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1

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

NLE Websites -- All DOE Office Websites (Extended Search)

0 0 Raman Lidar Profiles-Temperature (RLPROFTEMP) Value-Added Product RK Newsom C Sivaraman SA McFarlane October 2012 DISCLAIMER This report was prepared as an account of work sponsored by the U.S. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or

2

Raman Lidar (RL) Handbook  

SciTech Connect

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.

Newsom, RK

2009-03-01T23:59:59.000Z

3

Raman lidar and MPL Measurements during ALIVE  

NLE Websites -- All DOE Office Websites (Extended Search)

Raman lidar and MPL Measurements during ALIVE 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 during the May 2003 Aerosol IOP indicated that the sensitivity of the lidar was significantly lower than when the lidar was initially deployed. This decrease in sensitivity contributed to a significant high bias of the Raman lidar aerosol extinction measurements in relation to airborne Sun

4

Raman lidar/AERI PBL Height Product  

DOE Data Explorer (OSTI)

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.

Ferrare, Richard

5

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

NLE Websites -- All DOE Office Websites (Extended Search)

modifications reduced but could not eliminate these adverse effects. The Raman lidar water vapor (aerosol extinction) measurements produced by these modified algorithms were,...

6

Long-Term Evaluation of Temperature Profiles Measured by an Operational Raman Lidar  

Science Journals Connector (OSTI)

This study investigates the accuracy and calibration stability of temperature profiles derived from an operational Raman lidar over a 2-yr period from 1 January 2009 to 31 December 2010. The lidar, which uses the rotational Raman technique for ...

Rob K. Newsom; David D. Turner; John E. M. Goldsmith

2013-08-01T23:59:59.000Z

7

Ozone Measurements at Geesthacht (53.4° N, 10.4° E) with an Advanced Raman Lidar  

Science Journals Connector (OSTI)

An advanced Raman lidar, which measures ozone, water vapor, aerosol backscatter, and extinction profiles simoultaneously and independently, has been in routine operation at Geesthacht since February 1995. Results...

Marcus Seiwazi; Jens Reichardt…

1997-01-01T23:59:59.000Z

8

Raman lidar profiling of water vapor and aerosols over the ARM SGP Site  

SciTech Connect

The authors have developed and implemented automated algorithms to retrieve profiles of water vapor mixing ratio, aerosol backscattering, and aerosol extinction from Southern Great Plains (SGP) Cloud and Radiation Testbed (CART) Raman Lidar data acquired during both daytime and nighttime operations. The Raman lidar sytem is unique in that it is turnkey, automated system designed for unattended, around-the-clock profiling of water vapor and aerosols. These Raman lidar profiles are important for determining the clear-sky radiative flux, as well as for validating the retrieval algorithms associated with satellite sensors. Accurate, high spatial and temporal resolution profiles of water vapor are also required for assimilation into mesoscale models to improve weather forecasts. The authors have also developed and implemented routines to simultaneously retrieve profiles of relative humidity. These routines utilize the water vapor mixing ratio profiles derived from the Raman lidar measurements together with temperature profiles derived from a physical retrieval algorithm that uses data from a collocated Atmospheric Emitted Radiance Interferometer (AERI) and the Geostationary Operational Environmental Satellite (GOES). These aerosol and water vapor profiles (Raman lidar) and temperature profiles (AERI+GOES) have been combined into a single product that takes advantage of both active and passive remote sensors to characterize the clear sky atmospheric state above the CART site.

Ferrare, R.A.

2000-01-09T23:59:59.000Z

9

RAMAN LIDAR PROFILING OF WATER VAPOR AND AEROSOLS OVER THE ARM SGP SITE.  

SciTech Connect

We have developed and implemented automated algorithms to retrieve profiles of water vapor mixing ratio, aerosol backscattering, and aerosol extinction from Southern Great Plains (SGP) Cloud and Radiation Testbed (CART) Raman Lidar data acquired during both daytime and nighttime operations. This Raman lidar system is unique in that it is turnkey, automated system designed for unattended, around-the-clock profiling of water vapor and aerosols (Goldsmith et al., 1998). These Raman lidar profiles are important for determining the clear-sky radiative flux, as well as for validating the retrieval algorithms associated with satellite sensors. Accurate, high spatial and temporal resolution profiles of water vapor are also required for assimilation into mesoscale models to improve weather forecasts. We have also developed and implemented routines to simultaneously retrieve profiles of relative humidity. These routines utilize the water vapor mixing ratio profiles derived from the Raman lidar measurements together with temperature profiles derived from a physical retrieval algorithm that uses data from a collocated Atmospheric Emitted Radiance Interferometer (AERI) and the Geostationary Operational Environmental Satellite (GOES) (Feltz et al., 1998; Turner et al., 1999). These aerosol and water vapor profiles (Raman lidar) and temperature profiles (AERI+GOES) have been combined into a single product that takes advantage of both active and passive remote sensors to characterize the clear sky atmospheric state above the CART site.

FERRARE,R.A.

2000-01-09T23:59:59.000Z

10

Towards quantifying mesoscale flows in the troposphere using Raman lidar and sondes  

SciTech Connect

Water vapor plays an important role in the energetics of the boundary layer processes which in turn play a key role in regulating regional and global climate. It plays a primary role in Earth`s hydrological cycle, in radiation balance as a direct absorber of infrared radiation, and in atmospheric circulation as a latent heat energy source as well as in determining cloud development and atmospheric stability. Water vapor concentration, expressed as a mass mixing ratio, is conserved in all meteorological processes except condensation and evaporation. This property makes it an ideal choice for studying many of the atmosphere`s dynamic features. Raman scattering measurements from lidar also allow retrieval of water vapor mixing ratio profiles at high temporal and vertical resolution. Raman lidars sense water vapor to altitudes not achievable with towers and surface systems, sample the atmosphere at much higher temporal resolution than radiosondes or satellites, and do not require strong vertical gradients or turbulent fluctuations in temperature that is required by acoustic sounders and radars. Analysis of highly resolved water vapor profiles are used here to characterize two important mesoscale flows: thunderstorm outflows and a cold front passage.

Demoz, B.; Evans, K. [Univ. of Maryland Baltimore County, Baltimore, MD (United States); Starr, D. [NASA, Greenbelt, MD (United States). Goddard Space Flight Center] [and others

1998-03-01T23:59:59.000Z

11

Spaceborne profiling of atmospheric temperature and particle extinction with pure rotational Raman lidar and of relative humidity in combination with differential absorption lidar: performance simulations  

SciTech Connect

The performance of a spaceborne temperature lidar based on the pure rotational Raman (RR) technique in the UV has been simulated. Results show that such a system deployed onboard a low-Earth-orbit satellite would provide global-scale clear-sky temperature measurements in the troposphere and lower stratosphere with precisions that satisfy World Meteorological Organization (WMO) threshold observational requirements for numerical weather prediction and climate research applications. Furthermore, nighttime temperature measurements would still be within the WMO threshold observational requirements in the presence of several cloud structures. The performance of aerosol extinction measurements from space, which can be carried out simultaneously with temperature measurements by RR lidar, is also assessed. Furthermore, we discuss simulations of relative humidity measurements from space obtained from RR temperature measurements and water-vapor data measured with the differential absorption lidar (DIAL) technique.

Di Girolamo, Paolo; Behrendt, Andreas; Wulfmeyer, Volker

2006-04-10T23:59:59.000Z

12

Posters Scanning Raman Lidar Measurements of Atmospheric Water Vapor and Aerosols  

NLE Websites -- All DOE Office Websites (Extended Search)

5 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 circulation models (GCMs) which are used to study climate change. Meeting this objective requires detailed measurements of both water vapor and aerosols since these atmospheric constituents affect the radiation balance directly, through scattering and absorption of solar and

13

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

SciTech Connect

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.

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

2013-08-27T23:59:59.000Z

14

DOE/SC-ARM/TR-100 Raman Lidar Profiles Best Estimate Value-Added Product Technical Report  

NLE Websites -- All DOE Office Websites (Extended Search)

0 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. Government. Neither the United States nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not necessarily constitute or imply its endorsement, recommendation, or favoring by the U.S. Government or any agency thereof. The views and

15

E-Print Network 3.0 - aerosol lidar profilometer Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

CLASIC Summary: Lidar RH Changes in aerosol properties and RH near clouds Airborne NASA LaRC HSRL, ARM SGP ground... ) RamanLidar RelativeHumidityRamanLidar Aerosol Extensive...

16

Raman Lidar Receives Improvements  

NLE Websites -- All DOE Office Websites (Extended Search)

central facility is receiving upgrades to its environmental controls. This ground-based remote sensing instrument uses a laser to measure vertical profiles of water vapor mixing...

17

Raman-shifted KrF laser radiation with low amplified spontaneous emission for a rotational Raman daytime-temperature lidar  

SciTech Connect

Various configurations of a tunable two-stage KrF laser have been investigated for providing powerful laser pulses with very low amplified spontaneous emission (ASE). The lowest fraction (0.00017%) of ASE was attained with a single-pass amplifier and a phase-conjugate Brillouin mirror. The most suitable application envisaged for the laser source, i.e., remote daytime-temperature measurement by means of rotational Raman scattering, is a dedicated oscillator--amplifier configuration with an ASE of 0.005% at an output of 300 mJ. The very low values of ASE were measured with the aid of a thallium atomic-vapor filter.

Luckow, F.; Voss, E.; Zeyn, J.; Lahmann, W.; Weitkamp, C.; Michaelis, W. (Institut fuer Physik, GKSS-Forschungszentrum Geesthacht GmbH, D-21502 Geesthacht (Germany))

1994-07-15T23:59:59.000Z

18

Lidar Report  

SciTech Connect

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.

Wollpert.

2009-04-01T23:59:59.000Z

19

Micropulse Lidar (MPL) Handbook  

SciTech Connect

The micropulse lidar (MPL) is a ground-based optical remote sensing system designed primarily to determine the altitude of clouds overhead. The physical principle is the same as for radar. 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 infered. Besides real-time detection of clouds, post-processing of the lidar return can also characterize the extent and properties of aerosol or other particle-laden regions.

Mendoza, A; Flynn, C

2006-05-01T23:59:59.000Z

20

Mobile multiwave lidar complexes  

Science Journals Connector (OSTI)

Multiwave mobile lidar complexes (MLCs) are designed and developed. A number of vehicle-based MLCs are built. The set of complex lidar probing data obtained with the help of MLCs is synchronised in space and time, covers a large area (the operation range of an MLC is 15 km), and is based on a unified methodological approach. The results of probing contain information on the concentration and physical nature of atmospheric aerosol, chemical composition of the gaseous phase of the atmosphere, wind and turbulence. The obtained data form the basis for a complex analysis of the ecological situation and prognosis of its development.

A S Boreysho; M A Konyaev; A V Morozov; A V Pikulik; A V Savin; A V Trilis; S Ya Chakchir; N I Boiko; Yu N Vlasov; S P Nikitaev; A V Rozhnov

2005-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

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

SciTech Connect

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

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

2008-02-06T23:59:59.000Z

22

Can Wind Lidars Measure Turbulence?  

Science Journals Connector (OSTI)

Modeling of the systematic errors in the second-order moments of wind speeds measured by continuous-wave (ZephIR) and pulsed (WindCube) lidars is presented. These lidars use the conical scanning technique to measure the velocity field. The model ...

A. Sathe; J. Mann; J. Gottschall; M. S. Courtney

2011-07-01T23:59:59.000Z

23

Raman Nanometrology of Graphene  

E-Print Network (OSTI)

13 Optical image of the graphene layers. . . . . .Micro-Raman Spectroscopy of Grapheneand Graphene Multi-Layers . . . . Raman Spectroscopy

Calizo, Irene Gonzales

2009-01-01T23:59:59.000Z

24

NASA DC-8 Airborne Scanning Lidar System  

Science Journals Connector (OSTI)

A scanning lidar system is being developed for installation on the NASA DC-8 atmospheric research aircraft to support...in-situ aerosol and gas measurements. Design and objectives of the DC-8 scanning lidar are p...

Norman B. Nielsen; Edward E. Uthe…

1997-01-01T23:59:59.000Z

25

Fluorescence lidar monitoring of historic buildings  

Science Journals Connector (OSTI)

Laser-induced fluorescence spectra detected with high-spectral-resolution lidar on the facades of the Baptistery and the Cathedral in Parma are presented and discussed. The...

Raimondi, Valentina; Cecchi, Giovanna; Pantani, Luca; Chiari, Roberto

1998-01-01T23:59:59.000Z

26

Raman spectra of terpenes  

Science Journals Connector (OSTI)

The available Raman spectral data on terpenic compounds are tabulated and reviewed. It is concluded that the identification of the constituents of a mixture of terpenes by Raman effect methods cannot give trus...

W. Rogie Angus

1938-11-01T23:59:59.000Z

27

Airborne Doppler Lidar Wind Field Measurements  

Science Journals Connector (OSTI)

A coherent Doppler lidar has been used in an aircraft to measure the 2-dimensional wind field in a number of different atmospheric situations. The lidar, a pulsed CO2 system, was installed in the NASA Convair 990. Galileo II, and flown in a ...

J. Bilbro; G. Fichtl; D. Fitzjarrald; M. Krause; R. Lee

1984-04-01T23:59:59.000Z

28

Definition: LiDAR | Open Energy Information  

Open Energy Info (EERE)

LiDAR LiDAR Jump to: navigation, search Dictionary.png LiDAR Light Detection and Ranging (LiDAR) is an active remote sensing technology that uses optical measurements of scattered light to find range (Young, 2006). Measurements can be made from aircraft- or land-based sensors. Distance to an object is determined by the time delay between transmission and detection of a laser pulse. It is accurate to within 0.1 m (at 1-m resolution, 0.3 m at 3-m resolution) and has the ability to measure the land surface elevation beneath the vegetation canopy. View on Wikipedia Wikipedia Definition Also Known As Light Detection And Ranging Related Terms DEM, Digital Elevation Model tran LikeLike UnlikeLike You like this.Sign Up to see what your friends like. smission lines,transmission line,transmission

29

Development of LED mini-Lidar  

Science Journals Connector (OSTI)

In this study, we aim to develop a mini-lidar system using a LED (Light Emitting Diode) as the light source for near-range measurement. Because LED is small size device and its...

Koyama, Moriaki; Shiina, Tatsuo

30

JOURNAL OF RAMAN SPECTROSCOPY J. Raman Spectrosc. 2005; 36: 864871  

E-Print Network (OSTI)

traditionally been utilized to indicate the phase transition. Comparisons with the Raman spectra of spodumene

Downs, Robert T.

31

Lidar characterization of crystalline silica generation and gravel plant  

E-Print Network (OSTI)

The lidar vertical pro?les and wind speed data were used toof wind speed and concentration (based on lidar verticalvertical plane at a given height, z, was calculated as the product of the wind speed

Trzepla-Nabaglo, K.; Shiraki, R.; Holm'en, B. A.

2006-01-01T23:59:59.000Z

32

Semiconductor Laser Lidar Wind Velocity Sensor for Turbine Control  

Science Journals Connector (OSTI)

A dual line-of-sight CW lidar that measures both wind speed and direction is presented. The wind lidar employs a semiconductor laser, which allows for inexpensive remote sensors geared...

Rodrigo, Peter John; Hu, Qi; Pedersen, Christian

33

7 - Raman spectroscopy of graphene  

Science Journals Connector (OSTI)

Abstract: The principles of Raman scattering and the properties of phonons and electrons in graphene are reviewed. The focus is on Raman spectroscopy of mono- and bilayer graphene, particularly perturbations that have a significant influence on the Raman spectra. The distinct behaviour of Raman modes of different orders is discussed.

M. Hulman

2014-01-01T23:59:59.000Z

34

Raman scattering in crystals  

SciTech Connect

A tutorial presentation is given of Raman scattering in crystals. The physical concepts are emphasized rather than the detailed mathematical formalism. Starting with an introduction to the concepts of phonons and conservation laws, the effects of photon-phonon interactions are presented. This interaction concept is shown for a simple cubic crystal and is extended to a uniaxial crystal. The correlation table method is used for determining the number and symmetry of the Raman active modes. Finally, examples are given to illustrate the relative ease of using this group theoretical method and the predictions are compared with measured Raman spectra. 37 refs., 17 figs., 6 tabs.

Edwards, D.F.

1988-09-30T23:59:59.000Z

35

Nuclear Raman spectroscopy  

Science Journals Connector (OSTI)

An experiment is described in which the nuclear analog to Raman spectroscopy has been applied to 57Fe. The results of the experiment are given, and future applications of...

DePaola, B D; Wagal, S S; Collins, C B

1985-01-01T23:59:59.000Z

36

LiDAR | Open Energy Information  

Open Energy Info (EERE)

LiDAR LiDAR Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: LiDAR Details Activities (10) Areas (5) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Remote Sensing Techniques Exploration Sub Group: Active Sensors Parent Exploration Technique: Active Sensors Information Provided by Technique Lithology: Stratigraphic/Structural: delineate faults, create high-resolution DEMS, quantify fault kinemaics, develop lineament maps Hydrological: Thermal: Cost Information Low-End Estimate (USD): 300.0030,000 centUSD 0.3 kUSD 3.0e-4 MUSD 3.0e-7 TUSD / sq. mile Median Estimate (USD): 850.0085,000 centUSD 0.85 kUSD 8.5e-4 MUSD 8.5e-7 TUSD / sq. mile High-End Estimate (USD): 1,300.00130,000 centUSD 1.3 kUSD 0.0013 MUSD 1.3e-6 TUSD / sq. mile

37

Systematic Sampling of Scanning Lidar Swaths  

E-Print Network (OSTI)

Popescu Proof of concept lidar research has, to date, examined wall-to-wall models of forest ecosystems. While these studies have been important for verifying lidars efficacy for forest surveys, complete coverage is likely not the most cost effective... year of my graduate studies. Also, to Jin Zhu and the other members of the Aerial Photography project at the Texas Forest Service for opening my eyes to the practical uses of GIS and remote sensing, their encouragement for me to obtain a graduate...

Marcell, Wesley Tyler

2011-02-22T23:59:59.000Z

38

Resonant Raman spectroscopy of nanotubes  

Science Journals Connector (OSTI)

...Raman spectroscopy in carbons: from nanotubes to diamond compiled by Andrea C. Ferrari...Robertson Resonant Raman spectroscopy of nanotubes Christian Thomsen 1 Stephanie Reich 2...The experimental situation in carbon nanotubes is reviewed in view of these criteria...

2004-01-01T23:59:59.000Z

39

E-Print Network 3.0 - absorption lidar performance Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

performed with the lidar25 operated simultaneously at Bordeaux (550 km away... . The NASA God- dard Space Flight Center (GSFC) mobile lidar system ... Source: Ecole Polytechnique,...

40

EN-025 Tools & Applications December 2008 Lidar Remote Sensing  

E-Print Network (OSTI)

IS LIDAR? Lidar (light detection and ranging system) is a relatively new type of active remote sensing are small-footprint, discrete return systems that record two to five returns for each emitted laser pulse fashion as an aerial photography camera. · An inertial measurement unit that records the pitch, yaw

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Ris-PhD-Report Complex Terrain and Wind Lidars  

E-Print Network (OSTI)

calculations over the same terrains. The lidar performance was also simulated with the commercial software WAs;#12;Author: Ferhat Bingöl Title: Complex terrain and wind lidars Division: Wind Energy Division Risø-PhD-52 and the comparison of the measurement data with the flow model outputs showed that the mean wind speed calculated

42

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

DOE Data Explorer (OSTI)

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

Jaffe, Todd

43

Raman accumulator as a fusion laser driver  

DOE Patents (OSTI)

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.

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

1982-03-31T23:59:59.000Z

44

Cladding-pumped Raman fibre laser sources.  

E-Print Network (OSTI)

??In this thesis, I investigate cladding-pumped Raman fibre lasers and amplifiers. Such devices, offering a novel way to generate Raman gain, combine the advantages of… (more)

Ji, Junhua

2011-01-01T23:59:59.000Z

45

2.1 RAMAN LIDAR PROFILING OF WATER VAPOR AND AEROSOLS OVER THE ARM SGP SITE  

E-Print Network (OSTI)

with satellite sensors. Accurate, high spatial and temporal resolution profiles of water vapor are also required+GOES) have been combined into a single product that takes advantage of both active and passive remote sensors with the use of narrowband (~0.4 nm bandpass) filters, reduces the background skylight and, therefore

46

NEW REMOTELY-OPERATED RAMAN-MIE-RAYLEIGH LIDAR IN THE HIGH CANADIAN ARCTIC  

E-Print Network (OSTI)

operation and alignment, data col- lection, and safety systems are controlled with custom software. 2 revolve around atmospheric energy trans- fer through both radiative and dynamic processes. As contributors

Duck, Thomas J.

47

The influence of LiDAR pulse density on the precision of inventory metrics in young unthinned Douglas-fir stands during initial and subsequent LiDAR acquisitions  

Science Journals Connector (OSTI)

LiDAR is an established technology that is increasingly being used to characterise spatial variation in stand metrics used in forest inventory. As the cost of LiDAR acquisition markedly declines with LiDAR pul...

Michael S Watt; Andrew Meredith; Pete Watt…

2014-08-01T23:59:59.000Z

48

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

DOE Data Explorer (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

49

Mitigation of Coastal Bluff Instability in San Diego County, California/Evaluating Seacliff Morphology and Erosion Control in San Diego County Using LIDAR and GIS  

E-Print Network (OSTI)

County Using LIDAR and GIS In order to evaluate seacliffgeographic information systems (GIS) analysis. LIDAR is the

Ashford, Scott

2005-01-01T23:59:59.000Z

50

Superradiant Raman Laser Magnetometer  

E-Print Network (OSTI)

We demonstrate a proof-of-principle magnetometer that relies on the active oscillation of a cold atom Raman laser to continuously map a field-sensitive atomic phase onto the phase of the radiated light. We demonstrate wideband sensitivity during continuous active oscillation, as well as narrowband sensitivity in passive Ramsey-like mode with translation of the narrowband detection in frequency using spin-echo techniques. The sensor operates with a sensitivity of 190 pT/Hz^(1/2) at 1 kHz and effective sensing volume of 2 * 10^-3 mm^3. Fundamental quantum limits on the magnetic field sensitivity of an ideal detector are also considered.

Weiner, Joshua M; Bohnet, Justin G; Chen, Zilong; Thompson, James K

2012-01-01T23:59:59.000Z

51

LiDAR (Laney, 2005) | Open Energy Information  

Open Energy Info (EERE)

LiDAR (Laney, 2005) LiDAR (Laney, 2005) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: LiDAR (Laney, 2005) Exploration Activity Details Location Unspecified Exploration Technique LiDAR Activity Date Usefulness not indicated DOE-funding Unknown Notes Design of Sampling Strategies to Detect CO2 Emissions From Hidden Geothermal Systems, Lewicki, Oldenburg and Kennedy. The objective of this project is to investigate geothermal CO2 monitoring in the near surface as a tool to discover hidden geothermal reservoirs. A primary goal of this project is to develop an approach that places emphasis on cost and time-efficient near-surface exploration methods and yields results to guide and focus more cost-intensive geophysical measurements, installation of

52

ARM - Field Campaign - Boundary Layer CO2 Using CW Lidar  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsBoundary Layer CO2 Using CW Lidar 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 Description 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 Facility at ACRF's Southern Great Plains (SGP) site as part of the Climate Sources and Sink (CO2) Intensive Operational Period (IOP), using a CW lidar. The objective of the flights was to validate, by demonstration and comparison with SGP ground observations, the performance of the ITT system when used in conjunction with retrieval

53

URBAN MODELING FROM LIDAR DATA IN AN INTEGRATED GIS ENVIRONMENT  

E-Print Network (OSTI)

are analyzed and possible solutions are proposed by fusing lidar data with other image data. Study shows: it allows rapid generation large-scale DTM (digital terrain model); is daylight independent; is relatively

Shan, Jie

54

Comparison of 2- and 10-µm Coherent Doppler Lidar Performance  

Science Journals Connector (OSTI)

The performance of 2- and 10-µm coherent Doppler lidar is presented in terms of the statistical distribution of the maximum-likelihood velocity estimator from simulations for fixed range resolution and fixed velocity search space as a function of ...

Rod Frehlich

1995-04-01T23:59:59.000Z

55

Cirrus Classification at Midlatitude from Systematic Lidar Observations  

Science Journals Connector (OSTI)

Systematic cirrus lidar measurements performed in the south of France during 2000 are analyzed statistically to search for cloud classes. The classes are based on cloud characteristics (cloud thickness, light backscattering efficiency, and its ...

P. Keckhut; F. Borchi; S. Bekki; A. Hauchecorne; M. SiLaouina

2006-02-01T23:59:59.000Z

56

Oil spill fluorosensing lidar for inclined onshore or shipboard operation  

Science Journals Connector (OSTI)

An oil spill detection fluorosensing lidar for onshore or shipboard operation is described. Some difficulties for its operation arise from the inclined path of rays. This is due to...

Karpicz, Renata; Dementjev, Andrej; Kuprionis, Zenonas; Pakalnis, Saulius; Westphal, Rainer; Reuter, Rainer; Gulbinas, Vidmantas

2006-01-01T23:59:59.000Z

57

Raman Spectroscopic Studies of Silicotitanates  

SciTech Connect

Silicotitanates are nanoporous materials that have been used as selective ion exchangers for removing cesium from waste streams and catalysts for promoting oxidation and hydroxylation reactions. The local bonding configurations and network charge distribution are known to influence the selectivity and reactivity of these compounds. We have synthesized a group of new silicotitanates using sol-gel and solid state techniques. Raman spectroscopy has been used to systematically examine the vibrational behavior of these compounds. By correlating the variations of Raman spectra with titanium coordinations of these compounds, the relationship between Raman shifts and the local bonding configurations around silicon and titanium is proposed.

Su, Yali; Balmer, Mari Lou; Bunker, Bruce C.

2000-07-19T23:59:59.000Z

58

LIDAR Wind Speed Measurements of Evolving Wind Fields  

SciTech Connect

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.

Simley, E.; Pao, L. Y.

2012-07-01T23:59:59.000Z

59

Raman Spectrum of Heavy Water  

Science Journals Connector (OSTI)

... . of 99.2 gm./lOO gm. D2O ( 1.1049) supplied by the Norsk Hydro-Elektrisk Kvaelstofaktieselskab. The Raman spectrum of the substance was photographed with a Hilger ...

R. ANANTHAKRISHNAN

1935-10-05T23:59:59.000Z

60

Raman Spectroscopy of Microbial Pigments  

Science Journals Connector (OSTI)

...minireview, Raman spectroscopy has several advantages for pigment and carotenoid work. The...BF01923559 . 71. Garcia-Pichel, F . 1998. Solar ultraviolet and the evolutionary history...signal strength, adaptive strategies, solar radiation, and humidity. Astrobiology...

Jan Jehli?ka; Howell G. M. Edwards; Aharon Oren

2014-03-28T23:59:59.000Z

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

UV Raman spectroscopy of hydrocarbons  

Science Journals Connector (OSTI)

...Nitrogen chemistry Petroleum Physics methods Spectrum Analysis...Grasselli, J. G. 1991 The handbook of infrared and Raman characteristic...13081313. Weast, R. C. 1977 CRC handbook of chemistry and physics, 58th edn, pp. C80C548...

2004-01-01T23:59:59.000Z

62

Mapping surface fuels using LIDAR and multispectral data fusion for fire behavior modeling  

E-Print Network (OSTI)

, LIDAR derived data provides accurate estimates of surface fuel parameters efficiently and accurately over extensive areas of forests. This study demonstrates the importance of using accurate maps of fuel models derived using new LIDAR remote sensing...

Mutlu, Muge

2009-05-15T23:59:59.000Z

63

Lidar Scanning of Momentum Flux in and above the Atmospheric Surface Layer  

Science Journals Connector (OSTI)

Methods to measure the vertical flux of horizontal momentum using both continuous wave and pulsed Doppler lidar profilers are evaluated. The lidar measurements are compared to momentum flux observations performed with sonic anemometers over flat ...

J. Mann; A. Peña; F. Bingöl; R. Wagner; M. S. Courtney

2010-06-01T23:59:59.000Z

64

Alternate spatial sampling approaches for ecosystem structure inventory using spaceborne lidar  

E-Print Network (OSTI)

used in aircraft lidar remote sensing where power, heat, and reliability are less of a concern since January 2011 Accepted 29 January 2011 Available online 23 March 2011 Keywords: Lidar Remote sensing Laser collected in transects and should be considered for future lidar remote sensing missions. © 2011 Elsevier

Lefsky, Michael

65

Advanced Lidars for ARM: What Would We Get?  

NLE Websites -- All DOE Office Websites (Extended Search)

CMWG Breakout Session CMWG Breakout Session 2009 ARM Science Team Meeting Advanced Lidars for ARM: What Would We Get? Dave Turner, Ed Eloranta University of Wisconsin - Madison CMWG Breakout Session 2009 ARM Science Team Meeting What is an "Advanced Lidar?" (1) * Ceilometer - Max range ~7km, unpolarized, uncalibrated * Micropulse lidar (MPL) - Sensitive to clouds & aerosols throughout troposphere - Small telescope, rep rate is 1.5 kHz, microjoules of power - Loses sensitivity to cirrus in upper trop during the day - Polarization sensitive - Uncalibrated * Backscatter signals measured by both the MPL and the Ceilometer are convolutions of molecular and particle scattering events - Unable to determine particle extinction without significant assumptions - Main use by ARM has been to determine layer boundaries

66

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

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsLidar support for ICECAPS at Summit, Greenland 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 - 2014.10.31 Lead Scientist : David Turner Description Beginning in May 2010, the Integrated Characterization of Energy, Clouds, Atmospheric State, and Precipitation over Summit (ICECAPS) project, funded through the National Science Foundation's Arctic Observing Network, is deploying a suite of remote sensors at Summit, Greenland, for four years. With dining facilities and communications gear, the "Big House" at Summit Station serves as the central gathering area for site researchers. (Photo courtesy Summit Station.)

67

A study on Raman Injection Laser  

E-Print Network (OSTI)

The Raman Injection Laser is a new type of laser which is based on triply resonant stimulated Raman scattering between quantum confined states within the active region of a Quantum Cascade Laser that serves as an internal optical pump. The Raman...

Liu, Debin

2005-11-01T23:59:59.000Z

68

JOURNAL OF RAMAN SPECTROSCOPY J. Raman Spectrosc. 2003; 34: 769775  

E-Print Network (OSTI)

Science (www.interscience.wiley.com). DOI: 10.1002/jrs.1051 Raman spectroscopic study of spodumene (LiAlSi2O6 spectrum of a natural specimen of the pyroxene spodumene, from its low-pressure (C2/c) to its high, was not observed. Copyright 2003 John Wiley & Sons, Ltd. KEYWORDS: spodumene; pyroxene; pressure-induced phase

Downs, Robert T.

69

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

SciTech Connect

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.

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

2014-05-01T23:59:59.000Z

70

Inversion-free, noiseless Raman echoes  

E-Print Network (OSTI)

Using double optical Raman rephasing, an inversion-free resonant Raman echo is studied in an inhomogeneously broadened spin ensemble of a solid medium, where the Raman optical field-excited spin coherence has a frozen propagation vector. Unlike photon echoes whose quantum memory application is strictly limited due to \\pi rephasing pulse-induced population inversion causing quantum noises, the optical Raman field-excited spin echo is inherently silent owing to the frozen propagation vector. Thus, the doubly rephased Raman echo can be directly applied for quantum interface in a population inversion-free environment.

Byoung S. Ham

2011-11-20T23:59:59.000Z

71

INTEGRATED LIDAR & PHOTOGRAMMETRIC DOCUMENTATION OF THE RED GULCH DINOSAUR  

E-Print Network (OSTI)

101 INTEGRATED LIDAR & PHOTOGRAMMETRIC DOCUMENTATION OF THE RED GULCH DINOSAUR TRACKSITE (WYOMING. At the First International Symposium on Dinosaur Tracks and Traces in 1989, concerns were expressed about collection and imaging techniques used to document fossil resources. Digital techniques are typically non

Falkingham, Peter

72

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

Open Energy Info (EERE)

LiDAR At Chocolate Mountains Area (Alm, Et Al., 2010) LiDAR At Chocolate Mountains Area (Alm, Et Al., 2010) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: LiDAR At Chocolate Mountains Area (Alm, Et Al., 2010) Exploration Activity Details Location Chocolate Mountains Area Exploration Technique LiDAR Activity Date Usefulness useful DOE-funding Unknown Notes Recent exploration includes a high resolution 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 the active tectonic environment, and identify Holocene structures, which are common conduits for upwelling geothermal fluids. References Steve Alm, S. Bjornstad, M. Lazaro, A. Sabin1, D. Meade, J. Shoffner, W. C. Huang, J. Unruh, M. Strane, H. Ross (2010) Geothermal

73

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

NLE Websites -- All DOE Office Websites (Extended Search)

ProductsMicroPulse LIDAR Cloud Optical Depth ProductsMicroPulse LIDAR Cloud Optical Depth (MPLCOD) Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Evaluation Product : MicroPulse LIDAR Cloud Optical Depth (MPLCOD) 1999.05.01 - 2004.05.14 Site(s) SGP General Description The MPLCOD VAP retrieves the column cloud visible optical depth using LIDAR derived backscatter from the MPLNOR (Micro Pulse Lidar Normalized Backscatter) and radiosonde thermodynamic profiles. The optical depth retrieval is derived following Comstock et al. (2001), which retrieves visible optical depth and layer average backscatter-to-extinction ratio (k) at the lidar wavelength for each backscatter profile. Data Information Data Directory Contacts Principal Investigator Jennifer Comstock (509) 372-424

74

Raman activity in synchronously dividing bacteria  

SciTech Connect

Using a spectrometer equipped with an optical-multichannel analyzer as the detector (OMA), we have observed the Stokes laser-Raman spectra of metabolically active Escherichia coli and Bacillus megaterium from 100 - 2100 cm/sup -1/. After lengthy investigation, no Raman lines attributable to the metabolic process nor the cells themselves were found. Previous Raman spectra of active bacteria cannot be used to support nonlinear theories in biology. 34 refs., 9 figs.

Layne, S.P.

1985-01-01T23:59:59.000Z

75

An Automated Raman Device for Gout Diagnosis  

Science Journals Connector (OSTI)

This study reports an automated Raman device to identify crystals in synovial aspirates from patients with gout symptoms. Combined with sample preparation, the device could diagnose...

Li, Bolan

76

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

SciTech Connect

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.

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

2014-02-01T23:59:59.000Z

77

Ground-truth aerosol lidar observations: can the Klett solutions obtained from ground and space be equal for the same aerosol case?  

Science Journals Connector (OSTI)

Upcoming multiyear satellite lidar aerosol observations need strong support by a worldwide ground-truth lidar network. In this context the question arises as to whether the ground...

Ansmann, Albert

2006-01-01T23:59:59.000Z

78

NASA’s Space Lidar Measurements of Earth and Planetary Surfaces  

Science Journals Connector (OSTI)

This presentation will give an overview of history, ongoing work, and plans for using space lidar for measurements of planetary surfaces.

Abshire, James B

79

E-Print Network 3.0 - absorption lidar system Sample Search Results  

NLE Websites -- All DOE Office Websites (Extended Search)

light absorption... lidar system are proposed ... Source: Zavrtanik, Marko - Experimental Particle Physics Department, Jozef Stefan Institute Collection: Physics 77 Atmos. Chem....

80

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

Open Energy Info (EERE)

Structural Analysis of Southern Dixie Valley using LiDAR and Low-Sun-Angle Aerial Photography, NAS Fallon Geothermal Exploration Project, Dixie Valley, Nevada Jump to: navigation,...

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

High-resolution lidar observations of mesospheric sodium and implications for adaptive optics  

Science Journals Connector (OSTI)

Observations of sodium density variability in the upper mesosphere/lower thermosphere, obtained using a high-resolution lidar system, show rapid fluctuations in the sodium centroid...

Pfrommer, Thomas; Hickson, Paul

2010-01-01T23:59:59.000Z

82

Comparison of temperature and humidity profiles with elastic-backscatter lidar data  

SciTech Connect

This contribution analyzes elastic-backscatter lidar data and temperature and humidity profiles from radiosondes acquired in Barcelona in July 1992. Elastic-backscatter lidar data reveal the distribution of aerosols within the volume of atmosphere scanned. By comparing this information with temperature and humidity profiles of the atmosphere at a similar time, we are able to asses de relationship among aerosol distribution and atmospheric stability or water content, respectively. Comparisons have shown how lidar`s revealed layers of aerosols correspond to atmospheric layers with different stability condition and water content.

Soriano, C. [Universidad Politecnica de Cataluna, Barcelona (Spain)]|[Los Alamos National Lab., NM (United States); Buttler, W.T. [Los Alamos National Lab., NM (United States); Baldasano, J.M. [Universidad Politecnica de Cataluna, Barcelona (Spain)

1995-04-01T23:59:59.000Z

83

LIDAR Wind Speed Measurements of Evolving Wind Fields  

SciTech Connect

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 that are 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 the validity of physicist G.I. Taylor's 1938 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 using the National Renewable Energy Laboratory's (NREL's) 5-megawatt turbine model to create a more realistic measurement model. A simple model of wind evolution was applied to a frozen wind field that was used in previous studies to investigate the effects of varying the intensity of wind evolution. LIDAR measurements were also evaluated using a large eddy simulation (LES) of a stable boundary layer that was provided by the National Center for Atmospheric Research. The LIDAR measurement scenario investigated consists of a hub-mounted LIDAR that scans a circle of points upwind of the turbine in order to estimate the wind speed component in the mean wind direction. Different combinations of the preview distance that is located upwind of the rotor and the radius of the scan circle were analyzed. It was found that the dominant source of measurement error for short preview distances is the detection of transverse and vertical wind speeds from the line-of-sight LIDAR measurement. It was discovered in previous studies that, in the absence of wind evolution, the dominant source of error for large preview distances is the spatial averaging caused by the LIDAR's sampling volume. However, by introducing wind evolution, the dominant source of error for large preview distances was found to be the coherence loss caused by evolving turbulence. Different measurement geometries were compared using the bandwidth for which the measurement coherence remained above 0.5 and also the area under the measurement coherence curve. Results showed that, by increasing the intensity of wind evolution, the measurement coherence decreases. Using the coherence bandwidth metric, the optimal preview distance for a fixed-scan radius remained almost constant for low and moderate amounts of wind evolution. For the wind field with the simple wind evolution model introduced, the optimal preview distance for a scan radius of 75% blade span (47.25 meters) was found to be 80 meters. Using the LES wind field, the optimal preview distance was 65 meters. When comparing scan geometries using the area under the coherence curve, results showed that, as the intensity of wind evolution increases, the optimal preview distance decreases.

Simley, E.; Pao, L. Y.; Kelley, N.; Jonkman, B.; Frehlich, R.

2012-01-01T23:59:59.000Z

84

Raman and XPS characterization of fuel-cladding interactions...  

NLE Websites -- All DOE Office Websites (Extended Search)

interactions using miniature specimens. Raman and XPS characterization of fuel-cladding interactions using miniature specimens. Abstract: Laser Raman spectroscopy was...

85

Operando Raman and Theoretical Vibration Spectroscopy of Non...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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

86

Adiabatic Tip-Plasmon Focusing for Nano-Raman Spectroscopy. ...  

NLE Websites -- All DOE Office Websites (Extended Search)

Adiabatic Tip-Plasmon Focusing for Nano-Raman Spectroscopy. Adiabatic Tip-Plasmon Focusing for Nano-Raman Spectroscopy. Abstract: True nanoscale optical spectroscopy requires the...

87

Multiphonon Raman scattering in graphene  

Science Journals Connector (OSTI)

We report on multiphonon Raman scattering in graphene samples. Higher-order combination modes involving three and four phonons are observed in single-layer, bilayer, and few-layer graphene samples prepared by mechanical exfoliation. The intensity of the higher-order phonon modes (relative to the G peak) is highest in single-layer graphene and decreases with increasing layers. In addition, all higher-order modes are observed to upshift in frequency almost linearly with increasing graphene layers, betraying the underlying interlayer van der Waals interactions.

Rahul Rao; Derek Tishler; Jyoti Katoch; Masa Ishigami

2011-09-12T23:59:59.000Z

88

Using LiDAR and normalized difference vegetation index to remotely determine LAI and percent canopy cover at varying scales  

E-Print Network (OSTI)

: (1) Develop scanning LiDAR and multispectral imagery methods to estimate PCC and LAI over both hardwood and coniferous forests; (2) investigate whether a LiDAR and normalized difference vegetation index (NDVI) data fusion through linear regression...

Griffin, Alicia Marie Rutledge

2009-05-15T23:59:59.000Z

89

Raman scattering from sp2 carbon clusters  

Science Journals Connector (OSTI)

Raman spectra of B ion-implanted glassy carbon (GC) and hydrogenated amorphous carbon (a-C:H) films have been measured as a function of polarization direction of the scattered light and excitation wavelength. Raman bands of GC implanted heavily with a fluence of more than 5×1015 B ions/cm2 and a-C:H films show a frequency-independent depolarization ratio, suggesting the existence of sp2 carbon clusters in these samples. It was found that Raman spectra of GC implanted heavily with a fluence of more than 5×1015 B ions/cm2 varied with the excitation wavelength. From a comparative study of the heavily implanted GC and a-C:H films, the variation of the Raman spectra with the excitation wavelength observed for the heavily implanted GC is interpreted in terms of ?-?* resonant Raman scattering from sp2 carbon clusters having various sizes.

M. Yoshikawa; N. Nagai; M. Matsuki; H. Fukuda; G. Katagiri; H. Ishida; A. Ishitani; I. Nagai

1992-09-15T23:59:59.000Z

90

Raman Spectra of Polyatomic Gases  

Science Journals Connector (OSTI)

Raman spectra of gaseous CO2, N2O, NH3, CH4 and C2H4 have been photographed using the line ?2536 of mercury as the exciting radiation. Vibrational transitions have been observed in all the gases investigated, and rotational transitions in the cases of NH3 and CH4. For the frequency shifts due to the vibrational transitions, the following numerical values (in cm-1) have been found: CO2: 1264.5; 1285.1; 1387.7; 1408.4.CH4: 2914.8; 3022.1; 3071.5.N2O: 1281.8C2H4: 1342.4; 1623.3; 2880.1; 3019.3; 3240.3; 3272.3.NH3: 3333.6  Raman spectra of liquid NH3 have been photographed and found to give the two frequency shifts: 3298.4 and 3214.5. In the case of gaseous NH3, pure rotational transitions lead to a moment of inertia having the value I0=2.79×10-40. In the case of methane, the positive and negative branches of the 3022.1 band lead to the value I0=5.17×10-40. The relations between these data and infra-red absorption data are discussed.

R. G. Dickinson, R. T. Dillon, and F. Rasetti

1929-08-15T23:59:59.000Z

91

Impact of airborne Doppler wind lidar profiles on numerical simulations of a tropical cyclone  

E-Print Network (OSTI)

Click Here for Full Article Impact of airborne Doppler wind lidar profiles on numerical simulations Regional Campaign (TPARC) field experiment in 2008, an airborne Doppler wind lidar (DWL) was onboard the U measurements on the numerical simulation of Typhoon Nuri (2008) in its formation phase. With an advanced

Pu, Zhaoxia

92

An initial assessment of the Robust And Compact Hybrid Environmental Lidar (RACHEL)  

E-Print Network (OSTI)

the greatest source of uncertainty in global climate models [1]. Their rapid variability in both time and space lidar techniques, the extinction and backscat- ter coefficients of an aerosol can be measured simul the assembly of a high-density, automated lidar network is impractical, despite the sig- nificant science gains

Oxford, University of

93

A new cloud and aerosol layer detection method based on micropulse lidar measurements  

E-Print Network (OSTI)

A new cloud and aerosol layer detection method based on micropulse lidar measurements Chuanfeng algorithm to detect aerosols and clouds based on micropulse lidar measurements. A semidiscretization is then introduced. Combined with empirical threshold values, we determine if the signal waves indicate clouds

Li, Zhanqing

94

3D Turbulence Measurements Using Three Synchronous Wind Lidars: Validation against Sonic Anemometry  

Science Journals Connector (OSTI)

This paper presents a technique to measure the time series of the three components of the wind vector at a point in space from synchronous measurements of three scanning Doppler wind lidars. Knowing the position of each lidar on the ground and the ...

