Science.gov

Sample records for hybrid biothermal conversion

  1. A process study of the biothermal conversion of water hyacinths to methane

    NASA Astrophysics Data System (ADS)

    Butner, R. S.; Elliott, D. C.; Sealock, L. J., Jr.; Chynoweth, D. P.

    1987-05-01

    A hybrid process employing both biological and thermochemical conversion of biomass to methane was studied. A unique high-moisture catalytic gasifier concept was used to gasify the effluent from an anaerobic digester. An ASPEN-PLUS/sup tm/ simulation of the process concept was based upon experimental data obtained from individual process components. An overall process efficiency of 78.1 to 94.1 percent was determined, depending upon the process configuration. Extensive use of heat and power recovery is required to achieve the high efficiencies reported for the process.

  2. Biothermal simulation of scuba divers

    NASA Technical Reports Server (NTRS)

    Montgomery, L. D.

    1975-01-01

    A biothermal model of the immersed man is presented and validated. Comparisons are made between analytic and experimental values of temperature-vs-time profiles for neck-immersed seminude and wet-suited subjects. An engineering example is presented to demonstrate how the model may be used to evaluate proposed life-support system designs.

  3. Biothermal simulation of scuba divers

    NASA Technical Reports Server (NTRS)

    Montgomery, L. D.

    1975-01-01

    A biothermal model of the immersed man is presented and validated. Comparisons are made between analytic and experimental values of temperature-vs-time profiles for neck-immersed seminude and wet-suited subjects. An engineering example is presented to demonstrate how the model may be used to evaluate proposed life-support system designs.

  4. Biothermal gasification of biomass

    SciTech Connect

    Chynoweth, D.P.; Srivastava, V.J.; Henry, M.P.; Tarman, P.B.

    1980-01-01

    The BIOTHERMGAS Process is described for conversion of biomass, organic residues, and peat to substitute natural gas (SNG). This new process, under development at IGT, combines biological and thermal processes for total conversion of a broad variety of organic feeds (regardless of water or nutrient content). The process employs thermal gasification for conversion of refractory digester residues. Ammonia and other inorganic nutrients are recycled from the thermal process effluent to the bioconversion unit. Biomethanation and catalytic methanation are presented as alternative processes for methanation of thermal conversion product gases. Waste heat from the thermal component is used to supply the digester heat requirements of the bioconversion component. The results of a preliminary systems analysis of three possible applications of this process are presented: (1) 10,000 ton/day Bermuda grass plant with catalytic methanation; (2) 10,000 ton/day Bermuda grass plant with biomethanation; and (3) 1000 ton/day municipal solid waste (MSW) sewage sludge plant with biomethanation. The results indicate that for these examples, performance is superior to that expected for biological or thermal processes used separately. The results of laboratory studies presented suggest that effective conversion of thermal product gases can be accomplished by biomethanation.

  5. Biothermal sensing of a torsional artificial muscle

    NASA Astrophysics Data System (ADS)

    Lee, Sung-Ho; Kim, Tae Hyeob; Lima, Márcio D.; Baughman, Ray H.; Kim, Seon Jeong

    2016-02-01

    Biomolecule responsive materials have been studied intensively for use in biomedical applications as smart systems because of their unique property of responding to specific biomolecules under mild conditions. However, these materials have some challenging drawbacks that limit further practical application, including their speed of response and mechanical properties, because most are based on hydrogels. Here, we present a fast, mechanically robust biscrolled twist-spun carbon nanotube yarn as a torsional artificial muscle through entrapping an enzyme linked to a thermally sensitive hydrogel, poly(N-isopropylacrylamide), utilizing the exothermic catalytic reaction of the enzyme. The induced rotation reached an equilibrated angle in less than 2 min under mild temperature conditions (25-37 °C) while maintaining the mechanical properties originating from the carbon nanotubes. This biothermal sensing of a torsional artificial muscle offers a versatile platform for the recognition of various types of biomolecules by replacing the enzyme, because an exothermic reaction is a general property accompanying a biochemical transformation.Biomolecule responsive materials have been studied intensively for use in biomedical applications as smart systems because of their unique property of responding to specific biomolecules under mild conditions. However, these materials have some challenging drawbacks that limit further practical application, including their speed of response and mechanical properties, because most are based on hydrogels. Here, we present a fast, mechanically robust biscrolled twist-spun carbon nanotube yarn as a torsional artificial muscle through entrapping an enzyme linked to a thermally sensitive hydrogel, poly(N-isopropylacrylamide), utilizing the exothermic catalytic reaction of the enzyme. The induced rotation reached an equilibrated angle in less than 2 min under mild temperature conditions (25-37 °C) while maintaining the mechanical properties

