| 1. |
- Berglund, Martin, 1985-, et al.
(författare)
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Extreme-temperature lab on a chip for optogalvanic spectroscopy of ultra small samples – key components and a first integration attempt
- 2016
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Ingår i: 27th Micromechanics And Microsystems Europe Workshop (MME 2016). - : Institute of Physics (IOP).
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Konferensbidrag (refereegranskat)abstract
- This is a short summary of the authors’ recent R&D on valves, combustors, plasma sources, and pressure and temperature sensors, realized in high-temperature co-fired ceramics, and an account for the first attempt to monolithically integrate them to form a lab on a chip for sample administration, preparation and analysis, as a stage in optogalvanic spectroscopy.
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| 2. |
- Klintberg, Lena, et al.
(författare)
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Partial least squares modelling of spectroscopic data from microplasma emissions for determination of CO2 concentration
- 2020
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Ingår i: Plasma Research Express. - : IOP Publishing. - 2516-1067. ; 2:4
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Tidskriftsartikel (refereegranskat)abstract
- The spectral emissions from a microplasma have been used to predict the CO2 concentration in gas samples covering a concentration range of 0%–100%. Different models based on partial least squares have been evaluated, comparing two different spectral pre-processing filters – multiplicative scatter correction (MSC) and standard normal variate correction (SNV) – and three different wavelength ranges. The models were compared with respect to accuracy, precision, stability and linearity. CO2 samples were mixed with either air or nitrogen. The choice of mixing gas influenced the predicted concentration and basing the models on data from only one mixing gas resulted in higher prediction power. Using air as mixing gas and SNV filtering resulted in a root mean square error of prediction (RMSEP) of 0.03 for an independent test dataset. This RMSEP was of the same range as the experimental error. On the other hand, the models with the best long term stability, reaching the lowest Allan variance, were based on observations with both mixing gases. Models based on MSC filtering generally had slightly higher RMSEP than those based on SNV filtering. Generally, the CO2 concentration could be accurately predicted in the concentration range of 5%–90%. For higher and lower concentrations, the models underestimated the CO2 concentration and were less accurate and precise. Basing the models on fewer wavelengths resulted in reduced linearity. The models were also evaluated by applying them for transcutaneous blood gas monitoring, where they helped to reveal new physiological information.
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| 3. |
- Nguyen, Hugo, 1955-, et al.
(författare)
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Material- and fabrication-governed performance of a tunnelling magnetometer
- 2010
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Ingår i: Advances in Natural Sciences. - : Institute of Physics (IOP). - 2043-6254 .- 2043-6262. ; 1:4, s. 045006-
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Tidskriftsartikel (refereegranskat)abstract
- Miniaturization of sensitive magnetic sensors for nano- and picosatellites has come to the point where the traditional sensors with magnetic coils soon can be replaced. Thin film technology offers the possibility of making extremely small magnetic field sensors that employ the effect of anisotropic, giant and tunneling magnetoresistance (AMR, GMR and TMR). In this paper, the development status of sensors based on microelectromechanical systems technology (MEMS), starting from a TMR layer structure is presented. The sensors have been successfully fabricated and integrated onto an electronic circuit designed for space application. The system as a whole, and the sensors in particular, have not only been characterized with respect to sensitivity, resolution, and noise level, but also to launch vibration and space radiation. The sensor performance and limitations are strongly dependent on the deposited materials, sensor design, and fabrication process. Since the sensor elements are small and sensitive (with lateral dimensions of some tens of micrometres, and resolution of 100 pT at frequencies of MHz), they are also promising for other MEMS applications.
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| 4. |
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| 5. |
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| 6. |
- Persson, Anders, 1982-, et al.
