National Library of Energy BETA

Sample records for absorption lidar dial

  1. ARM - Campaign Instrument - lidar-dial

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    govInstrumentslidar-dial Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign Instrument : Dial Lidar (LIDAR-DIAL) Instrument Categories Aerosols, Atmospheric Profiling Campaigns ARM-FIRE Water Vapor Experiment [ Download Data ] Southern Great Plains, 2000.11.01 - 2000.12.31 Water Vapor IOP [ Download Data ] Southern Great Plains, 2000.09.18 - 2000.10.08 Primary Measurements Taken The following measurements are those considered scientifically

  2. Development and Deployment of a Compact Eye-Safe Scanning Differential absorption Lidar (DIAL) for Spatial Mapping of Carbon Dioxide for Monitoring/Verification/Accounting at Geologic Sequestration Sites

    SciTech Connect (OSTI)

    Repasky, Kevin

    2014-03-31

    A scanning differential absorption lidar (DIAL) instrument for monitoring carbon dioxide has been developed. The laser transmitter uses two tunable discrete mode laser diodes (DMLD) operating in the continuous wave (cw) mode with one locked to the online absorption wavelength and the other operating at the offline wavelength. Two in-line fiber optic switches are used to switch between online and offline operation. After the fiber optic switch, an acousto- optic modulator (AOM) is used to generate a pulse train used to injection seed an erbium doped fiber amplifier (EDFA) to produce eye-safe laser pulses with maximum pulse energies of 66 {micro}J, a pulse repetition frequency of 15 kHz, and an operating wavelength of 1.571 {micro}m. The DIAL receiver uses a 28 cm diameter Schmidt-Cassegrain telescope to collect that backscattered light, which is then monitored using a photo-multiplier tube (PMT) module operating in the photon counting mode. The DIAL instrument has been operated from a laboratory environment on the campus of Montana State University, at the Zero Emission Research Technology (ZERT) field site located in the agricultural research area on the western end of the Montana State University campus, and at the Big Sky Carbon Sequestration Partnership site located in north-central Montana. DIAL data has been collected and profiles have been validated using a co-located Licor LI-820 Gas Analyzer point sensor.

  3. Differential absorption lidar measurements of atmospheric temperature profiles - Theory and experiment

    SciTech Connect (OSTI)

    Theopold, F.A.; Boesenberg, J. )

    1993-04-01

    The method of measuring atmospheric temperature profiles with differential absorption lidar (DIAL), based on the temperature dependence of oxygen absorption lines in the near-IR, is investigated in detail. Particularly, the influence of Doppler broadening on the Rayleigh-backscattered signal is evaluated, and a correction method for this effect is presented which requires an accurate estimate of the molecular and particle backscatter contributions; this is noted not to be achievable by the usual lidar inversion techniques. Under realistic conditions, resulting errors may be as high as 10 K. First range-resolved measurements using this technique are presented, using a slightly modified DIAL system originally constructed for water vapor measurements. While much better resolution can certainly be achieved by technical improvements, the errors introduced by the uncertainty of the backscatter contributions will remain and determine the accuracy that can be obtained with this method. 35 refs.

  4. Lidar techniques for chemical and aerosol air pollution studies

    SciTech Connect (OSTI)

    Hardesty, R.M.

    1993-12-31

    At the Wave Propagation Laboratory (WPL), lidar methods are being applied in several areas of air pollution research. Differential absorption lidar (DIAL) systems for measuring ozone, ethylene, and other pollutants have been recently developed. The ozone instrument profiles ozone concentration in the boundary layer and lower troposphere to study sources, sinks, and transport of ozone. A goal is to combine DIAL and Doppler lidar techniques for measurement of the vertical fluxes of ozone and other pollutants. Doppler lidars have been also used at WPL to study visibility reduction caused by aerosol pollutants at the Grand Canyon, and to investigate dispersion of hazardous emissions near the Rocky Flats nuclear plant.

  5. IR DIAL performance modeling

    SciTech Connect (OSTI)

    Sharlemann, E.T.

    1994-07-01

    We are developing a DIAL performance model for CALIOPE at LLNL. The intent of the model is to provide quick and interactive parameter sensitivity calculations with immediate graphical output. A brief overview of the features of the performance model is given, along with an example of performance calculations for a non-CALIOPE application.

  6. Analysis and design methodology for the development of optimized, direct-detection CO{sub 2} DIAL receivers

    SciTech Connect (OSTI)

    Cooke, B.J.; Laubscher, B.E.; Cafferty, M.

    1996-12-31

    The analysis methodology and corresponding analytical tools for the design of optimized, low-noise, hard target return CO{sub 2} Differential Absorption Lidar (DIAL) receiver systems implementing both single element detectors and multi-pixel imaging arrays for passive/active, remote-sensing applications are presented. System parameters and components composing the receiver include: aperture, focal length, field of view, cold shield requirements, image plane dimensions, pixel dimensions, pixel pitch and fill factor, detection quantum efficiency, optical filter requirements, amplifier and temporal sampling parameters. The performance analysis is accomplished by calculating the system`s CO{sub 2} laser range response, total noise, optical geometric form factor and optical resolution. The noise components include speckle, photon noise due to signal, scene and atmospheric background, cold shield, and electronic noise. System resolution is simulated through cascaded optical transfer functions and includes effects due to atmosphere, optics, image sampling, and system motion. Experimental results of a developmental single-element detector receiver designed to detect 100 ns wide laser pulses (10 - 100 kHz pulse repetition rates) backscattered from hard-targets at nominal ranges of 10 km are presented. The receiver sensitivity is near-background noise limited, given an 8.5-11.5 {mu}m radiant optical bandwidth, with the total noise floor spectrally white for maximum pulse averaging efficiency.

  7. Lidar for remote sensing; Proceedings of the Meeting, Berlin, Germany, June 24-26, 1992

    SciTech Connect (OSTI)

    Becherer, R.J.; Werner, C.

    1992-01-01

    The present volume on lidar for remote sensing discusses lidar system techniques for remote sensing of atmospheric pollution, airborne and surface-based lidar for environmental sensing of water and oceans, Doppler lidar for wind sensing and related measurement, aerosol measurements using lidar, ozone, water vapor, temperature, and density sensing with lidar systems, and new lidar technology systems and concepts. Attention is given to remote sensing of air pollution over large European cities by lidar, differential absorption lidar monitoring of atmospheric atomic mercury, an experimental evaluation of an airborne depth-sounding lidar, and remote sensing of the sea by tunable multichannel lidar. Topics addressed include recent developments in lidar techniques to measure the wind in the middle atmosphere, recent stratospheric aerosol measurements with a combined Raman elastic-backscatter lidar, the development of an eye-safe IR aerosol lidar, and temperature measurement by rotational Raman lidar.

  8. Austin Energy Dials Down Home Energy Use With Smart Phones |...

    Energy Savers [EERE]

    Phones Austin Energy Dials Down Home Energy Use With Smart Phones bbrnstoriesaustinenergy9-2-14.jpg Better Buildings Residential Network member Austin Energy used summer's...

  9. ARM - Measurement - Lidar polarization

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    govMeasurementsLidar polarization ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Lidar polarization The temporal and geometric behavior of the electric field vector of an electromagnetic wave transmitted or received by a lidar system, e.g. elliptical polarization, differential reflectivity, phase shift, co-polar correlation coefficient, linear depolarization ratio. Categories Cloud Properties

  10. emerging-lidar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Emerging LIDAR Based Approaches For 3D Mapping Presentation at Argonne TRACC May 11, 2012 2:00 PM(CDT) TRACC Conference Room: Building 222, Room D-233 Dr. Xin Chen Senior Research Scientist at Nokia Chicago, IL Abstract Modeling real world in the 3D modality is broadly applicable to the surveying, navigation, intelligent vehicle, urban modeling, mapping and augmented reality fields. With the rapid development of LIDAR sensors and global positioning technologies, large scale, geo-referenced and

  11. Austin Energy Dials Down Home Energy Use With Smart Phones | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy Austin Energy Dials Down Home Energy Use With Smart Phones Austin Energy Dials Down Home Energy Use With Smart Phones bbrn_stories_austin_energy_9-2-14.jpg Better Buildings Residential Network member Austin Energy used summer's unpredictable weather patterns as an opportunity to remind Austin, Texas, residents of its Power PartnerSM Thermostat incentive. Customers can receive an $85 rebate for one of several "smart" thermostats that they can control remotely from a smart

  12. Water vapor and ozone profiles with a CO{sub 2} DIAL system in south Italy

    SciTech Connect (OSTI)

    Bellecci, C.; Caputi, G.; De Donato, F.; Gaudio, P.; Valentini, M.

    1996-12-31

    In this paper the authors present the work carried out at the University of Calabria regarding a prototype of a DIAL system. This has been realized for remote pollution monitoring. Most of the efforts have been done to perform several measurements on an horizontal path in order to scan the wide surrounding area. The concentrations of ozone and water vapor have been carried out using two different methods both related with the DIAL technique. With the integrated technique, average concentrations have been evaluated up to 5 km using topographical targets. In the range resolution technique, profiles of ozone and water vapor have been performed up to 700 m with a spatial resolution of about 30 m. Although the system needs a revision in several subsystems of its set-up, the experimentation has pointed out the performance available and the necessary improvements.

  13. Dialing in the Properties of Dual Metallic-Insulating Materials | Argonne

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    National Laboratory Dialing in the Properties of Dual Metallic-Insulating Materials February 11, 2016 Tweet EmailPrint Materials that undergo metal-insulator transitions (MITs) are under intense study, because the transition is scientifically fascinating and technologically promising for various applications. Among these materials, VO2 has served as a prototype due to its favorable transition temperature. While the physical underpinnings of the transition have been heavily investigated

  14. CX-010481: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Differential Absorption Lidar (DIAL) for Spatial Mapping of Carbon Dioxide CX(s) Applied: A1, A9, A11, B3.6 Date: 05/29/2013 Location(s): Montana Offices(s): National Energy Technology Laboratory

  15. Raman Lidar (RL) Handbook

    SciTech Connect (OSTI)

    Newsom, RK

    2009-03-01

    The Raman lidar at the ARM Climate Research Facility (ACRF) Southern Great Plains (SGP) Central Facility (SGPRL) is an active, ground-based laser remote sensing instrument that measures height and time resolved profiles of water vapor mixing ratio and several cloud- and aerosol-related quantities. The system is a non-commercial custom-built instrument developed by Sandia National Laboratories specifically for the ARM Program. It is fully computer automated, and will run unattended for many days following a brief (~5-minute) startup period. The self-contained system (requiring only external electrical power) is housed in a climate-controlled 8x8x20 standard shipping container.

  16. New 'knobs' can dial in control of materials > EMC2 News > The Energy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Materials Center at Cornell EMC2 News Latest News Room-temperature lithium metal battery closer to reality › First self-assembled superconductor structure created › McGovern incubator embraces Embark and Ecolectro › In This Section EMC2 News Archived News Stories New 'knobs' can dial in control of materials February 24th, 2015 › By Anne Ju Brendan Faeth An artist's rendering of strontium iridate, an oxide whose properties can be controlled by applying spin-orbit interactions or

  17. Doppler Lidar (DL) Handbook

    SciTech Connect (OSTI)

    Newsom, RK

    2012-02-13

    The Doppler lidar (DL) is an active remote sensing instrument that provides range- and time-resolved measurements of radial velocity and attenuated backscatter. The principle of operation is similar to radar in that pulses of energy are transmitted into the atmosphere; the energy scattered back to the transceiver is collected and measured as a time-resolved signal. From the time delay between each outgoing transmitted pulse and the backscattered signal, the distance to the scatterer is inferred. The radial or line-of-sight velocity of the scatterers is determined from the Doppler frequency shift of the backscattered radiation. The DL uses a heterodyne detection technique in which the return signal is mixed with a reference laser beam (i.e., local oscillator) of known frequency. An onboard signal processing computer then determines the Doppler frequency shift from the spectra of the heterodyne signal. The energy content of the Doppler spectra can also be used to determine attenuated backscatter.

  18. Sandia Energy - ARM Raman Lidar Development

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Raman lidar was delivered in the fall of 1995. The automated nature of the Raman lidar Raman scattering boxr1 provided multiple-day views of water vapor mixing ratio and...

  19. Finnish Meteorological Institute Doppler Lidar

    SciTech Connect (OSTI)

    Ewan OConnor

    2015-03-27

    This doppler lidar system provides co-polar and cross polar attenuated backscatter coefficients,signal strength, and doppler velocities in the cloud and in the boundary level, including uncertainties for all parameters. Using the doppler beam swinging DBS technique, and Vertical Azimuthal Display (VAD) this system also provides vertical profiles of horizontal winds.

  20. ARM - Campaign Instrument - co2lidar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    lidar Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign Instrument : Carbon Dioxide Doppler Lidar (CO2LIDAR) Instrument Categories Cloud Properties Campaigns Remote Cloud Sensing (RCS) Field Evaluation [ Download Data ] Southern Great Plains, 1994.04.01 - 1994.05.31 Primary Measurements Taken The following measurements are those considered scientifically relevant. Refer to the datastream (netcdf) file headers for the list of all available

  1. Sandia Energy - ARM Raman Lidar Applications

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    in the analysis deriving water vapor flux observations using coincident Raman and Doppler lidar measurements and characterizing entrainment in cumulus clouds using Raman...

  2. Application of coherent 10 micron imaging lidar

    SciTech Connect (OSTI)

    Simpson, M.L.; Hutchinson, D.P.; Richards, R.K.; Bennett, C.A.

    1997-04-01

    With the continuing progress in mid-IR array detector technology and high bandwidth fan-outs, i.f. electronics, high speed digitizers, and processing capability, true coherent imaging lidar is becoming a reality. In this paper experimental results are described using a 10 micron coherent imaging lidar.

  3. Application of lidar to current atmospheric topics

    SciTech Connect (OSTI)

    Sedlacek, A.J. III

    1996-12-31

    The goal of the conference was to address the various applications of lidar to topics of interest in the atmospheric community. Specifically, with the development of frequency-agile, all solid state laser systems, high-quantum-efficiency detectors, increased computational power along with new and more powerful algorithms, and novel detection schemes, the application of lidar to both old and new problems has expanded. This expansion is evidenced by the contributions to the proceedings, which demonstrate the progress made on a variety of atmospheric remote sensing problems, both theoretically and experimentally. The first session focused on aerosol, ozone, and temperature profile measurements from ground-based units. The second session, Chemical Detection, provided applications of lidar to the detection of atmospheric pollutants. Papers in the third session, Wind and Turbulence Measurements, described the Multi-center Airborne Coherent Atmospheric Wind Sensor (MACAWS) experiments, Doppler techniques for ground-based wind profiling and mesopause radial wind and temperature measurements utilizing a frequency-agile lidar system. The papers in the last two sessions, Recent Advanced in Lidar Technology and Techniques and Advanced Operational Lidars, provided insights into novel approaches, materials, and techniques that would be of value to the lidar community. Papers have been processed separately for inclusion on the data base.

  4. Micropulse Lidar The ARM Program studies

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    1 Micropulse Lidar The ARM Program studies clouds, sunlight, and their interactions to understand how they affect Earth's climate. One of the many instruments used to look at clouds at the SGP CART site is the micropulse lidar (MPL; "lidar" was coined from "light distance and ranging"). The ARM Program operates five MPLs. One is at the SGP central facility; one is at the North Slope of Alaska CART site in Barrow, Alaska; and three are for use at the Tropical Western Pacific

  5. ARM - Field Campaign - Aerosol Lidar Validation Experiment -...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    govCampaignsAerosol Lidar Validation Experiment - ALIVE Campaign Links ALIVE Website ARM Data Discovery Browse Data Comments? We would love to hear from you Send us a note below...

  6. ARM - Publications: Science Team Meeting Documents

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Water Vapor Profiling During WVIOP#3 and AFWEX2000 Using Ground-Based Differential Absorption Lidar Boesenberg, J. (a), Linne, H. (a), Jansen, F. (a), Ertel, K. (a), Lammert, A. (a), and Wilkerson, T. (b), Max-Planck-Institut fuer Meteorologie, Hamburg (a), Utah State Univerity (b) Eleventh Atmospheric Radiation Measurement (ARM) Science Team Meeting The differential absorption lidar (DIAL) system of the MPI participated in both the WVIOP#3 and AFWEX2000 experiments. It was operated on 11 days

  7. Raman lidar/AERI PBL Height Product

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Ferrare, Richard

    2012-12-14

    Planetary Boundary Layer (PBL) heights have been computed using potential temperature profiles derived from Raman lidar and AERI measurements. Raman lidar measurements of the rotational Raman scattering from nitrogen and oxygen are used to derive vertical profiles of potential temperature. AERI measurements of downwelling radiance are used in a physical retrieval approach (Smith et al. 1999, Feltz et al. 1998) to derive profiles of temperature and water vapor. The Raman lidar and AERI potential temperature profiles are merged to create a single potential temperature profile for computing PBL heights. PBL heights were derived from these merged potential temperature profiles using a modified Heffter (1980) technique that was tailored to the SGP site (Della Monache et al., 2004). PBL heights were computed on an hourly basis for the period January 1, 2009 through December 31, 2011. These heights are provided as meters above ground level.

  8. Raman lidar/AERI PBL Height Product

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Ferrare, Richard

    Planetary Boundary Layer (PBL) heights have been computed using potential temperature profiles derived from Raman lidar and AERI measurements. Raman lidar measurements of the rotational Raman scattering from nitrogen and oxygen are used to derive vertical profiles of potential temperature. AERI measurements of downwelling radiance are used in a physical retrieval approach (Smith et al. 1999, Feltz et al. 1998) to derive profiles of temperature and water vapor. The Raman lidar and AERI potential temperature profiles are merged to create a single potential temperature profile for computing PBL heights. PBL heights were derived from these merged potential temperature profiles using a modified Heffter (1980) technique that was tailored to the SGP site (Della Monache et al., 2004). PBL heights were computed on an hourly basis for the period January 1, 2009 through December 31, 2011. These heights are provided as meters above ground level.

  9. Lidar Inter-Comparison Exercise Final Campaign Report

    SciTech Connect (OSTI)

    Protat, A; Young, S

    2015-02-01

    The objective of this field campaign was to evaluate the performance of the new Leosphere R-MAN 510 lidar, procured by the Australian Bureau of Meteorology, by testing it against the MicroPulse Lidar (MPL) and Raman lidars, at the Darwin Atmospheric Radiation Measurement (ARM) site. This lidar is an eye-safe (355 nm), turn-key mini Raman lidar, which allows for the detection of aerosols and cloud properties, and the retrieval of particulate extinction profiles. To accomplish this evaluation, the R-MAN 510 lidar has been operated at the Darwin ARM site, next to the MPL, Raman lidar, and Vaisala ceilometer (VCEIL) for three months (from 20 January 2013 to 20 April 2013) in order to collect a sufficient sample size for statistical comparisons.

  10. ARM - PI Product - Finnish Meteorological Institute Doppler Lidar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ProductsFinnish Meteorological Institute Doppler Lidar Citation DOI: 10.5439/1177194 [ What is this? ] ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Finnish Meteorological Institute Doppler Lidar [ research data - External funding ] This doppler lidar system provides co-polar and cross polar attenuated backscatter coefficients,signal strength, and doppler velocities in the cloud and in the boundary

  11. Accessing the Energy Department's Lidar Buoy Data off Virginia Beach |

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Department of Energy Accessing the Energy Department's Lidar Buoy Data off Virginia Beach Accessing the Energy Department's Lidar Buoy Data off Virginia Beach In December 2014, Pacific Northwest National Laboratory (PNNL) deployed the Energy Department's floating lidar buoy off of Virginia Beach, Virginia, in less than 30 meters (m) of water, approximately 28 nautical miles offshore (approximate coordinates: 36° 52.00' N, 75° 29.53' W). This buoy is collecting meteorological and

  12. LiDAR (Lewicki & Oldenburg, 2005) | Open Energy Information

    Open Energy Info (EERE)

    Technique LiDAR Activity Date Usefulness useful DOE-funding Unknown References Jennifer L. Lewicki, Curtis M. Oldenburg (2005) Strategies To Detect Hidden Geothermal Systems...

  13. LiDAR (Lewicki & Oldenburg, 2004) | Open Energy Information

    Open Energy Info (EERE)

    Technique LiDAR Activity Date Usefulness useful DOE-funding Unknown References Jennifer L. Lewicki, Curtis M. Oldenburg (2004) Strategies For Detecting Hidden Geothermal Systems...

  14. ARM - Field Campaign - M-PACE - Polarization Diversity Lidar (PDL)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    - Polarization Diversity Lidar (PDL) Campaign Links M-PACE Website ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : M-PACE - Polarization Diversity Lidar (PDL) 2004.09.01 - 2004.10.21 Lead Scientist : Kenneth Sassen For data sets, see below. Abstract In support of M-PACE, a Polarization Diversity Lidar (PDL), was deployed to the NSA. Unlike the micro pulses of the MPL (micropulse lidar) present at NSA, the

  15. ARM - PI Product - Raman lidar/AERI PBL Height Product

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ProductsRaman lidar/AERI PBL Height Product ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send PI Product : Raman lidar/AERI PBL Height Product Planetary Boundary Layer (PBL) heights have been computed using potential temperature profiles derived from Raman lidar and AERI measurements. Raman lidar measurements of the rotational Raman scattering from nitrogen and oxygen are used to derive vertical profiles of potential

  16. Advanced Lidars for ARM: What Would We Get?

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    of downtime due to laser issues - Data (raw and processed) available from lidar.ssec.wisc.edu - Products are cloud optical depth, extinction, backscatter, and depolarization...

  17. ARM - Field Campaign - Lidar support for ICECAPS at Summit, Greenland

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    govCampaignsLidar support for ICECAPS at Summit, Greenland Campaign Links ICECAPS Campaign Summary (PDF) Summit Station Research Highlight New Data from Greenland for Arctic...

  18. A Lidar View of Clouds in Southeastern China

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Lidar View of Clouds in Southeastern China For original submission and image(s), see ARM Research Highlights http:www.arm.govsciencehighlights Research Highlight From May 2008...

  19. Three-dimensional elastic lidar winds

    SciTech Connect (OSTI)

    Buttler, W.T.

    1996-07-01

    Maximum cross-correlation techniques have been used with satellite data to estimate winds and sea surface velocities for several years. Los Alamos National Laboratory (LANL) is currently using a variation of the basic maximum cross-correlation technique, coupled with a deterministic application of a vector median filter, to measure transverse winds as a function of range and altitude from incoherent elastic backscatter lidar data taken throughout large volumes within the atmospheric boundary layer. Hourly representations of three- dimensional wind fields, derived from elastic lidar data taken during an air-quality study performed in a region of complex terrain near Sunland Park, New Mexico, are presented and compared with results from an Environmental Protection Agency (EPA) approved laser doppler velocimeter. The wind fields showed persistent large scale eddies as well as general terrain following winds in the Rio Grande valley.

  20. Doppler Lidar Wind Value-Added Product

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    8 Doppler Lidar Wind Value-Added Product RK Newsom C Sivaraman TR Shippert LD Riihimaki July 2015 DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would

  1. Lidar techniques for search and rescue

    SciTech Connect (OSTI)

    Cabral, W.L.

    1985-01-01

    Four techniques for using LIDAR in Search and Rescue Operations will be discussed. The topic will include laser retroreflection, laser-induced fluorescence in the visible, laser-induced fluorescence during daylight hours, and laser-induced fluorescence in the uv. These techniques use high-repetition rate lasers at a variety of frequencies to induce either fluorescence in dye markers or retroreflection from plastic corner cubes on life preservers and other emergency markers.

  2. CX-006557: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Differential Absorption Lidar (DIAL) for Spatial Mapping of Carbon DioxideCX(s) Applied: B3.8, B3.11Date: 08/17/2011Location(s): Toole County, MontanaOffice(s): Fossil Energy, National Energy Technology Laboratory

  3. Adaptive Data Processing Technique for Lidar-Assisted Control to Bridge the Gap between Lidar Systems and Wind Turbines: Preprint

    SciTech Connect (OSTI)

    Schlipf, David; Raach, Steffen; Haizmann, Florian; Cheng, Po Wen; Fleming, Paul; Scholbrock, Andrew, Krishnamurthy, Raghu; Boquet, Mathieu

    2015-12-14

    This paper presents first steps toward an adaptive lidar data processing technique crucial for lidar-assisted control in wind turbines. The prediction time and the quality of the wind preview from lidar measurements depend on several factors and are not constant. If the data processing is not continually adjusted, the benefit of lidar-assisted control cannot be fully exploited, or can even result in harmful control action. An online analysis of the lidar and turbine data are necessary to continually reassess the prediction time and lidar data quality. In this work, a structured process to develop an analysis tool for the prediction time and a new hardware setup for lidar-assisted control are presented. The tool consists of an online estimation of the rotor effective wind speed from lidar and turbine data and the implementation of an online cross correlation to determine the time shift between both signals. Further, initial results from an ongoing campaign in which this system was employed for providing lidar preview for feed-forward pitch control are presented.

  4. ARM - Measurement - Aerosol absorption

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    absorption ARM Data Discovery Browse Data Comments? We would love to hear from you Send us a note below or call us at 1-888-ARM-DATA. Send Measurement : Aerosol absorption The...

  5. Application of coherent lidar to ion measurements in plasma diagnostics

    SciTech Connect (OSTI)

    Hutchinson, D.P.; Richards, R.K.; Bennett, C.A.; Simpson, M.L.

    1997-03-01

    A coherent lidar system has been constructed for the measurement of alpha particles in a burning plasma. The lidar system consists of a pulsed CO{sub 2} laser transmitter and a heterodyne receiver. The receiver local oscillator is a cw, sequence-band CO{sub 2} laser operating with a 63.23 GHz offset from the transmitter.

  6. Validation of Innovative Exploration Technologies for Newberry Volcano: LIDAR of Newberry Volcano 2012

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Jaffe, Todd

    2012-01-01

    Validation of Innovative Exploration Technologies for Newberry Volcano: LIDAR of Newberry Volcano 2012

  7. ARM: 10-second Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    2004-10-01

    10-second Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  8. ARM: 2-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    2004-10-01

    2-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  9. ARM: 10-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    1998-03-01

    10-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  10. ARM: 1-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    2004-10-01

    1-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  11. ARM: 1-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    2004-10-01

    1-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  12. ARM: 10-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Newsom, Rob; Goldsmith, John

    1998-03-01

    10-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  13. Validation of Innovative Exploration Technologies for Newberry Volcano: LIDAR of Newberry Volcano 2012

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Jaffe, Todd

    Validation of Innovative Exploration Technologies for Newberry Volcano: LIDAR of Newberry Volcano 2012

  14. ARM: 10-second Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    10-second Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  15. ARM: 10-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    10-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  16. ARM: 10-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    10-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  17. ARM: 2-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sivaraman, Chitra; Flynn, Connor

    2-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  18. ARM: 1-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    1-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  19. ARM: 1-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    1-minute Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  20. Residential Absorption Water Heater

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Residential Absorption Water Heater 2014 Building Technologies Office Peer Review Kyle ... Target MarketAudience: Residential gas water heating Key Partners: GE CRADA partner SRA ...

  1. Atmospheric Data, Images, and Animations from Lidar Instruments used by the University of Wisconsin Lidar Group

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    The Space Science and Engineering Center is a research and development center affiliated with the University of Wisconsin-Madison’s Graduate School. Its primary focus is on geophysical research and technology to enhance understanding of the atmosphere of Earth, the other planets in the Solar System, and the cosmos. SSEC develops new observing tools for spacecraft, aircraft, and ground-based platforms, and models atmospheric phenomena. The Center receives, manages and distributes huge amounts of geophysical data and develops software to visualize and manipulate these data for use by researchers and operational meteorologists all over the world.[Taken from About SSEC at http://www.ssec.wisc.edu/overview/] A huge collection of data products, images, and animations comes to the SSEC from the University of Wisconsin Lidar Group. Contents of this collection include: • An archive of thousands of Lidar images acquired before 2004 • Arctic HSRL, MMCR, PAERI, MWR, Radiosonde, and CRAS forecast data Data after May 1, 2004 • MPEG animations and Lidar Multiple Scattering Models

  2. Atmospheric Data, Images, and Animations from Lidar Instruments used by the University of Wisconsin Lidar Group

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    The Space Science and Engineering Center is a research and development center affiliated with the University of Wisconsin-Madisons Graduate School. Its primary focus is on geophysical research and technology to enhance understanding of the atmosphere of Earth, the other planets in the Solar System, and the cosmos. SSEC develops new observing tools for spacecraft, aircraft, and ground-based platforms, and models atmospheric phenomena. The Center receives, manages and distributes huge amounts of geophysical data and develops software to visualize and manipulate these data for use by researchers and operational meteorologists all over the world.[Taken from About SSEC at http://www.ssec.wisc.edu/overview/] A huge collection of data products, images, and animations comes to the SSEC from the University of Wisconsin Lidar Group. Contents of this collection include: An archive of thousands of Lidar images acquired before 2004 Arctic HSRL, MMCR, PAERI, MWR, Radiosonde, and CRAS forecast data Data after May 1, 2004 MPEG animations and Lidar Multiple Scattering Models

  3. LiDAR (Lewicki & Oldenburg) | Open Energy Information

    Open Energy Info (EERE)

    Technique LiDAR Activity Date Usefulness useful DOE-funding Unknown References Jennifer L. Lewicki, Curtis M. Oldenburg (Unknown) Near-Surface Co2 Monitoring And Analysis To...

  4. Cloud properties derived from the High Spectral Resolution Lidar...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    depth. These results will be compared to similar results observed during the first 8-months of our current deployment at Eureka, Canada (80N, 86.2W). http:lidar.ssec.wisc.edu...

  5. ARM - Field Campaign - NASA Coordinated Airborne CO2 Lidar Flight...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    govCampaignsNASA Coordinated Airborne CO2 Lidar Flight Test Campaign ARM Data Discovery Browse Data Comments? We would love to hear from you Send us a note below or call us at...

  6. Solar absorption surface panel

    DOE Patents [OSTI]

    Santala, Teuvo J.

    1978-01-01

    A composite metal of aluminum and nickel is used to form an economical solar absorption surface for a collector plate wherein an intermetallic compound of the aluminum and nickel provides a surface morphology with high absorptance and relatively low infrared emittance along with good durability.

  7. Absorption Heat Pump Basics

    Broader source: Energy.gov [DOE]

    Absorption heat pumps are essentially air-source heat pumps driven not by electricity, but by a heat source such as natural gas, propane, solar-heated water, or geothermal-heated water. Because natural gas is the most common heat source for absorption heat pumps, they are also referred to as gas-fired heat pumps.

  8. Lidar Inter-Comparison Exercise Final Campaign Report

    SciTech Connect (OSTI)

    Protat, Alain; Young, S.

    2015-02-01

    The objective of this IOP was to evaluate the performances of the new Leosphere R-MAN 510 lidar procured by the Australian Bureau of Meteorology, by testing it against the MPL and Raman lidars at the Darwin ARM site. This lidar is an eye-safe (355 nm), turn-key mini Raman lidar, which allows for the detection of aerosols and cloud properties, and the retrieval of particulate extinction profiles. To do so, the R-MAN 510 lidar has been operated at the Darwin ARM site, next to the MPL, Raman lidar, and Vaisala ceilometer for three months (from 20 January 2013 to 20 April 2013) in order to collect a good sample for statistical comparisons. The comparisons with the Raman lidar were not performed, since the Raman lidar attenuated backscatter and depolarization ratio product was not available. A new product has just been delivered to the ARM archive as a value-added product, hence this study will continue. Nevertheless we have developed software to match the different space and time resolutions of the other lidars and project the data onto a common grid to permit detailed comparison of the instruments’ performance and an enhanced analysis of clouds and aerosols through the use of composite data products, like the ratios of attenuated backscatters, attenuated scattering ratios and depolarization ratios. Comparisons between the MPL and R-MAN510 lidar data exhibit large differences in total attenuated backscatter at 355 and 532 nm, attenuated scattering ratios, and aerosol volume depolarization ratios. Differences in attenuated backscatter result mainly from the different relative contributions of scattering from molecules and particles at the different wavelengths, but there are some intriguing differences that will require further investigations. The differences in volume depolarization ratios are due to the much larger contribution of molecular returns to the volume depolarization ratio (5 times larger at 355 nm than at 532 nm). The R-MAN510 lidar is also found to be much less sensitive to daylight solar background illumination, which is greater at the visible wavelength than in the UV.

  9. Femtosecond Coherent Anti-Stokes Raman Spectroscopy (CARS) As Next Generation Nonlinear LIDAR Spectroscopy and Microscopy

    SciTech Connect (OSTI)

    Ooi, C. H. Raymond

    2009-07-10

    Nonlinear spectroscopy using coherent anti-Stokes Raman scattering and femtosecond laser pulses has been successfully developed as powerful tools for chemical analysis and biological imaging. Recent developments show promising possibilities of incorporating CARS into LIDAR system for remote detection of molecular species in airborne particles. The corresponding theory is being developed to describe nonlinear scattering of a mesoscopic particle composed of complex molecules by laser pulses with arbitrary shape and spectral content. Microscopic many-body transform theory is used to compute the third order susceptibility for CARS in molecules with known absorption spectrum and vibrational modes. The theory is combined with an integral scattering formula and Mie-Lorentz formulae, giving a rigorous formalism which provides powerful numerical experimentation of CARS spectra, particularly on the variations with the laser parameters and the direction of detection.

  10. Evaluation of three lidar scanning strategies for turbulence measurements

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Newman, J. F.; Klein, P. M.; Wharton, S.; Sathe, A.; Bonin, T. A.; Chilson, P. B.; Muschinski, A.

    2015-11-24

    Several errors occur when a traditional Doppler-beam swinging (DBS) or velocityazimuth display (VAD) strategy is used to measure turbulence with a lidar. To mitigate some of these errors, a scanning strategy was recently developed which employs six beam positions to independently estimate the u, v, and w velocity variances and covariances. In order to assess the ability of these different scanning techniques to measure turbulence, a Halo scanning lidar, WindCube v2 pulsed lidar and ZephIR continuous wave lidar were deployed at field sites in Oklahoma and Colorado with collocated sonic anemometers. Results indicate that the six-beam strategy mitigates somemoreof the errors caused by VAD and DBS scans, but the strategy is strongly affected by errors in the variance measured at the different beam positions. The ZephIR and WindCube lidars overestimated horizontal variance values by over 60 % under unstable conditions as a result of variance contamination, where additional variance components contaminate the true value of the variance. A correction method was developed for the WindCube lidar that uses variance calculated from the vertical beam position to reduce variance contamination in the u and v variance components. The correction method reduced WindCube variance estimates by over 20 % at both the Oklahoma and Colorado sites under unstable conditions, when variance contamination is largest. This correction method can be easily applied to other lidars that contain a vertical beam position and is a promising method for accurately estimating turbulence with commercially available lidars.less

  11. Elastic Scattering LIDAR Data Acquisition Visualization and Analysis

    Energy Science and Technology Software Center (OSTI)

    1999-10-12

    ELASTIC/EVIEW is a software system that controls an elastic scattering atmospheric Light Detection and Ranging (LIDAR) instrument. It can acquire elastic scattering LIDAR data using this system and produce images of one, two, and three-dimensional atmospheric data on particulates and other atmospheric pollutants. The user interface is a modern menu driven syatem with appropriate support for user configuration and printing files.

  12. LIDAR Wind Speed Measurements of Evolving Wind Fields

    SciTech Connect (OSTI)

    Simley, E.; Pao, L. Y.

    2012-07-01

    Light Detection and Ranging (LIDAR) systems are able to measure the speed of incoming wind before it interacts with a wind turbine rotor. These preview wind measurements can be used in feedforward control systems designed to reduce turbine loads. However, the degree to which such preview-based control techniques can reduce loads by reacting to turbulence depends on how accurately the incoming wind field can be measured. Past studies have assumed Taylor's frozen turbulence hypothesis, which implies that turbulence remains unchanged as it advects downwind at the mean wind speed. With Taylor's hypothesis applied, the only source of wind speed measurement error is distortion caused by the LIDAR. This study introduces wind evolution, characterized by the longitudinal coherence of the wind, to LIDAR measurement simulations to create a more realistic measurement model. A simple model of wind evolution is applied to a frozen wind field used in previous studies to investigate the effects of varying the intensity of wind evolution. LIDAR measurements are also evaluated with a large eddy simulation of a stable boundary layer provided by the National Center for Atmospheric Research. Simulation results show the combined effects of LIDAR errors and wind evolution for realistic turbine-mounted LIDAR measurement scenarios.

  13. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, Gershon (Oak Ridge, TN)

    1984-01-01

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  14. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, G.

    1982-06-16

    The efficiency of an absorption heat pump system is improved by conducting liquid from a second stage evaporator thereof to an auxiliary heat exchanger positioned downstream of a primary heat exchanger in the desorber of the system.

  15. Solar selective absorption coatings

    DOE Patents [OSTI]

    Mahoney, Alan R. (Albuquerque, NM); Reed, Scott T. (Albuquerque, NM); Ashley, Carol S. (Albuquerque, NM); Martinez, F. Edward (Horseheads, NY)

    2003-10-14

    A new class of solar selective absorption coatings are disclosed. These coatings comprise a structured metallic overlayer such that the overlayer has a sub-micron structure designed to efficiently absorb solar radiation, while retaining low thermal emissivity for infrared thermal radiation. A sol-gel layer protects the structured metallic overlayer from mechanical, thermal, and environmental degradation. Processes for producing such solar selective absorption coatings are also disclosed.

  16. Solar selective absorption coatings

    DOE Patents [OSTI]

    Mahoney, Alan R. (Albuquerque, NM); Reed, Scott T. (Albuquerque, NM); Ashley, Carol S. (Albuquerque, NM); Martinez, F. Edward (Horseheads, NY)

    2004-08-31

    A new class of solar selective absorption coatings are disclosed. These coatings comprise a structured metallic overlayer such that the overlayer has a sub-micron structure designed to efficiently absorb solar radiation, while retaining low thermal emissivity for infrared thermal radiation. A sol-gel layer protects the structured metallic overlayer from mechanical, thermal, and environmental degradation. Processes for producing such solar selective absorption coatings are also disclosed.

  17. Optical absorption measurement system

    DOE Patents [OSTI]

    Draggoo, Vaughn G. (Livermore, CA); Morton, Richard G. (San Diego, CA); Sawicki, Richard H. (Pleasanton, CA); Bissinger, Horst D. (Livermore, CA)

    1989-01-01

    The system of the present invention contemplates a non-intrusive method for measuring the temperature rise of optical elements under high laser power optical loading to determine the absorption coefficient. The method comprises irradiating the optical element with a high average power laser beam, viewing the optical element with an infrared camera to determine the temperature across the optical element and calculating the absorption of the optical element from the temperature.

  18. LiDAR At Chocolate Mountains Area (Alm, Et Al., 2010) | Open...

    Open Energy Info (EERE)

    aerial Li-DAR survey flown over the project areas, securing over 177,000 square kilometers of <30cm accuracy digital elevation data. LiDAR data were analyzed to characterize...

  19. Seven-effect absorption refrigeration

    DOE Patents [OSTI]

    DeVault, Robert C. (Knoxville, TN); Biermann, Wendell J. (Fayetteville, NY)

    1989-01-01

    A seven-effect absorption refrigeration cycle is disclosed utilizing three absorption circuits. In addition, a heat exchanger is used for heating the generator of the low absorption circuit with heat rejected from the condenser and absorber of the medium absorption circuit. A heat exchanger is also provided for heating the generator of the medium absorption circuit with heat rejected from the condenser and absorber of the high absorption circuit. If desired, another heat exchanger can also be provided for heating the evaporator of the high absorption circuit with rejected heat from either the condenser or absorber of the low absorption circuit.

  20. Seven-effect absorption refrigeration

    DOE Patents [OSTI]

    DeVault, R.C.; Biermann, W.J.

    1989-05-09

    A seven-effect absorption refrigeration cycle is disclosed utilizing three absorption circuits. In addition, a heat exchanger is used for heating the generator of the low absorption circuit with heat rejected from the condenser and absorber of the medium absorption circuit. A heat exchanger is also provided for heating the generator of the medium absorption circuit with heat rejected from the condenser and absorber of the high absorption circuit. If desired, another heat exchanger can also be provided for heating the evaporator of the high absorption circuit with rejected heat from either the condenser or absorber of the low absorption circuit. 1 fig.

  1. Comparison of Two Independent LIDAR-Based Pitch Control Designs

    SciTech Connect (OSTI)

    Dunne, F.; Schlipf, D.; Pao, L. Y.

    2012-08-01

    Two different lidar-based feedforward controllers have previously been designed for the NREL 5 MW wind turbine model under separate studies. Feedforward controller A uses a finite-impulse-response design, with 5 seconds of preview, and three rotating lidar measurements. Feedforward controller B uses a static-gain design, with the preview time defined by the pitch actuator dynamics, a simulation of a real nacelle-based scanning lidar system, and a lowpass filter defined by the lidar configuration. These controllers are now directly compared under the same lidar configuration, in terms of fatigue load reduction, rotor speed regulation, and power capture. The various differences in design choices are discussed and compared. We also compare frequency plots of individual pitch feedforward and collective pitch feedforward load reductions, and we see that individual pitch feedforward is effective mainly at the once-per-revolution and twice-per-revolution frequencies. We also explain how to determine the required preview time by breaking it down into separate parts, and we then compare it to the expected preview time available.

  2. A Doppler lidar for measuring winds in the middle atmosphere

    SciTech Connect (OSTI)

    Chanin, M.L.; Garnier, A.; Hauchecorne, A.; Porteneuve, J. )

    1989-11-01

    The possibility of measuring winds in the middle atmosphere with a Doppler lidar has just been demonstrated. It is aimed at studying the wave-mean flow interaction, when used is association with the Rayleigh lidar providing density and temperature profiles and their fluctuations. The new Doppler lidar relies on the Rayleigh scattering from air molecules is designed to cover the height range 25-60 km, a region where radars cannot operate. The Doppler shift to the backscattered echo is measured by inter-comparing the signal detected through each of the two high-resolution, narrow band-pass Fabry-Perot interferometers tuned on either side of the emitted laser line.

  3. Coplanar Doppler Lidar Retrieval of Rotors from T-REX

    SciTech Connect (OSTI)

    Hill, Michael; Calhoun, Ron; Fernando, H. J. S.; Wieser, Andreas; Dornbrack, Andreas; Weissmann, Martin; Mayr, G.; Newsom, Rob K.

    2010-03-01

    Two coherent Doppler lidars were deployed during the Terrain-induced Rotor EXperiment (T-REX). Coplanar Range Height Indicator (RHI) scans by the lidars (along the same azimuthal angle) allowed retrieval of two-dimensional velocity vectors on a vertical/cross-barrier plane using the least squares method. Vortices are shown to evolve and advect in the flow field, allowing analysis of their behavior in the mountain-wave-boundary layer system. The locations, magnitudes, and evolution of the vortices can be studied through calculated fields of velocity, vorticity, streamlines, and swirl. Two classes of vortical motions are identified: rotors and sub-rotors, which differ in scale and behavior. The level of coordination of the two lidars and the nature of the output (i.e., in range-gates) creates inherent restrictions on the spatial and temporal resolution of retrieved fields.

  4. Doppler lidar for measurement of atmospheric wind fields

    SciTech Connect (OSTI)

    Menzies, R.T. )

    1991-01-01

    Measurements of wind fields in the earth's troposphere with daily global coverage is widely considered as a significant advance for forecasting and transport studies. For optimal use by NWP (Numerical Weather Prediction) models the horizontal and vertical resolutions should be approximately 100 km and 1 km, respectively. For boundary layer studies vertical resolution of a few hundred meters seems essential. Earth-orbiting Doppler lidar has a unique capability to measure global winds in the troposphere with the high vertical resolution required. The lidar approach depends on transmission of pulses with high spectral purity and backscattering from the atmospheric aerosol particles or layered clouds to provide a return signal. Recent field measurement campaigns using NASA research aircraft have resulted in collection of aerosol and cloud data which can be used to optimize the Doppler lidar instrument design and measurement strategy. 5 refs.

  5. ARM: 10-minute TEMPORARY Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sivaraman, Chitra; Flynn, Connor

    2010-12-15

    10-minute TEMPORARY Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  6. ARM: 10-minute TEMPORARY Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sivaraman, Chitra; Flynn, Connor

    2010-12-15

    10-minute TEMPORARY Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  7. ARM: ARSCL: cloud boundaries from first Clothiaux algorithms on Vaisala or Belfort ceilometers, Micropulse lidar, and MMCR

    SciTech Connect (OSTI)

    Karen Johnson; Michael Jensen

    1996-11-08

    ARSCL: cloud boundaries from first Clothiaux algorithms on Vaisala or Belfort ceilometers, Micropulse lidar, and MMCR

  8. ARM: ARSCL: multiple outputs from first Clothiaux algorithms on Vaisala or Belfort ceilometers, Micropulse lidar, and MMCR

    SciTech Connect (OSTI)

    Karen Johnson; Michael Jensen

    1996-11-08

    ARSCL: multiple outputs from first Clothiaux algorithms on Vaisala or Belfort ceilometers, Micropulse lidar, and MMCR

  9. ARM: 10-minute TEMPORARY Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sivaraman, Chitra; Flynn, Connor

    10-minute TEMPORARY Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm

  10. ARM: 10-minute TEMPORARY Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Sivaraman, Chitra; Flynn, Connor

    10-minute TEMPORARY Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm

  11. ARM: ARSCL: multiple outputs from first Clothiaux algorithms on Vaisala or Belfort ceilometers, Micropulse lidar, and MMCR

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Karen Johnson; Michael Jensen

    ARSCL: multiple outputs from first Clothiaux algorithms on Vaisala or Belfort ceilometers, Micropulse lidar, and MMCR

  12. ARM: ARSCL: cloud boundaries from first Clothiaux algorithms on Vaisala or Belfort ceilometers, Micropulse lidar, and MMCR

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Karen Johnson; Michael Jensen

    ARSCL: cloud boundaries from first Clothiaux algorithms on Vaisala or Belfort ceilometers, Micropulse lidar, and MMCR

  13. Absorption heat pump system

    DOE Patents [OSTI]

    Grossman, Gershon (Oak Ridge, TN); Perez-Blanco, Horacio (Knoxville, TN)

    1984-01-01

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  14. ARM - Field Campaign - M-PACE HSR Lidar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    HSR Lidar Campaign Links Full Proposal Abstract M-PACE Website ARM Data Discovery Browse Data Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : M-PACE HSR Lidar 2004.09.27 - 2004.10.21 Lead Scientist : Edwin Eloranta For data sets, see below. Abstract The HSRL provided calibrated vertical profiles of optical depth, backscatter cross section and depoloarization at a wavelength of 532 nm. Profiles were acquired at 2.5 second intervals with

  15. Imaging doppler lidar for wind turbine wake profiling

    DOE Patents [OSTI]

    Bossert, David J.

    2015-11-19

    An imaging Doppler lidar (IDL) enables the measurement of the velocity distribution of a large volume, in parallel, and at high spatial resolution in the wake of a wind turbine. Because the IDL is non-scanning, it can be orders of magnitude faster than conventional coherent lidar approaches. Scattering can be obtained from naturally occurring aerosol particles. Furthermore, the wind velocity can be measured directly from Doppler shifts of the laser light, so the measurement can be accomplished at large standoff and at wide fields-of-view.

  16. Assessment and Optimization of Lidar Measurement Availability for Wind Turbine Control: Preprint

    SciTech Connect (OSTI)

    Davoust, S.; Jehu, A.; Bouillet, M.; Bardon, M.; Vercherin, B.; Scholbrock, A.; Fleming, P.; Wright, A.

    2014-05-01

    Turbine-mounted lidars provide preview measurements of the incoming wind field. By reducing loads on critical components and increasing the potential power extracted from the wind, the performance of wind turbine controllers can be improved [2]. As a result, integrating a light detection and ranging (lidar) system has the potential to lower the cost of wind energy. This paper presents an evaluation of turbine-mounted lidar availability. Availability is a metric which measures the proportion of time the lidar is producing controller-usable data, and is essential when a wind turbine controller relies on a lidar. To accomplish this, researchers from Avent Lidar Technology and the National Renewable Energy Laboratory first assessed and modeled the effect of extreme atmospheric events. This shows how a multirange lidar delivers measurements for a wide variety of conditions. Second, by using a theoretical approach and conducting an analysis of field feedback, we investigated the effects of the lidar setup on the wind turbine. This helps determine the optimal lidar mounting position at the back of the nacelle, and establishes a relationship between availability, turbine rpm, and lidar sampling time. Lastly, we considered the role of the wind field reconstruction strategies and the turbine controller on the definition and performance of a lidar's measurement availability.

  17. Aerosol backscatter measurements at 10. 6 micrometers with airborne and ground-based CO sub 2 Doppler lidars over the Colorado high plains. 1. Lidar intercomparison

    SciTech Connect (OSTI)

    Bowdle, D.A. ); Rothermel, J. ); Vaughan, J.M.; Brown, D.W. ); Post, M.J. )

    1991-03-20

    An airborne continuous wave (CW) focused CO{sub 2} Doppler lidar and a ground-based pulsed CO{sub 2} Doppler lidar were used to obtain seven pairs of comparative measurements of tropospheric aerosol backscatter profiles at 10.6 {mu}m wavelength, near Denver, Colorado, during a 20-day period in July 1982. In regions of uniform backscatter the two lidars show good agreement, with differences usually less than {approximately}50% near 8-km altitude and less than a factor of 2 or 3 elsewhere but with the pulsed lidar often lower than the CW lidar. Near sharp backscatter gradients the two lidars show poorer agreement, with the pulsed lidar usually higher than the CW lidar. Most discrepancies arise from a combination of atmospheric factors and instrument factors, particularly small-scale areal and temporal backscatter heterogeneity above the planetary boundary layer, unusual large-scale vertical backscatter structure in the upper troposphere and lower stratosphere, and differences in the spatial resolution, detection threshold, and noise estimation for the two lidars.

  18. NASA Lidar system support and MOPA technology demonstration. Final report

    SciTech Connect (OSTI)

    Laughman, L.M.; Capuano, B.; Wayne, R.J.

    1986-08-01

    A series of lidar design and technology demonstration tasks in support of a CO/sub 2/ lidar program is discussed. The first of these tasks is discussed in Section VI of this report under the heading of NASA Optical Lidar Design and it consists of detailed recommendations for the layout of a CO/sub 2/ Doppler lidar incorporating then existing NASA optical components and mounts. The second phase of this work consisted of the design, development, and delivery to NASA of a novel acousto-optic laser frequency stabilization system for use with the existing NASA ring laser transmitter. The second major task in this program encompasses the design and experimental demonstration of a master oscillator-power amplifier (MOPA) laser transmitter utilizing a commercially available laser as the amplifier. The MOPA design including the low chirp master oscillator is discussed in detail. Experimental results are given for one, two and three pass amplification. The report includes operating procedures for the MOPA system.

  19. Raman Lidar Profiles–Temperature (RLPROFTEMP) Value-Added Product

    SciTech Connect (OSTI)

    Newsom, RK; Sivaraman, C; McFarlane, SA

    2012-10-31

    The purpose of this document is to describe the Raman Lidar Profiles–Temperature (RLPROFTEMP) value-added product (VAP) and the procedures used to derive atmospheric temperature profiles from the raw RL measurements. Sections 2 and 4 describe the input and output variables, respectively. Section 3 discusses the theory behind the measurement and the details of the algorithm, including calibration and overlap correction.

  20. Enhanced Gas Absorption

    Office of Scientific and Technical Information (OSTI)

    Enhanced Gas Absorption in the Ionic Liquid 1-n-Hexyl-3-methylimidazolium Bis(Trifluoromethylsulfonyl)amide ([hmim][Tf 2 N]) Confined in Silica Slit Pores: A Molecular Simulation Study Wei Shi, ∗,†,‡,¶ and David R. Luebke † U. S. Department of Energy, National Energy Technology Laboratory, Pittsburgh, PA 15236, USA, URS Corporation, South Park, PA 15129, USA, and Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, PA 15261, USA E-mail:

  1. Long-Path Absorption

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Path Absorption - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Fuel Cycle Defense Waste Management Programs Advanced Nuclear

  2. LIDAR Thomson scattering for advanced tokamaks. Final report

    SciTech Connect (OSTI)

    Molvik, A.W.; Lerche, R.A.; Nilson, D.G.

