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1 – 10 of 243
Article
Publication date: 4 May 2020

Jayaraman Kathirvelan and Rajagopalan Vijayaraghavan

This work encompasses the various laboratory-based and portable methods evolved in recent times for sensitive and selective detection of ethylene for fruit-ripening application…

Abstract

Purpose

This work encompasses the various laboratory-based and portable methods evolved in recent times for sensitive and selective detection of ethylene for fruit-ripening application. The role of ethylene in natural and artificial fruit ripening and the associated health hazards are well known. So there is a growing need for ethylene detection. This paper aims to highlight potential methods developed for ethylene detection by various researchers, including ours. Intense efforts by various researchers have been on since 2014 for societal benefits.

Design/methodology/approach

The paper focuses on types of sensors, fabrication methods and signal conditioning circuits for ethylene detection in ppm levels for various applications. The authors have already designed, developed a laboratory-based set-up belonging to the electrochemical and optical methods for detection of ethylene.

Findings

The authors have developed a carbon nanotube (CNT)-based chemical sensor whose performance is higher than the reported sensor in terms of material, sensitivity and response, the sensor element being multi-walled carbon nanotube (MWCNT) in comparison to single-walled carbon nanotube (SWCNT). Also the authors have developed infrared (IR)-based physical sensor for the first time based on the strong IR absorption of ethylene at 10.6 µm. These methods have been compared with literature based on comparable parameters. The review highlights the potential possibilities for development of portable device for field applications.

Originality/value

The authors have reported new chemical and physical sensors for ethylene detection and quantification. It is demonstrated that it could be used for fruit-ripening applications A comparison of reported methods and potential opportunities is discussed.

Details

Sensor Review, vol. 40 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 20 March 2017

Jayaraman Kathirvelan, Rajagopalan Vijayaraghavan and Anna Thomas

The purpose of this paper was to develop a chemo-resistive sensor based on TiO2–WO3 composite material to detect and estimate ethylene released from the fruit ripening process to…

Abstract

Purpose

The purpose of this paper was to develop a chemo-resistive sensor based on TiO2–WO3 composite material to detect and estimate ethylene released from the fruit ripening process to ensure food safety.

Design/methodology/approach

The ethylene sensor has been fabricated using TiO2–WO3 composite material through the sol-gel method.

Findings

The sensitivity of the sensor obtained using the pre-calibrated ethylene is found to be 46.2 per cent at 200 ppm ethylene concentration, and the proposed sensor could measure 8 ppm as the lowest concentration.

Originality/value

The sensor was tested for continuous ethylene detection during natural ripening of fruits and hence is useful for ensuring food safety through discrimination of the type of fruit ripening. A TiO2–WO3 composite ethylene sensor is developed for the first time.

Details

Sensor Review, vol. 37 no. 2
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 16 January 2017

Jinyi Li, Zhenhui Du, Zheyuan Zhang, Limei Song and Qinghua Guo

This paper aims to provide a sensor for fast, sensitive and selective ethylene (C2H4) concentration measurements.

Abstract

Purpose

This paper aims to provide a sensor for fast, sensitive and selective ethylene (C2H4) concentration measurements.

Design/methodology/approach

The paper developed a sensor platform based on tunable laser absorption spectroscopy with a 3,266-nm interband cascade laser (ICL) as an optical source and a hollow waveguide (HWG) as a gas cell. The ICL wavelength was scanned across a C2H4 strong fundamental absorption band, and an interference-free C2H4 absorption line located at 3,060.76 cm−1 was selected. Wavelength modulation spectroscopy with the second harmonic detection (WMS-2f) technique was used to improve the sensitivity. Furthermore, the HWG gas cell can achieve a long optical path in a very small volume to improve the time response.

Findings

The results show excellent linearity of the measured 2f signal and the C2H4 concentration with a correlation coefficient of 0.9997. Also, the response time is as short as about 10 s. The Allan variance analysis indicates that the detection limit can achieve 53 ppb with an integration time of 24 s.

Practical implications

The ethylene sensor has many meaningful applications in environmental monitoring, industrial production, national security and the biomedicine field.

