Two-dimensional photonic band-gap structures as quasi-metals

By considering waves that propagate out of the transverse plane, we show that common high index materials (eg GaAs) with a 2D array of air holes can act in some ways like a 3D photonic band-gap structure. In particular, we describe a dielectric "quasi-metal" that reflects all propagating light incident from free space

The impedance of a coil placed on a conducting plane

"Reprinted from AIEE Winter General Meeting, New York, N. Y. January 28 - February 2, 1962.""February 6, 1963.""Probe coils are useful in determining the properties of metals on which the coil is placed. An analysis and an equivalent circuit of the coil on a metal surface are needed and are presented here. The coil was assumed to have a ferromagnetic core, and the constants of the equivalent circuit were computed from the analysis. Experimental measurements of a probe coil on a metal surface, and with varying frequency and conductivity, were made to verify the theory."--Page 1

Natural resources of the Barron River catchment 1: stream habitat, fisheries resources and biological indicators

The Barron River drains into the Coral Sea, near Cairns, Queensland (Australia) and in comparison to other Queensland wet tropics streams, it has a relatively large catchment area of about 219,000 ha. The catchment has high fish diversity, with at least 209 estuarine and freshwater species and the Barron River Estuary is a spawning and nursery ground for a variety of fish and prawn species and supports a wide range of commercial and recreational fish species. The variance and abundance of benthic macroinvertebrates can provide valuable information on the ecological condition of a river system. Overall, the macroinvertebrate populations indicated a relatively healthy system although nutrient enrichment may be causing degradation. Reserves such as existing Fish Habitat Areas and a proposed marine park will provide ongoing protection for coastal wetlands. A series of potential management issues for the catchment and future monitoring strategies are discussed

The Empirical Mass-Luminosity Relation for Low Mass Stars

This work is devoted to improving empirical mass-luminosity relations and mass-metallicity-luminosity relation for low mass stars. For these stars, observational data in the mass-luminosity plane or the mass-metallicity-luminosity space subject to non-negligible errors in all coordinates with different dimensions. Thus a reasonable weight assigning scheme is needed for obtaining more reliable results. Such a scheme is developed, with which each data point can have its own due contribution. Previous studies have shown that there exists a plateau feature in the mass-luminosity relation. Taking into account the constraints from the observational luminosity function, we find by fitting the observational data using our weight assigning scheme that the plateau spans from 0.28 to 0.50 solar mass. Three-piecewise continuous improved mass-luminosity relations in K, J, H and V bands, respectively, are obtained. The visual mass-metallicity-luminosity relation is also improved based on our K band mass-luminosity relation and the available observational metallicity data.Comment: 8 pages, 2 figures. Accepted for publication in Astrophysics & Space Scienc