Fernando Carbajo Fuertes; Giacomo Valerio Iungo; Fernando Porté-Agel

2014-07-01T23:59:59.000Z

95

All Sky Camera, LIDAR and Electric Field Meter: auxiliary instruments for the ASTRI SST-2M prototype  

E-Print Network (OSTI)

ASTRI SST-2M is the end-to-end prototype telescope of the Italian National Institute of Astro- physics, INAF, designed to investigate the 10-100 TeV band in the framework of the Cherenkov Telescope Array, CTA. The ASTRI SST-2M telescope has been installed in Italy in September 2014, at the INAF ob- serving station located at Serra La Nave on Mount Etna. The telescope is foreseen to be completed and fully operative in spring 2015 including auxiliary instrumentation needed to support both operations and data anal- ysis. In this contribution we present the current status of a sub-set of the auxiliary instruments that are being used at the Serra La Nave site, namely an All Sky Camera, an Electric Field Meter and a Raman Lidar devoted, together with further instrumentation, to the monitoring of the atmospheric and environmental conditions. The data analysis techniques under development for these instruments could be applied at the CTA sites, where similar auxiliary instrumentation will be installed.

Leto, Giuseppe; Bellassai, Giancarlo; Bruno, Pietro; Maccarone, Maria Concetta; Martinetti, Eugenio

2015-01-01T23:59:59.000Z

96

First Verification Test and Wake Measurement Results Using a SHIP-LIDAR System  

Science Journals Connector (OSTI)

Abstract Measuring wind offshore in deep water depths will be a future challenge. Where the sea bed foundation installation for fixed meteorological masts is impossible, floating systems tend to be a sophisticated solution. In addition to the use of moored lidar- buoy systems, ship-lidar systems are an alternative solution for a number of different applications. In this paper we describe general aspects of motion influences on lidar measurements as well as two motion-correction methods for motion-influenced lidar measurements. The implementation of the ship-lidar system and different scanning modes will be presented. First measurements were carried out as part of the EERA-DTOC project. Hence a verification of one of the two correction algorithms as well as first results from wake measurements behind the Alpha Ventus offshore wind farm will be shown. This comprises distinct wind speed wake losses and an increasing turbulence intensity in a distance of approximately 2 km behind the wind farm.

G. Wolken-Möhlmann; J. Gottschall; B. Lange

2014-01-01T23:59:59.000Z

97

Short-range, Non-contact Detection of Surface Contamination Using Raman Lidar Arthur J. Sedlacek, III*  

E-Print Network (OSTI)

-time detection and identification of bulk amounts of substances on surfaces. Optical spectroscopic methods detection and identification of chemical spills is discussed. The new chemical sensor combines the spectral-range (meters to tens of meters), non-contact detection and identification of unknown substances on surfaces

98

Inelastic neutron and low-frequency Raman scattering in a niobium-phosphate glass for Raman gain applications  

E-Print Network (OSTI)

Inelastic neutron and low-frequency Raman scattering in a niobium-phosphate glass for Raman gain: Raman scattering; Neutron scattering; Raman gain; Boson peak We present measurements of the vibrational, extracted from specific-heat or neutron scattering measurements [7,8]. Only very recently two of the present

Schirmacher, Walter

99

Lidar-based Research and Innovation at DTU Wind Energy – a Review  

Science Journals Connector (OSTI)

As wind turbines during the past decade have increased in size so have the challenges met by the atmospheric boundary-layer meteorologists and the wind energy society to measure and characterize the huge-volume wind fields surpassing and driving them. At the DTU Wind Energy test site "Østerild" for huge wind turbines, the hub-height of a recently installed 8 MW Vestas V164 turbine soars 143 meters up above the ground, and its rotor of amazing 164 meters in diameter make the turbine tips flicker 225 meters into the sky. Following the revolution in photonics-based telecommunication at the turn of the Millennium new fibre-based wind lidar technologies emerged and DTU Wind Energy, at that time embedded within Rise National Laboratory, began in collaboration with researchers from wind lidar companies to measure remote sensed wind profiles and turbulence structures within the atmospheric boundary layer with the emerging, at that time new, all-fibre-based 1.55 ? coherent detection wind lidars. Today, ten years later, DTU Wind Energy routinely deploys ground-based vertical profilers instead of met masts for high-precision measurements of mean wind profiles and turbulence profiles. At the departments test site "Høvsøre" DTU Wind Energy also routinely calibrate and accredit wind lidar manufactures wind lidars. Meanwhile however, new methodologies for power curve assessment based on ground-based and nacelle based lidars have also emerged. For improving the turbines power curve assessments and for advancing their control with feed-forward wind measurements experience has also been gained with wind lidars installed on turbine nacelles and integrated into the turbines rotating spinners. A new mobile research infrastructure WindScanner.dk has also emerged at DTU Wind Energy. Wind and turbulence fields are today scanned from sets of three simultaneously in space and time synchronized scanning lidars. One set consists of three fast scanning continuous-wave based wind lidars (short-range system), and another consisting of three synchronized pulsed wind lidar systems (long-range system). Today, wind lidar profilers and WindScanners are routinely deployed and operated during field tests and measurement campaigns. Lidars have been installed and operated from ground, on offshore platforms, and also as scanning lidars integrated in operating turbines. As a result, wind profiles and also detailed 3D scanning of wind and turbulence fields have been achieved: 1) of the free wind aloft, 2) over complex terrain, 3) at coastal ranges with land-sea interfaces, 4) offshore, 5) in turbine inflow induction zone, and 6) of the complex and turbulent flow fields in the wakes inside wind parks.

T Mikkelsen

2014-01-01T23:59:59.000Z

100

Simultaneous Neutron Scattering and Raman Scattering  

Science Journals Connector (OSTI)

The capability to make simultaneous neutron and Raman scattering measurements at temperatures between 1.5 and 450 K has been developed. The samples to be investigated are attached to...

Adams, Mark A; Parker, Stewart F; Fernandez-Alonso, Felix; Cutler, David J; Hodges, Christopher; King, Andrew

2009-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Complex-optical-field lidar system for range and vector velocity measurement  

E-Print Network (OSTI)

Complex-optical-field lidar system for range and vector velocity measurement Shuang Gao,1,2 Maurice O’Sullivan,3 and Rongqing Hui2,* 1Department of Electronic Engineering and Information Science, University of Science and Technology of China... lidar system based on the measurement of complex optical field is demonstrated for the first time. An electro-optic in- phase/quadrature (I/Q) modulator is used in the lidar transmitter to realize carrier-suppressed complex optical field modulation...

Gao, Shuang; Sullivan, Maurice O.; Hui, Rongqing

2012-11-01T23:59:59.000Z

102

Ultraviolet Resonant Raman Enhancements in the Detection of Explosives  

SciTech Connect

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 enhancements for solid HE samples.

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

2009-06-03T23:59:59.000Z

103

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

Open Energy Info (EERE)

Twenty-Nine Palms Area (Page, Et Al., 2010) Twenty-Nine Palms Area (Page, Et Al., 2010) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: LiDAR At Twenty-Nine Palms Geothermal Area (Page, Et Al., 2010) Exploration Activity Details Location Twenty-Nine Palms Geothermal Area Exploration Technique LiDAR Activity Date Usefulness useful DOE-funding Unknown Notes Primary LiDAR application to this project was Airborne Laser Swath Mapping (ALSM). This particular application was used to gather data over a specific land area then used to create a Digital Elevation Model (DEM) with a resolution of approximately 1m in the horizontal direction and 10cm in the vertical direction. The LiDAR data gathered for MCAGCC was analyzed in conjunction with other data, such as aerial photography and field

104

Algorithms and Software Tools for Extracting Coastal Morphological Information from Airborne LiDAR Data  

E-Print Network (OSTI)

coastal forms and processes. This research aims at developing algorithms for automatically extracting coastal morphological information from LiDAR data. The primary methods developed by this research include automated algorithms for beach profile feature...

Gao, Yige

2010-07-14T23:59:59.000Z

105

SciTech Connect: Field Test Results from Lidar Measured Yaw Control...  

NLE Websites -- All DOE Office Websites (Extended Search)

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...

106

Fully automatic calibration of LIDAR and video streams from a vehicle  

E-Print Network (OSTI)

This work describes a fully automatic technique to calibrate a geometric mapping between lidar and video feeds on a mobile ground-based platform. This data association is a crucial first step for any multi-modal scene ...

Bileschi, Stanley M.

107

E-Print Network 3.0 - absorption lidar sensitivity Sample Search...  

NLE Websites -- All DOE Office Websites (Extended Search)

has been modified in recent years (McGee et al., 1991, 1993,20 1995). A Xe... . The NASA God- dard Space Flight Center (GSFC) mobile lidar system was deployed at the Observa-...

108

Studying Clouds and Aerosols with Lidar Depolarization Ratio and Backscatter Relationships  

E-Print Network (OSTI)

comparison of mineral dust aerosol retrievals from two instruments, MODIS and CALIPSO lidar. And, we implement and evaluate a new mineral dust detection algorithm based on the analysis of thin dust radiative signature. In comparison, three commonly used...

Cho, Hyoun-Myoung

2012-02-14T23:59:59.000Z

109

Narrowband sodium lidar for the measurements of mesopause region temperature and wind  

Science Journals Connector (OSTI)

We report here a narrowband high-spectral resolution sodium temperature/wind lidar recently developed at the University of Science and Technology of China (USTC) in Hefei, China...

Li, Tao; Fang, Xin; Liu, Wei; Gu, Sheng-Yang; Dou, Xiankang

2012-01-01T23:59:59.000Z

110

LiDAR At Dixie Valley Geothermal Area (Helton, Et Al., 2011)...  

Open Energy Info (EERE)

Fallon Geothermal Exploration Project. Notes High resolution LiDAR and 1:12000 scale low-sun-angle aerial photography was used in southern Dixie Valley to help better characterize...

111

Digital Outcrop Models: Applications of Terrestrial Scanning Lidar Technology in Stratigraphic Modeling  

Science Journals Connector (OSTI)

...passive sensors. All but the most extreme atmospheric and lighting conditions will have little effect on terrestrial lidar...Changes, Cycles, and Reservoirs on Carbonate Platforms in Greenhouse and Ice-house Worlds: SEPM, Short Course no. 35, 147...

J.A. Bellian; C. Kerans; D.C. Jennette

112

2.5 MHz Line-Width High-Energy, 2µm Coherent Wind Lidar Transmitter  

Science Journals Connector (OSTI)

The design of a diode pumped, injection seeded MOPA with a transform limited line width and diffraction limited beam quality is presented. This lidar transmitter produces over 300mJ...

Petros, Mulugeta; Yu, Jirong; Trieu, Bo; Bai, Yingxin; Petzar, Paul; Singh, Upendra N; Reithmaier, Karl

113

Development of All-fiber Coherent Doppler Lidar to Measure Atmosphere Wind Speed  

Science Journals Connector (OSTI)

An all-fiber pulsed coherent Doppler lidar is developed to measure wind profiles. The maximum horizontal and vertical range for wind speed is 4.2km and 2km with speed accuracy of...

Liu, Jiqiao; Chen, Weibiao; Zhu, Xiaopeng

114

NESTED HIGH RESOLUTION SIMULATION AND LIDAR VALIDATION OF A LAND BREEZE CIRCULATION  

E-Print Network (OSTI)

NESTED HIGH RESOLUTION SIMULATION AND LIDAR VALIDATION OF A LAND BREEZE CIRCULATION by GIJS DE BOER local forcing. A wide range of scales is simulated using the nesting capability of the University

Eloranta, Edwin W.

115

A Portable Airborne Scanning Lidar System for Ocean and Coastal Applications  

Science Journals Connector (OSTI)

A portable compact airborne scanning lidar system based on the Riegl LMS-Q240i has been developed and its functionality demonstrated for oceanographic and coastal measurements. Differential GPS (DGPS) and an inertial navigation system are ...

Benjamin D. Reineman; Luc Lenain; David Castel; W. Kendall Melville

2009-12-01T23:59:59.000Z

116

Lidar-Observed Stress Vectors and Veer in the Atmospheric Boundary Layer  

Science Journals Connector (OSTI)

This study demonstrates that a pulsed wind lidar is a reliable instrument for measuring angles between horizontal vectors of significance in the atmospheric boundary layer. Three different angles are considered: the wind turning, the angle between ...

Jacob Berg; Jakob Mann; Edward G. Patton

2013-09-01T23:59:59.000Z

117

A Simple Model for Correcting Sodar and Lidar Errors in Complex Terrain  

Science Journals Connector (OSTI)

Ground-based sensing of wind profiles by sodars and lidars is becoming the standard for wind energy and other applications. However, there remain difficulties in complex terrain since the instruments sense wind components in spatially separated ...

Stuart Bradley

2012-12-01T23:59:59.000Z

118

Development of a lidar polarimeter technique of measuring suspended solids in water  

E-Print Network (OSTI)

DEVELOPMENT OF A LIDAR POLARIMETER TECHNIQUE OF MEASURING SUSPENDED SOLIDS IN WATER A Thesis by DAVID W. PRESLEY Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE May 1980 Major Subject; Electrical Engineering DEVELOPMENT OF A LIDAR POLARIMETER TECHNIQUE OF MEASURING SUSPENDED SOLIDS IN WATER A Thesis by DAVID W, PRESLEY Approved as to sty1e and content by: Chairman of Committee H d of Department...

Presley, David W

1980-01-01T23:59:59.000Z

119

Raman gas analyzer for determining the composition of natural gas  

Science Journals Connector (OSTI)

We describe a prototype of a Raman gas analyzer designed for measuring the composition of natural gas. Operation of the gas analyzer was tested on a real natural gas. We show that our Raman gas analyzer prototype...

M. A. Buldakov; B. V. Korolev; I. I. Matrosov…

2013-03-01T23:59:59.000Z

120

Raman-resonant four-wave mixing and energy transfer  

Science Journals Connector (OSTI)

A common assumption that Raman-resonant four-wave mixing does not transfer energy between the light and the Raman medium is shown to be incorrect. The derivation of the correct...

Bobbs, Bradley; Warner, Charles

1990-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Real-TIme Raman Gas Composition Analyzer  

NLE Websites -- All DOE Office Websites (Extended Search)

Analyzer Analyzer Opportunity The Department of Energy's National Energy Technology Laboratory (NETL) is seeking collaborative research partners interested in implementing United States Provisional Patent Application entitled "Gas Sensing System Employing Raman Scattering". Disclosed in this application is a gas analyzing sensor that characterizes gaseous fuel, exhaust gases, or other process gas streams. The sensor reports concentrations of all majority gases at better than 0.3% accuracy in 1 second or less, and can be used for real-time gas analysis and system control. The sensor relies on novel techniques to enhance usually weak spontaneous Raman emissions from sample gases, enabling the application of Raman spectroscopy to rapid gas analysis. No commercially available sensor or sensing

122

Multistaged stokes injected Raman capillary waveguide amplifier  

DOE Patents (OSTI)

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.

Kurnit, Norman A. (Santa Fe, NM)

1980-01-01T23:59:59.000Z

123

Double resonance surface enhanced Raman scattering substrates: an intuitive coupled  

E-Print Network (OSTI)

. Westcott, L. R. Hirsch, J. L. West, and N. J. Halas, "Controlling the surface enhanced Raman effect via

124

Raman Spectrum of Graphene and Graphene Layers  

Science Journals Connector (OSTI)

Graphene is the two-dimensional building block for carbon allotropes of every other dimensionality. We show that its electronic structure is captured in its Raman spectrum that clearly evolves with the number of layers. The D peak second order changes in shape, width, and position for an increasing number of layers, reflecting the change in the electron bands via a double resonant Raman process. The G peak slightly down-shifts. This allows unambiguous, high-throughput, nondestructive identification of graphene layers, which is critically lacking in this emerging research area.

A. C. Ferrari; J. C. Meyer; V. Scardaci; C. Casiraghi; M. Lazzeri; F. Mauri; S. Piscanec; D. Jiang; K. S. Novoselov; S. Roth; A. K. Geim

2006-10-30T23:59:59.000Z

125

Transient Impulsive Giant Electronic Raman Redistribution  

E-Print Network (OSTI)

Resonant Raman excitation by ultrafast vacuum ultraviolet laser pulses is a powerful means to study electron dynamics in molecules, but experiments must contend with linear background ionization: frequencies high enough to reach resonant core-valence transitions will usually ionize all occupied orbitals as well, and the ionization cross sections are usually dominant. Here we show that attosecond pulses can induce a new process, transient impulsive stimulated Raman scattering, which can overwhelm valence ionization. Calculations are performed for atomic sodium, but the principal is valid for many molecular systems. This approach opens the path for high fidelity multidimensional spectroscopy with attosecond pulses.

Miyabe, S

2014-01-01T23:59:59.000Z

126

Raman approach in silicon nanostructure at 1.5 micron  

Science Journals Connector (OSTI)

In the last three years, the possibility of light generation and/or amplification in silicon, based on Raman emission, has achieved significant results. However, limitations inherent to the physics of silicon have been pointed out, too. In order to overcome ... Keywords: Raman amplifiers, Raman effect, nonlinear optics, porous silicon

L. Sirleto; M. A. Ferrara; B. Jalali; I. Rendina

2007-09-01T23:59:59.000Z

127

Vibrational Raman Spectroscopy of High-temperature Superconductors  

E-Print Network (OSTI)

Vibrational Raman Spectroscopy of High-temperature Superconductors C. Thomsen and G. Kaczmarczyk after the discovery of high- critical-temperature Tc superconductors:2 while reports on Raman scattering Wiley & Sons Ltd, Chichester, 2002 #12;Vibrational Raman Spectroscopy of High-temperature

Nabben, Reinhard

128

Special Section Guest Editorial Coherent Raman Imaging Techniques and Biomedical  

E-Print Network (OSTI)

Special Section Guest Editorial Coherent Raman Imaging Techniques and Biomedical Applications. The combination of high resolution and molecular contrast has moved Raman techniques into the biomedical spotlight on biomedical imag- ing. The spontaneous Raman interaction is weak, yielding insufficient photons for fast

Potma, Eric Olaf

129

Aurichalcite – An SEM and Raman spectroscopic study  

Science Journals Connector (OSTI)

Raman spectroscopy complimented with supplementary infrared spectroscopy has been used to characterise the vibrational spectrum of aurichalcite a zinc/copper hydroxy carbonate (Zn,Cu2+)5(CO3)2(OH)6. XRD patterns of all specimens show high orientation and indicate the presence of some impurities such as rosasite and hydrozincite. However, the diffraction patterns for all samples are well correlated to the standard reference patterns. SEM images show highly crystalline and ordered structures in the form of micron long fibres and plates. EDAX analyses indicate variations in chemical composition of Cu/Zn ratios ranging from 1/1.06 to 1/2.87. The symmetry of the carbonate anion in aurichalcite is Cs and is composition dependent. This symmetry reduction results in multiple bands in both the symmetric stretching and bending regions. The intense band at 1072 cm?1 is assigned to the ?1(CO3)2? symmetric stretching mode. Three Raman bands assigned to the ?3(CO3)2? antisymmetric stretching modes are observed for aurichalcite at 1506, 1485 and 1337 cm?1. Multiple Raman bands are observed in 800–850 cm?1 and 720–750 cm?1 regions and are attributed to ?2 and ?4 bending modes confirming the reduction of the carbonate anion symmetry in the aurichalcite structure. An intense Raman band at 1060 cm?1 is attributed to the ? OH deformation mode.

Ray L. Frost; Matt C. Hales; B. Jagannadha Reddy

2007-01-01T23:59:59.000Z

130

Rapid Research Note Raman Scattering in Resonance  

E-Print Network (OSTI)

-uniformity in the ternary alloy InGaN [4, 5]. However, resonance Raman scattering at bound excitons as reported for CdS doped 220 mm thick GaN film grown by hydride vapor phase epitaxy. Sapphire (0001) with a sputtered Zn

Nabben, Reinhard

131

Raman laser with controllable suppression of parasitics  

DOE Patents (OSTI)

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.

George, E. Victor (Livermore, CA)

1986-01-01T23:59:59.000Z

132

Deriving a Framework for Estimating Individual Tree Measurements with Lidar for Use in the TAMBEETLE Southern Pine Beetle Infestation Growth Model  

E-Print Network (OSTI)

. TAMBEETLE was used to compare spot growth between a lidar-derived forest map and a forest map generated by TAMBEETLE, based on sample plot characteristics. The lidar-derived forest performed comparably to the TAMBEETLE generated forest. Using lidar to map...

Stukey, Jared D.

2011-02-22T23:59:59.000Z

133

Progress Report on Frequency - Modulated Differential Absorption Lidar  

SciTech Connect

Modeling done at Pacific Northwest National Laboratory (PNNL) in FY2000 predicted improved sensitivity for remote chemical detection by differential absorption lidar (DIAL) if frequency-modulated (FM) lasers were used. This improved sensitivity results from faster averaging away of speckle noise and the recently developed quantum cascade (QC) lasers offer the first practical method for implementing this approach in the molecular fingerprint region of the infrared. To validate this model prediction, a simple laboratory bench FM-DIAL system was designed, assembled, tested, and laboratory-scale experiments were carried out during FY2001. Preliminary results of the FM DIAL experiments confirm the speckle averaging advantages predicted by the models. In addition, experiments were performed to explore the use of hybrid QC - CO2 lasers for achieving sufficient frequency-modulated laser power to enable field experiments at longer ranges (up to one kilometer or so). This approach will allow model validation at realistic ranges much sooner than would be possible if one had to first develop master oscillator - power amplifier systems utilizing only QC devices. Amplification of a QC laser with a CO2 laser was observed in the first hybrid laser experiments, but the low gain and narrow linewidth of the CO2 laser available for these experiments prevented production of a high-power FM laser beam.

Cannon, Bret D.; Harper, Warren W.; Myers, Tanya L.; Taubman, Matthew S.; Williams, Richard M.; Schultz, John F.

2001-12-15T23:59:59.000Z

134

Sensing Hadley cell with space-borne lidar  

Science Journals Connector (OSTI)

Abstract Some recent studies reported expansion of the Earth?s tropical regime in the past few decades. The poleward expansion of the Hadley cell is a strong indication of the warming of the globe. The extent of Hadley cell also has very important implications to the climate of dry subtropical regions because of the prevalence of precipitation in the deep tropical belt. Determination of the Hadley circulation especially its extent has great significance for monitoring global climate change and for the subtropical climate studies. Although many methods have been developed in recent years, reliable measurement of the extent of Hadley cell is still an issue in climate studies. This letter shows that the extent of the Hadley cell could reliably be estimated by measuring the height of the uppermost super-thin clouds in the troposphere with space-borne lidar. Through consecutive multi-year measurements of the height of the uppermost super-thin clouds, a good estimation of the expansion of the Hadley cell could be obtained.

Wenbo Sun; Bing Lin; Rosemary R. Baize; Gorden Videen; Yongxiang Hu

2014-01-01T23:59:59.000Z

135

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

Open Energy Info (EERE)

Nine Palms Area (Sabin, Et Al., 2010) Nine Palms Area (Sabin, Et Al., 2010) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: LiDAR At Twenty-Nine Palms Geothermal Area (Sabin, Et Al., 2010) Exploration Activity Details Location Twenty-Nine Palms Geothermal Area Exploration Technique LiDAR Activity Date Usefulness useful DOE-funding Unknown Notes As previously mentioned, a deep slim hole is scheduled to be drilled in the Camp Wilson area of MCAGCC in June, 2010. The location of this hole is entirely driven by favorable structures as interpreted from LiDAR data and results of the Seabee TGH drilling program completed in early 2009. Details of the MCAGCC work are available in another section of this volume. References Andrew Sabin, S. Bjornstad, M. Lazaro, D. Meade, C. Page, S. Alm, A.

136

Structural Analysis of Southern Dixie Valley using LiDAR and Low-Sun-Angle  

Open Energy Info (EERE)

Structural Analysis of Southern Dixie Valley using LiDAR and Low-Sun-Angle Structural Analysis of Southern Dixie Valley using LiDAR and Low-Sun-Angle Aerial Photography, NAS Fallon Geothermal Exploration Project, Dixie Valley, Nevada Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Structural Analysis of Southern Dixie Valley using LiDAR and Low-Sun-Angle Aerial Photography, NAS Fallon Geothermal Exploration Project, Dixie Valley, Nevada Abstract The goal of this study is to map and characterize Quaternary faults in southern Dixie Valley for the Department of the Navy Geothermal Program Office's NAS Fallon Geothermal Exploration Project. We will use this information to better characterize the regional structure and geothermal resource potential of the area,with a focus on determining the structural

137

A Comparison of Cirrus Cloud Visible Optical Depth Derived from Lidar  

NLE Websites -- All DOE Office Websites (Extended Search)

Comparison of Cirrus Cloud Visible Optical Depth Derived from Lidar Comparison of Cirrus Cloud Visible Optical Depth Derived from Lidar Lo, Chaomei Pacific Northwest National Laboratory Comstock, Jennifer Pacific Northwest National Laboratory Flynn, Connor Pacific Northwest National Laboratory Category: Cloud Properties Optically thin clouds (e.g. optical depth < 3) can have a significant impact on radiative heating in the atmosphere, particularly in the cold upper troposphere. Currently, there is no value-added product (VAP) in the Atmospheric Radiation Measurement (ARM) program archive that produces thin cloud optical depth, particularly at the Tropical Western Pacific and North Slope of Alaska sites. A VAP is under development to obtain the cirrus cloud visible optical depth from the MPLNOR (Micro Pulse Lidar Normalized

138

Correlated excitations and Raman scattering in glasses  

Science Journals Connector (OSTI)

The dominant Raman line in AX2 tetrahedral glasses is demonstrated to be caused by correlated symmetric stretch motions of the bridging X atoms. Using a bond-polarizability model and the central-force model of Sen and Thorpe, we derive simple analytic forms for Raman spectra. We show that correlations may cause qualitative changes in the polarized spectrum leading to a peak at the edge of a band of vibrational states, whereas the depolarized spectrum is less affected and mimics the density of states. Both features are clearly observed in GeO2 and explain features in many other glasses. The same reasoning leads to a prediction of unusual spectral features in electronic spectra of disordered solids which may be observable in angular-dependent photoemission.

Richard M. Martin and Frank L. Galeener

1981-03-15T23:59:59.000Z

139

Raman spectroscopy study of selected uranophanes  

Science Journals Connector (OSTI)

Raman spectra at 298 and 77 K of three uranophane samples from different localities are described and interpreted. The spectra are sample dependent. U–O bond lengths in uranyls are calculated from the spectra and compared with the published data of single crystal structure and EXAFS spectroscopy. Hydrogen-bonding of water molecules and silanols is discussed and the ‘proton mobility’ in uranophane sheet crystal structure is assumed.

Ray L. Frost; Ji?í ?ejka; Matt L. Weier; Wayde N. Martens

2006-01-01T23:59:59.000Z

140

High-Speed Coherent Raman Fingerprint Imaging of Biological Tissues  

E-Print Network (OSTI)

We have developed a coherent Raman imaging platform using broadband coherent anti-Stokes Raman scattering (BCARS) that provides an unprecedented combination of speed, sensitivity, and spectral breadth. The system utilizes a unique configuration of laser sources that probes the Raman spectrum over 3,000 cm$^{-1}$ and generates an especially strong response in the typically weak Raman "fingerprint" region through heterodyne amplification of the anti-Stokes photons with a large nonresonant background (NRB) while maintaining high spectral resolution of $chemical imaging in two- and three-dimensional views of healthy murine liver and pancreas tissues and interfaces between xenograft brain tumors and the surrounding healthy brain matter.

Camp, Charles H; Heddleston, John M; Hartshorn, Christopher M; Walker, Angela R Hight; Rich, Jeremy N; Lathia, Justin D; Cicerone, Marcus T

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Graphene and its derivatives : fabrication and Raman spectroscopy study.  

E-Print Network (OSTI)

??This thesis presents results on fabrication and Raman spectroscopy studies of graphene and its derivates. The works can be divided into two parts as follows.… (more)

Cong, Chunxiao.

2012-01-01T23:59:59.000Z

142

A Four-Year Lidar–Sun Photometer Aerosol Study at São Paulo, Brazil  

Science Journals Connector (OSTI)

A backscattering lidar system, the first of this kind in Brazil, has been used to provide the vertical profile of the aerosol backscatter coefficient at 532 nm up to an altitude of 4–6 km above sea level (ASL), in a suburban area in the city of ...

Eduardo Landulfo; Alexandros Papayannis; Ani Sobral Torres; Sandro Toshio Uehara; Lucila Maria Viola Pozzetti; Caio Alencar de Matos; Patricia Sawamura; Walter Morinobu Nakaema; Wellington de Jesus

2008-08-01T23:59:59.000Z

143

A geometric framework for channel network extraction from lidar: Nonlinear diffusion and geodesic paths  

E-Print Network (OSTI)

A geometric framework for channel network extraction from lidar: Nonlinear diffusion and geodesic extraction. Following this preprocessing, channels are defined as curves of minimal effort, or geodesics and geodesic paths, J. Geophys. Res., 115, F01002, doi:10.1029/2009JF001254. 1. Introduction [2] The detection

Foufoula-Georgiou, Efi

144

AUTOMATED MODELING OF 3D BUILDING ROOFS USING IMAGE AND LIDAR DATA  

E-Print Network (OSTI)

AUTOMATED MODELING OF 3D BUILDING ROOFS USING IMAGE AND LIDAR DATA N. Demir* , E. Baltsavias, Detection, 3D Modelling ABSTRACT: In this work, an automated approach for 3D building roof modelling on the 3D building roof modelling. Buildings have a critical role for 3D city models, decision support

Schindler, Konrad

145

Measuring forest structure and biomass in New England forest stands using Echidna ground-based lidar  

E-Print Network (OSTI)

Measuring forest structure and biomass in New England forest stands using Echidna ground Accepted 12 March 2010 Available online 14 May 2011 Keywords: Ground-based lidar Forest structure Biomass biomass with very good accuracy in six New England hardwood and conifer forest stands. Comparing forest

Ni-Meister, Wenge

146

Master thesis: "Validation of wake-simulation models based on long-range lidar measurements."  

E-Print Network (OSTI)

Figure 1: Simulation of lidar measurements in the wake of a wind turbine using a LES generated wind field mapping and wake/vortex detection in several research projects and airport applications. At ForWind resolution wind data from the inflow and wake of two multi-megawatt wind energy converters. Possible

Peinke, Joachim

147

LIDAR measurements of wind turbine wake dyn_amics and comparison with an engineering model  

E-Print Network (OSTI)

LIDAR measurements of wind turbine wake dyn_amics and comparison with an engineering model 1 dynamics, lIre performed at four diameters behind a 95 kW wind turbine. The wake 111eaeasurement technique allows esti111ation of qUClsiinstantancou~ two dimensional wind fields in an area

148

USING LIDAR TO MEASURE PERFLUOROCARBON TRACERS FOR THE VERIFICATION AND MONITORING  

E-Print Network (OSTI)

USING LIDAR TO MEASURE PERFLUOROCARBON TRACERS FOR THE VERIFICATION AND MONITORING OF CAP AND COVER to detect PMCH (perfluoromethylcyclohexane, one of a group of PFTs used at BNL). Laboratory measurements then measured down to 1 ppb-m. These results are very promising and show great potential for monitoring

149

Fusion of 3D-LIDAR and camera data for scene parsing  

Science Journals Connector (OSTI)

Fusion of information gathered from multiple sources is essential to build a comprehensive situation picture for autonomous ground vehicles. In this paper, an approach which performs scene parsing and data fusion for a 3D-LIDAR scanner (Velodyne HDL-64E) ... Keywords: Camera, Fuzzy logic, MRF, Object detection, RGBD, Scene parsing, Temporal fusion, Velodyne scanner

Gangqiang Zhao; Xuhong Xiao; Junsong Yuan; Gee Wah Ng

2014-01-01T23:59:59.000Z

150

Biomass and Bioenergy 31 (2007) 646655 Estimating biomass of individual pine trees using airborne lidar  

E-Print Network (OSTI)

Biomass and Bioenergy 31 (2007) 646­655 Estimating biomass of individual pine trees using airborne biomass and bio-energy feedstocks. The overall goal of this study was to develop a method for assessing aboveground biomass and component biomass for individual trees using airborne lidar data in forest settings

151

Using LIDAR in Highway Rock Cuts Norbert H. Maerz, Ph. D., P. Eng,  

E-Print Network (OSTI)

the data needed to begin the process of modeling the rock raveling process. INTRODUCTION LIDAR damage, injury, and even death. Highways impeded by even small spills of rock material by blasting techniques to facilitate the highway construction. A constant danger to the motoring public

Maerz, Norbert H.

152

LIDAR-BASED VEHICLE TRACKING FOR STOPPING DISTANCE MEASUREMENT AT INTERSECTIONS  

E-Print Network (OSTI)

] are currently the most commonly used system to detect vehicle and measure velocities at a fixed site of a Light Detection and Ranging (LIDAR) sensor to accurately track a vehicle as it passes through to traffic laws. Driver warning systems can increase vehicle safety, especially near accident

Brennan, Sean

153

Linking imaging spectroscopy and LiDAR with floristic composition and forest structure in Panama  

Science Journals Connector (OSTI)

Abstract Landsat and Shuttle Radar Topography Mission (SRTM) imagery have recently been used to identify broad-scale floristic units in Neotropical rain forests, corresponding to geological formations and their edaphic properties. Little is known about the structural and functional variation between these floristic units, however, and Landsat and SRTM data lack the spectral and spatial resolution needed to provide this information. Imaging spectroscopy and LiDAR (Light Detection and Ranging) have been used to measure canopy structure and function in a variety of ecosystems, but the ability of these technologies to measure differences between compositionally-distinct but otherwise uniform tropical forest types remains unknown. We combined 16 tree inventories from central Panama with imaging spectroscopy and LiDAR elevation data from the Carnegie Airborne Observatory to test our ability to identify patterns in plant species composition, and to measure the spectral and structural differences between adjacent closed-canopy tropical forest types. We found that variations in spectroscopic imagery and LiDAR data were strong predictors of spatial turnover in plant species composition. We also found that these compositional, chemical, and structural patterns corresponded to underlying geological formations and their geomorphological properties. We conclude that imaging spectroscopy and LiDAR data can be used to interpret patterns identified in lower resolution sensors, to provide new information on forest function and structure, and to identify underlying determinants of these patterns.

Mark A. Higgins; Gregory P. Asner; Roberta E. Martin; David E. Knapp; Christopher Anderson; Ty Kennedy-Bowdoin; Roni Saenz; Antonio Aguilar; S. Joseph Wright

2014-01-01T23:59:59.000Z

154

Improved forecasts of extreme weather events by future space borne Doppler wind lidar  

E-Print Network (OSTI)

sensitive areas. To answer these questions simulation experiments with state-of-the-art numerical weather prediction (NWP) models have proved great value to test future meteorological observing systems a prioriImproved forecasts of extreme weather events by future space borne Doppler wind lidar Gert

Marseille, Gert-Jan

155

Master Thesis: Dual-Doppler technique applied to scanning lidars for the characterization of  

E-Print Network (OSTI)

and wind turbine wakes in large wind farms offshore. Wind Energy, 12(5):431­444, 2009. [2] Brian Hirth, D of single wind turbines for the validation or tuning of wake models [1]. Recent full-field campaigns showed-lidar system was developed and installed at the offshore wind farm "alpha ventus". This system includes three

Peinke, Joachim

156

Metal uorescence lidar (light detection and ranging) and the middle atmosphere  

E-Print Network (OSTI)

lidar takes advantage of the naturally occurring sodium atoms between 80 and 110 km above sea level (the though it is exposed to constant solar radiation. The hope of explaining a region strongly coupled as the `-pause' of the layer below them (see ®gure 1). Radiative absorption and emission are dominating eects

157

Lidars in Wind Energy Jakob Mann, Ferhat Bingl, Torben Mikkelsen, Ioannis Antoniou, Mike  

E-Print Network (OSTI)

Lidars in Wind Energy Jakob Mann, Ferhat Bingöl, Torben Mikkelsen, Ioannis Antoniou, Mike Courtney, Gunner Larsen, Ebba Dellwik Juan Jose Trujillo* and Hans E. Jørgensen Wind Energy Department Risø of the presentation · Introduction to wind energy · Accurate profiles of the mean wind speed · Wakes behind turbines

158

Simultaneous radar and lidar cloud measurements at Geesthacht (53.5°N, 10.5°E)  

Science Journals Connector (OSTI)

Comparisons have been made of the cloud profiles obtained from the backscatter signals of a 95-GHz radar and a 720-nm lidar system between 23 May and 4 November 1997 at Geesthacht (53°24? N, 10°26? E). Although the wavelengths of the two systems differ by a factor of 4 000, remarkably similar data have been obtained in many cases. There are differences, though. Small droplets do not interact significantly with the radar pulses, and hence can only be seen by the lidar due to their strong scattering in the UV/VIS. On the other hand, attenuation of the lidar pulses by underlying clouds and gas absorbers makes upper cloud regions and especially cloud top heights better detectable for the radar. Rain and snow falling out of a cloud and evaporating on the way down cannot be distinguished from the cloud region by the radar, but a fast downward component in the Doppler spectrum is indicative of precipitation in or under a cloud. For quantitative cloud studies collocated radar-lidar systems considerably add to the experimental capabilities of each of the two systems alone.

C. Weitkamp; H. Flint; W. Lahmann; F.A. Theopold; O. Danne; M. Quante; E. Raschke

1999-01-01T23:59:59.000Z

159

E-Print Network 3.0 - anti-stokes raman spectroscopic Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

a coherent anti-Stokes Raman spectroscopic imaging device in which two laser pulse trains... . August 19, 2008 System and method for coherent anti-Stokes Raman scattering...

160

E-Print Network 3.0 - adeep-ultraviolet resonance raman Sample...  

NLE Websites -- All DOE Office Websites (Extended Search)

Maruyama Summary: Temperature dependence of resonance Raman of single-walled carbon nanotubes Shohei Chiashi... , Mototeru Oba and Shigeo Maruyama Raman scattering from...

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

MODIFYING AN INVERTED LABORATORY MICROSCOPE FOR RAMAN Presented in Partial Fulfillment of the Requirements for  

E-Print Network (OSTI)

MODIFYING AN INVERTED LABORATORY MICROSCOPE FOR RAMAN MICROSCOPY A Thesis Presented in Partial modifications a spectroscopic imaging instrument, a Raman microscope, can be constructed from a common inverted

162

Raman Spectroscopy and Genetic Algorithms for the Classification of Wood Types  

Science Journals Connector (OSTI)

Raman spectroscopy and pattern recognition techniques are used to develop a potential method to characterize wood by type. The test data consists of 98 Raman spectra of temperate...

Lavine, B K; Davidson, C E; Moores, A J; Griffiths, P R

2001-01-01T23:59:59.000Z

163

Quantum-entanglement-initiated super Raman scattering  

SciTech Connect

It has now been possible to prepare a chain of ions in an entangled state and thus the question arises: How will the optical properties of a chain of entangled ions differ from say a chain of independent particles? We investigate nonlinear optical processes in such chains. Since light scattering is quite a versatile technique to probe matter, we explicitly demonstrate the possibility of entanglement-produced super Raman scattering. Our results suggest the possibility of similar enhancement factors in other nonlinear processes like four-wave mixing.

Agarwal, G. S. [Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)

2011-02-15T23:59:59.000Z

164

Optical pumping via incoherent Raman transitions  

E-Print Network (OSTI)

A new optical pumping scheme is presented that uses incoherent Raman transitions to prepare a trapped Cesium atom in a specific Zeeman state within the 6S_{1/2}, F=3 hyperfine manifold. An important advantage of this scheme over existing optical pumping schemes is that the atom can be prepared in any of the F=3 Zeeman states. We demonstrate the scheme in the context of cavity quantum electrodynamics, but the technique is equally applicable to a wide variety of atomic systems with hyperfine ground-state structure.

A. D. Boozer; R. Miller; T. E. Northup; A. Boca; H. J. Kimble

2007-10-04T23:59:59.000Z

165

Raman Measurements on Electrochemically Doped Single-Walled Carbon Nanotubes  

E-Print Network (OSTI)

Raman Measurements on Electrochemically Doped Single-Walled Carbon Nanotubes P. M. Rafailov, M and studied the Raman response of electro- chemically doped single-walled carbon nanotubes (SWNT) using different salt solutions. The fre- quency shift of the radial breathing mode (RBM) and the high-energy mode

Nabben, Reinhard

166

Shell-isolated nanoparticle-enhanced Raman spectroscopy  

E-Print Network (OSTI)

LETTERS Shell-isolated nanoparticle-enhanced Raman spectroscopy Jian Feng Li1 , Yi Fan Huang1 or in the form of nanoparticles, are required to realise a substantial SERS effect, and this has severely limited, we report an approach, which we name shell-isolated nanoparticle-enhanced Raman spectro- scopy

La Rosa, Andres H.

167

Hydrogen Raman shifts in carbon nanotubes from molecular dynamics simulation  

E-Print Network (OSTI)

Hydrogen Raman shifts in carbon nanotubes from molecular dynamics simulation S.J.V. Frankland *, D hydrogen in individual single-shell carbon nanotubes and nanotube ropes using a semiclassical model. The calculations predict that isolated hydrogen molecules inside of nanotubes have a Raman frequency that increases

Brenner, Donald W.

168

Estimating forest structural characteristics with airborne lidar scanning and a near-real time profiling laser systems  

E-Print Network (OSTI)

LiDAR (Light Detection and Ranging) directly measures canopy vertical structures, and provides an effective remote sensing solution to accurate and spatiallyexplicit mapping of forest characteristics, such as canopy height and Leaf Area Index...

Zhao, Kaiguang

2009-05-15T23:59:59.000Z

169

Use of LiDAR to estimate stand characteristics for thinning operations in young Douglas-fir plantations  

Science Journals Connector (OSTI)

Light Detection and Ranging (LiDAR) has been successfully used to describe a wide range of forest metrics at local, regional and national scales. However, little research has used this technology in young Doug...

Michael S Watt; Andrew Meredith; Pete Watt…

2013-12-01T23:59:59.000Z

170

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

DOE Patents (OSTI)

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.

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

2006-06-20T23:59:59.000Z

171

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

SciTech Connect

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.

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

2014-11-01T23:59:59.000Z

172

HiRes camera and LIDAR ranging system for the Clementine mission  

SciTech Connect

Lawrence Livermore National Laboratory developed a space-qualified High Resolution (HiRes) imaging LIDAR (Light Detection And Ranging) system for use on the DoD Clementine mission. The Clementine mission provided more than 1.7 million images of the moon, earth, and stars, including the first ever complete systematic surface mapping of the moon from the ultra-violet to near-infrared spectral regions. This article describes the Clementine HiRes/LIDAR system, discusses design goals and preliminary estimates of on-orbit performance, and summarizes lessons learned in building and using the sensor. The LIDAR receiver system consists of a High Resolution (HiRes) imaging channel which incorporates an intensified multi-spectral visible camera combined with a Laser ranging channel which uses an avalanche photo-diode for laser pulse detection and timing. The receiver was bore sighted to a light-weight McDonnell-Douglas diode-pumped ND:YAG laser transmitter that emmitted 1.06 {micro}m wavelength pulses of 200 mJ/pulse and 10 ns pulse-width, The LIDAR receiver uses a common F/9.5 Cassegrain telescope assembly. The optical path of the telescope is split using a color-separating beamsplitter. The imaging channel incorporates a filter wheel assembly which spectrally selects the light which is imaged onto a custom 12 mm gated image intensifier fiber-optically-coupled into a 384 x 276 pixel frame transfer CCD FPA. The image intensifier was spectrally sensitive over the 0.4 to 0.8 {micro}m wavelength region. The six-position filter wheel contained 4 narrow spectral filters, one broadband and one blocking filter. At periselene (400 km) the HiRes/LIDAR imaged a 2.8 km swath width at 20-meter resolution. The LIDAR function detected differential signal return with a 40-meter range accuracy, with a maximum range capability of 640 km, limited by the bit counter in the range return counting clock.

