14 research outputs found

    Climate Change Impacts on Iowa, 2010

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    Climate change is already affecting the way Iowans live and work. Without action to mitigate these effects, our future responses will become more complex and costly . The following policy recommendations are offered as initial steps to help safeguard our state’s economy, environment, and residents

    Lynx Mission Concept Status

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    Lynx is a concept under study for prioritization in the 2020 Astrophysics Decadal Survey. Providing orders of magnitude increase in sensitivity over Chandra, Lynx will examine the first black holes and their galaxies, map the large-scale structure and galactic halos, and shed new light on the environments of young stars and their planetary systems. In order to meet the Lynx science goals, the telescope consists of a high-angular resolution optical assembly complemented by an instrument suite that may include a High Definition X-ray Imager, X-ray Microcalorimeter and an X-ray Grating Spectrometer. The telescope is integrated onto the spacecraft to form a comprehensive observatory concept. Progress on the formulation of the Lynx telescope and observatory configuration is reported in this paper

    Advanced Guidance and Control for Hypersonics and Space Access

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    Advanced guidance and control (AG&C) technologies are critical for meeting safety, reliability, and cost requirements for the next generation of reusable launch vehicle (RLV), whether it is fully rocket-powered or has air- breathing components. This becomes clear upon examining the number of expendable launch vehicle failures in the recent past where AG&C technologies could have saved a RLV with the same failure mode, the additional vehicle problems where t h i s technology applies, and the costs and time associated with mission design with or without all these failure issues. The state-of-the-art in guidance and control technology, as well as in computing technology, is the point where we can look to the possibility of being able to safely return a RLV in any situation where it can physically be recovered. This paper outlines reasons for AWC, current technology efforts, and the additional work needed for making this goal a reality. There are a number of approaches to AG&C that have the potential for achieving the desired goals. For some of these methods, we compare the results of tests designed to demonstrate the achievement of the goals. Tests up to now have been focused on rocket-powered vehicles; application to hypersonic air-breathers is planned. We list the test cases used to demonstrate that the desired results are achieved, briefly describe an automated test scoring method, and display results of the tests. Some of the technology components have reached the maturity level where they are ready for application to a new vehicle concept, while others are not far along in development

    Investigations of diesel injector deposits characterization and testing

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    Over the last decade, there has been an impetus in the automobile industry to develop new diesel injector systems, driven by a desire to reduce fuel consumption and proscribed by the requirement to fulfil legislation emissions. The modern common-rail diesel injector system has been developed by the industry to fulfil these aspirations, designed with ever-higher tolerances and pressures, which have led to concomitant increases in fuel temperatures after compression with reports of fuel temperatures of ~150°C at 1500-2500 bar. This engineering solution in combination with the introduction of Ultra Low Sulphur diesel fuel (ULSD) has been found to be highly sensitive to deposit formation both external injector deposits (EDID) and internal (IDID). The deposits have caused concerns for customers with poor spray patterns misfiring injector malfunction and failure, producing increased fuel consumption and emissions. The importance to the industry of understanding the nature of diesel injector deposits has led to significant research in this area with a number of industry tests being developed. However, the introduction of new generation fuels e.g. hydrogenated vegetable oil (HVO) and the reports of injector problems such as “abrasive particles” in Europe continue to stimulate investigation. The interest in characterizing diesel injector deposits has also seen a number of recent contributions being published. Many of these reports describe analyses that either consider only the surface of deposits or use methods which destroy any provenance. In this paper, we will describe the latest data from the deployment of modern analytical techniques to characterize these deposits. As a further contribution to the understanding of diesel injector deposits, this paper will describe the use of Principal Component Analysis (PCA) in conjunction with Time of Flight Secondary Ion Mass spectrometry (ToF-SIMS) to determine trends in IDID chemistries worldwide. The application of the ToF-SIMS technique to EIDS will be described. The latest industry standard engine tests will be discussed with regard to the chemistries involved and the latest advances in the application of a new generation of deposit control additives (DCA) will be described

    Climate Change Impacts on Iowa, 2010

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    Climate change is already affecting the way Iowans live and work. Without action to mitigate these effects, our future responses will become more complex and costly . The following policy recommendations are offered as initial steps to help safeguard our state’s economy, environment, and residents.</p

    Testing the Role of Charge and Structure on the Stability of Peptide–Porphyrin Complexes

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    This study aims to extend a structural and biophysical understanding of a coiled-coil based peptide model system that serves as a scaffold for the anionic porphyrin, TPPS<sub>4</sub>. This is part of an ongoing biomaterials effort to create photoelectronically active mesoscale fibrils for surface deposition and characterization of conductivity properties. The goals are two-fold: (1) to explore optimal basic side-chain moieties for tight binding to TPPS<sub>4</sub> and (2) to test the binding of various metalated TPPS<sub>4</sub> derivatives to our peptide model system. The latter goal is to control the electronic and redox properties of the fibrillar biomaterials. A soluble version of the peptide biomaterial was used in order to probe binding and to extract thermodynamically rigorous equilibrium binding constants. UV–visible spectroscopy and circular dichroism spectropolarimtery are used to measure the effects of binding on the Soret band of the porphyrin and the helical signal of the peptide, respectively. For the first study, it was found that lysine, ornithine, and arginine are equally robust at engaging TPPS<sub>4</sub> with low micromolar binding affinity. In the case of the metalated porphyrins, submicromolar binding affinity was observed for Cu­(II), Ni­(II), and Pd­(II). The ability of these metalated porphyrins to bind with high affinity is dependent largely on structural perturbations of the porphyrin molecule, rather than on induced electronic effects
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