Chemical Detection System Research Articles

Navigating the biomechanical landscape: Enhanced methods for drug analysis

In drug analysis and detection, chemiluminescence is a standard technical method based on the idea that the concentration of observed substances in the chemical detection system and the chemical luminescence intensity establish a linear quantitative relationship under certain conditions. Bio-mechanical landscape (BML), which uses bioengineered systems to simulate essential elements of the human tumour microenvironment, is already enhancing cancer biology and aiding clinical translation. The majority of illicit substances have dangerous cardiovascular side effects that might range from an irregular heartbeat to a heart attack. Cardiovascular disease, including blocked veins and bacterial infections of the blood arteries and heart valves, may also result from injecting illicit narcotics. The challenging characteristics of such a cardiovascular disease using drug analysis are heart failure, low blood pressure and headaches. Hence, in this research, drug analysis has improved wearable body sensor network-enabled artificial neural network (WBSN-ANN) technologies for cardiovascular disease. Medicine and drug development because they provide information on patient status in the clinical context and vital information on pharmacodynamics activity, effectiveness, and safety throughout the research process. The process results in a research-intensive organization finding a novel chemical or biological compound and developing it into a medicine that patients can legally utilize for drug discovery and development.

Microcontroller Based System for Detection of Harmful Chemicals on Fruits and Vegetables

Abstract: Resources are getting limited with the increasing population. The incessant drive to meet food demands compels farmers to augment crop production using both natural and artificial means, including chemical fertilizers and pesticides. While these substances safeguard crops against pests and fungi, their excessive use compromises food quality and poses health risks due to their infiltration into the food chain. Recognizing this issue, there is a pressing need for a portable device capable of analyzing the organic composition of edibles. This study endeavors to ascertain both organic and inorganic elements present in food items, empowering consumers to make informed choices about their consumption. Central to this research is the development of an electronic device utilizing infrared technology to detect chemical residues. By displaying the ratio of organic to inorganic components, consumers can utilize this data as a guideline for selecting safe-to-consume food products,here we are proposed a portable device which makes it easy to identify whether the fruit is organic or inorganic based on this consumer can conclude what to eat and what should not eat.

Research on Dry Chemical Detection TechnologyBased on Reflectance Photometry

In response to the issues of insufficient stability and accuracy in dry chemical detection using reflectance photometry, caused by the divergence and multiple internal reflections of the reflected light signal from the sample and the multilayer dry film test strip, a dry chemical reflectance photometry detection system based on an integrating sphere is designed. Firstly, an integrating sphere device is incorporated to reduce signal divergence and loss, ensuring even detection of the sample's reflected light signal and improving detection stability. Secondly, Light Tools optical simulation analysis is performed, and an integrating sphere detection model is established. Thirdly, the Williams-Clapper equation is employed to correct the error in reflectance density caused by multiple internal reflections, enhancing detection accuracy. Experimental validation demonstrates that the developed integrating sphere-based dry chemical reflectance photometry detection system improves the stability and accuracy of the detection system.

Differential absorption lidar data acquisition and control system for remote detection of trace chemicals including methane and thiodiglycol.

We report the design and development of a data acquisition and control system for high-speed acquisition of weak, backscattered differential signals and synchronized sequential operation of all subsystems of a tunable, mid-infrared Differential Absorption Lidar (DIAL) system. The presence of a low-level concentration of chemical species results in weak differential return signals. The differential signal also varies dynamically with respect to background atmospheric conditions. The challenge is to measure this low level of differential signal with high resolution and also control the sequence of operation of subsystems such as lasers and scanners for real time testing and evaluation in open field conditions. The concentration spread of the chemical species varies rapidly with distance. In order to capture this spatial variation, the lidar signal should be sampled and digitized at a high sampling rate. A customized Peripheral Component Interconnect based data acquisition of a 12-bit resolution, 30 Mega samples per second sampling rate, and an industrial personal computer-based control system has been realized. Detection algorithms and the firing sequence of the laser have been developed indigenously and implemented in the LabVIEW platform. The developed graphical user interface has various modes of operation as per user requirement and is capable of executing automatic operations for the developed DIAL system in order to detect and identify the chemicals. The performance has been evaluated by detecting the chemical species thiodiglycol at 800m using 3190 and 3300nm (online and offline wavelengths) with a differential cross-section of 2.5 × 10-23m2. Similarly, methane has been detected and quantified with concentration of 2.2 ppm up to 300m using 3316 and 3326nm (online and offline wavelengths, respectively).

