We report on the improved field emission performance of graphene foam (GF) following transient exposure to hydrogen plasma. The enhanced field emission mechanism associated with hydrogenation has been investigated using Fourier transform infrared spectroscopy, plasma spectrophotometry, Raman spectroscopy, and scanning electron microscopy. The observed enhanced electron emissionhas been attributed to an increase in the areal density of lattice defects and the formation of a partially hydrogenated, graphane-like material.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
May 2014
The UV-vis absorption, steady state/time resolved fluorescence spectroscopy and synchronous fluorescence, circular dichroism (CD) spectroscopy are used to investigate the interaction mechanisms of dihydroartemisinin (DHA) and 9-hydroxy-dihydroartemisinin (9-OH DHA), respectively. The UV-vis studies present that DHA and 9-OH DHA can disturb the structure of bovine hemoglobin (BHb). Steady state/time resolved and synchronous fluorescence spectroscopy reveal that the binding constant of DHA with BHb is bigger than 9-OH DHA.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
April 2014
The interaction between prodigiosin (PG) and calf thymus DNA (ct-DNA) was investigated firstly by using UV-Visible (UV-Vis), fluorescence, Fourier transform infrared (FT-IR), circular dichroism (CD) spectroscopies and viscosity measurement in Tris-HCl buffer solution (pH 6.8). The experimental results indicated that PG intercalated into the DNA helix.
View Article and Find Full Text PDFSpectrochim Acta A Mol Biomol Spectrosc
October 2012
In this article, the interaction mechanism of prodigiosin (PG) with bovine hemoglobin (BHb) is studied in detail using various spectroscopic technologies. UV-vis absorption and fluorescence spectra demonstrate the interaction process. The Stern-Volmer plot and the time-resolved fluorescence study suggest the quenching mechanism of fluorescence of BHb by PG is a static quenching procedure, and the hydrophobic interactions play a major role in binding of PG to BHb.
View Article and Find Full Text PDFThe photoreduction of nitrobenzene (NB) on TiO(2) nanoparticles modified with asparagine (Asp), serine (Ser), phenylalanine (Phe) and tyrosine (Tyr), which were found to bind to TiO(2) via carboxyl group, have been investigated under high-pressure mercury irradiation. Modification of TiO(2) with Asp, Ser and Phe resulted in enhanced photocatalytic degradation rate of NB and high selective activity to aniline (AN) compared to using bare TiO(2). Furthermore, NB degradation followed a reductive approach over Asp, Ser, Phe-modified TiO(2) whether in additional of methanol or not.
View Article and Find Full Text PDF