45,537 research outputs found

    Thermal Conductivity Measurements of Wet Paper

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    The thermal conductivity of wet paper mats was studied as a function of moisture content and porosity. The conductivity measurements were conducted with a steady-state hot plate apparatus. Results show the relationship of conductivity and moisture content to be non-linear in an increasing fashion. Large variability in results obtained is largely attributed to experimental apparatus design and engineering. Solid cellulose conductivities were calculated using experimental results and the average value was found to be 0.317 ± 0.188 BTU/hr-ft-°F. Close correlation of data using different pulp furnishes indicate type of furnish is not a major variable in conductivity determinations

    Discovery of Two Moth Species New to Michigan (Lepidoptera: Noctuidae, Tortricidae)

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    Rhizedra lutosa (Noctuidae) and Argyrotaenia cockerellana (Tortricidae), are reported from Michigan for the first time, from remnant patches of mesic lakeplain prairie in Sumpter Township, Wayne Co. Rhizedra lutosa is a Eurasian species that is rapidly establishing populations across the United States. Argyrotaenia cockerellana is primarily known from the western United States, with eastern records from Nebraska and Ontario, Canada

    Great Diversity of Insect Floral Associates May Partially Explain Ecological Success of Poison Ivy (\u3ci\u3eToxicodendron Radicans\u3c/i\u3e Subsp. \u3ci\u3eNegundo\u3c/i\u3e [Greene] Gillis, Anacardiaceae)

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    Little is known about insect floral associates of poison ivy (Toxicodendron radicans, Anacardiaceae), despite the species’ ubiquity and importance in nature and society. Poison ivy’s pollination syndrome and results from prior studies suggest that the plant is not specialized for any particular pollinator type; however, a systematic survey exploring this hypothesis has been lacking. For this study, insect floral associates of Toxicodendron radicans subsp. negundo from a central Iowa site were observed during the flowering season of 2005. Thirty- seven distinct insect floral associates were observed: 8 coleopterans (beetles), 7 dipterans (flies), 2 hemipterans (true bugs), 19 hymenopterans (ants, bees, wasps), and 1 lepidopteran (butterfly). Hymenopterans appeared to be the most important contributors to poison ivy pollination on a per species basis; however, coleopterans and dipterans were also frequent associates. Poison ivy’s ability to utilize a diverse assemblage of insect pollinators may partially explain its ecological success in varied habitats

    Firm Incentives for Invention Prizes with Multiple Winners

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    This paper considers several multiple winner models where firms compete for invention prizes determined by the social planner. The short-run model, with a fixed number of firms, can result in negative expected societal benefit where welfare gains are totally dissipated. In the long-run model, with entry and exit, it is demonstrated that there is always a positive net welfare gain. The final model developed is one where the social planner sets the prize and the number of firms. Under certain conditions that model results in smaller total research expenditures than in the long-run model.
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