Learn More
A thermal-bubble-actuated micropump by the principles of liquid/vapor phase transition and nozzle-diffuser flow regulation is successfully demonstrated. The micropump consists of a resistive heater, a pair of nozzle-diffuser flow controller and a 1 mm in diameter, 50 m in depth pumping chamber. The actuation mechanism comes from periodically nucleating and(More)
High-performance liquid chromatography-electrospray ionization mass spectrometry has been applied to analyze the flavonoids of Huangqi, the roots of Astragalus mongholicus and A. membranaceus. Eight flavonoids were identified as calycosin-7-O-beta-D-glucoside, calycosin-7-O-beta-D-glucoside-6"-O-malonate (2), ononin,(More)
A method of active frequency tuning on comb-shape micro resonators has been successfully demonstrated by means of localized stressing effects. A mechanical beam structure that can be resistively heated to generate thermal stress, is integrated as part of the comb-shape micro resonator for frequency tuning. Experimentally, a frequency change up to 6.5% is(More)
Polymeric microneedles fabricated by microinjection molding techniques have been demonstrated using Topas COC as the molding plastic material. Open-channel microneedles with cross-sectional area of 100 lm · 100 lm were designed and fabricated on top of a shank of 4.7 mm in length, 0.6 mm in width, and 0.5 mm in depth. The tip of the microneedle has a round(More)
A near-field electrospinning (NFES) process has been developed to deposit solid nanofibers in a direct, continuous, and controllable manner. A tungsten electrode with tip diameter of 25 microm is used to construct nanofibers of 50-500 nm line width on silicon-based collectors while the liquid polymer solution is supplied in a manner analogous to that of a(More)
Five years of photometric monitoring of the T Tauri star HBC 338 in NGC 1333 has revealed that it is a periodic variable, but the period has changed significantly with time. From 2000-2003, a period near 5.6 days was observed, while in the last two seasons, the dominant period is near 4.6 days. No other T Tauri star has been seen to change its period by(More)