National Library of Energy BETA

Sample records for multiple energy carriers

  1. Intrinsic carrier multiplication efficiency in bulk Si crystals...

    Office of Scientific and Technical Information (OSTI)

    We estimated the carrier multiplication efficiency in the most common solar-cell material, ... of carriers quantitatively, which are crucial for the design of the solar cells. ...

  2. Carrier Comments | Department of Energy

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

    Carrier Comments Carrier Comments United Technologies Climate, Controls, and Security and its Carrier business would like to submit the following comments to the proposed questions as well as additional commentary as requested and referenced in the RFI. UTC-CCS Comments on Rugulatory Burden 07112016 Version 1 2 (333.82 KB) More Documents & Publications ISSUANCE 2016-05-19: Energy Conservation Program: Test Procedures for Central Air Conditioners and Heat Pumps Final Rule 2015-02-13 Issuance:

  3. Intrinsic carrier multiplication efficiency in bulk Si crystals evaluated by optical-pump/terahertz-probe spectroscopy

    SciTech Connect (OSTI)

    Yamashita, G.; Nagai, M. E-mail: ashida@mp.es.osaka-u.ac.jp; Ashida, M. E-mail: ashida@mp.es.osaka-u.ac.jp; Matsubara, E.; Kanemitsu, Y.

    2014-12-08

    We estimated the carrier multiplication efficiency in the most common solar-cell material, Si, by using optical-pump/terahertz-probe spectroscopy. Through close analysis of time-resolved data, we extracted the exact number of photoexcited carriers from the sheet carrier density 10 ps after photoexcitation, excluding the influences of spatial diffusion and surface recombination in the time domain. For incident photon energies greater than 4.0 eV, we observed enhanced internal quantum efficiency due to carrier multiplication. The evaluated value of internal quantum efficiency agrees well with the results of photocurrent measurements. This optical method allows us to estimate the carrier multiplication and surface recombination of carriers quantitatively, which are crucial for the design of the solar cells.

  4. Chemical Energy Carriers (CEC) for the Utilization of Geothermal Energy |

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

    Department of Energy Energy Carriers (CEC) for the Utilization of Geothermal Energy Chemical Energy Carriers (CEC) for the Utilization of Geothermal Energy DOE Geothermal Peer Review 2010 - Presentation. Project objective: Develop chemical energy carrier (CEC) systems to recover thermal energy from enhanced geothermal systems (EGS) in the form of chemical energy, in addition to sensible and latent energy. specialized_jody_chemical_carriers.pdf (489.93 KB) More Documents & Publications

  5. Novel Hydrogen Carriers | Department of Energy

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

    Hydrogen Delivery » Novel Hydrogen Carriers Novel Hydrogen Carriers Hydrogen carriers store hydrogen in some other chemical state rather than as free hydrogen molecules. Additional research and analyses are underway to investigate novel liquid or solid hydrogen carriers for use in delivery. Carriers are a unique way to deliver hydrogen by hydriding a chemical compound at the site of production and then dehydriding it either at the point of delivery or once it is onboard the fuel cell vehicle.

  6. Oxygen Carriers for Solid Fuel Chemical Looping Combustion Process - Energy

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

    Innovation Portal Oxygen Carriers for Solid Fuel Chemical Looping Combustion Process Regenerable Mixed Copper-Iron-Inert Support Oxygen Carriers National Energy Technology Laboratory Contact NETL About This Technology Publications: PDF Document Publication 13159553.pdf (405 KB) Technology Marketing Summary This patent-pending technology, "Regenerable Mixed Copper-Iron-Inert Support Oxygen Carriers for Solid Fuel Chemical Looping Combustion Process," provides a metal-oxide oxygen

  7. Heat to electricity conversion by cold carrier emissive energy harvesters

    SciTech Connect (OSTI)

    Strandberg, Rune

    2015-12-07

    This paper suggests a method to convert heat to electricity by the use of devices called cold carrier emissive energy harvesters (cold carrier EEHs). The working principle of such converters is explained and theoretical power densities and efficiencies are calculated for ideal devices. Cold carrier EEHs are based on the same device structure as hot carrier solar cells, but works in an opposite way. Whereas a hot carrier solar cell receives net radiation from the sun and converts some of this radiative heat flow into electricity, a cold carrier EEH sustains a net outflux of radiation to the surroundings while converting some of the energy supplied to it into electricity. It is shown that the most basic type of cold carrier EEHs have the same theoretical efficiency as the ideal emissive energy harvesters described earlier by Byrnes et al. In the present work, it is also shown that if the emission from the cold carrier EEH originates from electron transitions across an energy gap where a difference in the chemical potential of the electrons above and below the energy gap is sustained, power densities slightly higher than those given by Byrnes et al. can be achieved.

  8. Carrier multiplication detected through transient photocurrent in device-grade films of lead selenide quantum dots

    SciTech Connect (OSTI)

    Gao, Jianbo; Fidler, Andrew F.; Klimov, Victor I.

    2015-09-08

    In carrier multiplication, the absorption of a single photon results in two or more electron–hole pairs. Quantum dots are promising materials for implementing carrier multiplication principles in real-life technologies. So far, however, most of research in this area has focused on optical studies of solution samples with yet to be proven relevance to practical devices. We report ultra-fast electro-optical studies of device-grade films of electronically coupled quantum dots that allow us to observe multiplication directly in the photocurrent. Our studies help rationalize previous results from both optical spectroscopy and steady-state photocurrent measurements and also provide new insights into effects of electric field and ligand treatments on multiexciton yields. Importantly, we demonstrate that using appropriate chemical treatments of the films, extra charges produced by carrier multiplication can be extracted from the quantum dots before they are lost to Auger recombination and hence can contribute to photocurrent of practical devices.

  9. Electric properties and carrier multiplication in breakdown sites in multi-crystalline silicon solar cells

    SciTech Connect (OSTI)

    Schneemann, Matthias; Carius, Reinhard; Rau, Uwe; Kirchartz, Thomas

    2015-05-28

    This paper studies the effective electrical size and carrier multiplication of breakdown sites in multi-crystalline silicon solar cells. The local series resistance limits the current of each breakdown site and is thereby linearizing the current-voltage characteristic. This fact allows the estimation of the effective electrical diameters to be as low as 100 nm. Using a laser beam induced current (LBIC) measurement with a high spatial resolution, we find carrier multiplication factors on the order of 30 (Zener-type breakdown) and 100 (avalanche breakdown) as new lower limits. Hence, we prove that also the so-called Zener-type breakdown is followed by avalanche multiplication. We explain that previous measurements of the carrier multiplication using thermography yield results higher than unity, only if the spatial defect density is high enough, and the illumination intensity is lower than what was used for the LBIC method. The individual series resistances of the breakdown sites limit the current through these breakdown sites. Therefore, the measured multiplication factors depend on the applied voltage as well as on the injected photocurrent. Both dependencies are successfully simulated using a series-resistance-limited diode model.

  10. Carrier Multiplication in Semiconductor Nanocrystals: Theoretical Screening of Candidate Materials Based on Band-Structure Effects

    SciTech Connect (OSTI)

    Luo, J. W.; Franceschetti, A.; Zunger, A.

    2008-01-01

    Direct carrier multiplication (DCM) occurs when a highly excited electron-hole pair decays by transferring its excess energy to the electrons rather than to the lattice, possibly exciting additional electron-hole pairs. Atomistic electronic structure calculations have shown that DCM can be induced by electron-hole Coulomb interactions, in an impact-ionization-like process whose rate is proportional to the density of biexciton states {rho}{sub XX}. Here we introduce a DCM 'figure of merit' R{sub 2}(E) which is proportional to the ratio between the biexciton density of states {rho}{sub XX} and the single-exciton density of states {rho}{sub x}, restricted to single-exciton and biexciton states that are coupled by Coulomb interactions. Using R{sub 2}(E), we consider GaAs, InAs, InP, GaSb, InSb, CdSe, Ge, Si, and PbSe nanocrystals of different sizes. Although DCM can be affected by both quantum-confinement effects (reflecting the underly electronic structure of the confined dot-interior states) and surface effects, here we are interested to isolate the former. To this end the nanocrystal energy levels are obtained from the corresponding bulk band structure via the truncated crystal approximation. We find that PbSe, Si, GaAs, CdSe, and InP nanocrystals have larger DCM figure of merit than the other nanocrystals. Our calculations suggest that high DCM efficiency requires high degeneracy of the corresponding bulk band-edge states. Interestingly, by considering band structure effects we find that as the dot size increases the DCM critical energy E{sub 0} (the energy at which R{sub 2}(E) becomes {ge}1) is reduced, suggesting improved DCM. However, whether the normalized E{sub 0}/{var_epsilon}{sub g} increases or decreases as the dot size increases depends on dot material.

  11. Carrier multiplication detected through transient photocurrent in device-grade films of lead selenide quantum dots

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

    Gao, Jianbo; Fidler, Andrew F.; Klimov, Victor I.

    2015-09-08

    In carrier multiplication, the absorption of a single photon results in two or more electron–hole pairs. Quantum dots are promising materials for implementing carrier multiplication principles in real-life technologies. So far, however, most of research in this area has focused on optical studies of solution samples with yet to be proven relevance to practical devices. We report ultra-fast electro-optical studies of device-grade films of electronically coupled quantum dots that allow us to observe multiplication directly in the photocurrent. Our studies help rationalize previous results from both optical spectroscopy and steady-state photocurrent measurements and also provide new insights into effects ofmore » electric field and ligand treatments on multiexciton yields. Importantly, we demonstrate that using appropriate chemical treatments of the films, extra charges produced by carrier multiplication can be extracted from the quantum dots before they are lost to Auger recombination and hence can contribute to photocurrent of practical devices.« less

  12. Multifunctional Catalysts to Synthesize and Utilize Energy Carriers

    SciTech Connect (OSTI)

    Lercher, Johannes A.; Appel, Aaron M.; Autrey, Thomas; Bullock, R. Morris; Camaioni, Donald M.; Cho, Herman M.; Dixon, David A.; Dohnalek, Zdenek; Gao, Feng; Glezakou, Vassiliki Alexandra; Henderson, Michael A.; Hu, Jian Z.; Iglesia, Enrique; Karkamkar, Abhijeet J.; Kay, Bruce D.; Kimmel, Gregory A.; Linehan, John C.; Liu, Jun; Lyubinetsky, Igor; Mei, Donghai; Peden, Charles HF; Rousseau, Roger J.; Schenter, Gregory K.; Shaw, Wendy J.; Szanyi, Janos; Wang, Huamin; Wang, Yong; Weber, Robert S.

    2014-06-23

    The central role and critical importance of catalysis in a future based on sustainability, together with the insight that developments have to be knowledge-based have motivated significant efforts to better understand catalyzed processes and to develop new catalytic routes from this knowledge. Overall, three main energy carriers are used worldwide, carbon (and hydrocarbons), hydrogen, and electrons. Conventionally, the stored energy is accessed by oxidizing carbon and hydrogen, forming O-H and C-O bonds and performing work with the produced heat or electricity. Conversely, to synthesize energy carriers sustainably, it is consequently required to reverse the direction, i.e., to break C-O and O-H bonds and form C-C, C-H and H-H bonds. To address these challenges, PNNL’s BES-sponsored program comprises three thrust areas with subtasks, focusing on the fundamentals of biomass conversion processes, direct and indirect CO2 reduction, and on elementary studies aimed at generating and using H2. Multi-functionality, i.e., the simultaneous interaction of more than one catalytically active site with the substrate is the key to achieving the atom and energy efficiency in individual steps. The combination of several types of these sites with carefully selected energetics and rate constants is used to generate complex catalysts able to enhance the rates of multistep processes. This short report summarizes recent results obtained in this BES-funded program.

  13. ARS 40 - Public Utilities and Carriers | Open Energy Information

    Open Energy Info (EERE)

    StatuteStatute: ARS 40 - Public Utilities and CarriersLegal Abstract This title sets forth the statutes for public utilities and carriers in Arizona. Published NA Year Signed...

  14. Multiple conducting carriers generated in LaAlO3/SrTiO3 heterostructur...

    Office of Scientific and Technical Information (OSTI)

    the origin of high-mobility transport to the low-density conducting carriers. Authors: Seo, Sung Seok A 1 ; Marton, Zsolt 1 ; Choi, W. S. 2 ; Hassink, G. W. J. 3 ; Blank, ...

  15. Charged-particle multiplicity at LHC energies

    ScienceCinema (OSTI)

    None

    2011-10-06

    The talk presents the measurement of the pseudorapidity density and the multiplicity distribution with ALICE at the achieved LHC energies of 0.9 and 2.36 TeV.An overview about multiplicity measurements prior to LHC is given and the related theoretical concepts are briefly discussed.The analysis procedure is presented and the systematic uncertainties are detailed. The applied acceptance corrections and the treatment of diffraction are discussed.The results are compared with model predictions. The validity of KNO scaling in restricted phase space regions is revisited. 

  16. Plasmonic hot carrier dynamics in solid-state and chemical systems for energy conversion

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

    Narang, Prineha; Sundararaman, Ravishankar; Atwater, Harry A.

    2016-06-11

    Surface plasmons provide a pathway to efficiently absorb and confine light in metallic nanostructures, thereby bridging photonics to the nano scale. The decay of surface plasmons generates energetic ‘hot’ carriers, which can drive chemical reactions or be injected into semiconductors for nano-scale photochemical or photovoltaic energy conversion. Novel plasmonic hot carrier devices and architectures continue to be demonstrated, but the complexity of the underlying processes make a complete microscopic understanding of all the mechanisms and design considerations for such devices extremely challenging.Here,we review the theoretical and computational efforts to understand and model plasmonic hot carrier devices.We split the problem intomore » three steps: hot carrier generation, transport and collection, and review theoretical approaches with the appropriate level of detail for each step along with their predictions. As a result, we identify the key advances necessary to complete the microscopic mechanistic picture and facilitate the design of the next generation of devices and materials for plasmonic energy conversion.« less

  17. Project Profile: CSP Energy Storage Solutions - Multiple Technologies...

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

    Concentrating Solar Power Project Profile: CSP Energy Storage Solutions - Multiple ... construction techniques Development of system operation strategies Maximization of ...

  18. Resonant tunneling diodes as energy-selective contacts used in hot-carrier solar cells

    SciTech Connect (OSTI)

    Takeda, Yasuhiko Sugimoto, Noriaki; Ichiki, Akihisa; Kusano, Yuya; Motohiro, Tomoyoshi

    2015-09-28

    Among the four features unique to hot-carrier solar cells (HC-SCs): (i) carrier thermalization time and (ii) carrier equilibration time in the absorber, (iii) energy-selection width and (iv) conductance of the energy-selective contacts (ESCs), requisites of (i)-(iii) for high conversion efficiency have been clarified. We have tackled the remaining issues related to (iv) in the present study. The detailed balance model of HC-SC operation has been improved to involve a finite value of the ESC conductance to find the required values, which in turn has been revealed to be feasible using resonant tunneling diodes (RTDs) consisting of semiconductor quantum dots (QDs) and quantum wells (QWs) by means of a formulation to calculate the conductance of the QD- and QW-RTDs derived using the rigorous solutions of the effective-mass Hamiltonians. Thus, all of the four requisites unique to HC-SCs to achieve high conversion efficiency have been elucidated, and the two requisites related to the ESCs can be fulfilled using the QD- and QW-RTDs.

  19. Comparison with Carrier Multiplication

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

    Efficiency (QE) Efficiency % with Down-Conversion Single- Junction Threshold Solar Cell 1 2 3 4 5 6 7 8 9 10 20 30 40 50 60 70 80 90 Peak Efficiency % Splitting...

  20. Project Profile: CSP Energy Storage Solutions - Multiple Technologies

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

    Compared | Department of Energy Concentrating Solar Power » Project Profile: CSP Energy Storage Solutions - Multiple Technologies Compared Project Profile: CSP Energy Storage Solutions - Multiple Technologies Compared US Solar Holdings logo US Solar Holdings, under the Thermal Storage FOA, is aiming to demonstrate commercial, utility-scale thermal energy storage technologies and provide a path to cost-effective energy storage for CSP plants >50 MW. Approach US Solar Holdings is

  1. Characterization of Tritium Breeding Ratio and Energy Multiplication...

    Office of Scientific and Technical Information (OSTI)

    Factor of Lithium-based Ternary Alloys in IFE Blankets Citation Details In-Document Search Title: Characterization of Tritium Breeding Ratio and Energy Multiplication Factor of ...

  2. AltaRock Energy Announces Successful Multiple-Zone Stimulation...

    Energy Savers [EERE]

    Geothermal Systems Demonstration AltaRock Energy Announces Successful Multiple-Zone Stimulation of Well at the Newberry Enhanced Geothermal Systems Demonstration January 22, 2013 - ...

  3. Effect of number of stack on the thermal escape and non-radiative and radiative recombinations of photoexcited carriers in strain-balanced InGaAs/GaAsP multiple quantum-well-inserted solar cells

    SciTech Connect (OSTI)

    Aihara, Taketo; Fukuyama, Atsuhiko; Ikari, Tetsuo; Suzuki, Hidetoshi; Fujii, Hiromasa; Nakano, Yoshiaki; Sugiyama, Masakazu

    2015-02-28

    Three non-destructive methodologies, namely, surface photovoltage (SPV), photoluminescence, and piezoelectric photothermal (PPT) spectroscopies, were adopted to detect the thermal carrier escape from quantum well (QW) and radiative and non-radiative carrier recombinations, respectively, in strain-balanced InGaAs/GaAsP multiple-quantum-well (MQW)-inserted GaAs p-i-n solar cell structure samples. Although the optical absorbance signal intensity was proportional to the number of QW stack, the signal intensities of the SPV and PPT methods decreased at high number of stack. To explain the temperature dependency of these signal intensities, we proposed a model that considers the three carrier dynamics: the thermal escape from the QW, and the non-radiative and radiative carrier recombinations within the QW. From the fitting procedures, it was estimated that the activation energies of the thermal escape ΔE{sub barr} and non-radiative recombination ΔE{sub NR} were 68 and 29 meV, respectively, for a 30-stacked MQW sample. The estimated ΔE{sub barr} value agreed well with the difference between the first electron subband and the top of the potential barrier in the conduction band. We found that ΔE{sub barr} remained constant at approximately 70 meV even with increasing QW stack number. However, the ΔE{sub NR} value monotonically increased with the increase in the number of stack. Since this implies that non-radiative recombination becomes improbable as the number of stack increases, we found that the radiative recombination probability for electrons photoexcited within the QW increased at a large number of QW stack. Additional processes of escaping and recapturing of carriers at neighboring QW were discussed. As a result, the combination of the three non-destructive methodologies provided us new insights for optimizing the MQW components to further improve the cell performance.

  4. Refrigerator-Freezers (multiple defrost waiver) | Department of Energy

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

    Refrigerator-Freezers (multiple defrost waiver) Refrigerator-Freezers (multiple defrost waiver) The Department of Energy (DOE) develops standardized data templates for reporting the results of tests conducted in accordance with current DOE test procedures. Templates may be used by third-party laboratories under contract with DOE that conduct testing in support of ENERGY STAR® verification, DOE rulemakings, and enforcement of the federal energy conservation standards. Residential

  5. Multiple Motivations Institutional Change Principle | Department of Energy

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

    Institutional Change » Multiple Motivations Institutional Change Principle Multiple Motivations Institutional Change Principle The multiple motivations principle suggests that a portfolio approach-rather than a single strategy-may be required to achieve change. Research demonstrates that people and institutions adopt new behaviors for many reasons. They likely need more than one reason for changing their current behavior. Therefore, people may shift to more sustainable, energy-efficient

  6. Binding energies and spatial structures of small carrier complexes in monolayer transition-metal dichalcogenides via diffusion Monte Carlo

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

    Mayers, Matthew Z.; Berkelbach, Timothy C.; Hybertsen, Mark S.; Reichman, David R.

    2015-10-09

    Ground-state diffusion Monte Carlo is used to investigate the binding energies and intercarrier radial probability distributions of excitons, trions, and biexcitons in a variety of two-dimensional transition-metal dichalcogenide materials. We compare these results to approximate variational calculations, as well as to analogous Monte Carlo calculations performed with simplified carrier interaction potentials. Our results highlight the successes and failures of approximate approaches as well as the physical features that determine the stability of small carrier complexes in monolayer transition-metal dichalcogenide materials. In conclusion, we discuss points of agreement and disagreement with recent experiments.

  7. Structuring Materials on Multiple Length Scales for Energy Applications |

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

    MIT-Harvard Center for Excitonics Structuring Materials on Multiple Length Scales for Energy Applications October 25, 2012 at 3pm/36-428 Adreas Stein Department of Chemistry, University of Minnesota astein Abstract: Nanoporous and nanostructured materials are becoming increasingly important for advanced applications, including energy storage and conversion materials. Templating methods based on hard templates (colloidal crystal templating, nanocasting) and soft templates (surfactant systems)

  8. High Efficiency Multiple-Junction Solar Cells - Energy Innovation Portal

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

    Solar Photovoltaic Solar Photovoltaic Find More Like This Return to Search High Efficiency Multiple-Junction Solar Cells Sandia National Laboratories Contact SNL About This Technology Publications: PDF Document Publication Market Sheet (937 KB) Technology Marketing SummarySingle junction solar cells have limited efficiency and fail to extract maximum energy from photons outside of a specific spectral region. Higher efficiency and optical to electrical energy conversion is achieved by stacking

  9. Los Alamos Lab: Science Program Office, Energy Security Newsletter

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

    Fossil Energy & Environment Home Office of Science Home ... of a New Era for Solar Energy Carrier multiplication and quantum dots can double the efficiency of photovoltaic panels. ...

  10. Optimal Power Flow of Multiple Energy Carriers(Geidl and Andersson...

    Open Energy Info (EERE)

    topics related to ESI Posted: 15 Nov 2012 - 13:55 by Qinsun Qinsun Prospects for Nuclear Power(Davis 2012) Posted: 15 Nov 2012 - 13:36 by Qinsun 1 of 4 Groups Menu You...

