Esmail A. Basheer ¹, Hayder A. Bari ¹

Affiliations
1 Centre of Excellence for Advanced Research in Fluid Flow (CARIFF) Universiti Malaysia Pahang, Gambang - 26300, Pahang,, MY

Abstract

Background/Objectives: The design and fabrication of Microfluidics-based electrochemical biosensor with high quality and the optimal effective surface area are of primary importance for more accurate result. The effects of the microelectrode size with variation in the microchannel size was investigated. Methods/Statistical Analysis: The effect of the microchannel size on the performance of the sensor was then investigated using cyclic voltammetry testing for different sizes of the fabricated channels (100, 400, 700 and 1000 μm) at electrode size of 100μm and 200μm. Findings: The electrokinetic properties of the microchannel were found to be affected by the size of both the microchannel and the electrode. The highest sensitivity of the sensor was reported at microchannel size of 700 and electrode size of 200μm. Application/Improvements: High accuracy and fast responding electrochemical biosensor are expected to be produced through the optimization of the microchannel size and the electrode surface area.

Keywords

Microfluidics, Electrochemical Biosensor, Microscope, Microchannel, Electrode.

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Sarmad k Fakhrulddin ¹, Hayder A. Bari ¹, Ahmed Z. Sulaiman ¹, Hind A. Rafeeq ²

Affiliations
1 Faculty of Chemical and Natural Resources Engineering, UniversityMalaysia Pahang, Gambang 26300, Pahang,, MY
2 Petroleum engineering department, Engineering College, University Kirkuk, 36001 Kirkuk, Kirkuk, Iraq;

Abstract

Objectives: Polyethylene Oxide (PEO) is one of the most effective drag reduction additives. However, it limits and degrades under high share stress. The improvement of its Drag Reduction (DR) efficiency and degradation resistant with the addition of cationic surfactant was investigated. Methods/Statistical Analysis: PEO at concentrations of 10 and 20 ppm were mixed with a different concentration of Hexadecyltrimethylammonium Chloride (HTAC). Capillary viscometer and Rotating Disk Apparatus (RDA) were used to measure the viscosity and the %DR, respectively. Findings: The results showed an improvement in both the DR ability and degradation resistance when the complex polymer-surfactant was used, compared to the pure polymer. The maximum DR was recorded as 36% at 10ppm and 42% at 20ppm PEO and 125ppm HTAC. This improvement was due to the interaction between the micelles and the polymer. Application/Improvements: This improvement will promote the use of PEO/HTAC mixture in higher share stress flow application.

Keywords

Drag Reduction, Degradation, Polymer-Surfactant, Rotating Disk Apparatus

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