A mathematical procedure using the Matlab® PDE toolbox to calculate the numerical constant appearing in the general Taylor-Aris expression for the dispersion in a laminar flow through open-tubular conduits with a variety of quasi-rectangular cross-sectional shapes is described. The procedure has been applied to assess the effect of some of the most frequently occurring etching imperfections (linear or curved tapering of the inter-pillar distance along the depth coordinate, occurrence of local notches) in etched pillar array columns. In addition, covering a broad range of possible geometries, a number of new shapes and optimal geometries to minimize the dispersion in open-tubular microchannels and pillar array columns have been proposed. Making a full shape-sensitivity study, it was also found that, whereas the proposed designs can theoretically reduce the dispersion up to a factor of 8, relatively small deviations from this ideal shape can however again dramatically increase the dispersion. Designers should therefore be very careful before implementing an optimized shape and should first aim at solving the etching imperfection problems.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.chroma.2014.09.009 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
A unified model for droplet receding contact angles on hydrophobic pillar, pore, and hollowed pillar arrays.
J Colloid Interface Sci
December 2024
Department of Mechanical Engineering (Robotics), Guangdong Technion - Israel Institute of Technology, Shantou, Guangdong 515063, China.
Hypothesis: Current models for receding contact angles of Cassie-Baxter state droplets on textured hydrophobic substrates are applicable only to a specific structural type, e.g., pillar (above which a droplet has isolated contact line and continuous liquid-vapor interface) or pore (continuous contact line and isolated liquid-vapor interface), signifying a lack of universality.
View Article and Find Full Text PDFUnderstanding the National Healthcare Ecosystem to Position Medical Affairs as a Strategic Element: Lessons Learned from AstraZeneca Spain.
Pharmaceut Med
December 2024
Medical Affairs Department, AstraZeneca Farmacéutica Spain, C. del Puerto de Somport 21-23, Fuencarral-El Pardo, 28050, Madrid, Spain.
Introduction: The rapidly evolving healthcare landscape has prompted Medical Affairs (MA) departments within pharmaceutical companies to transition from their traditional role as information providers to becoming strategic partners in the healthcare ecosystem. Responding to the increasing complexity of patient needs and stakeholder dynamics within Spain's national health system, this shift emphasizes the importance of aligning MA functions with broader healthcare goals. Effective transformation requires in-depth assessments of stakeholder trends and expectations.
View Article and Find Full Text PDFRealizing Square-Ordered Nanopillars with a 0.1-Tera-Density through a Superimposed Masking Strategy for Advanced Surface-Enhanced Raman Spectroscopy.
ACS Appl Mater Interfaces
December 2024
Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.
Article Synopsis
- Widespread interest in nanoscale pillar structures for optical devices faces challenges like high equipment costs and limited scalability due to traditional manufacturing methods.
- The study introduces a novel technique using thermally assisted nanotransfer printing to create highly uniform nanoscale pillar arrays, achieving an impressive density of 0.1 tera-pillars per square inch.
- These nanopillars are demonstrated as effective surface-enhanced Raman scattering sensors, providing consistent performance and sensitivity at very low concentrations while maintaining durability for multiple uses.
Observation of edge bound states in the continuum at truncated silicon pillar photonic crystal.
Nat Commun
December 2024
DTU Electro, Technical University of Denmark, Ørsteds Plads, Building 343, DK-2800, Kgs. Lyngby, Denmark.
Bound states in the continuum are optical modes with extremely high-quality factors and narrow resonances, which exist in the dispersion spectrum of the radiative region above the light line. A unique bound state in the continuum is supported at the edge of truncated photonic crystals, which is a type of a Fabry-Pérot type bound state in the continuum, but has never been observed in experiments. Here, we demonstrate the bound states in the continuum supported at the edge array of silicon (Si) pillars whose diameter is bigger than that of the rest of a Si-pillar two-dimensional photonic crystal.
View Article and Find Full Text PDFStatin-treated RBC dynamics in a microfluidic porous-like network.
Microvasc Res
November 2024
FluME, Department of Mechanical Engineering, University College London, London, UK; UCL Hawkes Institute, University College London, London, UK. Electronic address:
The impact of therapeutic interventions on red blood cell (RBC) deformability and microscale transport is investigated, using statins as an exemplar. Human RBCs were treated in vitro with two commonly prescribed statins, atorvastatin and rosuvastatin, at clinically relevant concentrations. Changes in RBC deformability were quantified using a microfluidic-based ektacytometer and expressed in terms of the elongation index.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!