  6. Lower Hybrid to Whistler Wave Conversion

    SciTech Connect

    Winske, Dan

    2012-07-16

    In this presentation we discuss recent work concerning the conversion of whistler waves to lower hybrid waves (as well as the inverse process). These efforts have been motivated by the issue of attenuation of upward propagating whistler waves in the ionosphere generated by VLF transmitters on the ground, i.e., the 'Starks 20 db' problem, which affects the lifetimes of energetic electrons trapped in the geomagnetic field at low magnetic altitude (L). We discuss recent fluid and kinetic plasma simulations as well as ongoing experiments at UCLA to quantify linear and nonlinear mode conversion of lower hybrid to whistler waves.

  7. Biothermal Model of Patient for Brain Hypothermia Treatment

    NASA Astrophysics Data System (ADS)

    Wakamatsu, Hidetoshi; Gaohua, Lu

    A biothermal model of patient is proposed and verified for the brain hypothermia treatment, since the conventionally applied biothermal models are inappropriate for their unprecedented application. The model is constructed on the basis of the clinical practice of the pertinent therapy and characterized by the mathematical relation with variable ambient temperatures, in consideration of the clinical treatments such as the vital cardiopulmonary regulation. It has geometrically clear representation of multi-segmental core-shell structure, database of physiological and physical parameters with a systemic state equation setting the initial temperature of each compartment. Its step response gives the time constant about 3 hours in agreement with clinical knowledge. As for the essential property of the model, the dynamic temperature of its face-core compartment is realized, which corresponds to the tympanic membrane temperature measured under the practical anesthesia. From the various simulations consistent with the phenomena of clinical practice, it is concluded that the proposed model is appropriate for the theoretical analysis and clinical application to the brain hypothermia treatment.

  8. Energy Conversion and Storage Requirements for Hybrid Electric Aircraft

    NASA Technical Reports Server (NTRS)

    Misra, Ajay

    2016-01-01

    Among various options for reducing greenhouse gases in future large commercial aircraft, hybrid electric option holds significant promise. In the hybrid electric aircraft concept, gas turbine engine is used in combination with an energy storage system to drive the fan that propels the aircraft, with gas turbine engine being used for certain segments of the flight cycle and energy storage system being used for other segments. The paper will provide an overview of various energy conversion and storage options for hybrid electric aircraft. Such options may include fuel cells, batteries, super capacitors, multifunctional structures with energy storage capability, thermoelectric, thermionic or a combination of any of these options. The energy conversion and storage requirements for hybrid electric aircraft will be presented. The role of materials in energy conversion and storage systems for hybrid electric aircraft will be discussed.

  9. Vehicle conversion to hybrid gasoline/alternative fuel operation

    NASA Technical Reports Server (NTRS)

    Donakowski, T. D.

    1982-01-01

    The alternative fuels considered are compressed natural gas (CNG), liquefied natural gas (LNG), liquid petroleum gas (LPG), and methanol; vehicles were required to operate in a hybrid or dual-fuel gasoline/alternative fuel mode. Economic feasibility was determined by comparing the costs of continued use of gasoline fuel with the use of alternative fuel and retrofitted equipment. Differences in the amounts of future expenditures are adjusted by means of a total life-cycle costing. All fuels studied are technically feasible to allow a retrofit conversion to hybrid gasoline/alternative fuel operation except for methanol. Conversion to LPG is not recommended for vehicles with more than 100,000 km (60,000 miles) of prior use. Methanol conversion is not recommended for vehicles with more than 50,00 km (30,000 miles).

