scholarly journals Low-Power Detection of Food Preservatives by a Novel Nanowire-Based Sensor Array

Foods ◽  
2019 ◽  
Vol 8 (6) ◽  
pp. 226 ◽  
Author(s):  
Dario Zappa
Keyword(s):  
Metal Oxide ◽  
Shelf Life ◽  
Sensor Array ◽  
Sensor Arrays ◽  
Principal Component ◽  
Industrial Applications ◽  
Food Preservatives ◽  
Electronic Noses ◽  
Long Time ◽  
Sensors Array

Food preservatives are compounds that are used for the treatment of food to improve the shelf life. In the food industry, it is necessary to monitor all processes for both safety and quality of the product. An electronic nose (or e-nose) is a biomimetic olfactory system that could find numerous industrial applications, including food quality control. Commercial electronic noses are based on sensor arrays composed by a combination of different sensors, which include conductometric metal oxide devices. Metal oxide nanowires are considered among the most promising materials for the fabrication of novel sensing devices, which can enhance the overall performances of e-noses in food applications. The present work reports the fabrication of a novel sensor array based on SnO2, CuO, and WO3 nanowires deposited on top of μHPs provided by ams Sensor Solutions Germany GmbH. The array was tested for the discrimination of four typical compounds added to food products or used for their treatment to increase the shelf life: ethanol, acetone, nitrogen dioxide, and ozone. Results are very promising; the sensors array was able to operate for a long time, consuming less than 50 mW for each single sensor, and principal component analysis (PCA) confirmed that the device was able to discriminate between different compounds.

scholarly journals Low-Power Detection of Food Preservatives by a Novel Nanowire-Based Sensor Array

2019 ◽  
Author(s):  
Dario Zappa
Keyword(s):  
Metal Oxide ◽  
Shelf Life ◽  
Sensor Array ◽  
Sensor Arrays ◽  
Industrial Applications ◽  
Food Preservatives ◽  
Electronic Noses ◽  
Long Time ◽  
Sensors Array ◽  
Food Applications

Food preservatives are compound that are used for the treatment of food to improve the shelf life. In the food industry, is necessary to monitor all processes, for both safety and quality of the product. An electronic nose (or e-nose) is a biomimetic olfactory system that could find numerous industrial applications, including food quality control. Commercial electronic noses are based on sensor arrays composed by a combination of different sensors, which include conductometric metal oxide devices. Metal oxide nanowires are considered among the most promising materials for the fabrication of novel sensing devices, which can enhance the overall performances of e-noses in food applications. In the present work, is reported the fabrication of a novel sensor array based on SnO2, CuO and WO3 nanowires deposited on top of commercial μHPs, provided by ams Sensor Solutions Germany GmbH. The array was tested for the discrimination of four typical compounds added to food products or used for their treatment to increase the shelf life: ethanol, acetone, nitrogen dioxide and ozone. Results are very promising: the sensors array was able to operate for long time consuming less than 50mW for each single sensor, and PCA analysis confirms that the device was able to discriminate between different compounds.

Combinatorial selectivity with an array of phthalocyanines functionalized TiO2/ZnO heterojunction thin film sensors

2021 ◽  
Author(s):  
Yuvaraj Sivalingam ◽  
Gabriele Magna ◽  
Ramji Kalidoss ◽  
Sarathbavan Murugan ◽  
David Chidambaram ◽  
...  
Keyword(s):  
Sensor Array ◽  
Principal Component ◽  
Optically Active ◽  
Inorganic Materials ◽  
Chemical Sensitivity ◽  
Electronic Noses ◽  
Thin Film Sensors ◽  
Sensor Resistance ◽  
Virtual Array ◽  
Hydrogen Bond Basicity

