Articles | Volume 7, issue 1
https://doi.org/10.5194/jsss-7-31-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/jsss-7-31-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Regular research article
| 
01 Feb 2018
Regular research article |
| 01 Feb 2018
| 01 Feb 2018
Nanocomposite sensors of propylene glycol, dimethylformamide and formaldehyde vapors
Zaven Adamyan
Department of Physics of Semiconductors and Microelectronics, Center
of Semiconductor Devices and Nanotechnologies, Yerevan State University, 1
A. Manoukian, 0025 Yerevan, Armenia
Artak Sayunts
CORRESPONDING AUTHOR
Department of Physics of Semiconductors and Microelectronics, Center
of Semiconductor Devices and Nanotechnologies, Yerevan State University, 1
A. Manoukian, 0025 Yerevan, Armenia
Vladimir Aroutiounian
Department of Physics of Semiconductors and Microelectronics, Center
of Semiconductor Devices and Nanotechnologies, Yerevan State University, 1
A. Manoukian, 0025 Yerevan, Armenia
Emma Khachaturyan
Department of Physics of Semiconductors and Microelectronics, Center
of Semiconductor Devices and Nanotechnologies, Yerevan State University, 1
A. Manoukian, 0025 Yerevan, Armenia
Martin Vrnata
Department of Physics and Measurement Technology, University of Chemistry and Technology, Technická 5, 166 28 Prague 6, Czech Republic
Přemysl Fitl
Department of Physics and Measurement Technology, University of Chemistry and Technology, Technická 5, 166 28 Prague 6, Czech Republic
Jan Vlček
Department of Physics and Measurement Technology, University of Chemistry and Technology, Technická 5, 166 28 Prague 6, Czech Republic
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Vladimir Aroutiounian, Valeri Arakelyan, Mikayel Aleksanyan, Gohar Shahnazaryan, Petr Kacer, Pavel Picha, Jiri Kovarik, Jakub Pekarek, and Berndt Joost
J. Sens. Sens. Syst., 7, 281–288, https://doi.org/10.5194/jsss-7-281-2018, https://doi.org/10.5194/jsss-7-281-2018, 2018
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Some results of the solid-state hydrogen peroxide vapor sensors made from semiconductor doped metal oxide nanostructured films have been presented during the international conference in Nuremberg. In this paper the extended version of our investigations of the detectors of hydrogen peroxide vapors are presented. The prepared sensors exhibit a response to very low concentration of hydrogen peroxide vapors. These detectors can be used in medicine, pharmacology, food and the textile industry.
V. G. Harutyunyan, K. M. Gambaryan, V. M. Aroutiounian, and I. G. Harutyunyan
J. Sens. Sens. Syst., 4, 249–253, https://doi.org/10.5194/jsss-4-249-2015, https://doi.org/10.5194/jsss-4-249-2015, 2015
Related subject area
Sensor principles and phenomena: Chemical and biochemical sensors
Development of electrochemical sensors based on silver nanoparticles electrodeposited on gold screen-printed electrodes: application to nitrate trace analysis in water
Chemical hydrogel sensors based on the bimorph effect with short response time
Design of a dual electrochemical quartz crystal microbalance with dissipation monitoring
Surface plasmon assisted toxic chemical NO2 gas sensor by Au ∕ ZnO functional thin films
Studies on porosity in poly(N-isopropylacrylamide) hydrogels for fast-responsive piezoresistive microsensors
Ceramic multilayer technology as a platform for miniaturized sensor arrays for water analysis
Glass electrode half-cells for measuring unified pH in ethanol–water mixtures
Cyclic and square-wave voltammetry for selective simultaneous NO and O2 gas detection by means of solid electrolyte sensors
Multi-gas sensor to detect simultaneously nitrogen oxides and oxygen
Influence of Pt paste and the firing temperature of screen-printed electrodes on the NO detection by pulsed polarization
Siloxane treatment of metal oxide semiconductor gas sensors in temperature-cycled operation – sensitivity and selectivity
Determination of the mixing ratio of a flowing gas mixture with self-actuated microcantilevers
Enabling a new method of dynamic field-effect gas sensor operation through lithium-doped tungsten oxide
Optical and impedimetric study of genetically modified cells for diclofenac sensing
Novel radio-frequency-based gas sensor with integrated heater
Highly sensitive coulometric titration of oxygen for the characterization of solid materials at elevated temperatures
Trace determination of cadmium content in Malaysian herbs using graphene–ionic liquid-modified screen-printed carbon electrodes
Novel method for the detection of short trace gas pulses with metal oxide semiconductor gas sensors
A portable sensor system for bacterial concentration monitoring in metalworking fluids
Thin-film SnO2 and ZnO detectors of hydrogen peroxide vapors
Combined resistive and thermoelectric oxygen sensor with almost temperature-independent characteristics
Hydrogel-based piezoresistive sensor for the detection of ethanol
