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Sample records for raman lidar vertical

  1. 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...

  2. 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

  3. 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.

  4. 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.

  5. 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...

  6. 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 8’x8’x20’ standard shipping container.

  7. 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...

  8. ARM: Temperature Profiles from Raman Lidar at 10-min averaging...

    Office of Scientific and Technical Information (OSTI)

    Temperature Profiles from Raman Lidar at 10-min averaging interval Title: ARM: Temperature Profiles from Raman Lidar at 10-min averaging interval Temperature Profiles from Raman ...

  9. Raman Lidar Receives Improvements

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

    To minimize dirt and dust that interfere with operation and can damage the lidar ... Late this fall, a second laser head will be installed. In the past, component failures in ...

  10. ARM: Temperature Profiles from Raman Lidar at 60-min averaging...

    Office of Scientific and Technical Information (OSTI)

    Citation Details In-Document Search Title: ARM: Temperature Profiles from Raman Lidar at 60-min averaging interval Temperature Profiles from Raman Lidar at 60-min averaging ...

  11. Raman Lidar Measurements of Aerosols and Water Vapor During the...

    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. ... Marina, California Abstract Raman lidar water vapor and aerosol extinction profiles ...

  12. Raman lidar and MPL Measurements during ALIVE

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

    Raman lidar and MPL Measurements during ALIVE Ferrare, Richard NASA Langley Research Center Turner, David University of Wisconsin-Madison Flynn, Connor Pacific Northwest National Laboratory Petty, Diana Pacific Northwest National Laboratory Mendoza, Albert Pacific Northwest National Laboratory Clayton, Marian NASA Langley Research Center Schmid, Beat Bay Area Environmental Research Institute Category: Field Campaigns Analysis of the aerosol and water vapor data collected by the Raman lidar

  13. Doppler Lidar Vertical Velocity Statistics Value-Added Product...

    Office of Scientific and Technical Information (OSTI)

    Citation Details In-Document Search Title: Doppler Lidar Vertical Velocity Statistics ... Facility operates coherent Doppler lidar systems at several sites around the globe. ...

  14. ARM: 10-minute TEMPORARY Raman Lidar: aerosol extinction profiles...

    Office of Scientific and Technical Information (OSTI)

    extinction profiles and aerosol optical thickness, from first Ferrare algorithm Citation Details In-Document Search Title: ARM: 10-minute TEMPORARY Raman Lidar: aerosol extinction ...

  15. 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

  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

    1998-03-01

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

  17. 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

  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

    2004-10-01

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

  19. 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

  20. 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

  1. 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

  2. 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

  3. 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

  4. 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

  5. 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

  6. 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

    2004-10-01

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

  7. 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...

  8. 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

  9. 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

  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

    2010-12-15

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

  11. 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

  12. 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.

  13. Doppler Lidar Vertical Velocity Statistics Value-Added Product

    SciTech Connect (OSTI)

    Newsom, R. K.; Sivaraman, C.; Shippert, T. R.; Riihimaki, L. D.

    2015-07-01

    Accurate height-resolved measurements of higher-order statistical moments of vertical velocity 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.

  14. 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

  15. 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

  16. Atmospheric measurements using a scanning, solar-blind Raman Lidar

    SciTech Connect (OSTI)

    Eichinger, W.E.; Cooper, D.I.; Holtkamp, D.B.; Karl, R.R. Jr.; Quick, C.R.; Tiee, J.J.

    1991-01-01

    The study of the water cycle by Lidar has many applications. Because micro-scale structures can be identified by their water content, the technique offers new opportunities to visualize and study the phenomena. There are applications to many practical problems in agricultural and water management as well as at waste storage sites. Conventional point sensors are limited and are inappropriate for use in complex terrain or varied vegetation and cannot be extrapolated over even modest ranges. To this end, techniques must be developed to measure the variables associated with evapotranspirative processes over large areas and varied surface conditions. A scanning water-Raman Lidar is an ideal tool for this task in that it can measure the water vapor concentration rapidly with high spatial resolution without influencing the measurements by the presence of the sensor. 3 refs., 5 figs., 1 tab.

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

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

    Value-Added Product RK Newsom C Sivaraman SA McFarlane October 2012 DISCLAIMER This ... Raman Lidar Profiles-Temperature (RLPROFTEMP) Value-Added Product RK Newsom C Sivaraman SA ...

  18. 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)

    0 Raman Lidar Profiles Best Estimate Value-Added Product Technical Report R Newsom January 2012 DISCLAIMER This report was prepared as an account of work sponsored by the U.S. ...

  19. Vertical Variability of Aerosols and Water Vapor Over the Southern...

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

    Vertical Variability of Aerosols and Water Vapor Over the Southern Great Plains R. A. ... Abstract We use Raman lidar profiles of water vapor mixing ratio, relative humidity, ...

  20. 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.

  1. Posters Scanning Raman Lidar Measurements of Atmospheric Water Vapor and Aerosols

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

    5 Posters Scanning Raman Lidar Measurements of Atmospheric Water Vapor and Aerosols R. A. Ferrare and K. D. Evans (a) Hughes STX Corporation Lanham, Maryland S. H. Melfi and D. N. Whiteman NASA/Goddard Space Flight Center Greenbelt, Maryland The principal objective of the Department of Energy's (DOE) Atmospheric Radiation Measurement Program (ARM) is to develop a better understanding of the atmospheric radiative balance in order to improve the parameterization of radiative processes in general

  2. 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.

  3. 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

  4. Macrophysical Properties of Tropical Cirrus Clouds from the CALIPSO Satellite and from Ground-based Micropulse and Raman Lidars

    SciTech Connect (OSTI)

    Thorsen, Tyler J.; Fu, Qiang; Comstock, Jennifer M.; Sivaraman, Chitra; Vaughan, Mark A.; Winker, D.; Turner, David D.

    2013-08-27

    Lidar observations of cirrus cloud macrophysical properties over the U.S. Department of Energy Atmospheric Radiation Measurement (ARM) program Darwin, Australia site are compared from the Cloud-Aerosol Lidar and In- frared Pathfinder Satellite Observation (CALIPSO) satellite, the ground-based ARM micropulse lidar (MPL), and the ARM Raman lidar (RL). Comparisons are made using the subset of profiles where the lidar beam is not fully attenuated. Daytime measurements using the RL are shown to be relatively unaffected by the solar background and are therefore suited for checking the validity of diurnal cycles. RL and CALIPSO cloud fraction profiles show good agreement while the MPL detects significantly less cirrus, particularly during the daytime. Both MPL and CALIPSO observations show that cirrus clouds occur less frequently during the day than at night at all altitudes. In contrast, the RL diurnal cy- cle is significantly different than zero only below about 11 km; where it is the opposite sign (i.e. more clouds during the daytime). For cirrus geomet- rical thickness, the MPL and CALIPSO observations agree well and both datasets have signficantly thinner clouds during the daytime than the RL. From the examination of hourly MPL and RL cirrus cloud thickness and through the application of daytime detection limits to all CALIPSO data we find that the decreased MPL and CALIPSO cloud thickness during the daytime is very likely a result of increased daytime noise. This study highlights the vast im- provement the RL provides (compared to the MPL) in the ARM program's ability to observe tropical cirrus clouds as well as a valuable ground-based lidar dataset for the validation of CALIPSO observations and to help im- prove our understanding of tropical cirrus clouds.

  5. LIDAR

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

    LIDAR - 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 Energy Defense Waste Management Programs Advanced Nuclear Energy Nuclear

  6. Lidar Investigations of Aerosol, Cloud, and Boundary Layer Properties Over the ARM ACRF Sites”

    SciTech Connect (OSTI)

    Ferrare, Richard; Turner, David

    2015-01-13

    Project goals; Characterize the aerosol and ice vertical distributions over the ARM NSA site, and in particular to discriminate between elevated aerosol layers and ice clouds in optically thin scattering layers; Characterize the water vapor and aerosol vertical distributions over the ARM Darwin site, how these distributions vary seasonally, and quantify the amount of water vapor and aerosol that is above the boundary layer; Use the high temporal resolution Raman lidar data to examine how aerosol properties vary near clouds; Use the high temporal resolution Raman lidar and Atmospheric Emitted Radiance Interferometer (AERI) data to quantify entrainment in optically thin continental cumulus clouds; and Use the high temporal Raman lidar data to continue to characterize the turbulence within the convective boundary layer and how the turbulence statistics (e.g., variance, skewness) is correlated with larger scale variables predicted by models.

  7. In situ Raman spectroscopy for growth monitoring of vertically aligned multiwall carbon nanotubes in plasma reactor

    SciTech Connect (OSTI)

    Labbaye, T.; Gaillard, M.; Lecas, T.; Kovacevic, E.; Boulmer-Leborgne, Ch.; Guimbretière, G.; Canizarès, A.; Raimboux, N.; Simon, P.; Ammar, M. R.; Strunskus, T.

    2014-11-24

    Portable and highly sensitive Raman setup was associated with a plasma-enhanced chemical vapor deposition reactor enabling in situ growth monitoring of multi-wall carbon nanotubes despite the combination of huge working distance, high growth speed and process temperature and reactive plasma condition. Near Edge X-ray absorption fine structure spectroscopy was used for ex situ sample analysis as a complementary method to in situ Raman spectroscopy. The results confirmed the fact that the “alternating” method developed here can accurately be used for in situ Raman monitoring under reactive plasma condition. The original analytic tool can be of great importance to monitor the characteristics of these nanostructured materials and readily define the ultimate conditions for targeted results.

  8. 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 Energy Defense Waste Management Programs Advanced Nuclear Energy

  9. 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 Energy Defense Waste Management Programs Advanced Nuclear Energy

  10. 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.

  11. 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.

  12. The Vertical Distribution of Aerosols Over the Atmospheric Radiation Measurement Southern Great Plains Site Measured versus Modeled

    SciTech Connect (OSTI)

    Ferrare, R.; Turner, D.D.; Clayton, M.; Guibert, S.; Schulz, M.; Chin, M.

    2005-03-18

    Aerosol extinction profiles measured by the Department of Energy Atmospheric Radiation Measurement (ARM) Climate Research Facility Raman lidar are used to evaluate aerosol extinction profiles and aerosol optical thickness (AOT) simulated by aerosol models as part of the Aerosol module inter- Comparison in global models (AEROCOM) project. This project seeks to diagnose aerosol modules of global models and subsequently identify and eliminate weak components in aerosol modules used for global modeling; AEROCOM activities also include assembling data sets to be used in the evaluations. The AEROCOM average aerosol extinction profiles typically show good agreement with the Raman lidar profiles for altitudes above about 2 km; below 2 km the average model profiles are significantly (30-50%) lower than the Raman lidar profiles. The vertical variability in the average aerosol extinction profiles simulated by these models is less than the variability in the corresponding Raman lidar pro files. The measurements also show a much larger diurnal variability than the Interaction with Chemistry and Aerosols (INCA) model, particularly near the surface where there is a high correlation between aerosol extinction and relative humidity.

  13. 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.

  14. Lidar Report

    SciTech Connect (OSTI)

    Wollpert.

    2009-04-01

    This report provides an overview of the LiDAR acquisition methodology employed by Woolpert on the 2009 USDA - Savannah River LiDAR Site Project. LiDAR system parameters and flight and equipment information is also included. The LiDAR data acquisition was executed in ten sessions from February 21 through final reflights on March 2, 2009; using two Leica ALS50-II 150kHz Multi-pulse enabled LiDAR Systems. Specific details about the ALS50-II systems are included in Section 4 of this report.

  15. ARM - Facility News Article

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

    Upgrades to Raman Lidar Backup Laser Improve Reliability Bookmark and Share The Raman Lidar is an active, ground-based laser remote sensing instrument that measures vertical...

  16. ARM - VAP Product - 10rlprofbe1news

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

    profiles from Raman Lidar Active Dates 2004.10.01 - 2015.09.21 Originating VAP Process Raman LIDAR Vertical Profiles : RLPROF Measurements The measurements below provided by...

  17. 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.

  18. High Spectral Resolution Lidar Data

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

    Eloranta, Ed

    2004-12-01

    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 7.5 meter resolution. Profiles extended from an altitude of 100 m to 30 km in clear air. The lidar penetrated to a maximum optical depth of ~ 4 under cloudy conditions. Our data contributed directly to the aims of the M-PACE experiment, providing calibrated optical depth and optical backscatter measurements which were not available from any other instrument.

  19. 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.

  20. 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

  1. Doppler Lidar Wind Value-Added Product

    SciTech Connect (OSTI)

    Newsom, R. K.; Sivaraman, C.; Shippert, T. R.; Riihimaki, L. D.

    2015-07-01

    Wind speed and direction, together with pressure, temperature, and relative humidity, are the most fundamental atmospheric state parameters. Accurate measurement of these parameters is crucial for numerical weather prediction. Vertically resolved wind measurements in the atmospheric boundary layer are particularly important for modeling pollutant and aerosol transport. Raw data from a scanning coherent Doppler lidar system can be processed to generate accurate height-resolved measurements of wind speed and direction in the atmospheric boundary layer.

  2. Finnish Meteorological Institute Doppler Lidar (Dataset) | Data...

    Office of Scientific and Technical Information (OSTI)

    Finnish Meteorological Institute Doppler Lidar Title: Finnish Meteorological Institute Doppler Lidar This doppler lidar system provides co-polar and cross polar attenuated ...

  3. Evaluation of three lidar scanning strategies for turbulence measurements

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

    Newman, Jennifer F.; Klein, Petra M.; Wharton, Sonia; Sathe, Ameya; Bonin, Timothy A.; Chilson, Phillip B.; Muschinski, Andreas

    2016-05-03

    Several errors occur when a traditional Doppler beam swinging (DBS) or velocity–azimuth 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 some of the errors caused bymore » 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

  4. 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

  5. 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.

  6. 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

  7. 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.

  8. 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

  9. ARM: 10-minute Raman Lidar: aerosol scattering ratio and backscatterin...

    Office of Scientific and Technical Information (OSTI)

    Sponsoring Org: USDOE Office of Science (SC), Biological and Environmental Research (BER) (SC-23) Country of Publication: United States Availability: ORNL Language: English ...

  10. Raman lidar/AERI PBL Height Product (Dataset) | Data Explorer

    Office of Scientific and Technical Information (OSTI)

    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 ...

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

    Office of Scientific and Technical Information (OSTI)

    Authors: Newsom, RK ; Sivaraman, C ; McFarlane, SA Publication Date: 2012-10-31 OSTI Identifier: 1053989 Report Number(s): DOESC-ARMTR-120 PNNL-21965 DOE Contract Number: ...

  12. 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.

  13. 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.

  14. 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 ... DOESC-ARMTR-148 Doppler Lidar Wind Value-Added Product Version 1.0 RK Newsom C Sivaraman ...

  15. ARM - Campaign Instrument - co2lidar

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

    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...

  16. 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.

  17. Cloud properties derived from two lidars over the ARM SGP site

    SciTech Connect (OSTI)

    Dupont, Jean-Charles; Haeffelin, Martial; Morille, Y.; Comstock, Jennifer M.; Flynn, Connor J.; Long, Charles N.; Sivaraman, Chitra; Newsom, Rob K.

    2011-02-16

    [1] Active remote sensors such as lidars or radars can be used with other data to quantify the cloud properties at regional scale and at global scale (Dupont et al., 2009). Relative to radar, lidar remote sensing is sensitive to very thin and high clouds but has a significant limitation due to signal attenuation in the ability to precisely quantify the properties of clouds with a 20 cloud optical thickness larger than 3. In this study, 10-years of backscatter lidar signal data are analysed by a unique algorithm called STRucture of ATmosphere (STRAT, Morille et al., 2007). We apply the STRAT algorithm to data from both the collocated Micropulse lidar (MPL) and a Raman lidar (RL) at the Atmospheric Radiation Measurement (ARM) Southern Great Plains (SGP) site between 1998 and 2009. Raw backscatter lidar signal is processed and 25 corrections for detector deadtime, afterpulse, and overlap are applied. (Campbell et al.) The cloud properties for all levels of clouds are derived and distributions of cloud base height (CBH), top height (CTH), physical cloud thickness (CT), and optical thickness (COT) from local statistics are compared. The goal of this study is (1) to establish a climatology of macrophysical and optical properties for all levels of clouds observed over the ARM SGP site 30 and (2) to estimate the discrepancies induced by the two remote sensing systems (pulse energy, sampling, resolution, etc.). Our first results tend to show that the MPLs, which are the primary ARM lidars, have a distinctly limited range where all of these cloud properties are detectable, especially cloud top and cloud thickness, but even actual cloud base especially during summer daytime period. According to the comparisons between RL and MPL, almost 50% of situations show a signal to noise ratio too low (smaller than 3) for the MPL in order to detect clouds higher than 7km during daytime period in summer. Consequently, the MPLderived annual cycle of cirrus cloud base (top) altitude is

  18. A one-year climatology using data from the Southern Great Plains (SGP) site micropulse lidar

    SciTech Connect (OSTI)

    Mace, G.G.; Ackerman, T.P.; Spinhirne, J.; Scott, S.

    1996-04-01

    The micropulse lidar (MPL) has been operational at the Southern Great Plains (SGP) site of the Atmospheric Radiation Measurement Program for the past 15 months. The compact MPL is unique among research lidar systems in that it is eye-safe and operates continuously, except during precipitation. The MPL is capable of detecting cloud base throughout the entire depth of the troposphere. The MPL data set is an unprecedented time series of cloud heights. It is a vital resource for understanding the frequency of cloud ocurrence and the impact of clouds on the surface radiation budget, as well as for large-scale model validation and satellite retrieval verification. The raw lidar data are processed for cloud base height at a temporal frequency of one minute and a vertical resolution of 270 m. The resultant time series of cloud base is used to generate histograms as a function of month and time of day. Sample results are described.

  19. "Lidar Investigations of Aerosol, Cloud, and Boundary Layer Properties...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: "Lidar Investigations of Aerosol, Cloud, and Boundary Layer Properties Over the ARM ACRF Sites" Citation Details In-Document Search Title: "Lidar Investigations ...

  20. Lidar Inter-Comparison Exercise Final Campaign Report (Program...

    Office of Scientific and Technical Information (OSTI)

    Program Document: Lidar Inter-Comparison Exercise Final Campaign Report Citation Details In-Document Search Title: Lidar Inter-Comparison Exercise Final Campaign Report The ...

  1. Vertical axis wind turbines

    DOE Patents [OSTI]

    Krivcov, Vladimir; Krivospitski, Vladimir; Maksimov, Vasili; Halstead, Richard; Grahov, Jurij

    2011-03-08

    A vertical axis wind turbine is described. The wind turbine can include a top ring, a middle ring and a lower ring, wherein a plurality of vertical airfoils are disposed between the rings. For example, three vertical airfoils can be attached between the upper ring and the middle ring. In addition, three more vertical airfoils can be attached between the lower ring and the middle ring. When wind contacts the vertically arranged airfoils the rings begin to spin. By connecting the rings to a center pole which spins an alternator, electricity can be generated from wind.

  2. ARM - Measurement - Backscattered radiation

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

    : Raman LIDAR Vertical Profiles TWIN-OTTER-LI-PROF : Twin Otter Lidar Profiles UAV-EGRETT : UAV-Egrett UAV-PROTEUS : UAV Proteus UW-CONVAIR580 : University of Washington Convair ...

  3. Observation of Fair-weather Cumuli over Land Dynamical Factors...

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

    state-of-the-art instruments such as the Ka ARM Zenith Radar (KAZR) for cloud thickness, Doppler lidar for clear and cloudy atmosphere vertical velocity, and Raman lidar for...

  4. Quantifying the Effect of Lidar Turbulence Error on Wind Power Prediction

    SciTech Connect (OSTI)

    Newman, Jennifer F.; Clifton, Andrew

    2016-01-01

    Currently, cup anemometers on meteorological towers are used to measure wind speeds and turbulence intensity to make decisions about wind turbine class and site suitability; however, as modern turbine hub heights increase and wind energy expands to complex and remote sites, it becomes more difficult and costly to install meteorological towers at potential sites. As a result, remote-sensing devices (e.g., lidars) are now commonly used by wind farm managers and researchers to estimate the flow field at heights spanned by a turbine. Although lidars can accurately estimate mean wind speeds and wind directions, there is still a large amount of uncertainty surrounding the measurement of turbulence using these devices. Errors in lidar turbulence estimates are caused by a variety of factors, including instrument noise, volume averaging, and variance contamination, in which the magnitude of these factors is highly dependent on measurement height and atmospheric stability. As turbulence has a large impact on wind power production, errors in turbulence measurements will translate into errors in wind power prediction. The impact of using lidars rather than cup anemometers for wind power prediction must be understood if lidars are to be considered a viable alternative to cup anemometers.In this poster, the sensitivity of power prediction error to typical lidar turbulence measurement errors is assessed. Turbulence estimates from a vertically profiling WINDCUBE v2 lidar are compared to high-resolution sonic anemometer measurements at field sites in Oklahoma and Colorado to determine the degree of lidar turbulence error that can be expected under different atmospheric conditions. These errors are then incorporated into a power prediction model to estimate the sensitivity of power prediction error to turbulence measurement error. Power prediction models, including the standard binning method and a random forest method, were developed using data from the aeroelastic simulator FAST

  5. 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.

  6. Vertical Axis Wind Turbine

    Energy Science and Technology Software Center (OSTI)

    2002-04-01

    Blade fatigue life is an important element in determining the economic viability of the Vertical-Axis Wind Turbine (VAWT). VAWT-SAL Vertical Axis Wind Turbine- Stochastic Aerodynamic Loads Ver 3.2 numerically simulates the stochastic (random0 aerodynamic loads of the Vertical-Axis Wind Turbine (VAWT) created by the atomspheric turbulence. The program takes into account the rotor geometry, operating conditions, and assumed turbulence properties.

  7. Vertical Velocity Focus Group

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

    and improving cloud parameterization in global climate models (GCMs) is not straightforward, due to gigantic scale mismatches. Consider this... Looking only vertically...

  8. 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

  9. 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.

  10. 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.

  11. 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

  12. Raman accumulator as a fusion laser driver

    DOE Patents [OSTI]

    George, E. Victor; Swingle, James C.

    1985-01-01

    Apparatus for simultaneous laser pulse amplification and compression, using multiple pass Raman scattering in one Raman cell and pulse switchout from the optical cavity through use of a dichroic device associated with the Raman cell.

  13. Raman accumulator as a fusion laser driver

    DOE Patents [OSTI]

    George, E.V.; Swingle, J.C.

    1982-03-31

    Apparatus for simultaneous laser pulse amplification and compression, using multiple pass Raman scattering in one Raman cell and pulse switchout from the optical cavity through use of a dichroic device associated with the Raman cell.

  14. Micromachined electrostatic vertical actuator

    DOE Patents [OSTI]

    Lee, Abraham P.; Sommargren, Gary E.; McConaghy, Charles F.; Krulevitch, Peter A.

    1999-10-19

    A micromachined vertical actuator utilizing a levitational force, such as in electrostatic comb drives, provides vertical actuation that is relatively linear in actuation for control, and can be readily combined with parallel plate capacitive position sensing for position control. The micromachined electrostatic vertical actuator provides accurate movement in the sub-micron to micron ranges which is desirable in the phase modulation instrument, such as optical phase shifting. For example, compact, inexpensive, and position controllable micromirrors utilizing an electrostatic vertical actuator can replace the large, expensive, and difficult-to-maintain piezoelectric actuators. A thirty pound piezoelectric actuator with corner cube reflectors, as utilized in a phase shifting diffraction interferometer can be replaced with a micromirror and a lens. For any very precise and small amplitudes of motion` micromachined electrostatic actuation may be used because it is the most compact in size, with low power consumption and has more straightforward sensing and control options.

  15. Pressure dependence of Hexanitrostilbene Raman/ electronic absorption...

    Office of Scientific and Technical Information (OSTI)

    Hexanitrostilbene Raman electronic absorption spectra to validate DFT EOS. Citation Details In-Document Search Title: Pressure dependence of Hexanitrostilbene Raman electronic ...

  16. Lidar Inter-Comparison Exercise Final Campaign Report (Program...

    Office of Scientific and Technical Information (OSTI)

    the performance of the new Leosphere R-MAN 510 lidar, procured by the Australian ... To accomplish this evaluation, the R-MAN 510 lidar has been operated at the Darwin ARM ...

  17. Scanning angle Raman spectroscopy: Investigation of Raman scatter enhancement techniques for chemical analysis

    SciTech Connect (OSTI)

    Meyer, Matthew W.

    2013-03-14

    This thesis outlines advancements in Raman scatter enhancement techniques by applying evanescent fields, standing-waves (waveguides) and surface enhancements to increase the generated mean square electric field, which is directly related to the intensity of Raman scattering. These techniques are accomplished by employing scanning angle Raman spectroscopy and surface enhanced Raman spectroscopy. A 1064 nm multichannel Raman spectrometer is discussed for chemical analysis of lignin. Extending dispersive multichannel Raman spectroscopy to 1064 nm reduces the fluorescence interference that can mask the weaker Raman scattering. Overall, these techniques help address the major obstacles in Raman spectroscopy for chemical analysis, which include the inherently weak Raman cross section and susceptibility to fluorescence interference.

  18. Detection of latent prints by Raman imaging

    DOE Patents [OSTI]

    Lewis, Linda Anne; Connatser, Raynella Magdalene; Lewis, Sr., Samuel Arthur

    2011-01-11

    The present invention relates to a method for detecting a print on a surface, the method comprising: (a) contacting the print with a Raman surface-enhancing agent to produce a Raman-enhanced print; and (b) detecting the Raman-enhanced print using a Raman spectroscopic method. The invention is particularly directed to the imaging of latent fingerprints.

  19. SPIE international conference on Raman and luminescence spectroscopy in technology

    SciTech Connect (OSTI)

    Griffiths, J.E.; Adar, F.

    1987-01-01

    These proceedings collect papers on subjects including Raman spectroscopy of semiconductors, Raman and Infrared spectroscopy of thin films, and Raman scattering from tungsten silicide thin films.

  20. 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

  1. 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

  2. Combined Quantum Chemical/Raman Spectroscopic Analyses of Li...

    Office of Scientific and Technical Information (OSTI)

    Language: English Subject: ELECTROLYTES; RAMAN SPECTROSCOPY; CARBONIC ACID ESTERS lithium batteries; electrolyte; solvation number; Raman spectroscopy; ethylene carbonate; ...

  3. Multicolored Vertical Silicon Nanowires

    SciTech Connect (OSTI)

    Seo, Kwanyong; Wober, Munib; Steinvurzel, P.; Schonbrun, E.; Dan, Yaping; Ellenbogen, T.; Crozier, K. B.

    2011-04-13

    We demonstrate that vertical silicon nanowires take on a surprising variety of colors covering the entire visible spectrum, in marked contrast to the gray color of bulk silicon. This effect is readily observable by bright-field microscopy, or even to the naked eye. The reflection spectra of the nanowires each show a dip whose position depends on the nanowire radii. We compare the experimental data to the results of finite difference time domain simulations to elucidate the physical mechanisms behind the phenomena we observe. The nanowires are fabricated as arrays, but the vivid colors arise not from scattering or diffractive effects of the array, but from the guided mode properties of the individual nanowires. Each nanowire can thus define its own color, allowing for complex spatial patterning. We anticipate that the color filter effect we demonstrate could be employed in nanoscale image sensor devices.

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

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

    MPACE Cloud properties derived from the High Spectral Resolution Lidar during MPACE Eloranta, Edwin University of Wisconsin Category: Field Campaigns Cloud properties were derived from data acquired with University of Wisconsin High Spectral Resolution Lidar during its 6-week MPACE deployment. This poster presents statistics on: 1) the altitude and temperature distribution of optical depth and cloud phase. 2) the dependence of lidar depolarization and backscatter phase function on

  5. Quantifying error of lidar and sodar Doppler beam swinging measurements of wind turbine wakes using computational fluid dynamics

    SciTech Connect (OSTI)

    Lundquist, J. K.; Churchfield, M. J.; Lee, S.; Clifton, A.

    2015-02-23

    Wind-profiling lidars are now regularly used in boundary-layer meteorology and in applications such as wind energy and air quality. Lidar wind profilers exploit the Doppler shift of laser light backscattered from particulates carried by the wind to measure a line-of-sight (LOS) velocity. The Doppler beam swinging (DBS) technique, used by many commercial systems, considers measurements of this LOS velocity in multiple radial directions in order to estimate horizontal and vertical winds. The method relies on the assumption of homogeneous flow across the region sampled by the beams. Using such a system in inhomogeneous flow, such as wind turbine wakes or complex terrain, will result in errors.

    To quantify the errors expected from such violation of the assumption of horizontal homogeneity, we simulate inhomogeneous flow in the atmospheric boundary layer, notably stably stratified flow past a wind turbine, with a mean wind speed of 6.5 m s-1 at the turbine hub-height of 80 m. This slightly stable case results in 15° of wind direction change across the turbine rotor disk. The resulting flow field is sampled in the same fashion that a lidar samples the atmosphere with the DBS approach, including the lidar range weighting function, enabling quantification of the error in the DBS observations. The observations from the instruments located upwind have small errors, which are ameliorated with time averaging. However, the downwind observations, particularly within the first two rotor diameters downwind from the wind turbine, suffer from errors due to the heterogeneity of the wind turbine wake. Errors in the stream-wise component of the flow approach 30% of the hub-height inflow wind speed close to the rotor disk. Errors in the cross-stream and vertical velocity components are also significant: cross-stream component errors are on the order of 15% of the hub-height inflow wind speed (1.0 m s−1) and errors in the vertical velocity measurement

  6. Quantifying error of lidar and sodar Doppler beam swinging measurements of wind turbine wakes using computational fluid dynamics

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

    Lundquist, J. K.; Churchfield, M. J.; Lee, S.; Clifton, A.

    2015-02-23

    Wind-profiling lidars are now regularly used in boundary-layer meteorology and in applications such as wind energy and air quality. Lidar wind profilers exploit the Doppler shift of laser light backscattered from particulates carried by the wind to measure a line-of-sight (LOS) velocity. The Doppler beam swinging (DBS) technique, used by many commercial systems, considers measurements of this LOS velocity in multiple radial directions in order to estimate horizontal and vertical winds. The method relies on the assumption of homogeneous flow across the region sampled by the beams. Using such a system in inhomogeneous flow, such as wind turbine wakes ormore » complex terrain, will result in errors. To quantify the errors expected from such violation of the assumption of horizontal homogeneity, we simulate inhomogeneous flow in the atmospheric boundary layer, notably stably stratified flow past a wind turbine, with a mean wind speed of 6.5 m s-1 at the turbine hub-height of 80 m. This slightly stable case results in 15° of wind direction change across the turbine rotor disk. The resulting flow field is sampled in the same fashion that a lidar samples the atmosphere with the DBS approach, including the lidar range weighting function, enabling quantification of the error in the DBS observations. The observations from the instruments located upwind have small errors, which are ameliorated with time averaging. However, the downwind observations, particularly within the first two rotor diameters downwind from the wind turbine, suffer from errors due to the heterogeneity of the wind turbine wake. Errors in the stream-wise component of the flow approach 30% of the hub-height inflow wind speed close to the rotor disk. Errors in the cross-stream and vertical velocity components are also significant: cross-stream component errors are on the order of 15% of the hub-height inflow wind speed (1.0 m s−1) and errors in the vertical velocity measurement exceed the actual

  7. Phase sensitive Raman process with correlated seeds

    SciTech Connect (OSTI)

    Chen, Bing; Qiu, Cheng; Chen, L. Q. Zhang, Kai; Guo, Jinxian; Yuan, Chun-Hua; Zhang, Weiping; Ou, Z. Y.

    2015-03-16

    A phase sensitive Raman scattering was experimentally demonstrated by injecting a Stokes light seed into an atomic ensemble, whose internal state is set in such a way that it is coherent with the input Stokes seed. Such phase sensitive characteristic is a result of interference effect due to the phase correlation between the injected Stokes light field and the internal state of the atomic ensemble in the Raman process. Furthermore, the constructive interference leads to a Raman efficiency larger than other kinds of Raman processes such as stimulated Raman process with Stokes seed injection alone or uncorrelated light-atom seeding. It may find applications in precision spectroscopy, quantum optics, and precise measurement.

  8. ARM - Evaluation Product - MicroPulse LIDAR Cloud Optical Depth...

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

    from the MPLNOR (Micro Pulse Lidar Normalized Backscatter) and radiosonde thermodynamic profiles. The optical depth retrieval is derived following Comstock et al. (2001),...

  9. 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

  10. 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...

  11. 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...

  12. 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...

  13. 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.

  14. Conventional Energy Forum & Associated Vertical Business Development...

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

    Conventional Energy Forum & Associated Vertical Business Development: Best Practices in Indian Country Conventional Energy Forum & Associated Vertical Business Development: Best ...

  15. 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.

  16. 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.

  17. ULTRAVIOLET RAMAN SPECTRAL SIGNATURE ACQUISITION: UV RAMAN SPECTRAL FINGERPRINTS.

    SciTech Connect (OSTI)

    SEDLACEK,III, A.J.FINFROCK,C.

    2002-09-01

    As a member of the science-support part of the ITT-lead LISA development program, BNL is tasked with the acquisition of UV Raman spectral fingerprints and associated scattering cross-sections for those chemicals-of-interest to the program's sponsor. In support of this role, the present report contains the first installment of UV Raman spectral fingerprint data on the initial subset of chemicals. Because of the unique nature associated with the acquisition of spectral fingerprints for use in spectral pattern matching algorithms (i.e., CLS, PLS, ANN) great care has been undertaken to maximize the signal-to-noise and to minimize unnecessary spectral subtractions, in an effort to provide the highest quality spectral fingerprints. This report is divided into 4 sections. The first is an Experimental section that outlines how the Raman spectra are performed. This is then followed by a section on Sample Handling. Following this, the spectral fingerprints are presented in the Results section where the data reduction process is outlined. Finally, a Photographs section is included.

  18. 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

  19. 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.

  20. 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.

  1. 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.

