk postinstrumentation, caused marked upregulation of IL-6 mRNA in an acutely prepared animal. This study of early cytokine responses evoked by MI/R highlights the need for dissipation of acute surgical trauma by using a chronic, closed-chest mouse preparation. murine; cytokine; interleukin; inflammation; surgery