This document describes a wireless sensor network system called Sensors for Automated Control of Coal Dust (SACCD) that can continuously monitor the Total Incombustible Content (TIC) of dust deposited in underground coal mines. The SACCD system uses low-cost wireless sensor modules containing optical, moisture, and mass sensors to measure the TIC of accumulated dust. The sensor data is transmitted via a reliable ad-hoc wireless network. The SACCD system could be used to automatically control rock-dusting equipment and maintain acceptable TIC levels throughout underground coal mines.
This document summarizes a research paper on using a micromechanical cantilever for carbon dioxide gas sensing. It describes how a cantilever coated with zinc oxide can selectively absorb CO2 molecules, changing its mass and resonant frequency. The frequency shift is then used to quantify the amount of CO2 gas present. Fabrication of the cantilever sensor and experimental testing showing the relationship between mass change and frequency shift are discussed. The paper concludes the method provides an original way to measure CO2 gas concentration through absorption-induced changes in the cantilever's resonant properties.
This document summarizes the design and testing of a photonic gas sensor using a silicon strip waveguide to detect carbon dioxide (CO2). Finite element simulations were used to design a strip waveguide with a high evanescent field ratio to enable gas absorption sensing. The sensor was experimentally tested and could detect CO2 concentrations as low as 5000 parts per million, the workplace exposure limit. Measurements matched predictions from the Beer-Lambert law for light absorption, demonstrating the sensor's potential for quantitative gas detection.
Using Time Domain Reflectometry (TDR) to Monitor the Geophysical Properties o...DART Project
This document discusses using Time Domain Reflectometry (TDR) to monitor the geophysical properties of archaeological residues over time. TDR devices were installed at multiple depths and locations, including within and outside of archaeological features, to collect hourly readings on permittivity, conductivity, and temperature. The data collected can help understand contrasts in electromagnetic properties between residues and surrounding soils. Challenges included equipment issues and animal damage. Future work involves further analyzing the data and linking permittivity to soil characteristics measured in a lab. The long-term monitoring provides insights to help detect archaeological sites using geophysical techniques.
This document discusses developments in photon-counting detectors for single-molecule fluorescence microscopy. It describes two common optical configurations used: point-like excitation and detection of freely diffusing molecules, and wide field illumination and detection of surface-immobilized molecules. Each approach currently uses different optimal detectors, but there is room for improvement. Recent developments aim to increase the throughput of single-molecule fluorescence spectroscopy using parallel arrays of single-photon avalanche diodes, and develop large-area photon-counting cameras for fluorescence lifetime imaging at the single-molecule level with sub-nanosecond resolution.
High-accuracy laser spectrometers for wireless trace-gas sensor networksClinton Smith
The document outlines Clinton J. Smith's final public oral exam for his dissertation on developing laser spectrometers for wireless trace gas sensor networks. The dissertation aims to develop CO2 sensors for deployment in a real-time sensor network to monitor carbon fluxes over a broad area. The outline includes development of a wireless laser spectroscopic sensor node for atmospheric CO2 monitoring, quantifying and improving the accuracy of wireless sensor network nodes, developing a solar-powered distributed wireless CO2 monitoring network, techniques for real-time calibration, and conclusions. Laboratory and field tests show the sensors can accurately measure CO2 concentrations with precision below 1% and linear response over large concentration ranges.
Laser-Based Standoff Methane Sensors for Enhancing Coal Miner SafetyClinton Smith
This presentation shows a demonstration of the PSI & Heath Consultants Remote Methane Leak Detector (RMLD) being applied to remote detection of methane within coal mines to supplement existing technology to further enhance coal miner safety.
Luigi Giubbolini | Microwave Nondestructive Testing of Composite MaterialsLuigi Giubbolini
Microwave Nondestructive Testing (MNDT) techniques have advantages over other NDT methods (such as radiography, ultrasonics, and eddy current) regarding low cost, good penetration in nonmetallic materials, good resolution and contactless feature of the microwave sensor (antenna).
This document discusses using functional nanoporous materials for heavy metal sequestration. It describes Self-Assembled Monolayers on Mesoporous Supports (SAMMS) which use high surface area nanoporous substrates coated with tailored organic monolayers for selectively binding heavy metals and radionuclides. SAMMS provides high capacity, fast sorption kinetics, and chemical specificity that can be modified for different targets through the monolayer interface. New classes of functional nanoporous materials like mesoporous metal phosphates and carbons also show promise for heavy metal capture.
This document summarizes a research paper on using a micromechanical cantilever for carbon dioxide gas sensing. It describes how a cantilever coated with zinc oxide can selectively absorb CO2 molecules, changing its mass and resonant frequency. The frequency shift is then used to quantify the amount of CO2 gas present. Fabrication of the cantilever sensor and experimental testing showing the relationship between mass change and frequency shift are discussed. The paper concludes the method provides an original way to measure CO2 gas concentration through absorption-induced changes in the cantilever's resonant properties.
This document summarizes the design and testing of a photonic gas sensor using a silicon strip waveguide to detect carbon dioxide (CO2). Finite element simulations were used to design a strip waveguide with a high evanescent field ratio to enable gas absorption sensing. The sensor was experimentally tested and could detect CO2 concentrations as low as 5000 parts per million, the workplace exposure limit. Measurements matched predictions from the Beer-Lambert law for light absorption, demonstrating the sensor's potential for quantitative gas detection.
Using Time Domain Reflectometry (TDR) to Monitor the Geophysical Properties o...DART Project
This document discusses using Time Domain Reflectometry (TDR) to monitor the geophysical properties of archaeological residues over time. TDR devices were installed at multiple depths and locations, including within and outside of archaeological features, to collect hourly readings on permittivity, conductivity, and temperature. The data collected can help understand contrasts in electromagnetic properties between residues and surrounding soils. Challenges included equipment issues and animal damage. Future work involves further analyzing the data and linking permittivity to soil characteristics measured in a lab. The long-term monitoring provides insights to help detect archaeological sites using geophysical techniques.
