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This article extends the findings from the Resources for Enhancing Alzheimer's Caregiver Health (REACH II) program, a multisite randomized clinical trial of a multicomponent psychosocial intervention, to improve the well-being of informal caregivers (CGs) of persons with dementia. We used residual change scores and stepwise hierarchical regression analyses to explore separately in 3 racial ethnic groups (Hispanic or Latino, Black or African American, and White or Caucasian) how the effects of the intervention were moderated by CG characteristics (sex, age, education, and relationship), CG resources (social support), and religious coping. The results indicated that CG's age and religious coping moderated the effects of the intervention for Hispanics and Blacks. The older Hispanic and Black CGs who received the intervention reported a decrease in CG burden from baseline to follow-up. Black CGs with less religious coping who received the intervention also reported a decrease in depressive symptoms from baseline to follow-up.

In this research, a fundamental study is conducted to identify the materials and develop the processes for producing barrier/bonding composite on Bi 2 Te 3 for high temperature thermoelectric applications. The composite must meet four basic requirements: (a) prevent interdiffusion between the electrode material, for our design, silver(Ag) and Bi 2 Te 3 , (b) bond well to Bi 2 Te 3 , (c) bond well to Ag electrode, and (d) do not themselves diffuse into Bi 2 Te 3 . The composites investigated include palladium (Pd), nickel/gold (Ni/Au), Ag, and titanium/gold (Ti/Au). After annealing at 250°C for 200 h, only the Ti/Au design meets all four requirements. The thickness of Ti and Au, respectively, is only 100 nm. Other than meeting these four requirements, the Ti/Au layers exhibit excellent step coverage on the rough Bi 2 Te 3 surface even after the annealing process.

We present a new technique for measuring the temperature profiles of visible LED chips by use of a nematic liquid crystal with IR laser illumination. The LEDs studied have a multi-quantum-well InGaN/GaN/sapphire structure. New features in this technique are the use of a high-power IR laser beam as the sensing light and the insertion of a color filter in the optical path to block the high-intensity LED light. For the LEDs measured, the conversion efficiency decreases by 70% when the junction temperature rises from 25 to 107 degrees C. This technique is a valuable tool for studying the performance of LEDs as a function of junction temperature.

The design, construction, and measurement of a compact vacuum furnace are reported. This type of furnace has many scientific applications in material processing and growth research. One example is the fluxless bonding process, where elevated temperature is needed to melt the solder and vacuum environment is required to inhibit solder oxidation. The primary objective of the furnace design is to keep the vacuum enclosure cool using only natural convection while allowing the heating platform to reach high temperature. This characteristic is necessary to enable us to seal the vacuum chamber using O-rings. To achieve this, the platform was designed to be thermally isolated from the chamber enclosure. Heat losses from the platform by conduction, convection, and radiation were analyzed. The dominating loss was found to be caused by the blackbody radiation, which can thus be used to estimate the relationship between platform temperature and the drive power needed. With a graphite platform of 75×75×25mm3, only 270W of power is needed to drive the platform to 400°C. At this temperature, the temperature of the furnace enclosure is below 55°C, allowing O-rings to be used to seal the vacuum chamber. Using a mechanical pump, the furnace can be pumped down to 40mTorr, which is low enough for our fluxless bonding processes. With a temperature controller, the platform temperature can be controlled within 1%. The heat-up time to 400°C is only 7min.

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The growth and stress vs. strain characterization of the silver solid solution phase with indium Silver solid solution phase with indium has been discovered to have great mechanical properties and anti-tarnishing property, as shown in the results of our previous study. It is important to know the stress vs. strain curve before adopting this material in industrial applications. The growth of the homogeneous silver solid solution phase with indium is first described. The X-ray diffraction (XRD) patterns and scanning electron microscope/energy dispersive X-ray spectroscopy (SEM/EDX) results are reported to verify the chemical composition of silver solid solution phase with indium samples. Based on the results, one could reversely determine the indium element composition in (Ag)exxIn solid solution by examining the lattice constant value using XRD for unknown compositions. The preparation of ASTM tensile test samples and tensile test experimental setting are explained in details. The intrinsic mechanical material properties of silver solid solution phase with indium, i.e., characteristic stress vs. strain curves, are presented and analyzed, with pure silver stress vs. strain curve in comparison. According to the experimental results, silver solid solution phase with indium exhibits low yield strength, high ultimate tensile strength, and large elongation value before fracture, compared to pure silver. In addition, fractography of the fracture surface of the tested sample has been studied to confirm the superior ductility of silver solid solution phase with indium. These superior mechanical properties may bring silver solid solution phase with indium new applications in various industries such as electronics and brazing.