    1996-03-18

    The LIDAR Thomson Scattering for Advanced Tokamaks project made a valuable contribution by combining LLNL expertise from the MFE Program: tokamak design and diagnostics, and the ICF Program and Physics Dept.: short-pulse lasers and fast streak cameras. This multidisciplinary group evaluated issues involved in achieving a factor of 20 higher high spatial resolution (to as small as 2-3 mm) from the present state of the art in LIDAR Thomson scattering, and developed conceptual designs to apply LIDAR Thomson scattering to three tokamaks: Upgraded divertor measurements in the existing DIII-D tokamak; Both core and divertor LIDAR Thomson scattering in the proposed (now cancelled) TPX; and core, edge, and divertor LIDAR Thomson scattering on the presently planned International Tokamak Experimental Reactor, ITER. Other issues were evaluated in addition to the time response required for a few millimeter spatial resolution. These include the optimum wavelength, 100 Hz operation of the laser and detectors, minimizing stray light - always the Achilles heel of Thomson scattering, and time dispersion in optics that could prevent good spatial resolution. Innovative features of our work included: custom short pulsed laser concepts to meet specific requirements, use of a prism spectrometer to maintain a constant optical path length for high temporal and spatial resolution, the concept of a laser focus outside the plasma to ionize gas and form an external fiducial to use in locating the plasma edge as well as to spread the laser energy over a large enough area of the inner wall to avoid laser ablation of wall material, an improved concept for cleaning windows between shots by means of laser ablation, and the identification of a new physics issue - nonlinear effects near a laser focus which could perturb the plasma density and temperature that are to be measured.

  3. Ultraviolet absorption hygrometer

    DOE Patents [OSTI]

    Gersh, M.E.; Bien, F.; Bernstein, L.S.

    1986-12-09

    An ultraviolet absorption hygrometer is provided including a source of pulsed ultraviolet radiation for providing radiation in a first wavelength region where water absorbs significantly and in a second proximate wavelength region where water absorbs weakly. Ultraviolet radiation in the first and second regions which has been transmitted through a sample path of atmosphere is detected. The intensity of the radiation transmitted in each of the first and second regions is compared and from this comparison the amount of water in the sample path is determined. 5 figs.

  4. Sandia Energy - Long-Path Absorption

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Long-Path Absorption Home Transportation Energy Predictive Simulation of Engines Diagnostics Gas-Phase Diagnostics Long-Path Absorption Long-Path AbsorptionAshley...

  5. SMB, X-ray Absorption Spectroscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Absorption Spectroscopy X-ray Absorption Spectroscopy X-ray absorption spectroscopy (XAS) is a well-established technique for simultaneous local geometric and electronic structure...

  6. Proposed ground-based incoherent Doppler lidar with iodine filter discriminator for atmospheric wind profiling

    SciTech Connect (OSTI)

    Liu, Z.S.; Chen, W.B.; Hair, J.W.; She, C.Y.

    1996-12-31

    A new incoherent lidar for measuring atmospheric wind using iodine molecular filter is proposed. A unique feature of the proposed lidar lies in its capability for simultaneous measurement of aerosol mixing ratio, with which the radial wind can be determined uniquely from lidar return. A preliminary laboratory experiment using a dye laser at 589 nm and a rotating wheel has been performed demonstrating the feasibility of the proposed wind measurement.

  7. Assessment and Optimization of Lidar Measurement Availability for Wind Turbine Control (Poster)

    SciTech Connect (OSTI)

    Scholbrock, F. A.; Fleming, P.; Wright, A.; Davoust, S.; Jehu, A.; Bouillet, M.; Bardon M.; Vercherin, B.

    2014-02-01

    Integrating Lidar to improve wind turbine controls is a potential breakthrough for reducing the cost of wind energy. By providing undisturbed wind measurements up to 400m in front of the rotor, Lidar may provide an accurate update of the turbine inflow with a preview time of several seconds. Focusing on loads, several studies have evaluated potential reductions using integrated Lidar, either by simulation or full scale field testing.

  8. LiDAR At Twenty-Nine Palms Area (Sabin, Et Al., 2010) | Open...

    Open Energy Info (EERE)

    Sabin, Et Al., 2010) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: LiDAR At Twenty-Nine Palms Area (Sabin, Et Al., 2010) Exploration Activity...

  9. Seasonal and optical characterisation of cirrus clouds over Indian sub-continent using LIDAR

    SciTech Connect (OSTI)

    Jayeshlal, G. S. Satyanarayana, Malladi Dhaman, Reji K. Motty, G. S.

    2014-10-15

    Light Detection and Ranging (LIDAR) is an important remote sensing technique to study about the cirrus clouds. The subject of cirrus clouds and related climate is challenging one. The received scattered signal from Lidar contains information on the physical and optical properties of cirrus clouds. The Lidar profile of the cirrus cloud provides information on the optical characteristics like depolarisation ratio, lidar ratio and optical depth, which give knowledge about possible phase, structure and orientation of cloud particle that affect the radiative budgeting of cirrus clouds. The findings from the study are subjected to generate inputs for better climatic modelling.

  10. ARM - Evaluation Product - MicroPulse LIDAR Cloud Optical Depth (MPLCOD)

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    ProductsMicroPulse LIDAR Cloud Optical Depth (MPLCOD) ARM Data Discovery Browse Data Documentation Use the Data File Inventory tool to view data availability at the file level. Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : MicroPulse LIDAR Cloud Optical Depth (MPLCOD) The MPLCOD VAP retrieves the column cloud visible optical depth using LIDAR derived backscatter from the MPLNOR (Micro Pulse Lidar Normalized Backscatter) and

  11. LiDAR At Glass Buttes Area (DOE GTP) | Open Energy Information

    Open Energy Info (EERE)

    Glass Buttes Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: LiDAR At Glass Buttes Area (DOE GTP) Exploration Activity Details...

  12. LiDAR At Gabbs Valley Area (DOE GTP) | Open Energy Information

    Open Energy Info (EERE)

    Gabbs Valley Area (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: LiDAR At Gabbs Valley Area (DOE GTP) Exploration Activity Details...

  13. Two-frequency lidar technique for mesospheric Na temperature measurements

    SciTech Connect (OSTI)

    She, C.Y.; Latifi, H.; Yu, J.R.; Alvarez, R.J. II ); Bills, R.E.; Gardner, C.S. )

    1990-06-01

    The authors describe a new two-frequency lidar for measuring Na temperature profiles that uses a stabilized cw single-mode dye laser oscillator (rms frequency jitter < 1 MHz) followed by a pulsed-dye power amplifier (140 MHz FWHM linewidth) which is pumped by an injection-locked Nd:YAG laser. The laser oscillator is tuned to the two operating frequencies by observing the Doppler-free structure of the Na D{sub 2} fluorescence spectrum in a vapor cells. The lidar technique and the initial observations of the temperature profile between 82 and 102 km at Ft. Collins, CO (40.6{degree}N,105{degree}W) are described. Absolute temperature accuracies at the Na layer peak of better than {plus minus}3 K with a vertical resolution of 1 km and an integration period of approximately 5 min were achieved.

  14. Doppler Lidar Vertical Velocity Statistics Value-Added Product

    SciTech Connect (OSTI)

    Newsom, RK; Sivaraman, C; Shippert, TR; Riihimaki, LD

    2015-07-01

    fluctuations are crucial for improved understanding of turbulent mixing and diffusion, convective initiation, and cloud life cycles. The Atmospheric Radiation Measurement (ARM) Climate Research Facility operates coherent Doppler lidar systems at several sites around the globe. These instruments provide measurements of clear-air vertical velocity profiles in the lower troposphere with a nominal temporal resolution of 1 sec and height resolution of 30 m. The purpose of the Doppler lidar vertical velocity statistics (DLWSTATS) value-added product (VAP) is to produce height- and time-resolved estimates of vertical velocity variance, skewness, and kurtosis from these raw measurements. The VAP also produces estimates of cloud properties, including cloud-base height (CBH), cloud frequency, cloud-base vertical velocity, and cloud-base updraft fraction.

  15. Lidar Inter-Comparison Exercise Final Campaign Report A Protat

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Lidar Inter-Comparison Exercise Final Campaign Report A Protat S Young February 2015 DOE/SC-ARM-15-008 DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use

  16. Doppler Lidar Vertical Velocity Statistics Value-Added Product

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    49 Doppler Lidar Vertical Velocity Statistics Value-Added Product RK Newsom C Sivaraman TR Shippert LD Riihimaki July 2015 DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or

  17. Arctic Mixed-Phase Cloud Properties from AERI Lidar Observations: Algorithm and Results from SHEBA

    SciTech Connect (OSTI)

    Turner, David D.

    2005-04-01

    A new approach to retrieve microphysical properties from mixed-phase Arctic clouds is presented. This mixed-phase cloud property retrieval algorithm (MIXCRA) retrieves cloud optical depth, ice fraction, and the effective radius of the water and ice particles from ground-based, high-resolution infrared radiance and lidar cloud boundary observations. The theoretical basis for this technique is that the absorption coefficient of ice is greater than that of liquid water from 10 to 13 ?m, whereas liquid water is more absorbing than ice from 16 to 25 ?m. MIXCRA retrievals are only valid for optically thin (?visible < 6) single-layer clouds when the precipitable water vapor is less than 1 cm. MIXCRA was applied to the Atmospheric Emitted Radiance Interferometer (AERI) data that were collected during the Surface Heat Budget of the Arctic Ocean (SHEBA) experiment from November 1997 to May 1998, where 63% of all of the cloudy scenes above the SHEBA site met this specification. The retrieval determined that approximately 48% of these clouds were mixed phase and that a significant number of clouds (during all 7 months) contained liquid water, even for cloud temperatures as low as 240 K. The retrieved distributions of effective radii for water and ice particles in single-phase clouds are shown to be different than the effective radii in mixed-phase clouds.

  18. First detection of a noctilucent cloud by lidar

    SciTech Connect (OSTI)

    Hansen, G.; Serwazi, M.; von Zahn, U. )

    1989-12-01

    During the night of August 5/6, 1989 for the first time a noctilucent cloud (NLC) was detected and measured by a lidar instrument. The observations were made with ground-based narrow-band Na lidar located at Andenes, Norway (69{degree}N, 16{degree}E geographic coordinates). In wavelength the lidar was operated both at the Na D{sub 2} resonance line of 589 nm as well as 5 Doppler widths shifted away. The altitude resolution was 200 m. The NLC developed at about 22:20 UT, reached its maximum backscatter cross section at 23:05 UT and became unobservable at around 00:10 UT. During this period the NLC exhibited the following properties: (a) its altitude ranged between 83.4 and 82.2 km; (b) its full width at half maximum ranged between 1.4 and 0.3 km; (c) the ratio of measured backscatter intensity from the NLC to the calculated Rayleigh signal from 82.6 km reached 450; (d) its volume backscatter cross section maximized at 6.5 {times} 10{sup {minus}9} m{sup {minus}1} sr{sup {minus}1}.

  19. Lidar arc scan uncertainty reduction through scanning geometry optimization

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, H.; Barthelmie, R. J.; Pryor, S. C.; Brown, G.

    2015-10-07

    Doppler lidars are frequently operated in a mode referred to as arc scans, wherein the lidar beam scans across a sector with a fixed elevation angle and the resulting measurements are used to derive an estimate of the n minute horizontal mean wind velocity (speed and direction). Previous studies have shown that the uncertainty in the measured wind speed originates from turbulent wind fluctuations and depends on the scan geometry (the arc span and the arc orientation). This paper is designed to provide guidance on optimal scan geometries for two key applications in the wind energy industry: wind turbine powermoreperformance analysis and annual energy production. We present a quantitative analysis of the retrieved wind speed uncertainty derived using a theoretical model with the assumption of isotropic and frozen turbulence, and observations from three sites that are onshore with flat terrain, onshore with complex terrain and offshore, respectively. The results from both the theoretical model and observations show that the uncertainty is scaled with the turbulence intensity such that the relative standard error on the 10 min mean wind speed is about 30 % of the turbulence intensity. The uncertainty in both retrieved wind speeds and derived wind energy production estimates can be reduced by aligning lidar beams with the dominant wind direction, increasing the arc span and lowering the number of beams per arc scan. Large arc spans should be used at sites with high turbulence intensity and/or large wind direction variation when arc scans are used for wind resource assessment.less

  20. ARM: 10-minute Raman Lidar: aerosol depolarization profiles and single layer cloud optical depths from first Turner algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    1998-03-01

    10-minute Raman Lidar: aerosol depolarization profiles and single layer cloud optical depths from first Turner algorithm

  1. ARM: ARSCL: cloud base height from first Clothiaux algorithms on Vaisala or Belfort ceilometers, Micropulse lidar, and MMCR

    SciTech Connect (OSTI)

    Karen Johnson; Michael Jensen

    1996-11-08

    ARSCL: cloud base height from first Clothiaux algorithms on Vaisala or Belfort ceilometers, Micropulse lidar, and MMCR

  2. ARM: 10-minute Raman Lidar: aerosol depolarization profiles and single layer cloud optical depths from first Turner algorithm

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Chitra Sivaraman; Connor Flynn

    10-minute Raman Lidar: aerosol depolarization profiles and single layer cloud optical depths from first Turner algorithm

  3. ARM: ARSCL: cloud base height from first Clothiaux algorithms on Vaisala or Belfort ceilometers, Micropulse lidar, and MMCR

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Karen Johnson; Michael Jensen

    ARSCL: cloud base height from first Clothiaux algorithms on Vaisala or Belfort ceilometers, Micropulse lidar, and MMCR

  4. Turbine Reliability and Operability Optimization through the use of Direct Detection Lidar Final Technical Report

    SciTech Connect (OSTI)

    Johnson, David K; Lewis, Matthew J; Pavlich, Jane C; Wright, Alan D; Johnson, Kathryn E; Pace, Andrew M

    2013-02-01

    The goal of this Department of Energy (DOE) project is to increase wind turbine efficiency and reliability with the use of a Light Detection and Ranging (LIDAR) system. The LIDAR provides wind speed and direction data that can be used to help mitigate the fatigue stress on the turbine blades and internal components caused by wind gusts, sub-optimal pointing and reactionary speed or RPM changes. This effort will have a significant impact on the operation and maintenance costs of turbines across the industry. During the course of the project, Michigan Aerospace Corporation (MAC) modified and tested a prototype direct detection wind LIDAR instrument; the resulting LIDAR design considered all aspects of wind turbine LIDAR operation from mounting, assembly, and environmental operating conditions to laser safety. Additionally, in co-operation with our partners, the National Renewable Energy Lab and the Colorado School of Mines, progress was made in LIDAR performance modeling as well as LIDAR feed forward control system modeling and simulation. The results of this investigation showed that using LIDAR measurements to change between baseline and extreme event controllers in a switching architecture can reduce damage equivalent loads on blades and tower, and produce higher mean power output due to fewer overspeed events. This DOE project has led to continued venture capital investment and engagement with leading turbine OEMs, wind farm developers, and wind farm owner/operators.

  5. Subgap Absorption in Conjugated Polymers

    DOE R&D Accomplishments [OSTI]

    Sinclair, M.; Seager, C. H.; McBranch, D.; Heeger, A. J; Baker, G. L.

    1991-01-01

    Along with X{sup (3)}, the magnitude of the optical absorption in the transparent window below the principal absorption edge is an important parameter which will ultimately determine the utility of conjugated polymers in active integrated optical devices. With an absorptance sensitivity of < 10{sup {minus}5}, Photothermal Deflection Spectroscopy (PDS) is ideal for determining the absorption coefficients of thin films of transparent'' materials. We have used PDS to measure the optical absorption spectra of the conjugated polymers poly(1,4-phenylene-vinylene) (and derivitives) and polydiacetylene-4BCMU in the spectral region from 0.55 eV to 3 eV. Our spectra show that the shape of the absorption edge varies considerably from polymer to polymer, with polydiacetylene-4BCMU having the steepest absorption edge. The minimum absorption coefficients measured varied somewhat with sample age and quality, but were typically in the range 1 cm{sup {minus}1} to 10 cm{sup {minus}1}. In the region below 1 eV, overtones of C-H stretching modes were observed, indicating that further improvements in transparency in this spectral region might be achieved via deuteration of fluorination.

  6. The rediscovery of absorption chillers

    SciTech Connect (OSTI)

    Katzel, J.

    1992-04-23

    Absorption chillers are back - and for two very good reasons: they are environmentally sound and, in many cases, economically attractive. One factor fueling this resurgence is the outlook for natural gas, the energy source of most absorption systems. Deregulation has spurred exploration, and forecasts indicate an abundant supply and relatively low prices through 2050. Threats of global warming and depletion of the ozone layer also are forces driving the absorption chiller market. Being a good corporate citizen today means minimizing or eliminating the use of chlorofluorocarbons (CFCs), the basis of many refrigerants used in mechanical chillers. Even as chemical and chiller manufacturers alike work to develop substitute refrigerants, the perfect alternative has yet to be found. Absorption units are free of these problems, a benefit that appeals to many people.

  7. Using CO2 Lidar for Standoff Detection of a Perfluorocarbon Tracer in Air

    SciTech Connect (OSTI)

    Heiser,J.H.; Smith, S.; Sedlacek, A.

    2008-02-06

    The Tag, Track and Location System Program (TTL) is investigating the use of PFTs as tracers for tagging and tracking items of interest or fallen soldiers. In order for the tagging and tracking to be valuable there must be a location system that can detect the PFTs. This report details the development of an infrared lidar platform for standoff detection of PFTs released into the air from a tagged object or person. Furthering work performed using a table top lidar system in an indoor environment; a mobile mini lidar platform was assembled using an existing Raman lidar platform, a grating tunable CO{sub 2} IR laser, Judson HgCdTe detector and miscellaneous folding optics and electronics. The lidar achieved {approx}200 ppb-m sensitivity in laboratory and indoor testing and was then successfully demonstrated at an outdoor test. The lidar system was able to detect PFTs released into a vehicle from a distance of 100 meters. In its final, fully optimized configuration the lidar was capable of repeatedly detecting PFTs in the air released from tagged vehicles. Responses were immediate and clear. This report details the results of a proof-of-concept demonstration for standoff detection of a perfluorocarbon tracer (PFT) using infrared lidar. The project is part of the Tag, Track and Location System Program and was performed under a contract with Tracer Detection Technology Corp. with funding from the Office of Naval Research. A lidar capable of detecting PFT releases at distance was assembled by modifying an existing Raman lidar platform by incorporating a grating tunable CO{sub 2} IR laser, Judson HgCdTe detector and miscellaneous folding optics and electronics. The lidar achieved {approx}200 ppb-m sensitivity in laboratory and indoor testing and was successfully demonstrated at an outdoor test. The demonstration test (scripted by the sponsor) consisted of three parked cars, two of which were tagged with the PFT. The cars were located 70 (closest) to 100 meters (farthest) from the lidar (the lidar beam path was limited by site constraints and was {approx}100 meters). When one door of each of the cars was opened (sequentially), the lidar was clearly able to determine which vehicles had been tagged and which one was not. The lidar is probably capable of greater than 0.5 kilometer standoff distances based on the extreme amount of signal return achieved (so much that the system had to be de-tuned). The BNL lidar system, while optimized to the extent possible with available parts and budget, was not as sensitive as it could be. Steps to improve the lidar are detailed in this report and include using a better laser system (for more stable power output), dual wavelengths (to improve the sensitivity and allow common mode noise reduction and to allow the use of the lidar in a scanning configuration), heterodyning (for range resolved PFT detection) and an off-axis optical configuration (for improved near field sensitivity).

  8. Wind Measurements from Arc Scans with Doppler Wind Lidar

    SciTech Connect (OSTI)

    Wang, H.; Barthelmie, R. J.; Clifton, Andy; Pryor, S. C.

    2015-11-25

    When defining optimal scanning geometries for scanning lidars for wind energy applications, we found that it is still an active field of research. Our paper evaluates uncertainties associated with arc scan geometries and presents recommendations regarding optimal configurations in the atmospheric boundary layer. The analysis is based on arc scan data from a Doppler wind lidar with one elevation angle and seven azimuth angles spanning 30° and focuses on an estimation of 10-min mean wind speed and direction. When flow is horizontally uniform, this approach can provide accurate wind measurements required for wind resource assessments in part because of its high resampling rate. Retrieved wind velocities at a single range gate exhibit good correlation to data from a sonic anemometer on a nearby meteorological tower, and vertical profiles of horizontal wind speed, though derived from range gates located on a conical surface, match those measured by mast-mounted cup anemometers. Uncertainties in the retrieved wind velocity are related to high turbulent wind fluctuation and an inhomogeneous horizontal wind field. Moreover, the radial velocity variance is found to be a robust measure of the uncertainty of the retrieved wind speed because of its relationship to turbulence properties. It is further shown that the standard error of wind speed estimates can be minimized by increasing the azimuthal range beyond 30° and using five to seven azimuth angles.

  9. Wind Measurements from Arc Scans with Doppler Wind Lidar

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Wang, H.; Barthelmie, R. J.; Clifton, Andy; Pryor, S. C.

    2015-11-25

    When defining optimal scanning geometries for scanning lidars for wind energy applications, we found that it is still an active field of research. Our paper evaluates uncertainties associated with arc scan geometries and presents recommendations regarding optimal configurations in the atmospheric boundary layer. The analysis is based on arc scan data from a Doppler wind lidar with one elevation angle and seven azimuth angles spanning 30° and focuses on an estimation of 10-min mean wind speed and direction. When flow is horizontally uniform, this approach can provide accurate wind measurements required for wind resource assessments in part because of itsmore » high resampling rate. Retrieved wind velocities at a single range gate exhibit good correlation to data from a sonic anemometer on a nearby meteorological tower, and vertical profiles of horizontal wind speed, though derived from range gates located on a conical surface, match those measured by mast-mounted cup anemometers. Uncertainties in the retrieved wind velocity are related to high turbulent wind fluctuation and an inhomogeneous horizontal wind field. Moreover, the radial velocity variance is found to be a robust measure of the uncertainty of the retrieved wind speed because of its relationship to turbulence properties. It is further shown that the standard error of wind speed estimates can be minimized by increasing the azimuthal range beyond 30° and using five to seven azimuth angles.« less

  10. NOAA lidar observations during the TMDBCE lethality test at WSMR on 5 February 1993. Technical memo

    SciTech Connect (OSTI)

    Post, M.J.; Olivier, L.D.

    1996-03-01

    The National Oceanic and Atomospheric Administration`s (NOAA) pulsed CO2 Doppler lidar successfully tracked a cloud of liquid triethyl phosphate (TEP) released from an incoming Storm missile. By concentrating on the lowest portion of the cloud, information about the descent of the TEP cloud was obtained. TEP cloud bottom height and a ground track showing the motion of the cloud relative to the lidar were plotted. In addition, lidar measurements were used to guide an instrumented air craft into the cloud. Improvements for future tests were defined.

  11. Ultraviolet high-spectral-resolution Doppler lidar for measuring wind field and aerosol optical properties

    SciTech Connect (OSTI)

    Imaki, Masaharu; Kobayashi, Takao

    2005-10-01

    An ultraviolet incoherent Doppler lidar that incorporates the high-spectral-resolution (HSR) technique has been developed for measuring the wind field and aerosol optical properties in the troposphere. An injection seeded and tripled Nd:YAG laser at an ultraviolet wavelength of 355 nm was used in the lidar system. The HRS technique can resolve the aerosol Mie backscatter and the molecular Rayleigh backscatter to derive the signal components. By detecting the Mie backscatter, a great increase in the Doppler filter sensitivity was realized compared to the conventional incoherent Doppler lidars that detected the Rayleigh backscatter. The wind velocity distribution in a two-dimensional cross section was measured. By using the HSR technique, multifunction and absolute value measurements were realized for aerosol extinction, and volume backscatter coefficients; the laser beam transmittance, the lidar ratio, and the backscatter ratio are derived from these measurements.

  12. 2 micron LIDAR for laser-based remote sensing: Flight demonstration and application survey

    SciTech Connect (OSTI)

    Wagener, T.J.; Demma, N.; Kmetec, J.D.; Kubo, T.S.

    1995-02-01

    A flight test of a diode-pumped solid-state 2 micron Doppler Light Detection And Ranging (LIDAR) system was conducted on-board the NASA Ames DC-8 Airborne Laboratory. This was the first ever airborne demonstration of a 2 micron diode-pumped solid-state Doppler LIDAR. The LIDAR performance was verified by comparing the true-airspeed (TAS) estimate with that found using the pneumatic air data system; excellent agreement was found. The capabilities of this pulsed 2 micron Doppler LIDAR system include high bandwidth air data determination without the need for extensive forebody calibration, remote wind profiling as far as several kilometers away from the aircraft, eye-safe laser transmission at 2 micron, and diode-pumped solid-state design for compact construction and reliable performance. 7 refs.

  13. Structural Analysis of Southern Dixie Valley using LiDAR and...

    Open Energy Info (EERE)

    and characterize young faults, high resolution LiDAR and 1:12,000-scale low-sun-angle (LSA) aerial photography was acquired for the NAS Fallon study area. The LSA photos were...

  14. DOE/SC-ARM/TR-100 Raman Lidar Profiles Best Estimate Value-Added...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    state or reflect those of the U.S. Government or any agency thereof. DOESC-ARMTR-100 Raman Lidar Profiles Best Estimate Value-Added Product Technical Report R Newsom...

  15. Novel polarization-sensitive micropulse lidar measurement technique

    SciTech Connect (OSTI)

    Flynn, Connor J.; Mendoza, Albert; Zheng, Yunhui; Mathur, Savyasachee

    2007-03-19

    Polarization-sensitive detection of elastic backscatter is useful for detection of cloud phase and depolarizing aerosols. The U.S. DOE Atmospheric Radiation Measurements (ARM) Program has deployed micropulse lidar (MPL) for over a decade, but without polarized detection. Adding an actively-controlled liquid crystal retarder provides the capability to identify depolarizing particles by alternately transmitting linearly and circularly polarized light. This represents a departure from established techniques which transmit exclusively linear polarization or exclusively circular polarization. Mueller matrix calculations yield simple relationships between the well-known linear depolarization ratio δlinear, the circular depolarization ratio δcirc, and the hybrid MPL depolarization ratio δMPL. This research was supported by the Office of Biological and Environmental Research of the U.S. Department of Energy as part of the Atmospheric Radiation Measurement Program.

  16. Performance of a VME-based parallel processing LIDAR data acquisition system (summary)

    SciTech Connect (OSTI)

    Moore, K.; Buttler, B.; Caffrey, M.; Soriano, C.

    1995-05-01

    It may be possible to make accurate real time, autonomous, 2 and 3 dimensional wind measurements remotely with an elastic backscatter Light Detection and Ranging (LIDAR) system by incorporating digital parallel processing hardware into the data acquisition system. In this paper, we report the performance of a commercially available digital parallel processing system in implementing the maximum correlation technique for wind sensing using actual LIDAR data. Timing and numerical accuracy are benchmarked against a standard microprocessor impementation.

  17. Retrieval of Urban Boundary Layer Structures from Doppler Lidar Data. Part I: Accuracy Assessment

    SciTech Connect (OSTI)

    Xia, Quanxin; Lin, Ching Long; Calhoun, Ron; Newsom, Rob K.

    2008-01-01

    Two coherent Doppler lidars from the US Army Research Laboratory (ARL) and Arizona State University (ASU) were deployed in the Joint Urban 2003 atmospheric dispersion field experiment (JU2003) held in Oklahoma City. The dual lidar data are used to evaluate the accuracy of the four-dimensional variational data assimilation (4DVAR) method and identify the coherent flow structures in the urban boundary layer. The objectives of the study are three-fold. The first objective is to examine the effect of eddy viscosity models on the quality of retrieved velocity data. The second objective is to determine the fidelity of single-lidar 4DVAR and evaluate the difference between single- and dual-lidar retrievals. The third objective is to correlate the retrieved flow structures with the ground building data. It is found that the approach of treating eddy viscosity as part of control variables yields better results than the approach of prescribing viscosity. The ARL single-lidar 4DVAR is able to retrieve radial velocity fields with an accuracy of 98% in the along-beam direction and 80-90% in the cross-beam direction. For the dual-lidar 4DVAR, the accuracy of retrieved radial velocity in the ARL cross-beam direction improves to 90-94%. By using the dual-lidar retrieved data as a reference, the single-lidar 4DVAR is able to recover fluctuating velocity fields with 70-80% accuracy in the along-beam direction and 60-70% accuracy in the cross-beam direction. Large-scale convective roll structures are found in the vicinity of downtown airpark and parks. Vortical structures are identified near the business district. Strong updrafts and downdrafts are also found above a cluster of restaurants.

  18. Absorption-heat-pump system

    DOE Patents [OSTI]

    Grossman, G.; Perez-Blanco, H.

    1983-06-16

    An improvement in an absorption heat pump cycle is obtained by adding adiabatic absorption and desorption steps to the absorber and desorber of the system. The adiabatic processes make it possible to obtain the highest temperature in the absorber before any heat is removed from it and the lowest temperature in the desorber before heat is added to it, allowing for efficient utilization of the thermodynamic availability of the heat supply stream. The improved system can operate with a larger difference between high and low working fluid concentrations, less circulation losses, and more efficient heat exchange than a conventional system.

  19. Transient absorption spectroscopy of laser shocked explosives

    SciTech Connect (OSTI)

    Mcgrane, Shawn D; Dang, Nhan C; Whitley, Von H; Bolome, Cindy A; Moore, D S

    2010-01-01

    Transient absorption spectra from 390-890 nm of laser shocked RDX, PETN, sapphire, and polyvinylnitrate (PVN) at sub-nanosecond time scales are reported. RDX shows a nearly linear increase in absorption with time after shock at {approx}23 GPa. PETN is similar, but with smaller total absorption. A broad visible absorption in sapphire begins nearly immediately upon shock loading but does not build over time. PVN exhibits thin film interference in the absorption spectra along with increased absorption with time. The absorptions in RDX and PETN are suggested to originate in chemical reactions happening on picosecond time scales at these shock stresses, although further diagnostics are required to prove this interpretation.

  20. Absorption Cooling Basics | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    Absorption coolers use heat rather than electricity as their energy source. Because natural gas is the most common heat source for absorption cooling, it is also referred to as gas-fired cooling. Other potential heat sources include propane, solar-heated water, or geothermal-heated water. Although mainly used in industrial or commercial settings, absorption coolers are commercially available for large residential homes. How Absorption Cooling Works An absorption cooling cycle relies on three

  1. Cooperation on Lidar for Improved Wind Turbine Performance. Cooperative Research and Development Final Report, CRADA Number CRD-13-521

    SciTech Connect (OSTI)

    Fleming, Paul

    2015-05-12

    Research into the use of lidar for improved wind turbine performance is an area of considerable interest. Lidars have been proposed to analyze and improve wind turbine pitch control performance, yaw alignment and control performance, as well as to improve power curve assessments. In this CRADA, NREL, NRG Systems, Inc. (“NRG”) and Avent Lidar Technology SAS (“Avent”) will collaborate on testing these concepts.

  2. Photodetector with enhanced light absorption

    DOE Patents [OSTI]

    Kane, James (Lawrenceville, NJ)

    1985-01-01

    A photodetector including a light transmissive electrically conducting layer having a textured surface with a semiconductor body thereon. This layer traps incident light thereby enhancing the absorption of light by the semiconductor body. A photodetector comprising a textured light transmissive electrically conducting layer of SnO.sub.2 and a body of hydrogenated amorphous silicon has a conversion efficiency about fifty percent greater than that of comparative cells. The invention also includes a method of fabricating the photodetector of the invention.

  3. GAX absorption cycle design process

    SciTech Connect (OSTI)

    Priedeman, D.K.; Christensen, R.N.

    1999-07-01

    This paper presents an absorption system design process that relies on computer simulations that are validated by experimental findings. An ammonia-water absorption heat pump cycle at 3 refrigeration tons (RT) and chillers at 3.3 RT and 5 RT (10.5 kW, 11.6 kW, and 17.6 kW) were initially modeled and then built and tested. The experimental results were used to calibrate both the cycle simulation and the component simulations, yielding computer design routines that could accurately predict component and cycle performance. Each system was a generator-absorber heat exchange (GAX) cycle, and all were sized for residential and light commercial use, where very little absorption equipment is currently used. The specific findings of the 5 RT (17.6 kW) chiller are presented. Modeling incorporated a heat loss from the gas-fired generator and pressure drops in both the evaporator and absorber. Simulation results and experimental findings agreed closely and validated the modeling method and simulation software.

  4. Purge needs in absorption chillers

    SciTech Connect (OSTI)

    Murray, J.G. )

    1993-10-01

    Absorption chillers are regaining a significant share of large tonnage chiller sales, such as they had 20 years ago. Gas-fired chillers are now available that have a base energy (ultimate fuel usage) consumption rate per ton comparable to that in electric units. Effective purging in an absorption chiller is an absolute necessity to achieve the low chilled water temperature needed for dehumidification and to fully benefit from the energy savings offered by double-effect cycles. Although the purge system is usually not shown on the typical cycle schematic, its proper functioning is a key requirement for satisfactory machine operation. This article discusses the effect of noncondensible (N/C) gases on the absorption cooling process and the basics of purge systems. In addition, the article discusses the rationale for the important design step of selecting the location of the N/C probe, and discusses purge systems applicable to the direct-fired, double-effect machines now entering the marketplace.

  5. Absorption Cooling Basics | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    Absorption coolers use heat rather than electricity as their energy source. Because natural gas is the most common heat source for absorption cooling, it is also referred to as...

  6. Lidar-measured winds from space: A key component for weather and climate prediction

    SciTech Connect (OSTI)

    Baker, W.E.; Emmitt, G.D.; Robertson, F.

    1995-06-01

    The deployment of a space-based Doppler lidar would provide information that is fundamental to advancing the understanding and prediction of weather and climate. This paper reviews the concepts of wind measurement by Doppler lidar, highlights the results of some observing system simulation experiments with lidar winds, and discusses the important advances in earth system science anticipated with lidar winds. Observing system simulation experiments, conducted using two different general circulation models, have shown (1) that there is a significant improvement in the forecast accuracy over the Southern Hemisphere and tropical oceans resulting from the assimilation of simulated satellite wind data, and (2) that wind data are significantly more effective than temperature or moisture data in controlling analysis error. Because accurate wind observations are currently almost entirely unavailable for the vast majority of tropical cyclones worldwide, lidar winds have the potential to substantially improve tropical cyclone forecasts. Similarly, to improve water vapor flux divergence calculations, a direct measure of the ageostrophic wind is needed since the present level of uncertainty cannot be reduced with better temperature and moisture soundings alone. 99 refs., 10 figs., 3 tabs.

  7. Automated retrieval of cloud and aerosol properties from the ARM Raman lidar, part 1: feature detection

    SciTech Connect (OSTI)

    Thorsen, Tyler J.; Fu, Qiang; Newsom, Rob K.; Turner, David D.; Comstock, Jennifer M.

    2015-11-01

    A Feature detection and EXtinction retrieval (FEX) algorithm for the Atmospheric Radiation Measurement (ARM) program’s Raman lidar (RL) has been developed. Presented here is part 1 of the FEX algorithm: the detection of features including both clouds and aerosols. The approach of FEX is to use multiple quantities— scattering ratios derived using elastic and nitro-gen channel signals from two fields of view, the scattering ratio derived using only the elastic channel, and the total volume depolarization ratio— to identify features using range-dependent detection thresholds. FEX is designed to be context-sensitive with thresholds determined for each profile by calculating the expected clear-sky signal and noise. The use of multiple quantities pro-vides complementary depictions of cloud and aerosol locations and allows for consistency checks to improve the accuracy of the feature mask. The depolarization ratio is shown to be particularly effective at detecting optically-thin features containing non-spherical particles such as cirrus clouds. Improve-ments over the existing ARM RL cloud mask are shown. The performance of FEX is validated against a collocated micropulse lidar and observations from the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) satellite over the ARM Darwin, Australia site. While we focus on a specific lidar system, the FEX framework presented here is suitable for other Raman or high spectral resolution lidars.

  8. Incoherent Doppler lidar for measurement of atmospheric winds

    SciTech Connect (OSTI)

    Skinner, W.R.; Hays, P.B.

    1994-12-31

    A conceptual space-based incoherent Doppler lidar wind measurement system is described. The system employs a Fabry-Perot interferometer to detect the Doppler shift of the backscattered laser line, and uses two channels, one for aerosol and one for molecular backscatter. Previous investigations have considered only the aerosol backscatter as the means to determine the Doppler shift. Several studies have demonstrated that aerosol backscatter, particularly over the oceans and in the southern hemisphere, can be extremely low in the free troposphere. The two channel configuration permits acceptable measurements regardless of the aerosol loading. The system operates in the near UV, which is eye safe and provides a large molecular backscatter. With a 20 Watt laser, 1 meter diameter collecting telescope, and 5 seconds integration time, the horizontal line of sight wind errors would be less than 1 m/s with aerosols typical of a continental loading from the surface to the stratosphere. Areas of low aerosol loading would have errors of about 3 m/s.

  9. Advanced regenerative absorption refrigeration cycles

    DOE Patents [OSTI]

    Dao, Kim

    1990-01-01

    Multi-effect regenerative absorption cycles which provide a high coefficient of performance (COP) at relatively high input temperatures. An absorber-coupled double-effect regenerative cycle (ADR cycle) (10) is provided having a single-effect absorption cycle (SEA cycle) (11) as a topping subcycle and a single-effect regenerative absorption cycle (1R cycle) (12) as a bottoming subcycle. The SEA cycle (11) includes a boiler (13), a condenser (21), an expansion device (28), an evaporator (31), and an absorber (40), all operatively connected together. The 1R cycle (12) includes a multistage boiler (48), a multi-stage resorber (51), a multisection regenerator (49) and also uses the condenser (21), expansion device (28) and evaporator (31) of the SEA topping subcycle (11), all operatively connected together. External heat is applied to the SEA boiler (13) for operation up to about 500 degrees F., with most of the high pressure vapor going to the condenser (21) and evaporator (31) being generated by the regenerator (49). The substantially adiabatic and isothermal functioning of the SER subcycle (12) provides a high COP. For higher input temperatures of up to 700 degrees F., another SEA cycle (111) is used as a topping subcycle, with the absorber (140) of the topping subcycle being heat coupled to the boiler (13) of an ADR cycle (10). The 1R cycle (12) itself is an improvement in that all resorber stages (50b-f) have a portion of their output pumped to boiling conduits (71a-f) through the regenerator (49), which conduits are connected to and at the same pressure as the highest pressure stage (48a) of the 1R multistage boiler (48).

  10. Absorption Heat Pumps | Department of Energy

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Heat & Cool » Heat Pump Systems » Absorption Heat Pumps Absorption Heat Pumps Absorption heat pumps are essentially air-source heat pumps driven not by electricity, but by a heat source such as natural gas, propane, solar-heated water, or geothermal-heated water. Because natural gas is the most common heat source for absorption heat pumps, they are also referred to as gas-fired heat pumps. There are also absorption (or gas-fired) coolers available that work on the same principle. Unlike

  11. Measurements of Wind and Turbulence Profiles with Scanning Doppler Lidar for Wind Energy Applications

    SciTech Connect (OSTI)

    Frehlich, R.; Kelley, N.

    2008-03-01

    High-quality profiles of mean and turbulent statistics of the wind field upstream of a wind farm can be produced using a scanning Doppler lidar. Careful corrections for the spatial filtering of the wind field by the lidar pulse produce turbulence estimates equivalent to point sensors but with the added advantage of a larger sampling volume to increase the statistical accuracy of the estimates. For a well-designed lidar system, this permits accurate estimates of the key turbulent statistics over various subdomains and with sufficiently short observation times to monitor rapid changes in conditions. These features may be ideally suited for optimal operation of wind farms and also for improved resource assessment of potential sites.

  12. Reduction of the pulse spike-cut error in Fourier-deconvolved lidar profiles

    SciTech Connect (OSTI)

    Stoyanov, D.V.; Gurdev, L.L.; Dreischuh, T.N.

    1996-08-01

    A simple approach is analyzed and applied to the National Oceanic and Atmospheric Administration (NOAA) Doppler lidar data to reduce the error in Fourier-deconvolved lidar profiles that is caused by spike-cut uncertainty in the laser pulse shape, i.e., uncertainty of the type of not well-recorded (cut, missed) pulse spikes. Such a type of uncertainty is intrinsic to the case of TE (TEA) CO{sub 2} laser transmitters. This approach requires only an estimate of the spike area to be known. The result from the analytical estimation of error reduction is in agreement with the results from the NOAA lidar data processing and from computer simulation. {copyright} {ital 1996 Optical Society of America.}

  13. The lidar dark band: An oddity of the radar bright band analogy

    SciTech Connect (OSTI)

    Sassen, K.

    1996-04-01

    Although much has sbeen learned from independent radar and lidar studies of atmospheric precipitations, occasionally supported by aircraft profiling, what has been lacking is combined optical, microwave, and insitu observations of the melting layer. Fortunately, the rainshowers on April 21, 1994, during the Remote Cloud Sensing intensive obervations Period (RCSIOP) at the Southern Great Plains Cloud and radiation Testbed (CART) site provided an opportunity for coordinated dual-wavelength University of Utah Polarization Diversity Lidar, University of Massachusetts Cloud Profiling Radar System Doppler Radar, and the University of North Dakota Citation aircraft measurements.

  14. Cirrus cloud-temperature interactions over a tropical station, Gadanki from lidar and satellite observations

    SciTech Connect (OSTI)

    S, Motty G Satyanarayana, M. Krishnakumar, V. Dhaman, Reji k.

    2014-10-15

    The cirrus clouds play an important role in the radiation budget of the earth's atmospheric system and are important to characterize their vertical structure and optical properties. LIDAR measurements are obtained from the tropical station Gadanki (13.5{sup 0} N, 79.2{sup 0} E), India, and meteorological indicators derived from Radiosonde data. Most of the cirrus clouds are observed near to the tropopause, which substantiates the strength of the tropical convective processes. The height and temperature dependencies of cloud height, optical depth, and depolarization ratio were investigated. Cirrus observations made using CALIPSO satellite are compared with lidar data for systematic statistical study of cirrus climatology.

  15. Olefin recovery via chemical absorption

    SciTech Connect (OSTI)

    Barchas, R.

    1998-06-01

    The recovery of fight olefins in petrochemical plants has generally been accomplished through cryogenic distillation, a process which is very capital and energy intensive. In an effort to simplify the recovery process and reduce its cost, BP Chemicals has developed a chemical absorption technology based on an aqueous silver nitrate solution. Stone & Webster is now marketing, licensing, and engineering the technology. The process is commercially ready for recovering olefins from olefin derivative plant vent gases, such as vents from polyethylene, polypropylene, ethylene oxide, and synthetic ethanol units. The process can also be used to debottleneck C{sub 2} or C{sub 3} splinters, or to improve olefin product purity. This paper presents the olefin recovery imp technology, discusses its applications, and presents economics for the recovery of ethylene and propylene.

  16. Backscatter absorption gas imaging system

    DOE Patents [OSTI]

    McRae, Jr., Thomas G. (Livermore, CA)

    1985-01-01

    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 of an imager is irradiated by a laser. The imager receives both backscattered laser light and background radiation. When a detectable gas is present, the backscattered laser light is highly attenuated, producing a region of contrast or shadow on the image. A flying spot imaging system is utilized to synchronously irradiate and scan the area to lower laser power requirements. The imager signal is processed to produce a video display.

  17. Adjusting lidar-derived digital terrain models in coastal marshes based on estimated aboveground biomass density

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Medeiros, Stephen; Hagen, Scott; Weishampel, John; Angelo, James

    2015-03-25

    Digital elevation models (DEMs) derived from airborne lidar are traditionally unreliable in coastal salt marshes due to the inability of the laser to penetrate the dense grasses and reach the underlying soil. To that end, we present a novel processing methodology that uses ASTER Band 2 (visible red), an interferometric SAR (IfSAR) digital surface model, and lidar-derived canopy height to classify biomass density using both a three-class scheme (high, medium and low) and a two-class scheme (high and low). Elevation adjustments associated with these classes using both median and quartile approaches were applied to adjust lidar-derived elevation values closer tomore » true bare earth elevation. The performance of the method was tested on 229 elevation points in the lower Apalachicola River Marsh. The two-class quartile-based adjusted DEM produced the best results, reducing the RMS error in elevation from 0.65 m to 0.40 m, a 38% improvement. The raw mean errors for the lidar DEM and the adjusted DEM were 0.61 ± 0.24 m and 0.32 ± 0.24 m, respectively, thereby reducing the high bias by approximately 49%.« less

  18. Active probing of cloud thickness and optical depth using wide-angle imaging LIDAR.

    SciTech Connect (OSTI)

    Love, Steven P.; Davis, A. B.; Rohde, C. A.; Tellier, L. L.; Ho, Cheng,

    2002-01-01

    At most optical wavelengths, laser light in a cloud lidar experiment is not absorbed but merely scattered out of the beam, eventually escaping the cloud via multiple scattering. There is much information available in this light scattered far from the input beam, information ignored by traditional 'on-beam' lidar. Monitoring these off-beam returns in a fully space- and time-resolved manner is the essence of our unique instrument, Wide Angle Imaging Lidar (WAIL). In effect, WAIL produces wide-field (60{sup o} full-angle) 'movies' of the scattering process and records the cloud's radiative Green functions. A direct data product of WAIL is the distribution of photon path lengths resulting from multiple scattering in the cloud. Following insights from diffusion theory, we can use the measured Green functions to infer the physical thickness and optical depth of the cloud layer. WAIL is notable in that it is applicable to optically thick clouds, a regime in which traditional lidar is reduced to ceilometry. Section 2 covers the up-to-date evolution of the nighttime WAIL instrument at LANL. Section 3 reports our progress towards daytime capability for WAIL, an important extension to full diurnal cycle monitoring by means of an ultra-narrow magneto-optic atomic line filter. Section 4 describes briefly how the important cloud properties can be inferred from WAIL signals.

  19. Upstream Measurements of Wind Profiles with Doppler Lidar for Improved Wind Energy Integration

    SciTech Connect (OSTI)

    Rodney Frehlich

    2012-10-30

    New upstream measurements of wind profiles over the altitude range of wind turbines will be produced using a scanning Doppler lidar. These long range high quality measurements will provide improved wind power forecasts for wind energy integration into the power grid. The main goal of the project is to develop the optimal Doppler lidar operating parameters and data processing algorithms for improved wind energy integration by enhancing the wind power forecasts in the 30 to 60 minute time frame, especially for the large wind power ramps. Currently, there is very little upstream data at large wind farms, especially accurate wind profiles over the full height of the turbine blades. The potential of scanning Doppler lidar will be determined by rigorous computer modeling and evaluation of actual Doppler lidar data from the WindTracer system produced by Lockheed Martin Coherent Technologies, Inc. of Louisville, Colorado. Various data products will be investigated for input into numerical weather prediction models and statistically based nowcasting algorithms. Successful implementation of the proposed research will provide the required information for a full cost benefit analysis of the improved forecasts of wind power for energy integration as well as the added benefit of high quality wind and turbulence information for optimal control of the wind turbines at large wind farms.

  20. Turbine-scale wind field measurements using dual-Doppler lidar

    SciTech Connect (OSTI)

    Newsom, Rob K.; Berg, Larry K.; Shaw, William J.; Fischer, Marc

    2015-02-01

    Spatially resolved measurements of micro-scale winds are retrieved using scanning dual-Doppler lidar, and validated against independent in situ wind measurements. Data for this study were obtained during a month-long field campaign conducted at a site in north-central Oklahoma in November of 2010. Observational platforms include one heavily instrumented 60-m meteorological tower and two scanning coherent Doppler lidars. The lidars were configured to perform coordinated dual-Doppler scans surrounding the 60-m tower, and the resulting radial velocity observations were processed to retrieve the 3-component velocity vector field on surfaces defined by the intersecting scan planes. Raw radial velocity measurements from the lidars were calibrated by direct comparison to a sonic anemometer located at the 60 m level on the tower. Wind retrievals were performed using both calibrated and uncalibrated measurements, and validated against the 60-m sonic anemometer observations. Retrievals using uncalibrated radial velocity data show a significant slow bias in the wind speed of about 14%; whereas the retrievals using the calibrated data show a much smaller slow bias of 1.2%. Retrievals using either the calibrated or uncalibrated data exhibit negligible bias in the wind direction (<0.2o), and excellent correlation in the wind speeds (>0.96).

  1. Adjusting lidar-derived digital terrain models in coastal marshes based on estimated aboveground biomass density

    SciTech Connect (OSTI)

    Medeiros, Stephen; Hagen, Scott; Weishampel, John; Angelo, James

    2015-03-25

    Digital elevation models (DEMs) derived from airborne lidar are traditionally unreliable in coastal salt marshes due to the inability of the laser to penetrate the dense grasses and reach the underlying soil. To that end, we present a novel processing methodology that uses ASTER Band 2 (visible red), an interferometric SAR (IfSAR) digital surface model, and lidar-derived canopy height to classify biomass density using both a three-class scheme (high, medium and low) and a two-class scheme (high and low). Elevation adjustments associated with these classes using both median and quartile approaches were applied to adjust lidar-derived elevation values closer to true bare earth elevation. The performance of the method was tested on 229 elevation points in the lower Apalachicola River Marsh. The two-class quartile-based adjusted DEM produced the best results, reducing the RMS error in elevation from 0.65 m to 0.40 m, a 38% improvement. The raw mean errors for the lidar DEM and the adjusted DEM were 0.61 0.24 m and 0.32 0.24 m, respectively, thereby reducing the high bias by approximately 49%.

  2. Advanced Low Temperature Absorption Chiller Module Integrated...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Temperature Absorption Chiller Module Integrated with a CHP System at a Distributed Data Center - Presentation by Exergy Partners Corp., June 2011 Advanced Low Temperature ...

  3. Combining Feedback Absorption Spectroscopy, Amplified Resonance...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Feedback Absorption Spectroscopy, Amplified Resonance and Low Pressure Sampling for the Measurement of Nitrogen-Containing Compounds in Automotive Emissions Combining Feedback...

  4. Compact Absorption Chiller - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energy Efficiency Building Energy Efficiency Find More Like This Return to Search Compact Absorption Chiller Pacific Northwest National Laboratory Contact PNNL About This...

  5. An Analysis of Cloud Absorption During

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Analysis of Cloud Absorption During ARESE II (Spring 2000) D. M. Powell, R. T. Marchand, and T. P. Ackerman Pacific Northwest National Laboratory Richland, Washington Introduction...

  6. Cavity-Enhanced Transient Absorption Spectroscopy: Ultrafast...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Cavity-Enhanced Transient Absorption Spectroscopy: Ultrafast Spectroscopy goes Ultra-Sensitive Wednesday, November 11, 2015 - 3:00pm SLAC, Redtail Hawk Conference Room 108A...

  7. Detailed Hydrographic Feature Extraction from High-Resolution LiDAR Data

    SciTech Connect (OSTI)

    Danny L. Anderson

    2012-05-01

    Detailed hydrographic feature extraction from high-resolution light detection and ranging (LiDAR) data is investigated. Methods for quantitatively evaluating and comparing such extractions are presented, including the use of sinuosity and longitudinal root-mean-square-error (LRMSE). These metrics are then used to quantitatively compare stream networks in two studies. The first study examines the effect of raster cell size on watershed boundaries and stream networks delineated from LiDAR-derived digital elevation models (DEMs). The study confirmed that, with the greatly increased resolution of LiDAR data, smaller cell sizes generally yielded better stream network delineations, based on sinuosity and LRMSE. The second study demonstrates a new method of delineating a stream directly from LiDAR point clouds, without the intermediate step of deriving a DEM. Direct use of LiDAR point clouds could improve efficiency and accuracy of hydrographic feature extractions. The direct delineation method developed herein and termed mDn, is an extension of the D8 method that has been used for several decades with gridded raster data. The method divides the region around a starting point into sectors, using the LiDAR data points within each sector to determine an average slope, and selecting the sector with the greatest downward slope to determine the direction of flow. An mDn delineation was compared with a traditional grid-based delineation, using TauDEM, and other readily available, common stream data sets. Although, the TauDEM delineation yielded a sinuosity that more closely matches the reference, the mDn delineation yielded a sinuosity that was higher than either the TauDEM method or the existing published stream delineations. Furthermore, stream delineation using the mDn method yielded the smallest LRMSE.

