This paper reports on progress made in the development of backscatter absorption gas imaging (BAGI) instrumentation suitable for hydrocarbon leak detection. While prototypes of the gas imager have been demonstrated to detect natural gas leaks in the past,...
National Technical Information Service (NTIS)
... Descriptors : *MONITORING, *SPACE SHUTTLES, *ROCKET EXHAUST, *GAS ... INFRARED IMAGES, RADIATION ABSORPTION, ABSORBERS ...
DTIC Science & Technology
A video imaging system for detecting hazardous gas leaks. Visual displays of invisible gas clouds are produced by radiation augmentation of the field of view of an imaging device by radiation corresponding to an absorption line of the gas to be detected. The field of view ...
Energy Citations Database
DOEpatents
Backscatter absorption gas imaging (BAGI) is a technique that uses infrared active imaging to generate real-time video imagery of gas plumes. We describe a method that employs imaging at two wavelengths (absorbed and not absorbed by the gas to be ...
PubMed
A system is described that is suitable for use in determining the location of leaks of gases having a background concentration. The system is a point-wise backscatter absorption gas measurement system that measures absorption and distance to each point of an image. The absorption measurement ...
Mar 5, 2004 ... In the image, methane gas is uniformly mixed with hydrogen, the main gas in ... Dark locales are places of strong methane absorption, ...
NASA Website
This paper presents a new laser-based method of gas detection that permits real-time television images of gases to be produced. The principle of this technique [which is called backscatter absorption gas imaging (BAGI)] and the operation of two instruments used to implement it are described. ...
Backscatter absorption gas imaging (BAGI) is a laser gas-sensing technique that allows the real-time video imaging of gas plumes. It is essentially a hybrid between lidar and laser radar (ladar); in that it uses a laser active-imager to produce ...
The feasibility of applying gas filter correlation techniques and infrared imaging technology to the problem of quantifying gaseous HCl produced in the exhaust of the Space Transportation System (STS) is explored. Modeling of HCl absorption and emission f...
... SO2 by laser-induced fluorescence and construction of a hand-held imager for stand-off detection of CH4 using backscatter absorption gas imaging. ...
This paper reports the use of hematin Langmuir-Blodgett (LB) films to detect carbon monoxide gas at the room temperature, based on changes in the optical absorption of the films. Hematin LB films were deposited on quartz and glass substrates. For the film deposited on quartz substrate, an increase in the absorption spectra of the film ...
NASA Astrophysics Data System (ADS)
We demonstrate a scheme for direct absorption imaging of an ultracold ground-state polar molecular gas near quantum degeneracy. Imaging molecules without closed optical cycling transitions is challenging. Our technique relies on photon-shot-noise-limited absorption imaging ...
The location of gases that are not visible to the unaided human eye can be determined using tuned light sources that spectroscopically probe the gases and cameras that can provide images corresponding to the absorption of the gases. The present invention is a light source for a backscatter absorption gas ...
The Backscatter Absorption Gas Imaging (BAGI) technique allows the real-time visualization of visibly undetectable gas clouds. A BAGI instrument has been built that consists of a laser active-imager and allows gas imaging to be performed on at least 60 ...
... Title : Gas-Solid Absorption Characteristics of Supramolecular Compounds Using a Hermetically Controlled Atmosphere Automated Absorption ...
The design and evaluation of a backscatter-absorption gas-imaging sensor that operates in a pulsed mode is described. It is capable of video visualization of natural gas leaks. Its development was motivated by the need for a methane imaging system to operate at ranges and sensitivities useful to the natural ...
A new concept for the detection and tracking of toxic or flammable gases resulting from accidental spills or leaks is presented. The Backscatter/Absorption Gas Imaging (BAGI) technique is based on the optical radiation augmentation of the field of view of an imaging device by laser radiation corresponding to an ...
Aug 1, 1996 ... The blue-green color results from the absorption of red light by methane gas in Uranus' deep, cold and remarkably clear atmosphere. ...
A new concept for the detection and tracking of toxic or flammable gases resulting from accidental spills or leaks is presented. The Backscatter Absorption Gas Imaging (BAGI) technique is based on the optical radiation augmentation of the field of view of...
A new concept for the detection and tracking of toxic or flammable gases resulting from accidental spills or leaks is presented. The BAGI technique (backscatter/absorption gas imaging) integrates a laser and a flying-spot imager, and allows the normally invisible gases to be visualized on a standard TV monitor. ...