  11. Multiple-energy Techniques in Industrial Computerized Tomography

    DOE R&D Accomplishments [OSTI]

    Schneberk, D.; Martz, H.; Azevedo, S.

    1990-08-01

    Considerable effort is being applied to develop multiple-energy industrial CT techniques for materials characterization. Multiple-energy CT can provide reliable estimates of effective Z (Z{sub eff}), weight fraction, and rigorous calculations of absolute density, all at the spatial resolution of the scanner. Currently, a wide variety of techniques exist for CT scanners, but each has certain problems and limitations. Ultimately, the best multi-energy CT technique would combine the qualities of accuracy, reliability, and wide range of application, and would require the smallest number of additional measurements. We have developed techniques for calculating material properties of industrial objects that differ somewhat from currently used methods. In this paper, we present our methods for calculating Z{sub eff}, weight fraction, and density. We begin with the simplest case -- methods for multiple-energy CT using isotopic sources -- and proceed to multiple-energy work with x-ray machine sources. The methods discussed here are illustrated on CT scans of PBX-9502 high explosives, a lexan-aluminum phantom, and a cylinder of glass beads used in a preliminary study to determine if CT can resolve three phases: air, water, and a high-Z oil. In the CT project at LLNL, we have constructed several CT scanners of varying scanning geometries using {gamma}- and x-ray sources. In our research, we employed two of these scanners: pencil-beam CAT for CT data using isotopic sources and video-CAT equipped with an IRT micro-focal x-ray machine source.

  12. Communication: Separable potential energy surfaces from multiplicative artificial neural networks

    SciTech Connect (OSTI)

    Koch, Werner, E-mail: wkoch@thethirdrock.net; Zhang, Dong H. [State Key Laboratory of Molecular Reaction Dynamics and Center for Theoretical Computational Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian (China)

    2014-07-14

    We present a potential energy surface fitting scheme based on multiplicative artificial neural networks. It has the sum of products form required for efficient computation of the dynamics of multidimensional quantum systems with the multi configuration time dependent Hartree method. Moreover, it results in analytic potential energy matrix elements when combined with quantum dynamics methods using Gaussian basis functions, eliminating the need for a local harmonic approximation. Scaling behavior with respect to the complexity of the potential as well as the requested accuracy is discussed.

  13. Smart Energy Management of Multiple Full Cell Powered Applications

    SciTech Connect (OSTI)

    Mohammad S. Alam

    2007-04-23

    In this research project the University of South Alabama research team has been investigating smart energy management and control of multiple fuel cell power sources when subjected to varying demands of electrical and thermal loads together with demands of hydrogen production. This research has focused on finding the optimal schedule of the multiple fuel cell power plants in terms of electric, thermal and hydrogen energy. The optimal schedule is expected to yield the lowest operating cost. Our team is also investigating the possibility of generating hydrogen using photoelectrochemical (PEC) solar cells through finding materials for efficient light harvesting photoanodes. The goal is to develop an efficient and cost effective PEC solar cell system for direct electrolysis of water. In addition, models for hydrogen production, purification, and storage will be developed. The results obtained and the data collected will be then used to develop a smart energy management algorithm whose function is to maximize energy conservation within a managed set of appliances, thereby lowering O/M costs of the Fuel Cell power plant (FCPP), and allowing more hydrogen generation opportunities. The Smart Energy Management and Control (SEMaC) software, developed earlier, controls electrical loads in an individual home to achieve load management objectives such that the total power consumption of a typical residential home remains below the available power generated from a fuel cell. In this project, the research team will leverage the SEMaC algorithm developed earlier to create a neighborhood level control system.

  14. Research Challenge 4: Defect-Carrier Interactions

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

    4: Defect-Carrier Interactions - Sandia Energy Energy Search Icon Sandia Home Locations Contact Us Employee Locator Energy & Climate Secure & Sustainable Energy Future Stationary ...

  15. Algorithm for Accounting for the Interactions of Multiple Renewable Energy Technologies in Estimation of Annual Performance

    Energy Science and Technology Software Center (OSTI)

    2007-12-31

    The algorithm accounts for interactions between technologies in determining the annual energy performance of multiple renewable energy technologies at a subject site.

  16. AltaRock Energy Announces Successful Multiple-Zone Stimulation of Well at

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

    the Newberry Enhanced Geothermal Systems Demonstration | Department of Energy AltaRock Energy Announces Successful Multiple-Zone Stimulation of Well at the Newberry Enhanced Geothermal Systems Demonstration AltaRock Energy Announces Successful Multiple-Zone Stimulation of Well at the Newberry Enhanced Geothermal Systems Demonstration January 22, 2013 - 3:41pm Addthis SEATTLE -- AltaRock Energy today announced that it has created multiple stimulated zones from a single wellbore at the

  17. U-035: Adobe Flash Player Multiple Vulnerabilities | Department of Energy

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

    35: Adobe Flash Player Multiple Vulnerabilities U-035: Adobe Flash Player Multiple Vulnerabilities November 14, 2011 - 10:15am Addthis PROBLEM: Adobe Flash Player Multiple Vulnerabilities. PLATFORM: Adobe Flash Player 11.0.1.152 and earlier versions for Windows, Macintosh, Linux and Solaris operating systems Adobe Flash Player 11.0.1.153 and earlier versions for Android Adobe AIR 3.0 and earlier versions for Windows, Macintosh, and Android ABSTRACT: Adobe recommends users of Adobe Flash Player

  18. U-198: IBM Lotus Expeditor Multiple Vulnerabilities | Department of Energy

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

    8: IBM Lotus Expeditor Multiple Vulnerabilities U-198: IBM Lotus Expeditor Multiple Vulnerabilities June 25, 2012 - 7:00am Addthis PROBLEM: Multiple vulnerabilities have been reported in IBM Lotus Expeditor. PLATFORM: IBM Lotus Expeditor 6.x ABSTRACT: The vulnerabilities can be exploited by malicious people to conduct cross-site scripting attacks, disclose potentially sensitive information, bypass certain security restrictions, and compromise a user's system.. Reference Links: Vendor Advisory

  19. U-162: Drupal Multiple Vulnerabilities | Department of Energy

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

    2: Drupal Multiple Vulnerabilities U-162: Drupal Multiple Vulnerabilities May 4, 2012 - 7:00am Addthis PROBLEM: Drupal Multiple Vulnerabilities PLATFORM: The vulnerabilities are reported in 7.x versions prior to 7.13. ABSTRACT: Several vulnerabilities were reported in Drupal: Denial of Service, Access bypass, and Unvalidated form redirect reference LINKS: Security Advisory: DRUPAL-SA-CORE-2012-002 Bugtraq ID: 53359 Secunia Advisory SA49012 CVE-2012-1588 CVE-2012-1589 CVE-2012-1590 CVE-2012-1591

  20. U-191: Oracle Java Multiple Vulnerabilities | Department of Energy

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

    1: Oracle Java Multiple Vulnerabilities U-191: Oracle Java Multiple Vulnerabilities June 14, 2012 - 7:00am Addthis PROBLEM: Multiple vulnerabilities have been reported in Oracle Java, which can be exploited by malicious local users PLATFORM: Oracle Java JDK 1.7.x / 7.x Oracle Java JRE 1.7.x / 7.x Sun Java JDK 1.5.x Sun Java JDK 1.6.x / 6.x Sun Java JRE 1.4.x Sun Java JRE 1.5.x / 5.x Sun Java JRE 1.6.x / 6.x Sun Java SDK 1.4.x ABSTRACT: The Critical Patch Update for Java SE also includes

  1. Multiple Layer Graphene Optical Modulator - Energy Innovation Portal

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

    Advanced Materials Advanced Materials Find More Like This Return to Search Multiple Layer Graphene Optical Modulator Lawrence Berkeley National Laboratory Contact LBL About This Technology Publications: PDF Document Publication LBNL Commercial Analysis Report (233 KB) Technology Marketing Summary Scientists at Berkeley Lab have developed a tiny optical modulator based on graphene, potentially leading to significantly improved data transmission speeds in digital communications. The extremely

  2. Integrated Inverter Control for Multiple Electric Machines - Energy

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

    Innovation Portal Industrial Technologies Industrial Technologies Find More Like This Return to Search Integrated Inverter Control for Multiple Electric Machines Oak Ridge National Laboratory Contact ORNL About This Technology Technology Marketing SummaryConventional electric or hybrid electric vehicles have a main motor and one or more accessory motors or generators, plus an inverter for each. A consequence of this design is that each vehicle requires a number of inverters and inverter

  3. Simulation of energy absorption spectrum in NaI crystal detector for multiple gamma energy using Monte Carlo method

    SciTech Connect (OSTI)

    Wirawan, Rahadi; Waris, Abdul; Djamal, Mitra; Handayani, Gunawan

    2015-04-16

    The spectrum of gamma energy absorption in the NaI crystal (scintillation detector) is the interaction result of gamma photon with NaI crystal, and it’s associated with the photon gamma energy incoming to the detector. Through a simulation approach, we can perform an early observation of gamma energy absorption spectrum in a scintillator crystal detector (NaI) before the experiment conducted. In this paper, we present a simulation model result of gamma energy absorption spectrum for energy 100-700 keV (i.e. 297 keV, 400 keV and 662 keV). This simulation developed based on the concept of photon beam point source distribution and photon cross section interaction with the Monte Carlo method. Our computational code has been successfully predicting the multiple energy peaks absorption spectrum, which derived from multiple photon energy sources.

  4. Solid state cloaking for electrical charge carrier mobility control

    SciTech Connect (OSTI)

    Zebarjadi, Mona; Liao, Bolin; Esfarjani, Keivan; Chen, Gang

    2015-07-07

    An electrical mobility-controlled material includes a solid state host material having a controllable Fermi energy level and electrical charge carriers with a charge carrier mobility. At least one Fermi level energy at which a peak in charge carrier mobility is to occur is prespecified for the host material. A plurality of particles are distributed in the host material, with at least one particle disposed with an effective mass and a radius that minimize scattering of the electrical charge carriers for the at least one prespecified Fermi level energy of peak charge carrier mobility. The minimized scattering of electrical charge carriers produces the peak charge carrier mobility only at the at least one prespecified Fermi level energy, set by the particle effective mass and radius, the charge carrier mobility being less than the peak charge carrier mobility at Fermi level energies other than the at least one prespecified Fermi level energy.

  5. Ultrafast carriers dynamics in filled-skutterudites

    SciTech Connect (OSTI)

    Guo, Liang; Xu, Xianfan; Salvador, James R.

    2015-06-08

    Carrier dynamics of filled-skutterudites, an important class of thermoelectric materials, is investigated using ultrafast optical spectroscopy. By tuning the wavelength of the probe laser, charge transfers at different electronic energy levels are interrogated. Analysis based on the Kramers-Kronig relation explains the complex spectroscopy data, which is mainly due to band filling caused by photo-excited carriers and free carrier absorption. The relaxation time of hot carriers is found to be about 0.4–0.6 ps, depending on the electronic energy level, and the characteristic time for carrier-phonon equilibrium is about 0.95 ps. These studies of carrier dynamics, which fundamentally determines the transport properties of thermoelectric material, can provide guidance for the design of materials.

  6. Potential Carriers and Approaches for Hydrogen Delivery

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

    Carriers and Potential Carriers and Approaches for Hydrogen Approaches for Hydrogen Delivery Delivery TIAX LLC 1601 S. D Anza Blvd. Cupertino CA, 95014 Tel. 408-517-1550 Reference: D0348 © 2007 TIAX LLC Hydrogen Delivery Analysis Meeting May 8-9, 2007 Columbia, Maryland Matthew Hooks Stefan Unnasch Stephen Lasher 1 Novel Hydrogen Carriers Project Overview Cost Density (wt. and vol.) Energy requirements Forecourt storage requirements Codes and standards H H 2 2 Plant, Liquefier, LH Plant,

  7. Research Challenge 4: Defect-Carrier Interactions

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

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

  8. An Energy Storage Assessment: Using Optimal Control Strategies to Capture Multiple Services

    SciTech Connect (OSTI)

    Wu, Di; Jin, Chunlian; Balducci, Patrick J.; Kintner-Meyer, Michael CW

    2015-09-01

    This paper presents a methodology for evaluating benefits of battery storage for multiple grid applications, including energy arbitrage, balancing service, capacity value, distribution system equipment deferral, and outage mitigation. In the proposed method, at each hour, a look-ahead optimization is first formulated and solved to determine battery base operating point. The minute by minute simulation is then performed to simulate the actual battery operation. This methodology is used to assess energy storage alternatives in Puget Sound Energy System. Different battery storage candidates are simulated for a period of one year to assess different value streams and overall benefits, as part of a financial feasibility evaluation of battery storage projects.

  9. Part-load performance characterization and energy savings potential of the RTU challenge unit: Carrier weather expert

    SciTech Connect (OSTI)

    Wang, Weimin; Katipamula, Srinivas; Taasevigen, Danny J.

    2015-09-29

    This report documents the development of part-load performance curves and there use with the EnergyPlus simulation tool to estimate the potential savings from the use of WeatherExpert units compared to other standard options.

  10. 14.12.16 RH Hot Carrier - JCAP

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

    Hot-Carrier Generation from Plasmon Decay in Energy Conversion Sundararaman , R., Narang, P., Jermyn, A. S., Goddard, W. A. & Atwater, H. A. Theoretical predictions for hot-carrier ...

  11. Energy dependence of the ridge in high multiplicity proton-proton collisions

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

    Dusling, Kevin; Tribedy, Prithwish; Venugopalan, Raju

    2016-01-27

    In this study, we demonstrate that the recent measurement of azimuthally collimated, long-range rapidity (“ridge”) correlations in √s=13 TeV proton-proton (p+p) collisions by the ATLAS Collaboration at the LHC are in agreement with expectations from the color glass condensate effective theory of high-energy QCD. The observation that the integrated near-side yield as a function of multiplicity is independent of collision energy is a natural consequence of the fact that multiparticle production is driven by a single semihard saturation scale in the color glass condensate framework. We argue further that the azimuthal structure of these recent ATLAS ridge measurements strongly constrainsmore » hydrodynamic interpretations of such correlations in high-multiplicity p+p collisions.« less

  12. Injection current dependences of electroluminescence transition energy in InGaN/GaN multiple quantum wells light emitting diodes under pulsed current conditions

    SciTech Connect (OSTI)

    Zhang, Feng; Ikeda, Masao Liu, Jianping; Zhang, Shuming; Zhou, Kun; Yang, Hui; Liu, Zongshun

    2015-07-21

    Injection current dependences of electroluminescence transition energy in blue InGaN/GaN multiple quantum wells light emitting diodes (LEDs) with different quantum barrier thicknesses under pulsed current conditions have been analyzed taking into account the related effects including deformation caused by lattice strain, quantum confined Stark effects due to polarization field partly screened by carriers, band gap renormalization, Stokes-like shift due to compositional fluctuations which are supposed to be random alloy fluctuations in the sub-nanometer scale, band filling effect (Burstein-Moss shift), and quantum levels in finite triangular wells. The bandgap renormalization and band filling effect occurring at high concentrations oppose one another, however, the renormalization effect dominates in the concentration range studied, since the band filling effect arising from the filling in the tail states in the valence band of quantum wells is much smaller than the case in the bulk materials. In order to correlate the carrier densities with current densities, the nonradiative recombination rates were deduced experimentally by curve-fitting to the external quantum efficiencies. The transition energies in LEDs both with 15 nm quantum barriers and 5 nm quantum barriers, calculated using full strengths of theoretical macroscopic polarization given by Barnardini and Fiorentini [Phys. Status Solidi B 216, 391 (1999)] are in excellent accordance with experimental results. The LED with 5 nm barriers has been shown to exhibit a higher transition energy and a smaller blue shift than those of LED with 15 nm barriers, which is mainly caused by the smaller internal polarization field in the quantum wells.

  13. Characterizing multiple solutions to the time-energy canonical commutation relation via internal symmetries

    SciTech Connect (OSTI)

    Caballar, Roland Cristopher F.; Ocampo, Leonard R.; Galapon, Eric A.

    2010-06-15

    Internal symmetries can be used to classify multiple solutions to the time-energy canonical commutation relation (TE-CCR). The dynamical behavior of solutions to the TE-CCR possessing particular internal symmetries involving time reversal differ significantly from solutions to the TE-CCR without those particular symmetries, implying a connection between the internal symmetries of a quantum system, its internal unitary dynamics, and the TE-CCR.

  14. Technical Assessment of Organic Liquid Carrier Hydrogen Storage...

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

    Technical Assessment of Organic Liquid Carrier Hydrogen Storage Systems for Automotive Applications Technical report describing the U.S. Department of Energy's (DOE) assessment of ...

  15. Carrier Corporation 7310 West Morris Street

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

    Carrier Corporation 7310 West Morris Street Indianapolis, IN. 46231 July 11, 2016 U.S. Department of Energy Office of General Counsel 1000 Independence Avenue SW. Room 6A245 Washington, DC, 20585 RE: Comments to Docket Number: 2016-10956 Regulatory Burden RFI United Technologies Climate, Controls, and Security and its Carrier business would like to submit the following comments to the proposed questions as well as additional commentary as requested and referenced in the RFI. As referenced in the

  16. Extracting hot carriers from photoexcited semiconductor nanocrystals

    SciTech Connect (OSTI)

    Zhu, Xiaoyang

    2014-12-10

    This research program addresses a fundamental question related to the use of nanomaterials in solar energy -- namely, whether semiconductor nanocrystals (NCs) can help surpass the efficiency limits, the so-called “Shockley-Queisser” limit, in conventional solar cells. In these cells, absorption of photons with energies above the semiconductor bandgap generates “hot” charge carriers that quickly “cool” to the band edges before they can be utilized to do work; this sets the solar cell efficiency at a limit of ~31%. If instead, all of the energy of the hot carriers could be captured, solar-to-electric power conversion efficiencies could be increased, theoretically, to as high as 66%. A potential route to capture this energy is to utilize semiconductor nanocrystals. In these materials, the quasi-continuous conduction and valence bands of the bulk semiconductor become discretized due to confinement of the charge carriers. Consequently, the energy spacing between the electronic levels can be much larger than the highest phonon frequency of the lattice, creating a “phonon bottleneck” wherein hot-carrier relaxation is possible via slower multiphonon emission. For example, hot-electron lifetimes as long as ~1 ns have been observed in NCs grown by molecular beam epitaxy. In colloidal NCs, long lifetimes have been demonstrated through careful design of the nanocrystal interfaces. Due to their ability to slow electronic relaxation, semiconductor NCs can in principle enable extraction of hot carriers before they cool to the band edges, leading to more efficient solar cells.

  17. 14.12.16 RH Hot Carrier - JCAP

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

    Hot-Carrier Generation from Plasmon Decay in Energy Conversion Sundararaman , R., Narang, P., Jermyn, A. S., Goddard, W. A. & Atwater, H. A. Theoretical predictions for hot-carrier generation from surface plasmo decay. Nature Communications 5, 8, DOI: 10.1038/ncomms6788 (2014). Scientific Achievement First theoretical study combining plasmon modes with density functional theory to predict initial energy distribution of hot carriers in real metals. Significance & impact Understanding the

  18. On Deployment of Multiple Base Stations for Energy-Efficient Communication in Wireless Sensor Networks

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

    Lin, Yunyue; Wu, Qishi; Cai, Xiaoshan; Du, Xiaojiang; Kwon, Ki-Hyeon

    2010-01-01

    Data transmission from sensor nodes to a base station or a sink node often incurs significant energy consumption, which critically affects network lifetime. We generalize and solve the problem of deploying multiple base stations to maximize network lifetime in terms of two different metrics under one-hop and multihop communication models. In the one-hop communication model, the sensors far away from base stations always deplete their energy much faster than others. We propose an optimal solution and a heuristic approach based on the minimal enclosing circle algorithm to deploy a base station at the geometric center of each cluster. In themore » multihop communication model, both base station location and data routing mechanism need to be considered in maximizing network lifetime. We propose an iterative algorithm based on rigorous mathematical derivations and use linear programming to compute the optimal routing paths for data transmission. Simulation results show the distinguished performance of the proposed deployment algorithms in maximizing network lifetime.« less

  19. U-042: Mac RealPlayer Multiple Vulnerabilities | Department of Energy

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

    42: Mac RealPlayer Multiple Vulnerabilities U-042: Mac RealPlayer Multiple Vulnerabilities November 21, 2011 - 9:15am Addthis PROBLEM: Mac RealPlayer Multiple Vulnerabilities. PLATFORM: Versions 12.0.0.1701 and prior. ABSTRACT: Multiple vulnerabilities have been reported in Mac RealPlayer, which can be exploited by malicious people to compromise a user's system. reference LINKS: Secunia Advisory: SA46963 Secunia Vulnerability Report: Mac RealPlayer 12.x Secunia Advisory: SA46954 IMPACT

  20. Comparing Multiple Exciton Generation in Quantum Dots To Impact Ionization in Bulk Semiconductors: Implications for Enhancement of Solar Energy Conversion

    SciTech Connect (OSTI)

    Beard, Matthew C.; Midgett, Aaron G.; Hanna, Mark C.; Luther, Joseph M.; Hughes, Barbara K.; Nozik, Arthur J.

    2010-07-26

    Multiple exciton generation (MEG) in quantum dots (QDs) and impact ionization (II) in bulk semiconductors are processes that describe producing more than one electron-hole pair per absorbed photon. We derive expressions for the proper way to compare MEG in QDs with II in bulk semiconductors and argue that there are important differences in the photophysics between bulk semiconductors and QDs. Our analysis demonstrates that the fundamental unit of energy required to produce each electron-hole pair in a given QD is the band gap energy. We find that the efficiency of the multiplication process increases by at least 2 in PbSe QDs compared to bulk PbSe, while the competition between cooling and multiplication favors multiplication by a factor of 3 in QDs. We also demonstrate that power conversion efficiencies in QD solar cells exhibiting MEG can greatly exceed conversion efficiencies of their bulk counterparts, especially if the MEG threshold energy can be reduced toward twice the QD band gap energy, which requires a further increase in the MEG efficiency. Finally, we discuss the research challenges associated with achieving the maximum benefit of MEG in solar energy conversion since we show the threshold and efficiency are mathematically related.

