Large scale micro-photometry for high resolution pH-characterization during electro-osmotic pumping and modular micro-swimming
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| Anzahl der Teile | 40 | |
| Autor | 0000-0001-7791-3914 (ORCID) | |
| Lizenz | CC-Namensnennung 3.0 Unported: Sie dürfen das Werk bzw. den Inhalt zu jedem legalen Zweck nutzen, verändern und in unveränderter oder veränderter Form vervielfältigen, verbreiten und öffentlich zugänglich machen, sofern Sie den Namen des Autors/Rechteinhabers in der von ihm festgelegten Weise nennen. | |
| Identifikatoren | 10.5446/38419 (DOI) | |
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33
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Maßstab <Messtechnik>GleitlagerVideotechnikComputeranimation
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ÜberlagerungsempfängerBasis <Elektrotechnik>RaumauflösungMaßstab <Messtechnik>BrechzahlFörderleistungPräzessionMessungBlatt <Papier>DruckgradientTonhöheFehlprägungEisHerbstSensorComputeranimation
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SchnittmusterOptisches FilterFarbcodierungIntensitätsverteilungLadungsgekoppeltes BauelementPACMaßstab <Messtechnik>IntensitätsverteilungSchnittmusterBeleuchtungsstärkeKaliber <Walzwerk>Optische DichteBuntheitChannelingBrechzahlSensorBildsensorEnergielückeMessungLichtPhasengesteuerte AntennengruppeBahnelementKardierenTrenntechnikKonzentrator <Nachrichtentechnik>Computeranimation
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Kalibrieren <Fertigungstechnik>Maßstab <Messtechnik>ChannelingOptische DichtePufferlagerUnterwasserfahrzeugKaliber <Walzwerk>Masse <Physik>PagerDiagramm
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Osmotischer DruckSpeckle-InterferometrieWärmeaustauscherPumpen <Laser>FörderleistungIonHammerHandbuchbindereiTunerWerkzeugHerbstComputeranimationDiagramm
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Schwimmer <Technik>Front <Meteorologie>ADSLSchwimmer <Technik>FärberModell <Gießerei>NiederschlagsmengeComputeranimationDiagramm
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Schwimmer <Technik>MessungMitlauffilterVideotechnikGleichstromAnstellwinkelSchwimmer <Technik>Computeranimation
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Schwimmer <Technik>Schwimmer <Technik>AnstellwinkelMitlauffilterDruckgradientVideotechnikGleichstromComputeranimationDiagramm
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Schwimmer <Technik>UnterwasserfahrzeugComputeranimationDiagramm
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Schwimmer <Technik>AmplitudeGleichstromAvro ArrowComputeranimation
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Schwimmer <Technik>GleichstromAmplitudeComputeranimation
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Schwimmer <Technik>KlangeffektPatrone <Munition>IrrlichtKernstrahlungZentralsternElektrische StromdichteComputeranimation
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Schwimmer <Technik>KlangeffektComputeranimation
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Schwimmer <Technik>Maßstab <Messtechnik>ADSLTeilchenSchwimmer <Technik>Schwache LokalisationNeutronenaktivierungBlatt <Papier>MessungDruckgradientGruppenlaufzeitCocktailparty-EffektBrennstoffTürglockePagerComputeranimation
03:56
Cocktailparty-EffektBlatt <Papier>
Transkript: Englisch(automatisch erzeugt)
00:05
Hello, in this study, we developed a large-scale photometry method for pH detection, which has potential implications in a large variety of complex flow situations involving pH gradients. The motivation comes from the disadvantage of pH measurement using indicator paper or pH meter,
00:25
which either have poor quantitative precession or no spatial resolution. Our method utilizes low-cost lab setup, namely a low-resolution microscope, a DLSR, and a laptop for data analysis.
00:43
The camera sensor is composed of individual pixels, each made sensitive for light in red, green, or blue band by a suitable filter. Color discrimination on the sensor uses a bio-pattern. Using a home-written pattern script, we separate the three color channels into three separate arrays.
01:04
The absorbance or light transmitting through a sample is given by the Beer-Lambert law. According to the equation, the absorbance ratio of two colors equals the ratio of attenuation coefficients, which renders the calibration and measurements independent of indicator concentration, sample thickness, and illumination intensity.
01:27
We calibrate the ratio over the absorbance of two different channels to pH using buffer solution of different pH. Choosing a suitable indicator-fluid mixture, the ratio of attenuation coefficients monotonically decreases with increase in pH.
01:43
Then, we interpolate the measured data points for the calibration curve. The performance of the method was first tested on an electro-automotive pump based on an ion exchange-induced electro-automotive flow.
02:01
In the center, you see the ion exchanger. Now it starts exchange. Here we reach a pH resolution of 0.02 on averaging readily over 20 subsequent images and a time resolution of 4 seconds.
02:24
For a more complex modular swimming situation, we also test the performance under ideal conditions, that is with optical impurities from the precipities of dye and passive cargo. Modular swimmer is accompanied with an asymmetric pH gradient, which is deepened in the front and extended in the pH range in the back of the swimmer.
02:47
Due to the asymmetry of the gradient, we use line analysis for select angles with respect to the swimming direction. Under this non-ideal preparation condition, the curves are noisy with several statistically distributed and uncorrelated peaks along the radial direction.
03:05
However, the data quality from this dirty case is already sufficient to obtain a good qualitative impression on the characteristic effects. Our method can also be applied to measure the pH gradients generated by other fratic swimmers,
03:23
for example, the large variety of catalytic generous particles or for asymmetric particles in AC electric fields. With enough resolution, our method should further allow local pH measurement along the surfaces of active particles. Thus, it could be used to test the pH taxes of biohybrid macrosystems and artificial swimmers.
03:46
Furthermore, it may be interesting to apply our method to the complex collective behavior of groups of fratic microswimmers. For more details, please read our paper. Thanks for your attention.
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