Lightweight solar concentrator structures, phase 2

This report summarizes the results of the program conducted by Ultramet under SBIR Phase 2 Contract NAS3-25418. The objective of this program was to develop lightweight materials and processes for advanced high accuracy Space Solar Concentrators using rigidized foam for the substrate structure with an integral optical surface

The Design, Fabrication, and Evaluation of a Low-Speed, Low-Turbulence, Anechoic Wind Tunnel

In order to provide a means for testing noise reduction techniques in propellers and fans, a low-speed, low-turbulence, anechoic wind tunnel was designed, fabricated and evaluated at Embry-Riddle Aeronautical University. This open circuit wind tunnel was designed using several other existing wind tunnels as a guide and incorporated an open jet test section. The tunnel, which was built almost entirely out of wood and fiberglass, is powered by a 15 hp centrifugal fan. Tufts of yarn, a pitot-static tube, and a hot film anemoter were used to determine the flow characteristics in the test section of this wind tunnel. From the hot film anemometer, values of velocity, standard deviation and turbulence intensity were determined for three different velocity settings; approximately 114 ft/s, 145 ft/s, and 215 ft/s respectively. For the 215 ft/s and 114 ft/s tests, the turbulence intensity ranged from 0.42% to 0.87% within a seven inch diameter about the centerline. This seven inch diameter was mapped out to simulate a seven inch diameter propeller. For the 145 ft/s test, the turbulence intensity became more erratic, and ranged between 0.67% and 1.5%. The velocity across the test section for all three tests varied by less than 2.0%, with 90% of the points varying by less than 1.0%

The Art / Crime Archive: An Anti-Boredom Space

This paper reports on an ongoing web-based project devoted to the study of deviant art and creative crime called the Art / Crime Archive: www.artcrimearchive.org. The Art / Crime Archive (ACA) is a collaborative laboratory, teaching center, and web-based platform devoted to the study of this space. The ACA is organized by an artist, a criminologist, and a computer engineer. The working process of the ACA involves locating, archiving, and discussing visual, audio, and text artifacts that support this shadow space. The work product is a dynamic archive which can be configured for a multiplicity of contexts—art exhibitions, academic presentations, community awareness panels, etc. The ACA’s objective is to foment a dynamic, dialectical, and innovative discussion of deviant art and creative crime

A major advance in powder metallurgy

Ultramet has developed a process which promises to significantly increase the mechanical properties of powder metallurgy (PM) parts. Current PM technology uses mixed powders of various constituents prior to compaction. The homogeneity and flaw distribution in PM parts depends on the uniformity of mixing and the maintenance of uniformity during compaction. Conventional PM fabrication processes typically result in non-uniform distribution of the matrix, flaw generation due to particle-particle contact when one of the constituents is a brittle material, and grain growth caused by high temperature, long duration compaction processes. Additionally, a significant amount of matrix material is usually necessary to fill voids and create 100 percent dense parts. In Ultramet's process, each individual particle is coated with the matrix material, and compaction is performed by solid state processing. In this program, Ultramet coated 12-micron tungsten particles with approximately 5 wt percent nickel/iron. After compaction, flexure strengths were measured 50 percent higher than those achieved in conventional liquid phase sintered parts (10 wt percent Ni/Fe). Further results and other material combinations are discussed

On the Influence of Ionic Strength on Radium and Strontium Sorption to Sandy Loam Soils

Models which can estimate environmental transport of radioactive contaminants in natural and engineered systems are required to 1) deploy effective remediation strategies for contaminated sites, 2) design waste repositories for future waste streams, and 3) ensure protection of human and environmental health in all cases. These models require accurate transport parameters in order to correctly predict how these contaminants will move in the subsurface. This work aimed to determine more accurately the distribution coefficients for radium and strontium sorption to Savannah River Site (SRS) soils. Radium and strontium sorption to the soils was found to be highly dependent upon ionic strength due to competition for ion exchange sites. Radium distribution coefficients (Kd) for the clayey soil were determined to be 185.1 ± 25.63 L kg-1 and 30.35 ± 0.66 L kg-1 for ionic strengths of 0.02M and 0.1M as NaCl which is the approximate ionic strength of groundwater at the SRS. Radium distribution coefficients for the sandy soil were determined to be 24.95 ± 2.97 L kg-1 and 9.05 ± 0.36 L kg-1 for ionic strengths of 0.02M and 0.1M as NaCl. Sorption of Ra2+ was generally greater than Sr2+, consistent with the frequent use of higher distribution coefficients for Ra in performance assessments

Non-specific abdominal pain and air pollution: a novel association.

We studied whether short-term exposure to air pollution was associated with non-specific abdominal pain in epidemiologic and animal studies. Patients visiting the emergency department with non-specific abdominal pain were identified in Edmonton (1992 to 2002, n = 95,173) and Montreal (1997 to 2002, n = 25,852). We calculated the daily concentrations for ozone (O(3)), nitrogen dioxide (NO(2)), sulfur dioxide (SO(2)), carbon monoxide (CO), and particles <10 (PM(10)) or <2.5 (PM(2.5)) µm. A case crossover study design was used to estimate the odds ratio (OR) and 95% confidence interval (CI) associated with an increase in the interquartile range of the air pollutants. We investigated differential effects by age and sex. Mice were gavaged with urban particle extracts. In animal models, colonic motility was tested, and visceral abdominal pain was measured using a writhing test, and behavioral response to oil of mustard and neostigmine. Motility and pain was measured acutely (1.5 hours after gavage) and chronically (7-days and 21-days after gavage). Emergency department visits for non-specific abdominal pain were primarily by women between the ages of 15-24 years. Individuals aged 15 to 24 years were at increased risk of non-specific abdominal pain in Edmonton (same day CO: OR = 1.04, 95% CI = 1.02-1.06; and NO(2): OR = 1.06, 95% CI = 1.03-1.09). The risk of air pollution among 15-24 year olds in Montreal was significantly positive (same day CO: OR = 1.11, 95% CI = 1.05-1.17; NO(2): OR = 1.09, 95% CI = 1.01-1.16; SO(2): OR = 1.17, 95% CI = 1.10-1.25; PM(2.5): OR = 1.09, 95% CI = 1.04-1.15). Abdominal pain was increased by an acute gavage of pollution extract but not to chronic exposure to pollutants. Colonic transit was delayed following chronic but not acute exposure with the pollutants. Epidemiological and animal data suggest that short-term exposure to air pollution may trigger non-specific abdominal pain in young individuals

Trust in the jury system: a comparison of Australian and U.S. samples

Public trust in the criminal justice system, including the jury system, is important for maintaining a democracy that is fair for all citizens. However, there is little research on trust in the jury system generally and even less cross-country comparison research specifically. Trust in the jury system might relate to other legal attitude measures (e.g., authoritarianism). This study identified the degree to which trust in the jury system relates to legal attitudes and compared perceptions of trust between the U.S. and Australia. Community members completed a survey that included measures of trust in the jury system and legal attitudes. The U.S. sample had higher levels of trust in juries than the Australian sample. In both samples, just world beliefs and legal authoritarianism were positively related to trust. Results have both theoretical and practical implications regarding legal attitudes, trust in the jury system, and public opinions of juries in each country