Ledebuhr, A.G.; Kordas, J.F.; Lewis, I.T. [and others

1995-04-01T23:59:59.000Z

173

ARM - Field Campaign - NASA Coordinated Airborne CO2 Lidar Flight Test  

NLE Websites -- All DOE Office Websites (Extended Search)

govCampaignsNASA Coordinated Airborne CO2 Lidar Flight Test Campaign govCampaignsNASA Coordinated Airborne CO2 Lidar Flight Test Campaign Comments? We would love to hear from you! Send us a note below or call us at 1-888-ARM-DATA. Send Campaign : NASA Coordinated Airborne CO2 Lidar Flight Test Campaign 2009.07.27 - 2009.08.07 Lead Scientist : Edward Browell For data sets, see below. Description This airborne field test campaign was designed to obtain a coordinated set of remote CO2 Laser Absorption Spectrometer (LAS) measurements using the NASA Langley/ITT 1.57-micron Continuous-Wave (CW) LAS operating from the NASA Langley UC-12 aircraft; the NASA Goddard 1.57-micron pulsed LAS operating from the NASA Glenn Lear-25 aircraft; and the NASA Jet Propulsion Laboratory 2.0-micron CW-coherent LAS operating from a contracted Twin Otter aircraft. These remote LAS CO2 column measurements were compared with

174

Measurement of Gas Hydrate by Laser Raman Spectrometry  

Science Journals Connector (OSTI)

Four types of natural sand (respectively 250–350, 180–250, 125 ... ) are used as media to synthesize methane hydrate that is measured by laser Raman spectrometry. ... show that sediment grain sizes do not influen...

Changling Liu; Qingguo Meng; Yuguang Ye

2013-01-01T23:59:59.000Z

175

Detection of Physiologically Relevant Alcohol Concentrations Using Raman Spectroscopy  

E-Print Network (OSTI)

This is the first step in a series of studies to test the feasibility of using Raman Spectroscopy (RS) to non-invasively detect physiologically relevant blood alcohol concentrations. Blood tests, urine tests, and the breathalyzer are currently...

McKay, Joshua L.

2006-08-16T23:59:59.000Z

176

Quantitative biological Raman spectroscopy for non-invasive blood analysis  

E-Print Network (OSTI)

The long term goal of this project is the measurement of clinically-relevant analytes in the blood tissue matrix of human subjects using near-infrared Raman spectroscopy, with the shorter term research directed towards ...

Shih, Wei-Chuan

2007-01-01T23:59:59.000Z

177

High conversion efficiency ultraviolet fiber Raman oscillator--amplifier system  

SciTech Connect

High efficiency UV frequency conversion by stimulated Raman scattering in a XeCl (lambda = 308-nm) excimer laser-pumped multimode fiber is presented. The system consists of a first piece of fiber as a Stokes generator and a second as a power amplifier. Power conversion efficiencies up to 80% have been measured. Uses of fiber Raman amplifiers in the near UV are also discussed.

Pini, R.; Salimbeni, R.; Vannini, M.; Haider, A.F.M.Y.; Lin, C.

1986-04-01T23:59:59.000Z

178

Surface-Enhanced Raman Scattering (SERS) and Surface-Enhanced Resonance Raman Scattering (SERRS) on HNO3-Roughened Copper Foil  

Science Journals Connector (OSTI)

Copper foils for a Raman study were prepared by a chemical etching method with HNO3. These foils were found to exhibit a strong SERS effect, SERS or SERRS spectra of...

Xue, Gi; Dong, Jian; Zhang, Mingsheng

1991-01-01T23:59:59.000Z

179

Predicted intensities for new Raman transitions in solid HD  

Science Journals Connector (OSTI)

The scattering efficiencies for the zero-phonon and phonon branches associated with predicted new Raman transitions in solid HD are calculated. These transitions arise from the interaction-induced polarizability of a pair of molecules expressed in terms of the vector separation between the centers of mass and satisfy different rotational selection rules from those of allowed Raman transitions. For single transitions in which only one molecule of the pair is excited by the incoming photon, one expects an R branch, while, for double transitions in which both molecules are excited, one expects R+S and T+S branches with progressively less intensity. A previously obtained experimental Raman spectrum of solid HD does have spectral features similar in shape and intensity to those predicted for the RR phonon branch, although this feature was tentatively assigned as a two-phonon Raman-active transition. We conclude that a new Raman study of solid HD carried out with higher sensitivity and over a greater frequency region would be of interest to determine the correct assignment of this feature and to look for other predicted transitions resulting from the interaction-induced polarizability.

M. Attia; M. Ali; R. H. Tipping; J. D. Poll

1989-11-01T23:59:59.000Z

180

Measurement of Petroleum Fuel Contamination in Water by Solid-Phase Microextraction with Direct Raman Spectroscopic Detection  

Science Journals Connector (OSTI)

A method is described for determining petroleum fuel contamination in water based on solid-phase microextraction and Raman spectroscopy (SPME/Raman). In this method, contaminants are...

Jager, Michael J; McClintic, Daniel P; Tilotta, David C

2000-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

The application of surface-enhanced Raman spectroscopy for the detection of excitatory amino acids  

E-Print Network (OSTI)

enhanced Raman spectroscopy (SERS) on aqueous silver colloids. This study examines methods to monitor the colloidal reactions for the calibration of the enhancement observed. Thirty second Raman spectral scans were taken utilizing a 50 mW argon laser...

O'Neal, Dennis Patrick Doucet

1999-01-01T23:59:59.000Z

182

G? band in double- and triple-walled carbon nanotubes: A Raman study  

E-Print Network (OSTI)

Double- and triple-walled carbon nanotubes are studied in detail by laser energy-dependent Raman spectroscopy in order to get a deeper understanding about the second-order G[superscript '] band Raman process, general ...

Hirschmann, Thomas Ch.

183

Competition between stimulated Raman and Brillouin scattering processes in CF4 gas  

Science Journals Connector (OSTI)

CF4 gas has a relatively high Raman cross section and a relatively small Raman shift and is an excellent candidate for a gas-filled hollow-core photonic bandgap (HC-PBG)...

Yehud, Lior Ben; Belker, Daniel; Ravnitzki, Gad; Ishaaya, Amiel A

2014-01-01T23:59:59.000Z

184

Noise figure and photon statistics in coherent anti-Stokes Raman scattering  

E-Print Network (OSTI)

). 11. J. Perina, "Photon statistics in Raman scattering with frequency mismatch," Optica Acta 28, 1529 (1981). 12. J. Perina, "Photon statistics in Raman scattering of intense coherent light," Optica Acta 28

Jalali. Bahram

185

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

DOE Patents (OSTI)

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.

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

2014-07-22T23:59:59.000Z

186

Raman spectroscopy of the components of 18th-century icon painting  

Science Journals Connector (OSTI)

The method of Raman spectroscopy is employed in the analysis of lead-containing pigments in ancient Russian painting, transformed pigments, chalk, and drying oil. The Raman spectra of white lead and the mixture o...

N. N. Brandt; N. L. Rebrikova; A. Yu. Chikishev

2009-12-01T23:59:59.000Z

187

Optical Coherence Tomography and Raman Spectroscopy of the retina  

SciTech Connect

Imaging the structure and correlating it with the biochemical content of the retina holds promise for fundamental research and for clinical applications. Optical coherence tomography (OCT) is commonly used to image the 3D structure of the retina and while the added functionality of biochemical analysis afforded by Raman scattering could provide critical molecular signatures for clinicians and researchers, there are many technical challenges to combining these imaging modalities. We present an ex vivo OCT microscope combined with Raman spectroscopy capable of collecting morphological and molecular information about a sample simultaneously. The combined instrument will be used to investigate remaining technical challenges to combine these imaging modalities, such as the laser power levels needed to achieve a Raman signal above the noise level without damaging the sample.

Evans, J W; Zawadzki, R J; Liu, R; Chan, J; Lane, S; Werner, J S

2009-01-16T23:59:59.000Z

188

UV resonance Raman analysis of trishomocubane and diamondoid dimers  

SciTech Connect

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 2.33 eV and 5.42 eV. 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.

Meinke, Reinhard, E-mail: rene@physik.tu-berlin.de; Thomsen, Christian; Maultzsch, Janina [Institut für Festkörperphysik, Technische Universität Berlin, Hardenbergstr. 36, D-10623 Berlin (Germany)] [Institut für Festkörperphysik, Technische Universität Berlin, Hardenbergstr. 36, D-10623 Berlin (Germany); Richter, Robert; Merli, Andrea [Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstr. 36, D-10623 Berlin (Germany)] [Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstr. 36, D-10623 Berlin (Germany); Fokin, Andrey A. [Institute of Organic Chemistry, Justus-Liebig University, Heinrich-Buff-Ring 58, D-35392 Giessen (Germany) [Institute of Organic Chemistry, Justus-Liebig University, Heinrich-Buff-Ring 58, D-35392 Giessen (Germany); Department of Organic Chemistry, Kiev Polytechnic Institute, pr. Pobedy 37, 03056 Kiev (Ukraine); Koso, Tetyana V.; Schreiner, Peter R. [Institute of Organic Chemistry, Justus-Liebig University, Heinrich-Buff-Ring 58, D-35392 Giessen (Germany)] [Institute of Organic Chemistry, Justus-Liebig University, Heinrich-Buff-Ring 58, D-35392 Giessen (Germany); Rodionov, Vladimir N. [Department of Organic Chemistry, Kiev Polytechnic Institute, pr. Pobedy 37, 03056 Kiev (Ukraine)] [Department of Organic Chemistry, Kiev Polytechnic Institute, pr. Pobedy 37, 03056 Kiev (Ukraine)

2014-01-21T23:59:59.000Z

189

Raman fibre lasers based on heavily GeO{sub 2}-doped fibres  

SciTech Connect

Amplification of radiation due to stimulated Raman scattering in an optical fibre with a heavily GeO{sub 2}-doped core and a fused silica cladding is studied. The applications of such fibres in Raman lasers are demonstrated. A Raman fibre laser emitting 10 W at a fibre length of only 3 m and Raman lasers emitting at 1.73, 1.85, 2.06, and 2.2 {mu}m are fabricated for the first time. (fibre lasers)

Dianov, Evgenii M; Bufetov, Igor' A; Mashinsky, V M; Shubin, Aleksei V; Medvedkov, O I; Rakitin, A E; Mel'kumov, Mikhail A [Fiber Optics Research Center, Russian Academy of Sciences, Moscow (Russian Federation); Khopin, V F; Gur'yanov, A N [Institute of Chemistry of High-Purity Substances, Russian Academy of Sciences, Nizhnii Novgorod (Russian Federation)

2005-05-31T23:59:59.000Z

190

Summary report of FY 1995 Raman spectroscopy technology development  

SciTech Connect

US DOE is sponsoring development of remote, fiber-optic Raman spectroscopy for rapid chemical characterization of Hanford high-level radioactive tank waste. Deployment targets for this technology are analytical hot cells and, via the Light-Duty Utility Arm and cone penetrometer, the waste tanks themselves. Perceived benefits of fiber-optic Raman spectroscopy are (1) rapid generation of tank-waste safety-related data, (2) reduced personnel exposure to highly radioactive waste, (3) reduced tank-waste sampling and analysis costs, and (4) reduced radioactive analytical waste. This document presents the results from the investigation of two dispersive, transmission-grating Raman systems and four fiber-optic Raman probe designs with non-radioactive tank waste simulants. One Raman system used a 532-nm, 400 mW, solid-state laser; the other used a 785-nm, 500 mW, solid-state diode laser. We found (1) the transmission-grating systems had better wavelength stability than previously tried Czerny-Turner-Based systems and (2) the 785-nm system`s specie detection limits in the spectral fingerprint regiion were at least as good as those for the 532-nm system. Based on these results, and the fact that some tank wastes luminesce with 514.5nm excitation, we selected the 785-nm system for hot-cell use. Of the four probes tested, three had a ``six-around-on`` fiber probe design; the fourth probe was a one-fiber-in-one-fiber-out, diffuse-relectance design. Comparison of the four probes` signal-to-noise rations, rations, transmission/collection efficiencies, and probe-silica Raman backgrounds showed that the best probe for use with Hanford-Site tank waste should (1) be filtered as close to the probe tip as possible to reduce the probe-silica Raman background and (2) have multiple collection fibers. The responses of all the probes tested showed a strong dependence on probe-sample distance, and the presence of a probe window appeared to increase the probe`s silica Raman background.

Douglas, J.G.

1995-11-01T23:59:59.000Z

191

Infrared divergence of the resonant Raman-Compton scattering  

Science Journals Connector (OSTI)

The infrared divergence of the resonant Raman-Compton scattering has been studied in collisions of photons on atomic L electrons in the intermediate-momentum-transfer regime. Low-energy continua emitted by Zr atoms, excited, in the vicinity of the K edge, by the monochromatized x rays delivered by the LURE Synchrotron Radiation Facility, have been observed on vary thin targets and compared with the theoretically predicted infrared divergence of the Raman scattering. The characteristic change in shape of these continua has been studied on a wide energy range below the Zr K edge.

J. P. Briand; A. Simionovici; P. Chevallier; P. Indelicato

1989-05-01T23:59:59.000Z

192

Raman scattering in carbon nanotubes revisited J. Maultzsch, S. Reich, and C. Thomsen  

E-Print Network (OSTI)

of whether the high-energy Raman spectrum in carbon nanotubes is also dominated by processes that allow for understanding the high-energy modes in carbon nanotubes attribute the ob- served Raman peaks to -pointRaman scattering in carbon nanotubes revisited J. Maultzsch, S. Reich, and C. Thomsen Institut fu

Nabben, Reinhard

193

Variable temperature Raman microscopy as a nanometrology tool for graphene layers and graphene-based devices  

E-Print Network (OSTI)

Variable temperature Raman microscopy as a nanometrology tool for graphene layers and graphene; accepted 24 July 2007; published online 15 August 2007 Raman microscopy of graphene was carried out over-band frequencies extracted from Raman spectra of the single-layer graphene are - 1.6±0.2 10-2 cm-1 /K and - 3

194

Raman response of magnetic excitations in cuprate ladders and planes K. P. Schmidt*  

E-Print Network (OSTI)

by inelastic neutron scattering,10­14 the quantitative un- derstanding of the two-magnon line shape is heavily debated. Two-magnon Raman scattering has been proven to be a powerful tool to study quantum as two-triplon Raman scattering. On the one hand, one may expect that the Raman re- sponse is dominated

Nabben, Reinhard

195

Modeling LIDAR Detection of Biological Aerosols to Determine Optimum Implementation Strategy  

SciTech Connect

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.

Sheen, David M.; Aker, Pam M.

2007-09-19T23:59:59.000Z

196

Lidar Investigation of Tropical Nocturnal Boundary Layer Aerosols and Cloud Macrophysics  

SciTech Connect

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.

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

2013-10-01T23:59:59.000Z

197

A comparison of cloud top heights computed from airborne lidar and MAS radiance data using CO2 slicing  

E-Print Network (OSTI)

A comparison of cloud top heights computed from airborne lidar and MAS radiance data using CO2 in assessing the accuracy of the CO2-slicing cloud height algorithm. Infrared measurements of upwelling which included various single- layer and multilayer cloud conditions. Overall, the CO2-slicing method

Sheridan, Jennifer

198

SIMULTANEOUS AND COMMON-VOLUME LIDAR OBSERVATIONS OF THE MESOSPHERIC FE AND NA LAYERS AT BOULDER (40N, 105W)  

E-Print Network (OSTI)

inputs can reproduce some large-scale characteristics but are challenged in simulating small- scale the general structures more precisely as well as simulating the challenging small scale features. In Aug. The Fe Boltzmann temperature lidar was under upgrading and validating at Boulder before its deployment

Chu, Xinzhao

199

Modeling lidar waveforms with time-dependent stochastic radiative transfer theory for remote estimations of forest structure  

E-Print Network (OSTI)

with field data from two conifer forest stands (southern old jack pine and southern old black spruce estimations of forest structure Svetlana Y. Kotchenova,1 Nikolay V. Shabanov,1 Yuri Knyazikhin,1 Anthony B (lidars) have demonstrated a potential for accurate remote sensing of forest biomass and structure

Goldberg, Bennett

200

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

SciTech Connect

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.

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

2014-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
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to obtain the most current and comprehensive results.


201

Shell-isolated nanoparticle-enhanced Raman spectroscopy  

Science Journals Connector (OSTI)

... However, generally substrates based on metals such as Ag, Au and Cu, either with roughened surfaces or in the form of nanoparticles, are required to realise a substantial SERS ... attributed to the Pt–H stretching vibration mode according to the previous reports on highly roughened Pt surfaces. In addition, we collected Raman signals on Pt(111) under the ...

Jian Feng Li; Yi Fan Huang; Yong Ding; Zhi Lin Yang; Song Bo Li; Xiao Shun Zhou; Feng Ru Fan; Wei Zhang; Zhi You Zhou; De Yin Wu; Bin Ren; Zhong Lin Wang; Zhong Qun Tian

2010-03-18T23:59:59.000Z

202

Surface-enhanced Raman scattering from silver electrodes  

SciTech Connect

The chemical and physical origins of the anomalously large enhancement of the Raman scattering cross section for molecules adsorbed on silver electrodes in an electrochemical cell were investigated. The effect of the chemical reactions which occur during the anodization/activation procedure were studied using the Ag-CN system. It was shown that the function of the anodization process is to roughen the electrode surface and create an activated site for bonding to the cyanide. A new nonelectrochemical technique for activating the silver surface, along with a study of the enhanced cyanide Raman scattering in different background electrolytes, showed that the Raman active entity on the surface must be a silver-cyanide complex. In order to study the physical mechanism of the enhancement, the angular dependence of the scattered radiation was measured from pyridine adsorbed on an evaporated silver electrode. Both polycrystalline and single crystalline silver films were used. The angular dependence of the scattered radiation from these films showed that the metal surface was controlling the directional properties of the scattered radiation, and not the polarizability tensor of the adsorbate. Based on these experimental results, it was concluded that for weakly roughened silver electrodes the source of the anomalous enhancement is due to a resonant Raman scattering process.

Trott, G.R.

1982-01-01T23:59:59.000Z

203

Electrochemical and Raman measurements on single-walled carbon nanotubes  

E-Print Network (OSTI)

Electrochemical and Raman measurements on single-walled carbon nanotubes M. Stoll a,*, P performed on a carbon nanotube mat as a working electrode using different salt solutions. The gravimetric capacitance of the nanotube material was estimated and its effective surface area was de- termined in a purely

Nabben, Reinhard

204

Raman Scattering in Carbon Nanotubes Christian Thomsen1  

E-Print Network (OSTI)

energy [4]. Theoretically, the electronic dispersion of nanotubes may be described by an- alyticRaman Scattering in Carbon Nanotubes Christian Thomsen1 and Stephanie Reich2 1 Institut f¨ur Festk of single-walled carbon nanotubes reflect the electron and phonon confinement as well as the cylindrical

Nabben, Reinhard

205

Single-pulse Raman scattering studies of heterogeneous explosive materials  

SciTech Connect

Raman scattering from ambient and shock-loaded heterogeneous (compressed pure polycrystalline) explosive materials has been examined using single-pulse laser excitation. In the case of triamino-trinitrobenzene (TATB), intense nonlinear scattering at 1170 cm/sup -1/ has been observed.

Trott, W.M.; Renlund, A.M.

1985-05-15T23:59:59.000Z

206

Stimulated Raman scattering in an ethanol core microstructured optical fiber  

E-Print Network (OSTI)

Delaye, Anne Rouvie, Jordi Chinaud, Robert Frey, Gérald Roosen Laboratoire Charles Fabry de l'Institut d" Phys. Rev. Lett. 9, 455 (1962) 2. Y.R. Shen "The principles of nonlinear optics" (John Wiley and Sons, New York, 1994). 4. R.Frey, F. Pradère "Powerful tunable infrared generation by stimulated Raman

Paris-Sud XI, Université de

207

Raman Amplification of Laser Pulses in Microcapillary Plasmas  

E-Print Network (OSTI)

of overcoming the power limit of current chirped-pulse-amplification (CPA) CP641, X-Ray Lasers 2002: 8th International Conference on X-Ray Lasers, edited by J. J. Rocca et al. > 2002American Institute of Physics 0 of the optics. Such Raman amplifiers can be useful to produce ultra-intense laser pulses for pumping soft x-ray

208

hal00276997, Raman spectra of misoriented bilayer graphene  

E-Print Network (OSTI)

hal­00276997, version 1 ­ 5 May 2008 Raman spectra of misoriented bilayer graphene P. Poncharal 1 spectra from single layer graphene with a bilayer in which the two layers are arbitrarily misoriented to the similarity of the electronic structures of single layer graphene and misoriented bilayer graphene. Another

Paris-Sud XI, Université de

209

Raman spectroscopy on simple molecular systems at very high density  

SciTech Connect

We present an overview of how Raman spectroscopy is done on simple molecular substances at high pressures. Raman spectroscopy is one of the most powerful tools for studying these substances. It is often the quickest means to explore changes in crystal and molecular structures, changes in bond strength, and the formation of new chemical species. Raman measurements have been made at pressures up to 200 GPa (2 Mbar). Even more astonishing is the range of temperatures (4-5200/degree/K) achieved in various static and dynamic (shock-wave) pressure experiments. One point we particularly wish to emphasize is the need for a good theoretical understanding to properly interpret and use experimental results. This is particularly true at ultra-high pressures, where strong crystal field effects can be misinterpreted as incipient insulator-metal transitions. We have tried to point out apparatus, techniques, and results that we feel are particularly noteworthy. We have also included some of the /open quotes/oral tradition/close quotes/ of high pressure Raman spectroscopy -- useful little things that rarely or never appear in print. Because this field is rapidly expanding, we discuss a number of exciting new techniques that have been informally communicated to us, especially those that seem to open new possibilities. 58 refs., 18 figs.

Schiferl, D.; LeSar, R.S.; Moore, D.S.

1988-01-01T23:59:59.000Z

210

Postdoc Position in Microfluidics and Single Cell Raman Spectroscopy  

E-Print Network (OSTI)

Postdoc Position in Microfluidics and Single Cell Raman Spectroscopy Department of Microbial and Environmental Microfluidics Group (http://web.mit.edu/romanstocker) Department of Civil & Environmental (junior or senior) with strong expertise in microfluidics and an interest in applying it to microbial

Horn, Matthias

211

Laser Raman Spectroscopy in studies of corrosion and electrocatalysis  

SciTech Connect

Laser Raman Spectroscopy (LRS) has become an important tool for the in-situ structural study of electrochemical systems and processes in recent years. Following a brief introduction of the experimental techniques involved in applying LRS to electrochemical systems, we survey the literature for examples of studies in the inhibition of electrode reactions by surface films (e.g., corrosion and passivation phenomena) as well as the acceleration of reactions by electro-sorbates (electrocatalysis). We deal mostly with both normal and resonance Raman effects on fairly thick surface films in contrast to surface-enhanced Raman investigations of monolayer adsorbates, which is covered in another lecture. Laser Raman spectroelectrochemical studies of corrosion and film formation on such metals as Pb, Ag, Fe, Ni, Co, Cr, Au, stainless steel, etc. in various solution conditions are discussed. Further extension of the technique to studies in high-temperature and high-pressure aqueous environments is demonstrated. Results of studies of the structure of corrosion inhibitors are also presented. As applications of the LRS technique in the area of electrocatalysis, we cite studies of the structure of transition metal macrocyclic compounds, i.e., phthalocyanines and porphyrins, used for catalysis of the oxygen reduction reaction. 104 refs., 20 figs.

Melendres, C.A.

1988-01-01T23:59:59.000Z

212

Single Molecule Tip Enhanced Raman Spectroscopy NSF Grant # 1121262  

E-Print Network (OSTI)

MRSEC Single Molecule Tip Enhanced Raman Spectroscopy NSF Grant # 1121262 Matthew D. Sonntag1, it can "see" one single molecule at a time, this was carried out by studying the vibrational signature fingerprint that allows molecule identification. J. Phys. Chem. C, 2012, 116 (1), pp 478­483 · R6G-d4 · R6G-d0

Shahriar, Selim

213

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

SciTech Connect

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.

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

2013-06-11T23:59:59.000Z

214

Raman spectroscopic studies of chemical speciation in calcium chloride melts  

SciTech Connect

Raman spectroscopy was applied to CaCl2 melts at 900 degrees C under both non-electrolyzed and electrolyzed conditions. The later used titania cathodes supplied by TIMET, Inc. and graphite anodes. Use of pulse-gating to collect the Raman spectra successfully eliminated any interference from black-body radiation and other stray light. The spectrum of molten CaCl2 exhibited no distinct, resolvable bands that could be correlated with a calcium chloride complex similar to MgCl42- in MgCl2 melts. Rather, the low frequency region of the spectrum was dominated by a broad “tail” arising from collective oscillations of both charge and mass in the molten salt “network.” Additions of both CaO and Ca at concentrations of a percent or two resulted in no new features in the spectra. Addition of CO2, both chemically and via electrolysis at concentrations dictated by stability and solubility at 900 degrees C and 1 bar pressure, also produced no new bands that could be correlated with either dissolved CO2 or the carbonate ion. These results indicated that Raman spectroscopy, at least under the conditions evaluated in the research, was not well suited for following the reactions and coordination chemistry of calcium ions, nor species such as dissolved metallic Ca and CO2 that are suspected to impact current efficiency in titanium electrolysis cells using molten CaCl2. Raman spectra of TIMET titania electrodes were successfully obtained as a function of temperature up to 900 degrees C, both in air and in-situ in CaCl2 melts. However, spectra of these electrodes could only be obtained when the material was in the unreduced state. When reduced, either with hydrogen or within an electrolysis cell, the resulting electrodes exhibited no measurable Raman bands under the conditions used in this work.

Windisch, Charles F.; Lavender, Curt A.

2005-02-01T23:59:59.000Z

215

Graphene as a Substrate To Suppress Fluorescence in Resonance Raman Spectroscopy  

E-Print Network (OSTI)

Resonance Raman spectroscopy (RRS), which can enhance Raman signal by 107 times than normal Raman spectroscopy, is a powerful approach to characterize structures of chemicals (especially biomolecules) at low concentrations.1-4 However, fluorescence (FL) background is a major obstacle in RRS because the FL cross section (?10-16 cm2) is much larger than the RRS cross section (?10-22 cm2).3 Several approaches, such as ultraviolet RRS (UV-RRS),1 time-resolved Raman detection,5,6 femtosecond broadband stimu-lated Raman spectroscopy (FSRS),7 and coherent anti-Stokes Raman spectroscopy (CARS),8 have been used to suppress or reject FL background in RRS. However, these approaches need expensive and complex equipments and have other limitations, such as sample degradation in UV-RRS. Surface-enhanced Raman spectroscopy (SERS) is another powerful approach to characterize structures of chemicals at extremely low concentrations or even at the single

Liming Xie; Xi Ling; Yuan Fang; Jin Zhang; Zhongfan Liu

2009-01-01T23:59:59.000Z

216

A Method for Estimating the Turbulent Kinetic Energy Dissipation Rate from a Vertically Pointing Doppler Lidar, and Independent Evaluation from Balloon-Borne In Situ Measurements  

Science Journals Connector (OSTI)

A method of estimating dissipation rates from a vertically pointing Doppler lidar with high temporal and spatial resolution has been evaluated by comparison with independent measurements derived from a balloon-borne sonic anemometer. This method ...

Ewan J. O’Connor; Anthony J. Illingworth; Ian M. Brooks; Christopher D. Westbrook; Robin J. Hogan; Fay Davies; Barbara J. Brooks

2010-10-01T23:59:59.000Z

217

Raman scheme for adjustable-bandwidth quantum memory  

SciTech Connect

We propose a scenario of quantum memory for light based on Raman scattering. The storage medium is a vapor and the different spectral components of the input pulse are stored in different atomic velocity classes. One uses appropriate pulses to reverse the resulting Doppler phase shift and to regenerate the input pulse, without distortion, in the backward direction. The different stages of the protocol are detailed and the recovery efficiency is calculated in the semiclassical picture. Since the memory bandwidth is determined by the Raman transition Doppler width, it can be adjusted by changing the angle between the input pulse wave vector and the control beams. The optical depth also depends on the beam angle. As a consequence the available optical depth can be optimized depending on the needed bandwidth. The predicted recovery efficiency is close to 100% for large optical depth.

Le Goueet, J.-L.; Berman, P. R. [Laboratoire Aime Cotton, CNRS UPR3321, Universite Paris Sud, Batiment 505, Campus Universitaire, 91405 Orsay (France); Department of Physics and Michigan Center for Theoretical Physics, University of Michigan, Ann Arbor, Michigan 48109-1040 (United States)

2009-07-15T23:59:59.000Z

218

Theory of Raman scattering in coupled electron-phonon systems  

Science Journals Connector (OSTI)

The Raman spectrum is calculated for a coupled conduction-electron–phonon system in the zero-momentum-transfer limit. The Raman scattering is due to electron-hole excitations and phonons as well. The phonons of those branches that contribute to the electron self-energy and the correction of the electron-phonon vertex are assumed to have flat energy dispersion (the Einstein phonons). The effect of electron-impurity scattering is also incorporated. Both the electron-phonon interaction and the electron-impurity interaction cause the fluctuation of the electron distribution between different parts of the Fermi surface, which results in overdamped zero-sound modes of various symmetries. The scattering cross section is obtained by solving the Bethe-Salpeter equation. The spectrum shows a lower threshold at the smallest Einstein phonon energy when only the electron-phonon interaction is taken into consideration. When impurities are also taken into consideration, the threshold disappears.

K. Itai

1992-01-01T23:59:59.000Z

219

Raman Spectra of Graphite Oxide and Functionalized Graphene Sheets  

Science Journals Connector (OSTI)

Konstantin N. Kudin ,† Bulent Ozbas ,‡ Hannes C. Schniepp ,‡ Robert K. Prud'homme ,‡ Ilhan A. Aksay ,‡ and Roberto Car *† ... 25 Theoretical evaluation of the Raman spectra requires first-, second-, and third-order energy derivatives, among which the most demanding are the second-order derivatives of the energy with respect to the atomic positions (force constants)26 and the third-order polarizability derivatives, twice with respect to the electric field (yielding polarizability) and once with respect to the atomic positions (Raman intensity tensors). ... and the described stable structural isomers (obtained by 2-atom transformations), the ?-orbital energy levels, ?-electron populations, bond orders, and delocalization (resonance) energies were obtained in Hueckel and approx.-SCF ...

Konstantin N. Kudin; Bulent Ozbas; Hannes C. Schniepp; Robert K. Prud'homme; Ilhan A. Aksay; Roberto Car

2007-12-22T23:59:59.000Z

220

X-ray Raman scattering study of aligned polyfluorene  

E-Print Network (OSTI)

We present a non-resonant inelastic x-ray scattering study at the carbon K-edge on aligned poly[9,9-bis(2-ethylhexyl)-fluorene-2,7-diyl] and show that the x-ray Raman scattering technique can be used as a practical alternative to x-ray absorption measurements. We demonstrate that this novel method can be applied to studies on aligned $\\pi$-conjugated polymers complementing diffraction and optical studies. Combining the experimental data and a very recently proposed theoretical scheme we demonstrate a unique property of x-ray Raman scattering by performing the symmetry decomposition on the density of unoccupied electronic states into $s$- and $p$-type symmetry contributions.

S. Galambosi; M. Knaapila; J. A. Soininen; K. Nyg\\aard; S. Huotari; F. Galbrecht; U. Scherf; A. P. Monkman; K. Hämäläinen

2006-08-29T23:59:59.000Z

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Raman/FTIR spectroscopy of oil shale retort gases  

SciTech Connect

A Raman facility was assembled in order to aid in the evaluation of the feasibility of using Raman or FTIR spectroscopy for analyzing gas mixtures of interest in oil shale. Applications considered in oil shale research included both retort monitoring and laboratory kinetic studies. Both techniques gave limits of detection between 10 and 1000 ppM for ten representative pertinent gases. Both techniques are inferior as a general analytical technique for oil shale gas analysis in comparison with mass spectroscopy, which had detection limits between 1 and 50 ppM for the same gases. The conclusion of the feasibility study was to recommend that mass spectroscopic techniques be used for analyzing gases of interest to oil shale.

Richardson, J H; Monaco, S B; Sanborn, R H; Hirschfeld, T B; Taylor, J R

1982-08-01T23:59:59.000Z

222

Multi mode nano scale Raman echo quantum memory  

E-Print Network (OSTI)

Low loss magnetic surface plasmon polariton (SPP) modes characterized by enhanced electrical field component and subwavelength confinement on the dielectric and negative-index metamaterial interface are presented. We demonstrate a possibility of storage and perfect retrieval of the low loss magnetic SPP fields by using a photon echo quantum memory on Raman atomic transition. We describe specific properties of the proposed technique which opens a possibility for efficient nano scale multi-mode quantum memory.

S. A. Moiseev; E. S. Moiseev

2010-01-31T23:59:59.000Z

223

Charge transfer effects in surface?enhanced Raman scatteringa)  

Science Journals Connector (OSTI)

Surface?enhanced Raman scattering(SERS) due to charge?transferinteractions between the adsorbed molecule and the metal surface is analyzed using the semiempirical Wolfsberg–Helmholz method to relate the molecule–surface interactions and the resulting charge?transfer states to the overlap integrals between the metal conduction?band orbitals and an acceptor or donor molecular orbital of the molecule. Calculations for the model system of ethylene adsorbed on silver with charge?transfer excitation of an electron from the metal to the antibonding etylene ? orbital show that charge?transfer Raman enhancements of the order of 10 to 1000 are possible if the charge?transfer band is partially resonant with the exciting radiation. Symmetric vibrations usually will be enhanced substantially more than nonsymmetric ones by this mechanism because the vibrational coupling is primarily Franck–Condon rather than Herzberg–Teller. The presence of overtone and combination bands in charge?transfer?enhanced Raman spectra is also possible.

Frank J. Adrian

1982-01-01T23:59:59.000Z

224

Characterization of polysilicon films by Raman spectroscopy and transmission electron microscopy: A comparative study  

SciTech Connect

Samples of chemically-vapor-deposited micrometer and sub-micrometer-thick films of polysilicon were analyzed by transmission electron microscopy (TEM) in cross-section and by Raman spectroscopy with illumination at their surface. TEM and Raman spectroscopy both find varying amounts of polycrystalline and amorphous silicon in the wafers. Raman spectra obtained using blue, green and red excitation wavelengths to vary the Raman sampling depth are compared with TEM cross-sections of these films. Films showing crystalline columnar structures in their TEM micrographs have Raman spectra with a band near 497 cm{sup {minus}1} in addition to the dominant polycrystalline silicon band (521 cm{sup {minus}1}). The TEM micrographs of these films have numerous faulted regions and fringes indicative of nanometer-scale silicon structures, which are believed to correspond to the 497cm{sup {minus}1} Raman band.

Tallant, D.R.; Headley, T.J.; Medernach, J.W. [Sandia National Labs., Albuquerque, NM (United States); Geyling, F. [SEMATECH, Austin, TX (United States)

1993-11-12T23:59:59.000Z

225

Development of a time-gated system for Raman spectroscopy of biological samples  

Science Journals Connector (OSTI)

A time gating system has been constructed that is capable of recording high quality Raman spectra of highly fluorescing biological samples while operating below the photodamage...

Knorr, Florian; Smith, Zachary J; Wachsmann-Hogiu, Sebastian

2010-01-01T23:59:59.000Z

226

Characterization of Woody and Herbaceous Biomasses Lignin Composition with 1064 nm Dispersive Multichannel Raman Spectroscopy  

Science Journals Connector (OSTI)

Biomass representing different classes of bioenergy feedstocks, including woody and herbaceous species, was measured with 1064 nm Raman spectroscopy. Pine, oak, poplar, kenaf,...

Lupoi, Jason S; Smith, Emily A

2012-01-01T23:59:59.000Z

227

Looking Inside Catalyst Extrudates with Time-Resolved Surface-Enhanced Raman Spectroscopy (TR-SERS)  

Science Journals Connector (OSTI)

Raman spectroscopy is one of the major characterization methods employed over the last few decades as a nondestructive technique for the study of heterogeneous catalysts and related...

Harvey, Clare E; Petterson, Ingeborg E Iping; Weckhuysen, Bert M; Gooijer, Cees; Ariese, Freek; Mank, Arjan J G

2012-01-01T23:59:59.000Z

228

Raman Microscopy and Mapping as a Probe for Photodegradation in Surface Relief Gratings Recorded on Layer-by-Layer Films of Congo Red/Polyelectrolyte  

Science Journals Connector (OSTI)

Raman microscopy, mapping, and surface-enhanced Raman scattering techniques have been applied to investigate the degradation of Congo Red (CR) in a surface relief grating (SRG)...

Constantino, C J L; Aroca, R F; He, J -A; Zucolotto, V; Li, L; Oliveira, O N; Kumar, J; Tripathy, S K

2002-01-01T23:59:59.000Z

229

Raman microscopy and x-ray fluorescence analysis of pigments on medieval and Renaissance Italian manuscript cuttings  

Science Journals Connector (OSTI)

...are the predominant elements with small amounts of arsenic and mercury (Fig. 4, top). Medieval...syntheses . J Raman Spectrosc 30 : 355 – 360 . 38 de Faria DLA Venauncio Silva S de Oliveira MT ( 1997 ) Raman microspectroscopy...

Lucia Burgio; Robin J. H. Clark; Richard R. Hark

2010-01-01T23:59:59.000Z

230

Raman scattering and X-ray diffraction study of the thermal decomposition of an ettringite-group crystal  

Science Journals Connector (OSTI)

...?A Raman scattering and X-ray diffraction study of the thermal decomposition of a naturally occurring, ettringite-group crystal is presented. Raman spectra, ... previous studies that reported higher temperatur...

S. K. Deb; M. H. Manghnani; K. Ross; R. A. Livingston…

2003-02-01T23:59:59.000Z

231

Raman spectroscopy of selected arsenates—implications for soil remediation  

Science Journals Connector (OSTI)

The contamination of soils with heavy metals such as As, Cr and Cu is of great importance; the remediation of such soils even more so. Arsenic compounds are prevalent in soils either through leaching of mine tailings, the use of Cu/Cr/As as a wood preservative or through the use of arsenic in cattle dips. The arsenic compounds in soils and leachates can be highly reactive and mobile, resulting in the formation of metal arsenate compounds. Of these compounds, one such set of minerals that can be formed is the vivianite arsenate minerals. Raman spectroscopy has been used to characterise the vivianite arsenates and to identify arsenic contaminants in a soil.

Ray L. Frost; Theo Kloprogge; Matthew L. Weier; Wayde N. Martens; Z. Ding; Howell G.H. Edwards

2003-01-01T23:59:59.000Z

232

Geometrical constraints on plasma couplers for Raman compression  

SciTech Connect

Backward Raman compression in plasma is based on a 3-wave resonant interaction, which includes two counter-propagating laser pulses (pump and seed pulses) and an electron plasma wave (Langmuir wave). The resonant interaction can be ensured in nearly homogeneous plasmas. However, for high-power, large-aperture experiments, the homogeneous region becomes pancake-shaped and would likely be surrounded by thicker regions of inhomogeneous plasma. When these inhomogeneous plasma regions are extensive, significant inverse bremsstrahlung and seed dispersion may impede the compression effect. These deleterious effects may, however, be mitigated by chirping the seed and pump pulses.

Toroker, Z. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Malkin, V. M. [Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08544 (United States); Balakin, A. A.; Fraiman, G. M. [Institute of Applied Physics RAS, Nizhnii Novgorod 603950 (Russian Federation); Fisch, N. J. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08544 (United States)

2012-08-15T23:59:59.000Z

233

Laser-Scanning Coherent Anti-Stokes Raman Scattering Microscopy and Applications to Cell Biology  

E-Print Network (OSTI)

Laser-Scanning Coherent Anti-Stokes Raman Scattering Microscopy and Applications to Cell Biology Ji 11747-3157 USA ABSTRACT Laser-scanning coherent anti-Stokes Raman scattering (CARS) microscopy with fast., 1990). Duncan et al. constructed the first CARS microscope by use of two dye laser beams

Xie, Xiaoliang Sunney

234

Micro-Raman Spectroscopy of Algae: Composition Analysis and Fluorescence Background Behavior  

E-Print Network (OSTI)

analysis; biodiesel Introduction To date, analysis of algae composition is a multi-staged processARTICLE Micro-Raman Spectroscopy of Algae: Composition Analysis and Fluorescence Background performed using Stokes Raman scattering for compositional analysis of algae. Two algal species, Chlorella

235

Chapter 14 Treatise on Geochemistry Raman and Nuclear Resonant Spectroscopy in Geosciences  

E-Print Network (OSTI)

Chapter 14 Treatise on Geochemistry 1 Raman and Nuclear Resonant Spectroscopy in Geosciences Jung Advanced Photon Source, Argonne National Laboratory, Argonne, IL, USA Alexander F. Goncharov Geophysical technical advances in Raman and nuclear resonance spectroscopy (both Mössbauer spectroscopy and nuclear

Lin, Jung-Fu "Afu"

236

Raman studies of corrosion layers formed on archaeological irons in various media  

E-Print Network (OSTI)

147 Raman studies of corrosion layers formed on archaeological irons in various media Ludovic mandana.saheb@cea.fr, f philippe.dillmann@cea.fr Keywords: Raman spectroscopy, iron corrosion, ancient artefact, imaging. Abstract. The description and identification of corrosion products formed

237

Raman excitation profiles for the (n1, n2) assignment in carbon nanotubes  

E-Print Network (OSTI)

Raman excitation profiles for the (n1, n2) assignment in carbon nanotubes H. Telg , J. Maultzsch indices n1 and n2 in semiconducting and metallic nanotubes was performed comparing resonance Raman nanotube families. Ever since the discovery of how to keep isolated nanotubes from rebundeling in solu

Nabben, Reinhard

238

10.1098/rsta.2004.1444 Resonant Raman spectroscopy of nanotubes  

E-Print Network (OSTI)

10.1098/rsta.2004.1444 Resonant Raman spectroscopy of nanotubes By Christian Thomsen1 , Stephanie. The experimental situation in carbon nanotubes is reviewed in view of these criteria. The evidence for the D mode for the application of Raman scattering to the characterization of nanotubes are discussed. Keywords: carbon nanotubes

Nabben, Reinhard

239

POLARIZED RAMAN MEASUREMENTS IN ZEOLITE-GROWN SINGLE-WALL CARBON NANOTUBES  

E-Print Network (OSTI)

POLARIZED RAMAN MEASUREMENTS IN ZEOLITE-GROWN SINGLE-WALL CARBON NANOTUBES J. Maultzsch*, P. M, Hardenbergstr. 36, D-10623 Berlin, E-Mail: janina@physik.tu-berlin.de The Raman spectra of carbon nanotubes able to grow carbon nanotubes inside the channels of an AlPO4 zeolite crystal [1]. The directions

Nabben, Reinhard

240

Raman characterization of boron-doped multiwalled carbon nanotubes J. Maultzsch,a)  

E-Print Network (OSTI)

. We interpret this result as an indication that the high-energy mode in carbon nanotubes is defectRaman characterization of boron-doped multiwalled carbon nanotubes J. Maultzsch,a) S. Reich, and C of boron-doped multiwalled carbon nanotubes. The Raman intensities are analyzed as a function

Nabben, Reinhard

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Raman scattering in carbon nanotubes Technische Universitat Berlin, Hardenbergstrasse 36, 10623 Berlin, Germany  

E-Print Network (OSTI)

in carbon nanotubes is the strong excitation-energy dependent Raman shift of the socalled D-mode, which for instance for metallic nanotubes near the K-point. For a given incident photon energy, there is an incomingRaman scattering in carbon nanotubes C. Thomsen Technische Universit¨at Berlin, Hardenbergstrasse

Nabben, Reinhard

242

Origin of the high-energy Raman modes in single-wall carbon nanotubes  

E-Print Network (OSTI)

Origin of the high-energy Raman modes in single-wall carbon nanotubes J. Maultzsch, C. Thomsen, S nanotubes. Similar to the disorder-induced D mode, the high-energy modes are deter- mined by double of the first-order high-energy Raman modes in carbon nanotubes has been a puzzling question since the first

Nabben, Reinhard

243

Raman spectroscopy on single and multi-walled nanotubes under high pressure  

E-Print Network (OSTI)

dependence of the high-energy Raman modes in single and multi-walled carbon nanotubes was measuredRaman spectroscopy on single and multi-walled nanotubes under high pressure C. Thomsen, S. Reich, H properties of carbon nanotubes have become of scienti c interest since it was recognized that the low atomic

Nabben, Reinhard

244

In situ Raman spectroscopy of lanthanum-strontium-cobaltite thin films  

E-Print Network (OSTI)

Raman spectroscopy is used to probe the structural change of Lanthanum Strontium Cobaltite (La1.xSrxCoO 3 -8) thin films across change in composition (0%-60% strontium) and temperature (30*C-520°C). Raman shift peaks were ...