(författare)
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Disrupting Blood Gas Analysis, Path to Rapid, Gentle and Continuous Monitoring : DBGA
- 2020
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- For prematurely born children, yearly amounting to 15 million, monitoring of CO2 content in the blood is vital. Clinically, either ablood sample is taken, limiting the number of measurements and delaying the information, or a method detecting the gas escapingthrough the skin on heating it, is used. The latter poses severe risks of injury either by the heat itself or from skin rupturing onremoving the sensor. Here, a truly non-invasive concept has been fully prototyped and benchmarked. It allows for continuous, nonlagging,measurements of a quality seemingly outperforming state-of-the-art equipment, also on body parts previously considereddisqualified.
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| 7. |
- Persson, Anders, 1982-, et al.
(författare)
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Dynamic Behaviour and Conditioning Time of a Zirconia Flow Sensor for High-Temperature Applications
- 2016
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Ingår i: Sensors and Actuators A-Physical. - : Elsevier BV. - 0924-4247 .- 1873-3069. ; 251, s. 59-65
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Tidskriftsartikel (refereegranskat)abstract
- The temperature dependent ion conductivity of yttria stabilized zirconia (YSZ) can be used to create a miniaturized flow sensor using a calorimetric measurement scheme. Such a sensor is compatible with harsh environments, and can sustain temperatures of up to 1000 degrees C, although thermal crosstalk will limit its performance as the temperature rises. This paper investigates if the integration of thermal isolation in the form of sealed cavities can mitigate the detrimental effect of the thermal crosstalk, particularly by studying the conditioning time of the sensor to temperature changes. To this end, high temperature co-fired ceramic (HTCC) sensors were fabricated from tapes of 8 mol-% YSZ that were screen printed with platinum paste. Definition of channels and structures were made by milling the green tapes, and sacrificial inserts were placed in all cavities to give mechanical support during lamination and sintering. Cavities with widths of 240 mu m, 400 mu m and 560 mu m were investigated, and sensors without cavities were also made to serve as references. Additionally, two different positions of the sensor element with respect to the edge of the cavity (560 or 800 mu m) were investigated. The results showed that it was possible to improve the conditioning time of the sensor by up to five times by the use of isolating cavities, and that this improvement is translated into a reduction in rate-dependent hysteresis for measurements with long elapse times. The latter effect is most pronounced for the sensors with the largest cavities.
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| 8. |
- Persson, Anders, 1982-
(författare)
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Energy sources and energy harvesting for high-power pneumatic microsystems
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Pneumatic microsystems control fluid pressure for various tasks like soft robotics and tactile displays. This study shifts focus to system integration, often overlooked in research when aspects like total size, mass, and power consumption are neglected. The study explores energy source integration efficiency and proposes solutions through both a literature review that identifies key parameters for potential energy sources and microsystem applications, and experimental investigations where mechanical transmission is used to adapt energy sources to application-based requirements. Comparative analysis categorizes energy sources and assesses their performance and their relation to fundamental limits like the average power exerted by the human body. Mechanical transmission's role in optimizing energy source-application compatibility is found promising, at least for moderate optimization. To conclude, bypassing energy transduction enhances energy harvesting efficiency. Mechanical-to-pneumatic systems are efficient, and mechanical transmission optimizes source-application matching. Human body energy remains a critical constraint. For high energy demands, portable batteries become essential.
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| 9. |
- Persson, Anders, 1982-
(författare)
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EU Diplomacy and the Israeli–Arab Conflict, 1967–2019
- 2020. - 1
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Bok (refereegranskat)abstract
- Nearly 50 years since the European Foreign Ministers issued their first declaration on the conflict between Israel and Palestine in 1971, the EU continues to have close political and economic ties with the region. Based exclusively on primary sources, this study offers an up-to-date overview of EU’s involvement in the Israeli-Arab conflict since 1967. It utilises an innovative methodology to analyse keyword frequency in a sample of more than 2300 declarations and statements published in the Bulletin of the European Communities/European Union (1967–2009) as well as council reports and press interviews (2009–2018) to uncover broad patterns for qualitative analysis. The outcomes suggest that the Israeli-Arab conflict is more important to the EU than any other conflict, having been key to shaping EU’s foreign policy overall.
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