Machine Learning-Based IOT Air Quality and Pollution Detection

In India, gas leakage from the different factories harmful to human surveying in the last fifty years is very low. However, there is a lack of prior detection of the chemical gases detection system in the situation raised. So, In this regard, there is a gap identification of chemical gases intensity detection needed. In this work, the main objective is to identify chemical gases intensity and maintain the stream data in the database from different locations. To fill this gap, that is identifying the high-intensity chemical gases from the chemical gas disaster areas. The first step needs to identify the different chemical gases and natural gas compositions. In this regard in this work for design internet-based gases in the air system. So, the sensors MQ2(Ethanol i-Butane Methane Alcohol Gas Sensor Sensor), MQ3(Sensitivity Alcohol Detector), MQ4 (Methane and Natural Gas (CNG)), MQ-5 ( LPG GAS SENSOR), MQ-7 (CO Gas Sensor Module Test Carbon Monoxide Detector), MQ-8 (hydrogen Gas Sensor), MQ-9 (carbon monoxide), MQ-135 Sensor(Air Quality Sensor Hazardous Gas Detector) and DHT11 Digital Temperature Humidity Sensors. These sensors are interfacing with the micro-control STM 32 board. It is also called one Pollution identification terminal by using it to pull the sensor stream data from location to centralized data. This stream data transportation is a service to pull the data. For this Data pulling, design an algorithm store into a cloud database. In this research work, design the electronic terminal with a wifi circuit using IoT technologies.Moreover, getting these attributes as data. Data need to apply the preprocessing techniques and extracted feature techniques also. This paper discusses mainly designing the terminal for pollution attributes , cleaning the data, and applying the Machine Learning based Feature extraction techniques.

QCL Active Area Modeling with a View to Being Applied to Chemical Substance Detection Systems

Numerical research into the QCL tunability aspects in respect to being applied in chemical substance detection systems is covered in this paper. The QCL tuning opportunities by varying power supply conditions and geometric dimensions of the active area have been considered. Two models for superlattice finite (FSML) and infinite (RSM) size were assumed for simulations. The results obtained have been correlated with the absorption map for selected chemical substances in order to identify the potential detection possibilities.

Allometry and morphological integration shape the chemical detection system in Liolaemus lizards (Squamata, Iguania)

The chemosensory system in tetrapods consists of glands that emit chemical signals and specialized organs that capture these signals. Lizards mostly depend on this chemosensory modality and different relationships have been suggested among components of their chemical detection systems; the vomeronasal organ (VNO), palatal openings (PO) and tongue morphology (TM), as well as epidermal glands and their secretions. In this study, we used phylogenetic geometric morphometrics to examine shape variation in the VNO, PO and TM of 20 species of Liolaemus lizards. First, we tested whether phylogeny, allometry or diet type influenced their shape. Second, we tested an integration hypothesis between the shapes of the VNO, palatal opening and tongue, as well as, their association with the number of precloacal epidermal glands (PEG). Third, we tested the relationship between the evolutionary change rates of trait shape. Results showed a weak phylogenetic effect on shapes and an allometry effect on the shape of PO. The diet type did not affect the shape of these traits as well as, the number of precloacal epidermal glands. The tongue shape showed significant integration patterns with both the shape of VNO and PO. A faster evolutionary rate change was observed for PEG; VNO and PO showed similar medium rates and TM showed the slowest evolutionary rate. Our results suggest that allometry and different morphological integration patterns may affect the chemosensory system in studied species. The integration patterns among the shapes of the tongue, the VNO and the PO support the assumed association of the chemical detection system components in Liolaemus lizards.

