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The University of Arkansas at Little Rock (UALR) partnered with three agencies and select local high schools to instruct students on the principles and applications of fuel cells and key environmental issues. The three participating agencies were the Arkansas Department of Economic Development Energy Office (ADED), the Arkansas Department of Environmental Quality (ADEQ), and Entergy Corporation (an energy services company). Three high schools were selected, and the project was successfully implemented during Fall 2003 and Spring 2004. This paper presents the experiences of a university professor and an undergraduate student teaching the principles of fuel cells to high-school students and assessing their reactions to learning new technology. The paper also highlights the effectiveness of collaboration between state agencies, universities, and high schools.

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Microfluidic systems are important in a variety of applications such as DNA sequencing, cell separation, environmental monitoring, heat transportation in spacecraft and space station [1–2]. Micromixers are the most important component in microfluidic systems and they can be classified as active and passive micromixers [3]. In micro dimensions, surface forces dominate over body forces requiring special attention for problems involving two-phase flows with free surfaces which are often driven by capillary forces [4]. In the present work the flow and mixing process in a passive microchannel mixer were numerically investigated. Effects of velocity, surface tension, and contact angle on the two phase flow were studied. Numerical results are obtained with a finite volume CFD code and using structured grids. Different liquids-gas Reynolds number ratios (Reliquid/Regas) were used ranging from 4 to 42. In addition, five values of the contact-angle (0 – 120) and seven values of the liquid surface tension (0.02 – 0.1) were used. Results show that increasing Reliquid increases the rate of the development of the air bubble. Increased surface tension resulted in increased bubble length. Bubble length decreased with increased contact angle till 75 degrees and further increase resulted in increased bubble length.