Breucop, Justin Daniel

2012-01-01T23:59:59.000Z

245

Raman intensity measurements of single-walled carbon nanotube suspensions as a quantitative technique  

E-Print Network (OSTI)

Raman intensity measurements of single-walled carbon nanotube suspensions as a quantitative, Biological and Materials Engineering, Carbon Nanotube Technology Center (CANTEC), University of Oklahoma, 100 the purity of single-walled carbon nanotube (SWCNT) bulk samples based on Raman spectroscopy is reported

Resasco, Daniel

246

RAMAN SPECTROSCOPY OF MACROSCALE FIBERS COMPRISED OF CARBON NANOTUBES OF DIFFERENT  

E-Print Network (OSTI)

RAMAN SPECTROSCOPY OF MACROSCALE FIBERS COMPRISED OF CARBON NANOTUBES OF DIFFERENT LENGTHS UNDER University Carbon nanotube (CNT) fibers are considered an excellent material for high performance engineering) Fibers Raman Spectroscopy of Macroscopic Fibers Spun from Carbon Nanotubes under Tensile Strain D

Mellor-Crummey, John

247

Sulfates on Mars: A systematic Raman spectroscopic study of hydration states of magnesium sulfates  

E-Print Network (OSTI)

Sulfates on Mars: A systematic Raman spectroscopic study of hydration states of magnesium sulfates of magnesium sulfates on the martian surface. In situ identification of the hydration states of magnesium of magnesium sulfate. Characteristic and distinct Raman spectral patterns were observed for each of the 11

248

UV Resonance Raman Characterization of Polycyclic Aromatic Hydrocarbons in Coal Liquid Distillates*  

E-Print Network (OSTI)

UV Resonance Raman Characterization of Polycyclic Aromatic Hydrocarbons in Coal Liquid Distillates samples, such as petroleum and coal, or for man-made samples, such as coal liquids, a major desire- nique for studying coal-liquid samples. 1-4 We demon- strated that the Raman spectra of polycyclic

Asher, Sanford A.

249

Micro-Raman spectroscopy of refractive index microstructures in silicone-based hydrogel  

E-Print Network (OSTI)

Micro-Raman spectroscopy of refractive index microstructures in silicone-based hydrogel polymers 26, 2009 (Doc. ID 102944); published March 3, 2009 Micro-Raman spectroscopy was used to study transparent hydro- gel polymer materials through a high (or medium) nu- merical aperture (NA) objective

Novotny, Lukas

250

Demonstration of stimulated Raman scattering in the evanescent field of a tapered nanofiber  

E-Print Network (OSTI)

in the following figure the modal Raman gain for a nanofiber immersed in a mixture of toluene and ethanol ; ethanol is used to reduce the refractive index below the one of silica. Fig. 1: Raman gain experienced by the guided mode versus the nanofiber radius and the fraction volume of toluene in a mixture of toluene-ethanol

Boyer, Edmond

251

Forward Raman compression via photonic band gap in metals or warm dense matter  

SciTech Connect

The group velocity of a light pulse in photonic band gap material could considerably deviate from the speed of light in vacuum. A forward stoke and a pump pulse of different speeds would enable the Raman compression in metals or the warm dense matter. A small window of the parameter regime, where the compression is feasible via the forward Raman scattering, is identified.

Son, S. [18 Caleb Lane, Princeton, New Jersey 08540 (United States); Moon, Sung Joon [Program in Applied and Computational Mathematics, Princeton University, Princeton, New Jersey 08544 (United States)

2011-08-15T23:59:59.000Z

252

Detection and quantitative analysis of ferrocyanide and ferricyanide: FY 93 Florida State University Raman spectroscopy report  

SciTech Connect

This report provides a summary of work to develop and investigate the feasibility of using Raman spectroscopy with tank waste materials. It contains Raman spectra from organics, such as ethylenediaminetetraacetic acid (EDTA), hydroxyethylenediaminetetraacteic acid (HEDTA), imino diacetic acid (IDA), kerosene, tributyl phosphate (TBP), acetone and butanol, anticipated to be present in tank wastes and spectra from T-107 real and BY-104 simulant materials. The results of investigating Raman for determining moisture content in tank materials are also presented. A description of software algorithms developed to process Raman spectra from a dispersive grating spectrometer system and an in initial design for a data base to support qualitative and quantitative application of remote Raman sensing with tank wastes.

Mann, C.K.; Vickers, T.J. [Florida State Univ., Tallahassee, FL (United States). Dept. of Chemistry

1994-10-11T23:59:59.000Z

253

New C-H Stretching Vibrational Spectral Features in the Raman Spectra of Gaseous and Liquid Ethanol  

E-Print Network (OSTI)

New C-H Stretching Vibrational Spectral Features in the Raman Spectra of Gaseous and Liquid Ethanol Traditionally, the Raman spectrum of ethanol in the C-H vibrational stretching region between 2800 cm-1 and 3100, and the -CH3 antisymmetric stretching. In this report, new Raman spectral features were observed for ethanol

Liu, Shilin

254

The effect of substrates on the Raman spectrum of graphene: Graphene-on-sapphire and graphene-on-glass  

E-Print Network (OSTI)

The effect of substrates on the Raman spectrum of graphene: Graphene- on-sapphire and graphene The authors investigated the influence of substrates on Raman scattering spectrum from graphene. The room-temperature Raman signatures from graphene layers on GaAs, sapphire, and glass substrates were compared with those

255

Pump side scattering in ultrapowerful backward Raman amplifiers A. A. Solodov, V. M. Malkin, and N. J. Fisch  

E-Print Network (OSTI)

Pump side scattering in ultrapowerful backward Raman amplifiers A. A. Solodov, V. M. Malkin, and N of a laser pump by plasma noise might be suppressed by an appropriate detuning of the Raman resonance, even scattering of laser pumps by plasma noise in backward Raman amplifiers. Though its growth rate is smaller

256

Raman scattering induced by carbon vacancies in TiCx  

Science Journals Connector (OSTI)

Carbon vacancies in cubic TiCx induce a first-order Raman spectrum, the three independent components of which have been studied for x=0.97, 0.90, and 0.80. The spectra mimic, approximately, the calculated phonon density of states with some lowering of the upper edge of the gap between the acoustical- and optical-phonon regions and with some filling in of the valleys between prominent peaks for lower values of x. There is a tendency towards saturation of the integrated spectra with increasing vacancy concentration. Expressions are derived for the efficiency of light scattering from a disordered metal crystal. They agree with the corresponding results for transparent crystals when corrected for geometric and propagation effects. Analysis of the data using a Raman sum rule indicates that the mean-square polarizability derivative induced by carbon vacancies on carbon and titanium atoms is about the same; the large magnitudes observed here are evidence for resonant enhancement. The probabilities for clustering of vacancies are discussed, and it is concluded that clustering is so likely, even for x=0.97, that the experimental results cannot be interpreted as characteristic of isolated vacancies.

M. V. Klein, John A. Holy, and W. S. Williams

1978-02-15T23:59:59.000Z

257

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

DOE Data Explorer (OSTI)

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

Gangodagamage, Chandana; Wullschleger, Stan

258

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

SciTech Connect

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

Gangodagamage, Chandana; Wullschleger, Stan

2014-07-03T23:59:59.000Z

259

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

DOE Patents (OSTI)

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.

Alfano, Robert R. (Bronx, NY); Wang, Wubao (Flushing, NY)

2003-05-06T23:59:59.000Z

260

Operating Regime for a Backward Raman Laser Amplifier in Preformed Plasma  

SciTech Connect

A critical issue in the generation of ultra-intense, ultra-short laser pulses by backward Raman scattering in plasma is the stability of the pumping pulse to premature backscatter from thermal fluctuations in the preformed plasma. Malkin et al. [V.M. Malkin, et al., Phys. Rev. Lett. 84 (6):1208-1211, 2000] demonstrated that density gradients may be used to detune the Raman resonance in such a way that backscatter of the pump from thermal noise can be stabilized while useful Raman amplification persists. Here plasma conditions for which the pump is stable to thermal Raman backscatter in a homogeneous plasma and the density gradients necessary to stabilize the pump for other plasma conditions are quantified. Other ancillary constraints on a Raman amplifier are also considered to determine a specific region in the Te-he plane where Raman amplification is feasible. By determining an operability region, the degree of uncertainty in density or temperature tolerable for an experimental Raman amplifier is thus also identified. The fluid code F3D, which includes the effects of thermal fluctuations, is used to verify these analytic estimates.

Daniel S. Clark; Nathaniel J. Fisch

2003-02-06T23:59:59.000Z

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

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

DOE Patents (OSTI)

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.

Alfano, Robert R. (Bronx, NY); Wang, Wubao (Flushing, NY)

2000-11-21T23:59:59.000Z

262

Real-Time Raman Gas Composition Sensor.pdf  

NLE Websites -- All DOE Office Websites (Extended Search)

Sensor Sensor Opportunity Technology/Capability Overview Benefits to Partner Development Status Contact The NETL Real-time Raman Gas Composition Analyzer determines the composition of a flowing gaseous sample in real-time and provides the concentration of each gas in that sample. . . . ‡ Testing partners would have the opportunity to evaluate the performance of the prototype system, implement new feed-forward controls, and may help shape the commercial product configuration ‡ This sensor will greatly benefit the power industry, as well as other industries utilizing gaseous input or output streams by enabling smarter control to increase process efficiency and reduce emissions ‡ We are seeking opportunities to field test the prototype instruments in power and industrial applications, as well

263

Q-branch Raman scattering and modern kinetic thoery  

SciTech Connect

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.

Monchick, L. [The Johns Hopkins Univ., Laurel, MD (United States)

1993-12-01T23:59:59.000Z

264

Detection of volatile organic compounds using surface enhanced Raman scattering  

SciTech Connect

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.

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

2012-03-22T23:59:59.000Z

265

Time?resolved anisotropic coherent anti?Stokes Raman scattering: A new probe of reorientational dynamics  

E-Print Network (OSTI)

anti-Stokes Raman scattering (TRA CARS) and spontaneous Raman (TRA Raman) as probes of rota­ tional motion. II. THEORY When a sample system is illuminated by three laser beams at frequencies (Uo, (UI, and (U2, the incident fields induce a third... is described by a nonlinear sus­ ceptibility tensor containing three independent compo­ nents in the L=O subspace and six independent compo­ nents in the L = 2 subspace. First we write the molecular susceptibility MU11(0) iIi terms of the direct product...

Wan, Chaozhi; Johnson, Carey K.

1993-09-01T23:59:59.000Z

266

Surface enhanced Raman scattering of aged graphene: Effects of annealing in vacuum  

SciTech Connect

In this paper, we report a simple method to recover the surface enhanced Raman scattering activity of aged graphene. The Raman signals of Rhodamine molecules absorbed on aged graphene are dramatically increased after vacuum annealing and comparable to those on fresh graphene. Atomic force microscopy measurements indicate that residues on aged graphene surface can efficiently be removed by vacuum annealing, which makes target molecule closely contact with graphene. We also find that the hole doping in graphene will facilitate charge transfer between graphene and molecule. These results confirm the strong Raman enhancement of target molecule absorbed on graphene is due to the charge transfer mechanism.

Wang Yingying; Li Aizhi; Qu Shiliang [Department of Optoelectronic Science, Harbin Institute of Technology at Weihai, Weihai 264209 (China); Ni Zhenhua; Zafar, Zainab; Qiu Teng [Department of Physics, Southeast University, Nanjing 211189 (China); Zhang Yan; Ni Zhonghua [Jiangsu Key Laboratory for Design and Fabrication of Micro-Nano Biomedical Instruments, School of Mechanical Engineering, Southeast University, Nanjing 211189 (China); Yu Ting; Shen Zexiang [Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371 (Singapore)

2011-12-05T23:59:59.000Z

267

Continuous-wave solid-state two-Stokes Raman laser  

SciTech Connect

We report an experimental study of the first cw solid-state Raman laser operating simultaneously at the frequencies of the first and second Stokes components. Simultaneous generation is ensured by a cavity with an enhanced finesse at both Stokes frequencies. The threshold pump powers for the first (3.4 W) and second (3.67 W) Stokes components suggest that the second Stokes generation follows a cascade mechanism. We demonstrate for the first time Raman conversion with intensity stability exceeding the pump radiation stability and show that this approach may find application in Raman spectroscopy. (special issue devoted to the 80th birthday of S.A. Akhmanov)

Grabchikov, A S; Lisinetskii, V A; Orlovich, V A [B.I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, Minsk (Belarus); Schmitt, M; Schluecker, S; Kuestner, B; Kiefer, W [Institut fuer Physikalische Chemie, Universitat Wuerzburg, Wuerzburg (Germany)

2009-07-31T23:59:59.000Z

268

Third harmonic stimulated Raman backscattering of laser in a magnetized plasma  

SciTech Connect

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.

Paknezhad, Alireza [Physics Department, Shabestar Branch, Islamic Azad University, Shabestar (Iran, Islamic Republic of)] [Physics Department, Shabestar Branch, Islamic Azad University, Shabestar (Iran, Islamic Republic of); Dorranian, Davoud [Laser Lab., Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of)] [Laser Lab., Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, Tehran (Iran, Islamic Republic of)

2013-09-15T23:59:59.000Z

269

Q. J. R. Meteorol. Soc. (2003), 129, pp. 30793098 doi: 10.1256/qj. Simulation of Wind Profiles from a Space-borne Doppler Wind Lidar  

E-Print Network (OSTI)

Q. J. R. Meteorol. Soc. (2003), 129, pp. 3079­3098 doi: 10.1256/qj. Simulation of Wind Profiles on numerical weather prediction and climate processes. This paper describes the simulation of Aeolus LOS wind from a Space-borne Doppler Wind Lidar By G.J. MARSEILLE and A. STOFFELEN KNMI, The Netherlands

Stoffelen, Ad

270

Generated using version 3.0 of the official AMS LATEX template A remotely-operated lidar for aerosol, temperature, and water  

E-Print Network (OSTI)

Generated using version 3.0 of the official AMS LATEX template A remotely-operated lidar for aerosol, temperature, and water vapor profiling in the High Arctic. G. J. Nott, T. J. Duck, J. G. Doyle, M. E. W. Coffin, C. Perro, C. P. Thackray, and J. R. Drummond Department of Physics and Atmospheric

Duck, Thomas J.

271

Proceedings of EARSeL-SIG-Workshop LIDAR, Dresden/FRG, June 16 17, 2000 EARSeL eProceedings No. 1 77  

E-Print Network (OSTI)

77 MARINE CODE FOR MODELLING RANGE RESOLVED OCEANOGRAPHIC LIDAR FLUOROSENSOR MEASUREMENTS R. Barbini1 environment. The laser radiation interaction processes of diffusion, re-emission, refraction and absorption in the frame of the Italian Research Pro- gram for Antarctica (PNRA), has been designed to remotely detect

Oldenburg, Carl von Ossietzky Universität

272

Cloud fraction, liquid and ice water contents derived from long-term radar, lidar, and microwave radiometer data are systematically compared to models to quantify and  

E-Print Network (OSTI)

Cloud fraction, liquid and ice water contents derived from long-term radar, lidar, and microwave a systematic evaluation of clouds in forecast models. Clouds and their associated microphysical processes for end users of weather forecasts, who may be interested not only in cloud cover, but in other variables

Hogan, Robin

273

Evaluation of Cloud-Phase Retrieval Methods for SEVIRI on Meteosat-8 Using Ground-Based Lidar and Cloud Radar Data  

E-Print Network (OSTI)

Evaluation of Cloud-Phase Retrieval Methods for SEVIRI on Meteosat-8 Using Ground-Based Lidar and Cloud Radar Data ERWIN L. A. WOLTERS, ROBERT A. ROEBELING, AND ARNOUT J. FEIJT Royal Netherlands 2007) ABSTRACT Three cloud-phase determination algorithms from passive satellite imagers are explored

Stoffelen, Ad

274

A Critical Review of the Database Acquired for the Long-Term Surveillance of the Middle Atmosphere by the French Rayleigh Lidars  

Science Journals Connector (OSTI)

The database obtained by Rayleigh lidars over the south of France is now used for monitoring the middle-atmosphere structure and to validate satellite data. For these reasons it is crucial to ensure the quality of the data. The purpose of this ...

P. Keckhut; A. Hauchecorne; M. L. Chanin

1993-12-01T23:59:59.000Z

275

A comparison of automated land cover/use classification methods for a Texas bottomland hardwood system using lidar, spot-5, and ancillary data  

E-Print Network (OSTI)

decisions affecting these disappearing systems. SPOT-5 imagery from 2005 was combined with Light Detection and Ranging (LiDAR) data from 2006 and several ancillary datasets to map a portion of the bottomland hardwood system found in the Sulphur River Basin...

Vernon, Zachary Isaac

2009-05-15T23:59:59.000Z

276

Research Highlight  

NLE Websites -- All DOE Office Websites (Extended Search)

Raman Lidar Observations of Aerosol Humidification Near Clouds Raman Lidar Observations of Aerosol Humidification Near Clouds Submitter: Ferrare, R. A., NASA - Langley Research Center Area of Research: Aerosol Properties Working Group(s): Aerosol Journal Reference: Ferrare, R., et al., Evaluation of Daytime Measurements of Aerosols and Water Vapor Made by an Operational Raman Lidar over the Southern Great Plains, J. Geophys. Res., 111, D05S08, doi:10.1029/2005JD005836, 2006. Relative humidity profiles derived from the Raman lidar during the ALIVE 2005 field experiment. Aerosol extinction profiles derived from the Raman lidar during the ALIVE 2005 field experiment. Aerosol humidification factor f(RH) from Raman lidar measured profiles of aerosol extinction and relative humidity. Upgrades to the Raman lidar at the ARM Climate Research Facility (ACRF)

277

Features of point clouds synthesized from multi-view ALOS/PRISM data and comparisons with LiDAR data in forested areas  

Science Journals Connector (OSTI)

Abstract LiDAR waveform data from airborne LiDAR scanners (ALS) e.g. the Land Vegetation and Ice Sensor (LVIS) have been successfully used for estimation of forest height and biomass at local scales and have become the preferred remote sensing dataset. However, regional and global applications are limited by the cost of the airborne LiDAR data acquisition and there are no available spaceborne LiDAR systems. Some researchers have demonstrated the potential for mapping forest height using aerial or spaceborne stereo imagery with very high spatial resolutions. For stereo images with global coverage but coarse resolution new analysis methods need to be used. Unlike most research based on digital surface models, this study concentrated on analyzing the features of point cloud data generated from stereo imagery. The synthesizing of point cloud data from multi-view stereo imagery increased the point density of the data. The point cloud data over forested areas were analyzed and compared to small footprint LiDAR data and large-footprint LiDAR waveform data. The results showed that the synthesized point cloud data from ALOS/PRISM triplets produce vertical distributions similar to LiDAR data and detected the vertical structure of sparse and non-closed forests at 30 m resolution. For dense forest canopies, the canopy could be captured but the ground surface could not be seen, so surface elevations from other sources would be needed to calculate the height of the canopy. A canopy height map with 30 m pixels was produced by subtracting national elevation dataset (NED) from the averaged elevation of synthesized point clouds, which exhibited spatial features of roads, forest edges and patches. The linear regression showed that the canopy height map had a good correlation with RH50 of LVIS data with a slope of 1.04 and R2 of 0.74 indicating that the canopy height derived from PRISM triplets can be used to estimate forest biomass at 30 m resolution.

Wenjian Ni; Kenneth Jon Ranson; Zhiyu Zhang; Guoqing Sun

2014-01-01T23:59:59.000Z

278

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

SciTech Connect

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

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

2011-10-01T23:59:59.000Z

279

Picosecond transient coherent anti-Stokes Raman spectroscopy of Rhodamine 560 in ethanol  

Science Journals Connector (OSTI)

Results of picosecond Raman scattering of the excited state of Rhodamine 560 are reported. Both two-and three-color transient spectroscopy are accomplished with a time resolution of...

Payne, Stephen A; Hochstrasser, R M

1986-01-01T23:59:59.000Z

280

Vlasov simulations of kinetic enhancement of Raman backscatter in laser fusion plasmas  

E-Print Network (OSTI)

Stimulated Raman scattering (SRS) is studied in plasmas relevant to inertial confinement fusion (ICF). The Eulerian Vlasov-Maxwell code ELVIS was developed and run for this purpose. Plasma waves are heavily Landau damped ...

Strozzi, D. J. (David J.)

2006-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Solar Energy Materials & Solar Cells 71 (2002) 511522 In situ Raman spectroscopy of the  

E-Print Network (OSTI)

Solar Energy Materials & Solar Cells 71 (2002) 511­522 In situ Raman spectroscopy. In this situation, a low energy excitation (e.g. visible light) is needed to excite an electron to a neighboring

Nabben, Reinhard

282

Enhancement of Raman Scattering for Silver Nanoparticles Located on Electrolessly Roughened Silicon  

Science Journals Connector (OSTI)

To study the effect of roughness of a supporting substrate to Raman enhancement, silver nanoparticles (AgNPs) were prepared on Si with different degrees of roughness. To roughen the...

Liou, Yen-Chen Maggie; Chen, Jiann-Yeu; Yang, Jyisy

2014-01-01T23:59:59.000Z

283

A study of heavy oil fractions by Fourier-transform near-infrared Raman spectroscopy  

Science Journals Connector (OSTI)

Oil fractions with a boiling-point step size of 20°C (300 to 560°C) for six different crude oils of Western Siberia have been studied by Fourier-transform Raman and Fourier-transform IR spectroscopy. Weak band...

A. Kh. Kuptsov; T. V. Arbuzova

2011-05-01T23:59:59.000Z

284

Isotope effect of the phonons mean free path in graphene by micro-Raman measurement  

Science Journals Connector (OSTI)

The isotope labeled graphene was synthesized in the concentration of 13C carbon atom in 1%, 25%, 50%, 75% and 99%. The isotope effect on the phonon behavior in graphene was investigated based on the micro-Raman a...

CanKun Zhang; QiongYu Li; Bo Tian…

2014-10-01T23:59:59.000Z

285

Raman excitation profile of the G band in single-chirality carbon nanotubes  

E-Print Network (OSTI)

We present in this work measurements of the Raman excitation profile of the high-energy phonons (G band) in single-chirality (n,m) semiconducting single-wall carbon nanotubes using more than 70 laser excitation energies, ...

Moura, L. G.

286

Resonance Raman spectroscopy in Si and C ion-implanted double-wall carbon nanotubes  

E-Print Network (OSTI)

The effect of 170 keV Si and 100 keV C ion bombardment on the structure and properties of highly pure, double-wall carbon nanotubes has been investigated using resonance Raman spectroscopy. The implantations were performed ...

Dresselhaus, Mildred

287

Spectral Collection of Polyethylene Pellets at nearly Cryogenic Temperature to Improve Selectivity of Raman Measurement  

SciTech Connect

Raman spectroscopy has been extensively used for analysis of diverse polymer samples. Normally, Raman spectral collection of samples is routinely performed at room temperature for convenience. However, the feasibility of improving spectral selectivity and the resulting quantitative accuracy, when samples are measured at nearly cryogenic temperature, has not been investigated. For this purpose, we attempted to measure the density of polyethylene (PE) pellets at cryogenic temperatures and the resulting accuracies were compared with that from room temperature measurement. Initially, each of 25 PE sample was allowed to cool down to cryogenic temperature and the corresponding Raman spectra were continuously collected while the temperature of sample increased. When the temperature of sample was at cryogenic temperature, the resulting band widths were narrower compared to those at room temperature, thereby improving the accuracy of density measurement. In overall, the proposed Raman scheme is simple and efficient; therefore, it could be further applied for analysis of other polymers.

Kim, Saetbyeol; Lee, Sanguk; Hwang, Jinyoung; Chung, Hoeil [Analytical Spectroscopy Lab, Department of Chemistry, Hanyang University, Seoul, 133-791 (Korea, Republic of)

2010-08-06T23:59:59.000Z

288

Infrared and Raman Spectra of a Sulfur-resistant Methanation Catalyst  

Science Journals Connector (OSTI)

The infrared and Raman spectra of a sulfur-resistant NiO/Cr2O3/MgSiO3 methanation catalyst are presented and compared to the spectra of the catalyst...

Stencel, J M; Bradley, E B; Brown, Fred R

1980-01-01T23:59:59.000Z

289

Surface-enhanced Raman spectroscopy at single-molecule scale and its implications in biology  

Science Journals Connector (OSTI)

...applications constituting areas in medicine, biology, environment and agriculture...surface-enhanced Raman spectroscopy|nanotechnology|hot spot|biological sciences...environmental science, basic sciences and medicine. The sensitivity of SM-SERS...

2013-01-01T23:59:59.000Z

290

The use of Surface Enhanced Raman Spectroscopy (SERS) for biomedical applications  

E-Print Network (OSTI)

Recent advances in nanotechnology and the biotechnology revolution have created an immense opportunity for the use of noble metal nanoparticles as Surface Enhanced Raman Spectroscopy (SERS) substrates for biological sensing and diagnostics...

Chowdhury, Mustafa Habib

2007-04-25T23:59:59.000Z

291

Raman spectroscopy study of heat-treated and boron-doped double wall carbon nanotubes  

E-Print Network (OSTI)

We performed Raman spectroscopy experiments on undoped and boron-doped double walled carbon nanotubes (DWNTs) that exhibit the “coalescence inducing mode” as these DWNTs are heat treated to temperatures between 1200 °C ...

Villalpando Paez, Federico

292

Fingerprint and high-wavenumber Raman spectroscopy in a human-swine coronary xenograft in vivo  

E-Print Network (OSTI)

Intracoronary Raman spectroscopy could open new avenues for the study and management of coronary artery disease due to its potential to measure the chemical and molecular composition of coronary atherosclerotic lesions. ...

Motz, Jason T.

293

From Gas Lasers and Tunable Raman Lasers to Quantum Cascade Lasers  

Science Journals Connector (OSTI)

I will describe my involvement in lasers from 1961 to the present, ecompassing high power carbon dioxide lasers, tunable spin-flip Raman lasers, and now high power CW room temperature...

Patel, Kumar

294

Zone folding effect in Raman G-band intensity of twisted bilayer graphene  

E-Print Network (OSTI)

The G-band Raman intensity is calculated for twisted bilayer graphene as a function of laser excitation energy based on the extended tight binding method. Here we explicitly consider the electron-photon and electron-phonon ...

Dresselhaus, Mildred

295

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

SciTech Connect

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.

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

1988-12-01T23:59:59.000Z

296

Multivariate analysis of Raman spectra for the identification of sulfates: Implications for ExoMars  

Science Journals Connector (OSTI)

...quantitative| Introduction Laser Raman spectroscopy...the quality of biodiesel fuels (Ghesti et al...Natural Sciences and Engineering Research Council...quantification of biodiesel in a progressive...methods. Energy and Fuels, 21, 2475-2480...

Guillermo Lopez-Reyes; Pablo Sobron; Catherine Lefebvre; Fernando Rull

297

Coherent anti-Stokes Raman scattering microscopy for quantitative characterization of mixing and flow in microfluidics  

Science Journals Connector (OSTI)

We present an optical, noninvasive and label-free approach to characterize flow profiles in microfluidic devices. Coherent anti-Stokes Raman scattering signals were used to map the...

Schafer, Dawn; Müller, Michiel; Bonn, Mischa; Marr, David W M; van Maarseveen, Jan; Squier, Jeff

2009-01-01T23:59:59.000Z

298

Raman spectra of size-selected silicon clusters and comparison with calculated structures  

Science Journals Connector (OSTI)

... ) and the agreement with experiment is much poorer. Other possible isomers with C3D and C2u symmetry6 8J2 are much higher in energy and also have many more Raman allowed lines ...

E. C. Honea; A. Ogura; C. A. Murray; Krishnan Raghavachari; W. O. Sprenger; M. F. Jarrold; W. L. Brown

1993-11-04T23:59:59.000Z

299

UV Resonance Raman Spectroscopy Using a New cw Laser Source: Convenience and Experimental Simplicity  

E-Print Network (OSTI)

into the spectrometer. We dem- onstrate the ability of this laser to excite Raman spectra of solid samples such as coal-liquid- alytical applications. Examples include studies of PAHs in coal-derived liquids4-~and in petroleum

Asher, Sanford A.

300

An infrared and Raman spectroscopy study of the corrosion products on carbon steel and weathering steel  

Science Journals Connector (OSTI)

Infrared and Raman spectroscopy are two analytical tools which have recently been applied to the study of corrosion products formed on metal surfaces. The two techniques are complementary and giv...

P. Fabis; C. Brown; T. Rockett; R. Heidersbach

1981-12-01T23:59:59.000Z

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Hybrid femtosecond/picosecond coherent anti-Stokes Raman scattering for gas-phase temperature measurements.  

E-Print Network (OSTI)

??Hybrid femtosecond/picosecond coherent anti-Stokes Raman scattering (fs/ps CARS) is employed for quantitative gas-phase temperature measurements in combustion processes and heated flows. In this approach, ultrafast… (more)

Miller, Joseph Daniel

2012-01-01T23:59:59.000Z

302

Stimulated Raman scattering from individual water and ethanol droplets at morphology-dependent resonances  

Science Journals Connector (OSTI)

Stimulated Raman scattering (SRS) from an individual liquid droplet (?30-?m radius) has been observed for H2O, D2O, and ethanol. The occurrence of a series of...

Snow, Judith B; Qian, Shi-Xiong; Chang, Richard K

1985-01-01T23:59:59.000Z

303

Fluid Phase Equilibria of Ethanol and Carbon Dioxide Mixtures with Concentration Measurements by Raman Spectroscopy  

Science Journals Connector (OSTI)

Phase equilibria data for the system ethanol/carbon dioxide for T = 313.15 K and pressures up to p = 7.9 MPa are presented. The measurements were made by Raman...

Stratmann, A; Schweiger, G

2002-01-01T23:59:59.000Z

304

Potential and limits of Raman spectroscopy for carotenoid detection in microorganisms: implications for astrobiology  

Science Journals Connector (OSTI)

...for a few cases where the current Raman spectroscopic approach does not allow discriminating structurally very similar carotenoids...S Liaaen-Jensen, and H Pfander (eds). 2004 Carotenoids handbook. Basel, Switzerland: Birkhauser. 5 Frank, HA , V Chynwat...

2014-01-01T23:59:59.000Z

305

Resonant stimulation of Raman scattering from single-crystal thiophene/phenylene co-oligomers  

SciTech Connect

Amplified Raman scattering was observed from single crystals of thiophene/phenylene co-oligomers (TPCOs). Under ns-pulsed excitation, the TPCO crystals exhibited amplified spontaneous emission (ASE) at resonant absorption wavelengths. With increasing excitation wavelength to the 0-0 absorption edge, the stimulated resonant Raman peaks appeared both in the 0-1 and 0-2 ASE band regions. When the excitation wavelength coincided with the 0-1 ASE band energy, the Raman peaks selectively appeared in the 0-2 ASE band. Such unusual enhancement of the 0-2 Raman scattering was ascribed to resonant stimulation via vibronic coupling with electronic transitions in the uniaxially oriented TPCO molecules.

Yanagi, Hisao, E-mail: yanagi@ms.naist.jp; Marutani, Yusuke; Matsuoka, Naoki; Hiramatsu, Toru; Ishizumi, Atsushi [Graduate School of Materials Science, Nara Institute of Science and Technology (NAIST), 8916-5 Takayama, Ikoma, Nara 630-0192 (Japan)] [Graduate School of Materials Science, Nara Institute of Science and Technology (NAIST), 8916-5 Takayama, Ikoma, Nara 630-0192 (Japan); Sasaki, Fumio [Electronics and Photonics Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan)] [Electronics and Photonics Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1 Umezono, Tsukuba, Ibaraki 305-8568 (Japan); Hotta, Shu [Department of Macromolecular Science and Engineering, Graduate School of Science and Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585 (Japan)] [Department of Macromolecular Science and Engineering, Graduate School of Science and Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585 (Japan)

2013-12-09T23:59:59.000Z

306

Dual-Remote Raman Technology for In-Situ Identification of Tank Waste - 13549  

SciTech Connect

A new Raman spectroscopic system for in-situ identification of the composition of solid nuclear tank waste is being developed by collaborative effort between Pacific Northwest National Laboratory (PNNL) and EIC Laboratories, Inc. The recent advancements in Raman technology allow probing the chemical composition of the tank waste without sample collection. In the newly tested configuration, the Raman probe is installed on the top of the tank riser and sends the incident laser beam to the bottom of the tank, 10 - 70 feet away. The returning light containing chemical information is collected by the Raman probe and is transmitted via fiber optic cable to the spectrometer located outside the tank farm area. This dual remote technology significantly expands currently limited options for the safe rapid in-situ identification of the solid tank waste needed for the retrieval decisions. The developed Raman system was extensively tested for acceptability prior to tank farm deployment. This testing included calibration of the system with respect of the distance between the Raman probe and the sample, incident laser beam angle, and presence of the optical interferences. The Raman system was successfully deployed on Tank C-111 at the US DOE Hanford site. As the result of this deployment, the composition of the hardpan at the bottom of C-111 tank was identified. Further development of the dual-remote Raman technology will provide a significant safety enhancement eliminating the potential of personnel radiation exposure associated with the grab sample collection and expands options of the rapid and cost-effective in-situ chemical analysis of the tank waste. (authors)

Bryan, Sam; Levitskaia, Tatiana; Lines, Amanda; Smith, Frannie; Josephson, Gary [Pacific Northwest National Laboratory, Richland WA, 99352 (United States)] [Pacific Northwest National Laboratory, Richland WA, 99352 (United States); Bello, Job [EIC, Inc., Norwood, MA 02062 (United States)] [EIC, Inc., Norwood, MA 02062 (United States)

2013-07-01T23:59:59.000Z

307

Raman-Active Lattice Vibrations of the Commensurate Superlattic in 2H-TaSe2  

Science Journals Connector (OSTI)

Raman spectra have been obtained on 2H-TaSe2 at room temperature and in the commensurate charge-density-wave, superlattice state. At low temperatures six new low frequency modes are seen having symmetries consistent only with a symmetric, three-charge-density wave. A microscopic model of the lattice dynamics of this state is fitted to the four strongest new Raman lines. These are assigned to amplitude and phase modes of the charge-density wave.

John A. Holy, Miles V. Klein, W. L. McMillan, and S. F. Meyer

1976-10-25T23:59:59.000Z

308

Raman spectroscopy for characterization of annealing of ion-implanted InP  

SciTech Connect

Raman spectroscopy has been used as a noncontacting, nondestructive tool to evaluate the properties of Si/sup +/- and Be/sup +/- implanted InP samples annealed at temperatures ranging from 600 to 750C using phosphosilicate glass (PSG) as the encapsulant. Carrier activation, carrier mobility and recovery of damage as a function of anneal temperature obtained from analysis of Raman data agree very well with independent electrical measurements.

Myers, D.R.; Gourley, P.L.; Vaidyanathan, K.V.; Dunlap, H.L.

1982-01-01T23:59:59.000Z

309

X-ray Raman compression via two-stream instability in dense plasmas  

E-Print Network (OSTI)

A Raman compression scheme suitable for x-rays, where the Langmuir wave is created by an intense beam rather than the pondermotive potential between the seed and pump pulses, is proposed. The required intensity of the seed and pump pulses enabling the compression could be mitigated by more than a factor of 100, compared to conventionally available other Raman compression schemes. The relevant wavelength of x-rays ranges from 1 to 10 nm.

S. Son; Sung Joon Moon

2011-03-27T23:59:59.000Z

310

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

SciTech Connect

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.

Reich, F.R.

1996-09-27T23:59:59.000Z

311

OH/F substitution in topaz studied by Raman spectroscopy  

Science Journals Connector (OSTI)

The Raman band related to the stretching mode of hydroxyl (OH-) centered at about 3650 cm-1 is investigated in several natural specimens of topaz single crystals with a composition Al2SiO4(OHxF(1-x))2 within a wide range of OH mole fractions (x). The analysis of the OH band shape shows that its asymmetry is due to an unresolved splitting in two peaks, centered at 3639 and 3647 cm-1, labeled as OHA and OHB, respectively. Although the asymmetry is drastically different for OH-rich and OH-poor topaz, we show that this is only caused by the change of the OHA/OHB intensity ratio with the total OH concentration. In order to explain the splitting of the OH band, we suggest a model which involves a reduction of the local symmetry from D2h16 to C2v9, resulting in two types of physically nonequivalent F sites (A and B) where the OH/F substitution can occur. Both sites have C1 site symmetries and a multiplicity of 4.

M. V. B. Pinheiro; C. Fantini; K. Krambrock; A. I. C. Persiano; M. S. S. Dantas; M. A. Pimenta

2002-02-20T23:59:59.000Z

312

Measuring depth profiles of residual stress with Raman spectroscopy  

SciTech Connect

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.

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

1988-12-01T23:59:59.000Z

313

Doppler effects in resonant x-ray Raman scattering  

Science Journals Connector (OSTI)

Theory for Doppler effects in resonant x-ray Raman scattering (RXS) is presented. It is shown that the “electron” Doppler effect is important in nonradiative RXS for decay transitions between continuum nuclear states lying above the dissociation threshold, and that the averaging of the RXS cross section over molecular orientations can lead to strong non-Lorentzian broadenings of the atomiclike resonances. The Doppler effect is found to give a unique possibility to distinguish dissociating identical atoms, because different peaks correspond to atoms with opposite Doppler shifts. Spectral features of the atomiclike profile are predicted and analyzed. Strong oscillations of the RXS cross section will occur as a consequence of the interference of the Auger electrons. Due to the Doppler effect and the interference, the atomiclike profile can be associated with supernarrow spectral features, the width of which goes below the lifetime broadening and is practically independent of the spectral distribution of the incident radiation. As another consequence of the oscillations and strong anisotropy caused by the interference, we predict parity selection rules for Auger decay transitions in both bound and dissociative systems. The corresponding experiments can be realized by measurements of resonant Auger of surface adsorbed molecules and for molecules by the electron-ion coincidence technique.

Faris Gel’mukhanov; Hans Ågren; Pawe? Sa?ek

1998-04-01T23:59:59.000Z

314

Characterization of Crude Oil Products Using Data Fusion of Process Raman, Infrared, and Nuclear Magnetic Resonance (NMR) Spectra  

Science Journals Connector (OSTI)

Process Raman, infrared (IR), and nuclear magnetic resonance (NMR) analyses are currently being performed in industrial settings for the monitoring of large scale reactions. These...

Dearing, Thomas I; Thompson, Wesley J; Rechsteiner, Carl E; Marquardt, Brian J

2011-01-01T23:59:59.000Z

315

Micro-Raman spectroscopic study of nanolaminated Ti{sub 5}Al{sub 2}C{sub 3}  

SciTech Connect

Micro-Raman spectroscopic study and lattice dynamics calculations were conducted to study a recently identified layered ternary carbide, Ti{sub 5}Al{sub 2}C{sub 3}. The experimental Raman shifts were remarkably consistent with the calculated values. Polarized Raman spectrum was collected in the polycrystalline sample, which confirmed the theoretical symmetry assignment of the Raman modes. In addition, the atomic vibrations of the peaks at 192?cm{sup ?1}, 311?cm{sup ?1}, and 660?cm{sup ?1} were identified to be the combination of the counterparts in Ti{sub 2}AlC and Ti{sub 3}AlC{sub 2}.

Zhang, H.; Li, Z. J. [Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016 (China); University of Chinese Academy of Sciences, Beijing 100049 (China); Wang, X. H. [Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, 72 Wenhua Road, Shenyang 110016 (China); Xiang, H. M.; Zhou, Y. C, E-mail: yczhou714@gmail.com [Science and Technology of Advanced Functional Composite Laboratory, ARIMPT, No.1 South Dahongmen Road, Beijing 100076 (China)

2014-03-31T23:59:59.000Z

316

Raman spectroscopic and mass spectrometric investigations of the hydrogen isotopes and isotopically labelled methane  

SciTech Connect

Suitable analytical methods must be tested and developed for monitoring the individual process steps within the fuel cycle of a fusion reactor and for tritium accountability. The utility of laser-Raman spectroscopy accompanied by mass spectrometry with an Omegatron was investigated using the analysis of all hydrogen isotopes and isotopically labeled methanes as an example. The Omegatron is useful for analyzing all hydrogen isotopes mixed with the stable helium isotopes. The application of this mass spectrometer were demonstrated by analyzing mixtures of deuterated methanes. In addition, it was employed to study the radiochemical Witzbach exchange reaction between tritium and methanes. A laser-Raman spectrometer was designed for analysis of tritium-containing gases and was built from individual components. A tritium-compatible, metal-sealed Raman cuvette having windows with good optical properties and additional means for measuring the stray light was first used successfully in this work. The Raman spectra of the hydrogen isotopes were acquired in the pure rotation mode and in the rotation-vibration mode and were used for on. The deuterated methanes were measured by Raman spectroscopy, the wavenumbers determined were assigned to the corresponding vibrations, and the wavenumbers for the rotational fine-structure were summarized in tables. The fundamental Vibrations of the deuterated methanes produced Witzbach reactions were detected and assigned. The fundamental vibrations of the molecules were obtained with Raman spectroscopy for the first time in this work. The @-Raman spectrometer assembled is well suited for the analysis of tritium- containing gases and is practical in combination with mass spectrometry using an Omegatron, for studying gases used in fusion.

Jewett, J.R., Fluor Daniel Hanford

1997-02-24T23:59:59.000Z

317

Identification of minerals and meteoritic materials via Raman techniques after capture in hypervelocity impacts on aerogel  

SciTech Connect

For this study, an extensive suite of mineral particles analogous to components of cosmic dust were tested to determine if their Raman signatures can be recognized after hypervelocity capture in aerogel. The mineral particles were mainly of greater than 20 micrometers in size and were accelerated onto the silica aerogel by light gas gun shots. It was found that all the individual minerals captured in aerogel could be subsequently identified using Raman (or fluorescent) spectra. The beam spot size used for the laser illumination was of the order of 5 micrometers, and in some cases the captured particles were of a similar small size. In some samples fired into aerogel there was observed a shift in the wavenumbers of some of the Raman bands, a result of the trapped particles being at quite high temperatures due to heating by the laser. Temperatures of samples under laser illumination were estimated from the relative intensities of Stokes and anti-Stokes Raman bands, or, in the case of ruby particles, from the wavenumber of fluorescence bands excited by the laser. It was found that the temperature of particles in aerogel varied greatly, dependent upon laser power and the nature of the particle. In the worst case, some particles were shown to have temperatures in the 500-700 C range at a laser power of about 3 mW at the sample. However most of the mineral particles examined at this laser power had temperatures below 200 C. This is sufficiently low a temperature not to damage most materials expected to be found captured in aerogel in space. In addition, selected meteorite samples were examined to obtain Raman signatures of their constituent minerals and were then shot into aerogel. It was possible to find several Raman signatures after capture in aerogel and obtain a Raman map of a whole grain in situ in the aerogel. Finally, a Raman analysis was carried out of a particle captured in aerogel in space and carbonaceous material identified. In general therefore it is concluded that Raman analysis is indeed well suited for an in-situ analysis of micrometer sized non-terrestrial materials captured in aerogel.

Burchell, M J; Mann, J; Creighton, J A; Kearsley, A; Graham, G A; Esposito, A P; Franchi, I A; Westphal, A J; Snead, C

2004-10-04T23:59:59.000Z

318

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

SciTech Connect

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 (?c-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 ?c-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 ?c-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.

Ledinský, M., E-mail: ledinsky@fzu.cz [Laboratory of Nanostructures and Nanomaterials, Institute of Physics, Academy of Sciences of the Czech Republic, v. v. i., Cukrovarnická 10, 162 00 Prague (Czech Republic); Photovoltaics and Thin Film Electronics Laboratory, Institute of Microengineering (IMT), École Polytechnique Fédérale de Lausanne (EPFL), Rue de la Maladière 71b, CH-2000 Neuchâtel (Switzerland); Moulin, E.; Bugnon, G.; Meillaud, F.; Ballif, C. [Photovoltaics and Thin Film Electronics Laboratory, Institute of Microengineering (IMT), École Polytechnique Fédérale de Lausanne (EPFL), Rue de la Maladière 71b, CH-2000 Neuchâtel (Switzerland); Ganzerová, K.; Vetushka, A.; Fejfar, A. [Laboratory of Nanostructures and Nanomaterials, Institute of Physics, Academy of Sciences of the Czech Republic, v. v. i., Cukrovarnická 10, 162 00 Prague (Czech Republic)

2014-09-15T23:59:59.000Z

319

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

SciTech Connect

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.