EU-SENSE detection system in mass gathering evacuation

Current CBRNe detection systems are mainly available as standalone detectors, and seldom offer the potential of networking and data fusion. The research objective is to simulate the scenario-based models built in a virtual environment to examine the possible impact of the EU-SENSE system on chemical detection technology, based on an innovative CBRNe detection and identification system, which is a network of heterogeneous sensor nodes, on the evacuation of a mass gathering. The chemical detection system presents real possibilities of understanding situations that depend on the first symptoms of human health and behaviour. This information will facilitate taking appropriate measures when CBRNe hazard forces to evacuation, including quick identification of the hazard and necessity to modify preliminary evacuation gates (in terms of their localization and width).

Coding Metasurfaces with Reconfiguration Capabilities Based on Optical Activation of Phase‐Change Materials for Terahertz Beam Manipulations

AbstractUltrafast reconfigurable devices with high‐speed responses, high‐resolution capabilities, and ultracompact sizes will be essential for future real‐time terahertz imaging, chemical detection, nondestructive biosensing, and communication systems. Multifunctional terahertz metasurfaces with active, programmable controls have enabled conspicuous functionalities of subwavelength planar devices and components for manipulating electromagnetic (EM) waves such as beam focusing, polarization modification, generation of exotic EM modes, or multibeam scanning applications. However, active metasurface technologies for EM beam manipulation, capable of dynamical topology change, or induced‐phase reconfiguration are usually requiring various semiconductor‐based controlling elements (e.g., PN diodes and transistors), which are difficult to implement in the high‐frequency spectrum of terahertz waves. In this work, a coding metasurface is introduced integrating patterned GeTe phase‐change materials as command elements, which allows the optical control of terahertz wave propagation. The suggested metasurface design brings plentiful of remarkable functionalities through different coding patterns and is highly effective to control beam tilting, directivity, and splitting of terahertz beams. The proposed concepts of coding metasurfaces integrating optically active phase‐change materials are successfully confirmed by experimental demonstration and can be extended to more complex terahertz systems for imaging, tomography, sensing, and 6G communication applications.

Interband Cascade Photonic Integrated Circuits on Native III-V Chip.

We describe how a midwave infrared photonic integrated circuit (PIC) that combines lasers, detectors, passive waveguides, and other optical elements may be constructed on the native GaSb substrate of an interband cascade laser (ICL) structure. The active and passive building blocks may be used, for example, to fabricate an on-chip chemical detection system with a passive sensing waveguide that evanescently couples to an ambient sample gas. A variety of highly compact architectures are described, some of which incorporate both the sensing waveguide and detector into a laser cavity defined by two high-reflectivity cleaved facets. We also describe an edge-emitting laser configuration that optimizes stability by minimizing parasitic feedback from external optical elements, and which can potentially operate with lower drive power than any mid-IR laser now available. While ICL-based PICs processed on GaSb serve to illustrate the various configurations, many of the proposed concepts apply equally to quantum-cascade-laser (QCL)-based PICs processed on InP, and PICs that integrate III-V lasers and detectors on silicon. With mature processing, it should become possible to mass-produce hundreds of individual PICs on the same chip which, when singulated, will realize chemical sensing by an extremely compact and inexpensive package.

Chromo-fluorogenic sensors for chemical warfare agents in real-time analysis: journey towards accurate detection and differentiation.

The existence of chemical weapons (blister and nerve agents) is an unfortunate reality of the modern world. The usage of these chemical agents by rogue states or terrorist groups has showcased their ugly faces in the past and even in recent years. Despite extensive and strenuous efforts by the Organization for the Prohibition of Chemical Weapons (OPCW) to eliminate chemical warfare agents (CWAs) by the prohibition of their production and the destruction of their stockpiles, many countries still possess them in enormous quantities. Given the potential threat from these lethal agents, it is imperative to have a foolproof chemical sensor and detection system, which should consist of readily deployable chemical probes that can operate with high specificity and sensitivity. Over the last decade, our group has been engaged in designing and developing novel field-deployable sensing techniques by exploring approaches based on supramolecular tools, which can result in excellent specificity, sensitivity, high speed, portability and low cost. In this article, I describe our group's journey and success stories in the development of chemical warfare detection protocols, detailing the range of unique chemical probes and methods explored to achieve the specific detection of individual agents under real environmental conditions. It is interesting to note that the combination of three molecular probes (SQ, Fc and LH2) could simply achieve the detection of all CWAs at room temperature in one go without the need for nonportable and expensive instruments. The ease and generality of these techniques/methods suggest great promise for the highly specific chemical sensing of almost the entire class of CWAs. In this paper, a brief introduction is first provided to present the basic chemistry related to CWAs and the importance of supramolecular chemistry in the design of new protocols with new insights. The manipulation of molecular probes is then debated towards the development of a system for the chromo-fluorogenic sensing of CWAs without interference from most relevant analytes. Finally, the outlook of open challenges and the future developments of this rapidly evolving field is discussed.