  1. Carrier heating and negative photoconductivity in graphene

    SciTech Connect (OSTI)

    Heyman, J. N.; Stein, J. D.; Kaminski, Z. S.; Banman, A. R.; Massari, A. M.; Robinson, J. T.

    2015-01-07

    We investigated negative photoconductivity in graphene using ultrafast terahertz techniques. Infrared transmission was used to determine the Fermi energy, carrier density, and mobility of p-type chemical vapor deposition graphene samples. Time-resolved terahertz photoconductivity measurements using a tunable mid-infrared pump probed these samples at photon energies between 0.35 eV and 1.55 eV, approximately one-half to three times the Fermi energy of the samples. Although interband optical transitions in graphene are blocked for pump photon energies less than twice the Fermi energy, we observe negative photoconductivity at all pump photon energies investigated, indicating that interband excitation is not required to observe this effect. Our results are consistent with a thermalized free-carrier population that cools by electron-phonon scattering, but are inconsistent with models of negative photoconductivity based on population inversion.

  2. Potential Carriers and Approaches for Hydrogen Delivery | Department of

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

    Energy Carriers and Approaches for Hydrogen Delivery Potential Carriers and Approaches for Hydrogen Delivery Presentation by Matthew Hooks of TIAX at the Joint Meeting on Hydrogen Delivery Modeling and Analysis, May 8-9, 2007 deliv_analysis_hooks_carriers.pdf (254.09 KB) More Documents & Publications Summary of On-Board Storage Models and Analyses Analyses of Hydrogen Storage Materials and On-Board Systems Hydrogen Storage Systems Anlaysis Working Group Meeting, December 12, 2006

  3. Sealed substrate carrier for electroplating

    DOE Patents [OSTI]

    Ganti, Kalyana Bhargava

    2012-07-17

    One embodiment relates to a substrate carrier for use in electroplating a plurality of substrates. The substrate carrier includes a non-conductive carrier body on which the substrates are held, and conductive lines are embedded within the carrier body. A conductive bus bar is embedded into a top side of the carrier body and is conductively coupled to the conductive lines. A thermoplastic overmold covers a portion of the bus bar, and there is a plastic-to-plastic bond between the thermoplastic overmold and the non-conductive carrier body. Other embodiments, aspects and features are also disclosed.

  4. U-146: Adobe Reader/Acrobat Multiple Vulnerabilities | Department of Energy

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

    6: Adobe Reader/Acrobat Multiple Vulnerabilities U-146: Adobe Reader/Acrobat Multiple Vulnerabilities April 12, 2012 - 8:30am Addthis PROBLEM: Multiple vulnerabilities have been reported in Adobe Reader and Adobe Acrobat. PLATFORM: Adobe Acrobat 9.x Adobe Acrobat X 10.x Adobe Reader 9.x Adobe Reader X 10.x ABSTRACT: Vulnerabilities can be exploited by malicious people to conduct cross-site scripting attacks, bypass certain security restrictions, gain knowledge of potentially sensitive

  5. V-211: IBM iNotes Multiple Vulnerabilities | Department of Energy

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

    1: IBM iNotes Multiple Vulnerabilities V-211: IBM iNotes Multiple Vulnerabilities August 5, 2013 - 6:00am Addthis PROBLEM: Multiple vulnerabilities have been reported in IBM Lotus iNotes PLATFORM: IBM iNotes 9.x ABSTRACT: IBM iNotes has two cross-site scripting vulnerabilities and an ActiveX Integer overflow vulnerability REFERENCE LINKS: Secunia Advisory SA54436 IBM Security Bulletin 1645503 CVE-2013-3027 CVE-2013-3032 CVE-2013-3990 IMPACT ASSESSMENT: High DISCUSSION: 1) Certain input related

  6. Energy dependence of multiplicity fluctuations in heavy ion collisions at 20A to 158A GeV

    SciTech Connect (OSTI)

    Alt, C.; Blume, C.; Bramm, R.; Dinkelaker, P.; Flierl, D.; Kliemant, M.; Kniege, S.; Lungwitz, B.; Mitrovski, M.; Renfordt, R.; Schuster, T.; Stock, R.; Strabel, C.; Stroebele, H.; Utvic, M.; Wetzler, A.; Anticic, T.; Kadija, K.; Nicolic, V.; Susa, T.

    2008-09-15

    Multiplicity fluctuations of positively, negatively, and all charged hadrons in the forward hemisphere were studied in central Pb+Pb collisions at 20A,30A,40A,80A, and 158A GeV. The multiplicity distributions and their scaled variances {omega} are presented as functions of their dependence on collision energy as well as on rapidity and transverse momentum. The distributions have bell-like shapes and their scaled variances are in the range from 0.8 to 1.2 without any significant structure in their energy dependence. No indication of the critical point in fluctuations are observed. The string-hadronic ultrarelativistic quantum molecular dynamics (UrQMD) model significantly overpredicts the mean, but it approximately reproduces the scaled variance of the multiplicity distributions. The predictions of the statistical hadron-resonance gas model obtained within the grand-canonical and canonical ensembles disagree with the measured scaled variances. The narrower than Poissonian multiplicity fluctuations measured in numerous cases may be explained by the impact of conservation laws on fluctuations in relativistic systems.

  7. Maintainable substrate carrier for electroplating

    DOE Patents [OSTI]

    Chen, Chen-An; Abas, Emmanuel Chua; Divino, Edmundo Anida; Ermita, Jake Randal G.; Capulong, Jose Francisco S.; Castillo, Arnold Villamor; Ma; Diana Xiaobing

    2012-07-17

    One embodiment relates to a substrate carrier for use in electroplating a plurality of substrates. The carrier includes a non-conductive carrier body on which the substrates are placed and conductive lines embedded within the carrier body. A plurality of conductive clip attachment parts are attached in a permanent manner to the conductive lines embedded within the carrier body. A plurality of contact clips are attached in a removable manner to the clip attachment parts. The contact clips hold the substrates in place and conductively connecting the substrates with the conductive lines. Other embodiments, aspects and features are also disclosed.

  8. Systematics of the mean energy and the mean multiplicity of prompt neutrons originating from {sup 232}Th fission

    SciTech Connect (OSTI)

    Svirin, M. I.

    2012-12-15

    The cross section for the neutron-induced fission of {sup 232}Th target nuclei, {sigma}{sub f} (E{sub n}), was described within statistical theory. The spectra of the mean multiplicity, v-bar (E{sub n}), and the mean energy, E-bar(E{sub n}), of secondary neutrons accompanying {sup 232}Th fission induced by neutrons of energy extending up to E{sub n} = 20 MeV were analyzed on the basis of the chance structure of the cross section.

  9. Muon Energy Reconstruction Through the Multiple Scattering Method in the NO$\\mathrm{\

    SciTech Connect (OSTI)

    Psihas Olmedo, Silvia Fernanda

    2015-01-01

    Neutrino energy measurements are a crucial component in the experimental study of neutrino oscillations. These measurements are done through the reconstruction of neutrino interactions and energy measurements of their products. This thesis presents the development of a technique to reconstruct the energy of muons from neutrino interactions in the NO$\\mathrm{\

  10. John Papanikolas: Visualizing Charge Carrier Motion in Nanowires...

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

    The SSPP method has been used to directly observe carrier diffusion in Si nanowires and ... Since 2009 he has served as Deputy Director of the UNC Energy Frontier Research Center. ...

  11. Technical Assessment of Organic Liquid Carrier Hydrogen Storage Systems for

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

    Automotive Applications | Department of Energy Assessment of Organic Liquid Carrier Hydrogen Storage Systems for Automotive Applications Technical Assessment of Organic Liquid Carrier Hydrogen Storage Systems for Automotive Applications Technical report describing the U.S. Department of Energy's (DOE) assessment of the performance and cost of organic liquid based hydrogen storage systems for automotive applications. The on-board system performance (by Argonne National Lab) and high-volume

  12. File:BOEMRE atlantic.OCS.multiple.use.map.2003.pdf | Open Energy...

    Open Energy Info (EERE)

    Energy Management, Regulation and Enforcement (BOEMRE) Related Technologies Offshore wind Creation Date 2003-10 Extent Northeast coast of US Countries United States UN Region...

  13. Energy propagation by transverse waves in multiple flux tube systems using filling factors

    SciTech Connect (OSTI)

    Van Doorsselaere, T.; Gijsen, S. E.; Andries, J.; Verth, G. E-mail: stief.gijsen@wis.kuleuven.be E-mail: g.verth@sheffield.ac.uk

    2014-11-01

    In the last few years, it has been found that transverse waves are present at all times in coronal loops or spicules. Their energy has been estimated with an expression derived for bulk Alfvn waves in homogeneous media, with correspondingly uniform wave energy density and flux. The kink mode, however, is localized in space with the energy density and flux dependent on the position in the cross-sectional plane. The more relevant quantities for the kink mode are the integrals of the energy density and flux over the cross-sectional plane. The present paper provides an approximation to the energy propagated by kink modes in an ensemble of flux tubes by means of combining the analysis of single flux tube kink oscillations with a filling factor for the tube cross-sectional area. This finally allows one to compare the expressions for energy flux of Alfvn waves with an ensemble of kink waves. We find that the correction factor for the energy in kink waves, compared to the bulk Alfvn waves, is between f and 2f, where f is the density filling factor of the ensemble of flux tubes.

  14. Public views on multiple dimensions of security : nuclear waepons, terrorism, energy, and the environment : 2007.

    SciTech Connect (OSTI)

    Herron, Kerry Gale; Jenkins-Smith, Hank C.

    2008-01-01

    We analyze and compare findings from identical national surveys of the US general public on nuclear security and terrorism administered by telephone and Internet in mid-2007. Key areas of investigation include assessments of threats to US security; valuations of US nuclear weapons and nuclear deterrence; perspectives on nuclear proliferation, including the specific cases of North Korea and Iran; and support for investments in nuclear weapons capabilities. Our analysis of public views on terrorism include assessments of the current threat, progress in the struggle against terrorism, preferences for responding to terrorist attacks at different levels of assumed casualties, and support for domestic policies intended to reduce the threat of terrorism. Also we report findings from an Internet survey conducted in mid 2007 that investigates public views of US energy security, to include: energy supplies and reliability; energy vulnerabilities and threats, and relationships among security, costs, energy dependence, alternative sources, and research and investment priorities. We analyze public assessments of nuclear energy risks and benefits, nuclear materials management issues, and preferences for the future of nuclear energy in the US. Additionally, we investigate environmental issues as they relate to energy security, to include expected implications of global climate change, and relationships among environmental issues and potential policy options.

  15. Monitoring method and apparatus using high-frequency carrier

    DOE Patents [OSTI]

    Haynes, Howard D.

    1996-01-01

    A method and apparatus for monitoring an electrical-motor-driven device by injecting a high frequency carrier signal onto the power line current. The method is accomplished by injecting a high frequency carrier signal onto an AC power line current. The AC power line current supplies the electrical-motor-driven device with electrical energy. As a result, electrical and mechanical characteristics of the electrical-motor-driven device modulate the high frequency carrier signal and the AC power line current. The high frequency carrier signal is then monitored, conditioned and demodulated. Finally, the modulated high frequency carrier signal is analyzed to ascertain the operating condition of the electrical-motor-driven device.

  16. Monitoring method and apparatus using high-frequency carrier

    DOE Patents [OSTI]

    Haynes, H.D.

    1996-04-30

    A method and apparatus for monitoring an electrical-motor-driven device by injecting a high frequency carrier signal onto the power line current. The method is accomplished by injecting a high frequency carrier signal onto an AC power line current. The AC power line current supplies the electrical-motor-driven device with electrical energy. As a result, electrical and mechanical characteristics of the electrical-motor-driven device modulate the high frequency carrier signal and the AC power line current. The high frequency carrier signal is then monitored, conditioned and demodulated. Finally, the modulated high frequency carrier signal is analyzed to ascertain the operating condition of the electrical-motor-driven device. 6 figs.

  17. High resolution, multiple-energy linear sweep detector for x-ray imaging

    DOE Patents [OSTI]

    Perez-Mendez, Victor; Goodman, Claude A.

    1996-01-01

    Apparatus for generating plural electrical signals in a single scan in response to incident X-rays received from an object. Each electrical signal represents an image of the object at a different range of energies of the incident X-rays. The apparatus comprises a first X-ray detector, a second X-ray detector stacked upstream of the first X-ray detector, and an X-ray absorber stacked upstream of the first X-ray detector. The X-ray absorber provides an energy-dependent absorption of the incident X-rays before they are incident at the first X-ray detector, but provides no absorption of the incident X-rays before they are incident at the second X-ray detector. The first X-ray detector includes a linear array of first pixels, each of which produces an electrical output in response to the incident X-rays in a first range of energies. The first X-ray detector also includes a circuit that generates a first electrical signal in response to the electrical output of each of the first pixels. The second X-ray detector includes a linear array of second pixels, each of which produces an electrical output in response to the incident X-rays in a second range of energies, broader than the first range of energies. The second X-ray detector also includes a circuit that generates a second electrical signal in response to the electrical output of each of the second pixels.

  18. High resolution, multiple-energy linear sweep detector for x-ray imaging

    DOE Patents [OSTI]

    Perez-Mendez, V.; Goodman, C.A.

    1996-08-20

    Apparatus is disclosed for generating plural electrical signals in a single scan in response to incident X-rays received from an object. Each electrical signal represents an image of the object at a different range of energies of the incident X-rays. The apparatus comprises a first X-ray detector, a second X-ray detector stacked upstream of the first X-ray detector, and an X-ray absorber stacked upstream of the first X-ray detector. The X-ray absorber provides an energy-dependent absorption of the incident X-rays before they are incident at the first X-ray detector, but provides no absorption of the incident X-rays before they are incident at the second X-ray detector. The first X-ray detector includes a linear array of first pixels, each of which produces an electrical output in response to the incident X-rays in a first range of energies. The first X-ray detector also includes a circuit that generates a first electrical signal in response to the electrical output of each of the first pixels. The second X-ray detector includes a linear array of second pixels, each of which produces an electrical output in response to the incident X-rays in a second range of energies, broader than the first range of energies. The second X-ray detector also includes a circuit that generates a second electrical signal in response to the electrical output of each of the second pixels. 12 figs.

  19. John Papanikolas: Visualizing Charge Carrier Motion in Nanowires Using

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

    Femtosecond Pump-Probe Microscopy | Center for Energy Efficient Materials John Papanikolas: Visualizing Charge Carrier Motion in Nanowires Using Femtosecond Pump-Probe Microscopy Apr 17, 2014 | 4:00 PM - 5:00 PM John Papanikolas Professor of Chemistry & Deputy Director, EFRC on Solar Fuels University of North Carolina, Chapel Hill Visualizing Charge Carrier Motion in Nanowires Using Femtosecond Pump-Probe Microscopy April 17, 2014 | 4:00pm | ESB 1001 Faculty host: Dan Morse

  20. A Spintronic Semiconductor with Selectable Charge Carriers

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

    A Spintronic Semiconductor with Selectable Charge Carriers A Spintronic Semiconductor with Selectable Charge Carriers Print Wednesday, 28 August 2013 00:00 Accentuating the ...

  1. Stable wafer-carrier system

    DOE Patents [OSTI]

    Rozenzon, Yan; Trujillo, Robert T; Beese, Steven C

    2013-10-22

    One embodiment of the present invention provides a wafer-carrier system used in a deposition chamber for carrying wafers. The wafer-carrier system includes a base susceptor and a top susceptor nested inside the base susceptor with its wafer-mounting side facing the base susceptor's wafer-mounting side, thereby forming a substantially enclosed narrow channel. The base susceptor provides an upward support to the top susceptor.

  2. Evaluating Solar Resource Data Obtained from Multiple Radiometers Deployed at the National Renewable Energy Laboratory: Preprint

    SciTech Connect (OSTI)

    Habte, A.; Sengupta, M.; Andreas, A.; Wilcox, S.; Stoffel, T.

    2014-09-01

    Solar radiation resource measurements from radiometers are used to predict and evaluate the performance of photovoltaic and concentrating solar power systems, validate satellite-based models for estimating solar resources, and advance research in solar forecasting and climate change. This study analyzes the performance of various commercially available radiometers used for measuring global horizontal irradiances (GHI) and direct normal irradiances (DNI). These include pyranometers, pyrheliometers, rotating shadowband irradiometers, and a pyranometer with a shading ring deployed at the National Renewable Energy Laboratory's Solar Radiation Research Laboratory (SRRL). The radiometers in this study were deployed for one year (from April 1, 2011, through March 31, 2012) and compared to measurements from radiometers with the lowest values of estimated measurement uncertainties for producing reference GHI and DNI.

  3. Conservation laws and multiplicity evolution of spectra at energies available at the BNL Relativistic Heavy Ion Collider

    SciTech Connect (OSTI)

    Chajecki, Zbigniew; Lisa, Mike

    2009-03-15

    Transverse momentum distributions in ultrarelativistic heavy ion collisions carry considerable information about the dynamics of the hot system produced. Direct comparison with the same spectra from p+p collisions has proved invaluable in identifying novel features associated with the larger system, in particular, the 'jet quenching' at high momentum and the apparently much stronger collective flow dominating the spectral shape at low momentum. We point out possible hazards of ignoring conservation laws in the comparison of high- and low-multiplicity final states. We argue that the effects of energy and momentum conservation actually dominate many of the observed systematics, and that p+p collisions may be much more similar to heavy ion collisions than generally thought.

  4. Theoretical and experimental study of dynamics of photoexcited carriers in GaN

    SciTech Connect (OSTI)

    Shishehchi, Sara; Bellotti, Enrico; Rudin, Sergey; Garrett, Gregory A.; Wraback, Michael

    2013-12-21

    We present a theoretical and experimental study of the sub-picosecond dynamics of photo-excited carriers in GaN. In the theoretical model, interaction with an external ultrafast laser pulse is treated coherently and to account for the scattering mechanisms and dephasing processes, a generalized Monte-Carlo simulation is used. The scattering mechanisms included are carrier interactions with polar optical phonons and acoustic phonons, and carrier-carrier Coulomb interactions. We study the effect of different scattering mechanisms on the carrier densities. In the case that the excitation energy satisfies the threshold for polar optical scattering, phonon contribution is the dominant process in relaxing the system, otherwise, carrier-carrier mechanism is dominant. Furthermore, we present the temperature and pulse power dependent normalized luminescence intensity. The results are presented over a range of temperatures, electric field, and excitation energy of the laser pulse. For comparison, we also report the experimental time-resolved photoluminescence studies on GaN samples. There is a good agreement between the simulation and experiment in normalized luminescence intensity results. Therefore, we show that we can explain the dynamics of the photo-excited carriers in GaN by including only carrier-carrier and carrier-phonon interactions and a relatively simple two-band electronic structure model.

  5. Carrier sense data highway system

    DOE Patents [OSTI]

    Frankel, Robert

    1984-02-14

    A data transmission system includes a transmission medium which has a certain propagation delay time over its length. A number of data stations are successively coupled to the transmission medium for communicating with one another. Each of the data stations includes a transmitter for originating signals, each signal beginning with a carrier of a duration which is at least the propagation delay time of the transmission medium. Each data station also includes a receiver which receives other signals from other data stations and inhibits operation of the transmitter at the same data station when a carrier of another signal is received.

  6. Apparatus for measuring minority carrier lifetime using liquid conductor -

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

    Energy Innovation Portal Industrial Technologies Industrial Technologies Find More Like This Return to Search Apparatus for measuring minority carrier lifetime using liquid conductor National Renewable Energy Laboratory Contact NREL About This Technology Technology Marketing Summary Solar power generating capacity has grown from 83 MW in 2003 to over 7,200 MW in 2012, in the U.S. alone. As the solar industry grows, there is a significant need for quality control and testing methodologies.

  7. Non-permeable substrate carrier for electroplating

    DOE Patents [OSTI]

    Abas, Emmanuel Chua; Chen, Chen-An; Ma, Diana Xiaobing; Ganti, Kalyana Bhargava

    2012-11-27

    One embodiment relates to a substrate carrier for use in electroplating a plurality of substrates. The substrate carrier comprises a non-conductive carrier body on which the substrates are to be held. Electrically-conductive lines are embedded within the carrier body, and a plurality of contact clips are coupled to the electrically-conductive lines embedded within the carrier body. The contact clips hold the substrates in place and electrically couple the substrates to the electrically-conductive lines. The non-conductive carrier body is continuous so as to be impermeable to flow of electroplating solution through the non-conductive carrier body. Other embodiments, aspects and features are also disclosed.

  8. Non-permeable substrate carrier for electroplating

    DOE Patents [OSTI]

    Abas, Emmanuel Chua; Chen, Chen-an; Ma, Diana Xiaobing; Ganti, Kalyana; Divino, Edmundo Anida; Ermita, Jake Randal G.; Capulong, Jose Francisco S.; Castillo, Arnold Villamor

    2015-12-29

    One embodiment relates to a substrate carrier for use in electroplating a plurality of substrates. The substrate carrier comprises a non-conductive carrier body on which the substrates are to be held. Electrically-conductive lines are embedded within the carrier body, and a plurality of contact clips are coupled to the electrically-conductive lines embedded within the carrier body. The contact clips hold the substrates in place and electrically couple the substrates to the electrically-conductive lines. The non-conductive carrier body is continuous so as to be impermeable to flow of electroplating solution through the non-conductive carrier body. Other embodiments, aspects and features are also disclosed.