Abstract The development of electronic noses requires the control of the selectivity pattern of each sensor of the array. Organic chemistry offers a manifold of possibilities to this regard but in many cases the chemical sensitivity is not matched with the response of electronic sensor. The combination of organic and inorganic materials is an approach to transfer the chemical sensitivities of the sensor to the measurable electronic signals. In this paper, this approach is demonstrated with a hybrid material made of phthalocyanines and a bilayer structure of ZnO and TiO2. Results show that the whole spectrum of sensitivity of phthalocyanines results in changes of the resistance of the sensor, and even the adsorption of compounds, such as hexane, which cannot change the resistance of pure phthalocyanine layers, elicits changes of the sensor resistance. Furthermore, since phthalocyanines are optically active, the sensitivity in dark and visible light are different. Thus, operating the sensor in dark and light two different signals per sensors can be extracted. As a consequence, an array of 3 sensors made of different phthalocyanines results in a virtual array of six sensors. The sensor array shows a remarkable selectivity respect to a set of test compounds. Principal component analysis scores plot illustrates that hydrogen bond basicity and dispersion interaction are the dominant mechanisms of interaction.

scholarly journals Cocaine by-product detection with metal oxide semiconductor sensor arrays

RSC Advances ◽  
2020 ◽  
Vol 10 (47) ◽  
pp. 28464-28477
Author(s):  
Paula Tarttelin Hernández ◽  
Stephen M. V. Hailes ◽  
Ivan P. Parkin
Keyword(s):  
Metal Oxide ◽  
Gas Sensors ◽  
Sensor Array ◽  
Sensor Arrays ◽  
Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Semiconductor Sensor ◽  
Gas Sensor Array ◽  
Semiconductor Gas Sensors ◽  
Metal Oxide Semiconductor Sensor

Metal oxide semiconductor gas sensors based on SnO2 and Cr2O3 were modified with zeolites H-ZSM-5, Na-A and H–Y to create a gas sensor array to detect cocaine by-product, methyl benzoate. SVMs were later used with a 4 sensor array to classify 9 gases of interest.

scholarly journals Highly Sensitive p + n Metal Oxide Sensor Array for Low-Concentration Gas Detection

Sensors ◽  
2018 ◽  
Vol 18 (8) ◽  
pp. 2710
Author(s):  
Jianghua Luo ◽  
Yishan Jiang ◽  
Feng Xiao ◽  
Xin Zhao ◽  
Zheng Xie
Keyword(s):  
Electron Microscopy ◽  
Metal Oxide ◽  
Gas Sensors ◽  
Sensor Array ◽  
Gas Sensing ◽  
Sensor Arrays ◽  
Low Concentration ◽  
Highly Sensitive ◽  
Doped Zno ◽  
P Type

Nowadays, despite the easy fabrication and low cost of metal oxide gas sensors, it is still challenging for them to detect gases at low concentrations. In this study, resistance-matched p-type Cu2O and n-type Ga-doped ZnO, as well as p-type CdO/LaFeO3 and n-type CdO/Sn-doped ZnO sensors were prepared and integrated into p + n sensor arrays to enhance their gas-sensing performance. The materials were characterized by scanning electron microscopy, transmittance electron microscopy, and X-ray diffractometry, and gas-sensing properties were measured using ethanol and acetone as probes. The results showed that compared with individual gas sensors, the response of the sensor array was greatly enhanced and similar to the gas response product of the p- and n-type gas sensors. Specifically, the highly sensitive CdO/LaFeO3 and CdO/Sn-ZnO sensor array had a high response of 21 to 1 ppm ethanol and 14 to 1 ppm acetone, with detection limits of <0.1 ppm. The results show the effect of sensor array integration by matching the two sensor resistances, facilitating the detection of gas at a low concentration.

scholarly journals A Patent Analysis to Identify Emergent Topics and Convergence Fields: A Case Study of Chitosan

2021 ◽  
Vol 13 (16) ◽  
pp. 9077
Author(s):  
Worasak Klongthong ◽  
Veera Muangsin ◽  
Chupun Gowanit ◽  
Nongnuj Muangsin
Keyword(s):  
Shelf Life ◽  
Principal Component ◽  
Industrial Applications ◽  
Growth Patterns ◽  
Socially Responsible ◽  
Patent Classification ◽  
Medical Needs ◽  
The Status ◽  
Technology Convergence ◽  
Degree Of Convergence

