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1

Cascades Geothermal Region | Open Energy Information  

Open Energy Info (EERE)

Cascades Geothermal Region Cascades Geothermal Region Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Cascades Geothermal Region Details Areas (21) Power Plants (0) Projects (3) Techniques (5) Map: {{{Name}}} The Cascade Range is part of a vast mountain chain that extends from British Columbia to northern California and has been volcanically active for ~ 40 million years as a result of the convergence of the of the Juan de Fuca and Pacific plates. Two physiographic sub-provinces make up the Cascade Range; the Western Cascades and the High Cascades on the east. Middle Eocene to early Pliocene (40 - 5 million years) thick mafic lava flows, primarily of andesitic composition are associated with ash flows, tuffs, and silicic intrusive bodies and stocks that decrease in age eastward to the High Cascades. Miocene to Holocene volcanic rocks make up

2

Cascades Geothermal Region | Open Energy Information  

Open Energy Info (EERE)

Cascades Geothermal Region Cascades Geothermal Region (Redirected from Cascades) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Cascades Geothermal Region Details Areas (21) Power Plants (0) Projects (3) Techniques (5) Map: {{{Name}}} The Cascade Range is part of a vast mountain chain that extends from British Columbia to northern California and has been volcanically active for ~ 40 million years as a result of the convergence of the of the Juan de Fuca and Pacific plates. Two physiographic sub-provinces make up the Cascade Range; the Western Cascades and the High Cascades on the east. Middle Eocene to early Pliocene (40 - 5 million years) thick mafic lava flows, primarily of andesitic composition are associated with ash flows, tuffs, and silicic intrusive bodies and stocks that decrease in age

3

GEA Heat Exchangers GEA Searle Cooler and Condensing Unit Ranges  

E-Print Network [OSTI]

have high efficiency EC fans as standard across the range. All our commercial unit coolers have whiteUnits GEA Searle Condensing Units are supplied as standard to a high specification with a complete controlGEA Heat Exchangers GEA Searle Cooler and Condensing Unit Ranges Top-level engineering solutions

Frandsen, Søren

4

GEA Geothermal Summit Presentation ? Lauren Boyd | Department...  

Energy Savers [EERE]

Summit Presentation Lauren Boyd GEA Geothermal Summit Presentation Lauren Boyd GEA geothermal energy industry briefing presentation on February 26, 2013 in Washington, D.C....

5

GEA | OpenEI Community  

Open Energy Info (EERE)

GEA GEA Home Kyoung's picture Submitted by Kyoung(155) Contributor 14 October, 2013 - 20:19 Geothermal NEPA Workshop at GRC Categorical Exclusions CX Database EA EIS FONSI GEA GRC GRR NEPA On Tuesday, October 2, the Geothermal Technology Office and the National Renewable Energy Laboratory held a 1/2-day NEPA workshop. The workshop was held at the MGM Grand in Las Vegas, in conjunction with the GEA/GRC Tradeshow and Conference. Three presentations were given, describing the NEPA database and associated analysis that had been conducted in 2013. Files: application/vnd.openxmlformats-officedocument.presentationml.presentation icon 2. NEPA History - Presentation application/vnd.openxmlformats-officedocument.presentationml.presentation icon 3. Categorical Exclusions - Presentation

6

Data Acquisition-Manipulation At Cascades Region (Ingebritsen...  

Open Energy Info (EERE)

Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Data Acquisition-Manipulation At Cascades Region (Ingebritsen & Mariner, 2010) Exploration...

7

GEA Refrigeration Technologies / GEA Refrigeration Germany GmbH Wolfgang Dietrich / Dr. Ole Fredrich  

E-Print Network [OSTI]

GEA Refrigeration Technologies / GEA Refrigeration Germany GmbH Wolfgang Dietrich / Dr. Ole Technologies3 Achema 2012 // heat pumps using ammonia Industrial demand on heat in Germany Heatdemandin

Oak Ridge National Laboratory

8

GEA Development Phases | Open Energy Information  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » GEA Development Phases Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home GEA Development Phases The information for this page was taken directly from Geothermal Reporting Terms and Definitions: A Guide to Reporting Resource Development Progress and Results to the Geothermal Energy Association (GEA, November 2010) Gea.jpg The Geothermal Energy Association's (GEA) Geothermal Reporting Terms and Definitions are a guideline for geothermal developers to use when submitting geothermal resource development information to GEA for public dissemination in its annual US Geothermal Power Production and Development

9

Field Mapping At Cascades Region (Ingebritsen & Mariner, 2010) | Open  

Open Energy Info (EERE)

source source History View New Pages Recent Changes All Special Pages Semantic Search/Querying Get Involved Help Apps Datasets Community Login | Sign Up Search Page Edit History Facebook icon Twitter icon » Field Mapping At Cascades Region (Ingebritsen & Mariner, 2010) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Field Mapping At Cascades Region (Ingebritsen & Mariner, 2010) Exploration Activity Details Location Cascades Geothermal Region Exploration Technique Field Mapping Activity Date Usefulness not indicated DOE-funding Unknown References S. E. Ingebritsen, R. H. Mariner (2010) Hydrothermal Heat Discharge In The Cascade Range, Northwestern United States Retrieved from "http://en.openei.org/w/index.php?title=Field_Mapping_At_Cascades_Region_(Ingebritsen_%26_Mariner,_2010)&oldid=510730"

10

GEA Group | Open Energy Information  

Open Energy Info (EERE)

Group Group Place Bochum, Germany Zip 44809 Sector Biofuels, Solar Product Bochum-based, engineering group specialising in process engineering and components for the food, pharmaceutical and petrochemical industries. GEA through its subsidiaries is involved in the solar and biofuels sector. Coordinates 51.485955°, 7.210866° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":51.485955,"lon":7.210866,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

11

Active-region designs in quantum cascade lasers  

SciTech Connect (OSTI)

This paper analyses the development of active-region designs in quantum cascade lasers. Active-region designs have been demonstrated to date that employ various radiative transitions (vertical, diagonal, interminiband and interband). The lower laser level is depopulated through nonradiative transitions, such as one- or two-phonon (and even three-phonon) relaxation or bound state {yields} continuum transitions. Advances in active-region designs and energy diagram optimisation in the past few years have led to significant improvements in important characteristics of quantum cascade lasers, such as their output power, emission bandwidth, characteristic temperature and efficiency. (invited paper)

Zasavitskii, I I [P N Lebedev Physical Institute, Russian Academy of Sciences, Moscow (Russian Federation)

2012-10-31T23:59:59.000Z

12

SaGea | Open Energy Information  

Open Energy Info (EERE)

SaGea SaGea Jump to: navigation, search Name SaGea Place Cagliari, Italy Zip 9125 Sector Solar Product Cagliari-based PV developer that designs, installs and maintains equipment for solar energy generation for both private and corporate users. Coordinates 39.214525°, 9.110492° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":39.214525,"lon":9.110492,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

13

GEA Caldemon formerly known as Caldemon Iberica | Open Energy Information  

Open Energy Info (EERE)

Caldemon formerly known as Caldemon Iberica Caldemon formerly known as Caldemon Iberica Jump to: navigation, search Name GEA Caldemon (formerly known as Caldemon Iberica) Place Spain Sector Solar Product GEA Caldemon manufacturers shell and tube heat exchangers and surface condensers, commonly used in solar thermal power plants. References GEA Caldemon (formerly known as Caldemon Iberica)[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. GEA Caldemon (formerly known as Caldemon Iberica) is a company located in Spain . References ↑ "GEA Caldemon (formerly known as Caldemon Iberica)" Retrieved from "http://en.openei.org/w/index.php?title=GEA_Caldemon_formerly_known_as_Caldemon_Iberica&oldid=34572

14

Isotopic Analysis At Cascades Region (Kennedy & Van Soest, 2007) | Open  

Open Energy Info (EERE)

Analysis At Cascades Region (Kennedy & Van Soest, 2007) Analysis At Cascades Region (Kennedy & Van Soest, 2007) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Isotopic Analysis-Fluid At Cascades Region (Kennedy & Van Soest, 2007) Exploration Activity Details Location Cascades Geothermal Region Exploration Technique Isotopic Analysis- Fluid Activity Date Usefulness useful regional reconnaissance DOE-funding Unknown Notes The correspondence of helium isotope ratios and active transtensional deformation indicates a deformation-enhanced permeability and that mantle fluids can penetrate the ductile lithosphere, even in regions where there is no substantial magmatism. Superimposed on the regional trend are local, high 3He/4He anomalies indicating hidden magmatic activity and/or deep

15

The Geothermal Technologies Office Congratulates this Year's GEA Honors Awardees  

Broader source: Energy.gov [DOE]

On December 10, the Geothermal Energy Association announced its 2013 GEA Honors awards for advances and achievements in geothermal energy. Among this year's eleven winners and honorable mentions are five projects that the Energy Department investe

16

GEA Honors Geothermal Leaders | Department of Energy  

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

produce power and cascade the remaining energy to support an existing geothermal district heating system and future greenhouse and aquaculture businesses. If successful, Canby...

17

A quantum cascade laser in a transverse magnetic field. A model of the open triple-barrier active region  

Science Journals Connector (OSTI)

A theory of spectral parameters and active dynamic conductivity of the quantum cascade laser is proposed in the model of a triple-barrier active region of an individual cascade in a transverse magnetic field. In ...

N. V. Tkach; I. V. Boyko; Ju. A. Seti; G. G. Zegrya

2013-06-01T23:59:59.000Z

18

GRC Annual Meeting and GEA Geothermal Energy Expo | Department of Energy  

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

GRC Annual Meeting and GEA Geothermal Energy Expo GRC Annual Meeting and GEA Geothermal Energy Expo GRC Annual Meeting and GEA Geothermal Energy Expo September 29, 2013 12:00AM EDT to October 2, 2013 12:00PM EDT "A Global Resource, from Larderello to Las Vegas" This year's GRC Annual Meeting and GEA Geothermal Energy Expo will take place at the MGM Grand Hotel and Casino in Las Vegas, Nevada. This four-day event is industry's largest annual gathering of leading geothermal energy scientists, producers, renewable energy industry stakeholders, regulators, utilities, and key associated business leaders. Last year, it hosted representatives from more than 39 countries. Participants from six continents were present. In 2013, an even broader attendance is anticipated. The GRC Annual Meeting will offer technical, policy, and market conference

19

Akermanite in the Cascade Slide xenolith and its significance for regional metamorphism in the Adirondacks  

Science Journals Connector (OSTI)

Akermanite (Ak90) coexists with monticellite (Mo92) and wollastonite (Wo99...) in an unusual calc-silicate xenolith in anorthosite at Cascade Slide in the Adirondack Mountains, New York. Experimental results bear...

J. W. Valley; E. J. Essene

1980-01-01T23:59:59.000Z

20

Pulsed quantum-cascade-laser spectroscopy withintermediate-size pulses: application to NH3 in the 10?m region  

Science Journals Connector (OSTI)

Pulsed quantum-cascade-laser spectrometers are usually used to detect atmospheric...3 spectra recorded at low pressure (i.e. in the mbar range), the spectra show typical oscillations after the absorption. The Bee...

B. Grouiez; V. Zeninari; L. Joly; B. Parvitte

2010-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "region cascades gea" 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

Terahertz quantum cascade lasers  

Science Journals Connector (OSTI)

...Michael Pepper Terahertz quantum cascade lasers Jerome Faist 1 Lassaad Ajili...developments in terahertz quantum cascade lasers are reviewed. Structures...magnetic confinement| Terahertz quantum cascade lasers. | Recent developments in...

2004-01-01T23:59:59.000Z

22

Cascade Organic Solar Cells  

Science Journals Connector (OSTI)

Cascade Organic Solar Cells ... Multiple factors control the efficiency of organic solar cells, making it difficult to use single donor or acceptor materials to balance the, often opposing, material properties required to optimize device performance. ... We demonstrate planar organic solar cells consisting of a series of complementary donor materials with cascading exciton energies, incorporated in the following structure: glass/indium-tin-oxide/donor cascade/C60/bathocuproine/Al. ...

Cody W. Schlenker; Vincent S. Barlier; Stephanie W. Chin; Matthew T. Whited; R. Eric McAnally; Stephen R. Forrest; Mark E. Thompson

2011-09-02T23:59:59.000Z

23

Terahertz Quantum Cascade Lasers  

Science Journals Connector (OSTI)

We provide an overview of terahertz quantum cascade lasers based on resonant-phonon depopulation and metal-metal waveguides, including two-phonon resonant-phonon depopulation...

Williams, Benjamin; Kumar, Sushil; Qin, Qi; Lee, Alan Wei Min; Hu, Qing; Reno, John L; Wasilewski, Z R; Liu, H C

24

Terahertz quantum cascade lasers  

E-Print Network [OSTI]

The development of the terahertz frequency range has long been impeded by the relative dearth of compact, coherent radiation sources of reasonable power. This thesis details the development of quantum cascade lasers (QCLs) ...

Williams, Benjamin S. (Benjamin Stanford), 1974-

2003-01-01T23:59:59.000Z

25

Tunable External Cavity Interband Cascade Laser A. N. Chryssis, M. Dagenais  

E-Print Network [OSTI]

region with a tuning range of 300nm (208 cm-1 ). For comparison, a tunable quantum cascade laserTunable External Cavity Interband Cascade Laser A. N. Chryssis, M. Dagenais Photonics Switching be operated at TEC compatible temperatures. Interband Cascade (IC) lasers[2] , have shown exceptional

Dagenais, Mario

26

Colliding cascades model for earthquake prediction  

E-Print Network [OSTI]

cascades: a direct cascade of loading, which is applied to the top (largest) ... on a direct cascade that would deliver energy from the largest ...... Forest fires: an.

2000-10-12T23:59:59.000Z

27

Origin of InGaN/GaN light-emitting diode efficiency improvements using tunnel-junction-cascaded active regions  

SciTech Connect (OSTI)

This Letter investigates the efficiency enhancement achieved by tunnel junction insertion into the InGaN/GaN multi-quantum well (MQW) active region of blue light emitting diodes (LEDs). The peak quantum efficiency of such LED exceeds 100%, but the maximum wall-plug efficiency (WPE) hardly changes. However, due to the increased bias, the WPE peaks at much higher input power, i.e., the WPE droop is significantly delayed, and the output power is strongly enhanced. The main physical reason for this improvement lies in the non-uniform vertical carrier distribution typically observed within InGaN MQWs.

Piprek, Joachim, E-mail: piprek@nusod.org [NUSOD Institute LLC, P.O. Box 7204, Newark, Delaware 19714 (United States)

2014-02-03T23:59:59.000Z

28

Quantum dot cascade laser  

Science Journals Connector (OSTI)

We demonstrated an unambiguous quantum dot cascade laser based on InGaAs/GaAs/InAs/InAlAs heterostructure by making use of self-assembled quantum dots in the Stranski-Krastanow growth mode...??~?6.15?m and a bro...

Ning Zhuo; Feng Qi Liu; Jin Chuan Zhang; Li Jun Wang

2014-03-01T23:59:59.000Z

29

Electroluminescence of quantum-dash-based quantum cascade laser structures  

SciTech Connect (OSTI)

We developed two mid-infrared quantum cascade structures based on InAs quantum dashes. The dashes were embedded either in AlInGaAs lattice-matched to InP or in tensile-strained AlInAs. The devices emit between 7 and 11 {mu}m and are a step forward in the development of quantum cascade lasers based on 3-D confined active regions.

Liverini, V.; Bismuto, A.; Nevou, L.; Beck, M.; Faist, J. [Institute of Quantum Electronics, ETH Zurich, 8092 (Switzerland); Wolfgang-Pauli-Str. 16, HPT F 11, Zurich, CH-8093 (Switzerland)

2011-12-23T23:59:59.000Z

30

Plasmonic Quantum Cascade Laser Antenna  

Science Journals Connector (OSTI)

We demonstrate the plasmonic quantum cascade laser antenna, that can confine mid-infrared radiation beyond the diffraction limit, by integrating gold optical antennas on the laser...

Yu, Nanfang; Cubukcu, Ertugrul; Diehl, Laurent; Crozier, Kenneth; Capasso, Federico

31

Superlattice cascade solar cell  

SciTech Connect (OSTI)

This paper reports progress toward realization of a new cascade solar cell structure whose chief advantages over other present concepts are: use of silicon for the substrate and low bandgap cell; avoidance of the necessity of lattice matching; and incorporation of a GaAs/GaP superlattice to enhance efficiency and provide a low-resistance connecting junction. Details of the design and operation of an OMCVD system for growing this structure are presented. Results of experiments to optimize layer thickness, compositional uniformity, and surface morphology are described.

Wanlass, M.W.; Blakeslee, A.E.

1982-09-01T23:59:59.000Z

32

Quantum-cascade lasers enable infrared sensors  

SciTech Connect (OSTI)

Quantum-cascade lasers (QCLs) are semiconductor-injection lasers based on intersubband transitions in a multiple-quantum-well heterostructure. They are designed using band-structure engineering and grown by molecular beam epitaxy. The emission wavelength of a QCL is primarily a function of quantum-well thickness--thinner quantum wells lead to shorter wavelengths--and is essentially independent of the material bandgap. Quantum-cascade lasers can be designed to operate at any wavelength from 3.5 m (infrared) to 67 m (terahertz region) and are continuously tunable through ranges of a few inverse centimeters.1, 2, 3 This capability makes them well suited for spectroscopy in the infrared (see Laser Focus World, August 1999, p. 40).

Schultz, John F. (BATTELLE (PACIFIC NW LAB))

2003-05-01T23:59:59.000Z

33

Hydrothermal Heat Discharge In The Cascade Range, Northwestern United  

Open Energy Info (EERE)

Page Page Edit History Facebook icon Twitter icon » Hydrothermal Heat Discharge In The Cascade Range, Northwestern United States Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Hydrothermal Heat Discharge In The Cascade Range, Northwestern United States Details Activities (3) Areas (1) Regions (0) Abstract: Hydrothermal heat discharge in the Cascade Range includes the heat discharged by thermal springs, by "slightly thermal" springs that are only a few degrees warmer than ambient temperature, and by fumaroles. Thermal-spring heat discharge is calculated on the basis of chloride-flux measurements and geothermometer temperatures and totals ~ 240 MW in the U.S. part of the Cascade Range, excluding the transient post-1980 discharge

34

Multi-stage Cascaded Stirling Refrigerator  

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

Multi-stage Cascaded Stirling Refrigerator Multi-stage Cascaded Stirling Refrigerator Los Alamos National Laboratory (LANL) researchers have developed a multi-stage refrigerator,...

35

Electromagnetic cascades and cascade nucleosynthesis in the early Universe  

Science Journals Connector (OSTI)

We describe a calculation of electromagnetic cascading in radiation and matter in the early Universe initiated by the decay of massive particles or by some other process. We have used a combination of Monte Carlo and numerical techniques which enables us to use exact cross sections, where known, for all the relevant processes. In cascades initiated after the epoch of big bang nucleosynthesis ? rays in the cascades will photodisintegrate He4, producing He3 and deuterium. Using the observed He3 and deuterium abundances we are able to place constraints on the cascade energy deposition as a function of cosmic time. In the case of the decay of massive primordial particles we place limits on the density of massive primordial particles as a function of their mean decay time, and on the expected intensity of decay neutrinos.

R. J. Protheroe; T. Stanev; V. S. Berezinsky

1995-04-15T23:59:59.000Z

36

Demonstration of air-guided quantum cascade lasers without top claddings  

E-Print Network [OSTI]

Demonstration of air-guided quantum cascade lasers without top claddings V. Moreau1, M. Bahriz1, R Abstract: We report on quantum cascade lasers employing waveguides based on a predominant air confinement mechanism in which the active region is located immediately at the device top surface. The lasers employ

Painter, Oskar

37

Cascade redox flow battery systems  

DOE Patents [OSTI]

A reduction/oxidation ("redox") flow battery system includes a series of electrochemical cells arranged in a cascade, whereby liquid electrolyte reacts in a first electrochemical cell (or group of cells) before being directed into a second cell (or group of cells) where it reacts before being directed to subsequent cells. The cascade includes 2 to n stages, each stage having one or more electrochemical cells. During a charge reaction, electrolyte entering a first stage will have a lower state-of-charge than electrolyte entering the nth stage. In some embodiments, cell components and/or characteristics may be configured based on a state-of-charge of electrolytes expected at each cascade stage. Such engineered cascades provide redox flow battery systems with higher energy efficiency over a broader range of current density than prior art arrangements.

Horne, Craig R.; Kinoshita, Kim; Hickey, Darren B.; Sha, Jay E.; Bose, Deepak

2014-07-22T23:59:59.000Z

38

Valley Of Ten Thousand Smokes Region Geothermal Area | Open Energy  

Open Energy Info (EERE)

Valley Of Ten Thousand Smokes Region Geothermal Area Valley Of Ten Thousand Smokes Region Geothermal Area (Redirected from Valley Of Ten Thousand Smokes Region Area) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermal Resource Area: Valley Of Ten Thousand Smokes Region Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory and Environmental Issues 4 Exploration History 5 Well Field Description 6 Geology of the Area 7 Geofluid Geochemistry 8 NEPA-Related Analyses (0) 9 Exploration Activities (8) 10 References Area Overview Geothermal Area Profile Location: Alaska Exploration Region: Alaska Geothermal Region GEA Development Phase: 2008 USGS Resource Estimate Mean Reservoir Temp: Estimated Reservoir Volume: Mean Capacity: Click "Edit With Form" above to add content

39

Broadly tunable quantum cascade laser in cantilever-enhanced photoacoustic infrared spectroscopy of solids  

Science Journals Connector (OSTI)

An external cavity quantum cascade laser (EC-QCL) is applied in the...?1 (9701,646cm?1) in the mid-infrared region, which enables accurate broadband spectroscopy of large molecules. The high spectral power den...

J. Lehtinen; T. Kuusela

2014-06-01T23:59:59.000Z

40

MOLECULAR DYNAMICS SIMULATIONS OF DISPLACEMENT CASCADES IN MOLYBDENUM  

SciTech Connect (OSTI)

Molecular dynamics calculations have been employed to simulate displacement cascades in neutron irradiated Mo. A total of 90 simulations were conducted for PKA energies between 1 and 40 keV and temperatures from 298 to 923K. The results suggest very little effect of temperature on final defect count and configuration, but do display a temperature effect on peak defect generation prior to cascade collapse. Cascade efficiency, relative to the NRT model, is computed to lie between 1/4 and 1/3 in agreement with simulations performed on previous systems. There is a tendency for both interstitials and vacancies to cluster together following cascade collapse producing vacancy rich regions surrounded by interstitials. Although coming to rest in close proximity, the point defects comprising the clusters generally do not lie within the nearest neighbor positions of one another, except for the formation of dumbbell di-interstitials. Cascades produced at higher PKA energies (20 or 40 keV) exhibit the formation of subcascades.

Smith, Richard Whiting

2003-09-08T23:59:59.000Z

Note: This page contains sample records for the topic "region cascades gea" 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

Fire and the persistence and decline of montane chaparral in mixed conifer forests in the southern Cascades, Lassen Volcanic National Park, CA.  

E-Print Network [OSTI]

??Stands of montane chaparral are an integral component of the mixed conifer forest in the Cascade Mountains of northern California. In this region, chaparral stands (more)

Airey, Catherine

2012-01-01T23:59:59.000Z

42

Valley Of Ten Thousand Smokes Region Geothermal Area | Open Energy  

Open Energy Info (EERE)

Valley Of Ten Thousand Smokes Region Geothermal Area Valley Of Ten Thousand Smokes Region Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermal Resource Area: Valley Of Ten Thousand Smokes Region Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory and Environmental Issues 4 Exploration History 5 Well Field Description 6 Geology of the Area 7 Geofluid Geochemistry 8 NEPA-Related Analyses (0) 9 Exploration Activities (8) 10 References Area Overview Geothermal Area Profile Location: Alaska Exploration Region: Alaska Geothermal Region GEA Development Phase: 2008 USGS Resource Estimate Mean Reservoir Temp: Estimated Reservoir Volume: Mean Capacity: Click "Edit With Form" above to add content History and Infrastructure Operating Power Plants: 0 No geothermal plants listed.

43

Aeolian tones of a plate cascade  

Science Journals Connector (OSTI)

A model for the aeroacoustic resonance effects (aeolian tones) excited around a plate cascade in a gas flow is suggested. Methods of calculating the frequencies of natural acoustic oscillations near the cascade a...

S. V. Sukhinin

44

Synthesis of Cascade Refrigeration and Liquefaction Systems  

Science Journals Connector (OSTI)

Synthesis of Cascade Refrigeration and Liquefaction Systems ... Current Status and Perspectives of Liquefied Natural Gas (LNG) Plant Design ...

Francisco J. Barns; C. Judson King

1974-10-01T23:59:59.000Z

45

Interactive Synthesis of Cascade Refrigeration Systems  

Science Journals Connector (OSTI)

Interactive Synthesis of Cascade Refrigeration Systems ... Current Status and Perspectives of Liquefied Natural Gas (LNG) Plant Design ...

Wai Biu Cheng; Richard S. H. Mah

1980-07-01T23:59:59.000Z

46

Dynamic theory of cascades on finite clustered random networks with a threshold rule  

Science Journals Connector (OSTI)

Cascade dynamics on networks are usually analyzed statically to determine existence criteria for cascades. Here, the Watts model of threshold dynamics on random Erd?s-Rnyi networks is analyzed to determine the dynamic time evolution of cascades. The network is assumed to have a specific finite number of nodes n and is not assumed to be treelike. All combinations of threshold ?, network average nodal degree z, and seed sizes |S| from a single node up are included. The analysis permits study of network size effects and increased clustering coefficient. Several size effects not found by infinite network theory are predicted by the analysis and confirmed by simulations. In the region of ? and z where a single node can start a cascade, cascades are expanding, in the sense that each step flips a larger group than the previous step did. We show that this region extends to larger values of z than predicted by infinite network analyses. In the region where larger seeds are needed (size proportional to n), cascades begin by contracting: at the outset, each step flips fewer nodes than the previous step, but eventually the process reverses and becomes expanding. A critical mass that grows during the cascade beyond an easily-calculated threshold is identified as the cause of this reversal.

Daniel E. Whitney

2010-12-08T23:59:59.000Z

47

Engineering Light: Quantum Cascade Lasers  

ScienceCinema (OSTI)

Quantum cascade lasers are ideal for environmental sensing and medical diagnostic applications. Gmachl discusses how these lasers work, and their applications, including their use as chemical trace gas sensors. As examples of these applications, she briefly presents results from her field campaign at the Beijing Olympics, and ongoing campaigns in Texas, Maryland, and Ghana.

Claire Gmachl

2010-09-01T23:59:59.000Z

48

GaAsbased quantum cascade lasers  

Science Journals Connector (OSTI)

...N. Murdin GaAs-based quantum cascade lasers Sirtori H. Page C. Becker...state-of-the-art of GaAs-based quantum cascade lasers. These new light sources...2000.0739 GaAs-based quantum cascade lasers By C. Sirtori, H. Page...

2001-01-01T23:59:59.000Z

49

CASCADE OPTIMIZATION AND CONTROL OF BATCH REACTORS  

E-Print Network [OSTI]

CASCADE OPTIMIZATION AND CONTROL OF BATCH REACTORS Xiangming Hua, Sohrab Rohani and Arthur Jutan ajutan@uwo.ca Abstract: In this study, a cascade closed-loop optimization and control strategy for batch reactor. Using model reduction a cascade system is developed, which can effectively combine optimization

Jutan, Arthur

50

A multifrequency interband two-cascade laser  

SciTech Connect (OSTI)

Multifrequency lasing in a new class of injection heterolasers, i.e., in an interband two-cascade laser with a tunneling p-n junction separating two active regions of quantum wells located in the same waveguide is obtained and studied. The developed laser structure with pulsed pumping provided the simultaneous emission of two first-order modes with the wavelengths of 1.063 and 0.98 {mu}m and two third-order modes with the wavelengths of 0.951 and 0.894 {mu}m. Due to nonlinear mixing of the modes within the laser cavity, the generation of the second harmonics and sum frequencies was observed.

Biryukov, A. A.; Zvonkov, B. N.; Nekorkin, S. M.; Demina, P. B.; Semenov, N. N. [Research Physicotechnical Institute at the Nizhni Novgorod State University (Russian Federation); Aleshkin, V. Ya.; Gavrilenko, V. I.; Dubinov, A. A., E-mail: sanya@ipm.sci-nnov.ru; Marem'yanin, K. V.; Morozov, S. V. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation); Belyanin, A. A.; Kocharovsky, V. V. [Texas A and M University, Department of Physics (United States); Kocharovsky, Vl. V. [Russian Academy of Sciences, Institute of Applied Physics (Russian Federation)

2007-10-15T23:59:59.000Z

51

Village of Cascade | Open Energy Information  

Open Energy Info (EERE)

Cascade Cascade Jump to: navigation, search Name Village of Cascade Facility Village of Cascade Sector Wind energy Facility Type Community Wind Facility Status In Service Owner Village of Cascade Energy Purchaser Village of Cascade Location Cascade WI Coordinates 43.65868218°, -87.99709797° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":43.65868218,"lon":-87.99709797,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

52

Dual wavelength emission from a terahertz quantum cascade laser  

SciTech Connect (OSTI)

We describe a heterogeneous THz quantum cascade laser that is composed of two different active region designs. This device emits simultaneously at around 2.5 THz and 2.9 THz with a certain frequency tunability by applied current. We also investigate the spectral gain in the structure by THz time-domain spectroscopy and correlate the gain spectral bandwidth with the alignment and wavelength emission behaviour of the two stack device.

Freeman, Joshua R.; Brewer, Anthony; Marshall, Owen P.; Beere, Harvey E.; Ritchie, David A. [Semiconductor Physics, Cavendish Laboratory, University of Cambridge, JJ Thomson Avenue, Cambridge, CB3 0HE (United Kingdom); Madeo, Julien; Dhillon, Sukhdeep; Jukam, Nathan; Oustinov, Dimitri; Tignon, Jerome [Laboratoire Pierre Aigrain, Ecole Normale Suprieure, UMR 8551 CNRS, UPMC Univ. Paris 6 75005 Paris (France)

2011-12-23T23:59:59.000Z

53

Definition: Cascading Outage | Open Energy Information  

Open Energy Info (EERE)

Cascading Outage Cascading Outage Jump to: navigation, search Dictionary.png Cascading Outage The uncontrolled successive loss of system elements triggered by an incident at any location. Cascading results in widespread electric service interruption that cannot be restrained from sequentially spreading beyond an area predetermined by studies.[1] View on Wikipedia Wikipedia Definition A cascading failure is a failure in a system of interconnected parts in which the failure of a part can trigger the failure of successive parts. Such a failure may happen in many types of systems, including power transmission, computer networking, finance and bridges. Cascading failures usually begin when one part of the system fails. When this happens, nearby nodes must then take up the slack for the failed component. This overloads

54

Multiplexity-facilitated cascades in networks  

Science Journals Connector (OSTI)

Elements of networks interact in many ways, so modeling them with graphs requires multiple types of edges (or network layers). Here we show that such multiplex networks are generically more vulnerable to global cascades than simplex networks. We generalize the threshold cascade model [Watts, Proc. Natl. Acad. Sci. USA 99, 5766 (2002)] to multiplex networks, in which a node activates if a sufficiently large fraction of neighbors in any layer are active. We show that both combining layers (i.e., realizing other interactions play a role) and splitting a network into layers (i.e., recognizing distinct kinds of interactions) facilitate cascades. Notably, layers unsusceptible to global cascades can cooperatively achieve them if coupled. On one hand, this suggests fundamental limitations on predicting cascades without full knowledge of a system's multiplexity; on the other hand, it offers feasible means to control cascades by introducing or removing sparse layers in an existing network.

Charles D. Brummitt; Kyu-Min Lee; K.-I. Goh

2012-04-27T23:59:59.000Z

55

Contingency Analysis of Cascading Line Outage Events  

SciTech Connect (OSTI)

As the US power systems continue to increase in size and complexity, including the growth of smart grids, larger blackouts due to cascading outages become more likely. Grid congestion is often associated with a cascading collapse leading to a major blackout. Such a collapse is characterized by a self-sustaining sequence of line outages followed by a topology breakup of the network. This paper addresses the implementation and testing of a process for N-k contingency analysis and sequential cascading outage simulation in order to identify potential cascading modes. A modeling approach described in this paper offers a unique capability to identify initiating events that may lead to cascading outages. It predicts the development of cascading events by identifying and visualizing potential cascading tiers. The proposed approach was implemented using a 328-bus simplified SERC power system network. The results of the study indicate that initiating events and possible cascading chains may be identified, ranked and visualized. This approach may be used to improve the reliability of a transmission grid and reduce its vulnerability to cascading outages.

Thomas L Baldwin; Magdy S Tawfik; Miles McQueen

2011-03-01T23:59:59.000Z

56

Multiwavelength and supercontinuum quantum cascade lasers  

Science Journals Connector (OSTI)

Bandstructure engineering of intersubband optical transitions has led to a new class of quantum cascade lasers (QCL) that simultaneously emit multiple wavelengths by suitable...

Capasso, Federico; Gmachl, Claire; Sivco, Deborah; Cho, Al

57

Quantum Cascade Lasers: Coming of Age  

Science Journals Connector (OSTI)

The quantum cascade laser, first realized in 1994, has now demonstrated operation over an extremely wide wavelength range extending from the mid-infrared to the...

Faist, Jerome

58

Electrically tunable terahertz quantum cascade lasers  

E-Print Network [OSTI]

In this thesis, microelectromechanical systems (MEMS) assisted electrically tunable terahertz quantum cascade lasers (THz QCLs) are designed and demonstrated. Two MEMS tuner devices are proposed to achieve electrically ...

Han, Ningren

2013-01-01T23:59:59.000Z

59

Cascade Control and Defense in Complex Networks  

Science Journals Connector (OSTI)

Complex networks with a heterogeneous distribution of loads may undergo a global cascade of overload failures when highly loaded nodes or edges are removed due to attacks or failures. Since a small attack or failure has the potential to trigger a global cascade, a fundamental question regards the possible strategies of defense to prevent the cascade from propagating through the entire network. Here we introduce and investigate a costless strategy of defense based on a selective further removal of nodes and edges, right after the initial attack or failure. This intentional removal of network elements is shown to drastically reduce the size of the cascade.

Adilson E. Motter

2004-08-26T23:59:59.000Z

60

Heat Flow From Four New Research Drill Holes In The Western Cascades,  

Open Energy Info (EERE)

From Four New Research Drill Holes In The Western Cascades, From Four New Research Drill Holes In The Western Cascades, Oregon, Usa Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Journal Article: Heat Flow From Four New Research Drill Holes In The Western Cascades, Oregon, Usa Details Activities (1) Areas (1) Regions (0) Abstract: Conceptual models of the thermal structure of the Oregon Cascade Range propose either (1) a narrow zone of magmatic heat sources, flanked by shallow heat-flow anomalies caused by lateral ground-water flow; or (2) a wide zone of magmatic heat sources, with localized, generally negligible ground-water effects. The proposed narrow heat source coincides with the Quaternary volcanic arc, whereas the wider heat source would extend 10-30 km west of the arc. To test the models, four new heat-flow holes were sited

Note: This page contains sample records for the topic "region cascades gea" 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

Atomic-Scale Simulations of Cascade Overlap and Damage Evolution...  

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

Atomic-Scale Simulations of Cascade Overlap and Damage Evolution in Silicon Carbide. Atomic-Scale Simulations of Cascade Overlap and Damage Evolution in Silicon Carbide. Abstract:...

62

Multiple-junction quantum cascade photodetectors for thermophotovoltaic energy conversion  

Science Journals Connector (OSTI)

The use of intersubband transitions in quantum cascade structures for thermophotovoltaic energy conversion is investigated numerically. The intrinsic cascading scheme, spectral...

Yin, Jian; Paiella, Roberto

2010-01-01T23:59:59.000Z

63

Compact Quantum Cascade Laser Transmitter  

SciTech Connect (OSTI)

): In this paper we present design considerations, thermal and optical modeling results, and device performance for a ruggedized, compact laser transmitter that utilizes a room temperature quantum cascade (QC) laser source. The QC laser transmitter is intended for portable mid-infrared (3-12 m) spectroscopy applications, where the atmospheric transmission window is relatively free of water vapor interference and where the molecular rotational vibration absorption features can be used to detect and uniquely identify chemical compounds of interest. Initial QC laser-based sensor development efforts were constrained by the complications of cryogenic operation. However, improvements in both QC laser designs and fabrication processes have provided room-temperature devices that now enable significant miniaturization and integration potential for national security, environmental monitoring, atmospheric science, and industrial safety applications.

Anheier, Norman C.; Hatchell, Brian K.; Gervais, Kevin L.; Wojcik, Michael D.; Krishnaswami, Kannan; Bernacki, Bruce E.

2009-04-01T23:59:59.000Z

64

External cavity quantum cascade laser  

Science Journals Connector (OSTI)

In this paper we review the progress of the development of mid-infrared quantum cascade lasers (QCLs) operated in an external cavity configuration. We concentrate on QCLs based on the bound-to-continuum design, since this design is especially suitable for broadband applications. Since they were first demonstrated, these laser-based tunable sources have improved in performance in terms of output power, duty cycle, operation temperature and tuneability. Nowadays they are an interesting alternative to FTIRs for some applications. They operate at room temperature, feature a high spectral resolution while being small in size. They were successfully used in different absorption spectroscopy techniques. Due to their vast potential for applications in industry, medicine, security and research, these sources enjoy increasing interest within the research community as well as in industry.

Andreas Hugi; Richard Maulini; Jrme Faist

2010-01-01T23:59:59.000Z

65

US geothermal database and Oregon cascade thermal studies: (Final report)  

SciTech Connect (OSTI)

This report describes two tasks of different nature. The first of these tasks was the preparation of a data base for heat flow and associated ancillary information for the United States. This data base is being used as the basis for preparation of the United States portion of a geothermal map of North America. The ''Geothermal Map of North America'' will be published as part of the Decade of North American Geology (DNAG) series of the Geological Society of America. The second of these tasks was to make a geothermal evaluation of holes drilled in the Cascade Range as part of a Department of Energy (DOE)/Industry co-sponsored deep drilling project. This second task involved field work, making temperature logs in the holes, and laboratory work, measuring thermal conductivity measurements on an extensive set of samples from these holes. The culmination of this task was an interpretation of heat flow values in terms of the regional thermal conditions; implications for geothermal systems in the Cascade Range; evaluation of the effect of groundwater flow on the depths that need to be drilled for successful measurements in the Cascade Range; and investigation of the nature of the surface groundwater effects on the temperature-depth curves. 40 refs., 7 figs., 7 tabs.

Blackwell, D.D.; Steele, J.L.; Carter, L.

1988-05-01T23:59:59.000Z

66

Self-consistent thermal simulation of GaAs/Al0.45Ga0.55As quantum cascade lasers  

Science Journals Connector (OSTI)

This paper presents a self-consistent thermal model for quantum cascade lasers (QCLs) that takes into account the nonuniform heat generation distribution in the active region as well as the temperature dependences of the heat generation rate and thermal ... Keywords: Heating, Monte Carlo, Nonlinear effects, Phonon transport, Quantum cascade lasers, Thermal model

Y. B. Shi; Z. Aksamija; I. Knezevic

2012-03-01T23:59:59.000Z

67

Monitoring Alfvn Cascades with Interferometry on the JET Tokamak  

Science Journals Connector (OSTI)

A microwave interferometry technique is applied for the first time for detecting a discrete spectrum of Alfvn cascade (AC) eigenmodes excited with fast ions in reversed magnetic shear plasmas of the Joint European Torus. The interferometry measurements of plasma density perturbations associated with ACs show an unprecedented frequency and time resolution superior to that obtained with external magnetic coils. The measurements of ACs are used for monitoring the evolution of the safety factor and density of rational magnetic surfaces in the region of maximum plasma current.

S. E. Sharapov; B. Alper; J. Fessey; N. C. Hawkes; N. P. Young; R. Nazikian; G. J. Kramer; D. N. Borba; S. Hacquin; E. De La Luna; S. D. Pinches; J. Rapp; D. Testa; JET-EFDA Contributors

2004-10-12T23:59:59.000Z

68

Influence of nonparabolicity on electronic structure of quantum cascade laser  

Science Journals Connector (OSTI)

Abstract We analyze the influence of nonparabolicity on the bound electronic states in the conduction-band of quantum wells in external electric field. Numerical results, obtained by transfer matrix method are presented for active region of GaAs/Al0.3Ga0.7As quantum cascade laser. The structure was initially optimized by genetic algorithm, using Kane's model of nonparabolicity, with emission wavelength set to ? ? 15.1 ?m . However, our numerical results indicate the change in lasing wavelength to 14.04 ?m when using a more comprehensive description of nonparabolicity.

Nikola Vukovi?; Vitomir Milanovi?; Jelena Radovanovi?

2014-01-01T23:59:59.000Z

69

Unsteady aerodynamic analysis of subsonic oscillating cascade  

SciTech Connect (OSTI)

This paper describes the development of the source-doublet-based potential paneling method for oscillating cascade unsteady aerodynamic load predictions. By using the integral influence coefficient method and by using the interblade phase angles, the unsteady loads on an oscillating cascade can be accurately predicted at a minimum cost. As the grids are placed only on the blade surfaces, the blades are allowed to vibrate without grid deformation problems. Four notable subsonic oscillating cascade test cases that cover most important parameters, e.g., blade geometry, interblade phase angle, flow coefficient, flow speed, frequency, etc., are studied in this paper. The agreement between the present solutions and other numerical/experimental results demonstrates the robustness of the present model. Applicability of the method for realistic compressible flow cascades is also discussed.

Chen, S.H.; Eastland, A.H.; Jackson, E.D. (Rockwell International Corp., Canoga Park, CA (United States). Rocketdyne Div.)

1994-07-01T23:59:59.000Z

70

Product Lifecycle Approach to Cascade Impaction Measurements  

Science Journals Connector (OSTI)

During development of an orally inhaled product (OIP), its full-resolution Aerodynamic Particle Size...in vitro performance (1,2). The pharmacopeial eight-stage Andersen Cascade Impactor (ACI) or Next-Generation ...

Terrence P. Tougas; Dave Christopher; Jolyon Mitchell

2011-03-01T23:59:59.000Z

71

Modeling techniques for quantum cascade lasers  

E-Print Network [OSTI]

Quantum cascade lasers are unipolar semiconductor lasers covering a wide range of the infrared and terahertz spectrum. Lasing action is achieved by using optical intersubband transitions between quantized states in specifically designed multiple-quantum-well heterostructures. A systematic improvement of quantum cascade lasers with respect to operating temperature, efficiency and spectral range requires detailed modeling of the underlying physical processes in these structures. Moreover, the quantum cascade laser constitutes a versatile model device for the development and improvement of simulation techniques in nano- and optoelectronics. This review provides a comprehensive survey and discussion of the modeling techniques used for the simulation of quantum cascade lasers. The main focus is on the modeling of carrier transport in the nanostructured gain medium, while the simulation of the optical cavity is covered at a more basic level. Specifically, the transfer matrix and finite difference methods for solvin...

Jirauschek, Christian

2014-01-01T23:59:59.000Z

72

Quantum Cascade Lasers Emitting below 3 m  

Science Journals Connector (OSTI)

First quantum cascade lasers emitting below 3 m are demonstrated. The lasers based on the InAs/AlSb material system emit at 2.95-2.97 m at 83 K and operate up to room temperature.

Devenson, Jan; Teissier, Roland; Cathabard, Olivier; Baranov, Alexei N

73

Emission spectra of terahertz quantum cascade laser  

Science Journals Connector (OSTI)

We calculated energy levels, wave functions, and energies of radiative transitions in terahertz quantum cascade lasers based on GaAs/Al0.15Ga0.85As heterostructures. Current-voltage characteristics and current de...

A. V. Antonov; V. I. Gavrilenko; A. V. Ikonnikov

2009-07-01T23:59:59.000Z

74

Frequency tuning of THz quantum cascade lasers  

Science Journals Connector (OSTI)

Tunable single-mode THz quantum cascade lasers are crucial for spectroscopy applications. Current and temperature tuning are limited to a few GHz and other solutions have to be...