  2. Remote Sensing of Cirrus Particle Size Vertical Profile Using 1.38 μm

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

    Spectrum and MODIS/ARM Data Remote Sensing of Cirrus Particle Size Vertical Profile Using 1.38 μm Spectrum and MODIS/ARM Data Wang, Xingjuan UCLA Department of Atmospheric & Oceanic Sciences Liou, Kuo-Nan UCLA Ou, Szu-cheng University of California, Los Angeles Takano, Yoshihede UCLA Department of Atmospheric & Oceanic Sciences Chen, Yong UCLA Category: Cloud Properties The time series of backscattering coefficients derived from lidar and Doppler millimeter-wave radar returns, as

  3. 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

  4. 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

  5. A generalised background correction algorithm for a Halo Doppler lidar and its application to data from Finland

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

    Manninen, Antti J.; O'Connor, Ewan J.; Vakkari, Ville; Petäjä, Tuukka

    2016-03-03

    Current commercially available Doppler lidars provide an economical and robust solution for measuring vertical and horizontal wind velocities, together with the ability to provide co- and cross-polarised backscatter profiles. The high temporal resolution of these instruments allows turbulent properties to be obtained from studying the variation in radial velocities. However, the instrument specifications mean that certain characteristics, especially the background noise behaviour, become a limiting factor for the instrument sensitivity in regions where the aerosol load is low. Turbulent calculations require an accurate estimate of the contribution from velocity uncertainty estimates, which are directly related to the signal-to-noise ratio. Anymore » bias in the signal-to-noise ratio will propagate through as a bias in turbulent properties. In this paper we present a method to correct for artefacts in the background noise behaviour of commercially available Doppler lidars and reduce the signal-to-noise ratio threshold used to discriminate between noise, and cloud or aerosol signals. Lastly, we show that, for Doppler lidars operating continuously at a number of locations in Finland, the data availability can be increased by as much as 50 % after performing this background correction and subsequent reduction in the threshold. The reduction in bias also greatly improves subsequent calculations of turbulent properties in weak signal regimes.« less

  6. Pressure dependence of Hexanitrostilbene Raman/ electronic absorption...

    Office of Scientific and Technical Information (OSTI)

    in hydrodynamic simulations of the performance of HNS, we have measured the Raman and electronic absorption spectra of this material under static pressure in a diamond anvil cell. ...

  7. Vertical axis wind turbine airfoil

    DOE Patents [OSTI]

    Krivcov, Vladimir; Krivospitski, Vladimir; Maksimov, Vasili; Halstead, Richard; Grahov, Jurij Vasiljevich

    2012-12-18

    A vertical axis wind turbine airfoil is described. The wind turbine airfoil can include a leading edge, a trailing edge, an upper curved surface, a lower curved surface, and a centerline running between the upper surface and the lower surface and from the leading edge to the trailing edge. The airfoil can be configured so that the distance between the centerline and the upper surface is the same as the distance between the centerline and the lower surface at all points along the length of the airfoil. A plurality of such airfoils can be included in a vertical axis wind turbine. These airfoils can be vertically disposed and can rotate about a vertical axis.

  8. ARM - VAP Product - 10rlprofbe1turn

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

    RL & AERI+GOES retrievals Active Dates 1998.03.01 - 2004.01.06 Originating VAP Process Raman LIDAR Vertical Profiles : RLPROF Measurements The measurements below provided by...

  9. Stimulated forward Raman scattering in large scale-length laser...

    Office of Scientific and Technical Information (OSTI)

    Stimulated forward Raman scattering in large scale-length laser-produced plasmas Citation Details In-Document Search Title: Stimulated forward Raman scattering in large ...

  10. Operando Raman and Theoretical Vibration Spectroscopy of Non...

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

    Operando Raman and Theoretical Vibration Spectroscopy of Non-PGM Catalysts Operando Raman and Theoretical Vibration Spectroscopy of Non-PGM Catalysts Presentation about ...

  11. Raman Spectroscopy for Analysis of Thorium Compounds (Conference...

    Office of Scientific and Technical Information (OSTI)

    Conference: Raman Spectroscopy for Analysis of Thorium Compounds Citation Details In-Document Search Title: Raman Spectroscopy for Analysis of Thorium Compounds The thorium fuel ...

  12. Raman spectroscopy in hot compressed hydrogen and nitrogen -...

    Office of Scientific and Technical Information (OSTI)

    Raman spectroscopy in hot compressed hydrogen and nitrogen - implications for the intramolecular potential Citation Details In-Document Search Title: Raman spectroscopy in hot...

  13. Raman and FTIR Studies on Nanostructure Formation on Silicon...

    Office of Scientific and Technical Information (OSTI)

    Raman and FTIR Studies on Nanostructure Formation on Silicon Carbide Citation Details In-Document Search Title: Raman and FTIR Studies on Nanostructure Formation on Silicon Carbide ...

  14. Raman Thermometry of Microdevices: Comparing Methods to Minimize...

    Office of Scientific and Technical Information (OSTI)

    Raman Thermometry of Microdevices: Comparing Methods to Minimize Error. Citation Details In-Document Search Title: Raman Thermometry of Microdevices: Comparing Methods to Minimize...

  15. Raman Thermometry: Comparing Methods to Minimize Error. (Conference...

    Office of Scientific and Technical Information (OSTI)

    Raman Thermometry: Comparing Methods to Minimize Error. Citation Details In-Document Search Title: Raman Thermometry: Comparing Methods to Minimize Error. Abstract not provided....

  16. Q-switched Raman laser system

    DOE Patents [OSTI]

    George, E.V.

    Method and apparatus for use of a Raman or Brillouin switch together with a conventional laser and a saturable absorber that is rapidly bleached at a predeterimined frequency nu = nu/sub O/, to ultimately produce a Raman or Brillouin pulse at frequency nu = nu/sub O/ +- nu /sub Stokes/.

  17. Q-Switched Raman laser system

    DOE Patents [OSTI]

    George, E. Victor

    1985-01-01

    Method and apparatus for use of a Raman or Brillouin switch together with a conventional laser and a saturable absorber that is rapidly bleached at a predetermined frequency .nu.=.nu..sub.0, to ultimately produce a Raman or Brillouin pulse at frequency .nu.=.nu..sub.0 .+-..nu..sub.Stokes.

  18. Development, Field Testing, and Evaluation of LIDAR Assisted Controls

    SciTech Connect (OSTI)

    Ehrmann, Robert; Wang, Na; Scholbrock, Andrew; Guadayol, Marc; Wright, Alan; Arora, Dhiraj

    2015-05-18

    Typical wind turbines utilize feedback controllers which have a delayed response to winds peed disturbances. A nacelle mounted LIght Detection and Ranging(LIDAR) system measures a preview wind signal in front of the turbine. This can be included in a feed-forward control system, improving turbine pitch command for incoming variations in wind speed. The overall aim is reduced blade and tower fatigue, and potentially improved annual energy production. To be successful, the LIDAR must yield accurate wind speed measurements. Therefore, a LIDAR was characterized against a nearby met tower and turbine wind speed estimator. Results indicate good correlation between measurements.

  19. Vertically Aligned Carbon Nanofiber based Biosensor Platform...

    Office of Scientific and Technical Information (OSTI)

    Vertically Aligned Carbon Nanofiber based Biosensor Platform for Glucose Sensor Citation Details In-Document Search Title: Vertically Aligned Carbon Nanofiber based Biosensor ...

  20. Aerosynthesis: Growths of Vertically Aligned Carbon Nanofibers...

    Office of Scientific and Technical Information (OSTI)

    Aerosynthesis: Growths of Vertically Aligned Carbon Nanofibers with Air DC Plasma Citation Details In-Document Search Title: Aerosynthesis: Growths of Vertically Aligned Carbon ...

  1. Multiplex coherent raman spectroscopy detector and method

    DOE Patents [OSTI]

    Chen, Peter; Joyner, Candace C.; Patrick, Sheena T.; Guyer, Dean R.

    2004-06-08

    A multiplex coherent Raman spectrometer (10) and spectroscopy method rapidly detects and identifies individual components of a chemical mixture separated by a separation technique, such as gas chromatography. The spectrometer (10) and method accurately identify a variety of compounds because they produce the entire gas phase vibrational Raman spectrum of the unknown gas. This is accomplished by tilting a Raman cell (20) to produce a high-intensity, backward-stimulated, coherent Raman beam of 683 nm, which drives a degenerate optical parametric oscillator (28) to produce a broadband beam of 1100-1700 nm covering a range of more than 3000 wavenumber. This broadband beam is combined with a narrowband beam of 532 nm having a bandwidth of 0.003 wavenumbers and focused into a heated windowless cell (38) that receives gases separated by a gas chromatograph (40). The Raman radiation scattered from these gases is filtered and sent to a monochromator (50) with multichannel detection.

  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. 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

  4. CVD growth of graphene under exfoliated hexagonal boron nitride for vertical hybrid structures

    SciTech Connect (OSTI)

    Wang, Min; Jang, Sung Kyu; Song, Young Jae; Lee, Sungjoo

    2015-01-15

    Graphical abstract: We have demonstrated a novel yet simple method for fabricating graphene-based vertical hybrid structures by performing the CVD growth of graphene at an h-BN/Cu interface. Our systematic Raman measurements combined with plasma etching process indicate that a graphene film is grown under exfoliated h-BN rather than on its top surface, and that an h-BN/graphene vertical hybrid structure has been fabricated. Electrical transport measurements of this h-BN/graphene, transferred on SiO2, show the carrier mobility up to approximately 2250 cm{sup 2} V{sup ?1} s{sup ?1}. The developed method would enable the exploration of the possibility of novel hybrid structure integration with two-dimensional material systems. - Abstract: We have demonstrated a novel yet simple method for fabricating graphene-based vertical hybrid structures by performing the CVD growth of graphene at an h-BN/Cu interface. Our systematic Raman measurements combined with plasma etching process indicate that a graphene film is grown under exfoliated h-BN rather than on its top surface, and that an h-BN/graphene vertical hybrid structure has been fabricated. Electrical transport measurements of this h-BN/graphene, transferred on SiO{sub 2}, show the carrier mobility up to approximately 2250 cm{sup 2} V{sup ?1} s{sup ?1}. The developed method would enable the exploration of the possibility of novel hybrid structure integration with two-dimensional material systems.

  5. Lidar Inter-Comparison Exercise Final Campaign Report (Technical...

    Office of Scientific and Technical Information (OSTI)

    The objective of this IOP was to evaluate the performances of the new Leosphere R-MAN 510 ... To do so, the R-MAN 510 lidar has been operated at the Darwin ARM site, next to the MPL, ...

  6. 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...

  7. 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: 10.54391177194 What is this? ARM Data Discovery Browse Data Comments? We would love to hear from you Send...

  8. 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

  9. LiDAR Technology | netl.doe.gov

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

    LiDAR Technology LiDAR Technology Enables the Location of Historic Energy Production Sites Understanding the impact that newly developed novel methods for extracting resources from the Earth has on our environment is important, but this requires baseline data against which potential changes can be measured. In Pennsylvania, as in other parts of the United States, commercial activity has already left environmental impacts that are not readily discernible. Charcoal from a completed burn (image

  10. 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.

  11. 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.

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

    SciTech Connect (OSTI)

    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 these 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.

  13. 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

  14. Temperature dependence of sapphire fiber Raman scattering

    SciTech Connect (OSTI)

    Liu, Bo; Yu, Zhihao; Tian, Zhipeng; Homa, Daniel; Hill, Cary; Wang, Anbo; Pickrell, Gary

    2015-04-27

    Anti-Stokes Raman scattering in sapphire fiber has been observed for the first time. Temperature dependence of Raman peaks’ intensity, frequency shift, and linewidth were also measured. Three anti-Stokes Raman peaks were observed at temperatures higher than 300°C in a 0.72-m-long sapphire fiber excited by a second-harmonic Nd YAG laser. The intensity of anti-Stokes peaks are comparable to that of Stokes peaks when the temperature increases to 1033°C. We foresee the combination of sapphire fiber Stokes and anti-Stokes measurement in use as a mechanism for ultrahigh temperature sensing.

  15. Raman spectroscopy at the tritium laboratory Karlsruhe

    SciTech Connect (OSTI)

    Schloesser, M.; Bornschein, B.; Fischer, S.; Kassel, F.; Rupp, S.; Sturm, M.; James, T.M.; Telle, H.H.

    2015-03-15

    Raman spectroscopy is employed successfully for analysis of hydrogen isotopologues at the Tritium Laboratory Karlsruhe (TLK). Raman spectroscopy is based on the inelastic scattering of photons off molecules. Energy is transferred to the molecules as rotational/vibrational excitation being characteristic for each type of molecule. Thus, qualitative analysis is possible from the Raman shifted light, while quantitative information can be obtained from the signal intensities. After years of research and development, the technique is now well-advanced providing fast (< 10 s), precise (< 0.1%) and true (< 3%) compositional analysis of gas mixtures of hydrogen isotopologues. In this paper, we summarize the recent achievements in the further development on this technique, and the various applications for which it is used at TLK. Raman spectroscopy has evolved as a versatile, highly accurate key method for quantitative analysis complementing the port-folio of analytic techniques at the TLK.

  16. 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.

  17. 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...

  18. Vertical tube liquid pollutant separators

    SciTech Connect (OSTI)

    Lynch, W.M.

    1982-06-08

    A plurality of elongated hollow, circular, foraminous substantially vertical tubes contiguously stacked transversely to the direction flowing liquid such as waste water containing foreign matter, I.E., settable solids and free oil, in a coalescer-separator apparatus provide a filter body providing for significant surface area contact by the liquid on both inside and outside surfaces of the tubes to entrap the foreign matter but defining substantially vertical passages permitting the entrapped foreign matter to be gravity separated with the lighter matter coalescing and floating upwardly and the heavier matter settling downwardly so that substantially clarified effluent flows from the apparatus. The stacked tube filter body is contained within an insulated closed container of a sufficient capacity, and the arrays of holes in the tube walls are coordinated with respect to the intended volumetric capacity of the apparatus, so that turbulence in the liquid flowing through the filter body is minimized.

  19. Vertically Integrated Circuits at Fermilab

    SciTech Connect (OSTI)

    Deptuch, Grzegorz; Demarteau, Marcel; Hoff, James; Lipton, Ronald; Shenai, Alpana; Trimpl, Marcel; Yarema, Raymond; Zimmerman, Tom; /Fermilab

    2009-01-01

    The exploration of the vertically integrated circuits, also commonly known as 3D-IC technology, for applications in radiation detection started at Fermilab in 2006. This paper examines the opportunities that vertical integration offers by looking at various 3D designs that have been completed by Fermilab. The emphasis is on opportunities that are presented by through silicon vias (TSV), wafer and circuit thinning and finally fusion bonding techniques to replace conventional bump bonding. Early work by Fermilab has led to an international consortium for the development of 3D-IC circuits for High Energy Physics. The consortium has submitted over 25 different designs for the Fermilab organized MPW run organized for the first time.

  20. FACT SHEET U.S. Department of Energy Eastern North Atlantic

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

    * eddy correlation flux measurement system * disdrometer Lidars * micropulse lidar * Doppler lidar * Raman lidar Radars * zenith cloud radar * scanning cloud radar * scanning...

  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. Tunable infrared source employing Raman mixing

    DOE Patents [OSTI]

    Byer, Robert L.; Herbst, Richard L.

    1980-01-01

    A tunable source of infrared radiation is obtained by irradiating an assemblage of Raman active gaseous atoms or molecules with a high intensity pumping beam of coherent radiation at a pump frequency .omega..sub.p to stimulate the generation of Stokes wave energy at a Stokes frequency .omega..sub.s and to stimulate the Raman resonant mode at the Raman mode frequency .omega..sub.R within the irradiated assemblage where the pump frequency .omega..sub.p minus the Stokes frequency .omega..sub.s is equal to the Raman mode frequency .omega..sub.R. The stimulated assemblage is irradiated with a tunable source of coherent radiation at a frequency .omega..sub.i to generate the output infrared radiation of the frequency .omega..sub.0 which is related to the Raman mode frequency .omega..sub.R and the input wave .omega..sub.i by the relation .omega..sub.0 =.omega..sub.i .+-..omega..sub.R. In one embodiment the interaction between the pump wave energy .omega..sub.p and the tunable input wave energy .omega..sub.i is collinear and the ratio of the phase velocity mismatch factor .DELTA.k to the electric field exponential gain coefficient T is within the range of 0.1 to 5. In another embodiment the pump wave energy .omega..sub.p and the tunable input wave energy .omega..sub.i have velocity vectors k.sub.p and k.sub.i which cross at an angle to each other to compensate for phase velocity mismatches in the medium. In another embodiment, the Stokes wave energy .omega..sub.s is generated by pump energy .omega..sub.p in a first Raman cell and .omega..sub.s, .omega..sub.i and .omega..sub.p are combined in a second Raman mixing cell to produce the output at .omega..sub.i.

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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.

  8. Vertically aligned nanostructure scanning probe microscope tips

    DOE Patents [OSTI]

    Guillorn, Michael A.; Ilic, Bojan; Melechko, Anatoli V.; Merkulov, Vladimir I.; Lowndes, Douglas H.; Simpson, Michael L.

    2006-12-19

    Methods and apparatus are described for cantilever structures that include a vertically aligned nanostructure, especially vertically aligned carbon nanofiber scanning probe microscope tips. An apparatus includes a cantilever structure including a substrate including a cantilever body, that optionally includes a doped layer, and a vertically aligned nanostructure coupled to the cantilever body.

  9. 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

  10. Ultraviolet Resonant Raman Enhancements in the Detection of Explosives

    SciTech Connect (OSTI)

    Short, B J; Carter, J C; Gunter, D; Hovland, P; Jagode, H; Karavanic, K; Marin, G; Mellor-Crummey, J; Moore, S; Norris, B; Oliker, L; Olschanowsky, C; Roth, P C; Schulz, M; Shende, S; Snavely, A; Spear, W

    2009-06-03

    Raman-based spectroscopy is potentially militarily useful for standoff detection of high explosives. Normal (non-resonance) and resonance Raman spectroscopies are both light scattering techniques that use a laser to measure the vibrational spectrum of a sample. In resonance Raman, the laser is tuned to match the wavelength of a strong electronic absorbance in the molecule of interest, whereas, in normal Raman the laser is not tuned to any strong electronic absorbance bands. The selection of appropriate excitation wavelengths in resonance Raman can result in a dramatic increase in the Raman scattering efficiency of select band(s) associated with the electronic transition. Other than the excitation wavelength, however, resonance Raman is performed experimentally the same as normal Raman. In these studies, normal and resonance Raman spectral signatures of select solid high explosive (HE) samples and explosive precursors were collected at 785 nm, 244 nm and 229 nm. Solutions of PETN, TNT, and explosive precursors (DNT & PNT) in acetonitrile solvent as an internal Raman standard were quantitatively evaluated using ultraviolet resonance Raman (UVRR) microscopy and normal Raman spectroscopy as a function of power and select excitation wavelengths. Use of an internal standard allowed resonance enhancements to be estimated at 229 nm and 244 nm. Investigations demonstrated that UVRR provided {approx}2000-fold enhancement at 244 nm and {approx}800-fold improvement at 229 nm while PETN showed a maximum of {approx}25-fold at 244 nm and {approx}190-fold enhancement at 229 nm solely from resonance effects when compared to normal Raman measurements. In addition to the observed resonance enhancements, additional Raman signal enhancements are obtained with ultraviolet excitation (i.e., Raman scattering scales as !4 for measurements based on scattered photons). A model, based partly on the resonance Raman enhancement results for HE solutions, is presented for estimating Raman

  11. Imaging doppler lidar for wind turbine wake profiling

    SciTech Connect (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.

  12. ARM - Field Campaign - Aerosol Lidar Validation Experiment - ALIVE

    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 or call us at 1-888-ARM-DATA. Send Campaign : Aerosol Lidar Validation Experiment - ALIVE 2005.09.12 - 2005.09.22 Website : http://geo.arc.nasa.gov/sgg/ALIVE/index.html Lead Scientist : Beat Schmid For data sets, see below. Abstract We performed the simultaneous validation of aerosol extinction profiles obtained from a

  13. ARM - Field Campaign - Boundary Layer CO2 Using CW Lidar

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

    govCampaignsBoundary Layer CO2 Using CW Lidar Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Boundary Layer CO2 Using CW Lidar 2005.05.21 - 2005.05.24 Lead Scientist : Michael Dobbs Abstract Overflights Underway at ACRF Southern Great Plains Site (M.Dobbs/J.Liljegren) Science collaborators at ITT Industries and the National Aeronautics and Space Administration (NASA) Langley Research Center (LaRC) conducted flights over the Central

  14. 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 Climate Research Cloud Cocktail Melts Greenland Ice Sheet Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : Lidar support for ICECAPS at Summit, Greenland 2010.04.15 - 2018.08.31 Lead Scientist : David Turner Abstract Beginning in May 2010, the Integrated

  15. 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.

  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. Thermal conductivity of vertically aligned carbon nanotube arrays: Growth conditions and tube inhomogeneity

    SciTech Connect (OSTI)

    Bauer, Matthew L.; Pham, Quang N.; Saltonstall, Christopher B.; Norris, Pamela M.

    2014-10-13

    The thermal conductivity of vertically aligned carbon nanotube arrays (VACNTAs) grown on silicon dioxide substrates via chemical vapor deposition is measured using a 3ω technique. For each sample, the VACNTA layer and substrate are pressed to a heating line at varying pressures to extract the sample's thermophysical properties. The nanotubes' structure is observed via transmission electron microscopy and Raman spectroscopy. The presence of hydrogen and water vapor in the fabrication process is tuned to observe the effect on measured thermal properties. The presence of iron catalyst particles within the individual nanotubes prevents the array from achieving the overall thermal conductivity anticipated based on reported measurements of individual nanotubes and the packing density.

  18. Remote adjustable focus Raman spectroscopy probe

    DOE Patents [OSTI]

    Schmucker, John E.; Blasi, Raymond J.; Archer, William B.

    1999-01-01

    A remote adjustable focus Raman spectroscopy probe allows for analyzing Raman scattered light from a point of interest external probe. An environmental barrier including at least one window separates the probe from the point of interest. An optical tube is disposed adjacent to the environmental barrier and includes a long working length compound lens objective next to the window. A beam splitter and a mirror are at the other end. A mechanical means is used to translated the prove body in the X, Y, and Z directions resulting in a variable focus optical apparatus. Laser light is reflected by the beam splitter and directed toward the compound lens objective, then through the window and focused on the point of interest. Raman scattered light is then collected by the compound lens objective and directed through the beam splitter to a mirror. A device for analyzing the light, such as a monochrometer, is coupled to the mirror.

  19. Multistaged stokes injected Raman capillary waveguide amplifier

    DOE Patents [OSTI]

    Kurnit, Norman A.

    1980-01-01

    A multistaged Stokes injected Raman capillary waveguide amplifier for providing a high gain Stokes output signal. The amplifier uses a plurality of optically coupled capillary waveguide amplifiers and one or more regenerative amplifiers to increase Stokes gain to a level sufficient for power amplification. Power amplification is provided by a multifocused Raman gain cell or a large diameter capillary waveguide. An external source of CO.sub.2 laser radiation can be injected into each of the capillary waveguide amplifier stages to increase Raman gain. Devices for injecting external sources of CO.sub.2 radiation include: dichroic mirrors, prisms, gratings and Ge Brewster plates. Alternatively, the CO.sub.2 input radiation to the first stage can be coupled and amplified between successive stages.

  20. First-principles calculations of phonons and Raman spectra in...

    Office of Scientific and Technical Information (OSTI)

    First-principles calculations of phonons and Raman spectra in monoclinic CsSnCl 3 Citation Details In-Document Search Title: First-principles calculations of phonons and Raman ...

  1. Category:Vertical Flowmeter Test | Open Energy Information

    Open Energy Info (EERE)

    Vertical Flowmeter Test Jump to: navigation, search Geothermalpower.jpg Looking for the Vertical Flowmeter Test page? For detailed information on Vertical Flowmeter Test, click...

  2. 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.

  3. Raman laser with controllable suppression of parasitics

    DOE Patents [OSTI]

    George, E. Victor

    1986-01-01

    Method and apparatus for switching energy out of a Raman laser optical cavity. Coherent radiation at both the pump and first Stokes wave frequencies are introduced into the optical cavity from the same direction, and a second Stokes wave is utilized to switch the energy out of the cavity.

  4. Field Raman spectrograph for environmental analysis

    SciTech Connect (OSTI)

    Haas, J.W. III; Forney, R.W.; Carrabba, M.M.

    1995-10-01

    This project entails the development of a compact raman spectrograph for field screening and monitoring of a wide variety of wastes, pollutants, and corrosion products in tanks, and environmental materials. The design of a fiber optic probe for use with the spectrograph is also discussed.

  5. Raman laser with controllable suppression of parasitics

    DOE Patents [OSTI]

    George, E.V.

    Method and apparatus for switching energy out of a Raman laser optical cavity. Coherent radiation at both the pump and first Stokes wave frequencies are introduced into the optical cavity from the same direction, and a second Stokes wave is utilized to switch the energy out of the cavity.

  6. Stokes injected Raman capillary waveguide amplifier

    DOE Patents [OSTI]

    Kurnit, Norman A.

    1980-01-01

    A device for producing stimulated Raman scattering of CO.sub.2 laser radiation by rotational states in a diatomic molecular gas utilizing a Stokes injection signal. The system utilizes a cryogenically cooled waveguide for extending focal interaction length. The waveguide, in conjunction with the Stokes injection signal, reduces required power density of the CO.sub.2 radiation below the breakdown threshold for the diatomic molecular gas. A Fresnel rhomb is employed to circularly polarize the Stokes injection signal and CO.sub.2 laser radiation in opposite circular directions. The device can be employed either as a regenerative oscillator utilizing optical cavity mirrors or as a single pass amplifier. Additionally, a plurality of Raman gain cells can be staged to increase output power magnitude. Also, in the regenerative oscillator embodiment, the Raman gain cell cavity length and CO.sub.2 cavity length can be matched to provide synchronism between mode locked CO.sub.2 pulses and pulses produced within the Raman gain cell.

  7. High Spectral Resolution Infrared and Raman Lidar Observations for the ARM Program: Clear and Cloudy Sky Applications

    SciTech Connect (OSTI)

    Revercomb, Henry; Tobin, David; Knuteson, Robert; Borg, Lori; Moy, Leslie

    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.

  8. 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.

  9. ARM - VAP Process - rlprof

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

    Productsrlprof Documentation & Plots Technical Report Data Management Facility Plots (Quick Looks) 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 VAP : Raman LIDAR Vertical Profiles (RLPROF) Instrument Categories Atmospheric Profiling, Aerosols, Derived Quantities and Models Rlprof data flow diagram Data flowchart for the RLPROF family. (Larger image available.) The Raman lidar automatically attempts to

  10. Single Packaged Vertical Units | Department of Energy

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

    Single Packaged Vertical Units Single Packaged Vertical Units The Department of Energy (DOE) develops standardized data templates for reporting the results of tests conducted in accordance with current DOE test procedures. Templates may be used by third-party laboratories under contract with DOE that conduct testing in support of ENERGY STAR® verification, DOE rulemakings, and enforcement of the federal energy conservation standards. Single Packaged Vertical Units -- v2.0 (103.53 KB) More

  11. Category:Vertical Electrical Sounding Configurations | Open Energy...

    Open Energy Info (EERE)

    Vertical Electrical Sounding Configurations Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermalpower.jpg Looking for the Vertical Electrical Sounding...

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

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

    ... then A-HSRL, better laser * So how does the HSRL compare with the RL? CMWG Breakout Session 2009 ARM Science Team Meeting Strength of Molecular Return in Clear Skies: Raman vs. ...

  13. ARM - Evaluation Product - Convective Vertical Velocity

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

    In particular, vertical air motions associated with these processes are inherently linked to the life cycle of these convective systems and are therefore directly tied to their...

  14. Vertical Flowmeter Logging | Open Energy Information

    Open Energy Info (EERE)

    Logging Jump to: navigation, search OpenEI Reference LibraryAdd to library Web Site: Vertical Flowmeter Logging Author U.S. Geological Survey Published USGS Groundwater...

  15. Vertical Flowmeter Test | Open Energy Information

    Open Energy Info (EERE)

    Test Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Vertical Flowmeter Test Details Activities (0) Areas (0) Regions (0) NEPA(0) Exploration...

  16. Single Packaged Vertical Units | Department of Energy

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

    standards. File Single Packaged Vertical Units -- v2.0 More Documents & Publications Room Air Conditioners Commercial Refrigeration Equipment Commercial Refrigeration Equipment

  17. Vertical Circuits Inc | Open Energy Information

    Open Energy Info (EERE)

    and intellectual property for the manufacture of low cost ultra high-speedhigh-density semiconductor components. References: Vertical Circuits, Inc.1 This article is a...

  18. Combination ring cavity and backward Raman waveguide amplifier

    DOE Patents [OSTI]

    Kurnit, Norman A.

    1983-01-01

    A combination regenerative ring and backward Raman waveguide amplifier and a combination regenerative ring oscillator and backward Raman waveguide amplifier which produce Raman amplification, pulse compression, and efficient energy extraction from the CO.sub.2 laser pump signal for conversion into a Stokes radiation signal. The ring cavity configuration allows the CO.sub.2 laser pump signal and Stokes signal to copropagate through the Raman waveguide amplifier. The backward Raman waveguide amplifier configuration extracts a major portion of the remaining energy from the CO.sub.2 laser pump signal for conversion to Stokes radiation. Additionally, the backward Raman amplifier configuration produces a Stokes radiation signal which has a high intensity and a short duration. Adjustment of the position of overlap of the Stokes signal and the CO.sub.2 laser pump signal in the backward Raman waveguide amplifiers alters the amount of pulse compression which can be achieved.

  19. Vertical two chamber reaction furnace

    DOE Patents [OSTI]

    Blaugher, Richard D.

    1999-03-16

    A vertical two chamber reaction furnace. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium-copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700.degree. and 800.degree. C.) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800.degree. to 950.degree. C. to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product.

  20. Vertical two chamber reaction furnace

    DOE Patents [OSTI]

    Blaugher, R.D.

    1999-03-16

    A vertical two chamber reaction furnace is disclosed. The furnace comprises a lower chamber having an independently operable first heating means for heating the lower chamber and a gas inlet means for admitting a gas to create an ambient atmosphere, and an upper chamber disposed above the lower chamber and having an independently operable second heating means for heating the upper chamber. Disposed between the lower chamber and the upper chamber is a vapor permeable diffusion partition. The upper chamber has a conveyor means for conveying a reactant there through. Of particular importance is the thallinating of long-length thallium-barium-calcium copper oxide (TBCCO) or barium-calcium-copper oxide (BCCO) precursor tapes or wires conveyed through the upper chamber to thereby effectuate the deposition of vaporized thallium (being so vaporized as the first reactant in the lower chamber at a temperature between about 700 and 800 C) on TBCCO or BCCO tape or wire (the second reactant) at its simultaneous annealing temperature in the upper chamber of about 800 to 950 C to thereby replace thallium oxide lost from TBCCO tape or wire because of the high annealing temperature or to deposit thallium on BCCO tape or wire. Continuously moving the tape or wire provides a single-step process that effectuates production of long-length TBCCO superconducting product. 2 figs.

  1. 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.

  2. 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.

  3. 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...

  4. 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...

  5. Doppler Lidar Wind Value-Added Product (Technical Report) | SciTech...

    Office of Scientific and Technical Information (OSTI)

    Wind Value-Added Product Citation Details In-Document Search Title: Doppler Lidar Wind Value-Added Product Wind speed and direction, together with pressure, temperature, and ...

  6. 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...

  7. 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.

  8. Raman spectroscopic investigations of hydrothermal solutions

    SciTech Connect (OSTI)

    Yang, M.M.

    1988-01-01

    There is still very little information about the stoichiometries, structures and stabilities of metal complexes at high temperatures and pressures. Raman spectroscopy is ideally suited to probe and study concentrated electrolyte solutions at the molecular level. This thesis includes the design and construction of a Raman cell operable up to 300C and 15MPa. In order to obtain quantitative thermodynamic information from Raman spectroscopic measurements, a chemically inert internal standard must be used. Perchlorate is commonly used for this purpose at low temperatures, but it may be unstable at high temperatures and its explosive properties make it undesirable. A new preferred internal standard; trifluoromethanesulfonic acid is introduced and its spectra p to 300C discussed. The use of this compound as a high temperature internal standard enabled stepwise stability constants of zinc-bromo complexes to be determined. Although bromide is not an important ligand in geologic systems, its chemical similarity to chloride can provide insights into the study of zinc-chloro species which do not have very informative Raman spectra. The importance of organic ligands in geologic settings such as the Mississippi-Valley Type Pb-Zn sulfide deposits is now being realized. Chapter four presents the first high temperature spectroscopic measurements of lead and zinc acetate aqueous solutions. Not only do these studies verify the stability of lead and zinc acetate complexes up to 250 C but they also show that the type of complex formed is a function of pH, metal-ligand ratio and temperature, thus having important implications for zoning of Pb-Zn sulfide deposits.

  9. Cirrus and aerosol lidar profilometer - analysis and results

    SciTech Connect (OSTI)

    Spinhirne, J.D.; Scott, V.S.; Reagan, J.A.; Galbraith, A.

    1996-04-01

    A cloud and aerosol lidar set from over a year of near continuous operation of a micro pulse lidar (MPL) instrument at the Cloud and Radiation Testbed (CART) site has been established. MPL instruments are to be included in the Ames Research Center (ARC) instrument compliments for the SW Pacific and Arctic ARM sites. Operational processing algorithms are in development for the data sets. The derived products are to be cloud presence and classification, base height, cirrus thickness, cirrus optical thickness, cirrus extinction profile, aerosol optical thickness and profile, and planetary boundary layer (PBL) height. A cloud presence and base height algorithm is in use, and a data set from the CART site is available. The scientific basis for the algorithm development of the higher level data products and plans for implementation are discussed.

  10. 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

  11. 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

  12. 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

  13. 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}.

