There is great interest in using microfluidic channels packed with a stationary phase for chemical separations of complex mixtures. A key advantage of such techniques is the use of electroosmotic flow (EOF), controlled simply by applying electrical potentials between reservoirs. A disadvantage for this technique, however, is a lack of compatibility with gradient elution separations. This limita...

Two fused-silica capillaries of considerably different inner diameter (75 and 10 microm) were used for the separation of a set of five standard proteins. The separations were run in acid pH (50 mM phosphate buffer, pH 2.5). Generally better separations (with minor tailing only) were obtained using a standard capillary [27 cm (20 cm effective length)x 75 microm I.D.] in comparison with a narrow ...

The magnitude and direction of the electro-osmotic flow (EOF) inside a microfabricated fluid channel can be controlled by a perpendicular electric field of 1.5 megavolts per centimeter generated by a voltage of only 50 volts. A microdevice called a "flowFET," with functionality comparable to that of a field-effect transistor (FET) in microelectronics, has been realized. Two flowFETs integrated ...

The drive mode of fluid body in microchannel is a key in microfluidic control system. ElectroOsmotic MicroPump (EOP) is a microfluidic system which is controlled by electric field with no moving parts. EOPs are attracting increasing attention due to the ease of fluid control in complex microchannels. The theory of forming Electro-Osmotic-Flow (EOF) is analyzed and governing equations are given ...

Capillary electrochromatography (CEC) combines the separation principle of HPLC (partitioning between mobile and stationary phases) with the high efficiency of capillary electroseparation methods. In CEC the electroosmotic flow (EOF) inherent in capillary electrophoretic separations is used to transport solute and mobile phase through a packed capillary column. The properties of the EOF provide...

Due to the chaotic nature of atmospheric dynamics, numerical weather prediction systems are sensitive to errors in the initial conditions. To estimate the forecast uncertainty, forecast centres produce ensemble forecasts based on perturbed initial conditions. How to optimally perturb the initial conditions remains an open question and different methods are in use. One is the singular vector (SV...

Active development of compact analytical instruments suitable for point-of-care testing (POCT) requires optimization of existing methods. To aid the development of capillary gel electrophoresis instruments for POCT, we attempted to separate polymerase chain reaction products (small DNAs) using a short, fused silica capillary coated with an acrylamide (AM)/acrylic acid (AA) copolymer (poly(AM-co...

Abstract The variability of the zonal-mean large-scale extratropical circulation is often studied using individual modes obtained from empirical orthogonal function (EOF) analyses. prevailing reduced-order model leading EOF (EOF1) zonal wind, called annular mode, consists an eddy–mean flow interaction mechanism that results in a positive feedback EOF1 onto itself. However, few studies have poin...

AIM To assess the feasibility and safety of early oral feeding (EOF) after gastrectomy for gastric cancer through a systematic review and meta-analysis based on randomized controlled trials. METHODS A literature search in PubMed, Embase, Web of Science and Cochrane library databases was performed for eligible studies published between January 1995 and March 2014. Systematic review was carried...

Non-uniform heat flux generated by microchips causes “hot spots” in very small areas on the microchip surface. These hot spots are generated by the logic blocks in the microchip bay; however, memory blocks generate lower heat flux in contrast. The goal of this research is to design, fabricate, and test an active cooling, micro-channel heat sink device that can operate under atmospheric pressure...