Mass flow rate measurement of thermal creep flow from transitional to slip flow regime

Measurements of the thermal creep flow through a single rectangular microchannel connected to two tanks maintained initially at the same pressure, but at different temperatures, are carried out for five noble gas species, over a large range of pressure and for two temperature differences between the tanks. The time-dependent pressure variations in both cold and hot tanks are investigated, and the temperature-driven (thermal creep) mass flow rate between two tanks is calculated from these data for the rarefaction parameter ranging from the transitional to slip flow regime. The measured mass flow rate is compared with the numerical solution of the S-model kinetic equation, and they show good agreement. A novel approximate expression to calculate the temperature-driven mass flow rate in the transitional and slip flow regimes is proposed. This expression provides results in good agreement with the measured values of the mass flow rate. In the slip flow regime, the thermal slip coefficient is calculated by employing the previously reported methodology, and the influence of the nature of the gas on this coefficient is investigated. The measured values of the thermal slip coefficient agree well with the values available in the literature, indicating that this coefficient is independent of the shape of a channel

Micro-Nano Mechatronics - New Trends in Material, Measurement, Control, Manufacturing and Their Applications in Biomedical Engineering

Micro/Nano mechatronics is currently used in broader spectra, ranging from basic applications in robotics, actuators, sensors, semiconductors, automobiles, and machine tools. As a strategic technology highlighting the 21st century, this technology is extended to new applications in bio-medical systems and life science, construction machines, and aerospace equipment, welfare/human life engineering, and other brand new scopes. Basically, the miniaturizing technology is important to realize high performance, low energy consumption, low cost performance, small space instrumentation, light-weight, and so on. This book presents the summary of our project Center of Excellence for Education and Research of Micro-Nano Mechatronics. The project implements a strategy to realize applications of micro-nano mechatronics, which are based on mechanical engineering or materials science, control systems engineering, and advanced medical engineering. The chapters describe the research advances in micro/nano measurement and control, micro/nano design and manufacturing, nano materials science, and their applications in biomedical engineering. The publication of this book was supported by Nagoya University, the 21st COE program ""Micro- and NanoMechatronics for Information-Based Society,"" and the global COE program “COE for Education and Research of Micro-Nano Mechatronics.” </span

Electrophoretic Separation on an Origami Paper-Based Analytical Device Using a Portable Power Bank

The electrophoresis of ampholytes such as amino acids on a paper device is difficult because of the variation of pH distribution in time. On the basis of this observation, we propose a paper-based analytical device (PAD) with origami structure. By folding a filter paper, a low operation voltage of 5 V was achieved, where the power was supplied by a 5 V 1.5 A portable power bank through the USB type A receptacle. As a demonstration, we carried out the electrophoretic separation of pI markers (pI 5.5 and 8.7). The separation was achieved within 4 min before the pH distribution on the paper varied. Though the separation distance was small, it could be increased by expanding the origami structure. This result indicates that our proposed PAD is useful for electrophoretic separation on a paper device