... AIAA-2003-3259 Acoustic Absorption Measurements for ... AIAA 2003 - 3259 Acoustic Absorption Measurements for Characterization of Gas Mixing ...
The backscatter absorption gas imaging (BAGI) technique is a laser remote sensing method that fuses the chemical detection attributes of chemical lidar with the visualization capability of imaging laser radar (ladar) to allow real-time television images of invisible gas ...
A method and apparatus is described for compensating for reflection losses in an optical path length modulated absorption-absorption gas analyzer used for determining the density of a reference gas in an unknown gas sample. The apparatus comprises a first...
... cylinder of aluminum which was machined to give a ... The classical absorption was subtracted ... in the section on specific heats, The characteristic ...
A theoretical and experimental investigation is presented of inverse Bremsstrahlung absorption of CW
NASA Technical Reports Server (NTRS)
... Title : CHOICE OF AN APPROPRIATE MEAN ABSORPTION COEFFICIENT FOR USE IN THE GENERAL GREY GAS EQUATIONS. ...
A hyperspectral consists of a great number of spectral images. Although these spectral images are obtained simultaneously, due to a number of optical effects the hyperspectral bands are not co-registered. This has been found to be particularly prominent in images of regions near the absorption bands of atmospheric ...
... Abstract : An appartatus and process for removing contaminants in a gas through absorption in a liquid absorbent is provided wherein the ...
An absorption filter for the purification of gas or air streams, especially gas or air streams which contain toxic or radioactive contaminants is described.
A new concept for the detection and tracking of toxic or flammable gases resulting from accidental spills or leaks is presented. The Backscatter Absorption Gas Imaging (BAGI) technique is based on the optical radiation augmentation of the field of view of an imaging device by laser radiation corresponding to an ...
Uncooled thermal cameras using microbolometer focal plane arrays may be used in the long wave infrared (LWIR) for the optical detection of hydrocarbon gas leaks. The strong absorption of hydrocarbon gases in the LWIR may be used to advantage along with the LWIR optical transmission window of the atmosphere. Improvements in the detection algorithm and more ...
A drop impacting a solid surface with sufficient velocity will emit many small droplets creating a splash. However, splashing is completely suppressed if the surrounding gas pressure is lowered. The mechanism by which the gas affects splashing remains unknown. We use high-speed interference imaging to measure the air beneath all ...
E-print Network
For the past six years the Liquefied Gaseous Fuels (LGF) Spill Effects Program at the Lawrence Livermore National Laboratory (LLNL) has been studying the possible hazards associated with large-scale spills of hazardous materials. This effort has focused primarily on modeling and measurement of the dispersion of large, heavier-than-air gas clouds. A need was discovered for the ...
The transmission properties of gas phase samples heavily contaminated with aerosols, particles, and water vapor generated by combustible materials as well as the feasibility of pollution detection were obtained by terahertz time domain spectroscopy (THz-TDS) in the 0.2 to 3 THz frequency region. The absorption properties of solid-state samples and their ...
The interstellar medium comprises a mixture of molecular, atomic, and ionized gas of various temperatures, with each phase traced by independent data such as mm-wave CO lines, radio 21-cm emission and absorption lines, ultraviolet absorption lines, and optical emission lines. Each phase contains dust, so the total amount of ...
This research focuses on understanding the formation and evolution of galaxies via their extended gaseous halos using the methods of quasar absorption line systems. Galaxy-absorber pairs provide direct observational constraints on competing scenarios aimed at establishing the role of gas in galaxy formation and evolution. Our sample consists of 40 ...
A multiconfiguration aperture synthesis mapping of the Perseus arm H I absorption line toward Cas A has been performed using the VLA. The sensitivity achieved was sufficient to detect optical depths as low as 0.03 and as large as about 5 over a region about 5 arcmin in diameter. Optical depth images are presented as gray scale with contours superposed for ...
The radicals formed in the flash photolysis of 2-methylbut-1-ene and subsequent reactions have been investigated by kinetic spectroscopy and gas liquid chromatography. Less than 10% of photo products are formed by a molecular made of fission of the excited olefin, and of the radical modes the relative probabilities of band fission, beta(CH):beta(CH):alpha(CC) are 13:1.37:1. ...
The company performs continuous absorption of fluorine - containing waste gas. This low-waste technology is a continuous method for absorption of SiF4 from waste gas of the phosphate-fertilizer industry. It works upon the principle of turbogrid absorption...