High-resolution ultrasonic spectroscopy
Design and evaluation of split-ring resonators for aptamer-based biosensors
Simulation of a thermoelectric gas sensor that determines hydrocarbon concentrations in exhausts and the light-off temperature of catalyst materials
Electron capture detector based on a non-radioactive electron source: operating parameters vs. analytical performance
Electrical impedance spectroscopy (EIS) for biological analysis and food characterization: a review
A DNA biosensor for molecular diagnosis of Aeromonas hydrophila using zinc sulfide nanospheres
H2S dosimeter with controllable percolation threshold based on semi-conducting copper oxide thin films
The concept of thin film bulk acoustic resonators as selective CO2 gas sensors
Biochemical piezoresistive sensors based on hydrogels for biotechnology and medical applications
Highly selective solid electrolyte sensor for the analysis of gaseous mixtures
Gas sensors based on plasma-electrochemically oxidized titanium foils
First steps to develop a sensor for a Tian–Calvet calorimeter with increased sensitivity
Selective detection of naphthalene with nanostructured WO3 gas sensors prepared by pulsed laser deposition
Flexible free-standing SU-8 microfluidic impedance spectroscopy sensor for 3-D molded interconnect devices application
Paradigm change in hydrogel sensor manufacturing: from recipe-driven to specification-driven process optimization
Platform to develop exhaust gas sensors manufactured by glass-solder-supported joining of sintered yttria-stabilized zirconia
Influence of operation temperature variations on NO measurements in low concentrations when applying the pulsed polarization technique to thimble-type lambda probes
Self-sufficient sensor for oxygen detection in packaging via radio-frequency identification
Influence of the substrate on the overall sensor impedance of planar H2 sensors involving TiO2–SnO2 interfaces
Defects and gas sensing properties of carbon nanotube-based devices
Development of a capacitive chemical sensor based on Co(II)-phthalocyanine acrylate-polymer/HfO2/SiO2/Si for detection of perchlorate
Room temperature carbon nanotube based sensor for carbon monoxide detection
Compensation for the influence of temperature and humidity on oxygen diffusion in a reactive polymer matrix
Devices based on series-connected Schottky junctions and β-Ga2O3/SiC heterojunctions characterized as hydrogen sensors
A simple method to recover the graphene-based chemi-resistor signal
Electrochemical analysis of water and suds by impedance spectroscopy and cyclic voltammetry
Overview on conductometric solid-state gas dosimeters
Gas identification based on bias induced hysteresis of a gas-sensitive SiC field effect transistor
Najib Ben Messaoud, Marília Barreiros dos Santos, Begoña Espiña, and Raquel Barbosa Queirós
J. Sens. Sens. Syst., 13, 135–145, https://doi.org/10.5194/jsss-13-135-2024, https://doi.org/10.5194/jsss-13-135-2024, 2024
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High levels of nitrate can cause negative effects on aquatic plants, fishes and human health. A simple, reusable and sensitive electrochemical sensor based on silver nanoparticles with a modified gold screen-printed electrode has been developed for the detection of nitrate in water. The sensor exhibited good performances such as high sensitivity, reproducibility, repeatability and selectivity. The proposed approach was successfully used to determine nitrate in freshwater.
Stefan Schreiber, Nadja Steinke, and Gerald Gerlach
J. Sens. Sens. Syst., 12, 141–146, https://doi.org/10.5194/jsss-12-141-2023, https://doi.org/10.5194/jsss-12-141-2023, 2023
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We have managed to reduce the measuring time of previously common hydrogel-based sensors from a few minutes to a few seconds. For this, the arrangement of the hydrogel in the sensor was changed so that the volume of the hydrogel could be reduced. The biggest challenge, apart from generating a very thin pattern, was to firmly bond the hydrogel to a silicon surface. This was to ensure that the resulting forces of the bimorph effect can be absorbed.
Rafael Ecker, Nikolaus Doppelhammer, Bernhard Jakoby, and Erwin Konrad Reichel
J. Sens. Sens. Syst., 11, 21–28, https://doi.org/10.5194/jsss-11-21-2022, https://doi.org/10.5194/jsss-11-21-2022, 2022
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A setup for the characterization of liquids with the perspective of monitoring crystallization processes is presented. The novelty of this setup is the realization of viscosity and conductivity measurements using two quartz crystal microbalances. Additionally, there is the possibility to apply an electric field through the sample, enabling the manipulation of charged particles. The results show that the measured values are in reasonable agreement with values from the literature or standards.