Identifying emerging technology trends from patents helps to understand the status of the technology commercialization or utilization. It could provide research insights leading to advanced technological innovations that stimulate socially responsible research to address human dietary and medical needs. However, few studies have investigated emerging chitosan applications using patents. In this study, we report the application of a patent bibliometric predictive intelligence (PBPI) model to identify emergent topics and technology convergence related to chitosan applications from patents in the International Patent Classification system. Text mining was used to extract patterns from 5001 patents and each term was assigned an emergent score, following which we traced growth patterns, examined relationships between IPCs, emergent topics, and patents using correlation analysis and principal component analysis, and conducted matrix and cluster mapping analysis to understand industrial applications and explore patterns of technological convergence. Five major terms emerged in association with ascending and newly emergent topics over the last 13 years: “shelf life,” “antibacterial,” “good safety,” “absorbing water,” and “auxiliary materials.” These topics were closely linked with research in the biomedical and food production and preservation industries. A network analysis indicated that “antibacterial” terms exhibited the highest degree of convergence, followed by “shelf life.” These findings can inform strategies to determine new directions for chitosan research.

scholarly journals Discrimination Improvement of a Gas Sensors’ Array Using High-Frequency Quartz Crystal Microbalance Coated with Polymeric Films

Sensors ◽  
2020 ◽  
Vol 20 (23) ◽  
pp. 6972
Author(s):  
Marcos Rodríguez-Torres ◽  
Víctor Altuzar ◽  
Claudia Mendoza-Barrera ◽  
Georgina Beltrán-Pérez ◽  
Juan Castillo-Mixcóatl ◽  
...  
Keyword(s):  
Discriminant Analysis ◽  
Quartz Crystal Microbalance ◽  
Quartz Crystal ◽  
Sensor Arrays ◽  
Principal Component ◽  
Polymeric Films ◽  
Static System ◽  
Similar System ◽  
Casting Technique ◽  
Sensors Array

The discrimination improvement of an array of four highly sensitive 30 MHz gas quartz crystal microbalance (QCM) sensors was performed and compared to a similar system based on a 12-MHz QCM. The sensing polymeric films were ethyl cellulose (EC), poly-methyl methacrylate (PMMA), Apiezon L (ApL), and Apiezon T (ApT) and they were coated over the AT-cut QCM devices by the drop casting technique. All the sensors had almost the same film thickness (0.2 μm). The fabricated QCM sensor arrays were exposed to three different concentrations, corresponding to 5, 10, and 15 μL, of ethanol, ethyl acetate, and heptane vapors. The steady state sensor responses were measured in a static system at a temperature of 20 °C and relative humidity of 22%. Our results showed that the 30-MHz sensors have a higher sensitivity than 12-MHz ones (around 5.73 times), independently of the sensing film and measured sample. On the other hand, principal component analysis and discriminant analysis were performed using the raw data of the responses. An improvement of the classification percentage between 12 MHz and 30 MHz sensors was found. However, it was not sufficient, especially for low concentrations. Furthermore, using partition coefficient and discriminant analysis (DA), an improvement of 100% classification of the three samples was achieved for the case of the 30-MHz sensor array.

Fluorescence Quenching Sensor Arrays for the Discrimination of Nitroaromatic Vapors

2018 ◽  
pp. 58-93
Author(s):  
Nico Bolse ◽  
Anne Habermehl ◽  
Carsten Eschenbaum ◽  
Uli Lemmer
Keyword(s):  
Fluorescence Quenching ◽  
Sensor Arrays ◽  
Principal Component ◽  
Future Research ◽  
Sensor Systems ◽  
Vapor Detection ◽  
Electronic Noses ◽  
Theoretical Concepts ◽  
Linear Discriminant ◽  
Practical Applications

Fluorescence quenching is a promising technique for chemical sensing applications such as the detection of explosive trace vapors. Nitroaromatic explosives are one of the primary targets for this approach enabling ultra-low detection limits down to sub parts-per-billion in air. Many studies, however, focus on enhanced sensor sensitivity, whereas practical applications often require the identification and quantification of detected species. Electronic noses and efficient sensor systems are a promising solution to address this challenge. The authors review recent approaches and trends for explosive trace vapor detection and discuss theoretical concepts for fluorescence quenching as well as target analytes, sensor materials, and fabrication techniques. Statistical learning techniques such as principal component analysis and linear discriminant analysis, sensor systems, and camera-based read-out strategies are in the focus of the chapter. The authors conclude with recommendations and solutions for the elaborated challenges and with visions on future research directions.