Gas-fluid levels in the colon observed in radiographs are abnormal and usually indicate serious gastrointestinal disease. Colonic gas-fluid levels associated with concurrent abdominal pain and malabsorption of lactose, documented by lactose breath hydrogen testing, were observed in five children. Incomplete lactose absorption is a ...
PubMed Central
Modern laser-spectroscopic techniques usually incorporate one or more laser beams and depend on their radiative interaction with some spectroscopic feature of the gas. Attention is given to laser absorption, laser-induced fluorescence, Rayleigh scattering, and Raman scattering. Consideration is given to UV Rayleigh scattering applied to aerodynamic flows ...
A photionization detector is described with a high quantum efficiency at wavelengths shorter than about 2000 A. This instrument, coupled to a xenon gas scintillation proportional counter has an energy resolution of 9.5% FWHM at 6 keV. The vapor pressure and absorption coefficient of TMAE are measured and the prospects of an imaging ...
The detection of gas leaks represents a critical operation performed regularly by the gas industry to maintain the integrity and safety of its vast network of piping, both above and below the ground. We are developing a technology that allows the real-time imaging of gas plumes in a television format. Termed ...
DOE Information Bridge
To access the risks and chances of deposition of submicron particles in the gas-exchange area of the lung, a precise three-dimensional (3D)-localization of the sites of deposition is essential--especially because local peaks of deposition are expected in the acinar tree and in individual alveoli. In this study we developed the workflow for such an investigation. We ...
... Title : GAS CHROMATOGRAPHIC ESTIMATION OF CARBON MONOXIDE PRODUCED DURING OXYGEN ABSORPTION BY ALKALINE ...
... Title : EXPERIMENTAL VERIFICATION OF THEORETICAL RELATIONS BETWEEN TOTAL GAS ABSORPTIVITIES AND TOTAL GAS EMISSIVIES ...
This report describes the results of a series of tests to investigate the feasibility of detecting oil films on water with an infrared (IR) laser active imaging system. The imager that was used in this effort was developed for the US Navy by the Lawrence Livermore National Laboratory (LLNL) as part of the backscatter absorption ...
... of a nearby metal nanosphere. Descriptors : *METALS, *IMAGES, *NANOSTRUCTURES ... ABSORPTION, PLASMONS, DETECTORS, MAGNETIC ...
Imaging spectrometry has the potential of remotely detecting atmospheric trace gases on the basis of their absorption of radiation. Ozone absorbs particulary in the ultraviolet and visible range of the spectrum, whereas water vapor has strong absorption features in the near infrared. Hence, spectrometry is expected to be a promising ...
A fundamental astrophysical question is the role of gas in galaxy evolution. Mg II absorption as observed in quasar spectra is found to arise in a broad range of gaseous galactic environments. But the overall relationship between the distribution of Mg II absorbers, their host galaxies, and the larger scale galactic structure is not well known. Lyman-alpha ...
The first gated LIF-imaging and absorption spectroscopy has been performed on laser desorbed plumes from organic crystals which are commonly used as MALDI (Matrix Assisted Laser Desorption Ionization) matrices. These plasma diagnostic techniques, including ion probe measurements were employed to investigate the desorbed products, densities, fractional ...
We present findings for DG Tau B and VV CrA, two of the objects observed in our Spitzer Infrared Spectrograph (IRS) project to search for molecular absorption in edge-on disks, along with near-IR spectroscopy of the CO fundamental transitions and mid-IR imaging. While the only gas absorption seen in the Spitzer IRS ...
A real time method of measuring and recording the efficacy of vapor containment in and around critical hazard fume hoods is being developed. An infrared camera whose response is restricted to a spectral range that overlaps a strong absorption band in a non-toxic gas is used to render real-time video images of the presence and flow of ...
Active, safe real-time method of measuring and recording the efficacy of vapor containment in and around critical hazard fume hoods has been developed. An infrared camera whose response is restricted to a spectral range that overlaps a strong absorption band in a nontoxic gas is used to render real-time video images of the presence and ...
The objective of this thesis was to experimentally demonstrate the viability of utilizing CCD video cameras to measure, detect and monitor molecular air pollution and trace contaminants in the atmosphere. Differential spectral absorption wavelengths were used to identify and delineate specific pollutants. Standard video output carried data to appropriate ...