  8. Transient simulation of absorption machines

    SciTech Connect (OSTI)

    Anand, D.K.; Allen, R.W.; Kumar, B.

    1982-08-01

    This paper presents a model for a water-cooled Lithium-Bromide/water absorption chiller and predicts its transient response both during the start-up phase and during the shutoff period. The simulation model incorporates such influencing factors as the thermodynamic properties of the working fluid, the absorbent, the heat-transfer configuration of different components of the chiller and related physical data. The time constants of different components are controlled by a set of key parameters that have been identified in this study. The results show a variable but at times significant amount of time delay before the chiller capacity gets close to its steady-state value. The model is intended to provide an insight into the mechanism of build-up to steady-state performance. By recognizing the significant factors contributing to transient degradation, steps can be taken to reduce such degradation. The evaluation of the residual capacity in the shut-off period will yield more realistic estimates of chiller COP for a chiller satisfying dynamic space cooling load.

  9. Transient simulation of absorption machines

    SciTech Connect (OSTI)

    Anand, D.K.; Allen, R.W.; Kumar, B.

    1982-08-01

    This paper presents a model for a water-cooled Lithium-Bromide/water absorption chiller and predicts its transient response both during the start-up phase and during the shutoff period. The simulation model incorporates such influencing factors as the thermodynamic properties of the working fluid, the absorbent, the heat-transfer configuration of different components of the chiller and related physical data. The time constants of different components are controlled by a set of key parameters that have been identified in this study. The results show a variable but at times significant amount of time delay before the chiller capacity gets close to its steadystate value. The model is intended to provide an insight into the mechanism of build-up to steady-state performance. By recognizing the significant factors contributing to transient degradation, steps can be taken to reduce such degradation. The evaluation of the residual capacity in the shut-off period will yield more realistic estimates of chiller COP for a chiller satisfying dynamic space cooling load.

  10. Novel absorption detection techniques for capillary electrophoresis

    SciTech Connect (OSTI)

    Xue, Y.

    1994-07-27

    Capillary electrophoresis (CE) has emerged as one of the most versatile separation methods. However, efficient separation is not sufficient unless coupled to adequate detection. The narrow inner diameter (I.D.) of the capillary column raises a big challenge to detection methods. For UV-vis absorption detection, the concentration sensitivity is only at the {mu}M level. Most commercial CE instruments are equipped with incoherent UV-vis lamps. Low-brightness, instability and inefficient coupling of the light source with the capillary limit the further improvement of UV-vis absorption detection in CE. The goals of this research have been to show the utility of laser-based absorption detection. The approaches involve: on-column double-beam laser absorption detection and its application to the detection of small ions and proteins, and absorption detection with the bubble-shaped flow cell.

  11. Absorption of carbonyl sulfide in aqueous methyldiethanolamine

    SciTech Connect (OSTI)

    Al-Ghawas, H.A.; Ruiz-Ibanez, G.; Sandall, O.C. (Dept. of Chemical and Nuclear Engineering, Univ. of California, Santa Barbara, CA (US))

    1988-01-01

    The absorption of carbonyl sulfide in aqueous methyldiethanolamine (MDEA) was studied over a range of temperatures and MDEA concentrations. MDEA is commonly used for selective absorption of hydrogen sulfide in the presence of carbon dioxide. However, sulfur in the form of COS may also be present and it is necessary that estimates of absorption rates of this compound be made. The objective of this study is to determine the physiochemical properties needed to predict COS absorption rates in aqueous MDEA. Free gas solubility and the diffusivity of COS in MDEA solutions were measured over the temperature range 15 to 40{sup 0}C for MDEA concentrations up to 30 weight per cent using the nitrous oxide analogy method. Solubilities were measured volumetrically in an equilibrium cell and diffusivities were measured using a laminar liquid jet absorber. The kinetics of the reaction between COS and MDEA were studied by measuring absorption rates in a single wetted-sphere absorber.

  12. Method to determine and adjust the alignment of the transmitter and receiver fields of view of a LIDAR system

    DOE Patents [OSTI]

    Schmitt, Randal L. (Tijeras, NM); Henson, Tammy D. (Albuquerque, NM); Krumel, Leslie J. (Cedar Crest, NM); Hargis, Jr., Philip J. (Albuquerque, NM)

    2006-06-20

    A method to determine the alignment of the transmitter and receiver fields of view of a light detection and ranging (LIDAR) system. This method can be employed to determine the far-field intensity distribution of the transmitter beam, as well as the variations in transmitted laser beam pointing as a function of time, temperature, or other environmental variables that may affect the co-alignment of the LIDAR system components. In order to achieve proper alignment of the transmitter and receiver optical systems when a LIDAR system is being used in the field, this method employs a laser-beam-position-sensing detector as an integral part of the receiver optics of the LIDAR system.

  13. Field Test Results of Using a Nacelle-Mounted Lidar for Improving Wind Energy Capture by Reducing Yaw Misalignment (Presentation)

    SciTech Connect (OSTI)

    Fleming, P.; Scholbrock, A.; Wright, A.

    2014-11-01

    Presented at the Nordic Wind Power Conference on November 5, 2014. This presentation describes field-test campaigns performed at the National Wind Technology Center in which lidar technology was used to improve the yaw alignment of the Controls Advanced Research Turbine (CART) 2 and CART3 wind turbines. The campaigns demonstrated that whether by learning a correction function to the nacelle vane, or by controlling yaw directly with the lidar signal, a significant improvement in power capture was demonstrated.

  14. Additional development of remote sensing techniques for observing morphology, microphysics, and radiative properties of clouds and tests using a new, robust CO{sub 2} lidar. Final report

    SciTech Connect (OSTI)

    Eberhard, W.L.; Brewer, W.A.; Intrieri, J.M.

    1998-09-28

    A three-year project with a goal of advancing CO{sub 2} lidar technology and measurement techniques for cloud studies was successfully completed. An eyesafe, infrared lidar with good sensitivity and improved Doppler accuracy was designed, constructed, and demonstrated. Dual-wavelength operation was achieved. A major leap forward in robustness was demonstrated. CO{sub 2} lidars were operated as part of two Intensive Operations Periods at the Southern Great Plains CART site. The first used an older lidar and was intended primarily for measurement technique development. The second used the new lidar and was primarily a demonstration and evaluation of its performance. Progress was demonstrated in the development, evaluation, and application of measurement techniques using CO{sub 2} lidar.

  15. Absorption chillers: Technology for the future

    SciTech Connect (OSTI)

    Garland, P.W.; Garland, R.W.

    1997-12-31

    In an era of heightened awareness of energy efficiency and the associated environmental impacts, many industries worldwide are exploring ``environmentally friendly`` technologies that provide equivalent or improved performance while reducing or eliminating harmful side-effects. The refrigeration and air-conditioning industry, due to its reliance on CFCs and HCFCs, has invested in research in alternatives to the industry standard vapor compression machines. One alternative technology with great promise is chemical absorption. Absorption chillers offer comparable refrigeration output with reduced SO{sub 2}, CO{sub 2}, and NO{sub x} emissions. Absorption chillers do not use CFCs or HCFCs, refrigerants that contribute to ozone depletion and global warming. Additionally, gas-fired absorption chillers can save significant amounts in energy costs when used in combination with a vapor compression chiller in a hybrid system. The hybrid system can take advantage of the comparatively low price of natural gas (per unit ton) and rely on the high performance of vapor compression when electricity prices are lower. The purpose of this article is to provide an introduction for those new to absorption technology as well as a discussion of selected high efficiency cycles, a discussion on the technology of coupling absorption with vapor compression systems to form a hybrid system, and the environmental impacts of absorption.

  16. Three dimensional winds: A maximum cross-correlation application to elastic lidar data

    SciTech Connect (OSTI)

    Buttler, W.T.

    1996-05-01

    Maximum cross-correlation techniques have been used with satellite data to estimate winds and sea surface velocities for several years. Los Alamos National Laboratory (LANL) is currently using a variation of the basic maximum cross-correlation technique, coupled with a deterministic application of a vector median filter, to measure transverse winds as a function of range and altitude from incoherent elastic backscatter lidar (light detection and ranging) data taken throughout large volumes within the atmospheric boundary layer. Hourly representations of three-dimensional wind fields, derived from elastic lidar data taken during an air-quality study performed in a region of complex terrain near Sunland Park, New Mexico, are presented and compared with results from an Environmental Protection Agency (EPA) approved laser doppler velocimeter. The wind fields showed persistent large scale eddies as well as general terrain-following winds in the Rio Grande valley.

  17. Absorption Heat Pumps | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    an ammonia-water absorption cycle to provide heating and cooling. As in a standard heat pump, the refrigerant (in this case, ammonia) is condensed in one coil to release its...

  18. Variable effect desorber-resorber absorption cycle

    DOE Patents [OSTI]

    Biermann, Wendell J. (Fayetteville, NY)

    1985-01-01

    An absorption refrigeration system has an intermediate temperature desorber-resorber pair. A valve between the desorber-resorber pair is modulated to control the capacity for load matching.

  19. Triple-effect absorption chiller cycles

    SciTech Connect (OSTI)

    DeVault, R.C. ); Grossman, G. )

    1992-01-01

    Gas-fired absorption chillers are widely used for air-conditioning buildings. Even the highest efficiency double-effect absorption chillers used more primary energy for air-conditioning buildings than the better electric chillers. Two different triple-effect absorption chiller cycles are capable of substantial performance improvement over equivalent double-effect cycles. One cycle uses two condensers and two absorbers to achieve the triple effect.'' A second cycle, the Double-Condenser Coupled Triple-Effect, uses three condensers as well as a third condenser subcooler (which exchanges heat with the lowest temperature first-effect generator). These triple-effect absorption cycles have the potential to be as energy efficient (on a primary fuel basis) as the best electric chillers. 19 refs.

  20. Absorption chillers: Part of the solution

    SciTech Connect (OSTI)

    Occhionero, A.J. ); Hughes, P.J. ); Reid, E.A. )

    1991-01-01

    Acid rain, ozone depletion, global warming, and implementation economics are considered as they relate to the advisability of expanding the application of absorption chillers. Introductory and background information are provided to put the discussion in the proper context. Then all four issues are discussed separately as they relate to absorption chillers. Acid rain and ozone depletion concerns, and implementation economics, are found to support the expanded use of absorption chillers. The global warming concern is found to be more of a gray area, but the areas of benefit correspond well with the conditions of greatest economic advantage. All things considered, absorption chillers are believed to be part of the environmental and economic solution. It is further believed that integrated resource planning (IRP) processes that consider electric and gas technologies on an equal footing would come to the same conclusion for many regions of the United States. 9 refs., 3 tabs.

  1. Triple-effect absorption chiller cycles

    SciTech Connect (OSTI)

    DeVault, R.C.; Grossman, G.

    1992-06-01

    Gas-fired absorption chillers are widely used for air-conditioning buildings. Even the highest efficiency double-effect absorption chillers used more primary energy for air-conditioning buildings than the better electric chillers. Two different triple-effect absorption chiller cycles are capable of substantial performance improvement over equivalent double-effect cycles. One cycle uses two condensers and two absorbers to achieve the ``triple effect.`` A second cycle, the Double-Condenser Coupled Triple-Effect, uses three condensers as well as a third condenser subcooler (which exchanges heat with the lowest temperature first-effect generator). These triple-effect absorption cycles have the potential to be as energy efficient (on a primary fuel basis) as the best electric chillers. 19 refs.

  2. Posters Long-Pathlength Infrared Absorption Measurements

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    3 Posters Long-Pathlength Infrared Absorption Measurements in the 8- to 14-m Atmospheric Window: Self-Broadening Coefficient Data T. J. Kulp (a) and J. Shinn Geophysics and...

  3. Raman Lidar Measurements of Aerosols and Water Vapor During the May 2003 Aerosol IOP

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Raman Lidar Measurements of Aerosols and Water Vapor During the May 2003 Aerosol IOP R. A. Ferrare National Aeronautics and Space Administration Langley Research Center Hampton, Virginia D. D. Turner Pacific Northwest National Laboratory Richland, Washington M. Clayton Science Applications International Corporation National Aeronautics and Space Administration Langley Research Center Hampton, Virginia B. S. Schmid and J. Redemann BAER/NASA Ames Research Institute Moffett Field, California D.

  4. DOE/SC-ARM/TR-120 Raman Lidar Profiles-Temperature

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    0 Raman Lidar Profiles-Temperature (RLPROFTEMP) Value-Added Product RK Newsom C Sivaraman SA McFarlane October 2012 DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents

  5. Linearly Organized Turbulence Structures Observed Over a Suburban Area by Dual-Doppler Lidar

    SciTech Connect (OSTI)

    Newsom, Rob K.; Calhoun, Ron; Ligon, David; Allwine, K Jerry

    2008-04-01

    Dual-Doppler lidar observations are used to investigate the structure and evolution of surface layer flow over a suburban area. The observations were made during the Joint Urban 2003 (JU2003) field experiment in Oklahoma City in the summer of 2003. This study focuses specifically on a 10-hour sequence of scan data beginning shortly after noon local time on July 7, 2003. During this period two coherent Doppler lidars performed overlapping low elevation angle sector scans upwind and south of Oklahoma Citys central business district (CBD). Radial velocity data from the two lidars are processed to reveal the structure and evolution of the horizontal velocity field in the surface layer throughout the afternoon and evening transition periods. The retrieved velocity fields clearly show a tendency for turbulence structures to be elongated in the direction of the mean flow throughout the entire 10-hour study period. As the stratification changed from unstable to weakly stable the turbulence structures became increasingly more linearly organized, and the cross-stream separation between high- and low-speed regoins decreased. The spatially resolved velocity fields are used to estimate streamwise and cross-stream turbulence length scales as functions of stability.

  6. Effects of hydrogen/deuterium absorption on the magnetic properties...

    Office of Scientific and Technical Information (OSTI)

    Effects of hydrogendeuterium absorption on the magnetic properties of CoPd multilayers Citation Details In-Document Search Title: Effects of hydrogendeuterium absorption on the...

  7. The Future of Absorption Technology in America: A Critical Look...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    The Future of Absorption Technology in America: A Critical Look at the Impact of Building, Cooling, Heating, and Power (BCHP) and Innovation, June 2000 The Future of Absorption...

  8. Integrated vacuum absorption steam cycle gas separation (Patent...

    Office of Scientific and Technical Information (OSTI)

    Integrated vacuum absorption steam cycle gas separation Citation Details In-Document Search Title: Integrated vacuum absorption steam cycle gas separation You are accessing a...

  9. Spectroscopic study of low-temperature hydrogen absorption in...

    Office of Scientific and Technical Information (OSTI)

    Spectroscopic study of low-temperature hydrogen absorption in palladium Citation Details In-Document Search Title: Spectroscopic study of low-temperature hydrogen absorption in...

  10. Origins of optical absorption characteristics of Cu2+ complexes...

    Office of Scientific and Technical Information (OSTI)

    Origins of optical absorption characteristics of Cu2+ complexes in solutions Citation Details In-Document Search Title: Origins of optical absorption characteristics of Cu2+ ...

  11. Absorption Spectra and Plotting Exciton Wavefunctions BerkeleyGW...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hands on Session 5: Converging Absorption Spectra and Plotting Exciton Wavefunctions BerkeleyGW Workshop 11232013 Diana Qiu Converging Absorption General Parameters: K-grid...

  12. Field testing of feedforward collective pitch control on the CART2 using a nacelle-based Lidar scanner

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Schlipf, David; Fleming, Paul; Haizmann, Florian; Scholbrock, Andrew; Hofsass, Martin; Wright, Alan; Cheng, Po Wen

    2014-01-01

    This work presents the results from a field test of LIDAR assisted collective pitch control using a scanning LIDAR device installed on the nacelle of a mid-scale research turbine. A nonlinear feedforward controller is extended by an adaptive filter to remove all uncorrelated frequencies of the wind speed measurement to avoid unnecessary control action. Positive effects on the rotor speed regulation as well as on tower, blade and shaft loads have been observed in the case that the previous measured correlation and timing between the wind preview and the turbine reaction are accomplish. The feedforward controller had negative impact, whenmore » the LIDAR measurement was disturbed by obstacles in front of the turbine. This work proves, that LIDAR is valuable tool for wind turbine control not only in simulations but also under real conditions. Moreover, the paper shows that further understanding of the relationship between the wind measurement and the turbine reaction is crucial to improve LIDAR assisted control of wind turbines.« less

  13. Simulating a 4-effect absorption chiller

    SciTech Connect (OSTI)

    Grossman, G.; Zaltash, A.; Adcock, P.W.; DeVault, R.C.

    1995-06-01

    Absorption chillers are heat-operated refrigeration machines that operate on one of the earliest known principles of refrigeration. Current absorption chillers typically use either steam or a gas-fired burner as the energy source. All current gas-fired absorption cooling systems are based on the well known single-effect or double-effect cycles. To further improve utilization of the high temperature heat available from natural gas, a variety of triple-effect cycles have been proposed and are being developed that are capable of substantial performance improvement over equivalent double-effect cycles. This article describes a study that investigated the possibility of even further improving utilization of the high temperature heat available from natural gas combustion. During the study, performance simulation was conducted for a 4-effect lithium bromide/water cycle. From an environmental perspective, absorption chillers provide several benefits. They use absorption pairs (such as lithium bromide/water) as the working fluids, rather than chlorofluorocarbons or hydrochlorofluorocarbons, which contribute to ozone depletion and global warming.

  14. Nanofibrous membrane-based absorption refrigeration system

    SciTech Connect (OSTI)

    Isfahani, RN; Sampath, K; Moghaddam, S

    2013-12-01

    This paper presents a study on the efficacy of highly porous nanofibrous membranes for application in membrane-based absorbers and desorbers. Permeability studies showed that membranes with a pore size greater than about one micron have a sufficient permeability for application in the absorber heat exchanger. Membranes with smaller pores were found to be adequate for the desorber heat exchanger. The membranes were implemented in experimental membrane-based absorber and desorber modules and successfully tested. Parametric studies were conducted on both absorber and desorber processes. Studies on the absorption process were focused on the effects of water vapor pressure, cooling water temperature, and the solution velocity on the absorption rate. Desorption studies were conducted on the effects of wall temperature, vapor and solution pressures, and the solution velocity on the desorption rate. Significantly higher absorption and desorption rates than in the falling film absorbers and desorbers were achieved. Published by Elsevier Ltd.

  15. Plasmon absorption modulator systems and methods

    DOE Patents [OSTI]

    Kekatpure, Rohan Deodatta; Davids, Paul

    2014-07-15

    Plasmon absorption modulator systems and methods are disclosed. A plasmon absorption modulator system includes a semiconductor substrate, a plurality of quantum well layers stacked on a top surface of the semiconductor substrate, and a metal layer formed on a top surface of the stack of quantum well layers. A method for modulating plasmonic current includes enabling propagation of the plasmonic current along a metal layer, and applying a voltage across the stack of quantum well layers to cause absorption of a portion of energy of the plasmonic current by the stack of quantum well layers. A metamaterial switching system includes a semiconductor substrate, a plurality of quantum well layers stacked on a top surface of the semiconductor substrate, and at least one metamaterial structure formed on a top surface of the stack of quantum well layers.

  16. Laser isotope separation by multiple photon absorption

    DOE Patents [OSTI]

    Robinson, C. Paul (Los Alamos, NM); Rockwood, Stephen D. (Los Alamos, NM); Jensen, Reed J. (Los Alamos, NM); Lyman, John L. (Los Alamos, NM); Aldridge, III, Jack P. (Los Alamos, NM)

    1987-01-01

    Multiple photon absorption from an intense beam of infrared laser light may be used to induce selective chemical reactions in molecular species which result in isotope separation or enrichment. The molecular species must have a sufficient density of vibrational states in its vibrational manifold that, is the presence of sufficiently intense infrared laser light tuned to selectively excite only those molecules containing a particular isotope, multiple photon absorption can occur. By this technique, for example, intense CO.sub.2 laser light may be used to highly enrich .sup.34 S in natural SF.sub.6 and .sup.11 B in natural BCl.sub.3.

  17. Laser isotope separation by multiple photon absorption

    DOE Patents [OSTI]

    Robinson, C.P.; Rockwood, S.D.; Jensen, R.J.; Lyman, J.L.; Aldridge, J.P. III.

    1987-04-07

    Multiple photon absorption from an intense beam of infrared laser light may be used to induce selective chemical reactions in molecular species which result in isotope separation or enrichment. The molecular species must have a sufficient density of vibrational states in its vibrational manifold that, is the presence of sufficiently intense infrared laser light tuned to selectively excite only those molecules containing a particular isotope, multiple photon absorption can occur. By this technique, for example, intense CO[sub 2] laser light may be used to highly enrich [sup 34]S in natural SF[sub 6] and [sup 11]B in natural BCl[sub 3]. 8 figs.

  18. Residential Absorption Heat Pump Water Heater | Department of Energy

    Energy Savers [EERE]

    Residential Absorption Heat Pump Water Heater Residential Absorption Heat Pump Water Heater Photo credit: Oak Ridge National Lab Photo credit: Oak Ridge National Lab Diagram of absorption heat pump water heater. <br /> Photo credit: Oak Ridge National Lab Diagram of absorption heat pump water heater. Photo credit: Oak Ridge National Lab Photo credit: Oak Ridge National Lab Diagram of absorption heat pump water heater. <br /> Photo credit: Oak Ridge National Lab Lead Performer: Oak

  19. Coupled dual loop absorption heat pump

    DOE Patents [OSTI]

    Sarkisian, Paul H. (Watertown, MA); Reimann, Robert C. (Lafayette, NY); Biermann, Wendell J. (Fayetteville, NY)

    1985-01-01

    A coupled dual loop absorption system which utilizes two separate complete loops. Each individual loop operates at three temperatures and two pressures. This low temperature loop absorber and condenser are thermally coupled to the high temperature loop evaporator, and the high temperature loop condenser and absorber are thermally coupled to the low temperature generator.

  20. Direct fired absorption machine flue gas recuperator

    DOE Patents [OSTI]

    Reimann, Robert C. (Lafayette, NY); Root, Richard A. (Spokane, WA)

    1985-01-01

    A recuperator which recovers heat from a gas, generally the combustion gas of a direct-fired generator of an absorption machine. The recuperator includes a housing with liquid flowing therethrough, the liquid being in direct contact with the combustion gas for increasing the effectiveness of the heat transfer between the gas and the liquid.

  1. Absorption machine with desorber-resorber

    DOE Patents [OSTI]

    Biermann, Wendell J. (Fayetteville, NY)

    1985-01-01

    An absorption refrigeration system utilizing a low temperature desorber and intermediate temperature resorber. The system operates at three temperatures and three pressures to increase the efficiency of the system and is capable of utilizing a lower generator temperature than previously used.

  2. Corrosion inhibitor for aqueous ammonia absorption system

    DOE Patents [OSTI]

    Phillips, Benjamin A. (Benton Harbor, MI); Whitlow, Eugene P. (St. Joseph, MI)

    1998-09-22

    A method of inhibiting corrosion and the formation of hydrogen and thus improving absorption in an ammonia/water absorption refrigeration, air conditioning or heat pump system by maintaining the hydroxyl ion concentration of the aqueous ammonia working fluid within a selected range under anaerobic conditions at temperatures up to 425.degree. F. This hydroxyl ion concentration is maintained by introducing to the aqueous ammonia working fluid an inhibitor in an amount effective to produce a hydroxyl ion concentration corresponding to a normality of the inhibitor relative to the water content ranging from about 0.015 N to about 0.2 N at 25.degree. C. Also, working fluids for inhibiting the corrosion of carbon steel and resulting hydrogen formation and improving absorption in an ammonia/water absorption system under anaerobic conditions at up to 425.degree. F. The working fluids may be aqueous solutions of ammonia and a strong base or aqueous solutions of ammonia, a strong base, and a specified buffer.

  3. Corrosion inhibitor for aqueous ammonia absorption system

    DOE Patents [OSTI]

    Phillips, B.A.; Whitlow, E.P.

    1998-09-22

    A method is described for inhibiting corrosion and the formation of hydrogen and thus improving absorption in an ammonia/water absorption refrigeration, air conditioning or heat pump system by maintaining the hydroxyl ion concentration of the aqueous ammonia working fluid within a selected range under anaerobic conditions at temperatures up to 425 F. This hydroxyl ion concentration is maintained by introducing to the aqueous ammonia working fluid an inhibitor in an amount effective to produce a hydroxyl ion concentration corresponding to a normality of the inhibitor relative to the water content ranging from about 0.015 N to about 0.2 N at 25 C. Also, working fluids for inhibiting the corrosion of carbon steel and resulting hydrogen formation and improving absorption in an ammonia/water absorption system under anaerobic conditions at up to 425 F. The working fluids may be aqueous solutions of ammonia and a strong base or aqueous solutions of ammonia, a strong base, and a specified buffer. 5 figs.

  4. Characterizing Aerosol Distributions and Optical Properties Using the NASA Langley High Spectral Resolution Lidar

    SciTech Connect (OSTI)

    Hostetler, Chris; Ferrare, Richard

    2013-02-14

    The objective of this project was to provide vertically and horizontally resolved data on aerosol optical properties to assess and ultimately improve how models represent these aerosol properties and their impacts on atmospheric radiation. The approach was to deploy the NASA Langley Airborne High Spectral Resolution Lidar (HSRL) and other synergistic remote sensors on DOE Atmospheric Science Research (ASR) sponsored airborne field campaigns and synergistic field campaigns sponsored by other agencies to remotely measure aerosol backscattering, extinction, and optical thickness profiles. Synergistic sensors included a nadir-viewing digital camera for context imagery, and, later in the project, the NASA Goddard Institute for Space Studies (GISS) Research Scanning Polarimeter (RSP). The information from the remote sensing instruments was used to map the horizontal and vertical distribution of aerosol properties and type. The retrieved lidar parameters include profiles of aerosol extinction, backscatter, depolarization, and optical depth. Products produced in subsequent analyses included aerosol mixed layer height, aerosol type, and the partition of aerosol optical depth by type. The lidar products provided vertical context for in situ and remote sensing measurements from other airborne and ground-based platforms employed in the field campaigns and was used to assess the predictions of transport models. Also, the measurements provide a data base for future evaluation of techniques to combine active (lidar) and passive (polarimeter) measurements in advanced retrieval schemes to remotely characterize aerosol microphysical properties. The project was initiated as a 3-year project starting 1 January 2005. It was later awarded continuation funding for another 3 years (i.e., through 31 December 2010) followed by a 1-year no-cost extension (through 31 December 2011). This project supported logistical and flight costs of the NASA sensors on a dedicated aircraft, the subsequent analysis and archival of the data, and the presentation of results in conferences, workshops, and publications. DOE ASR field campaigns supported under this project included - MAX-Mex /MILAGRO (2006) - TexAQS 2006/GoMACCS (2006) - CHAPS (2007) - RACORO (2009) - CARE/CalNex (2010) In addition, data acquired on HSRL airborne field campaigns sponsored by other agencies were used extensively to fulfill the science objectives of this project and the data acquired have been made available to other DOE ASR investigators upon request.

  5. Frequency agile laser safety & hazard analysis for the Sandia Remote Sensing System LIDAR.

    SciTech Connect (OSTI)

    Augustoni, Arnold L.

    2009-05-01

    A laser safety and hazard analysis was performed for the Raytheon Frequency Agile Laser (FAL) to be used with the Sandia Remote Sensing System (SRSS) B-70 Trailer based on the 2007 version of the American National Standards Institute's (ANSI) Standard 136.1, for Safe Use of Lasers and the 2005 version of the ANSI Standard Z136.6, for Safe Use of Lasers Outdoors. The B-70 SRSS LIDAR system is a portable platform, which is used to perform laser interaction experiments and tests at various national test sites.

  6. Lidar Investigation of Tropical Nocturnal Boundary Layer Aerosols and Cloud Macrophysics

    SciTech Connect (OSTI)

    Manoj, M. G.; Devara, PC S.; Taraphdar, Sourav

    2013-10-01

    Observational evidence of two-way association between nocturnal boundary layer aerosols and cloud macrophysical properties under different meteorological conditions is reported in this paper. The study has been conducted during 2008-09 employing a high space-time resolution polarimetric micro-pulse lidar over a tropical urban station in India. Firstly, the study highlights the crucial role of boundary layer aerosols and background meteorology on the formation and structure of low-level stratiform clouds in the backdrop of different atmospheric stability conditions. Turbulent mixing induced by the wind shear at the station, which is associated with a complex terrain, is found to play a pivotal role in the formation and structural evolution of nocturnal boundary layer clouds. Secondly, it is shown that the trapping of energy in the form of outgoing terrestrial radiation by the overlying low-level clouds can enhance the aerosol mixing height associated with the nocturnal boundary layer. To substantiate this, the long-wave heating associated with cloud capping has been quantitatively estimated in an indirect way by employing an Advanced Research Weather Research and Forecasting (WRF-ARW) model version 2.2 developed by National Center for Atmospheric Research (NCAR), Colorado, USA, and supplementary data sets; and differentiated against other heating mechanisms. The present investigation as well establishes the potential of lidar remote-sensing technique in exploring some of the intriguing aspects of the cloud-environment relationship.

  7. Lidar Measurements of the Vertical Distribution of Aerosol Optical and Physical Properties over Central Asia

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Chen, Boris B.; Sverdlik, Leonid G.; Imashev, Sanjar A.; Solomon, Paul A.; Lantz, Jeffrey; Schauer, James J.; Shafer, Martin M.; Artamonova, Maria S.; Carmichael, Gregory R.

    2013-01-01

    The vertical structure of aerosol optical and physical properties was measured by Lidar in Eastern Kyrgyzstan, Central Asia, from June 2008 to May 2009. Lidar measurements were supplemented with surface-based measurements of PM 2.5 and PM 10 mass and chemical composition in both size fractions. Dust transported into the region is common, being detected 33% of the time. The maximum frequency occurred in the spring of 2009. Dust transported to Central Asia comes from regional sources, for example, Taklimakan desert and Aral Sea basin, and from long-range transport, for example, deserts of Arabia, Northeast Africa, Iran, and Pakistan. Regionalmore » sources are characterized by pollution transport with maximum values of coarse particles within the planetary boundary layer, aerosol optical thickness, extinction coefficient, integral coefficient of aerosol backscatter, and minimum values of the Ångström exponent. Pollution associated with air masses transported over long distances has different characteristics during autumn, winter, and spring. During winter, dust emissions were low resulting in high values of the Ångström exponent (about 0.51) and the fine particle mass fraction (64%). Dust storms were more frequent during spring with an increase in coarse dust particles in comparison to winter. The aerosol vertical profiles can be used to lower uncertainty in estimating radiative forcing.« less

  8. Marine boundary layer structure as observed by space-based Lidar

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Luo, T.; Wang, Z.; Zhang, D.

    2015-12-03

    The marine boundary layer (MBL) structure is important to the exchange of heat, momentum, and moisture between oceans and the low atmosphere and to the marine low cloud processes. This paper explores MBL structure over the eastern Pacific region with a new 4 year satellite-based dataset. The MBL aerosol lidar backscattering from the CALIPSO (Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations) was used to identify the MBL top (BLH) and the mixing layer height (MLH). Results showed that MBL is generally decoupled with MLH / BLH ratio ranging from ? 0.5 to ? 0.8 and the MBL decoupling magnitude ismoremainly controlled by estimated inversion strength (EIS) that affects the cloud top entrainment process. The systematic differences between drizzling and non-drizzling stratocumulus tops, which may relate to the meso-scale circulations or gravity wave in MBL, also show dependence on EIS. Further analysis indicated that the MBL shows similar decoupled structure for clear sky and cumulus cloud-topped conditions, but is better mixed under stratiform cloud breakup and overcast conditions.less

  9. Integrated vacuum absorption steam cycle gas separation

    DOE Patents [OSTI]

    Chen, Shiaguo (Champaign, IL); Lu, Yonggi (Urbana, IL); Rostam-Abadi, Massoud (Champaign, IL)

    2011-11-22

    Methods and systems for separating a targeted gas from a gas stream emitted from a power plant. The gas stream is brought into contact with an absorption solution to preferentially absorb the targeted gas to be separated from the gas stream so that an absorbed gas is present within the absorption solution. This provides a gas-rich solution, which is introduced into a stripper. Low pressure exhaust steam from a low pressure steam turbine of the power plant is injected into the stripper with the gas-rich solution. The absorbed gas from the gas-rich solution is stripped in the stripper using the injected low pressure steam to provide a gas stream containing the targeted gas. The stripper is at or near vacuum. Water vapor in a gas stream from the stripper is condensed in a condenser operating at a pressure lower than the stripper to concentrate the targeted gas. Condensed water is separated from the concentrated targeted gas.

  10. Polaron absorption in amorphous tungsten oxide films

    SciTech Connect (OSTI)

    Berggren, Lars; Azens, Andris; Niklasson, Gunnar A.

    2001-08-15

    Amorphous thin films of tungsten oxide were deposited by sputtering onto glass substrates covered by conductive indium--tin oxide. The density and stoichiometry were determined by Rutherford backscattering spectrometry. Lithium ions were intercalated electrochemically into the films. The optical reflectance and transmittance were measured in the wavelength range from 0.3 to 2.5 {mu}m, at a number of intercalation levels. The polaron absorption peak becomes more symmetric and shifts to higher energies until an intercalation level of 0.25 to 0.3 Li{sup +}/W, where a saturation occurs. The shape of the polaron peak is in very good agreement with the theory of Bryksin [Fiz. Tverd. Tela 24, 1110 (1982)]. Within this model, the shift of the absorption peak is interpreted as an increase in the Fermi level of the material as more Li ions are inserted. {copyright} 2001 American Institute of Physics.

  11. Active probing of cloud multiple scattering, optical depth, vertical thickness, and liquid water content using wide-angle imaging LIDAR.

    SciTech Connect (OSTI)

    Love, Steven P.; Davis, A. B.; Rohde, C. A.; Tellier, L. L.; Ho, Cheng,

    2002-01-01

    At most optical wavelengths, laser light in a cloud lidar experiment is not absorbed but merely scattered out of the beam, eventually escaping the cloud via multiple scattering. There is much information available in this light scattered far from the input beam, information ignored by traditional 'on-beam' lidar. Monitoring these off-beam returns in a fully space- and time-resolved manner is the essence of our unique instrument, Wide Angle Imaging Lidar (WAIL). In effect, WAIL produces wide-field (60-degree full-angle) 'movies' of the scattering process and records the cloud's radiative Green functions. A direct data product of WAIL is the distribution of photon path lengths resulting from multiple scattering in the cloud. Following insights from diffusion theory, we can use the measured Green functions to infer the physical thickness and optical depth of the cloud layer, and, from there, estimate the volume-averaged liquid water content. WAIL is notable in that it is applicable to optically thick clouds, a regime in which traditional lidar is reduced to ceilometry. Here we present recent WAIL data oti various clouds and discuss the extension of WAIL to full diurnal monitoring by means of an ultra-narrow magneto-optic atomic line filter for daytime measurements.

  12. Field Test Results from Lidar Measured Yaw Control for Improved Yaw Alignment with the NREL Controls Advanced Research Turbine: Preprint

    SciTech Connect (OSTI)

    Scholbrock, A.; Fleming, P.; Wright, A.; Slinger, C.; Medley, J.; Harris, M.

    2014-12-01

    This paper describes field tests of a light detection and ranging (lidar) device placed forward looking on the nacelle of a wind turbine and used as a wind direction measurement to directly control the yaw position of a wind turbine. Conventionally, a wind turbine controls its yaw direction using a nacelle-mounted wind vane. If there is a bias in the measurement from the nacelle-mounted wind vane, a reduction in power production will be observed. This bias could be caused by a number of issues such as: poor calibration, electromagnetic interference, rotor wake, or other effects. With a lidar mounted on the nacelle, a measurement of the wind could be made upstream of the wind turbine where the wind is not being influenced by the rotor's wake or induction zone. Field tests were conducted with the lidar measured yaw system and the nacelle wind vane measured yaw system. Results show that a lidar can be used to effectively measure the yaw error of the wind turbine, and for this experiment, they also showed an improvement in power capture because of reduced yaw misalignment when compared to the nacelle wind vane measured yaw system.

  13. Radiation absorption properties of different plaster samples

    SciTech Connect (OSTI)

    Akkurt, Iskender; Guenoglu, Kadir; Mavi, Betuel; K Latin-Small-Letter-Dotless-I l Latin-Small-Letter-Dotless-I ncarslan, Semsettin; Seven, Aysun

    2012-09-06

    Although the plaster is one of the oldest known synthetic building materials, nowadays, it is used as interior coating of walls and ceilings of buildings. Thus measuring its radiation shielding properties is vital. For this purpose, radiation absorption properties of different plaster samples in this study. The measurements have been performed using gamma spectrometer system which connected to 3'' Multiplication-Sign 3''NaI (TI) detector.

  14. A New Model for Liquid Water Absorption

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Model for Liquid Water Absorption For original submission and image(s), see ARM Research Highlights http://www.arm.gov/science/highlights/ Research Highlight Liquid water path (LWP) is a critical measurement for a wide range of atmospheric studies, as the amount of liquid in a cloud is critical to understanding many cloud processes. For example, the radiative impact of the cloud (in both the longwave and shortwave portions of the spectrum) depends heavily on the LWP. Thus, the Atmospheric

  15. Field Testing of LIDAR-Assisted Feedforward Control Algorithms for Improved Speed Control and Fatigue Load Reduction on a 600-kW Wind Turbine: Preprint

    SciTech Connect (OSTI)

    Kumar, Avishek A.; Bossanyi, Ervin A.; Scholbrock, Andrew K.; Fleming, Paul; Boquet, Mathieu; Krishnamurthy, Raghu

    2015-12-14

    A severe challenge in controlling wind turbines is ensuring controller performance in the presence of a stochastic and unknown wind field, relying on the response of the turbine to generate control actions. Recent technologies such as LIDAR, allow sensing of the wind field before it reaches the rotor. In this work a field-testing campaign to test LIDAR Assisted Control (LAC) has been undertaken on a 600-kW turbine using a fixed, five-beam LIDAR system. The campaign compared the performance of a baseline controller to four LACs with progressively lower levels of feedback using 35 hours of collected data.

  16. Triple effect absorption chiller utilizing two refrigeration circuits

    SciTech Connect (OSTI)

    DeVault, R.C.

    1988-03-22

    This patent describes a heat absorption method for an absorption chiller. It comprises: providing a firs absorption system circuit for operation within a first temperature range, providing a second absorption system circuit for operation within a second temperature range; heat exchanging refrigerant and absorber solution; thermal communication with an external heat load. This patent describes a heat absorption apparatus for use as an absorption chiller. It includes: a first absorption system circuit for operation within a first temperature range; a second absorption system circuit for operation within a second temperature range which has a lower maximum temperature relative to the first temperature range; the first circuit having generator means, condenser means, evaporator means, and absorber means operatively connected together; the second circuit having generator means condenser means, evaporator means, and absorber means operative connected together; and the first circuit condenser means and the first circuit absorber means being in heat exchange communication with the second circuit generator means.

  17. Cloud Effects on Radiative Heating Rate Profiles over Darwin using ARM and A-train Radar/Lidar Observations

    SciTech Connect (OSTI)

    Thorsen, Tyler J.; Fu, Qiang; Comstock, Jennifer M.

    2013-06-11

    Observations of clouds from the ground-based U.S. Department of Energy Atmospheric Radiation Measurement program (ARM) and satellite-based A-train are used to compute cloud radiative forcing profiles over the ARM Darwin, Australia site. Cloud properties are obtained from both radar (the ARM Millimeter Cloud Radar (MMCR) and the CloudSat satellite in the A-train) and lidar (the ARM Micropulse lidar (MPL) and the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite in the A-train) observations. Cloud microphysical properties are taken from combined radar and lidar retrievals for ice clouds and radar only or lidar only retrievals for liquid clouds. Large, statistically significant differences of up to 1.43 K/day exist between the mean ARM and A-train net cloud radiative forcing profiles. The majority of the difference in cloud radiative forcing profiles is shown to be due to a large difference in the cloud fraction above 12 km. Above this altitude the A-train cloud fraction is significantly larger because more clouds are detected by CALIPSO than by the ground-based MPL. It is shown that the MPL is unable to observe as many high clouds as CALIPSO due to being more frequently attenuated and a poorer sensitivity even in otherwise clear-sky conditions. After accounting for cloud fraction differences and instrument sampling differences due to viewing platform we determined that differences in cloud radiative forcing due to the retrieved ice cloud properties is relatively small. This study demonstrates that A-train observations are better suited for the calculation cloud radiative forcing profiles. In addition, we find that it is necessary to supplement CloudSat with CALIPSO observations to obtain accurate cloud radiative forcing profiles since a large portion of clouds at Darwin are detected by CALIPSO only.

  18. Attosecond Electron Wave-Packet Interference Observed by Transient Absorption

    SciTech Connect (OSTI)

    Holler, M.; Schapper, F.; Gallmann, L.; Keller, U.

    2011-03-25

    We perform attosecond time-resolved transient absorption spectroscopy around the first ionization threshold of helium and observe rapid oscillations of the absorption of the individual harmonics as a function of time delay with respect to a superimposed, moderately strong infrared laser field. The phase relation between the absorption modulation of individual harmonics gives direct evidence for the interference of transiently bound electronic wave packets as the mechanism behind the absorption modulation.

  19. Hybrid absorption-adsorption carbon capture | Center for Gas

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    SeparationsRelevant to Clean Energy Technologies | Blandine Jerome Hybrid absorption-adsorption carbon capture

  20. Split-flow regeneration in absorptive air separation

    DOE Patents [OSTI]

    Weimer, R.F.

    1987-11-24

    A chemical absorptive separation of air in multiple stage of absorption and desorption is performed with partial recycle of absorbent between stages of desorption necessary to match equilibrium conditions in the various stages of absorption. This allows reduced absorbent flow, reduced energy demand and reduced capital costs. 4 figs.

  1. Split-flow regeneration in absorptive air separation

    DOE Patents [OSTI]

    Weimer, Robert F.

    1987-01-01

    A chemical absorptive separation of air in multiple stage of absorption and desorption is performed with partial recycle of absorbent between stages of desorption necessary to match equilibrium conditions in the various stages of absorption. This allows reduced absorbent flow, reduced energy demand and reduced capital costs.

  2. 44th Annual Anomalous Absorption Conference

    SciTech Connect (OSTI)

    Beg, Farhat

    2014-03-03

    Conference Grant Report July 14, 2015 Submitted to the U. S. Department of Energy Attn: Dr. Sean Finnegan By the University of California, San Diego 9500 Gilman Drive La Jolla, California 92093 On behalf of the 44th Annual Anomalous Absorption Conference 8-13 June 2014, in Estes Park, Colorado Support Requested: $10,100 Amount expended: $3,216.14 Performance Period: 1 March 20 14 to 28 February 20 15 Principal Investigator Dr. Farhat Beg Center for Energy Research University of California, San Diego 9500 Gilman Drive La Jolla, California 92093-0417 858-822-1266 (telephone) 858-534-4543 (fax) fbeg@ucsd.edu Administrative Point of Contact: Brandi Pate, 858-534-0851, blpate®ucsd.edu I. Background The forty-fourth Anomalous Absorption Conference was held in Estes Park, Colorado from June 5-8, 2014 (aac2014.ucsd.edu). The first Anomalous Absorption Conference was held in 1971 to assemble experts in the poorly understood area of laser-plasma absorption. The goal of that conference was to address the anomalously large laser absorption seen in plasma experiments with respect to the laser absorption predicted by linear plasma theory. Great progress in this research area has been made in the decades since that first meeting, due in part to the scientific interactions that have occurred annually at this conference. Specifically, this includes the development of nonlinear laser-plasma theory and the simulation of laser interactions with plasmas. Each summer since that first meeting, this week-long conference has been held at unique locations in North America as a scientific forum for intense scientific exchanges relevant to the interaction of laser radiation with plasmas. Responsibility for organizing the conference has traditional rotated each year between the major Inertial Confinement Fusion (ICF) laboratories and universities including LANL, LLNL, LLE, UCLA UC Davis and NRL. As the conference has matured over the past four decades, its technical footprint has expanded beyond ICF-related laser-plasma interactions to encompass closely related technical areas including laser particle acceleration, high-intensity laser effects, short­ pulse laser interactions, PIC and Vlasov/rad-hydro modeling, inertial and magnetic fusion plasmas, advanced plasma diagnostics, alternate ignition schemes, EOS/transport/opacity, and this year, x­ ray free-electron lasers and their applications. The conference continues to be a showcase for the presentation and discussion of the latest developments in these areas. II. Meeting Report The conference was extremely successful with more than one hundred participants. There were ninety-nine (99) abstracts submitted. There were forty-four (44) presentations including eleven (11) invited talks. The following topics were covered: a) Radiation Hydrodynamics b) Implosion Plasma Kinetic Effects c) Alternate Ignition Schemes d) Astrophysical Phenomena e) Opacity/Transport/EOS f) High Power Lasers and Facilities g) High-Intensity Laser-Matter Interactions h) Hydrodynamics and Hydro-instabilities i) Hot Dense Plasma Atomic Processes j) High Energy Density Physics k) Laser Particle Acceleration Physics l) Advanced Plasma Diagnostics m) Advanced light sources and applications Despite significant advertising, there were two students who applied for the travel grants: Charlie Jarrott and Joohwan Kim. The total funds expended were $3,216.14.

  3. Thermal model of solar absorption HVAC systems

    SciTech Connect (OSTI)

    Bergquam, J.B.; Brezner, J.M.

    1995-11-01

    This paper presents a thermal model that describes the performance of solar absorption HVAC systems. The model considers the collector array, the building cooling and heating loads, the absorption chiller and the high temperature storage. Heat losses from the storage tank and piping are included in the model. All of the results presented in the paper are for an array of flat plate solar collectors with black chrome (selective surface) absorber plates. The collector efficiency equation is used to calculate the useful heat output from the array. The storage is modeled as a non-stratified tank with polyurethane foam insulation. The system is assumed to operate continuously providing air conditioning during the cooling season, space heating during the winter and hot water throughout the year. The amount of heat required to drive the chiller is determined from the coefficient of performance of the absorption cycle. Results are presented for a typical COP of 0.7. The cooling capacity of the chiller is a function of storage (generator) temperature. The nominal value is 190 F (88 C) and the range of values considered is 180 F (82 C) to 210 F (99 C). Typical building cooling and heating loads are determined as a function of ambient conditions. Performance results are presented for Sacramento, CA and Washington, D.C. The model described in the paper makes use of National Solar Radiation Data Base (NSRDB) data and results are presented for these two locations. The uncertainties in the NSRDB are estimated to be in a range of 6% to 9%. This is a significant improvement over previously available data. The model makes it possible to predict the performance of solar HVAC systems and calculate quantities such as solar fraction, storage temperature, heat losses and parasitic power for every hour of the period for which data are available.

  4. Laser dynamics with excited-state absorption

    SciTech Connect (OSTI)

    Sanchez, F.; Kellou, A.

    1997-01-01

    The dynamics of a laser with excited-state absorption at the lasing wavelength is theoretically studied. The model is based on the rate equations for a four-level system. The stationary state is analytically calculated, permitting both the investigation of the laser characteristics and linear stability analysis. The latter shows that, in some conditions, the steady state is not stable in a particular range of pumping rates. However, a stable solution is restored for sufficiently high pumping rates. Stable self-pulsing solutions are obtained by numerical integration of the coupled equations. Also, the transient regimes are numerically analyzed. {copyright} 1997 Optical Society of America.

  5. Distributed Bragg Reflectors With Reduced Optical Absorption

    DOE Patents [OSTI]

    Klem, John F. (Albuquerque, NM)

    2005-08-16

    A new class of distributed Bragg reflectors has been developed. These distributed Bragg reflectors comprise interlayers positioned between sets of high-index and low-index quarter-wave plates. The presence of these interlayers is to reduce photon absorption resulting from spatially indirect photon-assisted electronic transitions between the high-index and low-index quarter wave plates. The distributed Bragg reflectors have applications for use in vertical-cavity surface-emitting lasers for use at 1.55 .mu.m and at other wavelengths of interest.

  6. Comparing Pulsed Doppler LIDAR with SODAR and Direct Measurements for Wind Assessment

    SciTech Connect (OSTI)

    Kelley, N. D.; Jonkman, B. J.; Scott, G. N.; Pichugina, Y. L.

    2007-07-01

    There is a pressing need for good wind-speed measurements at greater and greater heights to assess the availability of the resource in terms of power production and to identify any frequently occurring atmospheric structural characteristics that may create turbulence that impacts the operational reliability and lifetime of wind turbines and their components. In this paper, we summarize the results of a short study that compares the relative accuracies of wind speeds derived from a high-resolution pulsed Doppler LIDAR operated by the National Oceanic and Atmospheric Administration (NOAA) and a midrange Doppler SODAR with wind speeds measured by four levels of tower-based sonic anemometry up to a height of 116 m.

  7. Dilution cycle control for an absorption refrigeration system

    DOE Patents [OSTI]

    Reimann, Robert C. (Lafayette, NY)

    1984-01-01

    A dilution cycle control system for an absorption refrigeration system is disclosed. The control system includes a time delay relay for sensing shutdown of the absorption refrigeration system and for generating a control signal only after expiration of a preselected time period measured from the sensed shutdown of the absorption refrigeration system, during which the absorption refrigeration system is not restarted. A dilution cycle for the absorption refrigeration system is initiated in response to generation of a control signal by the time delay relay. This control system is particularly suitable for use with an absorption refrigeration system which is frequently cycled on and off since the time delay provided by the control system prevents needless dilution of the absorption refrigeration system when the system is turned off for only a short period of time and then is turned back on.

  8. Raman Lidar

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    While this technique is highly accurate, the retrieval is performed using signals from Raman-scattered light that is a weak scattering process. FEX uses an adaptive smoothing...

  9. Residential solar-absorption chiller thermal dynamics

    SciTech Connect (OSTI)

    Guertin, J.M.; Wood, B.D.; McNeill, B.W.

    1981-03-01

    Research is reported on the transient performance of a commercial residential 3 ton lithium bromide-water absorption chiller designed for solar firing. Emphasis was placed on separating the chiller response from that of the entire test facility so that its transient response could solely be observed and quantified. It was found that the entire system time response and thermal capacitance has a major impact on performance degradation due to transient operation. Tests run to ascertain computer algorithms which simulate system isolated chiller performance, revealed processes hitherto undocumented. Transient operation is simulated by three distinct algorithms associated with the three phases of chiller operation. The first phase is start up time. It was revealed during testing that the time required to reach steady state performance values, when the chiller was turned on, was a linear function of steady state water supply temperatures. The second phase is quasi steady state performance. Test facility's performance compared favorably with the manufacturer's published data. The third phase is the extra capacity produced during spin down. Spin down occurs when the hot water supply pump is turned off while the other system pumps remain operating for a few minutes, thus allowing extra chiller capacity to be realized. The computer algorithms were used to generate plots which show the operational surface of an isolated absorption chiller subjected to off design and transient operation.

