an electric field, electrons propagating through the FeCr/CeO2 layer from Si were injected into the Cr2O3-x layer. When a magnetic field was applied, the resistance of this capacitor above the flat-band voltage was reduced, causing the hysteresis window to become large. This result indicates that this capacitor, which contains a magnetic VX-661 price gate insulator, has the potential to be used in multilevel memories by the application of an external magnetic field. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3059406]“
“The accurate viscosity measurement of complex fluids is essential for characterizing fluidic behaviors in blood vessels and in microfluidic channels of lab-on-a-chip devices. A microfluidic platform that accurately
identifies biophysical properties of blood can be used as a promising tool for the early detections of cardiovascular and microcirculation diseases. In this study, a flow-switching phenomenon depending on hydrodynamic balancing in a microfluidic channel was adopted to conduct viscosity measurement of complex fluids with label-free operation. A microfluidic device for demonstrating this proposed method was designed to have two inlets for supplying the test and reference fluids, two side channels in parallel, and a junction channel connected to the midpoint of the two side channels. According to this proposed method, viscosities of various fluids with different phases (aqueous, oil, and blood) in relation to that of reference fluid were accurately determined Selleck PCI-34051 by measuring the switching flow-rate ratio between the test and reference fluids, when a reverse flow of the test or reference Z-VAD-FMK order fluid occurs in the junction channel. An analytical viscosity formula was derived to measure the viscosity of a test fluid in relation to that of the corresponding reference fluid using a discrete circuit model for
the microfluidic device. The experimental analysis for evaluating the effects of various parameters on the performance of the proposed method revealed that the fluidic resistance ratio (R-JL/R-L, fluidic resistance in the junction channel (R-JL) to fluidic resistance in the side channel (R-L)) strongly affects the measurement accuracy. The microfluidic device with smaller R-JL/R-L values is helpful to measure accurately the viscosity of the test fluid. The proposed method accurately measured the viscosities of various fluids, including single-phase (Glycerin and plasma) and oil-water phase (oil vs. deionized water) fluids, compared with conventional methods. The proposed method was also successfully applied to measure viscosities of blood with varying hematocrits, chemically fixed RBCS, and channel sizes. Based on these experimental results, the proposed method can be effectively used to measure the viscosities of various fluids easily, without any fluorescent labeling and tedious calibration procedures. (C) 2013 AIP Publishing LLC.