  14. Tracking Honey Bees Using LIDAR (Light Detection and Ranging) Technology

    SciTech Connect (OSTI)

    BENDER, SUSAN FAE ANN; RODACY, PHILIP J.; SCHMITT, RANDAL L.; HARGIS JR., PHILIP J.; JOHNSON, MARK S.; KLARKOWSKI, JAMES R.; MAGEE, GLEN I.; BENDER, GARY LEE

    2003-01-01

    The Defense Advanced Research Projects Agency (DARPA) has recognized that biological and chemical toxins are a real and growing threat to troops, civilians, and the ecosystem. The Explosives Components Facility at Sandia National Laboratories (SNL) has been working with the University of Montana, the Southwest Research Institute, and other agencies to evaluate the feasibility of directing honeybees to specific targets, and for environmental sampling of biological and chemical ''agents of harm''. Recent work has focused on finding and locating buried landmines and unexploded ordnance (UXO). Tests have demonstrated that honeybees can be trained to efficiently and accurately locate explosive signatures in the environment. However, it is difficult to visually track the bees and determine precisely where the targets are located. Video equipment is not practical due to its limited resolution and range. In addition, it is often unsafe to install such equipment in a field. A technology is needed to provide investigators with the standoff capability to track bees and accurately map the location of the suspected targets. This report documents Light Detection and Ranging (LIDAR) tests that were performed by SNL. These tests have shown that a LIDAR system can be used to track honeybees. The LIDAR system can provide both the range and coordinates of the target so that the location of buried munitions can be accurately mapped for subsequent removal.

  15. Raman-based system for DNA sequencing-mapping and other separations

    DOE Patents [OSTI]

    Vo-Dinh, T.

    1994-04-26

    DNA sequencing and mapping are performed by using a Raman spectrometer with a surface enhanced Raman scattering (SERS) substrate to enhance the Raman signal. A SERS label is attached to a DNA fragment and then analyzed with the Raman spectrometer to identify the DNA fragment according to characteristics of the Raman spectrum generated. 11 figures.

  16. Raman-based system for DNA sequencing-mapping and other separations

    DOE Patents [OSTI]

    Vo-Dinh, Tuan

    1994-01-01

    DNA sequencing and mapping are performed by using a Raman spectrometer with a surface enhanced Raman scattering (SERS) substrate to enhance the Raman signal. A SERS label is attached to a DNA fragment and then analyzed with the Raman spectrometer to identify the DNA fragment according to characteristics of the Raman spectrum generated.

  17. 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

  18. 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

  19. Raman scattering in a whispering mode optical waveguide

    DOE Patents [OSTI]

    Kurnit, Norman A.

    1982-01-01

    A device and method for Raman scattering in a whispering mode optical waveguide. Both a helical ribbon and cylinder are disclosed which incorporate an additional curvature .rho. p for confining the beam to increase intensity. A Raman scattering medium is disposed in the optical path of the beam as it propagates along the waveguide. Raman scattering is enhanced by the high intensities of the beam and long interaction path lengths which are achieved in a small volume.

  20. Resonance Raman Scattering of Rhodamine 6G as Calculated Using...

    Office of Scientific and Technical Information (OSTI)

    Functional Theory Citation Details In-Document Search Title: Resonance Raman Scattering of Rhodamine 6G as Calculated Using Time-Dependent Density Functional Theory The research ...

  1. Two-dimensional stimulated resonance Raman spectroscopy of molecules...

    Office of Scientific and Technical Information (OSTI)

    Two-dimensional stimulated resonance Raman spectroscopy of molecules with broadband x-ray pulses Citation Details In-Document Search Title: Two-dimensional stimulated resonance ...

  2. A SERS Method for Handheld Portable Raman - Energy Innovation...

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

    Technology Marketing Summary Sandia National Laboratories (SNL) has made an initial investment in the research and development of Surface Enhanced Raman hardware capable of being...

  3. Pair breaking versus symmetry breaking: Origin of the Raman modes...

    Office of Scientific and Technical Information (OSTI)

    Pair breaking versus symmetry breaking: Origin of the Raman modes in superconducting cuprates Citation Details In-Document Search Title: Pair breaking versus symmetry breaking:...

  4. Vertical transport and sources in flux models

    SciTech Connect (OSTI)

    Canavan, G.H.

    1997-01-01

    Vertical transport in flux models in examined and shown to reproduce expected limits for densities and fluxes. Disparities with catalog distributions are derived and inverted to find the sources required to rectify them.

  5. Vertically stabilized elongated cross-section tokamak

    DOE Patents [OSTI]

    Sheffield, George V.

    1977-01-01

    This invention provides a vertically stabilized, non-circular (minor) cross-section, toroidal plasma column characterized by an external separatrix. To this end, a specific poloidal coil means is added outside a toroidal plasma column containing an endless plasma current in a tokamak to produce a rectangular cross-section plasma column along the equilibrium axis of the plasma column. By elongating the spacing between the poloidal coil means the plasma cross-section is vertically elongated, while maintaining vertical stability, efficiently to increase the poloidal flux in linear proportion to the plasma cross-section height to achieve a much greater plasma volume than could be achieved with the heretofore known round cross-section plasma columns. Also, vertical stability is enhanced over an elliptical cross-section plasma column, and poloidal magnetic divertors are achieved.

  6. Vertical Pretreatment Reactor System (Poster), NREL (National...

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

    Vertical Pretreatment Reactor System Two-vessel system for primary and secondary ... moves by gravity from top to bottom of reactor in plug-fl ow fashion * Residence time is ...

  7. 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.

  8. Macrophysical and optical properties of midlatitude cirrus clouds from four ground-based lidars and collocated CALIOP observations

    SciTech Connect (OSTI)

    Dupont, Jean-Charles; Haeffelin, M.; Morille, Y.; Noel, V.; Keckhut, P.; Winker, D.; Comstock, Jennifer M.; Chervet, P.; Roblin, A.

    2010-05-27

    Ground-based lidar and CALIOP datasets gathered over four mid-latitude sites, two US and two French sites, are used to evaluate the consistency of cloud macrophysical and optical property climatologies that can be derived by such datasets. The consistency in average cloud height (both base and top height) between the CALIOP and ground datasets ranges from -0.4km to +0.5km. The cloud geometrical thickness distributions vary significantly between the different datasets, due in part to the original vertical resolutions of the lidar profiles. Average cloud geometrical thicknesses vary from 1.2 to 1.9km, i.e. by more than 50%. Cloud optical thickness distributions in subvisible, semi-transparent and moderate intervals differ by more than 50% between ground and space-based datasets. The cirrus clouds with 2 optical thickness below 0.1 (not included in historical cloud climatologies) represent 30-50% of the non-opaque cirrus class. The differences in average cloud base altitude between ground and CALIOP datasets of 0.0-0.1 km, 0.0-0.2 km and 0.0-0.2 km can be attributed to irregular sampling of seasonal variations in the ground-based data, to day-night differences in detection capabilities by CALIOP, and to the restriction to situations without low-level clouds in ground-based data, respectively. The cloud geometrical thicknesses are not affected by irregular sampling of seasonal variations in the ground-based data, while up to 0.0-0.2 km and 0.1-0.3 km differences can be attributed to day-night differences in detection capabilities by CALIOP, and to the restriction to situations without lowlevel clouds in ground-based data, respectively.

  9. Raman beam combining for laser brightness enhancement

    SciTech Connect (OSTI)

    Dawson, Jay W.; Allen, Graham S.; Pax, Paul H.; Heebner, John E.; Sridharan, Arun K.; Rubenchik, Alexander M.; Barty, Chrisopher B. J.

    2015-10-27

    An optical source capable of enhanced scaling of pulse energy and brightness utilizes an ensemble of single-aperture fiber lasers as pump sources, with each such fiber laser operating at acceptable pulse energy levels. Beam combining involves stimulated Raman scattering using a Stokes' shifted seed beam, the latter of which is optimized in terms of its temporal and spectral properties. Beams from fiber lasers can thus be combined to attain pulses with peak energies in excess of the fiber laser self-focusing limit of 4 MW while retaining the advantages of a fiber laser system of high average power with good beam quality.

  10. Raman beam combining for laser brightness enhancement

    DOE Patents [OSTI]

    Dawson, Jay W; Allen, Grahan S; Pax, Paul H; Heebner, John E; Sridharan, Arun K; Rubenchik, Alexander M; Barty, Christopher B.J

    2015-11-05

    An optical source capable of enhanced scaling of pulse energy and brightness utilizes an ensemble of single-aperture fiber lasers as pump sources, with each such fiber laser operating at acceptable pulse energy levels. Beam combining involves stimulated Raman scattering using a Stokes' shifted seed beam, the latter of which is optimized in terms of its temporal and spectral properties. Beams from fiber lasers can thus be combined to attain pulses with peak energies in excess of the fiber laser self-focusing limit of 4 MW while retaining the advantages of a fiber laser system of high average power with good beam quality.

  11. Innovative Offshore Vertical-Axis Wind Turbine Rotors

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

    Offshore Vertical-Axis Wind Turbine Rotors - Sandia Energy Energy Search Icon Sandia Home ... Google + Vimeo Newsletter Signup SlideShare Innovative Offshore Vertical-Axis Wind Turbine ...

  12. Vertical Seismic Profiling At Rye Patch Area (DOE GTP, 2011)...

    Open Energy Info (EERE)

    Vertical Seismic Profiling At Rye Patch Area (DOE GTP, 2011) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Vertical Seismic Profiling At Rye...

  13. Vertical Seismic Profiling At Snake River Plain Region (DOE GTP...

    Open Energy Info (EERE)

    Vertical Seismic Profiling At Snake River Plain Region (DOE GTP) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Vertical Seismic Profiling At...

  14. Herrenknecht Vertical GmbH | Open Energy Information

    Open Energy Info (EERE)

    Specialized company that builds vertical drilling equipment for the development of geothermal resources. References: Herrenknecht Vertical GmbH1 This article is a stub....

  15. Stabilization of the Vertical Mode in Tokamaks by Localized Nonaxisymm...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: Stabilization of the Vertical Mode in Tokamaks by Localized Nonaxisymmetric Fields Citation Details In-Document Search Title: Stabilization of the Vertical Mode in ...

  16. Characterization of uranium tetrafluoride (UF4) with Raman spectroscopy

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

    Villa-Aleman, Eliel; Wellons, Matthew S.

    2016-03-22

    The Raman spectrum of uranium tetrafluoride (UF4) is unambiguously characterized with multiple Raman excitation laser sources for the first time. Across different laser excitation wavelengths, UF4 demonstrates 16 distinct Raman bands within the 50-400 cm-1 region. The observed Raman bands are representative of various F-F vibrational modes. UF4 also shows intense fluorescent bands in the 325 – 750 nm spectral region. Comparison of the UF4 spectrum with the ZrF4 spectrum, its crystalline analog, demonstrates a similar Raman band structure consistent with group theory predictions for expected Raman bands. Additionally, a demonstration of combined scanning electron microscopy (SEM) and in situmore » Raman spectroscopy microanalytical measurements of UF4 particulates shows that despite the inherent weak intensity of Raman bands, identification and characterization are possible for micron-sized particulates with modern instrumentation. The published well characterized UF4 spectrum is extremely relevant to nuclear materials and nuclear safeguard applications.« less

  17. Characterization of uranium tetrafluoride (UF 4 ) with Raman spectroscopy

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

    Villa-Aleman, Eliel; Wellons, Matthew S.

    2016-03-22

    The Raman spectrum of uranium tetrafluoride (UF4) is unambiguously characterized with multiple Raman excitation laser sources for the first time. Across different laser excitation wavelengths, UF4 demonstrates 16 distinct Raman bands within the 50-400 cm-1 region. The observed Raman bands are representative of various F-F vibrational modes. UF4 also shows intense fluorescent bands in the 325 – 750 nm spectral region. Comparison of the UF4 spectrum with the ZrF4 spectrum, its crystalline analog, demonstrates a similar Raman band structure consistent with group theory predictions for expected Raman bands. Additionally, a demonstration of combined scanning electron microscopy (SEM) and in situmore » Raman spectroscopy microanalytical measurements of UF4 particulates shows that despite the inherent weak intensity of Raman bands, identification and characterization are possible for micron-sized particulates with modern instrumentation. The published well characterized UF4 spectrum is extremely relevant to nuclear materials and nuclear safeguard applications.« less

  18. Lidar arc scan uncertainty reduction through scanning geometry optimization

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

    Wang, Hui; Barthelmie, Rebecca J.; Pryor, Sara C.; Brown, Gareth.

    2016-04-13

    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 power performance analysis and annualmore » energy production prediction. 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.« less

  19. Lidar arc scan uncertainty reduction through scanning geometry optimization

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

    Wang, Hui; Barthelmie, Rebecca J.; Pryor, Sara C.; Brown, Gareth.

    2016-04-13

    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 power performance analysis and annualmore » energy production prediction. 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. As a result, large arc spans should be used at sites with high turbulence intensity and/or large wind direction variation.« less

  20. 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

  1. ARM - Measurement - Backscatter depolarization ratio

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

    those recorded for diagnostic or quality assurance purposes. ARM Instruments DL : Doppler Lidar HSRL : High Spectral Resolution Lidar RL : Raman Lidar Field Campaign...

  2. Search for: All records | Data Explorer

    Office of Scientific and Technical Information (OSTI)

    ... Raman Lidar: aerosol scattering ratio and backscattering coefficient profiles, from first Ferrare algorithm Sivaraman, Chitra ; Flynn, Connor 10-minute TEMPORARY Raman Lidar: ...

  3. Search for: All records | Data Explorer

    Office of Scientific and Technical Information (OSTI)

    ARM: Temperature Profiles from Raman Lidar at 10-min averaging interval Chitra Sivaraman ; Connor Flynn Temperature Profiles from Raman Lidar at 10-min averaging interval View ...

  4. Surface enhanced Raman scattering spectroscopic waveguide

    SciTech Connect (OSTI)

    Lascola, Robert J; McWhorter, Christopher S; Murph, Simona H

    2015-04-14

    A waveguide for use with surface-enhanced Raman spectroscopy is provided that includes a base structure with an inner surface that defines a cavity and that has an axis. Multiple molecules of an analyte are capable of being located within the cavity at the same time. A base layer is located on the inner surface of the base structure. The base layer extends in an axial direction along an axial length of an excitation section. Nanoparticles are carried by the base layer and may be uniformly distributed along the entire axial length of the excitation section. A flow cell for introducing analyte and excitation light into the waveguide and a method of applying nanoparticles may also be provided.

  5. Probing non-adiabatic conical intersections using absorption, spontaneous Raman, and femtosecond stimulated Raman spectroscopy

    SciTech Connect (OSTI)

    Patuwo, Michael Y.; Lee, Soo-Y.

    2013-12-21

    We present the time-frame calculated photoabsorption spectrum (ABS), spontaneous Raman excitation profile (REP), femtosecond stimulated Raman spectroscopy (FSRS) spectrum, and femtosecond stimulated Raman excitation profile (FSREP) results of a two-mode and three-mode, three-electronic-states model Hamiltonians containing conical intersections (CIs) along its two upper diabatic electronic states, e{sub 1} (dark) and e{sub 2} (bright), with and without coupling (nonadiabatic dynamics) along an asymmetric mode. For every electronic state in each model, there is one coupling mode and the rest of the modes are symmetric tuning modes. The CI appears in the Hamiltonian as off-diagonal entries to the potential term that couple the two upper states, in the form of a linear function of the coupling mode. We show that: (a) the ABS, REP, and FSREP for Stokes and anti-Stokes lines contain similar information about the e{sub 1} and e{sub 2} vibrational bands, (b) the FSRS spectra feature narrow stationary peaks and broader moving peaks contributed by the different resonant components of the third-order polarization terms from perturbation theory, and (c) a relatively strong and narrow stationary band of the allowed first overtone of the asymmetric coupling mode is observed in the Stokes FSREP in the e{sub 1} energy region with coupling to e{sub 2}.

  6. 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.

  7. 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...

  8. 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.

  9. 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.

  10. Dual optical marker Raman characterization of strained GaN-channels on AlN using AlN/GaN/AlN quantum wells and {sup 15}N isotopes

    SciTech Connect (OSTI)

    Qi, Meng; Li, Guowang; Protasenko, Vladimir; Zhao, Pei; Verma, Jai; Song, Bo; Ganguly, Satyaki; Zhu, Mingda; Hu, Zongyang; Yan, Xiaodong; Xing, Huili Grace; Jena, Debdeep; Mintairov, Alexander

    2015-01-26

    This work shows that the combination of ultrathin highly strained GaN quantum wells embedded in an AlN matrix, with controlled isotopic concentrations of Nitrogen enables a dual marker method for Raman spectroscopy. By combining these techniques, we demonstrate the effectiveness in studying strain in the vertical direction. This technique will enable the precise probing of properties of buried active layers in heterostructures, and can be extended in the future to vertical devices such as those used for optical emitters and for power electronics.

  11. Device and method for noresonantly Raman shifting ultraviolet radiation

    DOE Patents [OSTI]

    Loree, Thomas R.; Barker, Dean L.

    1979-01-01

    A device and method for nonresonantly Raman shifting broad band uv excimer laser radiation, which enhances preselected Stokes signals by varying the pressure of the Raman scattering medium, the focal interaction length of the incident radiation within the Raman scattering medium and its power density level. Gaseous molecular H.sub.2, D.sub.2, CH.sub.4 (methane), HD and mixes thereof, and liquid N.sub.2 are used as the Raman scattering medium to frequency shift the outputs of high power KrF and ArF lasers. A cable fed discharge with an unstable resonant cavity configuration is utilized to produce the output laser power levels required for operation.

  12. Characterization of Gas Shales by X-ray Raman Spectroscopy |...

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

    Characterization of Gas Shales by X-ray Raman Spectroscopy Thursday, February 23, 2012 - 10:30am SSRL Third Floor Conference Room 137-322 Drew Pomerantz, Schlumberger ...

  13. Characterization of Gas Shales by X-ray Raman Spectroscopy |...

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

    Characterization of Gas Shales by X-ray Raman Spectroscopy Monday, May 14, 2012 - 3:30pm SSRL Conference Room 137-322 Drew Pomerantz, Schlumberger Unconventional hydrocarbon ...

  14. Development of coherent Raman measurements of temperature in condensed phases

    SciTech Connect (OSTI)

    Mcgrane, Shawn D; Dang, Nhan C; Bolme, Cindy A; Moore, David S

    2010-12-08

    We report theoretical considerations and preliminary data on various forms of coherent Raman spectroscopy that have been considered as candidates for measurement of temperature in condensed phase experiments with picosecond time resolution. Due to the inherent broadness and congestion of vibrational features in condensed phase solids, particularly at high temperatures and pressures, only approaches that rely on the ratio of anti-Stokes to Stokes spectral features are considered. Methods that rely on resolution of vibrational progressions, calibration of frequency shifts with temperature and pressure in reference experiments, or detailed comparison to calculation are inappropriate or impossible for our applications. In particular, we consider femtosecond stimulated Raman spectroscopy (FSRS), femtosecond/picosecond hybrid coherent Raman spectroscopy (multiplex CARS), and optical heterodyne detected femtosecond Raman induced Kerr Effect spectroscopy (OHD-FRIKES). We show that only FSRS has the ability to measure temperature via an anti-Stokes to Stokes ratio of peaks.

  15. Simulation and visualization of attosecond stimulated x-ray Raman...

    Office of Scientific and Technical Information (OSTI)

    Simulation and visualization of attosecond stimulated x-ray Raman spectroscopy signals in trans-N-methylacetamide at the nitrogen and oxygen K-edges Citation Details In-Document ...

  16. Infrared and Raman Spectroscopy from Ab Initio Molecular Dynamics...

    Office of Scientific and Technical Information (OSTI)

    Infrared and Raman Spectroscopy from Ab Initio Molecular Dynamics and Static Normal Mode Analysis: The C-H Region of DMSO as a Case Study Citation Details In-Document Search Title: ...

  17. Angular output of hollow, metal-lined, waveguide Raman sensors

    SciTech Connect (OSTI)

    Biedrzycki, Stephen; Buric, Michael P.; Falk, Joel; Woodruff, Steven D.

    2012-04-20

    Hollow, metal-lined waveguides used as gas sensors based on spontaneous Raman scattering are capable of large angular collection. The collection of light from a large solid angle implies the collection of a large number of waveguide modes. An accurate estimation of the propagation losses for these modes is required to predict the total collected Raman power. We report a theory/experimental comparison of the Raman power collected as a function of the solid angle and waveguide length. New theoretical observations are compared with previous theory appropriate only for low-order modes. A cutback experiment is demonstrated to verify the validity of either theory. The angular distribution of Raman light is measured using aluminum and silver-lined waveguides of varying lengths.

  18. Stimulated forward Raman scattering in large scale-length laser...

    Office of Scientific and Technical Information (OSTI)

    in large scale-length laser-produced plasmas Citation Details In-Document Search Title: Stimulated forward Raman scattering in large scale-length laser-produced plasmas You ...

  19. 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.

  20. 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.

  1. Surface-enhanced Raman scattering (SERS) dosimeter and probe

    DOE Patents [OSTI]

    Vo-Dinh, Tuan

    1995-01-01

    A dosimeter and probe for measuring exposure to chemical and biological compounds is disclosed. The dosimeter or probe includes a collector which may be analyzed by surface-enhanced Raman spectroscopy. The collector comprises a surface-enhanced Raman scattering-active material having a coating applied thereto to improve the adsorption properties of the collector. The collector may also be used in automated sequential devises, in probe array devices.

  2. Surface-enhanced Raman scattering (SERS) dosimeter and probe

    DOE Patents [OSTI]

    Vo-Dinh, T.

    1995-03-21

    A dosimeter and probe for measuring exposure to chemical and biological compounds is disclosed. The dosimeter or probe includes a collector which may be analyzed by surface-enhanced Raman spectroscopy. The collector comprises a surface-enhanced Raman scattering-active material having a coating applied thereto to improve the adsorption properties of the collector. The collector may also be used in automated sequential devices, in probe array devices. 10 figures.

  3. 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.

  4. Polarized Raman scattering of single ZnO nanorod

    SciTech Connect (OSTI)

    Yu, J. L. Lai, Y. F. Wang, Y. Z.; Cheng, S. Y.

    2014-01-21

    Polarized Raman scattering measurement on single wurtzite c-plane (001) ZnO nanorod grown by hydrothermal method has been performed at room temperature. The polarization dependence of the intensity of the Raman scattering for the phonon modes A{sub 1}(TO), E{sub 1}(TO), and E{sub 2}{sup high} in the ZnO nanorod are obtained. The deviations of polarization-dependent Raman spectroscopy from the prediction of Raman selection rules are observed, which can be attributed to the structure defects in the ZnO nanorod as confirmed by the comparison of the transmission electron microscopy, photoluminescence spectra as well as the polarization dependent Raman signal of the annealed and unannealed ZnO nanorod. The Raman tensor elements of A{sub 1}(TO) and E{sub 1}(TO) phonon modes normalized to that of the E{sub 2}{sup high} phonon mode are |a/d|=0.32±0.01, |b/d|=0.49±0.02, and |c/d|=0.23±0.01 for the unannealed ZnO nanorod, and |a/d|=0.33±0.01, |b/d|=0.45±0.01, and |c/d|=0.20±0.01 for the annealed ZnO nanorod, which shows strong anisotropy compared to that of bulk ZnO epilayer.

  5. Controllable Raman soliton self-frequency shift in nonlinear metamaterials

    SciTech Connect (OSTI)

    Xiang Yuanjiang; Wen Shuangchun; Guo Jun; Fan Dianyuan

    2011-09-15

    Controllable and dispersive magnetic permeability in the metamaterials (MMs) provides us more freedom to harness the propagation of ultrashort electromagnetic pulses at will. Here we discuss the controllability of the Raman soliton self-frequency shift (SSFS) in the MMs with a nonlinear electric polarization. First, we derive a generalized nonlinear Schroedinger equation suitable for few-cycle pulse propagation in the MMs with delayed Raman response, and demonstrate the Raman effect, high-order Raman-related nonlinearity, and high-order nonlinear dispersion terms occurring in this equation. Second, we present a theoretical investigation on the controllability of the Raman SSFS in the MMs. In particular, we identify the combined effects of the anomalous self-steepening (SS), third-order dispersion (TOD), and Raman effect on SSFS. It is shown that the positive SS effect suppresses SSFS; however, the negative SS effect enhances SSFS, and the positive TOD leads to the deceleration of SSFS. Finally, the effects of SS on the SSFS of the second-order soliton are also discussed.

  6. Electrically floating, near vertical incidence, skywave antenna

    DOE Patents [OSTI]

    Anderson, Allen A.; Kaser, Timothy G.; Tremblay, Paul A.; Mays, Belva L.

    2014-07-08

    An Electrically Floating, Near Vertical Incidence, Skywave (NVIS) Antenna comprising an antenna element, a floating ground element, and a grounding element. At least part of said floating ground element is positioned between said antenna element and said grounding element. The antenna is separated from the floating ground element and the grounding element by one or more electrical insulators. The floating ground element is separated from said antenna and said grounding element by one or more electrical insulators.

  7. 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.

  8. ARM - Evaluation Product - Vertical Air Motion during Large-Scale...

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

    ProductsVertical Air Motion during Large-Scale Stratiform Rain ARM Data Discovery Browse ... Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : Vertical Air ...

  9. Offshore Ambitions for the Vertical-Axis Wind Turbine

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

    Ambitions for the Vertical-Axis Wind Turbine - Sandia Energy Energy Search Icon Sandia ... Offshore Ambitions for the Vertical-Axis Wind Turbine HomeEnergy, News, News & Events, ...

  10. The CU 2-D-MAX-DOAS instrument – Part 2: Raman scattering probability measurements and retrieval of aerosol optical properties

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

    Ortega, Ivan; Coburn, Sean; Berg, Larry K.; Lantz, Kathy; Michalsky, Joseph; Ferrare, Richard A.; Hair, Johnathan W.; Hostetler, Chris A.; Volkamer, Rainer

    2016-08-23

    The multiannual global mean of aerosol optical depth at 550 nm (AOD550) over land is ∼ 0.19, and that over oceans is ∼ 0.13. About 45 % of the Earth surface shows AOD550 smaller than 0.1. There is a need for measurement techniques that are optimized to measure aerosol optical properties under low AOD conditions. We present an inherently calibrated retrieval (i.e., no need for radiance calibration) to simultaneously measure AOD and the aerosol phase function parameter, g, based on measurements of azimuth distributions of the Raman scattering probability (RSP), the near-absolute rotational Raman scattering (RRS) intensity. We employ radiative transfer model simulations tomore » show that for solar azimuth RSP measurements at solar elevation and solar zenith angle (SZA) smaller than 80°, RSP is insensitive to the vertical distribution of aerosols and maximally sensitive to changes in AOD and g under near-molecular scattering conditions. The University of Colorado two-dimensional Multi-AXis Differential Optical Absorption Spectroscopy (CU 2-D-MAX-DOAS) instrument was deployed as part of the Two Column Aerosol Project (TCAP) at Cape Cod, MA, during the summer of 2012 to measure direct sun spectra and RSP from scattered light spectra at solar relative azimuth angles (SRAAs) between 5 and 170°. During two case study days with (1) high aerosol load (17 July, 0.3  <  AOD430 < 0.6) and (2) near-molecular scattering conditions (22 July, AOD430 < 0.13) we compare RSP-based retrievals of AOD430 and g with data from a co-located CIMEL sun photometer, Multi-Filter Rotating Shadowband Radiometer (MFRSR), and an airborne High Spectral Resolution Lidar (HSRL-2). The average difference (relative to DOAS) for AOD430 is +0.012 ± 0.023 (CIMEL), −0.012 ± 0.024 (MFRSR), −0.011 ± 0.014 (HSRL-2), and +0.023 ± 0.013 (CIMELAOD − MFRSRAOD) and yields the following expressions for correlations between different instruments

  11. ISSUANCE 2015-8-28: Energy Conservation Program: Energy Conservation Standards for Single Package Vertical Air Conditioners and Single Package Vertical Heat Pumps, Final Rule

    Broader source: Energy.gov [DOE]

    Energy Conservation Program: Energy Conservation Standards for Single Package Vertical Air Conditioners and Single Package Vertical Heat Pumps, Final Rule

  12. Microsoft PowerPoint - illinghogan_mar04.html

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

    observations of clouds and radiation at Chilbolton UK to evaluate NWP models. Anthony Illingworth and Robin Hogan University of Reading, UK * Chilbolton 24h/7d vertical profiles of clouds * 94GHz radar and lidar - profiles 30sec/60m resolution. * Infer cloud properties and compare with values held in operational models for Chilbolton grid box. * 35GHz radar, 22/28/38GHz Radiometers, Raman lidar. * 1275 clear air radar - boundary layer + refractivity * 3GHz polarisation radar for precipitation.

  13. 1

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

    Cirrus Extinction and Lidar Ratio Derived from Raman Lidar Measurements at the Atmospheric Radiation Measurement Program Southern Site D. Petty and J. Comstock Pacific Northwest National Laboratory Richland, Washington D. Tuner Space Science Engineering Center, University of Wisconsin-Madison Madison, Wisconsin Introduction Range resolved microphysical properties and extinction coefficient in cirrus clouds are critical for assessing the impact of cirrus on climate. Vertical profiles of cirrus

  14. Vertical deformation at western part of Sumatra

    SciTech Connect (OSTI)

    Febriyani, Caroline Prijatna, Kosasih Meilano, Irwan

    2015-04-24

    This research tries to make advancement in GPS signal processing to estimate the interseismic vertical deformation field at western part of Sumatra Island. The data derived by Continuous Global Positioning System (CGPS) from Badan Informasi Geospasial (BIG) between 2010 and 2012. GPS Analyze at Massachusetts Institute of Technology (GAMIT) software and Global Kalman Filter (GLOBK) software are used to process the GPS signal to estimate the vertical velocities of the CGPS station. In order to minimize noise due to atmospheric delay, Vienna Mapping Function 1 (VMF1) is used as atmospheric parameter model and include daily IONEX file provided by the Center for Orbit Determination in Europe (CODE) as well. It improves GAMIT daily position accuracy up to 0.8 mm. In a second step of processing, the GLOBK is used in order to estimate site positions and velocities in the ITRF08 reference frame. The result shows that the uncertainties of estimated displacement velocity at all CGPS stations are smaller than 1.5 mm/yr. The subsided deformation patterns are seen at the northern and southern part of west Sumatra. The vertical deformation at northern part of west Sumatra indicates postseismic phase associated with the 2010 and 2012 Northern Sumatra earthquakes and also the long-term postseismic associated with the 2004 and 2005 Northern Sumatra earthquakes. The uplifted deformation patterns are seen from Bukit Tinggi to Seblat which indicate a long-term interseismic phase after the 2007 Bengkulu earthquake and 2010 Mentawai earthquake. GANO station shows a subsidence at rate 12.25 mm/yr, indicating the overriding Indo-Australia Plate which is dragged down by the subducting Southeast Asian Plate.

  15. Experimental comparison of retrofit vertical air collectors

    SciTech Connect (OSTI)

    Wilson, A.T.; Stickney, B.L.

    1980-01-01

    Two vertical air collector systems were built and monitored. One of these is a back-pass collector in which a layer of sheet metal serves as the absorber plate. The other is a front pass collector in which the wall surface serves as the absorber plate. The results demonstrate the importance of considering heat moving through walls even when storage of heat in the wall is of limited significance. With poorly insulated walls, heat is better able to move through the wall with a front pass collector, indicating that this type of collector is a more effective heating system.

  16. Long wavelength vertical cavity surface emitting laser

    DOE Patents [OSTI]

    Choquette, Kent D.; Klem, John F.

    2005-08-16

    Selectively oxidized vertical cavity lasers emitting near 1300 nm using InGaAsN quantum wells are reported for the first time which operate continuous wave below, at and above room temperature. The lasers employ two n-type Al.sub.0.94 Ga.sub.0.06 As/GaAs distributed Bragg reflectors each with a selectively oxidized current aperture adjacent to the active region, and the top output mirror contains a tunnel junction to inject holes into the active region. Continuous wave single mode lasing is observed up to 55.degree. C.

  17. Error and uncertainty in Raman thermal conductivity measurements

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

    Thomas Edwin Beechem; Yates, Luke; Graham, Samuel

    2015-04-22

    We investigated error and uncertainty in Raman thermal conductivity measurements via finite element based numerical simulation of two geometries often employed -- Joule-heating of a wire and laser-heating of a suspended wafer. Using this methodology, the accuracy and precision of the Raman-derived thermal conductivity are shown to depend on (1) assumptions within the analytical model used in the deduction of thermal conductivity, (2) uncertainty in the quantification of heat flux and temperature, and (3) the evolution of thermomechanical stress during testing. Apart from the influence of stress, errors of 5% coupled with uncertainties of ±15% are achievable for most materialsmore » under conditions typical of Raman thermometry experiments. Error can increase to >20%, however, for materials having highly temperature dependent thermal conductivities or, in some materials, when thermomechanical stress develops concurrent with the heating. A dimensionless parameter -- termed the Raman stress factor -- is derived to identify when stress effects will induce large levels of error. Together, the results compare the utility of Raman based conductivity measurements relative to more established techniques while at the same time identifying situations where its use is most efficacious.« less

  18. Low vibration high numerical aperture automated variable temperature Raman microscope

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

    Tian, Y.; Reijnders, A. A.; Osterhoudt, G. B.; Valmianski, I.; Ramirez, J. G.; Urban, C.; Zhong, R.; Schneeloch, J.; Gu, G.; Henslee, I.; et al

    2016-04-05

    Raman micro-spectroscopy is well suited for studying a variety of properties and has been applied to wide- ranging areas. Combined with tuneable temperature, Raman spectra can offer even more insights into the properties of materials. However, previous designs of variable temperature Raman microscopes have made it extremely challenging to measure samples with low signal levels due to thermal and positional instability as well as low collection efficiencies. Thus, contemporary Raman microscope has found limited applicability to probing the subtle physics involved in phase transitions and hysteresis. This paper describes a new design of a closed-cycle, Raman microscope with full polarizationmore » rotation. High collection efficiency, thermal and mechanical stability are ensured by both deliberate optical, cryogenic, and mechanical design. Measurements on two samples, Bi2Se3 and V2O3, which are known as challenging due to low thermal conductivities, low signal levels and/or hysteretic effects, are measured with previously undemonstrated temperature resolution.« less

  19. Error and uncertainty in Raman thermal conductivity measurements

    SciTech Connect (OSTI)

    Thomas Edwin Beechem; Yates, Luke; Graham, Samuel

    2015-04-22

    We investigated error and uncertainty in Raman thermal conductivity measurements via finite element based numerical simulation of two geometries often employed -- Joule-heating of a wire and laser-heating of a suspended wafer. Using this methodology, the accuracy and precision of the Raman-derived thermal conductivity are shown to depend on (1) assumptions within the analytical model used in the deduction of thermal conductivity, (2) uncertainty in the quantification of heat flux and temperature, and (3) the evolution of thermomechanical stress during testing. Apart from the influence of stress, errors of 5% coupled with uncertainties of ±15% are achievable for most materials under conditions typical of Raman thermometry experiments. Error can increase to >20%, however, for materials having highly temperature dependent thermal conductivities or, in some materials, when thermomechanical stress develops concurrent with the heating. A dimensionless parameter -- termed the Raman stress factor -- is derived to identify when stress effects will induce large levels of error. Together, the results compare the utility of Raman based conductivity measurements relative to more established techniques while at the same time identifying situations where its use is most efficacious.