Ravinder Gaur, Himanshu Mohan Padhy, and Manikandan Elayaperumal
J. Sens. Sens. Syst., 10, 163–169, https://doi.org/10.5194/jsss-10-163-2021, https://doi.org/10.5194/jsss-10-163-2021, 2021
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We propose a surface plasmon resonance (SPR) sensor based on a ZnO / Au hybrid thin-film material structure and experimentally investigate its sensitivity improvement. The Kretschmann-based SPR sensor utilizes ZnO thin films and nanostructures for performance enhancement. The advancement in SPR technology relies on a low-cost, high-sensitivity, and high-selectivity sensor. Metal oxide (MO) has been incorporated into the SPR sensor to be used for detection of biological and chemical compounds.
Daniela Franke and Gerald Gerlach
J. Sens. Sens. Syst., 10, 93–100, https://doi.org/10.5194/jsss-10-93-2021, https://doi.org/10.5194/jsss-10-93-2021, 2021
Claudia Feller and Uwe Partsch
J. Sens. Sens. Syst., 10, 83–91, https://doi.org/10.5194/jsss-10-83-2021, https://doi.org/10.5194/jsss-10-83-2021, 2021
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Ion-selective electrodes have been proven useful in water analysis. They are usually used as single-rod measuring chains in different designs, which are manufactured using precision mechanical manufacturing and assembling technologies. The paper describes a microsystem technology approach for the fabrication of miniaturized electrochemical sensors. Design, manufacture, and performance of the novel ceramic multilayer-based sensor array are presented in the paper using various examples.
Agnes Heering, Frank Bastkowski, and Steffen Seitz
J. Sens. Sens. Syst., 9, 383–389, https://doi.org/10.5194/jsss-9-383-2020, https://doi.org/10.5194/jsss-9-383-2020, 2020
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The new concept of a unified pH scale can be used to compare acidities of different kinds of solvents and their mixtures. The aim of the work was to investigate the robustness of the measurement method with four commercially available glass electrodes for non-aqueous media in comparison with the rather specific type of cell used so far for this measurement. The measurement results in aqueous mixtures of ethanol show good agreement.
Anastasiya Ruchets, Nils Donker, Jens Zosel, Daniela Schönauer-Kamin, Ralf Moos, Ulrich Guth, and Michael Mertig
J. Sens. Sens. Syst., 9, 355–362, https://doi.org/10.5194/jsss-9-355-2020, https://doi.org/10.5194/jsss-9-355-2020, 2020
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A commercial solid electrolyte gas sensor of the type "Pt|YSZ|Pt, air" based on yttria-stabilized zirconia for colorimetric oxygen detection was operated in optimized dynamic electrochemical modes. Cyclic voltammetry and square-wave voltammetry were used for the detection of NO and O2 in N2 in the temperature range between 550 and 750 °C. Due to the differences of electrode kinetics of the single components it is possible to detect these redox active gases selectively and quasi-simultaneously.
Julia Herrmann, Gunter Hagen, Jaroslaw Kita, Frank Noack, Dirk Bleicker, and Ralf Moos
J. Sens. Sens. Syst., 9, 327–335, https://doi.org/10.5194/jsss-9-327-2020, https://doi.org/10.5194/jsss-9-327-2020, 2020
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In this contribution, an inexpensive and robust impedimetric NOx sensor is presented. The impedance of a functional thick film depends selectively on the NOx concentration in the exhaust but shows a dependency on the oxygen concentration. Therefore, an additional temperature-independent resistive oxygen sensor structure was integrated on the same sensor platform. It serves not only to determine the oxygen concentration in the exhaust, but also to correct the oxygen dependency of the NOx sensor.
Nils Donker, Anastasiya Ruchets, Daniela Schönauer-Kamin, Jens Zosel, Ulrich Guth, and Ralf Moos
J. Sens. Sens. Syst., 9, 293–300, https://doi.org/10.5194/jsss-9-293-2020, https://doi.org/10.5194/jsss-9-293-2020, 2020
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Symmetrical Pt | YSZ | Pt–NO gas sensors were produced with frit-containing and fritless Pt electrodes and fired between 950 and 1300 °C. The sensors were operated by pulsed polarization. With fritless pastes, the sensors responded significantly higher. The firing temperature affects the sensitivity only slightly. The low NO sensitivity of the frit-containing electrodes was attributed to a blocking effect at the triple-phase boundaries that inhibits the oxygen transport through the sensor.
