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The contribution of water to DNA conformational change, DNA–protein interactions, and DNA–ligand recognition has been underlined. Here, we investigate the relaxation process of water around the Dickerson–Drew B-DNA duplex using terahertz spectroscopy. By controlling the DNA concentration, the relaxation time for water reorientation and the width of the DNA hydration layer are determined. We found that a layer of weakly bound hydration water, with a relaxation time of 11.6 ps, extends 7.6 Å from the tight-binding water layer. This result demonstrates that a shell of hydration water, with reorientation time on the order of tens of picoseconds, exists beyond the structurally integrated water usually observed around DNA. [ABSTRACT FROM AUTHOR]

We investigated the fabrication of heterojunction photodetectors consisting of nanostructured NiO and Si. The spin coating of colloidal Ni(OH) 2 and subsequent thermal annealing at 400 °C in air ambient led to the formation of NiO, in which a number of nanosheets (50–80 nm in size and 11–15 nm in height) were aggregated. The 263-nm-thick NiO showed an average optical transmittance of 83.7% in the wavelength range of 250–1500 nm and exhibited an energy bandgap of 3.69 eV. The nanostructured NiO/Si heterojunction photodetectors exhibited clear rectifying I-V behavior in the dark condition and showed prominent photovoltaic properties under illumination. Time-dependent photocurrent analysis showed that the photoresponsivity was 156.3 µA/W, 418 µA/W and 1.678 mA/W at the source wavelength of 385, 515, and 620 with optical power densities of 1.1, 0.69, and 0.22 mW/cm 2 , respectively. [ABSTRACT FROM AUTHOR]

Abstract: Amorphous In–Ga–Zn–O (a-IGZO) thin films (∼200nm thickness) were deposited by radio-frequency (RF) magnetron sputtering on silicon and glass substrates at various working pressures (0.67–2.67Pa) and a fixed oxygen-to-argon gas-flow ratio (O2/Ar=5%). The transparency of all of the films was more than 85% in the visible range. With increased working pressure, the surface morphology of the films, as observed under atomic force microscopy (AFM), became rough; the optical band gap, estimated by Tauc plot, increased, and the mobility and carrier concentrations, according to Hall measurement, decreased and increased, respectively. The resistivity of the films initially decreased (up to 2.00Pa working pressure) and then increased (at 2.67Pa). It is suggested that the electrical property changes were affected by the role of the oxygen vacancies, whether as effective donors or as scattering centers. [Copyright &y& Elsevier]