Coupled Magnetic Excitations in Single Crystal PrBa2Cu3O6.2

The dispersion of the low-energy magnetic excitations of the Pr sublattice in PrBa2Cu3O6.2 is determined by inelastic neutron scattering measurements on a single crystal. The dispersion, which shows the effect of interactions with the Cu spin-waves, is well described by a model of the coupled Cu-Pr magnetic system. This enables values for the principal exchange constants to be determined, which suggest that both Pr-Pr and Cu-Pr interactions are important in producing the anomalously high ordering temperature of the Pr sublattice. Measurements of the Cu optic spin wave mode show that the inter-layer Cu-Cu exchange is significantly lower than in YBa2Cu3O6.2.Comment: To be published Phys. Rev. Let

Size-dependent oxygen-related electronic states in silicon nanocrystals

Silicon nanocrystals embedded in SiO2 were isolated with a selective etching procedure, and the isolated nanocrystals' excitonic emission energy was studied during controlled oxidation. Nanocrystals having initial diameters, d(0), of similar to 2.9-3.4 nm showed a photoluminescence (PL) blueshift upon oxidatively induced size reduction, as expected from models of quantum confinement. Oxidation of smaller Si nanocrystals (d(0)similar to 2.5-2.8 nm) also initially resulted in a PL blueshift, but a redshift in the PL was then observed after growth of similar to 0.3 monolayers of native oxide. This decrease in excitonic emission energy during oxidation is consistent with the theoretically predicted formation of an oxygen-related excitonic recombination state

Are Mock Jurors Influenced by the Defendants Gender, Socio-Economic Status and Emotional State in Forensic Medicine?

The aim of this study was to investigate whether mock jurors’ decisions were affected by the defendant’s gender, socio-economic status and emotional state in mock cases. The implications are far reaching, especially in trials that involve forensic medicine. An experimental design was used where a total of 24 participants from Bournemouth University took part, and were assigned to one of four groups. In these groups, the three independent variables were manipulated. Participants were presented with two murder/manslaughter cases. The results suggest male defendants received harsher judgements than female defendants. More female defendants were found not guilty than male defendants. Male defendants from a high socio-economic background received harsher judgements than male defendants from a low socio-economic background. Female defendants from a low socio-economic background received harsher judgements than female defendants from a high socio-economic background. Female defendants were found to be more trustworthy than male defendants. These findings are discussed are discussed in the context of the jury’s verdict, sentence length and personal opinion of the defendant

Quasiclassical calculation of spontaneous current in restricted geometries

Calculation of current and order parameter distribution in inhomogeneous superconductors is often based on a self-consistent solution of Eilenberger equations for quasiclassical Green's functions. Compared to the original Gorkov equations, the problem is much simplified due to the fact that the values of Green's functions at a given point are connected to the bulk ones at infinity (boundary values) by ``dragging'' along the classical trajectories of quasiparticles. In finite size systems, where classical trajectories undergo multiple reflections from surfaces and interfaces, the usefulness of the approach is no longer obvious, since there is no simple criterion to determine what boundary value a trajectory corresponds to, and whether it reaches infinity at all. Here, we demonstrate the modification of the approach based on the Schophol-Maki transformation, which provides the basis for stable numerical calculations in 2D. We apply it to two examples: generation of spontaneous currents and magnetic moments in isolated islands of d-wave superconductor with subdominant order-parameters s and d_{xy}, and in a grain boundary junction between two arbitrarily oriented d-wave superconductors. Both examples are relevant to the discussion of time-reversal symmetry breaking in unconventional superconductors, as well as for application in quantum computing.Comment: 6 pages, Submitted for publication in the proceedings of MS+S2002 conference, Japa

The performance of modified jatropha-based nanofluid during turning process

The industry's extensive use of petroleum-based metalworking fluid (MWF) harms the environment and humans. The production of bio-based MWF, especially from crude jatropha oil (CJO), has therefore taken numerous initiatives. This aimed to formulate newly modified jatropha oil (MJO) with the addition of 0.05wt.% hBN and 0.05wt.% MoS2 as the nanofluid for MWF. The performance of the nanofluids was determined through the turning process in terms of cutting temperature, workpiece surface roughness, tool life and tool wear of the tool lubricated by the nanofluids. The performance of the nanofluid samples was compared with the synthetic ester (SE). From the results, after conducted 100mm axial cutting length MJO+hBN+MoS2 recorded the lowest in cutting temperature and surface roughness compared to all samples. The result shows that MJO+hBN+MoS2 has longer tool life (6500mm) compared to SE (6000mm). Abrasion and adhesion were observed as the dominant tool wear mechanism. In conclusion, MJO+hBN+MoS2 shows better machining performance and has the potential to be an environmentally friendly metalworking fluid