This document discusses developments in photon-counting detectors for single-molecule fluorescence microscopy. It describes two common optical configurations used: point-like excitation and detection of freely diffusing molecules, and wide field illumination and detection of surface-immobilized molecules. Each approach currently uses different optimal detectors, but there is room for improvement. Recent developments aim to increase the throughput of single-molecule fluorescence spectroscopy using parallel arrays of single-photon avalanche diodes, and develop large-area photon-counting cameras for fluorescence lifetime imaging at the single-molecule level with sub-nanosecond resolution.
High-accuracy laser spectrometers for wireless trace-gas sensor networksClinton Smith
The document outlines Clinton J. Smith's final public oral exam for his dissertation on developing laser spectrometers for wireless trace gas sensor networks. The dissertation aims to develop CO2 sensors for deployment in a real-time sensor network to monitor carbon fluxes over a broad area. The outline includes development of a wireless laser spectroscopic sensor node for atmospheric CO2 monitoring, quantifying and improving the accuracy of wireless sensor network nodes, developing a solar-powered distributed wireless CO2 monitoring network, techniques for real-time calibration, and conclusions. Laboratory and field tests show the sensors can accurately measure CO2 concentrations with precision below 1% and linear response over large concentration ranges.
Laser-Based Standoff Methane Sensors for Enhancing Coal Miner SafetyClinton Smith
This presentation shows a demonstration of the PSI & Heath Consultants Remote Methane Leak Detector (RMLD) being applied to remote detection of methane within coal mines to supplement existing technology to further enhance coal miner safety.
Luigi Giubbolini | Microwave Nondestructive Testing of Composite MaterialsLuigi Giubbolini
Microwave Nondestructive Testing (MNDT) techniques have advantages over other NDT methods (such as radiography, ultrasonics, and eddy current) regarding low cost, good penetration in nonmetallic materials, good resolution and contactless feature of the microwave sensor (antenna).
This document discusses using functional nanoporous materials for heavy metal sequestration. It describes Self-Assembled Monolayers on Mesoporous Supports (SAMMS) which use high surface area nanoporous substrates coated with tailored organic monolayers for selectively binding heavy metals and radionuclides. SAMMS provides high capacity, fast sorption kinetics, and chemical specificity that can be modified for different targets through the monolayer interface. New classes of functional nanoporous materials like mesoporous metal phosphates and carbons also show promise for heavy metal capture.
Controlled Source Electromagnetic Survey for Seabed Mineral ExplorationGuanren Wang
1) The document discusses using controlled source electromagnetic (CSEM) surveys to detect submarine massive sulfide (SMS) deposits at the Trans-Atlantic Geotraverse (TAG) hydrothermal field.
2) 1D and 2D forward modelling was conducted to determine optimal acquisition parameters for a deep-towed CSEM survey, including frequencies of 0.5-5 Hz, tow heights over 100m, and offsets large enough to detect thicker, more conductive SMS layers.
3) 2D modelling showed phase divergence between SMS and background models could indicate exceptionally conductive zones or thicker conductive layers within SMS mounds. Frequencies of 0.5-5 Hz were determined to be most beneficial for detecting thicker,
FT-NIR as a real-time QC tool for polymer manufacturingGalaxy Scientific
Near infrared spectroscopy has been used widely in the polymer industry. Compared to traditional methods such as wet chemistry and chromatographic methods, NIR spectroscopy provides considerable advantages in process and quality control applications through fundamental benefits such as low to no cost of consumables such as solvents, columns, reagents; real time analysis - generally less than 10 seconds measurement time; multiple components per analysis; elimination of sample preparation time; and elimination of many sources of systematic error.
This presentation will present three FT-NIR polymer applications: 1) at line polyether polyols’ hydroxyl value analysis; 2) real time isocyanate number monitoring during a polyurethane reaction; and 3) off-line quality control of percentage styrene in styrene copolymers.
- The document discusses testing the absorbance spectra of lanthanide ions like Nd3+ and Tm3+ in liquid solvents versus glass hosts to potentially model rare earth doping in liquids instead of expensive glass fibers.
- Absorbance spectra were taken of Nd3+ in water, methanol, and a glass (Ca3Ga2Ge3O12) and showed similar peak profiles but a blueshift of peaks in the solvents compared to the glass.
- Software was developed to analyze spectroscopy data from this work and future studies on lanthanide absorbance and emission characteristics to determine if liquid testing could replicate behaviors in glass fibers.
This document describes research on using a photonic crystal fiber sensor to detect monoclonal antibodies (mAbs) in aqueous solution. A 0.8m photonic crystal fiber was exposed to a 3.74nL sample of purified human IgG at a concentration of 0.1mol/mL. Absorption spectroscopy analysis from 1300-1700nm detected absorption peaks specific to the mAbs at 1430nm and 1540nm, indicating label-free detection is possible. The sensor response time was under 30 seconds, much faster than standard detection methods. Future work will optimize sensitivity by varying parameters like concentration, temperature, and interaction length.
This document discusses the application of near infrared reflectance spectroscopy (NIRS) in the feed industry. NIRS is a rapid, nondestructive technique used to determine the protein, moisture, starch, lipid, and ash content of feed ingredients. It has been accepted as an official method for analyzing crude protein, acid detergent fiber, and moisture in feeds. NIRS can also be used to detect heat damaged proteins, fungal contamination, and adulteration in feeds. Calibrations are developed using statistical methods to relate NIR spectra to wet chemistry values. NIRS offers advantages such as rapid analysis, little to no sample preparation, simultaneous analysis of multiple components, and environmental friendliness.
1) Quantum cascade lasers can be used as sensing platforms to detect targeted molecules like gases and liquids through optical absorption of their vibrational frequencies in the near- and mid-infrared ranges.
