A novel noncontacting waveguide backshort for millimeter and submillimeter wave frequencies

A new noncontacting waveguide backshort was developed for millimeter and submillimeter wave frequencies. It employs a metallic bar with rectangular or circular holes. The size and spacing of the holes are adjusted to provide a periodic variation of the guide impedance on the correct length scale to give a large reflection of RF frequency power. This design is mechanically rugged and can be easily fabricated for millimeter wave frequencies above 300 GHz where conventional backshorts are difficult to fabricate. Model experiments were performed at 4 to 6 GHz to optimize the design. Values of reflected power greater than 95 percent over a 30 percent bandwidth were achieved. The design was scaled to WR-10 band (75 to 110 GHz) with comparably good results

The M5 and M4 Edges of Gold in the Pure State and in a Gold Copper Alloy

For most of the M5 and M4 x-ray absorption edges already measured there is a discrepancy between observed and calculated values. The M1 edges occasionally have a small discrepancy while the M2 and M3 edges seldom show any. Siegbahn and Phelps have suggested that the final levels in the edge transitions are valence and low lattice levels and that the selection rule Δ1= ± 1 is usually giving the transition preference. A change in atomic spacing of a metal, such as often results from alloying it, should produce a change in the energies of its lattice levels. The gold M5 and M4 edges from gold and from a 50 atomic per cent copper gold alloy were photographed in a vacuum spectrometer. Significant shifts to higher energies in M5 of 2.5 electron volts and in M4 of 6.8 volts were found. These results show that the final levels in M absorption transitions are lattice levels, and they give credence to the assumption that there are preferred atomic to lattice level transitions

Alien Registration- Mcgrath, Louise W. (Houlton, Aroostook County)

https://digitalmaine.com/alien_docs/34791/thumbnail.jp

PILOT: design and capabilities

The proposed design for PILOT is a general-purpose, wide-field 1 degree 2.4m, f/10 Ritchey-Chretien telescope, with fast tip-tilt guiding, for use 0.5-25 microns. The design allows both wide-field and diffraction-limited use at these wavelengths. The expected overall image quality, including median seeing, is 0.28-0.3" FWHM from 0.8-2.4 microns. Point source sensitivities are estimated.Comment: 4 pages, Proceedings of 2nd ARENA conference 'The Astrophysical Science Cases at Dome C', Potsdam, 17-21 September 200

Providing Public Transport for Tourists in Rural Areas

Travel, both to the destination area and within the area, accounts for a high proportion of tourism’s emissions. Yet, relatively little attention has been directed at reducing emissions through encouraging visitors to use public rather private transport. This paper reports the findings of surveys of bus passengers within British rural tourist areas and demonstrates how they bring extra visitors and spending to attractions, while reducing car use. It discusses the potential of using public transport to enhance the tourism offer and the problems, and some solutions, of funding such services. Recent developments are introduced

Easily missed? Bladder cancer in women

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Evolution of topological order in Xe films on a quasicrystal surface

We report results of the first computer simulation studies of a physically adsorbed gas on a quasicrystalline surface, Xe on decagonal Al-Ni-Co. The grand canonical Monte Carlo method is employed, using a semi-empirical gas-surface interaction, based on conventional combining rules, and the usual Lennard-Jones Xe-Xe interaction. The resulting adsorption isotherms and calculated structures are consistent with the results of LEED experimental data. The evolution of the bulk film begins in the second layer, while the low coverage behavior is epitaxial. This transition from 5-fold to 6-fold ordering is temperature dependent, occurring earlier (at lower coverage) for the higher temperatures