Covalent organic frameworks as multifunctional materials for chemical detection.

Sensitive and selective detection of chemical and biological analytes is critical in various scientific and technological fields. As an emerging class of multifunctional materials, covalent organic frameworks (COFs) with their unique properties of chemical modularity, large surface area, high stability, low density, and tunable pore sizes and functionalities, which together define their programmable properties, show promise in advancing chemical detection. This review demonstrates the recent progress in chemical detection where COFs constitute an integral component of the achieved function. This review highlights how the unique properties of COFs can be harnessed to develop different types of chemical detection systems based on the principles of chromism, luminescence, electrical transduction, chromatography, spectrometry, and others to achieve highly sensitive and selective detection of various analytes, ranging from gases, volatiles, ions, to biomolecules. The key parameters of detection performance for target analytes are summarized, compared, and analyzed from the perspective of the detection mechanism and structure–property–performance correlations of COFs. Conclusions summarize the current accomplishments and analyze the challenges and limitations that exist for chemical detection under different mechanisms. Perspectives on how future directions of research can advance the COF-based chemical detection through innovation in novel COF design and synthesis, progress in device fabrication, and exploration of novel modes of detection are also discussed.

Research on Reliability of Chemical Power Supply for Lead-Acid Batteries Based on Wide Ambient Temperature Range

This article describes the principles of the use and maintenance of lead-acid battery chemical power supplies for power systems based on a wide range of ambient temperature range, combined with the actual requirements of power systems for the monitoring and maintenance of lead-acid battery chemical power supplies Power supply reliability detection system. The system uses sensor technology and photoelectric coupling technology to collect lead-acid battery data, and determines the operating state of the battery pack by monitoring the battery pack’s single voltage, total voltage, charge and discharge current, and temperature, and innovates to achieve online balance The voltage between the battery and the battery is used to effectively maintain the operation of the battery pack, so that the operating state of the battery pack is easy to observe to minimize the possibility of accidents in the system, and the battery pack is well maintained, thereby increasing the service life of the battery pack, To achieve the purpose of saving resources and environmental protection.

Laser-based long-wave-infrared hyperspectral imaging system for the standoff detection of trace surface chemicals

A trace chemical detector is described that combines external-cavity quantum cascade lasers and a mercury cadmium telluride camera to capture hyperspectral images of the diffuse reflectance from a target surface in the long-wave infrared. The system is able to generate individual hypercubes in <0.1 s. When raster scanning the laser beam over the target surface, areal coverage rates of >60 cm2 / s have been achieved. Results are presented for standoff distances ranging from 0.1 to 25 m. Hyperspectral images generated by the system are analyzed for spectral features that indicate the presence of trace surface contaminants. This approach has been found to be highly capable of detecting trace chemical residues on a wide variety of surfaces, and we present a collection of detection results to demonstrate the capabilities of this technology. Examples include the detection of 10 μg of saccharin powder on a wide range of substrates, 0.2 μg of an explosive residue on a computer keyboard, residual pharmaceuticals within a plastic baggie, and a contaminated fingerprint on cell phone case.

Monte Carlo N-Particle simulations of an underwater chemical threats detection system using neutron activation analysis

In this paper we present Monte Carlo N-Particle (MCNP) simulations of the system for underwater threat detection using neutron activation analysis developed in the SABAT project. The simulated system is based on a D-T neutron generator emitting 14 MeV neutrons without associated α particle detection and equipped with a LaBr3:Ce scintillation detector offering superior energy resolution and allowing for precise identification of activation γ quanta. The performed simulations show that using the neutron activation analysis method with the designed geometry we are able to identify γ-rays from hydrogen, carbon, sulphur and chlorine originating from mustard gas in a sea water environment. Our results show that the most efficient way of mustard gas detection is to compare the integral peak ratio for Cl and H.