  20. Raman Spectroscopy of Carbon Dust Samples from NSTX

    SciTech Connect (OSTI)

    Y. Raitses, C.H. Skinner, F. Jiang and T.S. Duffy

    2008-02-21

    The Raman spectrum of dust particles exposed to the NSTX plasma is different from the spectrum of unexposed particles scraped from an unused graphite tile. For the unexposed particles, the high energy G-mode peak (Raman shift ~1580 cm-1) is much stronger than the defect-induced D-mode peak (Raman shift ~ 1350 cm-1), a pattern that is consistent with Raman spectrum for commercial graphite materials. For dust particles exposed to the plasma, the ratio of G-mode to D-mode peaks is lower and becomes even less than 1. The Raman measurements indicate that the production of carbon dust particles in NSTX involves modifications of the physical and chemical structure of the original graphite material. These modifications are shown to be similar to those measured for carbon deposits from atmospheric pressure helium arc discharge with an ablating anode electrode made from a graphite tile material. We also demonstrate experimentally that heating to 2000-2700 K alone can not explain the observed structural modifications indicating that they must be due to higher temperatures needed for graphite vaporization, which is followed either by condensation or some plasma-induced processes leading to the formation of more disordered forms of carbon material than the original graphite.

  1. Enhanced Raman Scattering on In-plane Anisotropic Layered Materials

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

    Liang, Liangbo; Meunier, Vincent; Sumpter, Bobby G.; Ling, Xi; Lin, Jingjing; Zhang, Shuqing; Mao, Nannan; Zhang, Na; Tong, Lianming; Zhang, Jin

    2015-11-19

    Surface-enhanced Raman scattering (SERS) on two-dimensional (2D) layered materials has provided a unique platform to study the chemical mechanism (CM) of the enhancement due to its natural separation from electromagnetic enhancement. The CM stems from the basic charge interactions between the substrate and molecules. Despite the extensive studies of the energy alignment between 2D materials and molecules, an understanding of how the electronic properties of the substrate are explicitly involved in the charge interaction is still unclear. Lately, a new group of 2D layered materials with anisotropic structure, including orthorhombic black phosphorus (BP) and triclinic rhenium disulphide (ReS2), has attractedmore » great interest due to their unique anisotropic electrical and optical properties. Herein, we report a unique anisotropic Raman enhancement on few-layered BP and ReS2 using copper phthalocyanine (CuPc) molecules as a Raman probe, which is absent on isotropic graphene and h-BN. According to detailed Raman tensor analysis and density functional theory calculations, anisotropic charge interactions due to the anisotropic carrier mobilities of the 2D materials are responsible for the angular dependence of the Raman enhancement. Our findings not only provide new insights into the CM process in SERS, but also open up new avenues for the exploration and application of the electronic properties of anisotropic 2D layered materials.« less

  2. Enhanced Raman Scattering on In-plane Anisotropic Layered Materials

    SciTech Connect (OSTI)

    Liang, Liangbo; Meunier, Vincent; Sumpter, Bobby G.; Ling, Xi; Lin, Jingjing; Zhang, Shuqing; Mao, Nannan; Zhang, Na; Tong, Lianming; Zhang, Jin

    2015-11-19

    Surface-enhanced Raman scattering (SERS) on two-dimensional (2D) layered materials has provided a unique platform to study the chemical mechanism (CM) of the enhancement due to its natural separation from electromagnetic enhancement. The CM stems from the basic charge interactions between the substrate and molecules. Despite the extensive studies of the energy alignment between 2D materials and molecules, an understanding of how the electronic properties of the substrate are explicitly involved in the charge interaction is still unclear. Lately, a new group of 2D layered materials with anisotropic structure, including orthorhombic black phosphorus (BP) and triclinic rhenium disulphide (ReS2), has attracted great interest due to their unique anisotropic electrical and optical properties. Herein, we report a unique anisotropic Raman enhancement on few-layered BP and ReS2 using copper phthalocyanine (CuPc) molecules as a Raman probe, which is absent on isotropic graphene and h-BN. According to detailed Raman tensor analysis and density functional theory calculations, anisotropic charge interactions due to the anisotropic carrier mobilities of the 2D materials are responsible for the angular dependence of the Raman enhancement. Our findings not only provide new insights into the CM process in SERS, but also open up new avenues for the exploration and application of the electronic properties of anisotropic 2D layered materials.

  3. Control system for a vertical axis windmill

    DOE Patents [OSTI]

    Brulle, Robert V.

    1983-10-18

    A vertical axis windmill having a rotating structure is provided with a series of articulated vertical blades whose positions are controlled to maintain a constant RPM for the rotating structure, when wind speed is sufficient. A microprocessor controller is used to process information on wind speed, wind direction and RPM of the rotating structure to develop an electrical signal for establishing blade position. The preferred embodiment of the invention, when connected to a utility grid, is designed to generate 40 kilowatts of power when exposed to a 20 mile per hour wind. The control system for the windmill includes electrical blade actuators that modulate the blades of the rotating structure. Blade modulation controls the blade angle of attack, which in turn controls the RPM of the rotor. In the preferred embodiment, the microprocessor controller provides the operation logic and control functions. A wind speed sensor provides inputs to start or stop the windmill, and a wind direction sensor is used to keep the blade flip region at 90.degree. and 270.degree. to the wind. The control system is designed to maintain constant rotor RPM when wind speed is between 10 and 40 miles per hour.

  4. High vertical resolution crosswell seismic imaging

    DOE Patents [OSTI]

    Lazaratos, Spyridon K.

    1999-12-07

    A method for producing high vertical resolution seismic images from crosswell data is disclosed. In accordance with one aspect of the disclosure, a set of vertically spaced, generally horizontally extending continuous layers and associated nodes are defined within a region between two boreholes. The specific number of nodes is selected such that the value of a particular characteristic of the subterranean region at each of the nodes is one which can be determined from the seismic data. Once values are established at the nodes, values of the particular characteristic are assigned to positions between the node points of each layer based on the values at node within that layer and without regard to the values at node points within any other layer. A seismic map is produced using the node values and the assigned values therebetween. In accordance with another aspect of the disclosure, an approximate model of the region is established using direct arrival traveltime data. Thereafter, the approximate model is adjusted using reflected arrival data. In accordance with still another aspect of the disclosure, correction is provided for well deviation. An associated technique which provides improvements in ray tracing is also disclosed.

  5. Effective Higgs vertices in the generic MSSM

    SciTech Connect (OSTI)

    Crivellin, Andreas

    2011-03-01

    In this article we consider chirally enhanced corrections to Higgs vertices in the most general MSSM. We include the contributions stemming from bilinear terms, from the trilinear A terms, and from their nonholomorphic analogues, the A{sup '} terms, which couple squarks to the ''wrong'' Higgs field. We perform a consistent renormalization of the Higgs vertices beyond the decoupling limit (M{sub SUSY{yields}{infinity}}), using a purely diagrammatic approach. The cancellation of the different contributions in and beyond the decoupling limit is discussed and the possible size of decoupling effects which occur if the supersymmetry particles are not much heavier than the electroweak scale are examined. In the decoupling limit we recover the results obtained in the effective-field-theory approach. For the nonholomorphic A{sup '} terms we find the well known tan{beta} enhancement in the down sector similar to the one for terms proportional to {mu}. Because of the a priori generic flavor structure of these trilinear terms large flavor-changing neutral Higgs couplings can be induced. We also discover new tan{beta} enhanced contributions involving the usual holomorphic A terms, which were not discussed before in the literature. These corrections occur only if also flavor-diagonal nonholomorphic corrections to the Higgs couplings are present. This reflects the fact that the A terms, and also the chirality-changing self-energies, are physical quantities and cannot be absorbed into renormalization constants.

  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. Cone penetrometer fiber optic raman spectroscopy probe assembly

    DOE Patents [OSTI]

    Kyle, Kevin R.; Brown, Steven B.

    2000-01-01

    A chemically and mechanically robust optical Raman spectroscopy probe assembly that can be incorporated in a cone penetrometer (CPT) for subsurface deployment. This assembly consists of an optical Raman probe and a penetrometer compatible optical probe housing. The probe is intended for in-situ chemical analysis of chemical constituents in the surrounding environment. The probe is optically linked via fiber optics to the light source and the detection system at the surface. A built-in broadband light source provides a strobe method for direct measurement of sample optical density. A mechanically stable sapphire window is sealed directly into the side-wall of the housing using a metallic, chemically resistant, hermetic seal design. This window permits transmission of the interrogation light beam and the resultant signal. The spectroscopy probe assembly is capable of accepting Raman, Laser induced Fluorescence, reflectance, and other optical probes with collimated output for CPT deployment.

  8. UV resonance Raman analysis of trishomocubane and diamondoid dimers

    SciTech Connect (OSTI)

    Meinke, Reinhard Thomsen, Christian; Maultzsch, Janina; Richter, Robert; Merli, Andrea; Fokin, Andrey A.; Department of Organic Chemistry, Kiev Polytechnic Institute, pr. Pobedy 37, 03056 Kiev ; Koso, Tetyana V.; Schreiner, Peter R.; Rodionov, Vladimir N.

    2014-01-21

    We present resonance Raman measurements of crystalline trishomocubane and diamantane dimers containing a C=C double bond. Raman spectra were recorded with excitation energies between 2.33eV and 5.42eV. The strongest enhancement is observed for the C=C stretch vibration and a bending mode involving the two carbon atoms of the C=C bond, corresponding to the B{sub 2g} wagging mode of ethylene. This is associated with the localization of the ?-HOMO and LUMO and the elongation of the C=C bond length and a pyramidalization of the two sp{sup 2}-hybridized carbon atoms at the optical excitation. The observed Raman resonance energies of the trishomocubane and diamantane dimers are significantly lower than the HOMO-LUMO gaps of the corresponding unmodified diamondoids.

  9. 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.

  10. Nanoscale array structures suitable for surface enhanced raman scattering and methods related thereto

    DOE Patents [OSTI]

    Bond, Tiziana C.; Miles, Robin; Davidson, James C.; Liu, Gang Logan

    2014-07-22

    Methods for fabricating nanoscale array structures suitable for surface enhanced Raman scattering, structures thus obtained, and methods to characterize the nanoscale array structures suitable for surface enhanced Raman scattering. Nanoscale array structures may comprise nanotrees, nanorecesses and tapered nanopillars.

  11. Nanoscale array structures suitable for surface enhanced raman scattering and methods related thereto

    DOE Patents [OSTI]

    Bond, Tiziana C.; Miles, Robin; Davidson, James C.; Liu, Gang Logan

    2015-07-14

    Methods for fabricating nanoscale array structures suitable for surface enhanced Raman scattering, structures thus obtained, and methods to characterize the nanoscale array structures suitable for surface enhanced Raman scattering. Nanoscale array structures may comprise nanotrees, nanorecesses and tapered nanopillars.

  12. Nanoscale array structures suitable for surface enhanced raman scattering and methods related thereto

    DOE Patents [OSTI]

    Bond, Tiziana C; Miles, Robin; Davidson, James; Liu, Gang Logan

    2015-11-03

    Methods for fabricating nanoscale array structures suitable for surface enhanced Raman scattering, structures thus obtained, and methods to characterize the nanoscale array structures suitable for surface enhanced Raman scattering. Nanoscale array structures may comprise nanotrees, nanorecesses and tapered nanopillars.

  13. High-pressure X-ray diffraction, Raman, and computational studies...

    Office of Scientific and Technical Information (OSTI)

    High-pressure X-ray diffraction, Raman, and computational studies of MgCl2 up to 1 Mbar: ... Citation Details In-Document Search Title: High-pressure X-ray diffraction, Raman, and ...

  14. Pulsed laser Raman spectroscopy in the laser-heated diamond anvil...

    Office of Scientific and Technical Information (OSTI)

    Pulsed laser Raman spectroscopy in the laser-heated diamond anvil cell Citation Details In-Document Search Title: Pulsed laser Raman spectroscopy in the laser-heated diamond anvil...

  15. High-pressure X-ray diffraction, Raman, and computational studies...

    Office of Scientific and Technical Information (OSTI)

    X-ray diffraction, Raman, and computational studies of MgCl2 up to 1 Mbar: Extensive ... Citation Details In-Document Search Title: High-pressure X-ray diffraction, Raman, and ...

  16. Trace detection of analytes using portable raman systems

    SciTech Connect (OSTI)

    Alam, M. Kathleen; Hotchkiss, Peter J.; Martin, Laura E.; Jones, David Alexander

    2015-11-24

    Apparatuses and methods for in situ detection of a trace amount of an analyte are disclosed herein. In a general embodiment, the present disclosure provides a surface-enhanced Raman spectroscopy (SERS) insert including a passageway therethrough, where the passageway has a SERS surface positioned therein. The SERS surface is configured to adsorb molecules of an analyte of interest. A concentrated sample is caused to flow over the SERS surface. The SERS insert is then provided to a portable Raman spectroscopy system, where it is analyzed for the analyte of interest.

  17. Temperature dependent Raman scattering in YCrO{sub 3}

    SciTech Connect (OSTI)

    Mall, A. K. Sharma, Y.; Mukherjee, S.; Garg, A.; Gupta, R.

    2014-04-24

    High quality polycrystalline YCrO{sub 3} samples were synthesized using solid-state-reaction method. The samples were subsequently characterized using X-ray diffraction and magnetometry. Further, temperature dependent Raman spectroscopy over a spectral range from 100 to 800 cm{sup −1} was used to examine the variation of phonons as a function of temperature from 90 to 300 K. In the low temperature ferroelectric phase of YCrO{sub 3}, the observed phonon spectra showed softening of some Raman modes below the magnetic ordering temperature (T{sub N} ∼ 142K), suggesting a coupling between the spin and phonon degrees of freedom.

  18. Resonance electronic Raman scattering in rare earth crystals

    SciTech Connect (OSTI)

    Williams, G.M.

    1988-11-10

    The intensities of Raman scattering transitions between electronic energy levels of trivalent rare earth ions doped into transparent crystals were measured and compared to theory. A particle emphasis was placed on the examination of the effect of intermediate state resonances on the Raman scattering intensities. Two specific systems were studied: Ce/sup 3 +/(4f/sup 1/) in single crystals of LuPO/sub 4/ and Er/sup 3 +/(4f/sup 11/) in single crystals of ErPO/sub 4/. 134 refs., 92 figs., 33 tabs.

  19. Ring cavity for a Raman capillary waveguide amplifir

    DOE Patents [OSTI]

    Kurnit, N.A.

    1981-01-27

    A regenerative ring amplifier and regenerative ring oscillator are described which function to feed back a portion of the Stokes signal to complete the ring cavity. The ring cavity configuration allows the CO/sub 2/ laser pump signal and Stokes signal to copropagate through the Raman capillary waveguide amplifier. A Raman capillary waveguide amplifier is also provided in the return leg of the ring cavity to increase gain without increasing the round trip time. Additionally, the ring cavity can be designed such that the amplified Stokes signal is synchronous with the mode-locked spikes of the incoming CO/sub 2/ laser pump signal.

  20. Ring cavity for a Raman capillary waveguide amplifier

    DOE Patents [OSTI]

    Kurnit, N.A.

    1983-07-19

    Disclosed is a regenerative ring amplifier and regenerative ring oscillator which function to feed back a portion of the Stokes signal to complete the ring cavity. The ring cavity configuration allows the CO[sub 2] laser pump signal and Stokes signal to copropagate through the Raman capillary waveguide amplifier. A Raman capillary waveguide amplifier is also provided in the return leg of the ring cavity to increase gain without increasing the round trip time. Additionally, the ring cavity can be designed such that the amplifier Stokes signal is synchronous with the mode-locked spikes of the incoming CO[sub 2] laser pump signal. 6 figs.

  1. Ring cavity for a raman capillary waveguide amplifier

    DOE Patents [OSTI]

    Kurnit, Norman A.

    1983-07-19

    A regenerative ring amplifier and regenerative ring oscillator which function to feed back a portion of the Stokes signal to complete the ring cavity. The ring cavity configuration allows the CO.sub.2 laser pump signal and Stokes signal to copropagate through the Raman capillary waveguide amplifier. A Raman capillary waveguide amplifier is also provided in the return leg of the ring cavity to increase gain without increasing the round trip time. Additionally, the ring cavity can be designed such that the amplifier Stokes signal is synchronous with the mode-locked spikes of the incoming CO.sub.2 laser pump signal.

  2. Ring cavity for a Raman capillary waveguide amplifier

    DOE Patents [OSTI]

    Kurnit, N.A.

    1981-01-27

    A regenerative ring amplifier and regenerative ring oscillator are described which function to feed back a portion of the Stokes signal to complete the ring cavity. The ring cavity configuration allows the CO/sub 2/ laser pump signal and Stokes signal to copropagate through the Raman capillary waveguide amplifier. A Raman capillary waveguide amplifier is also provided in the return leg of the ring cavity to increase gain without increasing the round trip time. Additionally, the ring cavity can be designed such that the amplified Stokes signal is synchronous with the mode-locked spikes of the incoming CO/sub 2/ laser pump signal.

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

    SciTech Connect (OSTI)

    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, when 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.

  4. 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.}

  5. 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.

  6. Vertical-Axis Wind Turbine Mesh Generator

    SciTech Connect (OSTI)

    2014-01-24

    VAWTGen is a mesh generator for creating a finite element beam mesh of arbitrary vertical-axis wind turbines (VAWT). The software accepts input files specifying tower and blade structural and aerodynamic descriptions and constructs a VAWT using a minimal set of inputs. VAWTs with an arbitrary number of blades can be constructed with or without a central tower. Strut connections between the tower and blades can be specified in an arbitrary manner. The software also facilitates specifying arbitrary joints between structural components and concentrated structural tenns (mass and stiffness). The output files which describe the VAWT configuration are intended to be used with the Offshore Wind ENergy Simulation (OWENS) Toolkit software for structural dynamics analysis of VAWTs. Furthermore, VAWTGen is useful for visualizing output from the OWENS analysis software.

  7. Vertical-Axis Wind Turbine Mesh Generator

    Energy Science and Technology Software Center (OSTI)

    2014-01-24

    VAWTGen is a mesh generator for creating a finite element beam mesh of arbitrary vertical-axis wind turbines (VAWT). The software accepts input files specifying tower and blade structural and aerodynamic descriptions and constructs a VAWT using a minimal set of inputs. VAWTs with an arbitrary number of blades can be constructed with or without a central tower. Strut connections between the tower and blades can be specified in an arbitrary manner. The software also facilitatesmore » specifying arbitrary joints between structural components and concentrated structural tenns (mass and stiffness). The output files which describe the VAWT configuration are intended to be used with the Offshore Wind ENergy Simulation (OWENS) Toolkit software for structural dynamics analysis of VAWTs. Furthermore, VAWTGen is useful for visualizing output from the OWENS analysis software.« less

  8. How to make Raman-inactive helium visible in Raman spectra of tritium-helium gas mixtures

    SciTech Connect (OSTI)

    Schloesser, M.; Pakari, O.; Rupp, S.; Mirz, S.; Fischer, S.

    2015-03-15

    Raman spectroscopy, a powerful method for the quantitative compositional analysis of molecular gases, e.g. mixtures of hydrogen isotopologues, is not able to detect monoatomic species like helium. This deficit can be overcome by using radioluminescence emission from helium atoms induced by β-electrons from tritium decay. We present theoretical considerations and combined Raman/radioluminescence spectra. Furthermore, we discuss the linearity of the method together with validation measurements for determining the pressure dependence. Finally, we conclude how this technique can be used for samples of helium with traces of tritium, and vice versa. (authors)

  9. Excited-state Raman spectroscopy with and without actinic excitation: S{sub 1} Raman spectra of trans-azobenzene

    SciTech Connect (OSTI)

    Dobryakov, A. L.; Quick, M.; Ioffe, I. N.; Granovsky, A. A.; Ernsting, N. P.; Kovalenko, S. A.

    2014-05-14

    We show that femtosecond stimulated Raman spectroscopy can record excited-state spectra in the absence of actinic excitation, if the Raman pump is in resonance with an electronic transition. The approach is illustrated by recording S{sub 1} and S{sub 0} spectra of trans-azobenzene in n-hexane. The S{sub 1} spectra were also measured conventionally, upon nπ* (S{sub 0} → S{sub 1}) actinic excitation. The results are discussed and compared to earlier reports.

  10. 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.

  11. Assignments of the Raman modes of monoclinic erbium oxide

    SciTech Connect (OSTI)

    Yan, D.; Wu, P. Zhang, S. P.; Liang, L.; Yang, F.; Pei, Y. L.; Chen, S.

    2013-11-21

    As a heavy rare earth oxide, erbium oxide (Er{sub 2}O{sub 3}) has many attractive properties. Monoclinic Er{sub 2}O{sub 3} has useful properties not found in stable cubic Er{sub 2}O{sub 3}, such as unique optical properties and high radiation damage tolerance. In this study, cubic Er{sub 2}O{sub 3} coating and Er{sub 2}O{sub 3} coating with mixed phases were prepared. The Raman scattering spectra of these coatings were investigated by using a confocal micro-Raman spectrometer equipped with 325, 473, 514, 532, 633, and 784 nm lasers. A total of 17 first-order Raman modes of monoclinic Er{sub 2}O{sub 3} were identified and assigned. The modes at 83, 112, 152, 170, 278, 290, 409, 446, 478, 521, 603, and 622 cm{sup −1} are of A{sub g} symmetry, whereas modes at 71, 98, 333, 409, 446, and 468 cm{sup −1} are of B{sub g} symmetry. This research provides basic data necessary for the characterization of monoclinic Er{sub 2}O{sub 3} by Raman spectroscopy.

  12. Summary of recent Raman Spectroscopy testing of SRS processes

    SciTech Connect (OSTI)

    Fondeur, F. F.; Lascola, R. J.; O'Rourke, P. E.

    2016-01-01

    This report describes several scoping projects conducted at SRNL using Raman spectroscopic methods for monitoring different aspects of nuclear waste and materials processing. One project examined the suitability of a Raman telescope for in situ measurement of solid residues in waste tanks. Characteristics evaluated for this equipment included radiation resistance, ease of use, and sensitivity. A second project monitored the nitrate content in liquid filtrate from the testing of a rotary microfilter using a fiber-based insertion probe. The third project made Raman measurements of various gases, including H2 and NOx, in the headspace of a vessel while dissolving aluminum coupons in nitric acid. Measurements followed the evolution of these species in real time. Although the majority of these projects occurred in the laboratory environment, SRNL has substantial experience with implementing other optical techniques into nuclear materials processing environments. The work described in this report shows the potential of the Raman technology to provide real time measurements of species such as nitrate or hydroxide during sludge washing or evolved gases such as hydrogen or NOx during waste processing.

  13. Raman Microscopy of Lithium-Manganese-Rich Cathodes

    SciTech Connect (OSTI)

    Ruther, Rose E; Callender, Andrew F.; Zhou, Hui; Martha, Surendra; Nanda, Jagjit

    2014-01-01

    Lithium rich, manganese rich composites with general formula xLi2MnO3 (1-x)LiMO2 are promising candidates for high capacity and high voltage cathodes for lithium ion batteries. Lithium rich oxides crystallize as a nanocomposite of layered phases whose structure further evolves with electrochemical cycling. Raman spectroscopy is potentially a powerful tool to monitor the crystal chemistry and correlate phase changes with electrochemical behavior. While several groups have reported Raman spectra of lithium rich oxides, the data show considerable variability in terms of both the vibrational features observed and their interpretation. In this study Raman microscopy is used to investigate lithium-rich manganese-rich cathodes as a function of average charge and electrochemical cycling. LMR-NMC cycled at elevated temperature (60 C) has a modified crystal structure which may account for some of the observed increase in capacity. Contrary to some reports, no growth of a spinel phase is observed. However, analysis of the Raman spectra does indicate the structure of LMR-NMC deviates significantly from an ideal layered phase. The results also highlight the importance of using low laser power and large sample sizes to obtain consistent data sets.

  14. Proliferation detection using a remote resonance Raman chemical sensor

    SciTech Connect (OSTI)

    Sedlacek, A.J.; Chen, C.L.; Dougherty, D.R.

    1993-08-01

    The authors discussed the potential of the resonance Raman chemical sensor as a remote sensor that can be used for gases, liquids or solids. This spectroscopy has the fundamental advantage that it is based on optical fingerprints that are insensitive to environmental perturbations or excitation frequency. By taking advantage of resonance enhancement, the inelastic scattering cross-section can increase anywhere from 4 to 6 orders of magnitude which translates into increased sensing range or lower detection limits. It was also shown that differential cross-sections as small as 10{sup {minus}27} cm{sup 2}/sr do not preclude the use of this technique as being an important component in one`s remote-sensing arsenal. The results obtained in the early 1970s on various pollutants and the more recent work on atmospheric water cast a favorable light on the prospects for the successful development of a resonance Raman remote sensor. Currently, of the 20 CW agent-related {open_quotes}signature{close_quotes} chemicals that the authors have investigated, 18 show enhancements ranging from 3 to 6 orders of magnitude. The absolute magnitudes of the measured resonance enhanced Raman cross-sections for these 18 chemicals suggest that detection and identification of trace quantities of the {open_quotes}signature{close_quotes} chemicals, through a remote resonance Raman chemical sensor, could be achieved.

  15. Reduced soliton interaction by Raman self-frequency-shift

    SciTech Connect (OSTI)

    Hause, A.; Mitschke, F.

    2009-12-15

    We show that the interaction of adjacent fiber-optic solitons can be reduced by the Raman self-frequency shift. As the frequency slides, the interaction periodically alternates between attraction and repulsion. If this happens sufficiently rapidly, the forces largely average out. We present a simplified analytical model and compare its predictions to numerical simulations.

  16. Raman Microscopy of Lithium-Manganese-Rich Cathodes

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

    Ruther, Rose E; Callender, Andrew F.; Zhou, Hui; Martha, Surendra; Nanda, Jagjit

    2014-01-01

    Lithium rich, manganese rich composites with general formula xLi2MnO3 (1-x)LiMO2 are promising candidates for high capacity and high voltage cathodes for lithium ion batteries. Lithium rich oxides crystallize as a nanocomposite of layered phases whose structure further evolves with electrochemical cycling. Raman spectroscopy is potentially a powerful tool to monitor the crystal chemistry and correlate phase changes with electrochemical behavior. While several groups have reported Raman spectra of lithium rich oxides, the data show considerable variability in terms of both the vibrational features observed and their interpretation. In this study Raman microscopy is used to investigate lithium-rich manganese-rich cathodes asmore » a function of average charge and electrochemical cycling. LMR-NMC cycled at elevated temperature (60 C) has a modified crystal structure which may account for some of the observed increase in capacity. Contrary to some reports, no growth of a spinel phase is observed. However, analysis of the Raman spectra does indicate the structure of LMR-NMC deviates significantly from an ideal layered phase. The results also highlight the importance of using low laser power and large sample sizes to obtain consistent data sets.« less

  17. Robotic platform for traveling on vertical piping network

    DOE Patents [OSTI]

    Nance, Thomas A; Vrettos, Nick J; Krementz, Daniel; Marzolf, Athneal D

    2015-02-03

    This invention relates generally to robotic systems and is specifically designed for a robotic system that can navigate vertical pipes within a waste tank or similar environment. The robotic system allows a process for sampling, cleaning, inspecting and removing waste around vertical pipes by supplying a robotic platform that uses the vertical pipes to support and navigate the platform above waste material contained in the tank.

  18. Conventional Energy Forum & Associated Vertical Business Development: Best

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

    Practices in Indian Country | Department of Energy Conventional Energy Forum & Associated Vertical Business Development: Best Practices in Indian Country Conventional Energy Forum & Associated Vertical Business Development: Best Practices in Indian Country March 1, 2012 Las Vegas, Nevada Mandalay Bay Resort & Casino The Office of Indian Energy Tribal Leader Energy Forum on "Conventional Energy (Oil, Gas, and Coal) Forum & Associated Vertical Business Development: Best

  19. Summary of Convective Core Vertical Velocity Properties Using...

    Office of Scientific and Technical Information (OSTI)

    Title: Summary of Convective Core Vertical Velocity Properties Using ARM UHF Wind Profilers in Oklahoma Authors: Giangrande S. E. ; Collis, S. ; Straka, J. ; Protat, A. ; Williams, ...

  20. Conventional Energy (Oil, Gas, and Coal) Forum & Associated Vertical...

    Office of Environmental Management (EM)

    CONVENTIONAL ENERGY (OIL, GAS & COAL) FORUM & ASSOCIATED VERTICAL BUSINESS DEVELOPMENT ... South, Las Vegas, NV 89119 The dynamic world of conventional energy (focusing on oil, gas ...

  1. An ultimate storage ring lattice with vertical emittance generated...

    Office of Scientific and Technical Information (OSTI)

    Journal Article: An ultimate storage ring lattice with vertical emittance generated by damping wigglers Citation Details In-Document Search Title: An ultimate storage ring lattice...

  2. Vertical Electrical Sounding Configurations At Mt Princeton Hot...

    Open Energy Info (EERE)

    navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Vertical Electrical Sounding Configurations At Mt Princeton Hot Springs Geothermal Area (Zohdy, Et Al.,...

  3. Instrument Development Tethered Balloon Sounding System for Vertical...

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

    Tethered Balloon Sounding System for Vertical Radiation Profiles C. D. Whiteman J. M. Alzheimer G. A. Anderson M. R. Garnich W. J. Shaw Pacific Northwest Laboratory Richland, WA...

  4. LONG-TERM DYNAMICS OF RADIONUCLIDE VERTICAL MIGRATION IN SOILS...

    Office of Scientific and Technical Information (OSTI)

    NUCLEAR POWER PLANT EXCLUSION ZONE Citation Details In-Document Search Title: LONG-TERM DYNAMICS OF RADIONUCLIDE VERTICAL MIGRATION IN SOILS OF THE CHERNOBYL NUCLEAR POWER ...

  5. Vertical Emmittance Studies at the ATF Damping Ring (Technical...

    Office of Scientific and Technical Information (OSTI)

    Visit OSTI to utilize additional information resources in energy science and technology. A ... A primary purpose of the ATF Damping Ring is to demonstrate the small vertical emittance ...

  6. Raman spectroscopy of titanomagnetites: Calibration of the intensity of Raman peaks as a sensitive indicator for their Ti content

    SciTech Connect (OSTI)

    Zinin, Pavel; Tatsumi-Petrochilos, Lisa; Bonal, Lydie; Acosta, Tayro; Hammer, Julia; Gilder, Stuart; Fuller, Mike

    2015-10-15

    A systematic study of the Raman spectra of the titanomagnetite solid-solution series (Fe{sub 3-x}Ti{sub x}O{sub 4}) for x = {approx}0.0, 0.2, 0.4, and 0.6 has been conducted. The samples showed combinations of five previously predicted Raman peaks at {approx}190, 310, 460, 540, and 670 cm{sup -1} that correspond to vibrational modes with T{sub 2g}(1), E{sub g}, T{sub 2g}(3), T{sub 2g}(2), and A{sub 1g}, respectively. The calibration of Raman spectra for titanomagnetite with known values of Ti concentrations reveals a strong dependence of relative intensity for the T{sub 2g}(2) and T{sub 2g}(3) modes on Ti concentration. The most prominent feature is the appearance and increase in the relative intensity of a T{sub 2g}(3) peak above x = {approx}0.2. On the other hand, the Raman peak for the T{sub 2g}(2) mode gradually diminishes as Ti increases and nearly disappears at x = {approx}0.6. Combining the two relative intensities potentially provides a sensitive indicator of Ti content. The technique was applied to study titanomagnetite in grains from Hana Volcanics and melatroctolite from Rhode Island.

  7. Raman lidar measurements of water vapor and aerosols during the atmospheric radiation measurement (ARM) remote clouds sensing (RCS) intensive observation period (IOP)

    SciTech Connect (OSTI)

    Melfi, S.H.; Starr, D.O`C.; Whiteman, D.

    1996-04-01

    The first Atmospheric Radiation Measurement (ARM) remote Cloud Study (RCS) Intensive Operations Period (IOP) was held during April 1994 at the Southern Great Plains (SGP) site. This experiment was conducted to evaluate and calibrate state-of-the-art, ground based remote sensing instruments and to use the data acquired by these instruments to validate retrieval algorithms developed under the ARM program.