Tredicucci, Alessandro

75

Cascade Municipal Utilities | Open Energy Information  

Open Energy Info (EERE)

Cascade Municipal Utilities Cascade Municipal Utilities Jump to: navigation, search Name Cascade Municipal Utilities Place Iowa Utility Id 3137 Utility Location Yes Ownership M NERC Location MRO NERC MRO Yes ISO MISO Yes Operates Generating Plant Yes Activity Generation Yes Activity Transmission Yes Activity Distribution Yes References EIA Form EIA-861 Final Data File for 2010 - File1_a[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Utility Rate Schedules Grid-background.png All Electric Rate Residential City/Interdept. Rate Commercial Commercial Rate 3-phase Commercial Commercial Rate Single-phase Commercial Demand Rate Industrial Residential Rates Residential Average Rates Residential: $0.1040/kWh

76

SPONTANEOUS CURRENT-LAYER FRAGMENTATION AND CASCADING RECONNECTION IN SOLAR FLARES. I. MODEL AND ANALYSIS  

SciTech Connect (OSTI)

Magnetic reconnection is commonly considered to be a mechanism of solar (eruptive) flares. A deeper study of this scenario reveals, however, a number of open issues. Among them is the fundamental question of how the magnetic energy is transferred from large, accumulation scales to plasma scales where its actual dissipation takes place. In order to investigate this transfer over a broad range of scales, we address this question by means of a high-resolution MHD simulation. The simulation results indicate that the magnetic-energy transfer to small scales is realized via a cascade of consecutively smaller and smaller flux ropes (plasmoids), analogous to the vortex-tube cascade in (incompressible) fluid dynamics. Both tearing and (driven) 'fragmenting coalescence' processes are equally important for the consecutive fragmentation of the magnetic field (and associated current density) into smaller elements. At the later stages, a dynamic balance between tearing and coalescence processes reveals a steady (power-law) scaling typical of cascading processes. It is shown that cascading reconnection also addresses other open issues in solar-flare research, such as the duality between the regular large-scale picture of (eruptive) flares and the observed signatures of fragmented (chaotic) energy release, as well as the huge number of accelerated particles. Indeed, spontaneous current-layer fragmentation and the formation of multiple channelized dissipative/acceleration regions embedded in the current layer appear to be intrinsic to the cascading process. The multiple small-scale current sheets may also facilitate the acceleration of a large number of particles. The structure, distribution, and dynamics of the embedded potential acceleration regions in a current layer fragmented by cascading reconnection are studied and discussed.

Barta, Miroslav; Buechner, Joerg [Max Planck Institute for Solar System Research, D-37191 Katlenburg-Lindau (Germany); Karlicky, Marian; Skala, Jan, E-mail: barta@mps.mpg.de [Astronomical Institute of the Academy of Sciences of the Czech Republic, CZ-25165 Ondrejov (Czech Republic)

2011-08-10T23:59:59.000Z

77

Hydrothermal monitoring data from the Cascade Range, northwestern United States  

E-Print Network [OSTI]

Hydrothermal monitoring data from the Cascade Range, northwestern United States By S.E. Ingebritsen., and Evans, W.C., 2014, Hydrothermal monitoring data from the Cascade Range, northwestern United States: U ...................................................................................................................................27 (8) Carbonate springs

78

Cascade County Secondary Data Analysis  

E-Print Network [OSTI]

prevalence (Heart Attack) 4.0% 4.1% 6.0% All Sites Cancer 461.9 (Region 2) 455.5 543.2 1 Community Johnson Foundation (2012) Leading Causes of Death County1 Montana1,2 Nation2 1. Cancer 2. Heart Disease 3. CLRD* 1. Cancer 2. Heart Disease 3.CLRD* 1. Heart Disease 2. Cancer 3. CLRD* #12

Maxwell, Bruce D.

79

Energy Cascading Combined with Thermal Energy Storage in Industry  

Science Journals Connector (OSTI)

The opportunities for energy conservation through the application of storage cascades has not previously been examined in...

R. J. Wood; D. T. Baldwin; P. W. OCallaghan

1983-01-01T23:59:59.000Z

80

FY 2005 Quantum Cascade Laser Alignment System Final Report  

SciTech Connect (OSTI)

The Alignment Lasers Task of Pacific Northwest National Laboratory's (PNNL's) Remote Spectroscopy Project (Project PL211I) is a co-funded project between DOE NA-22 and a Classified Client. This project, which began in the second half of FY03, involved building and delivering a Quantum Cascade (QC) Laser Alignment System to be used for testing the pupil alignment of an infrared sensor by measuring the response from four pairs of diametrically opposed QC lasers. PNNL delivered the system in FY04 and provided technical assistance in FY05 culminating into a successful demonstration of the system. This project evolved from the Laser Development Task of PL211I, which is involved in developing novel laser technology to support development of advanced chemical sensors for detecting the proliferation of nuclear weapons. The laser systems are based on quantum cascade (QC) lasers, a new semiconductor source in the infrared. QC lasers can be tailored to emit light throughout the infrared region (3.5 ? 17 ?m) and have high output power and stability. Thus, these lasers provide an infrared source with superb power and spectral stability enabling them to be used for applications such as alignment and calibration in addition to chemical sensing.

Myers, Tanya L.; Cannon, Bret D.; Wojcik, Michael D.; Broocks, Bryan T.; Stewart, Timothy L.; Hatchell, Brian K.

2006-01-11T23:59:59.000Z

Note: This page contains sample records for the topic "region cascades gea" 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

Classical Radiative Cascade in Antiproton Atoms  

SciTech Connect (OSTI)

An interrelation between radiative cascade transitions and annihilation rates in antiproton atoms is considered. The population of antiproton atom energy levels is described by a classical distribution function f(n,l), determining intensities of spectral lines in antiproton atoms. A strong dependence of spectral line intensities on the nuclear size is shown which could be used for the determination of effective nuclear radius.

Bureyeva, L. [Institute of Spectroscopy of the RAS, Troitsk, Moscow Reg., 142190 (Russian Federation); Lisitsa, V. [Nuclear Fusion Institute, Russian Research Center 'Kurchatov Institute' Moscow (Russian Federation); Putlitz, G. zu [Physikalisches Institut, Universitaet Heidelberg, Philosophenweg 12, 69120 Heidelberg (Germany)

2005-10-26T23:59:59.000Z

82

Emission Measurement with Quantum Cascade Laser  

Science Journals Connector (OSTI)

With the Mexa-1400QL-NX Horiba offers a new exhaust gas measurement solution which is based on the Quantum Cascade Laser technology. The new method is able to...2, N2O and NH3 emissions and is a tool for research...

Matthias Schrder; Dipl.-Phys. Daniel Scheder; Werner Czika

2011-05-01T23:59:59.000Z

83

Sequential resonant tunneling in quantum cascade lasers  

SciTech Connect (OSTI)

A model of sequential resonant tunneling transport among two-dimensional subbands that takes into account explicitly elastic scattering is investigated. It is compared to transport measurements performed on quantum cascade lasers, where resonant tunneling processes are known to be dominating. Excellent agreement is found between experiment and theory over a large range of current, temperature, and device structures.

Terazzi, Romain; Gresch, Tobias; Wittmann, Andreas; Faist, Jerome [Quantum Optoelectronics Group, Institute for Quantum Electronics, ETH, 8086 Zuerich (Switzerland)

2008-10-15T23:59:59.000Z

84

13 - Terahertz (THz) quantum cascade lasers  

Science Journals Connector (OSTI)

Abstract: This chapter is dedicated to terahertz (THz) quantum cascade laser technology. After a brief introduction that contains a description of the current state of the art in terms of performance, the following important technological aspects are reviewed in more detail: waveguide and photonic structures, frequency and phase stabilisation, and active mode-locking.

S. Barbieri; S. Kumar

2013-01-01T23:59:59.000Z

85

Cascaded frequency doublers for broadband laser radiation  

SciTech Connect (OSTI)

A new scheme of a cascaded converter of the first harmonic of broadband cw laser radiation into the second harmonic (SH) with compensation for the group walk-off in cascades is proposed and investigated. The conditions under which high conversion coefficients of broadband ({approx}33 cm{sup -1}) single-mode fibre laser radiation with low peak power ({approx}300 W) into the SH are determined for frequency doublers based on the most promising LBO crystal. Conversion of cw radiation with an average power of 300 W and efficiency {eta} = 4.5 % into the SH is obtained in a single LBO crystal. Effect of coherent addition of SH radiation excited in different cascades is demonstrated for two- and three-stage schemes. The expected conversion efficiencies, calculated disregarding loss but taking into account real aberrations of elements, are 18 % and 38 %, respectively. The effect of pumping depletion begins to manifest itself in the third cascade of a three-stage converter; it may reduce the latter value to {approx}30 %. (nonlinear optical phenomena)

Andreev, N F; Vlasova, K V; Davydov, V S; Kulikov, S M; Makarov, A I; Sukharev, Stanislav A; Freidman, Gennadii I; Shubin, S V

2012-10-31T23:59:59.000Z

86

Multiperiod quantum-cascade nanoheterostructures: Epitaxy and diagnostics  

SciTech Connect (OSTI)

Advances in the production technology of multiperiod nanoheterostructures of quantum-cascade lasers with 60 cascades by molecular-beam epitaxy (MBE) on an industrial multiple-substrate MBE machine are discussed. The results obtained in studying the nanoheterostructures of quantum-cascade lasers by transmission electron microscopy, high-resolution X-ray diffraction analysis, and photoluminescence mapping are presented.

Egorov, A. Yu., E-mail: Anton@beam.ioffe.ru; Brunkov, P. N.; Nikitina, E. V.; Pirogov, E. V.; Sobolev, M. S.; Lazarenko, A. A. [Russian Academy of Sciences, St. Petersburg Academic University, Nanotechnology Research and Education Center (Russian Federation); Baidakova, M. V.; Kirilenko, D. A.; Konnikov, S. G. [Russian Academy of Sciences, Ioffe Physical-Technical Institute (Russian Federation)

2014-12-15T23:59:59.000Z

87

STATEMENT OF CONSIDERATIONS REQUEs·r BY CASCADE ENGINEERI NG, INC. (CASCADE) FOR AN ADVANCE  

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

REQUEs·r BY CASCADE ENGINEERI REQUEs·r BY CASCADE ENGINEERI NG, INC. (CASCADE) FOR AN ADVANCE WA IVER OF DOMESTIC AND FORE IGN PATENT RIGHTS UNDER DOE AWARD NO. DE-EE0005440; W(A) 201 1-070 CASCAD E has requested a waiver of domesti c and fore ign patent rights of the United States of America in all subject inventions arising from its participation under the above refe renced cooperative agreeme nt entitl ed " Innovative Ballasted Flat Roof Solar PV Racking System." According to the Statement o f Project Objectives, the objectives of the project funded by the cooperative agreement arc to " [ dlesign, develop, engineer, manufacture, and market a flat roof so lar PV racking sys tem. This racking system will o±Ier a cost advantage from a materials and installation labor (mechanical and electrical) perspective. It will be flexible enough to

88

Broadband Distributed Feedback Quantum Cascade Laser Array Using a Heterogeneous Cascade  

Science Journals Connector (OSTI)

We demonstrated an array of distributed feedback quantum cascade lasers covering a spectral range of 220cm-1. The variability in threshold current and slope efficiency is explained in...

Diehl, Laurent; Lee, Benjamin G; Zhang, Haifei A; Pflgl, Christian; Belkin, Mikhail; Fisher, Milan; Wittman, Andreas; Faist, Jerome; Capasso, Federico

89

DETAILED COMPARISON BETWEEN PARTON CASCADE AND HADRONIC CASCADE AT SPS AND RHIC.  

SciTech Connect (OSTI)

The authors study the importance of the partonic phase produced in relativistic heavy ion collision by comparing the parton cascade model and the hadronic cascade model. Hadron yield, baryon stopping and transverse momentum distribution are calculated with JAM and discussions are given comparing with VNI. Both of these models give good description of experimental data. They also discuss the strangeness production mechanism and the directed transverse flow.

NARA,Y.

1998-10-23T23:59:59.000Z

90

Investigation of the thermal regime and geologic history of the Cascade volcanic arc: First phase of a program for scientific drilling in the Cascade Range  

SciTech Connect (OSTI)

A phased, multihole drilling program with associated science is proposed as a means of furthering our understanding of the thermal regime and geologic history of the Cascade Range of Washington, Oregon, and northern California. The information obtained from drilling and ancillary geological and geophysical investigations will contribute to our knowledge in the following general areas: (1) the magnitude of the regional background heat flow of parts of the Quaternary volcanic belt dominated by the most abundant volcanic rock types, basalt and basaltic andesite; (2) the nature of the heat source responsible for the regional heat-flow anomaly; (3) the characteristics of the regional hydrothermal and cold-water circulation; the rates of volcanism for comparison with models for the rate and direction of plate convergence of the Cascades; (5) the history of deformation and volcanism in the volcanic arc that can be related to subduction; (6) the present-day stress regime of the volcanic arc and the relation of these stresses to plate interactions and possible large earthquakes; and the current geometry of the subducted oceanic plate below the Cascade Range and the relationship of the plate to the distribution of heat flow, Quaternary volcanism, and Quaternary deformation. Phase I research will be directed toward a detailed investigation of the Santiam Pass segment. In concert with the Santiam Pass research, a detailed study of the nearby Breitenbush Hot Springs area is also recommended as a component of Phase I. The object of the Breitenbush research is to study one of the hottest known Cascade hydrothermal systems, which coincidentally also has a good geological and geophysical data base. A coordinated program of drilling, sampling, subsurface measurements, and surface surveys will be associated with the drilling of several holes.

Priest, G.R.

1987-01-01T23:59:59.000Z

91

Category:Geothermal Regions | Open Energy Information  

Open Energy Info (EERE)

Geothermalpower.jpg Geothermalpower.jpg Looking for the Geothermal Regions page? For detailed information on Geothermal Regions, click here. Category:Geothermal Regions Add.png Add a new Geothermal Region Pages in category "Geothermal Regions" The following 22 pages are in this category, out of 22 total. A Alaska Geothermal Region C Cascades Geothermal Region Central Nevada Seismic Zone Geothermal Region G Gulf of California Rift Zone Geothermal Region H Hawaii Geothermal Region Holocene Magmatic Geothermal Region I Idaho Batholith Geothermal Region N Northern Basin and Range Geothermal Region N cont. Northern Rockies Geothermal Region Northwest Basin and Range Geothermal Region O Outside a Geothermal Region R Rio Grande Rift Geothermal Region S San Andreas Geothermal Region San Andreas Split Geothermal Region

92

Remote Chemical Sensing Using Quantum Cascade Lasers  

SciTech Connect (OSTI)

Research done by the IR sensors team at PNNL is focused on developing advanced spectroscopic methods for detecting signatures of nuclear, chemical, biological and explosives weapons or weapons production. The sensors we develop fall into two categories: remote sensors that can be operated at distances ranging from 150 m to 10 km, and point sensors that are used for in-situ inspection and detection. FY03 has seen an explosion in FM DIAL progress with the net result being solid confirmation that FM DIAL is a technique capable of remote chemical monitoring in a wide variety of venues. For example, FM DIAL was used to detect a small plume of hydrogen sulfide, a candidate CW agent, released in the desert environment of the Hanford 200 Area site. These experiments were conducted over a range of physical conditions including outside temperatures ranging from 70 F to 105 F and turbulence conditions ranging from quiescent to chaotic. We are now rapidly developing the information needed to design prototype FM DIAL systems that are optimized for specific applications that include scenarios such as fixed position stand-off detection and mobile UAV mounted remote monitoring. Just as an example, in FY04 we will use FM DIAL to detect both in-facility and outdoor release of enriched UF6. The rapid progress in FM DIAL research made in FY03 is attributed to several advances. First, final construction of a custom-designed trailer allowed the instrument to be housed in a mobile temperature-controlled environment. This allowed the experiment to be transported to several locations so that data could be collected under a range of physical conditions. This has led to a better understanding of a variety of experimental noise sources. With this knowledge, we have been able to implement several changes in the way the FM DIAL data is collected and processed, with the net result being a drastic improvement in our confidence of analyte concentration measurement and an improvement i n the instrument detection limit. The range of chemicals detectable by FM DIAL has also been extended. Prior to FY03 only water and nitrous oxide (N2O) had been seen. Experiments on extending the tuning range of the quantum cascade laser (QCL) currently used in the experiments demonstrate that many more species are now accessible including H2S, C2F4H2, and CH4. We additionally demonstrated that FM DIAL measurements can be made using short wave infrared (SWIR) telecommunications lasers. While measurements made using these components are noisier because turbulence and particulate matter cause more interference in this spectral region, monitoring in this region enables larger species to be detected simply because these lasers have a greater tuning range. In addition, SWIR monitoring also allows for the detection of second-row hydride species such as HF and HCl, which are important nuclear and CWA proliferation signatures.

Harper, Warren W.; Strasburg, Jana D.; Aker, Pam M.; Schultz, John F.

2004-01-20T23:59:59.000Z

93

A relativistic cascade for heavy ion collisions  

SciTech Connect (OSTI)

Au on Au collisions at the BNL/AGS (11.6 GeV-A/c) are expected to produce a short-lived state of matter at high baryon density. If the baryons reach sufficiently high density, they may produce a quark-gluon plasma (QGP). The signals from a QGP phase may be difficult to distinguish from those of ordinary hadronic matter. The authors have constructed a relativistic cascade (ARC) for hadrons in an attempt to model the dynamics of ordinary hadronic matter in a heavy ion collision, in the hopes that deviations from the cascade results may indicate new physics. In this contribution the authors discuss the formation of high baryon density matter, and its effect on antiproton production.

Schlagel, T.J.; Pang, Y.; Kahana, S.H.

1994-07-01T23:59:59.000Z

94

Cascade Apartments: Deep Energy Multifamily Retrofit  

SciTech Connect (OSTI)

In December of 2009-10, King County Housing Authority (KCHA) implemented energy retrofit improvements in the Cascade multifamily community, located in Kent, Washington (marine climate.)This research effort involved significant coordination from stakeholders KCHA, WA State Department of Commerce, utility Puget Sound Energy, and Cascade tenants. This report focuses on the following three primary BA research questions : 1. What are the modeled energy savings using DOE low income weatherization approved TREAT software? 2. How did the modeled energy savings compare with measured energy savings from aggregate utility billing analysis? 3. What is the Savings to Investment Ratio (SIR) of the retrofit package after considering utility window incentives and KCHA capitol improvement funding.

Gordon, A.; Mattheis, L.; Kunkle, R.; Howard, L.; Lubliner, M.

2014-02-01T23:59:59.000Z

95

Cascade-based attacks on complex networks  

Science Journals Connector (OSTI)

We live in a modern world supported by large, complex networks. Examples range from financial markets to communication and transportation systems. In many realistic situations the flow of physical quantities in the network, as characterized by the loads on nodes, is important. We show that for such networks where loads can redistribute among the nodes, intentional attacks can lead to a cascade of overload failures, which can in turn cause the entire or a substantial part of the network to collapse. This is relevant for real-world networks that possess a highly heterogeneous distribution of loads, such as the Internet and power grids. We demonstrate that the heterogeneity of these networks makes them particularly vulnerable to attacks in that a large-scale cascade may be triggered by disabling a single key node. This brings obvious concerns on the security of such systems.

Adilson E. Motter and Ying-Cheng Lai

2002-12-20T23:59:59.000Z

96

Cascade Training Technique for Particle Identification  

E-Print Network [OSTI]

The cascade training technique which was developed during our work on the MiniBooNE particle identification has been found to be a very efficient way to improve the selection performance, especially when very low background contamination levels are desired. The detailed description of this technique is presented here based on the MiniBooNE detector Monte Carlo simulations, using both artifical neural networks and boosted decision trees as examples.

Yong Liu; Ion Stancu

2006-11-27T23:59:59.000Z

97

Two Dimensional Integration of Ring Cavity Surface Emitting Quantum Cascade Lasers  

SciTech Connect (OSTI)

The continual improvements over the last fifteen years have made quantum cascade lasers reliable and versatile light sources in the mid infrared and the terahertz spectral regions. In this work we present our latest results regarding the implementation of these light sources for forming broad band emitting two-dimensional laser arrays. A spectral tuning range of 180 cm{sup -1} around the centered wavelength of 8.2 {mu}m could be shown.

Schwarzer, Clemens; Mujagic, Elvis; Zederbauer, Tobias; Detz, Hermann; Andrews, Aaron M.; Schrenk, Werner; Strasser, Gottfried [Institute for Solid State Electronics, Vienna University of Technology, 1040 Vienna (Austria); Yao Yu; Chen Jianxin; Gmachl, Claire [Department of Electrical Engineering, Princeton University, Princeton, NJ 08544 (United States)

2011-12-26T23:59:59.000Z

98

Los Azufres Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

(0) 10 References Area Overview Geothermal Area Profile Location: Michoaciin, Mexico Exploration Region: Transmexican Volcanic Belt GEA Development Phase: Coordinates:...

99

EM to Proceed with Demolition Following Completion of Cascade Cleanout  

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

to Proceed with Demolition Following Completion of Cascade to Proceed with Demolition Following Completion of Cascade Cleanout Operations EM to Proceed with Demolition Following Completion of Cascade Cleanout Operations July 1, 2012 - 12:00pm Addthis X-326 Facility Manager Jack Tully, left to right, DOE Site Lead Joel Bradburne and Operator Russ Nickell stand in the local control room after the last processing equipment that had been operating in the uranium enrichment cascade at the Portsmouth site in Piketon was shut down. X-326 Facility Manager Jack Tully, left to right, DOE Site Lead Joel Bradburne and Operator Russ Nickell stand in the local control room after the last processing equipment that had been operating in the uranium enrichment cascade at the Portsmouth site in Piketon was shut down. The last equipment that had been operating in the uranium enrichment cascade at the Portsmouth site in Piketon was powered off May 30 after more than 57 years of operation.

100

CONTROL OF POLLUTANT EMISSIONS IN NATURAL GAS DIFFUSION FLAMES BY USING CASCADE BURNERS  

SciTech Connect (OSTI)

The goal of this exploratory research project is to control the pollutant emissions of diffusion flames by modifying the air infusion rate into the flame. The modification was achieved by installing a cascade of venturis around the burning gas jet. The basic idea behind this technique is controlling the stoichiometry of the flame through changing the flow dynamics and rates of mixing in the combustion zone with a set of venturis surrounding the flame. A natural gas jet diffusion flame at burner-exit Reynolds number of 5100 was examined with a set of venturis of specific sizes and spacing arrangement. The thermal and composition fields of the baseline and venturi-cascaded flames were numerically simulated using CFD-ACE+, an advanced computational environment software package. The instantaneous chemistry model was used as the reaction model. The concentration of NO was determined through CFD-POST, a post processing utility program for CFD-ACE+. The numerical results showed that, in the near-burner, midflame and far-burner regions, the venturi-cascaded flame had lower temperature by an average of 13%, 19% and 17%, respectively, and lower CO{sub 2} concentration by 35%, 37% and 32%, respectively, than the baseline flame. An opposite trend was noticed for O{sub 2} concentration; the cascaded flame has higher O{sub 2} concentration by 7%, 26% and 44%, in average values, in the near-burner, mid-flame and far-burner regions, respectively, than in the baseline case. The results also showed that, in the near-burner, mid-flame, and far-burner regions, the venturi-cascaded flame has lower NO concentrations by 89%, 70% and 70%, in average values, respectively, compared to the baseline case. The numerical results substantiate that venturi-cascading is a feasible method for controlling the pollutant emissions of a burning gas jet. In addition, the numerical results were useful to understand the thermo-chemical processes involved. The results showed that the prompt-NO mechanism plays an important role besides the conventional thermal-NO mechanism. The computational results of the present study need to be validated experimentally.

Dr. Ala Qubbaj

2001-12-30T23:59:59.000Z

Note: This page contains sample records for the topic "region cascades gea" 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

Cascading Failures in Power Grid under Three Node Attack Strategies  

Science Journals Connector (OSTI)

This paper studies cascading failures of power grid under three node attack strategies based on...k is k ? , and ?...is a tunable parameter. We investigated the...

Sui-Min Jia; Yun-Ye Wang; Cong Feng; Zhi-Juan Jia

2014-01-01T23:59:59.000Z

102

Building America Whole-House Solutions for Existing Homes: Cascade...  

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

Building America Whole-House Solutions for Existing Homes: Cascade Apartments - Deep Energy Multifamily Retrofit (Fact Sheet) Building America Whole-House Solutions for Existing...

103

Identifying two steps in the internal wave energy cascade  

E-Print Network [OSTI]

1.1.1 The internal wave energy cascade . . . . . . .? ? , which contain only wave energy trav- eling upward anddistinction is made between wave energy propagating upward

Sun, Oliver Ming-Teh

2010-01-01T23:59:59.000Z

104

Random?walk model of isotope enrichment in cascades  

Science Journals Connector (OSTI)

Steady opertional parameters such as enrichment flow rates isotopic distributions in the product and in the waste and their variation over the cascade are evaluated in terms of transit probabilities and average transit times of different gas molecules in their random walk from one stage to another of a cascade. The random?walk model is also used for describing transient properties i.e. the output response to input perturbation and the relaxation time. Calculations in terms of the model are carried out for UF6 of natural abundance enriched in a diffusion cascade. With the appropriate numerical values the model can also be applied to centrifuge cascades.

I. Kiss; Sz. Vass

1977-01-01T23:59:59.000Z

105

Active wavelength control of an external cavity quantum cascade laser  

Science Journals Connector (OSTI)

Semiconductor lasers are increasingly popular as components of high...1]. Quantum Cascade Lasers (QCLs) are particularly attractive semiconductor lasers, since their operating wavelengths in the mid...2...]. For ...

T. Tsai; G. Wysocki

2012-11-01T23:59:59.000Z

106

Low-Divergence Surface-Emitting Terahertz Quantum Cascade Lasers  

Science Journals Connector (OSTI)

We investigate surface-emission via a second-order grating in terahertz quantum cascade lasers. We optimize grating design and suppress facet reflectivity with absorbing waveguide...

Fan, Jonathan; Belkin, Mikhail; Capasso, Federico; Khanna, Suraj; Lachab, Mohammed; Davies, Giles; Linfield, Edmund

107

Chirped Laser Dispersion Spectroscopy with Directly Modulated Quantum Cascade Laser  

Science Journals Connector (OSTI)

A feasibility study of chirped laser dispersion spectroscopy (CLaDS) with utilizing direct modulation of a quantum cascade laser instead of external modulators is presented....

Hangauer, Andreas; Spinner, Georg; Nikodem, Michal; Wysocki, Gerard

108

Current Injection Spiral-Shaped Chaotic Microcavity Quantum Cascade Lasers  

Science Journals Connector (OSTI)

We report room temperature operation of current-injection quantum cascade lasers with spiral-shaped chaotic microresonators, capable of directional, single mode emission, operating...

Belkin, Mikhail A; Audet, Ross M; Fan, Jonathan A; Capasso, Federico; Narimanov, Evgenii; Bour, D; Corzine, S; Zhu, J; Hfler, G

109

Hydrothermal Heat Discharge In The Cascade Range, Northwestern...  

Open Energy Info (EERE)

Heat Discharge In The Cascade Range, Northwestern United States Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Hydrothermal Heat Discharge In...

110

Performance and Reliability of Quantum Cascade Lasers  

SciTech Connect (OSTI)

We present the burn-in behavior and power stability of multiple quantum cascade lasers (QCLs) that were measured to investigate their long-term performance. For these experiments, the current to the QCL was cycled every ten minutes, and the output power was monitored over time for durations as long as two months. A small increase in power for a given injection current is observed for almost all of the QCLs tested during the burn-in period. The data from these experiments will be presented along with the effects of packaging the QCLs to determine the impact on performance and reliability.

Myers, Tanya L.; Cannon, Bret D.; Taubman, Matthew S.; Bernacki, Bruce E.

2013-05-01T23:59:59.000Z

111

Spin Glass Computations and Ruelle's Probability Cascades  

E-Print Network [OSTI]

We study the Parisi functional, appearing in the Parisi formula for the pressure of the SK model, as a functional on Ruelle's Probability Cascades (RPC). Computation techniques for the RPC formulation of the functional are developed. They are used to derive continuity and monotonicity properties of the functional retrieving a theorem of Guerra. We also detail the connection between the Aizenman-Sims-Starr variational principle and the Parisi formula. As a final application of the techniques, we rederive the Almeida-Thouless line in the spirit of Toninelli but relying on the RPC structure.

Louis-Pierre Arguin

2006-08-17T23:59:59.000Z

112

Multiplicative cascades and seismicity in natural time  

Science Journals Connector (OSTI)

Natural time ? enables the distinction of two origins of self-similarity, i.e., the process memory and the process increments infinite variance. Employing multiplicative cascades in natural time, the most probable value of the variance ?1(???2?????2) is explicitly related with the parameter b of the Gutenberg-Richter law of randomly shuffled earthquake data. Moreover, the existence of temporal and magnitude correlations is studied in the original earthquake data. Magnitude correlations are larger for closer in time earthquakes, when the maximum interoccurrence time varies from half a day to 1 min.

N. V. Sarlis; E. S. Skordas; P. A. Varotsos

2009-08-11T23:59:59.000Z

113

Free Energy Cascade in Gyrokinetic Turbulence  

SciTech Connect (OSTI)

In gyrokinetic theory, the quadratic nonlinearity is known to play an important role in the dynamics by redistributing (in a conservative fashion) the free energy between the various active scales. In the present study, the free energy transfer is analyzed for the case of ion temperature gradient driven turbulence. It is shown that it shares many properties with the energy transfer in fluid turbulence. In particular, one finds a (strongly) local, forward (from large to small scales) cascade of free energy in the plane perpendicular to the background magnetic field. These findings shed light on some fundamental properties of plasma turbulence, and encourage the development of large-eddy-simulation techniques for gyrokinetics.

Banon Navarro, A.; Morel, P.; Albrecht-Marc, M.; Carati, D. [Universite Libre de Bruxelles, Faculte des Sciences, Physique Statistique et Plasmas CP 231, EURATOM Association, Campus Plaine, 1050 Brussels (Belgium); Merz, F.; Goerler, T.; Jenko, F. [Max-Planck-Institut fuer Plasmaphysik, EURATOM Association, 85748 Garching (Germany)

2011-02-04T23:59:59.000Z

114

Sb-free quantum cascade lasers in the 34 ?m spectral range  

Science Journals Connector (OSTI)

In this work, the design and implementation of Sb-free short wavelength strain-compensated quantum cascade lasers in the 34 ?m spectral range is presented. Due to the presence of highly strained AlAs-barrier layers, the optimization of the epitaxial growth process is firstly discussed. The used active region design is then presented together with the observed laser performance. Watt-level room temperature emission at 3.3 ?m is shown for FabryPerot devices and laser operation in pulsed mode is observed above 350 K. The laser performance is comparable with Sb-containing quantum cascade lasers. Spectral tuning of the lasers in an external cavity configuration over more than 275 cm?1 is achieved with an emission wavelength as short as 3.15 ?m. For the first time in this spectral range, results on single-mode buried heterostructure distributed feedback lasers are shown.

A Bismuto; S Riedi; B Hinkov; M Beck; J Faist

2012-01-01T23:59:59.000Z

115

Power Grid Defense Against Malicious Cascading Failure  

E-Print Network [OSTI]

An adversary looking to disrupt a power grid may look to target certain substations and sources of power generation to initiate a cascading failure that maximizes the number of customers without electricity. This is particularly an important concern when the enemy has the capability to launch cyber-attacks as practical concerns (i.e. avoiding disruption of service, presence of legacy systems, etc.) may hinder security. Hence, a defender can harden the security posture at certain power stations but may lack the time and resources to do this for the entire power grid. We model a power grid as a graph and introduce the cascading failure game in which both the defender and attacker choose a subset of power stations such as to minimize (maximize) the number of consumers having access to producers of power. We formalize problems for identifying both mixed and deterministic strategies for both players, prove complexity results under a variety of different scenarios, identify tractable cases, and develop algorithms f...

Shakarian, Paulo; Lindelauf, Roy

2014-01-01T23:59:59.000Z

116

Terahertz quantum cascade lasers based on resonant phonon scattering for depopulation  

Science Journals Connector (OSTI)

...Michael Pepper Terahertz quantum cascade lasers based on resonant phonon...development of terahertz (THz) quantum cascade lasers (QCLs), in which the depopulation...intersubband|quantum wells|quantum cascade lasers|longitudinal optical...

2004-01-01T23:59:59.000Z

117

Energy flow along the medium-induced parton cascade  

E-Print Network [OSTI]

We discuss the dynamics of parton cascades that develop in dense QCD matter, and contrast their properties with those of similar cascades of gluon radiation in vacuum. We argue that such cascades belong to two distinct classes that are characterized respectively by an increasing or a constant (or decreasing) branching rate along the cascade. In the former class, of which the BDMPS, medium-induced, cascade constitutes a typical example, it takes a finite time to transport a finite amount of energy to very soft quanta, while this time is essentially infinite in the latter case, to which the DGLAP cascade belongs. The medium induced cascade is accompanied by a constant flow of energy towards arbitrary soft modes, leading eventually to the accumulation of the initial energy of the leading particle at zero energy. It also exhibits scaling properties akin to wave turbulence. These properties do not show up in the cascade that develops in vacuum. There, the energy accumulates in the spectrum at smaller and smaller e...

Blaizot, Jean-Paul

2015-01-01T23:59:59.000Z

118

A Cascade Multilevel Inverter Using a Single DC Source  

E-Print Network [OSTI]

A Cascade Multilevel Inverter Using a Single DC Source Zhong Du1, Leon M. Tolbert2 3, John N inverter can be implemented using only a single DC power source and capacitors. A standard cascade multilevel inverter requires DC sources for 2 + 1 levels. Without requiring transformers, the scheme proposed

Tolbert, Leon M.

119

Computational Analysis of Cascading Failures in Power Networks  

E-Print Network [OSTI]

of smart grid measurement and control algorithms that can mitigate a cascade. Categories and Subject. Specifically, we consider performance metrics such as the distance between failures, the length of the cascade (under different metrics) is NP-hard. Finally, for specific graphs, we develop a fast algorithm

Shepard, Kenneth

120

Bandstructure and electronic states in terahertz quantum cascade lasers  

Science Journals Connector (OSTI)

Bandstructure and electron eigenstates in terahertz Quantum Cascade Lasers (QCLs) are studied by using the Quantum Transmitting Boundary Method (QTBM). It has several advantages compared to the commonly used Transfer Matrix Method (TMM). ... Keywords: QCL, QTBM, TMM, bandstructure, electron eigenstates, nanoscale technology, nanotechnology, quantum cascade lasers, quantum transmitting boundary methods, transfer matrix methods

Jing Tao Lu; Jun Cheng Cao

2006-06-01T23:59:59.000Z

Note: This page contains sample records for the topic "region cascades gea" 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

1st workshop on diffusion networks and cascade analytics  

Science Journals Connector (OSTI)

Diffusion and cascades have been studied for many years in sociology, and different theoretical models have been developed. However, experimental validation has been always carried out in relatively small datasets. In recent years, with the availability ... Keywords: cascade modeling, diffusion networks

Peng Cui; Fei Wang; Hanghang Tong; Manuel Gomez Rodriguez

2014-02-01T23:59:59.000Z

122

Cascade Sierra Solutions CSS | Open Energy Information  

Open Energy Info (EERE)

Sierra Solutions CSS Sierra Solutions CSS Jump to: navigation, search Name Cascade Sierra Solutions (CSS) Place Coburg, Oregon Zip 97408-1313 Product Oregon-based, non-profit organization dedicated to saving fuel and reducing emissions from heavy-duty diesel engines. Coordinates 50.263202°, 10.966202° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":50.263202,"lon":10.966202,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

123

Highly temperature insensitive quantum cascade lasers  

SciTech Connect (OSTI)

An InP based quantum cascade laser (QCL) heterostructure emitting around 5 {mu}m is grown with gas-source molecular beam epitaxy. The QCL core design takes a shallow-well approach to maximize the characteristic temperatures, T{sub 0} and T{sub 1}, for operations above room temperature. A T{sub 0} value of 383 K and a T{sub 1} value of 645 K are obtained within a temperature range of 298-373 K. In room temperature continuous wave operation, this design gives a single facet output power of 3 W and a wall plug efficiency of 16% from a device with a cavity length of 5 mm and a ridge width of 8 {mu}m.

Bai, Y.; Bandyopadhyay, N.; Tsao, S.; Selcuk, E.; Slivken, S.; Razeghi, M. [Department of Electrical Engineering and Computer Science, Center for Quantum Devices, Northwestern University, Evanston, Illinois 60208 (United States)

2010-12-20T23:59:59.000Z

124

Conserved quantities and dual turbulent cascades in Anti-de Sitter spacetime  

E-Print Network [OSTI]

We consider the dynamics of a spherically symmetric massless scalar field coupled to general relativity in Anti--de Sitter spacetime in the small-amplitude limit. Within the context of our previously developed two time framework (TTF) to study the leading self-gravitating effects, we demonstrate the existence of two new conserved quantities in addition to the known total energy $E$ of the modes: The particle number $N$ and Hamiltonian $H$ of our TTF system. $H$ represents the next-order contribution after $E$ to the total ADM mass $M$. Simultaneous conservation of $E$ and $N$ implies that weak turbulent processes undergo dual cascades (direct cascade of $E$ and inverse cascade of $N$ or vice versa). This partially explains the observed dynamics of 2-mode initial data. In addition, conservation of $E$ and $N$ limits the region of phase space that can be explored within the TTF approximation and in particular rules out equipartion of energy among the modes for general initial data. Finally, we discuss possible effects of conservation of $N$ and $E$ on late time dynamics.

Alex Buchel; Stephen R. Green; Luis Lehner; Steve L. Liebling

2014-12-15T23:59:59.000Z

125

Conserved quantities and dual turbulent cascades in Anti-de Sitter spacetime  

E-Print Network [OSTI]

We consider the dynamics of a spherically symmetric massless scalar field coupled to general relativity in Anti--de Sitter spacetime in the small-amplitude limit. Within the context of our previously developed two time framework (TTF) to study the leading self-gravitating effects, we demonstrate the existence of two new conserved quantities in addition to the known total energy $E$ of the modes: The particle number $N$ and Hamiltonian $H$ of our TTF system. Simultaneous conservation of $E$ and $N$ implies that weak turbulent processes undergo dual cascades (direct cascade of $E$ and inverse cascade of $N$ or vice versa). This partially explains the observed dynamics of 2-mode initial data. In addition, conservation of $E$ and $N$ limits the region of phase space that can be explored within the TTF approximation and in particular rules out equipartion of energy among the modes for general initial data. Finally, we discuss possible effects of conservation of $N$ and $E$ on late time dynamics.

Alex Buchel; Stephen R. Green; Luis Lehner; Steven L. Liebling

2015-02-17T23:59:59.000Z

126

Cascade Natural Gas - Conservation Incentives for New Homes | Department of  

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

Cascade Natural Gas - Conservation Incentives for New Homes Cascade Natural Gas - Conservation Incentives for New Homes Cascade Natural Gas - Conservation Incentives for New Homes < Back Eligibility Residential Savings Category Home Weatherization Commercial Weatherization Heating & Cooling Construction Commercial Heating & Cooling Design & Remodeling Sealing Your Home Ventilation Heating Appliances & Electronics Water Heating Program Info State District of Columbia Program Type Utility Rebate Program Rebate Amount High Efficiency Natural Gas Furnace: $150 High Efficiency Natural Gas Hearth: $70 Conventional Natural Gas Water Heater: $40 Condensing Tankless Water Heater: $200 Combined Domestic Water/Hydronic Space Heating System (usingTankless Water Heater): $800 Energy Star Certified Home: $350 Energy Star Certified Plus Home: $750

127

Superconvergence of period doubling cascade in trapezoid maps  

E-Print Network [OSTI]

In the symmetric and the asymmetric trapezoid maps, as a slope of the trapezoid is increased, the period doubling cascade occurs and the symbolic sequence of periodic points is the Metropolis-Stein-Stein sequence and the convergence of the onset point of the period 2^m solution to the accumulation point is exponentially fast. We reported these results previously. In this paper, we give the detailed description of the proof on the results. Further, we study the period doubling cascade starting from period p solution and show the superconvergence of the period doubling cascade.

T. Uezu

2000-01-12T23:59:59.000Z

128

Design and preliminary testing of a thermionic AMTEC cascade  

SciTech Connect (OSTI)

This paper describes the design of an experiment to demonstrate the feasibly of operating a cascade of a Thermionic Energy Converter (TEC) with an Alkali Metal Thermo Electric Converter (AMTEC). Both of these devices convert heat to electricity without moving mechanical parts and lend themselves to be incorporated into a cascade. Typically, the TEC operates from a hot temperature of 2000 K to 1700 K, rejecting heat at 1100 K to 700 K, while the AMTEC operates from a hot temperature of 1100 K to 900 K and a cold temperature of about 400 K. These temperature ranges form almost ideal cascade. {copyright} {ital 1996 American Institute of Physics.}

Miskolczy, G. [Thermo Trex Corp., 85 First Avenue, Waltham, Massachusetts 02254 (United States); Sievers, B.; Svedberg, B. [Advanced Modular Power Systems, Inc., 4667 Freedom Drive, Ann Arbor, Michigan 48108 (United States); Schuller, M. [Phillips Laboratory/VTPN, Kirtland Air Force Base, New Mexico 87117 (United States); VanHagen, T.; Smith, J. [General Atomics, 3550 General Atomics Court, San Diego, California 92121-1194 (United States); Reiners, E.; LeMire, R. [ORION International Technologies, Inc., 6501 Americas Parkway NE, Suite 200, Albuquerque, New Mexico 87110 (United States)

1996-03-01T23:59:59.000Z

129

High-resolution emission spectra of pulsed terahertz quantum-cascade lasers  

SciTech Connect (OSTI)

The spectra of pulsed terahertz quantum-cascade lasers were measured with high spectral resolution. The characteristic line width at half maximum was 0.01 cm{sup -1}; it is controlled by laser temperature variations during the supply voltage pulse. It was shown that an increase in the laser temperature leads to a decrease in the emission frequency, which is caused by an increase in the effective refractive index of the active region. It was also found that a decrease in the supply voltage results in a decrease in the emission frequency, which is caused by a change in the energy of diagonal transitions between lasing levels.

Ikonnikov, A. V., E-mail: antikon@ipm.sci-nnov.ru; Antonov, A. V.; Lastovkin, A. A.; Gavrilenko, V. I. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation); Sadof'ev, Yu. G.; Samal, N. [Trion Technology (United States)

2010-11-15T23:59:59.000Z

130

Angular correlation of K-L x-ray cascades in gadolinium  

Science Journals Connector (OSTI)

Angular correlation parameters (A22) between the K?1 and L3 x rays were measured for gadolinium in the electron-capture decay of the isotope Tb157. The results are A22(K?1-Ll)=0.2720.042, A22(K?1-L?)=0.0320.015, A22(K?1-L?2,15)=0.0610.018. These values are in very good agreement with the theoretical calculations of Scofield [Lawrence Livermore Laboratory Report No. UCRL 51231, 1972 (unpublished)]; however, they differ from the earlier experimental data for the K?1-Ll cascade in the 60region.

T. Papp, J. L. Campbell, and S. Raman

1994-02-01T23:59:59.000Z

131

EA-1893: Canby Cascaded Geothermal Development System, Canby, California |  

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

93: Canby Cascaded Geothermal Development System, Canby, 93: Canby Cascaded Geothermal Development System, Canby, California EA-1893: Canby Cascaded Geothermal Development System, Canby, California Summary This EA will evaluate the environmental impacts of a proposal by Modoc Contracting Company to use DOE grant funds to fulfill its plan to expand its reliance on geothermal resources by producing more hot water and using it to produce power as well as thermal energy. The goal of the project is to complete a cascaded geothermal system that generates green power for the local community, provides thermal energy to support greenhouse and aquaculture operation, provide sustainable thermal energy for residential units, and eliminate the existing geothermal discharge to a local river. NOTE: NOTE: This EA has been cancelled.

132

MHK Technologies/Oscillating Cascade Power System OCPS | Open Energy  

Open Energy Info (EERE)

Oscillating Cascade Power System OCPS Oscillating Cascade Power System OCPS < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage Oscillating Cascade Power System OCPS.jpg Technology Profile Primary Organization New Energy Solutions LLC Technology Resource Click here Current Technology Type Click here Oscillating Wave Surge Converter Technology Readiness Level Click here TRL 5 6 System Integration and Technology Laboratory Demonstration Technology Description The OCPS generator consists of a cascade of vertical hydrofoils submerged in moving water This array of hydrofoils oscillates in antiphase at resonance flutter in a slow swimming motion resulting in maximum power transfer from flowing water to electricity The system efficiently converts the oscillating mechanical energy into a steady electric current A 60 overall water to wire efficiency was demonstrated at the proof of concept test and 65 or better overall efficiency is projected using the new engineering advances incorporated since the test in the commercial model

133

Statistical analysis of cascading failures in power grids  

SciTech Connect (OSTI)

We introduce a new microscopic model of cascading failures in transmission power grids. This model accounts for automatic response of the grid to load fluctuations that take place on the scale of minutes, when optimum power flow adjustments and load shedding controls are unavailable. We describe extreme events, caused by load fluctuations, which cause cascading failures of loads, generators and lines. Our model is quasi-static in the causal, discrete time and sequential resolution of individual failures. The model, in its simplest realization based on the Directed Current description of the power flow problem, is tested on three standard IEEE systems consisting of 30, 39 and 118 buses. Our statistical analysis suggests a straightforward classification of cascading and islanding phases in terms of the ratios between average number of removed loads, generators and links. The analysis also demonstrates sensitivity to variations in line capacities. Future research challenges in modeling and control of cascading outages over real-world power networks are discussed.

Chertkov, Michael [Los Alamos National Laboratory; Pfitzner, Rene [Los Alamos National Laboratory; Turitsyn, Konstantin [Los Alamos National Laboratory

2010-12-01T23:59:59.000Z

134

Characterization of mid-infrared quantum cascade lasers  

E-Print Network [OSTI]

Quantum cascade lasers provide some of the highest output powers available for light in the mid-infrared range (from 3 to 8 m). As many of their applications require portability, designs that have a high wall-plug efficiency ...