PENELITIAN DAN PENGEMBANGAN SENSOR AROMATIK SEBAGAI ALAT DETEKSI ALKOHOL PADA PARFUM DAN WEWANGIAN UNTUK AUTENTIKASI PRODUK PARFUM HALAL

2017 ◽  
Vol 18 (2) ◽  
pp. 302-322
Author(s):  
Fajar Hardoyono
Keyword(s):  
Sensor Array ◽  
Principal Component ◽  
Metal Oxide Semiconductor ◽  
Oxide Semiconductor ◽  
Response Patterns ◽  
Data Recording ◽  
Analysis Method ◽  
Sample Group ◽  
Array Pattern ◽  
Group Data

Abstract: The development of aromatic sensor array instrument for the detection of alcohol in perfume. The research was conducted by developing the sensor array using 8 sensors made of metal oxide semiconductor. The sensor types used in this study consisted of TGS 813, TGS 822, TGS 2600, TGS 826, TGS 2611, TGS 2620, TGS 2612 and TGS 2602. Response patterns of 8 sensors formed a sensor array pattern used to detect the aroma of 2 groups of samples perfume made from the essential oil of ginger. The first sample group is pure ginger atsiri oil without mixed alcohol. The second sample group was made from the ginger atsiri oil mixed with alcohol with a level of 0.02 M. The results of the data recording show that the developed instrument is able to dissect the first sample group with the second sample group. Data analysis using principal component analysis method (PCA shows that the instrument is able to distinguish the contaminated alcohol perfume group 0.2 M with the alcohol-free perfume group with 100% accuracy. Keywords: Sensor Aroma, Perfume.

scholarly journals Metal Oxide-Related Dendritic Structures: Self-Assembly and Applications for Sensor, Catalysis, Energy Conversion and Beyond

Nanomaterials ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1686
Author(s):  
Ruohong Sui ◽  
Paul A. Charpentier ◽  
Robert A. Marriott
Keyword(s):  
Metal Oxide ◽  
Energy Conversion ◽  
Self Assembly ◽  
Hierarchical Structures ◽  
The Self ◽  
Assembly Process ◽  
Electronic Noses ◽  
Dendritic Nanostructures ◽  
Energy Conversion And Storage ◽  
The Aesthetic

In the past two decades, we have learned a great deal about self-assembly of dendritic metal oxide structures, partially inspired by the nanostructures mimicking the aesthetic hierarchical structures of ferns and corals. The self-assembly process involves either anisotropic polycondensation or molecular recognition mechanisms. The major driving force for research in this field is due to the wide variety of applications in addition to the unique structures and properties of these dendritic nanostructures. Our purpose of this minireview is twofold: (1) to showcase what we have learned so far about how the self-assembly process occurs; and (2) to encourage people to use this type of material for drug delivery, renewable energy conversion and storage, biomaterials, and electronic noses.

Effects of slide-to-roll ratio and varying velocity on the lubrication performance of grease at low speed

2021 ◽  
pp. 135065012199336
Author(s):  
Yiming Han ◽  
Jing Wang ◽  
Xuyang Jin ◽  
Shanshan Wang ◽  
Rui Zhang
Keyword(s):  
Steady State ◽  
Critical Speed ◽  
Industrial Applications ◽  
Transient Effects ◽  
Disintegration Time ◽  
Low Speed ◽  
Existence Time ◽  
Pure Rolling ◽  
Lubrication Performance ◽  
Long Time

Under steady-state pure rolling conditions with low speed, the thickener fiber agglomerations can be maintained for a long time, generating a beneficial thicker film thickness. However, in industrial applications, motions with sliding or transient effects are very common for gears, rolling-element bearings or even chain drives, evaluation of the grease performance under such conditions is vital for determining the lubrication mechanism and designing new greases. In this project, optical interferometry experiments were carried out on a ball-disk test rig to study the disintegration time of the grease thickener agglomerations with the increase of the slide-to-roll ratio under steady-state and reciprocation motions. Under steady-state conditions, the thickener fiber agglomeration can exist for a while and the time becomes shorter with the increase of the slide-to-roll ratio above the critical speed. Below the critical speed, the thickener fiber can exist in the contact in the form of a quite thick film for a very long time under pure rolling conditions but that time is decreased with the increase of the slide-to-roll ratio. The introduction of the transient effect can further reduce the existence time of the thickener.

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