  9. Silicon ball grid array chip carrier

    DOE Patents [OSTI]

    Palmer, David W.; Gassman, Richard A.; Chu, Dahwey

    2000-01-01

    A ball-grid-array integrated circuit (IC) chip carrier formed from a silicon substrate is disclosed. The silicon ball-grid-array chip carrier is of particular use with ICs having peripheral bond pads which can be reconfigured to a ball-grid-array. The use of a semiconductor substrate such as silicon for forming the ball-grid-array chip carrier allows the chip carrier to be fabricated on an IC process line with, at least in part, standard IC processes. Additionally, the silicon chip carrier can include components such as transistors, resistors, capacitors, inductors and sensors to form a "smart" chip carrier which can provide added functionality and testability to one or more ICs mounted on the chip carrier. Types of functionality that can be provided on the "smart" chip carrier include boundary-scan cells, built-in test structures, signal conditioning circuitry, power conditioning circuitry, and a reconfiguration capability. The "smart" chip carrier can also be used to form specialized or application-specific ICs (ASICs) from conventional ICs. Types of sensors that can be included on the silicon ball-grid-array chip carrier include temperature sensors, pressure sensors, stress sensors, inertia or acceleration sensors, and/or chemical sensors. These sensors can be fabricated by IC processes and can include microelectromechanical (MEM) devices.

  10. Lattice and Carrier Dynamics in Quantum-Confined Materials on Ultrafast

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

    Timescales | MIT-Harvard Center for Excitonics Lattice and Carrier Dynamics in Quantum-Confined Materials on Ultrafast Timescales April 3, 2014 at 3pm/36-428 Richard Schaller Department of Chemistry, Northwestern University, Argonne National Laboratory richard-schaller_000 Abstract: Excess carrier energy, which many aim to utilize for advanced energy conversion technologies, rapidly dissipates from electrons and holes in both bulk and quantum confined semiconductors despite expectation of

  11. Photovoltaics: Separating Multiple Excitons

    SciTech Connect (OSTI)

    Nozik, A. J.

    2012-05-01

    Scientists have demonstrated an efficient process for generating multiple excitons in adjacent silicon nanocrystals from a single high-energy photon. Their findings could prove useful for a wide range of photovoltaic applications.

  12. A Spintronic Semiconductor with Selectable Charge Carriers

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

    A Spintronic Semiconductor with Selectable Charge Carriers Print Accentuating the Positive ... Strategies for developing spintronic semiconductors have been based on surface doping or ...

  13. Analysis of carrier transport and carrier trapping in organic diodes with polyimide-6,13-Bis(triisopropylsilylethynyl)pentacene double-layer by charge modulation spectroscopy and optical second harmonic generation measurement

    SciTech Connect (OSTI)

    Lim, Eunju E-mail: taguchi.d.aa@m.titech.ac.jp; Taguchi, Dai E-mail: taguchi.d.aa@m.titech.ac.jp Iwamoto, Mitsumasa E-mail: taguchi.d.aa@m.titech.ac.jp

    2014-08-18

    We studied the carrier transport and carrier trapping in indium tin oxide/polyimide (PI)/6,13-Bis(triisopropylsilylethynyl)pentacene (TIPS-pentacene)/Au diodes by using charge modulation spectroscopy (CMS) and time-resolved electric field induced optical second harmonic generation (TR-EFISHG) measurements. TR-EFISHG directly probes the spatial carrier behaviors in the diodes, and CMS is useful in explaining the carrier motion with respect to energy. The results clearly indicate that the injected carriers move across TIPS-pentacene thorough the molecular energy states of TIPS-pentacene and accumulate at the PI/TIPS-pentacene interface. However, some carriers are trapped in the PI layers. These findings take into account the capacitance-voltage and current-voltage characteristics of the diodes.

  14. Experimental demonstration of hot-carrier photo-current in an InGaAs quantum well solar cell

    SciTech Connect (OSTI)

    Hirst, L. C.; Walters, R. J.; Führer, M. F.; Ekins-Daukes, N. J.

    2014-06-09

    An unambiguous observation of hot-carrier photocurrent from an InGaAs single quantum well solar cell is reported. Simultaneous photo-current and photoluminescence measurements were performed for incident power density 0.04–3 kW cm{sup −2}, lattice temperature 10 K, and forward bias 1.2 V. An order of magnitude photocurrent increase was observed for non-equilibrium hot-carrier temperatures >35 K. This photocurrent activation temperature is consistent with that of equilibrium carriers in a lattice at elevated temperature. The observed hot-carrier photo-current is extracted from the well over an energy selective GaAs barrier, thus integrating two essential components of a hot-carrier solar cell: a hot-carrier absorber and an energy selective contact.

  15. Detection of minority carrier traps in p-type 4H-SiC

    SciTech Connect (OSTI)

    Alfieri, G.; Kimoto, T.

    2014-03-03

    Contrarily to the case of n-type 4H-SiC, very little is known about the presence of minority carrier traps in p-type epilayers. In this study, we performed the electrical characterization of as-grown, electron irradiated, and thermally oxidized p-type 4H-SiC, by using minority carrier transient spectroscopy. Four minority carrier traps are reported in 1.6–2.3 eV energy range above the valence band edge (E{sub V}). Particular emphasis is given to the mid-gap minority carrier trap (EH{sub 6∕7}) and to its correlation to an energetically close mid-gap majority carrier trap (HK4)

  16. Forward energy flow, central charged-particle multiplicities, and pseudorapidity gaps in W and Z boson events from pp collisions at $\\sqrt{s}= 7$ TeV

    SciTech Connect (OSTI)

    Chatrchyan, Serguei; et al.

    2012-01-01

    A study of forward energy flow and central charged-particle multiplicity in events with W and Z bosons decaying into leptons is presented. The analysis uses a sample of 7 TeV pp collisions, corresponding to an integrated luminosity of 36 inverse picobarns, recorded by the CMS experiment at the LHC. The observed forward energy depositions, their correlations, and the central charged-particle multiplicities are not well described by the available non-diffractive soft-hadron production models. A study of about 300 events with no significant energy deposited in one of the forward calorimeters, corresponding to a pseudorapidity gap of at least 1.9 units, is also presented. An indication for a diffractive component in these events comes from the observation that the majority of the charged leptons from the (W/Z) decays are found in the hemisphere opposite to the gap. When fitting the signed lepton pseudorapidity distribution of these events with predicted distributions from an admixture of diffractive (POMPYT) and non-diffractive (PYTHIA) Monte Carlo simulations, the diffractive component is determined to be (50.0 +/- 9.3 (stat.) +/- 5.2 (syst.))%.

  17. Multiplicity Counting

    SciTech Connect (OSTI)

    Geist, William H.

    2015-12-01

    This set of slides begins by giving background and a review of neutron counting; three attributes of a verification item are discussed: 240Pueff mass; α, the ratio of (α,n) neutrons to spontaneous fission neutrons; and leakage multiplication. It then takes up neutron detector systems – theory & concepts (coincidence counting, moderation, die-away time); detector systems – some important details (deadtime, corrections); introduction to multiplicity counting; multiplicity electronics and example distributions; singles, doubles, and triples from measured multiplicity distributions; and the point model: multiplicity mathematics.

  18. Lateral carrier confinement in InGaN quantum-well nanorods

    SciTech Connect (OSTI)

    Shi, Chentian; Zhang, Chunfeng; Wang, Xiaoyong; Xiao, Min

    2015-07-15

    We review our studies on lateral carrier diffusion in micro-fabricated samples of InGaN nanorods and their parent quantum wells. The carrier diffusion is observed to be strongly confined in nanorods, as manifested by the reduction in the delayed-rise component of time-resolved photoluminescence traces. We further argue that the confinement of carrier diffusion can be applied to suppress the efficiency droop related to defect state recombination and to assist in the energy transfer between InGaN nanorods and nanocrystal phosphors for color conversion.

  19. Past Events | Center for Energy Efficient Materials

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

    Seminar Series John Papanikolas: Visualizing Charge Carrier Motion in Nanowires Using ... Personal Perspectives on Advancing Energy Sustainability Seminar Series Vidvuds ...

  20. Carrier Density Modulation in Ge Heterostructure by Ferroelectric Switching

    SciTech Connect (OSTI)

    Ponath, Patrick; Fredrickson, Kurt; Posadas, Agham B.; Ren, Yuan; Vasudevan, Rama K; Okatan, Mahmut Baris; Jesse, Stephen; Aoki, Toshihiro; McCartney, Martha; Smith, David J; Kalinin, Sergei V; Lai, Keji; Demkov, Alexander A.

    2015-01-01

    The development of nonvolatile logic through direct coupling of spontaneous ferroelectric polarization with semiconductor charge carriers is nontrivial, with many issues, including epitaxial ferroelectric growth, demonstration of ferroelectric switching, and measurable semiconductor modulation. Here we report a true ferroelectric field effect carrier density modulation in an underlying Ge(001) substrate by switching of the ferroelectric polarization in the epitaxial c-axis-oriented BaTiO3 (BTO) grown by molecular beam epitaxy (MBE) on Ge. Using density functional theory, we demonstrate that switching of BTO polarization results in a large electric potential change in Ge. Aberration-corrected electron microscopy confirms the interface sharpness, and BTO tetragonality. Electron-energy-loss spectroscopy (EELS) indicates the absence of any low permittivity interlayer at the interface with Ge. Using piezoelectric force microscopy (PFM), we confirm the presence of fully switchable, stable ferroelectric polarization in BTO that appears to be single domain. Using microwave impedance microscopy (MIM), we clearly demonstrate a ferroelectric field effect.

  1. Simplified 2DEG carrier concentration model for composite barrier AlGaN/GaN HEMT

    SciTech Connect (OSTI)

    Das, Palash Biswas, Dhrubes

    2014-04-24

    The self consistent solution of Schrodinger and Poisson equations is used along with the total charge depletion model and applied with a novel approach of composite AlGaN barrier based HEMT heterostructure. The solution leaded to a completely new analytical model for Fermi energy level vs. 2DEG carrier concentration. This was eventually used to demonstrate a new analytical model for the temperature dependent 2DEG carrier concentration in AlGaN/GaN HEMT.

  2. Gas energy meter for inferential determination of thermophysical properties of a gas mixture at multiple states of the gas

    DOE Patents [OSTI]

    Morrow, Thomas B.; Kelner, Eric; Owen, Thomas E.

    2008-07-08

    A gas energy meter that acquires the data and performs the processing for an inferential determination of one or more gas properties, such as heating value, molecular weight, or density. The meter has a sensor module that acquires temperature, pressure, CO2, and speed of sound data. Data is acquired at two different states of the gas, which eliminates the need to determine the concentration of nitrogen in the gas. A processing module receives this data and uses it to perform a "two-state" inferential algorithm.

  3. A Spintronic Semiconductor with Selectable Charge Carriers

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

    spin-up and spin-down states as well as both positive and negative charge carriers. Strategies for developing spintronic semiconductors have been based on surface doping or...

  4. Charge carrier coherence and Hall effect in organic semiconductors...

    Office of Scientific and Technical Information (OSTI)

    Charge carrier coherence and Hall effect in organic semiconductors Citation Details In-Document Search Title: Charge carrier coherence and Hall effect in organic semiconductors ...

  5. Time-resolved carrier distributions in graphene (Conference)...

    Office of Scientific and Technical Information (OSTI)

    Time-resolved carrier distributions in graphene Citation Details In-Document Search Title: Time-resolved carrier distributions in graphene You are accessing a document from the ...

  6. Final Report - Three-dimensional minority carrier lifetime mapping...

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

    Three-dimensional minority carrier lifetime mapping of thin film semiconductors for solar cell applications Final Report - Three-dimensional minority carrier lifetime mapping of ...

  7. A Spintronic Semiconductor with Selectable Charge Carriers

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

    A Spintronic Semiconductor with Selectable Charge Carriers A Spintronic Semiconductor with Selectable Charge Carriers Print Wednesday, 28 August 2013 00:00 Accentuating the Positive (or the Negative) Spintronics-a type of electronics that makes use of electron spin as well as charge-is already here to a certain extent. The discovery of giant magnetoresistance, a spin-based effect, has revolutionized the information storage industry. Beyond this, however, scientists envision the possibility of

  8. Strong carrier localization effect in carrier dynamics of 585 nm InGaN amber light-emitting diodes

    SciTech Connect (OSTI)

    Li, Panpan; Li, Hongjian; Li, Zhi; Kang, Junjie; Yi, Xiaoyan; Li, Jinmin; Wang, Guohong

    2015-02-21

    Temperature dependence and time-resolved photoluminescence (TRPL) have been carried out to study carrier dynamics for 585 nm InGaN amber light-emitting diodes (LEDs). It is found that in InGaN amber LEDs, peak emission energy only shows a slight blueshift from 588 to 575 nm, as temperature increased from 10 K to 300 K. Moreover, radiative recombination lifetime has demonstrated independent of temperature based TRPL results. These two features indicate that a strong carrier localization effect plays a dominant role in carrier dynamics for InGaN amber LEDs. Also, activation energy of 40.3 meV is obtained through Arrhenius plot of PL intensity versus temperature.

  9. SLS complementary logic devices with increase carrier mobility

    DOE Patents [OSTI]

    Chaffin, Roger J.; Osbourn, Gordon C.; Zipperian, Thomas E.

    1991-01-01

    In an electronic device comprising a semiconductor material and having at least one performance characteristic which is limited by the mobility of holes in the semiconductor material, said mobility being limited because of a valence band degeneracy among high-mobility and low-mobility energy levels accessible to said holes at the energy-momentum space maximum, an improvement is provided wherein the semiconductor material is a strained layer superlattice (SLS) whose layer compositions and layer thicknesses are selected so that the strain on the layers predominantly containing said at least one carrier type splits said degeneracy and modifies said energy levels around said energy-momentum space maximum in a manner whereby said limitation on the mobility of said holes is alleviated.

  10. SLS complementary logic devices with increase carrier mobility

    DOE Patents [OSTI]

    Chaffin, R.J.; Osbourn, G.C.; Zipperian, T.E.

    1991-07-09

    In an electronic device comprising a semiconductor material and having at least one performance characteristic which is limited by the mobility of holes in the semiconductor material, said mobility being limited because of a valence band degeneracy among high-mobility and low-mobility energy levels accessible to said holes at the energy-momentum space maximum, an improvement is provided wherein the semiconductor material is a strained layer superlattice (SLS) whose layer compositions and layer thicknesses are selected so that the strain on the layers predominantly containing said at least one carrier type splits said degeneracy and modifies said energy levels around said energy-momentum space maximum in a manner whereby said limitation on the mobility of said holes is alleviated. 5 figures.

  11. Design of novel nano-carriers for multi-enzyme co-localization

    SciTech Connect (OSTI)

    Jia, Feng

    2013-01-01

    The main objective of this project is to design novel nano-structured carriers and strategies to co-localize multiple enzymes to mimic the functionalities of MECs. In order to achieve this goal, distinct approaches for enzyme co-localization were developed and evaluated. Specifically, we investigated different polymeric nano-carriers, both flexible and rigid, as platforms for co-localization, as well as distinct enzyme attachment techniques using model enzyme systems using glucose oxidase and horseradish peroxidase to control the spatial arrangement of the multiple enzymes on the nanocarriers. This platform technology can be potentially used to co-localize various enzyme systems and its broad applicability will be tested using the sclareol biosynthesis process to control the formation of products through the formation of MECs with multiple enzymes NgCPS and sSsSS to regulate the pathway of reactive intermediate to enhance the final product conversion rate.

  12. Multiple resonant railgun power supply

    DOE Patents [OSTI]

    Honig, E.M.; Nunnally, W.C.

    1985-06-19

    A multiple repetitive resonant railgun power supply provides energy for repetitively propelling projectiles from a pair of parallel rails. A plurality of serially connected paired parallel rails are powered by similar power supplies. Each supply comprises an energy storage capacitor, a storage inductor to form a resonant circuit with the energy storage capacitor and a magnetic switch to transfer energy between the resonant circuit and the pair of parallel rails for the propelling of projectiles. The multiple serial operation permits relatively small energy components to deliver overall relatively large amounts of energy to the projectiles being propelled.

  13. Multiple resonant railgun power supply

    DOE Patents [OSTI]

    Honig, Emanuel M. (Los Alamos, NM); Nunnally, William C. (Los Alamos, NM)

    1988-01-01

    A multiple repetitive resonant railgun power supply provides energy for repetitively propelling projectiles from a pair of parallel rails. A plurality of serially connected paired parallel rails are powered by similar power supplies. Each supply comprises an energy storage capacitor, a storage inductor to form a resonant circuit with the energy storage capacitor and a magnetic switch to transfer energy between the resonant circuit and the pair of parallel rails for the propelling of projectiles. The multiple serial operation permits relatively small energy components to deliver overall relatively large amounts of energy to the projectiles being propelled.

  14. Transverse energy production and charged-particle multiplicity at midrapidity in various systems from sNN=7.7 to 200 GeV

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

    Adare, A.; Afanasiev, S.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Akimoto, R.; Al-Bataineh, H.; Alexander, J.; Alfred, M.; Al-Jamel, A.; et al

    2016-02-03

    Measurements of midrapidity charged-particle multiplicity distributions, dNch/dη, and midrapidity transverse-energy distributions, dET/dη, are presented for a variety of collision systems and energies. Included are distributions for Au+Au collisions at √sNN=200, 130, 62.4, 39, 27, 19.6, 14.5, and 7.7 GeV, Cu+Cu collisions at √sNN=200 and 62.4 GeV, Cu+Au collisions at √sNN=200 GeV, U+U collisions at√sNN=193 GeV, d+Au collisions at √sNN=200 GeV, He3+Au collisions at √sNN=200 GeV, and p+p collisions at √sNN=200 GeV. We present centrality-dependent distributions at midrapidity in terms of the number of nucleon participants, Npart, and the number of constituent quark participants, Nqp. For all A+A collisions down tomore » √sNN=7.7 GeV, we observed that the midrapidity data are better described by scaling with Nqp than scaling with Npart. Finally, our estimates of the Bjorken energy density, εBJ, and the ratio of dET/dη to dNch/dη are presented, the latter of which is seen to be constant as a function of centrality for all systems.« less

  15. Carrier redistribution between different potential sites in semipolar (202{sup ¯}1) InGaN quantum wells studied by near-field photoluminescence

    SciTech Connect (OSTI)

    Marcinkevičius, S.; Gelžinytė, K.; Zhao, Y.; Nakamura, S.; DenBaars, S. P.; Speck, J. S.

    2014-09-15

    Scanning near-field photoluminescence (PL) spectroscopy at different excitation powers was applied to study nanoscale properties of carrier localization and recombination in semipolar (202{sup ¯}1) InGaN quantum wells (QWs) emitting in violet, blue, and green-yellow spectral regions. With increased excitation power, an untypical PL peak energy shift to lower energies was observed. The shift was attributed to carrier density dependent carrier redistribution between nm-scale sites of different potentials. Near-field PL scans showed that in (202{sup ¯}1) QWs the in-plane carrier diffusion is modest, and the recombination properties are uniform, which is advantageous for photonic applications.

  16. BISMUTH PHOSPHATE CARRIER PROCESS FOR Pu RECOVERY

    DOE Patents [OSTI]

    Finzel, T.G.

    1959-02-01

    An improvement in the bismuth phosphate carrier precipitation process for recovering plutonium is described. It has been found that a more granular and more easily filterable carrier precipitiite is formed if the addition of the bismuth and phosphate ions is effected by first adding 9/10 of the bismuth ions necessary, then slowly adding all of the source of the phosphate ions to be incorporated in the precipitate, while digesting at 75 C and afterwards incorporating the remainder of the total bismuth ions necessary

  17. OLED Deposition Technology - Energy Innovation Portal

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

    Industrial Technologies Industrial Technologies Energy Storage Energy Storage Advanced ... compound with a fluid carrier into a "hot box" that converts the mixture to the gas phase. ...

  18. Multiple-Filled Skutterudites: High Thermoelectric Figure of Merit through Separately Optimizing Electrical and Thermal Transports

    SciTech Connect (OSTI)

    Zhang, Weiqing; Yang, Jiong; Yang, Jihui; Wang, Hsin; Salvador, James R.; Shi, Xun; Chi, Miaofang; Cho, Jung Y; Bai, Shengqiang; Chen, Lidong

    2011-01-01

    Skutterudites CoSb{sub 3} with multiple cofillers Ba, La, and Yb were synthesized and very high thermoelectric figure of merit ZT = 1.7 at 850 K was realized. X-ray diffraction of the densified multiple-filled bulk samples reveals all samples are phase pure. High-resolution scanning transmission electron microscopy (STEM) and energy dispersive X-ray spectroscopy (EDS) analysis confirm that multiple guest fillers occupy the nanoscale-cages in the skutterudites. The fillers are further shown to be uniformly distributed and the Co-Sb skutterudite framework is virtually unperturbed from atomic scale to a few micrometers. Our results firmly show that high power factors can be realized by adjusting the total filling fraction of fillers with different charge states to reach the optimum carrier density, at the same time, lattice thermal conductivity can also be significantly reduced, to values near the glass limit of these materials, through combining filler species of different rattling frequencies to achieve broad-frequency phonon scattering. Therefore, partially filled skutterudites with multiple fillers of different chemical nature render unique structural characteristics for optimizing electrical and thermal transports in a relatively independent way, leading to continually enhanced ZT values from single- to double-, and finally to multiple-filled skutterudites. The idea of combining multiple fillers with different charge states and rattling frequencies for performance optimization is also expected to be valid for other caged TE compounds.

  19. Transport-reaction model for defect and carrier behavior within displacement cascades in gallium arsenide

    SciTech Connect (OSTI)

    Wampler, William R.; Myers, Samuel M.

    2014-02-01

    A model is presented for recombination of charge carriers at displacement damage in gallium arsenide, which includes clustering of the defects in atomic displacement cascades produced by neutron or ion irradiation. The carrier recombination model is based on an atomistic description of capture and emission of carriers by the defects with time evolution resulting from the migration and reaction of the defects. The physics and equations on which the model is based are presented, along with details of the numerical methods used for their solution. The model uses a continuum description of diffusion, field-drift and reaction of carriers and defects within a representative spherically symmetric cluster. The initial radial defect profiles within the cluster were chosen through pair-correlation-function analysis of the spatial distribution of defects obtained from the binary-collision code MARLOWE, using recoil energies for fission neutrons. Charging of the defects can produce high electric fields within the cluster which may influence transport and reaction of carriers and defects, and which may enhance carrier recombination through band-to-trap tunneling. Properties of the defects are discussed and values for their parameters are given, many of which were obtained from density functional theory. The model provides a basis for predicting the transient response of III-V heterojunction bipolar transistors to pulsed neutron irradiation.