Burghoff, David Patrick

2009-01-01T23:59:59.000Z

135

Cascading Goals and Objectives to Ensure Accountability and Action  

E-Print Network [OSTI]

Bristol-Myers Squibb Worldwide Beauty Care Group has adopted a methodology that is reaping benefits throughout the company. The underlying principle in cascading goals and objectives is that every employee is accountable for achieving any corporate...

Tarifi, M.; Bingham, P. R.

136

Theoretical and computational design of terahertz frequency quantum cascade lasers  

Science Journals Connector (OSTI)

Modeling of terahertz frequency quantum cascade lasers has become increasingly complex theoretically resulting in burdensome computational requirements. While more comprehensive treatment permits further insight and increased accuracy the modeling of ...

Adam T. Cooney / A.M. Sarangan

2009-01-01T23:59:59.000Z

137

Spectroscopic detection of biological NO with a quantum cascade laser  

Science Journals Connector (OSTI)

Two configurations of a continuous wave quantum cascade distributed feedback laser-based gas sensor for the detection of ... of biomedical applications, have been investigated. The laser was operated at liquid ni...

L. Menzel; A.A. Kosterev; R.F. Curl; F.K. Tittel; C. Gmachl

2001-05-01T23:59:59.000Z

138

Open-path ozone detection by quantum-cascade laser  

Science Journals Connector (OSTI)

Open-path ozone measurements performed by mid-IR differential absorption spectroscopy are reported. Ozone spectrum was taken by fast repetitive sweeping of a quantum-cascade laser wavelength over a spectral featu...

M. Taslakov; V. Simeonov; M. Froidevaux; H. van den Bergh

2006-03-01T23:59:59.000Z

139

Mathematical modeling for a thermionic-AMTEC cascade system  

SciTech Connect (OSTI)

A mathematical modeling of a system consisting of a cascade of a thermionic energy conversion (TIEC) device and an alkali metal thermal to electrical conversion (AMTEC) device has been performed. The TIEC is heated by electron bombardment which converts heat partially into electricity and rejects the remaining. The AMTEC utilizes this reject heat of the TIEC. A mathematical thermal model of the cascade converter has been developed to analyze effects of key parameters such as power level, heat fluxes, temperatures, cascade geometry, etc. In this effort, a 9-node system of nonlinear simultaneous equations has been constructed which is solved by MATHCAD predicting the temperatures of the principal components and the heat flow. Through this study, a better understanding of the thermal coupling of the two converters was gained which helps to produce a more efficient cascade. {copyright} {ital 1996 American Institute of Physics.}

Lodhi, M.A. [Department of Physics, Texas Tech University, Lubbock, Texas 79409 (United States); Schuller, M.; Hausgen, P. [Phillips Laboratory, Kirtland AFB, New Mexico 87117 (United States)

1996-03-01T23:59:59.000Z

140

Characterization and analysis of highly diagonal Terahertz Quantum Cascade Lasers  

E-Print Network [OSTI]

The as yet unattained milestone of room-temperature operation is essential for establishing Terahertz Quantum Cascade Lasers (THz QCLs) as practical sources of THz radiation. Temperature performance is hypothesized to be ...

Chan, Chun Wang Ivan

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "region cascades gea" 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

Heat flux dynamics in dissipative cascaded systems  

E-Print Network [OSTI]

We study the dynamics of heat flux in the thermalization process of a pair of identical quantum system that interact dissipatively with a reservoir in a {\\it cascaded} fashion. Despite the open dynamics of the bipartite system S is globally Lindbladian, one of the subsystems "sees" the reservoir in a state modified by the interaction with the other subsystem and hence it undergoes a non-Markovian dynamics. As a consequence, the heat flow exhibits a non-exponential time behaviour which can greatly deviate from the case where each party is independently coupled to the reservoir. We investigate both thermal and correlated initial states of $S$ and show that the presence of correlations at the beginning can considerably affect the heat flux rate. We carry out our study in two paradigmatic cases -- a pair of harmonic oscillators with a reservoir of bosonic modes and two qubits with a reservoir of fermionic modes -- and compare the corresponding behaviours. In the case of qubits and for initial thermal states, we find that the trace distance discord is at any time interpretable as the correlated contribution to the total heat flux.

Salvatore Lorenzo; Alessandro Farace; Francesco Ciccarello; G. Massimo Palma; Vittorio Giovannetti

2014-12-19T23:59:59.000Z

142

The Cascaded Humidified Advanced Turbine (CHAT)  

SciTech Connect (OSTI)

This paper introduces the Cascaded Humidified Advanced Turbine (CHAT) plant, a gas turbine based power generation plant utilizing intercooling, reheat, and humidification. It is based upon the integration of an existing heavy duty gas turbine with an additional shaft comprising industrial compressors and high pressure expander. CHAT capitalizes on the latest proven gas turbine technology, which, combined with a sophisticated thermal cycle configuration, results in substantial improvement in gas turbine efficiency, compared to a simple cycle, while still maintaining typical advantages and merits of a combustion turbine plant. Built with a commercial combustion turbine and available industrial compressors and expanders, the CHAT plant does not require extensive product development and testing. As a result, the CHAT power plant can be offered with specific capital costs up to 20 percent lower than the combined cycle plant, and with competing efficiency. Compared to a combined cycle plant, the CHAT plant offers lower emissions (due to air humidification) and other significant operating advantages with regard to start-up time and costs, better efficiency at part load, lower power degradation at higher ambient temperatures, and simpler operations and maintenance due to elimination of the complexities and costs associated with steam production. The CHAT plant also integrates very effectively with coal gasification and particularly well with the water quench design. This feature has been discussed in previous publications.

Nakhamkin, M.; Swensen, E.C. [Energy Storage and Power Consultants, Inc., Mountainside, NJ (United States); Wilson, J.M.; Gaul, G. [Westinghouse Electric Corp., Orlando, FL (United States); Polsky, M. [Polsky Energy Corp., Northbrook, IL (United States)

1996-07-01T23:59:59.000Z

143

Proton heating by parallel Alfven wave cascade  

SciTech Connect (OSTI)

In a recent series of papers, the present authors developed a kinetic theory for low-frequency turbulence propagating parallel to the ambient magnetic field. Making use of this theory, it was shown that low-frequency Alfvenic turbulence may cascade to ion-cyclotron frequency range and beyond by nonlinear three-wave decay processes. The significance of such a finding is that it may lead to the proton heating by cyclotron resonance. However, the actual proton heating process was not demonstrated. The present paper complements the previous works by including the proton heating in the discussion. It is found that the left-hand circularly polarized Alfven-cyclotron turbulence leads to a moderate heating of the protons in the perpendicular direction and cooling in the parallel direction. It is also found that ion-acoustic turbulence is generated by the decay instability process. Finally, the heating rate is shown to increase in inverse proportion to the time scale of the wave source.

Yoon, P. H.; Fang, T.-M. [Massachusetts Technological Laboratory, Inc., 330 Pleasant Street, Belmont, Massachusetts 02478 (United States)

2009-06-15T23:59:59.000Z

144

Poincare recurrence and spectral cascades in three-dimensional quantum turbulence  

SciTech Connect (OSTI)

The time evolution of the ground state wave function of a zero-temperature Bose-Einstein condensate (BEC) gas is well described by the Hamiltonian Gross-Pitaevskii (GP) equation. Using a set of appropriately interleaved unitary collision-stream operators, a qubit lattice gas algorithm is devised, which on taking moments, recovers the Gross-Pitaevskii (GP) equation under diffusion ordering (time scales as length{sup 2}). Unexpectedly, there is a class of initial states whose Poincare recurrence time is extremely short and which, as the grid resolution is increased, scales with diffusion ordering (and not as length{sup 3}). The spectral results of J. Yepez et al.[Phys. Rev. Lett. 103, 084501 (2009).] for quantum turbulence are revised and it is found that it is the compressible kinetic energy spectrum that exhibits three distinct spectral regions: a small-k classical-like Kolmogorov k{sup -5/3}, a steep semiclassical cascade region, and a large-k quantum vortex spectrum k{sup -3}. For most evolution times the incompressible kinetic energy spectrum exhibits a somewhat robust quantum vortex spectrum of k{sup -3} for an extended range in k with a k{sup -3.4} spectrum for intermediate k. For linear vortices of winding number 1 there is an intermittent loss of the quantum vortex cascade with its signature seen in the time evolution of the kinetic energy E{sub kin}(t), the loss of the quantum vortex k{sup -3} spectrum in the incompressible kinetic energy spectrum as well as the minimalization of the vortex core isosurfaces that would totally inhibit any Kelvin wave vortex cascade. In the time intervals around these intermittencies the incompressible kinetic energy also exhibits a multicascade spectrum.

Vahala, George; Zhang Bo [Department of Physics, William and Mary, Williamsburg, Virginia 23185 (United States); Yepez, Jeffrey [Air Force Research Laboratory, Hanscom Air Force Base, Massachusetts 01731 (United States); Vahala, Linda [Department of Electrical and Computer Engineering, Old Dominion University, Norfolk, Virginia 23529 (United States); Soe, Min [Department of Mathematics and Physical Sciences, Rogers State University, Claremore, Oklahoma 74017 (United States); Ziegeler, Sean [High Performance Technologies, Inc., Reston, Virginia 20190 (United States)

2011-10-15T23:59:59.000Z

145

Aeration efficiency over stepped cascades: Better predictions from flow regimes  

Science Journals Connector (OSTI)

Abstract Stepped cascades are recognized as high potential airwater gas exchangers. In natural rivers, these structures enhance oxygen transfer to water by creating turbulence at interface with increasing air entrainment in water and airwater surface exchange. Stepped cascades could be really useful to improve the natural self-purification process by providing oxygen to aerobic micro-organisms. The aeration performance of these structures depends on several operating and geometrical parameters. In the literature, several empirical correlations for aeration efficiency prediction on stepped cascades exist. Most of these correlations are only applicable for operating and geometrical parameters in the range of which they have been developed. In this paper, 398 experimental sets of data (from our experiments and collected from literature) were used to develop a correlation for aeration prediction over stepped cascades derived from dimensional analysis and parameterized for each individual flow regime in order to consider change in flow regime effect on oxygen transfer. This new correlation allowed calculating the whole set of data obtained for cascades with steps heights between 0.05m and 0.254m, cascade total height between 0.25m and 2.5m, for discharges per unit of width ranging from 0.28 10?3m2/s to 600 10?3m2/s and for cascade steps number between 3 and 25. In these ranges of parameters, standard deviation for aeration efficiency estimation was found to be less than 17%. Finally, advices were proposed to help and improve the structure design in order to improve aeration.

Hatem Khdhiri; Olivier Potier; Jean-Pierre Leclerc

2014-01-01T23:59:59.000Z

146

MATCASC: A tool to analyse cascading line outages in power grids  

E-Print Network [OSTI]

Blackouts in power grids typically result from cascading failures. The key importance of the electric power grid to society encourages further research into sustaining power system reliability and developing new methods to manage the risks of cascading blackouts. Adequate software tools are required to better analyze, understand, and assess the consequences of the cascading failures. This paper presents MATCASC, an open source MATLAB based tool to analyse cascading failures in power grids. Cascading effects due to line overload outages are considered. The applicability of the MATCASC tool is demonstrated by assessing the robustness of IEEE test systems and real-world power grids with respect to cascading failures.

Ko, Yakup; Araujo, Nuno A M; Warnier, Martijn

2013-01-01T23:59:59.000Z

147

Canby Cascaded Project Geothermal Project | Open Energy Information  

Open Energy Info (EERE)

Canby Cascaded Project Geothermal Project Canby Cascaded Project Geothermal Project Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Development Project: Canby Cascaded Project Geothermal Project Project Location Information Coordinates 41.443888888889°, -120.87027777778° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":41.443888888889,"lon":-120.87027777778,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

148

Cascade Natural Gas - Commercial Efficiency Rebate Program | Department of  

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

Cascade Natural Gas - Commercial Efficiency Rebate Program Cascade Natural Gas - Commercial Efficiency Rebate Program Cascade Natural Gas - Commercial Efficiency Rebate Program < Back Eligibility Commercial Industrial Savings Category Heating & Cooling Commercial Heating & Cooling Heating Home Weatherization Commercial Weatherization Appliances & Electronics Sealing Your Home Design & Remodeling Windows, Doors, & Skylights Water Heating Program Info State District of Columbia Program Type Utility Rebate Program Rebate Amount HVAC Unit Heater: $1.50-$3 / kBtuh input Warm Air Furnace: $3.00 / kBtuh input Direct Fired Radiant Heating: $6.50 / kBtuh input Boiler: $4.00 / kBtuh input Boiler Vent Damper: $1,000 Boiler Steam Trap: $80 DHW Energy Star Tankless Water Heaters: $60 / gpm Domestic Hot Water Tank: $2.50 / kBtuh input

149

Recent results from parton cascade and microscopic transport  

E-Print Network [OSTI]

Parton cascade is a microscopic transport approach for the study of the space-time evolution of the Quark-Gluon Plasma produced in relativistic heavy ion collisions and its experimental manifestations. In the following, parton cascade calculations on elliptic flow and thermalization will be discussed. Dynamical evolution is shown to be important for the production of elliptic flow including the scaling and the breaking of the scaling of elliptic flow. The degree of thermalization is estimated using both an elastic parton cascade and a radiative transport model. A longitudinal to transverse pressure ratio, $P_L/P_T\\approx 0.8$, is shown to be expected in the central cell in central collisions. This provides information on viscous corrections to the ideal hydrodynamical approach.

Bin Zhang

2008-09-02T23:59:59.000Z

150

Reducing Cascading Failure Risk by Increasing Infrastructure Network Interdependency  

E-Print Network [OSTI]

Increased coupling between critical infrastructure networks, such as power and communications, has important implications for the reliability and security of these networks. To understand the implications of power-communications coupling, researchers have studied interdependent network models and reported that increased coupling can increase system vulnerability [1, 2]. However, these results come from models that have substantially different mechanisms of cascading, relative to those found in actual power and communications networks. This paper reports on two sets of experiments that compare the network vulnerability implications resulting from simple topological models and models that more accurately capture the dynamics of cascading in power systems. In the first set of experiments, we compare a simple model of intra-network cascading to a power grid model and find that the power grid model reveals that power grids have a higher level of vulnerability, relative to what would be inferred from a topological ...

Korkali, Mert; Tivnan, Brian F; Hines, Paul D H

2014-01-01T23:59:59.000Z

151

Role of second trials in cascades of information over networks  

Science Journals Connector (OSTI)

We study the propagation of information in social networks. To do so, we focus on a cascade model where nodes are infected with probability p1 after their first contact with the information and with probability p2 at all subsequent contacts. The diffusion starts from one random node and leads to a cascade of infection. It is shown that first and subsequent trials play different roles in the propagation and that the size of the cascade depends in a nontrivial way on p1, p2, and on the network structure. Second trials are shown to amplify the propagation in dense parts of the network while first trials are dominant for the exploration of new parts of the network and launching new seeds of infection.

C. de Kerchove; G. Krings; R. Lambiotte; P. Van Dooren; V. D. Blondel

2009-01-30T23:59:59.000Z

152

On the Origin of Large Interstitial Clusters in Displacement Cascades  

SciTech Connect (OSTI)

Displacement cascades with wide ranges of primary knock-on atom (PKA) energy and mass in iron were simulated using molecular dynamics. New visualisation techniques are introduced to show how the shock-front dynamics and internal structure of a cascade develop over time. These reveal that the nature of the final damage is determined early on in the cascade process. We define a zone (termed 'spaghetti') in which atoms are moved to new lattice sites and show how it is created by a supersonic shock-front expanding from the primary recoil event. A large cluster of self-interstitial atoms can form on the periphery of the spaghetti if a hypersonic recoil creates damage with a supersonic shock ahead of the main supersonic front. When the two fronts meet, the main one injects atoms into the low-density core of the other: these become interstitial atoms during the rapid recovery of the surrounding crystal. The hypersonic recoil occurs in less than 0.1 ps after the primary recoil and the interstitial cluster is formed before the onset of the thermal spike phase of the cascade process. The corresponding number of vacancies is then formed in the spaghetti core as the crystal cools, i.e. at times one to two orders of magnitude longer. By using the spaghetti zone to define cascade volume, the energy density of a cascade is shown to be almost independent of the PKA mass. This throws into doubt the conventional energy-density interpretation of an increased defect yield with increasing PKA mass in ion irradiation.

Andrew, Calder F [University of Liverpool; Barashev, Aleksandr [University of Liverpool; Bacon, David J [University of Liverpool; Osetskiy, Yury N [ORNL

2010-01-01T23:59:59.000Z

153

Atomic Cascade in Muonic and Hadronic Hydrogen Atoms  

E-Print Network [OSTI]

The atomic cascade in $\\mu^- p$ and $\\pi^- p$ atoms has been studied with the improved version of the extended cascade model in which new quantum mechanical calculations of the differential and integral cross sections of the elastic scattering, Stark transitions and Coulomb de-excitation have been included for the principal quantum number values $n\\le 8$ and the relative energies $E \\ge 0.01$ eV. The $X$-ray yields and kinetic energy distributions are compared with the experimental data.

T. S. Jensen; V. P. Popov; V. N. Pomerantsev

2007-12-18T23:59:59.000Z

154

Ultrafast population dynamics in electrically modulated terahertz quantum cascade lasers  

Science Journals Connector (OSTI)

The ultrafast population dynamics in electrically modulated three-well terahertz quantum cascade lasers (QCLs) is studied by using the self-consistent BlochPoisson equations. In the modulation process, the non-equilibrium oscillations of the population inversion are found before the population equilibrium recovers. The equilibrium formation time increases nonlinearly with the period number. This phenomenon stems from the non-uniform distribution of the electric potential. In different periods, different responses to the electrical modulation are also explored. An in-depth understanding of electron transport in the cascade structure is obtained. Finally, we demonstrate the feasibility of a modulation frequency up to gigahertz in terahertz QCLs.

F Wang; X G Guo; C Wang; J C Cao

2013-01-01T23:59:59.000Z

155

Rapid Cascade Synthesis of Poly-Heterocyclic Architectures from Indigo  

Science Journals Connector (OSTI)

Bubbling CO2 gas through a standard reaction (entry 3) resulted in a 6% yield of 8, however, the most significant outcome from this reaction is the notably reduced yields of 4, 5, 6, and 7, and a dramatic increase in the production of noncharacterizable baseline material. ... There have been reported syntheses of these natural products including the silver-catalyzed cascade synthesis of their parent compound and analogs, with this approach involving the initial intermolecular reaction of two components of similar molecular complexity, however, this necessitated the prior synthesis of these two components. ... Branching Cascades: A Concise Synthetic Strategy Targeting Diverse and Complex Molecular Frameworks ...

Alireza Shakoori; John B. Bremner; Anthony C. Willis; Rachada Haritakun; Paul A. Keller

2013-06-26T23:59:59.000Z

156

Seed size strongly affects cascades on random networks  

Science Journals Connector (OSTI)

The average avalanche size in the Watts model of threshold dynamics on random networks of arbitrary degree distribution is determined analytically. Existence criteria for global cascades are shown to depend sensitively on the size of the initial seed disturbance. The dependence of cascade size upon the mean degree z of the network is known to exhibit several transitionsthese are typically continuous at low z and discontinuous at high z; here it is demonstrated that the low-z transition may in fact be discontinuous in certain parameter regimes. Connections between these results and the zero-temperature random-field Ising model on random graphs are discussed.

James P. Gleeson and Diarmuid J. Cahalane

2007-05-03T23:59:59.000Z

157

E-Print Network 3.0 - atmospheric neutrino-induced cascades Sample...  

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

Fly's Eye Project Collection: Physics 6 SEARCH FOR NEUTRINO-INDUCED CASCADES FROM GAMMA-RAY BURSTS WITH AMANDA A. Achterberg,1 Summary: SEARCH FOR NEUTRINO-INDUCED CASCADES FROM...

158

Rhodium-catalyzed epoxide-opening cascades toward brevisin and hemibrevetoxin B  

E-Print Network [OSTI]

CHAPTER I. Rhodium-Catalyzed Epoxide-Opening Cascades: Formal Synthesis of (-)-Brevisin [chemical formula inserted] [Rh(CO)?Cl]? was found to be an effective catalyst for endo-selective cyclizations and cascades of ...

Armbrust, Kurt W. (Kurt Willes)

2014-01-01T23:59:59.000Z

159

Cascaded H-Bridge MV Grid and Power Balance Control for PV Systems  

Science Journals Connector (OSTI)

In this paper, a new centralized cascaded H-bridge medium-voltage (MV) grid topology model ... array partial shading or module mismatch of Cascaded H-Bridge is analyzed as well, based on which ... quality, solves...

Bin Zhang; Zhiyun Bao; Donglai Zhang

2014-01-01T23:59:59.000Z

160

Quantum Cascade Lasers: New Resonant Tunnelling Light Sources for the Mid-Infrared  

Science Journals Connector (OSTI)

15 October 1996 research-article Quantum Cascade Lasers: New Resonant Tunnelling Light Sources...Hutchinson A. Y. Cho Recent results on quantum cascade lasers are reviewed. In these quantum devices based on resonant tunnelling the...

1996-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "region cascades gea" 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

APPLYING CASCADED PARAMETER SCAN TO STUDY TOP-OFF SAFETY IN NSLS-II STORAGE RING  

SciTech Connect (OSTI)

In this paper we introduce a new algorithm, the cascaded parameter scan method, to efficiently carry out the scan over magnet parameters in the safety analysis for storage ring top-off injection. In top-off safety analysis, one must track particles populating phase space through a beamline containing magnets and apertures and clearly demonstrate that for all possible magnet settings and errors, all particles are lost on scrapers within the properly shielded region. In the usual approach, the number of tracking runs increases exponentially with the number of magnet settings. In the cascaded parameter scan method, the number of tracking runs only increases linearly. This reduction of exponential to linear dependence on the number of set-points, greatly reduces the required computation time and allows one to more densely populate phase space and to increase the number of set-points scanned for each magnet. An example of applying this approach to analyze an NSLS-II beamline, the damping wiggler beamline, is also given.

Li, Y.

2011-03-28T23:59:59.000Z

162

Shear Viscosity to Entropy within a Parton Cascade  

E-Print Network [OSTI]

The shear viscosity is calculated by means of the perturbative kinetic partonic cascade BAMPS with CGC initial conditons for various saturation momentum scale Q_s. eta/s ~ 0.15 stays approximately constant when going from RHIC to LHC.

A. El; C. Greiner; Z. Xu

2007-06-28T23:59:59.000Z

163

Hybrid Cascaded Multilevel Inverter with PWM Control Method  

E-Print Network [OSTI]

162 Hybrid Cascaded Multilevel Inverter with PWM Control Method Haiwen Liu1 , Leon M. Tolbert1, 2 inverter with PWM method is presented in this paper. It consists of a standard 3-leg inverter (one leg for each phase) and H-bridge in series with each inverter leg. It can use only a single DC power source

Tolbert, Leon M.

164

Monitoring of ethylene by a pulsed quantum cascade laser  

E-Print Network [OSTI]

Monitoring of ethylene by a pulsed quantum cascade laser Damien Weidmann, Anatoliy A. Kosterev ethylene C2H4 concentrations by use of a rotational component of the fundamental 7 band. The laser.5960, 300.6320. 1. Introduction The detection of ethylene C2H4 at trace levels is important in a number

165

Superconducting cascade electron refrigerator M. Camarasa-Gomez,1  

E-Print Network [OSTI]

arranged in a symmetric configuration, i.e. S2IS1INIS1IS2, as displayed in Fig. 1(a). The structure) S2IS1 INIS1 IS2 cascade cooler geometry. The optional el- ements contained into the two dashed boxes

Paris-Sud XI, Université de

166

Unraveling the Mechanism of Cascade Reactions of Zincke Aldehydes  

Science Journals Connector (OSTI)

Unraveling the Mechanism of Cascade Reactions of Zincke Aldehydes ... Department of Chemistry, University of California, Irvine, 1102 Natural Sciences II, Irvine, California 92697-2025, United States ... The E/Z conformational preferences (gas phase and soln.), rotational barriers, and IR spectra of ?-oxo ketenes are also reported. ...

Robert S. Paton; Sarah E. Steinhardt; Christopher D. Vanderwal; K. N. Houk

2011-02-25T23:59:59.000Z

167

Optimizing protections against cascades in network systems: a modified binary  

E-Print Network [OSTI]

to the topology of an electricity infrastructure, i.e. the 380 kV Italian power transmission network. We only protection; line switching; cascading failure; differential evolution algorithm; multi-objective optimization protection (NP) by line switching, done automatically or by a system operator, following an attack

Paris-Sud XI, Université de

168

Cascade-induced synchrony in stochastically driven neuronal networks  

Science Journals Connector (OSTI)

Perfect spike-to-spike synchrony is studied in all-to-all coupled networks of identical excitatory, current-based, integrate-and-fire neurons with delta-impulse coupling currents and Poisson spike-train external drive. This synchrony is induced by repeated cascading total firing events, during which all neurons fire at once. In this regime, the network exhibits nearly periodic dynamics, switching between an effectively uncoupled state and a cascade-coupled total firing state. The probability of cascading total firing events occurring in the network is computed through a combinatorial analysis conditioned upon the random time when the first neuron fires and using the probability distribution of the subthreshold membrane potentials for the remaining neurons in the network. The probability distribution of the former is found from a first-passage-time problem described by a Fokker-Planck equation, which is solved analytically via an eigenfunction expansion. The latter is found using a central limit argument via a calculation of the cumulants of a single neuronal voltage. The influence of additional physiological effects that hinder or eliminate cascade-induced synchrony are also investigated. Conditions for the validity of the approximations made in the analytical derivations are discussed and verified via direct numerical simulations.

Katherine A. Newhall; Gregor Kova?i?; Peter R. Kramer; David Cai

2010-10-01T23:59:59.000Z

169

Optimal adaptive control of cascading power grid failures1 Version 2010-Dec-20  

E-Print Network [OSTI]

Optimal adaptive control of cascading power grid failures1 Version 2010-Dec-20 Daniel Bienstock Columbia University New York 1 Introduction Power grids have long been a source of interesting optimization, the central modeling ingredient is that power grids display cascading behavior. A cascade is the process

Bienstock, Daniel

170

Capacitor Voltage Control in a Cascaded Multilevel Inverter as a Static Var Generator  

E-Print Network [OSTI]

1 Capacitor Voltage Control in a Cascaded Multilevel Inverter as a Static Var Generator M. Li, J. N for a cascaded multilevel inverter to be used for static var compensation. Index Terms-- Multilevel Inverter, Static Var Generator (SVG), Cascade inverter. I. INTRODUCTION Multilevel inverters have gained much

Tolbert, Leon M.

171

HARMONIC CASCADE FEL DESIGNS FOR LUX, A FACILTY FOR ULTRAFAST X-RAY SCIENCE  

E-Print Network [OSTI]

-electron laser (FEL) beamlines which use the har- monic cascade approach to produce coherent XUV & soft X-ray for an integrated system of ultrafast x-ray techniques and lasers, using laser-seeded harmonic cascade FEL's, rfHARMONIC CASCADE FEL DESIGNS FOR LUX, A FACILTY FOR ULTRAFAST X-RAY SCIENCE J. Corlett, W. Fawley

Wurtele, Jonathan

172

Activation of the cyclic AMP cascade as an ocoggenic mechanism: The thyroid example  

Science Journals Connector (OSTI)

Three cascades activate thyroid cell proliferation: the EGF-protein tyrosine kinase pathway, the phorbol ester-protein kinase C pathway and the thyrotropin-cyclic AMP pathway. While the first cascades converge early, they remain distinct from the cyclic AMP cascade until very late in G1. The cyclic AMP cascade us characterized by an early and transient expression of c-myc, which may explain why it induces proliferation and differentiation expression. Constitutive activation of this cascade causes growth and hyperfunction, ie, hyperfunctioning adenomas. The various possible defects that could lead to such a constitutive activation are discussed.

C. Maenhaut; P.P. Roger; S. Reuse; J.E. Dumont

1991-01-01T23:59:59.000Z

173

Cascade and breakdown in scale-free networks with community structure  

Science Journals Connector (OSTI)

The cascade failures in scale-free networks with community structure are studied and cascade propagation of such networks with different modularity parameters is simulated. It is found that the network with small modularity is much easier to trigger cascade failures than that of the larger one. Furthermore, different removal strategies have some what large effects on the cascade failures aftereffect. The simulations also show that larger modularity and reserve capacity coefficient will delay the breakdown caused by a cascade of network. This is particularly important for such real networks with community as traffic networks, distribution networks, and electrical power grids.

Jian-jun Wu; Zi-you Gao; Hui-jun Sun

2006-12-19T23:59:59.000Z

174

Nanobulges on surface of silicon film and SiYb quantum cascade laser  

Science Journals Connector (OSTI)

Abstract Nanosilicon provides pumping levels and the localized states produced from SiYb bond on bulge surface of silicon film generate stimulated emission, in which a four-level system is built for chip-laser. The SiYb nanobulges on Si film cause a remarkable increase of the surface area and make a buffering layer for mismatch between Si and Yb lattices. Dynamics of photoluminescence and electroluminescence on nanosilicon coated by Yb is investigated. Stimulated peaks near 700nm are observed on silicon quantum dots coated by Yb. Enhanced EL peaks in the wavelength region from 1300nm to 1650nm are measured on the Si film coated by Yb. SiYb quantum cascade laser is designed, in which emission wavelength could be manipulated into the window of optical communication by SiYb bonding on bulge surface of Si film.

Wei-Qi Huang; Shirong Liu; Zhong-Mei Huang; Xin-Jian Miao; Chao-Jian Qin; Quan Lv

2014-01-01T23:59:59.000Z

175

Cascade-Chipita Park, Colorado: Energy Resources | Open Energy Information  

Open Energy Info (EERE)

Cascade-Chipita Park, Colorado: Energy Resources Cascade-Chipita Park, Colorado: Energy Resources Jump to: navigation, search Equivalent URI DBpedia Coordinates 38.9498727°, -105.0031457° Loading map... {"minzoom":false,"mappingservice":"googlemaps3","type":"ROADMAP","zoom":14,"types":["ROADMAP","SATELLITE","HYBRID","TERRAIN"],"geoservice":"google","maxzoom":false,"width":"600px","height":"350px","centre":false,"title":"","label":"","icon":"","visitedicon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"wmsoverlay":"","layers":[],"controls":["pan","zoom","type","scale","streetview"],"zoomstyle":"DEFAULT","typestyle":"DEFAULT","autoinfowindows":false,"kml":[],"gkml":[],"fusiontables":[],"resizable":false,"tilt":0,"kmlrezoom":false,"poi":true,"imageoverlays":[],"markercluster":false,"searchmarkers":"","locations":[{"text":"","title":"","link":null,"lat":38.9498727,"lon":-105.0031457,"alt":0,"address":"","icon":"","group":"","inlineLabel":"","visitedicon":""}]}

176

Delay time calculation for dual-wavelength quantum cascade lasers  

SciTech Connect (OSTI)

In this paper, we calculate the turn-on delay (t{sub th}) and buildup (?t) times of a midinfrared quantum cascade laser operating simultaneously on two laser lines having a common upper level. The approach is based on the four-level rate equations model describing the variation of the electron number in the states and the photon number present within the cavity. We obtain simple analytical formulae for the turn-on delay and buildup times that determine the delay times and numerically apply our results to both the single and bimode states of a quantum cascade laser, in addition the effects of current injection on t{sub th} and ?t are explored.

Hamadou, A., E-mail: abd-hamado@yahoo.fr [Dpartement des Sciences et Techniques, Facult des Sciences et de la Technologie, Universit de Bordj Bou Arreridj 34000 (Algeria); Laboratoire dtude des surfaces et interfaces des matriaux solides (LESIMS), Stif 19000 (Algeria); Lamari, S. [Laboratoire dtude des surfaces et interfaces des matriaux solides (LESIMS), Stif 19000 (Algeria); Dpartement de Physique, Facult des Sciences, Universit Stif 1, 19000 (Algeria); Thobel, J.-L. [Institut d'Electronique, de Microlectronique et de Nanotechnologie (IEMN), UMR 8520, Universit Lille1, Avenue Poincar, BP 60069, 59652 Villeneuve d'Ascq Cdex (France)

2013-11-28T23:59:59.000Z

177

The critical tension in the 6D Cascading DGP model  

E-Print Network [OSTI]

We investigate the presence of ghosts in the Cascading DGP model. We start by discussing the problem of the cosmological late time acceleration, and we introduce the modified gravity approach. We then focus on brane induced gravity models and in particular on the Cascading DGP model. We consider a specific realization of the latter model, and we study first order perturbations around pure tension solutions. In the scalar sector of a 4D scalar-vector-tensor decomposition, the dynamics on the 4D brane can be described by a master equation where a critical tension emerges in a suitable 4D limit. We give a geometrical interpretation of this critical tension, and explain its relevance for the presence of ghosts in the theory. We comment on the difference between our result and the one present in the literature, and stress its importance regarding the phenomenological viability of the model. We finally provide a numerical check which confirms the validity of our analysis.

Sbisa', Fulvio

2014-01-01T23:59:59.000Z

178

Cascade Apartments - Deep Energy Multifamily Retrofit , Kent, Washington (Fact Sheet)  

SciTech Connect (OSTI)

In December of 2009-10, King County Housing Authority (KCHA) implemented energy retrofit improvements in the Cascade multifamily community, located in Kent, Washington (marine climate.)This research effort involved significant coordination from stakeholders KCHA, WA State Department of Commerce, utility Puget Sound Energy, and Cascade tenants. This report focuses on the following three primary BA research questions : 1. What are the modeled energy savings using DOE low income weatherization approved TREAT software? 2. How did the modeled energy savings compare with measured energy savings from aggregate utility billing analysis? 3. What is the Savings to Investment Ratio (SIR) of the retrofit package after considering utility window incentives and KCHA capitol improvement funding.

Not Available

2014-02-01T23:59:59.000Z

179

Enhanced Kerr electro-optic nonlinearity through cascaded Pockels effects  

E-Print Network [OSTI]

We demonstrated a large enhancement of Kerr electro-optic nonlinearity through cascaded Pockels effects in a domain inversion ferroelectric crystal. We designed a structure that can implement the cascaded Pockels effects and second-harmonic generation simultaneously. The energy coupling between the fundamental lights of different polarizations led to a large nonlinear phase shift, and thus an effective electro-optic nonlinear refractive index. The effective nonlinearity can be either positive or negative, causing the second-harmonic spectra to move towards the coupling center, which in turn, offered us a way to measure the effective electro-optic nonlinear refractive index. The corresponding enhanced Kerr electro-optic nonlinearity is more than three orders of magnitude higher than the intrinsic value. These results open a door to manipulate the nonlinear phase by applying external electric field instead of light intensity in noncentrosymmetric crystals.

Li, Guang-Zhen; Jiang, Hao-Wei; Chen, Xian-Feng

2015-01-01T23:59:59.000Z

180

Finite-time cascaded tracking control approach for mobile robots  

Science Journals Connector (OSTI)

Abstract This paper develops a new control approach for trajectory tracking of mobile robots. For the purpose of tracking trajectory, the error dynamics of a mobile robot are divided into a first-order subsystem and a second-order subsystem by using a cascaded control design. Firstly, a global finite-time control law of the angular velocity is designed for the first-order system in order to stabilize the angle error of mobile robots. Subsequently, a finite-time sliding mode control law of forward velocity is synthesized, which guarantees the global stability of the second-order subsystem. Furthermore, the global uniform stability of the whole closed-loop system is analyzed by employing cascaded control theory, and some sufficient conditions are derived. Finally, the proposed control algorithm is applied to mobile robots, where simulation results demonstrate good convergence and performance.

Yangming Zhang; Guorong Liu; Biao Luo

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "region cascades gea" 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

Microsoft Word - Cascade Networks Allston Substation LURR CX.doc  

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

15, 2011 15, 2011 REPLY TO ATTN OF: KEC-4 SUBJECT: Environmental Clearence Memorandum Harold Grappe - TELP-TPP-3 Proposed Action: Cascade Networks, Inc. LURR at Allston Substation Budget Information: Work Order # 00275035 Task 03 Categorical Exclusions Applied (from Subpart D, 10 C.F.R. Part 1021: B1.7 "Acquisition, installation, operation, and removal of communication systems, data processing equipment, and similar electronic equipment." B4.7 "Adding fiber optic cable to transmission structures..." Location: Section 10, Township 7 North, Range 3 West of the Delena Quadrangle located in Columbia County, Oregon Proposed by: Bonneville Power Administration (BPA) Description of the Proposed Action: BPA proposes to grant Cascade Networks, Inc. permission to

182

GaInAs/AlInAs quantum cascade laser design based on optimized second harmonic generation  

Science Journals Connector (OSTI)

In this work, we present an innovative procedure for the design and optimization of GaInAs/AlInAs quantum cascade laser (QCL) structures based on the use of the genetic algorithm. The purpose of the algorithm is to determine the set of design parameters that would enable the maximization of the second order nonlinear susceptibility, thus facilitating significant optical nonlinearities to take place. In our optimization model, we start from the existing design in which the active region consists of two coupled InGaAs quantum wells separated by an AlInAs barrier, and the active region levels form double resonant nonlinear cascades. Upon obtaining the optimized structure and evaluating its energies and wave functions, the output characteristics are calculated by applying the full self-consistent rate equation modeling of the electron transport in a periodic QCL structure. The results of the calculations predict a noticeable improvement of targeted properties of the optimized design, while at the same time the original design calculations show excellent agreement with experimental results. The described procedure is applicable to various active region designs and can be used for other wavelength ranges.

A Gaji?; J Radovanovi?; V Milanovi?; D Indjin; Z Ikoni?

2014-01-01T23:59:59.000Z

183

Gain spectra and temperature characteristics of quantum cascade lasers  

Science Journals Connector (OSTI)

We have developed a theory describing the operation of lasers based on intersubband transitions in a quantum well. The theory combines a first-principles description of the intersubband lineshape and the optical gain with kinetic models for carrier heating. ... Keywords: carrier heating, gain spectra, intersubband lineshape, intersubband transitions, kinetic models, laser theory, optical gain, quantum cascade lasers, quantum well, quantum well lasers, room-temperature high-power operation, temperature characteristics

V. Gorfinkel; S. Luryi; B. Gelmont

1995-11-01T23:59:59.000Z

184

Deeply etched waveguide structures for quantum cascade lasers  

Science Journals Connector (OSTI)

A high density plasma process was developed for reactive ion etching (RIE) of GaAs/AlGaAs based devices which can be applied for the processing of advanced resonator designs. We present diffractive resonators fabricated using inductively coupled plasma ... Keywords: 42.55.Px, 42.55.Xi, 78.67.De, 81.65.Cf, Deep etching, Distributed feedback, Photonic crystals, Quantum cascade lasers

S. Schartner; S. Golka; C. Pflgl; W. Schrenk; G. Strasser

2006-04-01T23:59:59.000Z

185

Unexpected Copper-Catalyzed Cascade Synthesis of Quinazoline Derivatives  

Science Journals Connector (OSTI)

Unexpected Copper-Catalyzed Cascade Synthesis of Quinazoline Derivatives ... Nitrogen-containing heterocycles are present in a wide variety of bioactive natural products and biological molecules that may be good drug candidates. ... To our surprise, the trace of unexpected 2-phenylquinazoline (3a) was observed by gas chromatography/mass spectrometry (electron ionization) [GC/MS (EI)] analysis during the process of performing the above condensation reaction in the presence of ceric ammonium nitrate (CAN). ...

Zhongyan Chen; Jiuxi Chen; Miaochang Liu; Jinchang Ding; Wenxia Gao; Xiaobo Huang; Huayue Wu

2013-10-17T23:59:59.000Z

186

A Thermal Cascade Route to Pyrroloisoindolone and Pyrroloimidazolones  

Science Journals Connector (OSTI)

A Thermal Cascade Route to Pyrroloisoindolone and Pyrroloimidazolones ... However, we have shown that pyrrolizin-3-ones 1 and related ring systems can be conveniently made in the gas phase by flash vacuum pyrolysis (FVP) of Meldrum's acid derivatives6,7 (the Meldrum's route) and by FVP of pyrrol-2-ylacrylate derivatives (the C-acrylate route). ... This always overrides the natural direction of migration in the unsubstituted ring system. ...

Hamish McNab; Richard G. Tyas

2007-10-19T23:59:59.000Z

187

THz quantum cascade lasers for standoff molecule detection.  

SciTech Connect (OSTI)

Remote optical detection of molecules, agents, and energetic materials has many applications to national security interests. Currently there is significant interest in determining under what circumstances THz frequency coverage will aid in a complete sensing package. Sources of coherent THz frequency (i.e. 0.1 to 10 THz) electromagnetic radiation with requisite power levels, frequency agility, compactness and reliability represent the single greatest obstacle in establishing a THz technology base, but recent advances in semiconductor-based quantum cascade lasers (QCLs) offer huge improvements towards the ultimate THz source goals. This project advanced the development of narrow-linewidth THz quantum cascade lasers. We developed theoretical tools to guide the improvement of standard THz quantum cascade lasers, the investigation of nonlinear optics employing infrared QCLs, and the exploration of quantum coherence to improve QCL performance. The latter was aimed especially towards achieving high temperature operation. In addition we developed a computer algorithm capable of shifting the frequencies of an existing THz QCL to a different frequency and invented a new type of laser that may enable room temperature THz generation in a electrically driven solid-state source.

Chow, Weng Wah; Wanke, Michael Clement; Lerttamrab, Maytee; Waldmueller, Ines

2007-10-01T23:59:59.000Z

188

Operation of terahertz quantum-cascade lasers at 164 K in pulsed mode and at 117 K in continuous-wave mode.  

SciTech Connect (OSTI)

We report the demonstration of a terahertz quantum-cascade laser that operates up to 164 K in pulsed mode and 117 K in continuous-wave mode at approximately 3.0 THz. The active region was based on a resonant-phonon depopulation scheme and a metal-metal waveguide was used for modal confinement. Copper to copper thermocompression wafer bonding was used to fabricate the waveguide, which displayed improved thermal properties compared to a previous indium-gold bonding method.

Kumar, Sushil (Massachusetts Institute of Technology, Cambridge, MA); Williams, Benjamin S. (Massachusetts Institute of Technology, Cambridge, MA); Hu, Qing (Massachusetts Institute of Technology, Cambridge, MA); Reno, John Louis

2005-04-01T23:59:59.000Z

189

Comparative performance evaluation of cascaded air-source hydronic heat pumps  

Science Journals Connector (OSTI)

Abstract The results are reported of an investigation of the effects of cascading air-source heat pumps on performance for hydronic residential systems. Three heat pump systems are modeled as single-stage, single-refrigerant cascaded, and two-refrigerant cascaded. Energy and exergy analyses are performed, and a comparative performance analysis is carried out, considering energy efficiency, refrigerant mass flow rates, evaporator pressure, exergy efficiency, and several other criteria. Three sets of source and supply temperatures, representing different climates and different water sink systems (low, medium and high temperature), are used to provide more comprehensive behavior assessments of the systems. Additionally, the optimum intermediate pressure of the cascaded systems for all working temperature pairs is found for the highest energetic COP and exergetic COP. Compared to a single stage heat pump, cascading improves the overall energy efficiency of the system for low-ambient temperatures, but not for high-ambient temperatures. Although this improvement is minor, the exergetic COP is increased by 67% for the single refrigerant cascaded system and 70% for a two-refrigerant cascaded system, at low ambient temperatures. Using refrigerant R404A in the low-pressure cycle marginally improves the energetic COP of the cascaded heat pump, but increases the evaporator working pressure, making it possible to use smaller compressors. However, the overall refrigerant mass flow rates increase with cascading. The two cascaded systems have higher exergy destructions (by almost four times) compared to the single stage system, mainly due to having more components, including an intermediate heat exchanger. Also, cascading shifts the major exergy destruction centers from the compressors and expansion valves to the evaporators. A comparison of cascaded and single-stage heat pumps shows that the exergy analysis results exhibit a different trend than energy analysis results with source and supply temperatures, highlighting the advantages of exergy methods in determining if cascading is appropriate for a given application.

R. Soltani; I. Dincer; M.A. Rosen

2015-01-01T23:59:59.000Z

190

Ahuachapan Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

Activities (0) 10 References Area Overview Geothermal Area Profile Location: El Salvador Exploration Region: Central American Volcanic Arc Chain GEA Development Phase: Phase...

191

Berln Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

Activities (0) 10 References Area Overview Geothermal Area Profile Location: El Salvador Exploration Region: Central American Volcanic Arc Chain GEA Development Phase: Phase...

192

Las Tres Virgenes Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

(0) 10 References Area Overview Geothermal Area Profile Location: Baja California Sur, Mexico Exploration Region: Baja Peninsula GEA Development Phase: Coordinates:...

193

Los Humeros Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

(0) 10 References Area Overview Geothermal Area Profile Location: Chignautla, Puebla, Mexico Exploration Region: Transmexican Volcanic Belt GEA Development Phase: Phase IV -...

194

Fukushima Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

Activities (0) 10 References Area Overview Geothermal Area Profile Location: Fukushima, Japan Exploration Region: Northeast Honshu Arc GEA Development Phase: Coordinates:...

