70,061 research outputs found

    VirginiaNavigator/GWEP Community Outreach Training for Older Adults, Caregivers, and Service Programs

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    Educational Objectives 1. Demonstrate how VirginiaNavigator (VN) can support self-care and connecting with community resources. 2. Discuss how VN can assist service providers who work with older adults and their families. 3. Explain how VN relates to six focus areas of the Geriatrics Workforce Enhancement Program (GWEP) to improve the well-being of older adults

    Thermodynamics and kinetics of the undercooled liquid and the glass transition of the Zr41.2Ti13.8Cu12.5Ni10.0Be22.5 alloy

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    Differential scanning calorimetry (DSC) was used to determine the thermodynamic functions of the undercooled liquid and the amorphous phase with respect to the crystalline state of the Zr41.2Ti13.8Cu12.5Ni10.0Be22.5bulk metallic glass forming alloy. The specific heat capacities of this alloy in the undercooled liquid, the amorphous state and the crystal were determined. The differences in enthalpy, ∆H, entropy, ∆S, and Gibbs free energy, ∆G, between crystal and the undercooled liquid were calculated using the measured specific heat capacity data as well as the heat of fusion. The results indicate that the Gibbs free energy difference between metastable undercooled liquid and crystalline solid, ∆G, stays small compared to conventional metallic glass forming alloys even for large undercoolings. Furthermore, the Kauzmann temperature, TK, where the entropy of the undercooled liquid equals to that of the crystal, was determined to be 560 K. The Kauzmann temperature is compared with the experimentally observed rate-dependent glass transition temperature, Tg. Both onset and end temperatures of the glass transition depend linearly on the logarithm of the heating rate based on the DSC experiments. Those characteristic temperatures for the kinetically observed glass transition become equal close to the Kauzmann temperature in this alloy, which suggests an underlying thermodynamic glass transition as a lower bound for the kinetically observed freezing process

    In situ transmission electron microscopy studies of shear bands in a bulk metallic glass based composite

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    In situ straining transmission electron microscopy (TEM) experiments were performed to study the propagation of the shear bands in the Zr56.3Ti13.8Cu6.9Ni5.6Nb5.0Be12.5 bulk metallic glass based composite. Contrast in TEM images produced by shear bands in metallic glass and quantitative parameters of the shear bands were analyzed. It was determined that, at a large amount of shear in the glass, the localization of deformation occurs in the crystalline phase, where formation of dislocations within the narrow bands are observed

    A Ground Water Quality Summary for Alaska: a Termination Report

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    The expanding economic activity throughout the State of Alaska has created an urgent demand for water resource data. Ground water quality information is of particular interest since this is the most used source for domestic and industrial supplies. Many agencies and individuals have accumulated large quantities of data but their value has been marginal due to a lack of distribution to potential users. It was the original intent of the work reported herein to gather, collate, and publish all ground water quality data available in the files of university, state, and federal laboratories. Soon after the inception of the project the major contributor, the U.S. Geological Survey, found it was administratively impossible to contribute either the monies or the data necessary to accomplish the ultimate goals of the project -- An Atlas on Alaskan Ground Water Qualities. At the time the above decision was made the Institute felt too much information was on hand to allow it to lay fallow. Therefore, this report was prepared, In a more limited scope than originally planned, to fill the need for a readily available source of information.The work upon which this report is based was supported by funds provided by the U.S. Department of the Interior, Office of Water Resources Research, Project Number A-024-ALAS and Agreement Number 14-01-0001-1070

    Microstructure Controlled Shear Band Pattern Formation and Enhanced Plasticity of Bulk Metallic Glasses Containing in situ Formed Ductile Phase Dendrite Dispersions

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    Results are presented for a ductile metal reinforced bulk metallic glass matrix composite based on glass forming compositions in the Zr-Ti-Cu-Ni-Be system. Primary dendrite growth and solute partitioning in the molten state yields a microstructure consisting of a ductile crystalline Ti-Zr-Nb β phase, with bcc structure, in a Zr-Ti-Nb-Cu-Ni-Be bulk metallic glass matrix. Under unconstrained mechanical loading organized shear band patterns develop throughout the sample. This results in a dramatic increase in the plastic strain to failure, impact resistance, and toughness of the metallic glass

    Eagle Scouts: Merit beyond the Badge

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    Previous studies have shown that participation in Scouting produces better citizens.6 And, there is no shortage of examples or anecdotal accounts that would affirm these findings. Surprisingly, however, there is very little scientific evidence to confirm the prosocial benefits associated with Scouting or earning the rank of Eagle Scout. Thus, the central question of this study is to determine if participation in Scouting and ultimately becoming an Eagle Scout is associated with prosocial behavior and positive youth development that carries over into young adulthood and beyond

    Large supercooled liquid region and phase separation in the Zr–Ti–Ni–Cu–Be bulk metallic glasses

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    Results of calorimetric, differential thermal analysis, and structural measurements are presented for a series of bulk metallic glass forming compositions in the Zr-Ti-Cu-Ni-Be alloy system. The calorimetric data for five alloys, prepared along the tie line between phase separating and nonphase separating compositions, show that the transition from phase separating to nonphase separating behavior is smooth. The bulk glasses near the center of the tie line exhibit large supercooled liquid regions: Delta T approximate to 135 K, the largest known for a bulk metallic glass

    Tying Knots With Communities: Youth Involvement in Scouting and Civic Engagement in Adulthood

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    Using data from a nationally representative sample of American adult males (N = 2,512), this study examines (a) whether duration of membership in the Boy Scouts of America is associated with adult civic engagement and (b) whether five characteristics of positive youth development (confidence, competence, connection, character, and caring) account for the relationship between duration of Scouting membership and adult civic engagement. The results from structural equation modeling indicate that duration of participation in Scouting is positively associated with four indicators of civic engagement: community involvement, community volunteering, community activism, and environmental activism. Among the five positive characteristics, confidence and competence were found to fully mediate the effects of Scouting on all four types of civic engagement, whereas the other three only to partly mediate the effects

    Multiplexed broadband beam steering system utilizing high speed MEMS mirrors

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    We present a beam steering system based on micro-electromechanical systems technology that features high speed steering of multiple laser beams over a broad wavelength range. By utilizing high speed micromirrors with a broadband metallic coating, our system has the flexibility to simultaneously incorporate a wide range of wavelengths and multiple beams. We demonstrate reconfiguration of two independent beams at different wavelengths (780 and 635 nm) across a common 5x5 array with 4 us settling time. Full simulation of the optical system provides insights on the scalability of the system. Such a system can provide a versatile tool for applications where fast laser multiplexing is necessary.Comment: 11 pages, 6 figures, submitte
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