Originality/value

The paper provides a novel sensor architecture which can be a versatile sensor platform for fast and sensitive trace-gas detection in the mid-infrared region.

Details

Sensor Review, vol. 37 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 12 August 2022

Jayaraman Kathirvelan

The purpose of this paper is to deal with an identification of a novel ink-jet printing sensor fabrication technology for fabricating flexible carbon heaters of macro and micro…

Abstract

Purpose

The purpose of this paper is to deal with an identification of a novel ink-jet printing sensor fabrication technology for fabricating flexible carbon heaters of macro and micro sizes, carbon interdigitated (IDT) electrodes and silver IDT electrodes. The technology involved in the proposed ink-jet printing method and materials used for the formulation of homemade nano-conductive inks (digital inks) are discussed in detail. The ink-jet printed flexible carbon heaters of different sizes (macro and micro) and carbon IDT electrodes and flexible silver IDT electrodes can be used as the flexible sensing layers in electrochemical gas sensors for sensitive and selective gas sensing applications. The characterization of ink-jet printed carbon heaters on Kapton substrate and its results are discussed. Similarly, the results of formulation of silver nano-conductive ink and printing of silver IDT electrodes on Kapton and its characterization are reported here for the first time.

Design/methodology/approach

Flexible carbon heaters of different sizes (macro and micro), carbon micro-IDT electrodes and silver IDT electrodes patterns were developed using AutoCAD 2D and printed on the Kapton (polyimide sheet) flexible substrate using the home-made nano-conductive inks with the help of EpsonT60 commercial piezo-head-based drop-on demand technology printer with standard printing options.

Findings

The proposed novel method is able to print heater patterns and IDT electrode patterns of approximately 12 µm and approximately 1 µm thickness, respectively, on flexible substrate using the home-made nano-conductive inks of carbon and silver by using a commercial low-cost printer. The home-made nano-conductive inks can be re-used for multiple prints up to six months shelf life. The resistance of the carbon heater was measured as 88 O under normal atmospheric condition. The novel flexible carbon heater was tested for its functionality and found to be satisfactory. The resistance of the silver IDT flexible electrodes was measured as 9.5 O which is better than the earlier works carried out in this paper.

Research limitations/implications

The main challenge is associated with cleaning of printing ink ejection system in the existing commercial printers. The customization of the existing printer in the near future can minimize the printing challenges.

Practical implications

The novel ink-jet printing technology proposed in this work is cost-effective, capable of achieving bulk production of flexible sensor elements, and consumes the least device fabrication time and high material yielding. The printing can be done with commercial piezo-head-based ink-jet printers with custom-prepared nano-conductive inks. There is a huge market potential for this paper.

Originality/value

Both the carbon heaters and silver IDT electrodes were printed on Kapton flexible substrate by using the commercial printer for the first time. The paper is promising the revolution in flexible low-cost sensor fabrication for mass production, and it is an alternate for thin film and thick sensor fabrication methods. The future of sensor fabrication technology will be the ink-jet printing method. In this paper, the research developments of flexible carbon heaters and flexible silver IDT electrodes for the time are reported. The characterization of carbon heaters and silver IDT electrodes were carried out and confirmed that the results are favourable for gas sensor applications.

Article
Publication date: 8 August 2023

M. Yuvaraj, R. Jothi Basu, Muhammad Dan-Asabe Abdulrahman and C. Ganesh Kumar

Information and communication technology (ICT) implementation has demonstrated usefulness in supply chain coordination and efficiency optimization in various industries and…

Abstract

Purpose

Information and communication technology (ICT) implementation has demonstrated usefulness in supply chain coordination and efficiency optimization in various industries and sectors. This study investigates the extent of ICT deployment in fruits and vegetable supply chains (FVSC) from “farm-to-fork” to ensure food security.

Design/methodology/approach

This paper employs a systematic literature review (SLR) methodology and identified a total of 99 journal articles ranging from 2001 to April 2023 for analysis. The reviewed articles have been classified based on the framework proposed from the perspective of food security. Bibliometric and content analysis is carried out with the final list of articles to extract useful insights.

