Characterization of Metal and Metal Alloy Films as Contact Materials in MEMS Switches

This study presents a basic step toward the selection methodology of electric contact materials for microelectromechanical systems (MEMS) metal contact switches. This involves the interrelationship between two important parameters, resistivity and hardness, since they provide the guidelines and assessment of contact resistance, wear, deformation and adhesion characteristics of MEMS switches. For this purpose, thin film alloys of three noble metals, platinum (Pt), rhodium (Rh) and ruthenium (Ru) with gold (Au), were investigated. The interrelationship between resistivity and hardness was established for three levels of alloying of these metals with gold. Thin films of gold (Au), platinum (Pt), ruthenium (Rh) and rhodium (Ru) were also characterized to obtain their baseline data for comparison. All films were deposited on silicon substrates. When Ru, Rh and Pt are alloyed with Au, their hardness generally decreases but resistivity increases. This decrease or increase was, in general, dependent upon the amount of alloying

Application of advanced technologies to small, short-haul transport aircraft (STAT)

The benefits of selected advanced technologies for 19 and 30 passenger, short-haul aircraft were identified. Advanced technologies were investigated in four areas: aerodynamics, propulsion, structures, and ride quality. Configuration sensitivity studies were conducted to show design tradeoffs associated with passenger capacity, cabin comfort level, and design field length

Risk of blood splashes to the eye during surgery

Background. With the advent of a new infectious era involving the HIV and hepatitis B and C viruses, concern has arisen about transmission of these viruses through ocular blood splashes during surgery. The purpose of the study was to determine the risk of ocular blood splashes to surgeons and their assistants during surgery. Method. Surgeons and assistants in several surgical disciplines were requested to wear facemasks with a transparent plastic visor. The visors were collected postoperatively and inspected for macroscopic and microscopic blood splashes. Results. Fifty-nine per cent of the surgeons and assistants refused to wear facemasks with a visor. The incidence of blood splashes in those who participated was 45%. There was a trend for blood splashes to be more common during major surgery and during elective surgery. Surgeons and assistants were subject to similar risk. Conclusion. This study confirms the significant risk of ocular blood splashes during surgery, while also suggesting that both surgeons and assistants lack appreciation of the risk

Thermal Transport Properties of Dry Spun Carbon Nanotube Sheets

The thermal properties of carbon nanotube- (CNT-) sheet were explored and compared to copper in this study. The CNT-sheet was made from dry spinning CNTs into a nonwoven sheet. This nonwoven CNT-sheet has anisotropic properties in in-plane and out-of-plane directions. The in-plane direction has much higher thermal conductivity than the out-of-plane direction. The in-plane thermal conductivity was found by thermal flash analysis, and the out-of-plane thermal conductivity was found by a hot disk method. The thermal irradiative properties were examined and compared to thermal transport theory. The CNT-sheet was heated in the vacuum and the temperature was measured with an IR Camera. The heat flux of CNT-sheet was compared to that of copper, and it was found that the CNT-sheet has significantly higher specific heat transfer properties compared to those of copper. CNT-sheet is a potential candidate to replace copper in thermal transport applications where weight is a primary concern such as in the automobile, aircraft, and space industries

Cohomology of bundles on homological Hopf manifold

We discuss the properties of complex manifolds having rational homology of $S^1 \times S^{2n-1}$ including those constructed by Hopf, Kodaira and Brieskorn-van de Ven. We extend certain previously known vanishing properties of cohomology of bundles on such manifolds.As an application we consider degeneration of Hodge-deRham spectral sequence in this non Kahler setting.Comment: To appear in Proceedings of 2007 conference on Several complex variables and Complex Geometry. Xiamen. Chin