) was optimized to process the μPIV images into a raw vector map
in real time and to transfer the map to a database in the PC. The processor employed cross-correlation to calculate the velocity vectors. A total of 800 sets of data was taken at each location for a specified Saracatinib manufacturer Reynolds number (Re; i.e., the ratio of inertial forces to viscous forces). The selection of 800 data sets was based on the examination of the data convergence. One set PRN1371 of data consisted of five PIV vector data for a 32 × 32 pixel interrogation area. These data were statistically averaged, and the mean vector fields were obtained and used for the examination of the flow structure. The measurements were performed in a clean room at the University Microsystem Laboratory at a controlled ambient temperature of 298 K. Methodology used (for electrophoretic mobility of DNA molecules and buffer solution EOF velocity)
and temperature visualization Following [7], the electrophoretic velocity of the stained DNA molecules in the untreated buy Stattic PDMS channel with negligible electro-osmotic mobility was measured using μPIV measurements. The total velocity of the seed particles (i.e., DNA molecules) can also be measured through the μPIV measurements for treated PDMS channels. With these velocities found, the bulk averaged EOF velocity of the fluid (u) could be obtained following equation (1) below: (1) where is the total velocity of the seed particles (i.e., DNA molecules) by μPIV in treated PDMS
channels, and is the electrophoretic velocity of the DNA molecules Mannose-binding protein-associated serine protease in the untreated PDMS channel. With respect to measurement uncertainties, the most significant source of error was expected to be the measurements at the wall, and the biggest physical error in the μPIV data was the Brownian diffusion of the stained DNA molecules. Out-of-plane Brownian diffusion causes a reduction of the signal-to-noise ratio of the cross-correlation peak, and such an error was estimated. Errors due to in-plane Brownian diffusion were essentially eliminated by temporally averaging the results in the steady flow. In fact, experimental errors due to the limiting spatial resolution of the CCD camera, as well as errors in determining magnification, were therefore the major source of error in these results and found to be within ±15%. Visualization of the local fluid temperature was achieved with the same apparatus used for flow visualization and measurements (see Figure 3). Instead of using fluorescent particles, however, the channel was filled with a solution of rhodamine B, a fluorescent dye which shows a temperature-sensitive quantum yield in the range of 0°C to 100°C [5]. Experiments were conducted with a fluorescence microscope equipped with a long-working distance ×10 objective lens. The images were recorded with the same equipment used for the μPIV measurements. From the captured images, the detailed temperature distribution could be extracted.