  20. Injection deep level transient spectroscopy: An improved method for measuring capture rates of hot carriers in semiconductors

    SciTech Connect (OSTI)

    Fleming, R. M.; Seager, C. H.; Lang, D. V.; Campbell, J. M.

    2015-07-07

    An improved method for measuring the cross sections for carrier trapping at defects in semiconductors is described. This method, a variation of deep level transient spectroscopy (DLTS) used with bipolar transistors, is applied to hot carrier trapping at vacancy-oxygen, carbon-oxygen, and three charge states of divacancy centers (V{sub 2}) in n- and p-type silicon. Unlike standard DLTS, we fill traps by injecting carriers into the depletion region of a bipolar transistor diode using a pulse of forward bias current applied to the adjacent diode. We show that this technique is capable of accurately measuring a wide range of capture cross sections at varying electric fields due to the control of the carrier density it provides. Because this technique can be applied to a variety of carrier energy distributions, it should be valuable in modeling the effect of radiation-induced generation-recombination currents in bipolar devices.

  1. Injection deep level transient spectroscopy: An improved method for measuring capture rates of hot carriers in semiconductors

    SciTech Connect (OSTI)

    Fleming, R. M.; Seager, C. H.; Lang, D. V.; Campbell, J. M.

    2015-07-02

    In this study, an improved method for measuring the cross sections for carrier trapping at defects in semiconductors is described. This method, a variation of deep level transient spectroscopy(DLTS) used with bipolar transistors, is applied to hot carrier trapping at vacancy-oxygen, carbon-oxygen, and three charge states of divacancy centers (V2) in n- and p-type silicon. Unlike standard DLTS, we fill traps by injecting carriers into the depletion region of a bipolar transistor diode using a pulse of forward bias current applied to the adjacent diode. We show that this technique is capable of accurately measuring a wide range of capture cross sections at varying electric fields due to the control of the carrier density it provides. Because this technique can be applied to a variety of carrier energy distributions, it should be valuable in modeling the effect of radiation-induced generation-recombination currents in bipolar devices.

  2. Experimental evidence of hot carriers solar cell operation in multi-quantum wells heterostructures

    SciTech Connect (OSTI)

    Rodière, Jean; Lombez, Laurent; Le Corre, Alain; Durand, Olivier; Guillemoles, Jean-François

    2015-05-04

    We investigated a semiconductor heterostructure based on InGaAsP multi quantum wells (QWs) using optical characterizations and demonstrate its potential to work as a hot carrier cell absorber. By analyzing photoluminescence spectra, the quasi Fermi level splitting Δμ and the carrier temperature are quantitatively measured as a function of the excitation power. Moreover, both thermodynamics values are measured at the QWs and the barrier emission energy. High values of Δμ are found for both transition, and high carrier temperature values in the QWs. Remarkably, the quasi Fermi level splitting measured at the barrier energy exceeds the absorption threshold of the QWs. This indicates a working condition beyond the classical Shockley-Queisser limit.

  3. URANOUS IODATE AS A CARRIER FOR PLUTONIUM

    DOE Patents [OSTI]

    Miller, D.R.; Seaborg, G.T.; Thompson, S.G.

    1959-12-15

    A process is described for precipitating plutonium on a uranous iodate carrier from an aqueous acid solution conA plutonium solution more concentrated than the original solution can then be obtained by oxidizing the uranium to the hexavalent state and dissolving the precipitate, after separating the latter from the original solution, by means of warm nitric acid.

  4. Recovery Act: Novel Oxygen Carriers for Coal-fueled Chemical Looping

    SciTech Connect (OSTI)

    Pan, Wei-Ping; Cao, Yan

    2012-11-30

    Chemical Looping Combustion (CLC) could totally negate the necessity of pure oxygen by using oxygen carriers for purification of CO{sub 2} stream during combustion. It splits the single fuel combustion reaction into two linked reactions using oxygen carriers. The two linked reactions are the oxidation of oxygen carriers in the air reactor using air, and the reduction of oxygen carriers in the fuel reactor using fuels (i.e. coal). Generally metal/metal oxides are used as oxygen carriers and operated in a cyclic mode. Chemical looping combustion significantly improves the energy conversion efficiency, in terms of the electricity generation, because it improves the reversibility of the fuel combustion process through two linked parallel processes, compared to the conventional combustion process, which is operated far away from its thermo-equilibrium. Under the current carbon-constraint environment, it has been a promising carbon capture technology in terms of fuel combustion for power generation. Its disadvantage is that it is less mature in terms of technological commercialization. In this DOE-funded project, accomplishment is made by developing a series of advanced copper-based oxygen carriers, with properties of the higher oxygen-transfer capability, a favorable thermodynamics to generate high purity of CO{sub 2}, the higher reactivity, the attrition-resistance, the thermal stability in red-ox cycles and the achievement of the auto-thermal heat balance. This will be achieved into three phases in three consecutive years. The selected oxygen carriers with final-determined formula were tested in a scaled-up 10kW coal-fueled chemical looping combustion facility. This scaled-up evaluation tests (2-day, 8-hour per day) indicated that, there was no tendency of agglomeration of copper-based oxygen carriers. Only trace-amount of coke or carbon deposits on the copper-based oxygen carriers in the fuel reactor. There was also no evidence to show the sulphidization of oxygen

  5. Multiple Exciton Generation Solar Cells

    SciTech Connect (OSTI)

    Luther, J. M.; Semonin, O. E.; Beard, M. C.; Gao, J.; Nozik, A. J.

    2012-01-01

    Heat loss is the major factor limiting traditional single junction solar cells to a theoretical efficiency of 32%. Multiple Exciton Generation (MEG) enables efficient use of the solar spectrum yielding a theoretical power conversion efficiency of 44% in solar cells under 1-sun conditions. Quantum-confined semiconductors have demonstrated the ability to generate multiple carriers but present-day materials deliver efficiencies far below the SQ limit of 32%. Semiconductor quantum dots of PbSe and PbS provide an active testbed for developing high-efficiency, inexpensive solar cells benefitting from quantum confinement effects. Here, we will present recent work of solar cells employing MEG to yield external quantum efficiencies exceeding 100%.

  6. Alberta: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Ltd Energy Incentives for Alberta Energy Monitoring Act (Canada) Western Interstate Nuclear Compact State Nuclear Policy (Multiple States) References http:...

  7. Delivery Analysis | Department of Energy

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

    or expanded grid infrastructures, as hydrogen via pipeline, or as a liquid energy carrier to point-of-need reformers. Some of the delivery analyses completed to date ...

  8. New method of determining the current carrier concentration in a substance in the state of superconductivity

    SciTech Connect (OSTI)

    Golotyuk, F.P.

    1985-08-02

    This report proposes a fundamentally new solution to the problem of determining the current carrier concentration in a substance. The basis of the corresponding experimental method is a theory that considers the electron drift energy when considering the oscillatory processes in certain circuits.

  9. Ultrafast free-carrier dynamics in Cu{sub 2}ZnSnS{sub 4} single crystals studied using femtosecond time-resolved optical spectroscopy

    SciTech Connect (OSTI)

    Phuong, L. Q.; Kanemitsu, Y.; Okano, M.; Yamada, Y.; Yamashita, G.; Morimoto, T.; Nagai, M.; Ashida, M.; Nagaoka, A.; Yoshino, K.

    2014-12-08

    We studied the dynamics of photogenerated carriers in Cu{sub 2}ZnSnS{sub 4} (CZTS) single crystals using femtosecond transient reflectivity (TR) and optical pump-THz probe transient absorption (THz-TA) spectroscopy. The TR and THz-TA decay dynamics consistently showed that free carriers have long lifetimes of up to a few nanoseconds. The excitation-photon-energy-dependent TR measurements revealed a slow picosecond energy relaxation of free carriers to the band edge in CZTS. The relaxation and recombination dynamics of free carriers were affected by nonradiative recombinations at the surface. Our results revealed a global feature of energy relaxation and recombination processes of free carriers in CZTS single crystals.

  10. Electrical system for pulse-width modulated control of a power inverter using phase-shifted carrier signals and related operating methods

    DOE Patents [OSTI]

    Welchko, Brian A.

    2012-02-14

    Systems and methods are provided for pulse-width modulated control of power inverter using phase-shifted carrier signals. An electrical system comprises an energy source and a motor. The motor has a first set of windings and a second set of windings, which are electrically isolated from each other. An inverter module is coupled between the energy source and the motor and comprises a first set of phase legs coupled to the first set of windings and a second set of phase legs coupled to the second set of windings. A controller is coupled to the inverter module and is configured to achieve a desired power flow between the energy source and the motor by modulating the first set of phase legs using a first carrier signal and modulating the second set of phase legs using a second carrier signal. The second carrier signal is phase-shifted relative to the first carrier signal.

  11. Straddle Carrier Interface and Dispatching System

    Energy Science and Technology Software Center (OSTI)

    2012-09-13

    SCIDS is the Data Dispatching and Transfer Point (DDTP) component of a straddle carrier-based radiation detection system developed for the DOE Megaports Initiative for scanning shipping containers in transshipment ports. Its purpose is to communicate with a Radiation Detection Straddle Carrier (RDSC) developed by Detector Networks International, sending commands to the RDSC and receiving sensor data from the RDSC. Incoming sensor and status data from the RDSC is forwarded to a back-end data storage andmore » display system that is external to SCIDS. SCIDS provides a graphical user interface for port operations personnel that displays location and status of the RDSC and status of each container in the port, and accepts commands from the operator directing the scanning operations of the RDSC.« less

  12. A Spintronic Semiconductor with Selectable Charge Carriers

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

    A Spintronic Semiconductor with Selectable Charge Carriers Print Accentuating the Positive (or the Negative) Spintronics-a type of electronics that makes use of electron spin as well as charge-is already here to a certain extent. The discovery of giant magnetoresistance, a spin-based effect, has revolutionized the information storage industry. Beyond this, however, scientists envision the possibility of combining storage and processing functions in one integrated system. In electronics,

  13. A Spintronic Semiconductor with Selectable Charge Carriers

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

    A Spintronic Semiconductor with Selectable Charge Carriers Print Accentuating the Positive (or the Negative) Spintronics-a type of electronics that makes use of electron spin as well as charge-is already here to a certain extent. The discovery of giant magnetoresistance, a spin-based effect, has revolutionized the information storage industry. Beyond this, however, scientists envision the possibility of combining storage and processing functions in one integrated system. In electronics,

  14. A Spintronic Semiconductor with Selectable Charge Carriers

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

    A Spintronic Semiconductor with Selectable Charge Carriers Print Accentuating the Positive (or the Negative) Spintronics-a type of electronics that makes use of electron spin as well as charge-is already here to a certain extent. The discovery of giant magnetoresistance, a spin-based effect, has revolutionized the information storage industry. Beyond this, however, scientists envision the possibility of combining storage and processing functions in one integrated system. In electronics,

  15. A Spintronic Semiconductor with Selectable Charge Carriers

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

    A Spintronic Semiconductor with Selectable Charge Carriers Print Accentuating the Positive (or the Negative) Spintronics-a type of electronics that makes use of electron spin as well as charge-is already here to a certain extent. The discovery of giant magnetoresistance, a spin-based effect, has revolutionized the information storage industry. Beyond this, however, scientists envision the possibility of combining storage and processing functions in one integrated system. In electronics,

  16. A Spintronic Semiconductor with Selectable Charge Carriers

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

    A Spintronic Semiconductor with Selectable Charge Carriers Print Accentuating the Positive (or the Negative) Spintronics-a type of electronics that makes use of electron spin as well as charge-is already here to a certain extent. The discovery of giant magnetoresistance, a spin-based effect, has revolutionized the information storage industry. Beyond this, however, scientists envision the possibility of combining storage and processing functions in one integrated system. In electronics,

  17. A Spintronic Semiconductor with Selectable Charge Carriers

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

    A Spintronic Semiconductor with Selectable Charge Carriers Print Accentuating the Positive (or the Negative) Spintronics-a type of electronics that makes use of electron spin as well as charge-is already here to a certain extent. The discovery of giant magnetoresistance, a spin-based effect, has revolutionized the information storage industry. Beyond this, however, scientists envision the possibility of combining storage and processing functions in one integrated system. In electronics,

  18. A Spintronic Semiconductor with Selectable Charge Carriers

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

    A Spintronic Semiconductor with Selectable Charge Carriers Print Accentuating the Positive (or the Negative) Spintronics-a type of electronics that makes use of electron spin as well as charge-is already here to a certain extent. The discovery of giant magnetoresistance, a spin-based effect, has revolutionized the information storage industry. Beyond this, however, scientists envision the possibility of combining storage and processing functions in one integrated system. In electronics,

  19. PLUTONIUM CARRIER METATHESIS WITH ORGANIC REAGENT

    DOE Patents [OSTI]

    Thompson, S.G.

    1958-07-01

    A method is described for converting a plutonium containing bismuth phosphate carrier precipitate Into a compositton more readily soluble in acid. The method consists of dissolving the bismuth phosphate precipitate in an aqueous solution of alkali metal hydroxide, and adding one of a certaia group of organic compounds, e.g., polyhydric alcohols or a-hydrorycarboxylic acids. The mixture is then heated causiing formation of a bismuth hydroxide precipitate containing plutonium which may be readily dissolved in nitric acid for further processing.

  20. NREL: Measurements and Characterization - Minority-Carrier Lifetime...

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

    Photoluminescence Spectroscopy Minority-Carrier Lifetime Spectroscopy Fourier-Transform Infrared & Raman Spectroscopy Spectroscopic Ellipsometry Capacitance Techniques Scanning ...

  1. Carrier Density Modulation in Ge Heterostructure by Ferroelectric Switching

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

    Ponath, Patrick; Fredrickson, Kurt; Posadas, Agham B.; Ren, Yuan; Vasudevan, Rama K; Okatan, Mahmut Baris; Jesse, Stephen; Aoki, Toshihiro; McCartney, Martha; Smith, David J; et al

    2015-01-01

    The development of nonvolatile logic through direct coupling of spontaneous ferroelectric polarization with semiconductor charge carriers is nontrivial, with many issues, including epitaxial ferroelectric growth, demonstration of ferroelectric switching, and measurable semiconductor modulation. Here we report a true ferroelectric field effect carrier density modulation in an underlying Ge(001) substrate by switching of the ferroelectric polarization in the epitaxial c-axis-oriented BaTiO3 (BTO) grown by molecular beam epitaxy (MBE) on Ge. Using density functional theory, we demonstrate that switching of BTO polarization results in a large electric potential change in Ge. Aberration-corrected electron microscopy confirms the interface sharpness, and BTO tetragonality. Electron-energy-lossmore » spectroscopy (EELS) indicates the absence of any low permittivity interlayer at the interface with Ge. Using piezoelectric force microscopy (PFM), we confirm the presence of fully switchable, stable ferroelectric polarization in BTO that appears to be single domain. Using microwave impedance microscopy (MIM), we clearly demonstrate a ferroelectric field effect.« less

  2. Breach and safety analysis of spills over water from large liquefied natural gas carriers.

    SciTech Connect (OSTI)

    Hightower, Marion Michael; Luketa-Hanlin, Anay Josephine; Attaway, Stephen W.

    2008-05-01

    In 2004, at the request of the Department of Energy, Sandia National Laboratories (Sandia) prepared a report, ''Guidance on the Risk and Safety Analysis of Large Liquefied Natural Gas (LNG) Spills Over Water''. That report provided framework for assessing hazards and identifying approaches to minimize the consequences to people and property from an LNG spill over water. The report also presented the general scale of possible hazards from a spill from 125,000 m3 o 150,000 m3 class LNG carriers, at the time the most common LNG carrier capacity.

  3. PLUTONIUM PURIFICATION PROCESS EMPLOYING THORIUM PYROPHOSPHATE CARRIER

    DOE Patents [OSTI]

    King, E.L.

    1959-04-28

    The separation and purification of plutonium from the radioactive elements of lower atomic weight is described. The process of this invention comprises forming a 0.5 to 2 M aqueous acidffc solution containing plutonium fons in the tetravalent state and elements with which it is normally contaminated in neutron irradiated uranium, treating the solution with a double thorium compound and a soluble pyrophosphate compound (Na/sub 4/P/sub 2/O/sub 7/) whereby a carrier precipitate of thorium A method is presented of reducing neptunium and - trite is advantageous since it destroys any hydrazine f so that they can be removed from solutions in which they are contained is described. In the carrier precipitation process for the separation of plutonium from uranium and fission products including zirconium and columbium, the precipitated blsmuth phosphate carries some zirconium, columbium, and uranium impurities. According to the invention such impurities can be complexed and removed by dissolving the contaminated carrier precipitate in 10M nitric acid, followed by addition of fluosilicic acid to about 1M, diluting the solution to about 1M in nitric acid, and then adding phosphoric acid to re-precipitate bismuth phosphate carrying plutonium.

  4. Nonradiative coherent carrier captures and defect reaction at deep-level defects via phonon-kick mechanism

    SciTech Connect (OSTI)

    Wakita, Masaki; Suzuki, Kei; Shinozuka, Yuzo

    2014-02-21

    We simulated the time evolution of electron-lattice coupling mode, and a series of nonradiative carrier captures by a deep-level defect in a semiconductor. For lattice relaxation energy of the order of the band gap, a series of coherent (athermal) electron and hole captures by a defect is possible for high carrier densities, which results in an inflation in the induced lattice vibration, which in turn enhances a defect reaction.

  5. Energy

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

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

  6. Probing the carrier concentration profiles in phosphorus-implanted germanium using infrared spectroscopic ellipsometry

    SciTech Connect (OSTI)

    D'Costa, Vijay Richard Yeo, Yee-Chia

    2015-02-21

    Spectroscopic ellipsometry with photon energy in the 0.045–0.65 eV range was used to investigate germanium samples implanted with 30 keV phosphorus ions and annealed at 700 °C. The infrared response of implanted layers is dominated by free carrier absorption which is modeled using a Drude oscillator. The carrier concentration profiles were modeled using an error function, and compared with those obtained by electrochemical capacitance-voltage profiling and secondary ion mass spectrometry. In the flat region of the carrier concentration profile, average carrier concentration and mobility of 1.40 × 10{sup 19} cm{sup −3} and 336 cm{sup 2}V{sup −1}s{sup −1}, respectively, were obtained. A phosphorus diffusivity of ∼1.2 × 10{sup −13} cm{sup 2}/s was obtained. The mobility versus carrier concentration relationships obtained for the implanted samples are close to the empirical relationship for bulk Ge.

  7. Multiple pass laser amplifier system

    DOE Patents [OSTI]

    Brueckner, Keith A.; Jorna, Siebe; Moncur, N. Kent

    1977-01-01

    A laser amplification method for increasing the energy extraction efficiency from laser amplifiers while reducing the energy flux that passes through a flux limited system which includes apparatus for decomposing a linearly polarized light beam into multiple components, passing the components through an amplifier in delayed time sequence and recombining the amplified components into an in phase linearly polarized beam.

  8. Carrier quenching in InGaP/GaAs double heterostructures

    SciTech Connect (OSTI)

    Wells, Nathan P. Driskell, Travis U.; Hudson, Andrew I.; LaLumondiere, Stephen D.; Lotshaw, William T.; Forbes, David V.; Hubbard, Seth M.

    2015-08-14

    Photoluminescence measurements on a series of GaAs double heterostructures demonstrate a rapid quenching of carriers in the GaAs layer at irradiance levels below 0.1 W/cm{sup 2} in samples with a GaAs-on-InGaP interface. These results indicate the existence of non-radiative defect centers at or near the GaAs-on-InGaP interface, consistent with previous reports showing the intermixing of In and P when free As impinges on the InGaP surface during growth. At low irradiance, these defect centers can lead to sub-ns carrier lifetimes. The defect centers involved in the rapid carrier quenching can be saturated at higher irradiance levels and allow carrier lifetimes to reach hundreds of nanoseconds. To our knowledge, this is the first report of a nearly three orders of magnitude decrease in carrier lifetime at low irradiance in a simple double heterostructure. Carrier quenching occurs at irradiance levels near the integrated Air Mass Zero (AM0) and Air Mass 1.5 (AM1.5) solar irradiance. Additionally, a lower energy photoluminescence band is observed both at room and cryogenic temperatures. The temperature and time dependence of the lower energy luminescence is consistent with the presence of an unintentional InGaAs or InGaAsP quantum well that forms due to compositional mixing at the GaAs-on-InGaP interface. Our results are of general interest to the photovoltaic community as InGaP is commonly used as a window layer in GaAs based solar cells.

  9. Energy

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

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

  10. Energy

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

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

  11. Semiconductor Quantum Dots and Quantum Dot Arrays and Applications of Multiple Exciton Generation to Third-Generation Photovoltaic Solar Cells

    SciTech Connect (OSTI)

    Nozik, Arthur J.; Beard, Matthew C.; Luther, Joseph M.; Law, Matt; Ellingson, Randy J.; Johnson, Justin C.

    2010-10-14

    Here, we will first briefly summarize the general principles of QD synthesis using our previous work on InP as an example. Then we will focus on QDs of the IV-VI Pb chalcogenides (PbSe, PbS, and PbTe) and Si QDs because these were among the first QDs that were reported to produce multiple excitons upon absorbing single photons of appropriate energy (a process we call multiple exciton generation (MEG)). We note that in addition to Si and the Pb-VI QDs, two other semiconductor systems (III-V InP QDs(56) and II-VI core-shell CdTe/CdSe QDs(57)) were very recently reported to also produce MEG. Then we will discuss photogenerated carrier dynamics in QDs, including the issues and controversies related to the cooling of hot carriers and the magnitude and significance of MEG in QDs. Finally, we will discuss applications of QDs and QD arrays in novel quantum dot PV cells, where multiple exciton generation from single photons could yield significantly higher PV conversion efficiencies.