Findings

The findings reveal that ICT implementation in FVSC is a relatively new research area; researchers have started investigating several aspects of ICT in FVSC through varied research methodologies. Experimental research aimed at addressing food safety and condition monitoring of fruits and vegetables (FV) has started to gain traction while theory building is yet to gain traction in the literature reviewed. Findings indicate further research is required on technologies like blockchain (BCT), artificial intelligence (AI) and machine learning (ML), especially on key objectives such as food security, and the triple-bottom-line approach of sustainability. It also indicates that implementing relevant ICTs in FVSC can help delay, if not avert, the food crisis predicted by Malthusian theory.

Research limitations/implications

This study used only well-established databases to ensure quality of the studies examined. There is a possibility of missing out on articles from other sources not considered. As a result, future SLR studies may employ additional databases, such as Springer Link, Taylor and Francis, Emerald Insight and Google Scholar. Other methodologies such as expert interviews and extra empirical methodologies may also be employed to give a more balanced picture and insights into ICTs implementation in FVSC.

Practical implications

This study offers a summative detail of the status of ICT implementation in FVSC and can serve as a reference guide for stakeholders in developing strategies for efficient FVSC management. This research work highlights the impact of ICT implementation in FVSC on the four pillars of food security which include improved availability, accessibility, utilization and stability.

Originality/value

This study focuses on ICT implementation for food security in FVSC. The SLR highlights the gaps and proffers potential solutions that enhance global efforts on food security through ICT-enabled reduction in food waste and food loss in FVSC.

Details

Industrial Management & Data Systems, vol. 123 no. 9
Type: Research Article
ISSN: 0263-5577

Keywords

Article
Publication date: 2 November 2017

Nacira Mecheri, Messaoud Benounis and Houcine Barhoumi

This work aims to determine iron (III) in real water by using a new amperometric sensor on the basis of polyethylene glycol (PEG) to test and characterize a new modified selective…

Abstract

Purpose

This work aims to determine iron (III) in real water by using a new amperometric sensor on the basis of polyethylene glycol (PEG) to test and characterize a new modified selective platinum electrode.

Design/methodology/approach

In this review, the authors focus on testing and characterizing several polymeric membranes by using cyclic voltammetry and square-wave voltammetry (SWV) methods to differentiate the nature of plasticizers (2-Nitrophenyl octyl ether [NPOE], Di-n-octyl phthalate, Bis (2-ethylhexyl) sebacate, PEG. The authors have evaluated the possibility of using crown ether and three zeolite ionophore (faujasite [FAU], Chabazite and ZSM-5) matrixes as novel materials for the selective determination of iron (III) using SWV for the best membranes.

Findings

The results demonstrated that the modified platinum electrode presents linear dependence of amperometric signal with a wide linear range of 10−9 to 10−4 mol.L−1 for iron determination, revealing a detection limit of 10−10 mol.L−1 and amperometric sensibility of 58.58 µA/mol.L−1. The slope of the membrane plasticized with PEG calibration curve is six times higher than that of the other membranes. It was noticed that when the crown ether and the three zeolite ionophores were used, as a new detective material for iron with the membrane plasticized with PEG, the expected results were highly proven. The modified platinum electrode showed high selectivity to iron (III) when the heavy metal ions such as Ni (II), Al (III), Zn (III), Cd (II), Gd (II) and Cu (II) were present.

Originality/value

The utility of the method and the efficiency of the best membrane sensor have been accurately tested by the determination of iron in real water samples of Hassi Messaoud, south of Algeria.

Details

Sensor Review, vol. 37 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 11 September 2009

L. Li and C. Wang

The purpose of this paper is to research the durability of the adhesive‐poly(ethylene terephthalate) film joints.

Abstract

Purpose

The purpose of this paper is to research the durability of the adhesive‐poly(ethylene terephthalate) film joints.

Design/methodology/approach

The adhesive‐poly(ethylene terephthalate) joints are prepared with poly ethylene terephthalate film synthesised from thioglycolic acid, terpene hydrocarbon resin and acetone resolution at room temperature. These joints are characterised by methods of peel strength tests, energy dispersive X‐ray spectroscopy (EDX) and analysis of glass transition temperature (Tg) to examine their durability.