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

1988-12-01T23:59:59.000Z

320

In situ Raman spectroscopy of lithium electrode surface in ambient temperature lithium secondary battery. Final report  

SciTech Connect

Raman spectroscopy was used to characterize surface layers on lithium electrodes in different solvents such as propylene carbonate (PC), dimethyl carbonate (DMC), diethyl carbonate (DEC), and polyethylene glycol 400 dimethyl ether (PEG400DME). Both DMC and DEC were used singly, and also mixed with either methyl acetate (MA) or methyl formate (MF). The Raman spectra showed that passive films formed on the Li surface in different solvents may have different chemical structures, which changed during the charging and discharging processes. Raman spectroscopy was also applied to characterize zinc electrode surfaces in alkaline solutions. The results suggested that ZnO and Zn(OH){sub 2} formed on the Zn electrode when a passive potential was applied. A solid film of fullerene C{sub 60}, which could be used as a cathode in Li rechargeable batteries, was examined in the PEG400DME solution by both electrochemical and Raman spectroscopy. Cyclic voltammograms (CVs) showed five redox peaks which suggested the formation of C{sub 60}{sup {minus}}, C{sub 60}{sup 2{minus}}, C{sub 60}{sup 3{minus}}, C{sub 60}{sup 4{minus}}, and C{sub 60}{sup 5{minus}}. Raman spectra obtained from a thin C{sub 60} film indicated that the thin fulleride film dissolved in the PEG400DME/LiClO{sub 4} solution at negative potentials.

Tachikawa, Hiroyasu [Jackson State Univ., MS (United States). Dept. of Chemistry

1992-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Raman study of some melilites in crystalline and glassy states  

SciTech Connect

Raman spectra are reported for crystalline akermanite, hardystonite, gehlenite, sodium melilite and for glasses of corresponding compositions. The spectra of melilites are dominated by the vibrational modes of pyrosilicate units and not by the sheet-like structure formed by interconnected TMO{sub 4} tetrahedra. The frequency of {nu}{sub s}(T-O-T), the symmetric stretching mode of the bridging oxygen in the pyrosilicate unit, is directly related to the angle of the T-O-T linkage. The symmetric stretching bands of nonbridging oxygens {nu}{sub s}(T-O{sup {minus}}) appear in the spectral range characteristic of T-O{sup {minus}} stretching in pyrosilicate units. The intensity of the {nu}{sub s}(T-O{sup {minus}}) band is, however, affected by the presence of Al{sup 3+} in tetrahedral sites adjacent to the pyrosilicate units. The lowering of the intensities of nonbridging oxygen stretching bands in the spectra of Geh and SM is attributed to a change in the degree of covalency of T-O{sup {minus}} bonds in the pyrosilicate unit resulting from substitution of Al{sup 3+} for Mg{sup 2+} in the adjacent tetrahedral sites. Comparison of the spectra of crystals with glasses indicates that most Al{sup 3+} ions act as network-forming cations, whereas Mg{sup 2+}, Zn{sup 2+} and Ca{sup 2+} retain their role as network modifiers. Spectra of glasses of Ak and Har composition show SiO{sub 4}{sup 4{minus}} and Si{sub 2}O{sub 7}{sup 6{minus}} bands, indicating a redistribution of silicate species among monomer, dimer, trimer and tetramer chains. Glasses of Geh and SM compositions are more highly polymerized than their respective crystalline counterparts because of the role of Al{sup 3+} as network-forming cations in the glass structures.

Sharma, S.K.; Matson, D.W. (Hawaii Institute of Geophysics, Honolulu (USA)); Yoder, H.S. Jr. (Geophysical Lab., Washington, DC (USA))

1988-08-01T23:59:59.000Z

322

Development and Deployment of a Compact Eye-safe Scanning Differential Absorption Lidar (DIAL) for Spatial Mapping of Carbon Dioxide for MVA at Geologic Carbon Sequestration Sites  

NLE Websites -- All DOE Office Websites (Extended Search)

Deployment of a Deployment of a Compact Eye-safe Scanning Differential Absorption Lidar (DIAL) for Spatial Mapping of Carbon Dioxide for MVA at Geologic Carbon Sequestration Sites Description Through its core research and development program administered by the National Energy Technology Laboratory (NETL), the U.S. Department of Energy (DOE) emphasizes monitoring, verification, and accounting (MVA), as well as computer simulation, of possible carbon dioxide (CO 2 ) leakage at CO 2

323

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

DOE Patents (OSTI)

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.

Myrick, Michael L. (Livermore, CA); Angel, Stanley M. (Livermore, CA)

1993-01-01T23:59:59.000Z

324

Pulsed-laser-excited Raman spectra of shock-compressed triaminotrinitrobenzene  

SciTech Connect

Pulsed-laser-excited Raman scattering methods have been used to examine sustained shock compression of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) at an optical window interface. Records of vibrational frequency shifts and line shape changes have been obtained under variable and well-controlled shock loading using a 63-mm-diameter compressed gas gun to provide a planar impact geometry. To facilitate interpretation of the shock data. Raman spectra of TATB samples at elevated temperatures and ambient pressure have also been acquired. Raman modes identified with the nitro and amino groups in TATB exhibit complex behavior arising from interactions associated with the extensive intra- and intermolecular hydrogen bonding network in this material. The distinct (and frequently competing) effects of pressure and temperature on these modes are discussed in relation to the known insensitivity of TATB to shock initiation. 20 refs., 9 figs.

Trott, W.M.; Renlund, A.M. (Sandia National Labs., Albuquerque, NM (USA))

1989-01-01T23:59:59.000Z

325

Relationship between coking coal quality and its micro-Raman spectral characteristics  

Science Journals Connector (OSTI)

Abstract Micro-Raman spectroscopy examination of 20 samples of coking coals (Rr = 0.84–1.43%) was performed. Spectral parameters were correlated with the basic rank and technological properties of coals. The G band FWHM and the AG/AALL ratio decrease with the volatile matter content (Vdaf) decrease and the all maceral reflectance scan (Rscan) value increase. The correlations between these parameters are stronger than those, between the G band FWHM and the AG/AALL ratio, and the mean random vitrinite reflectance (Rr). Coking properties are weakly related to the Raman spectral characteristics of coal. Based on the Raman parameters G band FWHM and the AG/AALL ratio, it may be possible to evaluate the volatile matter content (Vdaf) and the all maceral reflectance scan (Rscan) value for coking coals.

Rafa? Morga; Iwona Jelonek; Krystyna Kruszewska

2014-01-01T23:59:59.000Z

326

Application of a multivariate technique to Raman spectra for quantification of body chemicals  

SciTech Connect

Raman spectroscopy is a highly specific technique for the identification of molecules by way of the associated characteristic spectra. The aim of this feasibility study is to assess the combination of the multivariate calibration technique of Partial Least-Squares with Raman spectroscopy for the estimation of glucose, lactic acid, and urea concentrations in the presence of each other in a water substrate. The instrument is a CCD-based Raman spectrometer utilizing the 514.5 nm argon laser line. The estimates for the analyte concentrations yielded a standard deviation of concentration residuals of 20.71 mg/dL for glucose, 12.92 mg/dL for lactic acid, and 19.07 mg/dL for urea. 16 refs., 2 figs., 3 tabs.

Goetz, M.J. Jr.; Cote, G.L. [Texas A& M Univ., College Station, TX (United States)] [Texas A& M Univ., College Station, TX (United States); Erckens, R.; March, W.; Motamedi, M. [Univ. of Texas Medical Branch, Galveston, TX (United States)] [Univ. of Texas Medical Branch, Galveston, TX (United States)

1995-07-01T23:59:59.000Z

327

Synthesis of few layer graphene by direct exfoliation of graphite and a Raman spectroscopic study  

SciTech Connect

The exfoliation of graphene from pristine graphite in a liquid phase was achieved successfully via sonication followed by centrifugation method. Ultraviolet–visible (UV–vis) spectra of the obtained graphene dispersions at different exfoliation time indicated that the concentration of graphene dispersion increased markedly with increasing exfoliation time. The sheet-like morphology of the exfoliated graphene was revealed by Scanning Electron Microscopy (SEM) image. Further, the morphological change in different exfoliation time was investigated by Atomic Force Microscopy (AFM). A complete structural and defect characterization was probed using micro-Raman spectroscopic technique. The shape and position of the 2D band of Raman spectra revealed the formation of bilayer to few layer graphene. Also, Raman mapping confirmed the presence of uniformly distributed bilayer graphene sheets on the substrate.

Gayathri, S.; Jayabal, P.; Ramakrishnan, V., E-mail: vr.optics1@gmail.com [Department of Laser Studies, School of Physics, Madurai Kamaraj University, Madurai-625021, India. (India); Kottaisamy, M. [Department of Chemistry, Thiagarajar College of Engineering, Madurai-625015, India. (India)] [Department of Chemistry, Thiagarajar College of Engineering, Madurai-625015, India. (India)

2014-02-15T23:59:59.000Z

328

Raman Images of a Single Molecule in a Highly Confined Plasmonic Field  

E-Print Network (OSTI)

Under the local plasmonic excitation, the Raman images of a single molecule can now reach sub-nm resolution. We report here a general theory to describe the interaction between a molecule and a highly confined plasmonic field. It is shown that when the spatial distribution of the plasmonic field is comparable with the size of the molecule, the plasmonic field needs to be treated quantum mechanically. The resonant Raman image of a molecule is found to be strongly associated with the density of the electronic transition. In combination with the first principles calculations, the simulated Raman image of a porphyrin derivative adsorbed on the silver surface nicely reproduces its experimental counterpart. It reveals that the quantum nature of the highly confined plasmonic field offers a new way to modify the wavefunction of the molecule. The present theory provides the basic framework for describing linear and nonlinear responses of molecules under the non-uniform quantized field.

Duan, Sai; Ji, Yongfei; Shao, Jiushu; Luo, Yi

2014-01-01T23:59:59.000Z

329

DOI: 10.1002/chem.201002027 Surface-Enhanced Raman Scattering of Single-and Few-Layer Graphene by  

E-Print Network (OSTI)

DOI: 10.1002/chem.201002027 Surface-Enhanced Raman Scattering of Single- and Few-Layer Graphene*[a] Introduction Raman spectroscopy has been utilized as a powerful tool for the characterization of graphene and any defects in the graphene.[1] A Si substrate with a metal oxide layer of a specific thick- ness has

Kim, Bongsoo

330

Theory of Two-Magnon Raman Scattering in Iron Pnictides and Chalcogenides  

SciTech Connect

Although the parent iron-based pnictides and chalcogenides are itinerant antiferromagnets, the use of local moment picture to understand their magnetic properties is still widespread. We study magnetic Raman scattering from a local moment perspective for various quantum spin models proposed for this new class of superconductors. These models vary greatly in the level of magnetic frustration and show a vastly different two-magnon Raman response. Light scattering by two-magnon excitations thus provides a robust and independent measure of the underlying spin interactions. In accord with other recent experiments, our results indicate that the amount of magnetic frustration in these systems may be small.

Chen, C. C.

2011-08-15T23:59:59.000Z

331

High-resolution inverse Raman and resonant-wave-mixing spectroscopy  

SciTech Connect

These research activities consist of high-resolution inverse Raman spectroscopy (IRS) and resonant wave-mixing spectroscopy to support the development of nonlinear-optical techniques for temperature and concentration measurements in combustion research. Objectives of this work include development of spectral models of important molecular species needed to perform coherent anti-Stokes Raman spectroscopy (CARS) measurements and the investigation of new nonlinear-optical processes as potential diagnostic techniques. Some of the techniques being investigated include frequency-degenerate and nearly frequency-degenerate resonant four-wave-mixing (DFWM and NDFWM), and resonant multi-wave mixing (RMWM).

Rahn, L.A. [Sandia National Laboratories, Livermore, CA (United States)

1993-12-01T23:59:59.000Z

332

Characterization of the surface properties of xylan by FT-Raman spectroscopy and wicking technique  

Science Journals Connector (OSTI)

Using FT-Raman spectroscopy, column wicking technique and the equations of Washburn as well as van Oss et al., the surface properties of xylan, the main component in hemicelluloses, has been characterized and estimated. Raman spectrum showed that xylan has been structured by acetyl group and methyl-bonded glucurono group. Obtained results show that the surface free energy of xylan is higher in comparison with literature reported values for cellulose because the former has a larger Lifshitz–van der Waals component than the latter. However, xylan has been found to have very smaller polarity and orientation data than that of cellulose.

Qing Shen; Lei Zhong; Jian-Feng Hu

2004-01-01T23:59:59.000Z

333

Observation of Stimulated Raman Scattering from 20-psec Laser-Produced Plasmas  

Science Journals Connector (OSTI)

Raman scattering spectra obtained with 20-psec 1.064-?m laser pulses incident at 45° on nickel-foil targets show an intensity-dependent red shift relative to the subharmonic of the laser frequency. In conjunction with temperature data deduced from x-ray measurements, the results imply a change from the absolute to the convective instability with increasing intensity. The observation of Raman scattering is correlated with the appearance of a high-energy tail in the x-ray spectrum above 100 keV.

K. A. Nugent and B. Luther-Davies

1982-12-27T23:59:59.000Z

334

Manipulation of the Raman process via incoherent pump, tunable intensity, and phase control  

E-Print Network (OSTI)

Manipulation of the Raman process via incoherent pump, tunable intensity, and phase control Li-Gang Wang,1,2,3 Sajid Qamar,1 Shi-Yao Zhu,1,2,3 and M. Suhail Zubairy1,4,5 1Centre for Quantum Physics, COMSATS Institute of Information Technology..., Texas 77845, USA 5Texas A&M University at Qatar, P.O. Box 23874, Education City, Doha, Qatar #1;Received 14 May 2007; published 18 March 2008#2; We present a proposal to manipulate the Raman process via incoherent pump, tunable intensity, and phase...

Wang, Li-Gang; Qamar, Sajid; Zhu, Shi-Yao; Zubairy, M. Suhail

2008-01-01T23:59:59.000Z

335

Infrared and Raman spectoscopy study, of the corrosion products, on carbon steel and weathering steel  

SciTech Connect

Infrared and Raman spectroscopy are two analytical tools which have recently been applied to the study of corrosion products formed on metal surfaces. The two techniques are complementary and give structural information similar to that provided by X-ray and electron diffraction. However, they are unlike X-ray and electron diffraction in that they do not require crystalline solids to provide structural identification. Wheathering steels are an important class of metals which form noncrystalline corrosion products. This report describes infrared and Raman spectra obtained from a weathering steel and compares the spectra to those obtained for carbon steel which had been exposed to the same environment.

Fabis, P.; Brown, T.; Heidersbach, R.; Rockett, T.

1981-01-01T23:59:59.000Z

336

Characterization of Irradiated Starches by Using FT-Raman and FTIR Spectroscopy  

Science Journals Connector (OSTI)

Degradation of starch polymers resulting in decreased viscosity and increased water solubility, and increased acidity with increasing radiation doses are potential changes observed in irradiated starches. ... FT-Raman spectra were obtained using a Nicolet 870 spectrometer with the Raman module 32B (Madison, WI) and Nd:YAG laser operating at 1064 nm with a maximum power of 2 W. The system was equipped with an InGaAs (Indium?Gallium Arsenide) detector, XT-KBr beam-splitter with 180° reflective optics, and a fully motorized sample position adjustment feature. ...

Ramazan Kizil; Joseph Irudayaraj; Koushik Seetharaman

2002-06-07T23:59:59.000Z

337

Raman Spectroscopy of SiO2 Glass at High Pressure  

Science Journals Connector (OSTI)

A new technique has been developed for optical studies of amorphous solids to very high pressures. Raman spectra of SiO2 glass measured at 8 GPa indicate a significant reduction in the width of the Si-O-Si angle distribution, which has been associated with a number of anomalous properties of silica glass under ambient conditions. Between 8 and ? 30 GPa irreversible changes in the Raman spectrum occur that are consistent with a shift in ring statistics in densified glass. The spectra suggest a breakdown in intermediate-range order at higher pressure.

R. J. Hemley; H. K. Mao; P. M. Bell; B. O. Mysen

1986-08-11T23:59:59.000Z

338

Comment on 'Stimulated Raman scattering of laser from periodically spaced nanoparticles' [Phys. Plasmas 16, 093106 (2009)  

SciTech Connect

Parashar [Phys. Plasmas 16, 093106 (2009)] studied the Raman backscattering of electromagnetic waves from nanoparticle lattice. We have demonstrated that the uncoupled dispersion curves have incorrect cutoff frequencies and the electromagnetic dispersion curves do not have correct asymptotic behavior at large frequencies. It has been shown that Parashar obtained an incorrect diagram of the growth rate for which the pump wave frequency goes below the cutoff frequency of the electromagnetic wave. Correct diagrams for the Raman backscattering as well as forward scattering are presented. It has been shown that backscattering has a larger maximum growth rate. We also found no instability if scattered radiation belongs to the lower branch of the dispersion curves.

Maraghechi, B. [Department of Physics, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of); Chakhmachi, A. [Plasma Physics and Nuclear Fusion Research School, Nuclear Science and Technology Research Institute, Atomic Energy Organization of Iran, P.O. Box 14155-1339, Tehran (Iran, Islamic Republic of)

2010-08-15T23:59:59.000Z

339

Indian Academy of Sciences C V Raman Avenue, Sadashivanagar, Bangalore 560 080  

E-Print Network (OSTI)

System' The Indian Academy of Sciences is in need of `Multi-point Video Conference SystemIndian Academy of Sciences C V Raman Avenue, Sadashivanagar, Bangalore 560 080 No. : IASc/ /13-14 Dated: 23-12-2013 Sub: Inviting Tenders for the `Supply and installation of Multi-point Video Conference

Joshi, Yogesh Moreshwar

340

Probing IrTe2 crystal symmetry by polarized Raman scattering  

Science Journals Connector (OSTI)

Polarized Raman scattering measurements on IrTe2 single crystals carried out over the 15–640 K temperature range, and across the structural phase transition, reveal different insights regarding the crystal symmetry. In the high temperature regime three Raman active modes are observed at all of the studied temperatures above the structural phase transition, rather than two as predicted by the factor group analysis for the assumed P3¯m1 symmetry. This indicates that the actual symmetry of the high temperature phase is lower than previously thought. The observation of an additional Eg mode at high temperature can be explained by doubling of the original trigonal unit cell along the c axis and within the P3¯c1 symmetry. In the low temperature regime (below 245 K) the other Raman modes appear as a consequence of the symmetry lowering phase transition and the corresponding increase of the primitive cell. All of the modes observed below the phase transition temperature can be assigned within the monoclinic crystal symmetry. The temperature dependence of the Raman active phonons in both phases is mainly driven by anharmonicity effects. The results call for reconsideration of the crystallographic phases of IrTe2.

N. Lazarevi?; E. S. Bozin; M. Š?epanovi?; M. Opa?i?; Hechang Lei (???); C. Petrovic; Z. V. Popovi?

2014-06-16T23:59:59.000Z

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

hal-00276997,version1-5May2008 Raman spectra of misoriented bilayer graphene  

E-Print Network (OSTI)

hal-00276997,version1-5May2008 Raman spectra of misoriented bilayer graphene P. Poncharal1 , A layer graphene with a bilayer in which the two layers are arbitrarily misoriented. The profiles of the 2 of the electronic structures of single layer graphene and misoriented bilayer graphene. Another new aspect

342

Atomic force microscope with combined FTIR-Raman spectroscopy having a micro thermal analyzer  

DOE Patents (OSTI)

An atomic force microscope is provided that includes a micro thermal analyzer with a tip. The micro thermal analyzer is configured for obtaining topographical data from a sample. A raman spectrometer is included and is configured for use in obtaining chemical data from the sample.

Fink, Samuel D. (Aiken, SC); Fondeur, Fernando F. (North Augusta, SC)

2011-10-18T23:59:59.000Z

343

Coherent anti-stokes Raman spectroscopy system for point temperature and major species concentration measurement  

SciTech Connect

The Coherent anti-Stokes Raman Spectroscopy system (CARS) has been developed as a laser-based, advanced, combustion-diagnostic technique to measure temperature and major species concentration. Principles of operation, description of the system and its capabilities, and operational details of this instrument are presented in this report.

Singh, J.P.; Yueh, Fang-Yu

1993-10-01T23:59:59.000Z

344

Anodic Behavior of Ti in KOH Solutions Ellipsometric and Micro-Raman Spectroscopy Studies  

E-Print Network (OSTI)

Anodic Behavior of Ti in KOH Solutions Ellipsometric and Micro-Raman Spectroscopy Studies A. Prusi of South Carolina, Columbia, South Carolina 29208, USA Anodic formation of oxide films on titanium surfaces of refraction of anodic oxide films have been determined. The voltage at which the oxide film breaks down

Popov, Branko N.

345

In Vivo Metabolic Fingerprinting of Neutral Lipids with Hyperspectral Stimulated Raman Scattering Microscopy  

Science Journals Connector (OSTI)

Coherent anti-Stokes Ramam scattering (CARS) and Stimulated Raman scattering (SRS) largely overcome this problem by improving the imaging sensitivity by 4–5 orders of magnitude. ... (25) The yeast mutant strains—FYS252 (lacking Are1 and Are2) and FYS242 (lacking Dga1 and Lro1)—have defective SE and TAG synthesis, respectively. ...

Dan Fu; Yong Yu; Andrew Folick; Erin Currie; Robert V. Farese, Jr.; Tsung-Huang Tsai; Xiaoliang Sunney Xie; Meng C. Wang

2014-05-28T23:59:59.000Z

346

Raman and infrared studies of superlattice formation in TiSe2  

Science Journals Connector (OSTI)

Raman and far-infrared reflectivity spectra have been obtained for both stoichiometric and nonstoichiometric TiSe2 above and below the transition temperatures corresponding to formation of the 2a0×2c0 superlattice. In the normal phase above Tc Raman-active lines are observed at 134 cm-1 (Eg) and at 195 cm-1 (A1g). Normal-incidence reflectivity shows a single Eu mode at 137 cm-1 superimposed upon a highly damped Drude background. Below Tc, strong new Eg and A1g Raman lines appear together with several weaker lines and bands. Likewise, a Kramers-Kronig analysis of the low-temperature infrared data shows many new optically active lattice modes. We have predicted the number and symmetry of all even and odd modes which are folded into the center of the original Brillouin zone from the points A, L, and M at the zone surface due to the periodic lattice distortion. Reasonable agreement is found for the suggested superlattice, although some weak lines in both the low-temperature Raman and infrared data are unexplained.

J. A. Holy, K. C. Woo, M. V. Klein, and F. C. Brown

1977-10-15T23:59:59.000Z

347

Murchison presolar carbon grains of different density fractions: A Raman spectroscopic perspective  

E-Print Network (OSTI)

for inorganic sp2 -bonded carbon. Based on their D/G intensity ratios, those grains were grouped.1), "glassy carbon" (D/G > 1.1), and "unusual sp2 -bonded graphitic car- bon" (with extremely intense 2ndMurchison presolar carbon grains of different density fractions: A Raman spectroscopic perspective

348

Excitonic effects of photoluminescence and resonance Raman intensity of single wall carbon nanotubes  

E-Print Network (OSTI)

1 Excitonic effects of photoluminescence and resonance Raman intensity of single wall carbon been widely used for the optical characterization of single wall carbon nanotubes (SWNTs) since the intensity and energy of PL and RRS depend on the diameter and chirality of SWNTs. The optical absorption

Maruyama, Shigeo

349

Raman fibre lasers emitting at a wavelength above 2 {mu}m  

SciTech Connect

Single-mode Raman fibre lasers emitting a few hundreds of millwatts at wavelengths of 2.0 and 2.2 {mu}m are built for the first time. Laser emission was amplified in a fibre with a germanium dioxide core and a silica cladding pumped by an Er/Yb-doped fibre laser. (lasers)

Dianov, Evgenii M; Bufetov, Igor' A; Mashinsky, V M; Neustruev, V B; Medvedkov, O I; Shubin, Aleksei V; Mel'kumov, Mikhail A [Fiber Optics Research Center, Russian Academy of Sciences, Moscow (Russian Federation); Gur'yanov, A N; Khopin, V F; Yashkov, M V [Institute of Chemistry of High-Purity Substances, Russian Academy of Sciences, Nizhnii Novgorod (Russian Federation)

2004-08-31T23:59:59.000Z

350

Resonant Raman scattering in an InAs/GaAs monolayer structure  

E-Print Network (OSTI)

), embedded in bulklike GaAs with two Al- GaAs cladding layers forming a waveguide. The InAs- mono- layer system used. Raman spectra were excited with a Ti-Sapphire laser, tuned from 1.41 eV to 1.435 e

Nabben, Reinhard

351

Quasitransient backward Raman amplification of powerful laser pulses in dense plasmas with multicharged ions  

E-Print Network (OSTI)

are found. The calculation, applicable to infrared, ultraviolet, soft x-ray, and x-ray laser pulses, takes technique is also applicable to shorter wavelength laser pulses including x-ray pulses for which CPA cannotQuasitransient backward Raman amplification of powerful laser pulses in dense plasmas

352

Homogeneous Decomposition Mechanisms of Diethylzinc by Raman Spectroscopy and Quantum Chemical Calculations  

E-Print Network (OSTI)

for direct reaction products in an inverted, impinging-jet test reactor coupled to a Raman spectrometer. The homogeneous thermal decomposition of DEZn in N2 carrier was followed in an impinging-jet, up-flow reactor vibrational frequencies of DEZn, as well as anticipated intermediates and products. Comparison of the measured

Anderson, Timothy J.

353

Developments in enzyme immobilization and near-infrared Raman spectroscopy with downstream renewable energy applications  

SciTech Connect

This dissertation focuses on techniques for (1) increasing ethanol yields from saccharification and fermentation of cellulose using immobilized cellulase, and (2) the characterization and classification of lignocellulosic feedstocks, and quantification of useful parameters such as the syringyl/guaiacyl (S/G) lignin monomer content using 1064 nm dispersive multichannel Raman spectroscopy and chemometrics.

Lupoi, Jason [Ames Laboratory

2012-08-27T23:59:59.000Z

354

THE RAMAN SPECTRUM OF MAGNESIUM FLUORIDE By R. S. KRISHNAN and R. S. KATIYAR,  

E-Print Network (OSTI)

627. THE RAMAN SPECTRUM OF MAGNESIUM FLUORIDE By R. S. KRISHNAN and R. S. KATIYAR, Department, NOVEMBRE 1965, I Magnesium fluoride, which occurs in nature as the mineral sellaite, crystallizes spectrum of magnesium fluoride (MgF2) taken with a medium Quartz spectrograph. (b) Its microphotometer

Paris-Sud XI, Université de

355

Spectroscopic Raman Nanometrology of Graphene and Graphene Multilayers on Arbitrary Substrates  

E-Print Network (OSTI)

Spectroscopic Raman Nanometrology of Graphene and Graphene Multilayers on Arbitrary Substrates I to be an effective tool for characterization of graphene and graphene multilayers on the standard Si/SiO2 (300 nm) substrates, which allows one to determine non-destructively the number of the graphene layers and assess

356

Effect of functionalization on the electrostatic charging, tunneling, and Raman spectroscopy of epitaxial graphene  

E-Print Network (OSTI)

of epitaxial graphene Jeongmin Hong, Sandip Niyogi, Elena Bekyarova, Mikhail E. Itkis, Palanisamy Ramesh graphene Appl. Phys. Lett. 101, 111602 (2012); 10.1063/1.4752443 Evidences of electrochemical graphene (2012); 10.1063/1.4725489 Pinned and unpinned epitaxial graphene layers on SiC studied by Raman

357

Raman spectra of out-of-plane phonons in bilayer graphene  

E-Print Network (OSTI)

The double resonance Raman spectra of the overtone of the out-of-plane tangential optical (oTO) phonon and of combinations of the LO, ZO, and ZA phonons with one another are calculated for bilayer graphene. In the case of ...

Sato, Kentaro

358

High-Sensitivity Raman Spectrometer To Study Pristine and Irradiated Interstellar Ice Analogs  

E-Print Network (OSTI)

to ionizing radiation which produces small quantities of new chemical species within the bulk of the icesHigh-Sensitivity Raman Spectrometer To Study Pristine and Irradiated Interstellar Ice Analogs Chris with low temperature ices relevant to the solar system and interstellar medium. The design is based

Kaiser, Ralf I.

359

Thermal metamorphism in the lesser Himalaya of Nepal determined from Raman spectroscopy of carbonaceous material  

E-Print Network (OSTI)

Thermal metamorphism in the lesser Himalaya of Nepal determined from Raman spectroscopy of central and far-western Nepal, including data from near the MCT zone, where a comparison with conventional on the thermal evolution of the Himalaya in Nepal using the RSCM method. This emblematic geological setting

Avouac, Jean-Philippe

360

TEMPERATURE-DEPENDENT RAMAN SPECTROSCOPY OF FULLERENE AND CARBORANE NANOCAR WHEELS  

E-Print Network (OSTI)

into a temperature difference. We can control the input voltage and current by using an external power supply to control temperature. The red and black wires are connected to the power supply. The yellow wireTEMPERATURE-DEPENDENT RAMAN SPECTROSCOPY OF FULLERENE AND CARBORANE NANOCAR WHEELS B. Shih1,2 , C

Mellor-Crummey, John

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

Raman spectroscopy of carbon dust samples from NSTX Y. Raitses a,*, C.H. Skinner a  

E-Print Network (OSTI)

.S. Duffy b a Princeton Plasma Physics Laboratory, Princeton, NJ 08543, USA b Department of Geosciences, Princeton University, NJ 08544, USA Received 13 November 2007; accepted 17 January 2008 Abstract The Raman spectrum of dust particles exposed to the NSTX plasma is different from the spectrum of unexposed particles

Duffy, Thomas S.

362

Noise suppression and enhanced focusability in plasma Raman amplifier with multi-frequency pump  

E-Print Network (OSTI)

. Fisch Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 and Department of AstrophysicalNoise suppression and enhanced focusability in plasma Raman amplifier with multi-frequency pump A Science, Princeton University, Princeton, New Jersey 08543 V. M. Malkin Department of Astrophysical

363

Low-noise detector and amplifier design for 100 ns direct detection CO{sub 2} LIDAR receiver  

SciTech Connect

The development and test results of a prototype detector/amplifier design for a background limited, pulsed 100 ns, 10--100 kHz repetition rate LIDAR/DIAL receiver system are presented. Design objectives include near-matched filter detection of received pulse amplitude and round trip time-of-flight, and the elimination of excess correlated detector/amplifier noise for optimal pulse averaging. A novel pole-zero cancellation amplifier, coupled with a state-of-the-art SBRC (Santa Barbara Research Center) infrared detector was implemented to meet design objectives. The pole-zero cancellation amplifier utilizes a tunable, pseudo-matched filter technique to match the width of the laser pulse to the shaping time of the filter for optimal SNR performance. Low frequency correlated noise, (l/f and drift noise) is rejected through a second order high gain feedback loop. The amplifier also employs an active detector bias stage minimizing detector drift. Experimental results will be provided that demonstrate near-background limited, 100 ns pulse detection performance given a 8.5--11.5 {micro}m (300 K B.B.) radiant background, with the total noise floor spectrally white for optimal pulse averaging efficiency.

Cafferty, M.M.; Cooke, B.J.; Laubscher, B.E.; Olivas, N.L.; Fuller, K.

1997-06-01T23:59:59.000Z

364

Raman spectroscopic study of the pressure-induced coordination change in GeO2 glass  

Science Journals Connector (OSTI)

Raman spectra of GeO2 glass are recorded in situ as a function of pressure to 56 GPa at room temperature. Under initial compression to 6 GPa the main 419-cm-1 Raman band shifts to higher frequency and broadens with a gradual loss of intensity. These spectral changes are consistent with an increase in distortion of GeO4 tetrahedra and a decrease in the intertetrahedral bond angle with pressure. Between 6 and 13 GPa (the pressure range of the reported fourfold- to sixfold-coordination change of Ge in germania glass) the main Raman band broadens, and the scattering intensity is dramatically reduced with little shift in peak frequency. This pressure interval is also marked with the appearance and growth of a broad low-frequency band near 240 cm-1. The inferred pressure-induced coordination change occurs without the formation of nonbridging oxygens. Above 13 GPa no further major structural changes are indicated by the Raman data taken with pressures up to 56 GPa. On decompression the back transformation of octahedral Ge to tetrahedral coordination is complete but exhibits a large hysteresis. The Raman data indicate that the high-coordinate germanium species are retained down to pressures of at least 2.3 GPa. In samples decompressed from high pressures, the intensity of the 520-cm-1 ‘‘defect’’ band is considerably enhanced relative to that in normal germania glass, consistent with an increase in three-membered-ring population. It is proposed that a large component of this increase in three-membered rings is a result of the reversion of OIII species to tetrahedra-bridging OII species under decompression.

Dan J. Durben and George H. Wolf

1991-01-15T23:59:59.000Z

365

ARM - Facility News Article  

NLE Websites -- All DOE Office Websites (Extended Search)

October 6, 2010 [Facility News] October 6, 2010 [Facility News] New Raman Lidar En Route to Australia Bookmark and Share Since 1996, the ARM Southern Great Plains site has maintained one of the few operational Raman lidars in the world. Now, thanks to funding from the American Recovery and Reinvestment Act, the ARM Tropical Western Pacific site is about to join that exclusive group. A new Raman lidar, built by Sandia National Laboratories in New Mexico, is on its way to Darwin, Australia. Optics contained inside the Raman lidar shelter guide backscattered laser radiation in order to measure signals collected by the telescope. Optics contained inside the Raman lidar shelter guide backscattered laser radiation in order to measure signals collected by the telescope. The Raman lidar (light detection and ranging) uses pulses of laser

366

Multiwavelength Raman spectroscopy analysis of a large sampling of disordered carbons extracted from the Tore Supra tokamak  

E-Print Network (OSTI)

Disordered carbon often exhibit a complex Raman spectrum, with four to six components. Here, a large variety of disordered carbons, forming a collection of samples with a great variety of structures, are analysed using multi-wavelength Raman microscopy (325.0, 514.5, 785.0 nm). They allow us to extend Raman behaviour known for nano-crystalline graphite to amorphous carbons, (dependence with the excitation wavelength) and other known for amorphous carbons to nano-crystalline graphite, (differentiation of the smallest cluster size probed using different excitation wavelengths). Experimental spectra were compared to simulated spectra, built using known laws, to evidence a new source of broadening.

Pardanaud, Cedric; Roubin, P

2014-01-01T23:59:59.000Z

367

Detection of internally mixed Asian dust with air pollution aerosols using a polarization optical particle counter and a polarization-sensitive two-wavelength lidar  

Science Journals Connector (OSTI)

Abstract East Asia is a unique region where mineral dust (Asian dust) sources are located near urban and industrial areas. Asian dust is often mixed with air pollution aerosols during transportation. It is important to understand the mixing states of Asian dust and other aerosols, because the effects on the environment and human health differ depending on the mixing state. We studied the mixing states of Asian dust using a polarization particle counter (POPC) that measures the forward scattering and the two polarization components of backscattering for single particles and a polarization-sensitive (532 nm) two-wavelength (1064 nm and 532 nm) lidar. We conducted the simultaneous observations using the POPC and the lidar in Seoul from March to December 2013 and captured the characteristics of pure Asian dust and internally mixed polluted Asian dust. POPC measurements indicated that the density of large particles was lower in polluted Asian dust that transported slowly over the polluted areas than in pure Asian dust that transported quickly from the dust source region. Moreover, the backscattering depolarization ratio was smaller for all particle sizes in polluted dust. The optical characteristics measured using the lidar were consistent with the POPC measurements. The backscattering color ratio of polluted dust was comparable to that of pure dust, but the depolarization ratio was lower for polluted dust. In addition, coarse non-spherical particles (Asian dust) almost always existed in the background, and the depolarization ratio had seasonal variation with a lower depolarization ratio in the summer. These results suggest background Asian dust particles are internally mixed in the summer.

Nobuo Sugimoto; Tomoaki Nishizawa; Atsushi Shimizu; Ichiro Matsui; Hiroshi Kobayashi

2015-01-01T23:59:59.000Z

368

Reevaluation of Type I Diamonds for Infrared and Raman Spectroscopy in High-Pressure Diamond Anvil Cells  

Science Journals Connector (OSTI)

Types Ia, IIa, and IIb diamonds have been compared for their use as anvils in infrared and Raman high-pressure spectroscopy. In the mid-infrared region above 2700 cm?1,...

Wong, P T T; Klug, D D

1983-01-01T23:59:59.000Z

369

Effect of the finishing oil of acrylic fibers in the optical rotation of the Raman scattered light  

Science Journals Connector (OSTI)

Polarized Raman spectra have been obtained from polyacrylonitrile copolymers fibers with vinyl acetate Poly(AN-co-VA), and methyl acrylate Poly(AN-co-MA) with finishing and without...

Rosales-Candelas, I; Soto-Bernal, J J; Gonzalez-Mota, R; Frausto-Reyes, C

2013-01-01T23:59:59.000Z

370

Assessment of liver steatosis and fibrosis in rats using integrated coherent anti-Stokes Raman scattering and multiphoton imaging technique  

E-Print Network (OSTI)

We report the implementation of a unique integrated coherent anti-Stokes Raman scattering (CARS), second-harmonic generation (SHG), and two-photon excitation fluorescence (TPEF) microscopy imaging technique developed for ...

Lin, Jian

371

Wildfire hazard in the home ignition zone: An object-oriented analysis integrating LiDAR and VHR satellite imagery  

Science Journals Connector (OSTI)

Abstract Many spatially explicit studies of wildfire hazard focus on the wildland–urban interface (WUI), the area where natural vegetation intersects or mixes with structures. However, research suggests that the characteristics of a small portion of the WUI, the home ignition zone, largely determine potential for ignition from wildfire. The home ignition zone (HIZ) is the area that includes a structure and its surroundings out to 30–60 m. The primary goal of this study is to develop metrics to characterize land cover, burned area, and topography in the HIZ. Pre-fire metrics (i.e. related to land cover and topography) help identify relatively hazardous individual \\{HIZes\\} or neighborhoods of HIZes. Post-fire metrics can be used to assess the burned area across land cover types, inside and outside the HIZ. To calculate the HIZ metrics, multiple data sources (e.g. high resolution 8-band multispectral imagery and LiDAR point clouds) were integrated using an object-oriented image analysis. The setting for the study is the Fourmile Canyon area west of Boulder, Colorado, a data-rich area which experienced a large, destructive wildfire in September 2010. The land cover, burn area, and topography metrics were successfully and accurately calculated and then pre-fire metrics were combined into a simple HIZ hazard index. HIZ characteristics broadly mirror the characteristics of the WUI within the fire perimeter as a whole, though the HIZ on average contains more bare and less forest land, has more widely spaced canopies, and experienced less burning during the fire. The HIZ hazard index values were spatially heterogeneous, but with several distinct high and low hazard clusters. The methods described in this study, paired with in situ data collection, can be applied to other areas to inform hazard mitigation plans.

Rutherford V. Platt

2014-01-01T23:59:59.000Z

372

Impact of Vaisala Radiosonde Humidity Corrections on ARM IOP...  

NLE Websites -- All DOE Office Websites (Extended Search)

dry bias in Vaisala radiosonde humidity measurements has been noted in comparison to satellite water vapor retrievals (Soden and Lanzante 1996) and Raman lidar measurements...

373

Four-Dimensional Data Assimilation X. Hong, M. J. Leach, and S. Raman  

NLE Websites -- All DOE Office Websites (Extended Search)

X. Hong, M. J. Leach, and S. Raman X. Hong, M. J. Leach, and S. Raman Department of Marine, Earth and Atmospheric Sciences .North Carolina State University Raleigh, NC 27695-8208 Surface inhomogeneities, including boundaries between different types of vegetations and land use patterns, have important effects on the structure of the atmospheric boundary layer. Changes in the surface roughness, temperature and wetness make the planetary boundary layer (PBL) nonhomogeneous and produce substantial horizontal gradients of boundary layer properties. Significant differences in the surface thermal energy induce mesoscale circulations. The presence of vegetation modulates the evaporation from the soil and enhances the vertical flux of water vapor into the PBL through transpiration. A realistic canopy

374

Characterization of Gas Shales by X-ray Raman Spectroscopy | Stanford  

NLE Websites -- All DOE Office Websites (Extended Search)

Characterization of Gas Shales by X-ray Raman Spectroscopy 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 Unconventional hydrocarbon resources such as gas shale and oil-bearing shale have emerged recently as economically viable sources of energy, dramatically altering America's energy landscape. Despite their importance, the basic chemistry and physics of shales are not understood as well as conventional reservoirs. In particular, shales are unique in that they contain kerogen, a complex organic solid that controls factors such as the amount of hydrocarbon that can be produced from the reservoir and the rate at which the hydrocarbon is produced. The industry's current understanding of the chemical composition of kerogen is limited, preventing detailed

375

Gulf Stream Locale R. J. Alliss and S. Raman Department of Marine, Earth and Atmospheric Sciences  

NLE Websites -- All DOE Office Websites (Extended Search)

R. J. Alliss and S. Raman R. J. Alliss and S. Raman Department of Marine, Earth and Atmospheric Sciences North Carolina State University Raleigh, NC 27695-8208 Introduction Clouds have long been recognized as having a major impact on the radiation budget in the earth's climate system. One of the preferred areas for the production of clouds is off the east coast of the United States. The formation of clouds in this region, particularly during the winter months, is caused predominately by the presence of the Gulf Stream, which flows northeastward just off the southeast coast. The geography of the region is such that the cold North American continent lies adjacent to the relatively warm shelf waters (1 DOC), which in turn are bounded by the much warmer Gulf Stream (25°C). The Sargasso Sea to the east of the Gulf Stream consists of

376

Characterization of Gas Shales by X-ray Raman Spectroscopy | Stanford  

NLE Websites -- All DOE Office Websites (Extended Search)

Characterization of Gas Shales by X-ray Raman Spectroscopy 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 resources such as gas shale and oil-bearing shale have emerged recently as economically viable sources of energy, dramatically altering America's energy landscape. Despite their importance, the basic chemistry and physics of shales are not understood as well as conventional reservoirs. In particular, shales are unique in that they contain kerogen, a complex organic solid that controls factors such as the amount of hydrocarbon that can be produced from the reservoir and the rate at which the hydrocarbon is produced. The industry's current understanding of the chemical composition of kerogen is limited, preventing detailed

377

Stimulated Raman Scattering and Nonlinear Focusing of High-Power Laser Beams Propagating in Water  

E-Print Network (OSTI)

The physical processes associated with propagation of a high-power (power > critical power for self-focusing) laser beam in water include nonlinear focusing, stimulated Raman scattering (SRS), optical breakdown and plasma formation. The interplay between nonlinear focusing and SRS is analyzed for cases where a significant portion of the pump power is channeled into the Stokes wave. Propagation simulations and an analytical model demonstrate that the Stokes wave can re-focus the pump wave after the power in the latter falls below the critical power. It is shown that this novel focusing mechanism is distinct from cross-phase focusing. While discussed here in the context of propagation in water, the gain-focusing phenomenon is general to any medium supporting nonlinear focusing and stimulated forward Raman scattering.

Hafizi, B; Penano, J R; Gordon, D F; Jones, T G; Helle, M H; Kaganovich, D

2015-01-01T23:59:59.000Z

378

Studies of ground-state dynamics in isolated species by ionization-detected stimulated Raman techniques  

SciTech Connect

First, the author aims to develop methods of nonlinear Raman spectroscopy for application in studies of sparse samples. Second, the author wishes to apply such methods to structural and dynamical studies of species (molecules, complexes, and clusters) in supersonic molecular beams. In the past year, the author has made progress in several areas. The first pertains to the application of mass-selective ionization-detected stimulated Raman spectroscopies (IDSRS) to the size-specific vibrational spectroscopy of solute-solvent{sub n} clusters. The second involves the application of IDSRS methods to studies of jet-cooled benzene clusters. The third pertains to the use of IDSRS methods in the study of intermolecular vibrational transitions in van der Waals complexes.

Felker, P.M. [Univ. of California, Los Angeles (United States)

1993-12-01T23:59:59.000Z

379

Single-pulse Raman scattering study of triaminotrinitrobenzene under shock compression  

SciTech Connect

Pulsed-laser-excited Raman scattering methods have been used to examine the dynamic molecular-level response of an explosive molecule (triaminotrinitrobenzene, TATB) to sustained shock loading at a fused silica window interface. The anomalous behavior of Raman modes associated with nitro groups in the molecule (the 881-cm/sup /minus/1/ NO/sub 2/ deformation mode, the 1146 cm/sup /minus/1/ symmetric C-NO/sub s/ stretching mode, and the 1170-cm/sup /minus/1/ totally symmetric NO/sub 2/ stretching mode) is compared to results obtained under static high pressure. The shock compression data indicate that elevated temperatures act to restrain pressure-enhanced coupling of NO/sub 2/ and NH/sub 2/ groups in the molecule. Differences in the spectra obtained under static and dynamic high-pressure conditions are discussed in relation to the known insensitivity of TATB to shock initiation.