Caroline Schultealbert, Iklim Uzun, Tobias Baur, Tilman Sauerwald, and Andreas Schütze
J. Sens. Sens. Syst., 9, 283–292, https://doi.org/10.5194/jsss-9-283-2020, https://doi.org/10.5194/jsss-9-283-2020, 2020
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We present a work on gas sensors that can for example be used for the assessment of indoor air quality. These sensors suffer from deterioration by siloxanes, so we investigated these effects by a distinct operation mode and exposition to this gas that allows us to interpret different reactions on the sensor surface. We found that all processes on the sensor surface are slowed down by this treatment and a self-compensation by the evaluation of oxygen adsorption processes is likely to be found.
Jaqueline Stauffenberg, Steve Durstewitz, Martin Hofmann, Tzvetan Ivanov, Mathias Holz, Waleed Ehrhardt, Wolf-Ulrich Riegel, Jens-Peter Zöllner, Eberhard Manske, and Ivo Rangelow
J. Sens. Sens. Syst., 9, 71–78, https://doi.org/10.5194/jsss-9-71-2020, https://doi.org/10.5194/jsss-9-71-2020, 2020
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In this work, a self-actuated microcantilever is used as a flow sensor. Its resonance frequency, resonance amplitude and static deflection are measured. Most conventional flow sensors are often only calibrated for one type of gas and allow an analysis of gas mixtures only with increased effort. The work examines whether the volumetric flow and the mixing ratio of a binary gas mixture are possible simultaneously from these measured variables.
Marius Rodner, Manuel Bastuck, Andreas Schütze, Mike Andersson, Joni Huotari, Jarkko Puustinen, Jyrki Lappalainen, and Tilman Sauerwald
J. Sens. Sens. Syst., 8, 261–267, https://doi.org/10.5194/jsss-8-261-2019, https://doi.org/10.5194/jsss-8-261-2019, 2019
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To fulfil today's requirements, gas sensors have to become more and more sensitive and selective. In this work, we present a novel method to significantly enhance the effect of gate bias on the response of a SiC field-effect transistor by placing a lithium-doped tungsten oxide film beneath the gate. This enhancement, compared to undoped samples, opens new perspectives for static and transient signal generation, e.g. gate bias-cycled operation, and, thus, increasing sensitivity and selectivity.
Margarita Guenther, Falko Altenkirch, Kai Ostermann, Gerhard Rödel, Ingo Tobehn-Steinhäuser, Steffen Herbst, Stefan Görlandt, and Gerald Gerlach
J. Sens. Sens. Syst., 8, 215–222, https://doi.org/10.5194/jsss-8-215-2019, https://doi.org/10.5194/jsss-8-215-2019, 2019
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In this work, genetically modified cells of the yeast Saccharomyces cerevisiae BY4741 were confined in a four-chamber microfluidic cell, providing an optical monitoring of the cell behaviour and their supply with the nutrients. The measurements of the time-dependent fluorescence intensity were performed with different concentrations of the drug diclofenac, and the sensitivity of yeast cells to diclofenac was demonstrated. Cell viability was monitored by simultaneous impedance recording.
Stefanie Walter, Andreas Bogner, Gunter Hagen, and Ralf Moos
J. Sens. Sens. Syst., 8, 49–56, https://doi.org/10.5194/jsss-8-49-2019, https://doi.org/10.5194/jsss-8-49-2019, 2019
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A planar resonant radio-frequency gas sensor was equipped with an integrated heater. By simulative geometry optimization it now can be operated up to 700 °C. Sensitive materials with gas-dependent dielectric properties at higher temperatures can now be used. By coating the sensor with zeolite, ammonia could be detected. Depending on the working temperature, the sensor returns either a dosimeter signal (low temperatures) or a gas-concentration-dependent radio-frequency signal (high temperatures).
Alexander Herms, Jingying Yao, Jens Zosel, Vladimir Vashook, Wolfram Oelßner, and Michael Mertig
J. Sens. Sens. Syst., 7, 621–625, https://doi.org/10.5194/jsss-7-621-2018, https://doi.org/10.5194/jsss-7-621-2018, 2018
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For the understanding of new materials, especially oxides, oxygen exchange of such materials and its consequences for their properties are of high interest. For this purpose a new setup for oxygen solid electrolyte coulometry with electrochemical cells made of yttria-stabilized zirconia (YSZ) is presented. It could be shown that this setup enables the measurement of exchanged oxygen from the picomol up to the higher nanomol range with a precision which was not achieved so far.
Muhammad Syafiq Nordin, Yusairie Mohd, Noor Fitrah Abu Bakar, and Zainiharyati Mohd Zain
J. Sens. Sens. Syst., 7, 481–487, https://doi.org/10.5194/jsss-7-481-2018, https://doi.org/10.5194/jsss-7-481-2018, 2018
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Cadmium is one of heavy metals that can cause serious health complications if humans are excessively exposed. This research was conducted to detect the amount of cadmium inside herbal plants using a new sensor modified with graphene and ionic liquid. The amount of cadmium inside herbs A, D, M and C were 0.0035, 0.0237, 0.0267 and 0.0251 milligrams/litre, respectively. The results showed that the herbs were safe to be consumed. The developed sensor was comparable to existing detection methods.
