An investigation of the thermal shock resistance of lunar regolith and the recovery of hydrogen from lunar soil heated using microwave radiation

The objective is to develop a better understanding of the thermal shock properties of lunar regolith sintered using 2.45 GHz electromagnetic radiation and to do a preliminary study into the recovery of bound hydrogen in lunar soil heated using 2.45 GHz radiation. During the first phase of this work, lunar simulant material was used to test whether or not microhardness data could be used to infer thermal shock resistance and later actual lunar regolith was used. Results are included on the lunar regolith since this is of primary concern and not the simulant results. They were similar, however. The second phase investigated the recovery of hydrogen from lunar regolith and results indicate that microwave heating of lunar regolith may be a good method for recovery of bound gases in the regolith

An investigation of some mechanical and thermal properties of lunar simulant materials heated at 2.45 GHz

Lunar simulant material was fabricated to simulate Apollo 11, Apollo 15, and Apollo 16 soils. The approximate compositions which these soils simulate are given. Samples of each soil simulate were fabricated into right circular cylinders, placed into a microwave reaction cavity, and heated using 2.45 GHz radiation to a particular processing temperature at which it was held for a prescribed length of time. Examples are given of two microwave heating programs for these simulant samples. Upon completion of thermal processing, each sample had its top and bottom surfaces polished. A technique was employed which looks at hardness data to determine the fracture toughness of a material and then relates this to thermal shock resistance. Some advantages of this technique are its low cost for analysis and thermal shock resistance as a function of initial sample orientation in the microwave field can be determined. Samples were prepared for testing and results are expected. At the same time, other samples are currently being investigated using scanning electron microscopy to determine their microstructures

Investigation of mechanical and thermal properties of microwave-sintered lunar simulant materials using 2.45 GHz radiation

The mechanical and thermal properties of lunar simulant material were investigated. An alternative method of examining thermal shock in microwave-sintered lunar samples was researched. A computer code was developed that models how the fracture toughness of a thermally shocked lunar simulant sample is related to the sample hardness as measured by a micro-hardness indentor apparatus. This technique enables much data to be gathered from a few samples. Several samples were sintered at different temperatures and for different times at the temperatures. The melting and recrystallization characteristics of a well-studied binary system were also investigated to see if the thermodynamic barrier for the nucleation of a crystalline phase may be affected by the presence of a microwave field. The system chosen was the albite (sodium alumino silicate) anorthite system (calcium alumino silicate). The results of these investigations are presented

Microwave heating of lunar materials. Appendix A

Microwave heating of nonmetallic inorganic material has been of interest for many years. Von Hippel in the late 1940's and early 1950's investigated how microwave radiation up to 10 GHz couples to various insulator materials. Perhaps the most work has been done by Wayne Tinga at the University of Edmonton. Most of the work to date has been done at the two frequency bands allowed in industrial use (0.915 GHz and 2.45 GHz). However some work has recently been carried out at 28 GHz and 60 GHz. Work done in this area at Los Alamos National Laboratory is discussed

Robinson v. Shell Oil Co.: Policy-Not Ambiguity-Drives the Supreme Court\u27s Decision to Broaden Title VII\u27s Retaliation Coverage

Before the Supreme Court\u27s pronouncement in Robinson v. Shell Oil Co., a majority of the circuit courts were blurring seemingly unambiguous language to expand Title VII\u27s coverage to comport with amiable policy goals. Only policy justifications could explain the courts\u27 willingness to cover postemployment retaliation based on language that prohibits an employer from discriminating against his employees and that further defines employees as those persons employed by an employer. Clearly, the plain meaning of such language envisions that persons protected under Title VII have an existing employment relationship with the covered employer at the time of the alleged retaliatory conduct. Yet, nearly all circuit courts addressing the issue before Robinson found the policy arguments more compelling. In Robinson, the Supreme Court also found that the amiable policy goals of extended coverage weighed more heavily than the plain language of Title VII\u27s anti-retaliation provision

Strengthening Indigenous Social Work in the Academy

This paper provides an account of the development of an Indigenous Social Work program in Sudbury, Ontario and how it was conceived, developed and implemented. It describes the transformational approaches that Aboriginal faculty, communities and academic allies engaged in to create a rightful space for Indigenous social work in mainstream academia. In its 25th year, this program has provided many transformational opportunities for students, faculty and Aboriginal communities. Incorporating resistance and proactive momentum, the program has become pivotal in expanding the visibility and legitimacy for Indigenous social work in practice, theory, research and pedagogies. This program is an example of how community-faculty collaborations can sustain a robust Indigenous social work program

SUGGESTIONS FOR PRESENTING KRIGING RESULTS

Kriging maps are often part of the reported analyses in many environmental research studies including those our agency is working on in the area of precision/sustainable farming. All to often important details on the underlying variography and/or kriging procedures are omitted. Likewise the content and form of presenting kriging results vary greatly. Often features of the underlying variability are not readily seen. Instead of reviewing poor practice in current literature, we offer guidelines for reporting the methodology and presenting the results with the use of soil test phosphorus (STP) measures from a real world pasture study. Relevantly, the stationarity assumption for the variogram is argued; computational aspects for both the model and empirical variogram development are reported; and similarly, computational aspects for the kriging surface are reported. In short, enough detail is reported to understand and reproduce the analyses. Standard practice for presenting kriging results should include both the kriging estimates and the associated standard error map. Various planar and three dimensional plots are shown and discussed. Emphasis is on developing quality gray-scale planar maps for conventional publications. Ideally, for both recommended plots, patterns and unique features of the surfaces\u27 variability are revealed

Spatial and Temporal Stability of Airglow Measured in the Meinel Band Window at 1191.3 nm

We report on the temporal and spatial fluctuations in the atmospheric brightness in the narrow band between Meinel emission lines at 1191.3 nm using an R=320 near-infrared instrument. We present the instrument design and implementation, followed by a detailed analysis of data taken over the course of a night from Table Mountain Observatory. The absolute sky brightness at this wavelength is found to be 5330 +/- 30 nW m^-2 sr^-1, consistent with previous measurements of the inter-band airglow at these wavelengths. This amplitude is larger than simple models of the continuum component of the airglow emission at these wavelengths, confirming that an extra emissive or scattering component is required to explain the observations. We perform a detailed investigation of the noise properties of the data and find no evidence for a noise component associated with temporal instability in the inter-line continuum. This result demonstrates that in several hours of ~100s integrations the noise performance of the instrument does not appear to significantly degrade from expectations, giving a proof of concept that near-IR line intensity mapping may be feasible from ground-based sites.Comment: 15 figures, submitted to PAS

Three dimensional optical imaging of blood volume and oxygenation in the neonatal brain

Optical methods provide a means of monitoring cerebral oxygenation in newborn infants at risk of brain injury. A 32-channel optical imaging system has been developed with the aim of reconstructing three-dimensional images of regional blood volume and oxygenation. Full image data sets were acquired from 14 out of 24 infants studied; successful images have been reconstructed in 8 of these infants. Regional variations in cerebral blood volume and tissue oxygen saturation are present in healthy preterm infants. In an infant with a large unilateral intraventricular haemorrhage, a corresponding region of low oxygen saturation was detected. These results suggest that optical tomography may provide an appropriate technique for investigating regional cerebral haemodynamics and oxygenation at the cotside. (c) 2006 Elsevier Inc. All rights reserved

Islands of the Western Pacific

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