Slip casting and extruding shapes of rhenium with metal oxide additives. 1: Feasibility demonstration

The feasibility of fabricating small rhenium parts with metal oxide additives by means of slip casting and extrusion techniques is described. The metal oxides, ZrO2 and HfO2 were stabilized into the cubic phase with Y2O3. Additions of metal oxide to the rhenium of up to 15 weight percent were used. Tubes of 17 mm diameter with 0.5 mm walls were slip cast by adapting current ceramic oxide techniques. A complete cast double conical nozzle demonstrated the ability to meet shapes and tolerances. Extrusion of meter long tubing lengths of 3.9 mm o.d. x 2.3 mm i.d. final dimension is documented. Sintering schedules are presented to produce better than 95% of theoretical density parts. Finished machining was found possible were requried by electric discharge machining and diamond grinding

Research on the application of satellite remote sensing to local, state, regional, and national programs involved with resource management and environmental quality

Project summaries and project reports are presented in the area of satellite remote sensing as applied to local, regional, and national environmental programs. Projects reports include: (1) Douglas County applications program; (2) vegetation damage and heavy metal concentration in new lead belt; (3) evaluating reclamation of strip-mined land; (4) remote sensing applied to land use planning at Clinton Reservoir; and (5) detailed land use mapping in Kansas City, Kansas

Tunable-filter imaging of quasar fields at z ~ 1. II. The star-forming galaxy environments of radio-loud quasars

We have scanned the fields of six radio-loud quasars using the Taurus Tunable Filter to detect redshifted [OII] 3727 line-emitting galaxies at redshifts 0.8 < z < 1.3. Forty-seven new emission-line galaxy (ELG) candidates are found. This number corresponds to an average space density about 100 times that found locally and, at L([OII]) < 10^{42} erg s^{-1} cm^{-2}, is 2 - 5 times greater than the field ELG density at similar redshifts, implying that radio-loud quasars inhabit sites of above-average star formation activity. The implied star-formation rates are consistent with surveys of field galaxies at z ~ 1. However, the variation in candidate density between fields is large and indicative of a range of environments, from the field to rich clusters. The ELG candidates also cluster -- both spatially and in terms of velocity -- about the radio sources. In fields known to contain rich galaxy clusters, the ELGs lie at the edges and outside the concentrated cores of red, evolved galaxies, consistent with the morphology-density relation seen in low-redshift clusters. This work, combined with other studies, suggests that the ELG environments of powerful AGN look very much the same from moderate to high redshifts, i.e. 0.8 < z < 4.Comment: 18 pages, 18 figures, uses emulateapj.cls. Accepted for publication in A

Simple supersymmetric solution to the strong CP problem

It is shown that the minimal supersymmetric left-right model can provide a natural solution to the strong {\it CP} problem without the need for an axion, nor any additional symmetries beyond supersymmetry and parity.Comment: Plain Latex. 10 pages, including two figures which are part of the Latex file. Shortened version, to appear in Phys. Rev. Lett. 7

Can we improve the prediction of hip fracture by assessing bone structure using shape and appearance modelling?

Copyright 2013 Elsevier B.V., All rights reserved.Peer reviewedPreprin

Simulating Impacts of Extreme Weather Events on Urban Transport Infrastructure in the UK

Urban areas face many risks from future climate change and their infrastructure will be placed under more pressure due to changes in climate extremes. Using the Tyndall Centre Urban Integrated Assessment Framework, this paper describes a methodology used to assess the impacts of future climate extremes on transport infrastructure in London. Utilising high-resolution projections for future climate in the UK, alongside stochastic weather generators for downscaling, urban temperature and flooding models are used to provide information on the likelihood of future extremes. These are then coupled with spatial network models of urban transport infrastructure and, using thresholds to define the point at which systems cease to function normally, disruption to the networks can be simulated. Results are shown for both extreme heat and urban surface water flooding events and the impacts on the travelling population, in terms of both disruption time and monetary cost

Natural Gauge Hierarchy in SO(10)

It is shown that a natural gauge hierarchy and doublet-triplet splitting can be achieved in SO(10) using the Dimopoulos-Wilczek mechanism. Artificial cancellations (fine-tuning) and arbitrary forms of the superpotential are avoided, the superpotential being the most general compatible with a symmetry. It is shown by example that the Dimopoulos-Wilczek mechanism can be protected against the effects of higher-dimension operators possibly induced by Planck-scale physics. Natural implementation of the mechanism leads to an automatic Peccei-Quinn symmetry. The same local symmetries that would protect the gauge hierarchy against Planck-scale effects tend to protect the axion also. It is shown how realistic quark and lepton masses might arise in this framework. It is also argued that ``weak suppression'' of proton decay can be implemented more economically than can ``strong suppression'', offering some grounds to hope (in the context of SO(10)) that proton decay could be seen at Superkamiokande.Comment: 26 pages in plain LaTeX, 5 figures available on request, BA-94-0

Soil moisture detection by Skylab's microwave sensors

The author has identified the following significant results. Terrain microwave backscatter and emission response to soil moisture variations were investigated using Skylab's 13.9 GHz RADSCAT (radiometer/scatterometer) system. Data acquired on June 5, 1973, over a test site in west-central Texas indicated a fair degree of correlation with composite rainfall. The scan made was cross-track contiguous (CTC) with a pitch of 29.4 deg and no roll effect. Vertical polarization was employed with both radiometer and scatterometer. The composite rainfall was computed according to the flood prediction technique using rainfall data supplied by weather reporting stations

The lumbar spine has an intrinsic shape specific to each individual that remains a characteristic throughout flexion and extension

Peer reviewedPostprin

Role of oxygen in the electron-doped superconducting cuprates

We report on resistivity and Hall measurements in thin films of the electron-doped superconducting cuprate Pr$_{2-x}$Ce$_{x}$CuO$_{4\pm\delta}$. Comparisons between x = 0.17 samples subjected to either ion-irradiation or oxygenation demonstrate that changing the oxygen content has two separable effects: 1) a doping effect similar to that of cerium, and 2) a disorder effect. These results are consistent with prior speculations that apical oxygen removal is necessary to achieve superconductivity in this compound.Comment: 5 pages, 5 figure