195

Job 4459300 Ref.No. Prepd. CHP/GEA  

E-Print Network [OSTI]

Auditing of Buildings and Inspection of Boilers and Air- conditioning Systems Final report Institutional in large buildings 5 2.2 Article 8, Inspection of boilers 6 2.3 Article 9, Inspection of air-conditioning, responsibility for buildings, boilers and air-con systems in Latvia is divided as illustrated below

196

CanGEA Fifth Annual Geothermal Conference Presentation - Mapping...  

Energy Savers [EERE]

& Database Workshop Mapping and database workshop presentation presented at the Canadian Geothermal Energy Association Fifth Annual Geothermal Conference on March 21, 2013 by...

197

Property:Plants with Unknown Planned Capacity | Open Energy Information  

Open Energy Info (EERE)

Plants with Unknown Planned Capacity Plants with Unknown Planned Capacity Jump to: navigation, search Property Name Plants with Unknown Planned Capacity Property Type String Description Number of plants with unknown planned capacity per GEA Pages using the property "Plants with Unknown Planned Capacity" Showing 21 pages using this property. A Alaska Geothermal Region + 1 + C Cascades Geothermal Region + 2 + Central Nevada Seismic Zone Geothermal Region + 9 + G Gulf of California Rift Zone Geothermal Region + 4 + H Hawaii Geothermal Region + 0 + Holocene Magmatic Geothermal Region + 0 + I Idaho Batholith Geothermal Region + 1 + N Northern Basin and Range Geothermal Region + 11 + Northern Rockies Geothermal Region + 0 + Northwest Basin and Range Geothermal Region + 9 + R Rio Grande Rift Geothermal Region + 1 +

198

Modernization of the guide bearings of turbines of the cascade of Chirchik hydroelectric stations  

Science Journals Connector (OSTI)

The favorable experience of reconstruction and subsequent operation of the guide bearings of turbines of the cascade of Chirchik hydrostations confirms the possibility of modernizing bearings under conditions ...

V. V. Balagurov; Yu. P. Maizel'; M. A. Tsvetkova

1981-08-01T23:59:59.000Z

199

Faraday rotation spectroscopy of nitrogen dioxide based on a widely tunable external cavity quantum cascade laser  

E-Print Network [OSTI]

Faraday rotation spectroscopy of nitrogen dioxide based on a widely tunable external cavity quantum: Faraday Rotation Spectroscopy, external-cavity quantum cascade laser, nitrogen dioxide, trace

200

External Cavity Quantum Cascade Lasers: Recent Advances, Applications, and Comparisons with Alternative Sources in the MIR  

Science Journals Connector (OSTI)

The performance of external cavity quantum/interband cascade lasers (ECqcL/ECicL) in molecular detection and imaging applications will be discussed. Alternative MIR laser technologies...

Day, Timothy

Note: This page contains sample records for the topic "region cascades gea" 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.


201

Limiting Factors for High Temperature Operation of THz Quantum Cascade Lasers  

Science Journals Connector (OSTI)

We theoretically investigate the temperature dependence of the carrier transport in GaAs-based THz quantum cascade lasers and identify the factors restricting high-temperature...

Jirauschek, Christian; Lugli, Paolo

202

Quantum cascade laser spectrometer for trace-gas detection of exhaled Carbonyl Sulfide  

Science Journals Connector (OSTI)

Simultaneous concentration measurements of exhaled carbonyl sulfide and carbon dioxide were demonstrated using a pulsed quantum cascade laser based gas sensor. This sensor has...

Wysocki, Gerard; So, Stephen; McCurdy, Matt; Roller, Chad; Weidmann, Damien; Kosterev, Anatoliy a; Frantz, J Patrick; Curl, Robert F; Tittel, Frank K

203

THz Quantum Cascade Lasers Grown by Low-Pressure Metalorganic Vapor Phase Epitaxy  

Science Journals Connector (OSTI)

A terahertz quantum cascade laser (QCL) has been successfully grown by low-pressure MOVPE. Very high quality semiconductor interfaces are demonstrated as well as very promising lasing...

Sirigu, Lorenzo; Rudra, Alok; Amanti, Maria I; Scalari, Giacomo; Fischer, Milan; Giovannini, Marcella; Faist, Jerome; Kapon, Eli

204

E-Print Network 3.0 - acid cascade enzymes Sample Search Results  

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

Biology and Medicine 38 Computational Modelling of Kinase Signalling Cascades David Gilbert, Monika Heiner, Rainer Breitling, and Richard Orton Summary: of Kinase Signalling...

205

Atomistic Modeling of Displacement Cascades in La2Zr2O7 Pyrochlore...  

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

point defects, such as cations antisites configurations, various interstitials, and vacancies. There is no evidence for direct amorphization within the cascades. The results are...

206

Cascaded Cerenkov third-harmonic generation in random quadratic media  

SciTech Connect (OSTI)

We investigate experimentally and theoretically the conical emission of Cerenkov-type third-harmonic generation in strontium barium niobate of random 2D-{chi}{sup (2)} distribution. The azimuthal intensity distribution is explained by the polarization properties of the fundamental and Cerenkov second-harmonic waves, depending on the cascaded origin of the generation process. Moreover, we show the role of the individual domain shape in an additional modulation on the conical emission, controlled by the electrical switching of the spontaneous polarization of the ferroelectric medium.

Ayoub, Mousa; Roedig, Philip; Imbrock, Joerg; Denz, Cornelia [Institute of Applied Physics and Center for Nonlinear Science (CeNoS), Westfaelische Wilhelms-Universitaet Muenster, Corrensstrasse 2, 48149 Muenster (Germany)

2011-12-12T23:59:59.000Z

207

Entanglement amplification in a nondegenerate three-level cascade laser  

SciTech Connect (OSTI)

We analyze a nondegenerate three-level cascade laser coupled to a two-mode vacuum reservoir employing the stochastic differential equations associated with the normal ordering. We study the squeezing properties and entanglement amplification of the cavity radiation. We also calculate the correlation of the photon numbers and the fluctuations of the intensity difference. It turns out that the generated light exhibits a two-mode squeezing and entanglement when initially there are more atoms in the lower level. Moreover, a strong correlation between photon numbers along with a significant fluctuation in the intensity difference is found.

Tesfa, Sintayehu [Physics Department, Addis Ababa University, P. O. Box 1176, Addis Ababa (Ethiopia)

2006-10-15T23:59:59.000Z

208

Synthesis of a Leucomitosane via a Diastereoselective Radical Cascade  

Science Journals Connector (OSTI)

GC analyses were carried out on a GC instrument fitted with an Optima delta-3-0.25 ?m capillary column (20 m, 0.25 mm); gas carrier, He 1.4 mL/min; injector, 220 C split mode; detector, FID 280 C, H2 35 mL/min, air 350 mL/min. ... cascade of a 1,3,4-oxadiazole in which the pentacyclic skeleton and all the stereochem. of the natural products are assembled in a reaction that forms three rings, four C-C bonds, and five stereogenic centers including three contiguous quaternary centers, and introduces the correct oxidn. ...

Franois Brucelle; Philippe Renaud

2013-05-30T23:59:59.000Z

209

CP-violation in SUSY cascades at the LHC  

E-Print Network [OSTI]

We study the potential to observe CP-violating effects in SUSY cascade decay chains at the LHC. Asymmetries composed by triple products of momenta of the final state particles are sensitive to CP-violating effects. Due to large boosts that dilute the asymmetries, these can be difficult to observe. Extending the methods of momentum reconstruction we show that the original size of these asymmetries may be measurable. A study is done at the hadronic level with backgrounds to estimate the expected sensitivity at the LHC.

Jamie Tattersall; Gudrid Moortgat-Pick; Krzysztof Rolbiecki

2010-09-01T23:59:59.000Z

210

Property:Number of Plants Included in Planned Estimate | Open Energy  

Open Energy Info (EERE)

Plants Included in Planned Estimate Plants Included in Planned Estimate Jump to: navigation, search Property Name Number of Plants Included in Planned Estimate Property Type String Description Number of plants included in the estimate of planned capacity per GEA Pages using the property "Number of Plants Included in Planned Estimate" Showing 21 pages using this property. A Alaska Geothermal Region + 3 + C Cascades Geothermal Region + 1 + Central Nevada Seismic Zone Geothermal Region + 4 + G Gulf of California Rift Zone Geothermal Region + 7 + H Hawaii Geothermal Region + 1 + Holocene Magmatic Geothermal Region + 4 + I Idaho Batholith Geothermal Region + 1 + N Northern Basin and Range Geothermal Region + 9 + Northern Rockies Geothermal Region + 0 + Northwest Basin and Range Geothermal Region + 6 +

211

Additional bands of the ArD2O intramolecular bending mode observed using a quantum cascade laser  

Science Journals Connector (OSTI)

Three new rovibrational bands of ArD2O have been observed in the ?2 bending region of D2O using a quantum cascade laser based cavity ringdown spectrometer. In addition, further observations of the ?(110, ?2=1)??(101) band reported by Li et al. (J. Mol. Spectrosc. 272 (2012) 2731) have been made. All bands were fit by treating the complex using a pseudo-diatomic model which treats the D2O as a free rotor within the complex. Molecular constants have been obtained using this model and are reported with deviations in the fits ranging from 0.0002cm?1 to 0.0005 cm?1. Two of the newly observed bands are tentatively assigned as the ?(202, ?2=1)??(111) and ?(211, ?2=1)??(202) bands, which have not previously been observed in other spectral regions.

Jacob T. Stewart; Benjamin J. McCall

2012-01-01T23:59:59.000Z

212

Criticality safety concerns of uranium deposits in cascade equipment  

SciTech Connect (OSTI)

The Paducah and Portsmouth Gaseous Diffusion Plants enrich uranium in the {sup 235}U isotope by diffusing gaseous uranium hexafluoride (UF{sub 6}) through a porous barrier. The UF{sub 6} gaseous diffusion cascade utilized several thousand {open_quotes}stages{close_quotes} of barrier to produce highly enriched uranium (HEU). Historically, Portsmouth has enriched the Paducah Gaseous Diffusion Plant`s product (typically 1.8 wt% {sup 235}U) as well as natural enrichment feed stock up to 97 wt%. Due to the chemical reactivity of UF{sub 6}, particularly with water, the formation of solid uranium deposits occur at a gaseous diffusion plant. Much of the equipment operates below atmospheric pressure, and deposits are formed when atmospheric air enters the cascade. Deposits may also be formed from UF{sub 6} reactions with oil, UF{sub 6} reactions with the metallic surfaces of equipment, and desublimation of UF{sub 6}. The major deposits form as a result of moist air in leakage due to failure of compressor casing flanges, blow-off plates, seals, expansion joint convolutions, and instrument lines. This report describes criticality concerns and deposit disposition.

Plaster, M.J. [Lockheed Martin Utility Services, Inc., Piketon, OH (United States)

1996-12-31T23:59:59.000Z

213

Modified gravity, the Cascading DGP model and its critical tension  

E-Print Network [OSTI]

We investigate the presence of instabilities in the Cascading DGP model. We start by discussing the problem of the cosmological late time acceleration, and we introduce the modified gravity approach. We then focus on brane induced gravity models and in particular on the Cascading DGP model. We consider configurations of the latter model where the source term is given simply by vacuum energy (pure tension), and we study perturbations at first order around these configurations. We perform a four-dimensional scalar-vector-tensor decomposition of the perturbations, and show that, regarding the scalar sector, the dynamics in a suitable limit can be described by a master equation. This master equation contains an energy scale (critical tension) which is related in a non-trivial way to the parameters of the model. We give a geometrical interpretation of why this scale emerges, and explain its relevance for the presence of ghost instabilities in the theory. We comment on the difference between our result and the one present in the literature, and stress its importance regarding the phenomenological viability of the model. We finally provide a numerical check which confirms the validity of our analysis.

Fulvio Sbisa'

2014-12-17T23:59:59.000Z

214

Superfluid Turbulence from Quantum Kelvin Wave to Classical Kolmogorov Cascades  

SciTech Connect (OSTI)

The main topological feature of a superfluid is a quantum vortex with an identifiable inner and outer radius. A novel unitary quantum lattice gas algorithm is used to simulate quantum turbulence of a Bose-Einstein condensate superfluid described by the Gross-Pitaevskii equation on grids up to 5760{sup 3}. For the first time, an accurate power-law scaling for the quantum Kelvin wave cascade is determined: k{sup -3}. The incompressible kinetic energy spectrum exhibits very distinct power-law spectra in 3 ranges of k space: a classical Kolmogorov k{sup -(5/3)} spectrum at scales greater than the outer radius of individual quantum vortex cores and a quantum Kelvin wave cascade spectrum k{sup -3} on scales smaller than the inner radius of the quantum vortex core. The k{sup -3} quantum Kelvin wave spectrum due to phonon radiation is robust, while the k{sup -(5/3)} classical Kolmogorov spectrum becomes robust on large grids.

Yepez, Jeffrey [Air Force Research Laboratory, Hanscom Air Force Base, Massachusetts 01731 (United States); Vahala, George [Department of Physics, William and Mary, Williamsburg, Virginia 23185 (United States); Vahala, Linda [Department of Electrical and Computer Engineering, Old Dominion University, Norfolk, Virginia 23529 (United States); Soe, Min [Department of Mathematics and Physical Sciences, Rogers State University, Claremore, Oklahoma 74017 (United States)

2009-08-21T23:59:59.000Z

215

Direct and Inverse Cascades in the Wind-Driven Sea  

E-Print Network [OSTI]

We offer a new form for the S(nl) term in the Hasselmann kinetic equation for squared wave amplitudes of wind-driven gravity wave. This form of S(nl) makes possible to rewrite in differential form the conservation laws for energy, momentum, and wave action, and introduce their fluxes by a natural way. We show that the stationary kinetic equation has a family of exact Kolmogorov-type solutions governed by the fluxes of motion constants: wave action, energy, and momentum. The simple "local" model for S(nl) term that is equivalent to the "diffusion approximation" is studied in details. In this case, Kolmogorov spectra are found in the explicit form. We show that a general solution of the stationary kinetic equation behind the spectral peak is described by the Kolmogorov-type solution with frequency-dependent fluxes. The domains of "inverse cascade" and "direct cascade" can be separated by natural way. The spectrum in the universal domain is close to $\\omega^{-4}$.

Zakharov, Vladimir E

2015-01-01T23:59:59.000Z

216

Risk-aware Attacks and Catastrophic Cascading Failures in U.S. Power Grid  

E-Print Network [OSTI]

Risk-aware Attacks and Catastrophic Cascading Failures in U.S. Power Grid Wenkai Wang, Qiao Cai Department, Stevens Institute of Technology, Hoboken, NJ 07030 Abstract--The power grid network is a complex of power grid in terms of cascading failures caused by node failures. Specifically, we define three metrics

Sun, Yan Lindsay

217

A Five-Level Three-Phase Hybrid Cascade Multilevel Inverter Using a Single DC Source  

E-Print Network [OSTI]

A Five-Level Three-Phase Hybrid Cascade Multilevel Inverter Using a Single DC Source for a PM to construct a 3-phase 5-level cascade multilevel inverter to be used as a drive for a PM traction motor. The 5-level inverter consists of a standard 3-leg inverter (one leg for each phase) and an H-bridge in series

Tolbert, Leon M.

218

Hybrid Cascaded H-bridges Multilevel Motor Drive Control for Electric Vehicles  

E-Print Network [OSTI]

Hybrid Cascaded H-bridges Multilevel Motor Drive Control for Electric Vehicles Zhong Du1 , Leon M vehicle motor drive applications and hybrid electric vehicle motor drive applications. Keywords: hybrid cascaded H-bridge multilevel converter, DC voltage balance control, multilevel motor drive, electric

Tolbert, Leon M.

219

Mode tuning of quantum cascade lasers through optical processing of chalcogenide glass claddings  

E-Print Network [OSTI]

. The nature of gas-sensing applications requires single- mode operation and good tunability. One wayMode tuning of quantum cascade lasers through optical processing of chalcogenide glass claddings July 2006 In this letter, we demonstrate a method of tuning quantum cascade QC lasers by modifying

Arnold, Craig B.

220

A quantum cascade laser fabricated using planar native-oxide layers C. D. Farmera)  

E-Print Network [OSTI]

of quantum cascade lasers. The native oxide of the Al0.48In0.52As upper cladding layer was formed and usedA quantum cascade laser fabricated using planar native-oxide layers C. D. Farmera) Department to provide electrical and optical confinement for lasers operating at 5 m. Initial results include 1.4 W peak

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221

Design of Microsecond Level and High Current Pulse Driver Systems for Quantum Cascade Lasers  

Science Journals Connector (OSTI)

This paper presents a microsecond, high current pulse generator to drive quantum cascade lasesrs. The driver systems consist of pulse generator; power amplifier; fast switches and constant current supply circuits. The pulse width and pulse repetition ... Keywords: microsecond level, high current, pulesd driver systems, quantum cascade laser

Lei Li; Chen Chen; Hai Yu; Chengjun Dong; Yiding Wang

2010-06-01T23:59:59.000Z

222

Ugi post-condensation copper-triggered oxidative cascade towards pyrazoles  

E-Print Network [OSTI]

1310 Ugi post-condensation copper-triggered oxidative cascade towards pyrazoles Aurélie Dos Santos-component Ugi coupling, the resulting hydrazone was engaged in a copper triggered [3 + 2] cycloaddition/aerobic oxidation cascade. 1310 Introduction In the last twenty years, the Ugi reaction coupled with its various

Paris-Sud XI, Université de

223

Universal Laws of Cascade of Turbulent Fluctuations ZhenSu She  

E-Print Network [OSTI]

1 Universal Laws of Cascade of Turbulent Fluctuations Zhen­Su She Department of Mathematics interactions. As fluctuations cascade, both mechanical law and statistical law are important to determine that the fundamental mechanical conception of the nature was doubteful when such phenomena as the heat radiation

Soatto, Stefano

224

Transient dynamics and foodweb complexity in the LotkaVolterra cascade model  

Science Journals Connector (OSTI)

...research-article Transient dynamics and food-web complexity in the Lotka-Volterra cascade...behaviour near equilibrium of model food webs correlate with their short-term transient...Lotka-Volterra cascade model of food webs provide the first evidence to answer this...

2001-01-01T23:59:59.000Z

225

Cascadability and reshaping properties of a saturable absorber inserted inside a RZ transmission line for future  

E-Print Network [OSTI]

absorber component cascaded into a 100-km SMF RZ transmission line in order to annihilate the ghost paid to transmission lines working at higher bit-rates, such as 160 Gbit/s [1]. However, many studies Absorber device cascaded inside a 100-km Single Mode Fiber (SMF)- based RZ transmission line cadenced

Paris-Sud XI, Université de

226

Number and propagation of line outages in cascading events in electric power transmission systems  

E-Print Network [OSTI]

Number and propagation of line outages in cascading events in electric power transmission systems of transmission lines. We estimate from observed utility data how transmission line outages propagate, and obtain of transmission lines. The multiple mechanisms involved these cascading outages are many and varied, and the power

Dobson, Ian

227

Regional Purchasing  

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

Regional Purchasing Regional Purchasing Regional Purchasing Pursuant to Appendix M of Prime Contract No. DE-AC52-06NA25396 between DOE/NNSA and Los Alamos National Security, LLC (LANS), LANS is committed to building a strong supplier base with Northern New Mexico businesses and the local Native American pueblos in the purchases of goods and services. Contact Small Business Office (505) 667-4419 Email We seek out and utilize known Northern New Mexico business as suppliers The Northern New Mexico counties included are Los Alamos Santa Fe Rio Arriba Taos Mora San Miguel Sandoval The eight regional pueblos included are Nambe Ohkay Owingeh (formerly known as San Juan) Picuris Pojoaque San Ildefonso Santa Clara Taos Tesuque When the Laboratory cannot identify regional firms, it will expand its

228

Stabilization, Injection and Control of Quantum Cascade Lasers, and Their Appli-cation to Chemical Sensing in the Infrared  

SciTech Connect (OSTI)

Quantum cascade lasers (QCLs) are a relatively new type of semiconductor laser operating in the mid- to long-wave infrared. These monopolar multilayered quantum well structures can be fabricated to operate anywhere between 3.5 microns and 20 microns, which includes the molecular fingerprint region of the in-frared. This makes them an ideal choice for infrared chemical sensing, a topic of great interest at present. Frequency stabilization and injection locking increase the utility of QCLs. We present results of locking quantum cascade lasers to optical cavities, achieving relative linewidths down to 5.6 Hz. We report injec-tion locking of one distributed feedback grating QCL with light from a similar QCL, demonstrating capture ranges of up to 500 MHz, and suppression of amplitude modulation by up to 49 dB. We also present various cavity-enhanced chemical sensors employing the frequency stabilization techniques developed, in-cluding the resonant sideband technique known as Nice-Ohms. Sensitivities of 9.7 x 10-11 cm-1 Hz-1/2 have been achieved in nitrous oxide.

Taubman, Matthew S.; Myers, Tanya L.; Cannon, Bret D.; Williams, Richard M.

2004-12-01T23:59:59.000Z

229

Inductorless DC-AC Cascaded H-bridge Multilevel Boost Inverter for Electric/Hybrid Electric Vehicle  

E-Print Network [OSTI]

Inductorless DC-AC Cascaded H-bridge Multilevel Boost Inverter for Electric/Hybrid Electric Vehicle University Boise, ID 83725, USA Abstract-This paper presents an inductorless cascaded H- bridge multilevel a bulky inductor. An inductorless cascaded H-bridge multilevel boost inverter for EV and HEV applications

Tolbert, Leon M.

230

Cascade Natural Gas - Conservation Incentives for Existing Homes |  

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

Existing Homes Existing Homes Cascade Natural Gas - Conservation Incentives for Existing Homes < Back Eligibility Residential Savings Category Home Weatherization Commercial Weatherization Sealing Your Home Ventilation Heating & Cooling Commercial Heating & Cooling Heating Appliances & Electronics Water Heating Program Info State District of Columbia Program Type Utility Rebate Program Rebate Amount Floor Insulation: $0.45 per sq. ft. Wall Insulation: $0.40 per sq. ft. Ceiling or Attic Insulation: $0.25 per sq. ft. High Efficiency Natural Gas Furnace: $150 Duct Sealing: $150 High Efficiency Natural Gas Furnace and Duct Sealing: $400 High Efficiency Natural Gas Hearth: $70 Conventional Natural Gas Water Heater: $40 Combination Domestic Water/Hydronic Space Heating System (using Tankless

231

Collision cascades and sputtering induced by larger cluster ions  

SciTech Connect (OSTI)

Recent experimental work on larger cluster impact on solid surfaces suggests large deviations from the standard case of additive sputter yields both in the nuclear and electronic stopping regime. The paper concentrates on elastic collision cascades. In addition to very pronounced spike effects, two phenomena are pointed out that are specific to cluster bombardment. Multiple hits of cluster atoms on one and the same target atom may result in recoil atoms that move faster than the maximum recoil speed for monomer bombardment at the same projectile speed. This effect is important when the atomic mass of a beam atom is less than that of a target atom, M1 << M2. In the opposite case, M1 >> M2, collisions between beam particles may accelerate some beam particles and slow down others. Some consequences are mentioned. Remarks on the nuclear stopping power of larger clusters and on electronic sputtering by cluster bombardment conclude the paper. 38 refs., 2 figs.

Sigmund, P.

1988-01-01T23:59:59.000Z

232

Advanced quantum cascade laser transmitter architectures and infrared photonics development  

SciTech Connect (OSTI)

Quantum cascade lasers (QCLs) provide a viable infrared laser source for a new class of laser transmitters capable of meeting the performance requirements for a variety of national security and civilian applications. The high output power, small size, and superb stability and modulation characteristics of QCLs make them amenable for integration as transmitters into ultra-sensitive, ultra-selective point sampling and remote short-range chemical sensors. This paper reports on the current development in infrared photonics that provides a pathway for QCL transmitter miniaturization. This research has produced infrared waveguide-based optical components in chalcogenide glass using both direct-laser writing and holographic exposure techniques. We discuss here the design and fabrication concepts and capabilities required to produce integrated waveguides, waveguide couplers, and other photonic devices.

Anheier, Norman C.; Allen, Paul J.; Myers, Tanya L.

2004-08-01T23:59:59.000Z

233

Analytical investigation of the dynamics behaviors of quantum cascade laser  

Science Journals Connector (OSTI)

Abstract In this paper, we investigate analytically and numerically the transient dynamics of the mid-infrared quantum cascade laser operating in a single mode. The approach is based on using adiabatic elimination in the rate equations model. Analytical solutions are derived for steady-state and time-dependent number of electrons in the various levels, population inversion and number of photons in the cavity. In addition, the equation that allows for the determination of time for steady-state establishment is derived within the premises of our analytical model in the most general case. The results are compared with numerical calculations. The dependence of the buildup time on current injection is also examined and compared with our other existing model.

A. Hamadou

2015-01-01T23:59:59.000Z

234

Controllable discrete diffraction in cascade-induced waveguides  

SciTech Connect (OSTI)

A new method for generating periodic lattices in quadratically nonlinear media by the three-wave cascade interaction is proposed. This method allows one to obtain stable structures with changeable parameters. These structures make it possible to realise the all-optical control of the character of the laser beam propagation. The use of the discrete diffraction allows the signal multiplexing in optical processing and information transfer devices and the control of the number of channels at the crystal output. The effect of the discrete diffraction anisotropy in the system of induced waveguides makes it possible to redistribute in the specified way the energy in the channels at the output. It is shown that the optical switching efficiency is maximal in the regime of the transverse Bragg resonance. The signal switching rate in optical lattices induced in a quadratically nonlinear medium is limited by the time of light propagation though the crystal and can achieve several terahertz. (nonlinear optical phenomena)

Borovkova, O V; Lobanov, V E; Sukhorukov, Anatolii P [M. V. Lomonosov Moscow State University, Faculty of Physics, Moscow (Russian Federation); Sukhorukova, A K [Russian State Geological Prospecting University, Moscow (Russian Federation)

2009-11-30T23:59:59.000Z

235

Multicomponent cnoidal waves in cascade parametric frequency conversion  

SciTech Connect (OSTI)

It is shown that four-mode interaction in quasi-synchronous cascade frequency conversion on a quadratic nonlinearity can be described in terms of an effective cubic nonlinearity, which reduces the problem to solving the system of two coupled nonlinear Schroedinger equations (NSEs) with respect to the amplitudes of waves involved in both nonlinear processes. Analytic solutions of a new type found for this system have the form of cnoidal waves with components representing the sum and difference of the identical fundamental solutions of the NSE with shifted arguments. The obtained solutions cover the entire range of variation of boundary conditions, allowing the optimisation of the conversion efficiency in any particular situation. (nonlinear optical phenomena)

Petnikova, V M; Shuvalov, Vladimir V [International Laser Center, M. V. Lomonosov Moscow State University, Moscow (Russian Federation)

2008-12-31T23:59:59.000Z

236

Cascaded injection resonator for coherent beam combining of laser arrays  

DOE Patents [OSTI]

The invention provides a cascaded injection resonator for coherent beam combining of laser arrays. The resonator comprises a plurality of laser emitters arranged along at least one plane and a beam sampler for reflecting at least a portion of each laser beam that impinges on the beam sampler, the portion of each laser beam from one of the laser emitters being reflected back to another one of the laser emitters to cause a beam to be generated from the other one of the laser emitters to the beam reflector. The beam sampler also transmits a portion of each laser beam to produce a laser output beam such that a plurality of laser output beams of the same frequency are produced. An injection laser beam is directed to a first laser emitter to begin a process of generating and reflecting a laser beam from one laser emitter to another laser emitter in the plurality. A method of practicing the invention is also disclosed.

Kireev, Vassili [Sunnyvale, CA; Liu, Yun; Protopopescu, Vladimir [Knoxville, TN; Braiman, Yehuda [Oak Ridge, TN

2008-10-21T23:59:59.000Z

237

City of Cascade Locks, Oregon (Utility Company) | Open Energy Information  

Open Energy Info (EERE)

Oregon (Utility Company) Oregon (Utility Company) Jump to: navigation, search Name City of Cascade Locks Place Oregon Utility Id 3136 Utility Location Yes Ownership M NERC Location WECC NERC WECC Yes Activity Distribution Yes References EIA Form EIA-861 Final Data File for 2010 - File1_a[1] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Utility Rate Schedules Grid-background.png General Service- City Commercial General Service- City(Primary Metering) Commercial General Service- Rural Commercial General Service- Rural(Primary Metering) Commercial Public Agency Rate- City Commercial Public Agency Rate- City(Primary Metering) Commercial Public Agency Rate- Rural Commercial Public Agency Rate- Rural(Primary Metering) Commercial

238

LNG cascading damage study. Volume I, fracture testing report.  

SciTech Connect (OSTI)

As part of the liquefied natural gas (LNG) Cascading Damage Study, a series of structural tests were conducted to investigate the thermal induced fracture of steel plate structures. The thermal stresses were achieved by applying liquid nitrogen (LN{sub 2}) onto sections of each steel plate. In addition to inducing large thermal stresses, the lowering of the steel temperature simultaneously reduced the fracture toughness. Liquid nitrogen was used as a surrogate for LNG due to safety concerns and since the temperature of LN{sub 2} is similar (-190 C) to LNG (-161 C). The use of LN{sub 2} ensured that the tests could achieve cryogenic temperatures in the range an actual vessel would encounter during a LNG spill. There were four phases to this test series. Phase I was the initial exploratory stage, which was used to develop the testing process. In the Phase II series of tests, larger plates were used and tested until fracture. The plate sizes ranged from 4 ft square pieces to 6 ft square sections with thicknesses from 1/4 inches to 3/4 inches. This phase investigated the cooling rates on larger plates and the effect of different notch geometries (stress concentrations used to initiate brittle fracture). Phase II was divided into two sections, Phase II-A and Phase II-B. Phase II-A used standard A36 steel, while Phase II-B used marine grade steels. In Phase III, the test structures were significantly larger, in the range of 12 ft by 12 ft by 3 ft high. These structures were designed with more complex geometries to include features similar to those on LNG vessels. The final test phase, Phase IV, investigated differences in the heat transfer (cooling rates) between LNG and LN{sub 2}. All of the tests conducted in this study are used in subsequent parts of the LNG Cascading Damage Study, specifically the computational analyses.

Petti, Jason P.; Kalan, Robert J.

2011-12-01T23:59:59.000Z

239

Regional Inventories  

Gasoline and Diesel Fuel Update (EIA)

5 5 Notes: This year has not started well for gasoline inventories, with inventories being low across regions of the country. The Midwest region (PADD II) had been running lower than most regions, but began to catch up during the last week in April. Gasoline inventories ran about 9% below their 5-year average for this time of year and about 4% below where they were last year. The recent refinery problems in the Midwest, though, could erase some of that recovery. The impacts of Tosco's Wood River refinery and Marathon's St Paul refinery are not fully realized. But inventories were also precariously low along the East Coast (PADD I) and are extremely low in the Rocky Mountain region (PADD IV), although the size of this market mitigates any national impact. While the

240

Long wave infrared cavity-enhanced sensors using quantum cascade lasers  

SciTech Connect (OSTI)

Quantum cascade lasers (QCLs) are becoming well known as convenient and stable semiconductor laser sources operating in the mid- to long-wave infrared, and are able to be fabricated to operate virtually anywhere in the 3.5 to 25 micron region. This makes them an ideal choice for infrared chemical sensing, a topic of great interest at present, spanning at least three critical areas: national security, environmental monitoring and protection, and the early diagnosis of disease through breath analysis. There are many different laser-based spectroscopic chemical sensor architectures in use today, from simple direct detection through to more complex and highly sensitive systems. Many current sensor needs can be met by combining QCLs and appropriate sensor architectures, those needs ranging from UAV-mounted surveillance systems, through to larger ultra-sensitive systems for airport security. In this paper we provide an overview of various laser-based spectroscopic sensing techniques, pointing out advantages and disadvantages of each. As part of this process, we include our own results and observations for techniques under development at PNNL. We also present the latest performance of our ultra-quiet QCL control electronics now being commercialized, and explore how using optimized supporting electronics enables increased sensor performance and decreased sensor footprint for given applications.

Taubman, Matthew S.; Scott, David C.; Myers, Tanya L.; Cannon, Bret D.

2005-12-30T23:59:59.000Z

Note: This page contains sample records for the topic "region cascades gea" 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

Measurement of Broad Absorption Features Using a Tunable External Cavity Quantum Cascade Laser  

SciTech Connect (OSTI)

We demonstrate the use of a tunable external cavity quantum cascade laser system for measurement of broad absorption features in the mid-infrared spectral region. The thermoelectrically cooled external cavity laser was tuned over a 65 cm-1 range centered at 8.7 microns using stepper motor control. Pulsing the laser at a high duty cycle provided 3-5 mW average output power over the tuning range, and enabled phase-sensitive detection of amplitude-modulated signals. We used the laser system to measure the absorption spectra of Freon-125 using a Herriott cell. In addition, the absorption spectrum of water in the laboratory air was measured. The measurements showed excellent agreement with reference spectra, in both wavelength and amplitude. The measured scan resolution of 0.14 cm-1 is suitable for measurement of the absorption features of complex molecules as well as simple molecules with atmospherically broadened lines. We discuss the limits to the scan resolution due to effects of spectral chirp and mode-hops during pulsed operation.

Phillips, Mark C.; Myers, Tanya L.; Wojcik, Michael D.; Cannon, Bret D.; Taubman, Matthew S.; Scott, David C.

2007-09-25T23:59:59.000Z

242

Astrophysical gyrokinetics: kinetic and fluid turbulent cascades in magnetized weakly collisional plasmas  

E-Print Network [OSTI]

We present a theoretical framework for plasma turbulence in astrophysical plasmas (solar wind, interstellar medium, galaxy clusters, accretion disks). The key assumptions are that the turbulence is anisotropic with respect to the mean magnetic field and frequencies are low compared to the ion cyclotron frequency. The energy injected at the outer scale scale has to be converted into heat, which ultimately cannot be done without collisions. A KINETIC CASCADE develops that brings the energy to collisional scales both in space and velocity. Its nature depends on the physics of plasma fluctuations. In each of the physically distinct scale ranges, the kinetic problem is systematically reduced to a more tractable set of equations. In the "inertial range" above the ion gyroscale, the kinetic cascade splits into a cascade of Alfvenic fluctuations, which are governed by the RMHD equations at both the collisional and collisionless scales, and a passive cascade of compressive fluctuations, which obey a linear kinetic equation along the moving field lines associated with the Alfvenic component. In the "dissipation range" between the ion and electron gyroscales, there are again two cascades: the kinetic-Alfven-wave (KAW) cascade governed by two fluid-like Electron RMHD equations and a passive phase-space cascade of ion entropy fluctuations. The latter cascade brings the energy of the inertial-range fluctuations that was damped by collisionless wave-particle interaction at the ion gyroscale to collisional scales in the phase space and leads to ion heating. The KAW energy is similarly damped at the electron gyroscale and converted into electron heat. Kolmogorov-style scaling relations are derived for these cascades. Astrophysical and space-physical applications are discussed in detail.

A. A. Schekochihin; S. C. Cowley; W. Dorland; G. W. Hammett; G. G. Howes; E. Quataert; T. Tatsuno

2007-03-31T23:59:59.000Z

243

Simulation Modeling of an Enhanced Low-Emission Swirl-Cascade Burner  

SciTech Connect (OSTI)

''Cascade-burners'' is a passive technique to control the stoichiometry of the flame through changing the flow dynamics and rates of mixing in the combustion zone with a set of venturis surrounding the flame. Cascade-burners have shown advantages over other techniques; its reliability, flexibility, safety, and cost makes it more attractive and desirable. On the other hand, the application of ''Swirl-burners'' has shown superiority in producing a stable flame under a variety of operating conditions and fuel types. The basic idea is to impart swirl to the air or fuel stream, or both. This not only helps to stabilize the flame but also enhances mixing in the combustion zone. As a result, nonpremixed (diffusion) swirl burners have been increasingly used in industrial combustion systems such as gas turbines, boilers, and furnaces, due to their advantages of safety and stability. Despite the advantages of cascade and swirl burners, both are passive control techniques, which resulted in a moderate pollutant emissions reduction compared to SCR, SNCR and FGR (active) methods. The present investigation will study the prospects of combining both techniques in what to be named as ''an enhanced swirl-cascade burner''. Natural gas jet diffusion flames in baseline, cascade, swirl, and swirl-cascade burners were numerically modeled using CFDRC package. The thermal, composition, and flow (velocity) fields were simulated. The numerical results showed that swirl and cascade burners have a more efficient fuel/air mixing, a shorter flame, and a lower NOx emission levels, compared to the baseline case. The results also revealed that the optimal configurations of the cascaded and swirling flames have not produced an improved performance when combined together in a ''swirl-cascade burner''. The non-linearity and complexity of the system accounts for such a result, and therefore, all possible combinations, i.e. swirl numbers (SN) versus venturi diameter ratios (D/d), need to be considered.

Ala Qubbaj

2004-09-01T23:59:59.000Z

244

Geology and geothermal resources of the Santiam Pass area of the Oregon Cascade Range, Deschutes, Jefferson and Linn Counties, Oregon. Final report  

SciTech Connect (OSTI)

This open-file report presents the results of the Santiam Pass drilling program. The first phase of this program was to compile all available geological, geophysical and geothermal data for the Santiam Pass area and select a drill site on the basis of these data (see Priest and others, 1987a), A summary of the drilling operations and costs associated with the project are presented in chapter 1 by Hill and Benoit. An Overview of the geology of the Santiam Pass area is presented by Hill and Priest in chapter 2. Geologic mapping and isotopic age determinations in the Santiam Pass-Mount Jefferson area completed since 1987 are summarized in chapter 2. One of the more important conclusions reached in chapter 2 is that a minimum of 2 km vertical displacement has occurred in the High Cascade graben in the Santiam Pass area. The petrology of the Santiam Pass drill core is presented by Hill in chapter 3. Most of the major volcanic units in the core have been analyzed for major, minor, and trace element abundances and have been studied petrographically. Three K-Ar ages are interpreted in conjunction with the magnetostratigraphy of the core to show that the oldest rocks in the core are approximately 1.8 Ma. Geothermal and geophysical data collected from the Santiam Pass well are presented by Blackwell in chapter 4. The Santiam Pass well failed to penetrate beneath the zone of lateral groundwater flow associated with highly permeable Quaternary volcanic rocks. Calculated geothermal gradients range from about 50{degree}C/km at depth 700-900 m, to roughly 110{degree}C/km from 900 m to the bottom of the well at 929 m. Heat-flow values for the bottom part of the hole bracket the regional average for the High Cascades. Blackwell concludes that heat flow along the High Cascades axis is equal to or higher than along the western edge of the High Cascades.

Hill, B.E. [ed.

1992-10-01T23:59:59.000Z

245

Finite-size scaling of two-point statistics and the turbulent energy cascade generators  

Science Journals Connector (OSTI)

Within the framework of random multiplicative energy cascade models of fully developed turbulence, finite-size-scaling expressions for two-point correlators and cumulants are derived, taking into account the observationally unavoidable conversion from an ultrametric to an Euclidean two-point distance. The comparison with two-point statistics of the surrogate energy dissipation, extracted from various wind tunnel and atmospheric boundary layer records, allows an accurate deduction of multiscaling exponents and cumulants, even at moderate Reynolds numbers for which simple power-law fits are not feasible. The extracted exponents serve as input for parametric estimates of the probabilistic cascade generator. Various cascade generators are evaluated.

Jochen Cleve; Thomas Dziekan; Jrgen Schmiegel; Ole E. Barndorff-Nielsen; Bruce R. Pearson; Katepalli R. Sreenivasan; Martin Greiner

2005-02-28T23:59:59.000Z

246

Energy spectrum of cascade showers generated in water by near-horizontal muons  

Science Journals Connector (OSTI)

We discuss measuring cascade shower energy using the NEVOD Cherenkov water detector with ... applied to showers generated by near-horizontal high-energy muons selected using the DECOR coordinate detector deployed...

S. S. Khokhlov; N. S. Barbashina

2013-05-01T23:59:59.000Z

247

Summary of activities in the Working Group on QCD Cascades of the HERA Monte Carlo workshop  

E-Print Network [OSTI]

We summarize the activities in working group 10 concerned with QCD cascades, and find that although much work still needs to be done, much progress was made during this workshop in understanding the merits and deficiencies of different programs.

Nick Brook; Leif Lonnblad

1999-08-16T23:59:59.000Z

248

Summary of activities in the Working Group on QCD Cascades of the HERA Monte Carlo workshop  

E-Print Network [OSTI]

We summarize the activities in working group 10 concerned with QCD cascades, and find that although much work still needs to be done, much progress was made during this workshop in understanding the merits and deficiencies of different programs.

Brook, N; Brook, Nick; Lonnblad, Leif

1999-01-01T23:59:59.000Z

249

Improving the aerodynamic efficiency of blade profile cascade used in a cooled turbine  

Science Journals Connector (OSTI)

Good effect from using rotor blade cascades, the pressure sides profile of which has a bend near the trailing edge at an angle of no larger than 15, is confirmed from the results of experimental studies.

B. I. Mamaev; M. R. Valeev

2010-09-01T23:59:59.000Z

250

Dynamical Distribution of Capacities Strategy for Suppressing Cascading Failure in Power Grid  

Science Journals Connector (OSTI)

This paper studies the suppressing effect of Dynamical distribution of capacities (DDC) strategy in cascading failure of power grid. This strategy is proposed based on load characteristics and transmission method...

Zhi-Juan Jia; Yu Zhang; Cong Feng; Ming-Sheng Hu

2014-01-01T23:59:59.000Z

251

Advanced fault diagnosis techniques and their role in preventing cascading blackouts  

E-Print Network [OSTI]

This dissertation studied new transmission line fault diagnosis approaches using new technologies and proposed a scheme to apply those techniques in preventing and mitigating cascading blackouts. The new fault diagnosis approaches are based on two...

Zhang, Nan

2007-04-25T23:59:59.000Z

252

Finite-State Transducer Cascade to Extract Proper Names in Texts  

Science Journals Connector (OSTI)

This article describes a finite-state cascade for the extraction of person names in texts in French. We extract these proper names in order to categorize and to cluster texts with them. After a finite-state pr...

Nathalie Friburger; 1]Denis Maurel

2002-01-01T23:59:59.000Z

253

Good Cascade Impactor Practice (GCIP) and Considerations for In-Use Specifications  

Science Journals Connector (OSTI)

The multi-stage cascade impactor (CI) is widely used to determine aerodynamic particle size distributions (APSDs) of orally inhaled products. Its size-fractionating capability depends primarily on the size of ...

S. C. Nichols; J. P. Mitchell; C. M. Shelton; D. L. Roberts

2013-03-01T23:59:59.000Z

254

A cascaded photonic crystal fiber MachZehnder interferometer formed by extra electric arc discharges  

Science Journals Connector (OSTI)

In this paper, a cascaded MachZehnder interferometer based on a photonic crystal fiber is reported. It is demonstrated that by applying a small dose of extra arc discharge to the photonic crystal fiber sensin...

Y. Geng; X. Li; X. Tan; Y. Deng; Y. Yu

2011-03-01T23:59:59.000Z

255

Observation of cascaded two-photon-induced transitions between fluxoid states of a SQUID  

E-Print Network [OSTI]

We present evidence for transitions between fluxoid wells of a SQUID due to cascaded, two-photon processes. Such transitions are evidenced by an anomalous dependence on the transition rate from the one-photon resonant level ...

Han, Siyuan; Lukens, J. E.; Rouse, R.

2000-02-07T23:59:59.000Z

256

The Impact of the Topology on Cascading Failures in Electric Power Grids  

E-Print Network [OSTI]

Cascading failures are one of the main reasons for blackouts in power transmission grids. The topology of a power grid, together with its operative state determine, for the most part, the robustness of the power grid against cascading failures. Secure electrical power supply requires, together with careful operation, a robust design of the electrical power grid topology. This paper investigates the impact of a power grid topology on its robustness against cascading failures. Currently, the impact of the topology on a grid robustness is mainly assessed by using purely topological approaches that fail to capture the essence of electric power flow. This paper proposes a metric, the effective graph resistance, that relates the topology of a power grid to its robustness against cascading failures by deliberate attacks, while also taking the fundamental characteristics of the electric power grid into account such as power flow allocation according to Kirchoff Laws. Experimental verification shows that the proposed ...

Ko, Yakup; Van Mieghem, Piet; Kooij, Robert E; Brazier, Frances M T

2014-01-01T23:59:59.000Z

257

Numerical calculations of cosmic ray cascade in the Earth's atmosphere Results for nucleon spectra  

E-Print Network [OSTI]

such as production of cosmogenic nuc- lides, radiation dosimetry and single event upsets in the microelec- tronics [1 in the atmosphere. Some of the particles produced in the cascade can reach the Earth's surface and induce nuclear

258

Quantum-cascade laser photoacoustic detection of methane emitted from natural gas powered engines  

Science Journals Connector (OSTI)

In this work we present a laser photoacoustic arrangement for the detection of the important greenhouse gas methane. A quantum-cascade laser and a differential photoacoustic cell were ... tested in the detection ...