2) The document discusses applications of quantum cascade lasers for optical sensing of gases, including human breath analysis and detection of helicobacter pylori. It provides examples of sensitive gas detection using INFN instrumentation, such as methane (sensitivity of 7.3-8.06 μm at 0.8 ppb) and nitrous oxide (sensitivity of 7.8 μm at 0.8 ppb).
3) Methods to upconvert quantum cascade laser signals to the visible range using techniques like second harmonic generation or Er
Characterization of Liquid Waste in Isotope production and Research Facilitiesiosrjce
IOSR Journal of Applied Physics (IOSR-JAP) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of physics and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in applied physics. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Infrared absorption spectroscopy can be used to analyze both organic and inorganic compounds. It utilizes three infrared regions - near, mid, and far infrared. The document discusses the instrumentation used in infrared spectroscopy, including infrared radiation sources, monochromators, sample cells, and detectors. It also covers sample preparation techniques for solids, liquids, and gases. Infrared spectroscopy has various applications such as quality control, forensic analysis, polymer analysis, and semiconductor analysis.
This document discusses the nonlinear optical properties of copper nanoparticles prepared by pulse laser ablation in different solutions. Copper nanoparticles were synthesized in distilled water, deionized water, and a mixture of ethylene glycol and deionized water using a nanosecond pulsed Nd:YAG laser. Characterization using UV-visible spectroscopy and SEM showed the nanoparticles had surface plasmon resonance peaks between 590-676 nm and diameters ranging from 13.16-21.25 nm depending on the solution. Z-scan measurements determined the nonlinear refractive index and nonlinear absorption coefficient of the copper nanoparticle suspensions.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Evaluation of near infrared (NIR) spectroscopy as a tool for determination of...SLOPE Project
This document summarizes a task to evaluate near infrared (NIR) spectroscopy for determining log and biomass quality in mountain forests. Several organizations will work together on the task, led by CNR. CNR will coordinate, evaluate NIR spectroscopy along the harvesting chain, and develop a "NIR quality index." Boku will support CNR with lab measurements and calibration transfer. Other partners will help collect NIR spectra in the field. The objectives are to evaluate NIR spectroscopy for characterizing resources along the harvesting chain and provide guidelines for collection and analysis of NIR spectra. Activities will include feasibility studies, developing chemometric models to predict quality indicators from spectra, and transferring calibrations between lab and portable instruments. Del
Quality Measurements Using NIR/MIR Spectroscopy: A Rotten Apple Could Turn Yo...TechRentals
Light interacts with a product's organic molecules causing variations in light absorption. The transmitted or reflected light can be measured with a spectrometer and the resultant spectral signature used to qualify or quantify properties of the product. The discussion will include - how light interacts with molecules, characteristics of the different electromagnetic spectral bands, in-line hardware required to collect light, and fundamentals of chemometrics.
Presenter -- Gary Brown
Gary Brown is one of the principle engineers with Australian Innovative Engineering and has spent the last 12+ years developing in-line instrumentation using NIR spectroscopy to measure properties of fresh fruit. He is now concentrating his efforts in applying the technology for in-line product authentication for the food and pharmaceutical industries.
This document discusses using passive open-path Fourier transform infrared (OP-FTIR) spectroscopy to monitor pesticide drift. The researchers conducted greenhouse and outdoor experiments to detect and quantify pesticide clouds using OP-FTIR. In the greenhouse experiments, the OP-FTIR was able to successfully detect water clouds 94.8% of the time with a 5% false positive rate. Outdoor experiments detected pesticide clouds created by common sprayers. Future work will incorporate radiative transfer modeling to estimate cloud parameters like concentration from the OP-FTIR measurements.
RESONANCE BASED MICROMECHANICAL CANTILEVER FOR GAS SENSINGIJNSA Journal
Our world is facing some drastic changes in the climatic conditions due to the heating effect caused by various greenhouse gases. The most harmful gas among them is Carbon dioxide and is increasing at an uncontrolled rate.
This paper aims in finding out the quantity of the major polluting gas carbon dioxide. The gravimetric sensor works by adsorbing the CO2 molecules on ZnO sensing layer, which alters the overall mass of the sensor. The mechanical structure is a cantilever, having its own resonant frequency. To selectively adsorb CO2 molecules from the mixture of gaseous molecules, ZnO at a specific temperature is used. As the gas molecules are adsorbed the mass increases and hence there is a change in resonant frequency. This change in frequency gives the measure of the quantity of CO2 molecules present in that environment. The major expected advantage of this technique would be the repeatability of the sensor that is used. This Quantitative analysis of CO2 would be helpful for mankind by alerting them about the environment in which they work, by proper conditioning and networking.
The document summarizes a summer training report on the characterization of 8 mole% yttria stabilized zirconia obtained from different sources. The objectives were to characterize and compare YSZ powders from ISRO, IRE and TOSOH, and to optimize sintering conditions to achieve high density pellets suitable for use as a solid oxide fuel cell electrolyte. Characterization techniques included tap density measurement, BET surface area analysis, X-ray diffraction for phase analysis, particle size distribution analysis, and density measurement of sintered pellets.
Anderson_et_al-2016-Advanced_Materials_InterfacesSam Anderson
This document describes a method for coating cotton fabric with silver and copper nanoparticles using an electroless deposition process, resulting in fabrics (Cu@Cotton and Ag@Cotton) with localized surface plasmon resonance properties. Scanning electron microscopy images show the deposition of quasi-spherical copper and silver nanoparticles onto individual cotton threads. The coated fabrics are investigated for their potential in visible light-activated catalytic applications by studying the electron transfer processes during a model reaction under illumination, providing insight into how light can enhance catalysis at metal surfaces.
