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The micropump is the executive component in a microfluidic chip which impels the sample to flow. Its performance directly affects the precision and reliability of Micro Total Analysis Systems (μTAS), and it also plays a key role in the targeting transport of trace substances. The single and double chamber valveless micropumps with saw-tooth microchannel were designed. The saw-tooth diffuser/nozzle pipe was fabricated on chrome glass substrate using MEMS technology and the pump diaphragm was manufactured by PMMA material. The piezoelectric bimorph with cantilever beam was adopted as driving pump actuator and PDMS material as pump diaphragm. The valveless micropumps for both single and double chambers were formed with different saw-tooth structure parameters. The flow rate increased about 25% when the sidewall of microchannel changed from smooth to saw-tooth, and with the driving voltage increasing, the positive and negative flow difference of saw-tooth diffuser/nozzle pipe increased significantly, so does the micro pump flow rate. The best diffused angle θ was determined by the microchannel length L of saw-tooth diffuser/nozzle pipe, and the micro pump operated with its maximum flow rate only when the length-width ratio A reached the best value. The flow rate of a saw-tooth diffuser/nozzle valveless micropump with parallel double chambers increased approximately 30% than that of a single chamber.

La0.7Sr0.3FeO3 materials with morphologies including nanoparticles, nanorods and nanowires were synthesized via a hydrothermal process assisted with different cetyltrimethyl ammonium bromide (CTAB) concentration. XRD, SEM and BET were used to characterize the morphology, composition and structural properties of the nanomaterials. The effect of CTAB concentration on morphology and growth mechanism of La0.7Sr0.3FeO3 was discussed. The gas sensing properties of La0.7Sr0.3FeO3 materials with different morphologies were also carried out in 0.1~ 100 ppm formaldehyde.

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Micro injection molding is competitive for fabrication of polymer-based micro-fluidic chips because of its high productivity. Unlike hot embossing, injection molding will not provide even molding condition for everywhere of the molded part. So the microchannels of an injection molded micro-fluidic chip need to be checked everyplace, while a hot embossed micro-fluidic chip can be checked only by one slice of the microchannels if only the micro protrusions of the mold stamp remain the same cross-sectional figure. Because an injection molded micro-fluidic chip has characteristics that its replication of the micro stamp protrusion is perfect in height but not satisfactory in width, especially for the width of the micro protrusion’s root which matches the molded microchannel’s opening, in this study micro flat photos of injection molded micro-fluidic chips were processed by our own image processing system developed from the image box of Matlab software. Measuring data about microchannels width from the micro flat photos were compared with measuring data obtained from a cross-sectional photo of one slice of the microchannels. Difference between data of these two measuring ways was less than 2% for opening width of the molded microchannel. So by image processing of the micro flat photos, rapid overall non-destructive testing of micro replication can be carried out for injection molded micro-fluidic chips.