M. V. Rocha; M. S. Sthel; M. G. Silva; L. B. Paiva; F. W. Pinheiro

2012-03-01T23:59:59.000Z

259

Mixed Refrigerant Cascade Liquefiers for Natural GasDesign and Optimization  

Science Journals Connector (OSTI)

This paper describes the development of highly flexible calculation methods and computer programs to deal with the complex problems encountered in the design of Mixed Refrigerant Cascade (MRC) plants. The relativ...

D. T. Linnett; K. C. Smith

1995-01-01T23:59:59.000Z

260

The damped natural oscillations of a gas flowing past a cascade of flat plates  

Science Journals Connector (OSTI)

We solve the problem of the natural oscillations of a gas flowing past a cascade of flat plates under the Joukowsky-Chaplygin ... case part of the energy of the oscillating gas is consumed in the formation of a ....

V. B. Kurzin

Note: This page contains sample records for the topic "region cascades gea" 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

SIMULATION MODELING OF AN ENHANCED LOW-EMISSION SWIRL-CASCADE BURNER  

SciTech Connect (OSTI)

Based on the physical and computational models outlined in the previous technical progress reports, Natural gas jet diffusion flames in baseline, cascade, swirl, and swirlcascade burners were numerically modeled. The thermal, composition, and flow (velocity) fields were simulated. The temperature, CO{sub 2} and O{sub 2} concentrations, as well as the axial and radial velocity profiles were computed and analyzed. The numerical results showed that swirl and cascade burners have a more efficient fuel/air mixing, a shorter flame, and a lower NOx emission levels, compared to the baseline case. The results also revealed that the optimal configurations of the cascaded and swirling flames have not produced an improved performance when combined together in a ''swirl-cascade burner''.

Ala Qubbaj

2004-04-01T23:59:59.000Z

262

Label Free Mid-IR Photothermal Imaging of Bird Brain With Quantum Cascade Laser  

Science Journals Connector (OSTI)

Label free mid-infrared photothermal imaging on bird brain slices is presented. The Amide-I vibrational band is excited by a quantum cascade laser and an Er:doped fiber measures the...

Mertiri, Alket; Totachawattana, Atcha; Liu, Hui; Hong, Mi K; Gardner, Tim; Sander, Michelle Y; Erramilli, Shyamsunder

263

Active hyperspectral imaging using a quantum cascade laser (QCL) array and digital-pixel focal  

E-Print Network [OSTI]

, D. L. Sivco, and A. Y. Cho, "Quantum cascade lasers," Phys. Today 55(5), 34 (2002). 13. Daylight Solutions, Inc., www.daylightsolutions.com; Block Engineering LLC, www.blockeng.com. 14. B. G. Lee, M. A

Capasso, Federico

264

Optimization of an External Cavity Quantum Cascade Laser for Chemical Sensing Applications  

SciTech Connect (OSTI)

We describe and characterize an external cavity quantum cascade laser designed for detection of multiple airborne chemicals, and used with a compact astigmatic Herriott cell for sensing of acetone and hydrogen peroxide.

Phillips, Mark C.; Bernacki, Bruce E.; Taubman, Matthew S.; Cannon, Bret D.; Schiffern, John T.; Myers, Tanya L.

2010-03-01T23:59:59.000Z

265

Design of Laser Transition Oscillator Strength for THz Quantum Cascade Lasers  

Science Journals Connector (OSTI)

The density matrix based model is employed to design number of THz quantum cascade lasers with various laser oscillator strengths. The optimum oscillator strength varies between 0.35...

Fathololoumi, Saeed; Dupont, Emmanuel; Laframboise, Sylvain R; Wasilewski, Zbigniew R; Ban, Dayan; Liu, Hc

266

Pulsed High Duty-Cycle Operation of ? ~ 8m Quantum Cascade Lasers  

Science Journals Connector (OSTI)

We report on high duty-cycle pulsed and burst-mode operation of ?~8m quantum cascade lasers under ambient conditions for photo-acoustic spectroscopy. An optimum in average optical...

Ko, Tiffany; Liu, Zhijun; Gmachl, Claire

267

Recent progress in high precision atmospheric trace gas instruments using mid-infrared quantum cascade lasers  

Science Journals Connector (OSTI)

We report results from high precision spectroscopic instruments for atmospheric trace gases using with mid-IR quantum cascade lasers. Numerous gases can be measured with 1s absorption...

McManus, John B; Zahniser, Mark; Nelson, David; McGovern, Ryan; Agnese, Mike

268

Strain-balanced quantum cascade lasers: influence of growth temperature on interface roughness and laser performance  

Science Journals Connector (OSTI)

Effect of substrate temperature on the performances of quantum cascade lasers operating at 4.6um is presented. Using a density matrix model results for different growth temperatures...

Bismuto, Alfredo; Terazzi, Romain; Beck, Mattias; Faist, Jerome

269

Spectroscopic detection of hazardous substances using broadband-tunable Quantum Cascade Lasers  

Science Journals Connector (OSTI)

External-Cavity-Quantum Cascade Lasers are attractive sources for mid-infrared spectroscopy. We demonstrate the possibilities offered by EC-QCLs by two examples: Standoff detection of...

Hugger, Stefan; Fuchs, Frank; Jarvis, Jan; Yang, Quankui; Driad, Rachid; Bronner, Wolfgang; Aidam, Rolf; Ostendorf, Ralf; Wagner, Joachim

270

Electron microscopy of GaAs/AlGaAs quantum cascade laser  

Science Journals Connector (OSTI)

The quantum cascade laser (QCL) is based on a different principle comparing to bipolar semiconductor lasers, because it uses only one type of ... electrons and therefore is called an unipolar laser.

A. ?aszcz; J. Ratajczak; A. Czerwinski

2008-01-01T23:59:59.000Z

271

Near-Infrared Laser Pulse Induced Amplitude Modulation of Terahertz Quantum Cascade Lasers  

Science Journals Connector (OSTI)

We have demonstrated amplitude modulation of terahertz quantum cascade lasers by means of the injection of near-infrared laser pulses. Injected 770nm and 1350nm laser pulses both...

Sakasegawa, Yohei; Saito, Shingo; Sekine, Norihiko; Ashida, Masaaki; Hosako, Iwao

272

Superconducting Microbolometer with Microsecond Time Constant Coupled to Quantum Cascade Lasers  

Science Journals Connector (OSTI)

A superconducting bolometer with an on-chip lithographic terahertz antenna has been illuminated by two quantum cascade lasers operating at 2.5 and 4.4 THz to be used for wide dynamic...

Cibella, Sara; Ortolani, Michele; Leoni, Roberto; Torrioli, Guido; Tredicucci, Alessandro; Mahler, L; Xu, Ji-Hua; Beere, H E; Ritchie, D A

273

Gain to Absorption Ratio of Self-Induced Transparency Modelocked Quantum Cascade Lasers  

Science Journals Connector (OSTI)

A model to calculate the gain to absorption ratio of self-induced transparency modelocked quantum cascade lasers is presented and then used to find the gain to absorbing periods ratio...

Talukder, Muhammad; Menyuk, Curtis

274

Development of a compact quantum cascade laser spectrometer for field measurements of CO2 isotopes  

Science Journals Connector (OSTI)

We report the development of a field-deployable, pulsed quantum cascade laser spectrometer. The instrument is designed to measure...13C/12C isotopic ratio in the CO2 released from volcanic vents. Specific 12CO2 a...

D. Weidmann; G. Wysocki; C. Oppenheimer; F.K. Tittel

2005-02-01T23:59:59.000Z

275

Intra-pulse beam steering in a mid-infrared quantum cascade laser  

Science Journals Connector (OSTI)

The intra-pulse measurements of the beam steering in an AlGaAs/GaAs quantum cascade laser are presented in this paper. The experimental ... theoretical model. The near field of the laser radiation is calculated a...

Emilia Pruszy?ska-Karbownik; Kazimierz Regi?ski

2014-08-01T23:59:59.000Z

276

Lateral Current Density Distribution and Spatial Hole Burning in Quantum Cascade Lasers  

Science Journals Connector (OSTI)

We have investigated non-uniformity of the lateral current density and lateral hole burning in Quantum Cascaded lasers, e.g., the current density in the mode center is 1.8 times that...

Huang, Xue; Dikmelik, Yamac; Gmachl, Claire F

277

Hyperspectral microscopy using an external cavity quantum cascade laser and its applications for explosives detection  

SciTech Connect (OSTI)

A hyperspectral infrared microscope using external cavity quantum cascade laser illumination and a microbolometer focal plane array is used to characterize nanogram-scale particles of the explosives RDX, tetryl, and PETN at fast acquisition rates.

Phillips, Mark C.; Suter, Jonathan D.; Bernacki, Bruce E.

2012-04-01T23:59:59.000Z

278

Direct Modulation of Quantum Cascade Lasers for Chirped Laser Dispersion Spectroscopy  

Science Journals Connector (OSTI)

This paper provides an analysis of direct modulation of a quantum cascade laser for applications in chirped laser dispersion spectroscopy (CLaDS). The developed laser model is used to...

Hangauer, Andreas; Spinner, Georg; Nikodem, Michal; Wysocki, Gerard

279

Sensitive detection of acrolein and acrylonitrile with a pulsed quantum-cascade laser  

Science Journals Connector (OSTI)

We report on spectroscopic measurements of acrolein and acrylonitrile at atmospheric pressure using a pulsed distributed feedback quantum-cascade laser in combination with intra- and inter-pulse...?1. In the inte...

J. Manne; A. Lim; J. Tulip; W. Jger

2012-05-01T23:59:59.000Z

280

A multi-tiered memetic multiobjective evolutionary algorithm for the design of quantum cascade lasers  

Science Journals Connector (OSTI)

Recent advances in quantum cascade lasers (QCLs) have enabled their use as (tunable) emission sources for chemical and biological spectroscopy, as well as allowed their demonstration in applications in medical diagnostics and potential homeland security ...

Mark P. Kleeman; Gary B. Lamont; Adam Cooney; Thomas R. Nelson

2007-03-01T23:59:59.000Z

Note: This page contains sample records for the topic "region cascades gea" 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

Sub-ppb detection of formaldehyde with cantilever enhanced photoacoustic spectroscopy using quantum cascade laser source  

Science Journals Connector (OSTI)

A novel cantilever enhanced photoacoustic spectrometer with mid-infrared quantum cascade laser was applied for selective and sensitive formaldehyde...2O) gas measurement. The spectrum of formaldehyde was measured...

C. B. Hirschmann; J. Lehtinen; J. Uotila; S. Ojala; R. L. Keiski

2013-06-01T23:59:59.000Z

282

The Influence of Doping on the Performance of Terahertz Quantum-Cascade-Lasers  

Science Journals Connector (OSTI)

We present the effects of the doping concentration on a set of terahertz quantum-cascade-lasers emitting around 2.75 THz. The threshold current density decreases linearly with the...

Benz, Alexander; Fasching, Gernot; Andrews, Aaron Maxwell; Unterrainer, Karl; Roch, Tomas; Schrenk, Werner; Strasser, Gottfried

283

Quantum Cascade Laser Technology for the Ultrasensitive Detection of Low-Level Nitric Oxide  

Science Journals Connector (OSTI)

Several spectroscopic methods based on mid-infrared quantum cascade lasers for the ultrasensitive detection of nitric oxide ... the most effective techniques, i.e., laser absorption spectroscopy, cavity-enhanced ...

Angela Elia; Pietro Mario Lugar; Cinzia Di Franco; Vincenzo Spagnolo

2011-01-01T23:59:59.000Z

284

Quantum cascade laser-based carbon monoxide detection on a second time scale from human breath  

Science Journals Connector (OSTI)

We present three different detection schemes for measuring carbon monoxide (CO) in direct absorption using a thermoelectrically cooled, distributed-feedback pulsed quantum cascade (qc) laser operating between 217...

B.W.M. Moeskops; H. Naus; S.M. Cristescu; F.J.M. Harren

2006-03-01T23:59:59.000Z

285

Synthesis of Marine Polycyclic Polyethers via Endo-Selective Epoxide-Opening Cascades  

E-Print Network [OSTI]

The proposed biosynthetic pathways to ladder polyethers of polyketide origin and oxasqualenoids of terpenoid origin share a dramatic epoxide-opening cascade as a key step. Polycyclic structures generated in these biosynthetic ...

Vilotijevic, Ivan

286

Surface-emitting distributed feedback terahertz quantum-cascade phase-locked laser arrays  

E-Print Network [OSTI]

A new approach to achieve high-power, symmetric beam-pattern, single-mode THz emission from metal-metal waveguide quantum-cascade laser is proposed and implemented. Several surface-emitting distributed feedback terahertz ...

Kao, Tsung-Yu

2009-01-01T23:59:59.000Z

287

High-Power Thermoelectrically-Cooled and Uncooled Mid-Wave Infrared Quantum Cascade Lasers  

Science Journals Connector (OSTI)

We present high performance thermoelectrically-cooled and uncooled mid-wave infrared (?=4.6 ?m) quantum cascade lasers with continuous-wave output power of 2.9 W and 1 W at room...

Maulini, Richard; Lyakh, Arkadiy; Tsekoun, Alexei; Pflugl, Christian; Diehl, Laurent; Capasso, Federico; Patel, Kumar

288

Quantum mechanical model of the upper bounds of the cascading contribution to the second hyperpolarizability  

SciTech Connect (OSTI)

Microscopic cascading of second-order nonlinearities between two molecules has been proposed to yield an enhanced third-order molecular nonlinear-optical response. In this contribution, we investigate the two-molecule cascaded second hyperpolarizability and show that it will never exceed the fundamental limit of a single molecule with the same number of electrons as the two-molecule system. We show the apparent divergence behavior of the cascading contribution to the second hyperpolarizability vanishes when properly taking into account the intermolecular interactions. Although cascading can never lead to a larger nonlinear-optical response than a single molecule, it provides alternative molecular design configurations for creating materials with large third-order susceptibilities that may be difficult to design into a single molecule.

Dawson, Nathan J.; Anderson, Benjamin R.; Schei, Jennifer L.; Kuzyk, Mark G. [Department of Physics and Astronomy, Washington State University, Pullman, Washington 99164-2814 (United States)

2011-10-15T23:59:59.000Z

289

Heat Flow From Four New Research Drill Holes In The Western Cascades...  

Open Energy Info (EERE)

Four New Research Drill Holes In The Western Cascades, Oregon, Usa Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Heat Flow From Four New...

290

A Cascade-Type Global Energy Conversion Diagram Based on WaveMean Flow Interactions  

Science Journals Connector (OSTI)

A cascade-type energy conversion diagram is proposed for the purpose of diagnosing the atmospheric general circulation based on wavemean flow interactions. Mass-weighted isentropic zonal means facilitate the expression of nongeostrophic wave ...

Sachiyo Uno; Toshiki Iwasaki

2006-12-01T23:59:59.000Z

291

Cascade Model of an Anomaly in Blazar Spectra at Very High Energy  

E-Print Network [OSTI]

It is well known that the effect of gamma-ray absorption on extragalactic background light (EBL) is weakly expressed in the spectra of some blazars. It is shown that a secondary component generated by electromagnetic cascades might considerably decrease the statistical significance of this anomaly. Observational results indicate the existence of the cascade component in the spectra of extragalactic gamma-ray sources, thus supporting the proposed model.

Dzhatdoev, Timur

2015-01-01T23:59:59.000Z

292

Molecular-beam epitaxy growth and characterization of mid-infrared quantum cascade laser structures  

Science Journals Connector (OSTI)

The development of molecular-beam epitaxy (MBE) of GaAs/AlGaAs heterostructures, used for fabrication of ~9?m quantum cascade lasers (QCLs), is reported. The X-ray diffractometry (XRD) structural characterization, as an integral part of this process, ... Keywords: GaAs/AlGaAs lasers, Intersubband transitions, Mid-infrared, Molecular-beam epitaxy, Quantum cascade laser, Unipolar devices

Kamil Kosiel; Justyna Kubacka-Traczyk; Piotr Karbownik; Anna Szerling; Jan Muszalski; Maciej Bugajski; Przemek Romanowski; Jaros?aw Gaca; Marek Wjcik

2009-03-01T23:59:59.000Z

293

Gamma-ray cascade transitions from resonant neutron capture in Cd-111 and Cd-113  

SciTech Connect (OSTI)

A neutron-capture experiment on {sup nat}Cd has been carried out at DANCE. Multiple-fold coincidence {gamma}-ray spectra have been collected from J=0, 1 resonances in {sup 111}Cd and {sup 113}Cd. The cascades ending at the ground state can be described by the SLO model while the cascades ending at the 2+ states are better reproduced by the mixed SLO+KMF model.

Rusev, Gencho Y. [Los Alamos National Laboratory

2012-08-27T23:59:59.000Z

294

The critical tension in the Cascading DGP model  

E-Print Network [OSTI]

We study the behaviour of weak gravitational fields in the 6D Cascading DGP model using a bulk-based approach. To deal with the ambiguity in the thin limit of branes of codimension higher than one, we consider a specific regularization of the internal structure of the branes where the 5D brane can be considered thin with respect to the 4D one. We consider the solutions corresponding to pure tension sources on the 4D brane, and study perturbations at first order around these background solutions. We adopt a 4D scalar-vector-tensor decomposition, and focus on the scalar sector of perturbations. We show that, in a suitable 4D limit, the trace part of the 4D metric perturbations obeys a decoupled equation which suggests that it is a ghost for background tensions smaller than a critical tension, while it is a healthy field otherwise. We give a geometrical interpretation of the existence of the critical tension and of the reason why the relevant field is a ghost or not depending on the background tension. We howeve...

Sbis, Fulvio

2014-01-01T23:59:59.000Z

295

The conservative cascade of kinetic energy in compressible turbulence  

E-Print Network [OSTI]

The physical nature of compressible turbulence is of fundamental importance in a variety of astrophysical settings. We present the first direct evidence that mean kinetic energy cascades conservatively beyond a transitional "conversion" scale-range despite not being an invariant of the compressible flow dynamics. We use high-resolution three-dimensional simulations of compressible hydrodynamic turbulence on $512^3$ and $1024^3$ grids. We probe regimes of forced steady-state isothermal flows and of unforced decaying ideal gas flows. The key quantity we measure is pressure dilatation cospectrum, $E^{PD}(k)$, where we provide the first numerical evidence that it decays at a rate faster than $k^{-1}$ as a function of wavenumber. This is sufficient to imply that mean pressure dilatation acts primarily at large-scales and that kinetic and internal energy budgets statistically decouple beyond a transitional scale-range. Our results suggest that an extension of Kolmogorov's inertial-range theory to compressible turbulence is possible.

Hussein Aluie; Shengtai Li; Hui Li

2011-07-28T23:59:59.000Z

296

The Energy Cascade from Warm Dark Matter Decays  

E-Print Network [OSTI]

We use a set of Monte Carlo simulations to follow the cascade produced by a primary electron of energy E_in in the intergalactic medium. We choose E_in=3-10 keV as expected from the decay of one of the most popular Warm Dark Matter (WDM) candidates, sterile neutrinos. Our simulation takes into account processes previously neglected such as free-free interactions with ions and recombinations and uses the best available cross sections for collisional ionizations and excitations with H and He and for electron-electron collisions. We precisely derive the fraction of the primary electron energy that heats the gas, ionizes atoms and produces line and continuum photons as a function of the ionization fraction. Handy fitting formulae for all the above energy depositions are provided. By keeping track of the individual photons we can distinguish between photons in the Ly-alpha resonance and those with energy E gas. This separation is important because a Ly-alpha background can heat or cool the gas depending on the nature of the photons, and can have effects on the 21 cm radiation emitted by neutral H, which will probably become detectable at z > 6 in the near future by the next generation radio interferometers.

M. Valds; A. Ferrara

2008-03-04T23:59:59.000Z

297

The conservative cascade of kinetic energy in compressible turbulence  

E-Print Network [OSTI]

The physical nature of compressible turbulence is of fundamental importance in a variety of astrophysical settings. We present the first direct evidence that mean kinetic energy cascades conservatively beyond a transitional "conversion" scale-range despite not being an invariant of the compressible flow dynamics. We use high-resolution three-dimensional simulations of compressible hydrodynamic turbulence on $512^3$ and $1024^3$ grids. We probe regimes of forced steady-state isothermal flows and of unforced decaying ideal gas flows. The key quantity we measure is pressure dilatation cospectrum, $E^{PD}(k)$, where we provide the first numerical evidence that it decays at a rate faster than $k^{-1}$ as a function of wavenumber. This is sufficient to imply that mean pressure dilatation acts primarily at large-scales and that kinetic and internal energy budgets statistically decouple beyond a transitional scale-range. Our results suggest that an extension of Kolmogorov's inertial-range theory to compressible turbu...

Aluie, Hussein; Li, Hui

2011-01-01T23:59:59.000Z

298

Emission and Propagation Properties of Midinfrared Quantum Cascade Lasers  

SciTech Connect (OSTI)

We report divergence, astigmatism and M2 measurements of quantum cascade lasers (QCL) with an emission wavelength of 8.77?m. Emission profiles from the QCL facet showed divergence angles of 62 and 32 FWHM 2 for the fast and slow axes, respectively. The observation of far field structure superimposed on the fast axes profiles was attributed to the position of the QCL die with respect to the edge of the laser submount, emphasizing the need for careful placement. Two diffraction-limited Germanium aspheric microlenses were designed and fabricated to efficiently collect, collimate, and focus QCL emission. A confocal system comprised of these lenses was used to measure the beam propagation figure of merit (M2) yielding 1.8 and 1.2 for the fast and slow axes, respectively. Astigmatism at the exit facet was calculated to be about 4 ?m, or less than half a wave. To the best of our knowledge, this is the first experimental measurement of astigmatism and M2 reported for mid-IR QCLs.

Krishnaswami, Kannan; Bernacki, Bruce E.; Cannon, Bret D.; Ho, Nicolas; Anheier, Norman C.

2008-02-15T23:59:59.000Z

299

Recent developments of the cascade-exciton model of nuclear reactions  

SciTech Connect (OSTI)

Recent developments of the Cascade-Exciton Model (CEM) of nuclear reactions are described. The improved cascade-exciton model as implemented in the code CEM97 differs from the CEM95 version by incorporating new approximations for the elementary cross sections used in the cascade, using more precise values for nuclear masses and pairing energies, using corrected systematics for the level-density parameters, and several other refinements. We have improved algorithms used in many subroutines, decreasing the computing time by up to a factor of 6 for heavy targets. We describe a number of further improvements and changes to CEM97, motivated by new data on isotope production measured at GSI. This leads us to CEM2k, a new version of the CEM code. CEM2k has a longer cascade stage, less preequilibrium emission, and evaporation from more highly excited compound nuclei compared to earlier versions. CEM2k also has other improvements and allows us to better model neutron, radionuclide, and gas production in ATW spallation targets. The increased accuracy and predictive power of the code CEM2k are shown by several examples. Further necessary work is outlined. KEYWORDS: Intranuclear cascade, preequilibrium, evaporation, and fission reactions, Monte Carlo simulations, cascade-exciton model, particle spectra, spallation and fission cross sections, GSI data

Mashnik, S. G. (Stepan G.); Sierk, A. J. (Arnold J.)

2001-01-01T23:59:59.000Z

300

Astrophysical Gyrokinetics: Kinetic and Fluid Turbulent Cascades In Magentized Weakly Collisional Plasmas  

SciTech Connect (OSTI)

This paper presents a theoretical framework for understanding plasma turbulence in astrophysical plasmas. It is motivated by observations of electromagnetic and density fluctuations in the solar wind, interstellar medium and galaxy clusters, as well as by models of particle heating in accretion disks. All of these plasmas and many others have turbulentmotions at weakly collisional and collisionless scales. The paper focuses on turbulence in a strong mean magnetic field. The key assumptions are that the turbulent fluctuations are small compared to the mean field, spatially anisotropic with respect to it and that their frequency is low compared to the ion cyclotron frequency. The turbulence is assumed to be forced at some system-specific outer scale. The energy injected at this scale has to be dissipated into heat, which ultimately cannot be accomplished without collisions. A kinetic cascade develops that brings the energy to collisional scales both in space and velocity. The nature of the kinetic cascade in various scale ranges depends on the physics of plasma fluctuations that exist there. There are four special scales that separate physically distinct regimes: the electron and ion gyroscales, the mean free path and the electron diffusion scale. In each of the scale ranges separated by these scales, the fully kinetic problem is systematically reduced to a more physically transparent and computationally tractable system of equations, which are derived in a rigorous way. In the "inertial range" above the ion gyroscale, the kinetic cascade separates into two parts: a cascade of Alfvenic fluctuations and a passive cascade of density and magnetic-fieldstrength fluctuations. The former are governed by the Reduced Magnetohydrodynamic (RMHD) equations at both the collisional and collisionless scales; the latter obey a linear kinetic equation along the (moving) field lines associated with the Alfvenic component (in the collisional limit, these compressive fluctuations become the slow and entropy modes of the conventional MHD). In the "dissipation range" below ion gyroscale, there are again two cascades: the kinetic-Alfven-wave (KAW) cascade governed by two fluid-like Electron Reduced Magnetohydrodynamic (ERMHD) equations and a passive cascade of ion entropy fluctuations both in space and velocity. The latter cascade brings the energy of the inertial-range fluctuations that was Landau-damped at the ion gyroscale to collisional scales in the phase space and leads to ion heating. The KAWenergy is similarly damped at the electron gyroscale and converted into electron heat. Kolmogorov-style scaling relations are derived for all of these cascades. The relationship between the theoretical models proposed in this paper and astrophysical applications and observations is discussed in detail.

A.A. Schekochihin, S.C. Cowley, W. Dorland, G.W. Hammett, G.G. Howes, E. Quataert, and T. Tatsuno

2009-04-23T23:59:59.000Z

Note: This page contains sample records for the topic "region cascades gea" 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

The critical tension in the Cascading DGP model  

E-Print Network [OSTI]

We study the behaviour of weak gravitational fields in the 6D Cascading DGP model using a bulk-based approach. To deal with the ambiguity in the thin limit of branes of codimension higher than one, we consider a specific regularization of the internal structure of the branes where the 5D brane can be considered thin with respect to the 4D one. We consider the solutions corresponding to pure tension sources on the 4D brane, and study perturbations at first order around these background solutions. We adopt a 4D scalar-vector-tensor decomposition, and focus on the scalar sector of perturbations. We show that, in a suitable 4D limit, the trace part of the 4D metric perturbations obeys a decoupled equation which suggests that it is a ghost for background tensions smaller than a critical tension, while it is a healthy field otherwise. We give a geometrical interpretation of the existence of the critical tension and of the reason why the relevant field is a ghost or not depending on the background tension. We however find a value of the critical tension which is different from the one already found in the literature. Differently from the results in the literature, our analysis implies that, choosing the background tension suitably, we can construct ghost-free models for any value of the free parameters of the theory. We suggest that the difference lies in the procedure used to evaluate the pillbox integration across the codimension-2 brane. We confirm the validity of our analysis by performing numerically the integration in a particular case where the solution inside the thick cod-2 brane is known exactly. We stress that the singular structure of the perturbation fields in the nested branes set-ups is very subtle, and that great care has to be taken when deriving the codimension-2 junction conditions.

Fulvio Sbisa'; Kazuya Koyama

2014-09-01T23:59:59.000Z

302

Soliton compression to few-cycle pulses with a high quality factor by engineering cascaded quadratic nonlinearities  

Science Journals Connector (OSTI)

We propose an efficient approach to improve few-cycle soliton compression with cascaded quadratic nonlinearities by using an engineered multi-section structure of the nonlinear...

Zeng, Xianglong; Guo, Hairun; Zhou, Binbin; Bache, Morten

2012-01-01T23:59:59.000Z

303

Improving Soliton Compression Quality with Cascaded Nonlinearities by Engineered Multi-section Quasi-phase-matching Design  

Science Journals Connector (OSTI)

In few-cycle soliton generation with large compression factors using cascaded nonlinearities the pulse quality can be improved by engineering quasi-phase-matching structures. The...

Zeng, Xianglong; Guo, Hairun; Zhou, Binbin; Bache, Morten

304

Isotopic Ratio Measurements of Atmospheric Carbon Dioxide Using a 4.3 ?m Pulsed Quantum Cascade Laser  

Science Journals Connector (OSTI)

We report CO2 isotopic ratios (13C, 18O) measured in air using a pulsed quantum cascade laser at 2310 cm-1. Performance is...

Nelson, David; McManus, John B; Zahniser, Mark S; Tuzson, Bela; Emmenegger, Lukas

305

Time-Resolved Measurements of Near-Infrared Pulse Induced Ultrafast Optical Modulation of Quantum Cascade Lasers  

Science Journals Connector (OSTI)

We temporally resolve ultrafast modulation of quantum cascade lasers (QCLs) using a near-infrared pump mid-infrared probe technique. We compare interband and intersubband transition...

Cai, Hong; Liu, Sheng; Lalanne, Elaine; Guo, Dingkai; Chen, Xing; Wang, Xiaojun; Choa, Fow-Sen; Johnson, Anthony M

306

CAPITAL REGION  

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

t 09/20/07 15:28 FAX 301 903 4656 t 09/20/07 15:28 FAX 301 903 4656 CAPITAL REGION 0 j002 SDOE F 1325.8 (8-89) EFG (0790) Energy United States Government Department of Energy Memorandum DATE. September 18, 2007 Audit Report No.: OAS-L-07-23 REPLY TO: IG-34 (A07TG036) SUBJECT: Evaluation of "The Federal Energy Regulatory Commission's Cyber Security Program-2007" TO: Chairman, Federal Energy Regulatory Commission The purpose of this report is to inform you of the results o Four evaluation of the Federal Energy Regulatory Commission's (Commission) cyber security program. The evaluation was initiated in May 2007, and our fieldwork was conducted through September 2007. Our methodology is described in the attachment to this report. . INTRODUCTION AND OBJECTIVE The Commission reports that it is constantly improving thl stability, reliability, and

307

A Novel Integrated TPV Power Generation System Based on a Cascaded Radiant Burner  

Science Journals Connector (OSTI)

A cascaded radiant burner has been developed and based on this burner a novel integrated TPV system has been built. In this system low bandgap GaSb cells and silicon concentrator solar cells are employed integratedly. The unique cascaded radiant burner consists of two different radiators which cascade?emit two streams of radiation with different spectra. The two different radiators are arranged in tandem with their surface temperatures being different as well. Two streams of radiation output are matched respectively to the bandgaps of silicon cells and GaSb cells. Thus one stream of radiation output illuminates silicon concentrator solar cells while the other drives low bandgap GaSb cells in the integrated system. In this work the combustion performance of the cascaded radiant burner was investigated at varying degrees of exhaust heat recuperation. The electrical output characteristics of both silicon concentrator solar cells and GaSb cells in the gas combustion?driven TPV system were measured under various operating conditions. It is shown that this innovative design considerably increases the TPV system efficiency due to the cascaded utilization of heat released during natural gas combustion and the optimized thermal management.

K. Qiu; A. C. S. Hayden

2004-01-01T23:59:59.000Z

308

First search for extraterrestrial neutrino-induced cascades with IceCube  

SciTech Connect (OSTI)

We report on the first search for extraterrestrial neutrino-induced cascades in IceCube.The analyzed data were collected in the year 2007 when 22 detector strings were installed and operated. We will discuss the analysis methods used to reconstruct cascades and to suppress backgrounds. Simulated neutrino signal events with a E-2 energy spectrum, which pass the background rejection criteria, are reconstructed with a resolution Delta(log E) ~;; 0.27 in the energy range from ~;; 20 TeV to a few PeV. We present the range of the diffuse flux of extra-terrestrial neutrinos in the cascade channel in IceCube within which we expect to be able to put a limit.

IceCube Collaboration; Kiryluk, Joanna

2009-05-22T23:59:59.000Z

309

Soliton compression to high-quality few-cycle pulses by engineering cascaded quadratic nonlinearities  

E-Print Network [OSTI]

We propose an efficient approach to improve few-cycle soliton compression with cascaded quadratic nonlinearities by using an engineered multi-section structure of the nonlinear crystal. By exploiting engineering of the cascaded quadratic nonlinearities, in each section soliton compression with a low effective order is realized, and high-quality few-cycle pulses with large compression factors are feasible. Each subsequent section is designed so that the compressed pulse exiting the previous section experiences an overall effective self-defocusing cubic nonlinearity corresponding to a modest soliton order, which is kept larger than unity to ensure further compression. This is done by increasing the cascaded quadratic nonlinearity in the new section with an engineered reduced residual phase mismatch. The low soliton orders in each section ensure excellent pulse quality and high efficiency. Numerical results show that compressed pulses with less than three-cycle duration can be achieved even when the compression ...

Zeng, Xianglong; Zhou, Binbin; Bache, Morten

2012-01-01T23:59:59.000Z

310

Cascaded H-bridge inverter motor drives for hybrid electric vehicle applications  

Science Journals Connector (OSTI)

This paper presents the asymmetric cascaded H-bridge multilevel inverter for electric vehicles (EV) and hybrid electric vehicles (HEV) applications. Currently available power inverter systems for HEVs use a DC-DC boost converter to boost the battery voltage for a traditional three-phase inverter. The present HEV drive inverters have low power density, are expensive, and have low efficiency because they need a bulky inductor. Asymmetric cascaded H-bridge multilevel inverter design for EV and HEV applications without the use of inductors to output a boosted AC voltage is proposed in this paper. Traditionally, each H-bridge needs a DC power supply having equal values of DC power sources. The proposed design uses the asymmetric cascaded multilevel inverter using non-equal DC power sources based on specified ratios. A fundamental switching scheme is used to do modulation control and to produce a seven-level phase voltage.

P. Renuga; T. Prathiba

2012-01-01T23:59:59.000Z

311

An experimental and computational study of transonic three-dimensional flow in a turbine cascade  

SciTech Connect (OSTI)

Detailed experimental measurements of the flow in a cascade of turbine rotor blades with a nonplanar end wall are reported. The cascade geometry was chosen to model as closely as possible that of a H.P. gas turbine rotor blade. The blade section is designed for supersonic flow with an exit Mach number of 1.15 and the experiments covered a range of exit Mach numbers from 0.7-1.2. Significant three-dimensional effects were observed and the origin of these is discussed. The measurements are compared with data for the same blade section in a two-dimensional cascade and also with the predictions of two different fully three-dimensional inviscid flow calculation methods. It is found that both these calculations predict the major threedimensional effects on the flow correctly.

Camus, J.J.; Denton, J.D.; Scrivener, C.T.J.; Soulis, J.V.

1984-04-01T23:59:59.000Z

312

Excitonic enhancement of nonradiative energy transfer to bulk silicon with the hybridization of cascaded quantum dots  

SciTech Connect (OSTI)

We report enhanced sensitization of silicon through nonradiative energy transfer (NRET) of the excitons in an energy-gradient structure composed of a cascaded bilayer of green- and red-emitting CdTe quantum dots (QDs) on bulk silicon. Here NRET dynamics were systematically investigated comparatively for the cascaded energy-gradient and mono-dispersed QD structures at room temperature. We show experimentally that NRET from the QD layer into silicon is enhanced by 40% in the case of an energy-gradient cascaded structure as compared to the mono-dispersed structures, which is in agreement with the theoretical analysis based on the excited state population-depopulation dynamics of the QDs.

Yeltik, Aydan; Guzelturk, Burak; Akhavan, Shahab [Department of Physics and Department of Electrical and Electronics Engineering, UNAMInstitute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800 (Turkey)] [Department of Physics and Department of Electrical and Electronics Engineering, UNAMInstitute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800 (Turkey); Ludwig Hernandez-Martinez, Pedro; Volkan Demir, Hilmi, E-mail: volkan@stanfordalumni.org [Department of Physics and Department of Electrical and Electronics Engineering, UNAMInstitute of Materials Science and Nanotechnology, Bilkent University, Ankara 06800 (Turkey); Luminous Center of Excellence for Semiconductor Lighting and Displays, School of Electrical and Electronic Engineering and School of Physical and Mathematical Sciences, Nanyang Technological University, Nanyang Avenue, Singapore 639798 (Singapore)

2013-12-23T23:59:59.000Z

313

SIMULATION MODELING OF AN ENHANCED LOW-EMISSION SWIRL-CASCADE BURNER  

SciTech Connect (OSTI)

The research team was formed. The advanced CFDRC-CHEMKIN software package was installed on a SUN-SPARC dual processor workstation. The literature pertinent to the project was collected. The physical model was set and all parameters and variables were identified. Based on the physical model, the geometric modeling and grid generation processes were performed using the CFD-GEOM (Interactive Geometric Modeling and Grid Generation software). A total number of 11160 cells (248 x 45) were generated to numerically model the baseline, cascaded, swirling, and swirling-cascaded flames. With the cascade being added to the jet, the geometric complexity of the problem increased; which required multi-domain structured grid systems to be connected and matched on the boundaries.

Ala Qubbaj

2003-04-01T23:59:59.000Z

314

ARRA: Reconfiguring Power Systems to Minimize Cascading Failures - Models and Algorithms  

SciTech Connect (OSTI)

Building on models of electrical power systems, and on powerful mathematical techniques including optimization, model predictive control, and simluation, this project investigated important issues related to the stable operation of power grids. A topic of particular focus was cascading failures of the power grid: simulation, quantification, mitigation, and control. We also analyzed the vulnerability of networks to component failures, and the design of networks that are responsive to and robust to such failures. Numerous other related topics were investigated, including energy hubs and cascading stall of induction machines

Dobson, Ian [Iowa State University] [Iowa State University; Hiskens, Ian [Unversity of Michigan] [Unversity of Michigan; Linderoth, Jeffrey [University of Wisconsin-Madison] [University of Wisconsin-Madison; Wright, Stephen [University of Wisconsin-Madison] [University of Wisconsin-Madison

2013-12-16T23:59:59.000Z

315

Gamma-strength functions in 60Ni from two-step cascades following proton capture  

E-Print Network [OSTI]

The two-step cascade method previously used in neutron capture experiments is now applied to a proton capture reaction. The spectrum of two-step cascades populating the first 2+ level of 60Ni has been measured with 59Co(p,2gamma)60Ni reaction. The simulation technique used for the spectrum analysis allows one to reveal the range of possible shapes of both E1 and M1 gamma-strength functions. The low-energy enhancement previously observed in 3He induced reactions is seen to appear in M1 strength functions of 60Ni.

A. Voinov; S. M. Grimes; C. R. Brune; M. Guttormsen; A. C. Larsen; T. N. Massey; A. Schiller; S. Siem

2009-11-10T23:59:59.000Z

316

16 - Microcavities and quantum cascade laser structures based on silicongermanium (SiGe) nanostructures  

Science Journals Connector (OSTI)

Abstract: This chapter discusses two types of Si-based light-emitting devices based on Ge quantum dots in optical microcavities and SiGe quantum cascade (QC) structures. After reviewing various solutions for Si-based light-emitting devices, the chapter describes the method to enhance light emission from Ge dots through embedding them into optical microcavities. It then reviews SiGe quantum cascade laser (QCL) structures on issues of material growth, electroluminescence from SiGe QC structures, n-type SiGe QC structures, and waveguides for SiGe QCLs.

J. Xia; Y. Shiraki; J. Yu

2011-01-01T23:59:59.000Z

317

Four-photon cascade from quadexcitons in a single GaAs quantum dot  

Science Journals Connector (OSTI)

We demonstrate the generation of temporally correlated four photons emitted by the cascade recombination of a quadexciton in a self-assembled GaAs quantum dot (QD) by performing single photon correlation measurements. The cascade decay of the quadexciton involves a triexciton, a biexciton, and an exciton. The emissions of these states are identified in the photoluminescence (PL) spectrum of the QD by cross-correlation measurements. Polarization-resolved cross-correlation measurements show that the polarizations of the four photons are partly correlated. Radiative, nonradiative, and polarization flipping rates in the QD are estimated from the bunching visibilities of the cross-correlation measurements and the PL lifetimes.

Y. Arashida; Y. Ogawa; F. Minami

2011-09-12T23:59:59.000Z

318

hal-00135292,version1-7Mar2007 Photovoltaic Probe of Cavity Polaritons in a Quantum Cascade Structure  

E-Print Network [OSTI]

hal-00135292,version1-7Mar2007 Photovoltaic Probe of Cavity Polaritons in a Quantum Cascade and a photonic mode of a planar microcavity has been detected by angle-resolved photovoltaic measure- ments polaritons in angle-resolved photovoltaic measurements, performed on a quan- tum cascade (QC) structure

Boyer, Edmond

319

Does removal of an alien predator from small islands in the Baltic Sea induce a trophic cascade?  

E-Print Network [OSTI]

Does removal of an alien predator from small islands in the Baltic Sea induce a trophic cascade known as a trophic cascade. Because alien predators can have a disproportionate impact, compared communities than native predators. We studied the indirect effects of the removal of an alien predator

Oksanen, Lauri

320

Abstract-The ability of cascaded H-bridge multilevel inverter drives (MLID) to operate under faulty condition including AI-  

E-Print Network [OSTI]

for electric drive application have been discussed in [1]. The cascaded MLID is a general fit for large automotive all-electric drives because of the high VA rating possible and because it uses several dc voltage-phase cascaded multilevel inverter drive for an electric vehicle is illustrated in Fig. 1. The series of H

Tolbert, Leon M.

Note: This page contains sample records for the topic "region cascades gea" 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

1058 IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS, VOL. 49, NO. 5, OCTOBER 2002 Charge Balance Control Schemes for Cascade  

E-Print Network [OSTI]

electric vehicle (HEV) motor drives. Multilevel converters: 1) can gen- erate near-sinusoidal voltages system. The cascade inverter is a natural fit for large automotive hybrid electric drives because it uses--Cascade inverter, hybrid electric vehicle, motor drive, multilevel converter, multilevel inverter. I. INTRODUCTION

Tolbert, Leon M.

322

Masting and trophic cascades: interplay between rowan trees, apple fruit moth, and their parasitoid in southern Norway  

E-Print Network [OSTI]

Masting and trophic cascades: interplay between rowan trees, apple fruit moth, and their parasitoid. 2004. Masting and trophic cascades: interplay between rowan trees, apple fruit moth of the dominant seed predator and its parasitoid. The apple fruit moth, Argyresthia conjugella Zeller, is a pre

323

Performance analysis of the cascade impactor, the federal reference method PM 2.5 sampler, and the improve PM 2.5 sampler  

E-Print Network [OSTI]

documented problems with the cascade impactor and suspicions over its accuracy. In this thesis research, the collected PM fractions from the cascade impactor will be subjected to analysis by the Coulter Counter Multisizer to verify inaccuracies. The new FRM...

Buch, Usha-Maria

2012-06-07T23:59:59.000Z

324

A calculation of the number of muons at sea-level in a photon-electron cascade initiated by a primary photon of energy 1014eV  

Science Journals Connector (OSTI)

The muon component in a photon-electron cascade initiated...14...eV has been estimated for sea-level in the longitudinal development of the electromagnetic cascade. Two distinct possible processes of muon product...

N. Mishra

1966-01-11T23:59:59.000Z

325

Region 9: Pacific Rim Region, Regional Sustainability Plan  

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

REGION 9: PACIFIC RIM REGION REGION 9: PACIFIC RIM REGION Regional Sustainability Plan Presented by Ruth Cox Region 9 Regional Administrator Federal Utility Partnership Working Group (FUPWG) May 22 nd , 2013 REGION 9 INFORMATION MANAGE Federal space  36 million RSF in Region Nine * 173 owned buildings, 955 leased buildings * 100,000 Federal workers housed DESIGN & CONSTRUCT new Federal buildings $1.4 billion in FY12 capital construction projects $318 million in FY13 - Los Angeles Courthouse project PROVIDE PROCUREMENT LEADERSHIP across the Federal government  $1.24 billion in total GSA Schedule sales in FY12  $468 million to small businesses  34,000 fleet vehicles, 53% of which are Alternative Fuel Vehicles Pacific Rim Profile - CA, AZ, NV, HI

326

Optimization of control of long-term operating conditions of hydroelectric stations with special reference to the Angara-Enisei cascade of hydroelectric stations  

Science Journals Connector (OSTI)

1. To increase the effectiveness of using water and energy resources by cascades of reservoirs, it is necessary ...

A. Yu. Aleksandrovskii; G. F. Chernenko; N. K. Litvin

1989-08-01T23:59:59.000Z

327

The Role of Damage Cascade in the Nanocrystallization of Metallic Glass  

E-Print Network [OSTI]

was performed, enabling a link between the damage cascade event to the subsequent heat transfer. Modeling results indicate that for 1 MeV Ni ion irradiation in Ni52.5Nb10Zr15Ti15Pt7.5, the heat transfer rate is too large for direct crystallization. Although...

Myers, Michael T.