  8. Engineering design of vertical test stand cryostat

    SciTech Connect (OSTI)

    Suhane, S.K.; Sharma, N.K.; Raghavendra, S.; Joshi, S.C.; Das, S.; Kush, P.K.; Sahni, V.C.; Gupta, P.D.; Sylvester, C.; Rabehl, R.; Ozelis, J.; /Fermilab

    2011-03-01

    Under Indian Institutions and Fermilab collaboration, Raja Ramanna Centre for Advanced Technology and Fermi National Accelerator Laboratory are jointly developing 2K Vertical Test Stand (VTS) cryostats for testing SCRF cavities at 2K. The VTS cryostat has been designed for a large testing aperture of 86.36 cm for testing of 325 MHz Spoke resonators, 650 MHz and 1.3 GHz multi-cell SCRF cavities for Fermilab's Project-X. Units will be installed at Fermilab and RRCAT and used to test cavities for Project-X. A VTS cryostat comprises of liquid helium (LHe) vessel with internal magnetic shield, top insert plate equipped with cavity support stand and radiation shield, liquid nitrogen (LN{sub 2}) shield and vacuum vessel with external magnetic shield. The engineering design and analysis of VTS cryostat has been carried out using ASME B&PV Code and Finite Element Analysis. Design of internal and external magnetic shields was performed to limit the magnetic field inside LHe vessel at the cavity surface <1 {micro}T. Thermal analysis for LN{sub 2} shield has been performed to check the effectiveness of LN{sub 2} cooling and for compliance with ASME piping code allowable stresses.

  9. Free convective condensation in a vertical enclosure

    SciTech Connect (OSTI)

    Fox, R.J.; Peterson, P.F.; Corradini, M.L.; Pernsteiner, A.P.

    1995-09-01

    Free convective condensation in a vertical enclosure was studied numerically and the results were compared with experiments. In both the numerical and experimental investigations, mist formation was observed to occur near the cooling wall, with significant droplet concentrations in the bulk. Large recirculation cells near the end of the condensing section were generated as the heavy noncondensing gas collecting near the cooling wall was accelerated downward. Near the top of the enclosure the recirculation cells became weaker and smaller than those below, ultimately disappearing near the top of the condenser. In the experiment the mist density was seen to be highest near the wall and at the bottom of the condensing section, whereas the numerical model predicted a much more uniform distribution. The model used to describe the formation of mist was based on a Modified Critical Saturation Model (MCSM), which allows mist to be generated once the vapor pressure exceeds a critical value. Equilibrium, nonequilibrium, and MCSM calculations were preformed, showing the experimental results to lie somewhere in between the equilibrium and nonequilibrium predictions of the numerical model. A single adjustable constant (indicating the degree to which equilibrium is achieved) is used in the model in order to match the experimental results.

  10. Vertical barriers with increased sorption capacities

    SciTech Connect (OSTI)

    Bradl, H.B.

    1997-12-31

    Vertical barriers are commonly used for the containment of contaminated areas. Due to the very small permeability of the barrier material which is usually in the order of magnitude of 10-10 m/s or less the advective contaminant transport can be more or less neglected. Nevertheless, there will always be a diffusive contaminant transport through the barrier which is caused by the concentration gradient. Investigations have been made to increase the sorption capacity of the barrier material by adding substances such as organoclays, zeolites, inorganic oxides and fly ashes. The contaminants taken into account where heavy metals (Pb) and for organic contaminants Toluole and Phenantrene. The paper presents results of model calculations and experiments. As a result, barrier materials can be designed {open_quotes}tailor-made{close_quotes} depending on the individual contaminant range of each site (e.g. landfills, gasworks etc.). The parameters relevant for construction such as rheological properties, compressive strength and permeability are not affected by the addition of the sorbents.

  11. ARM - VAP Product - 10rlproftemp1news

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

    rlproftemp1news Documentation Data Management Facility Plots (Quick Looks) Citation DOI: 10.5439/1095307 [ What is this? ] Generate Citation 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 VAP Output : 10RLPROFTEMP1NEWS Temperature Profiles from Raman Lidar at 10-min averaging interval Active Dates 2009.01.01 - 2015.09.29 Originating VAP Process Raman LIDAR Vertical Profiles : RLPROF Measurements The measurements

  12. ARM - VAP Product - 10srlprofmr1turn

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

    srlprofmr1turn Documentation Data Management Facility Plots (Quick Looks) Citation DOI: 10.5439/1027724 [ What is this? ] Generate Citation 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 VAP Output : 10SRLPROFMR1TURN Raman LIDAR (RL): 10-sec water vapor mixing ratio andrelative humidity profiles , along with PWV Active Dates 2004.10.01 - 2015.09.23 Originating VAP Process Raman LIDAR Vertical Profiles : RLPROF

  13. ARM - VAP Product - 1rlprofext1ferr

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

    rlprofext1ferr Documentation Data Management Facility Plots (Quick Looks) Citation DOI: 10.5439/1027733 [ What is this? ] Generate Citation 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 VAP Output : 1RLPROFEXT1FERR 1-minute Raman Lidar: aerosol extinction profiles and aerosol optical thickness, from first Ferrare algorithm Active Dates 2004.10.01 - 2015.09.23 Originating VAP Process Raman LIDAR Vertical Profiles :

  14. ARM - VAP Product - 2rlprofdep1turn

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

    Productsrlprof2rlprofdep1turn Documentation Data Management Facility Plots (Quick Looks) Citation DOI: 10.5439/1027735 [ What is this? ] Generate Citation 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 VAP Output : 2RLPROFDEP1TURN 2-minute Raman Lidar: aerosol depolarization profiles and single layer cloud optical depths Active Dates 2004.10.01 - 2015.09.25 Originating VAP Process Raman LIDAR Vertical Profiles :

  15. ARM - VAP Product - 60rlproftemp1news

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

    Productsrlprof60rlproftemp1news Documentation Data Management Facility Plots (Quick Looks) Citation DOI: 10.5439/1095309 [ What is this? ] Generate Citation 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 VAP Output : 60RLPROFTEMP1NEWS Temperature Profiles from Raman Lidar at 60-min averaging interval Active Dates 2009.01.01 - 2015.10.01 Originating VAP Process Raman LIDAR Vertical Profiles : RLPROF Measurements The

  16. Aerosol Plume Detection Algorithm Based on Image Segmentation of Scanning Atmospheric Lidar Data

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

    Weekley, R. Andrew; Goodrich, R. Kent; Cornman, Larry B.

    2016-04-06

    An image-processing algorithm has been developed to identify aerosol plumes in scanning lidar backscatter data. The images in this case consist of lidar data in a polar coordinate system. Each full lidar scan is taken as a fixed image in time, and sequences of such scans are considered functions of time. The data are analyzed in both the original backscatter polar coordinate system and a lagged coordinate system. The lagged coordinate system is a scatterplot of two datasets, such as subregions taken from the same lidar scan (spatial delay), or two sequential scans in time (time delay). The lagged coordinatemore » system processing allows for finding and classifying clusters of data. The classification step is important in determining which clusters are valid aerosol plumes and which are from artifacts such as noise, hard targets, or background fields. These cluster classification techniques have skill since both local and global properties are used. Furthermore, more information is available since both the original data and the lag data are used. Performance statistics are presented for a limited set of data processed by the algorithm, where results from the algorithm were compared to subjective truth data identified by a human.« less

  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. 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%.

  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. 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.

  2. Reduced graphene oxide and vertically aligned carbon nanotubes superhydrophilic films for supercapacitors devices

    SciTech Connect (OSTI)

    Zanin, H.; Saito, E.; Ceragioli, H.J.; Baranauskas, V.; Corat, E.J.

    2014-01-01

    Graphical abstract: - Highlights: Graphene nanosheets were produced onto wire rods. RGO and VACNT-O were evaluated and compared as supercapacitor electrode. RGO and VACNT-O have structural and electrochemical properties quite similars. The materials present good specific capacitance, energy storage and power delivery. - Abstract: Reduced graphene oxide (RGO) and vertically aligned carbon nanotubes (VACNT) superhydrophilic films were prepared by chemical vapor deposition techniques for electrical energy storage investigations. These electrodes were characterized in terms of their material and electrochemical properties by scanning electron microscopy (SEM), surface wettability, Fourier transform infrared spectroscopy (FTIR), energy dispersive and Raman spectroscopies, cyclic voltammetry (CV) and galvanostatic chargedischarge. We observed several physical structural and electrochemical similarities between these carbon-based materials with particular attention to very good specific capacitance, ultra-high energy storage and fast power delivery. Our results showed that the main difference between specific capacitance values is attributed to pseudocapacitive contribution and high density of multiwall nanotubes tips. In this work we have tested a supercapacitor device using the VACNT electrodes.

  3. Vertically aligned crystalline silicon nanowires with controlled diameters for energy conversion applications: Experimental and theoretical insights

    SciTech Connect (OSTI)

    Razek, Sara Abdel; Swillam, Mohamed A.; Allam, Nageh K.

    2014-05-21

    Vertically orientated single crystalline silicon nanowire (SiNW) arrays with controlled diameters are fabricated via a metal-assisted chemical etching method. The diameter of the fabricated nanowires is controlled by simply varying the etching time in HF/H{sub 2}O{sub 2} electrolytes. The fabricated SiNWs have diameters ranging from 117 to 650?nm and lengths from 8 to 18??m. The optical measurements showed a significant difference in the reflectance/absorption of the SiNWs with different diameters, where the reflectance increases with increasing the diameter of the SiNWs. The SiNWs showed significant photoluminescence (PL) emission spectra with peaks lying between 380 and 670?nm. The PL intensity increases as the diameter increases and shows red shift for peaks at ?670?nm. The increase or decrease of reflectivity is coincident with PL intensity at wavelength ?660?nm. The x-ray diffraction patterns confirm the high crystallinity of the fabricated SiNWs. In addition, the Raman spectra showed a shift in the first order transverse band toward lower frequencies compared to that usually seen for c-Si. Finite difference time domain simulations have been performed to confirm the effect of change of diameter on the optical properties of the nanowires. The simulation results showed good agreement with the experimental results for the SiNWs of different diameters.

  4. 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.

  5. Steerable vertical to horizontal energy transducer for mobile robots

    DOE Patents [OSTI]

    Spletzer, Barry L.; Fischer, Gary J.; Feddema, John T.

    2001-01-01

    The present invention provides a steerable vertical to horizontal energy transducer for mobile robots that less complex and requires less power than two degree of freedom tilt mechanisms. The present invention comprises an end effector that, when mounted with a hopping actuator, translates along axis (typically vertical) actuation into combined vertical and horizontal motion. The end effector, or foot, mounts with an end of the actuator that moves toward the support surface (typically a floor or the earth). The foot is shaped so that the first contact with the support surface is off the axis of the actuator. Off-axis contact with the support surface generates an on-axis force (typically resulting in vertical motion) and a moment orthogonal to the axis. The moment initiates a horizontal tumbling motion, and tilts the actuator so that its axis is oriented with a horizontal component and continued actuation generates both vertical and horizontal force.

  6. Theoretic base of Edge Local Mode triggering by vertical displacements

    SciTech Connect (OSTI)

    Wang, Z. T.; He, Z. X.; Wang, Z. H.; Wu, N.; Tang, C. J.

    2015-05-15

    Vertical instability is studied with R-dependent displacement. For Solovev's configuration, the stability boundary of the vertical instability is calculated. The pressure gradient is a destabilizing factor which is contrary to Rebhan's result. Equilibrium parallel current density, j{sub //}, at plasma boundary is a drive of the vertical instability similar to Peeling-ballooning modes; however, the vertical instability cannot be stabilized by the magnetic shear which tends towards infinity near the separatrix. The induced current observed in the Edge Local Mode (ELM) triggering experiment by vertical modulation is derived. The theory provides some theoretic explanation for the mitigation of type-I ELMS on ASDEX Upgrade. The principle could be also used for ITER.

  7. A path towards uncertainty assignment in an operational cloud-phase algorithm from ARM vertically pointing active sensors

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

    Riihimaki, Laura D.; Comstock, Jennifer M.; Anderson, Kevin K.; Holmes, Aimee; Luke, Edward

    2016-06-10

    Knowledge of cloud phase (liquid, ice, mixed, etc.) is necessary to describe the radiative impact of clouds and their lifetimes, but is a property that is difficult to simulate correctly in climate models. One step towards improving those simulations is to make observations of cloud phase with sufficient accuracy to help constrain model representations of cloud processes. In this study, we outline a methodology using a basic Bayesian classifier to estimate the probabilities of cloud-phase class from Atmospheric Radiation Measurement (ARM) vertically pointing active remote sensors. The advantage of this method over previous ones is that it provides uncertainty informationmore » on the phase classification. We also test the value of including higher moments of the cloud radar Doppler spectrum than are traditionally used operationally. Using training data of known phase from the Mixed-Phase Arctic Cloud Experiment (M-PACE) field campaign, we demonstrate a proof of concept for how the method can be used to train an algorithm that identifies ice, liquid, mixed phase, and snow. Over 95 % of data are identified correctly for pure ice and liquid cases used in this study. Mixed-phase and snow cases are more problematic to identify correctly. When lidar data are not available, including additional information from the Doppler spectrum provides substantial improvement to the algorithm. This is a first step towards an operational algorithm and can be expanded to include additional categories such as drizzle with additional training data.« less

  8. Stochastic Liouville equations for femtosecond stimulated Raman spectroscopy

    SciTech Connect (OSTI)

    Agarwalla, Bijay Kumar; Ando, Hideo; Dorfman, Konstantin E.; Mukamel, Shaul

    2015-01-14

    Electron and vibrational dynamics of molecules are commonly studied by subjecting them to two interactions with a fast actinic pulse that prepares them in a nonstationary state and after a variable delay period T, probing them with a Raman process induced by a combination of a broadband and a narrowband pulse. This technique, known as femtosecond stimulated Raman spectroscopy (FSRS), can effectively probe time resolved vibrational resonances. We show how FSRS signals can be modeled and interpreted using the stochastic Liouville equations (SLE), originally developed for NMR lineshapes. The SLE provide a convenient simulation protocol that can describe complex dynamics caused by coupling to collective bath coordinates at much lower cost than a full dynamical simulation. The origin of the dispersive features that appear when there is no separation of timescales between vibrational variations and the dephasing time is clarified.

  9. Ultrafast stimulated Raman parallel adiabatic passage by shaped pulses

    SciTech Connect (OSTI)

    Dridi, G.; Guerin, S.; Hakobyan, V.; Jauslin, H. R.; Eleuch, H.

    2009-10-15

    We present a general and versatile technique of population transfer based on parallel adiabatic passage by femtosecond shaped pulses. Their amplitude and phase are specifically designed to optimize the adiabatic passage corresponding to parallel eigenvalues at all times. We show that this technique allows the robust adiabatic population transfer in a Raman system with the total pulse area as low as 3{pi}, corresponding to a fluence of one order of magnitude below the conventional stimulated Raman adiabatic passage process. This process of short duration, typically picosecond and subpicosecond, is easily implementable with the modern pulse shaper technology and opens the possibility of ultrafast robust population transfer with interesting applications in quantum information processing.

  10. Surface-Enhanced Raman Optical Data Storage system

    DOE Patents [OSTI]

    Vo-Dinh, T.

    1991-03-12

    A method and apparatus for a Surface-Enhanced Raman Optical Data Storage (SERODS) System are disclosed. A medium which exhibits the Surface Enhanced Raman Scattering (SERS) phenomenon has data written onto its surface of microenvironment by means of a write-on procedure which disturbs the surface or microenvironment of the medium and results in the medium having a changed SERS emission when excited. The write-on procedure is controlled by a signal that corresponds to the data to be stored so that the disturbed regions on the storage device (e.g., disk) represent the data. After the data is written onto the storage device it is read by exciting the surface of the storage device with an appropriate radiation source and detecting changes in the SERS emission to produce a detection signal. The data is then reproduced from the detection signal. 5 figures.

  11. Surface-enhanced raman optical data storage system

    DOE Patents [OSTI]

    Vo-Dinh, Tuan

    1991-01-01

    A method and apparatus for a Surface-Enhanced Raman Optical Data Storage (SERODS) System is disclosed. A medium which exhibits the Surface Enhanced Raman Scattering (SERS) phenomenon has data written onto its surface of microenvironment by means of a write-on procedure which disturbs the surface or microenvironment of the medium and results in the medium having a changed SERS emission when excited. The write-on procedure is controlled by a signal that corresponds to the data to be stored so that the disturbed regions on the storage device (e.g., disk) represent the data. After the data is written onto the storage device it is read by exciting the surface of the storage device with an appropriate radiation source and detecting changes in the SERS emission to produce a detection signal. The data is then reproduced from the detection signal.

  12. The application of Raman laser in gravity measurement and metrology

    SciTech Connect (OSTI)

    Ru, Ning; Zhang, Li; Wang, Yu; Fan, Shangchun

    2014-05-27

    Atom Interferometry is proved to be a potential method for measuring the acceleration of atoms due to Gravity, we are now building a feasible system of cold atom gravimeter, it is based on the atom interferometry technology by coherently manipulating the cold atoms in a fountain (with a height of 1m) with specific Raman lasers, the cold atom wave packet is splitted, combined, and then re-splitted in the process. Then the atomic wave packet will acquire different phase because of the different evolution path. The precise acceleration can be deduced through the precision measurement of atomic interference fringes phase, and this will be a high precision standard of acceleration. At present, the preparation of Raman laser and the precise control of the laser Frequency have been finished, and they have been proved to meet the requirements of the experiment.

  13. 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.; Henson, Tammy D.; Krumel, Leslie J.; Hargis, Jr., Philip J.

    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.

  14. Direct transfer and Raman characterization of twisted graphene bilayer

    SciTech Connect (OSTI)

    Othmen, R.; Ajlani, H.; Oueslati, M.; Cavanna, A.; Madouri, A.

    2015-03-09

    Twisted bilayer graphene (tBLG) is constituted of a two-graphene layer with a mismatch angle θ between the two hexagonal structures. It has recently attracted much attention—thanks to its diverse electronic and optical properties. Here, we study the tBLG fabricated by the direct transfer of graphene monolayer prepared by chemical vapor deposition (CVD) onto another CVD graphene layer remaining attached to the copper foil. We show that high quality and homogeneous tBLG can be obtained by the direct transfer which prevents interface contamination. In this situation, the top graphene layer plays a supporting mechanical role to the bottom graphene layer as confirmed by optical microscopy, scanning electron microscopy, and Raman spectroscopy measurements. The effect of annealing tBLG was also investigated using micro-Raman spectroscopy. The Raman spectra exhibit a splitting of the G peak as well as a change in the 2D band shape indicating a possible decoupling of the two monolayers. We attribute these changes to the different interactions of the top and bottom layers with the substrate.

  15. Achieving molecular selectivity in imaging using multiphoton Raman spectroscopy techniques

    SciTech Connect (OSTI)

    Holtom, Gary R. ); Thrall, Brian D. ); Chin, Beek Yoke ); Wiley, H Steven ); Colson, Steven D. )

    2000-12-01

    In the case of most imaging methods, contrast is generated either by physical properties of the sample (Differential Image Contrast, Phase Contrast), or by fluorescent labels that are localized to a particular protein or organelle. Standard Raman and infrared methods for obtaining images are based upon the intrinsic vibrational properties of molecules, and thus obviate the need for attached flurophores. Unfortunately, they have significant limitations for live-cell imaging. However, an active Raman method, called Coherent Anti-Stokes Raman Scattering (CARS), is well suited for microscopy, and provides a new means for imaging specific molecules. Vibrational imaging techniques, such as CARS, avoid problems associated with photobleaching and photo-induced toxicity often associated with the use of fluorescent labels with live cells. Because the laser configuration needed to implement CARS technology is similar to that used in other multiphoton microscopy methods, such as two -photon fluorescence and harmonic generation, it is possible to combine imaging modalities, thus generating simultaneous CARS and fluorescence images. A particularly powerful aspect of CARS microscopy is its ability to selectively image deuterated compounds, thus allowing the visualization of molecules, such as lipids, that are chemically indistinguishable from the native species.

  16. Raman fiber optic probe assembly for use in hostile environments

    DOE Patents [OSTI]

    Schmucker, John E.; Falk, Jon C.; Archer, William B.; Blasi, Raymond J.

    2000-01-01

    This invention provides a device for Raman spectroscopic measurement of composition and concentrations in a hostile environment by the use of a first fiber optic as a means of directing high intensity monochromatic light from a laser to the hostile environment and a second fiber optic to receive the lower intensity scattered light for transmittal to a monochromator for analysis. To avoid damage to the fiber optics, they are protected from the hostile environment. A preferred embodiment of the Raman fiber optic probe is able to obtain Raman spectra of corrosive gases and solutions at temperatures up to 600.degree. F. and pressures up to 2000 psi. The incident exciting fiber optic cable makes an angle of substantially 90.degree. with the collecting fiber optic cable. This 90.degree. geometry minimizes the Rayleigh scattering signal picked up by the collecting fiber, because the intensity of Rayleigh scattering is lowest in the direction perpendicular to the beam path of the exciting light and therefore a 90.degree. scattering geometry optimizes the signal to noise ratio.

  17. 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.

  18. 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.

  19. Enhanced Raman Scattering from Aromatic Dithiols Electrosprayed into Plasmonic Nanojunctions

    SciTech Connect (OSTI)

    El-Khoury, Patrick Z.; Johnson, Grant E.; Novikova, Irina V.; Gong, Yu; Joly, Alan G.; Evans, James E.; Zamkov, Mikhail; Laskin, Julia; Hess, Wayne P.

    2015-12-01

    We describe surface enhanced Raman spectroscopy (SERS) experiments in which molecular coverage is systematically varied from 3.8 x 105 to 3.8 x 102 to 0.38 molecules/μm2 using electrospray deposition of ethanolic 4,4’-dimercaptostilbene (DMS) solutions. The plasmonic SERS substrate used herein consists of a well-characterized 2-dimensional (2D) array of silver nanospheres [see El-Khoury et al., J. Chem. Phys., 2014, 141, 214308], previously shown to feature uniform topography and plasmonic response, as well as intense SERS activity. When compared to their ensemble averaged analogues, the spatially and temporally averaged spectra of a single molecule exhibit several unique features including: (i) distinct relative intensities of the observable Raman-active vibrational states, (ii) more pronounced SERS backgrounds, and (iii) broader Raman lines indicative of faster vibrational dephasing. The first observation may be understood on the basis of an intuitive physical picture in which removal of averaging over multiple molecules exposes the tensorial nature of Raman scattering. When an oriented single molecule gives rise to the recorded SERS spectra, the relative orientation of the molecule with respect to vector components of the local electric field determines the relative intensities of the observable vibrational states. Using a single molecule SERS framework described herein, we derive a unique molecular orientation in which a single DMS molecule is isolated at a nanojunction formed between two silver nanospheres in the 2D array. The DMS molecule is found lying nearly flat with respect to the metal surface. The derived orientation of a single molecule at a plasmonic nanojunction is consistent with observations (ii) and (iii). In particular, a careful inspection of the temporal spectral variations along the recorded single molecule SERS time sequences reveals that the time-averaged SERS backgrounds arise from individual molecular events, marked by broadened SERS

  20. Sidewall containment of liquid metal with vertical alternating magnetic fields

    DOE Patents [OSTI]

    Lari, R.J.; Praeg, W.F.; Turner, L.R.; Battles, J.E.; Hull, J.R.; Rote, D.M.

    1990-12-04

    An apparatus is disclosed for containing molten metal using a magnet producing vertical alternating magnetic field positioned adjacent the area in which the molten metal is to be confined. This invention can be adapted particularly to the casting of metal between counter-rotating rollers with the vertical alternating magnetic field used to confine the molten metal at the edges of the rollers. Alternately, the vertical alternating magnetic field can be used as a flow regulator in casting molten metal from an opening in a channel. 9 figs.

  1. Sidewall containment of liquid metal with vertical alternating magnetic fields

    DOE Patents [OSTI]

    Lari, Robert J.; Praeg, Walter F.; Turner, Larry R.; Battles, James E.; Hull, John R.; Rote, Donald M.

    1990-01-01

    An apparatus for containing molten metal using a magnet producing vertical alternating magnetic field positioned adjacent the area in which the molten metal is to be confined. This invention can be adapted particularly to the casting of metal between counter-rotating rollers with the vertical alternating magnetic field used to confine the molten metal at the edges of the rollers. Alternately, the vertical alternating magnetic field can be used as a flow regulator in casting molten metal from an opening in a channel.

  2. Sidewall containment of liquid metal with vertical alternating magnetic fields

    DOE Patents [OSTI]

    Lari, R.J.; Praeg, W.F.; Turner, L.R.; Battles, J.E.; Hull, J.R.; Rote, D.M.

    1988-06-17

    An apparatus for containing molten metal using a magnet producing vertical alternating magnetic field positioned adjacent to the area in which the molten metal is to be confined. This invention can be adapted particularly to the casting of metal between counter-rotating rollers with the vertical alternating magnetic field used to confine the molten metal at the edges of the rollers. Alternately, the vertical alternating magnetic field can be used as a flow regulator in casting molten metal from an opening in a channel. 8 figs.

  3. Plasmon enhanced Raman scattering effect for an atom near a carbon nanotube

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

    Bondarev, I. V.

    2015-01-01

    Quantum electrodynamics theory of the resonance Raman scattering is developed for an atom in a close proximity to a carbon nanotube. The theory predicts a dramatic enhancement of the Raman intensity in the strong atomic coupling regime to nanotube plasmon near-fields. This resonance scattering is a manifestation of the general electromagnetic surface enhanced Raman scattering effect, and can be used in designing efficient nanotube based optical sensing substrates for single atom detection, precision spontaneous emission control, and manipulation.

  4. Study Compares Floating-Platform Options for Offshore Vertical...

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

    ... deep-water vertical-axis wind turbines (VAWTs). This analysis uses a 5 MW VAWT topside design envelope created by Sandia to compare floating platform options for each turbine in ...

  5. Raman vibrational spectra of bulk to monolayer Re S 2 with lower...

    Office of Scientific and Technical Information (OSTI)

    Title: Raman vibrational spectra of bulk to monolayer Re S 2 with lower symmetry Authors: Feng, Yanqing ; Zhou, Wei ; Wang, Yaojia ; Zhou, Jian ; Liu, Erfu ; Fu, Yajun ; Ni, ...

  6. Vertical microphysical profiles of convective clouds as a tool for

    Office of Scientific and Technical Information (OSTI)

    obtaining aerosol cloud-mediated climate forcings (Technical Report) | SciTech Connect Vertical microphysical profiles of convective clouds as a tool for obtaining aerosol cloud-mediated climate forcings Citation Details In-Document Search Title: Vertical microphysical profiles of convective clouds as a tool for obtaining aerosol cloud-mediated climate forcings Quantifying the aerosol/cloud-mediated radiative effect at a global scale requires simultaneous satellite retrievals of cloud

  7. Evaluation of cloudless-sky periods detected by shortwave and longwave algorithms using lidar measurements

    SciTech Connect (OSTI)

    Dupont, Jean-Charles; Haeffelin, M.; Long, Charles N.

    2008-05-30

    Identifying cloud-free period is an important task as they are common references in cloud and aerosol radiative forcing studies. Their identification requires precise methods to distinguish condensed water from other aerosols (eg mineral or moist hydrophyle aerosols). In this study we combine analyses of wide field of view shortwave and longwave irradiances and lidar backscatter measurements to explore situations that are considered neither completely clear nor cloudy. We find that cloud-free periods detected by analysis of the broadband measurements are also identified as cloud free by the lidar in more than 60% of situations. Residual occurrences are composed of 90% high-altitude cirrus clouds, partitioned equally between subvisible and semi-transparent optical thickness classes.

  8. 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.

  9. 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.

  10. Feasibility of tropospheric water vapor profiling using infrared heterodyne differential absorption lidar

    SciTech Connect (OSTI)

    Grund, C.J.; Hardesty, R.M.; Rye, B.J.

    1996-04-01

    The development and verification of realistic climate model parameterizations for clouds and net radiation balance and the correction of other site sensor observations for interferences due to the presence of water vapor are critically dependent on water vapor profile measurements. In this study, we develop system performance models and examine the potential of infrared differential absoroption lidar (DIAL) to determine the concentration of water vapor.

  11. DOE/SC-ARM/TR-098 Micropulse Lidar Cloud Mask Value-Added Product Technical Report

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

    8 Micropulse Lidar Cloud Mask Value-Added Product Technical Report C Sivaraman J Comstock July 2011 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

  12. Remote Sensing of Complex Flows by Doppler Wind Lidar: Issues and Preliminary Recommendations

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

    Remote Sensing of Complex Flows by Doppler Wind Lidar: Issues and Preliminary Recommendations Lead Author: Andrew Clifton National Renewable Energy Laboratory Technical Report NREL/TP-5000-64634 December 2015 NREL is a national laboratory of the U.S. Department of Energy Office of Energy Efficiency & Renewable Energy Operated by the Alliance for Sustainable Energy, LLC This report is available at no cost from the National Renewable Energy Laboratory (NREL) at www.nrel.gov/publications.

  13. Precision Model Independent Determination of vertical bar V{sub ub} vertical bar from B{yields}{pi}l{nu}

    SciTech Connect (OSTI)

    Arnesen, Christian M.; Stewart, Iain W.; Grinstein, Benjamin; Rothstein, Ira Z.

    2005-08-12

    A precision method for determining vertical bar V{sub ub} vertical bar using the full range in q{sup 2} of B{yields}{pi}l{nu} data is presented. At large q{sup 2} the form factor is taken from unquenched lattice QCD, at q{sup 2}=0 we impose a model independent constraint obtained from B{yields}{pi}{pi} using the soft-collinear effective theory, and the shape is constrained using QCD dispersion relations. We find vertical bar V{sub ub} vertical bar=(3.54{+-}0.17{+-}0.44)x10{sup -3}. With 5% experimental error and 12% theory error, this is competitive with inclusive methods. Theory error is dominated by the input points, with negligible uncertainty from the dispersion relations.

  14. 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.

  15. Application of Raman spectroscopy to high-temperature analytical measurements

    SciTech Connect (OSTI)

    Young, J.P.; Dai, S.; Lee, Y.; Xizo, H.

    1997-01-01

    There are numerous analytical applications of scatter-emission and/or absorption spectroscopy applied to liquids and solids at 0 to 350 C. This paper describes an all-silica fiberoptic probe which is useful for spectral analyses from 0 to 1600 K and can be used in harsh chemical environments. The probe has been used for Raman spectral analyses of many molten salt and solid material systems to 1000 C. It has applications for such studies at higher temperature ranges. The instrumentation required along with the demonstrated and proposed applications of the all-silica probe are presented and discussed.

  16. Saturation of the leading spike growth in backward Raman amplifiers

    SciTech Connect (OSTI)

    Malkin, V. M.; Fisch, N. J.; Toroker, Z.

    2014-09-15

    Backward Raman amplification of laser pulses in plasmas can produce nearly relativistic unfocused output intensities and multi-exawatt powers in compact devices. The largest achievable intensity depends on which of major competitive processes set this limit. It is shown here that the relativistic electron nonlinearity can cause saturation of the leading amplified spike intensity before filamentation instabilities develop. A simple analytical model for the saturation, which supports numerical simulations, is suggested. The upper limit for the leading output spike unfocused intensity is calculated.

  17. Backward Raman amplification in the Langmuir wavebreaking regime

    SciTech Connect (OSTI)

    Toroker, Z.; Malkin, V. M.; Fisch, N. J.

    2014-11-15

    In plasma-based backward Raman amplifiers, the output pulse intensity increases with the input pump pulse intensity, as long as the Langmuir wave mediating energy transfer from the pump to the seed pulse remains intact. However, at high pump intensity, the Langmuir wave breaks, at which point the amplification efficiency may no longer increase with the pump intensity. Numerical simulations presented here, employing a one-dimensional Vlasov-Maxwell code, show that, although the amplification efficiency remains high when the pump only mildly exceeds the wavebreaking threshold, the efficiency drops precipitously at larger pump intensities.

  18. The efficiency of Raman amplification in the wavebreaking regime

    SciTech Connect (OSTI)

    Edwards, Matthew R. Mikhailova, Julia M.; Toroker, Zeev; Fisch, Nathaniel J.

    2015-07-15

    We compare previous analytic predictions, Vlasov-Maxwell simulations, and particle-in-cell results with a new set of comprehensive one and two dimensional particle-in-cell simulations in an effort to clarify apparent discrepancies between the predictions of different models for the efficiency of Raman amplification in the wavebreaking regime. We find reasonable agreement between our particle-in-cell simulations and previous results from Vlasov-Maxwell simulations and analytic work, suggesting a monotonic decrease in conversion efficiency for increased pump intensities past the wavebreaking threshold.

  19. MPL

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

    MPL and Raman lidar (thick) cloud optical depth retrievals using solar background signal (overcast cases) * Lidars can retrieve optical depth of thick clouds using solar...

  20. ARM Southern Great Plains

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

    System Radiometer Calibration Facility Equipment Repair Lab Main Office Raman Lidar Doppler Lidar and Radar Wind Profiler Ka-Band Scanning ARM Cloud Radar Ka-Zenith Radar...

  1. Raman scattering method and apparatus for measuring isotope ratios and isotopic abundances

    DOE Patents [OSTI]

    Harney, Robert C.; Bloom, Stewart D.

    1978-01-01

    Raman scattering is used to measure isotope ratios and/or isotopic abundances. A beam of quasi-monochromatic photons is directed onto the sample to be analyzed, and the resulting Raman-scattered photons are detected and counted for each isotopic species of interest. These photon counts are treated mathematically to yield the desired isotope ratios or isotopic abundances.

  2. A versatile femtosecond stimulated Raman spectroscopy setup with tunable pulses in the visible to near infrared

    SciTech Connect (OSTI)

    Zhu, Liangdong; Liu, Weimin; Fang, Chong

    2014-07-28

    We demonstrate a versatile and efficient setup to perform femtosecond stimulated Raman spectroscopy (FSRS). Technical innovations are implemented to achieve the wavelength tunability for both the picosecond narrowband Raman pump pulse and femtosecond broadband Raman probe pulse. Using a simplified one-grating scheme in a home-built second harmonic bandwidth compressor followed by a two-stage noncollinear optical parametric amplifier, we tune the Raman pump pulse from ca. 480 to 750 nm. To generate the suitable Raman probe pulse in tandem, we rely on our recently demonstrated broadband up-converted multicolor array technique that readily provides tunable broadband laser sidebands across the visible to near-infrared range. This unique setup has unparalleled flexibility for conducting FSRS. We measure the ground-state Raman spectra of a cyclohexane standard using tunable pump-probe pairs at various wavelengths across the visible region. The best spectral resolution is ∼12 cm{sup −1}. By tuning the pump wavelength closer to the electronic absorption band of a photoacid pyranine in water, we observe the pre-resonantly enhanced Raman signal. The stimulated Raman gain of the 1627 cm{sup −1} mode is increased by over 15 times.