Trott, W.M.; Renlund, A.M.

1988-10-20T23:59:59.000Z

380

Raman spectroscopic studies of shock-compressed nitromethane and nitromethane-d/sub 3/  

SciTech Connect

Single-pulse Raman spectroscopy has been used to examine the effect of shock compression on the C-N stretching modes near 900 cm/sup /minus/1/ in a 50/50 mixture of nitromethane (NM) and perdeutero nitromethane (NM-d/sub 3/). Samples were shocked in a single step to pressures as high as 6.8 GPa using a compressed gas gun driver. Spectra up to 5.5 GPa showed he expected pressure-induced shifting of the Raman frequencies; at higher pressures the lines were significantly broadened and the frequency shift was reversed, indicating the initial stages of reaction. In no instance did we see significant isotopic exchange as would be evidenced by alteration of the relative line intensities. 6 refs., 3 figs., 1 tab.

Renlund, A.M.; Trott, W.M.

1989-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

UV-Photoreflectance and Raman Characterization of Strain Relaxation in Si on Silicon-Germanium Films  

SciTech Connect

Photoreflectance (PR), using a uv (374 nm) diode laser probe beam, and Raman spectroscopy, using a multi-wavelength Ar{sup +} laser coupled to a high-resolution multi-wavelength spectrometer, were used to characterize the strain relaxation of Si top layers grown on a graded and relaxed SiGe buffer stack with a final Ge concentration of 20%. The Si top layer thicknesses ranged from 1.6 to 18 nm. Considerable radial variation in the strain relaxation was seen in all sampled wafers, highlighting the need for rapid, local strain characterization. Strong correlation between shift in the Si layer dielectric response, measured by uv-PR, and the Si top layer strain, measured by Raman, is reported.

Current, Michael [Current Scientific, 1729 Comstock Way, San Jose, CA 95124 (United States); Chism, Will [Xitronix Corporation, 106 East Sixth Street, Ninth Floor, Austin TX, 78701 (United States); Yoo, Woo Sik [WaferMasters, Inc., 246 East Gist Road, San Jose, CA 95112 (United States); Vartanian, Victor [International Sematech Manufacturing Initiative, 257 Fuller Road, Suite 2200, Albany NY 12203 (United States)

2011-11-10T23:59:59.000Z

382

Secondary ion mass spectrometry and Raman spectroscopy for tissue engineering applications  

Science Journals Connector (OSTI)

Identifying the matrix properties that permit directing stem cell fate is crucial for expanding desired cell lineages ex vivo for disease treatment. Such efforts require knowledge of matrix surface chemistry and the cell responses they elicit. Recent progress in analyzing biomaterial composition and identifying cell phenotype with two label-free chemical imaging techniques, TOF-SIMS and Raman spectroscopy are presented. TOF-SIMS is becoming indispensable for the surface characterization of biomaterial scaffolds. Developments in TOF-SIMS data analysis enable correlating surface chemistry with biological response. Advances in the interpretation of Raman spectra permit identifying the fate decisions of individual, living cells with location specificity. Here we highlight this progress and discuss further improvements that would facilitate efforts to develop artificial scaffolds for tissue regeneration.

Yelena Ilin; Mary L Kraft

2015-01-01T23:59:59.000Z

383

Time interval and lattice vibration in Raman effect, photoelectric effect and plane mirror reflection  

E-Print Network (OSTI)

Time interval between the incident and scattered photon in Raman effect and absorption of photon and emission of electron in photoelectric effect has not been determined till now. This is because there is no such high level instrument discovered till now to detect time interval to such a small level. But this can be calculated theoretically by applying a basic principle of physics like impulse is equal to the change in momentum. Considering the collision between electron and photon as perfect inelastic collision in photoelectric effect, elastic and inelastic collision in Raman effect and elastic collision in plane mirror reflection and the interaction between electron and photon as strong gravitational interaction we calculate the required time interval. During these phenomena there is lattice vibration which can be quantized as phonon particles.

M. Kumar; S. Sahoo

2012-07-02T23:59:59.000Z

384

Probing the pairing symmetry of the iron pnictides with electronic Raman scattering  

SciTech Connect

An important issue in the study of the iron-arsenic based superconductors is the symmetry of the superconducting gap, a problem complicated by multiple gaps on different Fermi surface sheets. Electronic Raman scattering is a flexible bulk probe which allows one in principle to determine gap magnitudes and test for gap nodes in different regions of the Brillouin zone by employing different photon polarization states. Here we calculate the clean Raman intensity for A{sub 1g}, B{sub 1g} and B{sub 2g} polarizations, and discuss the peak structures and low-energy power laws which might be expected for several popular models of the superconducting gap in these systems.

Boyd, G.R.

2010-04-29T23:59:59.000Z

385

Femtosecond Raman induced polarization spectroscopy studies of coherent rotational dynamics in molecular fluids  

SciTech Connect

We develop a polarization-sensitive femtosecond pump probe technique, Raman induced polarization spectroscopy (RIPS), to study coherent rotation in molecular fluids. By observing the collisional dephasing of the coherently prepared rotational states, we are able to extract information concerning the effects of molecular interactions on the rotational motion. The technique is quite sensitive because of the zero background detection method, and is also versatile due to its nonresonant nature.

Morgen, M.M. [Univ. of California, Berkeley, CA (United States). Dept. of Chemistry; [Lawrence Berkeley National Lab., CA (United States)

1997-05-01T23:59:59.000Z

386

All-Optical Blister Test of Suspended Graphene Using Micro-Raman Spectroscopy  

Science Journals Connector (OSTI)

We report a comprehensive micro-Raman study of a pressurized suspended graphene membrane that hermetically seals a circular pit, etched in a Si/SiO2 substrate. Placing the sample under a uniform pressure load results in bulging of the graphene membrane and subsequent softening of the main Raman features, due to tensile strain. In such a microcavity, the intensity of the Raman features depends very sensitively on the distance between the graphene membrane and the Si substrate, which acts as the bottom mirror of the cavity. Thus, a spatially resolved analysis of the intensity of the G- and 2D-mode features as a function of the pressure load permits a direct reconstruction of the blister profile. An average strain is then deduced at each pressure load, and Grüneisen parameters of 1.8±0.2 and 2.4±0.2 are determined for the Raman G and 2D modes, respectively. In addition, the measured blister height is proportional to the cubic root of the pressure load, as predicted theoretically. The validation of this scaling provides a direct and accurate determination of the Young’s modulus of graphene with a purely optical, hence contactless and minimally invasive, approach. We find a Young’s modulus of (1.05±0.10)??TPa for monolayer graphene, in a perfect match with previous nanoindentation measurements. This all-optical methodology opens avenues for pressure sensing using graphene and could readily be adapted to other emerging two-dimensional materials and to nanoresonators.

Dominik Metten; François Federspiel; Michelangelo Romeo; Stéphane Berciaud

2014-11-11T23:59:59.000Z

387

Low-frequency Raman spectra and fragility of imidazolium ionic liquids  

SciTech Connect

Raman spectra within the 5-200 cm{sup -1} range have been recorded as a function of temperature for different ionic liquids based on imidazolium cations. A correlation has been found between fragility and the temperature dependence of the strength of fast relaxational motions. Understanding quasielastic scattering as the relaxational contribution to ionic mean-squared displacement elucidates some effects on ionic liquids' fragility resulting from modifications in the chemical structure.

Ribeiro, Mauro C. C. [Laboratorio de Espectroscopia Molecular, Instituto de Quimica, Universidade de Sao Paulo, CP 26077, CEP 05513-970 Sao Paulo, Sao Paulo (Brazil)

2010-07-14T23:59:59.000Z

388

Low-frequency Raman spectra and fragility of imidazolium ionic liquids  

Science Journals Connector (OSTI)

Raman spectra within the 5 – 200 ? cm ? 1 range have been recorded as a function of temperature for different ionic liquids based on imidazolium cations. A correlation has been found between fragility and the temperature dependence of the strength of fast relaxational motions. Understanding quasielastic scattering as the relaxational contribution to ionic mean-squared displacement elucidates some effects on ionic liquids’ fragility resulting from modifications in the chemical structure.

Mauro C. C. Ribeiro

2010-01-01T23:59:59.000Z

389

UV-Raman spectroscopy on nanotubes@zeolite Wavelength dependence Ab initio calculations  

E-Print Network (OSTI)

UV-Raman spectroscopy on nanotubes@zeolite June, 2005 Wavelength dependence Ab initio calculations 4 Energy (eV) 0 2 4 Energy (eV) (arb.units) (2,1) (4,1) (5,0) (3,3) (4,2)(4,0) (2,2) (3,0) 1Institut involving the peak at 650 cm-1. Nanotubes grown inside the channels of zeolite crystals are constrained

Nabben, Reinhard

390

Rotational and Vibrational Raman Spectroscopy for Thermochemistry Measurements in Supersonic Flames  

E-Print Network (OSTI)

) is collected with laser excitation. (c) The recorded chemiluminescence is directly subtracted from the ame?s total signal. The data shown here is for ame location z = 4 mm & r = 0 mm, and is averaged over 100 shots.... In what will follow, we highlight and discuss the major techniques and contributions to the eld. Raman measurements in supersonic hydrogen-air di usion ames by R. Pitz and his group at Vanderbilt [18] provide one of the earliest applications...

Bayeh, Alexander C

2013-05-31T23:59:59.000Z

391

Raman spectroscopy of some complex arsenate minerals—implications for soil remediation  

Science Journals Connector (OSTI)

The application of spectroscopy to the study of contaminants in soils is important. Among the many contaminants is arsenic, which is highly labile and may leach to non-contaminated areas. Minerals of arsenate may form depending upon the availability of specific cations for example calcium and iron. Such minerals include carminite, pharmacosiderite and talmessite. Each of these arsenate minerals can be identified by its characteristic Raman spectrum enabling identification.

Ray L. Frost; J.Theo Kloprogge

2003-01-01T23:59:59.000Z

392

Stimulated Raman back scattering of extraordinary electromagnetic waves from periodically magnetized nanoparticle lattice  

SciTech Connect

Stimulated Raman back scattering of extraordinary electromagnetic waves from the nanoparticle lattice is investigated in the presence of the static magnetic field. In the context of macroscopic theory, dispersion relation and growth rate of extraordinary mode for different values of static magnetic field and lattice parameters are derived and analyzed. It is found that when the static magnetic field is off, dispersion relation has two branches. These branches are related to the plasmonic and body wave branches of the plane polarized wave. Low frequency branch of the pump wave is not involved in the instability while the other branch is not stable, and the growth rate of Raman back scattered wave has one peak. If the electrons have cyclotron frequency by static magnetic field, dispersion has three branches. These branches are related to the plasmonic and body wave branches of left and right hand circularly polarized waves. In this situation, it is found that low frequency lower branch of the pump wave is stable while other branches are not stable, and the growth rate of Raman back scattered wave has three peaks. Numerical study of growth rate in various cyclotron frequencies shows that the growth rate increases and the instability band width decreases with increasing static magnetic field.

Chakhmachi, A. [Plasma Physics and Nuclear Fusion Research School, Nuclear Science and Technology Research Institute, P.O. Box 14155-1339, Tehran (Iran, Islamic Republic of)] [Plasma Physics and Nuclear Fusion Research School, Nuclear Science and Technology Research Institute, P.O. Box 14155-1339, Tehran (Iran, Islamic Republic of)

2013-06-15T23:59:59.000Z

393

Raman-dressed spin-1 spin-orbit-coupled quantum gas  

Science Journals Connector (OSTI)

The recently realized spin-orbit-coupled quantum gases [Lin et al., Nature (London) 471, 83 (2011); Wang et al., Phys. Rev. Lett. 109, 095301 (2012); Cheuk et al., Phys. Rev. Lett. 109, 095302 (2012)] mark a breakthrough in the cold atom community. In these experiments, two hyperfine states are selected from a hyperfine manifold to mimic a pseudospin-1/2 spin-orbit-coupled system by the method of Raman dressing, which is applicable to both bosonic and fermionic gases. In this paper, we show that the method used in these experiments can be generalized to create any large pseudospin spin-orbit-coupled gas if more hyperfine states are coupled equally by the Raman lasers. As an example, we study, in detail, a quantum gas with three hyperfine states coupled by the Raman lasers and show, when the state-dependent energy shifts of the three states are comparable, triple-degenerate minima will appear at the bottom of the band dispersions, thus, realizing a spin-1 spin-orbit-coupled quantum gas. A novel feature of this three-minima regime is that there can be two different kinds of stripe phases with different wavelengths, which has an interesting connection to the ferromagnetic and polar phases of spin-1 spinor Bose-Einstein condensates without spin-orbit coupling.

Zhihao Lan and Patrik Öhberg

2014-02-24T23:59:59.000Z

394

CuAl{sub 2} revisited: Composition, crystal structure, chemical bonding, compressibility and Raman spectroscopy  

SciTech Connect

The structure of CuAl{sub 2} is usually described as a framework of base condensed tetragonal antiprisms [CuAl{sub 8/4}]. The appropriate symmetry governed periodic nodal surface (PNS) divides the space of the structure into two labyrinths. All atoms are located in one labyrinth, whereas the second labyrinth seems to be 'empty'. The bonding of the CuAl{sub 2} structure was analyzed by the electron localization function (ELF), crystal orbital Hamiltonian population (COHP) analysis and Raman spectroscopy. From the ELF representation it is seen, that the 'empty' labyrinth is in fact the place of important covalent interactions. ELF, COHP in combination with high-pressure X-ray diffraction and Raman spectroscopy show that the CuAl{sub 2} structure is described best as a network built of interpenetrating graphite-like nets of three-bonded aluminum atoms with the copper atoms inside the tetragonal-antiprismatic cavities. - Graphical abstract: Atomic interactions in the crystal structure of the intermetallic compound CuAl{sub 2}: Three-bonded aluminum atoms form interpenetrating graphite-like nets. The copper atoms are located in the channels of aluminum network by means of three-center bonds. The bonding model is in agreement with the result of polarized Raman spectroscopy and high-pressure X-ray powder diffraction.

Grin, Yuri [Max-Planck-Institut fuer Chemische Physik fester Stoffe, Noethnitzer Strasse 40, 01187 Dresden (Germany)]. E-mail: grin@cpfs.mpg.de; Wagner, Frank R. [Max-Planck-Institut fuer Chemische Physik fester Stoffe, Noethnitzer Strasse 40, 01187 Dresden (Germany); Armbruester, Marc [Max-Planck-Institut fuer Chemische Physik fester Stoffe, Noethnitzer Strasse 40, 01187 Dresden (Germany); Kohout, Miroslav [Max-Planck-Institut fuer Chemische Physik fester Stoffe, Noethnitzer Strasse 40, 01187 Dresden (Germany); Leithe-Jasper, Andreas [Max-Planck-Institut fuer Chemische Physik fester Stoffe, Noethnitzer Strasse 40, 01187 Dresden (Germany); Schwarz, Ulrich [Max-Planck-Institut fuer Chemische Physik fester Stoffe, Noethnitzer Strasse 40, 01187 Dresden (Germany); Wedig, Ulrich [Max-Planck-Institut fuer Festkoerperforschung, Heisenbergstr. 1, 70569 Stuttgart (Germany); Georg von Schnering, Hans [Max-Planck-Institut fuer Festkoerperforschung, Heisenbergstr. 1, 70569 Stuttgart (Germany)

2006-06-15T23:59:59.000Z

395

Raman scattering investigation of a Ge/SiO2/Si nanocrystal system under hydrostatic pressure  

Science Journals Connector (OSTI)

We have studied the hydrostatic pressure dependence of Ge nanocrystals embedded in a SiO2 matrix on a Si substrate by Raman scattering at room temperature. During the first cycle of increasing pressure, we observed a step change in the Ge Raman mode from 310.4 to 313.8 cm-1 at ?23 kbar. The linear pressure coefficients ? obtained before and after the step change at ?23 kbar are 0.42 and 0.64 cm-1 kbar-1, respectively. Upon decreasing pressure, the Ge mode follows a single slope of pressure coefficient ?=0.64 cm-1 kbar-1. A finite-element analysis was carried out to investigate the elastic-field distribution in the Ge/SiO2/Si nanocrystal system, where the discontinuity of the specific geometric configuration with different elastic constants causes local areas of stress concentration around the interface. The step change of the Raman shifts with pressure at ?23 kbar was attributed to complete delamination between the SiO2 film and the Si substrate.

Lei Liu; K. L. Teo; Z. X. Shen; J. S. Sun; E. H. Ong; A. V. Kolobov; Y. Maeda

2004-03-23T23:59:59.000Z

396

Raman Spectroscopic and Ultrasonic Measurements to Monitor the HMX ( ) Phase Transition  

SciTech Connect

The HMX {beta}-{delta} solid-solid phase transition, which occurs as HMX is heated near 170 C, is clearly linked to increased reactivity and sensitivity to initiation. Thermally damaged energetic materials (EMs) containing HMX therefore may present a safety concern. Information about the phase transition is vital to a predictive safety model for HMX and HMX-containing EMs. We report work in progress on monitoring the phase transition with real-time Raman spectroscopy and ultrasonic measurements aimed towards a better understanding of physical properties through the phase transition. HMX samples were confined with minimal free volume.in a cell with constant volume. The cell was heated at a controlled rate and real-time Raman spectroscopic or ultrasonic measurements were performed. Raman spectroscopy provides a clear distinction between the two phases because the vibrational transitions of the molecule change with confirmational changes associated with the phase transition. Ultrasonic time-of-flight measurements provide an additional method of distinguishing the two phases because the sound speed through the material changes with the phase transition. Ultrasonic attenuation measurements also provide information about microstructural changes such as increased porosity due to evolution of gaseous decomposition products.

GIESKE,JOHN H.; MILLER,JILL C.; RENLUND,ANITA M.; TAPPAN,ALEXANDER S.

1999-10-14T23:59:59.000Z

397

Stimulated Raman scattering from free holes in p-type indium antimonide  

Science Journals Connector (OSTI)

Stimulated Raman scattering from photoexcited holes at magnetic fields up to 68 kG in p-InSb is described. Experiments varying excitation wavelength, magnetic field, polarization, and sample orientation are discussed. A comparison of the experimental results with the latest valence-band calculations allows the identification of the energy levels involved in the scattering process. For sample orientation H???100?, the initial state is the valence-band Landau level ALH 101+31 and the final state is BHH 313-31. ALH, BLH are the "light hole" ladders (approximate spin M=+32 and M=-32, respectively). AHH, BHH are the "heavy hole" ladders (approximate spin M=-12 and M=+12, respectively). For the orientation H???111? initial state and final state are BLH 000+ and AHH 32O+, respectively. The holes involved in this Raman scattering process always have a nonzero momentum along the direction of the magnetic field (kH?0). The largest Raman shift we measured was about 2.7 cm-1.

R. Ebert, H. Pascher, and H. G. Häfele

1981-06-15T23:59:59.000Z

398

The Origin of Surface-Enhanced Raman Scattering of 4,4' -Biphenyldicarboxylate on Silver Substrates  

SciTech Connect

We combine scanning electron microscopy, atomic force microscopy, surface-enhanced Raman scattering (SERS), and tools of computational chemistry to investigate the origin of Raman scattering of 4,4’-biphenyldicarboxylic acid adsorbed as 4,4’-biphenyldicarboxylate on two different silver substrates. The first consists of a 100 nm deep cylindrical aperture embedded in an array of cylindrical nano-holes featuring an average diameter of 350 nm and a periodicity of 700 nm. The second is a nano-junction formed by a 100 nm silver nano-particle coated with the adsorbate and a flat silver surface. We find that the underlying background signal in the SERS spectra collected from the former strongly resemble the SERS spectra of the nano-sphere-featuring substrate, engineered to operate in the charge transfer plasmon limit. Our analysis of a series of SERS spectra consecutively collected from one nano-cylinder suggests that the optical response of a single molecule can be extracted, its brightest Raman active mode enhanced by a factor of 7.4 x 106.

El-Khoury, Patrick Z.; Peppernick, Samuel J.; Hu, Dehong; Joly, Alan G.; Hess, Wayne P.

2013-04-11T23:59:59.000Z

399

Raman and infrared spectroscopy of arsenates of the roselite and fairfieldite mineral subgroups  

Science Journals Connector (OSTI)

Raman spectroscopy complimented with infrared spectroscopy has been used to determine the molecular structure of the roselite arsenate minerals of the roselite and fairfieldite subgroups of formula Ca2B(AsO4)2·2H2O (where B may be Co, Fe2+, Mg, Mn, Ni and Zn). The Raman arsenate (AsO4)2? stretching region shows strong differences between the roselite arsenate minerals which is attributed to the cation substitution for calcium in the structure. In the infrared spectra complexity exists with multiple (AsO4)2? antisymmetric stretching vibrations observed, indicating a reduction of the tetrahedral symmetry. This loss of degeneracy is also reflected in the bending modes. Strong Raman bands around 450 cm?1 are assigned to ?4 bending modes. Multiple bands in the 300–350 cm?1 region assigned to ?2 bending modes provide evidence of symmetry reduction of the arsenate anion. Three broad bands for roselite are found at 3450, 3208 and 3042 cm?1 and are assigned to OH stretching bands. By using a Libowitzky empirical equation hydrogen bond distances of 2.75 and 2.67 Å are estimated. Vibrational spectra enable the molecular structure of the roselite minerals to be determined and whilst similarities exist in the spectral patterns, sufficient differences exist to be able to determine the identification of the minerals.

Ray L. Frost

2009-01-01T23:59:59.000Z

400

Ultrasensitive and Quantitative Detection of a New ?-Agonist Phenylethanolamine A by a Novel Immunochromatographic Assay Based on Surface-Enhanced Raman Scattering (SERS)  

Science Journals Connector (OSTI)

After ICA procedures, the specific Raman scattering intensity of MBA on the test line was measured for quantitative detection of PA. ... (21-24) However, although the conventional qualitative analysis can meet the needs of detection of some analytes (e.g., pregnancy testing), it is not suitable in some cases when the quantitative level of an analyte is important. ... The Raman intensity of the AuMBA@Ag solutions was tested by the portable Raman Analyzer. ...

Mingxin Li; Hong Yang; Shuqun Li; Kang Zhao; Jianguo Li; Danni Jiang; Lulu Sun; Anping Deng

2014-10-24T23:59:59.000Z

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Simultaneous Cancellation of Fiber Loss, Dispersion, and Kerr Effect in Ultralong-Haul Optical Fiber Transmission by Midway Optical Phase Conjugation Incorporated With Distributed Raman Amplification  

Science Journals Connector (OSTI)

An alternative application of distributed Raman amplification (DRA) for ultralong-haul optical fiber transmission is proposed. In our study, the DRA is employed in a transmission...

Kaewplung, Pasu; Kikuchi, Kazuro

2007-01-01T23:59:59.000Z

402

Detection of surface carbon and hydrocarbons in hot spot regions of niobium superconducting rf cavities by Raman spectroscopy  

Raman microscopy/spectroscopy measurements are presented on high purity niobium (Nb) samples, including pieces from hot spot regions of a tested superconducting rf cavity that exhibit a high density of etch pits. Measured spectra are compared with density functional theory calculations of Raman-active, vibrational modes of possible surface Nb-O and Nb-H complexes. The Raman spectra inside particularly rough pits in all Nb samples show clear differences from surrounding areas, exhibiting enhanced intensity and sharp peaks. While some of the sharp peaks are consistent with calculated NbH and NbH2 modes, there is better overall agreement with C-H modes in chain-type hydrocarbons. Other spectra reveal two broader peaks attributed to amorphous carbon. Niobium foils annealed to >2000°C in high vacuum develop identical Raman peaks when subjected to cold working. Regions with enhanced C and O have also been found by SEM/EDX spectroscopy in the hot spot samples and cold-worked foils, corroborating the Raman results. Such regions with high concentrations of impurities are expected to suppress the local superconductivity and this may explain the correlation between hot spots in superconducting rf (SRF) cavities and the observation of a high density of surface pits. The origin of localized high carbon and hydrocarbon regions is unclear at present but it is suggested that particular processing steps in SRF cavity fabrication may be responsible.

Cao, C.; Ford, D.; Bishnoi, S.; Proslier, T.; Albee, B.; Hommerding, E.; Korczakowski, A.; Cooley, L.; Ciovati, G.; Zasadzinski, J. F.

2013-06-01T23:59:59.000Z

403

LDRD final report : raman spectroscopic measurements to monitor the HMX beta-delta phase transition.  

SciTech Connect

The HMX {beta}-{delta} solid-solid phase transition, which occurs as HMX is heated near 170 C, is linked to increased reactivity and sensitivity to initiation. Thermally damaged energetic materials (EMs) containing HMX therefore may present a safety concern. Information about the phase transition is vital to predictive safety models for HMX and HMX-containing EMs. We report work on monitoring the phase transition with real-time Raman spectroscopy aimed towards obtaining a better understanding of physical properties of HMX through the phase transition. HMX samples were confined in a cell of minimal free volume in a displacement-controlled or load-controlled arrangement. The cell was heated and then cooled at controlled rates while real-time Raman spectroscopic measurements were performed. Raman spectroscopy provides a clear distinction between the phases of HMX because the vibrational transitions of the molecule change with conformational changes associated with the phase transition. Temperature of phase transition versus load data are presented for both the heating and cooling cycles in the load-controlled apparatus, and general trends are discussed. A weak dependence of the temperature of phase transition on load was discovered during the heating cycle, with higher loads causing the phase transition to occur at a higher temperature. This was especially true in the temperature of completion of phase transition data as opposed to the temperature of onset of phase transition data. A stronger dependence on load was observed in the cooling cycle, with higher loads causing the reverse phase transitions to occur at a higher cooling temperature. Also, higher loads tended to cause the phase transition to occur over a longer period of time in the heating cycle and over a shorter period of time in the cooling cycle. All three of the pure HMX phases ({alpha}, {beta} and {delta}) were detected on cooling of the heated samples, either in pure form or as a mixture.

Renlund, Anita Mariana; Tappan, Alexander Smith; Miller, Jill C.

2000-11-01T23:59:59.000Z

404

Magnetic field effect on stimulated Raman scattering of electromagnetic waves from nanoparticle lattice  

SciTech Connect

The influence of a static magnetic field on the Raman scattering of a millimeter pump wave propagating through periodic nanoparticles is studied. Formulas for the growth rate of the scattered electromagnetic wave and the electrostatic wave are derived and analyzed. It is found that the growth rate for the backscattering case is larger than that of forward scattering and the growth rate is increased by the static magnetic field. A resonance in the dispersion relation of the electromagnetic wave is found as a combination of the cyclotron and plasma frequency. However, no instability was found for this lower branch of the dispersion curve.

Chakhmachi, A. [Plasma Physics and Nuclear Fusion Research School, Nuclear Science and Technology Research Institute, P.O. Box 14155-1339, Tehran (Iran, Islamic Republic of); Maraghechi, B. [Department of Physics, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran (Iran, Islamic Republic of)

2011-02-15T23:59:59.000Z

405

Coherent Anti-Stokes Raman Spectroscopy of Radio-Frequency Discharge Plasmas of Silane and Disilane  

Science Journals Connector (OSTI)

Coherent anti-Stokes Raman spectroscopy has been employed for the diagnosis of rf discharges of silane (SiH4) and disilane (Si2H6). The signal intensities from silane and disilane have been measured as a function of time after switching-on the rf power supplied to SiH4 and Si2H6 gas in a closed reaction chamber. From this measurement, the loss rates of silane and disilane have been determined directly as functions of the rf-power density and gas pressure for the first time. The rate of formation of SiH4 in disilane discharge plasmas has also been determined.

Nobuhiro Hata; Akihisa Matsuda; Kazunobu Tanaka

1986-01-01T23:59:59.000Z

406

Demonstration of triple pump coherent anti-Stokes Raman scattering in a jet diffusion flame  

E-Print Network (OSTI)

. A. Theory 1. Coherent anti-Stokes Raman scattering basics B. Dual-pump and triple-pump CARS processes 1. Dual-pump CARS 2. Triple pump CARS C. Thermometry and species detection EXPERIMENTAL APPARATUS A. Initial experimental system 1. Laser.... Laser Alignment and Performance I . Nd: YAG laser 2. Narrow band dye laser (ND6000) alignment 3. Broad-band dye laser alignment B. Triple-pump CARS set-up 1. CARS phase-matching alignment 2. Diffusion flame burner C. Results I. Results from first...

Velur Natarajan, Viswanathan

2012-06-07T23:59:59.000Z

407

Entangled radiation via a Raman-driven quantum-beat laser  

E-Print Network (OSTI)

with 1 and 2 being the cavity decay rates of modes 1 and 2, respectively. Here, #11;11 and #11;22 are the linear gain coefficients, whereas #11;12 and #11;21 are the phase-sensitive cross-coupling coefficients that are generated due to the atomic... coherence produced between the levels #8;b1#7; and #8;b2#7; via the two-photon Raman process using two strong driving fields. Explicit expressions for the coefficients #11;11, #11;12, #11;21, and #11;22 in Eq. #1;7#2; are given in Appendix B. The phase...

Qamar, Sajid; Al-Amri, M.; Qamar, Shahid; Zubairy, M. Suhail

2009-01-01T23:59:59.000Z

408

Studies of the Raman Spectra of Cyclic and Acyclic Molecules: Combination and Prediction Spectrum Methods  

SciTech Connect

A combination of Raman spectroscopy and density functional methods was employed to investigate the spectral features of selected molecules: furfural, 5-hydroxymethyl furfural (HMF), methanol, acetone, acetic acid, and levulinic acid. The computed spectra and measured spectra are in excellent agreement, consistent with previous studies. Using the combination and prediction spectrum method (CPSM), we were able to predict the important spectral features of two platform chemicals, HMF and levulinic acid.The results have shown that CPSM is a useful alternative method for predicting vibrational spectra of complex molecules in the biomass transformation process.

Kim, Taijin; Assary, Rajeev S.; Marshall, Christopher L.; Gosztola, David J.; Curtiss, Larry A.; Stair, Peter C.

2012-04-02T23:59:59.000Z

409

Glucose concentration measured by the hybrid coherent anti-Stokes Raman-scattering technique  

E-Print Network (OSTI)

PHYSICAL REVIEW A 81, 013813 (2010) Glucose concentration measured by the hybrid coherent anti-Stokes Raman-scattering technique Xi Wang, Aihua Zhang, Miaochan Zhi, Alexei V. Sokolov, and George R. Welch Department of Physics and Institute... is controlled by two translation stages (DS1 and DS2 in Fig. 1). They overlap at their focuses either in a crossing-beam configuration (Figs. 3, 4, and 7) as in Fig. 1 1050-2947/2010/81(1)/013813(6) 013813-1 ?2010 The American Physical Society WANG, ZHANG...

Wang, Xi; Zhang, Aihua; Zhi, Miaochan; Sokolov, Alexei V.; Welch, George R.

2010-01-01T23:59:59.000Z

410

Methods and systems for Raman and optical cross-interrogation in flow-through silicon membranes  

DOE Patents (OSTI)

Cross-interrogating photonic detection systems and methods are shown. A flow through photonic crystal membrane with a surface enhanced Raman scattering (SERS) substrate is provided with pores which are distributed along multiple regions. The pores of one region have walls to which a first type of target specific anchor can be attached, while pores of another region have walls to which a second type of target specific anchor can be attached. An optical arrangement out-of-plane to the SERS substrate is also provided for enhanced sensitivity and identification of target organisms.

Bond, Tiziana C.; Letant, Sonia E.

2014-09-09T23:59:59.000Z

411

Combined raman and IR fiber-based sensor for gas detection  

DOE Patents (OSTI)

A double-pass fiber-optic based spectroscopic gas sensor delivers Raman excitation light and infrared light to a hollow structure, such as a hollow fiber waveguide, that contains a gas sample of interest. A retro-reflector is placed at the end of this hollow structure to send the light back through the waveguide where the light is detected at the same end as the light source. This double pass retro reflector design increases the interaction path length of the light and the gas sample, and also reduces the form factor of the hollow structure.

Carter, Jerry C; Chan, James W; Trebes, James E; Angel, Stanley M; Mizaikoff, Boris

2014-06-24T23:59:59.000Z

412

[Laser flash photolysis, EPR and Raman studies of liquids at elevated pressures  

SciTech Connect

The proposed research will solve a number of analytical chemical problems in solutions with measurement techniques that benefit from the use of elevated hydrostatic pressures: stopped-flow spectrophotometry (Gd[sup 3+] + L(ligand), [RuL[sub 5]H[sub 2]O][sup 2+], laser flash photolysis of Mo(CO)[sub 6] + L, flash photolysis of binuclear metalloproteins), EPR spectroscopy (Gd[sup 3+] ion-exchanged into ETS-10 and ETAS-10 molecular sieves), laser flash photolysis kinetic studies of Mo(CO)[sub 6]-2,2'-bipyridine, and electrochemical studies of metalloporphyrins using resonance Raman spectroscopy.

Eyring, E.M.

1992-01-01T23:59:59.000Z

413

[Laser flash photolysis, EPR and Raman studies of liquids at elevated pressures  

SciTech Connect

The proposed research will solve a number of analytical chemical problems in solutions with measurement techniques that benefit from the use of elevated hydrostatic pressures: stopped-flow spectrophotometry (Gd{sup 3+} + L(ligand), [RuL{sub 5}H{sub 2}O]{sup 2+}, laser flash photolysis of Mo(CO){sub 6} + L, flash photolysis of binuclear metalloproteins), EPR spectroscopy (Gd{sup 3+} ion-exchanged into ETS-10 and ETAS-10 molecular sieves), laser flash photolysis kinetic studies of Mo(CO){sub 6}-2,2`-bipyridine, and electrochemical studies of metalloporphyrins using resonance Raman spectroscopy.

Eyring, E.M.

1992-10-01T23:59:59.000Z

414

Trapped-Particle Instability Leading to Bursting in Stimulated Raman Scattering Simulations  

SciTech Connect

Nonlinear, kinetic simulations of Stimulated Raman Scattering (SRS) for laser-fusion-relevant conditions present a bursting behavior. Different explanations for this regime has been given in previous studies: Saturation of SRS by increased nonlinear Landau damping [K. Estabrook et al., Phys. Fluids B 1 (1989) 1282] and detuning due to the nonlinear frequency shift of the plasma wave [H.X. Vu et al., Phys. Rev. Lett. 86 (2001) 4306]. Another mechanism, also assigning a key role to the trapped electrons, is proposed here: The break-up of the plasma wave through the trapped-particle instability.

S. Brunner; E. Valeo

2001-11-08T23:59:59.000Z

415

Spectroscopic prescription for optimal stimulated Raman transfer of ultracold heteronuclear molecules to the lowest rovibronic level  

Science Journals Connector (OSTI)

We show that the multiplicative product of a molecular-beam excitation spectrum and an ultracold-molecule excitation spectrum, with a frequency offset appropriate to the initial ultracold-molecule level, provides the relative rate of stimulated Raman transfer (SRT) from a given high rovibrational level to the lowest rovibronic level, i.e., the v??=0,J??=0 level of the ground electronic state for photoassociated (and magnetoassociated) ultracold molecules. This product spectrum clearly indicates the optimal pathways for SRT, even when the two component spectra are completely unassigned. We illustrate this specifically for the case of KRb.

Jin-Tae Kim; Yonghoon Lee; Bongsoo Kim; Dajun Wang; William C. Stwalley; Phillip L. Gould; Edward E. Eyler

2011-12-21T23:59:59.000Z

416

Raman-assisted DPP-BOTDA sensor employing Simplex coding with sub-meter scale spatial resolution over 93 km standard SMF  

E-Print Network (OSTI)

Raman-assisted DPP-BOTDA sensor employing Simplex coding with sub-meter scale spatial resolution technique is combined with bi-directional Raman amplification and Simplex coding to achieve sub-meter successfully employed to attain sub-meter spatial resolution [1-3], although typically exhibiting limited

Thévenaz, Jacques

417

Time-resolved coherent anti-Stokes Raman-scattering measurements of I2 in solid Kr: Vibrational dephasing on the ground electronic state  

E-Print Network (OSTI)

Time-resolved coherent anti-Stokes Raman-scattering measurements of I2 in solid Kr: Vibrational; published online 18 August 2005 Time-resolved coherent anti-Stokes Raman-scattering CARS measurements are carried out for iodine I2 in solid krypton matrices. The dependence of vibrational dephasing time

Apkarian, V. Ara

418

Light-induced oxygen-ordering dynamics in ,,Y,Pr...Ba2Cu3O6.7: A Raman spectroscopy and Monte Carlo study  

E-Print Network (OSTI)

Light-induced oxygen-ordering dynamics in ,,Y,Pr...Ba2Cu3O6.7: A Raman spectroscopy and Monte Carlo energy barrier which impedes oxygen movement in the plane unless the oxygen atoms are excited by light for oxygen reordering in the chain plane being at the origin of Raman photobleaching and related effects. DOI

Nabben, Reinhard

419

Crystallinity and compositional changes in carbonated apatites: Evidence from {sup 31}P solid-state NMR, Raman, and AFM analysis  

SciTech Connect

Solid-state (magic-angle spinning) NMR spectroscopy is a useful tool for obtaining structural information on bone organic and mineral components and synthetic model minerals at the atomic-level. Raman and {sup 31}P NMR spectral parameters were investigated in a series of synthetic B-type carbonated apatites (CAps). Inverse {sup 31}P NMR linewidth and inverse Raman PO{sub 4}{sup 3?}?{sub 1} bandwidth were both correlated with powder XRD c-axis crystallinity over the 0.3–10.3 wt% CO{sub 3}{sup 2?} range investigated. Comparison with bone powder crystallinities showed agreement with values predicted by NMR and Raman calibration curves. Carbonate content was divided into two domains by the {sup 31}P NMR chemical shift frequency and the Raman phosphate ?{sub 1} band position. These parameters remain stable except for an abrupt transition at 6.5 wt% carbonate, a composition which corresponds to an average of one carbonate per unit cell. This near-binary distribution of spectroscopic properties was also found in AFM-measured particle sizes and Ca/P molar ratios by elemental analysis. We propose that this transition differentiates between two charge-balancing ion-loss mechanisms as measured by Ca/P ratios. These results define a criterion for spectroscopic characterization of B-type carbonate substitution in apatitic minerals. - Graphical abstract: Carbonated apatite shows an abrupt change in spectral (NMR, Raman) and morphological (AFM) properties at a composition of about one carbonate substitution per unit cell. Display Omitted - Highlights: • Crystallinity (XRD), particle size (AFM) of carbonated apatites and bone mineral. • Linear relationships among crystallinity, {sup 31}P NMR and Raman inverse bandwidths. • Low and high carbonated apatites use different charge-balancing ion-loss mechanism.

McElderry, John-David P.; Zhu, Peizhi [Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055 (United States); Mroue, Kamal H. [Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055 (United States); Department of Biophysics, University of Michigan, Ann Arbor, MI 48109-1055 (United States); Xu, Jiadi [Department of Biophysics, University of Michigan, Ann Arbor, MI 48109-1055 (United States); Pavan, Barbara [Department of Chemistry and Science of Advanced Materials Program, Central Michigan University, Mt. Pleasant, MI 48859 (United States); Fang, Ming [Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055 (United States); Zhao, Guisheng; McNerny, Erin; Kohn, David H.; Franceschi, Renny T. [School of Dentistry, University of Michigan, Ann Arbor, MI 48109-1055 (United States); Holl, Mark M.Banaszak [Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055 (United States); Tecklenburg, Mary M.J., E-mail: mary.tecklenburg@cmich.edu [Department of Chemistry and Science of Advanced Materials Program, Central Michigan University, Mt. Pleasant, MI 48859 (United States); Ramamoorthy, Ayyalusamy [Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055 (United States); Department of Biophysics, University of Michigan, Ann Arbor, MI 48109-1055 (United States); Morris, Michael D. [Department of Chemistry, University of Michigan, Ann Arbor, MI 48109-1055 (United States)

2013-10-15T23:59:59.000Z

420

Schumann-Runge resonance Raman scattering of O sub 2 : A rotationally resolved excitation profile study  

SciTech Connect

Rotationally resolved resonance Raman spectra and excitation profiles of O{sub 2} excited with narrow-band radiation tunable throughout the {nu}{prime} = 5 absorption band of the Schumann-Runge (SR) region (190-192 nm) are reported. The pressure dependence and scattering polarization unambiguously identify all the observed resonant emission intensity as Raman scattering (both resonant and off-resonant), not resonance fluorescence. This characterization is in contrast to the description of the resonant emission of the SR absorption bands offered in recent laser-excited studies. Excitation profile analysis determines rotationally specific lifetimes of the {nu}{prime} = 5 level. A homogeneous line width of 2.05 {plus minus} 0.10 cm{sup {minus}1} is determined for the rotational levels of this vibronic band. Within experimental uncertainty, this line width/lifetime is independent of the rotational angular momentum of the resonant predissociative rovibronic levels of the {nu}{prime} = 5 band. This value is in excellent agreement with the results of the most recent SR absorption contour analysis but is not in quantitative agreement with the most recent theoretical modeling of the rovibronic dynamics of the SR absorption bands.

Zhang, Y.P.; Ziegler, L.D. (Northeastern Univ., Boston, MA (USA))

1989-09-07T23:59:59.000Z

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
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421

Raman scattering studies of the GaAs native oxide interface  

Science Journals Connector (OSTI)

Oxide filmsgrown by heat treatment on the 100 and 111 faces of GaAs have been studied by Raman backscattering. A spectrum consisting of the bulk LO and TO lines of GaAs and two additional lines labeled R1 and R2 is observed on all samples prepared at temperatures above 435° C. The additional modes are attributed to an interface region of perhaps several hundred angstroms thickness beneath the oxide film. This structure appears to be made unstable by chemical removal of the film. After the film is removed the spectrum is annealed (returns to that of GaAs) in a matter of weeks at room temperature and in about 1 h at 400° C whether the annealing atmosphere is N2 O2 or forming gas. One of the modes R2 appears to scatter as a scalar i.e. a diagonal Raman matrix element. Spectra by the R1 mode on the other hand appear to be largely unpolarized or possibly slightly nondiagonal in character. Some speculations about the possible nature of the interface region are presented.

J. A. Cape; W. E. Tennant; L. G. Hale

1977-01-01T23:59:59.000Z

422

Theory of odd torsional transitions in the V - N resonance Raman spectrum of ethylene  

SciTech Connect

The V - N resonance Raman spectrum of ethylene shows a long progression in even quanta of the ground-state torsional mode {nu}{sub 4}{double_prime}(a{sub u}). Bands approximately midway between the even quanta have been assigned to transitions to odd quanta of {nu}{sub 4}{double_prime}. Such transitions are forbidden according to the disallowed g-u selection rule of Raman spectroscopy. Here, the authors consider the theory of the intensity of such transitions allowing for the fact that the excited state is twisted by 90{degrees} at equilibrium, using Hougen`s double group theory. From approximate one- dimensional torsional potentials of the V and N electronic states, it is shown that good qualitative agreement between observed and calculated intensities is obtained. The electronic transition moment is assumed to be proportional to cos{theta}, where {theta} is the torsional angle, but the calculated relative intensities are not sensitive to the precise torsional dependence. More detailed theory will require consideration of the avoided crossing affecting the V state.

Watson, J.K.G.; Siebrand, W.; Zgierski, M.Z. [Steacie Institute for Molecular Sciences, Ottawa, Ontario (Canada)] [and others

1996-12-31T23:59:59.000Z

423

Sorption Mechanisms of Antibiotic Cephapirin onto Quartz and Feldspar by Raman Spectroscopy  

SciTech Connect

Raman spectroscopy was used to investigate the sorption mechanisms of cephapirin (CHP), a veterinary antibiotic, onto quartz (SiO2) and feldspar (KAlSi3O8) at different pH values. Depending on the charge and surface properties of the mineral, different reaction mechanisms including electrostatic attraction, monodentate and bidentate complexation were found to be responsible for CHP sorption. The zwitterion (CHPo) adsorbs to a quartz(+) surface by electrostatic attraction of the carboxylate anion group ( COO-) at a low pH, but adsorbs to a quartz(-) surface through electrostatic attraction of the pyridinium cation and possibly COO- bridge complexes at relatively higher pH conditions. CHP- bonds to a quartz(-) surface by bidentate complexation between one oxygen of COO- and oxygen from the carbonyl (C=O) of the acetoxymethyl group. On a feldspar surface of mixed charge, CHPo forms monodentate complexes between C=O as well as COO- bridging complexes or electrostatically attached to localized edge (hydr)oxy-Al surfaces. CHP- adsorbs to feldspar(-) through monodentate C=O complexation, and similar mechanisms may operate for the sorption of other cephalosporins. This research demonstrates, for the first time, that Raman spectroscopic techniques can be effective for evaluating the sorption processes and mechanisms of cephalosporin antibiotics even at relatively low sorbed concentrations (97-120 ?mol/kg).

