Mixing liquids at the micro-scale is difficult because the low Reynolds numbers in microchannels and in microreactors prohibit the use of conventional mixing techniques based on mechanical actuators and induce turbulence. Static mixers can be used to solve this mixing problem. This paper presents micromixers with geometries very close to conventional large-scale static mixers used in the chemical and food-processing industry. Two kinds of geometries have been studied. The first type is composed of a series of stationary rigid elements that form intersecting channels to split, rearrange and combine component streams. The second type is composed of a series of short helix elements arranged in pairs, each pair comprised of a right-handed and left-handed element arranged alternately in a pipe. Micromixers of both types have been designed by CAD and manufactured with the integral microstereolithography process, a new microfabrication technique that allows the manufacturing of complex three-dimensional objects in polymers. The realized mixers have been tested experimentally. Numerical simulations of these micromixers using the computational fluid dynamics (CFD) program FLUENT are used to evaluate the mixing efficiency. With a low pressure drop and good mixing efficiency these truly three-dimensional micromixers can be used for mixing of reactants or liquids containing cells in many microTAS applications.

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Mixing liquids on the micro-scale is difficult because the low Reynolds numbers in microchannels and in microreactors prohibit the use of conventional mixing techniques based on mechanical stirring which induces turbulence. Static mixers can be used to solve this mixing problem. In this paper, micromixers having geometries very close to those of conventional large-scale static mixers used in the chemical and food-processing industry are presented. Two kind of geometries have been studied. The first type of mixers is composed of a series of stationary rigid elements that form intersecting channels to split, rearrange and combine component streams. The second type of geometry is composed of a series of short helix elements arranged in pairs; each pair comprised of a right-handed and left-handed element arranged alternately in a pipe. Micromixers of both types have been designed by CAD and manufactured with the integral microstereolithography process, a new microfabrication technique that enables the manufacturing of complex, three-dimensional objects in polymers. The realized structures have been tested experimentally. Numerical simulations of the micromixers with the CFD program FluentTM have been performed to evaluate their mixing efficiency.

Although automatic machine translation (MT) of unconstrained text is beyond the state of the art today, the need for increased translator productivity is urgent. The PANI3LOSS system addresses this dilemma by integrating MT with machine-aided translation (MAT). The main measure of progress in the development of the PANGLOSS system is a gradual increase in the level of automation. The current PANGLOSS MT system typically generates sub-sentence-length units of the target text. Any remaining gaps are treated by lexicon lookup. A mixture of these two kinds of components is presented to the user using the CMAT (Component Machine-Aided Translation) editor, which was designed to facilitate the transformation of this output into a highquality text. An experiment evaluating the utility of the CMAT editor demonstrated its usefulness in this task, and provides useful guidance for further development.