The document discusses the use of optical fiber sensors for non-destructive testing applications. It notes that fiber optic sensors are well-suited for structural health monitoring due to their small size, light weight, and immunity to electromagnetic interference. The document outlines different types of fiber optic sensors and their advantages over conventional sensors. It also provides examples of how fiber optic sensors can be embedded in composite materials and structures to monitor factors like temperature, pressure, and strain for non-destructive testing.
Application of Seismic Reflection Surveys to Detect Massive Sulphide Deposits...iosrjce
Seismic reflection techniques, the most widely used geophysical method for hydrocarbon exploration
has the capability to delineate and provide better images of regional structure for exploration of mineral
deposits in any geological settings. Previous tests on detection and imaging of massive sulphide ores using
seismic reflection techniques have been done mostly in crystalline environments. Application of seismic
reflection techniques for imaging sedimentary hosted massive sulphide is relatively new and the few experiments
carried out are at local scale (<500m). In this study, we analyze the feasibility of such regional exploration by
modelling three massive sulphide ore and norite lenses scenario using 2D seismic survey with relatively sparse
source-receiver geometry to image these deposits within 1.5km depth range. Results from the modelling
experiment demonstrate that 2-Dimensional seismic reflections survey can be used to detect massive sulphides
at any scale. The test further indicates that geologic setting and acquisition parameters are very important for
the detection of these ore bodies. Overall, the outcomes of the results support our started objective which is to
demonstrate that seismic reflection surveys can be used to detect the presence of sediment hosted massive
sulphides at regional scale
Fabrication of microfluidic channels in glass and siliconYichen Sun
Microfluidic channels in glass and silicon chips are fabricated in the cleanroom. Their acoustic focusing properties are then tested and reported in this project report (MEMS 5801).
Iaetsd review on significance of piezoelectric materIaetsd Iaetsd
This document discusses the design and simulation of a MEMS-based surface acoustic wave (SAW) gas sensor. SAW gas sensors use piezoelectric materials and operate by detecting changes in oscillation frequency when gas molecules are absorbed by a sensing film on the surface. The document describes modeling the sensor geometry and materials in COMSOL Multiphysics to simulate sensor performance. Simulations analyzed deformation and electrical potential at resonance and anti-resonance frequencies for different piezoelectric materials. Results showed lithium tantalate produced better responses than lithium niobate. SAW gas sensors are widely used to detect gases for applications like vehicle emissions monitoring.
Controlled Source Electromagnetic Survey for Seabed Mineral ExplorationGuanren Wang
1) The document discusses using controlled source electromagnetic (CSEM) surveys to detect submarine massive sulfide (SMS) deposits at the Trans-Atlantic Geotraverse (TAG) hydrothermal field.
2) 1D and 2D forward modelling was conducted to determine optimal acquisition parameters for a deep-towed CSEM survey, including frequencies of 0.5-5 Hz, tow heights over 100m, and offsets large enough to detect thicker, more conductive SMS layers.
3) 2D modelling showed phase divergence between SMS and background models could indicate exceptionally conductive zones or thicker conductive layers within SMS mounds. Frequencies of 0.5-5 Hz were determined to be most beneficial for detecting thicker,
FT-NIR as a real-time QC tool for polymer manufacturingGalaxy Scientific
Near infrared spectroscopy has been used widely in the polymer industry. Compared to traditional methods such as wet chemistry and chromatographic methods, NIR spectroscopy provides considerable advantages in process and quality control applications through fundamental benefits such as low to no cost of consumables such as solvents, columns, reagents; real time analysis - generally less than 10 seconds measurement time; multiple components per analysis; elimination of sample preparation time; and elimination of many sources of systematic error.
This presentation will present three FT-NIR polymer applications: 1) at line polyether polyols’ hydroxyl value analysis; 2) real time isocyanate number monitoring during a polyurethane reaction; and 3) off-line quality control of percentage styrene in styrene copolymers.
- The document discusses testing the absorbance spectra of lanthanide ions like Nd3+ and Tm3+ in liquid solvents versus glass hosts to potentially model rare earth doping in liquids instead of expensive glass fibers.
- Absorbance spectra were taken of Nd3+ in water, methanol, and a glass (Ca3Ga2Ge3O12) and showed similar peak profiles but a blueshift of peaks in the solvents compared to the glass.
- Software was developed to analyze spectroscopy data from this work and future studies on lanthanide absorbance and emission characteristics to determine if liquid testing could replicate behaviors in glass fibers.
This document describes research on using a photonic crystal fiber sensor to detect monoclonal antibodies (mAbs) in aqueous solution. A 0.8m photonic crystal fiber was exposed to a 3.74nL sample of purified human IgG at a concentration of 0.1mol/mL. Absorption spectroscopy analysis from 1300-1700nm detected absorption peaks specific to the mAbs at 1430nm and 1540nm, indicating label-free detection is possible. The sensor response time was under 30 seconds, much faster than standard detection methods. Future work will optimize sensitivity by varying parameters like concentration, temperature, and interaction length.
This document discusses the application of near infrared reflectance spectroscopy (NIRS) in the feed industry. NIRS is a rapid, nondestructive technique used to determine the protein, moisture, starch, lipid, and ash content of feed ingredients. It has been accepted as an official method for analyzing crude protein, acid detergent fiber, and moisture in feeds. NIRS can also be used to detect heat damaged proteins, fungal contamination, and adulteration in feeds. Calibrations are developed using statistical methods to relate NIR spectra to wet chemistry values. NIRS offers advantages such as rapid analysis, little to no sample preparation, simultaneous analysis of multiple components, and environmental friendliness.
1) Quantum cascade lasers can be used as sensing platforms to detect targeted molecules like gases and liquids through optical absorption of their vibrational frequencies in the near- and mid-infrared ranges.