  3. UV resonance Raman characterization of polycyclic aromatic hydrocarbons in coal liquid distillates

    SciTech Connect (OSTI)

    Rumelfanger, R.; Asher, S.A.; Perry, M.B.

    1988-02-01

    Ultraviolet resonance Raman spectroscopy has been used to characterize the polycyclic aromatic hydrocarbon composition of a series of distillates of coal-derived liquids. The UV Raman spectra easily monitor changes in the polycyclic aromatic hydrocarbon composition as a function of distillation temperature. Specific species, such as pyrene, can be determined by judicious choice of excitation wavelength.

  4. Raman measurements in silica glasses irradiated with energetic ions

    SciTech Connect (OSTI)

    Saavedra, R. Martin, P.; Vila, R.; León, M.; Jiménez-Rey, D.; Girard, S.; Boukenter, A.; Ouerdane, Y.

    2014-10-21

    Ion irradiation with energetic He{sup +} (2.5 MeV), O{sup 4+} (13.5 MeV), Si{sup 4+} (24.4 MeV) and Cu{sup 7+} (32.6 MeV) species at several fluences (from 5 × 10{sup 12} to 1.65 × 10{sup 15} ion/cm{sup 2}) were performed in three types of SiO{sub 2} glasses with different OH content (KU1, KS-4V and Infrasil 301). After ion implantation the Raman spectra were measured and compared with the spectra of unirradiated samples. Irradiated samples of the three fused silica grades exhibit changes in the broad and asymmetric R-band (ω{sub 1} around 445 cm{sup −1}), in D{sub 1} (490 cm−1) and D{sub 2} (605 cm{sup −1}) bands associated to small-membered rings. The D{sub 2} band shows an increase with increasing fluences for different ions, indicating structural changes. Raman spectra of ion-irradiated samples were compared with the spectra of neutron irradiated samples at fluences 10{sup 17} n/cm{sup 2} and 1018 n/cm{sup 2}. Macroscopic surface cracking was detected, mainly at fluences corresponding to deposited energies between 10{sup 23} eV/cm{sup 3} and 10{sup 24} eV/cm{sup 3} (after ion beam shutdown)

  5. Surface-Enhanced Raman Optical Data Storage system

    DOE Patents [OSTI]

    Vo-Dinh, T.

    1994-06-28

    An improved Surface-Enhanced Raman Optical Data Storage System (SERODS) is disclosed. In the improved system, entities capable of existing in multiple reversible states are present on the storage device. Such entities result in changed Surface-Enhanced Raman Scattering (SERS) when localized state changes are effected in less than all of the entities. Therefore, by changing the state of entities in localized regions of a storage device, the SERS emissions in such regions will be changed. When a write-on device is controlled by a data signal, such a localized regions of changed SERS emissions will correspond to the data written on the device. The data may be read by illuminating the surface of the storage device with electromagnetic radiation of an appropriate frequency and detecting the corresponding SERS emissions. Data may be deleted by reversing the state changes of entities in regions where the data was initially written. In application, entities may be individual molecules which allows for the writing of data at the molecular level. A read/write/delete head utilizing near-field quantum techniques can provide for a write/read/delete device capable of effecting state changes in individual molecules, thus providing for the effective storage of data at the molecular level. 18 figures.

  6. Surface-enhanced raman optical data storage system

    DOE Patents [OSTI]

    Vo-Dinh, Tuan

    1994-01-01

    An improved Surface-Enhanced Raman Optical Data Storage System (SERODS) is disclosed. In the improved system, entities capable of existing in multiple reversible states are present on the storage device. Such entities result in changed Surface-Enhanced Raman Scattering (SERS) when localized state changes are effected in less than all of the entities. Therefore, by changing the state of entities in localized regions of a storage device, the SERS emissions in such regions will be changed. When a write-on device is controlled by a data signal, such a localized regions of changed SERS emissions will correspond to the data written on the device. The data may be read by illuminating the surface of the storage device with electromagnetic radiation of an appropriate frequency and detecting the corresponding SERS emissions. Data may be deleted by reversing the state changes of entities in regions where the data was initially written. In application, entities may be individual molecules which allows for the writing of data at the molecular level. A read/write/delete head utilizing near-field quantum techniques can provide for a write/read/delete device capable of effecting state changes in individual molecules, thus providing for the effective storage of data at the molecular level.

  7. 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

  8. Raman spectroscopic characterization of the core-rim structure in reaction bonded boron carbide ceramics

    SciTech Connect (OSTI)

    Jannotti, Phillip; Subhash, Ghatu; Zheng, James Q.; Halls, Virginia; Karandikar, Prashant G.; Salamone, S.; Aghajanian, Michael K.

    2015-01-26

    Raman spectroscopy was used to characterize the microstructure of reaction bonded boron carbide ceramics. Compositional and structural gradation in the silicon-doped boron carbide phase (rim), which develops around the parent boron carbide region (core) due to the reaction between silicon and boron carbide, was evaluated using changes in Raman peak position and intensity. Peak shifting and intensity variation from the core to the rim region was attributed to changes in the boron carbide crystal structure based on experimental Raman observations and ab initio calculations reported in literature. The results were consistent with compositional analysis determined by energy dispersive spectroscopy. The Raman analysis revealed the substitution of silicon atoms first into the linear 3-atom chain, and then into icosahedral units of the boron carbide structure. Thus, micro-Raman spectroscopy provided a non-destructive means of identifying the preferential positions of Si atoms in the boron carbide lattice.

  9. Saturation mechanisms of backward stimulated Raman scattering in a one-dimensional geometry

    SciTech Connect (OSTI)

    Friou, A.; Bénisti, D.; Gremillet, L.; Lefebvre, E.; Morice, O.; Siminos, E.; Strozzi, D. J.

    2013-10-15

    In this paper, we investigate the saturation mechanisms of backward stimulated Raman scattering (BSRS) induced by nonlinear kinetic effects. In particular, we stress the importance of accounting for both the nonlinear frequency shift of the electron plasma wave and the growth of sidebands, in order to understand what stops the coherent growth of Raman scattering. Using a Bernstein-Greene-Kruskal approach, we provide an estimate for the maximum amplitude reached by a BSRS-driven plasma wave after the phase of monotonic growth. This estimate is in very good agreement with the results from kinetic simulations of stimulated Raman scattering using both a Vlasov and a Particle in Cell code. Our analysis, which may be generalized to a multidimensional geometry, should provide a means to estimate the limits of backward Raman amplification or the effectiveness of strategies that aim at strongly reducing Raman reflectivity in a fusion plasma.

  10. Multi-wavelength Raman scattering of nanostructured Al-doped zinc oxide

    SciTech Connect (OSTI)

    Russo, V.; Ghidelli, M.; Gondoni, P.

    2014-02-21

    In this work we present a detailed Raman scattering investigation of zinc oxide and aluminum-doped zinc oxide (AZO) films characterized by a variety of nanoscale structures and morphologies and synthesized by pulsed laser deposition under different oxygen pressure conditions. The comparison of Raman spectra for pure ZnO and AZO films with similar morphology at the nano/mesoscale allows to investigate the relation between Raman features (peak or band positions, width, relative intensity) and material properties such as local structural order, stoichiometry, and doping. Moreover Raman measurements with three different excitation lines (532, 457, and 325 nm) point out a strong correlation between vibrational and electronic properties. This observation confirms the relevance of a multi-wavelength Raman investigation to obtain a complete structural characterization of advanced doped oxide materials.

  11. Weather Research and Forecasting Model with Vertical Nesting Capability

    Energy Science and Technology Software Center (OSTI)

    2014-08-01

    The Weather Research and Forecasting (WRF) model with vertical nesting capability is an extension of the WRF model, which is available in the public domain, from www.wrf-model.org. The new code modifies the nesting procedure, which passes lateral boundary conditions between computational domains in the WRF model. Previously, the same vertical grid was required on all domains, while the new code allows different vertical grids to be used on concurrently run domains. This new functionality improvesmore » WRF's ability to produce high-resolution simulations of the atmosphere by allowing a wider range of scales to be efficiently resolved and more accurate lateral boundary conditions to be provided through the nesting procedure.« less

  12. Cloud-Scale Vertical Velocity and Turbulent Dissipation Rate Retrievals

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

    Shupe, Matthew

    Time-height fields of retrieved in-cloud vertical wind velocity and turbulent dissipation rate, both retrieved primarily from vertically-pointing, Ka-band cloud radar measurements. Files are available for manually-selected, stratiform, mixed-phase cloud cases observed at the North Slope of Alaska (NSA) site during periods covering the Mixed-Phase Arctic Cloud Experiment (MPACE, late September through early November 2004) and the Indirect and Semi-Direct Aerosol Campaign (ISDAC, April-early May 2008). These time periods will be expanded in a future submission.

  13. Vertical-cavity surface-emitting laser device

    DOE Patents [OSTI]

    Hadley, G. Ronald; Lear, Kevin L.; Awyoung, Adelbert; Choquette, Kent D.

    1999-01-01

    A vertical-cavity surface-emitting laser device. The vertical-cavity surface-emitting laser (VCSEL) device comprises one or more VCSELs with each VCSEL having a mode-control region thereabout, with the mode-control region forming an optical cavity with an effective cavity length different from the effective cavity length within each VCSEL. Embodiments of the present invention can be formed as single VCSELs and as one- or two-dimensional arrays of VCSELs, with either an index-guided mode of operation or an index anti-guided mode of operation being defined by a sign of the difference in the two effective cavity lengths.

  14. Cloud-Scale Vertical Velocity and Turbulent Dissipation Rate Retrievals

    SciTech Connect (OSTI)

    Shupe, Matthew

    2013-05-22

    Time-height fields of retrieved in-cloud vertical wind velocity and turbulent dissipation rate, both retrieved primarily from vertically-pointing, Ka-band cloud radar measurements. Files are available for manually-selected, stratiform, mixed-phase cloud cases observed at the North Slope of Alaska (NSA) site during periods covering the Mixed-Phase Arctic Cloud Experiment (MPACE, late September through early November 2004) and the Indirect and Semi-Direct Aerosol Campaign (ISDAC, April-early May 2008). These time periods will be expanded in a future submission.

  15. Evaluating Global Aerosol Models and Aerosol and Water Vapor Properties Near Clouds

    SciTech Connect (OSTI)

    Turner, David, D.; Ferrare, Richard, A.

    2011-07-06

    The 'Evaluating Global Aerosol Models and Aerosol and Water Vapor Properties Near Clouds' project focused extensively on the analysis and utilization of water vapor and aerosol profiles derived from the ARM Raman lidar at the Southern Great Plains ARM site. A wide range of different tasks were performed during this project, all of which improved quality of the data products derived from the lidar or advanced the understanding of atmospheric processes over the site. These activities included: upgrading the Raman lidar to improve its sensitivity; participating in field experiments to validate the lidar aerosol and water vapor retrievals; using the lidar aerosol profiles to evaluate the accuracy of the vertical distribution of aerosols in global aerosol model simulations; examining the correlation between relative humidity and aerosol extinction, and how these change, due to horizontal distance away from cumulus clouds; inferring boundary layer turbulence structure in convective boundary layers from the high-time-resolution lidar water vapor measurements; retrieving cumulus entrainment rates in boundary layer cumulus clouds; and participating in a field experiment that provided data to help validate both the entrainment rate retrievals and the turbulent profiles derived from lidar observations.

  16. Confocal volume in laser Raman microscopy depth profiling

    SciTech Connect (OSTI)

    Maruyama, Yutaka; Kanematsu, Wataru

    2011-11-15

    To clarify the degradation of confocality in laser Raman microscopy depth profiling (optical sectioning) and the influence of pinhole filtering on it, we investigate the confocal volume in detail based on Gaussian beam optics and scalar wave optics. Theoretical depth profiles of a homogeneous transparent sample for four different pinhole sizes, which are computed using the measured incident beam waist radius w{sub 0} and only a few optical system specific parameters such as a numerical aperture (NA) and a focal length, show a good agreement with the corresponding measured depth profiles. The computed confocal volume demonstrates that the pinhole size affects the actual probe depth as well as the axial resolution and the total intensity loss.

  17. Surface enhanced Raman gene probe and methods thereof

    DOE Patents [OSTI]

    Vo-Dinh, T.

    1998-07-21

    The subject invention disclosed is a new gene probe biosensor and methods based on surface enhanced Raman scattering (SERS) label detection. The SER gene probe biosensor comprises a support means, a SER gene probe having at least one oligonucleotide strand labeled with at least one SERS label, and a SERS active substrate disposed on the support means and having at least one of the SER gene probes adsorbed. Biotargets such as bacterial and viral DNA, RNA and PNA are detected using a SER gene probe via hybridization to oligonucleotide strands complementary to the SER gene probe. The support means supporting the SERS active substrate includes a fiberoptic probe, an array of fiberoptic probes for performance of multiple assays and a waveguide microsensor array with charge-coupled devices or photodiode arrays. 18 figs.

  18. Surface enhanced Raman gene probe and methods thereof

    DOE Patents [OSTI]

    Vo-Dinh, Tuan

    1998-01-01

    The subject invention disclosed herein is a new gene probe biosensor and methods thereof based on surface enhanced Raman scattering (SERS) label detection. The SER gene probe biosensor comprises a support means, a SER gene probe having at least one oligonucleotide strand labeled with at least one SERS label, and a SERS active substrate disposed on the support means and having at least one of the SER gene probes adsorbed thereon. Biotargets such as bacterial and viral DNA, RNA and PNA are detected using a SER gene probe via hybridization to oligonucleotide strands complementary to the SER gene probe. The support means supporting the SERS active substrate includes a fiberoptic probe, an array of fiberoptic probes for performance of multiple assays and a waveguide microsensor array with charge-coupled devices or photodiode arrays.

  19. Stimulated Raman adiabatic passage in an extended ladder system

    SciTech Connect (OSTI)

    Niu Yingyu; Wang Rong; Qiu Minghui [School of Science, Dalian Jiaotong University, Dalian 116028 (China)

    2011-08-15

    The rovibrational dynamics of an extended ladder stimulated Raman adiabatic passage (STIRAP) system through permanent dipole moment transitions is investigated theoretically using the time-dependent quantum-wave-packet method for the ground electronic state of the HF molecule. The calculated results show that nearly 100% of the population can be transferred to the target state through (1+2), (1+3), and (2+2) STIRAP schemes. By choosing a suitable excitation pathway, the effects of the background states on the final population of the target state can be removed. For the multiphoton STIRAP process, the one-photon overtone pump scheme is more efficient than the two-photon pump scheme in controlling the population transfer to the target state.

  20. Raman scattering from superhard rhenium diboride under high pressure

    SciTech Connect (OSTI)

    Xie, Miao; Winkler, Björn; Mao, Zhu; Kaner, Richard B.; Tolbert, Sarah H. E-mail: tolbert@chem.ucla.edu; Kavner, Abby E-mail: tolbert@chem.ucla.edu

    2014-01-06

    Lattice vibrational properties of superhard rhenium diboride (ReB{sub 2}) were examined up to 8 GPa in a diamond anvil cell using Raman spectroscopy techniques. Linear pressure coefficients and mode Grüneisen parameters are obtained. Good agreement is found between the experimental and theoretical calculated Grüneisen parameters. Examination of the calculated mode Grüneisen parameters reveals that both B-B and Re-B covalent bonds play a dominant role in supporting the applied load under pressure. A comparison of vibrations parallel and perpendicular to the c-axis indicates that bonds along the c-axis tend to take greater loads. Our results agree with observations of elastic lattice anisotropy obtained from both in situ X-ray diffraction measurements and ultrasonic resonance spectra.

  1. High-pressure Raman spectroscopy of phase change materials

    SciTech Connect (OSTI)

    Hsieh, Wen-Pin Mao, Wendy L.; Zalden, Peter; Wuttig, Matthias; Lindenberg, Aaron M.

    2013-11-04

    We used high-pressure Raman spectroscopy to study the evolution of vibrational frequencies of the phase change materials (PCMs) Ge{sub 2}Sb{sub 2}Te{sub 5}, GeSb{sub 2}Te{sub 4}, and SnSb{sub 2}Te{sub 4}. We found that the critical pressure for triggering amorphization in the PCMs decreases with increasing vacancy concentration, demonstrating that the presence of vacancies, rather than differences in the atomic covalent radii, is crucial for pressure-induced amorphization in PCMs. Compared to the as-deposited amorphous phase, the pressure-induced amorphous phase has a similar vibrational spectrum but requires much lower laser power to transform into the crystalline phase, suggesting different kinetics of crystallization, which may have implications for applications of PCMs in non-volatile data storage.

  2. Multiphonon resonant Raman scattering in MoS{sub 2}

    SciTech Connect (OSTI)

    Gołasa, K. Grzeszczyk, M.; Wysmołek, A.; Babiński, A.; Leszczyński, P.; Faugeras, C.; Nicolet, A. A. L.; Potemski, M.

    2014-03-03

    Optical emission spectrum of a resonantly (λ = 632.8 nm) excited molybdenum disulfide (MoS{sub 2}) is studied at liquid helium temperature. More than 20 peaks in the energy range spanning up to 1400 cm{sup −1} from the laser line, which are related to multiphonon resonant Raman scattering processes, are observed. The attribution of the observed lines involving basic lattice vibrational modes of MoS{sub 2} and both the longitudinal (LA(M)) and the transverse (TA(M) and/or ZA(M)) acoustic phonons from the vicinity of the high-symmetry M point of the MoS{sub 2} Brillouin zone is proposed.

  3. Detection of volatile organic compounds using surface enhanced Raman scattering

    SciTech Connect (OSTI)

    Chang, A S; Maiti, A; Ileri, N; Bora, M; Larson, C C; Britten, J A; Bond, T C

    2012-03-22

    The authors present the detection of volatile organic compounds directly in their vapor phase by surface-enhanced Raman scattering (SERS) substrates based on lithographically-defined two-dimensional rectangular array of nanopillars. The type of nanopillars is known as the tapered pillars. For the tapered pillars, SERS enhancement arises from the nanofocusing effect due to the sharp tip on top. SERS experiments were carried out on these substrates using various concentrations of toluene vapor. The results show that SERS signal from a toluene vapor concentration of ppm level can be achieved, and the toluene vapor can be detected within minutes of exposing the SERS substrate to the vapor. A simple adsorption model is developed which gives results matching the experimental data. The results also show promising potential for the use of these substrates in environmental monitoring of gases and vapors.

  4. Q-branch Raman scattering and modern kinetic thoery

    SciTech Connect (OSTI)

    Monchick, L.

    1993-12-01

    The program is an extension of previous APL work whose general aim was to calculate line shapes of nearly resonant isolated line transitions with solutions of a popular quantum kinetic equation-the Waldmann-Snider equation-using well known advanced solution techniques developed for the classical Boltzmann equation. The advanced techniques explored have been a BGK type approximation, which is termed the Generalized Hess Method (GHM), and conversion of the collision operator to a block diagonal matrix of symmetric collision kernels which then can be approximated by discrete ordinate methods. The latter method, which is termed the Collision Kernel method (CC), is capable of the highest accuracy and has been used quite successfully for Q-branch Raman scattering. The GHM method, not quite as accurate, is applicable over a wider range of pressures and has proven quite useful.

  5. Nanosensors based on functionalized nanoparticles and surface enhanced raman scattering

    DOE Patents [OSTI]

    Talley, Chad E.; Huser, Thomas R.; Hollars, Christopher W.; Lane, Stephen M.; Satcher, Jr., Joe H.; Hart, Bradley R.; Laurence, Ted A.

    2007-11-27

    Surface-Enhanced Raman Spectroscopy (SERS) is a vibrational spectroscopic technique that utilizes metal surfaces to provide enhanced signals of several orders of magnitude. When molecules of interest are attached to designed metal nanoparticles, a SERS signal is attainable with single molecule detection limits. This provides an ultrasensitive means of detecting the presence of molecules. By using selective chemistries, metal nanoparticles can be functionalized to provide a unique signal upon analyte binding. Moreover, by using measurement techniques, such as, ratiometric received SERS spectra, such metal nanoparticles can be used to monitor dynamic processes in addition to static binding events. Accordingly, such nanoparticles can be used as nanosensors for a wide range of chemicals in fluid, gaseous and solid form, environmental sensors for pH, ion concentration, temperature, etc., and biological sensors for proteins, DNA, RNA, etc.

  6. Surface enhanced Raman gene probe and methods thereof

    DOE Patents [OSTI]

    Vo-Dinh, T.

    1998-02-24

    The subject invention disclosed is a new gene probe biosensor and methods based on surface enhanced Raman scattering (SERS) label detection. The SER gene probe biosensor comprises a support means, a SER gene probe having at least one oligonucleotide strand labeled with at least one SERS label, and a SERS active substrate disposed on the support means and having at least one of the SER gene probes adsorbed thereon. Biotargets such as bacterial and viral DNA, RNA and PNA are detected using a SER gene probe via hybridization to oligonucleotide strands complementary to the SER gene probe. The support means includes a fiberoptic probe, an array of fiberoptic probes for performance of multiple assays and a waveguide microsensor array with charge-coupled devices or photodiode arrays. 18 figs.

  7. Surface enhanced Raman gene probe and methods thereof

    DOE Patents [OSTI]

    Vo-Dinh, T.

    1998-09-29

    The subject invention disclosed herein is a new gene probe biosensor and methods based on surface enhanced Raman scattering (SERS) label detection. The SER gene probe biosensor comprises a support means, a SER gene probe having at least one oligonucleotide strand labeled with at least one SERS label, and a SERS active substrate disposed on the support means and having at least one of the SER gene probes adsorbed thereon. Biotargets such as bacterial and viral DNA, RNA and PNA are detected using a SER gene probe via hybridization to oligonucleotide strands complementary to the SER gene probe. The support means supporting the SERS active substrate includes a fiberoptic probe, an array of fiberoptic probes for performance of multiple assays and a waveguide microsensor array with charge-coupled devices or photodiode arrays. 18 figs.

  8. Cryogenic infrastructure for Fermilab's ILC vertical cavity test facility

    SciTech Connect (OSTI)

    Carcagno, R.; Ginsburg, C.; Huang, Y.; Norris, B.; Ozelis, J.; Peterson, T.; Poloubotko, V.; Rabehl, R.; Sylvester, C.; Wong, M.; /Fermilab

    2006-06-01

    Fermilab is building a Vertical Cavity Test Facility (VCTF) to provide for R&D and pre-production testing of bare 9-cell, 1.3-GHz superconducting RF (SRF) cavities for the International Linear Collider (ILC) program. This facility is located in the existing Industrial Building 1 (IB1) where the Magnet Test Facility (MTF) also resides. Helium and nitrogen cryogenics are shared between the VCTF and MTF including the existing 1500-W at 4.5-K helium refrigerator with vacuum pumping for super-fluid operation (125-W capacity at 2-K). The VCTF is being constructed in multiple phases. The first phase is scheduled for completion in mid 2007, and includes modifications to the IB1 cryogenic infrastructure to allow helium cooling to be directed to either the VCTF or MTF as scheduling demands require. At this stage, the VCTF consists of one Vertical Test Stand (VTS) cryostat for the testing of one cavity in a 2-K helium bath. Planning is underway to provide a total of three Vertical Test Stands at VCTF, each capable of accommodating two cavities. Cryogenic infrastructure improvements necessary to support these additional VCTF test stands include a dedicated ambient temperature vacuum pump, a new helium purification skid, and the addition of helium gas storage. This paper describes the system design and initial cryogenic operation results for the first VCTF phase, and outlines future cryogenic infrastructure upgrade plans for expanding to three Vertical Test Stands.

  9. Aligned vertical fractures, HTI reservoir symmetry, and Thomsenseismic anisotropy parameters

    SciTech Connect (OSTI)

    Berryman, James G.

    2007-06-27

    The Sayers and Kachanov (1991) crack-influence parametersare shown to be directly related to Thomsen (1986) weak-anisotropyseismic parameters for fractured reservoirs when the crack density issmall enough. These results are then applied to seismic wave propagationin reservoirs having HTI symmetry due to aligned vertical fractures. Theapproach suggests a method of inverting for fracture density from wavespeed data.

  10. Cryogenic vertical test facility for the SRF cavities at BNL

    SciTech Connect (OSTI)

    Than, R.; Liaw, CJ; Porqueddu, R.; Grau, M.; Tuozzolo, J.; Tallerico, T.; McIntyre, G.; Lederle, D.; Ben-Zvi, I.; Burrill, A.; Pate, D.

    2011-03-28

    A vertical test facility has been constructed to test SRF cavities and can be utilized for other applications. The liquid helium volume for the large vertical dewar is approximate 2.1m tall by 1m diameter with a clearance inner diameter of 0.95m after the inner cold magnetic shield installed. For radiation enclosure, the test dewar is located inside a concrete block structure. The structure is above ground, accessible from the top, and equipped with a retractable concrete roof. A second radiation concrete facility, with ground level access via a labyrinth, is also available for testing smaller cavities in 2 smaller dewars. The cryogenic transfer lines installation between the large vertical test dewar and the cryo plant's sub components is currently near completion. Controls and instrumentations wiring are also nearing completion. The Vertical Test Facility will allow onsite testing of SRF cavities with a maximum overall envelope of 0.9 m diameter and 2.1 m height in the large dewar and smaller SRF cavities and assemblies with a maximum overall envelope of 0.66 m diameter and 1.6 m height.

  11. Novel vertical silicon photodiodes based on salicided polysilicon trenched contacts

    SciTech Connect (OSTI)

    Kaminski, Yelena; Shauly, Eitan; Paz, Yaron

    2015-12-07

    The classical concept of silicon photodiodes comprises of a planar design characterized by heavily doped emitters. Such geometry has low collection efficiency of the photons absorbed close to the surface. An alternative, promising, approach is to use a vertical design. Nevertheless, realization of such design is technologically challenged, hence hardly explored. Herein, a novel type of silicon photodiodes, based on salicided polysilicon trenched contacts, is presented. These contacts can be prepared up to 10 μm in depth, without showing any leakage current associated with the increase in the contact area. Consequently, the trenched photodiodes revealed better performance than no-trench photodiodes. A simple two dimensional model was developed, allowing to estimate the conditions under which a vertical design has the potential to have better performance than that of a planar design. At large, the deeper the trench is, the better is the vertical design relative to the planar (up to 10 μm for silicon). The vertical design is more advantageous for materials characterized by short diffusion lengths of the carriers. Salicided polysilicon trenched contacts open new opportunities for the design of solar cells and image sensors. For example, these contacts may passivate high contact area buried contacts, by virtue of the conformity of polysilicon interlayer, thus lowering the via resistance induced recombination enhancement effect.

  12. Femtosecond stimulated Raman spectroscopy by six-wave mixing

    SciTech Connect (OSTI)

    Molesky, Brian P.; Guo, Zhenkun; Moran, Andrew M.

    2015-06-07

    Femtosecond Stimulated Raman Spectroscopy (FSRS) is motivated by the knowledge of the molecular geometry changes that accompany sub-picosecond chemical reactions. The detection of vibrational resonances throughout the entire fingerprint region of the spectrum with sub-100-fs delay precision is fairly straightforward to accomplish with the FSRS technique. Despite its utility, FSRS must contend with substantial technical challenges that stem from a large background of residual laser light and lower-order nonlinearities when all laser pulses are electronically resonant with the equilibrium system. In this work, a geometry based on five incident laser beams is used to eliminate much of this undesired background in experiments conducted on metmyoglobin. Compared to a three-beam FSRS geometry with all electronically resonant laser pulses, the five-beam approach described here offers major improvements in the data acquisition rate, sensitivity, and background suppression. The susceptibility of the five-beam geometry to experimental artifacts is investigated using control experiments and model calculations. Of particular concern are undesired cascades of third-order nonlinearities, which are known to challenge FSRS measurements carried out on electronically off-resonant systems. It is generally understood that “forbidden” steps in the desired nonlinear optical processes are the origin of the problems encountered under off-resonant conditions. In contrast, the present experiments are carried out under electronically resonant conditions, where such unfortunate selection rules do not apply. Nonetheless, control experiments based on spectroscopic line shapes, signal phases, and sample concentrations are conducted to rule out significant contributions from cascades of third-order processes. Theoretical calculations are further used to estimate the relative intensities of the direct and cascaded responses. Overall, the control experiments and model calculations presented in

  13. Synthesis and characterization of mixed monolayer protected gold nanorods and their Raman activities

    SciTech Connect (OSTI)

    Mlambo, Mbuso; Mdluli, Phumlani S.; Shumbula, Poslet; Mpelane, Siyasanga; Moloto, Nosipho; Skepu, Amanda; Tshikhudo, Robert

    2013-10-15

    Graphical abstract: Gold nanorods surface functionalization. - Highlights: • Mixed monolayer protected gold nanorods. • Surface enhanced Raman spectroscopy. • HS-(CH{sub 2}){sub 11}-NHCO-coumarin as a Raman active compound. - Abstract: The cetyltrimethylammonium bromide (CTAB) gold nanorods (AuNRs) were prepared by seed-mediated route followed by the addition of a Raman active compound (HS-(CH{sub 2}){sub 11}-NHCO-coumarin) on the gold nanorods surfaces. Different stoichiometric mixtures of HS-(CH{sub 2}){sub 11}-NHCO-coumarin and HS-PEG-(CH{sub 2}){sub 11}COOH were evaluated for their Raman activities. The lowest stoichiometric ratio HS-(CH{sub 2}){sub 11}-NHCO-coumarin adsorbed on gold nanorods surface was detected and enhanced by Raman spectroscopy. The produced mixed monolayer protected gold nanorods were characterized by UV-vis spectrometer for optical properties, transmission electron microscope (TEM) for structural properties (shape and aspect ratio) and their zeta potentials (charges) were obtained from ZetaSizer to determine the stability of the produced mixed monolayer protected gold nanorods. The Raman results showed a surface enhanced Raman scattering (SERS) enhancement at the lowest stoichiometric ratio of 1% HS-(CH{sub 2}){sub 11}-NHCO-coumarin compared to high ratio of 50% HS-(CH{sub 2}){sub 11}-NHCO-coumarin on the surface of gold nanorods.

  14. Method And System For Examining Biological Materials Using Low Power Cw Excitation Raman Spectroscopy.

    DOE Patents [OSTI]

    Alfano, Robert R.; Wang, Wubao

    2003-05-06

    A method and system for examining biological materials using low-power cw excitation Raman spectroscopy. A low-power continuous wave (cw) pump laser beam and a low-power cw Stokes (or anti-Stokes) probe laser beam simultaneously illuminate a biological material and traverse the biological material in collinearity. The pump beam, whose frequency is varied, is used to induce Raman emission from the biological material. The intensity of the probe beam, whose frequency is kept constant, is monitored as it leaves the biological material. When the difference between the pump and probe excitation frequencies is equal to a Raman vibrational mode frequency of the biological material, the weak probe signal becomes amplified by one or more orders of magnitude (typically up to about 10.sup.4 -10.sup.6) due to the Raman emission from the pump beam. In this manner, by monitoring the intensity of the probe beam emitted from the biological material as the pump beam is varied in frequency, one can obtain an excitation Raman spectrum for the biological material tested. The present invention may be applied to in the in vivo and/or in vitro diagnosis of diabetes, heart disease, hepatitis, cancers and other diseases by measuring the characteristic excitation Raman lines of blood glucose, cholesterol, serum glutamic oxalacetic transaminase (SGOT)/serum glutamic pyruvic transaminase (SGPT), tissues and other corresponding Raman-active body constituents, respectively.

  15. 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.

  16. Method And System For Examining Biological Materials Using Low Power Cw Excitation Raman Spectroscopy.

    DOE Patents [OSTI]

    Alfano, Robert R.; Wang, Wubao

    2000-11-21

    A method and system for examining biological materials using low-power cw excitation Raman spectroscopy. In accordance with the teachings of the invention, a low-power continuous wave (cw) pump laser beam and a low-power cw Stokes (or anti-Stokes) probe laser beam simultaneously illuminate a biological material and traverse the biological material in collinearity. The pump beam, whose frequency is varied, is used to induce Raman emission from the biological material. The intensity of the probe beam, whose frequency is kept constant, is monitored as it leaves the biological material. When the difference between the pump and probe excitation frequencies is equal to a Raman vibrational mode frequency of the biological material, the weak probe signal becomes amplified by one or more orders of magnitude (typically up to about 10.sup.4 -10.sup.6) due to the Raman emission from the pump beam. In this manner, by monitoring the intensity of the probe beam emitted from the biological material as the pump beam is varied in frequency, one can obtain an excitation Raman spectrum for the biological material tested. The present invention may be applied to in the in vivo and/or in vitro diagnosis of diabetes, heart disease, hepatitis, cancers and other diseases by measuring the characteristic excitation Raman lines of blood glucose, cholesterol, serum glutamic oxalacetic transaminase (SGOT)/serum glutamic pyruvic tansaminase (SGPT), tissues and other corresponding Raman-active body constituents, respectively. For example, it may also be used to diagnose diseases associated with the concentration of Raman-active constituents in urine, lymph and saliva It may be used to identify cancer in the breast, cervix, uterus, ovaries and the like by measuring the fingerprint excitation Raman spectra of these tissues. It may also be used to reveal the growing of tumors or cancers by measuring the levels of nitric oxide in tissue.

  17. Study of lattice dynamics in yttrium doped NdMnO{sub 3} using Raman spectroscopy

    SciTech Connect (OSTI)

    Yadav, Ruchika Elizabeth, Suja; Nair, Harikrishnan S.

    2014-04-24

    A systematic study of Raman spectra on Yttrium doped NdMnO{sub 3} polycrystalline samples was undertaken to understand the lattice dynamics in this compound. Raman active phonons were analyzed and the observed peak were assigned to elucidate various phonon modes in the range (200 - 800) cm{sup −1}. It was observed that at 325 cm{sup −1} phonon frequency shifts upward as much as upto 4 % with increase in Yttrium content. Lattice distortions manifest themselves by frequency shifts in both bending and tilt modes of MnO{sub 6} octahedra, resulting in increase of Raman band line-widths.

