1,872 research outputs found

    Numerical modeling tools for chemical vapor deposition

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    Development of general numerical simulation tools for chemical vapor deposition (CVD) was the objective of this study. Physical models of important CVD phenomena were developed and implemented into the commercial computational fluid dynamics software FLUENT. The resulting software can address general geometries as well as the most important phenomena occurring with CVD reactors: fluid flow patterns, temperature and chemical species distribution, gas phase and surface deposition. The physical models are documented which are available and examples are provided of CVD simulation capabilities

    Development of cathodic electrocatalysts for use in low temperature H2/O2 fuel cells with an alkaline electrolyte Second quarterly report, Oct. 1 - Dec. 31, 1965

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    Cathodic electrocatalysts for use in low temperature hydrogen-oxygen fuel cells with an alkaline electrolyte-corrosion resistance and activity testing of materials and element

    Deepwater and Other Sharks of the U.S. Atlantic Ocean Exclusive Economic Zone

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    Fifty-one deepwater and other shark species of the U.S. Exclusive Economic Zone in the Atlantic Ocean and Gulf of Mexico, which currently are not included in any Federal fishery management plan, are described, with a focus on primary distribution. Many of these shark species are not well known, while others which are more common may be of particular interest. Owing to concerns regarding possible increases in fishing effort for some of these species, as well as possible increases in bycatch rates as other fisheries move farther offshore, it is important that these sharks be considered in marine ecosystem management efforts. This will necessitate a better understanding of their biology and distribution. Primary distribution maps are included, based on geographic information system (GIS) analyses of both published and unpublished data, and a review of the literature. The most recent systematic classification and nomenclature for these species is used

    Thermal analysis of the vertical bridgman semiconductor crystal growth technique

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    The quality of semiconductor crystals grown by the vertical Bridgman technique is strongly influenced by the axial and radial variations of temperature within the charge. The relationship between the thermal parameters of the vertical Bridgman system and the thermal behavior of the charge are examined. Thermal models are developed which are capable of producing results expressable in analytical form and which can be used without recourse to extensive computer work for the preliminary thermal design of vertical Bridgman crystal growth systems. These models include the effects of thermal coupling between the furnace and the charge, charge translation rate, charge diameter, thickness and thermal conductivity of the confining crucible, thermal conductivity change and liberation of latent heat at the growth interface, and infinite charge length. The hot and cold zone regions, considered to be at spatially uniform temperatures, are separated by a gradient control region which provides added thermal design flexibility for controlling the temperature variations near the growth interface

    (2E)-3-(4-Chloro­phen­yl)-1-(4-hy­droxy­phen­yl)prop-2-en-1-one

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    In the title compound, C15H11ClO2, the dihedral angle between the mean planes of the chloro­benzene and hy­droxy­benzene rings is 6.5 (6)°. The mean plane of the prop-2-en-1-one group makes an angle of 18.0 (1)° with the hy­droxy­phenyl ring and 11.5 (1)° with the chloro­phenyl ring. The crystal packing is stabilized by inter­molecular O—H⋯O hydrogen bonds, weak C—H⋯O, C—H⋯π and π–π stacking inter­actions [centroid–centroid distances = 3.7771 (7) and 3.6917 (7) Å]

    A comprehensive framework for automotive sustainability assessment

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    Business efficiency, stakeholder pressure and the need for legislative compliance compel the automotive sector to design and manufacture fuel-efficient, low-impact, environmentally responsible and sustainable vehicles. Managing and responding to these multiple and sometimes conflicting interests requires the measurement of economic, environmental and societal performance. Although a number of automotive sustainability measures are mentioned within the literature, there is no single and unique approach for the complete and integrated sustainability assessment of vehicles. This study has developed a comprehensive automotive sustainability assessment framework by selecting a set of sustainability assessment criteria from the literature and refining these through an interview study with 24 automotive experts from academia, car manufacturers, consultancies and non-governmental organisations. Based on this approach, 26 midpoint and 9 end-point environmental, resource, social and economic impact categories have been identified for the construction of a framework for automotive sustainability assessment. The proposed framework can be used as a decision-supporting tool at the early stages of the vehicle development process. It allows source and sustainability issues to be identified throughout the entire vehicle life cycle and provides the means to sharpen analysis and discussion around these issues. The framework can also serve as a design structure for a wide range of sustainability assessment methods and tools (e.g. multi-criteria decision adding or sustainability accounting methods). It serves as guidance on what needs to be measured in an integrated sustainability assessment of vehicles and leaves the choice of what to include in the decision-making process to the discretion of individual companie

    Apparatus for growing crystals

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    An improved apparatus and method for growing crystals from a melt employing a heat pipe, consisting of one or more sections, each section serving to control temperature and thermal gradients in the crystal as it forms inside the pipe

    Insulin as a Primary Autoantigen for Type 1A Diabetes

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    Type 1A diabetes mellitus is caused by specific and progressive autoimmune destruction of the beta cells in the islets of Langerhans whereas the other cell types in the islet (alpha, delta, and PP) are spared. The autoantigens of Type 1A diabetes may be divided into subgroups based on their tissue distributions: Beta-cell-specific antigens like insulin, insulin derivatives, and IGRP (Islet-specific Glucose-6-phosphatase catalytic subunit Related Peptide); neurendocrine antigens such as carboxypeptidase H, insulinoma-associated antigen (IA-2), glutamic acid decarboxylase (GAD65), and carboxypeptidase E; and those expressed ubiquitously like heat shock protein 60 (a putative autoantigen for type 1 diabetes). This review will focus specifically on insulin as a primary autoantigen, an essentia l target for disease, in type 1A diabetes mellitus. In particular, immunization with insulin peptide B:9-23 can be used to induce insulin autoantibodies and diabetes in animal models or used to prevent diabetes. Genetic manipulation of the insulin 1 and 2 genes reciprocally alters development of diabetes in the NOD mouse, and insulin gene polymorphisms are important determinants of childhood diabetes. We are pursuing the hypothesis that insulin is a primary autoantigen for type 1 diabetes, and thus the pathogenesis of the disease relates to specific recognition of one or more peptides

    Faculty as Global Learners: Off-Campus Study at Liberal Arts Colleges

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    This co-authored collection offers valuable insights about the impact of leading off-campus study on faculty leaders’ teaching, research, service, and overall well-being. Recognizing that faculty leaders are themselves global learners, the book addresses ways that liberal arts colleges can more effectively achieve their strategic goals for students\u27 global learning by intentionally anticipating and supporting the needs of faculty leaders, as they grow and change. Faculty as Global Learners offers key findings and recommendations to stimulate conversations among administrators, faculty, and staff about concrete actions they can explore and steps they can take on their campuses to both support faculty leaders of off-campus programs and advance strategic institutional goals for global learning. This collection includes transferrable pedagogical insights and the perspectives of faculty members who have led off-campus study programs in a variety of disciplines and geographic regions.https://digitalcommons.trinity.edu/mono/1174/thumbnail.jp
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