4,524 research outputs found

    Optical conductivity of alpha-Mn

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    The optical constants were measured at room temperature in the photon-energy range 0.6 to 6.5 eV on evaporated thin films. Evaporation conditions were chosen that gave the alpha-Mn crystal structure with reasonably large grains. The optical conductivity was separated into intraband and interband contributions by fitting to the Drude formula at low energies. The results are anomalous in comparison to other 3d transition metals. The free-electron lifetime is exceptionally sort (in agreement with the large dc resistivity of Mn), and the interband transitions seem unusually weak at the lower energies. Possible explanations related to the complicated crystal structure of alpha-Mn are discussed

    Evaluation report for secondary spacecraft cells - Cycle life test Annual report

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    Life cycle test evaluation of secondary spacecraft cell

    Optical conductivity of amorphous Ta and beta-Ta films

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    Tantalum films evaporated in high vacuum onto liquid-nitrogen-cooled substrates had an amorphous structure that persisted even after warming to room temperature. The optical conductivity (as well as the dc conductivity) of the amorphous films differed significantly from that of the bcc films

    Technology transfer: Transportation

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    The successful application of aerospace technology to problems related to highways and rail and rapid transit systems is described with emphasis on the use of corrosion resistant paints, fire retardant materials, and law enforcement. Possible areas for the use of spinoff from NASA technology by the California State Department of Corrections are identified. These include drug detection, security and warning systems, and the transportation and storage of food. A communication system for emergency services is also described

    Technology use by a college of education faculty and factors influencing integration of technology in an undergraduate teacher preparation program

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    This study describes current levels of technology use by a College of Education (COE) faculty and use of technology in teaching classes. In addition, the formation of a systematic plan for integrating technology throughout the teacher preparation programs was explored. Both quantitative and qualitative methods were used in this two-phase study; Phase I survey results suggested that although 93% of faculty believed technology in teacher education was very important or somewhat important, use of technology in teaching was limited. Consistent with previous findings on university faculty use of technology, COE faculty rated themselves as having high levels of knowledge and skill with using various computer-based technologies (i.e., word processing, computer spreadsheets, statistical computing, e-mail, educational software, presentation software, Internet/World Wide Web, and multimedia). However, this confidence did not necessarily transfer to use of technology in teaching. Over 50% of tenured/tenure-track faculty reported use of technology in teaching at least once during the Spring 1997 semester while no more than 30% of affiliate faculty reported using it in teaching; Phase II case study data were collected from interviews, observations, and documents. Data were examined using the framework developed by Fullan and Hargreaves (1996): (a) teacher\u27s purpose, (b) teacher as person, (c) context of teaching, and (d) culture of teaching; Findings describe the manner in which case study participants used technology in their teaching as an add-on, a communication medium, a resource, and a teaching/learning tool. Commitment, a factor within teacher as person, was found to be a critical element in adopting use of technology in teaching regardless of an individual\u27s technology expertise. Efforts to plan for systematic integration of technology throughout the COE teacher preparation programs were met by resistance due to the issue of academic freedom and more pressing concerns such as reorganization of the COE; Although findings of this study are limited to one COE setting, a complex variety of factors influencing the integration of technology in teacher education are described, and the importance of support personnel is reinforced. Recommendations for other colleges of education attempting to integrate technology into teacher education programs are included

    Addressing Funding Disparities in Women of Color-led Organizations

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    Women of color who are founders and/or leaders of nonprofit organizations typically come from the communities they serve. While their experience within their communities gives them an edge on service delivery and impact, these leaders face funding disparities compared to other organizations. This report highlights the stories and experiences of three women of color founders and nonprofit leaders to provide insight into the funding barriers and how to mitigate these barriers. Suggestions for improvement include Trust based philanthropy, listening sessions, and Women of color-leader development circles
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