2) The document discusses applications of quantum cascade lasers for optical sensing of gases, including human breath analysis and detection of helicobacter pylori. It provides examples of sensitive gas detection using INFN instrumentation, such as methane (sensitivity of 7.3-8.06 μm at 0.8 ppb) and nitrous oxide (sensitivity of 7.8 μm at 0.8 ppb).
3) Methods to upconvert quantum cascade laser signals to the visible range using techniques like second harmonic generation or Er
Characterization of Liquid Waste in Isotope production and Research Facilitiesiosrjce
IOSR Journal of Applied Physics (IOSR-JAP) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of physics and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in applied physics. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Infrared absorption spectroscopy can be used to analyze both organic and inorganic compounds. It utilizes three infrared regions - near, mid, and far infrared. The document discusses the instrumentation used in infrared spectroscopy, including infrared radiation sources, monochromators, sample cells, and detectors. It also covers sample preparation techniques for solids, liquids, and gases. Infrared spectroscopy has various applications such as quality control, forensic analysis, polymer analysis, and semiconductor analysis.
This document discusses the nonlinear optical properties of copper nanoparticles prepared by pulse laser ablation in different solutions. Copper nanoparticles were synthesized in distilled water, deionized water, and a mixture of ethylene glycol and deionized water using a nanosecond pulsed Nd:YAG laser. Characterization using UV-visible spectroscopy and SEM showed the nanoparticles had surface plasmon resonance peaks between 590-676 nm and diameters ranging from 13.16-21.25 nm depending on the solution. Z-scan measurements determined the nonlinear refractive index and nonlinear absorption coefficient of the copper nanoparticle suspensions.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Evaluation of near infrared (NIR) spectroscopy as a tool for determination of...SLOPE Project
This document summarizes a task to evaluate near infrared (NIR) spectroscopy for determining log and biomass quality in mountain forests. Several organizations will work together on the task, led by CNR. CNR will coordinate, evaluate NIR spectroscopy along the harvesting chain, and develop a "NIR quality index." Boku will support CNR with lab measurements and calibration transfer. Other partners will help collect NIR spectra in the field. The objectives are to evaluate NIR spectroscopy for characterizing resources along the harvesting chain and provide guidelines for collection and analysis of NIR spectra. Activities will include feasibility studies, developing chemometric models to predict quality indicators from spectra, and transferring calibrations between lab and portable instruments. Del
Quality Measurements Using NIR/MIR Spectroscopy: A Rotten Apple Could Turn Yo...TechRentals
Light interacts with a product's organic molecules causing variations in light absorption. The transmitted or reflected light can be measured with a spectrometer and the resultant spectral signature used to qualify or quantify properties of the product. The discussion will include - how light interacts with molecules, characteristics of the different electromagnetic spectral bands, in-line hardware required to collect light, and fundamentals of chemometrics.
Presenter -- Gary Brown
Gary Brown is one of the principle engineers with Australian Innovative Engineering and has spent the last 12+ years developing in-line instrumentation using NIR spectroscopy to measure properties of fresh fruit. He is now concentrating his efforts in applying the technology for in-line product authentication for the food and pharmaceutical industries.
This document discusses using passive open-path Fourier transform infrared (OP-FTIR) spectroscopy to monitor pesticide drift. The researchers conducted greenhouse and outdoor experiments to detect and quantify pesticide clouds using OP-FTIR. In the greenhouse experiments, the OP-FTIR was able to successfully detect water clouds 94.8% of the time with a 5% false positive rate. Outdoor experiments detected pesticide clouds created by common sprayers. Future work will incorporate radiative transfer modeling to estimate cloud parameters like concentration from the OP-FTIR measurements.
RESONANCE BASED MICROMECHANICAL CANTILEVER FOR GAS SENSINGIJNSA Journal
Our world is facing some drastic changes in the climatic conditions due to the heating effect caused by various greenhouse gases. The most harmful gas among them is Carbon dioxide and is increasing at an uncontrolled rate.
This paper aims in finding out the quantity of the major polluting gas carbon dioxide. The gravimetric sensor works by adsorbing the CO2 molecules on ZnO sensing layer, which alters the overall mass of the sensor. The mechanical structure is a cantilever, having its own resonant frequency. To selectively adsorb CO2 molecules from the mixture of gaseous molecules, ZnO at a specific temperature is used. As the gas molecules are adsorbed the mass increases and hence there is a change in resonant frequency. This change in frequency gives the measure of the quantity of CO2 molecules present in that environment. The major expected advantage of this technique would be the repeatability of the sensor that is used. This Quantitative analysis of CO2 would be helpful for mankind by alerting them about the environment in which they work, by proper conditioning and networking.
The document summarizes a summer training report on the characterization of 8 mole% yttria stabilized zirconia obtained from different sources. The objectives were to characterize and compare YSZ powders from ISRO, IRE and TOSOH, and to optimize sintering conditions to achieve high density pellets suitable for use as a solid oxide fuel cell electrolyte. Characterization techniques included tap density measurement, BET surface area analysis, X-ray diffraction for phase analysis, particle size distribution analysis, and density measurement of sintered pellets.
Anderson_et_al-2016-Advanced_Materials_InterfacesSam Anderson
This document describes a method for coating cotton fabric with silver and copper nanoparticles using an electroless deposition process, resulting in fabrics (Cu@Cotton and Ag@Cotton) with localized surface plasmon resonance properties. Scanning electron microscopy images show the deposition of quasi-spherical copper and silver nanoparticles onto individual cotton threads. The coated fabrics are investigated for their potential in visible light-activated catalytic applications by studying the electron transfer processes during a model reaction under illumination, providing insight into how light can enhance catalysis at metal surfaces.
The document discusses the use of optical fiber sensors for non-destructive testing applications. It notes that fiber optic sensors are well-suited for structural health monitoring due to their small size, light weight, and immunity to electromagnetic interference. The document outlines different types of fiber optic sensors and their advantages over conventional sensors. It also provides examples of how fiber optic sensors can be embedded in composite materials and structures to monitor factors like temperature, pressure, and strain for non-destructive testing.