Peterson, Jonathan [Hope College; Wang, Wei [ORNL; Gu, Baohua [ORNL

2009-01-01T23:59:59.000Z

424

Growth process of microcrystalline silicon studied by combined photoluminescence and Raman investigations  

SciTech Connect

Plasma enhanced chemical vapor deposition of silicon on glass substrates leads to formation of silicon amorphous films with partial crystallization of nano-grains in the amorphous matrix. We studied the transition of amorphous to microcrystalline silicon during such deposition. Formation of silicon nano-grains was detected by means of photoluminescence and Raman spectroscopy. The crystalline fraction and the mean size of the nano-grains were estimated by the position and the intensity of the peaks in the Raman spectrum. We showed that the fraction of crystalline silicon in the layers and the size of the nano-grains are strongly dependent on the growth conditions. The photoluminescence spectra exhibit distinct features related to recombination in the amorphous and in the crystalline phases. A significant narrowing of the photoluminescence peak related to the amorphous phase with increasing crystalline fraction indicates a structural modification in the amorphous silicon. It suggests an ordering process occurring before the start of the actual crystallization. A peak at about 1.4 eV was associated with isolated nano-crystalline grains within the amorphous matrix. A correlation between the peak energy and grain size was found, indicating effects of carrier quantum confinement. The experimental results confirm the established theoretical models for growth of microcrystalline silicon films.

Klossek, A.; Mankovics, D.; Ratzke, M. [Brandenburg University of Technology, Konrad-Wachsmann-Allee 1, D-03046 Cottbus (Germany)] [Brandenburg University of Technology, Konrad-Wachsmann-Allee 1, D-03046 Cottbus (Germany); Arguirov, T.; Kittler, M. [Brandenburg University of Technology, Konrad-Wachsmann-Allee 1, D-03046 Cottbus (Germany) [Brandenburg University of Technology, Konrad-Wachsmann-Allee 1, D-03046 Cottbus (Germany); IHP Microelectronics, Im Technologiepark 25, D-15236 Frankfurt (Oder) (Germany); Kirner, S.; Gabriel, O.; Stannowski, B.; Schlatmann, R. [Competence Centre Thin-Film- and Nanotechnology for Photovoltaics Berlin, Helmholtz-Zentrum Berlin, Berlin (Germany)] [Competence Centre Thin-Film- and Nanotechnology for Photovoltaics Berlin, Helmholtz-Zentrum Berlin, Berlin (Germany); Friedrich, F. [Competence Centre Thin-Film- and Nanotechnology for Photovoltaics Berlin, Helmholtz-Zentrum Berlin, Berlin (Germany) [Competence Centre Thin-Film- and Nanotechnology for Photovoltaics Berlin, Helmholtz-Zentrum Berlin, Berlin (Germany); Department of Semiconductor Devices, Technische Universität Berlin, Sekr. E2, Einsteinufer 19, D-10587 Berlin (Germany)

2013-12-14T23:59:59.000Z

425

Polymorphism in Photoluminescent KNdW2O8: Synthesis, Neutron Diffraction, and Raman Study  

SciTech Connect

Polymorphs of KNdW2O8 ( -KNdW2O8 and -KNdW2O8) phosphors were synthesized by an efficient solution combustion technique for the first time. The crystal structure of the polymorphs analyzed from Rietveld refinement of neutron diffraction data confirms that -KNdW2O8 crystallizes in the tetragonal system (space group I4 ), and -KNdW2O8 crystallizes in the monoclinic system (space group C2/m). The local structure of both polymorphs was elucidated using combined neutron pair distribution function (PDF) and Raman scattering techniques. Photoluminescence measurements of the polymorphs showed broadened emission line width and increased intensity for -KNdW2O8 in the visible region compared to -KNdW2O8. This phenomenon is attributed to the increased distortion in the coordination environment of the luminescing Nd3+ ion. Combined PDF, Rietveld, and Raman measurements reveal distortions of the WO6 octahedra and NdO8 polyhedra in -KNdW2O8. This crystal structure photoluminescence study suggests that this class of tungstates can be exploited for visible light emitting devices by tuning the crystal symmetry.

S. M. Bhat, Swetha [Materials Science Division, Poornaprajna Institute of Scientific Research, Bidalur Near Devanahalli,; Swain, Diptikanta [CPMU, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru, Karnataka, India] [CPMU, Jawaharlal Nehru Centre for Advanced Scientific Research, Jakkur, Bengaluru, Karnataka, India; Feygenson, Mikhail [ORNL] [ORNL; Neuefeind, Joerg C [ORNL] [ORNL; Sundaram, Nalini [Materials Science Division, Poornaprajna Institute of Scientific Research, Bidalur Near Devanahalli,] [Materials Science Division, Poornaprajna Institute of Scientific Research, Bidalur Near Devanahalli,

2014-01-01T23:59:59.000Z

426

Raman and XPS characterization of fuel-cladding interactions using miniature specimens  

SciTech Connect

Laser Raman spectroscopy was evaluated as a tool for studying fuel-cladding chemical interactions at elevated temperatures. Materials and conditions were selected to simulate the interface of oxide fuels and fission products with high-temperature cladding materials for TRU-MOX fueled reactors. Both ex-situ and in-situ spectroscopy measurements were performed using polished HT-9 disks, uncoated and coated with yttria-stabilized zirconia, that were exposed to air oxidation at temperatures between 873-973K. Ex-situ measurements (under ambient conditions) were conducted to identify oxide phases, determine oxidation mechanisms and approximate film growth rates with an optimal signal-to-noise for the equipment used. Subsequently performed in-situ measurements were used to evaluate the sensitivity of the technique for measurements at elevated temperature in a hot-stage. Raman spectra were supported with x-ray photoelectron spectroscopy depth profiling. The results, which are for non-fueled materials in this study, illustrated a method for fast screening of candidate alloys with actinide-based MOX fuel mixtures.

Windisch, Charles F.; Henager, Charles H.; Engelhard, Mark H.; Bennett, Wendy D.

2009-01-01T23:59:59.000Z

427

Accelerated Testing of HT-9 with Zirconia Coatings Containing Gallium using Raman Spectroscopy and XPS  

SciTech Connect

Laser Raman spectroscopy and x-ray photoelectron spectroscopy were used to study the evolution of composition of oxide films in the presence of zirconia coatings on miniature HT-9 alloy specimens subjected to elevated temperature in air. The experiments expanded on previous efforts to develop a quick-screening technique for candidate alloys for cladding materials (HT-9) and actinide-based mixed oxide fuel mixtures (represented by the zirconia coating) by investigating the effect of both coating composition and alloy pretreatment conditions on the high temperature reactions. In particular, the presence of the element Ga (a potential impurity in mixed oxide fuel) in the initial zirconia coating was found to accelerate the rate of oxide growth relative to that of yttria-stabilized zirconia studied previously. In addition, HT-9 samples that were subjected to different thermal pretreatments gave different results. The results suggest that the presence of Ga in a mixed oxide fuel will enhance the corrosion of HT-9 cladding under the conditions of this study, although the extent of enhancement is influenced by thermal pretreatment of the cladding material. The results also demonstrate the need to combine Raman spectroscopy with other techniques, particularly photoelectron spectroscopy, for optimizing composition and/or fabrication conditions of both cladding and oxide fuels for advanced nuclear reactors.

Windisch, Charles F.; Henager, Charles H.; Engelhard, Mark H.; Bennett, Wendy D.

2009-12-01T23:59:59.000Z

428

A narrow window of Rabi frequency for competition between electromagnetically induced transparency and Raman absorption  

SciTech Connect

This investigation clarifies the transition phenomenon between the electromagnetically induced transparency (EIT) and Raman absorption in a ladder-type system of Doppler-broadened cesium vapor. A competition window of this transition was found to be as narrow as 2 MHz defined by the probe Rabi frequency. For a weak probe, the spectrum of EIT associated with quantum interference suggests that the effect of the Doppler velocity on the spectrum is negligible. When the Rabi frequency of the probe becomes comparable with the effective decay rate, an electromagnetically induced absorption (EIA) dip emerges at the center of the power broadened EIT peak. While the Rabi frequency of the probe exceeds the effective decay rate, decoherence that is generated by the intensified probe field occurs and Raman absorption dominates the interaction process, yielding a pure absorption spectrum; the Doppler velocity plays an important role in the interaction. A theory that is based on density matrix simulation, with or without the Doppler effect, can qualitatively fit the experimental data. In this work, the coherence of atom-photon interactions is created or destroyed using the probe Rabi frequency as a decoherence source.

Chang, Ray-Yuan; Fang, Wei-Chia; Lee, Ming-Tsung; He, Zong-Syun; Ke, Bai-Cian [Department of Physics, National Cheng-Kung University, Tainan 70101, Taiwan (China); Lee, Yi-Chi [Institute of Electro-Optical Science and Engineering, National Cheng-Kung University, Tainan 70101, Taiwan (China); Tsai, Chin-Chun [Department of Physics, National Cheng-Kung University, Tainan 70101, Taiwan (China); Institute of Electro-Optical Science and Engineering, National Cheng-Kung University, Tainan 70101, Taiwan (China)

2010-01-15T23:59:59.000Z

429

A high-resolution large-acceptance analyzer for X-ray fluorescence and Raman spectroscopy  

SciTech Connect

A newly designed multi-crystal X-ray spectrometer and its applications in the fields of X-ray fluorescence and X-ray Raman spectroscopy are described. The instrument is based on 8 spherically curved Si crystals, each with a 3.5 inch diameter form bent to a radius of 86 cm. The crystals are individually aligned in the Rowland geometry capturing a total solid angle of 0.07 sr. The array is arranged in a way that energy scans can be performed by moving the whole instrument, rather than scanning each crystal by itself. At angles close to back scattering the energy resolution is between 0.3 and 1 eV depending on the beam dimensions at the sample. The instrument is mainly designed for X-ray absorption and fluorescence spectroscopy of transition metals in dilute systems such as metalloproteins. First results of the Mn K{beta} (3p -> 1s) emission in photosystem II are shown. An independent application of the instrument is the technique of X-ray Raman spectroscopy which can address problems similar to those in traditional soft X-ray absorption spectroscopies, and initial results are presented.

Bergmann, Uwe; Cramer, Stephen P.

2001-08-02T23:59:59.000Z

430

Resonance Raman Analysis of the Mechanism of Energy Storage and Chromophore Distortion in the Primary Visual Photoproduct  

E-Print Network (OSTI)

Resonance Raman Analysis of the Mechanism of Energy Storage and Chromophore Distortion modes and their relation to energy storage in the primary photoproduct. Low-temperature (77 K) resonance interactions of the 9- and 13-methyl groups with surrounding residues. This distortion stores light energy

Chang, Belinda

431

Reversible Temperature Dependence in Surface-Enhanced Raman Scattering of 1-Propanethiol Adsorbed on a Silver Island Film  

E-Print Network (OSTI)

Reversible Temperature Dependence in Surface-Enhanced Raman Scattering of 1-Propanethiol Adsorbed scattering (SERS) of 1-propanethiol adsorbed on a silver film prepared chemically has been measured over of various metals prepared by many different ways for a wide variety of adsorbate molecules.2 Intensive

Kim, Myung Soo

432

58 IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT, VOL. 53, NO. 1, FEBRUARY 2004 Multichannel Raman Gas Analyzer: The Data  

E-Print Network (OSTI)

with the green laser source previously used and reported in a related article. Index Terms--Air-pollution, data Raman Gas Analyzer: The Data Acquisition and Control System. Measurement Improvement With Blue Laser Albrecht, and Nikiforos G. Theofanous Abstract--In this paper, the data acquisition and control system

Athens, University of

433

Intensities of the Raman-active modes in single and multiwall nanotubes S. Reich and C. Thomsen  

E-Print Network (OSTI)

of recent experiments on aligned nanotubes we calculate the relative intensities for the high-energy modes of the nanotubes and on the excitation energy. As was shown by Milnera et al.3 the radial breathing modeIntensities of the Raman-active modes in single and multiwall nanotubes S. Reich and C. Thomsen

Nabben, Reinhard

434

Investigation of the thermal stability of phosphotungstic Wells-Dawson heteropoly-acid through in situ Raman spectroscopy  

SciTech Connect

Highlights: {yields} Insitu Raman is used to monitor the thermal stability of Wells Dawson heteropolyacid. {yields} TP-Raman follows the gradual dehydration and the effect on the secondary structure. {yields} Wells-Dawson heteropolyacid does not decompose into Keggin and WO{sub 3} units below 600{sup o}C -- Abstract: The present investigation applies laser Raman spectroscopy under in situ conditions to obtain insights on the effect of the temperature on the molecular structure of the bulk phosphotungstic Wells-Dawson heteropoly-acid H{sub 6}P{sub 2}W{sub 18}O{sub 62}.xH{sub 2}O (HPA). The in situ temperature-programmed studies followed the evolution of phosphotungstic Wells-Dawson and Keggin heteropoly-acids along with tungsten trioxide under controlled atmosphere and temperature. The spectroscopic investigation of the Wells-Dawson HPA demonstrated that in situ Raman spectroscopy is a suitable technique to follow the effect of a gradual dehydration on the secondary structure of such a complex structure. Moreover, the absence of the signals belonging either to the Keggin or WO{sub 3} phases provides further evidence that the phosphotungstic heteropolyanion does not decomposes towards those materials at temperatures below 600 {sup o}C.

Matkovic, Silvana Raquel, E-mail: matkovic@quimica.unlp.edu.ar [Centro de Investigacion y Desarrollo en Ciencias Aplicadas-Dr. Jorge J. Ronco. U.N.L.P., CONICET, CCT La Plata. Calle 47 N 257, B1900AJK La Plata, Buenos Aires (Argentina); Briand, Laura Estefania [Centro de Investigacion y Desarrollo en Ciencias Aplicadas-Dr. Jorge J. Ronco. U.N.L.P., CONICET, CCT La Plata. Calle 47 N 257, B1900AJK La Plata, Buenos Aires (Argentina)] [Centro de Investigacion y Desarrollo en Ciencias Aplicadas-Dr. Jorge J. Ronco. U.N.L.P., CONICET, CCT La Plata. Calle 47 N 257, B1900AJK La Plata, Buenos Aires (Argentina); Banares, Miguel Angel [Laboratorio de Espectroscopia Catalitica, Instituto de Catalisis y Petroleoquimica, CSIC. Marie Curie 2, Cantoblanco, E-28049 Madrid (Spain)] [Laboratorio de Espectroscopia Catalitica, Instituto de Catalisis y Petroleoquimica, CSIC. Marie Curie 2, Cantoblanco, E-28049 Madrid (Spain)

2011-11-15T23:59:59.000Z

435

Analysis of polyethylene wear debris using micro-Raman spectroscopy: A report on the presence of beta-carotene  

E-Print Network (OSTI)

Analysis of polyethylene wear debris using micro-Raman spectroscopy: A report on the presence- high molecular weight polyethylene wear debris isolated from revised knee replacements. The novel the chemical nature of individual, retrieved polyethylene particles. The analysis revealed the presence

Hahn, David W.

436

TIME-RESOLVED RAMAN SPECTROSCOPY OF MARS ANALOG MINERALS AND ORGANICS. J. Blacksberg1 Y. Maruyama1  

E-Print Network (OSTI)

1 , E. Alerstam1 , C. Cochrane1 , G.R.Rossman2 , S. Shkolyar3 , J. Farmer3 , 1 Jet Propulsion, California 91125, grr@gps.caltech.edu. 3 School of Earth and Space Exploration, Arizona State University are identified, Raman spectroscopy has the potential to map out minerals on the grain scale and potentially find

Rossman. George R.

437

A Raman Spectrographic and Potentiometric Study of Aqueous Lithium and Potassium Acetate Complexation at Temperatures from 20 to 200 ?C  

Science Journals Connector (OSTI)

The Raman spectra of aqueous NaOH–CH3COOH solution containing either LiCl or KCl were collected at temperatures from 20 to 200 ?C. Interpretation of these spectra reveals significant aqueous LiCH3COO0 formation, ...

Patricia Fournier; Robert Gout; Eric H. Oelkers

2005-08-01T23:59:59.000Z

438

Raman Spectroscopy—An Innovative and Versatile Tool To Follow the Respirational Activity and Carbonate Biomineralization of Important Cave Bacteria  

Science Journals Connector (OSTI)

Raman Spectroscopy—An Innovative and Versatile Tool To Follow the Respirational Activity and Carbonate Biomineralization of Important Cave Bacteria ... (11) Bacterial calcium carbonate formation is applied in contaminated soil and groundwater remediation,(12) the protection and repair of concrete and cement structures,(13) and the conservation of building stone and statuary. ...

Robert Keiner; Torsten Frosch; Stefan Hanf; Anna Rusznyak; Denise M. Akob; Kirsten Küsel; Jürgen Popp

2013-08-23T23:59:59.000Z

439

Extended Near-Infrared Resonance Raman Investigations of an Organic Mixed-Valence System: Diazatetracyclodiene Radical Cation  

E-Print Network (OSTI)

Extended Near-Infrared Resonance Raman Investigations of an Organic Mixed-Valence System near-infrared region show that six modes are coupled to the intramolecular charge-transfer transition transfer (IVCT) absorption bands in the red to near- infrared region of the spectrum, which are, at least

440

Influence of glass polymerisation and oxidation on micro-Raman water analysis in alumino-silicate glasses  

E-Print Network (OSTI)

Influence of glass polymerisation and oxidation on micro-Raman water analysis in alumino-silicate glasses Maxime Merciera, Andrea Di Muroab , Daniele Giordanoc , Nicole Métricha , Priscille Lesned of an accurate analytical procedure for determination of dissolved water in complex alumino-silicate glasses via

Paris-Sud XI, Université de

Note: This page contains sample records for the topic "raman lidar profiles-temperature" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Raman spectroscopy of iron oxides and (oxy)hydroxides at low laser power and possible applications in environmental magnetic studies  

Science Journals Connector (OSTI)

......example measured by Kelemen Fang (2001) in coal and by Tan et al. (2007) in graphite...Stanjek of the Institute of Mineralogy and Economic Geology, Aachen University. Two people...trends in Raman spectra from kerogen and coal, Energy Fuels, 15, 653-658. Lee A......

Monika Hanesch

2009-06-01T23:59:59.000Z

442

March 15, 2001 / Vol. 26, No. 6 / OPTICS LETTERS 361 Raman-excited spin coherences in nitrogen-vacancy  

E-Print Network (OSTI)

March 15, 2001 / Vol. 26, No. 6 / OPTICS LETTERS 361 Raman-excited spin coherences in nitrogen-vacancy coherences were experimentally observed in nitrogen-vacancy (N-V) diamond color centers by means we chose to use nitrogen-vacancy (N-V) color centers9 in diamond because they have a large optical

Shahriar, Selim

443

Numerical coupling of Landau damping and Raman amplification. R. Belaouar1,2, T. Colin2, G. Gallice1  

E-Print Network (OSTI)

nuclear fusion by inertial confinement in a laboratory. We therefore need some accurate and reliable model for laser-plasma interaction involving Raman instability and Landau damping. This model exhibits;1 Introduction and physical context The interaction of an intense laser pulse with a plasma is a complex physical

Boyer, Edmond

444

FTIR and Raman Study of LixTiyMn1-y2(y=0,0.11) Cathodes in  

NLE Websites -- All DOE Office Websites (Extended Search)

FTIR and Raman Study of LixTiyMn1-y2(y=0,0.11) Cathodes in FTIR and Raman Study of LixTiyMn1-y2(y=0,0.11) Cathodes in Pyrrolidinium-based Ionic Liquid Electrolyte Systems Title FTIR and Raman Study of LixTiyMn1-y2(y=0,0.11) Cathodes in Pyrrolidinium-based Ionic Liquid Electrolyte Systems Publication Type Journal Article Year of Publication 2009 Authors Hardwick, Laurence J., Juliette A. Saint, Ivan T. Lucas, Marca M. Doeff, and Robert Kostecki Journal J. Electrochemical Society Volume 156 Issue 2 Pagination A120-A127 Keywords electrochemical electrodes, Fourier transform spectra, infrared spectra, lithium compounds, manganese compounds, Raman spectra, titanium compounds Abstract This work demonstrates the protective effect of partial titanium substitution in LixTi0.11Mn0.89O2 against surface decomposition in room-temperature ionic liquid (RTILs) cells. Raman microscopy and reflectance Fourier transform IR (FTIR) spectroscopy were used to analyze electrodes recovered from cycled Li/LixTiyMn1-yO2 (y=0,0.11) cells containing the 0.5mol/kg LiTFSI in P13FSI RTIL electrolyte. [TFSI=bis(trifluoromethanesulfonyl)imide .] Raman and FTIR spectra of cycled LixMnO2 cathodes showed many distinct bands that can be attributed to both the electrolyte and electrode decomposition products. The thickness of the amorphous porous layer on the LixMnO2 cathode increased during cycling. The surface degradation of LixMnO2 and precipitation of electrolyte decomposition products contributed to the film growth. Improved cycling behavior was observed in cells containing LixTi0.11Mn0.89O2 , yet Raman spectroscopy also showed possible surface degradation. The FTIR spectra of cycled LixMnO2 and LixTi0.11Mn0.89O2 cathodes displayed bands characteristic for LiSO3CF3 and Li2NSO2CF3 , which originate from the reaction of the TFSI anion with traces of water present in the cell.

445

Analysis of macroscopic gunshot residues by Raman spectroscopy to assess the weapon memory effect  

Science Journals Connector (OSTI)

Abstract Gunshot residues (GSR) are valuable evidence which provide the forensic analyst with useful information about a crime scene when proper analytical methods are used. Nowadays, the method of choice for analyzing GSR is scanning electron microscopy coupled with energy dispersive X-ray analysis (SEM/EDX). However, SEM/EDX presents limitations when the GSR identification of “non-toxic” ammunition types is performed. To overcome this drawback, Raman spectroscopy has been recently proposed as a complementary technique to SEM/EDX. However, for the time being, it can only be used in a limited number of casework (e.g. examining the macroscopic GSR produced at short distance over victim's clothes) and further research to know when this technique could support SEM–EDX results is required. In the present work, the memory effect of the weapon, which plays an important role to link the GSR found and the ammunition fired, is studied. Twenty shots were fired at close distance (?30 cm) at paper targets using the same weapon with two different types of ammunition. The first, third, ninth, and twentieth shots were fired with the first ammunition and the shots among them using the second ammunition. The macroscopic GSR produced by the first ammunition were analyzed using Raman spectroscopy. First, the spectra obtained were visually differentiated by taking into account the band at about 1342 cm?1. This first approach shown that in the first shot were no GSR particles from the second ammunition, but 1.5–7.5% of analyzed particles corresponded to the second ammunition in the third, ninth, and twentieth shots. Additionally, the same differentiation was then performed by discriminant analysis using the spectral range from 1800 to 800 cm?1. Although using this second approach only one GSR was identified as the second ammunition, was remarkable that after the shots with different ammunition the GSR obtained shows greater variability. The results obtained suggest that the memory effect of the weapon has not a significant influence when the organic analysis of macroscopic GSR on targets by Raman spectroscopy is performed.

María López-López; Juan Jose Delgado; Carmen García-Ruiz

2013-01-01T23:59:59.000Z

446

Storage and Manipulation of Light Using a Raman Gradient Echo Process  

E-Print Network (OSTI)

The Gradient Echo Memory (GEM) scheme has potential to be a suitable protocol for storage and retrieval of optical quantum information. In this paper, we review the properties of the $\\Lambda$-GEM method that stores information in the ground states of three-level atomic ensembles via Raman coupling. The scheme is versatile in that it can store and re-sequence multiple pulses of light. To date, this scheme has been implemented using warm rubidium gas cells. There are different phenomena that can influence the performance of these atomic systems. We investigate the impact of atomic motion and four-wave mixing and present experiments that show how parasitic four-wave mixing can be mitigated. We also use the memory to demonstrate preservation of pulse shape and the backward retrieval of pulses.

Hosseini, M; Campbell, G T; Lam, P K; Buchler, B C

2012-01-01T23:59:59.000Z

447

Raman spectra of bilayer graphene covered with Poly(methyl methacrylate) thin film  

SciTech Connect

The Raman spectra of bilayer graphene covered with poly(methyl methacrylate) (PMMA) were investigated. Both the G and 2D peaks of PMMA-coated graphene were stiff and broad compared with those of uncovered graphene. This could be attributed to the residual strain induced by high-temperature baking during fabrication of the nanodevice. Furthermore, the two 2D peaks stiffened and broadened with increasing laser power, which is just the reverse to uncovered graphene. The stiffness is likely caused by graphene compression induced by the circular bubble of the thin PMMA film generated by laser irradiation. Our findings may contribute to the application of PMMA in the strain engineering of graphene nanodevices.

Xia Minggang [MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, School of Science, Xi'an Jiaotong University, 710049 (China); Center on Experimental Physics, School of Science, Xi'an Jiaotong University, 710049 (China); Su Zhidan; Zhang Shengli [MOE Key Laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter, School of Science, Xi'an Jiaotong University, 710049 (China); Department of Applied Physics, School of Science, Xi'an Jiaotong University, 710049 (China)

2012-09-15T23:59:59.000Z

448

Subpicosecond time-resolved Raman studies of nonequilibrium excitations in wurtzite GaN  

SciTech Connect

Non-equilibrium electron distributions as well as phonon dynamics in wurtzite GaN have been measured by subpicosecond time-resolved Raman spectroscopy. The experimental results have demonstrated that for electron densities n {ge} 5 {times} 10{sup 17} cm{sup {minus}3}, the non-equilibrium electron distributions in wurtzite GaN can be very well described by Fermi-Dirac distribution functions with the temperature of electrons substantially higher than that of the lattice. The population relaxation time of longitudinal optical phonons was directly measured to be {tau} {approx_equal} 5 {+-} 1 ps at T = 25 K. The experimental results on the temperature dependence of the lifetime of longitudinal optical phonons suggest that the primary decay channels for these phonons are the decay into (1) one transverse optical phonon and one high energy, longitudinal or transverse acoustical phonons; and (2) one transverse optical phonon and one E{sub 2} phonon.

Tsen, K.T.; Ferry, D.K. [Arizona State Univ., Tempe, AZ (United States). Dept. of Physics and Astronomy; Joshi, R.P. [Old Dominion Univ., Norfolk, VA (United States). Dept. of Electrical Engineering; Botchkarev, A.; Sverdlov, B.; Salvador, A.; Morkoc, H. [Univ. of Illinois, Urbana, IL (United States). Coordinated Science Lab.

1997-12-31T23:59:59.000Z

449

Coherent anti-Stokes Raman scattering of laser shock compressed ?-quartz  

Science Journals Connector (OSTI)

We have developed the capability to perform in situ coherent anti-Stokes Raman scattering (CARS) spectroscopy on materials that are dynamically compressed using the Janus laser at Lawrence Livermore National Laboratory. We measured the CARS spectrum of ?-quartz that was shocked above the Hugoniot elastic limit along the c-axis to 19.0 GPa. These data show that the Si-O-Si angle which is natively 144° becomes a distribution of angles ranging from 139° to 146°. The data also observe a significant increase in the broad peak above 600 cm-1 that is attributed to defects in amorphous silica. Previous studies have shown these features in shock recovered ?-quartz samples that have undergone varying amounts of amorphization and these data show strong evidence of amorphization of quartz at a pressure below that of the amorphization observed in the shock-recovered samples.

Cindy Bolme; G. W. Collins

2012-01-01T23:59:59.000Z

450

Final Technical Report "Study of Efficiency of Raman Backscattering Amplification in Plasma"  

SciTech Connect

General : Our major scientific achievements in Raman Backscattering (RBS) amplification and compression of short laser pulses in plasma. The laser system based on RBS steps in where the current technology of chirped pulse amplification (CPA) (extremely successful in developing ultra-short and ultra-intense laser pulses in last 2 decades) becomes difficult and very expensive to apply. Good base for such RBS laser was created by our recent experiments, which were supported by GPS grants. The main objective of the present grant was: improvement efficiency of energy transfer from pump to seed. The results surpassed our expectations; we improved the efficiency of energy transfer from pump to seed by a factor of 6 compared to the best of our previous results and amplified seed pulse compressed down to about 50 fsec.

Suckewer, Szymon

2014-03-31T23:59:59.000Z

451

The coupling of stimulated Raman and Brillouin scattering in a plasma  

SciTech Connect

The observation of an anti-Stokes satellite in the spectrum of light backscattered from a CO{sub 2} laser plasma is reported. Its origin is found to be Thomson scattering of the incident light from a counterpropagating mode-coupled plasma wave. The parent electron and ion waves in the mode-coupling process were driven by stimulated Raman and Brillouin backscattering. The parent and daughter plasma waves were detected by ruby laser Thomson scattering. A computer simulation modeling the experiment shows further cascading of the Stokes backscattered light to lower frequencies, apparently due to its rescattering by another, higher phase velocity, counterpropagating coupled mode. Comparisons with theoretical predictions are presented. 16 refs., 4 figs.

Umstadter, D.; Mori, W.B.; Joshi, C. (Lawrence Livermore National Lab., CA (USA))

1988-09-19T23:59:59.000Z

452

Reactive ion etching-assisted surface-enhanced Raman scattering measurements on the single nanoparticle level  

SciTech Connect

Single-nanoparticle surface-enhanced Raman scattering (SERS) measurement is of essential importance for both fundamental research and practical applications. In this work, we develop a class of single-particle SERS approaches, i.e., reactive ion etching (RIE)-assisted SERS measurements correlated with scanning electron microscopy (SEM) strategy (RIE/SERS/SEM), enabling precise and high-resolution identification of single gold nanoparticle (AuNP) in facile and reliable manners. By using AuNP-coated silicon wafer and quartz glass slide as models, we further employ the developed RIE/SERS/SEM method for interrogating the relationship between SERS substrates and enhancement factor (EF) on the single particle level. Together with theoretical calculation using an established finite-difference-time-domain (FDTD) method, we demonstrate silicon wafer as superior SERS substrates, facilitating improvement of EF values.

Wang, Si-Yi; Jiang, Xiang-Xu; Wei, Xin-Pan; Lee, Shuit-Tong, E-mail: apannale@suda.edu.cn, E-mail: yaohe@suda.edu.cn; He, Yao, E-mail: apannale@suda.edu.cn, E-mail: yaohe@suda.edu.cn [Institute of Functional Nano and Soft Materials - FUNSOM, Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, and Devices Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, Jiangsu 215123 (China); Xu, Ting-Ting [Institute of Functional Nano and Soft Materials - FUNSOM, Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, and Devices Collaborative Innovation Center of Suzhou Nano Science and Technology, Soochow University, Suzhou, Jiangsu 215123 (China); Center of Super-Diamond and Advanced Films (COSDAF), City University of Hong Kong, Hong Kong, China and Department of Physics and Materials Science, City University of Hong Kong, Hong Kong (China)

2014-06-16T23:59:59.000Z

453

Dynamic cancellation of ac Stark shift for pulsed EIT/Raman optical lattice clocks  

E-Print Network (OSTI)

We propose a combination of Electromagnetically Induced Transparency (EIT)/Raman and pulsed spectroscopy techniques to accurately cancel frequency shifts arising from EIT fields in forbidden optical lattice clock transitions of alkaline earth atoms. Time-separated laser pulses are designed to trap atoms in coherent superpositions while eliminating off-resonance ac Stark contributions at particular laser detunings from the intermediate excited state. The scheme achieves efficient population transfer up to 60% with potential inaccuracy $<$ $10^{-17}$. Cancellation of external light shifts determined by a density matrix approach is confirmed by a complex wave-function formalism, sufficient at the mHz accuracy, under low field strengths or short interaction times.

T. Zanon-Willette; A. D. Ludlow; S. Blatt; M. M. Boyd; E. Arimondo; * Jun Ye

2006-10-13T23:59:59.000Z

454

Surface-plasmon-polariton resonance factors in a classical calculation of surface-enhanced Raman scattering  

Science Journals Connector (OSTI)

The effect of resonant excitation of surface-plasmon polaritons of a general metal substrate on the relatively long-range classical enhancement of the surface-enhanced Raman scattering is considered. It is shown that all the three factors in the classical enhancement arising from the presence of the metal, namely the local electric field at the molecular site at the incident frequency, the electrodynamic renormalization factor for the molecular polarizability, and the propagator for the Stokes scattered field, are modified resonantly. However, their individual impact on the total enhancement differs appreciably, depending strongly on the shape of the metal surface and the distance of the molecule from the surface. As an example, explicit results are given for a molecule adsorbed on a small sphere.

G. S. Agarwal; Sudhanshu S. Jha; J. C. Tsang

1982-02-15T23:59:59.000Z

455

Rabi Waves and Peculiarities of Raman Scattering in Carbon Nanotubes, Produced by High Energy Ion Beam Modification of Diamond Single Crystals  

E-Print Network (OSTI)

QED-model for multichain coupled qubit system, proposed in \\cite{Part1}, was confirmed by Raman scattering studies of carbon zigzag-shaped nanotubes, produced by high energy ion beam modification of natural diamond single crystals. New quantum optics phenomenon - Rabi waves - has been experimentally identified for the first time. Raman spectra in perfect quasi-1D carbon nanotubes are quite different in comparison with well known Raman spectra in 2D carbon nanotubes of larger diameter. They characterized by vibronic mode of Su-Schriffer-Heeger $\\sigma$-polaron lattice and its revival part in frequency representation, which is the consequence of Rabi wave packet formation.

Dmitry Yearchuck; Alla Dovlatova

2011-03-06T23:59:59.000Z

456

Detection of triphenylmethane drugs in fish muscle by surface-enhanced raman spectroscopy coupled with Au-Ag core-shell nanoparticles  

Science Journals Connector (OSTI)

Silver -coated gold bimetallic nanoparticles were synthesized and used as substrates for surface-enhanced Raman spectroscopy (SERS) in detecting prohibited triphenylmethane drugs (including crystal violet and malachite green) in fish muscle. The optical ...

Lu Pei, Yiqun Huang, Chunying Li, Yuanyuan Zhang, Barbara A. Rasco, Keqiang Lai

2014-01-01T23:59:59.000Z

457

High-energy conversion efficiency of transient stimulated Raman scattering in methane pumped by the fundamental of a femtosecond Ti:sapphire laser  

Science Journals Connector (OSTI)

We studied stimulated Raman scattering in pressurized methane in the highly transient regime pumped by 140-fs 0.7-mJ pulses from a Ti:sapphire (Ti:S) laser tuned at 750 nm....

Koprinkov, I G; Suda, Akira; Wang, Pengqian; Midorikawa, Katsumi

1999-01-01T23:59:59.000Z

458

Effects of Topological Defects and Diatom Vacancies on Characteristic Vibration Modes and Raman Intensities of Zigzag Single-Walled Carbon Nanotubes  

Science Journals Connector (OSTI)

Wissam A. Saidi * ... Saidi, W. A.; Norman, P.Probing Single-Walled Carbon Nanotube Defect Chemistry Using Resonance Raman Spectroscopy Carbon 2014, 67, 17– 26 ... Saidi, Wissam A.; Norman, Patrick ...

Wissam A. Saidi

2013-11-26T23:59:59.000Z

459

Combination of Lidar Elevations, Bathymetric Data, and Urban Infrastructure in a Sub-Grid Model for Predicting Inundation in New York City during Hurricane Sandy  

E-Print Network (OSTI)

We present the geospatial methods in conjunction with results of a newly developed storm surge and sub-grid inundation model which was applied in New York City during Hurricane Sandy in 2012. Sub-grid modeling takes a novel approach for partial wetting and drying within grid cells, eschewing the conventional hydrodynamic modeling method by nesting a sub-grid containing high-resolution lidar topography and fine scale bathymetry within each computational grid cell. In doing so, the sub-grid modeling method is heavily dependent on building and street configuration provided by the DEM. The results of spatial comparisons between the sub-grid model and FEMA's maximum inundation extents in New York City yielded an unparalleled absolute mean distance difference of 38m and an average of 75% areal spatial match. An in-depth error analysis reveals that the modeled extent contour is well correlated with the FEMA extent contour in most areas, except in several distinct areas where differences in special features cause sig...

Loftis, Jon Derek; Hamilton, Stuart E; Forrest, David R

2014-01-01T23:59:59.000Z

460

Thin and thick cloud top height retrieval algorithm with the Infrared Camera and LIDAR of the JEM-EUSO Space Mission  

E-Print Network (OSTI)

The origin of cosmic rays have remained a mistery for more than a century. JEM-EUSO is a pioneer space-based telescope that will be located at the International Space Station (ISS) and its aim is to detect Ultra High Energy Cosmic Rays (UHECR) and Extremely High Energy Cosmic Rays (EHECR) by observing the atmosphere. Unlike ground-based telescopes, JEM-EUSO will observe from upwards, and therefore, for a properly UHECR reconstruction under cloudy conditions, a key element of JEM-EUSO is an Atmospheric Monitoring System (AMS). This AMS consists of a space qualified bi-spectral Infrared Camera, that will provide the cloud coverage and cloud top height in the JEM-EUSO Field of View (FoV) and a LIDAR, that will measure the atmospheric optical depth in the direction it has been shot. In this paper we will explain the effects of clouds for the determination of the UHECR arrival direction. Moreover, since the cloud top height retrieval is crucial to analyze the UHECR and EHECR events under cloudy conditions, the ret...

Sáez-Cano, G; del Peral, L; Neronov, A; Wada, S; Frías, M D Rodríguez

2015-01-01T23:59:59.000Z

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461

Doubly resonant Raman electron paramagnetic transitions of Cr{sup 3+} in ruby (Al{sub 2}O{sub 3}:Cr{sup 3+}).  

SciTech Connect

We report the Raman electron paramagnetic resonance (EPR) of Cr{sup 3+} in ruby (Al{sub 2}O{sub 3}:Cr{sup 3+}) in the {sup 4}A{sub 2} (ground) and E{sup -} (excited) states of its well-known R{sub 1} emission line. Using tunable dye laser excitation within the range of the Zeeman components of R{sub 1}, we observe highly selective doubly resonant enhancements of the Raman EPR lines. The double resonances confirm the assignments of the Raman EPR lines, and they underscore the simultaneous occurrence of both 'in resonance' and 'out resonance' as visualized in the Kramers-Heisenberg quantum-mechanical picture of inelastic light scattering. The g factors of the {sup 4}A{sub 2} and E{sup -} states are consistent with the observed magnetic field dependence of the Raman EPR shifts. Through the interplay of Raman effect and the sharp Zeeman components of R{sub 1}, the results provide clear insights into the underlying microscopic mechanism of these resonant Raman EPR spectra of ruby.

Lu, X.; Venugopalan, S.; Kim, H.; Grimsditch, M.; Rodriguez, S.; Ramdas, A. K.; Materials Science Division; Purdue Univ.; State Univ. of New York at Binghamton; Sogang Univ.

2009-06-01T23:59:59.000Z

462

Raman spectra and magnetization of all-ferromagnetic superlattices grown on (110) oriented SrTiO{sub 3}  

SciTech Connect

Superlattices consist of two ferromagnets La{sub 0.7}Sr{sub 0.3}MnO{sub 3} (LSMO) and SrRuO{sub 3} (SRO) were grown in (110)-orientation on SrTiO{sub 3} (STO) substrates. The x-ray diffraction and Raman spectra of these superlattices show the presence of in-plane compressive strain and orthorhombic structure of less than 4 u.c. thick LSMO spacer, respectively. Magnetic measurements reveal several features including reduced magnetization, enhanced coercivity, antiferromagnetic coupling, and switching from antiferromagnetic to ferromagnetic coupling with magnetic field orientations. These magnetic properties are explained by the observed orthorhombic structure of spacer LSMO in Raman scattering which occurs due to the modification in the stereochemistry of Mn at the interfaces of SRO and LSMO.

Behera, B. C.; Ravindra, A. V.; Padhan, P. [Department of Physics, Indian Institute of Technology Madras, Chennai 600036 (India); Prellier, W. [Laboratoire CRISMAT, CNRS UMR 6508, ENSICAEN, 6 Bd du Marehal Juin, F-14050 Caen Cedex (France)

2014-03-03T23:59:59.000Z

463

Graphene-based textured surface by pulsed laser deposition as a robust platform for surface enhanced Raman scattering applications  

SciTech Connect

We have developed a surface enhanced Raman scattering (SERS)-active substrate based on gold nanoparticles-decorated few-layer (fl) graphene grown by pulsed laser deposition. Diamond-Like Carbon film has been converted to fl-graphene after thermal annealing at low temperature. The formation of fl-graphene was confirmed by Raman spectroscopy, and surface morphology was highlighted by scanning electron microscopy. We found that textured fl-graphene film with nanoscale roughness was highly beneficial for SERS detection. Rhodamine 6G and p-aminothiophenol proposed as test molecules were detected with high sensitivity. The detection at low concentration of deltamethrin, an active molecule of a commercial pesticide was further demonstrated.

Tite, T.; Donnet, C.; Loir, A.-S.; Reynaud, S.; Michalon, J.-Y.; Vocanson, F.; Garrelie, F., E-mail: florence.garrelie@univ-st-etienne.fr [Université de Lyon, F-42023 Saint-Etienne (France); CNRS, UMR 5516, Laboratoire Hubert Curien, F-42000 Saint-Etienne (France); and Université de Saint-Etienne, Jean Monnet, F-42000 Saint-Etienne (France)

2014-01-27T23:59:59.000Z

464

In situ Raman monitoring of He{sup 2+} irradiation induced damage in a UO{sub 2} ceramic  

SciTech Connect

The in situ Raman probing of a UO{sub 2} ceramic in [Ar/H{sub 2}, 95/5] gas atmosphere followed by exposure to He{sup 2+} ionic irradiation coming from a cyclotron accelerator was implemented. It was observed that the growth of Raman defect bands exhibits a unique kinetic nicely modelized by a simple direct impact model, and with an annealing rate constant of 5.6 × 10{sup ?4} ± 4 × 10{sup ?5} s{sup ?1} for an ionic flow of 50 nA and an ions-beam induced sample heating of 170 ± 10 °C. Also, it was observed that the Ar plasma induced by the ions-beam is a sensitive probe of the presence of the ions-beam.

Guimbretière, G.; Canizarès, A.; Duval, F.; Raimboux, N.; Omnée, R.; Ammar, M. R.; Simon, P. [CNRS/UPR3079 CEMHTI, 45071 Orléans Cedex 2 et Université d'Orléans, 45067 Orléans Cedex 2 (France)] [CNRS/UPR3079 CEMHTI, 45071 Orléans Cedex 2 et Université d'Orléans, 45067 Orléans Cedex 2 (France); Desgranges, L. [CEA/DEN/DEC Bat 352 Cadarache, 13108 Saint Paul lez Durance (France)] [CEA/DEN/DEC Bat 352 Cadarache, 13108 Saint Paul lez Durance (France); Caraballo, R.; Jégou, C. [CEA/DTCD/SECM/LMPA, Marcoule 30207 Bagnols Sur Ceze (France)] [CEA/DTCD/SECM/LMPA, Marcoule 30207 Bagnols Sur Ceze (France)

2013-07-22T23:59:59.000Z

465

Structural Properties of Eu-Doped GaN Investigated by Raman Spectroscopy  

SciTech Connect

Rare-earth (RE) impurities doped GaN are highly promising candidates for light emitting device applications due to their efficient electroluminescence properties at room temperature. Among those, Eu doped GaN has been identified as an excellent material for the red spectral region due to its strong emission at 620 nm. As a transition internal to the Eu doping atom (4f-4f), light emission originates in a much smaller complex than the more flexibly controllable quantum structures of wells, wires, and dots. This is thought to make the center less susceptible to structural defects and in particular radiation damage in the lattice host. Nevertheless, the lattice host is crucial for providing the excitation in from of free electrons and holes. In this respect, the actual lattice site Eu occupies in the host lattice, i.e. in GaN, is important. A large fraction of Eu atoms are typically inactive which must be attributed to their lattice site and local environment. GaN films implanted with Eu to concentrations of {approx}10{sup 18} cm{sup -3} were subjected to a highly directed beam of 500 keV He{sup +} at a dose of 5 x 10{sup 14} cm{sup -2}. By means of a shadow mask, irradiated and unexposed regions lie very close to each other on the same sample. We used optical and structural analysis to identify the exerted radiation damage. At the full radiation dose, photoluminescence intensity has decayed to {approx}0.01 of its initial value. From the dose dependence of the radiation decay we previously concluded, that this decay is in part due to the destruction of radiative Eu sites [J.W. Tringe, unpublished (2006)]. Along the transition from virgin to irradiated material we analyze the accumulated damage in terms of surface morphology (atomic force microscopy), crystallinity (x-ray diffraction), and phonon dispersion using micro-Raman spectroscopy. In addition to the well-studied E{sub 2}(high) mode, two new vibrational modes at 659 cm{sup -1} and 201 cm{sup -1} were observed in the Eu implanted and annealed sample, prior to He{sup +} irradiation. These modes are either remnants of the implantation damage or related to the Eu impurity. As such they can be indicative of the actual lattice site the Eu atom resides on. After irradiation, broad Raman modes at 300 cm-1 are being observed. This band indicates disorder activated Raman scattering (DARS) due to the radiation damage. An additional narrow mode appears at 672 cm{sup -1}, which can possibly be due to a nitrogen vacancy related vibrational mode. The continuous transition from irradiated to un-irradiated sample allows the direct evolution of radiation damage and its coordinated effects in structural, optical and vibrational properties. By its systematic correlation we anticipate to be able to elucidate the Eu lattice interaction and the processes of radiation damage.

