We report Mn-doped GaN nanowires exhibiting ferromagnetism even at room temperature. The growth of single-crystalline wurtzite-structured GaN nanowires doped homogeneously with about 5 at. % Mn was achieved by chemical vapor deposition using the reaction of Ga∕GaN∕MnCl2 with NH3. The ferromagnetic hysteresis at 5 and 300 K and the temperature-dependent magnetization curves suggest the Curie temperature around 300 K. Negative magnetoresistance of individual nanowires was observed at the temperatures below 150 K.

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Cd1-xMnxS (x = 0.1-0.3) nanowires were synthesized by using the chemical vapor deposition method. They all consist of a single-crystalline wurtzite CdS structure with a [010] or [011] growth direction. The X-ray diffraction pattern reveals the contraction of the lattice constants due to the incorporation of Mn. The Mn2+ emission at approximately 2.15 eV, originating from the d-d (4T1 --> 6A1) transition, appears below 50-80 K. Its decay time is in the range of 0.55-1 ms, showing a decrease with increasing Mn content. The Mn doping reduces significantly the decay time of band-edge emission from 590 ps to 20-30 ps. Upon applying magnetic field (up to 7 T), the Mn2+ emission is suppressed and donor-acceptor pair emission becomes dominant, suggesting the energy transfer from the band electrons to the Mn2+ ions.

The major objective of this study is to estimate Korean food shoppers' willingness to pay (WTP) for imported beef with traceability. We use an experimental elicitation method, the random nth price auction, to identify consumers' valuation for traceable imported beef. We also analyse the effect of different types of information on these valuations. Results indicate that consumers are generally willing to pay a 39 per cent premium for the traceable imported beef over similar beef without traceability. Results also suggest that in contrast to the insignificant effect of positive information, negative and two-sided information about traceability significantly reduces WTP.

Mixture of single-crystalline MnO and Mn3O4 nanowires was synthesized by thermal evaporation of MnCl2 powders. The diameter is 50–100nm, the length is about 20μm, and the growth direction is uniformly [100] for both cubic MnO and tetragonal Mn3O4 nanowires. The temperature-dependent magnetization and magnetic hysteresis curves suggest the Curie temperature of 12 and 43K for the MnO and Mn3O4 nanowires, respectively.