Angular distribution of photoelectrons at 584A using polarized radiation

Photoelectron angular distributions for Ar, Xe, N2, O2, CO, CO2, and NH3 were obtained at 584 A by observing the photoelectrons at a fixed angle and simply rotating the plane of polarization of a highly polarized photon source. The radiation from a helium dc glow discharge source was polarized (84%) using a reflection type polarizer

Modelling the spread of Wolbachia in spatially heterogeneous environments

The endosymbiont Wolbachia infects a large number of insect species and is capable of rapid spread when introduced into a novel host population. The bacteria spread by manipulating their hosts' reproduction, and their dynamics are influenced by the demographic structure of the host population and patterns of contact between individuals. Reaction–diffusion models of the spatial spread of Wolbachia provide a simple analytical description of their spatial dynamics but do not account for significant details of host population dynamics. We develop a metapopulation model describing the spatial dynamics of Wolbachia in an age-structured host insect population regulated by juvenile density-dependent competition. The model produces similar dynamics to the reaction–diffusion model in the limiting case where the host's habitat quality is spatially homogeneous and Wolbachia has a small effect on host fitness. When habitat quality varies spatially, Wolbachia spread is usually much slower, and the conditions necessary for local invasion are strongly affected by immigration of insects from surrounding regions. Spread is most difficult when variation in habitat quality is spatially correlated. The results show that spatial variation in the density-dependent competition experienced by juvenile host insects can strongly affect the spread of Wolbachia infections, which is important to the use of Wolbachia to control insect vectors of human disease and other pests

Strength and Behavior of Flare-bevel and Flare-vee Welded Connections in G450 Sheet Steel

G450 steel to AS 1397 is a cold-reduced sheet steel with in-line galvanizing. Its grade is 65 ksi (450 MPa) yield and 70 ksi (480 MPa) tensile strength. It is widely used in Australia for purlins, and is being used to fabricate light-weight portal frames, often by welding. The effect of welding on G450 sheet steel in the heat affected zone (HAZ) was unknown and so the project was performed to investigate the strength of flare-bevel and flare-vee welded connections. Flare-bevel and flare-vee welded connections in 0.06-in (1.5-mm) and 0.12-in (3.0-mm) sheet steels were tested to failure. The failure modes and ductility of different types of connections are described. The test results are used to check the design rules in the AISI Specification (Section E2.5) and the Australian/New Zealand Standard for Cold-Formed Steel Structures AS/NZS 4600 (Clause 5.2.6). Connections in 0.12-in (3.0-mm) sheet steel failed in the weld and it is important that these connections are checked for weld throat failure, not just parent material failure. The quality of flare-bevel welded connections in thin sheet steels produced by industry fabricators is investigated. The results of this study have recently been incorporated into the AISI Specification for Cold-Formed Steel Structures by reducing the thickness at which weld throat failure should be checked to 2.5 mm (0.10 in)

Strength and Behavior of Fillet Welded Connections in G450 Sheet Steel

G450 steel to AS 1397 is a cold-reduced sheet steel with in-line galvanizing. Its grade is 65 ksi (450 MPa) yield and 70 ksi (480 MPa) tensile strength. It is widely used in Australia for purlins, and is being used to fabricate light-weight Portal frames, often by welding. The effect of welding on G450 sheet steel in the heat affected zone was unknown and so the project was performed to investigate the strength of fillet welded connections. Transverse and longitudinal fillet welded connections in 0.06 in (1.5 mm) and 0.12 in (3.0 mm) sheet steels were tested to failure. The failure modes and ductility of different types of connections are described. The test results are used to check the design rules in the AISI Specification (Section E2.4) and the Australian/New Zealand Standard for Cold-Formed Steel Structures AS/NZS 4600 (Clause 5.2.3). Recommendations are made for revised capacity factors. The quality of fillet welded connections in thin sheet steels produced by industry fabricators is investigated. The need to complement the macro test with the destructive prying test as part of the pre-qualification procedure for such connections is demonstrated

Origin of Middle-Infrared Peaks in Cerium Compounds

We have demonstrated that the middle-infrared (mid-IR) peaks in the optical conductivity spectra of Ce$X_3$ ($X$ = Pd, Sn, In) can be explained by first-principle band structure calculation with the spin-orbit interaction. The mid-IR peak shapes in these materials are not identical to one another: CePd$_3$, CeSn$_3$, and CeIn$_3$ have a triple-peak structure, double-peak structure and broad single-peak structure, respectively. These peaks can be theoretically explained by the optical transition from the occupied state to the spin-orbit splitted Ce $4f$ state. This result indicates that the mid-IR peaks originate from the simple band picture with the Ce $4f$ state near the Fermi level, not from the conventional cf hybridization gap based on the periodic Anderson model.Comment: 5 pages, 6 figures. To be published in J. Phys. Soc. Jpn. 78(1) (2009

Spatial Buckling Behavior of High-rise Rack Frames

The paper investigates the global elastic buckling behavior of a high-rise adjustable pallet rack frame composed of thin-walled open sections. It is concluded that the simple element used in many commercial programs for 3D frame analysis is not sufficiently refined for accurate linear buckling analyses of high-rise rack frames

Elliptic Phases: A Study of the Nonlinear Elasticity of Twist-Grain Boundaries

We develop an explicit and tractable representation of a twist-grain-boundary phase of a smectic A liquid crystal. This allows us to calculate the interaction energy between grain boundaries and the relative contributions from the bending and compression deformations. We discuss the special stability of the 90 degree grain boundaries and discuss the relation of this structure to the Schwarz D surface.Comment: 4 pages, 2 figure

Elliptic aspects of statistical mechanics on spheres

Our earlier results on the temperature inversion properties and the ellipticisation of the finite temperature internal energy on odd spheres are extended to orbifold factors of odd spheres and then to other thermodynamic quantities, in particular to the specific heat. The behaviour under modular transformations is facilitated by the introduction of a modular covariant derivative and it is shown that the specific heat on any odd sphere can be expressed in terms of just three functions. It is also shown that the free energy on the circle can be written elliptically.Comment: 22 pages. JyTe