Senawiratne, J; Xia, Y; Detchprohm, T; Tringe, J W; Stevens, C G; Wetzel, C

2006-06-20T23:59:59.000Z

466

Stimulated Raman scattering of beat wave of two counter-propagating X-mode lasers in a magnetized plasma  

SciTech Connect

Effects of transverse static magnetic field on stimulated Raman scattering (SRS) of the beat wave excited by two counter-propagating lasers are studied. Two counter-propagating lasers with frequency difference, ?{sub 1}??{sub 2}?2?{sub p}, drive a non resonant space charge beat mode at wave number k{sup ?}{sub 0}?k{sup ?}{sub 1}+k{sup ?}{sub 2} in a plasma, where k{sup ?}{sub 1} and k{sup ?}{sub 2} are wave vectors of lasers having frequencies ?{sub 1} and ?{sub 2}, respectively. The driven beat wave acts as a pump for SRS and excites parametrically a pair of plasma wave (?,k{sup ?}) and side band electromagnetic wave (?{sub 3},k{sup ?}{sub 3}) propagating in the sideward direction in such a way that momentum remains conserved. The growth rate of Raman process is maximum for side scattering at ?{sub s}=?/2 for lower values of applied magnetic field (?1?kG), which can be three fold by applying magnetic field ?5.0?kG. Thus, optimum value of magnetic field can be utilized to achieve maximum electron acceleration in counter propagating geometry of beat wave acceleration by reducing the growth rate of Raman process.

Verma, Kanika; Sajal, Vivek, E-mail: vsajal@rediffmail.com; Varshney, Prateek; Kumar, Ravindra; Sharma, Navneet K. [Department of Physics and Materials Science and Engineering, Jaypee Institute of Information Technology, Noida 201307, UP (India)] [Department of Physics and Materials Science and Engineering, Jaypee Institute of Information Technology, Noida 201307, UP (India)

2014-02-15T23:59:59.000Z

467

Effects of disorder and isotopic substitution in the specific heat and Raman scattering in LuB{sub 12}  

SciTech Connect

Precision measurements of the specific heat and spectral intensity I({omega}) of Raman scattering for Lu{sup N}B{sub 12} single crystal samples with various boron isotopes (N = 10, 11, nat) have been performed at low and intermediate temperatures. A boson peak in the low-frequency part of the I({omega}) spectrum has been observed for the first time for lutetium dodecaboride at liquid nitrogen temperatures. It has been shown that low-temperature anomalies in the specific heat, along with the features of Raman spectra, can be interpreted in terms of the transition to a cageglass state at T* = 50-70 K, which appears when Lu{sup 3+} ions are displaced from the centrosymmetric position in cavities of a rigid covalent boron sublattice towards the randomly located boron vacancies. The concentrations of various two-level systems that correspond to two types of vibrational clusters with correlation lengths of 12-15 and 18-22 A, respectively, have been estimated. The vibrational density of states of LuB{sub 12} has been calculated from Raman spectra in the model of soft atomic potentials. An approach has been proposed to explain the dielectrization of the properties of the YbB{sub 12} compound at T < T*, as well as the features of the formation of magnetic structures in RB{sub 12} antiferromagnets (R = Tb, Dy, Ho, Er, Tm) and the suppression of superconductivity in LuB{sub 12}.

Sluchanko, N. E., E-mail: nes@lt.gpi.ru; Azarevich, A. N.; Bogach, A. V.; Vlasov, I. I.; Glushkov, V. V.; Demishev, S. V. [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation); Maksimov, A. A.; Tartakovskii, I. I.; Filatov, E. V. [Russian Academy of Sciences, Institute of Solid State Physics (Russian Federation); Flachbart, K.; Gabani, S. [Slovak Academy of Sciences, Institute of Experimental Physics (Slovakia); Filippov, V. B.; Shitsevalova, N. Yu. [National Academy of Sciences of Ukraine, Institute of Problems of Materials Science (Ukraine); Moshchalkov, V. V. [Katholieke Universiteit Leuven, Institute of Nanoscale Physics and Chemistry (Belgium)

2011-09-15T23:59:59.000Z

468

Investigation of metal dusting mechanism in Fe-base alloys using Raman spectroscopy, x-ray diffraction, and electron microscopy.  

SciTech Connect

The metal-dusting phenomenon, which is a metal loss process that occurs in hot reactive gases, was investigated in iron and certain iron-base alloys by Raman scattering, X-ray diffraction (XRD), and scanning-electron microscopy (SEM). Coke from metal dusting exhibits six Raman bands at 1330(D band), 1580(G band), 1617, 2685, 3920, and 3235 cm-1. The bandwidths and the relative intensities of the 1330 and 1580 cm-1 bands are related to the crystallinity and defect structure of the coke. Both Raman and XRD analyses suggest that the metal-dusting process influences the catalytic crystallization of carbon. A new mechanism of metal dusting is, therefore, proposed, based on the premise that coke cannot crystallize well by deposition from carburizing gases at low temperature without catalytic activation because of its strong C-C bonds and high melting temperature. Cementite or iron participates in the coke-crystallizing process in a manner that tends to improve the crystallinity of the coke. At the same time, fine iron or cementite particles are liberated from the pure metal or alloys.

Zeng, Z.; Natesan, K.; Maroni, V. A.

2002-08-01T23:59:59.000Z

469

ARM - Facility News Article  

NLE Websites -- All DOE Office Websites (Extended Search)

Raman Lidar Refurbishment and Upgrade Completed Raman Lidar Refurbishment and Upgrade Completed Bookmark and Share During the past several years, the sensitivity of the 8-year old Raman lidar at the ARM Climate Research Facility Southern Great Plains (SGP) site has decreased between a factor of 3-4, resulting in a lower maximum altitude and increased random error in the geophysical properties (such as water vapor mixing ration and aerosol extinction profiles) derived from lidar. In September 2004, a ten-month effort to refurbish and upgrade the aging lidar was completed, as ARM scientists visited the site to align the instrument's newly-refurbished receiving telescope, install new interference filters, and optimize signal levels. Replacing the telescope and interference filters returned the lidar's sensitivity back to its

470

ARM - Instrument - rl  

NLE Websites -- All DOE Office Websites (Extended Search)

govInstrumentsrl govInstrumentsrl Documentation RL : Handbook RL : Instrument Mentor Monthly Summary (IMMS) reports RL : Data Quality Assessment (DQA) reports 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 Instrument : Raman Lidar (RL) Beneficiary of Recovery Act funding. Instrument Categories Aerosols, Atmospheric Profiling Picture of the Raman Lidar (RL) Picture of the Raman Lidar (RL) General Overview The Raman Lidar (RL) is an active, ground-based laser remote sensing instrument that measures vertical profiles of water-vapor mixing ratio and several cloud- and aerosol-related quantities. Lidar (light detection and ranging) is the optical analog of radar, using pulses of laser radiation to probe the atmosphere. This system is fully computer automated, and will run

471

Structure disorder degree of polysilicon thin films grown by different processing: Constant C from Raman spectroscopy  

SciTech Connect

Flat, low-stress, boron-doped polysilicon thin films were prepared on single crystalline silicon substrates by low pressure chemical vapor deposition. It was found that the polysilicon films with different deposition processing have different microstructure properties. The confinement effect, tensile stresses, defects, and the Fano effect all have a great influence on the line shape of Raman scattering peak. But the effect results are different. The microstructure and the surface layer are two important mechanisms dominating the internal stress in three types of polysilicon thin films. For low-stress polysilicon thin film, the tensile stresses are mainly due to the change of microstructure after thermal annealing. But the tensile stresses in flat polysilicon thin film are induced by the silicon carbide layer at surface. After the thin film doped with boron atoms, the phenomenon of the tensile stresses increasing can be explained by the change of microstructure and the increase in the content of silicon carbide. We also investigated the disorder degree states for three polysilicon thin films by analyzing a constant C. It was found that the disorder degree of low-stress polysilicon thin film larger than that of flat and boron-doped polysilicon thin films due to the phase transformation after annealing. After the flat polysilicon thin film doped with boron atoms, there is no obvious change in the disorder degree and the disorder degree in some regions even decreases.

Wang, Quan, E-mail: wangq@mail.ujs.edu.cn [School of mechanical engineering, Jiangsu University, Zhenjiang 212013 (China); State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Zhang, Yanmin; Hu, Ran; Ren, Naifei [School of mechanical engineering, Jiangsu University, Zhenjiang 212013 (China); Ge, Daohan [School of mechanical engineering, Jiangsu University, Zhenjiang 212013 (China); State Key Laboratory of Transducer Technology, Chinese Academy of Sciences, Shanghai 200050 (China)

2013-11-14T23:59:59.000Z

472

Micro-Raman spectroscopy of fluid inclusions in a hopper crystal in halite  

SciTech Connect

Raman microscopy has been used successfully to analyze for dissolved sulfate in fluid inclusions in naturally occurring halite. Hopper crystals are crystals of halite (NaCl) whose structure is produced by crystal growth at the surface of a brine reservoir. Brine is trapped by defects in the growing crystal faces as microscopic fluid inclusions. In this study the hopper crystal was characterized by obtaining a profile of the sulfate (SO/sub 4//sup 2 -/) concentrations in brine inclusions in the bands formed in the hopper crystal structure. In addition, the same sample contained large areas of clear recrystallized halite in which fluid inclusions are not as abundant as those in hopper crystals but are several orders of magnitude larger (frequently several mm on an edge). These larger inclusions were also analyzed for their sulfate content. The sample for this study came from a thick halite unit in the Salado Formation (Permian age) in the Delaware Basin, southeastern New Mexico. The Waste Isolation Pilot Plant (WIPP) is located at a depth of approximately 2150 feet from the surface.

Higgins, K.L.; Stein, C.L.

1986-01-01T23:59:59.000Z

473

Single-photon emission via Raman scattering from the levels with partially resolved hyperfine structure  

E-Print Network (OSTI)

The probability of emission of a single photon via Raman scattering of laser pulse on the three-level $\\Lambda$ - type atom in microcavity is studied. The duration of the pulse is considered to be short enough, so that the hyperfine structure of the upper level remains totally unresolved, while that of the lower level is totally resolved. The coherent laser pulse is assumed to be in resonance with the transition between one hyperfine structure component of the lower atomic level and all hyperfine structure components of the upper level, while the quantized cavity field is assumed to be in resonance with the transition between the other hyperfine structure component of the lower level and all components of the upper one. The dependence of the photon emission probability on the mutual orientation of polarization vectors of the cavity mode and of the coherent laser pulse is analyzed. Particularly, the case is investigated, when the total electronic angular momentum of the lower atomic level equals 1/2, which is true for the ground states of alkali atoms employed in the experiments on deterministic single photon emission. It is shown, that in this case the probability of photon emission equals zero for collinear polarizations of the photon and of the laser pulse, and the probability obtains its maximum value, when the angle between their polarizations equals 60 degrees.

V. A. Reshetov; I. V. Yevseyev

2009-11-24T23:59:59.000Z

474

Raman spectroscopic measurement of oxidation in supercritical water. 2: Conversion of isopropyl alcohol to acetone  

SciTech Connect

The oxidation of isopropyl alcohol in supercritical water has been investigated using Raman spectroscopy. Results for species concentration as a function of residence-time are presented for temperatures ranging from 400 to 480 C at constant pressure, 24.4 {+-} 0.3 MPa, and constant equivalence ratio, 0.88 {+-} 0.0. Acetone has been identified as the principal intermediate formed and subsequently destroyed, during the oxidation process. By assuming first-order kinetics for the destruction of both isopropyl alcohol and acetone, effective first-order rate constants have been determined from fits of the experimental data. Assuming Arrhenius behavior, the fits yield rate constants for isopropyl alcohol, k{sub eff,ipa} = 3.255 {times} 10{sup 22}(s{sup {minus}1}) exp [{minus}301.1 (kJ/mol)/RT], and for acetone, k{sub eff,ace} = 1.948 {times} 10{sup 10}(s{sup {minus}1}) exp[{minus}137.7(kJ/mol)/RT]. These results indicate that for temperatures greater than 425 C, the destruction of isopropyl alcohol proceeds faster than that of acetone.

Hunter, T.B.; Rice, S.F.; Hanush, R.G. [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility] [Sandia National Labs., Livermore, CA (United States). Combustion Research Facility

1996-11-01T23:59:59.000Z

475

Reversible oxidation and rereduction of magnesium phthalocyanine electrodes. Electrochemical behavior and in situ Raman spectroscopy  

SciTech Connect

Reversible oxidation and rereduction of magnesium phthalocyanine (MgPc) thin films (1000-2000 A thick) on gold electrodes have been observed in the potential range from 0.0 to 0.9 V vs. SCE in various electrolytes, including aqueous NaCl, NaNO/sub 3/, NaClO/sub 4/, and potassium hydrogen phthalate (KHP). In situ Raman spectra recorded during oxidation and rereduction show spectral changes in the 400-1800-cm/sup -1/ range that can be related to the vibrational modes of ring structures in MgPc, hence the oxidation seems to occur in the ligand. The spectroscopic results unambiguously demonstrate the movement of anions into and out of the electrode during oxidation and rereduction processes. Both cyclic voltammetry and chronocoulometry showed that smaller anions allow full oxidation at rapid rates, whereas larger ones inhibit the oxidation, at least with respect to rate. Auger electron spectrometry showed that anions appear to be homogeneously distributed in partially oxidized films.

Kahl, J.L.; Faulkner, L.R.; Dwarakanath, K.; Tachikawa, H.

1986-09-03T23:59:59.000Z

476

1  

NLE Websites -- All DOE Office Websites (Extended Search)

Cirrus Extinction and Lidar Ratio Derived from Raman 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 extinction are important parameters for radiative flux and heating rate calculations. The extinction-to-backscatter ratio (also called lidar ratio) provides information on the transmission and reflection properties of cirrus clouds and also on the

477

Gaussian-function-based deconvolution method to determine the penetration ability of petrolatum oil into in vivo human skin using confocal Raman microscopy  

Science Journals Connector (OSTI)

Human skin pre-treated with petrolatum was analyzed in vivo using confocal Raman microscopy in order to determine the penetration depth of the oil into the skin. The broad Raman peak (2820–3030?cm?1) measured in vivo on human skin in the high wavenumber region exhibits two prominent main Raman peaks at 2880?cm?1 and 2935?cm?1 that originated from cutaneous lipids and keratin and two main peak shoulders at 2850?cm?1 and 2980?cm?1 that originated from lipids and keratin, respectively. Topical application of petrolatum oil onto the skin gives rise to an increase of the intensity of the broad lipid–keratin Raman peak (2820–3030?cm?1). Herewith, not only the intensity of the lipid part but also of the keratin part is increased, making the normalization to keratin and the determination of the petrolatum penetration profile erroneous. To solve this problem, the Gaussian-function-based deconvolution method is introduced in analyzing the Raman spectrum of the lipid–keratin peak and the least square method is applied for analyzing the petrolatum penetration profile. Results obtained in vivo show that the petrolatum oil does not penetrate deeper than 10?µm into intact human skin.

Chun-Sik Choe; Jürgen Lademann; Maxim E Darvin

2014-01-01T23:59:59.000Z

478

Characterization of lithium electrode surface in lithium secondary batteries by in situ Raman spectroscopic methods. Final report, 1 September 1989-31 December 1992  

SciTech Connect

Surface layers on lithium electrodes formed in several solvents including dimethyl carbonate (DMC), diethyl carbonate (DEC), polyethylene glycol 400 dimethyl ether (PEG400DME), and propylene carbonate (PC) have been studied by Raman spectroscopy. Both DMC and DEC were used singly, and also mixed with either methyl acetate or methyl formate. The Raman spectra showed that passive films formed on the Li surface in different solvents may have different chemical structures, which changed during the charging and discharging processes. A solid film of fullerene C6O, which could be used as a cathode in Li rechargeable batteries, was examined in the PEG400DME solution by both electrochemical and Raman spectroscopy. Cyclic voltammograms (CVs) showed five redox peaks which suggested the formation of C6O(-), C6O(2-), C6O(3-), C6O(4-), and C6O(5-). Raman spectra obtained from thin C6O film indicated that the thin fulleride film dissolved in the PEG400DME/LiClO(4) solution at negative potentials.... Lithium electrode, Fullerenes, Electrochemistry, Raman spectroscopy.

Tachikawa, H.

1993-03-24T23:59:59.000Z

479

Raman Scattering Sensor for Control of the Acid Alkylation Process in Gasoline Production  

SciTech Connect

Gasoline refineries utilize a process called acid alkylation to increase the octane rating of blended gasoline, and this is the single most expensive process in the refinery. For process efficiency and safety reasons, the sulfuric acid can only be used while it is in the concentration range of 98 to 86 %. The conventional technique to monitor the acid concentration is time consuming and is typically conducted only a few times per day. This results in running higher acid concentrations than they would like to ensure that the process proceeds uninterrupted. Maintaining an excessively high acid concentration costs the refineries millions of dollars each year. Using SBIR funding, Process Instruments Inc. has developed an inline sensor for real time monitoring of acid concentrations in gasoline refinery alkylation units. Real time data was then collected over time from the instrument and its responses were matched up with the laboratory analysis. A model was then developed to correlate the laboratory acid values to the Raman signal that is transmitted back to the instrument from the process stream. The instrument was then used to demonstrate that it could create real-time predictions of the acid concentrations. The results from this test showed that the instrument could accurately predict the acid concentrations to within ~0.15% acid strength, and this level of prediction proved to be similar or better then the laboratory analysis. By utilizing a sensor for process monitoring the most economic acid concentrations can be maintained. A single smaller refinery (50,000 barrels/day) estimates that they should save over $120,000/year, with larger refineries saving considerably more.

Uibel, Rory, H.; Smith, Lee M.; Benner, Robert, E.

2006-04-19T23:59:59.000Z

480

Determination of saccharides and ethanol from biomass conversion using Raman spectroscopy: Effects of pretreatment and enzyme composition  

SciTech Connect

This dissertation focuses on the development of facile and rapid quantitative Raman spectroscopy measurements for the determination of conversion products in producing bioethanol from corn stover. Raman spectroscopy was chosen to determine glucose, xylose and ethanol in complex hydrolysis and fermentation matrices. Chapter 1 describes the motives and main goals of this work, and includes an introduction to biomass, commonly used pretreatment methods, hydrolysis and fermentation reactions. The principles of Raman spectroscopy, its advantages and applications related to biomass analysis are also illustrated. Chapter 2 and 3 comprise two published or submitted manuscripts, and the thesis concludes with an appendix. In Chapter 2, a Raman spectroscopic protocol is described to study the efficiency of enzymatic hydrolysis of cellulose by measuring the main product in hydrolysate, glucose. Two commonly utilized pretreatment methods were investigated in order to understand their effect on glucose measurements by Raman spectroscopy. Second, a similar method was set up to determine the concentration of ethanol in fermentation broth. Both of these measurements are challenged by the presence of complex matrices. In Chapter 3, a quantitative comparison of pretreatment protocols and the effect of enzyme composition are studied using systematic methods. A multipeak fitting algorithm was developed to analyze spectra of hydrolysate containing two analytes: glucose and xylose. Chapter 4 concludes with a future perspective of this research area. An appendix describes a convenient, rapid spectrophotometric method developed to measure cadmium in water. This method requires relatively low cost instrumentation and can be used in microgravity, such as space shuttles or the International Space Station. This work was performed under the supervision of Professor Marc Porter while at Iowa State University. Research related to producing biofuel from bio-renewable resources, especially bioethanol from biomass, has grown significantly in the past decade due to the high demand and rising costs of fossil fuels. More than 3 percent of the energy consumption in the U.S. is derived from renewable biomass, mostly through industrial heat and steam production by the pulp and paper industry, and electricity generation from municipal solid waste (MSW) and forest industry residues. The utilization of food-based biomass to make fuels has been widely criticized because it may increase food shortages throughout the world and raise the cost of food. Thus, nonfood-based and plentiful lignocellulosic feedstocks, such as corn stover, perennial grass, bagasse, sorghum, wheat/rice straw, herbaceous and woody crops, have great potential to be new bio-renewable sources for energy production. Given that many varieties of biomass are available, there is need for a rapid, simple, high-throughput method to screen the conversion of many plant varieties. The most suitable species for each geographic region must be determined, as well as the optimal stage of harvest, impacts of environmental conditions (temperature, soil, pH, etc.). Various genetically modified plants should be studied in order to establish the desired biomass in bioethanol production. The main screening challenge, however, is the complexity of plant cell wall structures that make reliable and sensitive analysis difficult. To date, one of the most popular methods to produce lignocellulosic ethanol is to perform enzymatic hydrolysis followed by fermentation of the hydrolysate with yeast. There are several vital needs related to the field of chemistry that have been suggested as primary research foci needed to effectively improve lignocellulosic ethanol production. These topics include overcoming the recalcitrance of cellulosic biomass, the pervasiveness of pretreatment, advanced biological processing and better feedstocks. In this thesis, a novel approach using Raman spectroscopy has been developed to address important issues related to bioethanol generation, which will aid the research aimed to solve the topics m

Shih, Chien-Ju

2010-05-16T23:59:59.000Z

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481

Coherent anti?Stokes Raman spectroscopy study of collisional broadening in the O2–H2O Q branch  

Science Journals Connector (OSTI)

The fundamental isotropic Raman Q branch of oxygen perturbed by collisions with water vapor has been studied at pressures up to 1.5 atm and for temperatures between 446 and 990 K. The spectra have been recorded by using coherent anti?Stokes Raman spectroscopy(CARS) which has been preferred to stimulated Raman spectroscopy(SRS) in order to obtain more signal and higher sensitivity as the mixture has a small percentage of oxygen. The high resolution CARS spectrometer uses a seeded Nd:YAG laser actively stabilized on an external Fabry–Perot interferometer to prevent any frequency drift during the course of the experiment. The line broadening coefficients have been determined for several rotational quantum numbers (up to N=31 at 990 K). The effect of the splitting into triplets at lower pressure and the effect of interferences between neighboring lines at higher pressure have been taken into account. The influence of Dicke narrowing has also been considered and special care has been taken to avoid Stark broadening. The line broadening coefficients have been calculated according to a semiclassical model. The rotational quantum number and temperature dependencies of the experimental line broadening coefficients have also been studied with another approach based on fitting and scaling laws. Among several laws the modified exponential energy gap law (MEG) the statistical power?exponential gap law (SPEG) and the energy corrected sudden law with basis rate constants taken as a hybrid exponential?power law (ECS?EP) have given good results. We have used the fitting and scaling laws to extrapolate in temperature the linewidths at 2000 K.

G. Fanjoux; G. Millot; R. Saint?Loup; R. Chaux; L. Rosenmann

1994-01-01T23:59:59.000Z

482

Enhancement of surface phonon modes in the Raman spectrum of ZnSe nanoparticles on adsorption of 4-mercaptopyridine  

SciTech Connect

By chemically etching a thin film of crystalline ZnSe with acid, we observe a strong Raman enhancement of the surface phonon modes of ZnSe on adsorption of a molecule (4-mercaptopyridine). The surface is composed of oblate hemi-ellipsoids, which has a large surface-to-bulk ratio. The assignment of the observed modes (at 248 and 492 cm{sup ?1}) to a fundamental and first overtone of the surface optical mode is consistent with observations from high-resolution electron energy loss spectroscopy as well as calculations.

Islam, Syed K.; Lombardi, John R. [Department of Chemistry, The City College of New York, New York, New York 10031 (United States)] [Department of Chemistry, The City College of New York, New York, New York 10031 (United States)

2014-02-21T23:59:59.000Z

483

Numerical modeling of quasitransient backward Raman amplification of laser pulses in moderately undercritical plasmas with multicharged ions  

SciTech Connect

It was proposed recently that powerful optical laser pulses could be efficiently compressed through backward Raman amplification in ionized low density solids, in spite of strong damping of the resonant Langmuir wave. It was argued that, even for nonsaturated Landau damping of the Langmuir wave, the energy transfer from the pump laser pulse to the amplified seed laser pulse can nevertheless be highly efficient. This work numerically examines such regimes of strong damping, called quasitransient regimes, within the simplest model that takes into account the major effects. The simulations indicate that compression of powerful optical laser pulses in ionized low density solids indeed can be highly efficient.

Balakin, A. A.; Fraiman, G. M. [Institute of Applied Physics RAS, Nizhnii Novgorod 603950 (Russian Federation); Fisch, N. J. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540 (United States); Malkin, V. M. [Department of Astrophysical Sciences, Princeton University, Princeton, New Jersey 08540 (United States); Toroker, Z. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

2011-10-15T23:59:59.000Z

484

Preparation of Ag{sub 2}S-Graphene nanocomposite from a single source precursor and its surface-enhanced Raman scattering and photoluminescent activity  

SciTech Connect

Ag{sub 2}S-Graphene nanocomposite was prepared via a relatively facile hydrothermal method, using a single-source molecular (silver diethyldithiocarbamate [Ag(DDTC)]) as precursor and graphene sheets as a support material. The composite was characterized by X-ray power diffraction, X-ray photoelectron spectroscopy, Field-emission scanning electron microscope, transmission electron microscopy, Fourier transform infrared, Raman spectra and fluorescence spectroscopy. The experimental results show that the Ag{sub 2}S-Graphene nanocomposite displays surface-enhanced Raman scattering (SERS) activity for graphene oxide and reveals relatively better fluorescence property compared with pure Ag{sub 2}S. Highlights: {yields} Ag{sub 2}S nanoparticles are deposited on graphene sheets via a single source precursor. {yields} Graphene oxide is reduced to graphene in the hydrothermal reaction process. {yields} Ag{sub 2}S-Graphene system displays surface-enhanced Raman scattering activity and relatively better fluorescence property.

Pan Shugang; Liu Xiaoheng, E-mail: xhliu@mail.njust.edu.cn; Wang Xin

2011-11-15T23:59:59.000Z

485

Raman spectroscopy of solutions and interfaces containing nitrogen dioxide, water, and 1,4 dioxane: Evidence for repulsion of surface water by NO{sub 2} gas  

SciTech Connect

The interaction of water, 1,4 dioxane, and gaseous nitrogen dioxide, has been studied as a function of distance measured through the liquid-vapour interface by Raman spectroscopy with a narrow (<0.1 mm) laser beam directed parallel to the interface. The Raman spectra show that water is present at the surface of a dioxane-water mixture when gaseous NO{sub 2} is absent, but is virtually absent from the surface of a dioxane-water mixture when gaseous NO{sub 2} is present. This is consistent with recent theoretical calculations that show NO{sub 2} to be mildly hydrophobic.

Murdachaew, Garold [Institute of Chemistry and the Fritz Haber Research Center for Molecular Dynamics, Hebrew University, Jerusalem 91904 (Israel)] [Institute of Chemistry and the Fritz Haber Research Center for Molecular Dynamics, Hebrew University, Jerusalem 91904 (Israel); Varner, Mychel E.; Veer, Wytze E. van der [Department of Chemistry, University of California, Irvine, California 92697 (United States)] [Department of Chemistry, University of California, Irvine, California 92697 (United States); Gerber, R. Benny [Institute of Chemistry and the Fritz Haber Research Center for Molecular Dynamics, Hebrew University, Jerusalem 91904 (Israel) [Institute of Chemistry and the Fritz Haber Research Center for Molecular Dynamics, Hebrew University, Jerusalem 91904 (Israel); Department of Chemistry, University of California, Irvine, California 92697 (United States); Phillips, Leon F., E-mail: leon.phillips@canterbury.ac.nz [Department of Chemistry, University of California, Irvine, California 92697 (United States); Department of Chemistry, University of Canterbury, Private Bag 4800, Christchurch (New Zealand)

2014-05-14T23:59:59.000Z

486

Experimental demonstration of mode-selective phonon excitation of 6H-SiC by a mid-infrared laser with anti-Stokes Raman scattering spectroscopy  

SciTech Connect

Mode-selective phonon excitation by a mid-infrared laser (MIR-FEL) is demonstrated via anti-Stokes Raman scattering measurements of 6H-silicon carbide (SiC). Irradiation of SiC with MIR-FEL and a Nd-YAG laser at 14 K produced a peak where the Raman shift corresponds to a photon energy of 119 meV (10.4 ?m). This phenomenon is induced by mode-selective phonon excitation through the irradiation of MIR-FEL, whose photon energy corresponds to the photon-absorption of a particular phonon mode.

Yoshida, Kyohei; Hachiya, Kan; Okumura, Kensuke; Mishima, Kenta; Inukai, Motoharu; Torgasin, Konstantin; Omer, Mohamed [Graduate School of Energy Science, Kyoto University, Yoshida-honmachi, Sakyo-ku, Kyoto 606-8501 (Japan)] [Graduate School of Energy Science, Kyoto University, Yoshida-honmachi, Sakyo-ku, Kyoto 606-8501 (Japan); Sonobe, Taro [Kyoto University Research Administration Office, Kyoto University, Yoshida-honmachi, Sakyo-ku, Kyoto 606-8501 (Japan)] [Kyoto University Research Administration Office, Kyoto University, Yoshida-honmachi, Sakyo-ku, Kyoto 606-8501 (Japan); Zen, Heishun; Negm, Hani; Kii, Toshiteru; Masuda, Kai; Ohgaki, Hideaki [Institute of Advanced Energy, Kyoto University, Gokasyo, Uji, Kyoto 611-0011 (Japan)] [Institute of Advanced Energy, Kyoto University, Gokasyo, Uji, Kyoto 611-0011 (Japan)

2013-10-28T23:59:59.000Z

487

Synthesis of silver particles on copper substrates using ethanol-based solution for surface-enhanced Raman spectroscopy  

SciTech Connect

The displacement reaction of AgNO{sub 3} and copper metal is an effective and economical way to fabricate Ag-Cu surface enhanced Raman scattering (SERS) substrates. Aqueous solutions of AgNO{sub 3} are usually used for substrate preparation. In this work, a new method for Ag-Cu SERS substrate preparation is proposed, which uses an ethanol solution rather than an aqueous AgNO{sub 3} solution. Analysis of the surface morphologies of sample substrates by field emission scanning electron microscopy (FESEM) showed that the silver nanoparticles prepared by this new method were more regular than those prepared in the traditional aqueous solution. The SERS spectra of Rhodamine 6G (R6G) adsorbed on these Ag-Cu substrates were then investigated and compared. It was found that the Ag-Cu substrates prepared by this method provide significant improvements in Raman signal sensitivity and large-area uniformity. The enhancement factor of this new substrate is about 330 times higher than that prepared using an aqueous AgNO{sub 3} solution under identical experimental conditions. It was also found that 70% of the original sensitivity of the substrate remains after 15 days of exposure to air.

Chen, Li, E-mail: CL2009@cqu.edu.cn; Zhang, Zuojun; Chen, Gang; Zhou, Hui [Defense Key Disciplines Lab of Novel Micro-nano Devices and System Technology, and Key Laboratory of Optoelectronic Technology and Systems, Chongqing University, Chongqing 400044 (China)] [Defense Key Disciplines Lab of Novel Micro-nano Devices and System Technology, and Key Laboratory of Optoelectronic Technology and Systems, Chongqing University, Chongqing 400044 (China); Lai, Chunhong [Defense Key Disciplines Lab of Novel Micro-nano Devices and System Technology, and Key Laboratory of Optoelectronic Technology and Systems, Chongqing University, Chongqing 400044 (China) [Defense Key Disciplines Lab of Novel Micro-nano Devices and System Technology, and Key Laboratory of Optoelectronic Technology and Systems, Chongqing University, Chongqing 400044 (China); School of Physics and Electronic Information, China West Normal University, NanChong 637002 (China)

2014-03-15T23:59:59.000Z

488

Laser irradiation effects on the CdTe/ZnTe quantum dot structure studied by Raman and AFM spectroscopy  

SciTech Connect

Micro-Raman spectroscopy has been applied to investigate the impact of laser irradiation on semiconducting CdTe/ZnTe quantum dots (QDs) structures. A reference sample (without dots) was also studied for comparison. Both samples were grown by molecular beam epitaxy technique on the p-type GaAs substrate. The Raman spectra have been recorded for different time of a laser exposure and for various laser powers. The spectra for both samples exhibit peak related to the localized longitudinal (LO) ZnTe phonon of a wavenumber equal to 210 cm{sup -1}. For the QD sample, a broad band corresponding to the LO CdTe phonon related to the QD-layer appears at a wavenumber of 160 cm{sup -1}. With increasing time of a laser beam exposure and laser power, the spectra get dominated by tellurium-related peaks appearing at wavenumbers around 120 cm{sup -1} and 140 cm{sup -1}. Simultaneously, the ZnTe surface undergoes rising damage, with the formation of Te aggregates at the pinhole edge as reveal atomic force microscopy observations. Local temperature of irradiated region has been estimated from the anti-Stokes/Stokes ratio of the Te modes intensity and it was found to be close or exceeding ZnTe melting point. Thus, the laser damage can be explained by the ablation process.

Zielony, E.; Placzek-Popko, E.; Henrykowski, A.; Gumienny, Z.; Kamyczek, P.; Jacak, J. [Institute of Physics, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw (Poland); Nowakowski, P.; Karczewski, G. [Institute of Physics, Polish Academy of Sciences, al. Lotnikow 32/46, 02-668 Warsaw (Poland)

2012-09-15T23:59:59.000Z

489

Nonlinear Raman Shift Induced by Exciton-to-Trion Transformation in Suspended Trilayer MoS2  

E-Print Network (OSTI)

Layered two-dimensional (2D) semiconductors such as molybdenum disulfide (MoS2) have recently attracted remarkable attention because of their unique physical properties. Here, we use photoluminescence (PL) and Raman spectroscopy to study the formation of the so- called trions in a synthesized freestanding trilayer MoS2. A trion is a charged quasi-particle formed by adding one electron or hole to a neutral exciton (a bound electron-hole pair). We demonstrate accurate control over the transformation of excitons to trions by tuning the power of the optical pump (laser). Increasing the power of the excitation laser beyond a certain threshold (~ 4 mW) allows modulation of trion-to-exciton PL intensity ratio as well as the spectral linewidth of both trions and excitons. Via a systematic and complementary Raman analysis we disclose a strong coupling between laser induced exciton-to-trion transformation and the characteristic phononic vibrations of MoS2. The onset of such an optical transformation corresponds to the ...

Taghinejad, Hossein; Tarasov, Alexey; Tsai, Meng-Yen; Hosseinnia, Amir H; Campbell, Philip M; Eftekhar, Ali A; Vogel, Eric M; Adibi, Ali

2015-01-01T23:59:59.000Z

490

UV-Raman spectroscopy, X-ray photoelectron spectroscopy, and temperature programmed desorption studies of model and bulk heterogeneous catalysts  

SciTech Connect

X-ray photoelectron spectroscopy (XPS) and Temperature Programmed Desorption (TPD) have been used to investigate the surface structure of model heterogeneous catalysts in ultra-high vacuum (UHV). UV-Raman spectroscopy has been used to probe the structure of bulk model catalysts in ambient and reaction conditions. The structural information obtained through UV-Raman spectroscopy has been correlated with both the UHV surface analysis and reaction results. The present day propylene and ethylene polymerization catalysts (Ziegler-Natta catalysts) are prepared by deposition of TiCl{sub 4} and a Al(Et){sub 3} co-catalyst on a microporous Mg-ethoxide support that is prepared from MgCl{sub 2} and ethanol. A model thin film catalyst is prepared by depositing metallic Mg on a Au foil in a UHV chamber in a background of TiCl{sub 4} in the gas phase. XPS results indicate that the Mg is completely oxidized to MgCl{sub 2} by TiCl{sub 4} resulting in a thin film of MgCl{sub 2}/TiCl{sub x}, where x = 2, 3, and 4. To prepare an active catalyst, the thin film of MgCl{sub 2}/TiCl{sub x} on Au foil is enclosed in a high pressure cell contained within the UHV chamber and exposed to {approx}1 Torr of Al(Et){sub 3}.

Tewell, Craig R.

2002-08-19T23:59:59.000Z

491

Stimulated Raman adiabatic passage from an atomic to a molecular Bose-Einstein condensate P. D. Drummond and K. V. Kheruntsyan  

E-Print Network (OSTI)

to maintain high conversion efficiencies with smaller Rabi frequencies and under experimentally less demanding of the condensates. The result is that the STIRAP process appears feasible at high laser pulse intensities, providedStimulated Raman adiabatic passage from an atomic to a molecular Bose-Einstein condensate P. D

Heinzen, Daniel J.

492

MECHANISM OF THE PHASE CHANGE IN PbK2LiNb5O15: Dielectric, structural, and Raman scattering studies  

E-Print Network (OSTI)

unambiguously that the phase change in this material occurs between P4/mbm and Pba2 space groups, in goodMECHANISM OF THE PHASE CHANGE IN PbK2LiNb5O15: Dielectric, structural, and Raman scattering studies and ferroelectric phases and a complex structural change between them. High and low temperature phases

Boyer, Edmond

493

Second-order Raman spectra of single and multiwalled carbon nanotubes Institut fur Festkorperphysik, Technische Universtat Berlin, Hardenbergstrasse 36, 10623 Berlin, Germany  

E-Print Network (OSTI)

. The excitation-energy dependence of the D and DÃ? modes in single-walled nanotubes is 38 and 90 cm 1 /eSecond-order Raman spectra of single and multiwalled carbon nanotubes C. Thomsen Institut fu of single- walled nanotubes softens by 30 cm 1 over the value of graphite. A comparison of the phonon

Nabben, Reinhard

494

Raman Spectroscopy of Aminated and Ultrafine 1,3,5-Triamino-2,4,6-trinitrobenzene and PBX 9502 as a Function of Pressing Pressure  

Science Journals Connector (OSTI)

The Raman spectra of emulsion aminated, wet aminated, dry aminated, and ultrafine 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) and PBX 9502 explosive powders are measured in a pellet die at pressures from ambient to 180 MPa with a 632.8 nm helium?neon ...

John A. Holy

2008-05-31T23:59:59.000Z

495

Raman spectrum and ESR of Pr0.5Ca0.4Sr0.1MnO3  

NLE Websites -- All DOE Office Websites (Extended Search)

Raman spectrum and ESR of Pr 0.5 Ca 0.4 Sr 0.1 MnO 3 H.-D. Zhou a , G. Li a , F. Liu a , S.-J. Feng a , Y. Liu a , X.-G. Li a, * , J. Fang b a Structure Research Laboratory,...

496

Resonant-Raman intensities and transition energies of the E11 transition in carbon nanotubes * J. Maultzsch,1 S. Reich,2 and C. Thomsen1  

E-Print Network (OSTI)

Resonant-Raman intensities and transition energies of the E11 transition in carbon nanotubes H- troscopy. Radial breathing mode spectra were collected varying the excitation energy in the near-infrared from 1.15 to 1.48 eV. From resonance profiles we obtained the E11 S energies of 11 nanotubes, extending

Nabben, Reinhard

497

Inner-Shell Excitation Spectroscopy of Fused-Ring Aromatic Molecules by Electron Energy Loss and X-ray Raman Techniques  

E-Print Network (OSTI)

Versity, Hamilton, ON, L8S 4M1, Canada, Department of Chemistry, Utrecht UniVersity, 3584 CA Utrecht, The Netherlands, Schlumberger-Doll Research, Ridgefield, Connecticut 06877, Department of Applied Science, Uni that could be applied without modifying the hydrocarbon material. Inelastic X-ray Raman scattering (XRS)2

Hitchcock, Adam P.

498

Microtopographic characterization of ice-wedge polygon landscape in Barrow, Alaska: a digital map of troughs, rims, centers derived from high resolution (0.25 m) LiDAR data  

DOE Data Explorer (OSTI)

The dataset represents microtopographic characterization of the ice-wedge polygon landscape in Barrow, Alaska. Three microtopographic features are delineated using 0.25 m high resolution digital elevation dataset derived from LiDAR. The troughs, rims, and centers are the three categories in this classification scheme. The polygon troughs are the surface expression of the ice-wedges that are in lower elevations than the interior polygon. The elevated shoulders of the polygon interior immediately adjacent to the polygon troughs are the polygon rims for the low center polygons. In case of high center polygons, these features are the topographic highs. In this classification scheme, both topographic highs and rims are considered as polygon rims. The next version of the dataset will include more refined classification scheme including separate classes for rims ad topographic highs. The interior part of the polygon just adjacent to the polygon rims are the polygon centers.

Gangodagamage, Chandana; Wullschleger, Stan

499

Microtopographic characterization of ice-wedge polygon landscape in Barrow, Alaska: a digital map of troughs, rims, centers derived from high resolution (0.25 m) LiDAR data  

SciTech Connect

The dataset represents microtopographic characterization of the ice-wedge polygon landscape in Barrow, Alaska. Three microtopographic features are delineated using 0.25 m high resolution digital elevation dataset derived from LiDAR. The troughs, rims, and centers are the three categories in this classification scheme. The polygon troughs are the surface expression of the ice-wedges that are in lower elevations than the interior polygon. The elevated shoulders of the polygon interior immediately adjacent to the polygon troughs are the polygon rims for the low center polygons. In case of high center polygons, these features are the topographic highs. In this classification scheme, both topographic highs and rims are considered as polygon rims. The next version of the dataset will include more refined classification scheme including separate classes for rims ad topographic highs. The interior part of the polygon just adjacent to the polygon rims are the polygon centers.

Gangodagamage, Chandana; Wullschleger, Stan

2014-07-03T23:59:59.000Z

500

Rabi Wave Packets and Peculiarities of Raman Scattering in Carbon Nanotubes, Produced by High Energy Ion Beam Modification of Diamond Single Crystals  

E-Print Network (OSTI)

QED-model for multichain coupled qubit system, proposed in \\cite{Part1}, was confirmed by Raman scattering studies of quasi-1D carbon zigzag-shaped nanotubes (CZSNTs), produced by high energy ion beam modification of natural diamond single crystals. Multichain coupled qubit system represents itself Su-Schriffer-Heeger $\\sigma$-polaron lattice, formed in CZSNTs plus quantized external electromagnetic (EM) field. New quantum optics phenomenon - Rabi waves, predicted in \\cite{Slepyan_Yerchak} has experimentally been identified for the first time. It is shown, that Raman spectra in quasi-1D CZSNTs are quite different in comparison with well known Raman spectra in 2D those ones. They characterized by semiclassical consideration by the only one vibronic mode of Su-Schriffer-Heeger $\\sigma$-polaron lattice instead of longitudinal and transverse optical phonon $G^+$ and $G^-$modes and the out-of-plane radial breathing mode, which are observed in Raman spectra of 2D single wall nanotubes. It is consequence of 2D - 1D transition in all physical properties of nanotubes. It is shown, that strong electron-photon coupling takes place in CZSNTs by interaction with EM-field and quantum nature of EM-field has to be taken into account. It has been done for the first time in stationary spectroscopy at all. All optical spectra, in particular, Raman spectra are registered by usual stationary measurement technique in nonequilibrium conditions, which are the consequence of Rabi wave packets' formation. It leads in its turn to appearance of additional lines, corresponding to revival part of inversion dependence of joint EM-field + matter system in frequency representation.

Dmitry Yearchuck; Alla Dovlatova

2011-05-26T23:59:59.000Z