2011-08-08T23:59:59.000Z

328

Rescuing ecosystems from extinction cascades through compensatory perturbations Sagar Sahasrabudhe & Adilson E. Motter  

E-Print Network [OSTI]

corresponds to the sole zero-population species at a stable target state (in addition to the primary removal state in addition to the one introduced by the primary removal. This forced removal drives the system. The statistics are for all cascades mitigated by a species removal in Fig. 2b of the paper. The rescue states

Shahriar, Selim

329

Global Optimization Methods for the Aerodynamic Shape Design of Transonic Cascades  

E-Print Network [OSTI]

Global Optimization Methods for the Aerodynamic Shape Design of Transonic Cascades T. Mengistu algorithms, namely Genetic Algorithm (GA) and Simulated Annealing (SA), have been applied to the aerodynamic reduction in total pressure loss by eliminating the passage shock. 1. INTRODUCTION Aerodynamic optimization

Neumaier, Arnold

330

To appear in The Electricity Journal, Dec. 2003 Cascading Failures: Survival vs. Prevention  

E-Print Network [OSTI]

1 To appear in The Electricity Journal, Dec. 2003 Cascading Failures: Survival vs. Prevention systems, more data collection, more data processing, load management, and more programs to promote, though the really big ones are not quite as infrequent as one might first expect. The North American

331

Analytic target cascading in simulation-based building design R. Choudharya,*, A. Malkawib  

E-Print Network [OSTI]

of an office building by posing the problem as a constrained non- linear optimization problem. Gero et al. [9] included energy efficiency in the context of other performance criteria and proposed a design optimizationAnalytic target cascading in simulation-based building design R. Choudharya,*, A. Malkawib , P

Papalambros, Panos

332

Assessing Water Deprivation at the Sub-river Basin Scale in LCA Integrating Downstream Cascade Effects  

Science Journals Connector (OSTI)

Assessing Water Deprivation at the Sub-river Basin Scale in LCA Integrating Downstream Cascade Effects ... Although these indicators represent a great step forward in the assessment of water-use-related impacts in LCA, significant challenges still remain in improving their accuracy and relevance. ...

Philippe Loubet; Philippe Roux; Montserrat Nez; Gilles Belaud; Vronique Bellon-Maurel

2013-11-20T23:59:59.000Z

333

Spectral analysis for cascade-emission-based quantum communication in atomic ensembles  

E-Print Network [OSTI]

The ladder configuration of atomic levels provides a source for telecom photons (signal) from the upper atomic transition. \\ For rubidium and cesium atoms, the signal field has the range around 1.3-1.5 $\\mu$m that can be coupled to an optical fiber and transmitted to a remote location. \\ Cascade emission may result in pairs of photons, the signal entangled with the subsequently emitted infrared photon (idler) from the lower atomic transition.\\ This correlated two-photon source is potentially useful in the (Duan-Lukin-Cirac-Zoller) DLCZ protocol for the quantum repeater.\\ We implement the cascade emission to construct a modified DLCZ quantum repeater and investigate the role of time-frequency entanglement in the protocol.\\ The dependence of protocol on photon-number resolving and non-resolving detectors is also studied.\\ We find that frequency entanglement deteriorates the performance but the harmful effect can be diminished by using shorter pump pulses to generate the cascade emission.\\ An optimal cascade-emission-based DLCZ scheme is realized by applying a pure two-photon source in addition to using detectors of perfect quantum efficiency.

H. H. Jen

2014-03-11T23:59:59.000Z

334

Wave Turbulence in Superfluid 4 Energy Cascades, Rogue Waves & Kinetic Phenomena  

E-Print Network [OSTI]

Outline Wave Turbulence in Superfluid 4 He: Energy Cascades, Rogue Waves & Kinetic Phenomena Conference, Chernogolovka, 3 August 2009 McClintock Efimov Ganshin Kolmakov Mezhov-Deglin Wave Turbulence in Superfluid 4 He #12;Outline Outline 1 Introduction Motivation 2 Modelling wave turbulence Need for models

Fominov, Yakov

335

A Novel Cross-Flow Cascade Packed Column Design and Simulation  

Science Journals Connector (OSTI)

A Novel Cross-Flow Cascade Packed Column Design and Simulation ... Thus the abundant area for gas flow will decrease gas-phase pressure drop, and it can allow operation at gas velocities above the flooding points of countercurrent packed columns. ...

Fengrong Chen; Rongqi Zhou; Zhanting Duan; Yumei Liu

1999-07-03T23:59:59.000Z

336

INVESTIGATION OF PERIODIC BOUNDARY CONDITIONS IN MULTIPASSAGE CASCADE FLOWS USING OVERSET GRIDS  

E-Print Network [OSTI]

. Computational results are presented for two and four passage, subsonic and tran­ sonic flows through a turbine and a compressor cascade. The overset grid solutions over the multi­passage periodic domains agree well in Refers to inflow exit Refers to outflow a Acoustic speed A Max. amplitude of the plunging motion c Blade

Tuncer, Ismail H.

337

Molecular Dynamics Simulation of Cascade-Induced Ballistic Helium Resolutioning from Bubbles in Iron  

SciTech Connect (OSTI)

Molecular dynamics simulations have been used to assess the ability of atomic displacement cascades to eject helium from small bubbles in iron. This study of the ballistic resolutioning mechanism employed a recently-developed Fe-He interatomic potential in concert with an iron potential developed by Ackland and co-workers. The primary variables examined were: irradiation temperature (100 and 600K), cascade energy (5 and 20 keV), bubble radius (0.5 and 1.0 nm), and He-to-vacancy ratio in the bubble (0.25, 0.5 and 1.0). Systematic trends were observed for each of these variables. For example, ballistic resolutioning leads to a greater number of helium atoms being displaced from larger bubbles and from bubbles that have a higher He/vacancy ratio (bubble pressure). He resolutioning was reduced at 600K relative to 100K, and for 20 keV cascades relative to 5 keV cascades. Overall, the results indicate a modest level of He removal by ballistic resolutioning. The results can be used to provide guidance in selection of a resolution parameter that can be employed in cluster dynamics models to predict the bubble size distribution that evolves under irradiation.

Stoller, Roger E [ORNL] [ORNL

2013-01-01T23:59:59.000Z

338

Abstract-A hybrid cascaded multilevel inverter application for renewable energy resources including a reconfiguration  

E-Print Network [OSTI]

be achieved by using the microgrid concept as discussed in [2]. Data center or telecommunication buildings an alternative topology of hybrid cascaded multilevel inverter applied to a low voltage dc microgrid, micro-turbine, wind turbine and fuel cell put forward many promising applications with high efficiency

Tolbert, Leon M.

339

A Hybrid Energy System Using Cascaded H-bridge Converter , Zhong Du2  

E-Print Network [OSTI]

schemes were developed to extract maximum wind power and charge/discharge the battery with fast dynamics proposes a hybrid energy system to integrate the variable-speed wind turbine, fuel cell, and battery using a cascaded H-bridge converter. One of the advantages of this topology is that it still can obtain

Tolbert, Leon M.

340

Method of making cascaded die mountings with springs-loaded contact-bond options  

DOE Patents [OSTI]

A cascaded die mounting device and method using spring contacts for die attachment, with or without metallic bonds between the contacts and the dies, is disclosed. One embodiment is for the direct refrigerant cooling of an inverter/converter carrying higher power levels than most of the low power circuits previously taught, and does not require using a heat sink.

Hsu, John S. (Oak Ridge, TN); Adams, Donald J. (Knoxville, TN); Su, Gui-Jia (Knoxville, TN); Marlino, Laura D. (Oak Ridge, TN); Ayers, Curtis W. (Kingston, TN); Coomer, Chester (Knoxville, TN)

2007-06-19T23:59:59.000Z

Note: This page contains sample records for the topic "region cascades gea" 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

Quantum Cascade Lasers Tuned by Amorphous As2S3 Claddings Daniel L. Recht1  

E-Print Network [OSTI]

(roughly 5-20 µm) makes them a natural choice for trace gas sensing. The spectroscopic fingerprints of many). The output range of QCLs provides a natural solution to this problem. Trace gas sensing has thus beenQuantum Cascade Lasers Tuned by Amorphous As2S3 Claddings Daniel L. Recht1 , Zhijun Liu1

Arnold, Craig B.

342

Cascading uncertainty in climate change models and its implications for policy  

E-Print Network [OSTI]

Commentary Cascading uncertainty in climate change models and its implications for policy MARK, there are intrinsic problems with modelling natural systems (Cartwright 1983). This is because it is impossible). The original IPCC reports used simplistic assumption of greenhouse gas emissions over the next 100 years. From

Jones, Peter JS

343

Evolving Cascades of Voting Feature Detectors for Vehicle Detection in Satellite Imagery  

E-Print Network [OSTI]

Evolving Cascades of Voting Feature Detectors for Vehicle Detection in Satellite Imagery Krzysztof method for detection of vehicles in satellite imagery which involves a large number of simple elementary features and multiple detectors trained by genetic programming. The complete detection system is com- posed

Fernandez, Thomas

344

Linking Marketing and Engineering Product Design Decisions via Analytical Target Cascading  

E-Print Network [OSTI]

Linking Marketing and Engineering Product Design Decisions via Analytical Target Cascading? Jeremy to consumers and are feasible to produce. The resulting marketing and engineering design goals are driven decisions when the two problems are interrelated. A meth- od new to the marketing community, analytical

Papalambros, Panos

345

Terahertz Time Domain Spectroscopy of Phonon-Depopulation Based Quantum Cascade Lasers  

SciTech Connect (OSTI)

A 3.1 THz phonon depopulation-based quantum-cascade-laser is investigated using terahertz time domain spectroscopy. A gain of 25 cm{sup -1} and absorption features due to the lower laser level being populated from a parasitic electronic channel are highlighted.

Rungsawang, R.; Dhillon, S. S.; Jukam, N.; Oustinov, D.; Madeo, J.; Tignon, J. [Laboratoire Pierre Aigrain, Ecole Normale Superieure, UMR8551 CNRS, UPMC Univ. Paris 6, F-75005 Paris (France); Colombelli, R. [Institut d'Electronique Fondamentale, Universite Paris Sud, UMR8622 CNRS, 91405 Orsay (France); Dean, P.; Salih, M.; Khanna, S. P.; Linfield, E.; Davies, A. G. [School of Electronic and Electrical Engineering, University of Leeds, Leeds, LS2 9JT (United Kingdom)

2011-12-23T23:59:59.000Z

346

A tunable single-mode double-ring quantum-cascade laser  

Science Journals Connector (OSTI)

The design, fabrication and characterization of a monolithic double-ring quantum- cascade laser (DRQCL) are described. At a wavelength of 4.6m, we demonstrate tunable, single-mode operation of a DRQCL and use it as a source for spectroscopy of CO gas.

D Dhirhe; T J Slight; C C Nshii; C N Ironside

2012-01-01T23:59:59.000Z

347

Sensitive detection of methane and nitrous oxide isotopomers using a continuous wave quantum cascade laser  

Science Journals Connector (OSTI)

A continuous wave quantum cascade laser (QCL), operating near 8.1 ?m...4) and nitrous oxide (N2O) stable isotopes. Several rotational transitions of 14N2 16O, 15N14N16O, 14N2 18O,

G. Gagliardi; F. Tamassia; P. De Natale

2002-06-01T23:59:59.000Z

348

Al composition dependency of interface phonon in the wurtzite quantum cascade laser  

Science Journals Connector (OSTI)

The interface (IF) phonons of the wurtzite quantum cascade lasers (QCL) are investigated using the transfer-...0.2Ga0.8N/GaN and Al0.15Ga0.85N/GaN QCLs, and two IF modes can be changed into other modes if their w...

Gui-chu Chen ???; Guang-han Fan ???

2010-05-01T23:59:59.000Z

349

Two-cascade acousto-optic dispersive delay line for ultrashort laser pulses  

SciTech Connect (OSTI)

An optical dispersive delay line for controlling the spectral composition and phase of ultrashort laser pulses is considered. To control independently the spectral amplitude and spectral phase of pulses, it is proposed to use the cascade arrangement of two acousto-optic cells with different control signals. (letters)

Molchanov, V Ya; Chizhikov, S I; Yushkov, K B [National University of Science and Technology 'MISIS', Moscow (Russian Federation)

2011-08-31T23:59:59.000Z

350

Intracavity Sensing via Compliance Voltage in an External Cavity Quantum Cascade Laser  

SciTech Connect (OSTI)

We demonstrate a technique for gas phase spectroscopy and sensing by detecting changes in compliance voltage of an external cavity quantum cascade laser due to intracavity absorption. The technique is characterized and used to measure the absorption spectrum of water vapor and Freon-134a.

Phillips, Mark C.; Taubman, Matthew S.

2012-07-01T23:59:59.000Z

351

Arrays and Cascades of Fluorescent Liquid-Liquid Waveguides: Broadband Light Sources for  

E-Print Network [OSTI]

Arrays and Cascades of Fluorescent Liquid-Liquid Waveguides: Broadband Light Sources) microchannel waveguides with liquid cores containing fluorescent dyes, excited by incident light from an external halogen bulb. Simultaneous use of multiple fluorophores in a common solution, in a single L2 light

Prentiss, Mara

352

Thermionic/AMTEC cascade converter concept for high-efficiency space power  

SciTech Connect (OSTI)

This paper presents trade studies that address the use of the thermionic/AMTEC cell--a cascaded, high-efficiency, static power conversion concept that appears well-suited to space power applications. Both the thermionic and AMTEC power conversion approaches have been shown to be promising candidates for space power. Thermionics offers system compactness via modest efficiency at high heat rejection temperatures, and AMTEC offers high efficiency at modest heat rejection temperature. From a thermal viewpoint the two are ideally suited for cascaded power conversion: thermionic heat rejection and AMTEC heat source temperatures are essentially the same. In addition to realizing conversion efficiencies potentially as high as 35--40%, such a cascade offers the following perceived benefits: survivability; simplicity; technology readiness; and technology growth. Mechanical approaches and thermal/electric matching criteria for integrating thermionics and AMTEC into a single conversion device are described. Focusing primarily on solar thermal space power applications, parametric trends are presented to show the performance and cost potential that should be achievable with present-day technology in cascaded thermionic/AMTEC systems.

Hagan, T.H. van; Smith, J.N. Jr. [General Atomics, San Diego, CA (United States); Schuller, M. [PL/VTP, Kirtland AFB, NM (United States)

1996-12-31T23:59:59.000Z

353

Inverse Kirkendall mixing in collision cascades K. Nordlund* and R. S. Averback  

E-Print Network [OSTI]

in reactor mate- rials, and processing of materials by high strain conditions. Theoretical approaches as Co, but has a much smaller heat of mixing with Cu, comparison of cascade mixing in Ni effect,7 in which a vacancy flux drives a net solute flux in the opposite direction. Classical molecular

Nordlund, Kai

354

Modeling, Optimization, and Experimentation with a Two Stage Mixed Gas Cascaded Joule Thomson Cryoprobe  

E-Print Network [OSTI]

Modeling, Optimization, and Experimentation with a Two Stage Mixed Gas Cascaded Joule Thomson-stage Mixed Gas Joule Thomson (MGJT) cycle is capable of providing compact cooling for cryoprobes". A computational model of a commercially available two stage MGJT cryoprobe donated by American Medical Systems

Wisconsin at Madison, University of

355

State & Regional Resources  

Broader source: Energy.gov [DOE]

The Bioenergy Technologies Office partners with the National Biomass State and Regional Partnerships' five regional organizations that provide leadership in their regions with regard to policies...

356

Regional Summary Pacific Region Management Context  

E-Print Network [OSTI]

, for the Eastern Pacific Ocean, and the Western and Central Pacific Fishery Commission, for the Western PacificRegional Summary Pacific Region Management Context The Pacific Region includes California, Oregon, and Washington. Federal fisheries in this region are managed by the Pacific Fishery Management Council (PFMC

357

The nitrogen cascade from agricultural soils to the sea: modelling nitrogen transfers at regional watershed and global scales  

Science Journals Connector (OSTI)

...towards collection of wastewater in centralized sewers...Taking into account recycling of sewage to agriculture...rural areas) and wastewater treatment (in urban...3480 292 130 1030 wastewater treatment or recycling 735 2430 118 40 530...

2013-01-01T23:59:59.000Z

358

Influence of confined phonon modes on the thermal behavior of AlAs/GaAs quantum cascade structures  

Science Journals Connector (OSTI)

The thermal behavior of AlAs/GaAs quantum cascade structures is used to demonstrate the existence of confined and interface optical-phonon modes. The high conduction-band offset of this material system greatly improves the confinement of the electronic states and allows the realization of electroluminescence structures, where the optical power as a function of the temperature solely depends on the change of the upper-state lifetime induced by the longitudinal-optical-phonon population. We observed that the latter is proportional to the Bose-Einstein factor, with an appropriate phonon mode energy, which does not simply correspond to that of the GaAs bulk phonon (36-meV energy). In particular we show that the agreement between theory and experiment can be substantially improved when the confined and interface modes are taken into account in our calculation. Our results are corroborated by the threshold temperature dependence of lasers, with an active region based on similar structures.

C. Becker; C. Sirtori; H. Page; A. Robertson; V. Ortiz; X. Marcadet

2002-01-30T23:59:59.000Z

359

Thermodynamic analysis of a transcritical CO2/propylene (R744R1270) cascade system for cooling and heating applications  

Science Journals Connector (OSTI)

Abstract In this paper natural refrigerant propylene (R1270) has been proposed for transcritical cascade refrigeration system and analyzed. Propylene is used in the low temperature (LT) cycle and carbon dioxide is used in the high temperature (HT) cycle of the cascade transcritical refrigeration system. The proposed transcritical cascade cycle can be used for simultaneous cooling and heating applications. Thermal performance of the cascade cycle is evaluated for different combinations of design and operating variables and optimum performance parameters such as Topt, \\{COPmax\\} and mass flow of propylene and CO2 have been predicted. Design parameters include the evaporator temperature of LT cycle (TE), gas cooler outlet temperature (TC) and cascade heat exchanger temperature difference (DT). The results of the analysis show better thermal performance of CO2propylene transcritical cycle than subcritical cascade cycle and also better than N2OCO2 transcritical cycle. A methodology to obtain relevant performance diagrams and regression correlations to serve as a guideline for the design and optimization of transcritical CO2propylene cascade system has been developed.

Alok Manas Dubey; Suresh Kumar; Ghanshyam Das Agrawal

2014-01-01T23:59:59.000Z

360

Above room-temperature operation of InAs/AlGaSb superlattice quantum cascade lasers emitting at 12 {mu}m  

SciTech Connect (OSTI)

The authors report on above-room-temperature operation of InAs/AlGaSb quantum cascade lasers emitting at 12 {mu}m. The laser structures are grown on a n-InAs (100) substrate using solid-source molecular beam epitaxy. An InAs/AlGaSb superlattice is used as an active part and an InAs double plasmon waveguide is used for optical confinement. Results show that increased doping concentration in the injection part of the active region expands the current operation range of the devices, allowing laser operation at and above room temperature. The observed threshold current density is 4.0 kA/cm{sup 2} at 300 K; the maximum operation temperature is 340 K.

Ohtani, K.; Moriyasu, Y.; Ohnishi, H.; Ohno, H. [Laboratory for Nanoelectronics and Semiconductor Spintronics, Research Institute of Electrical Communication, Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai 980-8577 (Japan)

2007-06-25T23:59:59.000Z

Note: This page contains sample records for the topic "region cascades gea" 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

Are there significant hydrothermal resources in the US part of the Cascade Range?  

SciTech Connect (OSTI)

The Cascade Range is a geothermal dichotomy. On the one hand, it is an active volcanic arc above a subducting plate and is demonstrably an area of high heat flow. On the other hand, the distribution of hydrothermal manifestations compared to other volcanic arcs is sparse, and the hydrothermal outflow calculated from stream chemistry is low. Several large estimates of undiscovered geothermal resources in the U.S. part of the Cascade Range prepared in the 1970s and early 1980s were based fundamentally on two models of the upper crust. One model assumed that large, partly molten, intrusive bodies exist in the upper 10 km beneath major volcanic centers and serve as the thermal engines driving overlying hydrothermal systems. The other model interpreted the coincident heat-flow and gravity gradients west of the Cascade crest in central Oregon to indicate a partly molten heat source at 10 {+-} 2 km depth extending {approx}30 km west from the axis of the range. Investigations of the past ten years have called both models into question. Large long-lived high-temperature hydrothermal systems at depths <3 km in the U.S. part of the Cascade Range appear to be restricted to silicic domefields at the Lassen volcanic center, Medicine Lake volcano, Newberry volcano, and possibly the Three Sisters. Federal land-use restrictions further reduce this list to Medicine Lake and Newberry. Dominantly andesitic stratocones appear to support only small transitory hydrothermal systems related to small intrusive bodies along the volcanic conduits. The only young caldera, at Crater Lake, supports only low- to intermediate-temperature hydrothermal systems. Most of the Cascade Range comprises basaltic andesites and has little likelihood for high-level silicic intrusions and virtually no potential for resultant large high-temperature hydrothermal systems. Undiscovered hydrothermal resources of the Cascade Range of the United States are substantially lower than previous estimates. The range does have potential for intermediate-temperature hot dry rock and localized low- to intermediate-temperature hydrothermal systems.

Muffler, L.J. Patrick; Guffanti, Marianne

1995-01-26T23:59:59.000Z

362

Aerodynamic Losses and Heat Transfer in a Blade Cascade with 3-D Endwall Contouring  

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

Aerodynamic Losses and Heat Transfer in a Aerodynamic Losses and Heat Transfer in a Aerodynamic Losses and Heat Transfer in a Aerodynamic Losses and Heat Transfer in a Blade Cascade with 3 Blade Cascade with 3 - - D D Endwall Endwall Contouring Contouring Principal Investigator Principal Investigator Sumanta Acharya, Professor Sumanta Acharya, Professor Louisiana State University, Baton Rouge, Louisiana Louisiana State University, Baton Rouge, Louisiana Collaborators Collaborators Gazi Mahmood, Ph.D., Research Asqociate Gazi Mahmood, Ph.D., Research Asqociate Arun Saha, Ph.D., Research Associate Arun Saha, Ph.D., Research Associate Ross Gustafson, M.S. student Ross Gustafson, M.S. student SCIES Project 02 SCIES Project 02 - - 01 01 - - SR098 SR098 DOE COOPERATIVE AGREEMENT DE DOE COOPERATIVE AGREEMENT DE - - FC26 FC26 - - 02NT41431 02NT41431 Tom J. George, Program Manager, DOE/NETL

363

Cascading metallic gratings for broadband absorption enhancement in ultrathin plasmonic solar cells  

SciTech Connect (OSTI)

The incorporation of plasmonic nanostructures in the thin-film solar cells (TFSCs) is a promising route to harvest light into the nanoscale active layer. However, the light trapping scheme based on the plasmonic effects intrinsically presents narrow-band resonant enhancement of light absorption. Here we demonstrate that by cascading metal nanogratings with different sizes atop the TFSCs, broadband absorption enhancement can be realized by simultaneously exciting multiple localized surface plasmon resonances and inducing strong coupling between the plasmonic modes and photonic modes. As a proof of concept, we demonstrate of 66.5% in the photocurrent in an ultrathin amorphous silicon TFSC with two-dimensional cascaded gratings over the reference cell without gratings.

Wen, Long; Sun, Fuhe [Key Laboratory of Nanodevices and Applications-CAS and Collaborative Innovation Center of Suzhou Nano Science and Technology, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences (CAS), Suzhou 215123 (China); Chen, Qin, E-mail: qchen2012@sinano.ac.cn [Key Laboratory of Nanodevices and Applications-CAS and Collaborative Innovation Center of Suzhou Nano Science and Technology, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences (CAS), Suzhou 215123 (China); Peking University Shenzhen SOC Key Laboratory, PKU-HKUST Shenzhen-Hong Kong Institute, Hi-Tech Industrial Park South, Shenzhen 518057 (China)

2014-04-14T23:59:59.000Z

364

CONTROL OF POLLUTANT EMISSIONS IN NATURAL GAS DIFFUSION FLAMES BY USING CASCADE BURNERS  

SciTech Connect (OSTI)

The advanced CFDRC software package was installed on a SUN-SPARC dual processor workstation (UTPA funded). The literature pertinent to the project was collected. The physical model was set and all parameters and variables were identified. Based on the physical model, the geometric modeling and grid generation processes were performed using the CFD-GEOM (Interactive Geometric Modeling and Grid Generation software). A total number of 11160 cells (248 x 45) were generated. The venturis in the cascade were modeled as two-dimensional axisymmetric convergent nozzles around the jet. With the cascade being added to the jet, the geometric complexity of the problem increased; which required multi-domain structured grid systems to be connected and matched on the boundaries. The natural gas/propane jet diffusion flame is being numerically analyzed. The numerical computations are being conducted using the CFDRC-ACE+ (advanced computational environment) software package. The results are expected soon.

Ala Qubbaj

2001-03-30T23:59:59.000Z

365

Critical points and transitions in an electric power transmission model for cascading failure blackouts  

Science Journals Connector (OSTI)

Cascading failures in large-scale electric power transmission systems are an important cause of blackouts. Analysis of North American blackout data has revealed power law (algebraic) tails in the blackout size probability distribution which suggests a dynamical origin. With this observation as motivation we examine cascading failure in a simplified transmission system model as load power demand is increased. The model represents generators loads the transmission line network and the operating limits on these components. Two types of critical points are identified and are characterized by transmission line flow limits and generator capability limits respectively. Results are obtained for tree networks of a regular form and a more realistic 118-node network. It is found that operation near critical points can produce power law tails in the blackout size probability distribution similar to those observed. The complex nature of the solution space due to the interaction of the two critical points is examined.

B. A. Carreras; V. E. Lynch; I. Dobson; D. E. Newman

2002-01-01T23:59:59.000Z

366

Laser frequency stabilization to excited state transitions using electromagnetically induced transparency in a cascade system  

SciTech Connect (OSTI)

We demonstrate laser frequency stabilization to excited state transitions using cascade electromagnetically induced transparency. Using a room temperature Rb vapor cell as a reference, we stabilize a first diode laser to the D{sub 2} transition and a second laser to a transition from the intermediate 5P{sub 3/2} state to a highly excited state with principal quantum number n=19-70. A combined laser linewidth of 280{+-}50 kHz over a 100 {mu}s time period is achieved. This method may be applied generally to any cascade system and allows laser stabilization to an atomic reference in the absence of a direct absorption signal.

Abel, R. P.; Mohapatra, A. K.; Bason, M. G.; Pritchard, J. D.; Weatherill, K. J.; Raitzsch, U.; Adams, C. S. [Department of Physics, Durham University, Rochester Building, South Road, Durham DH1 3LE (United Kingdom)

2009-02-16T23:59:59.000Z

367

A high carrier injection terahertz quantum cascade laser based on indirectly pumped scheme  

SciTech Connect (OSTI)

A Terahertz quantum cascade laser with a rather high injection coupling strength based on an indirectly pumped scheme is designed and experimentally implemented. To effectively suppress leakage current, the chosen quantum cascade module of the device is based on a five-well GaAs/Al{sub 0.25}Ga{sub 0.75}As structure. The device lases up to 151?K with a lasing frequency of 2.67 THz. This study shows that the effect of higher energy states in carrier transport and the long-range tunnel coupling between states that belong to non-neighbouring modules have to be considered in quantum design of structures with a narrow injector barrier. Moreover, the effect of interface roughness scattering between the lasing states on threshold current is crucial.

Razavipour, S. G., E-mail: sgrazavi@uwaterloo.ca; Xu, C.; Wasilewski, Z. R.; Ban, D. [Department of Electrical and Computer Engineering, Waterloo Institute for Nanotechnology, University of Waterloo, 200 University Ave. W., Waterloo, Ontario N2L3G1 (Canada); Dupont, E.; Laframboise, S. R. [National Research Council, Blg. M-50, 1200 Montreal Rd., Ottawa, Ontario K1A0R6 (Canada); Chan, C. W. I.; Hu, Q. [Department of Electrical Engineering and Computer Science, Research Laboratory of Electronics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2014-01-27T23:59:59.000Z

368

Collective Lamb shift of superradiant cascade emissions in an atomic ensemble  

E-Print Network [OSTI]

We calculate the collective Lamb shift of the cascade spontaneous emissions from an atomic ensemble driven by two-color classical fields. The correlated pair of photons (signal and idler) is generated by adiabatically driving the system with large-detuned light fields in four-wave-mixing condition. The signal photon from the upper transition of the diamond-type atomic levels is followed by the idler one which can be superradiant due to light-induced dipole-dipole interactions. We demonstrate that the collective Lamb shift of the idler photon is a cumulative effect of interaction energy, and investigate its dependence on a cylindrical geometry. Manipulating the collective frequency of cascade emissions enables frequency qubits that provide alternative robust elements in quantum network.

H. H. Jen

2015-01-21T23:59:59.000Z

369

Spontaneous current-layer fragmentation and cascading reconnection in solar flares: I. Model and analysis  

E-Print Network [OSTI]

Magnetic reconnection is commonly considered as a mechanism of solar (eruptive) flares. A deeper study of this scenario reveals, however, a number of open issues. Among them is the fundamental question, how the magnetic energy is transferred from large, accumulation scales to plasma scales where its actual dissipation takes place. In order to investigate this transfer over a broad range of scales we address this question by means of high-resolution MHD simulation. The simulation results indicate, that the magnetic-energy transfer to small scales is realized via a cascade of consecutive smaller and smaller flux-ropes (plasmoids), in analogy with the vortex-tube cascade in (incompressible) fluid dynamics. Both tearing and (driven) coalescence processes are equally important for the consecutive fragmentation of the magnetic field (and associated current density) to smaller elements. At the later stages a dynamic balance between tearing and coalescence processes reveals a steady (power-law) scaling typical for ca...

Brta, Miroslav; Karlick, Marian; Skla, Jan

2010-01-01T23:59:59.000Z

370

Modeling and controller synthesis for the cascaded H-bridge multilevel active power filter with ADALINE-based identifiers  

Science Journals Connector (OSTI)

This paper presents the averaged state-space modeling and controller synthesis methodology for the cascaded H-bridge multilevel active power filters (CHB-APFs). ... compensation and dc-link stabilization among th...

Yang Han; Lin Xu; Muhammad Mansoor Khan; Chen Chen

2011-06-01T23:59:59.000Z

371

A Comparison on PSO Variants in Calculating HEPWM Switching Angles for a Cascaded H-Bridge Multilevel Inverter  

Science Journals Connector (OSTI)

This paper presents a comparison study on the application of various PSO algorithms in calculating the Pulse Width Modulation (PWM) switching angles of a cascaded H-bridge multilevel inverter. It aims to investig...

Norkharziana Mohd Nayan; Naziha Ahmad Azli

2012-01-01T23:59:59.000Z

372

Linewidth of a quantum-cascade laser assessed from its frequency noise spectrum and impact of the current driver  

Science Journals Connector (OSTI)

We report on the measurement of the frequency noise properties of a 4.6-?m distributed-feedback quantum-cascade laser (QCL) operating in continuous wave near...?1...is used to convert the frequency fluctuations o...

L. Tombez; S. Schilt; J. Di Francesco; T. Fhrer; B. Rein; T. Walther

2012-11-01T23:59:59.000Z

373

Laser Action at High k-Space Values in Anti-Correlated Multi-Wavelength Quantum Cascade Lasers  

Science Journals Connector (OSTI)

A two-wavelength Quantum Cascade laser is reported in which one wavelength lases between subband states high in the k-space. Laser action at the two wavelengths is strongly...

Menzel, Stefan; Franz, Kale J; Wasserman, Daniel; Hoffman, Anthony J; Cockburn, John W; Gmachl, Claire F

374

Study of methods for lowering the lasing frequency of a terahertz quantum-cascade laser based on two quantum wells  

Science Journals Connector (OSTI)

Two mechanisms for achieving lower terahertz-range frequencies in quantum-cascade structures with two quantum wells based on GaAs/AlGaAs compounds are ... mechanism is based on the introduction of composite quantum

D. V. Ushakov; Yu. G. Sadofyev; N. Samal

2012-11-01T23:59:59.000Z

375

A coherent quantum cascade laser operating on a combination of even and odd levels of a three-barrier structure  

Science Journals Connector (OSTI)

For the creation of quantum cascade lasers with coherent (collisionless or ballistic) electron ... a level formed from the levels of adjacent quantum wells with different parity of the electron ... increasing the...

. A. Gelvich; E. I. Golant; A. B. Pashkovski?

2006-03-01T23:59:59.000Z

376

Latitudinal gradients of coniferous tree species, vegetation, and climate in the Sierran-Cascade axis of Northern California  

Science Journals Connector (OSTI)

Latitudinal gradients of tree species composition along the Sierran/Cascade axis in northern California were explored by comparing forests of Lassen Volcanic and Yosemite National Parks, USA. A calibration pro...

Albert J. Parker

1994-12-01T23:59:59.000Z

377

Mode-locked terahertz quantum cascade laser by direct phase synchronization  

SciTech Connect (OSTI)

Mode-locking of a terahertz quantum cascade laser is achieved using multimode injection seeding. Contrary to standard methods that rely on gain modulation, here a fixed phase relationship is directly imprinted to the laser modes. In this work, we demonstrate the generation of 9 ps phase mode-locked pulses around 2.75 THz. A direct measurement of the emitted field phase shows that it results from the phase of the initial injection.

Maussang, K.; Maysonnave, J.; Jukam, N.; Freeman, J. R.; Cavali, P.; Dhillon, S. S.; Tignon, J. [Laboratoire Pierre Aigrain, Ecole Normale Suprieure, CNRS (UMR 8551), Universit P. et M. Curie, Universit D. Diderot, 75005 Paris (France); Khanna, S. P.; Linfield, E. H.; Davies, A. G. [School of Electronic and Electrical Engineering, University of Leeds, Leeds LS9 2JT (United Kingdom); Beere, H. E.; Ritchie, D. A. [University of Cambridge, Cavendish Lab, Cambridge CB3 0HE (United Kingdom)

2013-12-04T23:59:59.000Z

378

Fast Hyperspectral Imaging Using a Mid-Infrared Tunable External Cavity Quantum Cascade Laser  

SciTech Connect (OSTI)

An active hyperspectral imaging system using an external cavity quantum cascade laser and a focal plane array acquiring images at 25 Hz from 985 cm-1 to 1075 cm-1 with a resolution of 0.3 cm 1 is demonstrated. The chemical imaging of gases is demonstrated in both static and dynamic cases. The system was also used to analyze liquid and solid samples.

Phillips, Mark C.; Ho, Nicolas

2008-04-23T23:59:59.000Z

379

External Cavity Quantum Cascade Laser for Quartz Tuning Fork Photoacoustic Spectroscopy of Broad Absorption Features  

SciTech Connect (OSTI)

We demonstrate mid-infrared spectroscopy of large molecules with broad absorption features using a tunable external cavity quantum cascade laser. Absorption spectra for two different Freons are measured over the range 1130-1185 cm-1 with 0.2 cm-1 resolution via laser photoacoustic spectroscopy with quartz tuning forks as acoustic transducers. The measured spectra are in excellent agreement with published reference absorption spectra.

Phillips, Mark C.; Myers, Tanya L.; Wojcik, Michael D.; Cannon, Bret D.

2007-05-01T23:59:59.000Z

380

Quantum cascade lasers: a versatile source for precise measurements in the mid/far-infrared range  

Science Journals Connector (OSTI)

We provide an overview of recent developments of quantum cascade lasers (QCLs), from the mid-infrared (mid-IR) to the far-IR (THz) range, with a special focus on their metrological-grade applications in a number of fields. A special emphasis on the physics of the QCLs allows underlining peculiar effects and device features recently unveiled that pave the way to novel demanding photonics applications.

S Bartalini; M S Vitiello; P De Natale

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "region cascades gea" 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

Enantioselectivity in Organocatalytic Cascade Double Michael Addition Reaction: A Theoretical Study  

Science Journals Connector (OSTI)

(38, 39) To consider the solvent effect on reaction, single-point PCM//B3LYP/6-311++G(d,p) calculations with self-consistent reaction field(40-42) based on polarizable continuum model (PCM)(43, 44) were applied for all gas-phase optimized structures. ... The application of cascade reactions to natural products synthesis represents a particularly demanding task, but the results can be both stunning and instructive. ...

Nan Lu; Lin Meng; Dezhan Chen; Guiqiu Zhang

2011-10-10T23:59:59.000Z

382

Cascade Problems in Some Atomic Lifetime Measurements at a Heavy-Ion Storage Ring  

SciTech Connect (OSTI)

Lifetimes of 3s{sup 2}3p{sup k} ground configuration levels of Al-, Si-, P-, and S-like ions of Be, Co, and Ni have been measured at a heavy-ion storage ring. Some of the observed decay curves show strong evidence of cascade repopulation from specific 3d levels that feature lifetimes in the same multi-millisecond range as the levels of the ground configuration.

Trabert, E; Hoffmann, J; Krantz, C; Wolf, A; Ishikawa, Y; Santana, J

2008-10-09T23:59:59.000Z

383

Separation of Fine Particles from Gases in Wet Flue Gas Desulfurization System Using a Cascade of Double Towers  

Science Journals Connector (OSTI)

Separation of Fine Particles from Gases in Wet Flue Gas Desulfurization System Using a Cascade of Double Towers ... The authors thank the High-Tech Research and Development Program of China (No. 2008AA05Z306), the Natural Science Foundation of Jiangsu Province (No. BK2008283), and the Scientific Research Foundation of Graduate School of Southeast University for their financial support. ... with high performance by cascading packed columns. ...

Jingjing Bao; Linjun Yang; Shijuan Song; Guilong Xiong

2012-02-15T23:59:59.000Z

384

Topological Analysis and Mitigation Strategies for Cascading Failures in Power Grid Networks  

E-Print Network [OSTI]

Recently, there has been a growing concern about the overload status of the power grid networks, and the increasing possibility of cascading failures. Many researchers have studied these networks to provide design guidelines for more robust power grids. Topological analysis is one of the components of system analysis for its robustness. This paper presents a complex systems analysis of power grid networks. First, the cascading effect has been simulated on three well known networks: the IEEE 300 bus test system, the IEEE 118 bus test system, and the WSCC 179 bus equivalent model. To extend the analysis to a larger set of networks, we develop a network generator and generate multiple graphs with characteristics similar to the IEEE test networks but with different topologies. The generated graphs are then compared to the test networks to show the effect of topology in determining their robustness with respect to cascading failures. The generated graphs turn out to be more robust than the test graphs, showing the...

Pahwa, Sakshi; Schulz, Noel

2012-01-01T23:59:59.000Z

385

Fundamental Frequency Switching Control of Seven-Level Hybrid Cascaded H-bridge Multilevel Inverter  

SciTech Connect (OSTI)

This paper presents a cascaded H-bridge multilevel inverter that can be implemented using only a single dc power source and capacitors. Standard cascaded multilevel inverters require n dc sources for 2n + 1 levels. Without requiring transformers, the scheme proposed here allows the use of a single dc power source (e.g., a battery or a fuel cell stack) with the remaining n-1 dc sources being capacitors, which is referred to as hybrid cascaded H-bridge multilevel inverter (HCMLI) in this paper. It is shown that the inverter can simultaneously maintain the dc voltage level of the capacitors and choose a fundamental frequency switching pattern to produce a nearly sinusoidal output. HCMLI using only a single dc source for each phase is promising for high-power motor drive applications as it significantly decreases the number of required dc power supplies, provides high-quality output power due to its high number of output levels, and results in high conversion efficiency and low thermal stress as it uses a fundamental frequency switching scheme. This paper mainly discusses control of seven-level HCMLI with fundamental frequency switching control and how its modulation index range can be extended using triplen harmonic compensation.

Du, Zhong [ORNL; Chiasson, John N [ORNL; Ozpineci, Burak [ORNL; Tolbert, Leon M [ORNL

2009-01-01T23:59:59.000Z

386

Analysis and optimization of cascade Rankine cycle for liquefied natural gas cold energy recovery  

Science Journals Connector (OSTI)

Abstract This study proposes a new concept called the cascade Rankine cycle, which recovers LNG (liquefied natural gas) cold energy for power generation, optimizes the cycle by investigating the effects of key parameters on its performance, and compares its thermal efficiency, exergy efficiency and economic evaluation to those of the conventional alternatives. The cascade Rankine cycle consists of multiple stages of the organic Rankine cycle in a layered structure in which the first stage encompasses the second one that, in turn, encompasses the next. Due to its layered configuration, optimization of the cycle is straightforward and involves sequentially optimizing the individual stages. Optimization of the subsequent stages, however, required process simulation considering the equipment efficiency and the thermodynamic properties of the working fluid. Process simulation indicated that the indicators such as net power output, thermal efficiency, and exergy efficiency generally increase as the number of stages increases. These indicators were, however, significantly affected by the thermodynamic properties of the working fluids. The proposed cycles demonstrated significantly better performance in these indicators than the conventional cycles. The three-stage cascade Rankine cycle with propane as the working fluid exhibited the highest net power output, thermal efficiency and exergy efficiency within the set.

In-Hwan Choi; Sangick Lee; Yutaek Seo; Daejun Chang

2013-01-01T23:59:59.000Z

387

FERMI @ Elettra -- A Seeded Harmonic Cascade FEL for EUV and SoftX-rays  

SciTech Connect (OSTI)

We describe the machine layout and major performance parameters for the FERMI FEL project funded for construction at Sincrotrone Trieste, Italy, within the next five years. The project will be the first user facility based on seeded harmonic cascade FELs, providing controlled, high peak-power pulses. With a high-brightness rf photocathode gun, and using the existing 1.2 GeV S-band linac, the facility will provide tunable output over a range from {approx}100 nm to {approx}10nm, with pulse duration from 40 fs to {approx} 1 ps, peak power GW, and with fully variable output polarization. Initially, two FEL cascades are planned; a single-stage harmonic generation to operate >40 nm, and a two stage cascade operating from {approx}40 nm to {approx}10 nm or shorter wavelength. The output is spatially and temporally coherent, with peak power in the GW range. Lasers provide modulation to the electron beam, as well as driving the photocathode and other systems, and the facility will integrate laser systems with the accelerator infrastructure, including a state-of-the-art optical timing system providing synchronization of rf signals, lasers, and x-ray pulses. Major systems and overall facility layout are described, and key performance parameters summarized.

Bocchetta, C.; Bulfone, D.; Craievich, P.; Danailov, M.B.; D'Auria,G.; DeNinno, G.; Di Mitri, S.; Diviacco, B.; Ferianis, M.; Gomezel, A.; Iazzourene, F.; Karantzoulis, E.; Parmigiani, F.; Penco, G.; Trovo, M.; Corlett, J.; Fawley, W.; Lidia, S.; Penn, G.; Ratti, A.; Staples, J.; Wilcox, R.; Zholents, A.; Graves, W.; Ilday, F.O.; Kaertner,F.; Wang, D.; Zwart, T.; Cornacchia, M.; Emma, P.; Huang, Z.; Wu, J.

2005-09-01T23:59:59.000Z

388

FERMI@Elettra: A Seeded Harmonic Cascade FEL for EUV and Soft X-Rays  

SciTech Connect (OSTI)

We describe the machine layout and major performance parameters for the FERMI FEL project funded for construction at Sincrotrone Trieste, Italy, within the next five years. The project will be the first user facility based on seeded harmonic cascade FEL's, providing controlled, high peak-power pulses. With a high-brightness rf photocathode gun, and using the existing 1.2 GeV S-band linac, the facility will provide tunable output over a range from {approx}100 nm to {approx}10 nm, with pulse duration from 40 fs to {approx} 1ps, peak power {approx}GW, and with fully variable output polarization. Initially, two FEL cascades are planned; a single-stage harmonic generation to operate > 40 nm, and a two-stage cascade operating from {approx}40 nm to {approx}10 nm or shorter wavelength. The output is spatially and temporally coherent, with peak power in the GW range. Lasers provide modulation to the electron beam, as well as driving the photocathode and other systems, and the facility will integrate laser systems with the accelerator infrastructure, including a state-of-the-art optical timing system providing synchronization of rf signals, lasers, and x-ray pulses. Major systems and overall facility layout are described, and key performance parameters summarized.

Bocchetta, C.J.; Bulfone, D.; Craievich, P.; Danailov, M.B.; D'Auria, G.; De Ninno, G.; Di Mitri, S.; Diviacco, B.; Ferianis, M.; Gomezel, A.; Iazzourene, F.; Karantzoulis, E.; Parmigiani, F.; Penco, G.; Trovo, M.; /Sincrotrone Trieste; Corlett, J.; Fawley, W.; Lidia, S.; Penn, G.; Ratti, A.; Staples, J.; /LBL, Berkeley /MIT /SLAC

2005-12-14T23:59:59.000Z

389

Kinetic cascade beyond magnetohydrodynamics of solar wind turbulence in two-dimensional hybrid simulations  

Science Journals Connector (OSTI)

The nature of solar windturbulence in the dissipation range at scales much smaller than the large magnetohydrodynamic (MHD) scales remains under debate. Here a two-dimensional model based on the hybrid code abbreviated as A.I.K.E.F. is presented which treats massive ions as particles obeying the kinetic Vlasov equation and massless electrons as a neutralizing fluid. Up to a certain wavenumber in the MHD regime the numerical system is initialized by assuming a superposition of isotropic Alfvn waves with amplitudes that follow the empirically confirmed spectral law of Kolmogorov. Then turbulence develops and energy cascades into the dispersive spectral range where also dissipative effects occur. Under typical solar wind conditions weak turbulence develops as a superposition of normal modes in the kinetic regime. Spectral analysis in the direction parallel to the background magnetic field reveals a cascade of left-handed Alfvn/ion-cyclotron waves up to wave vectors where their resonant absorption sets in as well as a continuing cascade of right-handed fast-mode and whistler waves. Perpendicular to the background field a broad turbulent spectrum is found to be built up of fluctuations having a strong compressive component. Ion-Bernstein waves seem to be possible normal modes in this propagation direction for lower driving amplitudes. Also signatures of short-scale pressure-balanced structures (very oblique slow-mode waves) are found.