Tobias Baur, Caroline Schultealbert, Andreas Schütze, and Tilman Sauerwald
J. Sens. Sens. Syst., 7, 411–419, https://doi.org/10.5194/jsss-7-411-2018, https://doi.org/10.5194/jsss-7-411-2018, 2018
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A novel method for the detection of short pulses of gas at very low concentrations is presented. Applying the method to a doped SnO2 detector, gas pulses down to a dosage of 1 ppb times seconds can be detected. The gas transport inside the detector is simulated using the finite element method (FEM) to optimize the gas transport and to keep response and recovery time as short as possible. With this approach, we have demonstrated a detection limit for ethanol below 47 fg.
Marco Grossi, Carola Parolin, Beatrice Vitali, and Bruno Riccò
J. Sens. Sens. Syst., 7, 349–357, https://doi.org/10.5194/jsss-7-349-2018, https://doi.org/10.5194/jsss-7-349-2018, 2018
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The paper presents a portable sensor system that measures the bacterial concentration in metalworking fluids (MWFs) exploiting impedance microbiology. Good agreement has been found between the system response and that of the reference plate count technique (PCT). The proposed system allows automated bacterial concentration measurements with shorter response times than the PCT (4 to 24 h vs. 24 to 72 h) and is suitable for in-the-field MWF monitoring.
Vladimir Aroutiounian, Valeri Arakelyan, Mikayel Aleksanyan, Gohar Shahnazaryan, Petr Kacer, Pavel Picha, Jiri Kovarik, Jakub Pekarek, and Berndt Joost
J. Sens. Sens. Syst., 7, 281–288, https://doi.org/10.5194/jsss-7-281-2018, https://doi.org/10.5194/jsss-7-281-2018, 2018
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Some results of the solid-state hydrogen peroxide vapor sensors made from semiconductor doped metal oxide nanostructured films have been presented during the international conference in Nuremberg. In this paper the extended version of our investigations of the detectors of hydrogen peroxide vapors are presented. The prepared sensors exhibit a response to very low concentration of hydrogen peroxide vapors. These detectors can be used in medicine, pharmacology, food and the textile industry.
Murat Bektas, Thomas Stöcker, Angelika Mergner, Gunter Hagen, and Ralf Moos
J. Sens. Sens. Syst., 7, 289–297, https://doi.org/10.5194/jsss-7-289-2018, https://doi.org/10.5194/jsss-7-289-2018, 2018
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We prepared BaFe(1-x)-0.01Al0.01TaxO3-δ (BFATx) thick films with x between 0.1 and 0.4 at room temperature using the aerosol deposition method and we measured Seebeck coefficients and conductivities between 600 and 800 °C at different oxygen concentrations. Deposited on a transducer that includes a heater, equipotential layers, and electrode structures, a dual thermoelectric–resistive oxygen sensor with almost temperature-independent characteristics of both measurands was realized using BFAT30.
Jan Erfkamp, Margarita Guenther, and Gerald Gerlach
J. Sens. Sens. Syst., 7, 219–226, https://doi.org/10.5194/jsss-7-219-2018, https://doi.org/10.5194/jsss-7-219-2018, 2018
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We describe a low-cost sensor for the detection of ethanol in alcoholic beverages. The reversible swelling of alcohol-sensitive hydrogels depends on the ethanol concentration. The resulting swelling pressure was detected via piezoresistive sensors. We have tested the swelling properties of the hydrogel (e.g. swelling kinetics, selectivity to other alcohols). Furthermore, the first sensor set-ups were tested and the reversibility of the hydrogel-based piezoresistive sensor was demonstrated.
Vitaly Buckin
J. Sens. Sens. Syst., 7, 207–217, https://doi.org/10.5194/jsss-7-207-2018, https://doi.org/10.5194/jsss-7-207-2018, 2018
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The paper reviews the principles and applications of high-resolution ultrasonic spectroscopy in real-time, non-destructive analysis of molecular transformations, including transitions in polymers, ligand binding, self-assembly, crystallisation, gelation, phase diagrams, monitoring of chemical and biochemical reactions. High precision and useful capabilities of this technique enable its application in a broad range of systems, where other methods often fail or have high analytical cost.