Application of Seismic Reflection Surveys to Detect Massive Sulphide Deposits...iosrjce
Seismic reflection techniques, the most widely used geophysical method for hydrocarbon exploration
has the capability to delineate and provide better images of regional structure for exploration of mineral
deposits in any geological settings. Previous tests on detection and imaging of massive sulphide ores using
seismic reflection techniques have been done mostly in crystalline environments. Application of seismic
reflection techniques for imaging sedimentary hosted massive sulphide is relatively new and the few experiments
carried out are at local scale (<500m). In this study, we analyze the feasibility of such regional exploration by
modelling three massive sulphide ore and norite lenses scenario using 2D seismic survey with relatively sparse
source-receiver geometry to image these deposits within 1.5km depth range. Results from the modelling
experiment demonstrate that 2-Dimensional seismic reflections survey can be used to detect massive sulphides
at any scale. The test further indicates that geologic setting and acquisition parameters are very important for
the detection of these ore bodies. Overall, the outcomes of the results support our started objective which is to
demonstrate that seismic reflection surveys can be used to detect the presence of sediment hosted massive
sulphides at regional scale
Fabrication of microfluidic channels in glass and siliconYichen Sun
Microfluidic channels in glass and silicon chips are fabricated in the cleanroom. Their acoustic focusing properties are then tested and reported in this project report (MEMS 5801).
Iaetsd review on significance of piezoelectric materIaetsd Iaetsd
This document discusses the design and simulation of a MEMS-based surface acoustic wave (SAW) gas sensor. SAW gas sensors use piezoelectric materials and operate by detecting changes in oscillation frequency when gas molecules are absorbed by a sensing film on the surface. The document describes modeling the sensor geometry and materials in COMSOL Multiphysics to simulate sensor performance. Simulations analyzed deformation and electrical potential at resonance and anti-resonance frequencies for different piezoelectric materials. Results showed lithium tantalate produced better responses than lithium niobate. SAW gas sensors are widely used to detect gases for applications like vehicle emissions monitoring.
The document describes a new humidity sensor developed using graphene quantum dots (GQDs) synthesized from citric acid. The sensor exhibited high sensitivity to changes in relative humidity over a wide range from 0% to 97%. The sensor response decreased as humidity increased, unlike previous GQD sensors, suggesting a different sensing mechanism. The sensor response time was about 10 seconds while recovery time was longer, especially for larger humidity changes. The sensor demonstrated good repeatability, durability, and negligible hysteresis.
Experimental study of gas flux characteristics in a co2 selective silica base...IAEME Publication
1. The document describes an experimental study of gas flux characteristics in a CO2 selective silica-based ceramic membrane.
2. A fresh ceramic membrane was prepared using a sol-gel dip coating technique and tested for separating CO2, O2, CH4, and N2 gases.
3. Results showed the membrane had high CO2 flux and CO2/N2 selectivity, confirming its potential for CO2 capture from flue gases. The gas flux increased linearly with pressure.
A REVIEW OF VARIOUS SOIL MOISTUREMEASUREMENT TECHNIQUESBhushan Patil
This paper presents review of the different eight methods for measurement of soil moisture and describes the principle used, methodology, advantages, disadvantages and comparison. Described methods are Gravimetric method, Neutron moderation (NM), Time Domain Reflectometer (TDR), Frequency Domain Reflectometer (FDR), Amplitude Domain Reflectometer (ADR), Phase Transmission (PT), Time Domain Transmission (TDT) and Tensiometer method.
The document summarizes research on using nanoparticles to improve gas sensor performance. It discusses how reducing metal oxide particles sizes to the nanoscale can dramatically increase their surface area and gas detection sensitivity, selectivity, and response time. The researcher has developed gas sensor prototypes using various metal oxide nanomaterials deposited as thick films or multilayer structures. Nanofabrication methods are also being explored to create high surface area sensor platforms using anodic aluminum oxide templates. Overall, the research aims to leverage nanotechnology to develop lower cost, higher performance gas sensors for industrial and environmental monitoring applications.
Optimization of light source wavelength for ammonia detection in waterTELKOMNIKA JOURNAL
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International Journal of Engineering and Science Invention (IJESI)
Mahdavipour_Sensors_2015_Final_1641
1. Wireless Sensors for Automated Control of Total
Incombustible Content (TIC) of Dust Deposited in
Underground Coal Mines
Omid Mahdavipour1
, Timothy Mueller-Sim1
, Dorsa Fahimi1
, Skot Croshere2
, Pit Pillatsch2
, Jusuf Merukh2
, Valentino Zegna
Baruffa1
, John Sabino1
, Koji Tran1
, Giovanni Alanis1
, Paul Solomon3
, Paul Wright2
, Richard M. White2
, Lara Gundel4
, and Igor
Paprotny1+
1
Department of Electrical and Computer Engineering, University of Illinois, Chicago, IL
2
University of California, Berkley, CA
3
U.S. Environmental Protection Agency, Las Vegas, NV
4
Lawrence Berkeley National Laboratory, Berkeley, CA
+
paprotny@uic.edu
Abstract— This paper presents a low-cost/low-power
wirelessly enabled distributed sensing system that can be placed
throughout underground coal mines to continuously measure
the total incombustible content (TIC) of the deposited dust.
Underground coal mining operations produce finely divided
coal dust, called float dust, which deposits throughout the mine.
This combustible material can be feedstock for coal dust
explosions. In U.S., MSHA standard 23789 dictates that a TIC
of 80% or above has to be maintained in coal mine return
airways. However, current best practices for collecting TIC
involve manual sampling and laboratory procedures. In this
work, we describe a new wireless sensor network (WSN)
consisting of low-cost/low-power sensor modules that use a
variety of optical and microfabricated sensors to continuously
monitor the TIC of the accumulated dust. The information is
then transmitted off-board through a reliable ad-hoc wireless
network. Called Sensors for Automated Control of Coal Dust
(SACCD), this system can, for example, be used to automate
the control of rock-dusting equipment to maintain TIC at
acceptable levels.