Handheld Enzymatic Luminescent Biosensor for Rapid Detection of Heavy Metals in Water Samples

Enzymatic luminescent systems are a promising tool for rapid detection of heavy metals ions for water quality assessment. Nevertheless, their widespread use is limited by the lack of test procedure automation and available sensitive handheld luminometers. Herein we describe integration of disposable microfluidic chips for bioluminescent enzyme-inhibition based assay with a handheld luminometer, which detection system is based on a thermally stabilized silicon photomultiplier (SiPM). Microfluidic chips were made of poly(methyl methacrylate) by micro-milling method and sealed using a solvent bonding technique. The composition of the bioluminescent system in microfluidic chip was optimized to achieve higher luminescence intensity and storage time. Results indicate that developed device provided comparable sensitivity with bench-scale PMT-based commercial luminometers. Limit of detection for copper (II) sulfate reached 2.5 mg/L for developed biosensor. Hereby we proved the concept of handheld enzymatic optical biosensors with disposable chips for bioassay. The proposed biosensor can be used as an early warning field-deployable system for rapid detection of heavy metals salts and other toxic chemicals, which affect bioluminescent signal of enzymatic reaction.

Single-Molecule Detection of DNA in a Nanochannel by High-Field Strength-Assisted Electrical Impedance Spectroscopy.

Many researchers have fabricated micro and nanofluidic devices incorporating optical, chemical, and electrical detection systems with the aim of achieving on-chip analysis of macromolecules. The present study demonstrates a label-free detection of DNA using a nanofluidic device based on impedance measurements that is both sensitive and simple to operate. Using this device, the electrophoresis and dielectrophoresis effect on DNA conformation and the length dependence were examined. A low alternating voltage was applied to the nanogap electrodes to generate a high intensity field (>0.5 MV/m) under non-faradaic conditions. In addition, a 100 nm thick gold electrode was completely embedded in the substrate to allow direct measurements of a solution containing the sample passing through the gap, without any surface modification required. The high intensity field in this device produced a dielectrophoretic force that stretched the DNA molecule across the electrode gap at a specific frequency, based on back and forth movements between the electrodes with the DNA in a random coil conformation. The characteristics of 100 bp, 500 bp, 1 kbp, 5 kbp, 10 kbp, and 48 kbp λ DNA associated with various conformations were quantitatively analyzed with high resolution (on the femtomolar level). The sensitivity of this system was found to be more than about 10 orders of magnitude higher than that obtained from conventional linear alternating current (AC) impedance for the analysis of bio-polymers. This new high-sensitivity process is expected to be advantageous with regard to the study of complex macromolecules and nanoparticles.

Multi-Spectral Quantum Cascade Lasers on Silicon With Integrated Multiplexers

Multi-spectral midwave-infrared (mid-IR) lasers are demonstrated by directly bonding quantum cascade epitaxial gain layers to silicon-on-insulator (SOI) waveguides with arrayed waveguide grating (AWG) multiplexers. Arrays of distributed feedback (DFB) and distributed Bragg-reflection (DBR) quantum cascade lasers (QCLs) emitting at ∼4.7 µm wavelength are coupled to AWGs on the same chip. Low-loss spectral beam combining allows for brightness scaling by coupling the light generated by multiple input QCLs into the fundamental mode of a single output waveguide. Promising results are demonstrated and further improvements are in progress. This device can lead to compact and sensitive chemical detection systems using absorption spectroscopy across a broad spectral range in the mid-IR as well as a high-brightness multi-spectral source for power scaling.

Ion Mobility Spectrometry as a Part of a System for Rapid Detection of Toxic Chemicals

Ion Mobility Spectrometry as a Part of a System for Rapid Detection of Toxic Chemicals

The Design and Test of the Stand-off Surface Chemical Contaminant Detection System based on Raman Spectroscopy

The Design and Test of the Stand-off Surface Chemical Contaminant Detection System based on Raman Spectroscopy