1,705 research outputs found

    Evaluation of high specific-heat ceramic for regenerator use at temperatures between 2-30 K

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    Specific heat, thermal conductivity (both in the range 2-30 K), and microhardness data were measured on the ceramics labelled LS-8, LS-8A, and LS-8A doped with CsI, SnCl2, and AgCl. A work hardened sample of LS-8A was also studied in an effort to determine the feasibility of using these types of LS-8 materials to replace Pb spheres in the regenerator of the JPL cryocooler. The LS-8A materials are all more than an order of magnitude harder than Pb, and the dopants do not significantly improve the hardness. However, the SnCl2 dopant has a remarkable effect in improving the specific heat and thermal conductivity of LS-8A. The SnCl2 doping level which maximized the regenerator enthalpy change in going from an unloaded to a loaded condition was found to be 0.2 percent SnCl2 in LS-8A. It was also found that the enthalpy change for a regenerator employing the LS-8A material is more than three times larger than for the Pb spheres case. The use of rods, rather than spheres, of optimally doped LS-8A in regenerators is discussed

    Preparation of pure lithium hexafluoroarsenate Final report

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    Preparation and analysis of high purity lithium hexafluoroarsenat

    Gimbaled-shoulder friction stir welding tool

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    A gimbaled-shoulder friction stir welding tool includes a pin and first and second annular shoulders coupled to the pin. At least one of the annular shoulders is coupled to the pin for gimbaled motion with respect thereto as the tool is rotated by a friction stir welding apparatus

    Ireland's international trade and transport connections. ESRI WP573, October 2017

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    This paper looks at the transport patterns of Irish international trade. In particular, we examine how trade flows in weight differ from those measured by value and the implications that this has for transport mode and cost. In an environment of uncertainty relating to the impact of Brexit, the much larger share of the UK in total Irish export volumes (tonnages) compared to values signals possible significant impacts on transport and also on costs if increased customs procedures are introduced. We also look at the use of the UK as a land-bridge for Irish trade further afield, finding that a considerable percentage of Irish trade uses this transport option

    Long noncoding RNAs in liver cancer: what we know in 2014.

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    INTRODUCTION: Hepatocellular carcinoma (HCC) is the most common form of primary liver cancer with an estimated over half a million new cases diagnosed annually. Due to the difficulty in early diagnosis and lack of effective treatment options, HCC is currently ranked as the second highest neoplastic-related mortality in the world, with an extremely low 5-year survival rate of between 6 and 11%. Long noncoding RNAs (lncRNAs), are genes lacking protein coding ability, have recently emerged as pivotal participants in biological processes, often dysregulated in a range of cancers, including HCC. AREAS COVERED: In this review, we highlight the recent findings of lncRNAs in HCC pathogenesis, with particular attention on epigenetic events. In silico analysis was utilized to emphasize intrinsic linkages within the ncRNA families associated with hepatocarcinogenesis. EXPERT OPINION: While our understanding of lncRNAs in the onset and progression of HCC is still in its infancy, there is no doubt that understanding the activities of ncRNAs will certainly secure strong biomarkers and improve treatment options for HCC patients

    Thematic Analysis of Teacher Instructional Practices and Student Responses in Middle School Classrooms with Problem-Based Learning Environment

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    Problem-based learning (PBL) environment is a student-centered instructional method based on the use of ill-structured problems as a stimulus for collaborative learning. This study tried to gain an understanding of teachersΓÇÖ instructional practices and studentsΓÇÖ responses to such practices in middle school classrooms with PBL environment through qualitative analyses. A hybrid approach of inductive and deductive thematic analyses was employed and applied to field notes and transcripts of video observations of four PBL classrooms. To do so, a codebook was created based on the descriptions of roles of teachers and students in PBL classrooms in literature, and was then applied to inductive codes that emerged from the data. This study identified a number of specific instructional practices of teachers, as well as responses that students might engage in during PBL instructions. Being able to articulate these roles is an important step in helping new PBL teachers learn to facilitate student-centered classrooms

    Stakeholder Participation in the Environmental Clean Up of Radioactive Wastes in the United Kingdom, Japan and United States

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    We review our program of research on stakeholder participation with environmental cleanup from radioactive wastes in the United States, Japan and United Kingdom (e.g., [21,26,27,66]). Citizen participation programs in all three countries are at different stages: mature in the US, starting in Japan, and becoming operational in the UK. The US issue at the Savannah River Site (SRS) in South Carolina (SC) had been focused on citizens encouraging Federal (Department of Energy, or DOE; Environmental Protection Agency, or EPA) and State (SC's Department of Health and Environmental Compliance, or DHEC) agencies to aggressively pursue "Plug-in-RODs" at SRS to reduce the paperwork involved in order to accelerate the closure of seepage basins at SRS. The issue in Japan is an effective division of labor among participants and the representation of different perspectives in the deliberation process, including citizens. The UK issue is centered around effective citizen participation with the UK's Nuclear Decommissioning Authority (NDA). Looking at our program of research, our hope is that a review of the programs in these three countries may improve citizen advisory programs
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