A miniaturized 2.4 GHz re-entrant cavity has been designed, manufactured and tested as a sensor for microfluidic compositional analysis. It has been fully evaluated experimentally with water and common solvents, namely methanol, ethanol, and chloroform, with excellent agreement with the expected behaviour predicted by the Debye model. The sensor's performance has also been assessed for analysis...

We report on a quartz-enhanced photoacoustic (QEPAS) sensor for methanol (CH₃OH) detection employing a novel quartz tuning fork (QTF), specifically designed to enhance the QEPAS sensing performance in the terahertz (THz) spectral range. A discussion of the QTF properties in terms of resonance frequency, quality factor and acousto-electric transduction efficiency as a function of prong sizes and...

Chemical sensing properties of phthalocyanine thin-film transistors have been investigated using nearly identical n- and p-channel devices. P-type copper phthalocyanine (CuPc) has been modified with fluorine groups to convert the charge carriers from holes to electrons. The sensor responses to the tight binding analyte dimethyl methylphosphonate (DMMP) and weak binding analyte methanol (MeOH) w...

This paper reports on work done towards the development of an odour sensing system that has the capability to distinguish between two different odours, namely ethanol and methanol. A recognition strategy has been developed that is capable of performing the aforementioned task. The odour sensor used is the commercially available gas sensor TGS2600 by Figaro. The computational requirements are pr...

Summary The coronavirus disease 2019 (COVID-19) pandemic has increased dramatically the demand for hand sanitizers. A major concern is methanol adulteration that caused more than 700 fatalities in Iran and U.S.A. (since February 2020). In response, U.S. Food Drug Administration restricted content sanitizers to 0.063 vol% blacklisted 212 products (as of November 20, Here, we present a l...

The present study correlates two simultaneous as well significant observations coming out from a single sensing prototype concerning the detection of volatile organic compounds (VOCs) by carbonaceous material based sensor. We have developed composite chemiresistive sensor utilizing different components (carbon nanotube (CNT) and zinc oxide (ZnO)). This is reflected in unique adsorption switchin...

We describe a unique UV-visible absorption spectral property of 5,10,15,20-tetrakis(4-hydroxyphenyl)porphyrin (THPP) in the presence of organophosphorus (OP) pesticides. Upon titrating each 16 among total 40 different OP pesticides, the Soret band was significantly red-shifted, and a very intense Q band appeared. They were attributed to the diprotonation of THPP. A suitable solvent for this rea...

A new method, called Shadow Clustering (SC), to build an e-nose net is proposed. The method, which is very appropriate to monitoring applications due its cheapness and low consumption, is applied to an array of sensors composed by a TiO2 thin film. A model describing the e-nose behavior is built and it is used to simulate the detection process of a mixture of Ethanol, Methanol and Propanol. The...