  10. Solar absorption cooling plant in Seville

    SciTech Connect (OSTI)

    Bermejo, Pablo; Pino, Francisco Javier; Rosa, Felipe

    2010-08-15

    A solar/gas cooling plant at the Engineering School of Seville (Spain) was tested during the period 2008-2009. The system is composed of a double-effect LiBr + water absorption chiller of 174 kW nominal cooling capacity, powered by: (1) a pressurized hot water flow delivered by mean of a 352 m{sup 2} solar field of a linear concentrating Fresnel collector and (2) a direct-fired natural gas burner. The objective of the project is to indentify design improvements for future plants and to serve as a guideline. We focused our attention on the solar collector size and dirtiness, climatology, piping heat losses, operation control and coupling between solar collector and chiller. The daily average Fresnel collector efficiency was 0.35 with a maximum of 0.4. The absorption chiller operated with a daily average coefficient of performance of 1.1-1.25, where the solar energy represented the 75% of generator's total heat input, and the solar cooling ratio (quotient between useful cooling and insolation incident on the solar field) was 0.44. (author)

  11. Hydroxide absorption heat pumps with spray absorber

    SciTech Connect (OSTI)

    Summerer, F.; Alefeld, G.; Zeigler, F.; Riesch, P.

    1996-11-01

    The absorber is one of the most expensive components of an absorption heat pump or chiller, respectively. In order to reduce the cost of a heat exchanger, much effort is invested into searching for additives for heat transfer enhancement. Another way to reduce heat exchanger cost, especially for machines with low capacities, is to use an adiabatic spray absorber. The basic principles of the spray absorber is to perform heat and mass transfer separated from each other in two different components. In this way the heat can be rejected effectively in a liquid-liquid heat exchanger, whereas the mass transfer occurs subsequently in a simple vessel. The spray technique can not only save heat exchanger cost in conventional absorption systems working with water and lithium bromide, it also allows the use of quite different working fluids such as hydroxides, which have lower heat transfer coefficients in falling films. Moreover, the separated heat transfer can easily be performed in a liquid-to-air heat exchanger. Hence it is obvious to use hydroxides that allow for a high temperature lift for building an air-cooled chiller with spray absorber. In this presentation theoretical and experimental investigations of the spray absorber as well as the setup will be described. Finally, possible applications will be outlined.

  12. A RAPIDLY-TUNABLE ACOUSTO-OPTIC SPECTROMETER FOR A SPACE ENVIRONMENT

    SciTech Connect (OSTI)

    D. THOMPSON; C. HEWITT; C. WILSON

    2000-08-01

    As a complement to our work developing rapidly-tunable ({approximately}10-100 kHz) CO{sub 2} lasers for differential absorption lidar (DIAL) applications,l we have developed a rapidly-tunable spectrometer. A rapid spectral diagnostic is critical for a high speed DIAL system, since analysis of the return signals depends on knowing the spectral purity of the transmitted beam. The spectrometer developed for our lidar system is based on a double-passed large- (75 mm) aperture acousto-optic deflector, a grating, and a fast single-element room temperature mercury-cadmium-telluride detector. The spectrometer has a resolution of {approximately}0.5 cm{sup {minus}1}, a tuning range of 9.0-11.4 pm, a random-access tuning speed of greater than 80 kHz and a S/N ratio of greater than 100:1. We describe the design and performance of this device, as well as of future devices featuring improved resolution, higher speed and easier and more robust alignment. We will also briefly discuss the applications and limitations of the technique in a space environment.

  13. Gas separation using ultrasound and light absorption

    DOE Patents [OSTI]

    Sinha, Dipen N. (Los Alamos, NM)

    2012-07-31

    An apparatus and method for separating a chosen gas from a mixture of gases having no moving parts and utilizing no chemical processing is described. The separation of particulates from fluid carriers thereof has been observed using ultrasound. In a similar manner, molecular species may be separated from carrier species. It is also known that light-induced drift may separate light-absorbing species from carrier species. Therefore, the combination of temporally pulsed absorption of light with ultrasonic concentration is expected to significantly increase the efficiency of separation by ultrasonic concentration alone. Additionally, breaking the spatial symmetry of a cylindrical acoustic concentrator decreases the spatial distribution of the concentrated particles, and increases the concentration efficiency.

  14. Counterflow absorber for an absorption refrigeration system

    DOE Patents [OSTI]

    Reimann, Robert C. (Lafayette, NY)

    1984-01-01

    An air-cooled, vertical tube absorber for an absorption refrigeration system is disclosed. Strong absorbent solution is supplied to the top of the absorber and refrigerant vapor is supplied to the bottom of the absorber to create a direct counterflow of refrigerant vapor and absorbent solution in the absorber. The refrigeration system is designed so that the volume flow rate of refrigerant vapor in the tubes of the absorber is sufficient to create a substantially direct counterflow along the entire length of each tube in the absorber. This provides several advantages for the absorber such as higher efficiency and improved heat transfer characteristics, and allows improved purging of non-condensibles from the absorber.

  15. Enhanced light absorption of solar cells and photodetectors by diffraction

    DOE Patents [OSTI]

    Zaidi, Saleem H.; Gee, James M.

    2005-02-22

    Enhanced light absorption of solar cells and photodetectors by diffraction is described. Triangular, rectangular, and blazed subwavelength periodic structures are shown to improve performance of solar cells. Surface reflection can be tailored for either broadband, or narrow-band spectral absorption. Enhanced absorption is achieved by efficient optical coupling into obliquely propagating transmitted diffraction orders. Subwavelength one-dimensional structures are designed for polarization-dependent, wavelength-selective absorption in solar cells and photodetectors, while two-dimensional structures are designed for polarization-independent, wavelength-selective absorption therein. Suitable one and two-dimensional subwavelength periodic structures can also be designed for broadband spectral absorption in solar cells and photodetectors. If reactive ion etching (RIE) processes are used to form the grating, RIE-induced surface damage in subwavelength structures can be repaired by forming junctions using ion implantation methods. RIE-induced surface damage can also be removed by post RIE wet-chemical etching treatments.

  16. Continuous Light Absorption Photometer (CLAP) Final Campaign Report

    SciTech Connect (OSTI)

    Jefferson, Anne

    2014-05-01

    The Continuous Light Absorption Photometer (CLAP) measures the aerosol absorption of radiation at three visible wavelengths; 461, 522, and 653 nanometers (nm). Data from this measurement is used in radiative forcing calculations, atmospheric heating rates, and as a prediction of the amount of equivalent black carbon in atmospheric aerosol and in models of aerosol semi-direct forcing. Aerosol absorption measurements are essential to modeling the energy balance of the atmosphere.

  17. Light Absorption of Primary Organic Aerosol Paper Named ACS Editors...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Absorption of Primary Organic Aerosol Paper Named ACS Editors' Choice For original submission and image(s), see ARM Research Highlights http:www.arm.govsciencehighlights...

  18. Light Trapping, Absorption and Solar Energy Harvesting by Artificial...

    Office of Scientific and Technical Information (OSTI)

    Title: Light Trapping, Absorption and Solar Energy Harvesting by Artificial Materials We provide designs of thin-film solar cells utilizing optimized photonic-crystal ...

  19. X-ray transient absorption and picosecond IR spectroscopy of...

    Office of Scientific and Technical Information (OSTI)

    X-ray transient absorption and picosecond IR spectroscopy of fulvalene(tetracarbonyl)diruthenium on photoexcitation Citation Details In-Document Search Title: X-ray transient ...

  20. Absorption Heat Pump Water Heater - 2013 Peer Review | Department...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Photo credit: Oak Ridge National Lab Residential Absorption Heat Pump Water Heater Working Fluids Low Global Warming Potential Refrigerants - 2013 Peer Review Prioritization Tool - ...

  1. ITP Industrial Distributed Energy: The Future of Absorption Technology...

    Broader source: Energy.gov (indexed) [DOE]

    1 Ferdinand Carr Several factors have influenced absorption chiller sales since then. Natural gas prices, as well as, fuel availability concerns and governmental policies...

  2. Flexible flux plane simulations of parasitic absorption in nanoplasmon...

    Office of Scientific and Technical Information (OSTI)

    thin-film silicon solar cells Prev Next Title: Flexible flux plane simulations of parasitic absorption in nanoplasmonic thin-film silicon solar cells Authors: Chung, H. ...

  3. Electronic structure of titania aerogels: Soft x-ray absorption...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Electronic structure of titania aerogels: Soft x-ray absorption study Citation Details In-Document Search Title: Electronic structure of titania aerogels: Soft...

  4. Analysis of Doppler Lidar Data Acquired During the Pentagon Shield Field Campaign

    SciTech Connect (OSTI)

    Newsom, Rob K.

    2011-04-14

    Observations from two coherent Doppler lidars deployed during the Pentagon Shield field campaign are analyzed in conjunction with other sensors to characterize the overall boundary-layer structure, and identify the dominant flow characteristics during the entire two-week field campaign. Convective boundary layer (CBL) heights and cloud base heights (CBH) are estimated from an analysis of the lidar signal-to-noise-ratio (SNR), and mean wind profiles are computed using a modified velocity-azimuth-display (VAD) algorithm. Three-dimensional wind field retrievals are computed from coordinated overlapping volume scans, and the results are analyzed by visualizing the flow in horizontal and vertical cross sections. The VAD winds show that southerly flows dominate during the two-week field campaign. Low-level jets (LLJ) were evident on all but two of the nights during the field campaign. The LLJs tended to form a couple hours after sunset and reach maximum strength between 03 and 07 UTC. The surface friction velocities show distinct local maxima during four nights when strong LLJs formed. Estimates of the convective boundary layer height and residual layer height are obtained through an analysis of the vertical gradient of the lidar signal-to-noise-ratio (SNR). Strong minimum in the SNR gradient often develops just above the surface after sunrise. This minimum is associated with the developing CBL, and increases rapidly during the early portion of the daytime period. On several days, this minimum continues to increase until about sunset. Secondary minima in the SNR gradient were also observed at higher altitudes, and are believed to be remnants of the CBL height from previous days, i.e. the residual layer height. The dual-Doppler analysis technique used in this study makes use of hourly averaged radial velocity data to produce three-dimensional grids of the horizontal velocity components, and the horizontal velocity variance. Visualization of horizontal and vertical cross sections of the dual-Doppler wind retrievals often indicated a jet-like flow feature over the Potomac River under southerly flow conditions. This linear flow feature is roughly aligned with the Potomac River corridor to the south of the confluence with the Anatostia River, and is most apparent at low levels (i.e. below ~150 m MSL). It is believed that this flow arises due to reduced drag over the water surface and when the large scale flow aligns with the Potomac River corridor. A so-called area-constrained VAD analysis generally confirmed the observations from the dual-Doppler analysis. When the large scale flow is southerly, wind speeds over the Potomac River are consistently larger than the at a site just to the west of the river for altitudes less than 100 m MSL. Above this level, the trend is somewhat less obvious. The data suggest that the depth of the wind speed maximum may be reduced by strong directional shear aloft.

  5. Cost reduction in absorption chillers: Phase 2

    SciTech Connect (OSTI)

    Leigh, R.W.

    1989-02-01

    A research program at Brookhaven National Laboratory (BNL) has addressed the possibility of dramatically lowering the first costs of absorption chillers through lowered material intensity and the use of lower cost materials, primarily in the heat exchangers which make up the bulk of the operating components of these systems. This must be done while retaining the best performance characteristics available today, a gross design point coefficient of performance (COP) of 1.3 and a net design (seasonal) average COP of 1.0 (0.90) in a directly fired, double effect unit. We have investigated several possible routes to these goals, and here report on these findings, focusing on the areas that appear most promising. The candidate technologies include the use of polymer film heat exchangers in several applications, the use of thin strips of new, corrosion resistant alloys to replace thicker, less impervious metals in applications exposed to gas flames, and copper or cupro-nickel foils in contact with system water. The use of such materials is only possible in the context of new heat exchanger and system designs, which are also discussed. To lend focus, we have concentrated on a directly fired double effect system providing capacity only. If successful, these techniques will also find wide applicability in heat pumps, cogeneration systems, solar cooling, heat recovery and chemical process heat transfer. 46 refs., 24 figs., 22 tabs.

  6. Absorption media for irreversibly gettering thionyl chloride

    DOE Patents [OSTI]

    Buffleben, George (Tracy, CA); Goods, Steven H. (Livermore, CA); Shepodd, Timothy (Livermore, CA); Wheeler, David R. (Albuquerque, NM); Whinnery, Jr., LeRoy (Danville, CA)

    2002-01-01

    Thionyl chloride is a hazardous and reactive chemical used as the liquid cathode in commercial primary batteries. Contrary to previous thinking, ASZM-TEDA.RTM. carbon (Calgon Corporation) reversibly absorbs thionyl chloride. Thus, several candidate materials were examined as irreversible getters for thionyl chloride. The capacity, rate and effect of temperature were also explored. A wide variety of likely materials were investigated through screening experiments focusing on the degree of heat generated by the reaction as well as the material absorption capacity and irreversibility, in order to help narrow the group of possible getter choices. More thorough, quantitative measurements were performed on promising materials. The best performing getter was a mixture of ZnO and ASZM-TEDA.RTM. carbon. In this example, the ZnO reacts with thionyl chloride to form ZnCl.sub.2 and SO.sub.2. The SO.sub.2 is then irreversibly gettered by ASZM-TEDA.RTM. carbon. This combination of ZnO and carbon has a high capacity, is irreversible and functions effectively above -20.degree. C.

  7. Permeation absorption sampler with multiple detection

    DOE Patents [OSTI]

    Zaromb, Solomon (Hinsdale, IL)

    1990-01-01

    A system for detecting analytes in air or aqueous systems includes a permeation absorption preconcentrator sampler for the analytes and analyte detectors. The preconcentrator has an inner fluid-permeable container into which a charge of analyte-sorbing liquid is intermittently injected, and a fluid-impermeable outer container. The sample is passed through the outer container and around the inner container for trapping and preconcentrating the analyte in the sorbing liquid. The analyte can be detected photometrically by injecting with the sorbing material a reagent which reacts with the analyte to produce a characteristic color or fluorescence which is detected by illuminating the contents of the inner container with a light source and measuring the absorbed or emitted light, or by producing a characteristic chemiluminescence which can be detected by a suitable light sensor. The analyte can also be detected amperometrically. Multiple inner containers may be provided into which a plurality of sorbing liquids are respectively introduced for simultaneously detecting different analytes. Baffles may be provided in the outer container. A calibration technique is disclosed.

  8. Triple effect absorption chiller utilizing two refrigeration circuits

    DOE Patents [OSTI]

    DeVault, Robert C. (Knoxville, TN)

    1988-01-01

    A triple effect absorption method and apparatus having a high coefficient of performance. Two single effect absorption circuits are combined with heat exchange occurring between a condenser and absorber of a high temperature circuit, and a generator of a low temperature circuit. The evaporators of both the high and low temperature circuits provide cooling to an external heat load.

  9. A technique for measuring winds in the lower atmosphere using incoherent Doppler lidar

    SciTech Connect (OSTI)

    DeSlover, D.H.; Slaughter, D.R.; Tulloch, W.M.; White, W.E.

    1993-04-14

    Wind speed is useful from a meteorological standpoint, in atmospheric modeling, and assessment of trace gas dispersal. A continuing effort is involved in improving the sensitivity of such measurements, and is exemplified by the literature. The Mobile Atmospheric Research Laboratory (MARL) at Lawrence Livermore National Laboratory (LLNL) is currently developing a method to improve the sensitivity of wind sounding in the lower through middle atmosphere using a pair of Fabry- Perot interferometers in parallel. This technique, first described by Chanin, et al., for the middle atmosphere using Doppler Rayleigh lidar, can be applied to the lower atmosphere where Mie (aerosol) backscatter is strong. Elastic events, inherent in both Rayleigh and Mie backscatter, dominate the return signal throughout the atmosphere. Both are susceptible to local wind vectors; which will Doppler shift the laser frequency proportional to the wind velocity. A pair of Fabry-Perot interferometers, tuned to either side of the laser frequency, will provide necessary data to determine the shift in frequency of the backscattered signal. Spectral drift and jitter of the laser and a lack of data points to determine the wind vector place limits on the sensitivity of the system. A method to minimize each of these is presented.

  10. A technique for measuring winds in the lower atmosphere using incoherent Doppler lidar

    SciTech Connect (OSTI)

    DeSlover, D.H.; Slaughter, D.R.; Tulloch, W.M.; White, W.E.

    1993-04-14

    Wind speed is useful from a meteorological standpoint, in atmospheric modeling, and assessment of trace gas dispersal. A continuing effort is involved in improving the sensitivity of such measurements, and is exemplified by the literature. The Mobile Atmospheric Research Laboratory (MARL) at Lawrence Livermore National Laboratory (LLNL) is currently developing a method to improve the sensitivity of wind sounding in the lower through middle atmosphere using a pair of Fabry-Perot interferometers in parallel. This technique, first described by Chanin, et al., for the middle atmosphere using Doppler Rayleigh lidar, can be applied to the lower atmosphere where Mie (aerosol) backscatter is strong. Elastic events, inherent in both Rayleigh and Mie backscatter, dominate the return signal throughout the atmosphere. Both are susceptible to local wind vectors; which will Doppler shift the laser frequency proportional to the wind velocity. A pair of Fabry-Perot interferometers, tuned to either side of the laser frequency, will provide necessary data to determine the shift in frequency of the backscattered signal. Spectral drift and jitter of the laser and a lack of data points to determine the wind vector place limits on the sensitivity of the system. A method to minimize each of these is presented.

  11. Estimations of atmospheric boundary layer fluxes and other turbulence parameters from Doppler lidar data

    SciTech Connect (OSTI)

    Tzvi Galchen; Mei Xu ); Eberhard, W.L. )

    1992-11-30

    This work is part of the First International Satellite Land Surface Climatology Project (ISLSCP) Field Experiment (FIFE), an international land-surface-atmosphere experiment aimed at improving the way climate models represent energy, water, heat, and carbon exchanges, and improving the utilization of satellite based remote sensing to monitor such parameters. Here the authors present results on doppler LIDAR measurements used to measure a range of turbulence parameters in the region of the unstable planetary boundary layer (PBL). The parameters include, averaged velocities, cartesian velocities, variances in velocities, parts of the covariance associated with vertical fluxes of horizontal momentum, and third moments of the vertical velocity. They explain their analysis technique, especially as it relates to error reduction of the averaged turbulence parameters from individual measurements with relatively large errors. The scales studied range from 150m to 12km. With this new diagnostic they address questions about the behavior of the convectively unstable PBL, as well as the stable layer which overlies it.

  12. Detection of preferential particle orientation in the atmosphere. Development of an alternative polarization lidar system

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Geier, Manfred; Arienti, Marco

    2014-07-19

    Increasing interest in polarimetric characterization of atmospheric aerosols has led to the development of complete sample-measuring (Mueller) polarimeters that are capable of measuring the entire backscattering phase matrix of a probed volume. The Mueller polarimeters consist of several moving parts, which limit measurement rates and complicate data analysis. In this paper, we present the concept of a less complex polarization lidar setup for detection of preferential orientation of atmospheric particulates. On the basis of theoretical considerations of data inversion stability and propagation of measurement uncertainties, an optimum optical configuration is established for two modes of operation (with either a linearmore » or a circular polarized incident laser beam). We discovered that the conceptualized setup falls in the category of incomplete sample-measuring polarimeters and uses four detection channels for simultaneous measurement of the backscattered light. Likewise, the expected performance characteristics are discussed through an example of a typical aerosol with a small fraction of particles oriented in a preferred direction. As a result, the theoretical analysis suggests that achievable accuracies in backscatter cross-sections and depolarization ratios are similar to those with conventional two-channel configurations, while in addition preferential orientation can be detected with the proposed four-channel system for a wide range of conditions.« less

  13. Detection of preferential particle orientation in the atmosphere. Development of an alternative polarization lidar system

    SciTech Connect (OSTI)

    Geier, Manfred; Arienti, Marco

    2014-07-19

    Increasing interest in polarimetric characterization of atmospheric aerosols has led to the development of complete sample-measuring (Mueller) polarimeters that are capable of measuring the entire backscattering phase matrix of a probed volume. The Mueller polarimeters consist of several moving parts, which limit measurement rates and complicate data analysis. In this paper, we present the concept of a less complex polarization lidar setup for detection of preferential orientation of atmospheric particulates. On the basis of theoretical considerations of data inversion stability and propagation of measurement uncertainties, an optimum optical configuration is established for two modes of operation (with either a linear or a circular polarized incident laser beam). We discovered that the conceptualized setup falls in the category of incomplete sample-measuring polarimeters and uses four detection channels for simultaneous measurement of the backscattered light. Likewise, the expected performance characteristics are discussed through an example of a typical aerosol with a small fraction of particles oriented in a preferred direction. As a result, the theoretical analysis suggests that achievable accuracies in backscatter cross-sections and depolarization ratios are similar to those with conventional two-channel configurations, while in addition preferential orientation can be detected with the proposed four-channel system for a wide range of conditions.

  14. Nocturnal Low-Level-Jet-Dominated Atmospheric Boundary Layer Observed by a Doppler Lidar Over Oklahoma City during JU2003

    SciTech Connect (OSTI)

    Wang, Yansen; Klipp, Cheryl L.; Garvey, Dennis M.; Ligon, David; Williamson, Chatt C.; Chang, Sam S.; Newsom, Rob K.; Calhoun, Ron

    2007-12-01

    Boundary layer wind data observed by a Doppler lidar and sonic anemometers during the mornings of three intensive observational periods (IOP2, IOP3, and IOP7) of the Joint Urban 2003 (JU2003) field experiment are analyzed to extract the mean and turbulent characteristics of airflow over Oklahoma City, Oklahoma. A strong nocturnal low-level jet (LLJ) dominated the flow in the boundary layer over the measurement domain from midnight to the morning hours. Lidar scans through the LLJ taken after sunrise indicate that the LLJ elevation shows a gradual increase of 25-100 m over the urban area relative to that over the upstream suburban area. The mean wind speed beneath the jet over the urban area is about 10%-15% slower than that over the suburban area. Sonic anemometer observations combined with Doppler lidar observations in the urban and suburban areas are also analyzed to investigate the boundary layer turbulence production in the LLJ-dominated atmospheric boundary layer. The turbulence kinetic energy was higher over the urban domain mainly because of the shear production of building surfaces and building wakes. Direct transport of turbulent momentum flux from the LLJ to the urban street level was very small because of the relatively high elevation of the jet. However, since the LLJ dominated the mean wind in the boundary layer, the turbulence kinetic energy in the urban domain is correlated directly with the LLJ maximum speed and inversely with its height. The results indicate that the jet Richardson number is a reasonably good indicator for turbulent kinetic energy over the urban domain in the LLJ-dominated atmospheric boundary layer.

  15. A digital map of the high center (HC) and low center (LC) polygon boundaries delineated from high resolution LiDAR data for Barrow, Alaska

    SciTech Connect (OSTI)

    Gangodagamage, Chandana; Wullschleger, Stan

    2014-07-03

    This dataset represent a map of the high center (HC) and low center (LC) polygon boundaries delineated from high resolution LiDAR data for the arctic coastal plain at Barrow, Alaska. The polygon troughs are considered as the surface expression of the ice-wedges. The troughs are in lower elevations than the interior polygon. The trough widths were initially identified from LiDAR data, and the boundary between two polygons assumed to be located along the lowest elevations on trough widths between them.

  16. Molecular shock response of explosives: electronic absorption spectroscopy

    SciTech Connect (OSTI)

    Mcgrne, Shawn D; Moore, David S; Whitley, Von H; Bolme, Cindy A; Eakins, Daniel E

    2009-01-01

    Electronic absorption spectroscopy in the range 400-800 nm was coupled to ultrafast laser generated shocks to begin addressing the question of the extent to which electronic excitations are involved in shock induced reactions. Data are presented on shocked polymethylmethacrylate (PMMA) thin films and single crystal pentaerythritol tetranitrate (PETN). Shocked PMMA exhibited thin film interference effects from the shock front. Shocked PETN exhibited interference from the shock front as well as broadband increased absorption. Relation to shock initiation hypotheses and the need for time dependent absorption data (future experiments) is briefly discussed.

  17. Commercial Absorption Heat Pump Water Heater | Department of Energy

    Office of Environmental Management (EM)

    Commercial Absorption Heat Pump Water Heater Commercial Absorption Heat Pump Water Heater Lead Performer: Oak Ridge National Laboratory - Oak Ridge, TN Partner: A.O. Smith, Inc. - Milwaukee, WI DOE Funding: $2,000,000 Cost Share: Provided by CRADA partners Project Term: 10/1/2013 - 9/30/2016 Project Objective The objective of this project is to develop a gas-fired absorption heat pump water heater for the commercial market, capable of an energy factor greater than 1.0 as determined by the

  18. Calculation of aerosol backscatter from airborne continuous wave focused CO sub 2 Doppler lidar measurements. 1. Algorithm description

    SciTech Connect (OSTI)

    Rothermel, J. ); Bowdle, D.A. ); Vaughan, J.M.; Brown, D.W. ); Woodfield, A.A. )

    1991-03-20

    Since 1981 the Royal Signals and Radar Establishment and the Royal Aircraft Establishment, United Kingdom, have made vertical and horizontal sounding measurements of aerosol backscatter coefficients at 10.6 {mu}m using an airborne continuous wave focused CO{sub 2} Doppler lidar, the Laser True Airspeed System (LATAS). The heterodyne signal from the LATAS detector is spectrally analyzed. Then, in conjunction with aircraft flight parameters, the data are processed in a six-stage computer algorithm: Set search window, search for peak signal, test peak signal, measure total signal, calculate signal-to-noise ratio (SNR), and calculate backscatter coefficient.

  19. Estimation of the mixing layer height over a high altitude site in Central Himalayan region by using Doppler lidar

    SciTech Connect (OSTI)

    Shukla, K. K.; Phanikumar, D. V.; Newsom, Rob K.; Kumar, Niranjan; Ratnam, Venkat; Naja, M.; Singh, Narendra

    2014-03-01

    A Doppler lidar was installed at Manora Peak, Nainital (29.4 N; 79.2 E, 1958 amsl) to estimate mixing layer height for the first time by using vertical velocity variance as basic measurement parameter for the period September-November 2011. Mixing layer height is found to be located ~0.57 +/- 0.1and 0.45 +/- 0.05km AGL during day and nighttime, respectively. The estimation of mixing layer height shows good correlation (R>0.8) between different instruments and with different methods. Our results show that wavelet co-variance transform is a robust method for mixing layer height estimation.

  20. Overview of Resources for Geothermal Absorption Cooling for Buildings

    SciTech Connect (OSTI)

    Liu, Xiaobing; Gluesenkamp, Kyle R; Mehdizadeh Momen, Ayyoub

    2015-06-01

    This report summarizes the results of a literature review in three areas: available low-temperature/coproduced geothermal resources in the United States, energy use for space conditioning in commercial buildings, and state of the art of geothermal absorption cooling.

  1. Use Low-Grade Waste Steam to Power Absorption Chillers

    SciTech Connect (OSTI)

    Not Available

    2006-01-01

    This revised ITP tip sheet on waste steam to power absorption chillers provides how-to advice for improving the system using low-cost, proven practices and technologies.

  2. pressure-swing-absorption-njit | netl.doe.gov

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Pressure Swing Absorption Device and Process for Separating CO2 from Shifted Syngas and its Capture for Subsequent Storage Project No.: DE-FE0001323 New Jersey Institute of...

  3. ARM - Instrument - psap-particle-soot-absorption-photometer

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    govInstrumentspsap-particle-soot-absorption-photometer Documentation Comments? We would love to hear from you Send us a note below or call us at 1-888-ARM-DATA. Send Instrument :...

  4. Collision--induced absorption in dense atmospheres of cool stars

    SciTech Connect (OSTI)

    Borysow, Aleksandra; Joergensen, Uffe Graae

    1999-04-01

    In the atmosphere of the Sun the major interaction between the matter and the radiation is through light absorption by ions (predominantly the negative ion of hydrogen atoms), neutral atoms and a small amount of polar molecules. The majority of stars in the universe are, however, cooler and denser than our Sun, and for a large fraction of these, the above absorption processes are very weak. Here, collision-induced absorption (CIA) becomes the dominant opacity source. The radiation is absorbed during very short mutual passages ('collisions') of two non-polar molecules (and/or atoms), while their electric charge distributions are temporarily distorted which gives rise to a transient dipole moment. We present here a review of the present-day knowledge about the impact of collision-induced absorption processes on the structure and the spectrum of such stars.

  5. Light Trapping, Absorption and Solar Energy Harvesting by Artificial

    Office of Scientific and Technical Information (OSTI)

    Materials (Technical Report) | SciTech Connect Technical Report: Light Trapping, Absorption and Solar Energy Harvesting by Artificial Materials Citation Details In-Document Search Title: Light Trapping, Absorption and Solar Energy Harvesting by Artificial Materials We provide designs of thin-film solar cells utilizing optimized photonic-crystal light-trapping and numerical simulations of their solar-to-electrical power conversion efficiencies. Authors: John, Sajeev [1] + Show Author

  6. Measuring fast electron spectra and laser absorption in relativistic

    Office of Scientific and Technical Information (OSTI)

    laser-solid interactions using differential bremsstrahlung photon detectors (Journal Article) | SciTech Connect Measuring fast electron spectra and laser absorption in relativistic laser-solid interactions using differential bremsstrahlung photon detectors Citation Details In-Document Search Title: Measuring fast electron spectra and laser absorption in relativistic laser-solid interactions using differential bremsstrahlung photon detectors Authors: Scott, RHH ; Clark, EL ; Perez, F ;

  7. Flexible flux plane simulations of parasitic absorption in nanoplasmonic

    Office of Scientific and Technical Information (OSTI)

    thin-film silicon solar cells (Journal Article) | DOE PAGES Flexible flux plane simulations of parasitic absorption in nanoplasmonic thin-film silicon solar cells « Prev Next » Title: Flexible flux plane simulations of parasitic absorption in nanoplasmonic thin-film silicon solar cells Authors: Chung, H. ; Jung, K-Y ; Bermel, P. Publication Date: 2015-08-31 OSTI Identifier: 1222228 Grant/Contract Number: EE0004946 Type: Published Article Journal Name: Optical Materials Express Additional

  8. Advanced Low Temperature Absorption Chiller Module Integrated with a CHP

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    System at a Distributed Data Center - Presentation by Exergy Partners Corp., June 2011 | Department of Energy Low Temperature Absorption Chiller Module Integrated with a CHP System at a Distributed Data Center - Presentation by Exergy Partners Corp., June 2011 Advanced Low Temperature Absorption Chiller Module Integrated with a CHP System at a Distributed Data Center - Presentation by Exergy Partners Corp., June 2011 Presentation on Develop & Demonstrate an Advanced Low Temp Heat

  9. Energy Saving Absorption Heat Pump Water Heater - Energy Innovation Portal

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Building Energy Efficiency Building Energy Efficiency Find More Like This Return to Search Energy Saving Absorption Heat Pump Water Heater Oak Ridge National Laboratory Contact ORNL About This Technology Technology Marketing SummaryORNL's new absorption heat pump and water heater technology offers substantial energy savings and can reduce the use of fossil fuels by buildings. While conventional heat pump water heater designs are limited to using toxic ammonia water systems, this system uses heat

  10. Combining Feedback Absorption Spectroscopy, Amplified Resonance and Low

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Pressure Sampling for the Measurement of Nitrogen-Containing Compounds in Automotive Emissions | Department of Energy Feedback Absorption Spectroscopy, Amplified Resonance and Low Pressure Sampling for the Measurement of Nitrogen-Containing Compounds in Automotive Emissions Combining Feedback Absorption Spectroscopy, Amplified Resonance and Low Pressure Sampling for the Measurement of Nitrogen-Containing Compounds in Automotive Emissions Discusses a novel combination of multi-component

  11. Mechanical properties and energy absorption characteristics of a

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    polyurethane foam (Technical Report) | SciTech Connect Mechanical properties and energy absorption characteristics of a polyurethane foam Citation Details In-Document Search Title: Mechanical properties and energy absorption characteristics of a polyurethane foam × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of DOE's Office of Scientific and Technical Information (OSTI) and is provided as a public service. Visit OSTI to utilize

  12. X-ray transient absorption and picosecond IR spectroscopy of

    Office of Scientific and Technical Information (OSTI)

    fulvalene(tetracarbonyl)diruthenium on photoexcitation (Journal Article) | SciTech Connect X-ray transient absorption and picosecond IR spectroscopy of fulvalene(tetracarbonyl)diruthenium on photoexcitation Citation Details In-Document Search Title: X-ray transient absorption and picosecond IR spectroscopy of fulvalene(tetracarbonyl)diruthenium on photoexcitation Authors: Harpham, M. R. ; Nguyen, S. C. ; Hou, Z. ; Grossman, J. C. ; Harris, C. B. ; Mara, M. W. ; Stickrath, A. B. ; Kanai, Y. ;

  13. Modelling aging effects on a thermal cycling absorption process column

    SciTech Connect (OSTI)

    Laquerbe, C.; Contreras, S.; Demoment, J.

    2008-07-15

    Palladium coated on alumina is used in hydrogen separation systems operated at CEA/Valduc, and more particularly in Thermal Cycling Absorption Process columns. With such materials, tritium decay is known to induce aging effects which have direct side effects on hydrogen isotopes absorption isotherms. Furthermore in a TCAP column, aging occurs in an heterogeneous way. The possible impacts of these intrinsic material evolutions on the separation performances are investigated here through a numerical approach. (authors)

  14. Near-infrared free carrier absorption in heavily doped silicon

    SciTech Connect (OSTI)

    Baker-Finch, Simeon C.; McIntosh, Keith R.; Yan, Di; Fong, Kean Chern; Kho, Teng C.

    2014-08-14

    Free carrier absorption in heavily doped silicon can have a significant impact on devices operating in the infrared. In the near infrared, the free carrier absorption process can compete with band to band absorption processes, thereby reducing the number of available photons to optoelectronic devices such as solar cells. In this work, we fabricate 18 heavily doped regions by phosphorus and boron diffusion into planar polished silicon wafers; the simple sample structure facilitates accurate and precise measurement of the free carrier absorptance. We measure and model reflectance and transmittance dispersion to arrive at a parameterisation for the free carrier absorption coefficient that applies in the wavelength range between 1000 and 1500 nm, and the range of dopant densities between ∼10{sup 18} and 3 × 10{sup 20} cm{sup −3}. Our measurements indicate that previously published parameterisations underestimate the free carrier absorptance in phosphorus diffusions. On the other hand, published parameterisations are generally consistent with our measurements and model for boron diffusions. Our new model is the first to be assigned uncertainty and is well-suited to routine device analysis.

  15. Quasi-static energy absorption of hollow microlattice structures

    SciTech Connect (OSTI)

    Liu, YL; Schaedler, TA; Jacobsen, AJ; Chen, X

    2014-12-01

    We present a comprehensive modeling and numerical study focusing on the energy quasi-static crushing behavior and energy absorption characteristics of hollow tube microlattice structures. The peak stress and effective plateau stress of the hollow microlattice structures are deduced for different geometrical parameters which gives volume and mass densities of energy absorption, D-v and D-m, scale with the relative density, (rho) over bar, as D-v similar to (rho) over bar (1) (5) and D-m similar to (rho) over bar (0 5), respectively, fitting very well to the experimental results of both 60 degrees inclined and 90 degrees predominately microlattices. Then the strategies for energy absorption enhancement are proposed for the engineering design of microlattice structures. By introducing a gradient in the thickness or radius of the lattice members, the buckle propagation can be modulated resulting in an increase in energy absorption density that can exceed 40%. Liquid filler is another approach to improve energy absorption by strengthening the microtruss via circumference expansion, and the gain may be over 100% in terms of volume density. Insight into the correlations between microlattice architecture and energy absorption performance combined with the high degree of architecture control paves the way for designing high performance microlattice structures for a range of impact and impulse mitigation applications for vehicles and structures. (C) 2014 Elsevier Ltd. All rights reserved.

  16. Wind flow in the Fraser Valley as measured by a pulsed CO{sub 2} Doppler lidar

    SciTech Connect (OSTI)

    Olivier, L.D.; Banta, R.M.; Hardesty, R.M.

    1994-12-31

    The Vancouver, British Columbia metropolitan area, with a population close to 1.5 million people, experiences high levels of tropospheric ozone during the summer months. The transport of pollution, including tropospheric ozone, in the Vancouver area, is influenced by a local land/sea breeze circulation, the valley flows associated with the Lower Fraser River Valley to the east of the city, and the complex terrain to the north and northeast of the city. In July and August of 1993, an experiment was conducted in the Vancouver area to assess the distribution and transport of tropospheric ozone. Wind flow and aerosol measurements were obtained with a pulsed CO(sub 2) Doppler lidar and wind fields and their interactions with the complex terrain were mapped. The combination of Doppler lidar measurements of wind velocity and backscattered signal intensity, obtained simultaneously, will help identify wind flow patterns that enhanced the transport of urban pollution from the city of Vancouver to the Lower Fraser River Valley, and the possible recirculation of these pollutants back into Vancouver.

  17. Horizontal-Velocity and Variance Measurements in the Stable Boundary Layer Using Doppler Lidar: Sensitivity to Averaging Procedures

    SciTech Connect (OSTI)

    Pichugina, Yelena L.; Banta, Robert M.; Kelley, Neil D.; Jonkman, Bonnie J.; Tucker, Sara C.; Newsom, Rob K.; Brewer, W. A.

    2008-08-01

    Quantitative data on turbulence variables aloft--above the region of the atmosphere conveniently measured from towers--has been an important but difficult measurement need for advancing understanding and modeling of the stable boundary layer (SBL). Vertical profiles of streamwise velocity variances obtained from NOAAs High Resolution Doppler Lidar (HRDL), which have been shown to be numerically equivalent to turbulence kinetic energy (TKE) for stable conditions, are a measure of the turbulence in the SBL. In the present study, the mean horizontal wind component U and variance ?u2 were computed from HRDL measurements of the line-of-sight (LOS) velocity using a technique described in Banta, et al. (2002). The technique was tested on datasets obtained during the Lamar Low-Level Jet Project (LLLJP) carried out in early September 2003, near the town of Lamar in southeastern Colorado. This paper compares U with mean wind speed obtained from sodar and sonic anemometer measurements. It then describes several series of averaging tests that produced the best correlation between TKE calculated from sonic anemometer data at several tower levels and lidar measurements of horizontal velocity variance ?u2. The results show high correlation (0.71-0.97) of the mean U and average wind speed measured by sodar and in-situ instruments, independent of sampling strategies and averaging procedures. Comparison of estimates of variance, on the other hand, proved sensitive to both the spatial and temporal averaging techniques.

  18. Carbon Dioxide Separation from Flue Gas by Phase Enhanced Absorption

    SciTech Connect (OSTI)

    Tim Fout

    2007-06-30

    A new process, phase enhanced absorption, was invented. The method is carried out in an absorber, where a liquid carrier (aqueous solution), an organic mixture (or organic compound), and a gas mixture containing a gas to be absorbed are introduced from an inlet. Since the organic mixture is immiscible or at least partially immiscible with the liquid carrier, the organic mixture forms a layer or small parcels between the liquid carrier and the gas mixture. The organic mixture in the absorber improves mass transfer efficiency of the system and increases the absorption rate of the gas. The organic mixture serves as a transportation media. The gas is finally accumulated in the liquid carrier as in a conventional gas-liquid absorption system. The presence of the organic layer does not hinder the regeneration of the liquid carrier or recovery of the gas because the organic layer is removed by a settler after the absorption process is completed. In another aspect, the system exhibited increased gas-liquid separation efficiency, thereby reducing the costs of operation and maintenance. Our study focused on the search of the organic layer or transportation layer to enhance the absorption rate of carbon dioxide. The following systems were studied, (1) CO{sub 2}-water system and CO{sub 2}-water-organic layer system; (2) CO{sub 2}-Potassium Carbonate aqueous solution system and CO{sub 2}-Potassium Carbonate aqueous solution-organic layer system. CO{sub 2}-water and CO{sub 2}-Potassium Carbonate systems are the traditional gas-liquid absorption processes. The CO{sub 2}-water-organic layer and CO{sub 2}-Potassium Carbonate-organic layer systems are the novel absorption processes, phase enhanced absorption. As we mentioned early, organic layer is used for the increase of absorption rate, and plays the role of transportation of CO{sub 2}. Our study showed that the absorption rate can be increased by adding the organic layer. However, the enhanced factor is highly depended on the liquid mass transfer coefficients for the CO{sub 2}-water-organic layer system. For the CO{sub 2}-Potassium Carbonate aqueous solution-organic layer system, the enhanced factor is not only dependent on the liquid mass transfer coefficients, but also the chemical reaction rates.

  19. The probability of laser caused ocular injury to the aircrew of undetected aircraft violating the exclusion zone about the airborne aura LIDAR.

    SciTech Connect (OSTI)

    Augustoni, Arnold L.

    2006-12-01

    The probability of a laser caused ocular injury, to the aircrew of an undetected aircraft entering the exclusion zone about the AURA LIDAR airborne platform with the possible violation of the Laser Hazard Zone boundary, was investigated and quantified for risk analysis and management.

  20. LIDAR Wind Speed Measurement Analysis and Feed-Forward Blade Pitch Control for Load Mitigation in Wind Turbines: January 2010--January 2011

    SciTech Connect (OSTI)

    Dunne, F.; Simley, E.; Pao, L.Y.

    2011-10-01

    This report examines the accuracy of measurements that rely on Doppler LIDAR systems to determine their applicability to wind turbine feed-forward control systems and discusses feed-forward control system designs that use preview wind measurements. Light Detection and Ranging (LIDAR) systems are able to measure the speed of incoming wind before it interacts with a wind turbine rotor. These preview wind measurements can be used in feed-forward control systems designed to reduce turbine loads. However, the degree to which such preview-based control techniques can reduce loads by reacting to turbulence depends on how accurately the incoming wind field can be measured. The first half of this report examines the accuracy of different measurement scenarios that rely on coherent continuous-wave or pulsed Doppler LIDAR systems to determine their applicability to feed-forward control. In particular, the impacts of measurement range and angular offset from the wind direction are studied for various wind conditions. A realistic case involving a scanning LIDAR unit mounted in the spinner of a wind turbine is studied in depth with emphasis on choices for scan radius and preview distance. The effects of turbulence parameters on measurement accuracy are studied as well. Continuous-wave and pulsed LIDAR models based on typical commercially available units were used in the studies present in this report. The second half of this report discusses feed-forward control system designs that use preview wind measurements. Combined feedback/feed-forward blade pitch control is compared to industry standard feedback control when simulated in realistic turbulent above-rated winds. The feed-forward controllers are designed to reduce fatigue loads, increasing turbine lifetime and therefore reducing the cost of energy. Three feed-forward designs are studied: non-causal series expansion, Preview Control, and optimized FIR filter. The input to the feed-forward controller is a measurement of incoming wind speeds that could be provided by LIDAR. Non-causal series expansion and Preview Control methods reduce blade root loads but increase tower bending in simulation results. The optimized FIR filter reduces loads overall, keeps pitch rates low, and maintains rotor speed regulation and power capture, while using imperfect wind measurements provided by the spinning continuous-wave LIDAR model.

  1. Development of an Ionic-Liquid Absorption Heat Pump

    SciTech Connect (OSTI)

    Holcomb, Don

    2011-03-29

    Solar Fueled Products (SFP) is developing an innovative ionic-liquid absorption heat pump (ILAHP). The development of an ILAHP is extremely significant, as it could result in annual savings of more than 190 billion kW h of electrical energy and $19 billion. This absorption cooler uses about 75 percent less electricity than conventional cooling and heating units. The ILAHP also has significant environmental sustainability benefits, due to reduced CO2 emissions. Phase I established the feasibility and showed the economic viability of an ILAHP with these key accomplishments: Used the breakthrough capabilities provided by ionic liquids which overcome the key difficulties of the common absorption coolers. Showed that the theoretical thermodynamic performance of an ILAHP is similar to existing absorption-cooling systems. Established that the half-effect absorption cycle reduces the peak generator temperature, improving collector efficiency and reducing collector area. Component testing demonstrated that the most critical components, absorber and generator, operate well with conventional heat exchangers. Showed the economic viability of an ILAHP. The significant energy savings, sustainability benefits, and economic viability are compelling reasons to continue the ILAHP development.

  2. Method and apparatus for aerosol particle absorption spectroscopy

    DOE Patents [OSTI]

    Campillo, Anthony J.; Lin, Horn-Bond

    1983-11-15

    A method and apparatus for determining the absorption spectra, and other properties, of aerosol particles. A heating beam source provides a beam of electromagnetic energy which is scanned through the region of the spectrum which is of interest. Particles exposed to the heating beam which have absorption bands within the band width of the heating beam absorb energy from the beam. The particles are also illuminated by light of a wave length such that the light is scattered by the particles. The absorption spectra of the particles can thus be determined from an analysis of the scattered light since the absorption of energy by the particles will affect the way the light is scattered. Preferably the heating beam is modulated to simplify the analysis of the scattered light. In one embodiment the heating beam is intensity modulated so that the scattered light will also be intensity modulated when the particles absorb energy. In another embodiment the heating beam passes through an interferometer and the scattered light reflects the Fourier Transform of the absorption spectra.

  3. Tunable enhanced optical absorption of graphene using plasmonic perfect absorbers

    SciTech Connect (OSTI)

    Cai, Yijun; Zhu, Jinfeng; Liu, Qing Huo

    2015-01-26

    Enhancement and manipulation of light absorption in graphene is a significant issue for applications of graphene-based optoelectronic devices. In order to achieve this purpose in the visible region, we demonstrate a design of a graphene optical absorber inspired by metal-dielectric-metal metamaterial for perfect absorption of electromagnetic waves. The optical absorbance ratios of single and three atomic layer graphene are enhanced up to 37.5% and 64.8%, respectively. The graphene absorber shows polarization-dependence and tolerates a wide range of incident angles. Furthermore, the peak position and bandwidth of graphene absorption spectra are tunable in a wide wavelength range through a specific structural configuration. These results imply that graphene in combination with plasmonic perfect absorbers have a promising potential for developing advanced nanophotonic devices.

  4. Backscatter absorption gas imaging systems and light sources therefore

    DOE Patents [OSTI]

    Kulp, Thomas Jan (Livermore, CA); Kliner, Dahv A. V. (San Ramon, CA); Sommers, Ricky (Oakley, CA); Goers, Uta-Barbara (Campbell, NY); Armstrong, Karla M. (Livermore, CA)

    2006-12-19

    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 imaging (BAGI) system, and a light source incorporating the light source, that can be used to remotely detect and produce images of "invisible" gases. The inventive light source has a light producing element, an optical amplifier, and an optical parametric oscillator to generate wavelength tunable light in the IR. By using a multi-mode light source and an amplifier that operates using 915 nm pump sources, the power consumption of the light source is reduced to a level that can be operated by batteries for long periods of time. In addition, the light source is tunable over the absorption bands of many hydrocarbons, making it useful for detecting hazardous gases.

  5. Direct and quantitative broadband absorptance spectroscopy with multilayer cantilever probes

    DOE Patents [OSTI]

    Hsu, Wei-Chun; Tong, Jonathan Kien-Kwok; Liao, Bolin; Chen, Gang

    2015-04-21

    A system for measuring the absorption spectrum of a sample is provided that includes a broadband light source that produces broadband light defined within a range of an absorptance spectrum. An interferometer modulates the intensity of the broadband light source for a range of modulation frequencies. A bi-layer cantilever probe arm is thermally connected to a sample arm having at most two layers of materials. The broadband light modulated by the interferometer is directed towards the sample and absorbed by the sample and converted into heat, which causes a temperature rise and bending of the bi-layer cantilever probe arm. A detector mechanism measures and records the deflection of the probe arm so as to obtain the absorptance spectrum of the sample.

  6. Piezoelectric-tuned microwave cavity for absorption spectrometry

    DOE Patents [OSTI]

    Leskovar, Branko; Buscher, Harold T.; Kolbe, William F.

    1978-01-01

    Gas samples are analyzed for pollutants in a microwave cavity that is provided with two highly polished walls. One wall of the cavity is mechanically driven with a piezoelectric transducer at a low frequency to tune the cavity over a band of microwave frequencies in synchronism with frequency modulated microwave energy applied to the cavity. Absorption of microwave energy over the tuned frequencies is detected, and energy absorption at a particular microwave frequency is an indication of a particular pollutant in the gas sample.

  7. High resolution absorption spectroscopy of exploding wire plasmas using an

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    x-pinch x-ray source and spherically bent crystal (Journal Article) | DOE PAGES High resolution absorption spectroscopy of exploding wire plasmas using an x-pinch x-ray source and spherically bent crystal Title: High resolution absorption spectroscopy of exploding wire plasmas using an x-pinch x-ray source and spherically bent crystal Authors: Knapp, P. F. [1] ; Pikuz, S. A. [1] ; Shelkovenko, T. A. [1] ; Hammer, D. A. [1] ; Hansen, S. B. [2] + Show Author Affiliations Laboratory of Plasma

  8. Origins of optical absorption characteristics of Cu2+ complexes in

    Office of Scientific and Technical Information (OSTI)

    solutions (Journal Article) | SciTech Connect Origins of optical absorption characteristics of Cu2+ complexes in solutions Citation Details In-Document Search Title: Origins of optical absorption characteristics of Cu2+ complexes in solutions Authors: Qiu, S R ; Wood, B C ; Ehrmann, P R ; Demos, S G ; Miller, P E ; Schaffers, K I ; Suratwala, T I Publication Date: 2015-02-27 OSTI Identifier: 1234585 Report Number(s): LLNL-JRNL-668007 DOE Contract Number: AC52-07NA27344 Resource Type: Journal

  9. WATER-LITHIUM BROMIDE DOUBLE-EFFECT ABSORPTION COOLING ANALYSIS

    Office of Scientific and Technical Information (OSTI)

    WATER-LITHIUM BROMIDE DOUBLE-EFFECT ABSORPTION COOLING ANALYSIS Gary C . V l i e t , Michael B . Lawson, and Rudolf0 A . Lithgow Center f o r Energy Studies The University of Texas a t Austin December 1980 Final Report f o r Contract: DE AC03-79SF10540 (Mu1 tiple-Effect Absorption Cycle Solar Cooling) with the U.S. Department of Energy DISCLAIMER This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any

  10. High resolution absorption spectroscopy of exploding wire plasmas using an

    Office of Scientific and Technical Information (OSTI)

    x-pinch x-ray source and spherically bent crystal (Journal Article) | DOE PAGES Published Article: High resolution absorption spectroscopy of exploding wire plasmas using an x-pinch x-ray source and spherically bent crystal Title: High resolution absorption spectroscopy of exploding wire plasmas using an x-pinch x-ray source and spherically bent crystal Authors: Knapp, P. F. [1] ; Pikuz, S. A. [1] ; Shelkovenko, T. A. [1] ; Hammer, D. A. [1] ; Hansen, S. B. [2] + Show Author Affiliations

  11. Absorptive separation of NO from dilute off-gas

    SciTech Connect (OSTI)

    Zapfel, W.; Marr, R.; Siebenhofer, M.

    1999-04-01

    With regard to its negligible absorption properties, the separation of nitrogen monoxide from dilute off-gas is limited to bench-scale experiments. Investigation has been centered on improving the rate of absorption by the use of complex-forming additives based on iron(II) compounds. Further efforts have been made to improve the separation efficiency by the use of reactive additives. Due to the low reactivity of nitrogen monoxide, these attempts did not succeed. The oxidation of moderately concentrated off-gas with ozone and the absorption of the so-formed nitrogen dioxide have been reported. Technical as well as economical considerations do not permit the application of the process to the treatment of dilute off-gas. The principle underlying this process led to the investigation of direct oxidation of the off-gas under electrical discharge followed by absorption with aqueous diamide solution. Temperature and moisture of the off-gas have been considered, in addition to various feed contents of nitrogen monoxide. The results of this investigation show that direct oxidation of nitrogen monoxide by corona discharge is possible. The rate of conversion increases with increasing gas velocity, accompanied by a decreasing specific energy consumption. Applied to tunnel off-gas purification, the direct oxidation route seems to offer promising technical boundaries as it is accompanied by efficient particle separation.