  12. Investigation of the {sup 208}Pb({sup 18}O, f) fission reaction: Mass-energy distributions of fission fragments and their correlation with the gamma-ray multiplicity

    SciTech Connect (OSTI)

    Rusanov, A. Ya.; Itkis, M. G.; Kondratiev, N. A.; Pashkevich, V. V.; Pokrovsky, I. V.; Salamatin, V. S.; Chubarian, G. G.

    2008-06-15

    The mass-energy distributions of fragments originating from the fission of the compound nucleus {sup 226}Th and their correlations with the multiplicity of gamma rays emitted from these fragments are measured and analyzed in {sup 18}O + {sup 208}Pb interaction induced by projectile oxygen ions of energy in the range E{sub lab} = 78-198.5 MeV. Manifestations of an asymmetric fission mode, which is damped exponentially with increasing E{sub lab}, are demonstrated. Theoretical calculations of fission valleys reveal that only two independent valleys, symmetric and asymmetric, exist in the vicinity of the scission point. The dependence of the multiplicity of gamma rays emitted from both fission fragments on their mass, M{sub {gamma}}(M), has a complicated structure and is highly sensitive to shell effects in both primary and final fragments. A two-component analysis of the dependence M{sub {gamma}}(M) shows that the asymmetric mode survives in fission only at low partial-wave orbital angular momenta of compound nuclei. It is found that, for all E{sub lab}, the gamma-ray multiplicity M{sub {gamma}}as a function of the total kinetic energy (TKE) of fragments, M{sub {gamma}}(TKE), decreases linearly with increasing TKE. An analysis of the energy balance in the fission process at the laboratory energy of E{sub lab} = 78 MeV revealed the region of cold fission of fragments whose total kinetic energy is TKE {approx}Q{sub max}.

  13. MEASUREMENT OF THE AVERAGE ENERGY AND MULTIPLICITY OF PROMPT-FISSION-NEUTRONS FROM 238U(n,f) AND 237 Np(n,f) FROM 1 TO 200 MeV.

    SciTech Connect (OSTI)

    TAIEB,J.; GRANIER, T.; ETHVIGNOT, T.; DEVLIN, M.; HAIGHT, R.C.; NELSON, R.O.; ODONNELL, J.M.; ROCHMAN, D.

    2007-06-28

    Taking advantage of the neutron source of the LANCSE, it has been possible to obtain a measure of the velocity distribution and the number of prompt-neutrons emitted in the neutron-induced fission of {sup 238}U and {sup 237}Np over a broad incident neutron energy range. The mean kinetic energy was extracted and is shown as the function of the incident-neutron energy. We confirm here the observation, for both reactions, of a dip around the second chance fission which is explained by the lower kinetic energy of the pre-fission neutrons. Such a observation is reproduced by Los Alamos model as implemented at Bruyeres le Chatel and by the Maslov model. As far as the neutron multiplicity is concerned, a similar dip is observed. However, such a behavior is not present in data measured by other groups.

  14. Synergetic effects of mixed copper-iron oxides oxygen carriers in chemical looping combustion

    SciTech Connect (OSTI)

    Siriwardane, Ranjani; Tian, Hanjing; Simonyi, Thomas; Poston, James

    2013-06-01

    Chemical looping combustion (CLC) is an emerging technology for clean energy production from fuels. CLC produces sequestration-ready CO{sub 2}-streams without a significant energy penalty. Development of efficient oxygen carriers is essential to successfully operate a CLC system. Copper and iron oxides are promising candidates for CLC. Copper oxide possesses high reactivity but it has issues with particle agglomeration due to its low melting point. Even though iron oxide is an inexpensive oxygen carrier it has a slower reactivity. In this study, mixed metal oxide carriers containing iron and copper oxides were evaluated for coal and methane CLC. The components of CuO and Fe{sub 2}O{sub 3} were optimized to obtain good reactivity while maintaining physical and chemical stability during cyclic reactions for methane-CLC and solid-fuel CLC. Compared with single metal oxygen carriers, the optimized Cu–Fe mixed oxide oxygen carriers demonstrated high reaction rate, better combustion conversion, greater oxygen usage and improved physical stability. Thermodynamic calculations, XRD, TGA, flow reactor studies and TPR experiments suggested that there is a strong interaction between CuO and Fe{sub 2}O{sub 3} contributing to a synergistic effect during CLC reactions. The amount of oxygen release of the mixed oxide carrier in the absence of a fuel was similar to that of the single metal oxides. However, in the presence of fuels, the oxygen consumption and the reaction profiles of the mixed oxide carriers were significantly better than that of the single metal oxides. The nature of the fuel not only influenced the reactivity, but also the final reduction status of the oxygen carriers during chemical looping combustion. Cu oxide of the mixed oxide was fully reduced metallic copper with both coal and methane. Fe oxide of the mixed oxide was fully reduced Fe metal with methane but it was reduced to only FeO with coal. Possible mechanisms of how the presence of CuO enhances the

  15. Photoinduced Spontaneous Free-Carrier Generation in Semiconducting Single-Walled Carbon Nanotubes

    SciTech Connect (OSTI)

    Park, Jaehong; Reid, Obadiah G.; Blackburn, Jeffrey L.; Rumbles, Garry

    2015-11-04

    The strong quantum confinement and low dielectric screening impart single-walled carbon nanotubes with exciton-binding energies substantially exceeding kBT at room temperature. Despite these large binding energies, reported photoluminescence quantum yields are typically low and some studies suggest that photoexcitation of carbon nanotube excitonic transitions can produce free charge carriers. Here we report the direct measurement of long-lived free-carrier generation in chirality-pure, single-walled carbon nanotubes in a low dielectric solvent. Time-resolved microwave conductivity enables contactless and quantitative measurement of the real and imaginary photoconductance of individually suspended nanotubes. We found that the conditions of the microwave conductivity measurement allow us to avoid the complications of most previous measurements of nanotube free-carrier generation, including tube–tube/tube–electrode contact, dielectric screening by nearby excitons and many-body interactions. At low photon fluence (approximately 0.05 excitons per μm length of tubes), we directly observe free carriers on excitation of the first and second carbon nanotube exciton transitions.

  16. Photoinduced Spontaneous Free-Carrier Generation in Semiconducting Single-Walled Carbon Nanotubes

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

    Park, Jaehong; Reid, Obadiah G.; Blackburn, Jeffrey L.; Rumbles, Garry

    2015-11-04

    The strong quantum confinement and low dielectric screening impart single-walled carbon nanotubes with exciton-binding energies substantially exceeding kBT at room temperature. Despite these large binding energies, reported photoluminescence quantum yields are typically low and some studies suggest that photoexcitation of carbon nanotube excitonic transitions can produce free charge carriers. Here we report the direct measurement of long-lived free-carrier generation in chirality-pure, single-walled carbon nanotubes in a low dielectric solvent. Time-resolved microwave conductivity enables contactless and quantitative measurement of the real and imaginary photoconductance of individually suspended nanotubes. We found that the conditions of the microwave conductivity measurement allow us tomore » avoid the complications of most previous measurements of nanotube free-carrier generation, including tube–tube/tube–electrode contact, dielectric screening by nearby excitons and many-body interactions. At low photon fluence (approximately 0.05 excitons per μm length of tubes), we directly observe free carriers on excitation of the first and second carbon nanotube exciton transitions.« less

  17. Alternative Carriers For Remote Renewable Energy Sources Using...

    Open Energy Info (EERE)

    the conversion of electricity to hydrogen, and then conversion of the hydrogen to methane. The paper also compares the alternative of direct injection of hydrogen into...

  18. Chemical Energy Carriers (CEC) for the Utilization of Geothermal...

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

    Center Development of Chemical Model to Predict the Interactions between Supercritical CO2and Fluid, and Rocks in EGS Reservoirs Automotive Thermoelectric Generators and HVAC

  19. Ultrafast photodetectors allow direct observation of multiple electrons

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

    generated by a single photon Ultrafast photodetectors Ultrafast photodetectors allow direct observation of multiple electrons generated by a single photon The new technique involves monitoring photocurrent transients in specially engineered photodetectors that provide very high temporal resolution of only 50 picoseconds. September 11, 2015 Andrew Fidler of Los Alamos National Laboratory examines an ultrafast photodetector used to measure quantum dot carrier multiplication in real time.

  20. Hydrogenation effects on carrier transport in boron-dopedultrananocry...

    Office of Scientific and Technical Information (OSTI)

    Hydrogenation effects on carrier transport in boron-doped ultrananocrystalline diamond... in boron-doped ultrananocrystalline diamondamorphous carbon films prepared by ...

  1. Suppress Carrier Recombination by Introducing Defects: The Case...

    Office of Scientific and Technical Information (OSTI)

    The Case of Si Solar Cell Citation Details In-Document Search Title: Suppress Carrier Recombination by Introducing Defects: The Case of Si Solar Cell Authors: Liu, Yuanyue ; ...

  2. Structure of the enzyme-acyl carrier protein (ACP) substrate...

    Office of Scientific and Technical Information (OSTI)

    complex required for biotin synthesis Citation Details In-Document Search Title: Structure of the enzyme-acyl carrier protein (ACP) substrate gatekeeper complex required ...

  3. Lattice and Carrier Dynamics in Quantum-Confined Materials on...

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

    We aim to characterize dissipation channels available to carriers via time-resolved optical spectroscopies. We utilize both femtosecond stimulated Raman spectroscopy (FSRS) and ...

  4. Profiling the local carrier concentration across a semiconductor...

    Office of Scientific and Technical Information (OSTI)

    Citation Details In-Document Search This content will become publicly available on May 11, 2016 Title: Profiling the local carrier concentration across a semiconductor quantum...

  5. Xcel Energy (Electric)- Business Energy Efficiency Rebate Programs

    Broader source: Energy.gov [DOE]

    Xcel Energy also offers design assistance for energy efficient buildings. Customers purchasing multiple energy efficient motors are now eligible for increased rebates. Xcel Energy also offers a...

  6. Hydrogen Fuel Cell Basics | Department of Energy

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

    is a versatile energy carrier that can be used to power nearly every end-use energy need. The fuel cell-an energy conversion device that can efficiently capture and use the power ...

  7. Hydrogen Production Basics | Department of Energy

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

    Hydrogen is an energy carrier, not an energy source-it stores and delivers energy in a usable form, but it must be produced from hydrogen containing compounds. Diverse and Domestic ...

  8. VIA OVERNIGHT MAIL CARRIER Mr. John D. Woolery President and Project Manager

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

    13, 2016 VIA OVERNIGHT MAIL CARRIER Mr. John D. Woolery President and Project Manager Portsmouth and Paducah DUF 6 Project BWXT Conversion Services, LLC 1020 Monarch Street Suite 300 Lexington, Kentucky 40513 WEA-2016-03 Dear Mr. Woolery: This letter refers to the Department of Energy's (DOE) investigation into the facts and circumstances associated with the March 25, 2015, potassium hydroxide (KOH) injury event at the Portsmouth DUF 6 Conversion Plant. The DOE Office of Enterprise Assessments'

  9. Multiple stage railgun

    DOE Patents [OSTI]

    Hawke, Ronald S.; Scudder, Jonathan K.; Aaland, Kristian

    1982-01-01

    A multiple stage magnetic railgun accelerator (10) for accelerating a projectile (15) by movement of a plasma arc (13) along the rails (11,12). The railgun (10) is divided into a plurality of successive rail stages (10a-n) which are sequentially energized by separate energy sources (14a-n) as the projectile (15) moves through the bore (17) of the railgun (10). Propagation of energy from an energized rail stage back towards the breech end (29) of the railgun (10) can be prevented by connection of the energy sources (14a-n) to the rails (11,12) through isolation diodes (34a-n). Propagation of energy from an energized rail stage back towards the breech end of the railgun can also be prevented by dividing the rails (11,12) into electrically isolated rail sections (11a-n, 12a-n). In such case means (55a-n) are used to extinguish the arc at the end of each energized stage and a fuse (31) or laser device (61) is used to initiate a new plasma arc in the next energized rail stage.

  10. ENERGY

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

    U.S. Department of ENERGY Department of Energy Quadrennial Technology Review-2015 Framing Document http:energy.govqtr 2015-01-13 Page 2 The United States faces serious ...

  11. Method for sintering fuel cell electrodes using a carrier

    DOE Patents [OSTI]

    Donelson, R.; Bryson, E.S.

    1995-03-28

    A carrier is described for conveying components of a fuel cell to be sintered through a sintering furnace. The carrier comprises a metal sheet coated with a carbon-based paint, the carbon-based paint comprising an organic binder. The carbon-based paint may be an alcohol or a solvent-based paint or a water-based paint.

  12. Coated metal sintering carriers for fuel cell electrodes

    DOE Patents [OSTI]

    Donelson, R.; Bryson, E.S.

    1998-11-10

    A carrier is described for conveying components of a fuel cell to be sintered through a sintering furnace. The carrier comprises a metal sheet coated with a water-based carbon paint, the water-based carbon paint comprising water, powdered graphite, an organic binder, a wetting agent, a dispersing agent and a defoaming agent.

  13. Method for sintering fuel cell electrodes using a carrier

    DOE Patents [OSTI]

    Donelson, Richard; Bryson, E. S.

    1995-01-01

    A carrier for conveying components of a fuel cell to be sintered through a sintering furnace. The carrier comprises a metal sheet coated with a carbon-based paint, the carbon-based paint comprising an organic binder. The carbon-based paint may be an alcohol or a solvent-based paint or a water-based paint.

  14. Coated metal sintering carriers for fuel cell electrodes

    DOE Patents [OSTI]

    Donelson, Richard (Glen Waverly, AU); Bryson, E. S. (Downers Grove, IL)

    1998-01-01

    A carrier for conveying components of a fuel cell to be sintered through a sintering furnace. The carrier comprises a metal sheet coated with a water-based carbon paint, the water-based carbon paint comprising water, powdered graphite, an organic binder, a wetting agent, a dispersing agent and a defoaming agent.

  15. Anisotropic charged impurity-limited carrier mobility in monolayer phosphorene

    SciTech Connect (OSTI)

    Ong, Zhun-Yong; Zhang, Gang; Zhang, Yong Wei

    2014-12-07

    The room temperature carrier mobility in atomically thin 2D materials is usually far below the intrinsic limit imposed by phonon scattering as a result of scattering by remote charged impurities in its environment. We simulate the charged impurity-limited carrier mobility μ in bare and encapsulated monolayer phosphorene. We find a significant temperature dependence in the carrier mobilities (μ ∝ T{sup −γ}) that results from the temperature variability of the charge screening and varies with the crystal orientation. The anisotropy in the effective mass leads to an anisotropic carrier mobility, with the mobility in the armchair direction about one order of magnitude larger than in the zigzag direction. In particular, this mobility anisotropy is enhanced at low temperatures and high carrier densities. Under encapsulation with a high-κ overlayer, the mobility increases by up to an order of magnitude although its temperature dependence and its anisotropy are reduced.

  16. Metal-Organic Heat Carrier Nanofluids

    SciTech Connect (OSTI)

    McGrail, B. Peter; Thallapally, Praveen K.; Blanchard, Jeremy; Nune, Satish K.; Jenks, Jeromy WJ; Dang, Liem X.

    2013-09-01

    Nanofluids, dispersions of metal or oxide nanoparticles in a base working fluid, are being intensively studied due to improvements they offer in thermal properties of the working fluid. However, these benefits have been erratically demonstrated and proven impacts on thermal conductivity are modest and well described from long-established effective medium theory. In this paper, we describe a new class of metal-organic heat carrier (MOHC) nanofluid that offers potential for a larger performance boost in thermal vapor-liquid compression cycles. MOHCs are nanophase porous coordination solids designed to reversibly uptake the working fluid molecules in which the MOHCs are suspended. Additional heat can be extracted in a heat exchanger or solar collector from the endothermic enthalpy of desorption, which is then released as the nanofluid transits through a power generating device such as a turboexpander. Calculations for an R123 MOHC nanofluid indicated potential for up to 15% increase in power output. Capillary tube experiments show that liquid-vapor transitions occur without nanoparticle deposition on the tube walls provided entrance Reynolds number exceeds approximately 100.

  17. British Columbia: Energy Resources | Open Energy Information

    Open Energy Info (EERE)

    Incentives for British Columbia Energy Monitoring Act (Canada) Western Interstate Nuclear Compact State Nuclear Policy (Multiple States) References http:...

  18. Efficient carrier relaxation and fast carrier recombination of N-polar InGaN/GaN light emitting diodes

    SciTech Connect (OSTI)

    Feng, Shih-Wei Liao, Po-Hsun; Leung, Benjamin; Han, Jung; Yang, Fann-Wei; Wang, Hsiang-Chen

    2015-07-28

    Based on quantum efficiency and time-resolved electroluminescence measurements, the effects of carrier localization and quantum-confined Stark effect (QCSE) on carrier transport and recombination dynamics of Ga- and N-polar InGaN/GaN light-emitting diodes (LEDs) are reported. The N-polar LED exhibits shorter ns-scale response, rising, delay, and recombination times than the Ga-polar one does. Stronger carrier localization and the combined effects of suppressed QCSE and electric field and lower potential barrier acting upon the forward bias in an N-polar LED provide the advantages of more efficient carrier relaxation and faster carrier recombination. By optimizing growth conditions to enhance the radiative recombination, the advantages of more efficient carrier relaxation and faster carrier recombination in a competitive performance N-polar LED can be realized for applications of high-speed flash LEDs. The research results provide important information for carrier transport and recombination dynamics of an N-polar InGaN/GaN LED.

  19. Experimental and computational results on exciton/free-carrier ratio, hot/thermalized carrier diffusion, and linear/nonlinear rate constants affecting scintillator proportionality

    SciTech Connect (OSTI)

    Williams, Richard; Grim, Joel; Li, Qi; Ucer, K. B.; Bizarri, G. A.; Kerisit, Sebastien N.; Gao, Fei; Bhattacharya, Pijush; Tupitsyn, Eugene; Rowe, Emmanuel; Buliga, Vladimir M.; Burger, Arnold

    2013-10-01

    Models of nonproportional response in scintillators have highlighted the importance of parameters such as branching ratios, carrier thermalization times, diffusion, kinetic order of quenching, associated rate constants, and radius of the electron track. For example, the fraction ηeh of excitations that are free carriers versus excitons was shown by Payne and coworkers to have strong correlation with the shape of electron energy response curves from Compton-coincidence studies. Rate constants for nonlinear quenching are implicit in almost all models of nonproportionality, and some assumption about track radius must invariably be made if one is to relate linear energy deposition dE/dx to volume-based excitation density n (eh/cm3) in terms of which the rates are defined. Diffusion, affecting time-dependent track radius and thus density of excitations, has been implicated as an important factor in nonlinear light yield. Several groups have recently highlighted diffusion of hot electrons in addition to thermalized carriers and excitons in scintillators. However, experimental determination of many of these parameters in the insulating crystals used as scintillators has seemed difficult. Subpicosecond laser techniques including interband z scan light yield, fluence-dependent decay time, and transient optical absorption are now yielding experimental values for some of the missing rates and ratios needed for modeling scintillator response. First principles calculations and Monte Carlo simulations can fill in additional parameters still unavailable from experiment. As a result, quantitative modeling of scintillator electron energy response from independently determined material parameters is becoming possible on an increasingly firmer data base. This paper describes recent laser experiments, calculations, and numerical modeling of scintillator response.

  20. Test Procedures for Building Energy Simulation Tools | Department of Energy

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

    Test Procedures for Building Energy Simulation Tools Test Procedures for Building Energy Simulation Tools Lead Performer: -- National Renewable Energy Laboratory - Golden, CO -- J. Neymark & Associates - Golden, CO -- Lawrence Berkeley National Laboratory (LBNL) - Berkeley, CA Partners: -- ASHRAE Standing Special Projects Committee 140 -- Residential Energy Services Network (RESNET) -- International Energy Agency (IEA) - Paris, France -- Trane Inc. - Piscataway, NJ -- Carrier Corp. -

  1. Energy

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

    Energy Energy National security depends on science and technology. The United States relies on Los Alamos National Laboratory for the best of both. No place on Earth pursues a broader array of world-class scientific endeavors. Energy Overview Charlie McMillan, Director of Los Alamos National Laboratory 0:50 Director McMillan on energy security With energy use increasing across the nation and the world, Los Alamos National Laboratory is using its world-class scientific capabilities to enhance

  2. Longitudinal review of state-level accident statistics for carriers of interstate freight

    SciTech Connect (OSTI)

    Saricks, C.; Kvitek, T.

    1994-03-01

    State-level accident rates by mode of freight transport have been developed and refined for application to the US Department of Energy`s (DOE`s) environmental mitigation program, which may involve large-quantity shipments of hazardous and mixed wastes from DOE facilities. These rates reflect multi-year data for interstate-registered highway earners, American Association of Railroads member carriers, and coastal and internal waterway barge traffic. Adjustments have been made to account for the share of highway combination-truck traffic actually attributable to interstate-registered carriers and for duplicate or otherwise inaccurate entries in the public-use accident data files used. State-to-state variation in rates is discussed, as is the stability of rates over time. Computed highway rates have been verified with actual carriers of high- and low-level nuclear materials, and the most recent truck accident data have been used, to ensure that the results are of the correct order of magnitude. Study conclusions suggest that DOE use the computed rates for the three modes until (1) improved estimation techniques for highway combination-truck miles by state become available; (2) continued evolution of the railroad industry significantly increases the consolidation of interstate rail traffic onto fewer high-capacity trunk lines; or (3) a large-scale off-site waste shipment campaign is imminent.

  3. Growth kinetics of CVD TiO sub 2; Influence of carrier gas

    SciTech Connect (OSTI)

    Siefering, K.L.; Griffin, G.L. )

    1990-04-01

    This paper reports on the growth rate of TiO{sub 2} thin films deposited by the decomposition of titanium tetraisopropoxide (TTIP) in the presence of N{sub 2} carrier gas. Experiments are performed at TTIP partial pressures between 0.005 and 0.7 torr and a substrate temperature of 573 K, conditions where second-order kinetics have previously been observed in the presence of TTIP alone. When 5 torr of N{sub 2} is present as a carrier gas, the kinetics become first order in TTIP concentration. By fitting the observed rates to the rate expression for the bimolecular reaction mechanism proposed in the earlier study, the authors obtain a value of {phi} = 0.43 for the relative efficiency of N{sub 2} for collisional energy transfer, compared to TTIP.