Tobias Reinecke, Johanna-Gabriela Walter, Tim Kobelt, André Ahrens, Thomas Scheper, and Stefan Zimmermann
J. Sens. Sens. Syst., 7, 101–111, https://doi.org/10.5194/jsss-7-101-2018, https://doi.org/10.5194/jsss-7-101-2018, 2018
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A systematic investigation of a split-ring resonator for application as a biosensor is presented. The parameters responsible for the sensitivity of the setup were determined using a new approach to determine the resonance frequency depending on the relative permittivity of the sample. Based on these parameters, the resonator structure was optimized. Subsequently, a split-ring resonator was functionalized with aptamers and a selective detection of CRP could be shown.
Thomas Ritter, Sven Wiegärtner, Gunter Hagen, and Ralf Moos
J. Sens. Sens. Syst., 6, 395–405, https://doi.org/10.5194/jsss-6-395-2017, https://doi.org/10.5194/jsss-6-395-2017, 2017
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A planar thermoelectric gas sensor is modeled. By coupling all influences (fluid flow, gas diffusion, heat transfer, chemical reactions, and electrical properties) a model was set up that mirrors the sensor behavior precisely, as the comparison with experimental data shows. The coupling of 3-D and 1-D geometry enables to calculate the temperature distribution, fluid flow, and the gas concentration distribution in the 3-D model, while the chemical reactions are very accurately calculated in 1-D.
Erik Bunert, Ansgar T. Kirk, Jens Oermann, and Stefan Zimmermann
J. Sens. Sens. Syst., 6, 381–387, https://doi.org/10.5194/jsss-6-381-2017, https://doi.org/10.5194/jsss-6-381-2017, 2017
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Electron capture detectors (ECDs) are widely used for the detection of electron affine substances such as pesticides or chlorofluorocarbons. In this work we present a new non-radioactive ECD and investigate the analytical performance depending on the operating parameters. We achieved limits of detection for 1,1,2-trichloroethane and sevoflurane, which are comparable to radioactive ECDs. Furthermore, a pulsed collector voltage mode was implemented, leading to an extended linear range.
Marco Grossi and Bruno Riccò
J. Sens. Sens. Syst., 6, 303–325, https://doi.org/10.5194/jsss-6-303-2017, https://doi.org/10.5194/jsss-6-303-2017, 2017
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Electrical impedance spectroscopy, in which a sine-wave test voltage or current is applied to the sample under test to measure its impedance over a suitable frequency range, is a powerful technique to investigate the electrical properties of a large variety of materials. This paper presents an updated review of EIS main applications such as measure of bacterial concentration, analysis of human body composition and characterization of food products, as well as other non-biological applications.
Masoud Negahdary, Mahnaz Jafarzadeh, Roya Rahimzadeh, Ghasem Rahimi, and Hamideh Dehghani
J. Sens. Sens. Syst., 6, 259–267, https://doi.org/10.5194/jsss-6-259-2017, https://doi.org/10.5194/jsss-6-259-2017, 2017
Christoph Seitz, Giuliana Beck, Jörg Hennemann, Christian Kandzia, Karl P. Hering, Angelika Polity, Peter J. Klar, Andrej Paul, Thorsten Wagner, Stefanie Russ, and Bernd M. Smarsly
J. Sens. Sens. Syst., 6, 163–170, https://doi.org/10.5194/jsss-6-163-2017, https://doi.org/10.5194/jsss-6-163-2017, 2017
Romy Hoffmann, Matthias Schreiter, and Johannes Heitmann
J. Sens. Sens. Syst., 6, 87–96, https://doi.org/10.5194/jsss-6-87-2017, https://doi.org/10.5194/jsss-6-87-2017, 2017
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Carbon dioxide is a main greenhouse gas and a gas that well-represents air quality. Therefore, it is important to monitor the CO2 concentration in air. Creating an affordable and reliable CO2 sensor is the purpose of this paper. Using a mass-sensitive acoustic sensor (FBAR) we can detect increasing CO2 concentration by a mass increase on the sensor surface. As humidity changes often interfere with these signals the selection of CO2 over humidity changes is another topic addressed in this paper.
Ulrike Schmidt, Carola Jorsch, Margarita Guenther, and Gerald Gerlach
J. Sens. Sens. Syst., 5, 409–417, https://doi.org/10.5194/jsss-5-409-2016, https://doi.org/10.5194/jsss-5-409-2016, 2016
Matthias Schelter, Jens Zosel, Wolfram Oelßner, Ulrich Guth, and Michael Mertig
J. Sens. Sens. Syst., 5, 319–324, https://doi.org/10.5194/jsss-5-319-2016, https://doi.org/10.5194/jsss-5-319-2016, 2016
Mhamed El Achhab and Klaus Schierbaum
J. Sens. Sens. Syst., 5, 273–281, https://doi.org/10.5194/jsss-5-273-2016, https://doi.org/10.5194/jsss-5-273-2016, 2016
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We have developed a preparation technique to form graphite/TiO2/Ti and platinum-graphite/TiO2/Ti solid-state sensors based on plasma electrolytic oxidation (PEO) of titanium foils, whereby a porous titanium oxide layer is formed with well-defined phase composition and a reproducible microstructure. A printing method is used to deposit graphite or catalytically active graphite-platinum electrodes. Our design enables the application of many different detection principles such as calorimetry.