Keywords—Float Dust, Wireless Sensor Networks, Total
Incombustible Content
I. INTRODUCTION
Underground coal mining operations produce finely divided
coal dust, called float dust that deposits throughout operating
coal mines. This combustible material can be feedstock for coal
dust explosions, and current mining operations produce finer
and more easily combustible particles than operations in the
early twentieth century [1]. Limestone powder, known as rock
dust, is used widely as an inerting agent, and mine safety
regulations specify minimal total incombustible content (TIC)
for both intake and return airways. These limits ensure that the
dispersed coal dust-rock dust mixture will not propagate a
flame in air.
To detect the TIC, several optical methods have been
developed, such as the Optical Dust Deposition Meter
(ODDM) [2] and the Coal Dust Explosibility Meter (CDEM)
[3] for assessing the TIC of coal and rock dust mixtures
deposited on surfaces of underground mines. These devices,
although effective, are quite labor intensive and depend on
moisture content of the mixture.
II. SENSING ELEMENT DESIGN
The SACCD consists of an optical dust reflectance-based
sensor, a microfabricated moisture sensor, and MEMS mass
sensors. A close-up partial cutaway rendering of the sensing
elements of the SACCD prototype is shown on Fig 1.
A. Optical Float Dust Deposition Sensor
The operation of the optical dust deposition sensor is based on
the difference in optical reflectivity of coal (black and low
reflectivity) and rock dust (white and highly reflective). The
optical dust deposition sensor determines the surface loading
density of a dust layer by measuring its optical reflectivity. The
degree of combustion hazard associated with float coal dust is
related to the surface density of the deposited coal dust.
This project is supported by a grant from the Center for Disease Control
and Prevention (CDC)/ National Institute of Occupational Safety and Health
(NIOSH), contract# 200-2013-57155.
Figure 1: Partial cut-away CAD drawing of the sensor module indicating
(a) probing optical transmitters, (b) calibration detector, (c) reference
transmitter, (d) investigation detector, (e) reference detector, (f) quartz polka
dot beam splitter, (g) clear quartz window, (h) microfabricated interdigitated
capacitive moisture sensor, and (i) MEMS capacitive mass sensor.
2. The mathematical expressions for the normalized optical
reflectivity for a layer of coal (rock) dust deposited over an
optically thick layer of rock (coal) dust Φcd (Φrd) are given by
[3],
Φ (1)
Φ 1 (2)
Where σcd and σrd are surface loading of coal and rock dust
respectively in mg/cm2
. Also αcd and αrd are the attenuation
coefficient associated with coal and rock dust respectively. The
attenuation coefficient is a function of the optical characteristics
of the individual particles and the particle size distribution.
Fig. 1 shows the optical dust deposition sensor setup which
consists of a probing infrared LED (a) light source, and an
infrared phototransistor detector (d) to measure the reflectance
from the mixture of coal and rock dust. To compensate for the
change in intensity of the probing transmitter, the light beam is
split using the microfabricated perforated beam splitter
depicted in Fig. 2 and the intensity of the reflected part of the
beam is measured using the calibration detector (c).
In addition to the interrogating beam, the reference beam (c)
that crosses the optical detector (without interrogating the
accumulated dust stack) provides reference data to track time-
dependent changes of the beam intensity. In order to protect and
counteract the fouling of the optics due to dust accumulation,
we applied a hydrophobic coating to the quartz windows on
both sides of the optical detector.
B. Interdigitated Dielectrometry Moisture Sensor
The optical dust deposition sensor determines the mixture’s
TIC by measuring the mixture’s near-infrared reflectivity.
Surface reflectivity is also a function of the unbound moisture
content of the mixture. To accurately measure the mixture’s
TIC, it is necessary to determine the amount of moisture present
and correct for its presence to avoid the need for removing (and
drying) the moisture before the measurement.
One of the most effective indirect nondestructive means for
examination of moisture content of the material under test is
dielectrometry. Interdigital dielectrometry sensors use fringing
electrical field between the electrodes to probe the material
under the test. These sensors fringing field sensor does not
require two-sided access to the MUT, unlike the parallel-plate
sensors. Fringing electric field lines pass through the MUT; as
a result, the capacitance and conductance between the two
electrodes depends on the material dielectric properties as well
as on the electrode and material geometry. The penetration
depth of the fringing electric fields above the interdigital
electrodes is proportional to the spacing between the centerlines
of the sensing and the driven fingers [5].
To be able to probe a 1 mm thick mixture, the interdigitated
sensor with spatial wavelength of 1 mm is designed and
microfabricated by lithography patterning of an aluminum
coated quartz wafer. Fig. 3 shows the design of the
interdigitated moisture sensor as well as the results from finite
element modeling of the sensor.
C. Capacitive Mass Sensor
Due to the open structure and real-time nature of the SACCD,
in which the system is continuously recording the accumulating
dust layer, the surface of sensor is expected to accumulate
substantial amounts of float and rock dust. In order to measure
the mass and gain additional information about whether rock or
float dust is accumulating, as well as identify the level of
accumulation for reconditioning /cleaning off the accumulated
dust, a mass sensor that weighs the accumulating stack is
needed.
The new mass sensor uses a modified design based on this
group’s previously fabricated MEMS capacitive in-line flow
sensors [4]. The mass sensor uses displacement of a paddle
caused by the weight of the deposited coal and rock dust to
induce capacitance change between two ports of the sensor.
