Heidi Ottevaere

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Experimental and theoretical proof is provided for the fact that a microfabricated packed bed column, which is uniformly filled with radially elongated pillars (REPs), can produce the same separation performance as nonpacked, open-tubular columns. These are generally recognized as the best possible chromatographic column format, offering the highest(More)
In conventional multichannel imaging systems, all channels have similar imaging properties [field-of-view (FOV) and angular resolution]. In our approach, channels are designed to have different imaging properties which add multiresolution capability to the system. We have experimentally demonstrated, for the first time to our knowledge, a three-channel(More)
The individual factors that determine the kinetic performance (B- and C-term band broadening and bed permeability Kv) of radially elongated pillar (REP) columns are studied. To this end, columns with REPs having 4 different aspect ratios (AR=9, 12, 15, 20) were characterized experimentally and by means of numerical simulations. A tortuosity and retention(More)
We report a novel process technology of hemispherical shaped microlenses, using isotropic wet etching of silicon in an acid solution to produce the microlenses molds. Governed by process parameters such as temperature and etchant concentration, the isotropic wet etching is controlled to minimize various defects that appear during the molding creation. From(More)
Because of its high price, extra virgin olive oil is frequently targeted for adulteration with lower quality oils. This paper presents an innovative optical technique capable of quantifying and discriminating the adulteration of extra virgin olive oil caused by lower-grade olive oils. An original set-up for diffuse-light absorption spectroscopy in the wide(More)
Doughnut shaped hybridization patterns on DNA microarrays are mainly allocated to spotting or drying artifacts. The present study reports on results obtained from four different approaches that when combined generate a better view on the occurrence of these patterns. This study points out that doughnuts are not only formed during the spotting and drying(More)
Microstructured optical products are becoming more widespread due to advances in manufacturing. Many of these structures contain faceted surfaces with steep slopes. Adequate metrology for such surfaces is lacking. We describe an interferometric technique that combines plane wave illumination with an index matching liquid to achieve high quality, high speed(More)
We report on the possibility to realize submicrometer plate heights using chromatographic pillar array columns filled with radially elongated diamond-shaped pillars, even when using a relatively large interpillar distance (2.5 μm) and axial pillar width (5 μm). It is demonstrated that the use of high aspect ratio radially elongated pillars which are 15(More)
We report on a series of preliminary experiments investigating the applicability of a novel method for the size separation of nano- and microsized particles and cells. The working principle is based on the application of a shear-driven flow through stepwise tapered micro- or nanochannels. Size separations of mixtures of 0.5 and 1.0 microm carboxylated(More)