Highly transparent conductive Ga-doped zinc oxide (ZnO:Ga) has been deposited on 3 in.×4 in. Corning 7059 glass and other substrates using a high speed rotating disk reactor low pressure metal organic chemical vapor deposition system. Diethylzinc, oxygen, and triethylgallium were used as precursors. The films exhibit low resistivity, ∼2.6×10−4 Ω cm, high optical transparency (>85%) in the visible range, good adhesion, and are highly stable. The film properties were correlated with the growth conditions, including flow rate, temperature, pressure, and doping concentrations. The microstructural properties of the films, such as surface and interface morphology, crystallinity, and composition were studied using scanning electron microscopy, x-ray diffraction, and secondary ion mass spectroscopy. The resistivity and transmittance of the films were investigated by four-point probe measurements, photoluminescence spectroscopy, and optical absorption spectroscopy. In order to meet the needs for application to flat panel displays, the thermal stability of the Ga-doped ZnO films have been tested by a dc biased heater. The feasibility of film processing was also investigated through patterning and wet chemical etching.

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There are two key requirements for reliably simulating enzyme reactions: one is a reasonably accurate potential energy surface to describe the bond forming/breaking process as well as to adequately model the heterogeneous enzyme environment; the other is to perform extensive sampling since an enzyme system consists of at least thousands of atoms and its energy landscape is very complex. One attractive approach to meet both daunting tasks is Born-Oppenheimer ab initio QM/MM molecular dynamics simulation (aiQM/MM-MD) with umbrella sampling. In this chapter, we describe our recently developed pseudobond Q-Chem–Amber interface, which employs a combined electrostatic-mechanical embedding scheme with periodic boundary condition and the particle mesh Ewald method for long-range electrostatics interactions. In our implementation, Q-Chem and the sander module of Amber are combined at the source code level without using system calls, and all necessary data communications between QM and MM calculations are achieved via computer memory. We demonstrate the applicability of this pseudobond Q-Chem–Amber interface by presenting two examples, one reaction in aqueous solution and one enzyme reaction. Finally, we describe our established aiQM/MM-MD enzyme simulation protocol, which has been successfully applied to study more than a dozen enzymes.

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The influence of sintering temperature on the critical transition temperature T c and critical current density J c for the MgB 2 superconductor was investigated systematically with the observation of Raman scattering measurement and flux pinning force F p analysis. The enhanced E 2g mode in Raman spectra with increasing in situ sintering temperature shows gradual strengthening of the electron-phonon coupling in MgB 2 , which means that the crystals become more harmonic after higher temperature sintering. However, the crystal harmonicity is degraded for samples sintered at even higher temperature due to Mg deficiency. A possible explanation for the J c ͑H͒ performance, which is in accordance with the Raman spectroscopy observation and F p analysis, is the cooperation between the electron-phonon coupling in the E 2g mode and the flux pinning centers, mainly originating from the lattice distortion due to the different sintering temperatures.