  4. Effect of temperature on carrier formation efficiency in organic photovoltaic cells

    SciTech Connect (OSTI)

    Moritomo, Yutaka Yonezawa, Kouhei; Yasuda, Takeshi

    2014-08-18

    The internal quantum efficiency (?{sub IQ}) of an organic photovoltaic cell is governed by plural processes. Here, we propose that ?{sub IQ} can be experimentally decomposed into carrier formation (?{sub CF}) and carrier transfer (?{sub CT}) efficiencies. By combining femtosecond time-resolved and electrochemical spectroscopy, we clarified the effect of temperature on ?{sub CF} in a regioregular poly(3-hexylthiophene) (rr-P3HT)/[6,6]-phenyl C{sub 61}-butyric acid methyl ester blend film. We found that ?{sub CF}?(=0.55) at 80?K is the same as that (=0.55) at 300?K. The temperature insensitivity of ?{sub CF} indicates that the electron-hole pairs at the D/A interface are seldom subjected to coulombic binding energy.

  5. Ocean thermal plantships for production of ammonia as the hydrogen carrier.

    SciTech Connect (OSTI)

    Panchal, C.B.; Pandolfini, P. P.; Kumm, W. H.; Energy Systems; Johns Hopkins Univ.; Arctic Energies, Ltd.

    2009-12-02

    Conventional petroleum, natural gas, and coal are the primary sources of energy that have underpinned modern civilization. Their continued availability in the projected quantities required and the impacts of emission of greenhouse gases (GHGs) on the environment are issues at the forefront of world concerns. New primary sources of energy are being sought that would significantly reduce the emissions of GHGs. One such primary source that can help supply energy, water, and fertilizer without GHG emissions is available in the heretofore unexploited thermal gradients of the tropical oceans. The world's oceans are the largest natural collector and reservoir of solar energy. The potential of ocean energy is limitless for producing base-load electric power or ammonia as the hydrogen carrier and fresh water from seawater. However, until now, ocean energy has been virtually untapped. The general perception is that ocean thermal energy is limited to tropical countries. Therefore, the full potential of at-sea production of (1) ammonia as a hydrogen carrier and (2) desalinated water has not been adequately evaluated. Using ocean thermal plantships for the at-sea co-production of ammonia as a hydrogen carrier and desalinated water offer potential energy, environmental, and economic benefits that support the development of the technology. The introduction of a new widespread solution to our projected energy supply requires lead times of a decade or more. Although continuation of the ocean thermal program from the 1970s would likely have put us in a mitigating position in the early 2000s, we still have a window of opportunity to dedicate some of our conventional energy sources to the development of this renewable energy by the time new sources would be critically needed. The primary objective of this project is to evaluate the technical and economic viability of ocean thermal plantships for the production of ammonia as the hydrogen carrier. This objective is achieved by

  6. Charge carrier effective mass and concentration derived from combination of Seebeck coefficient and Te125 NMR measurements in complex tellurides

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

    Levin, E. M.

    2016-06-27

    Thermoelectric materials utilize the Seebeck effect to convert heat to electrical energy. The Seebeck coefficient (thermopower), S, depends on the free (mobile) carrier concentration, n, and effective mass, m*, as S ~ m*/n2/3. The carrier concentration in tellurides can be derived from 125Te nuclear magnetic resonance (NMR) spin-lattice relaxation measurements. The NMR spin-lattice relaxation rate, 1/T1, depends on both n and m* as 1/T1~(m*)3/2n (within classical Maxwell-Boltzmann statistics) or as 1/T1~(m*)2n2/3 (within quantum Fermi-Dirac statistics), which challenges the correct determination of the carrier concentration in some materials by NMR. Here it is shown that the combination of the Seebeck coefficientmore » and 125Te NMR spin-lattice relaxation measurements in complex tellurides provides a unique opportunity to derive the carrier effective mass and then to calculate the carrier concentration. This approach was used to study AgxSbxGe50–2xTe50, well-known GeTe-based high-efficiency tellurium-antimony-germanium-silver thermoelectric materials, where the replacement of Ge by [Ag+Sb] results in significant enhancement of the Seebeck coefficient. Thus, values of both m* and n derived using this combination show that the enhancement of thermopower can be attributed primarily to an increase of the carrier effective mass and partially to a decrease of the carrier concentration when the [Ag+Sb] content increases.« less

  7. Carrier-induced transient defect mechanism for non-radiative recombination in InGaN light-emitting devices

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

    Bang, Junhyeok; Sun, Y. Y.; Song, Jung -Hoon; Zhang, S. B.

    2016-04-14

    Non-radiative recombination (NRR) of excited carriers poses a serious challenge to optoelectronic device efficiency. Understanding the mechanism is thus crucial to defect physics and technological applications. Here, by using first-principles calculations, we propose a new NRR mechanism, where excited carriers recombine via a Frenkel-pair (FP) defect formation. While in the ground state the FP is high in energy and is unlikely to form, in the electronic excited states its formation is enabled by a strong electron-phonon coupling of the excited carriers. As a result, this NRR mechanism is expected to be general for wide-gap semiconductors, rather than being limited tomore » InGaN-based light emitting devices.« less

  8. Injection deep level transient spectroscopy: An improved method for measuring capture rates of hot carriers in semiconductors

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

    Fleming, R. M.; Seager, C. H.; Lang, D. V.; Campbell, J. M.

    2015-07-02

    In this study, an improved method for measuring the cross sections for carrier trapping at defects in semiconductors is described. This method, a variation of deep level transient spectroscopy(DLTS) used with bipolar transistors, is applied to hot carrier trapping at vacancy-oxygen, carbon-oxygen, and three charge states of divacancy centers (V2) in n- and p-type silicon. Unlike standard DLTS, we fill traps by injecting carriers into the depletion region of a bipolar transistor diode using a pulse of forward bias current applied to the adjacent diode. We show that this technique is capable of accurately measuring a wide range of capturemore » cross sections at varying electric fields due to the control of the carrier density it provides. Because this technique can be applied to a variety of carrier energy distributions, it should be valuable in modeling the effect of radiation-induced generation-recombination currents in bipolar devices.« less

  9. Improvement in carrier transport properties by mild thermal annealing...

    Office of Scientific and Technical Information (OSTI)

    quantum dot solar cells Citation Details In-Document Search Title: Improvement in carrier transport properties by mild thermal annealing of PbS quantum dot solar cells Authors: ...

  10. Charge carrier coherence and Hall effect in organic semiconductors

    Office of Scientific and Technical Information (OSTI)

    OPEN: Charge carrier coherence and Hall effect in organic semiconductors H. T. Yi1, Y. N. Gartstein2 & V. Podzorov1-3 Received: 21 January 2016 Accepted: 29 February 2016 ...

  11. Bimetallic Fe-Ni Oxygen Carriers for Chemical Looping Combustion

    SciTech Connect (OSTI)

    Bhavsar, Saurabh; Veser, Goetz

    2013-11-06

    The relative abundance, low cost, and low toxicity of iron make Fe-based oxygen carriers of great interest for chemical looping combustion (CLC), an emerging technology for clean and efficient combustion of fossil and renewable fuels. However, Fe also shows much lower reactivity than other metals (such as Ni and Cu). Here, we demonstrate strong improvement of Fe-based carriers by alloying the metal phase with Ni. Through a combination of carrier synthesis and characterization with thermogravimetric and fixed-bed reactor studies, we demonstrate that the addition of Ni results in a significant enhancement in activity as well as an increase in selectivity for total oxidation. Furthermore, comparing alumina and ceria as support materials highlights the fact that reducible supports can result in a strong increase in oxygen carrier utilization.

  12. Mobility of charge carriers in porous silicon layers

    SciTech Connect (OSTI)

    Forsh, P. A. Martyshov, M. N.; Latysheva, A. P.; Vorontsov, A. S.; Timoshenko, V. Yu.; Kashkarov, P. K.

    2008-12-15

    The (conduction) mobility of majority charge carriers in porous silicon layers of the n and p types is estimated by joint measurements of electrical conductivity and free charge carrier concentration, which is determined from IR absorption spectra. Adsorption of donor and acceptor molecules leading to a change in local electric fields in the structure is used to identify the processes controlling the mobility in porous silicon. It is found that adsorption of acceptor and donor molecules at porous silicon of the p and n types, respectively, leads to a strong increase in electrical conductivity, which is associated with an increase in the concentration of free carrier as well as in their mobility. The increase in the mobility of charge carriers as a result of adsorption indicates the key role of potential barriers at the boundaries of silicon nanocrystals and may be due to a decrease in the barrier height as a result of adsorption.

  13. Test probe for surface mounted leadless chip carrier

    DOE Patents [OSTI]

    Meyer, Kerry L.; Topolewski, John

    1989-05-23

    A test probe for a surface mounted leadless chip carrier is disclosed. The probed includes specially designed connector pins which allow size reductions in the probe. A thermoplastic housing provides spring action to ensure good mechanical and electrical contact between the pins and the contact strips of a leadless chip carrier. Other features include flexible wires molded into the housing and two different types of pins alternately placed in the housing. These features allow fabrication of a smaller and simpler test probe.

  14. Three-dimensional transient model for time-domain free-carrier absorption measurement of excess carriers in silicon wafers

    SciTech Connect (OSTI)

    Ren, Shengdong; Huang, Qiuping; Li, Bincheng

    2013-12-28

    A three-dimensional transient model for time-domain (modulated) free-carrier absorption (FCA) measurement was developed to describe the transport dynamics of photo-generated excess carriers in silicon (Si) wafers. With the developed transient model, numerical simulations were performed to investigate the dependences of the waveforms of the transient FCA signals on the electronic transport parameters of Si wafers and the geometric parameters of the FCA experiment. Experimental waveforms of FCA signals of both n- and p-type Si wafers with resistivity ranging 1–38 Ω·cm were then fitted to the three-dimensional transient model to extract simultaneously and unambiguously the transport parameters of Si wafers, namely, the carrier lifetime, the carrier diffusion coefficient, and the front surface recombination velocity via multi-parameter fitting. A basic agreement between the extracted parameter values and the literature values was obtained.

  15. The Global Energy Challenge (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    sunlight, and heat to electricity or hydrogen as an energy carrier and finally to end ... Country of Publication: United States Language: English Subject: 08 HYDROGEN; ...

  16. The Global Energy Challenge (Conference) | SciTech Connect

    Office of Scientific and Technical Information (OSTI)

    sunlight, and heat to electricity or hydrogen as an energy carrier and finally to end ... Science (SC) Country of Publication: United States Language: English Subject: 08 HYDROGEN

  17. Production Costs of Alternative Transportation Fuels | Open Energy...

    Open Energy Info (EERE)

    ... further results Find Another Tool FIND TRANSPORTATION TOOLS This study examines the production costs of a range of transport fuels and energy carriers under varying crude oil...

  18. To: John Cymbalsky, United States Department of Energy From:...

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

    Amy Shepherd AHRI Rodney Sobin Alliance to Save Energy Louis Starr NEEA Rusty Tharp Goodman Meg Waltner NRDC Detlef Westphalen Navigant Consulting, Inc. Robert Whitwell Carrier ...

  19. Department of Energy Announces Selection of Transportation Contractors...

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

    Department of Energy Announces Selection of Transportation Contractors at the Waste ... TSMT, based in Joplin, MO, is a nationwide carrier with experience hauling hazardous and ...

  20. EA-1976: Final Environmental Assessment | Department of Energy

    Office of Environmental Management (EM)

    Emera CNG, LLC Compressed Natural Gas Project, Florida DOE's National Energy Technology ... tank containers, and ocean-going carrier for export through the Port of Palm Beach. ...

  1. Energy Department Announces $150 Million in Tax Credits to Invest...

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

    ... These projects, subject to final certification, include following: Energy Efficient Buildings: With the support of 5.1 million in 48C Program tax credits, Carrier Corporation will ...

  2. Welcome - Center for Solar and Thermal Energy Conversion

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

    To Bridge LEDs' Green Gap, Scientists Think Small ... Really Small Read about CSTEC's latest Research Energy Transport in Organic and Hybrid Systems Absorption and Carrier ...

  3. Energy

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

    Energy Energy Research into alternative forms of energy, and improving and securing the power grid, is a major national security imperative. News Releases Science Briefs Photos Picture of the Week Publications Social Media Videos Fact Sheets Pajarito Powder, LLC, a fuel-cell-catalyst company based in Albuquerque, is one of the voucher recipients that will partner with Los Alamos. Fuel-cell technology companies win small-business aid Pajarito Powder, LLC, (Albuquerque), NanoSonic (Pembroke, Va.)

  4. Energy

    Office of Legacy Management (LM)

    ..) ".. _,; ,' . ' , ,; Depar?.me.nt ,of.' Energy Washington; DC 20585 : . ' , - $$ o"\ ' ~' ,' DEC ?;$ ;y4,,, ~ ' .~ The Honorable John Kalwitz , 200 E. Wells Street Milwaukee, W~isconsin 53202, . . i :. Dear,Mayor 'Kalwitz: " . " Secretary of Energy Hazel' O'Leary has announceha new,approach 'to,openness in " the Department of Ene~rgy (DOE) and its communications with'the public. In -. support of~this initiative, we areipleased to forward the enclosed information

  5. Electronic properties and carrier mobilities of 6,6,12-graphyne nanoribbons

    SciTech Connect (OSTI)

    Ding, Heyu; Huang, Yuanhe; Bai, Hongcun

    2015-07-15

    Structures, stabilities, electronic properties and carrier mobilities of 6,6,12-graphyne nanoribbons (GyNRs) with armchair and zigzag edges are investigated using the self-consistent field crystal orbital method based on density functional theory. It is found that the 1D GyNRs are more stable than the 2D 6,6,12-graphyne sheet in the view of the Gibbs free energy. The stabilities of these GyNRs decrease as their widths increase. The calculated band structures show that all these GyNRs are semiconductors and that dependence of band gaps on the ribbon width is different from different types of the GyNRs. The carrier mobility was calculated based on the deformation theory and effective mass approach. It is found that the carrier mobilities of these GyNRs can reach the order of 10{sup 5} cm{sup 2} V {sup –1}s{sup –1} at room temperature and are comparable to those of graphene NRs. Moreover, change of the mobilities with change of the ribbon width is quite different from different types of the GyNRs.

  6. Multiple target laser ablation system

    DOE Patents [OSTI]

    Mashburn, D.N.

    1996-01-09

    A laser ablation apparatus and method are provided in which multiple targets consisting of material to be ablated are mounted on a movable support. The material transfer rate is determined for each target material, and these rates are stored in a controller. A position detector determines which target material is in a position to be ablated, and then the controller controls the beam trigger timing and energy level to achieve a desired proportion of each constituent material in the resulting film. 3 figs.

  7. Multiple target laser ablation system

    DOE Patents [OSTI]

    Mashburn, Douglas N.

    1996-01-01

    A laser ablation apparatus and method are provided in which multiple targets consisting of material to be ablated are mounted on a movable support. The material transfer rate is determined for each target material, and these rates are stored in a controller. A position detector determines which target material is in a position to be ablated, and then the controller controls the beam trigger timing and energy level to achieve a desired proportion of each constituent material in the resulting film.

  8. Hyperfine-induced spin relaxation of a diffusively moving carrier in low dimensions: Implications for spin transport in organic semiconductors

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

    Mkhitaryan, V. V.; Dobrovitski, V. V.

    2015-08-24

    The hyperfine coupling between the spin of a charge carrier and the nuclear spin bath is a predominant channel for the carrier spin relaxation in many organic semiconductors. We theoretically investigate the hyperfine-induced spin relaxation of a carrier performing a random walk on a d-dimensional regular lattice, in a transport regime typical for organic semiconductors. We show that in d=1 and 2, the time dependence of the space-integrated spin polarization P(t) is dominated by a superexponential decay, crossing over to a stretched-exponential tail at long times. The faster decay is attributed to multiple self-intersections (returns) of the random-walk trajectories, whichmore » occur more often in lower dimensions. We also show, analytically and numerically, that the returns lead to sensitivity of P(t) to external electric and magnetic fields, and this sensitivity strongly depends on dimensionality of the system (d=1 versus d=3). We investigate in detail the coordinate dependence of the time-integrated spin polarization σ(r), which can be probed in the spin-transport experiments with spin-polarized electrodes. We also demonstrate that, while σ(r) is essentially exponential, the effect of multiple self-intersections can be identified in transport measurements from the strong dependence of the spin-decay length on the external magnetic and electric fields.« less

  9. Hyperfine-induced spin relaxation of a diffusively moving carrier in low dimensions: Implications for spin transport in organic semiconductors

    SciTech Connect (OSTI)

    Mkhitaryan, V. V.; Dobrovitski, V. V.

    2015-08-24

    The hyperfine coupling between the spin of a charge carrier and the nuclear spin bath is a predominant channel for the carrier spin relaxation in many organic semiconductors. We theoretically investigate the hyperfine-induced spin relaxation of a carrier performing a random walk on a d-dimensional regular lattice, in a transport regime typical for organic semiconductors. We show that in d=1 and 2, the time dependence of the space-integrated spin polarization P(t) is dominated by a superexponential decay, crossing over to a stretched-exponential tail at long times. The faster decay is attributed to multiple self-intersections (returns) of the random-walk trajectories, which occur more often in lower dimensions. We also show, analytically and numerically, that the returns lead to sensitivity of P(t) to external electric and magnetic fields, and this sensitivity strongly depends on dimensionality of the system (d=1 versus d=3). We investigate in detail the coordinate dependence of the time-integrated spin polarization σ(r), which can be probed in the spin-transport experiments with spin-polarized electrodes. We also demonstrate that, while σ(r) is essentially exponential, the effect of multiple self-intersections can be identified in transport measurements from the strong dependence of the spin-decay length on the external magnetic and electric fields.

  10. Effect of carrier recombination on ultrafast carrier dynamics in thin films of the topological insulator Bi{sub 2}Se{sub 3}

    SciTech Connect (OSTI)

    Glinka, Yuri D.; Babakiray, Sercan; Johnson, Trent A.; Holcomb, Mikel B.; Lederman, David

    2014-10-27

    Transient reflectivity (TR) from thin films (6–40 nm thick) of the topological insulator Bi{sub 2}Se{sub 3} revealed ultrafast carrier dynamics, which suggest the existence of both radiative and non-radiative recombination between electrons residing in the upper cone of initially unoccupied high energy Dirac surface states (SS) and holes residing in the lower cone of occupied low energy Dirac SS. The modeling of measured TR traces allowed us to conclude that recombination is induced by the depletion of bulk electrons in films below ∼20 nm thick due to the charge captured on the surface defects. We predict that such recombination processes can be observed using time-resolved photoluminescence techniques.

  11. Effect of charge trapping on effective carrier lifetime in compound semiconductors: High resistivity CdZnTe

    SciTech Connect (OSTI)

    Kamieniecki, Emil

    2014-11-21

    The dominant problem limiting the energy resolution of compound semiconductor based radiation detectors is the trapping of charge carriers. The charge trapping affects energy resolution through the carrier lifetime more than through the mobility. Conventionally, the effective carrier lifetime is determined using a 2-step process based on measurement of the mobility-lifetime product (μτ) and determining drift mobility using time-of-flight measurements. This approach requires fabrication of contacts on the sample. A new RF-based pulse rise-time method, which replaces this 2-step process with a single non-contact direct measurement, is discussed. The application of the RF method is illustrated with high-resistivity detector-grade CdZnTe crystals. The carrier lifetime in the measured CdZnTe, depending on the quality of the crystals, was between about 5 μs and 8 μs. These values are in good agreement with the results obtained using conventional 2-step approach. While the effective carrier lifetime determined from the initial portion of the photoresponse transient combines both recombination and trapping in a manner similar to the conventional 2-step approach, both the conventional and the non-contact RF methods offer only indirect evaluation of the effect of charge trapping in the semiconductors used in radiation detectors. Since degradation of detector resolution is associated not with trapping but essentially with detrapping of carriers, and, in particular, detrapping of holes in n-type semiconductors, it is concluded that evaluation of recombination and detrapping during photoresponse decay is better suited for evaluation of compound semiconductors used in radiation detectors. Furthermore, based on previously reported data, it is concluded that photoresponse decay in high resistivity CdZnTe at room temperature is dominated by detrapping of carriers from the states associated with one type of point defect and by recombination of carriers at one type of

  12. Modulation of hole-injection in GaInN-light emitting triodes and its effect on carrier recombination behavior

    SciTech Connect (OSTI)

    Hwang, Sunyong; Kim, Dong Yeong; Park, Jun Hyuk; Kim, Jong Kyu; Ryu, Han-Youl

    2015-10-15

    The effects of the hole injection modulated by using a three-terminal GaInN-based light emitter, light-emitting triode (LET), on carrier recombination behavior and efficiency droop are investigated. It was found that the lateral electric field created by applying voltage bias between the two anodes effectively reduces efficiency droop as well as dynamic conductance of LETs. Detailed analyses of LETs under various operation conditions by APSYS simulations reveal that the asymmetry in carrier transport between electrons and holes is alleviated by promoted injection of hot holes over the potential barrier, increasing the hole concentration as well as the radiative recombination rate in the multiple quantum well active region.

  13. VIA OVERNIGHT UPS MAIL CARRIER Dr. Charles F. McMillan, President

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

    8, 2016 VIA OVERNIGHT UPS MAIL CARRIER Dr. Charles F. McMillan, President Los Alamos National Security, LLC Los Alamos National Laboratory Mailstop A 100, Drop Point 03140071S Bikini Atoll Road, TA-3 Los Alamos, New Mexico 87545-1663 WEA-2016-02 Dear Dr. McMillan: This letter refers to the Department of Energy's (DOE) investigation into the facts and circumstances associated with the implementation of the Los Alamos National Laboratory (LANL) electrical safety program as evidenced by a series of

  14. Intensity- and temperature- dependent carrier recombination in InAs/In(As1-xSbx) type-II superlattices

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

    Olson, Benjamin Varberg; Kadlec, Emil Andrew; Kim, Jin K.; Klem, John F.; Hawkins, Samuel D.; Shaner, Eric A.; Flatte, Michael E.