Franz Schubert, Michael Gollner, Jaroslaw Kita, Florian Linseis, and Ralf Moos
J. Sens. Sens. Syst., 5, 205–212, https://doi.org/10.5194/jsss-5-205-2016, https://doi.org/10.5194/jsss-5-205-2016, 2016
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Initial steps to apply a new ceramic multi-layer sensor for a Tian–Calvet calorimeter are shown. The FEM-developed sensor consists of stacked ceramic discs and insulation rings. The functionality of the sensor disc was proven up to 600 °C and the entire stack was tested at room temperature. The resolution was 5 µW and the sensitivity was 8.5 µV mW−1. The new sensor shows similar specifications as commercial devices and presents a good starting point for future high temperature applications.
Martin Leidinger, Joni Huotari, Tilman Sauerwald, Jyrki Lappalainen, and Andreas Schütze
J. Sens. Sens. Syst., 5, 147–156, https://doi.org/10.5194/jsss-5-147-2016, https://doi.org/10.5194/jsss-5-147-2016, 2016
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For the application of indoor air quality monitoring, two types of tungsten oxide gas sensor layers were prepared via pulsed laser deposition. Analysis of the structure of the produced layers showed that they consist of nanoparticles and agglomerates of nanoparticles. The sensors showed significant sensitivity and selectivity towards naphthalene in the ppb concentration range. The results were achieved using temperature cycled operation of the sensors and pattern recognition signal treatment.
Marc-Peter Schmidt, Aleksandr Oseev, Christian Engel, Andreas Brose, Bertram Schmidt, and Sören Hirsch
J. Sens. Sens. Syst., 5, 55–61, https://doi.org/10.5194/jsss-5-55-2016, https://doi.org/10.5194/jsss-5-55-2016, 2016
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The article reports about the development of novel microfluidic sensors that are directly attachable on 3-D polymers. An ability to integrate electrical and fluidic parts into the 3-D platform brings the sensors to a new level of miniaturization. The sensor system is made of a flexible polymer featuring a system of metal electrodes and a rigid polymer carrier with all external macroconnections. To the concentration of ethanol in DI water the sensor system showed the desired sensitivity.
M. Windisch, K.-J. Eichhorn, J. Lienig, G. Gerlach, and L. Schulze
J. Sens. Sens. Syst., 5, 39–53, https://doi.org/10.5194/jsss-5-39-2016, https://doi.org/10.5194/jsss-5-39-2016, 2016
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Hydrogels are swellable polymers, which exhibit superior sensor properties. However, the exploitation of these properties for innovative measurement technology has been prevented by the lack of a manufacturing technique for thin hydogel films that suits industrial needs. We suggest a paradigm change from the current recipe-driven sensor manufacturing to a specification-driven one. Our contributions are optimized processes for a controllable film formation and thermal curing of the hydrogels.
F. Schubert, S. Wollenhaupt, J. Kita, G. Hagen, and R. Moos
J. Sens. Sens. Syst., 5, 25–32, https://doi.org/10.5194/jsss-5-25-2016, https://doi.org/10.5194/jsss-5-25-2016, 2016
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A manufacturing process for a planar binary lambda sensor is shown. By joining the heating and the sensing components via glass soldering with a joining temperature of 850 °C, a laboratory platform has been established that allows the manufacturing of two independent parts in HTCC technology with electrodes that are post-processed at lower temperatures, as is required for mixed-potential sensors. The concept has been proved by comparing the device with a commercial sensor.
S. Fischer, D. Schönauer-Kamin, R. Pohle, M. Fleischer, and R. Moos
J. Sens. Sens. Syst., 4, 321–329, https://doi.org/10.5194/jsss-4-321-2015, https://doi.org/10.5194/jsss-4-321-2015, 2015
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Thimble-type lambda probes that are known for their robustness in harsh exhausts can also be used as an NOx sensor by applying the pulsed polarization technique. This study evaluates in detail the influence of temperature on the NO sensitivity, so that an optimum operating point can be derived. Stepwise NO concentration changes between 0 and 12.5 ppm in synthetic exhausts demonstrate the high potential of this concept.