  12. Methods for deacidizing gaseous mixtures by phase enhanced absorption

    DOE Patents [OSTI]

    Hu, Liang

    2012-11-27

    An improved process for deacidizing a gaseous mixture using phase enhanced gas-liquid absorption is described. The process utilizes a multiphasic absorbent that absorbs an acid gas at increased rate and leads to reduced overall energy costs for the deacidizing operation.

  13. Environmental monitoring: civilian applications of remote sensing

    SciTech Connect (OSTI)

    Bolton, W.; Lapp, M.; Vitko, J. Jr.; Phipps, G.

    1996-11-01

    This report documents the results of a Laboratory Directed Research and Development (LDRD) program to explore how best to utilize Sandia`s defense-related sensing expertise to meet the Department of Energy`s (DOE) ever-growing needs for environmental monitoring. In particular, we focused on two pressing DOE environmental needs: (1) reducing the uncertainties in global warming predictions, and (2) characterizing atmospheric effluents from a variety of sources. During the course of the study we formulated a concept for using unmanned aerospace vehicles (UAVs) for making key 0798 climate measurements; designed a highly accurate, compact, cloud radiometer to be flown on those UAVs; and established the feasibility of differential absorption Lidar (DIAL) to measure atmospheric effluents from waste sites, manufacturing processes, and potential treaty violations. These concepts have had major impact since first being formulated in this ,study. The DOE has adopted, and DoD`s Strategic Environmental Research Program has funded, much of the UAV work. And the ultraviolet DIAL techniques have already fed into a major DOE non- proliferation program.

  14. Monitoring PVD metal vapors using laser absorption spectroscopy

    SciTech Connect (OSTI)

    Braun, D.G.; Anklam, T.M.; Berzins, L.V.; Hagans, K.G.

    1994-04-01

    Laser absorption spectroscopy (LAS) has been used by the Atomic Vapor Laser Isotope Separation (AVLIS) program for over 10 years to monitor the co-vaporization of uranium and iron in its separators. During that time, LAS has proven to be an accurate and reliable method to monitor both the density and composition of the vapor. It has distinct advantages over other rate monitors, in that it is completely non-obtrusive to the vaporization process and its accuracy is unaffected by the duration of the run. Additionally, the LAS diagnostic has been incorporated into a very successful process control system. LAS requires only a line of sight through the vacuum chamber, as all hardware is external to the vessel. The laser is swept in frequency through an absorption line of interest. In the process a baseline is established, and the line integrated density is determined from the absorption profile. The measurement requires no hardware calibration. Through a proper choice of the atomic transition, a wide range of elements and densities have been monitored (e.g. nickel, iron, cerium and gadolinium). A great deal of information about the vapor plume can be obtained from the measured absorption profiles. By monitoring different species at the same location, the composition of the vapor is measured in real time. By measuring the same density at different locations, the spatial profile of the vapor plume is determined. The shape of the absorption profile is used to obtain the flow speed of the vapor. Finally, all of the above information is used evaluate the total vaporization rate.

  15. Temperature activated absorption during laser-induced damage: The evolution of laser-supported solid-state absorption fronts

    SciTech Connect (OSTI)

    Carr, C W; Bude, J D; Shen, N; Demange, P

    2010-10-26

    Previously we have shown that the size of laser induced damage sites in both KDP and SiO{sub 2} is largely governed by the duration of the laser pulse which creates them. Here we present a model based on experiment and simulation that accounts for this behavior. Specifically, we show that solid-state laser-supported absorption fronts are generated during a damage event and that these fronts propagate at constant velocities for laser intensities up to 4 GW/cm{sup 2}. It is the constant absorption front velocity that leads to the dependence of laser damage site size on pulse duration. We show that these absorption fronts are driven principally by the temperature-activated deep sub band-gap optical absorptivity, free electron transport, and thermal diffusion in defect-free silica for temperatures up to 15,000K and pressures < 15GPa. In addition to the practical application of selecting an optimal laser for pre-initiation of large aperture optics, this work serves as a platform for understanding general laser-matter interactions in dielectrics under a variety of conditions.

  16. Oil and gas exploration system and method for detecting trace amounts of hydrocarbon gases in the atmosphere

    DOE Patents [OSTI]

    Wamsley, Paula R. (Littleton, CO); Weimer, Carl S. (Littleton, CO); Nelson, Loren D. (Evergreen, CO); O'Brien, Martin J. (Pine, CO)

    2003-01-01

    An oil and gas exploration system and method for land and airborne operations, the system and method used for locating subsurface hydrocarbon deposits based upon a remote detection of trace amounts of gases in the atmosphere. The detection of one or more target gases in the atmosphere is used to indicate a possible subsurface oil and gas deposit. By mapping a plurality of gas targets over a selected survey area, the survey area can be analyzed for measurable concentration anomalies. The anomalies are interpreted along with other exploration data to evaluate the value of an underground deposit. The system includes a differential absorption lidar (DIAL) system with a spectroscopic grade laser light and a light detector. The laser light is continuously tunable in a mid-infrared range, 2 to 5 micrometers, for choosing appropriate wavelengths to measure different gases and avoid absorption bands of interference gases. The laser light has sufficient optical energy to measure atmospheric concentrations of a gas over a path as long as a mile and greater. The detection of the gas is based on optical absorption measurements at specific wavelengths in the open atmosphere. Light that is detected using the light detector contains an absorption signature acquired as the light travels through the atmosphere from the laser source and back to the light detector. The absorption signature of each gas is processed and then analyzed to determine if a potential anomaly exists.

  17. Investigating wind turbine impacts on near-wake flow using profiling Lidar data and large-eddy simulations with an actuator disk model

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Mirocha, Jeffrey D.; Rajewski, Daniel A.; Marjanovic, Nikola; Lundquist, Julie K.; Kosovic, Branko; Draxl, Caroline; Churchfield, Matthew J.

    2015-08-27

    In this study, wind turbine impacts on the atmospheric flow are investigated using data from the Crop Wind Energy Experiment (CWEX-11) and large-eddy simulations (LESs) utilizing a generalized actuator disk (GAD) wind turbine model. CWEX-11 employed velocity-azimuth display (VAD) data from two Doppler lidar systems to sample vertical profiles of flow parameters across the rotor depth both upstream and in the wake of an operating 1.5 MW wind turbine. Lidar and surface observations obtained during four days of July 2011 are analyzed to characterize the turbine impacts on wind speed and flow variability, and to examine the sensitivity of thesemore » changes to atmospheric stability. Significant velocity deficits (VD) are observed at the downstream location during both convective and stable portions of four diurnal cycles, with large, sustained deficits occurring during stable conditions. Variances of the streamwise velocity component, σu, likewise show large increases downstream during both stable and unstable conditions, with stable conditions supporting sustained small increases of σu , while convective conditions featured both larger magnitudes and increased variability, due to the large coherent structures in the background flow. Two representative case studies, one stable and one convective, are simulated using LES with a GAD model at 6 m resolution to evaluate the compatibility of the simulation framework with validation using vertically profiling lidar data in the near wake region. Virtual lidars were employed to sample the simulated flow field in a manner consistent with the VAD technique. Simulations reasonably reproduced aggregated wake VD characteristics, albeit with smaller magnitudes than observed, while σu values in the wake are more significantly underestimated. The results illuminate the limitations of using a GAD in combination with coarse model resolution in the simulation of near wake physics, and validation thereof using VAD data.« less

  18. Wide-angle imaging LIDAR (WAIL): a ground-based instrument for monitoring the thickness and density of optically thick clouds.

    SciTech Connect (OSTI)

    Love, Steven P.; Davis, A. B.; Rohde, C. A.; Ho, Cheng,

    2001-01-01

    Traditional lidar provides little information on dense clouds beyond the range to their base (ceilometry), due to their extreme opacity. At most optical wavelengths, however, laser photons are not absorbed but merely scattered out of the beam, and thus eventually escape the cloud via multiple scattering, producing distinctive extended space- and time-dependent patterns which are, in essence, the cloud's radiative Green functions. These Green functions, essentially 'movies' of the time evolution of the spatial distribution of escaping light, are the primary data products of a new type of lidar: Wide Angle Imaging Lidar (WAIL). WAIL data can be used to infer both optical depth and physical thickness of clouds, and hence the cloud liquid water content. The instrumental challenge is to accommodate a radiance field varying over many orders of magnitude and changing over widely varying time-scales. Our implementation uses a high-speed microchannel plate/crossed delay line imaging detector system with a 60-degree full-angle field of view, and a 532 nm doubled Nd:YAG laser. Nighttime field experiments testing various solutions to this problem show excellent agreement with diffusion theory, and retrievals yield plausible values for the optical and geometrical parameters of the observed cloud decks.

  19. Lithium bromide absorption chiller passes gas conditioning field test

    SciTech Connect (OSTI)

    Lane, M.J.; Huey, M.A.

    1995-07-31

    A lithium bromide absorption chiller has been successfully used to provide refrigeration for field conditioning of natural gas. The intent of the study was to identify a process that could provide a moderate level of refrigeration necessary to meet the quality restrictions required by natural-gas transmission companies, minimize the initial investment risk, and reduce operating expenses. The technology in the test proved comparatively less expensive to operate than a propane refrigeration plant. Volatile product prices and changes in natural-gas transmission requirements have created the need for an alternative to conventional methods of natural-gas processing. The paper describes the problems with the accumulation of condensed liquids in pipelines, gas conditioning, the lithium bromide absorption cycle, economics, performance, and operating and maintenance costs.

  20. Method for making a photodetector with enhanced light absorption

    DOE Patents [OSTI]

    Kane, James (Lawrenceville, NJ)

    1987-05-05

    A photodetector including a light transmissive electrically conducting layer having a textured surface with a semiconductor body thereon. This layer traps incident light thereby enhancing the absorption of light by the semiconductor body. A photodetector comprising a textured light transmissive electrically conducting layer of SnO.sub.2 and a body of hydrogenated amorphous silicon has a conversion efficiency about fifty percent greater than that of comparative cells. The invention also includes a method of fabricating the photodetector of the invention.

  1. Quantum fluctuations and saturable absorption in mesoscale lasers

    SciTech Connect (OSTI)

    Roy-Choudhury, Kaushik [Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089-0484 (United States); Levi, A. F. J. [Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089-0484 (United States); Department of Electrical Engineering, University of Southern California, Los Angeles, California 90089-2533 (United States)

    2011-04-15

    We present a quantum-mechanical treatment of fluctuations and saturable absorption in mesoscale lasers. The time evolution of the density matrix is obtained from numerical integration and field-field and intensity-intensity correlations are calculated to obtain steady-state linewidth and photon statistics. Inclusion of a saturable absorber in the otherwise homogeneous medium is shown to suppress lasing, increase fluctuations, and enhance spontaneous emission near threshold.

  2. Method for processing seismic data to identify anomalous absorption zones

    DOE Patents [OSTI]

    Taner, M. Turhan

    2006-01-03

    A method is disclosed for identifying zones anomalously absorptive of seismic energy. The method includes jointly time-frequency decomposing seismic traces, low frequency bandpass filtering the decomposed traces to determine a general trend of mean frequency and bandwidth of the seismic traces, and high frequency bandpass filtering the decomposed traces to determine local variations in the mean frequency and bandwidth of the seismic traces. Anomalous zones are determined where there is difference between the general trend and the local variations.

  3. Diffraction: Enhanced Light Absorption of Solar Cells and Photodetectors -

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Energy Innovation Portal Solar Thermal Solar Thermal Solar Photovoltaic Solar Photovoltaic Advanced Materials Advanced Materials Find More Like This Return to Search Diffraction: Enhanced Light Absorption of Solar Cells and Photodetectors Sandia National Laboratories Contact SNL About This Technology Publications: PDF Document Publication Market Sheet (890 KB) Technology Marketing SummaryThe solar and photovoltaic industry has grown steadily over the last several years. In order to maintain

  4. Waste heat driven absorption refrigeration process and system

    DOE Patents [OSTI]

    Wilkinson, William H. (Columbus, OH)

    1982-01-01

    Absorption cycle refrigeration processes and systems are provided which are driven by the sensible waste heat available from industrial processes and other sources. Systems are disclosed which provide a chilled water output which can be used for comfort conditioning or the like which utilize heat from sensible waste heat sources at temperatures of less than 170.degree. F. Countercurrent flow equipment is also provided to increase the efficiency of the systems and increase the utilization of available heat.

  5. Hydrogen Absorption Induced Metal Deposition on Palladium and

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Palladium-Alloy Particles - Energy Innovation Portal Hydrogen Absorption Induced Metal Deposition on Palladium and Palladium-Alloy Particles Brookhaven National Laboratory Contact BNL About This Technology <p> High resolution electron micrograph of a palladium nanoparticle coated with a monolayer of platinum</p> High resolution electron micrograph of a palladium nanoparticle coated with a monolayer of platinum Technology Marketing Summary Platinum is an excellent catalyst for

  6. Collision-induced vibrational absorption in molecular hydrogens

    SciTech Connect (OSTI)

    Reddy, S.P.

    1993-05-01

    Collision induced absorption (CIA) spectra of the first overtone bands of H{sub 2}, D{sub 2}, and HD have been recorded for gas densities up to 500 amagat at 77-300 K. Analyses of these spectra reveal that (1) contrary to the observations in the fundamental bands, the contribution of the isotropic overlap interaction to the first overtone bands is negligible, (2) the squares of the matrix elements B{sub 32}(R)/ea{sub o} [= {lambda}{sub 32} exp(-(R-{sigma})/{rho}{sub 32}) + 3 (R/a{sub o}){sup -4}] where the subscripts 3 and 2 represent L and {lambda}, respectively, account for the absorption intensity of the bands and (3) the mixed term, 2,3 {lambda}{sub 32} exp (-(R-{sigma})/{rho}{sub 32}) <{vert_bar}Q{vert_bar}> <{alpha}> (R/a){sup -4}, gives a negative contribution. In the CIA spectra of H{sub 2} in its second overtone region recorded at 77, 201 and 298 K for gas densities up to 1000 amagat, a dip in the Q branch with characteristic Q{sub p} and Q{sub R} components has been observed. The analysis of the absorption profiles reveals, in addition to the previously known effects, the occurrence of the triple-collision transitions of H{sub 2} of the type Q{sub 1}(J) + Q{sub 1}(J) + Q{sub 1}(J) for the first time. From the profile analysis the absorption coefficient of these transitions is obtained.

  7. PROMINENCE PLASMA DIAGNOSTICS THROUGH EXTREME-ULTRAVIOLET ABSORPTION

    SciTech Connect (OSTI)

    Landi, E.; Reale, F.

    2013-07-20

    In this paper, we introduce a new diagnostic technique that uses EUV and UV absorption to determine the electron temperature and column emission measure, as well as the He/H relative abundance of the absorbing plasma. If a realistic assumption on the geometry of the latter can be made and a spectral code such as CHIANTI is used, then this technique can also yield the absorbing plasma hydrogen and electron density. This technique capitalizes on the absorption properties of hydrogen and helium at different wavelength ranges and temperature regimes. Several cases where this technique can be successfully applied are described. This technique works best when the absorbing plasma is hotter than 15,000 K. We demonstrate this technique on AIA observations of plasma absorption during a coronal mass ejection eruption. This technique can be easily applied to existing observations of prominences and cold plasmas in the Sun from almost all space missions devoted to the study of the solar atmosphere, which we list.

  8. Mechanical properties and energy absorption characteristics of a polyurethane foam

    SciTech Connect (OSTI)

    Goods, S.H.; Neuschwanger, C.L.; Henderson, C.; Skala, D.M.

    1997-03-01

    Tension, compression and impact properties of a polyurethane encapsulant foam have been measured as a function of foam density. Significant differences in the behavior of the foam were observed depending on the mode of testing. Over the range of densities examined, both the modulus and the elastic collapse stress of the foam exhibited power-law dependencies with respect to density. The power-law relationship for the modulus was the same for both tension and compression testing and is explained in terms of the elastic compliance of the cellular structure of the foam using a simple geometric model. Euler buckling is used to rationalize the density dependence of the collapse stress. Neither tension nor compression testing yielded realistic measurements of energy absorption (toughness). In the former case, the energy absorption characteristics of the foam were severely limited due to the inherent lack of tensile ductility. In the latter case, the absence of a failure mechanism led to arbitrary measures of energy absorption that were not indicative of true material properties. Only impact testing revealed an intrinsic limitation in the toughness characteristics of the material with respect to foam density. The results suggest that dynamic testing should be used when assessing the shock mitigating qualities of a foam.

  9. A cryogenic circulating advective multi-pass absorption cell

    SciTech Connect (OSTI)

    Stockett, M. H.; Lawler, J. E. [Department of Physics, University of Wisconsin, 1150 University Avenue, Madison, Wisconsin 53706 (United States)

    2012-03-15

    A novel absorption cell has been developed to enable a spectroscopic survey of a broad range of polycyclic aromatic hydrocarbons (PAH) under astrophysically relevant conditions and utilizing a synchrotron radiation continuum to test the still controversial hypothesis that these molecules or their ions could be carriers of the diffuse interstellar bands. The cryogenic circulating advective multi-pass absorption cell resembles a wind tunnel; molecules evaporated from a crucible or injected using a custom gas feedthrough are entrained in a laminar flow of cryogenically cooled buffer gas and advected into the path of the synchrotron beam. This system includes a multi-pass optical White cell enabling absorption path lengths of hundreds of meters and a detection sensitivity to molecular densities on the order of 10{sup 7} cm{sup -3}. A capacitively coupled radio frequency dielectric barrier discharge provides ionized and metastable buffer gas atoms for ionizing the candidate molecules via charge exchange and the Penning effect. Stronger than expected clustering of PAH molecules has slowed efforts to record gas phase PAH spectra at cryogenic temperatures, though such clusters may play a role in other interstellar phenomena.

  10. Heat exchanger bypass system for an absorption refrigeration system

    DOE Patents [OSTI]

    Reimann, Robert C. (Lafayette, NY)

    1984-01-01

    A heat exchanger bypass system for an absorption refrigeration system is disclosed. The bypass system operates to pass strong solution from the generator around the heat exchanger to the absorber of the absorption refrigeration system when strong solution builds up in the generator above a selected level indicative of solidification of strong solution in the heat exchanger or other such blockage. The bypass system includes a bypass line with a gooseneck located in the generator for controlling flow of strong solution into the bypass line and for preventing refrigerant vapor in the generator from entering the bypass line during normal operation of the refrigeration system. Also, the bypass line includes a trap section filled with liquid for providing a barrier to maintain the normal pressure difference between the generator and the absorber even when the gooseneck of the bypass line is exposed to refrigerant vapor in the generator. Strong solution, which may accumulate in the trap section of the bypass line, is diluted, to prevent solidification, by supplying weak solution to the trap section from a purge system for the absorption refrigeration system.

  11. Waste Heat Powered Ammonia Absorption Refrigeration Unit for LPG Recovery

    SciTech Connect (OSTI)

    Donald C, Energy Concepts Co.; Lauber, Eric, Western Refining Co.

    2008-06-20

    An emerging DOE-sponsored technology has been deployed. The technology recovers light ends from a catalytic reformer plant using waste heat powered ammonia absorption refrigeration. It is deployed at the 17,000 bpd Bloomfield, New Mexico refinery of Western Refining Company. The technology recovers approximately 50,000 barrels per year of liquefied petroleum gas that was formerly being flared. The elimination of the flare also reduces CO2 emissions by 17,000 tons per year, plus tons per year reductions in NOx, CO, and VOCs. The waste heat is supplied directly to the absorption unit from the Unifiner effluent. The added cooling of that stream relieves a bottleneck formerly present due to restricted availability of cooling water. The 350oF Unifiner effluent is cooled to 260oF. The catalytic reformer vent gas is directly chilled to minus 25oF, and the FCC column overhead reflux is chilled by 25oF glycol. Notwithstanding a substantial cost overrun and schedule slippage, this project can now be considered a success: it is both profitable and highly beneficial to the environment. The capabilities of directly-integrated waste-heat powered ammonia absorption refrigeration and their benefits to the refining industry have been demonstrated.

  12. Aqueous absorption fluids. Annual report, July 1989-October 1990

    SciTech Connect (OSTI)

    Langeliers, J.; Chandler, T.; Rockenfeller, U.

    1990-11-01

    The report describes the third year of study of aqueous-based working fluids that will allow air-cooled absorption chiller operation. The successful development of such fluids will eliminate the need for cooling towers in gas-fired chiller equipment for residential and unitary markets and possibly allow for building heating with absorber heat. The thermophysical property measurements were completed and the vapor pressure and specific heat data were used to compute the enthalpy of LB621-H2O solutions. Solution film heat transfer coefficients were measured in the test sorber apparatus and a dramatic increase in film heat transfer was observed in the presence of heat transfer additives. Measured equilibrium and film heat transfer data were used in the single-stage absorption cycle computer model to analyze the potential performance of LB621-H2O; the analysis confirmed the superiority of LB621-H2O as a single-stage working fluid. In addition, thermal stability and corrosion rate tests demonstrated that LB621-H2O is stable and non-corrosive in a single-stage absorption chiller environment.

  13. Regional respiratory tract absorption of inhaled reactive gases

    SciTech Connect (OSTI)

    Miller, F.J.; Overton, J.H.; Kimbell, J.S.; Russell, M.L.

    1992-06-29

    Highly reactive gases present unique problems due to the number of factors which must be taken into account to determine regional respiratory tract uptake. The authors reviewed some of the physical, chemical, and biological factors that affect dose and that must be understood to interpret toxicological data, to evaluate experimental dosimetry studies, and to develop dosimetry models. Selected dosimetry experiments involving laboratory animals and humans were discussed, showing the variability and uptake according to animal species and respiratory tract region for various reactive gases. New experimental dosimetry approaches, such as those involving isotope ratio mass spectroscopy and cyclotron generation reactive gases, were discussed that offer great promise for improving the ability to study regional respiratory tract absorption of reactive gases. Various dosimetry modeling applications were discussed which demonstrate: the importance of airflow patterns for site-specific dosimetry in the upper respiratory tract, the influence of the anatomical model used to make inter- and intraspecies dosimetric comparisons, the influence of tracheobronchial path length on predicted dose curves, and the implications of ventilatory unit structure and volume on dosimetry and response. Collectively, these examples illustrate important aspects of regional respiratory tract absorption of inhaled reactive gases. Given the complex nature of extent and pattern of injury in the respiratory tract from exposure to reactive gases, understanding interspecies differences in the absorption of reactive gases will continue to be an important area for study.

  14. Horizontal Velocity and Variance Measurements in the Stable Boundary Layer Using Doppler Lidar: Sensitivity to Averaging Procedures

    SciTech Connect (OSTI)

    Pichugina, Y. L.; Banta, R. M.; Kelley, N. D.; Jonkman, B. J.; Tucker, S. C.; Newsom, R. K.; Brewer, W. A.

    2008-08-01

    Quantitative data on turbulence variables aloft--above the region of the atmosphere conveniently measured from towers--have been an important but difficult measurement need for advancing understanding and modeling of the stable boundary layer (SBL). Vertical profiles of streamwise velocity variances obtained from NOAA's high-resolution Doppler lidar (HRDL), which have been shown to be approximately equal to turbulence kinetic energy (TKE) for stable conditions, are a measure of the turbulence in the SBL. In the present study, the mean horizontal wind component U and variance {sigma}2u were computed from HRDL measurements of the line-of-sight (LOS) velocity using a method described by Banta et al., which uses an elevation (vertical slice) scanning technique. The method was tested on datasets obtained during the Lamar Low-Level Jet Project (LLLJP) carried out in early September 2003, near the town of Lamar in southeastern Colorado. This paper compares U with mean wind speed obtained from sodar and sonic anemometer measurements. The results for the mean U and mean wind speed measured by sodar and in situ instruments for all nights of LLLJP show high correlation (0.71-0.97), independent of sampling strategies and averaging procedures, and correlation coefficients consistently >0.9 for four high-wind nights, when the low-level jet speeds exceeded 15 m s{sup -1} at some time during the night. Comparison of estimates of variance, on the other hand, proved sensitive to both the spatial and temporal averaging parameters. Several series of averaging tests are described, to find the best correlation between TKE calculated from sonic anemometer data at several tower levels and lidar measurements of horizontal-velocity variance {sigma}{sup 2}{sub u}. Because of the nonstationarity of the SBL data, the best results were obtained when the velocity data were first averaged over intervals of 1 min, and then further averaged over 3-15 consecutive 1-min intervals, with best results for the 10- and 15-min averaging periods. For these cases, correlation coefficients exceeded 0.9. As a part of the analysis, Eulerian integral time scales ({tau}) were estimated for the four high-wind nights. Time series of {tau} through each night indicated erratic behavior consistent with the nonstationarity. Histograms of {tau} showed a mode at 4-5 s, but frequent occurrences of larger {tau} values, mostly between 10 and 100 s.

  15. Guide to Developing Air-Cooled Lithium Bromide (LiBr) Absorption...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Developing Air-Cooled Lithium Bromide (LiBr) Absorption for CHP Applications, April 2005 Guide to Developing Air-Cooled Lithium Bromide (LiBr) Absorption for CHP Applications, ...

  16. Guide to Developing Air-Cooled Lithium Bromide (LiBr) Absorption...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Guide to Developing Air-Cooled Lithium Bromide (LiBr) Absorption for CHP Applications, April 2005 Guide to Developing Air-Cooled Lithium Bromide (LiBr) Absorption for CHP...

  17. X-ray absorption near-edge spectra of overdoped La 2 - x Sr x...

    Office of Scientific and Technical Information (OSTI)

    X-ray absorption near-edge spectra of overdoped La 2 - x Sr x CuO 4 high- T c superconductors Citation Details In-Document Search Title: X-ray absorption near-edge spectra of...

  18. New packing in absorption systems for trapping benzene from coke-oven gas

    SciTech Connect (OSTI)

    V.V. Grabko; V.M. Li; T.A. Shevchenko; M.A. Solov'ev

    2009-07-15

    The efficiency of benzene removal from coke-oven gas in absorption units OAO Alchevskkoks with new packing is assessed.

  19. Advantages and disadvantages of using absorption chillers to lower utility bills

    SciTech Connect (OSTI)

    Kistler, P.

    1997-04-01

    Absorption chillers have a proven history of providing low-cost reliable cooling and should continue to do so in the future. Absorption chiller systems can provide significant energy savings for a particular application. To maximize savings, the various system arrangements should be evaluated; for example, single effect versus double effect, chiller versus chiller/heater, straight absorption chiller or the electric/absorption hybrid.

  20. On the relationship among cloud turbulence, droplet formation and drizzle as viewed by Doppler radar, microwave radiometer and lidar

    SciTech Connect (OSTI)

    Feingold, G.; Frisch, A.S.; Cotton, W.R.

    1999-09-01

    Cloud radar, microwave radiometer, and lidar remote sensing data acquired during the Atlantic Stratocumulus Transition Experiment (ASTEX) are analyzed to address the relationship between (1) drop number concentration and cloud turbulence as represented by vertical velocity and vertical velocity variance and (2) drizzle formation and cloud turbulence. Six cases, each of about 12 hours duration, are examined; three of these cases are characteristic of nondrizzling boundary layers and three of drizzling boundary layers. In all cases, microphysical retrievals are only performed when drizzle is negligible (radar reflectivity{lt}{minus}17dBZ). It is shown that for the cases examined, there is, in general, no correlation between drop concentration and cloud base updraft strength, although for two of the nondrizzling cases exhibiting more classical stratocumulus features, these two parameters are correlated. On drizzling days, drop concentration and cloud-base vertical velocity were either not correlated or negatively correlated. There is a significant positive correlation between drop concentration and mean in-cloud vertical velocity variance for both nondrizzling boundary layers (correlation coefficient r=0.45) and boundary layers that have experienced drizzle (r=0.38). In general, there is a high correlation (r{gt}0.5) between radar reflectivity and in-cloud vertical velocity variance, although one of the boundary layers that experienced drizzle exhibited a negative correlation between these parameters. However, in the subcloud region, all boundary layers that experienced drizzle exhibit a negative correlation between radar reflectivity and vertical velocity variance. {copyright} 1999 American Geophysical Union

  1. Joint retrievals of cloud and drizzle in marine boundary layer clouds using ground-based radar, lidar and zenith radiances

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Fielding, M. D.; Chiu, J. C.; Hogan, R. J.; Feingold, G.; Eloranta, E.; O'Connor, E. J.; Cadeddu, M. P.

    2015-02-16

    Active remote sensing of marine boundary-layer clouds is challenging as drizzle drops often dominate the observed radar reflectivity. We present a new method to simultaneously retrieve cloud and drizzle vertical profiles in drizzling boundary-layer cloud using surface-based observations of radar reflectivity, lidar attenuated backscatter, and zenith radiances. Specifically, the vertical structure of droplet size and water content of both cloud and drizzle is characterised throughout the cloud. An ensemble optimal estimation approach provides full error statistics given the uncertainty in the observations. To evaluate the new method, we first perform retrievals using synthetic measurements from large-eddy simulation snapshots of cumulusmore » under stratocumulus, where cloud water path is retrieved with an error of 31 g m−2. The method also performs well in non-drizzling clouds where no assumption of the cloud profile is required. We then apply the method to observations of marine stratocumulus obtained during the Atmospheric Radiation Measurement MAGIC deployment in the northeast Pacific. Here, retrieved cloud water path agrees well with independent 3-channel microwave radiometer retrievals, with a root mean square difference of 10–20 g m−2.« less

  2. Joint retrievals of cloud and drizzle in marine boundary layer clouds using ground-based radar, lidar and zenith radiances

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Fielding, M. D.; Chiu, J. C.; Hogan, R. J.; Feingold, G.; Eloranta, E.; O'Connor, E. J.; Cadeddu, M. P.

    2015-07-02

    Active remote sensing of marine boundary-layer clouds is challenging as drizzle drops often dominate the observed radar reflectivity. We present a new method to simultaneously retrieve cloud and drizzle vertical profiles in drizzling boundary-layer clouds using surface-based observations of radar reflectivity, lidar attenuated backscatter, and zenith radiances under conditions when precipitation does not reach the surface. Specifically, the vertical structure of droplet size and water content of both cloud and drizzle is characterised throughout the cloud. An ensemble optimal estimation approach provides full error statistics given the uncertainty in the observations. To evaluate the new method, we first perform retrievalsmore » using synthetic measurements from large-eddy simulation snapshots of cumulus under stratocumulus, where cloud water path is retrieved with an error of 31 g m-2. The method also performs well in non-drizzling clouds where no assumption of the cloud profile is required. We then apply the method to observations of marine stratocumulus obtained during the Atmospheric Radiation Measurement MAGIC deployment in the Northeast Pacific. Here, retrieved cloud water path agrees well with independent three-channel microwave radiometer retrievals, with a root mean square difference of 10–20 g m-2.« less

  3. Absorption Features in Spectra of Magnetized Neutron Stars

    SciTech Connect (OSTI)

    Suleimanov, V.; Hambaryan, V.; Neuhaeuser, R.; Potekhin, A. Y.; Pavlov, G. G.; Adelsberg, M. van; Werner, K.

    2011-09-21

    The X-ray spectra of some magnetized isolated neutron stars (NSs) show absorption features with equivalent widths (EWs) of 50-200 eV, whose nature is not yet well known.To explain the prominent absorption features in the soft X-ray spectra of the highly magnetized (B{approx}10{sup 14} G) X-ray dim isolated NSs (XDINSs), we theoretically investigate different NS local surface models, including naked condensed iron surfaces and partially ionized hydrogen model atmospheres, with semi-infinite and thin atmospheres above the condensed surface. We also developed a code for computing light curves and integral emergent spectra of magnetized neutron stars with various temperature and magnetic field distributions over the NS surface. We compare the general properties of the computed and observed light curves and integral spectra for XDINS RBS 1223 and conclude that the observations can be explained by a thin hydrogen atmosphere above the condensed iron surface, while the presence of a strong toroidal magnetic field component on the XDINS surface is unlikely.We suggest that the harmonically spaced absorption features in the soft X-ray spectrum of the central compact object (CCO) 1E 1207.4-5209 (hereafter 1E 1207) correspond to peaks in the energy dependence of the free-free opacity in a quantizing magnetic field, known as quantum oscillations. To explore observable properties of these quantum oscillations, we calculate models of hydrogen NS atmospheres with B{approx}10{sup 10}-10{sup 11} G(i.e., electron cyclotron energy E{sub c,e}{approx}0.1-1 keV) and T{sub eff} = 1-3 MK. Such conditions are thought to be typical for 1E 1207. We show that observable features at the electron cyclotron harmonics with EWs {approx_equal}100-200 eV can arise due to these quantum oscillations.

  4. Absorption-emission optrode and methods of use thereof

    DOE Patents [OSTI]

    Hirschfeld, T.B.

    1990-05-29

    A method and apparatus are described for monitoring the physical and chemical properties of a sample fluid by measuring an optical signal generated by a fluorescent substance and modulated by an absorber substance. The emission band of the fluorescent substance overlaps the absorption band of the absorber substance, and the degree of overlap is dependent on the physical and chemical properties of the sample fluid. The fluorescent substance and absorber substance are immobilized on a substrate so that an effective number of molecules thereof are sufficiently close for resonant energy transfer to occur, thereby providing highly efficient modulation of the fluorescent emissions of the fluorescent substance by the absorber substance. 4 figs.

  5. A hybrid absorption-adsorption method to efficiently capture carbon |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Center for Gas SeparationsRelevant to Clean Energy Technologies | Blandine Jerome hybrid absorption-adsorption method to efficiently capture carbon Previous Next List Huang Liu, Bei Liu, Li-Chiang Lin, Guangjin Chen, Yuqing Wu, Jin Wang, Xueteng Gao, Yining Lv, Yong Pan, Xiaoxin Zhang, Xianren Zhang, Lanying Yang, Changyu Sun, Berend Smit & Wenchuan Wang, Nature Communications 5, 5147 (2014) DOI: 10.1038/ncomms6147 ncomms6147-f6 Abstract: Removal of carbon dioxide is an essential step in

  6. IHT: Tools for Computing Insolation Absorption by Particle Laden Flows

    SciTech Connect (OSTI)

    Grout, R. W.

    2013-10-01

    This report describes IHT, a toolkit for computing radiative heat exchange between particles. Well suited for insolation absorption computations, it is also has potential applications in combustion (sooting flames), biomass gasification processes and similar processes. The algorithm is based on the 'Photon Monte Carlo' approach and implemented in a library that can be interfaced with a variety of computational fluid dynamics codes to analyze radiative heat transfer in particle-laden flows. The emphasis in this report is on the data structures and organization of IHT for developers seeking to use the IHT toolkit to add Photon Monte Carlo capabilities to their own codes.

  7. High Energy Absorption Top Nozzle For A Nuclaer Fuel Assembly

    DOE Patents [OSTI]

    Sparrow, James A. (Irmo, SC); Aleshin, Yuriy (Columbia, SC); Slyeptsov, Aleksey (Columbia, SC)

    2004-05-18

    A high energy absorption top nozzle for a nuclear fuel assembly that employs an elongated upper tubular housing and an elongated lower tubular housing slidable within the upper tubular housing. The upper and lower housings are biased away from each other by a plurality of longitudinally extending springs that are restrained by a longitudinally moveable piston whose upward travel is limited within the upper housing. The energy imparted to the nozzle by a control rod scram is mostly absorbed by the springs and the hydraulic affect of the piston within the nozzle.

  8. Absorption-emission optrode and methods of use thereof

    DOE Patents [OSTI]

    Hirschfeld, Tomas B. (Livermore, CA)

    1990-01-01

    A method and apparatus for monitoring the physical and chemical properties of a sample fluid by measuring an optical signal generated by a fluorescent substance and modulated by an absorber substance. The emission band of the fluorescent substance overlaps the absorption band of the absorber substance, and the degree of overlap is dependent on the physical and chemical properties of the sample fluid. The fluorescent substance and absorber substance are immobilized on a substrate so that an effective number of molecules thereof are sufficiently close for resonant energy transfer to occur, thereby providing highly efficient modulation of the fluorescent emissions of the fluorescent substance by the absorber substance.

  9. Use Low-Grade Waste Steam to Power Absorption Chillers | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy Low-Grade Waste Steam to Power Absorption Chillers Use Low-Grade Waste Steam to Power Absorption Chillers This tip sheet on waste steam to power absorption chillers provides how-to advice for improving steam systems using low-cost, proven practices and technologies. STEAM TIP SHEET #14 PDF icon Use Low-Grade Waste Steam to Power Absorption Chillers (January 2012) More Documents & Publications Guide to Developing Air-Cooled Lithium Bromide (LiBr) Absorption for CHP Applications,

  10. Use Low-Grade Waste Steam to Power Absorption Chillers | Department of

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Energy Use Low-Grade Waste Steam to Power Absorption Chillers Use Low-Grade Waste Steam to Power Absorption Chillers This tip sheet on waste steam to power absorption chillers provides how-to advice for improving steam systems using low-cost, proven practices and technologies. STEAM TIP SHEET #14 PDF icon Use Low-Grade Waste Steam to Power Absorption Chillers (January 2012) More Documents & Publications Guide to Developing Air-Cooled Lithium Bromide (LiBr) Absorption for CHP

  11. Low level absorptance measurements and scans of high performance optical coatings for atomic vapor laser isotope separation applications

    SciTech Connect (OSTI)

    Chow, R.; Taylor, J.R.; Wu, Z.L.; Krupka, R.; Yang, T.

    1998-01-24

    A surface thermal lensing and a radiometric technique was used to characterize the absorptance dependence on time, power, site, and technique of low absorptance optical multilayered coatings.

  12. THE ABSORPTION OF HYDROGEN ON LOW PRESSURE HYDRIDE MATERIALS

    SciTech Connect (OSTI)

    Morgan, G.; Korinko, P.

    2012-04-03

    For this study, hydrogen getter materials (Zircaloy-4 and pure zirconium) that have a high affinity for hydrogen (and low overpressure) have been investigated to determine the hydrogen equilibrium pressure on Zircaloy-4 and pure zirconium. These materials, as with most getter materials, offered significant challenges to overcome given the low hydrogen equilibrium pressure for the temperature range of interest. Hydrogen-zirconium data exists for pure zirconium at 500 C and the corresponding hydrogen overpressure is roughly 0.01 torr. This manuscript presents the results of the equilibrium pressures for the absorption and desorption of hydrogen on zirconium materials at temperatures ranging from 400 C to 600 C. The equilibrium pressures in this temperature region range from 150 mtorr at 600 C to less than 0.1 mtorr at 400 C. It has been shown that the Zircaloy-4 and zirconium samples are extremely prone to surface oxidation prior to and during heating. This oxidation precludes the hydrogen uptake, and therefore samples must be heated under a minimum vacuum of 5 x 10{sup -6} torr. In addition, the Zircaloy-4 samples should be heated at a sufficiently low rate to maintain the system pressure below 0.5 mtorr since an increase in pressure above 0.5 mtorr could possibly hinder the H{sub 2} absorption kinetics due to surface contamination. The results of this study and the details of the testing protocol will be discussed.

  13. Effects of thermal motion on electromagnetically induced absorption

    SciTech Connect (OSTI)

    Tilchin, E.; Wilson-Gordon, A. D.; Firstenberg, O. [Department of Chemistry, Bar-Ilan University, Ramat Gan IL-52900 (Israel); Department of Physics, Technion-Israel Institute of Technology, Haifa IL-32000 (Israel)

    2011-05-15

    We describe the effect of thermal motion and buffer-gas collisions on a four-level closed N system interacting with strong pump(s) and a weak probe. This is the simplest system that experiences electromagnetically induced absorption (EIA) due to transfer of coherence via spontaneous emission from the excited state to the ground state. We investigate the influence of Doppler broadening, velocity-changing collisions (VCC), and phase-changing collisions (PCC) with a buffer gas on the EIA spectrum of optically active atoms. In addition to exact expressions, we present an approximate solution for the probe absorption spectrum, which provides physical insight into the behavior of the EIA peak due to VCC, PCC, and the wave-vector difference between the pump and probe beams. VCC are shown to produce a wide pedestal at the base of the EIA peak, which is scarcely affected by the pump-probe angular deviation, whereas the sharp central EIA peak becomes weaker and broader due to the residual Doppler-Dicke effect. Using diffusionlike equations for the atomic coherences and populations, we construct a spatial-frequency filter for a spatially structured probe beam and show that Ramsey narrowing of the EIA peak is obtained for beams of finite width.

  14. Hydrogen Absorption in Pd-based Nanostructures - Final Report

    SciTech Connect (OSTI)

    David Lederman

    2012-10-22

    Pd is known to absorb hydrogen. Molecules are normally chemisorbed at the surface in a process where the molecule breaks into two hydrogen atoms, and the protons are then absorbed into the bulk. This process consists of electron filling holes in the Pd 4d band near the Fermi energy, which due to the high density of states at the Fermi energy, is an energetically favorable process. Our aim with this project was to determine possible changes in magnetic properties with Pd nm-length-scale thick layers intercalated by magnetic materials. Before the start of this work, the literature indicated that there were several possible scenarios by which this could happen: i) the Pd will be magnetized due to a proximity effect with nearby magnetic layers, resulting in changes in the magnetization due to H2 absorption; ii) some H will be absorbed into the magnetic layers, causing a change in the magnetic exchange interactions; or iii) absorption of H2 will cause an expansion of the lattice, resulting in a magnetoelastic effect which changes the magnetic properties.

  15. Absorption process for producing oxygen and nitrogen and solution therefor

    DOE Patents [OSTI]

    Roman, I.C.; Baker, R.W.

    1990-09-25

    Process for the separation and purification of oxygen and nitrogen is disclosed which utilizes solutions of oxygen carriers to selectively absorb oxygen from a gaseous stream, leaving nitrogen as a byproduct. In the process, an oxygen carrier capable of reversibly binding molecular oxygen is dissolved in a solvent solution, which absorbs oxygen from an oxygen-containing gaseous feed stream such as atmospheric air and desorbs oxygen to a gaseous product stream. The feed stream is maintained at a sufficiently high oxygen pressure to keep the oxygen carrier in its oxygenated form during absorption, while the product stream is maintained at a sufficiently low oxygen pressure to keep the carrier in its deoxygenated form during desorption. In an alternate mode of operation, the carrier solution is maintained at a sufficiently low temperature and high oxygen pressure to keep the oxygen carrier in its oxygenated form during absorption, and at a sufficiently high temperature to keep the carrier in its deoxygenated form during desorption. Under such conditions, exceptionally high oxygen concentrations on the order of 95% to 99% are obtained, as well as a long carrier lifetime in excess of 3 months, making the process commercially feasible. 1 figure

  16. Triple loop heat exchanger for an absorption refrigeration system

    DOE Patents [OSTI]

    Reimann, Robert C. (Lafayette, NY)

    1984-01-01

    A triple loop heat exchanger for an absorption refrigeration system is disclosed. The triple loop heat exchanger comprises portions of a strong solution line for conducting relatively hot, strong solution from a generator to a solution heat exchanger of the absorption refrigeration system, conduit means for conducting relatively cool, weak solution from the solution heat exchanger to the generator, and a bypass system for conducting strong solution from the generator around the strong solution line and around the solution heat exchanger to an absorber of the refrigeration system when strong solution builds up in the generator to an undesirable level. The strong solution line and the conduit means are in heat exchange relationship with each other in the triple loop heat exchanger so that, during normal operation of the refrigeration system, heat is exchanged between the relatively hot, strong solution flowing through the strong solution line and the relatively cool, weak solution flowing through the conduit means. Also, the strong solution line and the bypass system are in heat exchange relationship in the triple loop heat exchanger so that if the normal flow path of relatively hot, strong solution flowing from the generator to an absorber is blocked, then this relatively, hot strong solution which will then be flowing through the bypass system in the triple loop heat exchanger, is brought into heat exchange relationship with any strong solution which may have solidified in the strong solution line in the triple loop heat exchanger to thereby aid in desolidifying any such solidified strong solution.

  17. Membrane-Based Absorption Refrigeration Systems: Nanoengineered Membrane-Based Absorption Cooling for Buildings Using Unconcentrated Solar & Waste Heat

    SciTech Connect (OSTI)

    2010-09-01

    BEETIT Project: UFL is improving a refrigeration system that uses low quality heat to provide the energy needed to drive cooling. This system, known as absorption refrigeration system (ARS), typically consists of large coils that transfer heat. Unfortunately, these large heat exchanger coils are responsible for bulkiness and high cost of ARS. UFL is using new materials as well as system design innovations to develop nanoengineered membranes to allow for enhanced heat exchange that reduces bulkiness. UFL’s design allows for compact, cheaper and more reliable use of ARS that use solar or waste heat.

  18. A frequency-agile lidar for simultaneous measurement of temperature and radial wind in the mesopause region without sodium density contamination

    SciTech Connect (OSTI)

    White, M.; Golias, D.; Krueger, D.A.; She, C.Y.

    1996-12-31

    With early and ongoing climatological surveys established, continuing observations of the mesopause region over Fort Collins, Colorado are discussed, emphasizing the modification of Colorado State University`s two frequency lidar for simultaneous measurement of temperature vis Doppler Broadening and radial wind via Doppler shift. The application of a frequency-agile, tandem acousto-optical modulator system for three-frequency temperature/wind measurements free of contamination from atmospheric Na density fluctuations, as well as frequency characterization of this new apparatus, and future applications are considered.

  19. Pulsed laser linescanner for a backscatter absorption gas imaging system

    DOE Patents [OSTI]

    Kulp, Thomas J.; Reichardt, Thomas A.; Schmitt, Randal L.; Bambha, Ray P.

    2004-02-10

    An active (laser-illuminated) imaging system is described that is suitable for use in backscatter absorption gas imaging (BAGI). A BAGI imager operates by imaging a scene as it is illuminated with radiation that is absorbed by the gas to be detected. Gases become "visible" in the image when they attenuate the illumination creating a shadow in the image. This disclosure describes a BAGI imager that operates in a linescanned manner using a high repetition rate pulsed laser as its illumination source. The format of this system allows differential imaging, in which the scene is illuminated with light at least 2 wavelengths--one or more absorbed by the gas and one or more not absorbed. The system is designed to accomplish imaging in a manner that is insensitive to motion of the camera, so that it can be held in the hand of an operator or operated from a moving vehicle.

  20. Light absorption cell combining variable path and length pump

    DOE Patents [OSTI]

    Prather, W.S.

    1993-12-07

    A device is described for use in making spectrophotometric measurements of fluid samples. In particular, the device is a measurement cell containing a movable and a fixed lens with a sample of the fluid there between and through which light shines. The cell is connected to a source of light and a spectrophotometer via optic fibers. Movement of the lens varies the path length and also pumps the fluid into and out of the cell. Unidirectional inlet and exit valves cooperate with the movable lens to assure a one-way flow of fluid through the cell. A linear stepper motor controls the movement of the lens and cycles it from a first position closer to the fixed lens and a second position farther from the fixed lens, preferably at least 10 times per minute for a nearly continuous stream of absorption spectrum data. 2 figures.

  1. Optimum hot water temperature for absorption solar cooling

    SciTech Connect (OSTI)

    Lecuona, A.; Ventas, R.; Venegas, M.; Salgado, R.; Zacarias, A.

    2009-10-15

    The hot water temperature that maximizes the overall instantaneous efficiency of a solar cooling facility is determined. A modified characteristic equation model is used and applied to single-effect lithium bromide-water absorption chillers. This model is based on the characteristic temperature difference and serves to empirically calculate the performance of real chillers. This paper provides an explicit equation for the optimum temperature of vapor generation, in terms of only the external temperatures of the chiller. The additional data required are the four performance parameters of the chiller and essentially a modified stagnation temperature from the detailed model of the thermal collector operation. This paper presents and discusses the results for small capacity machines for air conditioning of homes and small buildings. The discussion highlights the influence of the relevant parameters. (author)

  2. Commercial absorption chiller models for evaluation of control strategies

    SciTech Connect (OSTI)

    Koeppel, E.A.; Klein, S.A.; Mitchell, J.W.

    1995-08-01

    A steady-state computer simulation model of a direct fired double-effect water-lithium bromide absorption chiller in the parallel-flow configuration was developed from first principles. Unknown model parameters such as heat transfer coefficients were determined by matching the model`s calculated state points and coefficient of performance (COP) against nominal full-load operating data and COPs obtained from a manufacturer`s catalog. The model compares favorably with the manufacturer`s performance ratings for varying water circuit (chilled and cooling) temperatures at full load conditions and for chiller part-load performance. The model was used (1) to investigate the effect of varying the water circuit flow rates with the chiller load and (2) to optimize chiller part-load performance with respect to the distribution and flow of the weak solution.

  3. Light absorption cell combining variable path and length pump

    DOE Patents [OSTI]

    Prather, William S. (2419 Dickey Rd., Augusta, GA 30906)

    1993-01-01

    A device for use in making spectrophotometric measurements of fluid samples. In particular, the device is a measurement cell containing a movable and a fixed lens with a sample of the fluid therebetween and through which light shines. The cell is connected to a source of light and a spectrophotometer via optic fibers. Movement of the lens varies the path length and also pumps the fluid into and out of the cell. Unidirectional inlet and exit valves cooperate with the movable lens to assure a one-way flow of fluid through the cell. A linear stepper motor controls the movement of the lens and cycles it from a first position closer to the fixed lens and a second position farther from the fixed lens, preferably at least 10 times per minute for a nearly continuous stream of absorption spectrum data.

  4. Femtosecond Chirp-Free Transient Absorption Method And Apparatus

    DOE Patents [OSTI]

    McBranch, Duncan W.; Klimov, Victor I.

    2001-02-20

    A method and apparatus for femtosecond transient absorption comprising phase-sensitive detection, spectral scanning and simultaneous controlling of a translation stage to obtain TA spectra information having at least a sensitivity two orders of magnitude higher than that for single-shot methods, with direct, simultaneous compensation for chirp as the data is acquired. The present invention includes a amplified delay translation stage which generates a splittable frequency-doubled laser signal at a predetermined frequency f, a controllable means for synchronously modulating one of the laser signals at a repetition rate of f/2, applying the laser signals to a material to be sample, and acquiring data from the excited sample while simultaneously controlling the controllable means for synchronously modulating.

  5. Multi-spectral optical absorption in substrate-free nanowire arrays

    SciTech Connect (OSTI)

    Zhang, Junpeng; Chia, Andrew; Boulanger, Jonathan; LaPierre, Ray; Dhindsa, Navneet; Khodadad, Iman; Saini, Simarjeet

    2014-09-22

    A method is presented of fabricating gallium arsenide (GaAs) nanowire arrays of controlled diameter and period by reactive ion etching of a GaAs substrate containing an indium gallium arsenide (InGaP) etch stop layer, allowing the precise nanowire length to be controlled. The substrate is subsequently removed by selective etching, using the same InGaP etch stop layer, to create a substrate-free GaAs nanowire array. The optical absorptance of the nanowire array was then directly measured without absorption from a substrate. We directly observe absorptance spectra that can be tuned by the nanowire diameter, as explained with rigorous coupled wave analysis. These results illustrate strong optical absorption suitable for nanowire-based solar cells and multi-spectral absorption for wavelength discriminating photodetectors. The solar-weighted absorptance above the bandgap of GaAs was 94% for a nanowire surface coverage of only 15%.

