Spin-polarized states of nuclear matter

The equations of state of spin-polarized nuclear matter and pure neutron matter are studied in the framework of the Brueckner-Hartree-Fock theory including a three-body force. The energy per nucleon $E_A(\delta)$ calculated in the full range of spin polarization ${\delta} = \frac{\rho_{\uparrow}-\rho_{\downarrow}}{\rho}$ for symmetric nuclear matter and pure neutron matter fulfills a parabolic law. In both cases the spin-symmetry energy is calculated as a function of the baryonic density along with the related quantities such as the magnetic susceptibility and the Landau parameter $G_0$. The main effect of the three-body force is to strongly reduce the degenerate Fermi gas magnetic susceptibility even more than the value with only two body force. The EOS is monotonically increasing with the density for all spin-aligned configurations studied here so that no any signature is found for a spontaneous transition to a ferromagnetic state.Comment: Contribution to GISELDA Meeting, 14-18 January, 2002 (Frascati), to appear in World Scientific (Singapore

Rectifying "nanohomo" contacts of W-Ga-C composite pad and nanowire fabricated by focused-ion-beam induced chemical vapour deposition

We prepared W-Ga-C composite contacts on W-Ga-C composite nanowires by focused-ion-beam-induced chemical vapor deposition using a dual-beam scanning electron microscope/focused-ion-beam system. The current-voltage (I-V) characteristics of wires were found to change from nonlinear to linear with increasing wire thickness. For wires with small dimensions, which result in strong nonlinear I-V behavior at room temperature, pairs of contacts were fabricated along the wire under different ion energies and scanning modes. Nonlinear and asymmetric rectifying I-V characteristics were observed. The results suggest that nanoscaled W-Ga-C nanowires may behave similarly to semiconductors and that the contact characteristics may be modified using different deposition conditions. Furthermore, ohmiclike junctions could be formed through the use of specific deposition conditions for the contact pads and nanowires

Suppression of local haze variations in MERIS images over turbid coastal waters for retrieval of suspended sediment concentration

Atmospheric correction over turbid waters can be problematic if atmospheric haze is spatially variable. In this case the retrieval of water quality is hampered by the fact that haze variations could be partly mistaken for variations in suspended sediment concentration (SSC). In this study we propose the suppression of local haze variations while leaving sediment variations intact. This is accomplished by a multispectral data projection (MDP) method based on a linear spectral mixing model, and applied prior to the actual standard atmospheric correction. In this linear model, the hazesediment spectral mixing was simulated by a coupled water-atmosphere radiative transfer (RT) model. As a result, local haze variations were largely suppressed and transformed into an approximately homogenous atmosphere over the MERIS top-of-atmosphere (TOA) radiance scene. The suppression of local haze variations increases the number of satellite images that are still suitable for standard atmospheric correction processing and subsequent water quality analysi

Optimization of Dimples in Microchannel Heat Sink with Impinging Jets—Part B: the Influences of Dimple Height and Arrangement

The combination of a microchannel heat sink with impinging jets and dimples (MHSIJD) can effectively improve the flow and heat transfer performance on the cooling surface of electronic devices with very high heat fluxes. Based on the previous work by analysing the effect of dimple radius on the overall performance of MHSIJD, the effects of dimple height and arrangement were numerically analysed. The velocity distribution, pressure drop, and thermal performance of MHSIJD under various dimple heights and arrangements were presented. The results showed that: MHSIJD with higher dimples had better overall performance with dimple radius being fixed; creating a mismatch between the impinging hole and dimple can solve the issue caused by the drift phenomenon; the mismatch between the impinging hole and dimple did not exhibit better overall performance than a well-matched design