96 research outputs found
A sensor which can be varied in humidity sensitivity: a first experience paving the way to new chemical sensors?
No full textDuring last decades, a number of different sensors have been developing for different analytics to detect. A key aspect of those sensors is that each of them results with a fixed particular sensitivity. Consequently, at occurrence, it is necessary to use a plurality of sensors to arrange measures with different levels of sensitivity. This work intends to investigate the possibility to obtain different sensitivity, in particular with respect to humidity, from one sensor only. To this aim we investigated the resistive flex sensor, which has been already used for other applications but, as far as we know, never investigated for its potential properties as a chemical sensor. Results demonstrated how the resistive flex sensor behaves with different sensitivity values and different sensitivity curves for different bend conditions. Copyright © 2018 by SCITEPRESS – Science and Technology Publications, Lda. All rights reserved
Evaluation of a multisensorial system for a rapid preliminary screening of the olive oil chemical compounds in an industrial process
No full textIn this study, a sensory system, named BIONOTE, based on gas and liquid analyses was used to analyse the headspace of olive oil samples obtained at the end of the extraction process for a preliminary screening of the volatile and phenolic compounds. Olive oil samples were obtained using different olive paste conditioning systems, including microwave and megasound machines at different processing time. The same olives batch was used for the entire test. BIONOTE showed the ability toon-commediscriminate between 64 virgin olive oils originated from different technologies or by using different process parameters, as demonstrated by the partial least square discriminant analysis (PLS-DA) models calculated. The percentage of correct classification in different conditions are in a range from 92.19% to 100%. In addition, the research shown that the multisensorial system can provide a preliminary estimation of some volatile and phenolic compounds concentrations detected by laboratory analysis. Data analysis has been performed using multivariate data analysis techniques: PLS-DA cross validation via leave one out criterion. Future perspectives are to further develop BIONOTE in order to increase the number of detected chemical compounds and finally to include the mathematical models obtained in the BIONOTE microcontroller for a rapid chemical characterization of olive oil in the mill
Investigating a single sensor ability in the characterisation of drinkable water: a pilot study
No full textTowards Smart Sensor Systems for Precision Farming: Electrode Potential Energy Harvesting from Plants' Soil
No full textThe purpose of this paper is to present a study on the characterization of living plants as an energy source for low-power devices and autonomous sensors. The proliferation of the Internet of Things (IoT) and distributed monitoring has increased the demand for autonomous, low-power, long-lasting smart devices. As a result, research on zero-cost, bio-impact-reduced alternative energy sources in the surrounding environment is expanding. This research illustrates the viability of a plant-based energy harvesting device capable of continuously extracting up to 53.5 μW. Future research on practical electronic systems can now include the energy extraction process from living plants to power embedded systems for plant monitoring and other similar applications useful for precision farming
Innovative IAQ Organic Sensor
No full textAbstractAn innovative organic sensor for the monitoring of indoor air quality is described. For office buildings and schools the main requirements are: temperature, RH %, O2 and CO2 concentrations. Moreover low O2 and high CO2 concentrations can be hazardous. There are a lot of sensors based on different principal transducers that are able to detect very low concentrations of CO2, O2, and RH%.The system is based on a resistive interdigital sensor based on an organic sensing material, anthocyanin. Anthocyanins are natural pigments widely distributed in nature: they are produced by plants as secondary metabolites responsible for the pigmentation of many flowers, fruits and vegetables. In this work authors show the possibility to use this innovative organic sensor to monitor indoor air quality by measuring O2 concentration shifts with respect to a standard of 20% (20.000ppm) and the critical CO2 concentration value of about 5% (5000ppm) which is comparable with OSHA (Occupational Safety & Health Administration) standard in an eight-hour time-weighted average (TWA)
BIONOTE as an innovative biosensor for measuring endocannabinoid levels
No full textIn this study, a novel approach was developed to quantify endocannabinoids (eCBs), and was based on the liquid biosensor BIONOTE. This device is composed of a probe that can be immersed in a solution, and an electronic interface that can record a current related to the oxy-reductive reactions occurring in the sample. The two most representative members of eCBs have been analysed in vitro by BIONOTE: anandamide (N-arachidonoylethanolamine, AEA) and 2-arachidonoylglycerol (2-AG). Bovine serum albumin was used to functionalize the probe and improve the sensibility of the whole analytical system. We show that BIONOTE is able to detect both AEA and 2-AG at concentrations in the low nanomolar range, and to discriminate between these eCBs and their moieties arachidonic acid, ethanolamine and glycerol. Notably, BIONOTE distinguished these five different molecules, and it was also able to quantify AEA in human plasma. Although this is just a proof-of-concept study, we suggest BIONOTE as a cheap and user-friendly prototype sensor for high throughput quantitation of eCB content in biological matrices, with an apparent diagnostic potential for tomorrow’s medicine
Development and test of a portable ecg device with dry capacitive electrodes and driven right leg circuit
No full textThe use of wearable sensors for health monitoring is rapidly growing. Over the past decade, wearable technology has gained much attention from the tech industry for commercial reasons and the interest of researchers and clinicians for reasons related to its potential benefit on patients’ health. Wearable devices use advanced and specialized sensors able to monitor not only activity parameters, such as heart rate or step count, but also physiological parameters, such as heart electrical activity or blood pressure. Electrocardiogram (ECG) monitoring is becoming one of the most attractive health-related features of modern smartwatches, and, because cardiovascular disease (CVD) is one of the leading causes of death globally, the use of a smartwatch to monitor patients could greatly impact the disease outcomes on health care systems. Commercial wearable devices are able to record just single-lead ECG using a couple of metallic contact dry electrodes. This kind of measurement can be used only for arrhythmia diagnosis. For the diagnosis of other cardiac disorders, additional ECG leads are required. In this study, we characterized an electronic interface to be used with multiple contactless capacitive electrodes in order to develop a wearable ECG device able to perform several lead measurements. We verified the ability of the electronic interface to amplify differential biopotentials and to reject common-mode signals produced by electromagnetic interference (EMI). We developed a portable device based on the studied electronic interface that represents a prototype system for further developments. We evaluated the performances of the developed device. The signal-to-noise ratio of the output signal is favorable, and all the features needed for a clinical evaluation (P waves, QRS complexes and T waves) are clearly readable
Design and development of an electronic interface for gas detection and exhaled breath analysis in liquids
No full textA Ladder Network Theoretical Approach for the Automatic Monitoring of Distributed Sensors
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