... ABSORPTION SPECTRA, ABSORPTION, OVERLAP, DYE ... FLOW, DOPPLER EFFECT, GAS FLOW ... PATHS, HIGH TEMPERATURE, VOLUME ...
... Accession Number : ADP000282. Title : Resonance Absorption Measurements of Atom Concentrations in Reacting Gas Mixtures. ...
The infrared emission bands (also known as the UIR bands.) have recently been observed in absorption
The optical absorption lines of quasars are examined, and implications of the lines for the physical
We produce YbF molecules with a density of 1018 m-3 using laser ablation inside a cryogenically cooled cell filled with a helium buffer gas. Using absorption imaging and absorption spectroscopy we study the formation, diffusion, thermalization, and optical pumping of the molecules. The ...
We present broadband HST / WFPC2 images, ground-based H? images, and VLA H I 21 cm emission maps of the nearby galaxy ESO 1327-2041, which is located 38? west of the quasar PKS 1327-206. We find H I 21 cm absorption in the quasar spectrum at czabs = 5250 and 5500 km s-1, the same velocities that metal lines of Na I and Ca II were ...
Researchers seek improved ways to measure the surface absorption and the bulk absorption coefficients of highly transparent materials. Procedures are presented here by which one may determine separately the surface absorption and the bulk absorption coeff...
We analyze the absorption and emission-line profiles produced by a set of simple, cool gas wind models motivated by galactic-scale outflow observations. We implement Monte Carlo radiative transfer techniques that track the propagation of scattered and fluorescent photons to generate one-dimensional spectra and two-dimensional spectral ...
beam transmittance algorithms include the effects of Rayleigh scattering (TR), ozone absorption (TO), uniformly mixed gas absorption (TUM), water vapor absorption (TW), aerosol...
National Renewable Energy Laboratory (NREL)
While hyperspectral imaging systems are increasingly used in remote sensing and offer enhanced scene characterization relative to univariate and multispectral technologies, it has proven difficult in practice to extract all of the useful information from these systems due to overwhelming data volume, confounding atmospheric effects, and the limited a priori knowledge regarding ...
... Accession Number : ADA174010. Title : X-Ray Absorption Spectroscopy of Gas Phase Metal Clusters. Descriptive Note : Technical rept.,. ...
The efficiency of benzene removal from coke-oven gas in absorption units OAO Alchevskkoks with new packing is assessed.
... Title : KINETIC COOLING OF A GAS BY ABSORPTION OF CO SUB 2 LASER RADIATION-APPLIED PHYSICS LETTERS, V20, NO3, P129-132. ...
Investigation on the Hydrogen Gas Sensor Based on Exothermicity Reaction by Hydrogen Absorption into the Pd Film
... Accession Number : AD0729204. Title : Investigation of Laser Resonant Absorption for Gas Dynamics Measurements. Descriptive Note : Final rept. ...
... Title : Cyclic Absorption/Desorption of Gas in a Liquid Wall Film,. Corporate Author : TRW INC REDONDO BEACH CALIF. ...
The paper presents a detailed theoretical analysis of the process of gas absorption to a thin liquid
May 21, 2009 ... An analytic model for calculating absorption spectra from gas which is in coronal equilibrium is available. This model is the coronal analog ...
... Accession Number : AD0267508. Title : A GAS ABSORPTION CELL IN THE SOFT X RAY REGION. Corporate Author : CORNELL UNIV ITHACA NY. ...
Sep 9, 2009 ... You are here: GES DISC Home Ozone Documentation Publications sensor SCIAMACHY (Scanning Imaging Absorption Spectrometer for ...
This report is the result of a Backscatter Absorption Gas Imaging (BAGI) development task in which the feasibility of imaging five gaseous species was to be evaluated. The five gases to be evaluated are carbon monoxide, carbon dioxide, hydrogen, hydrogen sulfide, and Halon. Because it is clear that some of these ...
We have used Galaxy IMage 2D (GIM2D) to quantify the morphological properties of 40 intermediate-redshift Mg II absorption-selected galaxies [0.03 ? Wr(2796) ? 2.9 �], imaged with WFPC-2/Hubble Space Telescope (HST), and compared them to the halo gas properties measured from HIRES/Keck and UVES/VLT quasar ...
An appartatus and process for removing contaminants in a gas through absorption in a liquid absorbent is provided wherein the apparatus comprises a first tube having a gas inlet for receiving a contaminant enriched gas and an outlet, and a second tube for...