D. Verscharen; E. Marsch; U. Motschmann; J. Mller

2012-01-01T23:59:59.000Z

390

Boosting searches for natural supersymmetry with R-parity violation via gluino cascades  

Science Journals Connector (OSTI)

In the presence of even minuscule baryonic R-parity violation (RPV), the stop can be the lightest superpartner and evade LHC searches because it decays into two jets. In order to cover this interesting possibility, we here consider new searches for RPV stops produced in gluino cascades. While typical searches for gluinos decaying to stops rely on same-sign dileptons, the RPV cascades usually have fewer hard leptons, less excess missing energy, and more jets than R-parity conserving cascades. If the gluino is a Dirac fermion, same-sign dilepton signals are also often highly depleted. We therefore explore search strategies that use single-lepton channels, and combat backgrounds using HT, jet counting, and more detailed multijet kinematics or jet substructure. We demonstrate that the stop mass peaks can be fully reconstructed over a broad range of spectra, even given the very high jet multiplicities. This would not only serve as a double-discovery opportunity, but would also be a spectacular confirmation that the elusive top partner has been hiding in multijets.

Zhenyu Han; Andrey Katz; Minho Son; Brock Tweedie

2013-04-02T23:59:59.000Z

391

Effects of temporal correlations on cascades: Threshold models on temporal networks  

Science Journals Connector (OSTI)

A person's decision to adopt an idea or product is often driven by the decisions of peers, mediated through a network of social ties. A common way of modeling adoption dynamics is to use threshold models, where a node may become an adopter given a high enough rate of contacts with adopted neighbors. We study the dynamics of threshold models that take both the network topology and the timings of contacts into account, using empirical contact sequences as substrates. The models are designed such that adoption is driven by the number of contacts with different adopted neighbors within a chosen time. We find that while some networks support cascades leading to network-level adoption, some do not: the propagation of adoption depends on several factors from the frequency of contacts to burstiness and timing correlations of contact sequences. More specifically, burstiness is seen to suppress cascade sizes when compared to randomized contact timings, while timing correlations between contacts on adjacent links facilitate cascades.

Ville-Pekka Backlund; Jari Saramki; Raj Kumar Pan

2014-06-26T23:59:59.000Z

392

Mt St Helens Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

Mt St Helens Geothermal Area Mt St Helens Geothermal Area (Redirected from Mt St Helens Area) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermal Resource Area: Mt St Helens Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory and Environmental Issues 4 Exploration History 5 Well Field Description 6 Geology of the Area 7 Geofluid Geochemistry 8 NEPA-Related Analyses (0) 9 Exploration Activities (8) 10 References Area Overview Geothermal Area Profile Location: Washington Exploration Region: Cascades GEA Development Phase: 2008 USGS Resource Estimate Mean Reservoir Temp: Estimated Reservoir Volume: Mean Capacity: Click "Edit With Form" above to add content History and Infrastructure Operating Power Plants: 0 No geothermal plants listed. Add a new Operating Power Plant

393

Glass Buttes Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

Glass Buttes Geothermal Area Glass Buttes Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermal Resource Area: Glass Buttes Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory and Environmental Issues 4 Exploration History 5 Well Field Description 6 Geology of the Area 7 Geofluid Geochemistry 8 NEPA-Related Analyses (1) 9 Exploration Activities (14) 10 References Area Overview Geothermal Area Profile Location: Oregon Exploration Region: Cascades GEA Development Phase: 2008 USGS Resource Estimate Mean Reservoir Temp: Estimated Reservoir Volume: Mean Capacity: Click "Edit With Form" above to add content History and Infrastructure Operating Power Plants: 0 No geothermal plants listed. Add a new Operating Power Plant Developing Power Projects: 0

394

Separation Creek Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

Separation Creek Geothermal Area Separation Creek Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermal Resource Area: Separation Creek Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory and Environmental Issues 4 Exploration History 5 Well Field Description 6 Geology of the Area 7 Geofluid Geochemistry 8 NEPA-Related Analyses (0) 9 Exploration Activities (1) 10 References Area Overview Geothermal Area Profile Location: Oregon Exploration Region: Cascades GEA Development Phase: 2008 USGS Resource Estimate Mean Reservoir Temp: Estimated Reservoir Volume: Mean Capacity: Click "Edit With Form" above to add content History and Infrastructure Operating Power Plants: 0 No geothermal plants listed. Add a new Operating Power Plant Developing Power Projects: 0

395

Lassen Volcanic National Park Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

Lassen Volcanic National Park Geothermal Area Lassen Volcanic National Park Geothermal Area (Redirected from Lassen Volcanic National Park Area) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermal Resource Area: Lassen Volcanic National Park Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory and Environmental Issues 4 Exploration History 5 Well Field Description 6 Geology of the Area 7 Geofluid Geochemistry 8 NEPA-Related Analyses (0) 9 Exploration Activities (11) 10 References Area Overview Geothermal Area Profile Location: California Exploration Region: Cascades GEA Development Phase: 2008 USGS Resource Estimate Mean Reservoir Temp: Estimated Reservoir Volume: Mean Capacity: Click "Edit With Form" above to add content History and Infrastructure Operating Power Plants: 0

396

Lassen Volcanic National Park Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

Lassen Volcanic National Park Geothermal Area Lassen Volcanic National Park Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermal Resource Area: Lassen Volcanic National Park Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory and Environmental Issues 4 Exploration History 5 Well Field Description 6 Geology of the Area 7 Geofluid Geochemistry 8 NEPA-Related Analyses (0) 9 Exploration Activities (11) 10 References Area Overview Geothermal Area Profile Location: California Exploration Region: Cascades GEA Development Phase: 2008 USGS Resource Estimate Mean Reservoir Temp: Estimated Reservoir Volume: Mean Capacity: Click "Edit With Form" above to add content History and Infrastructure Operating Power Plants: 0 No geothermal plants listed. Add a new Operating Power Plant

397

Mt St Helens Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

Mt St Helens Geothermal Area Mt St Helens Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermal Resource Area: Mt St Helens Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory and Environmental Issues 4 Exploration History 5 Well Field Description 6 Geology of the Area 7 Geofluid Geochemistry 8 NEPA-Related Analyses (0) 9 Exploration Activities (8) 10 References Area Overview Geothermal Area Profile Location: Washington Exploration Region: Cascades GEA Development Phase: 2008 USGS Resource Estimate Mean Reservoir Temp: Estimated Reservoir Volume: Mean Capacity: Click "Edit With Form" above to add content History and Infrastructure Operating Power Plants: 0 No geothermal plants listed. Add a new Operating Power Plant Developing Power Projects: 0

398

Glass Buttes Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

Glass Buttes Geothermal Area Glass Buttes Geothermal Area (Redirected from Glass Buttes Area) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermal Resource Area: Glass Buttes Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory and Environmental Issues 4 Exploration History 5 Well Field Description 6 Geology of the Area 7 Geofluid Geochemistry 8 NEPA-Related Analyses (1) 9 Exploration Activities (14) 10 References Area Overview Geothermal Area Profile Location: Oregon Exploration Region: Cascades GEA Development Phase: 2008 USGS Resource Estimate Mean Reservoir Temp: Estimated Reservoir Volume: Mean Capacity: Click "Edit With Form" above to add content History and Infrastructure Operating Power Plants: 0 No geothermal plants listed. Add a new Operating Power Plant

399

Lester Meadow Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

Lester Meadow Geothermal Area Lester Meadow Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermal Resource Area: Lester Meadow Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory and Environmental Issues 4 Exploration History 5 Well Field Description 6 Geology of the Area 7 Geofluid Geochemistry 8 NEPA-Related Analyses (0) 9 Exploration Activities (3) 10 References Area Overview Geothermal Area Profile Location: Washington Exploration Region: Cascades GEA Development Phase: 2008 USGS Resource Estimate Mean Reservoir Temp: Estimated Reservoir Volume: Mean Capacity: Click "Edit With Form" above to add content History and Infrastructure Operating Power Plants: 0 No geothermal plants listed. Add a new Operating Power Plant Developing Power Projects: 0

400

Mt Ranier Geothermal Area | Open Energy Information  

Open Energy Info (EERE)

Mt Ranier Geothermal Area Mt Ranier Geothermal Area Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Geothermal Resource Area: Mt Ranier Geothermal Area Contents 1 Area Overview 2 History and Infrastructure 3 Regulatory and Environmental Issues 4 Exploration History 5 Well Field Description 6 Geology of the Area 7 Geofluid Geochemistry 8 NEPA-Related Analyses (0) 9 Exploration Activities (2) 10 References Area Overview Geothermal Area Profile Location: Washington Exploration Region: Cascades GEA Development Phase: 2008 USGS Resource Estimate Mean Reservoir Temp: Estimated Reservoir Volume: Mean Capacity: Click "Edit With Form" above to add content History and Infrastructure Operating Power Plants: 0 No geothermal plants listed. Add a new Operating Power Plant Developing Power Projects: 0

Note: This page contains sample records for the topic "region cascades gea" 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

2014 REGIONAL ECONOMIC OUTLOOK  

E-Print Network [OSTI]

2014 REGIONAL ECONOMIC OUTLOOK #12;2014 REGIONAL ECONOMIC OUTLOOK 2014 Overview The Cincinnati USA Partnership for Economic Development and the Northern Kentucky Chamber of Commerce are pleased to present the 2014 Regional Economic Outlook. This report was prepared by the Cincinnati USA Partnership's Regional

Boyce, Richard L.

402

A quantum cascade laser-based optical feedback cavity-enhanced absorption spectrometer for the simultaneous measurement ofCH4 and N2O in air  

Science Journals Connector (OSTI)

Optical feedback cavity-enhanced absorption spectroscopy (OF CEAS) has been demonstrated with a thermoelectrically cooled continuous wave distributed feedback quantum cascade laser (QCL) operating at wavelengths ...

D. J. Hamilton; A. J. Orr-Ewing

2011-03-01T23:59:59.000Z

403

Quantum Cascade Laser Spectroscopy and Photoinduced Chemistry of Al(CO)n Clusters in Helium Nanodroplets  

Science Journals Connector (OSTI)

Quantum Cascade Laser Spectroscopy and Photoinduced Chemistry of Al(CO)n Clusters in Helium Nanodroplets ... Only aluminum carbonyl clusters of the form Al(CO)n are observed in this study, and a future report will discuss the larger Alm(CO)n species. ... The QCL frequency is tuned by rotating a grating with a stepper motor (0.01 cm1 steps) or by scanning the cavity length continuously (?30 GHz tuning) by applying a 0100 V sine wave ramp to a piezo element. ...

Tao Liang; Steven D. Flynn; Alexander M. Morrison; Gary E. Douberly

2011-05-26T23:59:59.000Z

404

Cascaded spin motive force driven by the dynamics of the skyrmion lattice  

SciTech Connect (OSTI)

We numerically investigate the spin motive force (SMF) driven by the dynamics of a Skyrmion lattice. The rotating mode of the Skyrmion core excited by the AC magnetic field induces the large spin-dependent electric field near the core. Due to the collective dynamics of Skyrmion lattice, the measurable voltage is enhanced by the cascade effect of the SMF. The amplitude of the AC voltage is estimated to 30??V in a macroscopic sample, where 100 Skyrmions exist between two probes. We also investigate the SMF due to the dynamics of the helical magnetic state, where the enhancement of the SMF does not occur.

Ohe, Jun-ichiro; Shimada, Yuhki [Department of Physics, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510 (Japan)] [Department of Physics, Toho University, 2-2-1 Miyama, Funabashi, Chiba 274-8510 (Japan)

2013-12-09T23:59:59.000Z

405

Detection and measurement of electroreflectance on quantum cascade laser device using Fourier transform infrared microscope  

SciTech Connect (OSTI)

We demonstrate the use of a Fourier Transform Infrared microscope system to detect and measure electroreflectance (ER) from mid-infrared quantum cascade laser (QCL) device. To characterize intersubband transition (ISBT) energies in a functioning QCL device, a microscope is used to focus the probe on the QCL cleaved mirror. The measured ER spectra exhibit resonance features associated to ISBTs under applied electric field in agreement with the numerical calculations and comparable to observed photocurrent, and emission peaks. The method demonstrates the potential as a characterization tool for QCL devices.

Enobio, Eli Christopher I.; Ohtani, Keita; Ohno, Yuzo; Ohno, Hideo, E-mail: ohno@riec.tohoku.ac.jp [Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)] [Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577 (Japan)

2013-12-02T23:59:59.000Z

406

Improving proton-induced one-nucleon removal in intranuclear cascade  

E-Print Network [OSTI]

It is a well-established fact that intranuclear-cascade models generally fail to consistently reproduce the cross sections for one-proton and one-neutron removal from stable nuclei by a high-energy proton beam. We use simple shell-model calculations to investigate the reasons of this deficiency. We find that a refined description of the neutron skin and of the energy density in the nuclear surface is crucial for the aforementioned observables, and that neither ingredient is sufficient if taken separately. As a by-product, the predictions for removal of several nucleons are also improved by the refined treatment.

Davide Mancusi; Alain Boudard; Jaume Carbonell; Joseph Cugnon; Jean-Christophe David; Sylvie Leray

2014-11-17T23:59:59.000Z

407

Multi-wavelength surface emitting quantum cascade laser based on equivalent phase shift  

SciTech Connect (OSTI)

A novel surface emitting distributed feedback quantum cascade laser emitting around ????4.6??m is demonstrated by employing an equivalent phase shift (EPS) of quarter-wave (?/4). The EPS is fabricated through extending one sampling period by 50% in the center of a sampled Bragg grating. Single-lobed far-field radiation pattern with a low divergence angle of about 0.6??16.8 is obtained. Selective single-mode lasing with a mean side mode suppression ratio above 20?dB and wavelength coverage range of 72?nm is achieved simultaneously on a single wafer only by changing the sampling period.

Zhang, J. C., E-mail: zhangjinchuan@semi.ac.cn; Liu, F. Q., E-mail: fqliu@semi.ac.cn; Yao, D. Y.; Wang, L. J.; Yan, F. L.; Liu, J. Q.; Wang, Z. G. [Institute of Semiconductors, Key Laboratory of Semiconductor Materials Science, Chinese Academy of Sciences, Beijing, 100083, Peoples Republic of China and Beijing Key Laboratory of Low Dimensional Semiconductor Materials and Devices, Beijing 100083 (China)

2014-01-21T23:59:59.000Z

408

Standoff reflectionabsorption spectra of surface adsorbed explosives measured with pulsed quantum cascade lasers  

Science Journals Connector (OSTI)

Abstract We demonstrate a standoff detection scheme of surface adsorbed explosives based on the broadband quantum cascade laser (QCL) infrared reflectionabsorption spectroscopy and ultraviolet laser photodecomposition. We utilized a sub-second rapid-scan data acquisition scheme to record continuously scanned spectra which revealed the broad-band absorption features of surface adsorbed explosive molecules such as cyclotrimethylene trinitramine (RDX) and trinitrotoluene with a surface concentration of 1?g/cm2. The standoff QCL spectra perfectly reproduce the reflectance spectra obtained with a conventional Fourier transform infrared spectroscopy instrument. The conformation conversion of RDX molecules is also observed and studied.

Xunchen Liu; Charles W. Van Neste; Manisha Gupta; Ying Y. Tsui; Seonghwan Kim; Thomas Thundat

2014-01-01T23:59:59.000Z

409

An 8-{mu}m quantum cascade laserproduced by the metalorganic vapour phase epitaxy method  

SciTech Connect (OSTI)

An 8-{mu}m quantum cascade laser is fabricated by the metalorganic vapour phase epitaxy method. A scheme of vertical transitions in a structure consisting of three quantum wells is used. The laser operates in a pulsed regime at temperatures up to 250 K. The threshold current density was about 3 kA cm{sup -2} and increased up to 6 kA cm{sup -2} at 250 K. The 1-{mu}s pulse power in the multimode regime was 45 mW at 77 K.

Zasavitskii, I I; Pashkeev, D A [P N Lebedev Physical Institute, Russian Academy of Sciences, Moscow (Russian Federation); Marmalyuk, Aleksandr A; Ryaboshtan, Yu L [M.F. Stel'makh Polyus Research and Development Institute, Moscow (Russian Federation); Mikaelyan, G T [OJSC Research and Manufacturing Enterprise 'Inject', Saratov (Russian Federation)

2010-02-28T23:59:59.000Z

410

Role of collisional broadening in Monte Carlo simulations of terahertz quantum cascade lasers  

SciTech Connect (OSTI)

Using a generalized version of Fermi's golden rule, collisional broadening is self-consistently implemented into ensemble Monte Carlo carrier transport simulations, and its effect on the transport and optical properties of terahertz quantum cascade lasers is investigated. The inclusion of broadening yields improved agreement with the experiment, without a significant increase of the numerical load. Specifically, this effect is crucial for a correct modeling at low biases. In the lasing regime, broadening can lead to significantly reduced optical gain and output power, affecting the obtained current-voltage characteristics.

Matyas, Alpar; Lugli, Paolo; Jirauschek, Christian [Institute for Nanoelectronics, Technische Universitaet Muenchen, D-80333 Munich (Germany)] [Institute for Nanoelectronics, Technische Universitaet Muenchen, D-80333 Munich (Germany)

2013-01-07T23:59:59.000Z

411

Quantum Cascade Laser Development Efforts for Implementation into Chemical and Remote Sensing Systems  

SciTech Connect (OSTI)

Quantum cascade lasers (QCL) offer many desirable attributes as mid-infrared laser sources for chemical and remote sensing. Some key advantages are a narrow linewidth, wide bandwidth current modulation characteristics and moderate tunability (15 cm-1). Combined, these characteristics allow for applications to a wide variety of chemical and remote sensing techniques such as wavelength and frequency modulation based detection techniques, cavity enhanced point sensors as well as techniques such as LIDAR and DIAL. This paper will describe laser development efforts to enhance QCL frequency stabilization and QCL injection locking and to develop robust external cavity QCL designs.

Wojcik, Michael D.; Myers, Tanya L.; Taubman, Matthew S.; Cannon, Bret D.; Broocks, Bryan T.; Mosely, Trinesha

2004-12-01T23:59:59.000Z

412

Note: Switch-Mode Hybrid Current Controllers for Quantum Cascade Lasers  

SciTech Connect (OSTI)

Chemical sensing in the mid-infrared has been revolutionized by the advent of quantum cascade lasers. Their higher current and voltage demands compared to laser diodes however, negatively impact size, weight and power footprint for fieldable systems, particularly in hot environments. This letter presents a switch-mode/linear hybrid controller design, furnishing low-noise drive current up to 2 amperes at compliance voltages up to 15 volts, with noise levels close to the Johnson noise of the internal resistors. Current modulation from near zero to 1.8 Amps is also demonstrated at frequencies up to a kilohertz.

Taubman, Matthew S.

2013-01-07T23:59:59.000Z

413

Chirped laser dispersion spectroscopy using a directly modulated quantum cascade laser  

SciTech Connect (OSTI)

Chirped laser dispersion spectroscopy (CLaDS) utilizing direct modulation of a quantum cascade laser (QCL) is presented. By controlling the laser bias nearly single- and dual-sideband CLaDS operation can be realized in an extremely simplified optical setup with no external optical modulators. Capability of direct single-sideband modulation is a unique feature of QCLs that exhibit a low linewidth enhancement factor. The developed analytical model shows excellent agreement with the experimental, directly modulated CLaDS spectra. This method overcomes major technical limitations of mid-infrared CLaDS systems by allowing significantly higher modulation frequencies and eliminating optical fringes introduced by external modulators.

Hangauer, Andreas, E-mail: hangauer@princeton.edu; Nikodem, Michal; Wysocki, Gerard, E-mail: gwysocki@princeton.edu [Electrical Engineering Department, Princeton University, Princeton, New Jersey 08544 (United States)] [Electrical Engineering Department, Princeton University, Princeton, New Jersey 08544 (United States); Spinner, Georg [Electrical Engineering Department, Princeton University, Princeton, New Jersey 08544 (United States) [Electrical Engineering Department, Princeton University, Princeton, New Jersey 08544 (United States); Institute for Quantum Electronics, ETH Zurich, 8093 Zurich (Switzerland)

2013-11-04T23:59:59.000Z

414

Standoff Hyperspectral Imaging of Explosives Residues Using Broadly Tunable External Cavity Quantum Cascade Laser Illumination  

SciTech Connect (OSTI)

We describe experimental results on the detection of explosives residues using active hyperspectral imaging by illumination of the target surface using an external cavity quantum cascade laser (ECQCL) and imaging using a room temperature microbolometer camera. The active hyperspectral imaging technique forms an image hypercube by recording one image for each tuning step of the ECQCL. The resulting hyperspectral image contains the full absorption spectrum produced by the illumination laser at each pixel in the image which can then be used to identify the explosive type and relative quantity using spectral identification approaches developed initially in the remote sensing community.

Bernacki, Bruce E.; Phillips, Mark C.

2010-05-01T23:59:59.000Z

415

Room temperature continuous wave operation of quantum cascade lasers with 12.5% wall plug efficiency  

SciTech Connect (OSTI)

An InP based quantum cascade laser heterostructure emitting at 4.6 {mu}m was grown with gas-source molecular beam epitaxy. The wafer was processed into a conventional double-channel ridge waveguide geometry with ridge widths of 19.7 and 10.6 {mu}m without semi-insulating InP regrowth. An uncoated, narrow ridge device with a 4.8 mm cavity length was epilayer down bonded to a diamond submount and exhibits 2.5 W maximum output power with a wall plug efficiency of 12.5% at room temperature in continuous wave operation.

Bai, Y.; Slivken, S.; Darvish, S. R.; Razeghi, M. [Center for Quantum Devices, Department of Electrical Engineering and Computer Science, Northwestern University, Evanston, Illinois 60208 (United States)

2008-07-14T23:59:59.000Z

416

Equivalent circuit-level model and improvement of terahertz quantum cascade lasers  

Science Journals Connector (OSTI)

An equivalent circuit-level model of terahertz (THz) quantum cascade lasers (QCLs) is developed by using rate equations. This model can be employed to investigate the characteristics of THz QCLs accurately and to improve their design. We use the circuit-level model to analyse a new active structure, which can improve the performance of THz QCLs by means of enhancing carrier injection. The simulation result shows that THz QCLs with the new active structure have a much higher performance compared with conventional THz QCLs. The high-performance THz QCLs are expected to be operated at higher temperatures.

Wei Zhou; Shaobin Liu; Jie Wu; Xiaoliu Zhang; Wu Tang

2014-01-01T23:59:59.000Z

417

Period doubling cascade in glow discharges: Local versus global differential conductivity  

Science Journals Connector (OSTI)

Short planar glow discharges coupled to a resistive layer exhibit a wealth of spontaneous spatiotemporal patterns. Due to similarities with other pattern forming systems that are described by reaction-diffusion models, several authors have tried to derive such models from discharge physics. We investigate the temporal oscillations of the discharge system and find a cascade of period doubling events. This shows that the inner structure of the discharge is more complex than can be described by a two-component reaction-diffusion-model with negative differential conductivity. We also derive an alternative reduced model.

Danijela D. ija?i?, Ute Ebert, and Ismail Rafatov

2004-11-23T23:59:59.000Z

418

Bioinspired Approach to Multienzyme Cascade System Construction for Efficient Carbon Dioxide Reduction  

Science Journals Connector (OSTI)

Bioinspired Approach to Multienzyme Cascade System Construction for Efficient Carbon Dioxide Reduction ... In our previous studies, spatially separated enzymatic systems, mimicking natural enzyme organization, were developed by using several kinds of organicinorganic hybrid microcapsules. ... Briefly, immobilized-enzyme-containing solution (1 mL, 50 mM PBS, pH 7.0) was bubbled with CO2 gas for 0.5 h, and then NADH solution (1 mL, 50 mM PBS, pH 7.0) was added to initiate the reaction. ...

Xiaoli Wang; Zheng Li; Jiafu Shi; Hong Wu; Zhongyi Jiang; Wenyan Zhang; Xiaokai Song; Qinghong Ai

2014-02-12T23:59:59.000Z

419

Infrared near-field spectroscopy of trace explosives using an external cavity quantum cascade laser  

SciTech Connect (OSTI)

Utilizing a broadly-tunable external cavity quantum cascade laser for scattering-type scanning near-field optical microscopy (s-SNOM), we measure infrared spectra of explosives particles by probing characteristic nitro-group resonances in the 7.1-7.9 m wavelength range. Measurements are presented with spectral resolution of 0.25 cm-1, spatial resolution of 25 nm, <100 attomolar sensitivity, and at a rapid acquisition time of 90 s per spectrum. We demonstrate high reproducibility of the acquired s-SNOM spectra with very high signal-to-noise ratios and relative noise of <0.02 in self-homodyne detection.

Craig, Ian M.; Taubman, Matthew S.; Lea, Alan S.; Phillips, Mark C.; Josberger, Erik E.; Raschke, Markus Bernd

2013-12-16T23:59:59.000Z

420

Hyperspectral Microscopy of Explosives Particles Using an External Cavity Quantum Cascade Laser  

SciTech Connect (OSTI)

Using infrared hyperspectral imaging, we demonstrate microscopy of small particles of the explosives compounds RDX, tetryl, and PETN with near diffraction-limited performance. The custom microscope apparatus includes an external cavity quantum cascade laser illuminator scanned over its tuning range of 9.13-10.53 m in four seconds, coupled with a microbolometer focal plane array to record infrared transmission images. We use the hyperspectral microscopy technique to study the infrared absorption spectra of individual explosives particles, and demonstrate sub-nanogram detection limits.

Phillips, Mark C.; Bernacki, Bruce E.

2012-12-26T23:59:59.000Z

Note: This page contains sample records for the topic "region cascades gea" from the National Library of EnergyBeta (NLEBeta).
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to obtain the most current and comprehensive results.


421

Cascade | EMSL  

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

of formation yields a model with quantitative agreement for the benchmark minerals brucite, magnesite, nesquehonite, and hydromagnesite. The model shows how small differences...

422
423

Cascade Locks  

E-Print Network [OSTI]

trip location DISCLAIMER Neither the State of Washington, 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 State of Washington or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the State of Washington or any agency thereof.

Skamania Lodge; David K. Norman; Jaretta M. Roloff; David K. Normanassistant State Geologist; David K. Norman; Jaretta M. Roloff

424

Modulation Extension Control of Hybrid Cascaded H-Bridge Multilevel Converters with 7-Level Fundamental Frequency Switching Scheme  

SciTech Connect (OSTI)

This paper presents a modulation extension control algorithm for hybrid cascaded H-bridge multilevel converters. The hybrid cascaded H-bridge multilevel motor drive using only a single DC source for each phase is promising for high power motor drive applications since it can greatly decrease the number of required DC power supplies, has high quality output power due to its high number of output levels, and has high conversion efficiency and low thermal stress by using fundamental frequency switching scheme. But one disadvantage of the 7-level fundamental frequency switching scheme is that its modulation index range is too narrow when capacitor's voltage balance is maintained. The proposed modulation extension control algorithm can greatly increase capacitors' charging time and decrease the capacitors' discharging time by injecting triplen harmonics to extend the modulation index range of the hybrid cascaded H-bridge multilevel converters.

Du, Zhong [ORNL; Ozpineci, Burak [ORNL; Tolbert, Leon M [ORNL

2007-01-01T23:59:59.000Z

425

LDRD final report on high power broadly tunable Mid-IR quantum cascade lasers for improved chemical species detection.  

SciTech Connect (OSTI)

The goal of our project was to examine a novel quantum cascade laser design that should inherently increase the output power of the laser while simultaneously providing a broad tuning range. Such a laser source enables multiple chemical species identification with a single laser and/or very broad frequency coverage with a small number of different lasers, thus reducing the size and cost of laser based chemical detection systems. In our design concept, the discrete states in quantum cascade lasers are replaced by minibands made of multiple closely spaced electron levels. To facilitate the arduous task of designing miniband-to-miniband quantum cascade lasers, we developed a program that works in conjunction with our existing modeling software to completely automate the design process. Laser designs were grown, characterized, and iterated. The details of the automated design program and the measurement results are summarized in this report.

Wanke, Michael Clement; Hudgens, James J.; Fuller, Charles T.; Samora, Sally; Klem, John Frederick; Young, Erik W.

2006-01-01T23:59:59.000Z

426

Solar-assisted auto-cascade heat pump cycle with zeotropic mixture R32/R290 for small water heaters  

Science Journals Connector (OSTI)

Abstract In this study, a novel solar-assisted auto-cascade heat pump cycle (SAHPC) operating with the zeotropic mixture of R32/R290 for small water heaters is proposed. In the SAHPC system, a cascade heat exchanger (CHEX) associated with a phase separator is used to achieve auto cascade cycle and enhance the overall system performance. The performances of the SAHPC are evaluated by using the developed mathematical model, and then compared with the conventional air-sourced heat pump cycle (CAHPC). Simulation results show the SAHPC has 4.239.85% and 4.379.68% improvements in COP and volumetric heating capacity compared with those of the CAHPC, respectively, under the same operating conditions. However, the improvement of performance of this novel cycle largely depends on the absorbing heat ratio and the zeotropic composition. It is expected that this new cycle will be beneficial to developing dual-source coupled heat pump applications.

Xiaolong Lv; Gang Yan; Jianlin Yu

2015-01-01T23:59:59.000Z

427

Inverse cascade and symmetry breaking in rapidly-rotating Boussinesq convection  

E-Print Network [OSTI]

In this paper we present numerical simulations of rapidly-rotating Rayleigh-B\\'enard convection in the Boussinesq approximation with stress-free boundary conditions. At moderately low Rossby number and large Rayleigh number, we show that a large-scale depth-invariant flow is formed, reminiscent of the condensate state observed in two-dimensional flows. We show that the large-scale circulation shares many similarities with the so-called vortex, or slow-mode, of forced rotating turbulence. Our investigations show that at a fixed rotation rate the large-scale vortex is only observed for a finite range of Rayleigh numbers, as the quasi-two-dimensional nature of the flow disappears at very high Rayleigh numbers. We observe slow vortex merging events and find a non-local inverse cascade of energy in addition to the regular direct cascade associated with fast small-scale turbulent motions. Finally, we show that cyclonic structures are dominant in the small-scale turbulent flow and this symmetry breaking persists in ...

Favier, B; Proctor, M R E

2014-01-01T23:59:59.000Z

428

First Evidence For Atmospheric Neutrino-Induced Cascades with the IceCube Detector  

E-Print Network [OSTI]

IceCube is an all-flavor, cubic kilometer neutrino telescope currently under construction in the deep glacial ice at the South Pole. Its embedded optical sensors detect Cherenkov light from charged particles produced in neutrino interactions in the ice. For several years IceCube has been detecting muon tracks from charged-current muon neutrino interactions. However, IceCube has yet to observe the electromagnetic or hadronic particle showers or "cascades" initiated by charged-current or neutral-current neutrino interactions. The first detection of such an event signature is expected to come from the known flux of atmospheric electron and muon neutrinos. A search for atmospheric neutrino-induced cascades was performed using 275.46 days of data from IceCube's 22-string configuration. Reconstruction and background rejection techniques were developed to reach, for the first time, a signal-to-background ratio ~1. Above a reconstructed energy of 5 TeV, 12 candidate events were observed in the full dataset. The signa...

D'Agostino, Michelangelo

2009-01-01T23:59:59.000Z

429

Kinetic cascade beyond MHD of solar wind turbulence in two-dimensional hybrid simulations  

E-Print Network [OSTI]

The nature of solar wind turbulence in the dissipation range at scales much smaller than the large MHD scales remains under debate. Here a two-dimensional model based on the hybrid code abbreviated as A.I.K.E.F. is presented, which treats massive ions as particles obeying the kinetic Vlasov equation and massless electrons as a neutralizing fluid. Up to a certain wavenumber in the MHD regime, the numerical system is initialized by assuming a superposition of isotropic Alfv\\'en waves with amplitudes that follow the empirically confirmed spectral law of Kolmogorov. Then turbulence develops and energy cascades into the dispersive spectral range, where also dissipative effects occur. Under typical solar wind conditions, weak turbulence develops as a superposition of normal modes in the kinetic regime. Spectral analysis in the direction parallel to the background magnetic field reveals a cascade of left-handed Alfv\\'en/ion-cyclotron waves up to wave vectors where their resonant absorption sets in, as well as a cont...

Verscharen, Daniel; Motschmann, Uwe; Mller, Joachim

2012-01-01T23:59:59.000Z

430

THEORETICAL INVESTIGATION OF MICROSTRUCTURE EVOLUTION AND DEFORMATION OF ZIRCONIUM UNDER CASCADE DAMAGE CONDITIONS  

SciTech Connect (OSTI)

This work is based on our reaction-diffusion model of radiation growth of Zr-based materials proposed recently in [1]. In [1], the equations for the strain rates in unloaded pure crystal under cascade damage conditions of, e.g., neutron or heavy-ion irradiation were derived as functions of dislocation densities, which include contributions from dislocation loops, and spatial distribution of their Burgers vectors. The model takes into account the intra-cascade clustering of self-interstitial atoms and their one-dimensional diffusion; explains the growth stages, including the break-away growth of pre-annealed samples; and accounts for some striking observations, such as of negative strain in prismatic direction, and co-existence of vacancy- and interstitial-type prismatic loops. In this report, the change of dislocation densities due to accumulation of sessile dislocation loops is taken into account explicitly to investigate the dose dependence of radiation growth. The dose dependence of climb rates of dislocations is calculated, which is important for the climb-induced glide model of radiation creep. The results of fitting the model to available experimental data and some numerical calculations of the strain behavior of Zr for different initial dislocation structures are presented and discussed. The computer code RIMD-ZR.V1 (Radiation Induced Microstructure and Deformation of Zr) developed is described and attached to this report.

Barashev, Alexander V [ORNL; Golubov, Stanislav I [ORNL; Stoller, Roger E [ORNL

2012-06-01T23:59:59.000Z

431

Demystifying the PeV cascades in IceCube: Less (energy) is more (events)  

Science Journals Connector (OSTI)

The IceCube neutrino observatory has detected two cascade events with energies near 1PeV [A. Ishihara Proceedings of Neutrino 2012 Conference, http://neu2012.kek.jp/index.html; M. Aartsen etal. (IceCube Collaboration) Phys. Rev. Lett. 111, 021103 (2013)]. Without invoking new physics, we analyze the source of these neutrinos. We show that atmospheric conventional neutrinos and cosmogenic neutrinos (those produced in the propagation of ultra-high-energy cosmic rays) are strongly disfavored. For atmospheric prompt neutrinos or a diffuse background of neutrinos produced in astrophysical objects, the situation is less clear. We show that there is tension with observed data, but that the details depend on the least-known aspects of the IceCube analysis. Very likely, prompt neutrinos are disfavored and astrophysical neutrinos are plausible. We demonstrate that the fastest way to reveal the origin of the observed PeV neutrinos is to search for neutrino cascades in the range below 1PeV, for which dedicated analyses with high sensitivity have yet to appear, and where many more events could be found.

Ranjan Laha; John F. Beacom; Basudeb Dasgupta; Shunsaku Horiuchi; Kohta Murase

2013-08-21T23:59:59.000Z

432

Investigation of cascade-type falling liquid-film along first wall of laser-fusion reactor  

Science Journals Connector (OSTI)

To protect the first wall of an inertia fusion reactor from extremely high heat flux, X-rays, alpha particles and fuel debris caused by a nuclear fusion reaction, a cascade-type falling liquid-film flow is proposed as a liquid-wall concept. The flow visualization experiment to investigate the feasibility of this liquid-wall concept has been conducted. The preliminary numerical simulation results suggest that the current cascade structure design should be improved because less thermal-mixing is expected. The cascade-type structure has, therefore, been redesigned. This new cascade-type first wall consists of a liquid reservoir which has a free-surface to maintain a constant water head in the rear, and connects to a slit composed of two plates, i.e., the first wall is connected to a slit which is partially made up of the first wall to begin with it. The numerical simulations were performed on the new cascade-type first wall and they show the stable liquid-film flow on it. Moreover, the POP (proof-of-principle) flow visualization experiments, which satisfy the Weber number coincident condition, are carried out using water as the working fluid. By comparing the numerical and experimental results, it was found that the liquid-film flow with 35mm thickness could be stably established. According to these results for the new cascade-type first wall concept, it was confirmed that the coolant flow rate and the thickness of the liquid-film could be controlled if the Weber number coincident condition was satisfied.

T. Kunugi; T. Nakai; Z. Kawara; T. Norimatsu; Y. Kozaki

2008-01-01T23:59:59.000Z

433

Western Regional Partnership Overview  

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

Regional Partnership Overview Regional Partnership Overview June 2013 Briefing Overview  WRP Background  Importance of Region  WRP Tribal Relations Committee  WRP Energy Committee WRP Region's Uniqueness  5 states stretching from the Great Plains to the Pacific Ocean  Diverse terrain ranging from desert valleys to forested mountains  Significant State Trust Landholdings  Approximately 188 Federally recognized Tribes  Significant amounts of Federally managed land  According to GSA 2004 study, WRP states range from 41.8% - 84.5% of total state land WRP Region's Importance to DoD  Extensive Training Ranges  Interconnected ground/air ranges provide unmatched warfighter training opportunities

434

Regional Comparisons, Spatial Aggregation,  

Gasoline and Diesel Fuel Update (EIA)

Regional Regional Comparisons, Spatial Aggregation, and Asymmetry of Price Pass-Through in U.S. Gasoline Markets MICHAEL YE*, JOHN ZYREN**, JOANNE SHORE**, AND MICHAEL BURDETTE** Abstract Spot to retail price pass-through behavior of the U.S. gasoline market was investigated at the national and regional levels, using weekly wholesale and retail motor gasoline prices from January 2000 to the present. Asymmetric pass-through was found across all regions, with faster pass-through when prices are rising. Pass-through patterns, in terms of speed and time for completion, were found to vary from region to region. Spatial aggregation was investigated at the national level and the East Coast with the aggregated cumulative pass-through being greater than the volume-weighted regional pass-through when spot prices increase. These results are useful to the petroleum industry, consumers,

435

Conditions for Capacitor Voltage Regulation in a Five-Level Cascade Multilevel Inverter: Application to Voltage-Boost in a PM Drive  

E-Print Network [OSTI]

Conditions for Capacitor Voltage Regulation in a Five-Level Cascade Multilevel Inverter Abstract-- A cascade multilevel inverter is a power electronic device built to synthesize a desired AC voltage from several levels of DC voltages. Such inverters have been the subject of research in the last

Tolbert, Leon M.

436

Abstract-A fault detection and reconfiguration technique for a cascaded H-bridge 11-level inverter drives during faulty condition  

E-Print Network [OSTI]

of multilevel inverters for electric drive application have been discussed in [1]. The cascaded MLID is a general fit for large automotive all-electric drives because of the high VA rating possible and because structure of a three-phase cascaded multilevel inverter drive for an electric vehicle is illustrated in Fig

Tolbert, Leon M.

437

Copyright 2008 IEEE. Reprinted from Hui Ren, Student Member, IEEE and Ian Dobson, Fellow, IEEE; Using Transmission Line Outage Data to Estimate Cascading Failure Propagation in an  

E-Print Network [OSTI]

; Using Transmission Line Outage Data to Estimate Cascading Failure Propagation in an Electric Power ON CIRCUITS AND SYSTEMS--II: EXPRESS BRIEFS, VOL. 55, NO. 9, SEPTEMBER 2008 927 Using Transmission Line Outage, IEEE, and Ian Dobson, Fellow, IEEE Abstract--We study cascading transmission line outages recorded over

438

About Rocky Mountain Region  

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

Rates About the Rocky Mountain Region RM Office The Platte River Power Authority in Colorado, Nebraska Public Power District, Kansas Electric Power Cooperative and Wyoming...

439

Eight-band kp modeling of InAs/InGaAsSb type-II W-design quantum well structures for interband cascade lasers emitting in a broad range of mid infrared  

SciTech Connect (OSTI)

Band structure properties of the type-II W-design AlSb/InAs/GaIn(As)Sb/InAs/AlSb quantum wells have been investigated theoretically in a systematic manner and with respect to their use in the active region of interband cascade laser for a broad range of emission in mid infrared between below 3 to beyond 10??m. Eight-band kp approach has been utilized to calculate the electronic subbands. The fundamental optical transition energy and the corresponding oscillator strength have been determined in function of the thickness of InAs and GaIn(As)Sb layers and the composition of the latter. There have been considered active structures on two types of relevant substrates, GaSb and InAs, introducing slightly modified strain conditions. Additionally, the effect of external electric field has been taken into account to simulate the conditions occurring in the operational devices. The results show that introducing arsenic as fourth element into the valence band well of the type-II W-design system, and then altering its composition, can efficiently enhance the transition oscillator strength and allow additionally increasing the emission wavelength, which makes this solution prospective for improved performance and long wavelength interband cascade lasers.

Ryczko, K.; S?k, G.; Misiewicz, J. [Institute of Physics, Wroc?aw University of Technology, Wybrze?e Wyspia?skiego 27, 50-370 Wroc?aw (Poland)

2013-12-14T23:59:59.000Z

440

Meson cascade in the atmosphere, uncertainties in calculating the fluxes of high-energy muons, and data of direct measurements  

Science Journals Connector (OSTI)

A new calculation of the atmospheric fluxes of cosmic-ray hadrons and muons in the energy range 10104...GeV is performed on the basis of the method for solving nuclear-cascade equations with allowance for a nons...

A. A. Kochanov; T. S. Sinegovskaya; S. I. Sinegovsky

2007-11-01T23:59:59.000Z

Note: This page contains sample records for the topic "region cascades gea" 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

Many of the enzymes, receptors and eicosanoid metabo-lites of the arachidonate cascade (FIG. 1) are key thera-  

E-Print Network [OSTI]

Many of the enzymes, receptors and eicosanoid metabo- lites of the arachidonate cascade (FIG. 1 of cardiovascular diseases such as hypertension and stroke13­16 . The epoxygenase CYP enzymes generate diminishing their beneficial cardiovascular properties20,21 . Inhibition of this enzyme is therefore

Hammock, Bruce D.

442

IEEE TRANSACTIONS ON SMART GRID, VOL. 5, NO. 3, MAY 2014 1183 A Coordinated Multi-Switch Attack for Cascading  

E-Print Network [OSTI]

IEEE TRANSACTIONS ON SMART GRID, VOL. 5, NO. 3, MAY 2014 1183 A Coordinated Multi-Switch Attack for Cascading Failures in Smart Grid Shan Liu, Bo Chen, Takis Zourntos, Deepa Kundur, and Karen Butler-Purry Abstract--This paper explores distributed smart grid attack strategies to destabilize power system

Kundur, Deepa

443

IEEE TRANSACTIONS ON INFORMATION FORENSICS AND SECURITY, VOL. 9, NO. 3, MARCH 2014 451 Integrated Security Analysis on Cascading  

E-Print Network [OSTI]

complex network systems, including com- munication network, social network and smart grid, have become, we simulated attacks on different components (buses and branches) in the grid and evaluated of different loading and overloading situations on cascading failures was also evaluated by testing different

He, Haibo

444

Calculation of gain and luminescence spectra of quantum-cascade laser structures taking into account asymmetric emission line broadening  

SciTech Connect (OSTI)

The energy levels, wave functions, and matrix elements of optical dipole transitions are calculated numerically for superlattice quantum-cascade structures. The effect of spectral broadening on the shape of emission spectra is estimated and semiphenomenological asymmetric profiles of emission line broadening are proposed. It is shown that the electroluminescence spectra well agree with the calculated spontaneous recombination spectra. (lasers)

Ushakov, D V; Manak, I S [Belarusian State University, Minsk (Belarus); Kononenko, V K [B.I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, Minsk (Belarus)

2010-05-26T23:59:59.000Z

445

An AlGaAsGaAs quantum cascade laser operating with a thermoelectric cooler for spectroscopy of NH3  

E-Print Network [OSTI]

out using a compact thermo-electrically cooled laser package. The QCL described here is designedAn AlGaAs­GaAs quantum cascade laser operating with a thermoelectric cooler for spectroscopy of NH3. Langford b a Department of Electronics and Electrical Engineering, Rankine Building, University of Glasgow

446

Real time ammonia detection in exhaled human breath using a distributed feedback quantum cascade laser based sensor  

E-Print Network [OSTI]

, thermoelectrically cooled, distributed feedback quantum cascade laser (DFB-QCL) based sensor platform concentration measurements are performed with a 2f wavelength modulation quartz enhanced photoacoustic exchange inside a compact QEPAS gas cell. An air-cooled DFB-QCL was designed to target the interference

447

Non-Dominated Sorting Binary Differential Evolution for the Multi-Objective Optimization of Cascading Failures Protection in Complex Networks  

E-Print Network [OSTI]

) is then proposed. The numerical application to the topological structure of the 380 kV Italian power transmission.g. transmission line switch off) of critical infrastructures (e.g. power grids, telecommunication networks network proves the benefits of the improvements. Keywords: complex networks, cascading failures, line

Boyer, Edmond

448

IEEE Power Engineering Society General Meeting, Tampa FL USA, June 2007 Where is the edge for cascading failure?: challenges  

E-Print Network [OSTI]

quantify the blackout risk. We summarize initial testing on power system simulations of cascading overloads when a sequence of failures suc- cessively weaken the electric power transmission system and make overloads, hidden failures of protection systems, software, control or operator error, flawed

Dobson, Ian

449

Building America Whole-House Solutions for Existing Homes: Cascade Apartments- Deep Energy Multifamily Retrofit (Fact Sheet)  

Broader source: Energy.gov [DOE]

In December of 2009-10, King County Housing Authority implemented energy retrofit improvements in the Cascade multifamily community, located in Kent, Washington, which resulted in annual energy cost savings of 22%, improved comfort and air quality for residents, and increased durability of the units.

