The Experts below are selected from a list of 180 Experts worldwide ranked by ideXlab platform
Wojciech Wroblewski - One of the best experts on this subject based on the ideXlab platform.
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miniaturized back side Contact Transducer for potentiometric sensors
Analytica Chimica Acta, 2003Co-Authors: Artur Dybko, Joanna Zachara, Jerzy Golimowski, Wojciech WroblewskiAbstract:A novel type of a miniature Transducer for potentiometric sensors was designed and tested. The Transducer is made from an ordinary printed circuit board using a typical technology. As a result, a back-side Contact structure was obtained, which can be mounted in flow systems. The advantage of the fabrication process is its cheapness and flexibility in designing modified structures. The measurement properties of the Transducer were tested as a chloride sensor. Then the structure was covered with polyHEMA and a potassium-selective membrane and tested as a potassium sensor. The performance and the long-term stability of the sensors with plasticized PVC and Siloprene based potassium-selective membranes were compared.
Ahmed Y A Sayed - One of the best experts on this subject based on the ideXlab platform.
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novel solid state potentiometric sensors using polyaniline pani as a solid Contact Transducer for flucarbazone herbicide assessment
Polymers, 2019Co-Authors: Ayman H Kamel, Nashwa S Abdalla, Mohamed Elnaggar, Mohamed A Alomar, Hamad M Alkahtani, Ahmed Y A SayedAbstract:Novel potentiometric solid-Contact ion-selective electrodes (SC/ISEs) based on molecularly imprinted polymers (MIPs) as sensory carriers (MIP/PANI/ISE) were prepared and characterized as potentiometric sensors for flucarbazone herbicide anion. However, aliquat S 336 was also studied as a charged carrier in the fabrication of Aliquat/PANI/ISEs for flucarbazone monitoring. The polyaniline (PANI) film was inserted between the ion-sensing membrane (ISM) and the electronic conductor glassy carbon substrate (GC). The sensors showed a noticeable response towards flucarbazone anions with slopes of −45.5 ± 1.3 (r2 = 0.9998) and −56.3 ± 1.5 (r2 = 0.9977) mV/decade over the range of 10−2–10−5, 10−2–10−4 M and detection limits of 5.8 × 10−6 and 8.5 × 10−6 M for MIP/PANI/ISE and Aliguat/PANI/ISE, respectively. The selectivity and long-term potential stability of all presented ISEs were investigated. The short-term potential and electrode capacitances were studied and evaluated using chronopotentiometry and electrochemical impedance spectrometry (EIS). The proposed ISEs were introduced for the direct measurement of flucarbazone herbicide in different soil samples sprayed with flucarbazone herbicide. The results agree well with the results obtained using the standard liquid chromatographic method (HPLC).
Ying Ye - One of the best experts on this subject based on the ideXlab platform.
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an all solid state screen printed carbon paste reference electrode based on poly 3 4 ethylenedioxythiophene as solid Contact Transducer
Measurement Science and Technology, 2012Co-Authors: Hui Xu, You Wang, Guang Li, Ying Chen, Ying YeAbstract:The paper presents the design of an all-solid-state portable reference electrode based on a screen-printed carbon paste electrode suitable for rapid human serum testing. The electrode was covered by electropolymerized poly(3,4-ethylenedioxythiophene) (PEDOT) doped with poly(styrenesulfonate) (PSS) as an internal solid Contact layer and polyvinyl chloride (PVC) membrane containing lipophilic anion and cation additives. The electrochemical properties of PEDOT(PSS) and PEDOT(PSS)/PVC film on a carbon paste electrode were studied by electrochemical impedance spectroscopy and cyclic voltammetry methods. The reference electrode exhibited good potential stability (for H+, Na+, K+, Ca2+, Cl− and CO2 −3/HCO−3), good reproducibility and long-term stability. The structure is applied as reference electrodes in human serum pH analysis with pH ion selective planar electrodes, forming a serum pH sensor. The response time of such a pH sensor was 15 s and the sensitivity was −52.2 ± 1.0 mV per decade. Other properties, such as repeatability, reproducibility and stability, were also evaluated. Clinical trials were carried out and compared with the results obtained from the routine hospital electrolyte analyzer, which demonstrated that their analytical performance was closely matched.
Artur Dybko - One of the best experts on this subject based on the ideXlab platform.