  18. Raman spectroscopy of graphite in high magnetic fields: Electron-phonon coupling and magnetophonon resonance

    SciTech Connect (OSTI)

    Kim, Younghee; Smirnov, Dmitry; Kalugin, Nikolai G.; Lombardo, Antonio; Ferrari, Andrea C.

    2013-12-04

    The magneto-Raman measurements of graphite were performed in a back-scattering Faraday geometry at temperature 10 K in magnetic fields up to 45 T. The experimental data reveal the rich structure of Raman-active excitations dominated by K-point massive electrons. At high magnetic fields the graphite E{sub 2g} Raman line shows complex multi- component behavior interpreted as magnetophonon resonance coupled electron-phonon modes at graphite’s K-point. Also we found the clear signature of the fundamental, strongly dumped, n=0 magnetophonon resonance associated with H point massless holes.

  19. Nonlinear-optical spectral interferometry of nanostructures using coherent anti-Stokes Raman scattering

    SciTech Connect (OSTI)

    Konorov, Stanislav O; Mitrokhin, V P; Fedotov, Andrei B; Zheltikov, Aleksei M; Smirnova, I V; Sidorov-Biryukov, D A

    2005-01-31

    The spectrum of coherent anti-Stokes Raman scattering (CARS) from Raman-active vibrations of gas-phase nitrogen molecules in a mesoporous silica aerogel host is experimentally studied. The CARS spectral profile under these conditions is a result of interference of the resonant part of nonlinear susceptibility, originating from nitrogen molecules in aerogel pores, and the nonresonant contribution, related to the mesoporous host. Raman-active modes of gas-phase molecular nitrogen give rise to intense resonances in the CARS spectrum, serving as reference spectral profiles for probing local parameters of a nanocomposite material (nanoCARS). (laser applications and other topics in quantum electronics)

  20. Third harmonic stimulated Raman backscattering of laser in a magnetized plasma

    SciTech Connect (OSTI)

    Paknezhad, Alireza; Dorranian, Davoud

    2013-09-15

    This article studies the nonlinear Raman shifted third harmonic backscattering of an intense extraordinary laser wave through a homogenous transversely magnetized cold plasma. Due to the relativistic nonlinearity, the plasma dynamic is modified in the presence of transversely magnetic field, and this can generate the third harmonic scattered wave and an electrostatic upper hybrid wave via the Raman scattering process. Using the nonlinear wave equation, the mechanism of nonlinear third harmonic Raman scattering is discussed in detail to obtain the maximum growth rate of instability in the mildly relativistic regime. The growth rate decreases as the static magnetic field increases. It also increases with the pump wave amplitude.

  1. ARM - Field Campaign - AIRS Water Vapor Experiment - Ground ...

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

    ... Raman Lidar Yes Schmidlin Balloon-borne sounding system(s) Yes Hagan Laser Hygrometer Sonde Yes Lesht Surface Temperature and Relative Humidity Reference System Yes Turner Raman ...

  2. 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

  3. 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.

  4. Modeling LIDAR Detection of Biological Aerosols to Determine Optimum Implementation Strategy

    SciTech Connect (OSTI)

    Sheen, David M.; Aker, Pam M.

    2007-09-19

    This report summarizes work performed for a larger multi-laboratory project named the Background Interferent Measurement and Standards project. While originally tasked to develop algorithms to optimize biological warfare agent detection using UV fluorescence LIDAR, the current uncertainties in the reported fluorescence profiles and cross sections the development of any meaningful models. It was decided that a better approach would be to model the wavelength-dependent elastic backscattering from a number of ambient background aerosol types, and compare this with that generated from representative sporulated and vegetative bacterial systems. Calculations in this report show that a 266, 355, 532 and 1064 nm elastic backscatter LIDAR experiment will allow an operator to immediately recognize when sulfate, VOC-based or road dust (silicate) aerosols are approaching, independent of humidity changes. It will be more difficult to distinguish soot aerosols from biological aerosols, or vegetative bacteria from sporulated bacteria. In these latter cases, the elastic scattering data will most likely have to be combined with UV fluorescence data to enable a more robust categorization.

  5. Microsoft PowerPoint - ferrare_STM_2009_poster [Compatibility...

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

    ground (SGP Raman Lidar) and airborne (NASALaRC HSRL) lidars and * Lidar measurements ... Aerosol Variability Near Clouds During CLASICCHAPS 1 NASA LaRC; 2 SSAI; 3 Univ. of ...

  6. Analytic calculations of hyper-Raman spectra from density functional theory hyperpolarizability gradients

    SciTech Connect (OSTI)

    Ringholm, Magnus; Ruud, Kenneth; Bast, Radovan; Oggioni, Luca; Ekström, Ulf

    2014-10-07

    We present the first analytic calculations of the geometrical gradients of the first hyperpolarizability tensors at the density-functional theory (DFT) level. We use the analytically calculated hyperpolarizability gradients to explore the importance of electron correlation effects, as described by DFT, on hyper-Raman spectra. In particular, we calculate the hyper-Raman spectra of the all-trans and 11-cis isomers of retinal at the Hartree-Fock (HF) and density-functional levels of theory, also allowing us to explore the sensitivity of the hyper-Raman spectra on the geometrical characteristics of these structurally related molecules. We show that the HF results, using B3LYP-calculated vibrational frequencies and force fields, reproduce the experimental data for all-trans-retinal well, and that electron correlation effects are of minor importance for the hyper-Raman intensities.

  7. Multi-wavelength Raman spectroscopy study of supported vanadia catalysts: Structure identification and quantification

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

    Wu, Zili

    2014-10-20

    Revealing the structure of supported metal oxide catalysts is a prerequisite for establishing the structure - catalysis relationship. Among a variety of characterization techniques, multi-wavelength Raman spectroscopy, combining resonance Raman and non-resonance Raman with different excitation wavelengths, has recently emerged as a particularly powerful tool in not only identifying but also quantifying the structure of supported metal oxide clusters. In our review, we make use of two supported vanadia systems, VOx/SiO2 and VOx/CeO2, as examples to showcase how one can employ this technique to investigate the heterogeneous structure of active oxide clusters and to understand the complex interaction between themore » oxide clusters and the support. Moreover, the qualitative and quantitative structural information gained from the multi-wavelength Raman spectroscopy can be utilized to provide fundamental insights for designing more efficient supported metal oxide catalysts.« less

  8. Raman spectroscopy measurement of bilayer graphene's twist angle to boron nitride

    SciTech Connect (OSTI)

    Cheng, Bin; Wang, Peng; Pan, Cheng; Miao, Tengfei; Wu, Yong; Lau, C. N.; Bockrath, M.; Taniguchi, T.; Watanabe, K.

    2015-07-20

    When graphene is placed on hexagonal boron nitride with a twist angle, new properties develop due to the resulting moiré superlattice. Here, we report a method using Raman spectroscopy to make rapid, non-destructive measurements of the twist angle between bilayer graphene and hexagonal boron nitride. The lattice orientation is determined by using flakes with both bilayer and monolayer regions, and using the known Raman signature for the monolayer to measure the twist angle of the entire flake. The widths of the second order Raman peaks are found to vary linearly in the superlattice period and are used to determine the twist angle. The results are confirmed by using transport measurements to infer the superlattice period by the charge density required to reach the secondary resistance peaks. Small twist angles are also found to produce a significant modification of the first order Raman G band peak.

  9. Multi-wavelength Raman spectroscopy study of supported vanadia catalysts: Structure identification and quantification

    SciTech Connect (OSTI)

    Wu, Zili

    2014-10-20

    Revealing the structure of supported metal oxide catalysts is a prerequisite for establishing the structure - catalysis relationship. Among a variety of characterization techniques, multi-wavelength Raman spectroscopy, combining resonance Raman and non-resonance Raman with different excitation wavelengths, has recently emerged as a particularly powerful tool in not only identifying but also quantifying the structure of supported metal oxide clusters. In our review, we make use of two supported vanadia systems, VOx/SiO2 and VOx/CeO2, as examples to showcase how one can employ this technique to investigate the heterogeneous structure of active oxide clusters and to understand the complex interaction between the oxide clusters and the support. Moreover, the qualitative and quantitative structural information gained from the multi-wavelength Raman spectroscopy can be utilized to provide fundamental insights for designing more efficient supported metal oxide catalysts.

  10. Tetracyanoethylene oxide-functionalized graphene and graphite characterized by Raman and Auger spectroscopy

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

    Frolova, Liliya V.; Magedov, Igor V.; Harper, Aaron; Jha, Sanjiv K.; Ovezmyradov, Mekan; Chandler, Gary; Garcia, Jill; Bethke, Donald; Shaner, Eric A.; Vasiliev, Igor; et al

    2014-09-28

    The tetracyanoethylene oxide (TCNEO) functionalization of chemical vapor deposition grown large area graphene and graphite was performed using reaction of TCNEO with carbon surface in chlorobenzene. The successful functionalization has been confirmed by Raman and Auger spectroscopy, and by numerical modeling of the structure and vibrational modes of TCNEO-functionalized graphene. Raman spectra of TCNEO-functionalized graphene and graphite show several groups of lines corresponding to vibrations of attached carbonyl ylide. Lastly, one of key signatures of TCNEO attachment is the high intensity Raman band at ~1450 cm₋1, which represents the C-C=C in plane vibrations in functionalization-distorted graphene. We find Raman spectramore » indicate the existence of central (pristine) attachment of TCNEO to graphene surface.« less

  11. Tetracyanoethylene oxide-functionalized graphene and graphite characterized by Raman and Auger spectroscopy

    SciTech Connect (OSTI)

    Frolova, Liliya V.; Magedov, Igor V.; Harper, Aaron; Jha, Sanjiv K.; Ovezmyradov, Mekan; Chandler, Gary; Garcia, Jill; Bethke, Donald; Shaner, Eric A.; Vasiliev, Igor; Kalugin, Nikolai G.

    2014-09-28

    The tetracyanoethylene oxide (TCNEO) functionalization of chemical vapor deposition grown large area graphene and graphite was performed using reaction of TCNEO with carbon surface in chlorobenzene. The successful functionalization has been confirmed by Raman and Auger spectroscopy, and by numerical modeling of the structure and vibrational modes of TCNEO-functionalized graphene. Raman spectra of TCNEO-functionalized graphene and graphite show several groups of lines corresponding to vibrations of attached carbonyl ylide. Lastly, one of key signatures of TCNEO attachment is the high intensity Raman band at ~1450 cm₋1, which represents the C-C=C in plane vibrations in functionalization-distorted graphene. We find Raman spectra indicate the existence of central (pristine) attachment of TCNEO to graphene surface.

  12. Decoupling of epitaxial graphene via gold intercalation probed by dispersive Raman spectroscopy

    SciTech Connect (OSTI)

    Pillai, P. B. E-mail: m.desouza@sheffield.ac.uk; DeSouza, M. E-mail: m.desouza@sheffield.ac.uk; Narula, R.; Reich, S.; Wong, L. Y.; Batten, T.; Pokorny, J.

    2015-05-14

    Signatures of a superlattice structure composed of a quasi periodic arrangement of atomic gold clusters below an epitaxied graphene (EG) layer are examined using dispersive Raman spectroscopy. The gold-graphene system exhibits a laser excitation energy dependant red shift of the 2D mode as compared to pristine epitaxial graphene. The phonon dispersions in both the systems are mapped using the experimentally observed Raman signatures and a third-nearest neighbour tight binding electronic band structure model. Our results reveal that the observed excitation dependent Raman red shift in gold EG primarily arise from the modifications of the phonon dispersion in gold-graphene and shows that the extent of decoupling of graphene from the underlying SiC substrate can be monitored from the dispersive nature of the Raman 2D modes. The intercalated gold atoms restore the phonon band structure of epitaxial graphene towards free standing graphene.

  13. Mapping residual stress fields from Vickers hardness indents using Raman microprobe spectroscopy

    SciTech Connect (OSTI)

    Sparks, R.G.; Enloe, W.S.; Paesler, M.A.

    1988-12-01

    Micro-Raman spectroscopy is used to map the residual stress fields in the vicinity of Vickers hardness indents. Both 514.5 and 488.0 nm, light is used to excite the effect and the resulting shifted and broadened Raman peaks are analyzed using computer deconvolution. Half-wave plates are used to vary the orientation of the incident later light`s polarization state with respect to crystal orientation. The Raman scattered light is then analyzed for polarization dependences which are indicative of the various components of the Raman scattering tensor. Such studies can yield valuable information about the orientation of stress components in a well known stress field. The results can then be applied to the determination of stress components in machined semiconductor materials.

  14. Giant two-phonon Raman scattering from nanoscale NbC precipitates...

    Office of Scientific and Technical Information (OSTI)

    Giant two-phonon Raman scattering from nanoscale NbC precipitates in Nb Not Available Temp HTML Storage 2: Cao, C.; Tao, R.; Ford, D. C.; Klie, R. F.; Proslier, T.; Cooley, L. D.; ...

  15. Femtosecond pure-rotational coherent anti-stokes raman scattering gas phase diagnostics.

    SciTech Connect (OSTI)

    Kearney, Sean Patrick; Serrano, Justin Raymond

    2010-12-01

    We discuss recent experiments for the characterization of our femtosecond pure rotational CARS facility for observation of Raman transients in N{sub 2} and atmospheric air. The construction of a simplified femtosecond four-wave mixing system with only a single laser source is presented. Pure-rotational Raman transients reveal well-ordered time-domain recurrence peaks associated with the near-uniform spacing of rotational Raman peaks in the spectral domain. Long-time, 100-ps duration observations of the transient Raman polarization are presented, and the observed transients are compared to simulated results. Fourier transformation of the transients reveals two distinct sets of beat frequencies. Simulation results for temperatures from 300-700 K are used to illustrate the temperature sensitivity of the time-domain transients and their Fourier-transform counterparts. And strategies for diagnostics are briefly discussed. These results are being utilized to develop gas-phase measurement strategies for temperature and species concentration.

  16. 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.

  17. Friction of partially embedded vertically aligned carbon nanofibers inside elastomers

    SciTech Connect (OSTI)

    Aksak, Burak; Sitti, Metin; Cassell, Alan; Li, Jun; Meyyappan, Meyya; Callen, Phillip [NanoRobotics Laboratory, Department of Mechanical Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); NASA Ames Research Center, Moffett Field, California 94035 (United States); NASA Johnson Space Center, Houston, Texas 77058 (United States)

    2007-08-06

    Vertically aligned carbon nanofibers partially embedded inside polyurethane (eVACNFs) are proposed as a robust high friction fibrillar material with a compliant backing. Carbon nanofibers with 50-150 nm in diameter and 20-30 {mu}m in length are vertically grown on silicon and transferred completely inside an elastomer by vacuum molding. By using time controlled and selective oxygen plasma etching, fibers are partially released up to 5 {mu}m length. Macroscale friction experiments show that eVACNFs exhibit reproducible effective friction coefficients up to 1. Besides high friction, the proposed fabrication method improves fiber-substrate bond strength, and enables uniform height nanofibers with a compliant backing.

  18. Vertical stability requirements for ARIES-I reactor

    SciTech Connect (OSTI)

    Bathke, C.G.; Jardin, S.C.; Leuer, J.A.; Ward, D.J.; Princeton Univ., NJ . Plasma Physics Lab.; General Atomics, San Diego, CA; Princeton Univ., NJ . Plasma Physics Lab.)

    1989-01-01

    The vertical stability of the ARIES-I reactor design is analyzed with the NOVA-W, PSTAB, and TSC codes. A growth rate of {approximately}5.7 s{sup -1} is predicted for a vacuum vessel positioned behind the scrapeoff, first wall, and blanket (0.7 in inboard and 0.9 in outboard thickness) and acting as a passive stabilizer. A reactive power of {approximately}2 MV A would be required for active feedback coils located outside of the TF coils {approximately}3 m to correct a 50-mm vertical displacement of the magnetic axis. A multipolar expansion technique used in the TSC analysis is also used to examine options that minimize stored energy. 10 refs., 8 figs., 2 tabs.

  19. Aeroelastically coupled blades for vertical axis wind turbines

    DOE Patents [OSTI]

    Paquette, Joshua; Barone, Matthew F.

    2016-02-23

    Various technologies described herein pertain to a vertical axis wind turbine blade configured to rotate about a rotation axis. The vertical axis wind turbine blade includes at least an attachment segment, a rear swept segment, and optionally, a forward swept segment. The attachment segment is contiguous with the forward swept segment, and the forward swept segment is contiguous with the rear swept segment. The attachment segment includes a first portion of a centroid axis, the forward swept segment includes a second portion of the centroid axis, and the rear swept segment includes a third portion of the centroid axis. The second portion of the centroid axis is angularly displaced ahead of the first portion of the centroid axis and the third portion of the centroid axis is angularly displaced behind the first portion of the centroid axis in the direction of rotation about the rotation axis.

  20. Vertical-cavity surface-emitting laser device

    DOE Patents [OSTI]

    Hadley, G.R.; Lear, K.L.; Awyoung, A.; Choquette, K.D.

    1999-05-11

    A vertical-cavity surface-emitting laser device is disclosed. The vertical-cavity surface-emitting laser (VCSEL) device comprises one or more VCSELs with each VCSEL having a mode-control region thereabout, with the mode-control region forming an optical cavity with an effective cavity length different from the effective cavity length within each VCSEL. Embodiments of the present invention can be formed as single VCSELs and as one- or two-dimensional arrays of VCSELs, with either an index-guided mode of operation or an index anti-guided mode of operation being defined by a sign of the difference in the two effective cavity lengths. 10 figs.

  1. Taxel-addressable matrix of vertical nanowire piezotronic transistors

    SciTech Connect (OSTI)

    Wang, Zhong Lin; Wu, Wenzhuo; Wen, Xiaonan

    2015-05-05

    A tactile sensing matrix includes a substrate, a first plurality of elongated electrode structures, a plurality of vertically aligned piezoelectric members, an insulating layer infused into the piezoelectric members and a second plurality of elongated electrode structures. The first plurality of elongated electrode structures is disposed on the substrate along a first orientation. The vertically aligned piezoelectric members is disposed on the first plurality of elongated electrode structures and form a matrix having columns of piezoelectric members disposed along the first orientation and rows of piezoelectric members disposed along a second orientation that is transverse to the first orientation. The second plurality of elongated electrode structures is disposed on the insulating layer along the second orientation. The elongated electrode structures form a Schottky contact with the piezoelectric members. When pressure is applied to the piezoelectric members, current flow therethrough is modulated.

  2. 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.

  3. Operando Raman and Theoretical Vibration Spectroscopy of Non-PGM Catalysts

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

    | Department of Energy Operando Raman and Theoretical Vibration Spectroscopy of Non-PGM Catalysts Operando Raman and Theoretical Vibration Spectroscopy of Non-PGM Catalysts Presentation about spectroscopy techniques for non-platinum group metal (PGM) catalysts, presented by Eugene Smotkin, Northeastern University, at the kick-off meeting of the U.S. Department of Energy Fuel Cell Technologies Program's Catalysis Working Group, held May 14, 2012, in Arlington, Virginia.

  4. Summary of raman cone penetrometer probe waste tank radiation and chemical environment test

    SciTech Connect (OSTI)

    Reich, F.R.

    1996-09-27

    This report summarizes the results of testing Raman sapphire windows that were braze mounted into a mockup Raman probe head and stainless steel coupons in a simulated tank waste environment. The simulated environment was created by exposing sapphire window components, immersed in a tank simulant, in a gamma pit. This work was completed for the U.S. Department of Energy (DOE) Office of Environmental Management (EM-50) for Technical Task Proposal RL4-6-WT-21.

  5. Sandia vertical axis wind turbines (VAWTs) demonstrate offshore advantages

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

    vertical axis wind turbines (VAWTs) demonstrate offshore advantages - 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 Energy

  6. Determination of vertical profiles of aerosol extinction, single scatter

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

    albedo and asymmetry parameter at Barrow. Determination of vertical profiles of aerosol extinction, single scatter albedo and asymmetry parameter at Barrow. Sivaraman, Chitra Pacific Northwest National Laboratory Flynn, Connor Pacific Northwest National Laboratory Turner, David University of Wisconsin-Madison Category: Aerosols Efforts are currently underway to run and evaluate the Broadband Heating Rate Profile project at the ARM North Slope of Alaska (NSA) Barrow site for the time period

  7. Electrically injected visible vertical cavity surface emitting laser diodes

    DOE Patents [OSTI]

    Schneider, R.P.; Lott, J.A.

    1994-09-27

    Visible laser light output from an electrically injected vertical cavity surface emitting laser (VSCEL) diode is enabled by the addition of phase-matching spacer layers on either side of the active region to form the optical cavity. The spacer layers comprise InAlP which act as charge carrier confinement means. Distributed Bragg reflector layers are formed on either side of the optical cavity to act as mirrors. 5 figs.

  8. Electrically injected visible vertical cavity surface emitting laser diodes

    DOE Patents [OSTI]

    Schneider, Richard P.; Lott, James A.

    1994-01-01

    Visible laser light output from an electrically injected vertical cavity surface emitting laser (VSCEL) diode is enabled by the addition of phase-matching spacer layers on either side of the active region to form the optical cavity. The spacer layers comprise InAlP which act as charge carrier confinement means. Distributed Bragg reflector layers are formed on either side of the optical cavity to act as mirrors.

  9. Method of fabricating vertically aligned group III-V nanowires

    DOE Patents [OSTI]

    Wang, George T; Li, Qiming

    2014-11-25

    A top-down method of fabricating vertically aligned Group III-V micro- and nanowires uses a two-step etch process that adds a selective anisotropic wet etch after an initial plasma etch to remove the dry etch damage while enabling micro/nanowires with straight and smooth faceted sidewalls and controllable diameters independent of pitch. The method enables the fabrication of nanowire lasers, LEDs, and solar cells.

  10. Innovative Offshore Vertical-Axis Wind Turbine Rotors

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

    Offshore Vertical-Axis Wind Turbine Rotors - 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 Energy Defense Waste Management

  11. Assessing Cloud Spatial and Vertical Distribution with Infrared Cloud Analyzer

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

    Cloud Spatial and Vertical Distribution with Infrared Cloud Analyzer I. Genkova and C. N. Long Pacific Northwest National Laboratory Richland, Washington T. Besnard ATMOS SARL Le Mans, France D. Gillotay Institute d'Aeronomie Spatiale de Belgique Brussels, Belgium Introduction In the effort to resolve uncertainties about global climate change, the Atmospheric Radiation Measurement (ARM) Program (www.arm.gov) is improving the treatment of cloud radiative forcing and feedbacks in general

  12. ARM - Publications: Science Team Meeting Documents: Modeling the vertical

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

    profiles of aerosol characteristics and radiative impacts over the ARM sites Modeling the vertical profiles of aerosol characteristics and radiative impacts over the ARM sites Chuang, Catherine DOE/Lawrence Livermore National Laboratory Chin, Steve DOE/Lawrence Livermore National Laboratory Atmospheric aerosols play an important role in mediating the radiative balance of the Earth-atmosphere system. A global high-resolution aerosol modeling system developed by the Lawrence Livermore National

  13. Flow augmenters for vertical-axis windmills and turbines

    SciTech Connect (OSTI)

    Evans, F.C.

    1981-03-10

    A windmill is disclosed, the windmill including a vertical shaft mounted for rotation about its longitudinal axis, a number of blades spaced circumferentially around the longitudinal axis, and being disposed generally parallel to the axis of rotation of the vertical shaft, and supporting arms extending radially outwardly from the vertical shaft for supporting the blades. The windmill also includes a first member connected to an upper end of one of the blades and defining a first surface having a leading edge with respect to the direction of movement of the blade and a trailing edge rearward of the leading edge, the leading edge being lower than the trailing edge. The first surface also includes an inside lateral edge and an outer lateral edge spaced radially outwardly from the inside lateral edge, the inside lateral edge being higher than the outer lateral edge. A second member is connected to the lower end of the blade and defines a second surface, the second surface having a leading edge with respect to the direction of movement of the blade and a trailing surface rearward of the second surface leading edge, the second surface leading edge being higher than the trailing edge. The second surface also includes an inside lateral edge and an outer lateral edge spaced radially outwardly from the second surface inside lateral edge, the second surface inside lateral edge being lower than the second surface outside lateral edge.

  14. Electrical generation using a vertical-axis wind turbine

    SciTech Connect (OSTI)

    Clark, R.N.

    1982-12-01

    Traditionally, windmills have been of the propeller or multiblade types, both of which have their rotational axis parallel to the flow of the wind. A vertical-axis wind turbine has its rotational axis perpendicular to the flow of wind and requires no orientation to keep the rotor in the windstream. The vertical-axis wind turbine operates on the same principle as an airfoil and produces lift and drag as any airfoil. A newly designed 100-kW vertical-axis wind turbine has been operated for one year at the USDA Conservation and Production Research Laboratory, Bushland, TX. The turbine has an induction generator and supplies power to a sprinkler irrigation system with excess power being sold to the electric utility. The turbine begins producing power at 5.5 m/s windspeed and reaches its rated output of 100-kW at 15 m/s. The unit has obtained a peak efficiency of 48% at a windspeed of 8 m/s or 81% of theoretical maximum. Using 17 years of windspeed data from the National Weather Service, the annual energy output is estimated at 200,000 kWh. The unit has experienced several operational problems during its initial testing. Guy cables were enlarged to provide greater stiffness to reduce blade stress levels, lightning shorted the main contactor, and the brake system required a complete redesign and modification. The turbine was operational about 60% of the time.

  15. Vertical feed stick wood fuel burning furnace system

    DOE Patents [OSTI]

    Hill, Richard C.

    1984-01-01

    A new and improved stove or furnace for efficient combustion of wood fuel including a vertical feed combustion chamber for receiving and supporting wood fuel in a vertical attitude or stack, a major upper portion of the combustion chamber column comprising a water jacket for coupling to a source of water or heat transfer fluid and for convection circulation of the fluid for confining the locus of wood fuel combustion to the bottom of the vertical gravity feed combustion chamber. A flue gas propagation delay channel extending from the laterally directed draft outlet affords delayed travel time in a high temperature environment to assure substantially complete combustion of the gaseous products of wood burning with forced air as an actively induced draft draws the fuel gas and air mixture laterally through the combustion and high temperature zone. Active sources of forced air and induced draft are included, multiple use and circuit couplings for the recovered heat, and construction features in the refractory material substructure and metal component superstructure.

  16. A new alternative in vertical barrier wall construction

    SciTech Connect (OSTI)

    Rawl, G.F.

    1997-12-31

    A new proprietary vertical barrier wall system has been developed to revolutionize the construction process by eliminating many of the concerns of conventional installation method`s with respect to performance, installation constraints and costs. Vertical barrier walls have been used in the environmental and construction industries for a variety of purposes, usually for cut-off or containment. The typical scenario involves a groundwater contamination problem, in which a vertical barrier wall is utilized to contain or confine the spread of contaminants below the ground surface. Conventional construction techniques have been adequate in many applications, but often fall short of their intended purposes due to physical constraints. In many instances, the economics of these conventional methods have limited the utilization of physical barrier walls. Polywall, the trade name for this new barrier wall technology, was subsequently developed to meet these needs and offer a number of distinct advantages in a variety of scenarios by maximizing confinement and minimizing installation costs. Polywall is constructed from chemically resistant high density polyethylene (HDPE) plastic. It has proven in a half-dozen projects to date to be the most cost-effective and technically sound approach to many containment situations. This paper will cover the development of the technology and will provide a brief synopsis of several installations.

  17. Low profile, high load vertical rolling positioning stage

    DOE Patents [OSTI]

    Shu, Deming; Barraza, Juan

    1996-01-01

    A stage or support platform assembly for use in a synchrotron accurately positions equipment to be used in the beam line of the synchrotron. The support platform assembly includes an outer housing in which is disposed a lifting mechanism having a lifting platform or stage at its upper extremity on which the equipment is mounted. A worm gear assembly is located in the housing and is adapted to raise and lower a lifting shaft that is fixed to the lifting platform by an anti-binding connection. The lifting platform is moved vertically as the lifting shaft is moved vertically. The anti-binding connection prevents the shaft from rotating with respect to the platform, but does permit slight canting of the shaft with respect to the lifting platform so as to eliminate binding and wear due to possible tolerance mismatches. In order to ensure that the lifting mechanism does not move in a horizontal direction as it is moved vertically, at least three linear roller bearing assemblies are arranged around the outer-periphery of the lifting mechanism. One of the linear roller bearing assemblies can be adjusted so that the roller bearings apply a loading force against the lifting mechanism. Alternatively, a cam mechanism can be used to provide such a loading force.

  18. Development of time-domain differential Raman for transient thermal probing of materials

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

    Xu, Shen; Wang, Tianyu; Hurley, David; Yue, Yanan; Wang, Xinwei

    2015-01-01

    A novel transient thermal characterization technology is developed based on the principles of transient optical heating and Raman probing: time-domain differential Raman. It employs a square-wave modulated laser of varying duty cycle to realize controlled heating and transient thermal probing. Very well defined extension of the heating time in each measurement changes the temperature evolution profile and the probed temperature field at ?s resolution. Using this new technique, the transient thermal response of a tipless Si cantilever is investigated along the length direction. A physical model is developed to reconstruct the Raman spectrum considering the temperature evolution, while taking intomoreaccount the temperature dependence of the Raman emission. By fitting the variation of the normalized Raman peak intensity, wavenumber, and peak area against the heating time, the thermal diffusivity is determined as 9.17 10??, 8.14 10??, and 9.51 10?? m/s. These results agree well with the reference value of 8.66 10?? m/s considering the 10% fitting uncertainty. The time-domain differential Raman provides a novel way to introduce transient thermal excitation of materials, probe the thermal response, and measure the thermal diffusivity, all with high accuracy.less

  19. Raman spectra and electron-phonon coupling in disordered graphene with gate-tunable doping

    SciTech Connect (OSTI)

    Childres, Isaac; Jauregui, Luis A.; Chen, Yong P.

    2014-12-21

    We report a Raman spectroscopy study of graphene field-effect transistors with a controlled amount of defects introduced in graphene by exposure to electron-beam irradiation. Raman spectra are taken at T = 8 K over a range of back gate voltages (V{sub g}) for various irradiation dosages (R{sub e}). We study effects in the Raman spectra due to V{sub g}-induced doping and artificially created disorder at various R{sub e}. With moderate disorder (irradiation), the Raman G peak with respect to the graphene carrier density (n{sub FE}) exhibits a minimum in peak frequency and a maximum in peak width near the charge-neutral point (CNP). These trends are similar to those seen in previous works on pristine graphene and have been attributed to a reduction of electron-phonon coupling strength (D) and removal of the Kohn anomaly as the Fermi level moves away from the CNP. We also observe a maximum in I{sub 2D}/I{sub G} and weak maximum in I{sub D}/I{sub G} near the CNP. All the observed dependences of Raman parameters on n{sub FE} weaken at stronger disorder (higher R{sub e}), implying that disorder causes a reduction of D as well. Our findings are valuable for understanding Raman spectra and electron-phonon physics in doped and disordered graphene.

  20. Raman Spectroscopy of DNA Packaging in Individual Human Sperm Cells distinguishes Normal from Abnormal Cells

    SciTech Connect (OSTI)

    Huser, T; Orme, C; Hollars, C; Corzett, M; Balhorn, R

    2009-03-09

    Healthy human males produce sperm cells of which about 25-40% have abnormal head shapes. Increases in the percentage of sperm exhibiting aberrant sperm head morphologies have been correlated with male infertility, and biochemical studies of pooled sperm have suggested that sperm with abnormal shape may contain DNA that has not been properly repackaged by protamine during spermatid development. We have used micro-Raman spectroscopy to obtain Raman spectra from individual human sperm cells and examined how differences in the Raman spectra of sperm chromatin correlate with cell shape. We show that Raman spectra of individual sperm cells contain vibrational marker modes that can be used to assess the efficiency of DNA-packaging for each cell. Raman spectra obtained from sperm cells with normal shape provide evidence that DNA in these sperm is very efficiently packaged. We find, however, that the relative protein content per cell and DNA packaging efficiencies are distributed over a relatively wide range for sperm cells with both normal and abnormal shape. These findings indicate that single cell Raman spectroscopy should be a valuable tool in assessing the quality of sperm cells for in-vitro fertilization.

  1. Development of time-domain differential Raman for transient thermal probing of materials

    SciTech Connect (OSTI)

    Xu, Shen; Wang, Tianyu; Hurley, David; Yue, Yanan; Wang, Xinwei

    2015-01-01

    A novel transient thermal characterization technology is developed based on the principles of transient optical heating and Raman probing: time-domain differential Raman. It employs a square-wave modulated laser of varying duty cycle to realize controlled heating and transient thermal probing. Very well defined extension of the heating time in each measurement changes the temperature evolution profile and the probed temperature field at ?s resolution. Using this new technique, the transient thermal response of a tipless Si cantilever is investigated along the length direction. A physical model is developed to reconstruct the Raman spectrum considering the temperature evolution, while taking into account the temperature dependence of the Raman emission. By fitting the variation of the normalized Raman peak intensity, wavenumber, and peak area against the heating time, the thermal diffusivity is determined as 9.17 10??, 8.14 10??, and 9.51 10?? m/s. These results agree well with the reference value of 8.66 10?? m/s considering the 10% fitting uncertainty. The time-domain differential Raman provides a novel way to introduce transient thermal excitation of materials, probe the thermal response, and measure the thermal diffusivity, all with high accuracy.

  2. Near IR Scanning Angle Total Internal Reflection Raman Spectroscopy at Smooth Gold Films

    SciTech Connect (OSTI)

    McKee, Kristopher; Meyer, Matthew; Smith, Emily

    2012-04-13

    Total internal reflection (TIR) Raman and reflectivity spectra were collected for nonresonant analytes as a function of incident angle at sapphire or sapphire/smooth 50 nm gold interfaces using 785 nm excitation. For both interfaces, the Raman signal as a function of incident angle is well-modeled by the calculated interfacial mean square electric field (MSEF) relative to the incident field times the thickness of the layer being probed in the Raman measurement (D{sub RS}). The Raman scatter was reproducibly enhanced at the interface containing a gold film relative to the sapphire interface by a factor of 4.34.6 for aqueous pyridine or 2.23.7 for neat nitrobenzene, depending on the analyzed vibrational mode. The mechanism for the increased Raman signal is the enhanced MSEF at incident angles where propagating surface plasmons are excited in the metal film. The background from the TIR prism was reduced by 8995% with the addition of the gold film, and the percent relative uncertainty in peak area was reduced from 15 to 1.7% for the 1347 cm1 mode of nitrobenzene. Single monolayers of benzenethiol (S/N = 6.8) and 4-mercaptopyridine (S/N = 16.5) on gold films were measured by TIR Raman spectroscopy with 785 nm excitation (210 mW) without resonant enhancement in 1 min.