C. Weigel, M. Schneider, J. Schmitt, M. Hoffmann, S. Kahl, and R. Jurisch
J. Sens. Sens. Syst., 4, 179–186, https://doi.org/10.5194/jsss-4-179-2015, https://doi.org/10.5194/jsss-4-179-2015, 2015
L. Ebersberger and G. Fischerauer
J. Sens. Sens. Syst., 4, 85–90, https://doi.org/10.5194/jsss-4-85-2015, https://doi.org/10.5194/jsss-4-85-2015, 2015
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The current contribution reports on the substrate influence in multilayer metal-oxide chemical sensors. Measurements of the impedance are used to discuss the sensor performance with quartz substrates, (laboratory) glass substrates and substrates covered by silicon-dioxide insulating layers. Numerical experiments based on previous measurement results show that inexpensive glass substrates contribute up to 97% to the overall sensor responses.
S. Baldo, V. Scuderi, L. Tripodi, A. La Magna, S.G. Leonardi, N. Donato, G. Neri, S. Filice, and S. Scalese
J. Sens. Sens. Syst., 4, 25–30, https://doi.org/10.5194/jsss-4-25-2015, https://doi.org/10.5194/jsss-4-25-2015, 2015
M. Braik, C. Dridi, M. Ben Ali, M. Ali, M. Abbas, M. Zabala, J. Bausells, N. Zine, N. Jaffrezic-Renault, and A. Errachid
J. Sens. Sens. Syst., 4, 17–23, https://doi.org/10.5194/jsss-4-17-2015, https://doi.org/10.5194/jsss-4-17-2015, 2015
A. Hannon, Y. Lu, J. Li, and M. Meyyappan
J. Sens. Sens. Syst., 3, 349–354, https://doi.org/10.5194/jsss-3-349-2014, https://doi.org/10.5194/jsss-3-349-2014, 2014
P. Marek, J. J. Velasco-Veléz, T. Doll, and G. Sadowski
J. Sens. Sens. Syst., 3, 291–303, https://doi.org/10.5194/jsss-3-291-2014, https://doi.org/10.5194/jsss-3-291-2014, 2014
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A time-monitoring oxygen sensor based on a diffusion-controlled oxygen reaction of the indicator system methylene blue (MB)/leuco methylene blue (LMB) and riboflavin was embedded in a water-loaded poly(vinyl alcohol) (PVA) matrix. It can be used in packaging, sensors, and biotechnology applications. Since the oxygen diffusion coefficient in the PVA matrix strongly depends on temperature and humidity, two different approaches were developed within this work to compensate for these two effects.
S. Nakagomi, K. Yokoyama, and Y. Kokubun
J. Sens. Sens. Syst., 3, 231–239, https://doi.org/10.5194/jsss-3-231-2014, https://doi.org/10.5194/jsss-3-231-2014, 2014
F. Fedi, F. Ricciardella, M. L. Miglietta, T. Polichetti, E. Massera, and G. Di Francia
J. Sens. Sens. Syst., 3, 241–244, https://doi.org/10.5194/jsss-3-241-2014, https://doi.org/10.5194/jsss-3-241-2014, 2014
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We present the development of a simple and fast method for restoring exhaust graphene-based chemi-resistors used for NO2 detection. Exposing the devices repeatedly to gases or to air for more than two days, an overall worsening of the sensing signal is observed. Starting from this hypothesis and from the observation that nitrogen dioxide is soluble in water, we performed a recovery method consisting in the dipping of exhaust devices into ultrapure water at 100°C for 60 sec.
R. Gruden, A. Buchholz, and O. Kanoun
J. Sens. Sens. Syst., 3, 133–140, https://doi.org/10.5194/jsss-3-133-2014, https://doi.org/10.5194/jsss-3-133-2014, 2014
I. Marr, A. Groß, and R. Moos
J. Sens. Sens. Syst., 3, 29–46, https://doi.org/10.5194/jsss-3-29-2014, https://doi.org/10.5194/jsss-3-29-2014, 2014
M. Bastuck, C. Bur, A. Lloyd Spetz, M. Andersson, and A. Schütze
J. Sens. Sens. Syst., 3, 9–19, https://doi.org/10.5194/jsss-3-9-2014, https://doi.org/10.5194/jsss-3-9-2014, 2014
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Short summary
In this paper, we have investigated ruthenated MWCNTs/SnO2 thick-film nanocomposite sensors in the presence of propylene glycol (PG), dimethylformamide (DMF) and formaldehyde (FA) vapors in the air. The minimal PG, DMF and FA gas concentrations at which the perceptible signal is registered are 13, 5 and 115 ppm, respectively. The optimal results are shown at 200 °C operating temperature. Dependence of the response on gas concentration is linear in all cases.
In this paper, we have investigated ruthenated MWCNTs/SnO2 thick-film nanocomposite sensors in...
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