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miniaturized back side Contact Transducer for potentiometric sensors
Analytica Chimica Acta, 2003Co-Authors: Artur Dybko, Joanna Zachara, Jerzy Golimowski, Wojciech WroblewskiAbstract:A novel type of a miniature Transducer for potentiometric sensors was designed and tested. The Transducer is made from an ordinary printed circuit board using a typical technology. As a result, a back-side Contact structure was obtained, which can be mounted in flow systems. The advantage of the fabrication process is its cheapness and flexibility in designing modified structures. The measurement properties of the Transducer were tested as a chloride sensor. Then the structure was covered with polyHEMA and a potassium-selective membrane and tested as a potassium sensor. The performance and the long-term stability of the sensors with plasticized PVC and Siloprene based potassium-selective membranes were compared.
Rob Dwyer-joyce - One of the best experts on this subject based on the ideXlab platform.
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An Ultrasonic Sensor for Monitoring Wheel Flange/Rail Gauge Corner Contact
Proceedings of the Institution of Mechanical Engineers, Part F: Journal of Rail and Rapid Transit, 2012Co-Authors: Rob Dwyer-joyce, C. Yao, Roger Lewis, Henry BrunskillAbstract:Wheel/rail Contact is critical to the successful operation of a railway network. Contact occurs at the wheel tread/rail head and wheel flange/rail gauge corner. Contact conditions are more severe in the latter, which occurs mainly at curves. The Contact is small and supports large loads; therefore, high Contact stresses are generated. These, combined with the slip in the Contact, are primarily responsible for driving the processes that lead to wheel and rail damage, whether by deformation, wear or a fatigue process. Multi-body dynamics software is useful for predicting the wheel/rail Contact characteristics; however, there is a shortage of experimental tools available. In this study, the feasibility of an approach based on an ultrasonic sensor mounted on the wheel is investigated. The sensor emits an ultrasonic pulse which is designed to impinge on the wheel flange. If there is no Contact the pulse is fully reflected back at the flange and picked up by the same sensor. If flange Contact takes place, a proportion of the pulse amplitude will be transmitted into the rail. The signal reflected back to the sensor is therefore reduced. The amount by which this signal reduces indicates how much flange Contact has occurred. This work had two aspects. First, a standard ultrasonic ray-tracing software package was used to establish what it is possible to measure with sensors mounted in the wheel and to determine the best location and orientation. The second aspect was an experimental study to determine whether such measurements are feasible. Test specimens were cut from sections of wheel and rail, and a 2 MHz ultrasonic Contact Transducer was bonded onto the wheel in a position best suited to detect the flange Contact. The specimens were pressed together in a bi-axial loading frame to generate differing degrees of rail head and flange Contact. The reflected signal was monitored as the normal and lateral loads were varied. It proved possible not only to detect the onset of flanging, but also to record a signal that varied monotonically with both normal and lateral applied load. A map of reflected ultrasound against the applied loading is presented. The technology, while not currently suitable for full field implementation could be very useful in laboratory studies on, for example, a full-scale wheel/rail rig.
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Feasability study for an ultrasonic sensor for monitoring wheel flange Contact
Jrc2008: Proceedings of the Asme/Ieee/Asce Joint Rail Conference, 2008Co-Authors: Rob Dwyer-joyce, Roger Lewis, C. Yao, AsmeAbstract:If the Contact between the wheel and rail occurs at the flange, a high degree of slip is inherent. This can result in excessive wear and the potential for rolling Contact fatigue cracking. Multi-body dynamics software is useful for predicting the bogie and track characteristics that may lead to flange Contact occuring. However, there is a shortage of experimental tools available to validate such models or to assist in vehicle and track condition monitoring. In this study, the feasibility of a new approach is investigated. The method is based on an ultrasonic sensor mounted on the wheel. The concept is that the sensor emits an ultrasonic pulse which is designed to impinge on the wheel flange. If there is no Contact the pulse is fully reflected back at the flange and picked up by the same sensor. If flange Contact takes place, a proportion of the pulse amplitude will be transmitted into the rail. The signal reflected back to the sensor is therefore reduced. The amount by which this signal reduces indicates how much flange Contact occurs. Test specimens were cut from sections of wheel and rail, and a 2MHz ultrasonic Contact Transducer was bonded onto the wheel in a position best suited to detect the flange Contact. The specimens were pressed to together in a bi-axial loading frame to generate differing degrees of head and flange Contact. The reflected signal was monitored as the normal and lateral loads were varied. It proved possible not only to detect the onset of flanging, but also to record a signal that varied monotonically with both normal and lateral applied load. A map of reflected ultrasound against the applied loading is presented.