  6. Integrated vacuum absorption steam cycle gas separation (Patent) | SciTech

    Office of Scientific and Technical Information (OSTI)

    Connect SciTech Connect Search Results Patent: Integrated vacuum absorption steam cycle gas separation Citation Details In-Document Search Title: Integrated vacuum absorption steam cycle gas separation Methods and systems for separating a targeted gas from a gas stream emitted from a power plant. The gas stream is brought into contact with an absorption solution to preferentially absorb the targeted gas to be separated from the gas stream so that an absorbed gas is present within the

  7. Size Dependence of Two-Photon Absorption in Semiconductor Quantum Dots

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect Size Dependence of Two-Photon Absorption in Semiconductor Quantum Dots Citation Details In-Document Search Title: Size Dependence of Two-Photon Absorption in Semiconductor Quantum Dots Quantum confinement plays an important role in the optical properties of semiconductor quantum dots (QDs). In this work, we combine experiment and modeling to systematically investigate the size dependence of the degenerate two-photon absorption (TPA) of below-band-gap

  8. VARIABLE SODIUM ABSORPTION IN A LOW-EXTINCTION TYPE Ia SUPERNOVA (Journal

    Office of Scientific and Technical Information (OSTI)

    Article) | SciTech Connect VARIABLE SODIUM ABSORPTION IN A LOW-EXTINCTION TYPE Ia SUPERNOVA Citation Details In-Document Search Title: VARIABLE SODIUM ABSORPTION IN A LOW-EXTINCTION TYPE Ia SUPERNOVA Recent observations have revealed that some Type Ia supernovae exhibit narrow, time-variable Na I D absorption features. The origin of the absorbing material is controversial, but it may suggest the presence of circumstellar gas in the progenitor system prior to the explosion, with significant

  9. The Future of Absorption Technology in America: A Critical Look at the

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Impact of Building, Cooling, Heating, and Power (BCHP) and Innovation, June 2000 | Department of Energy The Future of Absorption Technology in America: A Critical Look at the Impact of Building, Cooling, Heating, and Power (BCHP) and Innovation, June 2000 The Future of Absorption Technology in America: A Critical Look at the Impact of Building, Cooling, Heating, and Power (BCHP) and Innovation, June 2000 Edmond Carré developed the first absorption machine in 1850, using water and sulfuric

  10. The Ability of MM5 to Simulate Ice Clouds: Systematic Comparison between Simulated and Measured Fluxes and Lidar/Radar Profiles at SIRTA Atmospheric Observatory

    SciTech Connect (OSTI)

    Chiriaco, M.; Vautard, R.; Chepfer, H.; Haeffelin, M.; Wanherdrick, Y.; Morille, Y.; Protat, A.; Dudhia, J.

    2005-03-18

    Ice clouds play a major role in the radiative energy budget of the Earth-atmosphere system (Liou 1986). Their radiative effect is governed primarily by the equilibrium between their albedo and greenhouse effects. Both macrophysical and microphysical properties of ice clouds regulate this equilibrium. For quantifying the effect of these clouds onto climate and weather systems, they must be properly characterized in atmospheric models. In this paper we use remote-sensing measurements from the SIRTA ground based atmospheric observatory (Site Instrumental de Recherche par Teledetection Atmospherique, http://sirta.lmd.polytechnique.fr). Lidar and radar observations taken over 18 months are used, in order to gain statistical confidence in the model evaluation. Along this period of time, 62 days are selected for study because they contain parts of ice clouds. We use the ''model to observations'' approach by simulating lidar and radar signals from MM5 outputs. Other more classical variables such as shortwave and longwave radiative fluxes are also used. Four microphysical schemes, among which that proposed by Reisner et al. (1998) with original or modified parameterizations of particle terminal fall velocities (Zurovac-Jevtic and Zhang 2003, Heymsfield and Donner 1990), and the simplified Dudhia (1989) scheme are evaluated in this study.

  11. A Technical and Economic Analysis of an Innovative Two-Step Absorption...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Economic Analysis of an Innovative Two-Step Absorption System for Utilizing Low-Temperature Geothermal Resources to Condition Commercial Buildings A Technical and Economic Analysis ...

  12. X-Ray Absorption Spectroscopic Study of Sodium Iodide and Iodine...

    Office of Scientific and Technical Information (OSTI)

    Supercapacitor Citation Details In-Document Search Title: X-Ray Absorption Spectroscopic Study of Sodium Iodide and Iodine Mediators in a Solid-State Supercapacitor ...

  13. The Effect of Gas Absorption on the Scattered Radiation in the...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Gas Absorption on the Scattered Radiation in the Solar Almucantar: Results of Numerical Simulation T. Yu. Chesnokova, K. M. Firsov, I. M. Nasrtdinov, S. M. Sakerin, V. V....

  14. Using Radar, Lidar, and Radiometer measurements to Classify Cloud Type and Study Middle-Level Cloud Properties

    SciTech Connect (OSTI)

    Wang, Zhien

    2010-06-29

    The project is mainly focused on the characterization of cloud macrophysical and microphysical properties, especially for mixed-phased clouds and middle level ice clouds by combining radar, lidar, and radiometer measurements available from the ACRF sites. First, an advanced mixed-phase cloud retrieval algorithm will be developed to cover all mixed-phase clouds observed at the ACRF NSA site. The algorithm will be applied to the ACRF NSA observations to generate a long-term arctic mixed-phase cloud product for model validations and arctic mixed-phase cloud processes studies. To improve the representation of arctic mixed-phase clouds in GCMs, an advanced understanding of mixed-phase cloud processes is needed. By combining retrieved mixed-phase cloud microphysical properties with in situ data and large-scale meteorological data, the project aim to better understand the generations of ice crystals in supercooled water clouds, the maintenance mechanisms of the arctic mixed-phase clouds, and their connections with large-scale dynamics. The project will try to develop a new retrieval algorithm to study more complex mixed-phase clouds observed at the ACRF SGP site. Compared with optically thin ice clouds, optically thick middle level ice clouds are less studied because of limited available tools. The project will develop a new two wavelength radar technique for optically thick ice cloud study at SGP site by combining the MMCR with the W-band radar measurements. With this new algorithm, the SGP site will have a better capability to study all ice clouds. Another area of the proposal is to generate long-term cloud type classification product for the multiple ACRF sites. The cloud type classification product will not only facilitates the generation of the integrated cloud product by applying different retrieval algorithms to different types of clouds operationally, but will also support other research to better understand cloud properties and to validate model simulations. The ultimate goal is to improve our cloud classification algorithm into a VAP.

  15. Quantitative infrared absorption cross sections of isoprene for atmospheric measurements

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Brauer, C. S.; Blake, T. A.; Guenther, A. B.; Sharpe, S. W.; Sams, R. L.; Johnson, T. J.

    2014-11-19

    Isoprene (C5H8, 2-methyl-1,3-butadiene) is a volatile organic compound (VOC) and is one of the primary contributors to annual global VOC emissions. Isoprene is produced primarily by vegetation as well as anthropogenic sources, and its OH- and O3-initiated oxidations are a major source of atmospheric oxygenated organics. Few quantitative infrared studies have been reported for isoprene, limiting the ability to quantify isoprene emissions via remote or in situ infrared detection. We thus report absorption cross sections and integrated band intensities for isoprene in the 600–6500 cm-1 region. The pressure-broadened (1 atmosphere N2) spectra were recorded at 278, 298, and 323 Kmore » in a 19.94 cm path-length cell at 0.112 cm-1 resolution, using a Bruker IFS 66v/S Fourier transform infrared (FTIR) spectrometer. Composite spectra are derived from a minimum of seven isoprene sample pressures, each at one of three temperatures, and the number densities are normalized to 296 K and 1 atm.« less

  16. Photodetector with absorbing region having resonant periodic absorption between reflectors

    DOE Patents [OSTI]

    Bryan, R.P.; Olbright, G.R.; Brennan, T.M.; Tsao, J.Y.

    1995-02-14

    A photodetector is disclosed that is responsive to a wavelength or wavelengths of interest which have heretofore been unrealized. The photodetector includes a resonant cavity structure bounded by first and second reflectors, the resonant cavity structure being resonant at the wavelength or wavelengths of interest for containing a plurality of standing waves therein. The photodetector further includes a radiation absorbing region disposed within the resonant cavity structure, the radiation absorbing region including a plurality of radiation absorbing layers spaced apart from one another by a distance substantially equal to a distance between antinodes of adjacent ones of the standing waves. Each of radiation absorbing layers is spatially positioned at a location of one of the antinodes of one of the standing waves such that radiation absorption is enhanced. The radiation absorbing layers may be either bulk layers or quantum wells includes a plurality of layers, each of which is comprised of a strained layer of InGaAs. Individual ones of the InGaAs layers are spaced apart from one another by a GaAs barrier layer. 11 figs.

  17. Development of a gas-fired absorption heat pump

    SciTech Connect (OSTI)

    Ohuchi, Y.

    1985-01-01

    A new absorbent-refrigerant pair suitable for heat pump heating and air-cooled cooling has been developed. Water has been selected as the refrigerant, mainly from the viewpoint of high cycle efficiency and safety, while a 1:1 mixture of lithium bromide (LiBr) and zinc chloride (ZnCl/sub 2/) by weight has been chosen as the absorbent in view of its higher solubility and affinity for water. Based on thermodynamic analysis with experimental data on properties, the new absorbent solution will give a heating COP of 1.57 and a cooling COP of 1.00 as gross values of double-effect absorption cycles, including a boiler efficiency of 80%. As a result of an experimental investigation on corrosiveness and corrosion inhibitors, promising equipment materials and inhibitors have been discovered. Prototypical units of 3.5kw (1-ton) and 35kw (10-ton) have been installed and are undergoing demonstration testing in the laboratory.

  18. Simulation of Absorption Systems in Flexible and Modular Form

    Energy Science and Technology Software Center (OSTI)

    1994-09-23

    The computer code has been developed for simulation of absorption systems at steady-state in a flexible and modular form, making it possible to investigate various cycle configurations with different working fluids. The code is based on unit subroutines containing the governing equations for the system''s components. When all the equations have been established, a mathematical solver routine is employed to solve them simultaneously. Property subroutines contained in a separate data base serve to provide thermodynamicmore » properties of the working fluids. The code is user-oriented and requires a relatively simple input containing the given operating conditions and the working fluid at each state point. the user conveys to the computer an image of the cycle by specifying the different components and their interconnections. Based on this information, the program calculates the temperature, flowrate, concentration, pressure and vapor fraction at each state point in the system and the heat duty at each unit, from which the coefficient of performance may be determined. A graphical user-interface is provided to facilitate interactive input and study of the output.« less

  19. High power laser heating of low absorption materials

    SciTech Connect (OSTI)

    Olson, K.; Talghader, J.; Ogloza, A.; Thomas, J.

    2014-09-28

    A model is presented and confirmed experimentally that explains the anomalous behavior observed in continuous wave (CW) excitation of thermally isolated optics. Distributed Bragg Reflector (DBR) high reflective optical thin film coatings of HfO? and SiO?were prepared with a very low absorption, about 7 ppm, measured by photothermal common-path interferometry. When illuminated with a 17 kW CW laser for 30 s, the coatings survived peak irradiances of 13 MW/cm, on 500 ?m diameter spot cross sections. The temperature profile of the optical surfaces was measured using a calibrated thermal imaging camera for illuminated spot sizes ranging from 500 ?m to 5 mm; about the same peak temperatures were recorded regardless of spot size. This phenomenon is explained by solving the heat equation for an optic of finite dimensions and taking into account the non-idealities of the experiment. An analytical result is also derived showing the relationship between millisecond pulse to CW laser operation where (1) the heating is proportional to the laser irradiance (W/m) for millisecond pulses, (2) the heating is proportional to the beam radius (W/m) for CW, and (3) the heating is proportional to W/m? tan?(?(t)/m) in the transition region between the two.

  20. Laser absorption spectroscopy system for vaporization process characterization and control

    SciTech Connect (OSTI)

    Galkowski, J.; Hagans, K.

    1993-09-07

    In support of the Lawrence Livermore National Laboratory`s (LLNL`s) Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) Program, a laser atomic absorption spectroscopy (LAS) system has been developed. This multi-laser system is capable of simultaneously measuring the line densities of {sup 238}U ground and metastable states, {sup 235}U ground and metastable states, iron, and ions at up to nine locations within the separator vessel. Supporting enrichment experiments that last over one hundred hours, this laser spectroscopy system is employed to diagnose and optimize separator system performance, control the electron beam vaporizer and metal feed systems, and provide physics data for the validation of computer models. As a tool for spectroscopic research, vapor plume characterization, vapor deposition monitoring, and vaporizer development, LLNL`s LAS laboratory with its six argon-ion-pumped ring dye lasers and recently added Ti:Sapphire and external-cavity diode-lasers has capabilities far beyond the requirements of its primary mission.

  1. Photodetector with absorbing region having resonant periodic absorption between reflectors

    DOE Patents [OSTI]

    Bryan, Robert P. (Boulder, CO); Olbright, Gregory R. (Boulder, CO); Brennan, Thomas M. (Albuquerque, NM); Tsao, Jeffrey Y. (Albuquerque, NM)

    1995-02-14

    A photodetector that is responsive to a wavelength or wavelengths of interest which have heretofore been unrealized. The photodetector includes a resonant cavity structure bounded by first and second reflectors, the resonant cavity structure being resonant at the wavelength or wavelengths of interest for containing a plurality of standing waves therein. The photodetector further includes a radiation absorbing region disposed within the resonant cavity structure, the radiation absorbing region including a plurality of radiation absorbing layers spaced apart from one another by a distance substantially equal to a distance between antinodes of adjacent ones of the standing waves. Each of radiation absorbing layers is spatially positioned at a location of one of the antinodes of one of the standing waves such that radiation absorption is enhanced. The radiation absorbing layers may be either bulk layers or quantum wells includes a plurality of layers, each of which is comprised of a strained layer of InGaAs. Individual ones of the InGaAs layers are spaced apart from one another by a GaAs barrier layer.

  2. Dataset used to improve liquid water absorption models in the microwave

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Turner, David

    2015-12-14

    Two datasets, one a compilation of laboratory data and one a compilation from three field sites, are provided here. These datasets provide measurements of the real and imaginary refractive indices and absorption as a function of cloud temperature. These datasets were used in the development of the new liquid water absorption model that was published in Turner et al. 2015.

  3. Oxygen production by molten alkali metal salts using multiple absorption-desorption cycles

    DOE Patents [OSTI]

    Cassano, Anthony A.

    1985-01-01

    A continuous chemical air separation is performed wherein oxygen is recovered with a molten alkali metal salt oxygen acceptor in a series of absorption zones which are connected to a plurality of desorption zones operated in separate parallel cycles with the absorption zones. A greater recovery of high pressure oxygen is achieved at reduced power requirements and capital costs.

  4. Oxygen production by molten alkali metal salts using multiple absorption-desorption cycles

    DOE Patents [OSTI]

    Cassano, A.A.

    1985-07-02

    A continuous chemical air separation is performed wherein oxygen is recovered with a molten alkali metal salt oxygen acceptor in a series of absorption zones which are connected to a plurality of desorption zones operated in separate parallel cycles with the absorption zones. A greater recovery of high pressure oxygen is achieved at reduced power requirements and capital costs. 3 figs.

  5. An Evaluation of Mesoscale Model Predictions of Down-Valley and Canyon Flows and Their Consequences Using Doppler Lidar Measurements During VTMX 2000

    SciTech Connect (OSTI)

    Fast, Jerome D.; Darby, Lisa S.

    2004-04-01

    A mesoscale model, a Lagrangian particle dispersion model, and extensive Doppler lidar wind measurements during the VTMX 2000 field campaign were used to examine converging flows over the Salt Lake Valley and their effect on vertical mixing of tracers at night and during the morning transition period. The simulated wind components were transformed into radial velocities to make a direct comparison with about 1.3 million Doppler lidar data points and critically evaluate, using correlation coefficients, the spatial variations in the simulated wind fields aloft. The mesoscale model captured reasonably well the general features of the observed circulations including the daytime up-valley flow, the nighttime slope, canyon, and down-valley flows, and the convergence of the flows over the valley. When there were errors in the simulated wind fields, they were usually associated with the timing, structure, or strength of specific flows. Simulated outflows from canyons along the Wasatch Mountains propagated over the valley and converged with the down-valley flow, but the advance and retreat of these simulated flows was often out of phase with the lidar measurements. While the flow reversal during the evening transition period produced rising motions over much of the valley atmosphere in the absence of significant ambient winds, average vertical velocities became close to zero as the down-valley flow developed. Still, vertical velocities between 5 and 15 cm s-1 occurred where down-slope, canyon and down-valley flows converged and vertical velocities greater than 50 cm s-1 were produced by hydraulic jumps at the base of the canyons. The presence of strong ambient winds resulted in smaller average rising motions during the evening transition period and larger average vertical velocities after that. A fraction of the tracer released at the surface was transported up to the height of the surrounding mountains; however, higher concentrations were produced aloft for evenings characterized by well-developed drainage circulations. Simulations with and without vertical motions in the particle model produced large differences in the tracer concentrations at specific locations and times; however, the overall ventilation of the valley atmosphere differed by only 5% or less. Despite the atmospheric stability, turbulence produced by vertical wind shears mixed particles well above the surface stable layer for the particle model simulation without vertical motions.

  6. DIFFUSE MOLECULAR CLOUD DENSITIES FROM UV MEASUREMENTS OF CO ABSORPTION

    SciTech Connect (OSTI)

    Goldsmith, Paul F.

    2013-09-10

    We use UV measurements of interstellar CO toward nearby stars to calculate the density in the diffuse molecular clouds containing the molecules responsible for the observed absorption. Chemical models and recent calculations of the excitation rate coefficients indicate that the regions in which CO is found have hydrogen predominantly in molecular form and that collisional excitation is by collisions with H{sub 2} molecules. We carry out statistical equilibrium calculations using CO-H{sub 2} collision rates to solve for the H{sub 2} density in the observed sources without including effects of radiative trapping. We have assumed kinetic temperatures of 50 K and 100 K, finding this choice to make relatively little difference to the lowest transition. For the sources having T{sup ex}{sub 10} only for which we could determine upper and lower density limits, we find (n(H{sub 2})) = 49 cm{sup -3}. While we can find a consistent density range for a good fraction of the sources having either two or three values of the excitation temperature, there is a suggestion that the higher-J transitions are sampling clouds or regions within diffuse molecular cloud material that have higher densities than the material sampled by the J = 1-0 transition. The assumed kinetic temperature and derived H{sub 2} density are anticorrelated when the J = 2-1 transition data, the J = 3-2 transition data, or both are included. For sources with either two or three values of the excitation temperature, we find average values of the midpoint of the density range that is consistent with all of the observations equal to 68 cm{sup -3} for T{sup k} = 100 K and 92 cm{sup -3} for T{sup k} = 50 K. The data for this set of sources imply that diffuse molecular clouds are characterized by an average thermal pressure between 4600 and 6800 K cm{sup -3}.

  7. Overview of the first Multi-center Airborne Coherent Atmospheric Wind Sensor (MACAWS) experiment: Conversion of a ground-based lidar for airborne applications

    SciTech Connect (OSTI)

    Howell, J.N.; Hardesty, R.M.; Rothermel, J.; Menzies, R.T.

    1996-12-31

    The first Multi-center Airborne Coherent Atmospheric Wind Sensor (MACAWS) field experiment demonstrated an airborne high energy TEA CO{sub 2} Doppler lidar system for measurement of atmospheric wind fields and aerosol structure. The system was deployed on the NASA DC-8 during September 1995 in a series of checkout flights to observe several important atmospheric phenomena, including upper level winds in a Pacific hurricane, marine boundary layer winds, cirrus cloud properties, and land-sea breeze structure. The instrument, with its capability to measure three-dimensional winds and backscatter fields, promises to be a valuable tool for climate and global change, severe weather, and air quality research. In this paper, the authors describe the airborne instrument, assess its performance, discuss future improvements, and show some preliminary results from September experiments.

  8. High Spectral Resolution Infrared and Raman Lidar Observations for the ARM Program: Clear and Cloudy Sky Applications

    SciTech Connect (OSTI)

    Henry Revercomb, David Tobin, Robert Knuteson, Lori Borg, Leslie Moy

    2009-06-17

    This grant began with the development of the Atmospheric Emitted Radiance Interferometer (AERI) for ARM. The AERI has provided highly accurate and reliable observations of downwelling spectral radiance (Knuteson et al. 2004a, 2004b) for application to radiative transfer, remote sensing of boundary layer temperature and water vapor, and cloud characterization. One of the major contributions of the ARM program has been its success in improving radiation calculation capabilities for models and remote sensing that evolved from the multi-year, clear-sky spectral radiance comparisons between AERI radiances and line-by-line calculations (Turner et al. 2004). This effort also spurred us to play a central role in improving the accuracy of water vapor measurements, again helping ARM lead the way in the community (Turner et al. 2003a, Revercomb et al. 2003). In order to add high-altitude downlooking AERI-like observations over the ARM sites, we began the development of an airborne AERI instrument that has become known as the Scanning High-resolution Interferometer Sounder (Scanning-HIS). This instrument has become an integral part of the ARM Unmanned Aerospace Vehicle (ARM-UAV) program. It provides both a cross-track mapping view of the earth and an uplooking view from the 12-15 km altitude of the Scaled Composites Proteus aircraft when flown over the ARM sites for IOPs. It has successfully participated in the first two legs of the grand tour of the ARM sites (SGP and NSA), resulting in a very good comparison with AIRS observations in 2002 and in an especially interesting data set from the arctic during the Mixed-Phase Cloud Experiment (M-PACE) in 2004. More specifically, our major achievements for ARM include 1. Development of the Atmospheric Emitted Radiance Interferometer (AERI) to function like a satellite on the ground for ARM, providing a steady stream of accurately calibrated spectral radiances for Science Team clear sky and cloud applications (Knuteson et al. 2004a), 2. Detailed radiometric calibration and characterization of AERI radiances, with uncertainty estimates established from complete error analyses and proven by inter-comparison tests (Knuteson et al. 2004b), 3. AERI data quality assessment and maintenance over the extended time frames needed to support ARM (Dedecker et al., 2005) 4. Key role in the radiative transfer model improvements from the AERI/LBLRTM QME (Turner et al. 2004) and AERI-ER especially from the SHEBA experiment (Tobin et al. 1999), 5. Contributed scientific and programmatic leadership leading to significant water vapor accuracy improvements and uncertainty assessments for the low to mid troposphere (Turner et al. 2003a, Revercomb et al. 2003), 6. Leadership of the ARM assessment of the accuracy of water vapor observations from radiosondes, Raman Lidar and in situ aircraft observations in the upper troposphere and lower stratosphere (Tobin et al. 2002, Ferrare et al. 2004), 7. New techniques for characterizing clouds from AERI (DeSlover et al. 1999, Turner 2003b, Turner et al. 2003b), 8. Initial design and development of the Scanning-HIS aircraft instrument and application to ARM UAV Program missions (Revercomb et al. 2005), and 9. Coordinated efforts leading to the use of ARM observations as a key validation tool for the high resolution Atmospheric IR Sounder on the NASA Aqua platform (Tobin et al. 2005a) 10. Performed ARM site and global clear sky radiative closure studies that shows closure of top-of-atmosphere flux at the level of ~1 W/m2 (Moy et al 2008 and Section 3 of this appendix) 11. Performed studies to characterize SGP site cirrus cloud property retrievals and assess impacts on computed fluxes and heating rate profiles (Borg et al. 2008 and Section 2 of this appendix).

  9. Light absorption from particulate impurities in snow and ice determined by spectrophotometric analysis of filters

    SciTech Connect (OSTI)

    Grenfell, Thomas C.; Doherty, Sarah J.; Clarke, Antony D.; Warren, Stephen G.

    2011-05-10

    Light absorption by particulate impurities in snow and ice can affect the surface albedo and is important for the climate. The absorption properties of these particles can be determined by collecting and melting snow samples and extracting the particulate material by filtration of the meltwater. This paper describes the optical design and testing of a new instrument to measure the absorption spectrum from 400 to 750 nm wavelength of the particles collected on filters using an ''integrating-sandwich'' configuration. The measured absorption is shown to be unaffected by scattering of light from the deposited particulates. A set of calibration standards is used to derive an upper limit for the concentration of black carbon (BC) in the snow. The wavelength dependence of the absorption spectra from 450 to 600 nm is used to calculate an absorption Angstrom exponent for the aerosol. This exponent is used to estimate the actual BC concentration in the snow samples as well as the relative contributions of BC and non-BC constituents to the absorption of solar radiation integrated over the wavelength band 300 to 750 nm.

  10. Raman Lidar Receives Improvements

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    at the SGP central facility is receiving upgrades to its environmental controls. This ground-based remote sensing instrument uses a laser to measure vertical profiles of water...

  11. ARM Raman Lidar Applications

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Applications - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Fuel Cycle Defense Waste Management Programs Advanced Nuclear

  12. ARM Raman Lidar Development

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Development - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary Power Energy Conversion Efficiency Solar Energy Wind Energy Water Power Supercritical CO2 Geothermal Natural Gas Safety, Security & Resilience of the Energy Infrastructure Energy Storage Nuclear Power & Engineering Grid Modernization Battery Testing Nuclear Fuel Cycle Defense Waste Management Programs Advanced Nuclear

  13. Effect of electron density profile on power absorption of high frequency electromagnetic waves in plasma

    SciTech Connect (OSTI)

    Xi Yanbin; Liu Yue [MOE Key Laboratory of Materials Modification by Laser, Electron, and Ion Beams, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2012-07-15

    Considering different typical electron density profiles, a multi slab approximation model is built up to study the power absorption of broadband (0.75-30 GHz) electromagnetic waves in a partially ionized nonuniform magnetized plasma layer. Based on the model, the power absorption spectra for six cases are numerically calculated and analyzed. It is shown that the absorption strongly depends on the electron density fluctuant profile, the background electron number density, and the collision frequency. A potential optimum profile is also analyzed and studied with some particular parameters.

  14. Transient effects on the performance of a residential solar absorption chiller

    SciTech Connect (OSTI)

    Guertin, J.M.; Wood, B.D.

    1980-01-01

    The transient performance of a commercial residential 3 ton lithium-bromide/water absorption chiller is studied. Emphasis was placed on separating the chiller response from that of the entire test facility so that its transient response could solely be observed and quantified. It was found that the entire system time response and thermal capacitance has a major impact on performance degradation due to transient operation. Isolation of the absorption chiller from system effects showed time to steady state performance to be a linear function of steady state water supply temperatures. These findings summarized in computer algorithms were used to map the integrated performance of a 3 ton absorption chiller.

  15. Guide to Developing Air-Cooled Lithium Bromide (LiBr) Absorption for CHP

    Office of Environmental Management (EM)

    Applications, April 2005 | Department of Energy Developing Air-Cooled Lithium Bromide (LiBr) Absorption for CHP Applications, April 2005 Guide to Developing Air-Cooled Lithium Bromide (LiBr) Absorption for CHP Applications, April 2005 The objective of this paper is to summarize the development status of air-cooled lithium bromide (LiBr)-water absorption chillers to guide future efforts to develop chillers for combined heat and power (CHP) applications in light-commercial buildings. The key

  16. Photovoltaic device with increased light absorption and method for its manufacture

    DOE Patents [OSTI]

    Glatfelter, Troy; Vogeli, Craig; Call, Jon; Hammond, Ginger

    1993-07-20

    A photovoltaic cell having a light-directing optical element integrally formed in an encapsulant layer thereof. The optical element redirects light to increase the internal absorption of light incident on the photovoltaic device.

  17. Cost reductions in absorption chillers. Final report, June 1984-May 1985

    SciTech Connect (OSTI)

    Leigh, R.W.

    1986-05-01

    Absorption chillers have great difficulty competing with the electric-driven compression alternative, due in part to modest operating efficiencies and largely to high first costs. This project is an assessment of the possibility of lowering the costs of absorption chillers dramatically by the use of low material intensity in the design of a new generation of these machines. Breakeven costs for absorption chillers, their heat exchangers and heat exchanger materials were established which will allow commercial success. Polymeric and metallic materials appropriate to particular components and which meet the cost goals were identified. A subset of these materials were tested and ordered by success in tolerating conditions and materials found in absorption chiller applications. Conceptual designs which indicate the practicality of the low material intensity approach were developed. The work reported here indicates that there is a high probability that this apporach will be successful.

  18. Novel CO2 Binding Mechanism Determined via in-situ Absorption Spectroscopy

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    & Theory | Center for Gas SeparationsRelevant to Clean Energy Technologies | Blandine Jerome Novel CO2 Binding Mechanism Determined via in-situ Absorption Spectroscopy & Theory

  19. Femtosecond X-ray Absorption Spectroscopy at a Hard X-ray Free...

    Office of Scientific and Technical Information (OSTI)

    Femtosecond X-ray Absorption Spectroscopy at a Hard X-ray Free Electron Laser: Application to Spin Crossover Dynamics Citation Details In-Document Search Title: Femtosecond X-ray...

  20. United States Department of Energy large commercial absorption chiller development program

    SciTech Connect (OSTI)

    Garland, P.W.; DeVault, R.C.; Zaltash, A.

    1998-11-01

    The US Department of Energy (DOE) is working with partners from the gas cooling industry to improve energy efficiency and US competitiveness by using advanced absorption technologies that eliminate the use of chlorofluorocarbons (CFCs) and hydrochlorofluorocarbons (HCFCs), refrigerants that contribute to ozone depletion and global warming. Absorption cooling uses natural gas as the heat source, which produces much lower NO{sub x} emissions than oil- or coal-generated electricity. Gas-fired chillers also have the advantage of helping reduce peak electrical usage during summer months. To assist industry in developing advanced absorption cooling technologies, DOE sponsors the Large Commercial Chiller Development Program. The goal of the program is to improve chiller cooling efficiency by 30--50% compared with the best currently available absorption systems.

  1. Use Low-Grade Waste Steam to Power Absorption Chillers - Steam Tip Sheet #14

    SciTech Connect (OSTI)

    2012-01-31

    This revised AMO tip sheet on waste steam to power absorption chillers provides how-to advice for improving the system using low-cost, proven practices and technologies.

  2. Enhanced Gas Absorption in the Ionic Liquid 1-n-Hexyl-3-methylimidazol...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Enhanced Gas Absorption in the Ionic Liquid 1-n-Hexyl-3-methylimidazolium Bis(trifluoromethylsulfonyl)amide (hmimTfsub 2N) Confined in Silica Slit Pores: A ...

  3. On-Board Measurement of Ammonia and Nitrous Oxide Using Feedback Absorption

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Laser Spectroscopy Combined with Amplified Resonance and Low Pressure Sampling | Department of Energy Board Measurement of Ammonia and Nitrous Oxide Using Feedback Absorption Laser Spectroscopy Combined with Amplified Resonance and Low Pressure Sampling On-Board Measurement of Ammonia and Nitrous Oxide Using Feedback Absorption Laser Spectroscopy Combined with Amplified Resonance and Low Pressure Sampling A first set of results has found that LASAR and VLPS data in the laboratory closely

  4. Method of determining pH by the alkaline absorption of carbon dioxide

    DOE Patents [OSTI]

    Hobbs, David T. (1867 Lodgepole Ave., N. Augusta, SC 29841)

    1992-01-01

    A method for measuring the concentration of hydroxides in alkaline solutions in a remote location using the tendency of hydroxides to absorb carbon dioxide. The method includes the passing of carbon dioxide over the surface of an alkaline solution in a remote tank before and after measurements of the carbon dioxide solution. A comparison of the measurements yields the absorption fraction from which the hydroxide concentration can be calculated using a correlation of hydroxide or pH to absorption fraction.

  5. Enhanced Absorption in 2D Materials Via Fano- Resonant Photonic Crystals

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect Enhanced Absorption in 2D Materials Via Fano- Resonant Photonic Crystals Citation Details In-Document Search Title: Enhanced Absorption in 2D Materials Via Fano- Resonant Photonic Crystals Authors: Wang, Wenyi [1] ; Klotz, Andrey [1] ; Yang, Yuanmu [1] ; Li, Wei [1] ; Kravchenko, Ivan I [2] ; Briggs, Dayrl P [2] ; Bolotin, Kirill [1] ; Valentine, Jason [1] + Show Author Affiliations Vanderbilt University, Nashville ORNL Publication Date: 2015-01-01 OSTI

  6. Enhanced Gas Absorption in the Ionic Liquid 1-n-Hexyl-3-methylimidazolium

    Office of Scientific and Technical Information (OSTI)

    Bis(trifluoromethylsulfonyl)amide ([hmim][Tf{sub 2}N]) Confined in Silica Slit Pores: A Molecular Simulation Study (Journal Article) | SciTech Connect Journal Article: Enhanced Gas Absorption in the Ionic Liquid 1-n-Hexyl-3-methylimidazolium Bis(trifluoromethylsulfonyl)amide ([hmim][Tf{sub 2}N]) Confined in Silica Slit Pores: A Molecular Simulation Study Citation Details In-Document Search Title: Enhanced Gas Absorption in the Ionic Liquid 1-n-Hexyl-3-methylimidazolium

  7. Investigation of Absorption Properties of Submicron Aerosol in the Troposphere Over West Siberia

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Investigation of Absorption Properties of Submicron Aerosol in the Troposphere Over West Siberia M. V. Panchenko, V. S. Kozlov, and V. P. Shmargunov Institute of Atmospheric Optics Tomsk, Russia Introduction Improving radiative climate models for the cloudless atmosphere depends largely on the correct way to simulate single-scattering albedo of atmospheric aerosol. Solving this problem requires performing detailed experiments on the study of the aerosol absorption characteristics in the

  8. A Technical and Economic Analysis of an Innovative Two-Step Absorption

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    System for Utilizing Low-Temperature Geothermal Resources to Condition Commercial Buildings | Department of Energy A Technical and Economic Analysis of an Innovative Two-Step Absorption System for Utilizing Low-Temperature Geothermal Resources to Condition Commercial Buildings A Technical and Economic Analysis of an Innovative Two-Step Absorption System for Utilizing Low-Temperature Geothermal Resources to Condition Commercial Buildings PDF icon A Technical and Economic Analysis of an

  9. Thermal emission and absorption of radiation in finite inverted-opal photonic crystals

    SciTech Connect (OSTI)

    Florescu, Marian; Stimpson, Andrew J.; Lee, Hwang; Dowling, Jonathan

    2005-09-15

    We study theoretically the optical properties of a finite inverted-opal photonic crystal. The light-matter interaction is strongly affected by the presence of the three-dimensional photonic crystal and the alterations of the light emission and absorption processes can be used to suppress or enhance the thermal emissivity and absorptivity of the dielectric structure. We investigate the influence of the absorption present in the system on the relevant band edge frequencies that control the optical response of the photonic crystal. Our study reveals that the absorption processes cause spectral broadening and shifting of the band edge optical resonances, and determine a strong reduction of the photonic band gap spectral range. Using the angular and spectral dependence of the band edge frequencies for stop bands along different directions, we argue that by matching the blackbody emission spectrum peak with a prescribed maximum of the absorption coefficient, it is possible to achieve an angle-sensitive enhancement of the thermal emission/absorption of radiation. This result opens a way to realize a frequency-sensitive and angle-sensitive photonic crystal absorbers/emitters.

  10. The polarization dependence of ?? absorptionimplications for ?-ray bursts and blazars

    SciTech Connect (OSTI)

    Bttcher, M.

    2014-11-01

    This paper presents an analysis of the dependence of the opacity for high-energy ?-rays to ?? absorption by low-energy photons on the polarization of the ?-ray and target photons. This process has so far only been considered using the polarization-averaged ?? absorption cross section. It is demonstrated that in the case of polarized ?-ray emission, subject to source-intrinsic ?? absorption by polarized target photons, this may lead to a slight overestimation of the ?? opacity by up to ?10% in the case of a perfectly ordered magnetic field. Thus, for realistic astrophysical scenarios with partially ordered magnetic fields, the use of the polarization-averaged ?? cross section is justified for practical purposes, such as estimates of minimum Doppler factors inferred for ?-ray bursts and blazars, based on ?? transparency arguments; this paper quantifies the small error incurred by the unpolarized-radiation approximation. Furthermore, it is shown that polarization-dependent ?? absorption of initially polarized ?-rays can lead to a slight increase in the polarization beyond the spectral break caused by ?? absorption. This amount is distinctly different from the change in polarization expected if the same spectral break were produced by a break in the underlying electron distribution. This may serve as a diagnostic of whether ?? absorption is relevant in sources such as ?-ray bursts and blazars where the ?-ray emission may be intrinsically highly polarized.

  11. Force-controlled absorption in a fully-nonlinear numerical wave tank

    SciTech Connect (OSTI)

    Spinneken, Johannes Christou, Marios; Swan, Chris

    2014-09-01

    An active control methodology for the absorption of water waves in a numerical wave tank is introduced. This methodology is based upon a force-feedback technique which has previously been shown to be very effective in physical wave tanks. Unlike other methods, an a-priori knowledge of the wave conditions in the tank is not required; the absorption controller being designed to automatically respond to a wide range of wave conditions. In comparison to numerical sponge layers, effective wave absorption is achieved on the boundary, thereby minimising the spatial extent of the numerical wave tank. In contrast to the imposition of radiation conditions, the scheme is inherently capable of absorbing irregular waves. Most importantly, simultaneous generation and absorption can be achieved. This is an important advance when considering inclusion of reflective bodies within the numerical wave tank. In designing the absorption controller, an infinite impulse response filter is adopted, thereby eliminating the problem of non-causality in the controller optimisation. Two alternative controllers are considered, both implemented in a fully-nonlinear wave tank based on a multiple-flux boundary element scheme. To simplify the problem under consideration, the present analysis is limited to water waves propagating in a two-dimensional domain. The paper presents an extensive numerical validation which demonstrates the success of the method for a wide range of wave conditions including regular, focused and random waves. The numerical investigation also highlights some of the limitations of the method, particularly in simultaneously generating and absorbing large amplitude or highly-nonlinear waves. The findings of the present numerical study are directly applicable to related fields where optimum absorption is sought; these include physical wavemaking, wave power absorption and a wide range of numerical wave tank schemes.

  12. Refractive index and absorption detector for liquid chromatography based on Fabry-Perot interferometry

    DOE Patents [OSTI]

    Yeung, E.S.; Woodruff, S.D.

    1984-06-19

    A refractive index and absorption detector are disclosed for liquid chromatography. It is based in part on a Fabry-Perot interferometer and is used for the improved detection of refractive index and absorption. It includes a Fabry-Perot interferometer having a normally fixed first partially reflecting mirror and a movable second partially reflecting mirror. A chromatographic flow-cell is positioned between the mirrors along the optical axis of a monochromatic laser beam passing through the interferometer. A means for deriving information about the interference fringes coming out of the interferometer is used with a mini-computer to compute the refractive index of the specimen injected into the flow cell. The minicomputer continuously scans the interferometer for continuous refractive index readings and outputs the continuous results of the scans on a chart recorder. The absorption of the specimen can concurrently be scanned by including a second optical path for an excitation laser which will not interfere with the first laser, but will affect the specimen so that absorption properties can be detected. By first scanning for the refractive index of the specimen, and then immediately adding the excitation laser and subsequently scanning for the refractive index again, the absorption of the specimen can be computed and recorded. 10 figs.

  13. Analysis of CASES-99 Lidar and Turbulence Data in Support of Wind Turbine Effects: April 1, 2001 to Januay 31, 2003

    SciTech Connect (OSTI)

    Banta, R. M.

    2003-06-01

    The nocturnal low-level jet (LLJ) of the Great Plains of the central United States has been identified as a promising source of high-momentum wind flow for wind energy. The acceleration of the winds after sunset above the surface produces a jet profile in the wind velocity, with maximum speeds that often exceed 10 m s-1 or more at heights near 100 m or more. These high wind speeds are advantageous for wind energy generation. The high speeds aloft, however, also produce a region of high shear between the LLJ and the earth's surface, where the nocturnal flow is often calm or nearly so. This shear zone below the LLJ generates atmospheric waves and turbulence that can cause strong vibration in the turbine rotors. It has been suggested that these vibrations contribute to premature failures in large wind turbines, which, of course, would be a considerable disadvantage for wind energy applications. In October 1999, a field project called the Cooperative Atmosphere-Surface Exchange Study 1999 campaign, or CASES-99, was conducted in southeastern Kansas to study the nocturnal stable boundary layer. One of the instruments deployed during CASES-99 was the High-Resolution Doppler Lidar, a new scanning, remote-sensing, wind-mapping instrument.

  14. Mode conversion and absorption of fast waves at high ion cyclotron harmonics in inhomogeneous magnetic fields

    SciTech Connect (OSTI)

    Cho, Suwon; Kwak, Jong-Gu

    2014-04-15

    The propagation and absorption of high harmonic fast waves is of interest for non-inductive current drives in fusion experiments. The fast wave can be coupled with the ion Bernstein wave that propagates in the high magnetic field side of an ion cyclotron harmonic resonance layer. This coupling and the absorption are analyzed using the hot plasma dispersion relation and a wave equation that was converted from an approximate dispersion relation for the case where λ{sub i}=k{sub ⊥}{sup 2}ρ{sub i}{sup 2}/2≳1 (where k{sub ⊥} is the perpendicular wave number and ρ{sub i} is the ion Larmor radius). It is found that both reflection and conversion may occur near the harmonic resonance layer but that they decrease rapidly, giving rise to a sharp increase in the absorption as the parallel wave number increases.

  15. On the dynamic and static manifestation of molecular absorption in thin films probed by a microcantilever

    SciTech Connect (OSTI)

    Finot, Eric; Fabre, Arnaud; Passian, Ali; Thundat, Thomas

    2014-03-01

    Mechanical resonators shaped like microcantilevers have been demonstrated as a platform for very sensitive detection of chemical and biological analytes. However, its use as an analytical tool will require fundamental understanding of the molecular absorption-induced effects in the static and dynamic sensor response. The effect of absorption-induced surface stress on the microcantilever response is here investigated using palladium hydride formation. It is shown that the resonance and deformation states of the cantilever monitored simultaneously exhibit excellent correlation with the phase of the hydride formation. However, the associated frequency shifts and quasistatic bending are observed to be independent during solid solution phase. Importantly, absorption-induced changes in the elastic parameters of the palladium film are found to play a dominant role in the static and dynamic response. The presented results help in discerning the parameters that control the cantilever response as well as the relationships between these parameters.

  16. Using laser absorption spectroscopy to monitor composition and physical properties of metal vapors

    SciTech Connect (OSTI)

    Berzins, L.V.

    1993-09-03

    The Atomic Vapor Laser Isotope Separation (AVLIS) program has been using laser absorption spectroscopy to monitor vapor densities for over 15 years. Laser absorption spectroscopy has proven itself to be an accurate and reliable method to monitor both density and composition. During this time the diagnostic has moved from a research tool toward a robust component of a process control system. The hardware used for this diagnostic is discussed elsewhere at this symposium. This paper describes how the laser absorption spectroscopy diagnostic is used as a component of a process control system as well as supplying detailed measurements on vapor densities, composition, flow velocity, internal and kinetic temperatures, and constituent distributions. Examples will be drawn from the uranium AVLIS program. In addition potential applications such as composition control in the production of metal matrix composites or aircraft alloys will be discussed.

  17. An improved absorption generator for solar-thermal powered heat pumps. Part 2: Energy and economics

    SciTech Connect (OSTI)

    Fineblum, S.

    1997-12-31

    Solar heated absorption chiller installations have been very expensive for their rating. To enhance collector thermal efficiency the liquid flowing within the collectors must be kept as cool as possible. However, there is also a need to operate the absorption reported earlier. The compromise usually results in poor collector efficiency as well as a relatively poor specific chiller effect. The proposed vortex generator permits a heat pump to operate efficiently with relatively low temperature solar heated fluid (70--80 C). As a result, the collectors are cooler and more efficient. As noted in Part 1, the specific heat pumping capacity is about 27% greater than conventional systems operating at the same reduced generator temperatures. Therefore, a smaller, less expensive chiller is required. The reduced investment in solar arrays and absorption chillers is estimated along with a range of paybacks.

  18. Dynamic performance testing of prototype 3 ton air-cooled carrier absorption chiller

    SciTech Connect (OSTI)

    Borst, R.R.; Wood, B.D.

    1985-05-01

    The performance of a prototype 3 ton cooling capacity air-cooled lithium bromide/water absorption chiller was tested using an absorption chiller test facility which was modified to expand its testing capabilities to include air-cooled chillers in addition to water-cooled chillers. Temperatures of the three externally supplied fluid loops: hot water, chilled water, and cooling air, were varied in order to determine the effects this would have on the two principal measures of chiller performance: cooling capacity and thermal coefficient of performance (COP). A number of interrelated factors were identified as contributing to less than expected performance. For comparison, experimental correlations of other investigators for this and other similar absorption chillers are presented. These have been plotted as both contour and three-dimensional performance maps in order to more clearly show the functional dependence of the chiller performance on the fluid loop temperatures.

  19. Anisotropy of two-photon absorption and free-carrier effect in nonpolar GaN

    SciTech Connect (OSTI)

    Fang, Yu; Zhou, Feng; Yang, Junyi; Wu, Xingzhi; Xiao, Zhengguo; Li, Zhongguo; Song, Yinglin

    2015-03-30

    We reported a systematic study about the anisotropic optical nonlinearities in bulk m-plane and a-plane GaN crystals by Z-scan and pump-probe with phase object methods under picosecond at 532?nm. The two-photon absorption coefficient, which was measured as a function of polarization angle, exhibited oscillation curves with a period of ?/2, indicating a highly polarized optical third-order nonlinearity in both nonpolar GaN samples. Furthermore, free-carrier absorption revealed stronger hole-related absorption for E?c than for E//c probe polarization. In contrast, free-carrier refraction was found almost isotropic due to electron-related refraction in the isotropic conduction bands.

  20. LiCl Dehumidifier LiBr absorption chiller hybrid air conditioning system with energy recovery

    DOE Patents [OSTI]

    Ko, Suk M. (Huntsville, AL)

    1980-01-01

    This invention relates to a hybrid air conditioning system that combines a solar powered LiCl dehumidifier with a LiBr absorption chiller. The desiccant dehumidifier removes the latent load by absorbing moisture from the air, and the sensible load is removed by the absorption chiller. The desiccant dehumidifier is coupled to a regenerator and the desiccant in the regenerator is heated by solar heated hot water to drive the moisture therefrom before being fed back to the dehumidifier. The heat of vaporization expended in the desiccant regenerator is recovered and used to partially preheat the driving fluid of the absorption chiller, thus substantially improving the overall COP of the hybrid system.

  1. An experimental investigation of the mass-transfer mechanisms in sulfur dioxide absorption in lime solutions

    SciTech Connect (OSTI)

    Markussen, J.M.

    1991-04-01

    The experiments were performed at gas temperatures from 24 to 114C using a wetted-wall column apparatus with SO{sub 2} concentrations ranging from 1800 to 7350 ppM, calcium concentrations of 2.82 {times} 10{sup {minus}6} to 1. 25 {times} 10{sup {minus}5} gmol/cm{sup 3}, and column heights of 14 to 29 cm. Inlet SO{sub 2} content had a significant effect on rate of SO{sub 2} absorption, with the average absorption flux increasing with increasing SO{sub 2} gas concentration. Increasing gas temperature did not significantly affect the rate of SO{sub 2} absorption. Presence of lime in solution enhanced the average SO{sub 2} absorption flux and appeared to maintain the SO{sub 2} absorption capacity of the liquid, thereby negating the effect of decreasing SO{sub 2} solubility in water with increasing temperature. Slight increases in both the system`s gas-phase resistances and enhancement factors were observed with increasing gas temperature. Under the conditions studied, the mass-transfer resistance in the SO{sub 2}-lime solution system was predominantly liquid-phase controlled, with observed gas-phase resistances ranging up to 42% of total. Comparison to literature shows that the system mass-transfer mechanism can be dominated by either the gas-phase resistance or the liquid-phase resistance, depending upon the gas-liquid contact times. Thus, results support the need to incorporate both gas- and liquid-phase mass-transfer resistances when modeling the absorption of SO{sub 2} in lime solutions and lime slurries, such as that occurring in the constant rate drying stage of the spray drying flue gas desulfurization process.

  2. An experimental investigation of the mass-transfer mechanisms in sulfur dioxide absorption in lime solutions

    SciTech Connect (OSTI)

    Markussen, J.M.

    1991-04-01

    The experiments were performed at gas temperatures from 24 to 114C using a wetted-wall column apparatus with SO[sub 2] concentrations ranging from 1800 to 7350 ppM, calcium concentrations of 2.82 [times] 10[sup [minus]6] to 1. 25 [times] 10[sup [minus]5] gmol/cm[sup 3], and column heights of 14 to 29 cm. Inlet SO[sub 2] content had a significant effect on rate of SO[sub 2] absorption, with the average absorption flux increasing with increasing SO[sub 2] gas concentration. Increasing gas temperature did not significantly affect the rate of SO[sub 2] absorption. Presence of lime in solution enhanced the average SO[sub 2] absorption flux and appeared to maintain the SO[sub 2] absorption capacity of the liquid, thereby negating the effect of decreasing SO[sub 2] solubility in water with increasing temperature. Slight increases in both the system's gas-phase resistances and enhancement factors were observed with increasing gas temperature. Under the conditions studied, the mass-transfer resistance in the SO[sub 2]-lime solution system was predominantly liquid-phase controlled, with observed gas-phase resistances ranging up to 42% of total. Comparison to literature shows that the system mass-transfer mechanism can be dominated by either the gas-phase resistance or the liquid-phase resistance, depending upon the gas-liquid contact times. Thus, results support the need to incorporate both gas- and liquid-phase mass-transfer resistances when modeling the absorption of SO[sub 2] in lime solutions and lime slurries, such as that occurring in the constant rate drying stage of the spray drying flue gas desulfurization process.

  3. Effect of vitrification temperature upon the solar average absorptance properties of Pyromark Series 2500 black paint

    SciTech Connect (OSTI)

    Nelson, C.; Mahoney, A.R.

    1986-06-01

    A significant drop in production efficiency has occurred over time at the Solar One facility at Barstow, California, primarily as a result of the degradation of the Pyromark Series 2500 black paint used as the absorptive coating on the receiver panels. As part of the investigation of the problem, the solar-averaged adsorptance properties of the paint were determined as a function of vitrification temperature, since it is known that a significant amount of the panel surface area at Solar One was vitrified at temperatures below those recommended by the paint manufacturer (540/sup 0/C, 1000/sup 0/F). Painted samples initially vitrified at 230/sup 0/C (450/sup 0/F), 315/sup 0/C (600/sup 0/F), 371/sup 0/C (700/sup 0/F), and 480/sup 0/C (900/sup 0/F) exhibited significantly lower solar-averaged absorptance values (0.02 absorptance units) compared to samples vitrified at 540/sup 0/C (1000/sup 0/F). Thus, Solar One began its service life below optimal levels. After 140 h of thermal aging at 370/sup 0/C (700/sup 0/F) and 540/sup 0/C (1000/sup 0/F), all samples regardless of their initial vitrification temperatures, attained the same solar-averaged absorptance value (..cap alpha../sub s/ = 0.973). Therefore, both the long-term low-temperature vitrification and the short-term high-temperature vitrification can be used to obtain optimal or near-optimal absorptance of solar flux. Futher thermal aging of vitrified samples did not result in paint degradation, clearly indicating that high solar flux is required to produce this phenomenon. The panels at Solar One never achieved optimal absorptance because their exposure to high solar flux negated the effect of long-term low-temperature vitrification during operation. On future central receiver projects, every effort should be made to properly vitrify the Pyromark coating before its exposure to high flux conditions.

  4. Systems having optical absorption layer for mid and long wave infrared and methods for making the same

    DOE Patents [OSTI]

    Kuzmenko, Paul J

    2013-10-01

    An optical system according to one embodiment includes a substrate; and an optical absorption layer coupled to the substrate, wherein the optical absorption layer comprises a layer of diamond-like carbon, wherein the optical absorption layer absorbs at least 50% of mid wave infrared light (3-5 .mu.m wavelength) and at least 50% of long wave infrared light (8-13 .mu.m wavelength). A method for applying an optical absorption layer to an optical system according to another embodiment includes depositing a layer of diamond-like carbon of an optical absorption layer above a substrate using plasma enhanced chemical vapor deposition, wherein the optical absorption layer absorbs at least 50% of mid wave infrared light (3-5 .mu.m wavelength) and at least 50% of long wave infrared light (8-13 .mu.m wavelength). Additional systems and methods are also presented.

