Hydrogen peroxide is produced commercially by the sequential hydrogenation and oxidation of anthraquinone (AQ) and tetrahydroanthraquinone (THAQ). The hydrogenation of AQ and THAQ on the Pd(111) surface is investigated with periodic density functional theory (DFT) calculations in this work. Dihydrogen is preferentially adsorbed on the top of a Pd atom, and the produced hydrogen atoms are on two neighboring 3-fold hollow fcc positions. The three benzene rings of AQ are located at bridge sites on the Pd(111) surface. The two carbonyl oxygen atoms of AQ and THAQ successively abstract the surface hydrogen atoms to produce anthrahydroquinone (AHQ) and tetrahydroanthrahydroquinone (THAHQ), respectively. The formation of unwanted byproducts, anthrone (AN), tetrahydroanthrone (THAN), oxanthrone (OAN), and tetrahydro-oxanthrone (THOAN), in the hydrogenation step of the AQ process is also studied to consider the suppression of these byproducts.

Classical transport of particles and heat in field-reversed mirrors is discussed. The X-points (field nulls on axis) are shown to have no deleterious effect on transport; this conclusion is true for any transport model. For an elongated Hill's vortex equilibrium the classical diffusion coefficient is calculated analytically and used to construct an analytic solution to the transport equation for particles or energy; this yields exact results for particle and energy confinement times. These life-times are roughly 3 to 6 times shorter than previous heuristic estimates. Experimentally determined life-times are within a factor of 3 to 4 of our estimates. To assess the impact of these results on reactor designs, the authors construct an analytic reactor model in which neutral-beam input balances ion heat loss. Energy loss due to synchrotron radiation is calculated analytically and shown to be negligible, even with no wall reflection. Formulas are presented which give the reactor parameters in terms of plasma temperature, energy multiplication factor Q, and allowed neutron wall loading. The effect of anomalous resistivity is incorporated heuristically by assuming an anomalous resistivity which is enhanced by a factor A over classical resistivity. For large A the minimum power of a reactor scales as A 11 / 6 . A = 50 gives a reactor design which still seems reasonable, but A = 200 leads to extremely large, high-power reactors.

Room temperature continuous wave operation of ZnSe-based blue/green laser diodes grown homoepitaxially on conductive ZnSe substrates with threshold current densities as low as 176 A/cm2 has been demonstrated. This is the lowest reported threshold among all short wavelength lasers in the blue/green region. Lifetimes at room temperature of up to 2.1 h have been obtained for lasers with pre-existing defect densities lower than 3×104 cm−2.

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Zirconia films stabilized by Y2O3 were deposited by metal-organic chemical vapor techniques onto various crystalline substrates. Y2O3, ZrO2 and mixtures of these two were deposited and characterized. The deposition rate, the film composition and the structure could be systematically varied through the Y(C11H19O2)3, Zr(O·t-C4H9)4 and O2 source gas ratios and the substrate temperature. The Y/Zr ratio could be adjusted by controlling the ratio in Y(C11H19O2)3 to Zr(O·t-C4H9)4 partial pressures. However, the Y/Zr ratio was found to be smaller than that estimated based on the deposition rates of unmixed Y2O3 and ZrO2 films. The activation energy of the Y2O3 component in YSZ film growth was similar to that of the ZrO2 component in YSZ films. These YSZ values were more than 4 times larger than those of unmixed Y2O3 or ZrO2 films.