    2015-04-17

    Our time-resolved measurements for carrier recombination are reported as a midwave infrared InAs/InAs0.66Sb0.34 type-II superlattice (T2SL) function of pump intensity and sample temperature. By including the T2SL doping level in the analysis, the Shockley-Read-Hall (SRH), radiative, and Auger recombination components of the carrier lifetime are uniquely distinguished at each temperature. SRH is the limiting recombination mechanism for excess carrier densities less than the doping level (the low-injection regime) and temperatures less than 175 K. A SRH defect energy of 95 meV, either below the T2SL conduction-band edge or above the T2SL valence-band edge, is identified. Auger recombination limits the carriermore » lifetimes for excess carrier densities greater than the doping level (the high-injection regime) for all temperatures tested. Additionally, at temperatures greater than 225 K, Auger recombination also limits the low-injection carrier lifetime due to the onset of the intrinsic temperature range and large intrinsic carrier densities. Radiative recombination is found to not have a significant contribution to the total lifetime for all temperatures and injection regimes, with the data implying a photon recycling factor of 15. Using the measured lifetime data, diffusion currents are calculated and compared to calculated Hg1-xCdxTe dark current, indicating that the T2SL can have a lower dark current with mitigation of the SRH defect states. Our results illustrate the potential for InAs/InAs1-xSbx T2SLs as absorbers in infrared photodetectors.« less

  15. Mechanisms of Carrier Transport Induced by a Microswimmer Bath

    SciTech Connect (OSTI)

    Kaiser, Andreas; Sokolov, Andrey; Aranson, Igor S.; Lowen, Hartmut

    2015-04-01

    Recently, it was found that a wedgelike microparticle (referred to as ”carrier”) which is only allowed to translate but not to rotate exhibits a directed translational motion along the wedge cusp if it is exposed to a bath of microswimmers. Here we model this effect in detail by resolving the microswimmers explicitly using interaction models with different degrees of mutual alignment. Using computer simulations we study the impact of these interactions on the transport efficiency of V-shaped carrier. We show that the transport mechanisms itself strongly depends on the degree of alignment embodied in the modelling of the individual swimmer dynamics. For weak alignment, optimal carrier transport occurs in the turbulent microswimmer state and is induced by swirl depletion inside the carrier. For strong aligning interactions, optimal transport occurs already in the dilute regime and is mediated by a polar cloud of swimmers in the carrier wake pushing the wedge-particle forward. We also demonstrate that the optimal shape of the carrier leading to maximal transport speed depends on the kind of interaction model used.

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

    SciTech Connect (OSTI)

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

    2014-08-14

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

  17. Charge carrier coherence and Hall effect in organic semiconductors

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

    Yi, H. T.; Gartstein, Y. N.; Podzorov, V.

    2016-03-30

    Hall effect measurements are important for elucidating the fundamental charge transport mechanisms and intrinsic mobility in organic semiconductors. However, Hall effect studies frequently reveal an unconventional behavior that cannot be readily explained with the simple band-semiconductor Hall effect model. Here, we develop an analytical model of Hall effect in organic field-effect transistors in a regime of coexisting band and hopping carriers. The model, which is supported by the experiments, is based on a partial Hall voltage compensation effect, occurring because hopping carriers respond to the transverse Hall electric field and drift in the direction opposite to the Lorentz force actingmore » on band carriers. We show that this can lead in particular to an underdeveloped Hall effect observed in organic semiconductors with substantial off-diagonal thermal disorder. Lastly, our model captures the main features of Hall effect in a variety of organic semiconductors and provides an analytical description of Hall mobility, carrier density and carrier coherence factor.« less

  18. Energy

    Annual Energy Outlook [U.S. Energy Information Administration (EIA)]

    M onthly Energy Re< view Ila A a m 0 II 8 IIIW *g U In this issue: New data on nuclear electricity in Eastern Europe (Table 10.4) 9'Ij a - Ordering Information This publication...

  19. Method of immobilizing water-soluble bioorganic compounds on a capillary-porous carrier

    DOE Patents [OSTI]

    Ershov, Gennady Moiseevich; Timofeev, Eduard Nikolaevich; Ivanov, Igor Borisovich; Florentiev, Vladimir Leonidovich; Mirzabekov, Andrei Darievich

    1998-01-01

    The method for immobilizing water-soluble bioorganic compounds to capillary-porous carrier comprises application of solutions of water-soluble bioorganic compounds onto a capillary-porous carrier, setting the carrier temperature equal to or below the dew point of the ambient air, keeping the carrier till appearance of water condensate and complete swelling of the carrier, whereupon the carrier surface is coated with a layer of water-immiscible nonluminescent inert oil and is allowed to stand till completion of the chemical reaction of bonding the bioorganic compounds with the carrier.

  20. V-094: IBM Multiple Products Multiple Vulnerabilities | Department...

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

    Multiple Vulnerabilities V-132: IBM Tivoli System Automation Application Manager Multiple Vulnerabilities V-145: IBM Tivoli Federated Identity Manager Products Java Multiple ...

  1. Hot-carrier solar cells using low-dimensional quantum structures

    SciTech Connect (OSTI)

    Watanabe, Daiki; Kasamatsu, Naofumi; Harada, Yukihiro; Kita, Takashi

    2014-10-27

    We propose a high-conversion-efficiency solar cell (SC) utilizing the hot carrier (HC) population in an intermediate-band (IB) of a quantum dot superlattice (QDSL) structure. The bandgap of the host semiconductor in this device plays an important role as an energy-selective barrier for HCs in the QDSLs. According to theoretical calculation using the detailed balance model with an air mass 1.5 spectrum, the optimum IB energy is determined by a trade-off relation between the number of HCs with energy exceeding the conduction-band edge and the number of photons absorbed by the valence band?IB transition. Utilizing experimental data of HC temperature in InAs/GaAs QDSLs, the maximum conversion efficiency under maximum concentration (45?900 suns) has been demonstrated to increase by 12.6% as compared with that for a single-junction GaAs SC.

  2. Method and apparatus for controlling carrier envelope phase

    DOE Patents [OSTI]

    Chang, Zenghu; Li, Chengquan; Moon, Eric

    2011-12-06

    A chirped pulse amplification laser system. The system generally comprises a laser source, a pulse modification apparatus including first and second pulse modification elements separated by a separation distance, a positioning element, a measurement device, and a feedback controller. The laser source is operable to generate a laser pulse and the pulse modification apparatus operable to modify at least a portion of the laser pulse. The positioning element is operable to reposition at least a portion of the pulse modification apparatus to vary the separation distance. The measurement device is operable to measure the carrier envelope phase of the generated laser pulse and the feedback controller is operable to control the positioning element based on the measured carrier envelope phase to vary the separation distance of the pulse modification elements and control the carrier envelope phase of laser pulses generated by the laser source.

  3. Profiling the local carrier concentration across a semiconductor quantum dot

    SciTech Connect (OSTI)

    Walrath, J. C.; Lin, Yen-Hsiang; Huang, S.; Goldman, R. S.

    2015-05-11

    We profile the local carrier concentration, n, across epitaxial InAs/GaAs quantum dots (QDs) consisting of 3D islands on top of a 2D alloy layer. We use scanning thermoelectric microscopy to measure a profile of the temperature gradient-induced voltage, which is converted to a profile of the local Seebeck coefficient, S. The S profile is then converted to a conduction band-edge profile and compared with Poisson-Schrodinger band-edge simulations. Our combined computational-experimental approach suggests a reduced carrier concentration in the QD center in comparison to that of the 2D alloy layer. The relative roles of free carrier trapping and/or dopant expulsion are discussed.

  4. Augmenting drug–carrier compatibility improves tumour nanotherapy efficacy

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

    Zhao, Yiming; Fay, Francois; Hak, Sjoerd; Manuel Perez-Aguilar, Jose; Sanchez-Gaytan, Brenda L.; Goode, Brandon; Duivenvoorden, Raphael; de Lange Davies, Catharina; Bjorkoy, Astrid; Weinstein, Harel; et al

    2016-04-13

    A major goal of cancer nanotherapy is to use nanoparticles as carriers for targeted delivery of anti-tumour agents. The drug–carrier association after intravenous administration is essential for efficient drug delivery to the tumour. However, a large number of currently available nanocarriers are self-assembled nanoparticles whose drug-loading stability is critically affected by the in vivo environment. Here we used in vivo FRET imaging to systematically investigate how drug–carrier compatibility affects drug release in a tumour mouse model. We found the drug’s hydrophobicity and miscibility with the nanoparticles are two independent key parameters that determine its accumulation in the tumour. Next, wemore » applied these findings to improve chemotherapeutic delivery by augmenting the parent drug’s compatibility; as a result, we achieved better antitumour efficacy. Lastly, our results help elucidate nanomedicines’ in vivo fate and provide guidelines for efficient drug delivery.« less

  5. Apparatus for measuring minority carrier lifetimes in semiconductor materials

    DOE Patents [OSTI]

    Ahrenkiel, Richard K.

    1999-01-01

    An apparatus for determining the minority carrier lifetime of a semiconductor sample includes a positioner for moving the sample relative to a coil. The coil is connected to a bridge circuit such that the impedance of one arm of the bridge circuit is varied as sample is positioned relative to the coil. The sample is positioned relative to the coil such that any change in the photoconductance of the sample created by illumination of the sample creates a linearly related change in the input impedance of the bridge circuit. In addition, the apparatus is calibrated to work at a fixed frequency so that the apparatus maintains a consistently high sensitivity and high linearly for samples of different sizes, shapes, and material properties. When a light source illuminates the sample, the impedance of the bridge circuit is altered as excess carriers are generated in the sample, thereby producing a measurable signal indicative of the minority carrier lifetimes or recombination rates of the sample.

  6. NREL Studies Carrier Separation and Transport in Perovskite Solar Cells

    SciTech Connect (OSTI)

    2016-01-01

    NREL scientists studied charge separation and transport in perovskite solar cells by determining the junction structure across the solar device using the nanoelectrical characterization technique of Kelvin probe force microscopy. The distribution of electrical potential across both planar and porous devices demonstrates a p-n junction structure at the interface between titanium dioxide and perovskite. In addition, minority-carrier transport within the devices operates under diffusion/drift. Clarifying the fundamental junction structure provides significant guidance for future research and development. This NREL study points to the fact that improving carrier mobility is a critical factor for continued efficiency gains in perovskite solar cells.

  7. No-carrier-added [1.sup.11 c]putrescine

    DOE Patents [OSTI]

    McPherson, Daniel W.; Fowler, Joanna S.; Wolf, Alfred P.

    1989-01-01

    The invention relates to a new radiolabeled imaging agent, no-carrier-added [1-.sup.11 C]putrescine, and to the use of this very pure material as a radiotracer with positron emission tomography for imaging brain tumors. The invention further relates to the synthesis of no-carrier-added [1-.sup.11 C]putrescine based on the Michael addition of potassium .sup.11 C-labeled cyanide to acrylonitrile followed by reduction of the .sup.11 C-labeled dinitrile. The new method is rapid and efficient and provides radiotracer with a specific activity greater than 1.4 curies per millimol and in a purity greater than 95%.

  8. Test probe for surface mounted leadless chip carrier

    DOE Patents [OSTI]

    Meyer, K.L.; Topolewski, J.

    1987-10-02

    A test probe for a surface mounted leadless chip carrier is disclosed. The probe includes specially designed connector pins which allow size reductions in the probe. A thermoplastic housing provides spring action to ensure good mechanical and electrical contact between the pins and the contact strips of a leadless chip carrier. Other features include flexible wires molded into the housing and two different types of pins alternately placed in the housing. These features allow fabrication of a smaller and simpler test probe. 1 fig.

  9. Energy Conservation

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

    Collegiate Wind Competition Energy By The Numbers: Collegiate Wind Competition Addthis The U.S. Department of Energy Collegiate Wind Competition prepares students from multiple disciplines to enter tomorrow's wind energy workforce. As part of the competition, undergraduate students build and test a wind turbine, establish a deployment strategy, and develop and deliver a business plan.

    Recovery Act Energy By The Numbers: Recovery Act Addthis America is now a world leader in clean energy. But

  10. Interested Parties - Multiple Loan Applications per Developer under Section

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

    1705 Program | Department of Energy Multiple Loan Applications per Developer under Section 1705 Program Interested Parties - Multiple Loan Applications per Developer under Section 1705 Program (86.96 KB) More Documents & Publications Interested Parties - Allowing Multiple Projects per Application for Section 1705 Loan Guarantees Interested Parties - K&L Group Interested Parties - Shipp

  11. Carrier Selective, Passivated Contacts for High Efficiency Silicon...

    Office of Scientific and Technical Information (OSTI)

    ... Research Org: National Renewable Energy Lab. (NREL), Golden, CO (United States) Sponsoring Org: USDOE Office of Energy Efficiency and Renewable Energy Solar Energy Technologies ...

  12. Carrier Selective, Passivated Contacts for High Efficiency Silicon...

    Office of Scientific and Technical Information (OSTI)

    Research Org: National Renewable Energy Lab. (NREL), Golden, CO (United States) Sponsoring Org: USDOE Office of Energy Efficiency and Renewable Energy Solar Energy Technologies ...

  13. Heating subsurface formations by oxidizing fuel on a fuel carrier

    DOE Patents [OSTI]

    Costello, Michael; Vinegar, Harold J.

    2012-10-02

    A method of heating a portion of a subsurface formation includes drawing fuel on a fuel carrier through an opening formed in the formation. Oxidant is supplied to the fuel at one or more locations in the opening. The fuel is combusted with the oxidant to provide heat to the formation.

  14. Labeling of indocyanine green with carrier-free iodine-123

    DOE Patents [OSTI]

    Ansari, Azizullah N.; Lambrecht, Richard M.; Redvanly, Carol S.; Wolf, Alfred P.

    1976-01-01

    The method of labeling indocyanine green (ICG) with carrier-free iodine-123 comprising the steps of condensing xenon-123 on crystals of ICG followed by permitting decay of the .sup.123 Xe a sufficient length of time to produce .sup.123 I-electronically excited ions and atoms which subsequently label ICG.

  15. Integrated circuit with dissipative layer for photogenerated carriers

    DOE Patents [OSTI]

    Myers, D.R.

    1988-04-20

    The sensitivity of an integrated circuit to single-event upsets is decreased by providing a dissipative layer of silicon nitride between a silicon substrate and the active device. Free carriers generated in the substrate are dissipated by the layer before they can build up charge on the active device. 1 fig.

  16. Analyte sensing mediated by adapter/carrier molecules

    DOE Patents [OSTI]

    Bayley, Hagan; Braha, Orit; Gu, LiQun

    2002-07-30

    This invention relates to an improved method and system for sensing of one or more analytes. A host molecule, which serves as an adapter/carrier, is used to facilitate interaction between the analyte and the sensor element. A detectable signal is produced reflecting the identity and concentration of analyte present.

  17. METHOD OF IMPROVING THE CARRIER PRECIPITATION OF PLUTONIUM

    DOE Patents [OSTI]

    Kamack, H.J.; Balthis, J.H.

    1958-12-01

    Plutonium values can be recovered from acidic solutlons by adding lead nitrate, hydrogen fluoride, lantha num nitrate, and sulfurlc acid to the solution to form a carrler preclpitate. The lead sulfate formed improves the separatlon characteristics of the lanthanum fluoride carrier precipitate,

  18. Multiple density layered insulator

    DOE Patents [OSTI]

    Alger, T.W.

    1994-09-06

    A multiple density layered insulator for use with a laser is disclosed which provides at least two different insulation materials for a laser discharge tube, where the two insulation materials have different thermoconductivities. The multiple layer insulation materials provide for improved thermoconductivity capability for improved laser operation. 4 figs.

  19. Multiple density layered insulator

    DOE Patents [OSTI]

    Alger, Terry W.

    1994-01-01

    A multiple density layered insulator for use with a laser is disclosed wh provides at least two different insulation materials for a laser discharge tube, where the two insulation materials have different thermoconductivities. The multiple layer insulation materials provide for improved thermoconductivity capability for improved laser operation.

  20. V-132: IBM Tivoli System Automation Application Manager Multiple

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

    Vulnerabilities | Department of Energy 2: IBM Tivoli System Automation Application Manager Multiple Vulnerabilities V-132: IBM Tivoli System Automation Application Manager Multiple Vulnerabilities April 12, 2013 - 6:00am Addthis PROBLEM: IBM has acknowledged multiple vulnerabilities in IBM Tivoli System Automation Application Manager PLATFORM: The vulnerabilities are reported in IBM Tivoli System Automation Application Manager versions 3.1, 3.2, 3.2.1, and 3.2.2 ABSTRACT: Multiple security

  1. V-180: IBM Application Manager For Smart Business Multiple Vulnerabilities

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

    | Department of Energy 0: IBM Application Manager For Smart Business Multiple Vulnerabilities V-180: IBM Application Manager For Smart Business Multiple Vulnerabilities June 18, 2013 - 12:38am Addthis PROBLEM: IBM Application Manager For Smart Business Multiple Vulnerabilities PLATFORM: IBM Application Manager For Smart Business 1.x ABSTRACT: A security issue and multiple vulnerabilities have been reported in IBM Application Manager For Smart Business REFERENCE LINKS: Security Bulletin

  2. Interested Parties - Allowing Multiple Projects per Application for Section

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

    1705 Loan Guarantees | Department of Energy Allowing Multiple Projects per Application for Section 1705 Loan Guarantees Interested Parties - Allowing Multiple Projects per Application for Section 1705 Loan Guarantees Multiple_Projects_Section_1705_Loan_Guarantees.pdf (24.78 KB) More Documents & Publications Interested Parties - Multiple Loan Applications per Developer under Section 1705 Program Interested Parties - K&L Group Lobbyist Disclosure Form - John Thorne

  3. Recirculation in multiple wave conversions

    SciTech Connect (OSTI)

    Kaufman, A. N.; Brizard, A.J.; Kaufman, A.N.; Tracy, E.R.

    2008-07-30

    A one-dimensional multiple wave-conversion model is constructed that allows energy recirculation in ray phase space. Using a modular eikonal approach, the connection coefficients for this model are calculated by ray phase-space methods. Analytical results (confirmed numerically) show that all connection coefficients exhibit interference effects that depend on an interference phase, calculated from the coupling constants and the area enclosed by the intersecting rays. This conceptual model, which focuses on the topology of intersecting rays in phase space, is used to investigate how mode conversion between primary and secondary waves is modified by the presence of a tertiary wave.

  4. Energy Forms or Energy Carriers(G, Herrmann et al. 1983) | OpenEI...

    Open Energy Info (EERE)

    topics related to ESI Posted: 15 Nov 2012 - 13:55 by Qinsun Qinsun Prospects for Nuclear Power(Davis 2012) Posted: 15 Nov 2012 - 13:36 by Qinsun 1 of 4 Groups Menu You...

  5. Comments of East Central Energy- Minnesota | Department of Energy

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

    East Central Energy- Minnesota Comments of East Central Energy- Minnesota Because of the lack of ubiquitous coverage by major carriers or operating telephone companies, East Central Energy has contracted with our G&T, Great River Energy for private wireless services to our substations. No single vendor or combination of several vendors could provide an integrated solution Great River Energy has deployed a fully integrated IP network to 36 of ECE's remote sites of our electric system. The IP

  6. Multiple shell fusion targets

    DOE Patents [OSTI]

    Lindl, J.D.; Bangerter, R.O.

    1975-10-31

    Multiple shell fusion targets for use with electron beam and ion beam implosion systems are described. The multiple shell targets are of the low-power type and use a separate relatively low Z, low density ablator at large radius for the outer shell, which reduces the focusing and power requirements of the implosion system while maintaining reasonable aspect ratios. The targets use a high Z, high density pusher shell placed at a much smaller radius in order to obtain an aspect ratio small enough to protect against fluid instability. Velocity multiplication between these shells further lowers the power requirements. Careful tuning of the power profile and intershell density results in a low entropy implosion which allows breakeven at low powers. For example, with ion beams as a power source, breakeven at 10-20 Terrawatts with 10 MeV alpha particles for imploding a multiple shell target can be accomplished.

  7. United States Virgin Islands: Energy Resources | Open Energy...

    Open Energy Info (EERE)

    (CLEAN Partner Activity) Energy Incentives for United States Virgin Islands Solar Water Heater Rebate Program (U.S. Virgin Islands) Southern States Energy Compact (Multiple...

  8. NorthWestern Energy (Gas)- Commercial Energy Efficiency Rebate Program

    Broader source: Energy.gov [DOE]

    NorthWestern Energy offers multiple rebate programs for commercial and industrial customers to make energy efficient improvements to their businesses. Incentives are available for heating,...

  9. Options for Energy Efficiency and Renewable Energy in the Final...

    U.S. Energy Information Administration (EIA) Indexed Site

    ... energy savings o Criteria pollution reductions in SIPs o Carbon reductions ... beyond their own areas of expertise (i.e. air, energy, economics) * The Multiple Benefits ...

  10. Suppression of thermal carrier escape and efficient photo-carrier generation by two-step photon absorption in InAs quantum dot intermediate-band solar cells using a dot-in-well structure

    SciTech Connect (OSTI)

    Asahi, S.; Teranishi, H.; Kasamatsu, N.; Kada, T.; Kaizu, T.; Kita, T.

    2014-08-14

    We investigated the effects of an increase in the barrier height on the enhancement of the efficiency of two-step photo-excitation in InAs quantum dot (QD) solar cells with a dot-in-well structure. Thermal carrier escape of electrons pumped in QD states was drastically reduced by sandwiching InAs/GaAs QDs with a high potential barrier of Al{sub 0.3}Ga{sub 0.7}As. The thermal activation energy increased with the introduction of the barrier. The high potential barrier caused suppression of thermal carrier escape and helped realize a high electron density in the QD states. We observed efficient two-step photon absorption as a result of the high occupancy of the QD states at room temperature.