7,659 research outputs found

    Heterogeneous chemistry related to Antarctic ozone depletion: Reaction of ClONO2 and N2O5 on ice surfaces

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    Laboratory studies of heterogeneous reactions of possible importance for Antarctic ozone depletion were performed. In particular, the reactions of chlorine nitrate (ClONO2) and dinitrogen pentoxide (N2O5) were investigated on ice and HCl/ice surfaces. These reactions occur on the surfaces of polar stratospheric clouds (PSCs) over Antarctica. One reaction transforms the stable chlorine reservoir species (ClONO2 and HCl) into photochemically active chlorine in the form of HOCl and Cl2. Condensation of HNO3 in the reactions removes odd nitrogen from the stratosphere, a requirement in nearly all models of Antarctic ozone depletion. Other reactions may also be important for Antarctic ozone depletion. Like the reactions of chlorine nitrate, these reactions deplete odd nitrogen through HNO3 condensation. In addition, one reaction converts a stable chlorine reservior species (HCl) into photochemically active chlorine (ClNO2). These reactions were studied with a modified version of a Knudsen cell flow reactor

    Nuclear burst plasma injection into the magnetosphere and resulting spacecraft charging

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    The passage of debris from a high altitude ( 400 km) nuclear burst over the ionospheric plasma is found to be capable of exciting large amplitude whistler waves which can act to structure a collisionless shock. This instability will occur in the loss cone exits of the nuclear debris bubble, and the accelerated ambient ions will freestream along the magnetic field lines into the magnetosphere. Using Starfish-like parameters and accounting for plasma diffusion and thermalization of the propagating plasma mass, it is found that synchronous orbit plasma fluxes of high temperature electrons (near 10 keV) will be significantly greater than those encountered during magnetospheric substorms. These fluxes will last for sufficiently long periods of time so as to charge immersed bodies to high potentials and arc discharges to take place

    RESEARCH PRODUCTIVITY AND SELECTED CHARACTERISTICS OF AGRICULTURAL ECONOMICS FACULTY IN THE SOUTHERN REGION: A QUARTER OF A CENTURY LATER

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    Productivity and characteristics of southern agricultural economics faculty was compared to other regional faculty. With few exceptions, faculty members in the Southern region are as productive as their counterparts. We also found that the majority of respondents in all regions considered themselves in the top-quartile in all areas.Teaching/Communication/Extension/Profession,

    Research and education in management of large- scale technical programs Semiannual progress report

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    Research and education in management of large scale technical programs - education and integration of interdisciplinary tea

    What Works and Looking Ahead: A Comparative Study of UK and US Policies and Practices Facilitating Return to Work for People with Disabilities

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    Independent research organizations in the US and the UK were commissioned to review the research on ‘what works’ in facilitating return to work for people with disabilities, and to consider current developments in the light of the evidence. They produced two background papers for the UK/US Pathways to Work in the 21st Century Seminar. This paper aims to summarize the key points of interest in those US and UK papers. The view expressed here are those of the authors

    DETERMINANTS OF AGRICULTURAL ECONOMIC FACULTY SALARIES: A QUARTER OF A CENTURY LATER

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    Factors influencing the salaries of university agricultural economists were examined and compared to previous work. Results suggest the impact of publication output has remained relatively constant for the past 25 years, while other factors like grantsmanship have changed significantly. Additional analyses suggest significant impacts of appointment apportionment and Ph.D. programs.Teaching/Communication/Extension/Profession,

    The Fracking Revolution: Shale Gas as a Case Study in Innovation Policy

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    The early twenty-first century has witnessed a boom in oil and natural gas production that promises to turn the United States into a new form of petrostate. This boom raises various questions that scholars have begun to explore, including questions of risk governance, federalism, and export policy. Relatively neglected, however, have been questions of why the technological revolution behind the boom occurred and what this revolution teaches about innovation theory and policy. The boom in U.S. shale gas production reflected long-gestating infrastructure developments, a convergence of technological advances, government-sponsored research and development, the presence or absence of intellectual property rights, rights in tangible assets such as land and minerals, and tax and regulatory relief. Consequently, the story behind the boom reaches far beyond the risk-taking and persistence of George Mitchell, whose independent production company achieved pioneering success with hydraulic fracturing (fracking) in TexasÂż Barnett Shale. Indeed, the broader story demonstrates how a blend of distinct policy levers, reasonably adjusted over time, can combine to foster a diverse innovation ecosystem that provides a robust platform for game-changing innovation
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