Using Raman spectroscopy, we measure the optical phonon energies of suspended graphene before, during, and after thermal cycling between 300 and 700 K. After cycling, we observe large upshifts ( approximately 25 cm(-1)) of the G band frequency in the graphene on the substrate region due to compression induced by the thermal contraction of the underlying substrate, while the G band in the suspen...

This paper describes a simulation-based analysis of a printed circuit board (PCB) testing process. The PCBs are used in a defense application and the testing process is fairly complex. Boards are mounted on a test unit in batches and go through three thermal test cycles. As boards fail testing during the thermal cycling, operators can either replace the failed boards at fixed points during the ...

By detecting and quantitatively monitoring amplified DNA as PCR progresses, real-time PCR (quantitative or qPCR) instruments provide a robust approach for gene expression, genotyping, copy number variation, mutation screening, and methylation analysis. Data quality and reproducibility are governed by how robust a real-time PCR instrument’s thermal and optical systems are, with precise thermal c...

Title of Dissertation: EFFECT OF SURFACE FINISHES AND INTERMETALLICS ON THE RELIABILITY OF SnAgCu INTERCONNECTS Yunqi Zheng, Doctor of Philosophy, 2005 Dissertation directed by: Associate Professor F. Patrick McCluskey Department of Mechanical Engineering Power semiconductor devices are used in a wide range of applications, including power supplies and motor control. In these applications, powe...

Thermal barrier coating systems (TBCs) are used in gas turbines to prevent high-temperature degradation of metallic materials in the combustor and turbine. One of the main concerns regarding TBCs is poor reliability, and accurate life prediction models are necessary in order to fully utilise the beneficial effects of TBCs. This research project aims at developing deeper understanding of the deg...

Cycling of a metallic glass between ambient and cryogenic temperatures can induce higher-energy states characteristic formation on faster cooling. This rejuvenation, unexpected because it occurs at small macroscopic strains well below the thermally induced structural change, is important, for example, in improving plasticity. Molecular-dynamics simulations elucidate mechanisms by which thermal ...

This study evaluated the effect of alumina-blasting and three commercial adhesive primers on the shear bond strength of a dual-cured resin luting agent to zirconia ceramics. Two different-sized zirconia ceramic specimens were treated with or without alumina-blasting and then treated with one of three adhesive primers. Subsequently, specimens were cemented together with Linkmax HV (GC). Half of ...

This study evaluated the effect of zirconia framework design on fracture load of implant-supported zirconia-based prostheses after thermal cycling and mechanical loading. Three different zirconia framework designs were investigated: uniform-thickness (UNI), anatomic (ANA), and supported anatomic (SUP) designs. Each framework was layered with feldspathic porcelain (ZAC group) or indirect composi...

High thermal conductivity, low thermal expansion and low density are three important features in novel materials for high performance electronics, mobile applications and aerospace. Spark plasma sintering was used to produce light metal-graphite composites with an excellent combination of these three properties. By adding up to 50 vol.% of macroscopic graphite flakes, the thermal expansion coef...