Findings

Peel strength tests and EDX analyses prove that water diffusion in different humidity aging conditions causes similar changes, namely having the time‐temperature equivalence at 45°C for 200, 300, 500 and 600 h, respectively, almost corresponding with those at 55°C for 100, 200, 300 and 400 h, respectively, and at 65°C for 50, 100, 150 and 200 h, respectively. The changes in EDX spectra of adhesive‐poly(ethylene terephthalate) film joints indicate that the rate of water penetration in the adhesive is faster than that in the poly(ethylene terephthalate) film. In humidity aging process, the decline ratio of peel strength of adhesive‐poly(ethylene terephthalate) film joints treated with Co60 irradiation is lower than that treated with acetone washing or chemical treatment.

Originality/value

The paper shows that using EDX for analysis of durability of adhesive film joints is of significance to industrial process.

Details

Pigment & Resin Technology, vol. 38 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 March 1965

MICHAEL BASSEY

PART V Organic chemistry textbooks. Twenty textbooks of organic chemistry are considered in this part of the review and the organic sections of the syllabuses of three GCE Boards…

Abstract

PART V Organic chemistry textbooks. Twenty textbooks of organic chemistry are considered in this part of the review and the organic sections of the syllabuses of three GCE Boards are analysed.

Details

Education + Training, vol. 7 no. 3
Type: Research Article
ISSN: 0040-0912

Article
Publication date: 1 November 1979

R.A. Ellis

(b) Linear Homopolymers Linear poly(vinyl acetate) and polybutadiene samples were studied by Park and Graessley using GPC combined with capillary viscometry which provided both…

Abstract

(b) Linear Homopolymers Linear poly(vinyl acetate) and polybutadiene samples were studied by Park and Graessley using GPC combined with capillary viscometry which provided both the distribution of hydrodynamic volumes and intrinsic viscosities of the samples. Their equipment comprised a Waters Associates Chromatograph (model 200) fitted with five Styragel columns of porosities 106, 105, 1.5 × 104, 104 and 3 and 103 mm eluted with THF at room temperature at a flow rate of 1 cm3 min−1. Samples of 2 cm3 nominal volume were injected at a concentration of 0.25 g per 100 cm3 and detection was by a differential refractometer coupled to a digital curve translator so that readings were digitised and fed to a teletype machine at one minute intervals. From the refractometer, the sample passed via a syphon device into an all glass viscometer of the Ubbelohde type and the whole of this equipment was totally immersed in a water bath whose volume was sufficient to smooth out minor temperature variations in the equipment. The viscometer discharge was detected photoelectrically and the time taken determined by an electronic timer which gave a signal that was also recorded on the teletype.

Details

Pigment & Resin Technology, vol. 8 no. 11
Type: Research Article
ISSN: 0369-9420

Article
Publication date: 4 April 2018

Bushra Rafique, Mudassir Iqbal, Tahir Mehmood and Muhammad Ashraf Shaheen

This review aims to focus on recent reported research work on the construction and function of different electrochemical DNA biosensors. It also describes different sensing…

1860

Abstract

Purpose

This review aims to focus on recent reported research work on the construction and function of different electrochemical DNA biosensors. It also describes different sensing materials, chemistries of immobilization probes, conditions of hybridization and principles of transducing and amplification strategies.

Design/methodology/approach

The human disease-related mutated genes or DNA sequence detection at low cost can be verified by the electrochemical-based biosensor. A range of different chemistries is used by the DNA-based electrochemical biosensors, out of which the interactions of nanoscale material with recognition layer and a solid electrode surface are most interesting. A diversity of advancements has been made in the field of electrochemical detection.

Findings

Some important aspects are also highlighted in this review, which can contribute in the creation of successful biosensing devices in the future.

Originality/value

This paper provides an updated review of construction and sensing technologies in the field of biosensing.

Details

Sensor Review, vol. 39 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

1 – 10 of 243