The Backscatter/Absorption Gas Imaging (BAGI) technique is a promising new concept for the location and tracking of hazardous gases. The fundamental principle of the technique is that if hazardous gases were visible to the human eye, it would be easy to locate the source of a leak or, in the case of an accidental spill, to determine ...
Photoacoustic (PA) spectroscopy and detection involving condensed samples and gas phase signal generation are briefly reviewed. Theoretical considerations, instrumentation, and applications are discussed with emphasis on electronic materials studies. Applications include PA absorption spectroscopy of single crystal CdS and ion implanted GaAs int he bandgap ...
... deformation. In the case of VT14 and TS5 alloys the role of the thickness of the gas-impregnated layer is more substantial. ...
... boosters. Descriptors : *HYDROGEN CHLORIDE, SPACE SHUTTLES, *GAS ANALYSIS, *COMBUSTION PRODUCTS, ABSORPTION, BOOSTER ...
... and direct readout of the ... GAS ANALYSIS, *DISPLAY SYSTEMS, *READ OUT TECHNIQUES ... SAMPLING, CONTAMINANTS, OPTICAL DETECTORS ...
a differential scanning calorimeter, gas chromatography, gas chromatography/mass spectrograph, atomic absorption spectrophotometer, inductively coupled ...
... absorption. It was found that the creep deformation was highly affected by the solubility controlled gas, carbon dioxide. ...
... The property of gas bubbles to cause absorption of ultrasonic energy propagating in the medium water gas bubbles was established as a means ...
... INTERACTION), *HELIUM, GAS FLOW, FLOATING BODIES, HEAT, ABSORPTION, LIMITATIONS, FLOW RATE, GASES, MICROWAVES ...
Techniques for the gas-phase absorption of laser energy with ultimate conversion to heat or directed
... Accession Number : ADA068769. Title : Combustion Gas Measurements Using Tunable Laser Absorption Spectroscopy. ...
We present high resolution (R = 114,000) ultraviolet measurements of the interstellar absorption line profiles of the C IV (1550 �) high ionization doublet recorded toward the nearby B2Ve star HD 158427 (d ~ 74 pc). These data, which were recorded with the recently re-furbished Space Telescope Imaging Spectrograph instrument on the Hubble Space ...
Infrared photodetectors with spectrally selective response are highly desirable for applications such as hyper-spectral imaging and gas sensing. Owing to the ability of photonic density of states modification and dispersion engineering, photonic crystals appear to be one of the most promising platforms for infrared photodetectors with spectrally-selective ...
... When the imaging wavelength is matched to the absorption of hemoglobin and myoglobin the resulting image would reflect the state of oxygenation ...
... in the course of the absorption of microwaves. Modulating the microwave input power thermal waves ... was successfully applied to image the depth ...
Tunable diode laser absorption spectroscopy (TDLAS) shows promise for in situ monitoring in high-speed flows. However, the dynamic nature of typical flows of supersonic combustors, gas turbine engines and augmenters can also lead to inhomogenities that cannot be captured by a single line-of-sight TDLAS measurement. Instead, multiple measurements varied ...
We show that x-rays from a recently demonstrated table top source of bright, ultrafast, coherent synchrotron radiation [Kneip et al., Nat. Phys. 6, 980 (2010)] can be applied to phase contrast imaging of biological specimens. Our scheme is based on focusing a high power short pulse laser in a tenuous gas jet, setting up a plasma wakefield accelerator that ...
Gas absorption often limits the use of metals by causing changes in bulk mechanical and electrical properties. However, while metals are often exposed to dissociated gases, no data appear to be available on absorption kinetics in atomic environments. This...
...Metals in Refuse-Derived Fuel by Atomic Absorption Spectroscopy,1 IBR approved for...Measurement in Natural Gas by Atomic Absorption Spectroscopy, approved December 1...Measurement in Natural Gas by Atomic Absorption Spectroscopy, approved December...
Code of Federal Regulations, 2011
...equipment shall be provided with an absorption-type filter capable of removing...the isooctane solution through a gas-absorption train consisting of the following components...independent of the input pressure. 2. An absorption apparatus consisting of an inlet...
New low-temperature methane absorption coefficients pertinent to the Titan environment are presented as derived from the Huygens DISR spectral measurements combined with the in-situ measurements of the methane gas abundance profile measured by the Huygens Gas Chromatograph/Mass Spectrometer (GCMS). The visible and near-infrared ...