  3. Lidar sensing of the atmosphere with gigawatt laser pulses of femtosecond duration

    SciTech Connect (OSTI)

    Bukin, O A; Golik, S S; Il'in, A A; Kulchin, Yu N; Lisitsa, V V; Shmirko, K A; Babii, M Yu; Kolesnikov, A V; Kabanov, A M; Matvienko, G G; Oshlakov, V K

    2014-06-30

    We present the results of sensing of the atmosphere in the condition of a transition 'continent – ocean' zone by means of gigawatt femtosecond pulses of the fundamental and second harmonics of a Ti : sapphire laser. In the regime of multi-frequency sensing (supercontinuum from the fundamental harmonic) the emission lines of the first positive system of the nitrogen molecule B{sup 3}Π{sub g} – A{sup 3}Σ{sub u}{sup +} have been recorded, while the sensing using of the second harmonic have revealed the possibility of detecting the lines of Raman scattering of nitrogen (λ = 441 nm). The intensity ratio of the line of Raman scattering of nitrogen and the line of elastic scattering at the wavelength of λ = 400 nm amounts to 5.6 × 10{sup -4}. (extreme light fields and their applications)

  4. 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.

  5. ARM - Measurement - Aerosol scattering

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

    : Nephelometer PASS : Photoacoustic Soot Spectrometer RL : Raman Lidar TDMA : Tandem Differential Mobility Analyzer Field Campaign Instruments AMT : Aerosol Modeling...

  6. Origin invariance in vibrational resonance Raman optical activity

    SciTech Connect (OSTI)

    Vidal, Luciano N. Cappelli, Chiara; Egidi, Franco; Barone, Vincenzo

    2015-05-07

    A theoretical investigation on the origin dependence of the vibronic polarizabilities, isotropic and anisotropic rotational invariants, and scattering cross sections in Resonance Raman Optical Activity (RROA) spectroscopy is presented. Expressions showing the origin dependence of these polarizabilities were written in the resonance regime using the Franck-Condon (FC) and Herzberg-Teller (HT) approximations for the electronic transition moments. Differently from the far-from-resonance scattering regime, where the origin dependent terms cancel out when the rotational invariants are calculated, RROA spectrum can exhibit some origin dependence even for eigenfunctions of the electronic Hamiltonian. At the FC level, the RROA spectrum is completely origin invariant if the polarizabilities are calculated using a single excited state or for a set of degenerate states. Otherwise, some origin effects can be observed in the spectrum. At the HT level, RROA spectrum is origin dependent even when the polarizabilities are evaluated from a single excited state but the origin effect is expected to be small in this case. Numerical calculations performed for (S)-methyloxirane, (2R,3R)-dimethyloxirane, and (R)-4-F-2-azetidinone at both FC and HT levels using the velocity representation of the electric dipole and quadrupole transition moments confirm the predictions of the theory and show the extent of origin effects and the effectiveness of suggested ways to remove them.

  7. High-pressure study of isoviolanthrone by Raman spectroscopy

    SciTech Connect (OSTI)

    Zhao, Xiao-Miao; Huang, Qiao-Wei; Zhang, Jiang; Zhong, Guo-Hua; Lin, Hai-Qing; Chen, Xiao-Jia

    2014-06-28

    Vibrational properties of isoviolanthrone are investigated by Raman scattering at pressures up to 30.5 GPa and room temperature. A complete characterization of phonon spectra under pressure is given for this material. The onset of a phase transition at 11.0 GPa and the formation of a new phase above 13.8 GPa are identified from both the frequency shifts and the changes in the full width half maxima of the intra- and internal modes. The transition is proposed to result from the changes of intra- and intermolecular bonding. The tendencies of the intensity ratios with pressure are in good agreement with the pressure dependence of the resistance at room temperature, indicating that the phase transition may be an electronic origin. The absence of the changes in the lattice modes indicates that the observed phase transition is probably a result of the structural distortions or reorganizations. The reversible character of the transition upon compression and decompression is determined in the entire pressure region studied.

  8. Measuring depth profiles of residual stress with Raman spectroscopy

    SciTech Connect (OSTI)

    Enloe, W.S.; Sparks, R.G.; Paesler, M.A.

    1988-12-01

    Knowledge of the variation of residual stress is a very important factor in understanding the properties of machined surfaces. The nature of the residual stress can determine a part`s susceptibility to wear deformation, and cracking. Raman spectroscopy is known to be a very useful technique for measuring residual stress in many materials. These measurements are routinely made with a lateral resolution of 1{mu}m and an accuracy of 0.1 kbar. The variation of stress with depth; however, has not received much attention in the past. A novel technique has been developed that allows quantitative measurement of the variation of the residual stress with depth with an accuracy of 10nm in the z direction. Qualitative techniques for determining whether the stress is varying with depth are presented. It is also demonstrated that when the stress is changing over the volume sampled, errors can be introduced if the variation of the stress with depth is ignored. Computer aided data analysis is used to determine the depth dependence of the residual stress.

  9. A compact double-pass Raman backscattering amplifier/compressor

    SciTech Connect (OSTI)

    Ren, J.; Li, S.; Morozov, A.; Suckewer, S.; Yampolsky, N. A.; Malkin, V. M.; Fisch, N. J.

    2008-05-15

    The enhancement of stimulated Raman backscattering (SRBS) amplification was demonstrated by introducing a plasma density gradient along the pump and the seed interaction path and by a novel double-pass design. The energy transfer efficiency was significantly improved to a level of 6.4%. The seed pulse was amplified by a factor of more than 20 000 from the input in a 2 mm long plasma, which also exceeded the intensity of the pump pulse by 2 orders of magnitude. This was accompanied by very effective pulse compression, from 500 fs to 90 fs in the first pass measurements and in the second pass down to approximately 50 fs, as it is indicated by the energy-pulse duration relation. Further improvements to the energy transfer efficiency and the SRBS performance by extending the region of resonance is also discussed where a uniform {approx}4 mm long plasma channel for SRBS was generated by using two subsequent laser pulses in an ethane gas jet.

  10. Sandia Vertical-Axis Wind-Turbine Research Presented at Science...

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

    Vertical-Axis Wind-Turbine Research Presented at Science of Making Torque from Wind ... Twitter Google + Vimeo GovDelivery SlideShare Sandia Vertical-Axis Wind-Turbine Research ...

  11. Sandia and Partners Complete Phase I of a Vertical-Axis Deep...

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

    I of a Vertical-Axis Deep-Water Offshore Turbine Study - Sandia Energy Energy Search Icon ... Sandia and Partners Complete Phase I of a Vertical-Axis Deep-Water Offshore Turbine Study ...

  12. Hanford Disposal Facility Expands Vertically to Make Room for More Waste |

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

    Department of Energy Disposal Facility Expands Vertically to Make Room for More Waste Hanford Disposal Facility Expands Vertically to Make Room for More Waste February 11, 2016 - 12:25pm Addthis This photo illustration of the conceptual view shows the vertical expansion of the Environmental Restoration Disposal Facility. The large area on the right includes the uppermost surface of the vertical expansion, which will be shaped to form a crown and will be covered with a 2 percent grade and

  13. Vertical-axis wind turbines -- The current status of an old technology

    SciTech Connect (OSTI)

    Berg, D.E.

    1996-12-31

    Vertical-axis wind turbine technology is not well understood, even though the earliest wind machines rotated about a vertical axis. The operating environment of a vertical-axis wind turbine is quite complex, but detailed analysis capabilities have been developed and verified over the last 30 years. Although vertical-axis technology has not been widely commercialized, it exhibits both advantages and disadvantages compared to horizontal-axis technology, and in some applications, it appears to offer significant advantages.

  14. Vertical Distribution of Contamination in Ground Water at the Tuba City,

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

    Arizona, Site | Department of Energy Vertical Distribution of Contamination in Ground Water at the Tuba City, Arizona, Site Vertical Distribution of Contamination in Ground Water at the Tuba City, Arizona, Site Vertical Distribution of Contamination in Ground Water at the Tuba City, Arizona, Site Vertical Distribution of Contamination in Ground Water at the Tuba City, Arizona, Site (7.2 MB) More Documents & Publications Diffusion Multilayer Sampling of Ground Water in Five Wells at the

  15. 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.

  16. SGP and TWP (Manus) Ice Cloud Vertical Velocities

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

    Kalesse, Heike

    Daily netcdf-files of ice-cloud dynamics observed at the ARM sites at SGP (Jan1997-Dec2010) and Manus (Jul1999-Dec2010). The files include variables at different time resolution (10s, 20min, 1hr). Profiles of radar reflectivity factor (dbz), Doppler velocity (vel) as well as retrieved vertical air motion (V_air) and reflectivity-weighted particle terminal fall velocity (V_ter) are given at 10s, 20min and 1hr resolution. Retrieved V_air and V_ter follow radar notation, so positive values indicate downward motion. Lower level clouds are removed, however a multi-layer flag is included.

  17. Injector Cavities Fabrication, Vertical Test Performance and Primary Cryomodule Design

    SciTech Connect (OSTI)

    Wang, Haipeng; Cheng, Guangfeng; Clemens, William; Davis, G; Henry, James; Macha, Kurt; Overton, Roland

    2015-09-01

    After the electromagnetic design * and the mechanical design ** of a β=0.6, 2-cell elliptical SRF cavity, the cavity has been fabricated. Then both 2-cell and 7-cell cavities have been bench tuned to the target values of frequency, coupling external Q and field flatness. After buffer chemistry polishing (BCP) and high pressure rinses (HPR), Vertical 2K cavity test results have been satisfied the specifications and ready for the string assembly. We will report the cavity performance including Lorenz Force Detuning (LFD) and Higher Order Modes (HOM) damping data. Its integration with cavity tuners to the cryomodule design will be reported.

  18. SGP and TWP (Manus) Ice Cloud Vertical Velocities

    SciTech Connect (OSTI)

    Kalesse, Heike

    2013-06-27

    Daily netcdf-files of ice-cloud dynamics observed at the ARM sites at SGP (Jan1997-Dec2010) and Manus (Jul1999-Dec2010). The files include variables at different time resolution (10s, 20min, 1hr). Profiles of radar reflectivity factor (dbz), Doppler velocity (vel) as well as retrieved vertical air motion (V_air) and reflectivity-weighted particle terminal fall velocity (V_ter) are given at 10s, 20min and 1hr resolution. Retrieved V_air and V_ter follow radar notation, so positive values indicate downward motion. Lower level clouds are removed, however a multi-layer flag is included.

  19. VERTICAL RELAXATION OF A MOONLET PROPELLER IN SATURN'S A RING

    SciTech Connect (OSTI)

    Hoffmann, H.; Seiss, M.; Spahn, F. [Institute of Physics and Astronomy, University of Potsdam, D-14476 Golm (Germany)

    2013-03-01

    Two images, taken by the Cassini spacecraft near Saturn's equinox in 2009 August, show the Earhart propeller casting a 350 km long shadow, offering the opportunity to watch how the ring height, excited by the propeller moonlet, relaxes to an equilibrium state. From the shape of the shadow cast and a model of the azimuthal propeller height relaxation, we determine the exponential cooling constant of this process to be {lambda} = 0.07 {+-} 0.02 km{sup -1}, and thereby determine the collision frequency of the ring particles in the vertically excited region of the propeller to be {omega}{sub c}/{Omega} = 0.9 {+-} 0.2.

  20. Torque ripple in a Darrieus, vertical axis wind turbine

    SciTech Connect (OSTI)

    Reuter, R.C. Jr.

    1980-09-01

    Interaction between a steady wind and a rotating, Darrieus, vertical axis wind turbine produces time periodic aerodynamic loads which cause time dependent torque variations, referred to as torque ripple, to occur in the mechanical link between the turbine and the electrical generator. There is concern for the effect of torque ripple upon fatigue life of drive train components and upon power quality. An analytical solution characterizing the phenomenon of torque ripple has been obtained which is based upon a Fourier expansion of the time dependent features of the problem. Numerical results for torque ripple, some experimental data, determination of acceptable levels and methods of controlling it, are presented and discussed.

  1. Economic analysis of vertical wells for coalbed methane recovery

    SciTech Connect (OSTI)

    Not Available

    1981-04-01

    Previous economic studies of the recovery and utilization of methane from coalbeds using vertical wells were based on drainage in advance of mining where a single seam is drained with well spacing designed for rapid predrainage. This study extends the earlier work and shows that methane recovery costs can be reduced significantly by increasing well spacing and draining multiple coalbeds. A favorable return on investment can be realized in many geologic settings using this method. Sensitivity of recovery economics to certain development costs and parametric variations are also examined as are the economics of three methane utilization options.

  2. Numerical simulation model for vertical flow in geothermal wells

    SciTech Connect (OSTI)

    Tachimori, M.

    1982-01-01

    A numerical simulation model for vertical flow in geothermal wells is presented. The model consists of equations for the conservation of mass, momentum, and energy, for thermodynamic state of water, for friction losses, for slip velocity relations, and of the criteria for various flow regimes. A new set of correlations and criteria is presented for two-phase flow to improve the accuracy of predictions; bubbly flow - Griffith and Wallis correlation, slug flow - Nicklin et al. one, annular-mist flow - Inoue and Aoki and modified by the author. The simulation method was verified by data from actual wells.

  3. Probing Xylan-Specific Raman Bands for Label-Free Imaging Xylan in Plant Cell Wall

    SciTech Connect (OSTI)

    Zeng, Yining; Yarbrough, John M.; Mittal, Ashutosh; Tucker, Melvin P.; Vinzant, Todd; Himmel, Michael E.

    2015-06-15

    Xylan constitutes a significant portion of biomass (e.g. 22% in corn stover used in this study). Xylan is also an important source of carbohydrates, besides cellulose, for renewable and sustainable energy applications. Currently used method for the localization of xylan in biomass is to use fluorescence confocal microscope to image the fluorescent dye labeled monoclonal antibody that specifically binds to xylan. With the rapid adoption of the Raman-based label-free chemical imaging techniques in biology, identifying Raman bands that are unique to xylan would be critical for the implementation of the above label-free techniques for in situ xylan imaging. Unlike lignin and cellulose that have long be assigned fingerprint Raman bands, specific Raman bands for xylan remain unclear. The major challenge is the cellulose in plant cell wall, which has chemical units highly similar to that of xylan. Here we report using xylanase to specifically remove xylan from feedstock. Under various degree of xylan removal, with minimum impact to other major cell wall components, i.e. lignin and cellulose, we have identified Raman bands that could be further tested for chemical imaging of xylan in biomass in situ.

  4. Light trapping in thin-film solar cells measured by Raman spectroscopy

    SciTech Connect (OSTI)

    Ledinský, M.; Moulin, E.; Bugnon, G.; Meillaud, F.; Ballif, C.; Ganzerová, K.; Vetushka, A.; Fejfar, A.

    2014-09-15

    In this study, Raman spectroscopy is used as a tool to determine the light-trapping capability of textured ZnO front electrodes implemented in microcrystalline silicon (μc-Si:H) solar cells. Microcrystalline silicon films deposited on superstrates of various roughnesses are characterized by Raman micro-spectroscopy at excitation wavelengths of 442 nm, 514 nm, 633 nm, and 785 nm, respectively. The way to measure quantitatively and with a high level of reproducibility the Raman intensity is described in details. By varying the superstrate texture and with it the light trapping in the μc-Si:H absorber layer, we find significant differences in the absolute Raman intensity measured in the near infrared wavelength region (where light trapping is relevant). A good agreement between the absolute Raman intensity and the external quantum efficiency of the μc-Si:H solar cells is obtained, demonstrating the validity of the introduced method. Applications to thin-film solar cells, in general, and other optoelectronic devices are discussed.

  5. The effects of machine parameters on residual stress determined using micro-Raman spectroscopy

    SciTech Connect (OSTI)

    Sparks, R.G.; Enloe, W.S.; Paesler, M.A.

    1988-12-01

    The effects of machine parameters on residual stresses in single point diamond turned silicon and germanium have been investigated using micro-Raman spectroscopy. Residual stresses were sampled across ductile feed cuts in < 100 > silicon and germanium which were single point diamond turned using a variety of feed rates, rake angles and clearance angles. High spatial resolution micro-Raman spectra (1{mu}m spot) were obtained in regions of ductile cutting where no visible surface damage was present. The use of both 514-5nm and 488.0nm excitation wavelengths, by virtue of their differing characteristic penetration depths in the materials, allowed determinations of stress profiles as a function of depth into the sample. Previous discussions have demonstrated that such Raman spectra will exhibit asymmetrically broadened peaks which are characteristic of the superposition of a continuum of Raman scatterers from the various depths probed. Depth profiles of residual stress were obtained using computer deconvolution of the resulting asymmetrically broadened raman spectra.

  6. Raman and structural characterization of LuAlO{sub 3}

    SciTech Connect (OSTI)

    Casu, Alberto; Ricci, Pier Carlo

    2011-11-15

    The structural and vibrational properties of lutetium orthoaluminate perovskite (LuAlO{sub 3}) were investigated by means of Raman spectroscopy and EXAFS measurements. The analysis of Raman spectra taken in four different polarized configurations along the principal axes at 20 K and room temperature conditions permits to assign the principal vibrational modes in LuAP single crystals and to confirm the belonging to the D{sub 2h}{sup 16} space group. EXAFS measurements were performed at room temperature in order to obtain local structural informations on the first and next nearest neighbors around lutetium absorptions sites. Unit cell parameters and bond lengths were determined by the analysis of the EXAFS spectroscopy at the L{sub 3} absorption edge of lutetium. The informations thus gathered on this compound can offer a useful addition in the framework of a full structural characterization of LuAlO{sub 3}. - Graphical abstract: Raman active mode in LuAP crystal. Highlights: > Structural characterization of LuAlO{sub 3} is obtained by Raman and EXAFS spectroscopies. > Vibrational modes, temperature-dependent variations studied by Raman spectroscopy. > Cell parameters and local characterization obtained by EXAFS spectroscopy.

  7. Electromagnetic confinement for vertical casting or containing molten metal

    DOE Patents [OSTI]

    Lari, Robert J.; Praeg, Walter F.; Turner, Larry R.

    1991-01-01

    An apparatus and method adapted to confine a molten metal to a region by means of an alternating electromagnetic field. As adapted for use in the present invention, the alternating electromagnetic field given by B.sub.y =(2.mu..sub.o .rho.gy).sup.1/2 (where B.sub.y is the vertical component of the magnetic field generated by the magnet at the boundary of the region; y is the distance measured downward form the top of the region, .rho. is the metal density, g is the acceleration of gravity and .mu..sub.o is the permeability of free space) induces eddy currents in the molten metal which interact with the magnetic field to retain the molten metal with a vertical boudnary. As applied to an apparatus for the continuous casting of metal sheets or rods, metal in liquid form can be continuously introduced into the region defined by the magnetic field, solidified and conveyed away from the magnetic field in solid form in a continuous process.

  8. Vertical distribution of structural components in corn stover

    SciTech Connect (OSTI)

    Johnson, Jane M. F.; Karlen, Douglas L.; Gresham, Garold L.; Cantrell, Keri B.; Archer, David W.; Wienhold, Brian J.; Varvel, Gary E.; Laird, David A.; Baker, John; Ochsner, Tyson E.; Novak, Jeff M.; Halvorson, Ardell D.; Arriaga, Francisco; Lightle, David T.; Hoover, Amber; Emerson, Rachel; Barbour, Nancy W.

    2014-11-17

    In the United States, corn (Zea mays L.) stover has been targeted for second generation fuel production and other bio-products. Our objective was to characterize sugar and structural composition as a function of vertical distribution of corn stover (leaves and stalk) that was sampled at physiological maturity and about three weeks later from multiple USA locations. A small subset of samples was assessed for thermochemical composition. Concentrations of lignin, glucan, and xylan were about 10% greater at grain harvest than at physiological maturity, but harvestable biomass was about 25% less due to stalk breakage. Gross heating density above the ear averaged 16.3 ± 0.40 MJ kg⁻¹, but with an alkalinity measure of 0.83 g MJ⁻¹, slagging is likely to occur during gasification. Assuming a stover harvest height of 10 cm, the estimated ethanol yield would be >2500 L ha⁻¹, but it would be only 1000 L ha⁻¹ if stover harvest was restricted to the material from above the primary ear. Vertical composition of corn stover is relatively uniform; thus, decision on cutting height may be driven by agronomic, economic and environmental considerations.

  9. FFTF vertical sodium storage tank preliminary thermal analysis

    SciTech Connect (OSTI)

    Irwin, J.J.

    1995-02-21

    In the FFTF Shutdown Program, sodium from the primary and secondary heat transport loops, Interim Decay Storage (IDS), and Fuel Storage Facility (FSF) will be transferred to four large storage tanks for temporary storage. Three of the storage tanks will be cylindrical vertical tanks having a diameter of 28 feet, height of 22 feet and fabricated from carbon steel. The fourth tank is a horizontal cylindrical tank but is not the subject of this report. The storage tanks will be located near the FFTF in the 400 Area and rest on a steel-lined concrete slab in an enclosed building. The purpose of this work is to document the thermal analyses that were performed to ensure that the vertical FFTF sodium storage tank design is feasible from a thermal standpoint. The key criterion for this analysis is the time to heat up the storage tank containing frozen sodium at ambient temperature to 400 F. Normal operating conditions include an ambient temperature range of 32 F to 120 F. A key parameter in the evaluation of the sodium storage tank is the type of insulation. The baseline case assumed six inches of calcium silicate insulation. An alternate case assumed refractory fiber (Cerablanket) insulation also with a thickness of six inches. Both cases assumed a total electrical trace heat load of 60 kW, with 24 kW evenly distributed on the bottom head and 36 kW evenly distributed on the tank side wall.

  10. Vertical dispersion of inertial waves in the upper ocean

    SciTech Connect (OSTI)

    Rubenstein, D.M.

    1983-05-20

    A linear model of the vertical dispersion of near-inertial waves is developed. A porosity distribution near the bottom of the computational domain minimizes bottom reflections and simulates an ocean of the infinite depth. The model is used to show that the vertical dispersion of near-inertial waves in the upper ocean may, under certain conditions, contribute significanlty to the observed rapid decay of inertial oscillations in the surface layer. The kinetic energy of inertial oscillations at mid-latitudes decays with an e folding time scale of 10 days or less, when the parameter lambda(km)/N(cph)d(m) is less than or of the order of unity, where lambda is the wavelength of the wind-generated near-inertial waves, N is the Vaeisaelae frequency in the upper pycnocline, and d is the surface layer thickness. At the top of the pycnocline the model predicts a velocity maximum, which develops as energy propagates downward, out of the surface layer. However, when the upper pycnocline is sufficiently peaked, a resonant frequency interference effect is predicted. This effect modulates the dissipation of surface layer inertial oscillations, and their magnitude after a storm need not decay monotonically. We also make qualitative comparisons with deep-ocean current meter observations taken during the Mixed Layer Experiment (MILE) and with shallow water (105 m) observations taken in the Baltic Sea.

  11. Vertical distribution of structural components in corn stover

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

    Johnson, Jane M. F.; Karlen, Douglas L.; Gresham, Garold L.; Cantrell, Keri B.; Archer, David W.; Wienhold, Brian J.; Varvel, Gary E.; Laird, David A.; Baker, John; Ochsner, Tyson E.; et al

    2014-11-17

    In the United States, corn (Zea mays L.) stover has been targeted for second generation fuel production and other bio-products. Our objective was to characterize sugar and structural composition as a function of vertical distribution of corn stover (leaves and stalk) that was sampled at physiological maturity and about three weeks later from multiple USA locations. A small subset of samples was assessed for thermochemical composition. Concentrations of lignin, glucan, and xylan were about 10% greater at grain harvest than at physiological maturity, but harvestable biomass was about 25% less due to stalk breakage. Gross heating density above the earmore » averaged 16.3 ± 0.40 MJ kg⁻¹, but with an alkalinity measure of 0.83 g MJ⁻¹, slagging is likely to occur during gasification. Assuming a stover harvest height of 10 cm, the estimated ethanol yield would be >2500 L ha⁻¹, but it would be only 1000 L ha⁻¹ if stover harvest was restricted to the material from above the primary ear. Vertical composition of corn stover is relatively uniform; thus, decision on cutting height may be driven by agronomic, economic and environmental considerations.« less

  12. Control system for a vertical-axis windmill

    DOE Patents [OSTI]

    Brulle, R.V.

    1981-09-03

    A vertical-axis windmill having a rotating structure is provided with a series of articulated vertical blades whose positions are controlled to maintain a constant RPM for the rotating structure, when wind speed is sufficient. A microprocessor controller is used to process information on wind speed, wind direction and RPM of the rotating structure to develop an electrical signal for establishing blade position. The preferred embodiment of the invention, when connected to a utility grid, is designed to generate 40 kilowatts of power when exposed to a 20 mile per hour wind. The control system for the windmill includes electrical blade actuators that modulate the blades of the rotating structure. Blade modulation controls the blade angle of attack, which in turn controls the RPM of the rotor. In the preferred embodiment, the microprocessor controller provides the operation logic and control functions. A wind speed sensor provides inputs to start or stop the windmill, and a wind direction sensor is used to keep the blade flip region at 90 and 270/sup 0/ to the wind. The control system is designed to maintain constant rotor RPM when wind speed is between 10 and 40 miles per hour.

  13. Vertical distribution of structural components in corn stover

    SciTech Connect (OSTI)

    Jane M. F. Johnson; Douglas L. Karlen; Garold L. Gresham; Keri B. Cantrell; David W. Archer; Brian J. Wienhold; Gary E. Varvel; David A. Laird; John Baker; Tyson E. Ochsner; Jeff M. Novak; Ardell D. Halvorson; Francisco Arriaga; David T. Lightle; Amber Hoover; Rachel Emerson; Nancy W. Barbour

    2014-11-01

    In the United States, corn (Zea mays L.) stover has been targeted for second generation fuel production and other bio-products. Our objective was to characterize sugar and structural composition as a function of vertical distribution of corn stover (leaves and stalk) that was sampled at physiological maturity and about three weeks later from multiple USA locations. A small subset of samples was assessed for thermochemical composition. Concentrations of lignin, glucan, and xylan were about 10% greater at grain harvest than at physiological maturity, but harvestable biomass was about 25% less due to stalk breakage. Gross heating density above the ear averaged 16.3 0.40 MJ kg?, but with an alkalinity measure of 0.83 g MJ?, slagging is likely to occur during gasification. Assuming a stover harvest height of 10 cm, the estimated ethanol yield would be >2500 L ha?, but it would be only 1000 L ha? if stover harvest was restricted to the material from above the primary ear. Vertical composition of corn stover is relatively uniform; thus, decision on cutting height may be driven by agronomic, economic and environmental considerations.

  14. Thrust stand for vertically oriented electric propulsion performance evaluation

    SciTech Connect (OSTI)

    Moeller, Trevor; Polzin, Kurt A.

    2010-11-15

    A variation of a hanging pendulum thrust stand capable of measuring the performance of an electric thruster operating in the vertical orientation is presented. The vertical orientation of the thruster dictates that the thruster must be horizontally offset from the pendulum pivot arm, necessitating the use of a counterweight system to provide a neutrally stable system. Motion of the pendulum arm is transferred through a balance mechanism to a secondary arm on which deflection is measured. A noncontact light-based transducer is used to measure displacement of the secondary beam. The members experience very little friction, rotating on twisting torsional pivots with oscillatory motion attenuated by a passive, eddy-current damper. Displacement is calibrated using an in situ thrust calibration system. Thermal management and self-leveling systems are incorporated to mitigate thermal and mechanical drifts. Gravitational force and torsional spring constants associated with flexure pivots provide restoring moments. An analysis of the design indicates that the thrust measurement range spans roughly four decades, with the stand capable of measuring thrust up to 12 N for a 200 kg thruster and up to approximately 800 mN for a 10 kg thruster. Data obtained from calibration tests performed using a 26.8 lbm simulated thruster indicated a resolution of 1 mN on 100 mN level thrusts, while those tests conducted on a 200 lbm thruster yielded a resolution of roughly 2.5 mN at thrust levels of 0.5 N and greater.

  15. Vertical feed stick wood fuel burning furnace system

    DOE Patents [OSTI]

    Hill, Richard C.

    1982-01-01

    A stove or furnace for efficient combustion of wood fuel includes a vertical feed combustion chamber (15) for receiving and supporting wood fuel in a vertical attitude or stack. A major upper portion of the combustion chamber column comprises a water jacket (14) for coupling to a source of water or heat transfer fluid for convection circulation of the fluid. The locus (31) of wood fuel combustion is thereby confined to the refractory base of the combustion chamber. A flue gas propagation delay channel (34) extending laterally from the base of the chamber affords delayed travel time in a high temperature refractory environment sufficient to assure substantially complete combustion of the gaseous products of wood burning with forced air prior to extraction of heat in heat exchanger (16). Induced draft draws the fuel gas and air mixture laterally through the combustion chamber and refractory high temperature zone to the heat exchanger and flue. Also included are active sources of forced air and induced draft, multiple circuit couplings for the recovered heat, and construction features in the refractory material substructure and metal component superstructure.

  16. Feshbach-resonant Raman photoassociation in a Bose-Einstein condensate

    SciTech Connect (OSTI)

    Mackie, Matt; Phou, Pierre; Shinn, Mannix; Boyce, Heather; Katz, Lev

    2011-10-15

    We model the formation of stable heteronuclear molecules via pulsed Raman photoassociation of a two-component Bose-Einstein condensate near a strong Feshbach resonance, for both counterintuitive and intuitive pulse sequencing. Compared to lasers alone, weak Raman photoassociation is enhanced by as much as a factor of ten (five) for a counterintuitive (intuitive) pulse sequence, whereas strong Raman photoassociation is barely enhanced at all--regardless of pulse sequence. Stronger intra-atom, molecule, or atom-molecule collisions lead to an expected decrease in conversion efficiency, but stronger ambient inter-atom collisions lead to an unexpected increase in the efficiency of stable molecule production. Numerical results agree reasonably with an analytical approximation.

  17. Fiber-optic apparatus and method for measurement of luminescence and raman scattering

    DOE Patents [OSTI]

    Myrick, Michael L.; Angel, Stanley M.

    1993-01-01

    A dual fiber forward scattering optrode for Raman spectroscopy with the remote ends of the fibers in opposed, spaced relationship to each other to form a analyte sampling space therebetween and the method of measuring Raman spectra utilizing same. One optical fiber is for sending an exciting signal to the remote sampling space and, at its remote end, has a collimating microlens and an optical filter for filtering out background emissions generated in the fiber. The other optical fiber is for collecting the Raman scattering signal at the remote sampling space and, at its remote end, has a collimating microlens and an optical filter to prevent the exciting signal from the exciting fiber from entering the collection fiber and to thereby prevent the generation of background emissions in the collecting fiber.

  18. Fiber-optic apparatus and method for measurement of luminescence and Raman scattering

    DOE Patents [OSTI]

    Myrick, M.L.; Angel, S.M.

    1993-03-16

    A dual fiber forward scattering optrode for Raman spectroscopy with the remote ends of the fibers in opposed, spaced relationship to each other to form a analyte sampling space therebetween and the method of measuring Raman spectra utilizing same are described. One optical fiber is for sending an exciting signal to the remote sampling space and, at its remote end, has a collimating microlens and an optical filter for filtering out background emissions generated in the fiber. The other optical fiber is for collecting the Raman scattering signal at the remote sampling space and, at its remote end, has a collimating microlens and an optical filter to prevent the exciting signal from the exciting fiber from entering the collection fiber and to thereby prevent the generation of background emissions in the collecting fiber.

  19. Isotopic hydrogen analysis via conventional and surface-enhanced fiber optic Raman spectroscopy

    SciTech Connect (OSTI)

    LASCOLA, ROBERT

    2004-09-23

    This report describes laboratory development and process plant applications of Raman spectroscopy for detection of hydrogen isotopes in the Tritium Facilities at the Savannah River Site (SRS), a U.S. Department of Energy complex. Raman spectroscopy provides a lower-cost, in situ alternative to mass spectrometry techniques currently employed at SRS. Using conventional Raman and fiber optics, we have measured, in the production facility glove boxes, process mixtures of protium and deuterium at various compositions and total pressures ranging from 1000-4000 torr, with detection limits ranging from 1-2 percent for as low as 3-second integration times. We are currently investigating fabrication techniques for SERS surfaces in order to measure trace (0.01-0.1 percent) amounts of one isotope in the presence of the other. These efforts have concentrated on surfaces containing palladium, which promotes hydrogen dissociation and forms metal hydride bonds, essentially providing a chemical enhancement mechanism.

  20. Raman scattering investigation of large positive magnetoresistance material WTe{sub 2}

    SciTech Connect (OSTI)

    Kong, W.-D.; Wu, S.-F.; Lian, C.-S.; Wang, J.-T.; Yang, C.-L.; Shi, Y.-G.; Richard, P. Ding, H.

    2015-02-23

    We have performed polarized Raman scattering measurements on WTe{sub 2}, for which an extremely large positive magnetoresistance has been reported recently. We observe 5 A{sub 1} phonon modes and 2 A{sub 2} phonon modes out of 33 Raman active modes, with frequencies in good accordance with first-principles calculations. The angular dependence of the intensity of the peaks observed is consistent with the Raman tensors of the C{sub 2v} point group symmetry attributed to WTe{sub 2}. Although the phonon spectra suggest neither strong electron-phonon nor spin-phonon coupling, the intensity of the A{sub 1} phonon mode at 160.6 cm{sup −1} shows an unconventional decrease with temperature decreasing, for which the origin remains unclear.