6,955 research outputs found

    Salt stabilizer for preventing chlorine depletion and increasing shelf-life of potable water - A concept

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    Proposed concept, based on law of mass action uses addition of salt to increase chlorine ions produced in sodium hydrochlorite solutions, thereby increasing solution shelf-life. This technique is not costly. Usefulness will be determined by acceptability of salt in product undergoing long shelf-life

    Environmental test planning, selection and standardization aids available

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    Requirements for instrumentation, equipment, and methods to be used in conducting environmental tests on components intended for use by a wide variety of technical personnel of different educational backgrounds, experience, and interests is announced

    Attractor solutions for general hessence dark energy

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    As a candidate for the dark energy, the hessence model has been recently introduced. We discuss the critical points of this model in almost general case, that is for arbitrary hessence potential and almost arbitrary hessence-background matter interaction. It is shown that in all models, there always exist some stable late-time attractors. It is shown that our general results coincide with those solutions obtained earlier for special cases, but some of them are new. These new solutions have two unique characteristics. First the hessence field has finite value in these solutions and second, their stabilities depend on the second derivative of the hessence potential.Comment: 11 pages. Add some explanations about the autonomousity of the equations, and also a conclusion section was added. To appear in Phys. Rev. D (2006

    Research approaches to alleviation of airport-community noise

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    Airport-community noise reduction problem

    Some aspects of thermal inflation: the finite temperature potential and topological defects

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    Currently favoured extensions of the Standard Model typically contain `flaton fields' defined as fields with large vacuum expectation values (vevs) and almost flat potentials. If a flaton field is trapped at the origin in the early universe, one expects `thermal inflation' to take place before it rolls away to the true vacuum, because the finite-temperature correction to the potential will hold it at the origin until the temperature falls below 1\TeV or so. In the first part of the paper, that expectation is confirmed by an estimate of the finite temperature corrections and of the tunneling rate to the true vacuum, paying careful attention to the validity of the approximations that are used. The second part of the paper considers topological defects which may be produced at the end of an era of thermal inflation. If the flaton fields associated with the era are GUT higgs fields, then its end corresponds to the GUT phase transition. In that case monopoles (as well as GUT higgs particles) will have to be diluted by a second era of thermal inflation. Such an era will not affect the cosmology of GUT strings, for which the crucial parameter is the string mass per unit length. Because of the flat Higgs potential, the GUT symmetry breaking scale required for the strings to be a candidate for the origin of large scale structure and the cmb anisotropy is about three times bigger than usual, but given the uncertainties it is still compatible with the one required by the unification of the Standard Model gauge couplings. The cosmology of textures and of global monopoles is unaffected by the flatness of the potential.Comment: 40 pages, LaTeX with epsf macro, 1 figure, preprint number correcte

    Geology of the Upper Middle Creek Area Huerfano County, Colorado

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    The Sangre de Cristo Mountains of Colorado and New Mexico are, geologically speaking, relatively unknown. The equivocal nature of our knowledge of the range was a primary reason for studying a portion of it in some detail. Most of the previous studies have been concerned with the northern part of the range in Colorado, in the general area between Salida and La Veta Pass. This work has indicated that the complicated structure which characterizes the northern part of the range becomes simpler to the south. Therefore, a second objective of the current study has been to test this hypothesis. Thirdly, since the structure was assumed to be less complicated, it was thought that the depositional and tectonic history of the southern area might be easier to decipher and would thus be a useful guide to the depositional and tectonic history of the more intensely deformed areas. Advisor: Russell Smit

    Use of LARS system for the quantitative determination of smoke plume lateral diffusion coefficients from ERTS images of Virginia

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    A technique for measuring smoke plume of large industrial sources observed by satellite using LARSYS is proposed. A Gaussian plume model is described, integrated in the vertical, and inverted to yield a form for the lateral diffusion coefficient, Ky. Given u, wind speed; y sub l, the horizontal distance of a line of constant brightness from the plume symmetry axis a distance x sub l, downstream from reference point at x=x sub 2, y=0, then K sub y = u ((y sub 1) to the 2nd power)/2 x sub 1 1n (x sub 2/x sub 1). The technique is applied to a plume from a power plant at Chester, Virginia, imaged August 31, 1973 by LANDSAT I. The plume bends slightly to the left 4.3 km from the source and estimates yield Ky of 28 sq m/sec near the source, and 19 sq m/sec beyond the bend. Maximum ground concentrations are estimated between 32 and 64 ug/cu m. Existing meteorological data would not explain such concentrations

    Inflation From Symmetry Breaking Below the Planck Scale

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    We investigate general scalar field potentials \hbox{V(ϕ)V\left(\phi\right)} for inflationary cosmology arising from spontaneous symmetry breaking. We find that potentials which are dominated by terms of order ϕm\phi^m with \hbox{m>2m > 2} can satisfy observational constraints at an arbitrary symmetry breaking scale. Of particular interest, the spectral index of density fluctuations is shown to be independent of the specific form of the potential, depending only on the order mm of the lowest non-vanishing derivative of V(ϕ)V(\phi) near its maximum. The results of a model with a broken SO(3){\rm SO(3)} symmetry illustrate these features.Comment: Submitted to Phys. Rev. Letters. 7 Pages, REVTeX. No figure

    Fanny Copeland and the geographical imagination

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    Raised in Scotland, married and divorced in the English south, an adopted Slovene, Fanny Copeland (1872 – 1970) occupied the intersection of a number of complex spatial and temporal conjunctures. A Slavophile, she played a part in the formation of what subsequently became the Kingdom of Yugoslavia that emerged from the First World War. Living in Ljubljana, she facilitated the first ‘foreign visit’ (in 1932) of the newly formed Le Play Society (a precursor of the Institute of British Geographers) and guided its studies of Solčava (a then ‘remote’ Alpine valley system) which, led by Dudley Stamp and commended by Halford Mackinder, were subsequently hailed as a model for regional studies elsewhere. Arrested by the Gestapo and interned in Italy during the Second World War, she eventually returned to a socialist Yugoslavia, a celebrated figure. An accomplished musician, linguist, and mountaineer, she became an authority on (and populist for) the Julian Alps and was instrumental in the establishment of the Triglav National Park. Copeland’s role as participant observer (and protagonist) enriches our understanding of the particularities of her time and place and illuminates some inter-war relationships within G/geography, inside and outside the academy, suggesting their relative autonomy in the production of geographical knowledge
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