  5. Method for measuring changes in light absorption of highly scattering media

    DOE Patents [OSTI]

    Bigio, Irving J. (Los Alamos, NM); Johnson, Tamara M. (Los Alamos, NM); Mourant, Judith R. (Los Alamos, NM)

    2002-01-01

    The noninvasive measurement of variations in absorption that are due to changes in concentrations of biochemically relevant compounds in tissue is important in many clinical settings. One problem with such measurements is that the pathlength traveled by the collected light through the tissue depends on the scattering properties of the tissue. It is demonstrated, using both Monte Carlo simulations and experimental measurements, that for an appropriate separation between light-delivery and light-collection fibers, the pathlength of the collected photons is insensitive to scattering parameters for the range of parameters typically found in tissue. This is important for developing rapid, noninvasive, inexpensive, and accurate methods for measuring absorption changes in tissue.

  6. Non-degenerate two-photon absorption in silicon waveguides. Analytical and experimental study

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Zhang, Yanbing; Husko, Chad; Lefrancois, Simon; Rey, Isabella H.; Krauss, Thomas F.; Schröder, Jochen; Eggleton, Benjamin J.

    2015-06-22

    We theoretically and experimentally investigate the nonlinear evolution of two optical pulses in a silicon waveguide. We provide an analytic solution for the weak probe wave undergoing non-degenerate two-photon absorption (TPA) from the strong pump. At larger pump intensities, we employ a numerical solution to study the interplay between TPA and photo-generated free carriers. We develop a simple and powerful approach to extract and separate out the distinct loss contributions of TPA and free-carrier absorption from readily available experimental data. Our analysis accounts accurately for experimental results in silicon photonic crystal waveguides.

  7. Optical absorption in B{sub 13} cluster: A time-dependent density functional approach

    SciTech Connect (OSTI)

    Shinde, Ravindra; Tayade, Meenakshi

    2013-02-05

    The linear optical absorption spectra of three isomers of planar boron cluster B{sub 13} are calculated using time-dependent spin-polarized density functional approach. The geometries of these cluster are optimized at the B3LYP/6-311+G* level of theory. Even though the isomers are almost degenerate, the calculated spectra are quite different, indicating a strong structure-property relationship. Therefore, these computed spectra can be used in the photo-absorption experiments to distinguish between different isomers of a cluster.

  8. Enhancement of near-infrared absorption in graphene with metal gratings

    SciTech Connect (OSTI)

    Zhao, B.; Zhang, Z. M., E-mail: zhuomin.zhang@me.gatech.edu [G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Zhao, J. M. [G.W. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); School of Energy Science and Engineering, Harbin Institute of Technology, Harbin (China)

    2014-07-21

    Graphene has been demonstrated as a good candidate for ultrafast optoelectronic devices. However, graphene is essentially transparent in the visible and near infrared with an absorptivity of 2.3%, which has largely limited its application in photon detection. This Letter demonstrates that the absorptance in a monatomic graphene layer can be greatly enhanced to nearly 70%, thanks to the localized strong electric field resulting from magnetic resonances in deep metal gratings. Furthermore, the resonance frequency is essentially not affected by the additional graphene layer. The method presented here may benefit the design of next-generation graphene-based optical and optoelectronic devices.

  9. Enhanced anomalous photo-absorption from TiO{sub 2} nanostructures

    SciTech Connect (OSTI)

    Solanki, Vanaraj; Majumder, Subrata; Mishra, Indrani; Varma, Shikha; Dash, P.; Singh, C.; Kanjilal, D.

    2014-03-28

    Two dimensional nanostructures have been created on the rutile TiO{sub 2} (110) surfaces via ion irradiation technique. Enhanced anomalous photo- absorption response is displayed, where nanostructures of 15?nm diameter with 0.5?nm height, and not the smaller nanostructures with larger surface area, delineate highest absorbance. Comprehensive investigations of oxygen vacancy states, on ion- irradiated surfaces, display a remarkable result that the number of vacancies saturates for higher fluences. A competition between the number of vacancy sites on the nanostructure in conjunction with its size is responsible for the observed anomalous photo-absorption.

  10. Electronic structure of titania aerogels: Soft x-ray absorption study

    Office of Scientific and Technical Information (OSTI)

    (Journal Article) | SciTech Connect Journal Article: Electronic structure of titania aerogels: Soft x-ray absorption study Citation Details In-Document Search Title: Electronic structure of titania aerogels: Soft x-ray absorption study Authors: Kucheyev, S O ; van Buuren, T ; Baumann, T F ; Satcher, Jr, J H ; Willey, T M ; Meulenberg, R W ; Felter, T E ; Poco, J F ; Gammon, S A ; Terminello, L J Publication Date: 2004-02-12 OSTI Identifier: 926419 Report Number(s): UCRL-JRNL-202402 DOE

  11. Bench-Scale Development of a Hot Carbonate Absorption Process with

    Office of Scientific and Technical Information (OSTI)

    Crystallization-Enabled High-Pressure Stripping for Post-Combustion CO{sub 2} Capture (Technical Report) | SciTech Connect High-Pressure Stripping for Post-Combustion CO{sub 2} Capture Citation Details In-Document Search Title: Bench-Scale Development of a Hot Carbonate Absorption Process with Crystallization-Enabled High-Pressure Stripping for Post-Combustion CO{sub 2} Capture A novel Hot Carbonate Absorption Process with Crystallization-Enabled High-Pressure Stripping (Hot-CAP) has been

  12. Inverse Design of High-Absorption Thin-Film Photovoltaic Materials

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Center for Inverse Design scientists identified some potential Cu-V-VI thin-film photovoltaic (PV) absorber materials that have stronger solar absorption than CuInSe 2 -one of the most- studied thin-film PV absorber materials-and revealed a general structure-property (absorption) relationship. Significance and Impact The strongly absorbing materials that were identified can be incorporated into solar cells in very thin films. Also, they avoid using a low-Earth-abundant element such as In

  13. Gas cell for in situ soft X-ray transmission-absorption spectroscopy of

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    materials | Center for Gas SeparationsRelevant to Clean Energy Technologies | Blandine Jerome cell for in situ soft X-ray transmission-absorption spectroscopy of materials Previous Next List W. S. Drisdell and J. B. Kortright, Rev. Sci. Instrum. 85, 074103 (2014) DOI: 10.1063/1.4890816 1.4890816.figures.online.f1 Abstract: A simple gas cell design, constructed primarily from commercially available components, enables in situ soft X-ray transmission-absorption spectroscopy of materials in

  14. Approaching total absorption at near infrared in a large area monolayer graphene by critical coupling

    SciTech Connect (OSTI)

    Liu, Yonghao; Chadha, Arvinder; Zhao, Deyin; Shuai, Yichen; Menon, Laxmy; Yang, Hongjun; Zhou, Weidong; Piper, Jessica R.; Fan, Shanhui; Jia, Yichen; Xia, Fengnian; Ma, Zhenqiang

    2014-11-03

    We demonstrate experimentally close to total absorption in monolayer graphene based on critical coupling with guided resonances in transfer printed photonic crystal Fano resonance filters at near infrared. Measured peak absorptions of 35% and 85% were obtained from cavity coupled monolayer graphene for the structures without and with back reflectors, respectively. These measured values agree very well with the theoretical values predicted with the coupled mode theory based critical coupling design. Such strong light-matter interactions can lead to extremely compact and high performance photonic devices based on large area monolayer graphene and other twodimensional materials.

  15. Apparatus and method for measurement of weak optical absorptions by thermally induced laser pulsing

    DOE Patents [OSTI]

    Cremers, D.A.; Keller, R.A.

    1985-10-01

    The thermal lensing phenomenon is used as the basis for measurement of weak optical absorptions when a cell containing the sample to be investigated is inserted into a normally continuous-wave operation laser-pumped dye laser cavity for which the output coupler is deliberately tilted relative to intracavity circulating laser light, and pulsed laser output ensues, the pulsewidth of which can be related to the sample absorptivity by a simple algorithm or calibration curve. A minimum detection limit of less than 10[sup [minus]5] cm[sup [minus]1] has been demonstrated using this technique. 6 figs.

  16. Apparatus and method for measurement of weak optical absorptions by thermally induced laser pulsing

    DOE Patents [OSTI]

    Cremers, D.A.; Keller, R.A.

    1982-06-08

    The thermal lensing phenomenon is used as the basis for measurement of weak optical absorptions when a cell containing the sample to be investigated is inserted into a normally continuous-wave operation laser-pumped dye laser cavity for which the output coupler is deliberately tilted relative to intracavity circulating laser light, and pulsed laser output ensues, the pulsewidth of which can be rlated to the sample absorptivity by a simple algorithm or calibration curve. A minimum detection limit of less than 10/sup -5/ cm/sup -1/ has been demonstrated using this technique.

  17. Optimizing and calibrating a mode-mismatched thermal lens experiment for low absorption measurement

    SciTech Connect (OSTI)

    Marcano, Aristides; Cabrera, Humberto; Guerra, Mayamaru; Cruz, Renato A.; Jacinto, Carlos; Catunda, Tomaz

    2006-07-15

    We describe a calibrated two-beam mode-mismatched thermal lens experiment aimed at determination of the absorption coefficient and the photothermal parameters of a nearly transparent material. The use of a collimated probe beam in the presence of a focused excitation beam optimizes the thermal lens experiment. The signal becomes independent from the Rayleigh parameters and waist positions of the beams. We apply this method to determine the absolute value of the thermal diffusivity and absorption coefficient of distilled water at 533 nm.

  18. Data processing of absorption spectra from photoionized plasma experiments at Z

    SciTech Connect (OSTI)

    Hall, I. M.; Durmaz, T.; Mancini, R. C.; Bailey, J. E.; Rochau, G. A.

    2010-10-15

    We discuss the processing of x-ray absorption spectra from photoionized plasma experiments at Z. The data was recorded with an imaging spectrometer equipped with two elliptically bent potassium acid phthalate (KAP) crystals. Both time-integrated and time-resolved data were recorded. In both cases, the goal is to obtain the transmission spectra for quantitative analysis of plasma conditions.

  19. Integrated three-dimensional photonic nanostructures for achieving near-unity solar absorption and superhydrophobicity

    SciTech Connect (OSTI)

    Kuang, Ping; Lin, Shawn-Yu; Hsieh, Mei-Li

    2015-06-07

    In this paper, we proposed and realized 3D photonic nanostructures consisting of ultra-thin graded index antireflective coatings (ARCs) and woodpile photonic crystals. The use of the integrated ARC and photonic crystal structure can achieve broadband, broad-angle near unity solar absorption. The amorphous silicon based photonic nanostructure experimentally shows an average absorption of ∼95% for λ = 400–620 nm over a wide angular acceptance of θ = 0°–60°. Theoretical studies show that a Gallium Arsenide (GaAs) based structure can achieve an average absorption of >95% for λ = 400–870 nm. Furthermore, the use of the slanted SiO{sub 2} nanorod ARC surface layer by glancing angle deposition exhibits Cassie-Baxter state wetting, and superhydrophobic surface is obtained with highest water contact angle θ{sub CB} ∼ 153°. These properties are fundamentally important for achieving maximum solar absorption and surface self-cleaning in thin film solar cell applications.

  20. Absorptivity of semiconductors used in the production of solar cell panels

    SciTech Connect (OSTI)

    Kosyachenko, L. A. Grushko, E. V.; Mikityuk, T. I.

    2012-04-15

    The dependence of the absorptivity of semiconductors on the thickness of the absorbing layer is studied for crystalline silicon (c-Si), amorphous silicon (a-Si), cadmium telluride (CdTe), copper indium diselenide (CuInSe{sub 2}, CIS), and copper gallium diselenide (CuGaSe{sub 2}, CGS). The calculations are performed with consideration for the spectral distribution of AM1.5 standard solar radiation and the absorption coefficients of the materials. It is shown that, in the region of wavelengths {lambda} = {lambda}{sub g} = hc/E{sub g}, almost total absorption of the photons in AM1.5 solar radiation is attained in c-Si at the thickness d = 7-8 mm, in a-Si at d = 30-60 {mu}m, in CdTe at d = 20-30 {mu}m, and in CIS and CGS at d = 3-4 {mu}m. The results differ from previously reported data for these materials (especially for c-Si). In previous publications, the thickness needed for the semiconductor to absorb solar radiation completely was identified with the effective light penetration depth at a certain wavelength in the region of fundamental absorption for the semiconductor.

  1. Use of radial symmetry for the calculation of cylindrical absorption coefficients and optimal capillary loadings

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Khalifah, Peter

    2015-02-01

    The problem of numerically evaluating absorption correction factors for cylindrical samples has been revisited using a treatment that fully takes advantage of the sample symmetry. It is shown that the path lengths for all points within the sample at all possible diffraction angles can be trivially determined once the angle-dependent distance distribution for a single line of points is calculated. This provides advantages in both computational efficiency and in gaining an intuitive understanding of the effects of absorption on diffraction data. A matrix of absorption coefficients calculated for µR products between 0 and 20 for diffraction angles θD of 0°more » to 90° were used to examine the influence of (1) capillary diameter and of (2) sample density on the overall scattered intensity as a function of diffraction angle, where µ is the linear absorption coefficient for the sample and R is the capillary radius. Based on this analysis, the optimal sample loading for a capillary experiment to maximize diffraction at angles of 0 – 50° is in general expected to be achieved when the maximum radius capillary compatible with the beam is used, and when the sample density is adjusted to be 3/(4µR) of its original density.« less

  2. The Correlation of Coupled Heat and Mass Transfer Experimental Data for Vertical Falling Film Absorption

    SciTech Connect (OSTI)

    Keyhani, M.; Miller, W.A.

    1999-11-14

    Absorption chillers are gaining global acceptance as quality comfort cooling systems. These machines are the central chilling plants and the supply for cotnfort cooling for many large commercial buildings. Virtually all absorption chillers use lithium bromide (LiBr) and water as the absorption fluids. Water is the refrigerant. Research has shown LiBr to he one of the best absorption working fluids because it has a high affinity for water, releases water vapor at relatively low temperatures, and has a boiling point much higher than that of water. The heart of the chiller is the absorber, where a process of simultaneous heat and mass transfer occurs as the refrigerant water vapor is absorbed into a falling film of aqueous LiBr. The more water vapor absorbed into the falling film, the larger the chiller?s capacity for supporting comfort cooling. Improving the performance of the absorber leads directly to efficiency gains for the chiller. The design of an absorber is very empirical and requires experimental data. Yet design data and correlations are sparse in the open literature. The experimental data available to date have been derived at LiBr concentrations ranging from 0.30 to 0.60 mass fraction. No literature data are readily available for the design operating conditions of 0.62 and 0.64 mass fraction of LiBr and absorber pressures of 0.7 and 1.0 kPa.

  3. Cycle simulation of the low-temperature triple-effect absorption chiller with vapor compression unit

    SciTech Connect (OSTI)

    Kim, J.S.; Lee, H.

    1999-07-01

    The construction of a triple-effect absorption chiller machine using the lithium bromide-water solution as a working fluid is strongly limited by corrosion problems caused by the high generator temperature. In this work, three new cycles having the additional vapor compression units were suggested in order to lower the generator temperature of a triple-effect absorption chiller. Each new cycle has one compressor located at the different position which was used to elevate the pressure of the refrigerant vapor. Computer simulations were carried out in order to examine both the basic triple-effect cycle and three new cycles. All types of triple-effect absorption chiller cycles were found to be able to lower the temperature of high-temperature generator to the more favorable operation range. The COPs of three cycles calculated by considering the additional compressor works showed a small level of decrease or increase compared with that of the basic triple-effect cycle. Consequently, a low-temperature triple-effect absorption chiller can be possibly constructed by adapting one of three new cycles. A great advantage of these new cycles over the basic one is that the conventionally used lithium bromide-water solution can be successfully used as a working fluid without the danger of corrosion.

  4. Enhanced heat transfer tubes for film absorbers of absorption chiller/heater

    SciTech Connect (OSTI)

    Sasaki, Naoe; Nosetani, Tadashi; Furukawa, Masahiro; Kaneko, Toshiyuki

    1995-12-31

    Absorption chiller/heaters using non-CFC refrigerants are attracting attention as environmentally friendly energy systems. As the refrigerant/absorbent pair, the water/lithium bromide aqueous solution pair is preferably used for most absorption chiller/heaters in Japan. Absorption chiller/heaters, mainly used as water chillers and air-conditioners, are commercially available at least for unit cooling capacities above 60 kW. In absorption chiller/heaters, the absorber must be made compact, because the absorber has the largest heat transfer area of the four primary heat exchangers in the system: the evaporator, absorber, regenerator and condenser. Although a great amount of information is available on the evaporator and condenser, the same type of information concerning the absorber is lacking. This paper introduces two kinds of double fluted tubes called Arm tubs and Floral tubes for film absorbers. Arm tubes are manufactured using a two-pass drawbench process, while Floral tubes are made using a single pass drawbench process. The experiments using a lithium bromide aqueous solution with the addition of 250 ppm n-octyl alcohol as the surfactant showed that Arm tubes and Floral tubes had about 40% higher heat transfer performance than plain tubes. Therefore, Floral tubes are expected to realize a high performance at low cost. Furthermore, the optimization of the number of grooves on the outside of the tubes is also described here.

  5. Ab initio calculation of the electronic absorption spectrum of liquid water

    SciTech Connect (OSTI)

    Martiniano, Hugo F. M. C.; Galamba, Nuno; Cabral, Benedito J. Costa; Departamento de Qumica e Bioqumica, Faculdade de Cincias, Universidade de Lisboa, 1749-016 Lisboa; Instituto de Fsica da Universidade de So Paulo, CP 66318, 05314-970 So Paulo, SP

    2014-04-28

    The electronic absorption spectrum of liquid water was investigated by coupling a one-body energy decomposition scheme to configurations generated by classical and Born-Oppenheimer Molecular Dynamics (BOMD). A Frenkel exciton Hamiltonian formalism was adopted and the excitation energies in the liquid phase were calculated with the equation of motion coupled cluster with single and double excitations method. Molecular dynamics configurations were generated by different approaches. Classical MD were carried out with the TIP4P-Ew and AMOEBA force fields. The BLYP and BLYP-D3 exchange-correlation functionals were used in BOMD. Theoretical and experimental results for the electronic absorption spectrum of liquid water are in good agreement. Emphasis is placed on the relationship between the structure of liquid water predicted by the different models and the electronic absorption spectrum. The theoretical gas to liquid phase blue-shift of the peak positions of the electronic absorption spectrum is in good agreement with experiment. The overall shift is determined by a competition between the OH stretching of the water monomer in liquid water that leads to a red-shift and polarization effects that induce a blue-shift. The results illustrate the importance of coupling many-body energy decomposition schemes to molecular dynamics configurations to carry out ab initio calculations of the electronic properties in liquid phase.

  6. Structural stability of 1100{degree}C heated Pd/k during absorption cycling in protium

    SciTech Connect (OSTI)

    Fisher, I.A.

    1993-03-12

    Pd/k is a hydride forming packing material which is used in the Thermal Cycling Absorption Process (TCAP). Palladium is supported on kieselguhr to create a packing material which will provide adequate void space to prevent excessive pressure drops and flow restrictions. The use of unsupported palladium would result in blockage of columns and clogging of filters due to the small particle size of unsupported palladium hydride powder. During pilot scale demonstrations, it was noted that the Pd/k packing material had degraded causing severe flow restrictions within the TCAP column. A solution to the problem involved the heating of Pd/k at 1,110{degree}C to strengthen the packing material, and render it more resistant to breakdown. The 1, 100{degree}C heated Pd/k has been shown to be more resistant to mechanical breakdown than the Pd/k prior to heat treatment. Two primary modes of Pd/k particle degradation have been identified: mechanical breakdown caused by particle fluidization and degradation caused by absorption/desorption cycling. Absorption/desorption cycling causes the palladium particles within the packing to expanded and contract upon formation and decomposition of the hydride, respectively. This expansion and contraction causes large localized stresses within the packing material, which if these stresses can not be accommodated within the packing will cause the material to crack and degrade. The purpose of this report is to document the results of the absorption/desorption cycling of 1,100{degree}C heated Pd/k and compare these results to the results obtained from the absorption/desorption cycling of Pd/k which had not been heated at 1, 100{degree}C.

  7. Light absorption and electrical transport in Si:O alloys for photovoltaics

    SciTech Connect (OSTI)

    Mirabella, S.; Crupi, I.; Miritello, M.; Simone, F.; Di Martino, G.; Di Stefano, M. A.; Di Marco, S.; Priolo, F.

    2010-11-15

    Thin films (100-500 nm) of the Si:O alloy have been systematically characterized in the optical absorption and electrical transport behavior, by varying the Si content from 43 up to 100 at. %. Magnetron sputtering or plasma enhanced chemical vapor deposition have been used for the Si:O alloy deposition, followed by annealing up to 1250 deg. C. Boron implantation (30 keV, 3-30x10{sup 14} B/cm{sup 2}) on selected samples was performed to vary the electrical sheet resistance measured by the four-point collinear probe method. Transmittance and reflectance spectra have been extracted and combined to estimate the absorption spectra and the optical band gap, by means of the Tauc analysis. Raman spectroscopy was also employed to follow the amorphous-crystalline (a-c) transition of the Si domains contained in the Si:O films. The optical absorption and the electrical transport of Si:O films can be continuously and independently modulated by acting on different parameters. The light absorption increases (by one decade) with the Si content in the 43-100 at. % range, determining an optical band gap which can be continuously modulated into the 2.6-1.6 eV range, respectively. The a-c phase transition in Si:O films, causing a significant reduction in the absorption coefficient, occurs at increasing temperatures (from 600 to 1100 deg. C) as the Si content decreases. The electrical resistivity of Si:O films can be varied among five decades, being essentially dominated by the number of Si grains and by the doping. Si:O alloys with Si content in the 60-90 at. % range (named oxygen rich silicon films), are proved to join an appealing optical gap with a viable conductivity, being a good candidate for increasing the conversion efficiency of thin-film photovoltaic cell.

  8. Using Radar, Lidar and Radiometer Data from NSA and SHEBA to Quantify Cloud Property Effects on the Surface Heat Budget in the Arctic

    SciTech Connect (OSTI)

    Janet Intrieri; Mathhew Shupe

    2005-01-01

    Cloud and radiation data from two distinctly different Arctic areas are analyzed to study the differences between coastal Alaskan and open Arctic Ocean region clouds and their respective influence on the surface radiation budget. The cloud and radiation datasets were obtained from (1) the DOE North Slope of Alaska (NSA) facility in the coastal town of Barrow, Alaska, and (2) the SHEBA field program, which was conducted from an icebreaker frozen in, and drifting with, the sea-ice for one year in the Western Arctic Ocean. Radar, lidar, radiometer, and sounding measurements from both locations were used to produce annual cycles of cloud occurrence and height, atmospheric temperature and humidity, surface longwave and shortwave broadband fluxes, surface albedo, and cloud radiative forcing. In general, both regions revealed a similar annual trend of cloud occurrence fraction with minimum values in winter (60-75%) and maximum values during spring, summer and fall (80-90%). However, the annual average cloud occurrence fraction for SHEBA (76%) was lower than the 6-year average cloud occurrence at NSA (92%). Both Arctic areas also showed similar annual cycle trends of cloud forcing with clouds warming the surface through most of the year and a period of surface cooling during the summer, when cloud shading effects overwhelm cloud greenhouse effects. The greatest difference between the two regions was observed in the magnitude of the cloud cooling effect (i.e., shortwave cloud forcing), which was significantly stronger at NSA and lasted for a longer period of time than at SHEBA. This is predominantly due to the longer and stronger melt season at NSA (i.e., albedo values that are much lower coupled with Sun angles that are somewhat higher) than the melt season observed over the ice pack at SHEBA. Longwave cloud forcing values were comparable between the two sites indicating a general similarity in cloudiness and atmospheric temperature and humidity structure between the two regions.

  9. Carbon dioxide postcombustion capture: a novel screening study of the carbon dioxide absorption performance of 76 amines

    SciTech Connect (OSTI)

    Graeme Puxty; Robert Rowland; Andrew Allport; Qi Yang; Mark Bown; Robert Burns; Marcel Maeder; Moetaz Attalla

    2009-08-15

    The significant and rapid reduction of greenhouse gas emissions is recognized as necessary to mitigate the potential climate effects from global warming. The postcombustion capture (PCC) and storage of carbon dioxide (CO{sub 2}) produced from the use of fossil fuels for electricity generation is a key technology needed to achieve these reductions. The most mature technology for CO{sub 2} capture is reversible chemical absorption into an aqueous amine solution. In this study the results from measurements of the CO{sub 2} absorption capacity of aqueous amine solutions for 76 different amines are presented. Measurements were made using both a novel isothermal gravimetric analysis (IGA) method and a traditional absorption apparatus. Seven amines, consisting of one primary, three secondary, and three tertiary amines, were identified as exhibiting outstanding absorption capacities. Most have a number of structural features in common including steric hindrance and hydroxyl functionality 2 or 3 carbons from the nitrogen. Initial CO{sub 2} absorption rate data from the IGA measurements was also used to indicate relative absorption rates. Most of the outstanding performers in terms of capacity also showed initial absorption rates comparable to the industry standard monoethanolamine (MEA). This indicates, in terms of both absorption capacity and kinetics, that they are promising candidates for further investigation. 30 refs., 8 figs.

  10. The role of the carbon-silicon complex in eliminating deep ultraviolet absorption in AlN

    SciTech Connect (OSTI)

    Gaddy, BE; Bryan, Z; Bryan, I; Xie, JQ; Dalmau, R; Moody, B; Kumagai, Y; Nagashima, T; Kubota, Y; Kinoshita, T; Koukitu, A; Kirste, R; Sitar, Z; Collazo, R; Irving, DL

    2014-05-19

    Co-doping AlN crystals with Si is found to suppress the unwanted 4.7 eV (265 nm) deep ultraviolet absorption associated with isolated carbon acceptors common in materials grown by physical vapor transport. Density functional theory calculations with hybrid functionals demonstrate that silicon forms a stable nearest-neighbor defect complex with carbon. This complex is predicted to absorb at 5.5 eV and emit at or above 4.3 eV. Absorption and photoluminescence measurements of co-doped samples confirm the presence of the predicted C-N-Si-Al complex absorption and emission peaks and significant reduction of the 4.7 eV absorption. Other sources of deep ultraviolet absorption in AlN are also discussed. (C) 2014 AIP Publishing LLC.

  11. Specific absorption rate calculations of magnetite, using a modified linear response model for applications in magnetic hyperthermia

    SciTech Connect (OSTI)

    Hernndez S, A. E-mail: meduardo2001@hotmail.com; Cano, M. E. E-mail: meduardo2001@hotmail.com; Torres-Arenas, J.

    2014-11-07

    Currently the absorption of electromagnetic radiation by magnetic nanoparticles is studied for biomedical applications of cancer thermotherapy. Several experiments are conduced following the framework of the Rosensweig model, in order to estimate their specific absorption rate. Nevertheless, this linear approximation involves strong simplifications which constrain their accuracy and validity range. The main aim of this work is to incorporate the deviation of the sphericity assumption in particles shapes, to improve the determination of their specific absorption rate. The correction to the effective particles volume is computed as a measure of the apparent amount of magnetic material, interacting with the external AC magnetic field. Preliminary results using the physical properties of Fe3O4 nanoparticles, exhibit an important correction in their estimated specific absorption rate, as a function of the apparent mean particles radius. Indeed, we have observed using a small deviation (6% of the apparent radius), up to 40% of the predicted specific absorption rate by the Rosensweig linear approximation.

  12. Regeneration of an aqueous solution from an acid gas absorption process by matrix stripping

    DOE Patents [OSTI]

    Rochelle, Gary T. (Austin, TX); Oyenekan, Babatunde A. (Katy, TX)

    2011-03-08

    Carbon dioxide and other acid gases are removed from gaseous streams using aqueous absorption and stripping processes. By replacing the conventional stripper used to regenerate the aqueous solvent and capture the acid gas with a matrix stripping configuration, less energy is consumed. The matrix stripping configuration uses two or more reboiled strippers at different pressures. The rich feed from the absorption equipment is split among the strippers, and partially regenerated solvent from the highest pressure stripper flows to the middle of sequentially lower pressure strippers in a "matrix" pattern. By selecting certain parameters of the matrix stripping configuration such that the total energy required by the strippers to achieve a desired percentage of acid gas removal from the gaseous stream is minimized, further energy savings can be realized.

  13. Cascading metallic gratings for broadband absorption enhancement in ultrathin plasmonic solar cells

    SciTech Connect (OSTI)

    Wen, Long; Sun, Fuhe; Chen, Qin

    2014-04-14

    The incorporation of plasmonic nanostructures in the thin-film solar cells (TFSCs) is a promising route to harvest light into the nanoscale active layer. However, the light trapping scheme based on the plasmonic effects intrinsically presents narrow-band resonant enhancement of light absorption. Here we demonstrate that by cascading metal nanogratings with different sizes atop the TFSCs, broadband absorption enhancement can be realized by simultaneously exciting multiple localized surface plasmon resonances and inducing strong coupling between the plasmonic modes and photonic modes. As a proof of concept, we demonstrate of 66.5% in the photocurrent in an ultrathin amorphous silicon TFSC with two-dimensional cascaded gratings over the reference cell without gratings.

  14. Theory of triplet optical absorption in oligoacenes: From naphthalene to heptacene

    SciTech Connect (OSTI)

    Chakraborty, Himanshu Shukla, Alok

    2014-10-28

    In this paper, we present a detailed theory of the triplet states of oligoacenes containing up to seven rings, i.e., starting from naphthalene all the way up to heptacene. In particular, we present results on the optical absorption from the first triplet excited state 1{sup 3}B{sub 2u}{sup +} of these oligomers, computed using the Pariser-Parr-Pople model Hamiltonian, and a correlated electron approach employing the configuration-interaction methodology at various levels. Excitation energies of various triplets states obtained by our calculations are in good agreement with the experimental results, where available. The computed triplet spectra of oligoacenes exhibits rich structure dominated by two absorption peaks of high intensities, which are well separated in energy, and are caused by photons polarized along the conjugation direction. This prediction of ours can be tested in future experiments performed on oriented samples of oligoacenes.

  15. Reflection-Absorption Infrared Spectroscopy of Thin Films Using an External Cavity Quantum Cascade Laser

    SciTech Connect (OSTI)

    Phillips, Mark C.; Craig, Ian M.; Blake, Thomas A.

    2013-02-04

    We present experimental demonstrations using a broadly tunable external cavity quantum cascade laser (ECQCL) to perform Reflection-Absorption InfraRed Spectroscopy (RAIRS) of thin layers and residues on surfaces. The ECQCL compliance voltage was used to measure fluctuations in the ECQCL output power and improve the performance of the RAIRS measurements. Absorption spectra from self-assembled monolayers of a fluorinated alkane thiol and a thiol carboxylic acid were measured and compared with FTIR measurements. RAIRS spectra of the explosive compounds PETN, RDX, and tetryl deposited on gold substrates were also measured. Rapid measurement times and low noise were demonstrated, with < 1E-3 absorbance noise for a 10 second measurement time.

  16. New constraints in absorptive capacity and the optimum rate of petroleum output

    SciTech Connect (OSTI)

    El Mallakh, R

    1980-01-01

    Economic policy in four oil-producing countries is analyzed within a framework that combines a qualitative assessment of the policy-making process with an empirical formulation based on historical and current trends in these countries. The concept of absorptive capacity is used to analyze the optimum rates of petroleum production in Iran, Iraq, Saudi Arabia, and Kuwait. A control solution with an econometric model is developed which is then modified for alternative development strategies based on analysis of factors influencing production decisions. The study shows the consistencies and inconsistencies between the goals of economic growth, oil production, and exports, and the constraints on economic development. Simulation experiments incorporated a number of the constraints on absorptive capacity. Impact of other constraints such as income distribution and political stability is considered qualitatively. (DLC)

  17. Differential total absorptivity solution to the radiative transfer equation for mixtures of combustion gases and soot

    SciTech Connect (OSTI)

    Bressloff, N.W.; Moss, J.B.; Rubini, P.A.

    1997-01-01

    The differential total absorptivity (DTA) solution to the radiative transfer equation, originally devised for combustion gases in the discrete transfer radiation model, is extended to mixtures of gaseous combustion products and soot. The method is compared to other solution techniques for representative mixtures across single lines of sight and across a layer bounded by solid walls. Intermediate soot loadings are considered such that the total radiance is not dominated by either the gaseous or soot components. The DTA solution is shown to yield excellent accuracy relative to a narrow-band solution, with a considerable saving in computational cost. Thus, explicit treatment of the source temperature dependence of absorption is successfully demonstrated without the need for spectral integration.

  18. Process for removal of carbonyl sulfide in liquified hydrocarbon gases with absorption of acid gases

    SciTech Connect (OSTI)

    Beavon, D.K.; Mackles, M.

    1980-11-11

    Liquified hydrocarbon gases containing at least carbonyl sulfide as an impurity are purified by intimately mixing the liquified hydrocarbon gas with an aqueous absorbent for hydrogen sulfide in a hydrolysis zone maintained at a temperature and a pressure sufficient to maintain the liquified hydrocarbon gas in the liquid state and hydrolyze the carbonyl sulfide to hydrogen sulfide and carbon dioxide. The liquified hydrocarbon gas containing at least a portion of the formed carbonyl sulfide and carbon dioxide is separated from the liquid absorbent and passed to an absorption zone where it is contacted with a liquid hydrogen sulfide absorbent where at least the formed hydrogen sulfide is separated from the liquified petroleum gas. A stage of absorption of at least hydrogen sulfide may proceed mixing of the liquified hydrocarbon gas with the absorbent in the hydrolysis reaction zone. The absorbent employed does not combine irreversibly with carbonyl sulfide, hydrogen sulfide, and carbon dioxide, and preferably is an aqueous solution of diethanolamine.

  19. An improved absorption generator for solar-thermal powered heat pumps. Part 1: Feasibility

    SciTech Connect (OSTI)

    Fineblum, S.

    1997-12-31

    Solar heated absorption chiller installations have been, typically, very expensive for their rating. The need to keep the liquid flowing within the collectors as cool as possible to enhance collector thermal efficiency, conflicts with the need to operate the absorption chiller at a higher temperature. The compromise usually results in poor collector efficiency as well as a relatively poor specific chiller effect. The proposed vortex generator permits a heat pump to operate efficiently with relatively low temperature solar heated fluid (70--80 C). As a result, the collectors are cooler and much more efficient. In addition, the specific heat pumping capacity is about 27% greater than conventional systems operating at the same reduced generator temperatures and, therefore, a smaller chiller is required. The economic consequences of these benefits will be presented in Part 2.

  20. Atomic structure of machined semiconducting chips: An x-ray absorption spectroscopy study

    SciTech Connect (OSTI)

    Paesler, M.; Sayers, D.

    1988-12-01

    X-ray absorption spectroscopy (XAS) has been used to examine the atomic structure of chips of germanium that were produced by single point diamond machining. It is demonstrated that although the local (nearest neighbor) atomic structure is experimentally quite similar to that of single crystal specimens information from more distant atoms indicates the presence of considerable stress. An outline of the technique is given and the strength of XAS in studying the machining process is demonstrated.

  1. Geek-Up[6.10.10]: Attosecond Absorption Spectroscopy and Kinked Nanopores |

    Broader source: Energy.gov (indexed) [DOE]

    Department of Energy A classical diagram of a krypton atom shows its 36 electrons arranged in shells. | Photo Courtesy of: Berkeley Lab. A classical diagram of a krypton atom shows its 36 electrons arranged in shells. | Photo Courtesy of: Berkeley Lab. Elizabeth Meckes Elizabeth Meckes Director of User Experience & Digital Technologies, Office of Public Affairs Thanks to the attosecond absorption spectroscopy process, an international team of scientists from Max Planck Institute of

  2. Synchrotron X-ray fluorescence and absorption of rare earth elements in

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    fossils: implications for anatomical and taphonomical studies | Stanford Synchrotron Radiation Lightsource Synchrotron X-ray fluorescence and absorption of rare earth elements in fossils: implications for anatomical and taphonomical studies Wednesday, January 27, 2016 - 3:00pm SLAC, Redtail Hawk Conference Room 108A Speaker: Pierre Gueriau, Synchrotron SOLEIL Program Description Synchrotron-based X-ray fluorescence (SR-XRF) has mainly been used in fossils to map organics and metal

  3. Laser plasma x-ray source for ultrafast time-resolved x-ray absorption spectroscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Miaja-Avila, L.; O'Neil, G. C.; Uhlig, J.; Cromer, C. L.; Dowell, M. L.; Jimenez, R.; Hoover, A. S.; Silverman, K. L.; Ullom, J. N.

    2015-03-02

    We describe a laser-driven x-ray plasma source designed for ultrafast x-ray absorption spectroscopy. The source is comprised of a 1 kHz, 20 W, femtosecond pulsed infrared laser and a water target. We present the x-ray spectra as a function of laser energy and pulse duration. Additionally, we investigate the plasma temperature and photon flux as we vary the laser energy. We obtain a 75 μm FWHM x-ray spot size, containing ~106 photons/s, by focusing the produced x-rays with a polycapillary optic. Since the acquisition of x-ray absorption spectra requires the averaging of measurements from >107 laser pulses, we also presentmore » data on the source stability, including single pulse measurements of the x-ray yield and the x-ray spectral shape. In single pulse measurements, the x-ray flux has a measured standard deviation of 8%, where the laser pointing is the main cause of variability. Further, we show that the variability in x-ray spectral shape from single pulses is low, thus justifying the combining of x-rays obtained from different laser pulses into a single spectrum. Finally, we show a static x-ray absorption spectrum of a ferrioxalate solution as detected by a microcalorimeter array. Altogether, our results demonstrate that this water-jet based plasma source is a suitable candidate for laboratory-based time-resolved x-ray absorption spectroscopy experiments.« less

  4. The impact of biogenic carbon emissions on aerosol absorption inMexico City

    SciTech Connect (OSTI)

    Marley, N; Gaffney, J; Tackett, M J; Sturchio, N; Hearty, L; Martinez, N; Hardy, K D; Machany-Rivera, A; Guilderson, T P; MacMillan, A; Steelman, K

    2009-02-24

    In order to determine the wavelength dependence of atmospheric aerosol absorption in the Mexico City area, the absorption angstrom exponents (AAEs) were calculated from aerosol absorption measurements at seven wavelengths obtained with a seven-channel aethalometer during two field campaigns, the Mexico City Metropolitan Area study in April 2003 (MCMA 2003) and the Megacity Initiative: Local and Global Research Observations in March 2006 (MILAGRO). The AAEs varied from 0.76 to 1.56 in 2003 and from 0.54 to 1.52 in 2006. The AAE values determined in the afternoon were consistently higher than the corresponding morning values, suggesting the photochemical formation of absorbing secondary organic aerosols (SOA) in the afternoon. The AAE values were compared to stable and radiocarbon isotopic measurements of aerosol samples collected at the same time to determine the sources of the aerosol carbon. The fraction of modern carbon (fM) in the aerosol samples, as determined from {sup 14}C analysis, showed that 70% of the carbonaceous aerosols in Mexico City were from modern sources, indicating a significant impact from biomass burning during both field campaigns. The {sup 13}C/{sup 12}C ratios of the aerosol samples illustrate the significant impact of Yucatan forest fires (C-3 plants) in 2003 and local grass fires (C-4 plants) at site T1 in 2006. A direct comparison of the fM values, stable carbon isotope ratios, and calculated aerosol AAEs suggested that the wavelength dependence of the aerosol absorption was controlled by the biogenically derived aerosol components.

  5. Nonequilibrium Green's function formulation of intersubband absorption for nonparabolic single-band effective mass Hamiltonian

    SciTech Connect (OSTI)

    Kolek, Andrzej

    2015-05-04

    The formulas are derived that enable calculations of intersubband absorption coefficient within nonequilibrium Green's function method applied to a single-band effective-mass Hamiltonian with the energy dependent effective mass. The derivation provides also the formulas for the virtual valence band components of the two-band Green's functions which can be used for more exact estimation of the density of states and electrons and more reliable treatment of electronic transport in unipolar n-type heterostructure semiconductor devices.

  6. DOE/SC-ARM-14-013 Continuous Light Absorption Photometer (CLAP) Final Campaign Report

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    3 Continuous Light Absorption Photometer (CLAP) Final Campaign Report A Jefferson May 2014 DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not

  7. Absorption and scattering of laser radiation by the diffusion flame of aviation kerosene

    SciTech Connect (OSTI)

    Gvozdev, S V; Glova, A F; Dubrovskii, V Yu; Durmanov, S T; Krasyukov, A G; Lysikov, A Yu; Smirnov, G V; Solomakhin, V B

    2012-04-30

    The absorption coefficient of the radiation of a repetitively pulsed Nd : YAG laser with an average output power up to 6 W and of a cw ytterbium optical fibre laser with an output power up to 3 kW was measured in the diffusion flame of aviation kerosene burning on a free surface in the atmospheric air. The absorption coefficient as a function of flame length, radiation power, and radiation intensity, which was varied in the {approx}10{sup 3} - 5 Multiplication-Sign 10{sup 4} W cm{sup -2} range, was obtained for two distances (1 and 2 cm) between the laser beam axis and the surface. The coefficient of radiation absorption by kerosene flame was compared with that in ethanol and kerosene - ethanol mixture flames. The radiation power scattered by a small segment of the kerosene flame irradiated by Nd : YAG laser radiation was measured as a function of longitudinal and azimuthal coordinates. An estimate was made of the total scattered radiation power.

  8. THE EFFECT OF 3HE ON LOW PRESSURE HYDRIDE ABSORPTION MEASUREMENTS WITH TRITIUM

    SciTech Connect (OSTI)

    Staack, G.; Klein, J.

    2011-01-20

    Absorption isotherm data exists for a wide variety of hydrogen-metal systems. When working with high purity gases, appropriately sized equipment, and hydrides with equilibrium pressures above several hundred Pa, data collection is relatively straightforward. Special consideration must be given to experiments involving low equilibrium pressure hydrides, as even sub-ppm levels of gas impurities can generate partial pressures many times greater than the equilibrium pressures to be measured. Tritium absorption experiments are further complicated by the continuous generation of helium-3. The time required to transfer and absorb a known quantity of tritium onto a sample ultimately limits the minimum pressure range that can be studied using the standard technique. Equations are presented which show the pressure of helium-3 in a sample cell based on the amount of tritium to be absorbed, the sample cell volume and temperature, and the decay time of tritium. Sample calculations for zirconium show that at 300 C, the estimated helium-3 pressure in the cell will be equal to the hydrogen absorption pressure after only milliseconds of tritium decay. An alternate method is presented that permits the collection of equilibrium data at pressures orders of magnitude lower than possible using a direct approach.

  9. Method and apparatus for measuring butterfat and protein content using microwave absorption techniques

    DOE Patents [OSTI]

    Fryer, Michael O.; Hills, Andrea J.; Morrison, John L.

    2000-01-01

    A self calibrating method and apparatus for measuring butterfat and protein content based on measuring the microwave absorption of a sample of milk at several microwave frequencies. A microwave energy source injects microwave energy into the resonant cavity for absorption and reflection by the sample undergoing evaluation. A sample tube is centrally located in the resonant cavity passing therethrough and exposing the sample to the microwave energy. A portion of the energy is absorbed by the sample while another portion of the microwave energy is reflected back to an evaluation device such as a network analyzer. The frequency at which the reflected radiation is at a minimum within the cavity is combined with the scatter coefficient S.sub.11 as well as a phase change to calculate the butterfat content in the sample. The protein located within the sample may also be calculated in a likewise manner using the frequency, S.sub.11 and phase variables. A differential technique using a second resonant cavity containing a reference standard as a sample will normalize the measurements from the unknown sample and thus be self-calibrating. A shuttered mechanism will switch the microwave excitation between the unknown and the reference cavities. An integrated apparatus for measuring the butterfat content in milk using microwave absorption techniques is also presented.

  10. Femtosecond x-ray absorption spectroscopy with hard x-ray free electron laser

    SciTech Connect (OSTI)

    Katayama, Tetsuo; Togashi, Tadashi; Tono, Kensuke; Kameshima, Takashi; Inubushi, Yuichi; Sato, Takahiro; Hatsui, Takaki; Yabashi, Makina; Obara, Yuki; Misawa, Kazuhiko; Bhattacharya, Atanu; Kurahashi, Naoya; Ogi, Yoshihiro; Suzuki, Toshinori; Molecular Reaction Dynamics Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako 351-0198

    2013-09-23

    We have developed a method of dispersive x-ray absorption spectroscopy with a hard x-ray free electron laser (XFEL), generated by a self-amplified spontaneous emission (SASE) mechanism. A transmission grating was utilized for splitting SASE-XFEL light, which has a relatively large bandwidth (ΔE/E ∼ 5 × 10{sup −3}), into several branches. Two primary split beams were introduced into a dispersive spectrometer for measuring signal and reference spectra simultaneously. After normalization, we obtained a Zn K-edge absorption spectrum with a photon-energy range of 210 eV, which is in excellent agreement with that measured by a conventional wavelength-scanning method. From the analysis of the difference spectra, the noise ratio was evaluated to be ∼3 × 10{sup −3}, which is sufficiently small to trace minute changes in transient spectra induced by an ultrafast optical laser. This scheme enables us to perform single-shot, high-accuracy x-ray absorption spectroscopy with femtosecond time resolution.

  11. Structural color printing based on plasmonic metasurfaces of perfect light absorption

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Cheng, Fei; Gao, Jie; Luk, Ting S.; Yang, Xiaodong

    2015-06-05

    Subwavelength structural color filtering and printing technologies employing plasmonic nanostructures have recently been recognized as an important and beneficial complement to the traditional colorant-based pigmentation. However, the color saturation, brightness and incident angle tolerance of structural color printing need to be improved to meet the application requirement. Here we demonstrate a structural color printing method based on plasmonic metasurfaces of perfect light absorption to improve color performances such as saturation and brightness. Thin-layer perfect absorbers with periodic hole arrays are designed at visible frequencies and the absorption peaks are tuned by simply adjusting the hole size and periodicity. Near perfectmore » light absorption with high quality factors are obtained to realize high-resolution, angle-insensitive plasmonic color printing with high color saturation and brightness. Moreover, the fabricated metasurfaces can be protected with a protective coating for ambient use without degrading performances. The demonstrated structural color printing platform offers great potential for applications ranging from security marking to information storage.« less

  12. Solidification of Acidic, High Nitrate Nuclear Wastes by Grouting or Absorption on Silica Gel

    SciTech Connect (OSTI)

    A. K. Herbst; S. V. Raman; R. J. Kirkham

    2004-01-01

    The use of grout and silica gel were explored for the solidification of four types of acidic, high nitrate radioactive wastes. Two methods of grouting were tested: direct grouting and pre-neutralization. Two methods of absorption on silica gel were also tested: direct absorption and rotary spray drying. The waste simulant acidity varied between 1 N and 12 N. The waste simulant was neutralized by pre-blending calcium hydroxide with Portland cement and blast furnace slag powders prior to mixing with the simulant for grout solidification. Liquid sodium hydroxide was used to partially neutralize the simulant to a pH above 2 and then it was absorbed for silica gel solidification. Formulations for each of these methods are presented along with waste form characteristics and properties. Compositional variation maps for grout formulations are presented which help determine the optimum "recipe" for a particular waste stream. These maps provide a method to determine the proportions of waste, calcium hydroxide, Portland cement, and blast furnace slag that provide a waste form that meets the disposal acceptance criteria. The maps guide researchers in selecting areas to study and provide an operational envelop that produces acceptable waste forms. The grouts both solidify and stabilize the wastes, while absorption on silica gel produces a solid waste that will not pass standard leaching procedures (TCLP) if required. Silica gel wastes can be made to pass most leach tests if heated to 600C.

  13. Optimization of a solar powered absorption cycle under Abu Dhabi's weather conditions

    SciTech Connect (OSTI)

    Al-Alili, A.; Hwang, Y.; Radermacher, R.; Kubo, I.

    2010-12-15

    In order for the solar absorption air conditioners to become a real alternative to the conventional vapour compression systems, their performance has to be improved and their total cost has to be reduced. A solar powered absorption cycle is modeled using the Transient System Simulation (TRNSYS) program and Typical Meteorological Year 2 data of Abu Dhabi. It uses evacuated tube collectors to drive a 10 kW ammonia-water absorption chiller. Firstly, the system performance and its total cost are optimized separately using single objective optimization algorithms. The design variables considered are: the collector slope, the collector mass flow rate, the collector area and the storage tank volume. The single objective optimization results show that MATLAB global optimization methods agree with the TRNSYS optimizer. Secondly, MATLAB is used to solve a multi-objective optimization problem to improve the system's performance and cost, simultaneously. The optimum designs are presented using Pareto curve and show the potential improvements of the baseline system. (author)

  14. Particle size effect of hydride formation and surface hydrogen absorption of nanosized palladium catalysts : L{sub 3} edge vs K edge x-ray absorption spectroscopy.

    SciTech Connect (OSTI)

    Tew, M. W.; Miller, J. T.; van Bokhoven, J. A.

    2009-08-01

    The particle size effect on the formation of palladium hydride and on surface hydrogen adsorption was studied at room temperature using in situ X-ray absorption spectroscopy at the Pd K and L{sub 3} edges. Hydride formation was indirectly observed by lattice expansion in Pd K edge XANES spectra and by EXAFS analysis. Hydride formation was directly detected in the L{sub 3} edge spectra. A characteristic spectral feature caused by the formation of a Pd-H antibonding state showed strong particle size dependence. The L{sub 3} edge spectra were reproduced using full multiple scattering analysis and density of state calculations, and the contributions of bulk absorbed and surface hydrogen to the XANES spectra could be distinguished. The ratio of hydrogen on the surface versus that in the bulk increased with decreasing particle size, and smaller particles dissolved less hydrogen.

  15. Enhanced Solar Energy Absorption by Internally-mixed Black Carbon in Snow Grains

    SciTech Connect (OSTI)

    Flanner, M. G.; Liu, Xiaohong; Zhou, Cheng; Penner, Joyce E.; Jiao, C.

    2012-05-30

    Here we explore light absorption by snowpack containing black carbon (BC) particles residing within ice grains. Basic considerations of particle volumes and BC/snow mass concentrations show that there are generally 0:05-109 BC particles for each ice grain. This suggests that internal BC is likely distributed as multiple inclusions within ice grains, and thus the dynamic effective medium approximation (DEMA) (Chylek and Srivastava, 1983) is a more appropriate optical representation for BC/ice composites than coated-sphere or standard mixing approximations. DEMA calculations show that the 460 nm absorption cross-section of BC/ice composites, normalized to the mass of BC, is typically enhanced by factors of 1.8-2.1 relative to interstitial BC. BC effective radius is the dominant cause of variation in this enhancement, compared with ice grain size and BC volume fraction. We apply two atmospheric aerosol models that simulate interstitial and within-hydrometeor BC lifecycles. Although only {approx}2% of the atmospheric BC burden is cloud-borne, 71-83% of the BC deposited to global snow and sea-ice surfaces occurs within hydrometeors. Key processes responsible for within-snow BC deposition are development of hydrophilic coatings on BC, activation of liquid droplets, and subsequent snow formation through riming or ice nucleation by other species and aggregation/accretion of ice particles. Applying deposition fields from these aerosol models in offline snow and sea-ice simulations, we calculate that 32-73% of BC in global surface snow resides within ice grains. This fraction is smaller than the within-hydrometeor deposition fraction because meltwater flux preferentially removes internal BC, while sublimation and freezing within snowpack expose internal BC. Incorporating the DEMA into a global climate model, we simulate increases in BC/snow radiative forcing of 43-86%, relative to scenarios that apply external optical properties to all BC. We show that snow metamorphism driven by diffusive vapor transfer likely proceeds too slowly to alter the mass of internal BC while it is radiatively active, but neglected processes like wind pumping and convection may play much larger roles. These results suggest that a large portion of BC in surface snowpack may reside within ice grains and increase BC/snow radiative forcing, although measurements to evaluate this are lacking. Finally, previous studies of BC/snow forcing that neglected this absorption enhancement are not necessarily biased low, because of application of absorption-enhancing sulfate coatings to hydrophilic BC, neglect of coincident absorption by dust in snow, and implicit treatment of cloud-borne BC resulting in longer-range transport.

