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The electron-impact excitations from the ground state to the excited levels and as well as the subsequent radiative decays of neonlike Fe16+ ions have been investigated within the framework of the multiconfigurational Dirac–Fock method and the relativistic distorted-wave theory. Special attention has been paid to emission behaviors of the astrophysically relevant resonance 3C and intercombination 3D lines emitted in the radiative decays of Fe16+ ions. To this end, we calculate the angular distribution and linear polarization of both of the lines for a series of impact electron energies. It is found that the angular and polarization behaviors of the resonance 3C line are nearly the same as those of the intercombination 3D line. Nevertheless, the angular and polarization behaviors of both of the lines are found to be very sensitive to the impact electron energy, especially at low impact energies. Based on such a sensitivity, it is expected that high-precision angular and polarization measurements of the 3C and 3D lines could be served as a tool for revealing detailed information such as electron energy of relevant laboratory and astrophysical plasmas. [ABSTRACT FROM AUTHOR]

A previously developed theory for the temperature-dependent resonance Raman scattering is used to study the surface-enhanced Raman scattering. Two models, the displaced oscillator model and the displaced-distorted oscillator model, based on the harmonic potential energy surfaces are carried out to calculate the surface-enhanced Raman scattering excitation profiles of the pyridine molecule adsorbed on a silver electrode, for which the density functional theory method is applied to evaluate the potential energy surfaces of the adsorption structure. In this framework, the distortion effect on the surface-enhanced Raman scattering will be discussed by comparing both models. The overlapping resonance of multiexcited electronic transitions is also studied, in which the interference between electronic transitions has been taken into account. It will be used to study the abnormal band at 1005.6 cm-1 with the exciting radiation 457.9 nm. [ABSTRACT FROM AUTHOR]

Fluorinated diamond-like carbon (DLC) films have good biocompatibility and bloodcompatibility. When they are used in cardiac valve prosthesis, the wear resistance has to be investigated in more detail. In this paper, the tribological behavior of fluorinated DLC films under different loads and sliding speeds in bull serum albumin (BSA) solutions were investigated by ball-on-disc friction tests. The results show that the proteins in BSA solutions promoted the DLC film adhesion failure because of the increased friction coefficients and accelerated corrosion rate. The fluorine doping can lower the corrosion rate of DLC film, thereby improving the adhesion stability and wear resistance of DLC in BSA solutions. [ABSTRACT FROM AUTHOR]

Summary The formation of mycorrhiza on Pinus tabulaeformis (Pt) seedlings by ectomycorrhizal fungi (ECMF), the protective effect of the ECMF on damping-off caused by Rhizoctonia solani and the expression of pathogenesis-related proteins (PR-proteins) induced by Amanita vaginata and/or R. solani in Pt seedlings were investigated. The results indicated that: (i) among the 10 ECMF tested, five species ( Gomphidius viscidus, Suillus laricinus, Suillus tomentosus, A. vaginata and Basidiomycetes no. 058) formed mycorrhiza with Pt seedlings. There was a positive correlation between mycorrhizal colonization levels and protective effects ( r = 0.9207). Among the five species, A. vaginata had the highest colonization level and the best protective effect against damping-off; however, G. viscidus had no protective effect even though it had a high mycorrhization level. (ii) Chitinases, β-1,3-glucanases and PR-proteins in the seedlings were not induced by A. vaginata colonization, but were induced when A. vaginata-mycorrhizal seedlings were attacked by R. solani. It is possible that chitinases, β-1,3-glucanases and 108, 97, 78, 44, 37 and 14-kDa PR-proteins induced both by A. vaginata and R. solani protect Pt seedlings from R. solani infection. [ABSTRACT FROM AUTHOR]

The effects of co-doped CuO and B2O3 addition on the sintering temperature, microstructure and microwave dielectric properties of MgNb2O6 ceramics prepared with conventional solid-state route were investigated. When both CuO and B2O3 were added, the MgNb2O6 ceramics were not only sintered at 1000 °C but also improved the Qf value. MgNb2O6 ceramics can be well sintered to approach to 98.1% theoretical density with 2.0 wt.% CuO–B2O3 additive due to its liquid phase effect. With 2.0 wt.% CuO–B2O3, a dielectric constant of 21.5, a Qf value of 108,000(GHz) and a τ f value of −44 ppm/°C of MgNb2O6 ceramics doped with CuO–B2O3 sintered at 1050 °C for 2 h are obtained. The variation of εr, Qf and τ f were also explained based on the difference in microstructures. [ABSTRACT FROM AUTHOR]