Application of Vertical Micororeactor Stack with Polystylene Microbeads to Immuno Assay
This paper proposes a vertical microreactor stack, a new concept of the microreactor, using vertical fluid flow operation and multifunctional fluid filters and vertically stacked reservoirs. The vertical fluid flow operation utilizes the surface tension of the liquid/ gas interface and pneumatic pressure to control the liquid behavior in vertical microreactor stack. The functions as microvalve, microcahnnel and micromixer of the fluid filter are estimated by computational fluid dynamics (CFD) simulation and experiments. The enzyme linked immuno-solvent assay is demonstrated by using vertical microreactor stack and the calibration curve was successfully taken.
Large area and wide dimension range x-ray lithography for lithographite, galvanoformung, and abformung process using energy variable synchrotron radiation
We developed an x-ray lithography system for the “lithographite, galvanoformung, and abformung” process using synchrotron radiation at the NewSUBARU facility of the University of Hyogo, Hyogo, Japan. The x-ray lithography system can utilize two different energy regions: one is a high-energy region: from 2 to 12 keV, and the other is a low-energy region from 1 to 2 keV. Each energy region can be selected in accordance with the size and shape of the desired microstructures. Large-area patterning across an A4-size area was successfully performed with a highly uniform pattern thickness. Furthermore, high-aspect-ratio patterning using a high-x-ray-energy region was also achieved using this x-ray lithography system.
Intensification of Bubble Disintegration and Dispersion by Mechanical Stirring in Gas Injection Refining
Water model experiments were performed for establishing highly efficient gas injection refining processes. Mechanical stirring was applied to disintegrate the injected bubbles and to disperse them widely in the bath. The bubble disintegration and dispersion were investigated by changing rotation mode (direction of rotation), rotation speed, blade size of the impeller and gas flow rate. Forward rotation of the impeller induced a stable tangential flow and could not disperse bubbles in the bath due to formation of a vortex around the impeller shaft. The tangential flow could be suppressed by forward–interrupt rotation, which could reduce the vortex formation to some degree. However, forward–interrupt rotation could not disperse the bubbles widely in the bath. Forward–reverse rotation could prevent the vortex formation completely and create a strong shear stress field, which intensified the bubble disintegration and dispersion in the bath. Higher impeller rotation speed and larger blade length in forward–reverse rotation could enhance the bubble disintegration and make the dispersed bubbles smaller. The bubble dispersion zone became wider with larger blade length. The bubble size tended to be larger at higher gas flow rates. However, its dependence on the gas flow rate became smaller at higher impeller rotation speed.