450

Validation of the Poisson Stochastic Radiative Transfer Model Against Cloud Cascade Models  

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

Poisson Stochastic Radiative Transfer Poisson Stochastic Radiative Transfer Model Against Cloud Cascade Models T. B. Zhuravleva Institute of Atmospheric Optics Tomsk, Russia A. Marshak National Aeronautics and Space Administration Goddard Space Flight Center Greenbelt, Maryland Background Starting from a very simple stochastic cloud model by Mullamaa et al. (1972), several different stochastic models have been developed to describe radiative transfer regime in single-layer broken clouds (Kargin 1984; Titov 1990; Malvagi and Pomraning 1992; Barker et al. 1992; Malvagi et al. 1993; Kargin and Prigarin 1994; Prigarin and Titov 1996; Marshak et al. 1998; Prigarin et al. 1998, 2001; Evans et al. 1999, 2001). Recently Kassianov (2003a) generalized the Titov's (1990) stochastic model

451

A loophole to the universal photon spectrum in electromagnetic cascades: application to the "cosmological lithium problem"  

E-Print Network [OSTI]

The standard theory of electromagnetic cascades onto a photon background predicts a quasi-universal shape for the resulting non-thermal photon spectrum. This has been applied to very disparate fields, including non-thermal big bang nucleosynthesis (BBN). However, once the energy of the injected photons falls below the pair-production threshold the spectral shape is very different, a fact that has been overlooked in past literature. This loophole may have important phenomenological consequences, since it generically alters the BBN bounds on non-thermal relics: for instance it allows to re-open the possibility of purely electromagnetic solutions to the so-called "cosmological lithium problem", which were thought to be excluded by other cosmological constraints. We show this with a proof-of-principle example and a simple particle physics model, compared with previous literature.

Vivian Poulin; Pasquale D. Serpico

2015-02-04T23:59:59.000Z

452

A loophole to the universal photon spectrum in electromagnetic cascades: application to the "cosmological lithium problem"  

E-Print Network [OSTI]

The standard theory of electromagnetic cascades onto a photon background predicts a quasi-universal shape for the resulting non-thermal photon spectrum. This has been applied to very disparate fields, including non-thermal big bang nucleosynthesis (BBN). However, once the energy of the injected photons falls below the pair-production threshold the spectral shape is very different, a fact that has been overlooked in past literature. This loophole may have important phenomenological consequences, since it generically alters the BBN bounds on non-thermal relics: for instance it allows to re-open the possibility of purely electromagnetic solutions to the so-called "cosmological lithium problem", which were thought to be excluded by other cosmological constraints. We show this with a proof-of-principle example and a simple particle physics model, compared with previous literature.

Poulin, Vivian

2015-01-01T23:59:59.000Z

453

High-resolution multi-heterodyne spectroscopy based on Fabry-Perot quantum cascade lasers  

SciTech Connect (OSTI)

In this Letter, we present a method of performing broadband mid-infrared spectroscopy with conventional, free-running, continuous wave Fabry-Perot quantum cascade lasers (FP-QCLs). The measurement method is based on multi-heterodyne down-conversion of optical signals. The sample transmission spectrum probed by one multi-mode FP-QCL is down-converted to the radio-frequency domain through an optical multi-heterodyne process using a second FP-QCL as the local oscillator. Both a broadband multi-mode spectral measurement as well as high-resolution (?15?MHz) spectroscopy of molecular absorption are demonstrated and show great potential for development of high performance FP-laser-based spectrometers for chemical sensing.

Wang, Yin; Wang, Wen; Wysocki, Gerard, E-mail: gwysocki@princeton.edu [Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08540 (United States); Soskind, Michael G. [Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08540 (United States); Department of Electrical Engineering, Rutgers University, New Brunswick, New Jersy 08901 (United States)

2014-01-20T23:59:59.000Z

454

Optimized switching scheme of cascaded H-bridge multilevel inverter using PSO  

Science Journals Connector (OSTI)

Abstract The paper uses particle swarm optimization (PSO) to determine the optimum switching angles of cascaded H-bridge multilevel inverter (CH-MLI) so as to produce the required fundamental voltage and reduce the harmonic content. This is done by solving the transcendental equations characterizing the harmonic content. The validity of the proposed method is verified through simulation studies for three-phase, five-level CH-MLI. To compare the results obtained using PSO, the simulation studies have been extended for three-phase, five-level CH-MLI using sinusoidal pulse width modulation (SPWM). The results obtained using PSO are found superior as compared to SPWM in terms of total harmonic distortion at different modulation indices.

Vivek Kumar Gupta; R. Mahanty

2015-01-01T23:59:59.000Z

455

Cascade utilization of chemical energy of natural gas in an improved CRGT cycle  

Science Journals Connector (OSTI)

In this paper three advanced power systems: the chemically recuperated gas turbine (CRGT) cycle, the steam injected gas turbine (STIG) cycle and the combined cycle (CC), are investigated and compared by means of exergy analysis. Making use of the energy level concept, cascaded use of the chemical exergy of natural gas in a CRGT cycle is clarified, and its performance of the utilization of chemical energy is evaluated. Based on this evaluation, a new CRGT cycle is designed to convert the exergy of natural gas more efficiently into electrical power. As a result, the exergy efficiency of the new CRGT cycle is about 55%, which is 8 percentage points higher than that of the reference CRGT cycle. The analysis gave a better interpretation of the inefficiencies of the CRGT cycle and suggested improvement options. This new approach can be used to design innovative energy systems.

Wei Han; Hongguang Jin; Na Zhang; Xiaosong Zhang

2007-01-01T23:59:59.000Z

456

Application of multi-subband self-consistent energy balance method to terahertz quantum cascade lasers  

Science Journals Connector (OSTI)

We present simulation results for two resonant phonon terahertz quantum cascade lasers using a self-consistent energy balance model, which determines the electron temperature for each conduction subband. These temperatures, along with the electron populations and scattering rates, are determined in a manner similar to previously published models. However, the presented model is able to converge through the use of an algorithm that appears to be robust. The predicted individual subband electron temperatures, population densities and scattering rates are compared to previously published Monte Carlo and experimental studies for both lasers, where subband temperature variations were observed. These quantities were chosen since they provided the only comparison to modeling results from other studies.

Philip Slingerland; Christopher Baird; Robert H Giles

2012-01-01T23:59:59.000Z

457

Frequency and phaselock control of a 3 THz quantum cascade laser.  

SciTech Connect (OSTI)

We have locked the frequency of a 3 THz quantum cascade laser (QCL) to that of a far-infrared gas laser with a tunable microwave offset frequency. The locked QCL line shape is essentially Gaussian, with linewidths of 65 and 141 kHz at the -3 and -10 dB levels, respectively. The lock condition can be maintained indefinitely, without requiring temperature or bias current regulation of the QCL other than that provided by the lock error signal. The result demonstrates that a terahertz QCL can be frequency controlled with 1-part-in-108 accuracy, which is a factor of 100 better than that needed for a local oscillator in a heterodyne receiver for atmospheric and astronomic spectroscopy.

Williams, Benjamin S. (Massachusetts Institute of Technology, Cambridge, MA); Hu, Qing (Massachusetts Institute of Technology, Cambridge, MA); Reno, John Louis; Boreiko, R. T. (University of Colorado, Boulder, CO); Betz, A. L. (University of Colorado, Boulder, CO); Kumar, S. (Massachusetts Institute of Technology, Cambridge, MA)

2005-03-01T23:59:59.000Z

458

Calculation of the microscopic parameters of a self-induced transparency modelocked quantum cascade laser  

Science Journals Connector (OSTI)

A model to calculate the microscopic parameters of self-induced transparency (SIT) modelocked quantum cascade lasers (QCLs) is presented and the parameters are then calculated for a particular structure. These parameters are then used to calculate the gain to absorption ratio that is required to determine the required ratio of gain periods to absorbing periods that must be grown in order to obtain stable modelocked pulses. The modelocked pulse parameters, along with the stability limits are then calculated as the ratio of gain to absorption varies. For the SIT modelocked QCL design that we examined, we found that three to five gain periods must be grown for each absorbing period in order to ensure stable operation.

Muhammad Anisuzzaman Talukder; Curtis R. Menyuk

2013-01-01T23:59:59.000Z

459

A CO2 sensor based upon a continuous-wave thermoelectrically-cooled quantum cascade laser  

Science Journals Connector (OSTI)

A CO2 sensor based upon a continuous-wave thermoelectrically-cooled distributed feedback quantum cascade laser operating between 2305 and 2310cm?1 and a 54.2cm long optical cell has been developed. Two approaches for direct absorption spectroscopy have been evaluated and applied for monitoring of the CO2 concentration in gas lines and ambient laboratory air. In the first approach optical transmittance was derived from the single channel laser intensity, whilst in the second approach a ratio of signal and reference laser intensities (balanced detection) was used. The optimum residual absorption standard deviation was estimated to be 1.9נ10?4 for 100 averages of 1ms duration and 0.1cm?1 scans over the P(46) CO2 absorption line of the ?3 vibrational band at 2306.926cm?1. A CO2 detection limit (1 standard deviation) of 36ppb was estimated for 0.1s average and balanced detection.

Vasili L. Kasyutich; Philip A. Martin

2011-01-01T23:59:59.000Z

460

Measurements of the linewidth of a continuous-wave distributed feedback quantum cascade laser  

Science Journals Connector (OSTI)

Two-sample (Allan) variance with a modified algorithm was applied to the determination of the experimental linewidth of a thermoelectrically-cooled continuous-wave distributed feedback quantum cascade laser at a wavelength of 4.333?m. From successive laser transmittance scans over the CO2 ?3, (0111?0110) P(33) absorption line at 2307.653cm?1, two-sample variances were calculated for the laser frequency difference between different points on the sides of the absorption peak. From the minimum two-sample variance of the laser frequency difference between two adjacent points (5?s between the points) on the same side of the absorption line the experimental laser linewidth was estimated to be less than 36(7) kHz at a laser power of ~25mW, a laser current of 976mA and a laser temperature of +19.5C.

Vasili L. Kasyutich; Philip A. Martin

2011-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "region cascades gea" 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.


461

Reflection-Absorption Infrared Spectroscopy of Thin Films Using an External Cavity Quantum Cascade Laser  

SciTech Connect (OSTI)

We present experimental demonstrations using a broadly tunable external cavity quantum cascade laser (ECQCL) to perform Reflection-Absorption InfraRed Spectroscopy (RAIRS) of thin layers and residues on surfaces. The ECQCL compliance voltage was used to measure fluctuations in the ECQCL output power and improve the performance of the RAIRS measurements. Absorption spectra from self-assembled monolayers of a fluorinated alkane thiol and a thiol carboxylic acid were measured and compared with FTIR measurements. RAIRS spectra of the explosive compounds PETN, RDX, and tetryl deposited on gold substrates were also measured. Rapid measurement times and low noise were demonstrated, with < 1E-3 absorbance noise for a 10 second measurement time.

Phillips, Mark C.; Craig, Ian M.; Blake, Thomas A.

2013-02-04T23:59:59.000Z

462

Rate equations analysis of a dual-wavelength quantum cascade laser  

Science Journals Connector (OSTI)

Abstract Based on a four-level rate equations model, we carry out a detailed analysis of the two modes of a mid-infrared quantum cascade laser operating simultaneously on two laser lines having a common upper level. Analytical solutions are obtained for the steady-states and the stability analysis of these predicts that, depending on the injected current, the device lases on either one of the two modes or on both wavelengths simultaneously. We also show through numerical simulations that the injected current influences significantly the population inversions and photon numbers dynamics trajectory of a two mode laser where the higher the current the shorter the time needed to reach saturation and therefore steady state operation.

A. Hamadou; J.-L. Thobel; S. Lamari

2013-01-01T23:59:59.000Z

463

Effect of Doppler broadening on Autler-Townes splitting in the molecular cascade excitation scheme  

Science Journals Connector (OSTI)

Theoretical analysis of the Autler-Townes splitting pattern in a three-level cascade excitation of a Doppler-broadened sample reveals that the observed Autler-Townes splitting is not only a function of the coupling-laser Rabi frequency, as in the homogeneously broadened case, but can also strongly depend on the wavenumber ratio of the coupling and probe lasers. Utilizing a steady-state density matrix formalism, we derive exact expressions for the populations of the intermediate and upper levels for a homogeneously broadened system. In the limit of a weak probe field, analytical expressions for Doppler-broadened excitation spectra from the intermediate and upper levels are derived. Using these expressions, we investigate the critical role of Doppler broadening on the observation of Autler-Townes splitting and its asymptotic behavior as a function of the coupling Rabi frequency for counterpropagating and copropagating configurations for different wavenumber ratios of the lasers.

E. Ahmed and A. M. Lyyra

2007-11-09T23:59:59.000Z

464

Adaptive Selective Harmonic Minimization Based on ANNs for Cascade Multilevel Inverters With Varying DC Sources  

SciTech Connect (OSTI)

A new approach for modulation of an 11-level cascade multilevel inverter using selective harmonic elimination is presented in this paper. The dc sources feeding the multilevel inverter are considered to be varying in time, and the switching angles are adapted to the dc source variation. This method uses genetic algorithms to obtain switching angles offline for different dc source values. Then, artificial neural networks are used to determine the switching angles that correspond to the real-time values of the dc sources for each phase. This implies that each one of the dc sources of this topology can have different values at any time, but the output fundamental voltage will stay constant and the harmonic content will still meet the specifications. The modulating switching angles are updated at each cycle of the output fundamental voltage. This paper gives details on the method in addition to simulation and experimental results.

Filho, Faete [ORNL; Maia, Helder Z [UFMS, Department of Electrical Engineering; Mateus, Tiago Henrique D [ORNL; Ozpineci, Burak [ORNL; Tolbert, Leon M [ORNL; Pinto, Joao Onofre P [ORNL

2013-01-01T23:59:59.000Z

465

Cascade of elimination and emergence of pure cooperation in coevolutionary games on networks  

Science Journals Connector (OSTI)

We propose a coevolutionary game to study cooperative behavior in the presence of catastrophic phenomenon. We incorporate tolerance to elimination of individuals in network games where individuals update their strategies synchronously, and there are no birth of individuals and stochastic effects. We find that an avalanchelike death process can arise when defection strategies exist and individuals are vulnerable to deficiency of profits. Strikingly, we observe that, after such a cascading process terminates, cooperators are the sole survivors regardless of the game types and of the connection patterns among individuals as determined by the network topology. Cooperation thus becomes the optimal strategy and absolutely outperforms defection. Our results can yield insights into evolution of cooperation in the presence of catastrophic events in social and natural systems.

Wen-Xu Wang; Rui Yang; Ying-Cheng Lai

2010-03-30T23:59:59.000Z

466

Widely tuneable scattering-type scanning near-field optical microscopy using pulsed quantum cascade lasers  

SciTech Connect (OSTI)

We demonstrate the use of a pulsed quantum cascade laser, wavelength tuneable between 6 and 10??m, with a scattering-type scanning near-field optical microscope (s-SNOM). A simple method for calculating the signal-to-noise ratio (SNR) of the s-SNOM measurement is presented. For pulsed lasers, the SNR is shown to be highly dependent on the degree of synchronization between the laser pulse and the sampling circuitry; in measurements on a gold sample, the SNR is 26 with good synchronization and less than 1 without. Simulations and experimental s-SNOM images, with a resolution of 100?nm, corresponding to ?/80, and an acquisition time of less than 90 s, are presented as proof of concept. They show the change in the field profile of plasmon-resonant broadband antennas when they are excited with wavelengths of 7.9 and 9.5??m.

Yoxall, Edward, E-mail: edward.yoxall@imperial.ac.uk; Rahmani, Mohsen; Maier, Stefan A.; Phillips, Chris C. [The Blackett Laboratory, Department of Physics, Imperial College London, London SW7 2AZ (United Kingdom)] [The Blackett Laboratory, Department of Physics, Imperial College London, London SW7 2AZ (United Kingdom); Navarro-Ca, Miguel [Optical and Semiconductor Devices Group, Department of Electrical and Electronic Engineering, Imperial College London, London SW7 2BT (United Kingdom)] [Optical and Semiconductor Devices Group, Department of Electrical and Electronic Engineering, Imperial College London, London SW7 2BT (United Kingdom)

2013-11-18T23:59:59.000Z

467

Information cascade, Kirmans ant colony model, and kinetic Ising model  

Science Journals Connector (OSTI)

Abstract In this paper, we discuss a voting model in which voters can obtain information from a finite number of previous voters. There exist three groups of voters: (i) digital herders and independent voters, (ii) analog herders and independent voters, and (iii) tanh -type herders. In our previous paper Hisakado and Mori (2011), we used the mean field approximation for case (i). In that study, if the reference number r is above three, phase transition occurs and the solution converges to one of the equilibria. However, the conclusion is different from mean field approximation. In this paper, we show that the solution oscillates between the two states. A good (bad) equilibrium is where a majority of r select the correct (wrong) candidate. In this paper, we show that there is no phase transition when r is finite. If the annealing schedule is adequately slow from finite r to infinite r , the voting rate converges only to the good equilibrium. In case (ii), the state of reference votes is equivalent to that of Kirmans ant colony model, and it follows beta binomial distribution. In case (iii), we show that the model is equivalent to the finite-size kinetic Ising model. If the voters are rational, a simple herding experiment of information cascade is conducted. Information cascade results from the quenching of the kinetic Ising model. As case (i) is the limit of case (iii) when tanh function becomes a step function, the phase transition can be observed in infinite size limit. We can confirm that there is no phase transition when the reference number r is finite.

Masato Hisakado; Shintaro Mori

2015-01-01T23:59:59.000Z

468

Innovative biomass to power conversion systems based on cascaded supercritical CO2 Brayton cycles  

Science Journals Connector (OSTI)

Abstract In the small to medium power range the main technologies for the conversion of biomass sources into electricity are based either on reciprocating internal combustion or organic Rankine cycle engines. Relatively low energy conversion efficiencies are obtained in both systems due to the thermodynamic losses in the conversion of biomass into syngas in the former, and to the high temperature difference in the heat transfer between combustion gases and working fluid in the latter. The aim of this paper is to demonstrate that higher efficiencies in the conversion of biomass sources into electricity can be obtained using systems based on the supercritical closed CO2 Brayton cycles (s-CO2). The s-CO2 system analysed here includes two cascaded supercritical CO2 cycles which enable to overcome the intrinsic limitation of the single cycle in the effective utilization of the whole heat available from flue gases. Both part-flow and simple supercritical CO2 cycle configurations are considered and four boiler arrangements are investigated to explore the thermodynamic performance of such systems. These power plant configurations, which were never explored in the literature for biomass conversion into electricity, are demonstrated here to be viable options to increase the energy conversion efficiency of small-to-medium biomass fired power plants. Results of the optimization procedure show that a maximum biomass to electricity conversion efficiency of 36% can be achieved using the cascaded configuration including a part flow topping cycle, which is approximately 10%-points higher than that of the existing biomass power plants in the small to medium power range.

Giovanni Manente; Andrea Lazzaretto

2014-01-01T23:59:59.000Z

469

Design of cascaded low cost solar cell with CuO substrate  

SciTech Connect (OSTI)

For many years the main focus of R and D in solar cells was the development of high-efficiency solar convertors. However with solar technology beginning to be a part of national grids and stand-alone power supplies for variety of individual customers, the emphasis has changed, namely, the cost per kilowatt- hour (kW-hr) started to be an important figure of merit. Although Si does dominate the market of solar convertors, this material has total cost of kilowatt-hour much higher than what the power grid is providing presently to customers. It is well known that the cost of raw semiconductor material is a major factor in formulation of the final cost of a solar cell. That motivated us to search and design a novel solar cell using cheap materials. The new p-i-n solar cell consists of hetero-structure cascade of materials with step by step decreasing energy gap. Since the lattice constant of these three materials do differ not more than 2%, the more expensive epitaxial fabrication methods can be used as well. It should be emphasized that designed solar cell is not a cascade of three solar cells connected in series. Our market study shows that Si solar panel which costs $250400 / m{sup 2} leads to a cost of $0.120.30 / kW-hr. To the contrary, CuO based solar cells with Cadmium compounds on top, would cost $100 / m{sup 2}. This will allow the novel solar cell to produce electricity at a cost of $0.060.08 / kW-hr.

Samson, Mil'shtein; Anup, Pillai; Shiv, Sharma; Garo, Yessayan [Advanced Electronic Technology Center, ECE Dept., University of Massachusetts, Lowell, MA-01851 (United States)

2013-12-04T23:59:59.000Z

470

Cascade of failures in coupled network systems with multiple support-dependence relations  

Science Journals Connector (OSTI)

We study, both analytically and numerically, the cascade of failures in two coupled network systems A and B, where multiple support-dependence relations are randomly built between nodes of networks A and B. In our model we assume that each node in one network can function only if it has at least a single support link connecting it to a functional node in the other network. We assume that networks A and B have (i) sizes NA and NB, (ii) degree distributions of connectivity links PA(k) and PB(k), (iii) degree distributions of support links P?A(k) and P?B(k), and (iv) random attack removes (1-RA)NA and (1-RB)NB nodes form the networks A and B, respectively. We find the fractions of nodes ??A and ??B which remain functional (giant component) at the end of the cascade process in networks A and B in terms of the generating functions of the degree distributions of their connectivity and support links. In a special case of Erd?s-Rnyi networks with average degrees a and b in networks A and B, respectively, and Poisson distributions of support links with average degrees a? and b? in networks A and B, respectively, ??A=RA[1-exp(-a???B)][1-exp(-a??A)] and ??B=RB[1-exp(-b???A)][1-exp(-b??B)]. In the limit of a??? and b???, both networks become independent, and our model becomes equivalent to a random attack on a single Erd?s-Rnyi network. We also test our theory on two coupled scale-free networks, and find good agreement with the simulations.

Jia Shao; Sergey V. Buldyrev; Shlomo Havlin; H. Eugene Stanley

2011-03-29T23:59:59.000Z

471

HYDROGEN REGIONAL INFRASTRUCTURE PROGRAM  

E-Print Network [OSTI]

to serve as "go-to" organization to catalyze PA Hydrogen and Fuel Cell Economy development #12;FundingHYDROGEN REGIONAL INFRASTRUCTURE PROGRAM IN PENNSYLVANIA HYDROGEN REGIONAL INFRASTRUCTURE PROGRAM IN PENNSYLVANIA Melissa Klingenberg, PhDMelissa Klingenberg, PhD #12;Hydrogen ProgramHydrogen Program Air Products

472

Regional Analysis Briefs  

Reports and Publications (EIA)

Regional Analysis Briefs (RABs) provide an overview of specific regions that play an important role in world energy markets, either directly or indirectly. These briefs cover areas that are currently major producers (Caspian Sea), have geopolitical importance (South China Sea), or may have future potential as producers or transit areas (East Africa, Eastern Mediterranean).

2028-01-01T23:59:59.000Z

473

Regional Competitions - EERE Commercialization Office  

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

Regional Competitions Six Regional Clean Energy Business Plan Competitions are taking place across the country- representing all of the United States' distinct regions. The...

474

Infrared Scattering Scanning Near-Field Optical Microscopy Using An External Cavity Quantum Cascade Laser For Nanoscale Chemical Imaging And Spectroscopy of Explosive Residues  

SciTech Connect (OSTI)

Infrared scattering scanning near-field optical microscopy (s-SNOM) is an apertureless superfocusing technique that uses the antenna properties of a conducting atomic force microscope (AFM) tip to achieve infrared spatial resolution below the diffraction limit. The instrument can be used either in imaging mode, where a fixed wavelength light source is tuned to a molecular resonance and the AFM raster scans an image, or in spectroscopy mode where the AFM is held stationary over a feature of interest and the light frequency is varied to obtain a spectrum. In either case, a strong, stable, coherent infrared source is required. Here we demonstrate the integration of a broadly tunable external cavity quantum cascade laser (ECQCL) into an s-SNOM and use it to obtain infrared spectra of microcrystals of chemicals adsorbed onto gold substrates. Residues of the explosive compound tetryl was deposited onto gold substrates. s-SNOM experiments were performed in the 1260-1400 cm?1 tuning range of the ECQCL, corresponding to the NO2 symmetric stretch vibrational fingerprint region. Vibrational infrared spectra were collected on individual chemical domains with a collection area of *500nm2 and compared to ensemble averaged far-field reflection-absorption infrared spectroscopy (RAIRS) results.

Craig, Ian M.; Phillips, Mark C.; Taubman, Matthew S.; Josberger, Erik E.; Raschke, Markus Bernd

2013-02-04T23:59:59.000Z

475

Regional Planning | Data.gov  

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

Regional Planning Regional Planning Ocean Data Tools Technical Guide Map Gallery Regional Planning Feedback Ocean You are here Data.gov » Communities » Ocean Regional Planning Efforts Alias (field_alias) Apply California, Oregon, Washington Regional Ocean Partnership West Coast Governors' Alliance Regional Data Portal In Development U.S. Virgin Islands, Puerto Rico Regional Ocean Partnership U.S. Caribbean Regional Ocean Partnership-currently being formally established Regional Data Portal To be developed Georgia, Florida, North Carolina, South Carolina Regional Ocean Partnership Governors' South Atlantic Alliance Regional Data Portal Currently in development American Samoa, Commonwealth of the Northern Mariana Islands (CNMI), Federated States of Micronesia, Guam, Hawaii, Marshall Islands, Palau

476

the Regional Development Corporation  

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

carry out this work, CPO partners carry out this work, CPO partners with the Los Alamos National Laboratory Foundation for education, the Regional Development Corporation for economic development, and the regional United Way organizations for community giving. Education Los Alamos National Security (LANS) invests more than $1 million each year to enhance regional educational opportunities in science, technology, engineering, and math (STEM) education. Education Focus Areas Our education commitments address four focus areas: * Workforce Development * Student Internships * Teacher and Faculty Professional Development * Public Understanding of Science In 2011, more than 1,100 students

477

Regional and Global Data  

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

Products > Regional/Global Products > Regional/Global Regional and Global Data Biogeochemical Dynamics Data Regional and global biogeochemical dynamics data can be used to improve our understanding of the structure and function of various ecosystems; to enable prediction across spatial and temporal scales; and to parameterize and validate terrestrial ecosystem models. The ORNL DAAC compiles, archives, and distributes more than 150 products from the following projects: Climate Collections Hydroclimatology Collections ISLSCP II Project Net Primary Productivity (NPP) River Discharge (RIVDIS) Russian Land Cover (RLC) Soil Collections Vegetation Collections Vegetation-Ecosystem Modeling (VEMAP) Climate Collections Climate collections include measured and modeled values for variables such as temperature, precipitation, humidity, radiation, wind velocity, and

478

Regional Districts (Texas)  

Broader source: Energy.gov [DOE]

Adjacent Water Control and Improvement Districts and Municipal Utility Districts can opt to form a Regional District to oversee water issues. Such districts may be created:(1) to purchase, own,...

479

Supersonic Free-jet Quantum Cascade Laser Measurements of v4 for CF3(35)Cl and CF3(37)Cl and FTS Measurements from 400 to 1260 cm-1  

SciTech Connect (OSTI)

A supersonic free-jet spectrum of the ?4 band of CF3Cl has been measured using a quantum cascade laser system. Those measurements were combined with a low temperature (-67 C) FTS spectrum of the region 1060 to 1260 cm-1 and with room temperature FTS measurements down to 400 cm-1 to give improved values for the rovibrational constants for the v1, v2, v3, 2v3, 2v5, v4, and v5 states of CF335Cl and CF337Cl. The principal perturbation found by earlier investigators in the v1 band is treated as a very weak Coriolis interaction at several avoided crossings of the rotational levels of the v1 state and the 2v5 state with kl < 0. None of the other vibrational states showed any signs of perturbations. With these new measurements we now have high resolution data on all of the fundamental vibrational states except v6.

Kelly, James F.; Maki, Arthur; Blake, Thomas A.; Sams, Robert L.

2008-11-01T23:59:59.000Z

480

Exergy analysis of a vapour compression-absorption cascaded refrigeration system using modified Gouy-Stodola equation  

Science Journals Connector (OSTI)

In the present study, the performance of vapour compression-absorption cascaded refrigeration system (VCACRS) is studied with modified Gouy-Stodola equation and the results are compared with the classical approach of exergy evaluation. The quantitative difference in two approaches is presented which necessitates the need to employ modified approach. The expressions are formulated for effective temperature and real irreversible loss for different components of VCACRS. The overall performance of system can be improved by increasing the evaporator and generator temperature and by decreasing the absorber, cascade condenser and condenser temperature. Coefficient of structural bonds (CSB) analysis shows evaporator is relatively more sensitive to change in its temperature as compared with the other components.

Vaibhav Jain; Surendra Singh Kachhwaha; Gulshan Sachdeva

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "region cascades gea" 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.


481

Three-Phase Modular Cascaded H-Bridge Multilevel Inverter with Individual MPPT for Grid-Connected Photovoltaic Systems  

SciTech Connect (OSTI)

A three-phase modular cascaded H-bridge multilevel inverter for a grid-connected photovoltaic (PV) system is presented in this paper. To maximize the solar energy extraction of each PV string, an individual maximum power point tracking (MPPT) control scheme is applied, which allows the independent control of each dc-link voltage. PV mismatches may introduce unbalanced power supplied to the three-phase system. To solve this issue, a control scheme with modulation compensation is proposed. The three-phase modular cascaded multilevel inverter prototype has been built. Each H-bridge is connected to a 185 W solar panel. Simulation and experimental results are presented to validate the proposed ideas.

Xiao, Bailu [ORNL; Hang, Lijun [ORNL; Riley, Cameron [University of Tennessee, Knoxville (UTK); Tolbert, Leon M [ORNL; Ozpineci, Burak [ORNL

2013-01-01T23:59:59.000Z

482

Short-term cascaded hydroelectric system scheduling based on chaotic particle swarm optimization using improved logistic map  

Science Journals Connector (OSTI)

In order to solve the model of short-term cascaded hydroelectric system scheduling, a novel chaotic particle swarm optimization (CPSO) algorithm using improved logistic map is introduced, which uses the water discharge as the decision variables combined with the death penalty function. According to the principle of maximum power generation, the proposed approach makes use of the ergodicity, symmetry and stochastic property of improved logistic chaotic map for enhancing the performance of particle swarm optimization (PSO) algorithm. The new hybrid method has been examined and tested on two test functions and a practical cascaded hydroelectric system. The experimental results show that the effectiveness and robustness of the proposed CPSO algorithm in comparison with other traditional algorithms.

Yaoyao He; Shanlin Yang; Qifa Xu

2013-01-01T23:59:59.000Z

483

Mid-infrared trace-gas sensing with a quasi- continuous-wave Peltier-cooled distributed feedback quantum cascade laser  

Science Journals Connector (OSTI)

A recently developed distributed feedback quantum cascade laser (QCL) capable of thermoelectric-cooled (TEC ... at ?9?m is used to perform laser chemical sensing by tunable infrared spectroscopy. A ... extend th...

D. Weidmann; F.K. Tittel; T. Aellen; M. Beck; D. Hofstetter; J. Faist

2004-11-01T23:59:59.000Z

484

Optimization of a compact photoacoustic quantum cascade laser spectrometer for atmospheric flux measurements: application to the detection of methane and nitrous oxide  

Science Journals Connector (OSTI)

Room temperature (RT) quantum cascade lasers (QCL) are now available even in ... in the 8?m range. The first laser had already been used to calibrate the...4...with a 1s integration time per point was demonstrat...

A. Grossel; V. Zninari; B. Parvitte; L. Joly; D. Courtois

2007-08-01T23:59:59.000Z

485

Cavity-enhanced optical feedback-assisted photo-acoustic spectroscopy with a 10.4?m external cavity quantum cascade laser  

Science Journals Connector (OSTI)

An ultra-sensitive photo-acoustic spectrometer using a 10.4?m broadly tunable mid-IR external cavity quantum cascade laser (EC-QCL) coupled with optical feedback ... reflectivity mirrors was developed and tested...

A. Kachanov; S. Koulikov; F. K. Tittel

2013-01-01T23:59:59.000Z

486

Sub-part-per-billion detection of nitric oxide in air using a thermoelectrically cooled mid-infrared quantum cascade laser spectrometer  

Science Journals Connector (OSTI)

Non-cryogenic, laser-absorption spectroscopy in the mid-infrared has ... (quantum cascade laser operated in pulsed mode at 5.26... by operating under pulsing conditions...

D.D. Nelson; J.H. Shorter; J.B. McManus; M.S. Zahniser

2002-09-01T23:59:59.000Z

487

Comparison of a quantum cascade laser used in both cw and pulsed modes. Application to the study of SO2 lines around 9?m  

Science Journals Connector (OSTI)

The same quantum cascade laser spectrometer working around 9?m was used ... modes to compare their own characteristics. The laser emitting in continuous-wave mode was mainly...2...ro-vibrational lines. This work...

B. Grouiez; B. Parvitte; L. Joly; D. Courtois; V. Zeninari

2008-02-01T23:59:59.000Z

488

Faraday rotation spectrometer with sub-second response time fordetection of nitric oxide using a cw DFB quantum cascade laser at5.33 ?m  

Science Journals Connector (OSTI)

A Faraday modulation spectrometer for sensitive and fast detection of nitric oxide at 5.33 ?m utilizing a room temperature continuous wave distributed feedback quantum cascade laser and a Peltier cooled MCT detec...

P. Kluczynski; S. Lundqvist; J. Westberg; O. Axner

2011-05-01T23:59:59.000Z

489

Generation of high-energy vacuum UV femtosecond pulses by multiple-beam cascaded four-wave mixing in a transparent solid  

Science Journals Connector (OSTI)

The generation of ultrashort vacuum UV (VUV) pulses by nondegenerate cascaded four-wave mixing of femtosecond pulses in a thin slide of a large band-gap transparent solid is...

Silva, Joo L; Crespo, Helder M; Weigand, Rosa

2011-01-01T23:59:59.000Z

490

Direct utilization of geothermal heat in cascade application to aquaculture and greenhouse systems at Navarro College. Annual report, January 1984-September 1984  

SciTech Connect (OSTI)

Progress is reported on a project to use the 130/sup 0/F geothermal resource in central Texas. The system for cascading geothermal energy through aquaculture and greenhouse systems was completed and the first shrimp harvest was held. (MHR)

Smith, K.

1984-09-01T23:59:59.000Z

491

Synthesis and determination of the absolute configuration of Armatol A through a polyepoxide cyclization cascade : revision of the proposed structures of Armatols A-F  

E-Print Network [OSTI]

Cyclization Cascades Leading to the Tricyclic Fragment of Armatol A The synthesis of the fused 6,7,7-tricycle of armatol A was investigated. Fragments containing both a ketone and an aldehyde for subsequent fragment coupling ...

Underwood, Brian Saxton

2011-01-01T23:59:59.000Z

492

Selection of potential IAEA inspection strategies involving cascade access at the Portsmouth Gas Centrifuge Enrichment Plant (GCEP)  

SciTech Connect (OSTI)

This report has been prepared as a US contribution to Team 4 of the Hexapartite Safeguards Project. It provides to the Team 4 participants one example of an approach, which has been used in the United States, to developing a range of safeguards strategies involving differing degrees of access to cascade areas of centrifuge enrichment plants. Its purpose is to facilitate the work of other Hexapartite participants in completing Task II of Team 4's terms of reference. The scope of this report is limited to identifying safeguards approaches for the Portsmouth Gas Centrifuge Enrichment Plant (GCEP) which involve differing degrees of access to the cascade area. This report provides a method for selecting cascade access inspection strategies at GCEP which appear promising for more detailed evaluation. It is quite important to note, however, that the effectiveness and practicability of these strategies have not been established at the present. In addition, some strategies have been included on the basis of very preliminary calculations and considerations which have not been validated. Thus, some of these strategies may ultimately be rejected because they prove to be impracticable. Considerations of cost and the possible transfer of information and technology related to the production of enriched uranium will also be pertinent in considering the degrees and frequency of access to the cascade areas of centrifuge enrichment plants. This report describes the process for combining technical measures, implementation approaches and objectives to arrive at the total number of theoretically possible combinations. It then describes how these combinations may be reduced in a series of steps to a number that is more manageable for detailed evaluation. The process is shown schematically.

Not Available

1981-04-13T23:59:59.000Z

493

New Gas-Phase Cascade Reactions of Stabilized Phosphorus Ylides Leading to Ring-Fused Indoles and to Quinolines  

Science Journals Connector (OSTI)

New Gas-Phase Cascade Reactions of Stabilized Phosphorus Ylides Leading to Ring-Fused Indoles and to Quinolines ... These latter products are representatives of rather uncommon fused ring systems, but the furo[2,3-c]carbazole system is present in the natural product eustifoline D isolated from Murraya euchrestifolia Hayata, a shrub found in Taiwan,(15) and a synthesis of this natural product using the present approach is currently in progress. ...

R. Alan Aitken; Lorna Murray

2008-11-04T23:59:59.000Z

494

Regional Retail Gasoline Prices  

Gasoline and Diesel Fuel Update (EIA)

7 7 Notes: Retail gasoline prices, like those for distillate fuels, have hit record prices nationally and in several regions this year. The national average regular gasoline price peaked at $1.68 per gallon in mid-June, but quickly declined, and now stands at $1.45, 17 cents higher than a year ago. Two regions, in particular, experienced sharp gasoline price runups this year. California, which often has some of the highest prices in the nation, saw prices peak near $1.85 in mid-September, while the Midwest had average prices over $1.87 in mid-June. Local prices at some stations in both areas hit levels well over $2.00 per gallon. The reasons for the regional price runups differed significantly. In the Midwest, the introduction of Phase 2 RFG was hampered by low stocks,

495

regional | OpenEI  

Open Energy Info (EERE)

regional regional Dataset Summary Description The UK Department of Energy and Climate Change (DECC) releases annual statistics on domestic and industrial/commercial electricity and gas consumption (and number of meters) at the Middle Layer Super Output Authority (MLSOA) and Intermediate Geography Zone (IGZ) level (there are over 950 of these subregions throughout England, Scotland and Wales). Both MLSOAs (England and Wales) and IGZs (Scotland) include a minimum of approximately 2,000 households. Source UK Department of Energy and Climate Change (DECC) Date Released March 01st, 2008 (6 years ago) Date Updated Unknown Keywords Electricity Consumption gas regional UK Data application/zip icon Guidance document for interpreting data (zip, 1.2 MiB) application/vnd.ms-excel icon Excel file: 2005 MLSOA and IGZ gas and electricity (xls, 10 MiB)

496

Establishing Regional Resource Centers  

Wind Powering America (EERE)

Establishing Regional Resource Centers Establishing Regional Resource Centers July 25, 2013 Coordinator: Welcome and thank you for standing by. At this time all participants are in a listen only mode. To ask a question later during the question and answer session please press star then 1 on your touchtone phone. Today's conference is being recorded. If you have any objections you may disconnect. And I would like to turn it over to Mr. Jonathan Bartlett. Sir, you may begin. Jonathan Bartlett: Thank you very much. This is Jonathan Bartlett from the Department of Energy's Wind and Water Power Technologies Office. Today's WPA Webinar will be on the subject of establishing regional resource centers. I will be joined by Ian Baring-Gould at the National Renewable Energy Laboratory and the

497

Developing new theoretical models of the formation of atomic collision cascades and subcascades in irradiated solids  

SciTech Connect (OSTI)

A new theoretical model is developed for the investigation of atomic collision cascades and subcascades in irradiated solids consisting of atoms of a single type. The model is based on an analytical description of the elastic collisions between moving atoms knocked out of the crystal lattice sites and the immobile atoms of the lattice. The description is based on the linear kinetic Boltzmann equation describing the retardation of primary recoil atoms (PRAs) in irradiated solids. The laws of conservation for the total number and the kinetic energy of moving atoms, which follow from the kinetic Boltzmann equation, are analyzed using the proposed model. An analytical solution is obtained for the stationary kinetic Boltzmann equation, which describes the retardation of PRAs for a given source responsible for their production. A kinetic equation for the moving atoms and the corresponding laws of conservation are also analyzed with allowance for the binding energy of atoms at the crystal lattice sites. A criterion for determining the threshold energy of subcascade formation in irradiated solids is formulated. Based on this criterion, the threshold energy of subcascade formation is calculated using the Thomas-Fermi potential. Formulas are presented for determining the mean size and number of subcascades formed in a solid as functions of the PRA energy.

Metelkin, E. V.; Ryazanov, A. I., E-mail: ryazanoff@comail.ru; Semenov, E. V. [Russian Research Center Kurchatov Institute (Russian Federation)

2008-09-15T23:59:59.000Z

498

Enhancement of existing geothermal resource utilization by cascading to intensive aquaculture  

SciTech Connect (OSTI)

A demonstration high rate aquaculture production system utilizing a cascaded geothermal resource was designed, constructed and operated to fulfill the objectives of this project. Analysis of the energy and water balances for the system indicated that the addition of an Aquaculture Facility expanded the use of the existing resource. This expanded use in no way affected the up- stream processes. Analysis of the system`s energy and water requirements indicated that the present resource was under-utilized and could be expanded. Energy requirements appeared more limiting than water use, but the existing system could be expanded to a culture volume of 72,000 gal. This system would have a potential production capacity of 93,600 lb/yr with a potential market value of $280,00/yr. Based on the results of this study, the heat remaining in the geothermal fluid from one square foot of operating greenhouse is sufficient to support six gallons of culture water for a high density aquaculture facility. Thus, the over 1.5M ft{sup 2} of existing greenhouse space in New Mexico, has the potential to create an aquaculture industry of nearly 9M gal. This translates to an annual production potential of 11.7M lb with a market value of $35.lM.

Zachritz, W.H., II; Polka, R.; Schoenmackers

1996-04-01T23:59:59.000Z

499

Optimization of the output and efficiency of a high power cascaded arc hydrogen plasma source  

SciTech Connect (OSTI)

The operation of a cascaded arc hydrogen plasma source was experimentally investigated to provide an empirical basis for the scaling of this source to higher plasma fluxes and efficiencies. The flux and efficiency were determined as a function of the input power, discharge channel diameter, and hydrogen gas flow rate. Measurements of the pressure in the arc channel show that the flow is well described by Poiseuille flow and that the effective heavy particle temperature is approximately 0.8 eV. Interpretation of the measured I-V data in terms of a one-parameter model shows that the plasma production is proportional to the input power, to the square root of the hydrogen flow rate, and is independent of the channel diameter. The observed scaling shows that the dominant power loss mechanism inside the arc channel is one that scales with the effective volume of the plasma in the discharge channel. Measurements on the plasma output with Thomson scattering confirm the linear dependence of the plasma production on the input power. Extrapolation of these results shows that (without a magnetic field) an improvement in the plasma production by a factor of 10 over where it was in van Rooij et al. [Appl. Phys. Lett. 90, 121501 (2007)] should be possible.

Vijvers, W. A. J.; Gils, C. A. J. van; Goedheer, W. J.; Meiden, H. J. van der; Veremiyenko, V. P.; Westerhout, J.; Lopes Cardozo, N. J.; Rooij, G. J. van [FOM-Institute for Plasma Physics Rijnhuizen, Association EURATOM-FOM, Trilateral Euregio Cluster, P.O. Box 1207, 3430 BE Nieuwegein (Netherlands); Schram, D. C. [Department of Applied Physics, Eindhoven University of Technology, P.O. Box 513, 5600 MB Eindhoven (Netherlands)

2008-09-15T23:59:59.000Z

500

Nonlinear effects in collision cascades and high energy shock waves during ta-C:H growth  

SciTech Connect (OSTI)

The surface topography of hydrogenated tetrahedral amorphous carbon (ta-C:H) is critical for various applications such as microelectromechanical devices, magnetic and optical storage devices, and medical implants. The surface topography of ta-C:H films deposited by distributed electron cyclotron resonance plasma from C{sub 2}H{sub 2} gas precursor was investigated. The effects of pressure, together with ion flux and energy, are studied by atomic force microscopy in relation to the structural evolution of the films. The results are compared with the predictions of the Edward-Wilkinson model [Proc. R. Soc. London, Ser. A 44, 1039 (1966)] recently proposed to account for ta-C:H growth and with previous interpretations based on hypersonic shock waves. The random hillocks observed on the smooth surfaces of ta-C:H films deposited at high pressure are thought to result from the interference of high energy shock waves triggered by C{sub 4}H{sub x}{sup +} ions that produce overlapping collision cascades and induce nonlinear effects.

Piazza, F.; Resto, O.; Morell, G. [Department of Physics, University of Puerto Rico, P.O. Box 23343, San Juan, 00931 (Puerto Rico)

2007-07-01T23:59:59.000Z