  16. CO AND H{sub 2} ABSORPTION IN THE AA TAURI CIRCUMSTELLAR DISK

    SciTech Connect (OSTI)

    France, Kevin; Burgh, Eric B.; Schindhelm, Eric; Brown, Alexander; Herczeg, Gregory J.; Yang, Hao; Linsky, Jeffrey L.; Abgrall, Herve; Roueff, Evelyne; Brown, Joanna M.

    2012-01-01

    The direct study of molecular gas in inner protoplanetary disks is complicated by uncertainties in the spatial distribution of the gas, the time variability of the source, and the comparison of observations across a wide range of wavelengths. Some of these challenges can be mitigated with far-ultraviolet spectroscopy. Using new observations obtained with the Hubble Space Telescope Cosmic Origins Spectrograph, we measure column densities and rovibrational temperatures for CO and H{sub 2} observed on the line of sight through the AA Tauri circumstellar disk. CO A - X absorption bands are observed against the far-UV continuum. The CO absorption is characterized by log{sub 10}(N({sup 12}CO)) = 17.5 {+-} 0.5 cm{sup -2} and T{sub rot}(CO) = 500{sup +500}{sub -200} K, although this rotational temperature may underestimate the local kinetic temperature of the CO-bearing gas. We also detect {sup 13}CO in absorption with an isotopic ratio of {approx}20. We do not observe H{sub 2} absorption against the continuum; however, hot H{sub 2} (v > 0) is detected in absorption against the Ly{alpha} emission line. We measure the column densities in eight individual rovibrational states, determining a total log{sub 10}(N(H{sub 2})) = 17.9{sup +0.6}{sub -0.3} cm{sup -2} with a thermal temperature of T(H{sub 2}) = 2500{sup +800}{sub -700} K. The high temperature of the molecules, the relatively small H{sub 2} column density, and the high inclination of the AA Tauri disk suggest that the absorbing gas resides in an inner disk atmosphere. If the H{sub 2} and CO are cospatial within a molecular layer {approx}0.6 AU thick, this region is characterized by {approx} 10{sup 5} cm{sup -3} with an observed (CO/H{sub 2}) ratio of {approx}0.4. We also find evidence for a departure from a purely thermal H{sub 2} distribution, suggesting that excitation by continuum photons and H{sub 2} formation may be altering the level populations in the molecular gas.

  17. A Novel Absorption Cycle for Combined Water Heating, Dehumidification, and Evaporative Cooling

    SciTech Connect (OSTI)

    CHUGH, Devesh; Gluesenkamp, Kyle R; Abdelaziz, Omar; Moghaddam, Saeed

    2014-01-01

    In this study, development of a novel system for combined water heating, dehumidification, and space evaporative cooling is discussed. Ambient water vapor is used as a working fluid in an open system. First, water vapor is absorbed from an air stream into an absorbent solution. The latent heat of absorption is transferred into the process water that cools the absorber. The solution is then regenerated in the desorber, where it is heated by a heating fluid. The water vapor generated in the desorber is condensed and its heat of phase change is transferred to the process water in the condenser. The condensed water can then be used in an evaporative cooling process to cool the dehumidified air exiting the absorber, or it can be drained if primarily dehumidification is desired. Essentially, this open absorption cycle collects space heat and transfers it to process water. This technology is enabled by a membrane-based absorption/desorption process in which the absorbent is constrained by hydrophobic vapor-permeable membranes. Constraining the absorbent film has enabled fabrication of the absorber and desorber in a plate-and-frame configuration. An air stream can flow against the membrane at high speed without entraining the absorbent, which is a challenge in conventional dehumidifiers. Furthermore, the absorption and desorption rates of an absorbent constrained by a membrane are greatly enhanced. Isfahani and Moghaddam (Int. J. Heat Mass Transfer, 2013) demonstrated absorption rates of up to 0.008 kg/m2s in a membrane-based absorber and Isfahani et al. (Int. J. Multiphase Flow, 2013) have reported a desorption rate of 0.01 kg/m2s in a membrane-based desorber. The membrane-based architecture also enables economical small-scale systems, novel cycle configurations, and high efficiencies. The absorber, solution heat exchanger, and desorber are fabricated on a single metal sheet. In addition to the open arrangement and membrane-based architecture, another novel feature of the cycle is recovery of the solution heat energy exiting the desorber by process water (a process-solution heat exchanger ) rather than the absorber exiting solution (the conventional solution heat exchanger ). This approach has enabled heating the process water from an inlet temperature of 15 C to 57 C (conforming to the DOE water heater test standard) and interfacing the process water with absorbent on the opposite side of a single metal sheet encompassing the absorber, process-solution heat exchanger, and desorber. The system under development has a 3.2 kW water heating capacity and a target thermal coefficient of performance (COP) of 1.6.

  18. Temperature dependence of the Pd [ital K]-edge extended x-ray-absorption fine structure of PdC[sub [ital x

    SciTech Connect (OSTI)

    McCaulley, J.A. (Hoechst Celanese Research Division, Robert L. Mitchell Technical Center, 86 Morris Avenue, Summit, New Jersey 07901 (United States))

    1993-03-01

    Pd [ital K]-edge extended x-ray-absorption fine-structure (EXAFS) and x-ray-absorption near-edge-structure (XANES) measurements were performed on a Pd carbide phase, PdC[sub [ital x

  19. Simulation of energy absorption spectrum in NaI crystal detector for multiple gamma energy using Monte Carlo method

    SciTech Connect (OSTI)

    Wirawan, Rahadi; Waris, Abdul; Djamal, Mitra; Handayani, Gunawan

    2015-04-16

    The spectrum of gamma energy absorption in the NaI crystal (scintillation detector) is the interaction result of gamma photon with NaI crystal, and it’s associated with the photon gamma energy incoming to the detector. Through a simulation approach, we can perform an early observation of gamma energy absorption spectrum in a scintillator crystal detector (NaI) before the experiment conducted. In this paper, we present a simulation model result of gamma energy absorption spectrum for energy 100-700 keV (i.e. 297 keV, 400 keV and 662 keV). This simulation developed based on the concept of photon beam point source distribution and photon cross section interaction with the Monte Carlo method. Our computational code has been successfully predicting the multiple energy peaks absorption spectrum, which derived from multiple photon energy sources.

  20. Quantitative broadband absorption and scattering spectroscopy in turbid media by combined frequency-domain and steady state methodologies

    DOE Patents [OSTI]

    Tromberg, Bruce J.; Berger, Andrew J.; Cerussi, Albert E.; Bevilacqua, Frederic; Jakubowski, Dorota

    2008-09-23

    A technique for measuring broadband near-infrared absorption spectra of turbid media that uses a combination of frequency-domain and steady-state reflectance methods. Most of the wavelength coverage is provided by a white-light steady-state measurement, whereas the frequency-domain data are acquired at a few selected wavelengths. Coefficients of absorption and reduced scattering derived from the frequency-domain data are used to calibrate the intensity of the steady-state measurements and to determine the reduced scattering coefficient at all wavelengths in the spectral window of interest. The absorption coefficient spectrum is determined by comparing the steady-state reflectance values with the predictions of diffusion theory, wavelength by wavelength. Absorption spectra of a turbid phantom and of human breast tissue in vivo, derived with the combined frequency-domain and steady-state technique, agree well with expected reference values.

  1. Alternation of the Pd Lattice in Nano-Sized-Pd/ZrO2 Composite during Hydrogen Absorption

    SciTech Connect (OSTI)

    Arachi, Yoshinori; Asai, Takeshi; Emura, Shuichi; Omura, Akira; Nunogaki, Masanobu; Yamaura, Shunichi; Inoue, Akihisa; Arata, Yoshiaki

    2007-02-02

    Structural analysis of high Deuterium absorbed 5 nm Pd particles in dispersed ZrO2 has been carried out using XAFS techniques. X-ray absorption spectra around the Pd K-absorption edge were observed and analyzed. The Pd-Pd bonding distance in the fcc Pd lattice was enlarged by 0.08 {approx} 0.09 A during absorption of deuterium, and it completely reverted to its original state with the release of deuterium while maintaining the crystal lattice symmetry. These changes provide evidence that deuterium locates not on the surface of the Pd particle, but rather within the Pd crystal lattice. XANES spectra clearly indicate that any change in the oxidation state of Pd are not observed, resulting in no reaction of the absorbed Deuterium atoms with Pd atoms. This paper reports the alternation of Pd lattice in nano-sized composite during hydrogen absorption. The possible models of deuterium position in the Pd lattice are also discussed.

  2. Investigations of the Absorption Properties of Near-Ground Aerosol by the Methods of Optical-Acoustic Spectrometry and Diff...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Investigations of the Absorption Properties of Near-Ground Aerosol by the Methods of Optical-Acoustic Spectrometry and Diffuse Extinction V. S. Kozlov, M. V. Panchenko, A. B. Tikhomirov, and B. A. Tikhomirov Institute of Atmospheric Optics Tomsk, Russia Introduction Aerosol absorption is an important factor in the formation of non-selective radiation extinction in the visible wavelength range, and plays a great role in solving many radiative and climatic problems. The principal absorbing

  3. H I 21 cm ABSORPTION AND UNIFIED SCHEMES OF ACTIVE GALACTIC NUCLEI

    SciTech Connect (OSTI)

    Curran, S. J.; Whiting, M. T.

    2010-03-20

    In a recent study of z >= 0.1 active galactic nuclei (AGNs), we found that 21 cm absorption has never been detected in objects in which the ultraviolet luminosity exceeds L{sub UV} {approx} 10{sup 23} W Hz{sup -1}. In this paper, we further explore the implications that this has for the currently popular consensus that it is the orientation of the circumnuclear obscuring torus, invoked by unified schemes of AGNs, which determines whether absorption is present along our sight line. The fact that at L{sub UV} {approx}< 10{sup 23} W Hz{sup -1}, both type-1 and type-2 objects exhibit a 50% probability of detection, suggests that this is not the case and that the bias against detection of H I absorption in type-1 objects is due purely to the inclusion of the L{sub UV} {approx}> 10{sup 23} W Hz{sup -1} sources. Similarly, the ultraviolet luminosities can also explain why the presence of 21 cm absorption shows a preference for radio galaxies over quasars and the higher detection rate in compact sources, such as compact steep spectrum or gigahertz peaked spectrum sources, may also be biased by the inclusion of high-luminosity sources. Being comprised of all 21 cm searched sources at z >= 0.1, this is a necessarily heterogeneous sample, the constituents of which have been observed by various instruments. By this same token, however, the dependence on the UV luminosity may be an all encompassing effect, superseding the unified schemes model, although there is the possibility that the exclusive 21 cm non-detections at high UV luminosities could be caused by a bias toward gas-poor ellipticals. Additionally, the high UV fluxes could be sufficiently exciting/ionizing the H I above 21 cm detection thresholds, although the extent to which this is related to the neutral gas deficit in ellipticals is currently unclear. Examining the moderate UV luminosity (L{sub UV} {approx}< 10{sup 23} W Hz{sup -1}) sample further, from the profile widths and offsets from the systemic velocities, we find no discernible differences between the two AGN types. This may suggest that the bulk of the absorption generally occurs in the galactic disk, which must therefore be randomly orientated with respect to the circumnuclear torus. Furthermore, we see no difference in the reddening between the two AGN types, indicating, like the 21 cm absorption, that the orientation of the torus has little bearing on this. We also find a correlation between 21 cm line strength and the optical-near-infrared color, which suggests that the reddening is caused by dust located in the large-scale, H I absorbing disk which intervenes the sight line to the AGN.

  4. Absorption properties of type-II InAs/InAsSb superlattices measured by spectroscopic ellipsometry

    SciTech Connect (OSTI)

    Webster, P. T.; Riordan, N. A.; Liu, S.; Zhang, Y.-H.; Johnson, S. R.; Steenbergen, E. H.

    2015-02-09

    Strain-balanced InAs/InAsSb superlattices offer access to the mid- to long-wavelength infrared region with what is essentially a ternary material system at the GaSb lattice constant. The absorption coefficients of InAs/InAsSb superlattices grown by molecular beam epitaxy on (100)-oriented GaSb substrates are measured at room temperature over the 30 to 800?meV photon energy range using spectroscopic ellipsometry, and the miniband structure of each superlattice is calculated using a Kronig-Penney model. The InAs/InAsSb conduction band offset is used as a fitting parameter to align the calculated superlattice ground state transition energy to the measured absorption onset at room temperature and to the photoluminescence peak energy at low temperature. It is observed that the ground state absorption coefficient and transition strength are proportional to the square of the wavefunction overlap and the ground state absorption coefficient approaches a maximum value of around 5780?cm{sup ?1} as the wavefunction overlap approaches 100%. The absorption analysis of these samples indicates that the optical joint density of states is weakly dependent on the period thickness and Sb content of the superlattice, and that wavefunction overlap is the principal design parameter in terms of obtaining strong absorption in these structures.

  5. Facilely preparation and microwave absorption properties of Fe{sub 3}O{sub 4} nanoparticles

    SciTech Connect (OSTI)

    Wang, Guiqin, E-mail: wanggq@dlut.edu.cn [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116085 (China); Chang, Yongfeng; Wang, Lifang; Liu, Lidong; Liu, Chao [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116085 (China)

    2013-03-15

    Highlights: ? A bran-new method is firstly used to fabricate Fe{sub 3}O{sub 4} nanoparticles. ? The detailed analysis of formation mechanism is discussed. ? The electromagnetic absorption properties are defined. ? The effect of nanometer-sized is considered for the excellent microwave absorption. - Abstract: The Fe{sub 3}O{sub 4} nanoparticles were prepared by a novel wet-chemical method which shows its highly synthesizing efficiency and controllability. A possible formation mechanism was also proposed to explain the synthesizing process. X-ray diffraction (XRD) and transmission electron microscope (TEM) were employed and yielded an examination of an average diameter of 77 nm of the as-synthesized Fe{sub 3}O{sub 4} nanoparticles with face-centered cubic structure. Vibrating sample magnetometer (VSM) and vector network analyzer were employed to measure the magnetic property and electromagnetic parameters of the nanoparticles, then reflection losses (RL (dB)) were calculated in the frequency range of 218 GHz. A large saturation magnetization (72.36 emu/g) and high coercivity (95 Oe) were determined and indicated that the Fe{sub 3}O{sub 4} nanoparticles own strong magnetic performance. Following simulation results showed that the lowest reflection loss of the sample was ?21.2 dB at 5.6 GHz with layer thickness of 6 mm. Effect of nanometer-sized further provided an explanation for the excellent microwave absorption behavior shown by the Fe{sub 3}O{sub 4} nanoparticles.

  6. Advanced cogeneration and absorption chillers potential for service to Navy bases. Final report

    SciTech Connect (OSTI)

    Andrews, J.W.; Butcher, T.A.; Leigh, R.W.; McDonald, R.J.; Pierce, B.L.

    1996-04-01

    The US military uses millions of Btu`s of thermal energy to heat, cool and deliver process thermal energy to buildings on military bases, much of which is transmitted through a pipeline system incorporating thousands of miles of pipe. Much of this pipeline system is in disrepair and is nearing the end of its useful life, and the boilers which supply it are old and often inefficient. In 1993, Brookhaven National Laboratory (BNL) proposed to SERDP a three-year effort to develop advanced systems of coupled diesel cogenerators and absorption chillers which would be particularly useful in providing a continuation of the services now provided by increasingly antiquated district systems. In mid-February, 1995, BNL learned that all subsequent funding for our program had been canceled. BNL staff continued to develop the Program Plan and to adhere to the requirements of the Execution Plan, but began to look for ways in which the work could be made relevant to Navy and DoD energy needs even without the extensive development plan formerly envisioned. The entire program was therefore re-oriented to look for ways in which small scale cogeneration and absorption chilling technologies, available through procurement rather than development, could provide some solutions to the problem of deteriorated district heating systems. The result is, we believe, a striking new approach to the provision of building services on military bases: in many cases, serious study should be made of the possibility that the old district heating system should be removed or abandoned, and small-scale cogenerators and absorption chillers should be installed in each building. In the remainder of this Summary, we develop the rationale behind this concept and summarize our findings concerning the conditions under which this course of action would be advisable and the economic benefits which will accrue if it is followed. The details are developed in the succeeding sections of the report.

  7. X-ray-absorption study of CuBr at high pressure

    SciTech Connect (OSTI)

    Tranquada, J.M.; Ingalls, R.

    1986-09-15

    The x-ray-absorption spectrum of cuprous bromide has been measured as a function of pressure. The x-ray-absorption near-edge structure proved to be an excellent indicator of high-pressure phase transitions in this material. The normalized ''white-line'' peak heights at both the Cu and Br K-italic edges decreased on entering the tetragonal phase and increased in going to the NaCl structure. The zinc-blende to tetragonal phase transition took place over a very narrow pressure range centered at 46 +- 5 kbar. The transformation from the tetragonal to the NaCl structure, on the other hand, showed a broad mixed-phase region, suggesting a nucleation-and-growth mechanism for the transition. The mixed-phase region was centered at 75 +- 6 kbar. No evidence of a phase between the zinc-blende and tetragonal phases was observed, presumably because it does not exist. Analysis of the extended x-ray-absorption fine-structure (EXAFS) clearly showed that there is no change in coordination in going from the zinc-blende to the tetragonal phase although the nearest-neighbor distance increases slightly. A much larger increase in R-italic/sub 1/ occurs at the transition to the NaCl structure, where the coordination increases from 4 to 6. The mean-square deviation in the nearest-neighbor bond length, sigma/sub 1//sup 2/, appears to be a fairly smooth function of nearest-neighbor distance, decreasing (or increasing) as R-italic/sub 1/ decreases (or increases) more or less independent of structure. Evidence from the literature was presented to suggest that the zinc-blende to tetragonal transition in CuBr (and also CuCl) should occur by shear deformation.

  8. PROBING THE INNER REGIONS OF PROTOPLANETARY DISKS WITH CO ABSORPTION LINE SPECTROSCOPY

    SciTech Connect (OSTI)

    McJunkin, Matthew; France, Kevin; Burgh, Eric B.; Brown, Alexander; Herczeg, Gregory J.; Schindhelm, Eric; Brown, Joanna M.

    2013-03-20

    Carbon monoxide (CO) is the most commonly used tracer of molecular gas in the inner regions of protoplanetary disks. CO can be used to constrain the excitation and structure of the circumstellar environment. Absorption line spectroscopy provides an accurate assessment of a single line of sight through the protoplanetary disk system, giving more straightforward estimates of column densities and temperatures than CO and molecular hydrogen (H{sub 2}) emission line studies. We analyze new observations of ultraviolet CO absorption from the Hubble Space Telescope along the sightlines to six classical T Tauri stars. Gas velocities consistent with the stellar velocities, combined with the moderate-to-high disk inclinations, argue against the absorbing CO gas originating in a fast-moving disk wind. We conclude that the far-ultraviolet observations provide a direct measure of the disk atmosphere or possibly a slow disk wind. The CO absorption lines are reproduced by model spectra with column densities in the range N({sup 12}CO) {approx} 10{sup 16}-10{sup 18} cm{sup -2} and N({sup 13}CO) {approx} 10{sup 15}-10{sup 17} cm{sup -2}, rotational temperatures T{sub rot}(CO) {approx} 300-700 K, and Doppler b-values, b {approx} 0.5-1.5 km s{sup -1}. We use these results to constrain the line-of-sight density of the warm molecular gas (n{sub CO} {approx} 70-4000 cm{sup -3}) and put these observations in context with protoplanetary disk models.

  9. Novel insight into the hydrogen absorption mechanism at the Pd(110) surface

    SciTech Connect (OSTI)

    Ohno, Satoshi E-mail: wilde@iis.u-tokyo.ac.jp; Wilde, Markus E-mail: wilde@iis.u-tokyo.ac.jp; Fukutani, Katsuyuki

    2014-04-07

    The microscopic mechanism of low-temperature (80 K < T < 160 K) hydrogen (H) ingress into the H{sub 2} (<2.66 10{sup ?3} Pa) exposed Pd(110) surface is explored by H depth profiling with {sup 15}N nuclear reaction analysis (NRA) and thermal desorption spectroscopy (TDS) with isotope (H, D) labeled surface hydrogen. NRA and TDS reveal two types of absorbed hydrogen states of distinctly different depth distributions. Between 80 K and ?145 K a near-surface hydride phase evolving as the TDS ?{sub 1} feature at 160 K forms, which initially extends only several nanometers into depth. On the other hand, a bulk-absorbed hydrogen state develops between 80 K and ?160 K which gives rise to a characteristic ?{sub 3} TDS feature above 190 K. These two absorbed states are populated at spatially separated surface entrance channels. The near-surface hydride is populated through rapid penetration at minority sites (presumably defects) while the bulk-absorbed state forms at regular terraces with much lower probability per site. In both cases, absorption of gas phase hydrogen transfers pre-adsorbed hydrogen atoms below the surface and replaces them at the chemisorption sites by post-dosed hydrogen in a process that requires much less activation energy (<100 meV) than monatomic diffusion of chemisorbed H atoms into subsurface sites. This small energy barrier suggests that the rate-determining step of the absorption process is either H{sub 2} dissociation on the H-saturated Pd surface or a concerted penetration mechanism, where excess H atoms weakly bound to energetically less favorable adsorption sites stabilize themselves in the chemisorption wells while pre-chemisorbed H atoms simultaneously transit into the subsurface. The peculiarity of absorption at regular Pd(110) terraces in comparison to Pd(111) and Pd(100) is discussed.

  10. X-ray absorption spectroscopy studies of electrochemically deposited thin oxide films.

    SciTech Connect (OSTI)

    Balasubramanian, M.

    1998-06-02

    We have utilized ''in situ'' X-ray Absorption Fine Structure Spectroscopy to investigate the structure and composition of thin oxide films of nickel and iron that have been prepared by electrodeposition on a graphite substrate from aqueous solutions. The films are generally disordered. Structural information has been obtained from the analysis of the data. We also present initial findings on the local structure of heavy metal ions, e.g. Sr and Ce, incorporated into the electrodeposited nickel oxide films. Our results are of importance in a number of technological applications, among them, batteries, fuel cells, electrochromic and ferroelectric materials, corrosion protection, as well as environmental speciation and remediation.

  11. Present knowledge about specific absorption rates inside a human body exposed to radiofrequency electromagnetic fields

    SciTech Connect (OSTI)

    Garn, J.; Gabriel, C.

    1995-02-01

    We have compiled results of scientific investigations about the relationship between external field-strengths and specific absorption rates inside the human body. The data were normalized to SAR-values that form the basis for current safety standards. Results were compared to exposure limits given in these standard. This comparison should serve as a reference for the selection of reliable reference levels for personal protection against thermal effects in radiofrequency electromagnetic fields. The need to measure and monitor ankle/wrist currents to protect some exposed workers is explained. The study has also highlighted a scarcity of dosimetric data at frequencies below 3 MHz. 20 refs., 7 figs.

  12. Recent Advances in SRS on Hydrogen Isotope Separation Using Thermal Cycling Absorption Process

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Xiao, Xin; Sessions, Henry T.; Heung, L. Kit

    2015-02-01

    The recent Thermal Cycling Absorption Process (TCAP) advances at Savannah River Site (SRS) include compressor-free concept for heating/cooling, push and pull separation using an active inverse column, and compact column design. The new developments allow significantly higher throughput and better reliability from 1/10th of the current production system’s footprint while consuming 60% less energy. Various versions are derived in the meantime for external customers to be used in fusion energy projects and medical isotope production.

  13. Results of Self-Absorption Study on the Versapor 3000 Filters for Radioactive Particulate Air Sampling

    SciTech Connect (OSTI)

    Barnett, J. M.; Cullinan, Valerie I.; Barnett, Debra S.; Trang-Le, Truc LT; Bliss, Mary; Greenwood, Lawrence R.; Ballinger, Marcel Y.

    2009-02-17

    Since the mid-1980s, Pacific Northwest National Laboratory (PNNL) has used a value of 0.85 as the correction factor for self absorption of activity for particulate radioactive air samples collected from building exhaust for environmental monitoring. This value accounts for activity that cannot be detected by direct counting of alpha and beta particles. Emissions can be degraded or blocked by filter fibers for particles buried in the filter material or by inactive dust particles collected with the radioactive particles. These filters are used for monitoring air emissions from PNNL stacks for radioactive particles. This paper describes an effort to re-evaluate self-absorption effects in particulate radioactive air sample filters (Versapor 3000, 47 mm diameter) used at PNNL. There were two methods used to characterize the samples. Sixty samples were selected from the archive for acid digestion to compare the radioactivity measured by direct gas-flow proportional counting of filters to the results obtained after acid digestion of the filter and counting again by gas-flow proportional detection. Thirty different sample filters were selected for visible light microscopy to evaluate filter loading and particulate characteristics. Mass-loading effects were also considered. Filter ratios were calculated by dividing the initial counts by the post-digestion counts with the expectation that post-digestion counts would be higher because digestion would expose radioactivity embedded in the filter in addition to that on top of the filter. Contrary to expectations, the post digestion readings were almost always lower than initial readings and averaged approximately half the initial readings for both alpha and beta activity. Before and after digestion readings appeared to be related to each other, but with a low coefficient of determination (R^2) value. The ratios had a wide range of values indicating that this method did not provide sufficient precision to quantify self-absorption effects. The microscopy analysis compares different filter loadings and shows that smaller particle sizes (under 10 micron) can readily be seen on the more lightly loaded filters. At higher loadings, however, the particle size is harder to differentiate. This study provides data on actual stack emission samples showing a range of mass loading conditions and visual evidence of particle size and distribution and also presents the difficulties in quantifying self-absorption effects using actual samples.

  14. A Fern Fatale - X-ray Absorption Spectroscopy Imaging an Arsenic-Loving

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Fern Fern Fatale - X-ray Absorption Spectroscopy Imaging of an Arsenic-Loving Fern For many people, arsenic is synonymous with poison, so it is perhaps a surprise that some plants, such as the fern Pteris vittata (Figure 1) seem to quite deliberately accumulate large amounts of it. What is more, the plant converts it to the most toxic inorganic form known. How does it do this? First some background; while there is some evidence that arsenic is required for health [1], this is debatable. On

  15. Observing heme doming in myoglobin with femtosecond X-ray absorption spectroscopy

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Levantino, M.; Lemke, H. T.; Schirò, G.; Glownia, M.; Cupane, A.; Cammarata, M.

    2015-07-01

    We report time-resolved X-ray absorption measurements after photolysis of carbonmonoxy myoglobin performed at the LCLS X-ray free electron laser with nearly 100 fs (FWHM) time resolution. Data at the Fe K-edge reveal that the photoinduced structural changes at the heme occur in two steps, with a faster (~70 fs) relaxation preceding a slower (~400 fs) one. We tentatively attribute the first relaxation to a structural rearrangement induced by photolysis involving essentially only the heme chromophore and the second relaxation to a residual Fe motion out of the heme plane that is coupled to the displacement of myoglobin F-helix.

  16. Bench-Scale Development of a Hot Carbonate Absorption Process with

    Office of Scientific and Technical Information (OSTI)

    Crystallization-Enabled High Pressure Stripping for Post-Combustion CO{sub 2} Capture (Technical Report) | SciTech Connect High Pressure Stripping for Post-Combustion CO{sub 2} Capture Citation Details In-Document Search Title: Bench-Scale Development of a Hot Carbonate Absorption Process with Crystallization-Enabled High Pressure Stripping for Post-Combustion CO{sub 2} Capture This report summarizes the methodology and preliminary results of a techno-economic analysis on a hot carbonate

  17. Bench-Scale Development of a Hot Carbonate Absorption Process with

    Office of Scientific and Technical Information (OSTI)

    Crystallization-Enabled High-Pressure Stripping for Post-Combustion CO{sub 2} Capture (Technical Report) | SciTech Connect High-Pressure Stripping for Post-Combustion CO{sub 2} Capture Citation Details In-Document Search Title: Bench-Scale Development of a Hot Carbonate Absorption Process with Crystallization-Enabled High-Pressure Stripping for Post-Combustion CO{sub 2} Capture × You are accessing a document from the Department of Energy's (DOE) SciTech Connect. This site is a product of

  18. CNG process, a new approach to physical-absorption acid-gas removal

    SciTech Connect (OSTI)

    Hise, R.E.; Massey, L.G.; Adler, R.J.; Brosilow, C.B.; Gardner, N.C.; Brown, W.R.; Cook, W.J.; Petrik, M.

    1982-01-01

    The CNG acid gas removal process embodies three novel features: (1) scrubbing with liquid carbon dioxide to remove all sulfurous molecules and other trace contaminants; (2) triple-point crystallization of carbon dioxide to concentrate sulfurous molecules and produce pure carbon dioxide; and (3) absorption of carbon dioxide with a slurry of solid carbon dioxide in organic carrier liquid. The CNG process is discussed and contrasted with existing acid gas removal technology as represented by the Benfield, Rectisol, and Selexol acid gas removal processes.

  19. Measurement of Hydrogen Absorption in Ternary Alloys with Volumetric (Sieverts Loop) Techniques

    SciTech Connect (OSTI)

    Aceves, S.

    2015-10-26

    The Sieverts loop is an inexpensive, robust and reliable methodology for calculating hydrogen absorption in materials [1]. In this approach, we start by storing a sample of the material being tested in the volume Vcell (Figure 1) and initiate the process by producing a high vacuum in the system while the material sample is heated to eliminate (most of) the hydrogen and other impurities previously absorbed. The system typically operates isothermally, with the volume Vref at ambient temperature and the sample at a temperature of interest high enough to liquefy the alloy for the current application to nuclear fusion.

  20. Emission and Absorption Spectroscopy of Carbon Arc Plasma during Formation of Carbon Magnetic Encapsulates

    SciTech Connect (OSTI)

    Lange, H.; Labedz, O.; Huczko, A.; Bystrzejewski, M.

    2011-11-29

    Plasma diagnostics of carbon arc discharge under conditions of carbon magnetic encapsulates formation was performed by emission and absorption spectroscopy. Content of C{sub 2} and Fe species, rotational temperatures of excited (d {sup 3} product {sub g}) and non-excited (a {sup 3} product {sub u}) states, and excitation temperatures of a {sup 5}F and a {sup 3}F levels relatively to the a {sup 5}D level of Fe atoms were determined. The results pointed to a non-equilibrium state of carbon arc plasma under prevailing discharge conditions.

  1. Observing heme doming in myoglobin with femtosecond X-ray absorption spectroscopya)

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Levantino, M.; Lemke, H. T.; Schir, G.; Glownia, M.; Cupane, A.; Cammarata, M.

    2015-07-01

    We report time-resolved X-ray absorption measurements after photolysis of carbonmonoxy myoglobin performed at the LCLS X-ray free electron laser with nearly 100 fs (FWHM) time resolution. Data at the Fe K-edge reveal that the photoinduced structural changes at the heme occur in two steps, with a faster (~70 fs) relaxation preceding a slower (~400 fs) one. We tentatively attribute the first relaxation to a structural rearrangement induced by photolysis involving essentially only the heme chromophore and the second relaxation to a residual Fe motion out of the heme plane that is coupled to the displacement of myoglobin F-helix.

  2. Triple-effect absorption refrigeration system with double-condenser coupling

    DOE Patents [OSTI]

    DeVault, Robert C. (Knoxville, TN); Biermann, Wendell J. (Fayetteville, NY)

    1993-01-01

    A triple effect absorption refrigeration system is provided with a double-condenser coupling and a parallel or series circuit for feeding the refrigerant-containing absorbent solution through the high, medium, and low temperature generators utilized in the triple-effect system. The high temperature condenser receiving vaporous refrigerant from the high temperature generator is double coupled to both the medium temperature generator and the low temperature generator to enhance the internal recovery of heat within the system and thereby increase the thermal efficiency thereof.

  3. Triple-effect absorption refrigeration system with double-condenser coupling

    DOE Patents [OSTI]

    DeVault, R.C.; Biermann, W.J.

    1993-04-27

    A triple effect absorption refrigeration system is provided with a double-condenser coupling and a parallel or series circuit for feeding the refrigerant-containing absorbent solution through the high, medium, and low temperature generators utilized in the triple-effect system. The high temperature condenser receiving vaporous refrigerant from the high temperature generator is double coupled to both the medium temperature generator and the low temperature generator to enhance the internal recovery of heat within the system and thereby increase the thermal efficiency thereof.

  4. Visible absorption spectra of crystal violet in supercritical ethane - methanol solution.

    SciTech Connect (OSTI)

    Dimitrijevic, N. M.; Takahashi, K.; Jonah, C. D.; Chemistry

    2002-11-01

    The effects of concentration and mole fraction of methanol in supercritical ethane on the absorption spectra of crystal violet (CV) were examined. Keeping the concentration of CV in the cell constant at 50 {mu}mol l{sup -1}, both the methanol concentration (from 0.4 to 1.2 mol l{sup -1}) and pressure of ethane (from 60 to 150 bar) were varied. The degree of solvation of CV depends both on the mole fraction and concentration of cosolvent. The dimerization of CV was found to decrease with pressure, and with the ratio between methanol and CV concentrations.

  5. Recent Advances in SRS on Hydrogen Isotope Separation Using Thermal Cycling Absorption Process

    SciTech Connect (OSTI)

    Xiao, Xin; Sessions, Henry T.; Heung, L. Kit

    2015-02-01

    The recent Thermal Cycling Absorption Process (TCAP) advances at Savannah River Site (SRS) include compressor-free concept for heating/cooling, push and pull separation using an active inverse column, and compact column design. The new developments allow significantly higher throughput and better reliability from 1/10th of the current production systems footprint while consuming 60% less energy. Various versions are derived in the meantime for external customers to be used in fusion energy projects and medical isotope production.

  6. Experimental investigation for hydrogen and deuterium separation by thermal cycling absorption process

    SciTech Connect (OSTI)

    Guangda, L.; Guoqiang, J.; Cansheng, S.

    1995-10-01

    The Thermal Cycling Absorption Process (TCAP) is a semicontinuous gas chromatographic process for hydrogen isotope separation by which the experiment for hydrogen-deuterium separation has been carried out. The main operating parameters for optimum separation were obtained. On manual operation conditions the concentrations of product and raffinate gas were better than 99.5% simultaneously at a feed rate of 12.0% for a 1:1 hydrogen-deuterium mixture. Besides, TCAP is a good process for trace heavier isotope enriching from hydrogen. The concentration of deuterium can be reduced from 0.5% to less than 50ppm in hydrogen in ten cycles. 5 refs., 4 figs.

  7. High energy resolution five-crystal spectrometer for high quality fluorescence and absorption measurements on an x-ray absorption spectroscopy beamline

    SciTech Connect (OSTI)

    Llorens, Isabelle; Lahera, Eric; Delnet, William; Proux, Olivier; Dermigny, Quentin; Gelebart, Frederic; Morand, Marc; Shukla, Abhay; Bardou, Nathalie; Ulrich, Olivier; and others

    2012-06-15

    Fluorescence detection is classically achieved with a solid state detector (SSD) on x-ray absorption spectroscopy (XAS) beamlines. This kind of detection however presents some limitations related to the limited energy resolution and saturation. Crystal analyzer spectrometers (CAS) based on a Johann-type geometry have been developed to overcome these limitations. We have tested and installed such a system on the BM30B/CRG-FAME XAS beamline at the ESRF dedicated to the structural investigation of very dilute systems in environmental, material and biological sciences. The spectrometer has been designed to be a mobile device for easy integration in multi-purpose hard x-ray synchrotron beamlines or even with a laboratory x-ray source. The CAS allows to collect x-ray photons from a large solid angle with five spherically bent crystals. It will cover a large energy range allowing to probe fluorescence lines characteristic of all the elements from Ca (Z = 20) to U (Z = 92). It provides an energy resolution of 1-2 eV. XAS spectroscopy is the main application of this device even if other spectroscopic techniques (RIXS, XES, XRS, etc.) can be also achieved with it. The performances of the CAS are illustrated by two experiments that are difficult or impossible to perform with SSD and the complementarity of the CAS vs SSD detectors is discussed.

  8. The dependence of C IV broad absorption line properties on accompanying Si IV and Al III absorption: relating quasar-wind ionization levels, kinematics, and column densities

    SciTech Connect (OSTI)

    Filiz Ak, N.; Brandt, W. N.; Schneider, D. P.; Trump, J. R.; Hall, P. B.; Anderson, S. F.; Hamann, F.; Myers, Adam D.; Pris, I.; Petitjean, P.; Ross, Nicholas P.; Shen, Yue; York, Don

    2014-08-20

    We consider how the profile and multi-year variability properties of a large sample of C IV Broad Absorption Line (BAL) troughs change when BALs from Si IV and/or Al III are present at corresponding velocities, indicating that the line of sight intercepts at least some lower ionization gas. We derive a number of observational results for C IV BALs separated according to the presence or absence of accompanying lower ionization transitions, including measurements of composite profile shapes, equivalent width (EW), characteristic velocities, composite variation profiles, and EW variability. We also measure the correlations between EW and fractional-EW variability for C IV, Si IV, and Al III. Our measurements reveal the basic correlated changes between ionization level, kinematics, and column density expected in accretion-disk wind models; e.g., lines of sight including lower ionization material generally show deeper and broader C IV troughs that have smaller minimum velocities and that are less variable. Many C IV BALs with no accompanying Si IV or Al III BALs may have only mild or no saturation.

  9. Total absorption spectroscopy study of ?Rb decay: A major contributor to reactor antineutrino spectrum shape [Total absorption spectroscopy study of ?Rb: A major contributor to reactor antineutrino flux

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Sonzogni, A.; Zakari-Issoufou, A. -A.; Fallot, M.; Porta, A.; Algora, A.; Tain, J. L.; Valencia, E.; Rice, S.; Bui, V. M.; Cormon, S.; et al

    2015-03-09

    The accurate determination of the emitted reactor antineutrino flux is still a major challenge for actual and future neutrino experiments at reactors, especially after the evidence of a disagreement between the measured antineutrino energy spectrum by Double Chooz, Daya Bay, and Reno and calculated antineutrino spectra obtained from the conversion of the unique integral beta spectra measured at the ILL reactor. Using nuclear data to compute reactor antineutrino spectra may help understanding this bias, with the study of the underlying nuclear physics. Summation calculations allow identifying a list of nuclei that contribute importantly to the antineutrino energy spectra emitted aftermorethe fission of ?,?Pu and ?,?U, and whose beta decay properties might deserve new measurements. Among these nuclei, ?Rb exhausts by itself about 16% of of the antineutrino energy spectrum emitted by Pressurized Water Reactors in the 5 to 8 MeV range. In this Letter, we report new Total Absorption Spectroscopy (TAS) results for this important contributor. The obtained beta feeding from ?Rb shows beta intensity unobserved before in the 4.5 to 5.5 MeV energy region and gives a ground state to ground state branch of 87.5 % 3%. These new data induce a dramatic change in recent summation calculations where a 51% GS to GS branch was considered for ?Rb, increasing the summation antineutrino spectrum in the region nearby the observed bias.The new data still have an important impact on other summation calculations in which more recent data were consideredless

  10. Microtopographic characterization of ice-wedge polygon landscape in Barrow, Alaska: a digital map of troughs, rims, centers derived from high resolution (0.25 m) LiDAR data

    SciTech Connect (OSTI)

    Gangodagamage, Chandana; Wullschleger, Stan

    2014-07-03

    The dataset represents microtopographic characterization of the ice-wedge polygon landscape in Barrow, Alaska. Three microtopographic features are delineated using 0.25 m high resolution digital elevation dataset derived from LiDAR. The troughs, rims, and centers are the three categories in this classification scheme. The polygon troughs are the surface expression of the ice-wedges that are in lower elevations than the interior polygon. The elevated shoulders of the polygon interior immediately adjacent to the polygon troughs are the polygon rims for the low center polygons. In case of high center polygons, these features are the topographic highs. In this classification scheme, both topographic highs and rims are considered as polygon rims. The next version of the dataset will include more refined classification scheme including separate classes for rims ad topographic highs. The interior part of the polygon just adjacent to the polygon rims are the polygon centers.

  11. Propagation and absorption of high-intensity femtosecond laser radiation in diamond

    SciTech Connect (OSTI)

    Kononenko, V V; Konov, V I; Gololobov, V M; Zavedeev, E V

    2014-12-31

    Femtosecond interferometry has been used to experimentally study the photoexcitation of the electron subsystem of diamond exposed to femtosecond laser pulses of intensity 10{sup 11} to 10{sup 14} W cm{sup -2}. The carrier concentration has been determined as a function of incident intensity for three harmonics of a Ti : sapphire laser (800, 400 and 266 nm). The results demonstrate that, in a wide range of laser fluences (up to those resulting in surface and bulk graphitisation), a well-defined multiphoton absorption prevails. We have estimated nonlinear absorption coefficients for pulsed radiation at λ = 800 nm (four-photon transition) and at 400 and 266 nm (indirect and direct two-photon transitions, respectively). It has also been shown that, at any considerable path length of a femtosecond pulse in diamond (tens of microns or longer), the laser beam experiences a severe nonlinear transformation, determining the amount of energy absorbed by the lattice, which is important for the development of technology for diamond photostructuring by ultrashort pulses. The competition between wave packet self-focusing and the plasma defocusing effect is examined as a major mechanism governing the propagation of intense laser pulses in diamond. (interaction of laser radiation with matter. laser plasma)

  12. Continuum absorption in the vicinity of the toroidicity-induced Alfvén gap

    SciTech Connect (OSTI)

    Li, M.; Breizman, B. N.; Zheng, L. J.; Chen, Eugene Y.

    2015-12-04

    Excitation of Alfvén modes is commonly viewed as a concern for energetic particle confinement in burning plasmas. The 3.5 MeValpha particles produced by fusion may be affected as well as other fast ions in both present and future devices. Continuum damping of such modes is one of the key factors that determine their excitation thresholds and saturation levels. This work examines the resonant dissipative response of the Alfvén continuum to an oscillating driving current when the driving frequency is slightly outside the edges of the toroidicity-induced spectral gap. The problem is largely motivated by the need to describe the continuum absorption in the frequency sweeping events. Akey element of this problem is the negative interference of the two closely spaced continuum crossing points.Weexplain why the lower and upper edges of the gap can have very different continuum absorption features. Lastly, the difference is associated with an eigenmode whose frequency can be arbitrarily close to the upper edge of the gap whereas the lower edge of the gap is always a finite distance away from the closest eigenmode.

  13. A table-top femtosecond time-resolved soft x-ray transient absorption spectrometer

    SciTech Connect (OSTI)

    Leone, Stephen; Loh, Zhi-Heng; Khalil, Munira; Correa, Raoul E.; Leone, Stephen R.

    2008-05-21

    A laser-based, table-top instrument is constructed to perform femtosecond soft x-ray transient absorption spectroscopy. Ultrashort soft x-ray pulses produced via high-order harmonic generation of the amplified output of a femtosecond Ti:sapphire laser system are used to probe atomic core-level transient absorptions in atoms and molecules. The results provide chemically specific, time-resolved dynamics with sub-50-fs time resolution. In this setup, high-order harmonics generated in a Ne-filled capillary waveguide are refocused by a gold-coated toroidal mirror into the sample gas cell, where the soft x-ray light intersects with an optical pump pulse. The transmitted high-order harmonics are spectrally dispersed with a home-built soft x-ray spectrometer, which consists of a gold-coated toroidal mirror, a uniform-line spaced plane grating, and a soft x-ray CCD camera. The optical layout of the instrument, design of the soft x-ray spectrometer, and spatial and temporal characterization of the high-order harmonics are described. Examples of static and time-resolved photoabsorption spectra collected on this apparatus are presented.

  14. Continuum absorption in the vicinity of the toroidicity-induced Alfvén gap

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Li, M.; Breizman, B. N.; Zheng, L. J.; Chen, Eugene Y.

    2015-12-04

    Excitation of Alfvén modes is commonly viewed as a concern for energetic particle confinement in burning plasmas. The 3.5 MeValpha particles produced by fusion may be affected as well as other fast ions in both present and future devices. Continuum damping of such modes is one of the key factors that determine their excitation thresholds and saturation levels. This work examines the resonant dissipative response of the Alfvén continuum to an oscillating driving current when the driving frequency is slightly outside the edges of the toroidicity-induced spectral gap. The problem is largely motivated by the need to describe the continuummore » absorption in the frequency sweeping events. Akey element of this problem is the negative interference of the two closely spaced continuum crossing points.Weexplain why the lower and upper edges of the gap can have very different continuum absorption features. Lastly, the difference is associated with an eigenmode whose frequency can be arbitrarily close to the upper edge of the gap whereas the lower edge of the gap is always a finite distance away from the closest eigenmode.« less

  15. Efficient Algorithms for Estimating the Absorption Spectrum within Linear Response TDDFT

    SciTech Connect (OSTI)

    Brabec, Jiri; Lin, Lin; Shao, Meiyue; Govind, Niranjan; Yang, Chao; Saad, Yousef; Ng, Esmond

    2015-10-06

    We present two iterative algorithms for approximating the absorption spectrum of molecules within linear response of time-dependent density functional theory (TDDFT) framework. These methods do not attempt to compute eigenvalues or eigenvectors of the linear response matrix. They are designed to approximate the absorption spectrum as a function directly. They take advantage of the special structure of the linear response matrix. Neither method requires the linear response matrix to be constructed explicitly. They only require a procedure that performs the multiplication of the linear response matrix with a vector. These methods can also be easily modified to efficiently estimate the density of states (DOS) of the linear response matrix without computing the eigenvalues of this matrix. We show by computational experiments that the methods proposed in this paper can be much more efficient than methods that are based on the exact diagonalization of the linear response matrix. We show that they can also be more efficient than real-time TDDFT simulations. We compare the pros and cons of these methods in terms of their accuracy as well as their computational and storage cost.

  16. Broadband optical absorption by tunable Mie resonances in silicon nanocone arrays

    SciTech Connect (OSTI)

    Wang, Z. Y.; Zhang, R. J.; Wang, S. Y.; Lu, M.; Chen, X.; Zheng, Y. X.; Chen, L. Y.; Ye, Z.; Wang, C. Z.; Ho, K. M.

    2015-01-15

    Nanostructure arrays such as nanowire, nanopillar, and nanocone arrays have been proposed to be promising antireflection structures for photovoltaic applications due to their great light trapping ability. In this paper, the optical properties of Si nanopillar and nanocone arrays in visible and infrared region were studied by both theoretical calculations and experiments. The results show that the Mie resonance can be continuously tuned across a wide range of wavelength by varying the diameter of the nanopillars. However, Si nanopillar array with uniform diameter exhibits only discrete resonance mode, thus can't achieve a high broadband absorption. On the other hand, the Mie resonance wavelength in a Si nanocone array can vary continuously as the diameters of the cross sections increase from the apex to the base. Therefore Si nanocone arrays can strongly interact with the incident light in the broadband spectrum and the absorbance by Si nanocone arrays is higher than 95% over the wavelength from 300 to 2000 nm. In addition to the Mie resonance, the broadband optical absorption of Si nanocone arrays is also affected by Wood-Rayleigh anomaly effect and metal impurities introduced in the fabrication process.

  17. Study of the absorption coefficient of alpha particles to lower hybrid waves in tokamak

    SciTech Connect (OSTI)

    Wang, Jianbing Zhang, Xianmei Yu, Limin Zhao, Xiang

    2014-02-12

    Part of the energy of the Lower Hybrid (LH) waves may be absorbed by the ? particles via the so-called perpendicular landau damping mechanism, which depends on various parameters of fusion reactors and the LH waves. In this article, we calculate the absorption coefficient ?{sub ?} of LH waves due to ? particles. Results show that, the ?{sub ?} increases with the parallel refraction index n{sub ?} while deceases with increasing the frequency of LH waves ?{sub LH} over a wide range. Higher background plasma temperature and toroidal magnetic field will increase the absorption, and there is a peak value of ?{sub ?} when n{sub e}?810{sup 19}m{sup ?3} for ITER-like scenario. The thermal corrections to the cold plasma dispersion relation will change the damping rate to a certain extent under some specific conditions. We have also evaluated the fraction of LH power absorbed by the alpha particles, ? ? 0.47% and 4.1% for an LH frequency of 5 GHz and 3.7 GHz respectively for ITER-like scenario. This work gives the effective reference for the choice of parameters of future fusion reactors.

  18. CO{sub 2}-philic oligomers as novel solvents for CO{sub 2} absorption

    SciTech Connect (OSTI)

    Miller, Matthew B; Luebke, David R; Enick, Robert M

    2010-01-01

    Desirable properties for an oligomeric CO{sub 2}-capture solvent in an integrated gasification combined cycle (IGCC) plant include high selectivity for CO{sub 2} over H{sub 2} and water, low viscosity, low vapor pressure, low cost, and minimal environmental, health, and safety impacts. The neat solvent viscosity and solubility of CO{sub 2}, measured via bubble-point loci and presented on a pressure−composition diagram (weight basis), and water miscibility in CO{sub 2}-philic solvents have been determined and compared to results obtained with Selexol, a commercial oligomeric CO{sub 2} solvent. The solvents tested include polyethyleneglycol dimethylether (PEGDME), polypropyleneglycol dimethylether (PPGDME), polypropyleneglycol diacetate (PPGDAc), polybutyleneglycol diacetate (PBGDAc), polytetramethyleneetherglycol diacetate (PTMEGDAc), glyceryl triacetate (GTA), polydimethyl siloxane (PDMS), and perfluorpolyether (PFPE) that has a perfluorinated propyleneglycol monomer unit. Overall, PDMS and PPGDME are the best oligomeric solvents tested and exhibit properties that make them very promising alternatives for the selective absorption of CO{sub 2} from a mixed gas stream, especially if the absorption of water is undesirable.

  19. Method and apparatus for determination of temperature, neutron absorption cross section and neutron moderating power

    DOE Patents [OSTI]

    Vagelatos, Nicholas; Steinman, Donald K.; John, Joseph; Young, Jack C.

    1981-01-01

    A nuclear method and apparatus determines the temperature of a medium by injecting fast neutrons into the medium and detecting returning slow neutrons in three first energy ranges by producing three respective detection signals. The detection signals are combined to produce three derived indicia each systematically related to the population of slow neutrons returning from the medium in a respective one of three second energy ranges, specifically exclusively epithermal neutrons, exclusively substantially all thermal neutrons and exclusively a portion of the thermal neutron spectrum. The derived indicia are compared with calibration indicia similarly systematically related to the population of slow neutrons in the same three second energy ranges returning from similarly irradiated calibration media for which the relationships temperature, neutron absorption cross section and neutron moderating power to such calibration indicia are known. The comparison indicates the temperature at which the calibration indicia correspond to the derived indicia and consequently the temperature of the medium. The neutron absorption cross section and moderating power of the medium can be identified at the same time.

  20. Calculation of the spatial resolution in two-photon absorption spectroscopy applied to plasma diagnosis

    SciTech Connect (OSTI)

    Garcia-Lechuga, M.; Fuentes, L. M.; Grtzmacher, K.; Prez, C. Rosa, M. I. de la

    2014-10-07

    We report a detailed characterization of the spatial resolution provided by two-photon absorption spectroscopy suited for plasma diagnosis via the 1S-2S transition of atomic hydrogen for optogalvanic detection and laser induced fluorescence (LIF). A precise knowledge of the spatial resolution is crucial for a correct interpretation of measurements, if the plasma parameters to be analysed undergo strong spatial variations. The present study is based on a novel approach which provides a reliable and realistic determination of the spatial resolution. Measured irradiance distribution of laser beam waists in the overlap volume, provided by a high resolution UV camera, are employed to resolve coupled rate equations accounting for two-photon excitation, fluorescence decay and ionization. The resulting three-dimensional yield distributions reveal in detail the spatial resolution for optogalvanic and LIF detection and related saturation due to depletion. Two-photon absorption profiles broader than the Fourier transform-limited laser bandwidth are also incorporated in the calculations. The approach allows an accurate analysis of the spatial resolution present in recent and future measurements.