Simplicity of fabrication, low operating voltage (leading to an
intrinsically safe design) combined with insensitivity to
Figure 2: Microfabricated perforated (also known as Polka-Dot)
beamsplitter fabricated by lithography patterning of deposited aluminuim
coating on quartz wafer. The beamsplitter is designed to 50:50 transmission
to reflection ratio.
Figure 3: FEM modeled output capacitance between the drive and sense
electrodes versus the moisture content of the coal dust. The insert shows
the electrical field and potential distribution. The top-left insert is a macro
image of the microfabricated moisture sensor wire-bonded to PCB
substrate.
100µm
180µm
2mm
3. variations in ambient temperature, make this sensor ideal for
widespread deployment monitor in underground coal mines.
Fig. 4 is a macro image picture of the MEMS capacitive mass
sensor, fabricated using MEMS Silicon-On- Insulator (SOI)
technology. A paddle supported by two cantilevers deflects out-
of-plane under the weight of the mixture of rock and coal dust.
Variable comb drive capacitors with movable electrodes
attached to the paddle change capacitance as the structure is
deflected. By measuring the change of the capacitance, the
weight, and as a result, mass, of stack can be calculated.
Assuming 70-um SOI thickness, the capacitance changes about
0.14 pF for 10-mg dust mass deposition on the paddle. Fig. 5
shows numerical modeling results for change in the capacitance
of the mass-sensor versus amount of the mass added to the
sensor.
III. CUMMINUICATIONS AND NETWORK
The hardware platform for the wireless mesh network has been
selected as the Xbee DigiMesh network [6]. This platform
provides safe networking, ease of deployment, variable power
usage/transmission range profile for nodes, as well as allows
the entire network to enter a deep-sleep mode to conserve
power. In addition, all the nodes fulfil the same functions,
which enables the network to reroute a signal should one node
be damaged (e.g. destruction due to heavy machinery collision).
Initial experiments show transmission range between the nodes
in excess of 1000 ft. in clear space. Initial experiments show
also that the range can be further extended by placing the nodes
in the proximity of a conductor.
The data from all the nodes are collected from a central node,
which is always awake and therefore always “listening” for
transmit-request messages from every other node in the
network. After having received a packet of data, the central
node exchanges information with a laptop through a serial port.
The process of collecting data from the serial port and then
elaborate them in order to make them useful for the user is
performed by means of a Python script running on the main
computer.
IV. EXPERIMENTAL RESULTS
An apparatus consisting of a 1.5 m high 15.24-cm-diameter
section of stove pipe is placed inside a portable glovebox with
controlled the humidity. To prepare a dust layer using this
apparatus an accurately weighted quantity of dust is placed in
the dust reservoir and dispersed upward by means of
compressed air. A petri dish is placed on the sensor platform at
the base of the stove pipe to catch the settling dust. The petri
dish is weighed before and after deposition of the dust for
calculation of the surface loading density. The dust deposition
setup is capable of dispersing both coal and rock dust over the
humidity range from 10% ‐ 90% RH. Pittsburg Pulverized Coal
(PPC) with the mean particle diameter of 61.3µm (S.D.
43.8µm) is used to test the optical dust deposition sensor.
Fig. 6 shows experimental results from the optical reflectance
of accumulated stacks of coal dust at different humidity levels.
The results show good agreement with the Beer-Lambert law
for deposited particles and strong dependence on the humidity
level.
2mm
Figure 4: A macro image of the microfabricated mass sensor. Wire‐bonds
are visible, connecting the sensor electrically to the PCB substrate. Note
that the sensor is elevated on pedestals to allow for the deflection of the
paddle due to mass loading.
Figure 5: Output capacitance vs. dust mass for MEMS flow sensor with
SOI thickness of 70um, beam width of 50 um, capacitor finger gap of 10
um. Output capacitance changes about 0.14 pF for 10-mg dust.
6 mm
4. V. CONCLUSION
In this paper, we present a low-cost/low-power wirelessly
enabled distributed sensing system that can be located
throughout the mine to continuously monitor TIC of the dust
that is being deposited throughout the mine. The sensors use
continuous optical, gravimetric, and dielectrometry methods to
measure the TIC of the deposited stack of float dust/rock dust
as well as the moisture content and the mass of the deposited
stack. Low power design have been develop to enable the
sensors to operate for extended periods underground without
the need for changing their batteries. The sensors have been
designed to periodically refresh their surface as well as mitigate
the dust accumulation in the optical path. Experimental results
from testing the sensor prototypes in a realistic test bed
subjected to the deposition of the coal dust/rock dust mixture at
different humidity levels are presented.
ACKNOWLEDGMENT
The authors would like to thank University of Illinois at
Chicago Nanotechnology Core Facility (NCF) and University
of California at Berkeley’s Marvell Nanofabrication
Laboratory for providing necessary equipment to continue the
research. We also thank Son Duy Nguyen for help with the
designs of the mass sensor. This project is supported by a grant
from the Center for Disease Control and Prevention (CDC)/
National Institute of Occupational Safety and Health (NIOSH),
contract# 200-2013-57155.
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[2] M. Sapko, J. Pinkerton and J. Bubash, 'Optical dust deposition
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508-513, 1988.
[3] M. Sapko and H. Verakis. 'Technical development of the coal dust
explosibility meter.' SME 2006 Annual Meeting, St. Louis, MO. 2006.
[4] S. Nguyen, I. Paprotny, P. Wright and R. White, 'MEMS capacitive flow
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no. 5, pp. 808-845, 2004.
[6] " XBee/XBee-PRO® DigiMesh 2.4 RF Modules," Digi International
Inc.2015.
Figure 6: Experimental results showing normalized reflection from coal
dust on a white substrate obtained using a functionalized optical sensing
element prototype. Blue and green dots are experimental results from
PPC coal dust under high (RH %85±5) and low (RH %30±5) humidity
condition inside the coal deposition chamber, respectively. Red and blue
lines are exponential fit to the recorded data.