China
Africa
Explore chapters and articles related to this topic
Macrocyclic Receptors for Sensing the Environmentally Important Gaseous Molecules
Published in Satish Kumar, Priya Ranjan Sahoo, Violet Rajeshwari Macwan, Jaspreet Kaur, Mukesh, Rachana Sahney, Macrocyclic Receptors for Environmental and Biosensing Applications, 2022
Satish Kumar, Priya Ranjan Sahoo, Violet Rajeshwari Macwan, Jaspreet Kaur, Mukesh, Rachana Sahney
A gas sensor is a device that detects the presence of a gaseous analyte simultaneously quantifying its concentration, in a given space and real-time condition, by converting it into a detectable/measurable response. It is usually a solid-state device that is exploited in sensing different gases or analytes in the vapor phase operating at the gas-solid or gas-liquid interfaces. However, a gaseous molecular probe is different from a gas sensor since it is not a solid-state device and it usually represents a group of atoms or molecules utilized in biology or chemistry. It’s interaction with the gaseous analyte to detect them, quantifying their amount and also for the study of their properties including their structure, is by virtue of the alteration of the observable properties such as electrochemical, spectroscopic behavior (fluorescence, chemoluminescence) of the probe (Pinalli et al. 2018a). A gas sensors may involve molecular receptors in the monitoring process in the form of a thin film, a mono layer embedded in a polymer matrix or grafted on different surfaces, to improve the selectivity and sensitivity towards the gaseous analytes.
IoT Reference Architectures
Published in Stavros Shiaeles, Nicholas Kolokotronis, Internet of Things, Threats, Landscape, and Countermeasures, 2021
V. Kelli, E. G. Sfakianakis, B. Ghita, P. Sarigiannidis
Gas sensors are used in order to sense various qualities in the air, or detect the concentration of different gases, such as carbon monoxide, carbon dioxide, oxygen, etc. Their integration in IoT can be observed in many application areas. For instance, such sensors are be applied in smart cities and smart homes for carbon monoxide and other toxic gasses detection. Additionally, such technology can benefit the environment, by constantly monitoring air pollution levels and therefore aid in preventative measures to be rendered. Oxygen level recordings can be proven to be beneficial for patients in the healthcare and assisted living application areas. Additionally, in the Public Safety application area, oxygen monitoring sensors can be employed for vital checks in rescue crew.
Microheaters for Gas Sensor
Published in Sunipa Roy, Chandan Kumar Sarkar, MEMS and Nanotechnology for Gas Sensors, 2017
Sunipa Roy, Chandan Kumar Sarkar
A gas sensor can be defined as a device that identifies and confers the information about the surrounding gas atmosphere, which comprises many types of hazardous and toxic gases. The device mainly consists of a sensing layer on top of the substrate and a signal-conditioning unit. There has been extensive research on gas sensors during the last few years, particularly based on either the surface characteristics or the bulk electrolytic properties of ceramics [1–3]. Nanocrystalline metal oxide–based solid-state sensors [4–7] were found to be promising among the sensor family, as they detect a wide variety of gases like O2, H2, CO and NO2 and different volatile organic compounds [8–11] like propane, methane, ethanol, methanol and acetone with a low operating temperature, small size, low cost, high sensitivity and relatively simple associated circuitry particularly in domestic and industrial environments.
Enhanced ethanol gas sensing properties of hierarchical porous SnO2-ZnO microspheres at low working temperature
Published in Journal of Dispersion Science and Technology, 2023
Liming Song, Jiarui Zhang, Haiying Li, Xiaonian Tang
The working principle of gas sensor is based on the change of the conductivity of sensitive materials. Some detected gases make a reaction with oxygen ions that are adsorbed on the surface of sensing materials with many surface active sites, which can effectively adjust the concentration of charge the concentration of charge carrier and change the conductivity of materials.[55] Generally, the physisorbed transformed into the chemisorbed and subsequently changed into at low working temperature (< 100 °C). And the physisorbed transformed into the chemisorbed at a relative higher temperature (100 °C-300 °C).[56,57] Therefore, physisorption and chemisorption have a significant role in adjusting the gas sensing performance of the sensor based on hierarchical porous SnO2-ZnO microspheres.
Microdevices for Low-Level Acetone Gas Sensing Using Tungsten Trioxides
Published in IETE Journal of Research, 2022
Gas sensors are also used for the detection of various explosives, toxic, and flammable gases, such type of gas sensors are mostly used in the industrial and commercial purposes for pollution control and safety purposes. There are several materials and methods used for the gas detection as per the requirements. Acoustic method has long lifetime but its sensitivity is comparatively low. Gas chromatography method has high sensitivity and selectivity but it is difficult to miniaturize, also it is an expensive method for gas detection. Calorimetric method has a risk of catalyst poisoning and explosion. Optical method is costly and it is difficult to miniaturize. Carbon nanotube sensing methods use complicated and expensive fabrication techniques. Polymer materials are inexpensive but they have poor selectivity and stability for gas sensing applications, also they swell at high temperature [3–4].
Determination of chemical warfare agents by low cost differential mobility spectrometry
Published in Instrumentation Science & Technology, 2021
Dongjie Zhao, Xianqiang Li, Siqing You, Xi Yang, Jun Liu
Various sensors are required, including those for gases.[1] Gas sensors are critical components of intelligent detection systems, gaining attention due to their broad range of applications in the medical field, indoor and outdoor air quality monitoring systems, environmental science, the automotive industry, and the military.[2] Various types have been constructed, including acoustic gas sensors, carbon nanotube sensors, electrochemical gas sensors, fiber-optic gas sensors, metal oxide semiconductor sensors, organic-based gas sensors, piezoelectric gas sensors, and photonic crystal gas sensors.[3] Gas sensors should have high sensitivity to ensure the detection capability, high selectivity to prevent the interference of the irrelevant species, and fast response and recovery to guarantee efficient measurements.[4]