  10. Multi-dimensional conversion to the ion-hybrid mode

    SciTech Connect

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

    1996-12-31

    We first demonstrate that the dispersion matrix for linear conversion of a magnetosonic wave to an ion-hybrid wave (as in a D-T plasma) can be congruently transformed to Friedland`s normal form. As a result, this conversion can be represented as a two-step process of successive linear conversions in phase space. We then proceed to study the multi-dimensional case of tokamak geometry. After fourier transforming the toroidal dependence, we deal with the two-dimensional poloidal xy-plane and the two-dimensional k{sub x}k{sub y}-plane, forming a four-dimensional phase space. The dispersion manifolds for the magnetosonic wave [D{sub M} (x, k) = 0] and the ion-hybrid wave [D{sub H} (x, k) = 0] are each three-dimensional. (Their intersection, on which mode conversion occurs, is two-dimensional.) The incident magnetosonic wave (radiated by an antenna) is a two-dimensional set of rays (a lagrangian manifold): k(x) = {del}{theta}(x), with {theta}(x) the phase of the magnetosonic wave. When these rays pierce the ion-hybrid dispersion manifold, they convert to a set of ion-hybrid rays. Then, when those rays intersect the magnetosonic dispersion manifold, they convert to a set of {open_quotes}reflected{close_quotes} magnetosonic rays. This set of rays is distinct from the set of incident rays that have been reflected by the inner surface of the tokamak plasma. As a result, the total destructive interference that can occur in the one-dimensional case may become only partial. We explore the implications of this startling phenomenon both analytically and geometrically.

  11. Studying bio-thermal effects at and around MSW dumps using Satellite Remote Sensing and GIS.

    PubMed

    Mahmood, Khalid; Batool, Syeda Adila; Chaudhry, Muhammad Nawaz

    2016-09-01

    Estimating negative impacts of MSW dumps on its surrounding environment is the key requirement for any remedial measures. This study has been undertaken to map bio-thermal effects of MSW dumping at and around dumping facilities (non-engineered) using satellite imagery for Faisalabad, Pakistan. Thirty images of Landsat 8 have been selected after validation for the accuracy of their observational details from April 2013 to October 2015. Land Surface Temperature (LST), NDVI, SAVI and MSAVI have been derived from these images through Digital Image Processing (DIP) and have been subjected to spatio-temporal analysis in GIS environment. MSW dump has been found with average temperature elevation of 4.3K and 2.78K from nearby agriculture land and urban settlement respectively. Vegetation health has been used as the bio-indicator of MSW effects and is implemented through NDVI, SAVI, MSAVI. Spatial analyses have been used to mark boundary of bio-thermally affected zone around dumped MSW and measure 700m. Seasonal fluctuations of elevated temperatures and boundary of the bio-thermally affected zones have also been discussed. Based on the direct relation found between vegetation vigor and the level of deterioration within the bio-thermally affected region, use of crops with heavy vigor is recommended to study MSW hazard influence using bio-indicators of vegetation health. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Macromolecule-to-amphiphile conversion process of a polyoxometalate-polymer hybrid and assembled hybrid vesicles.

    PubMed

    Xiao, Yu; Han, Yao-Kun; Xia, Nan; Hu, Min-Biao; Zheng, Ping; Wang, Wei

    2012-09-03

    We report our findings on the macromolecule-to-amphiphile conversion process of a polyoxometalate-polymer hybrid and the assembled hybrid vesicles formed by aggregation of the hybrid amphiphile. The polyoxometalate-polymer hybrid is composed of a polyoxometalate (POM) cluster, which is covered by five tetrabutylammonium (Bu(4)N(+)) countercations, and a polystyrene (PS) chain. Through a cation-exchange process the Bu(4)N(+) countercations can be replaced by protons to form a hybrid amphiphile composed of a hydrophilic, protonated POM cluster and a hydrophobic PS chain. By implementing a directed one-dimensional diffusion and analyzing the diffusion data, we confirmed that the diffusion of solvated protons rather than macromolecules or aggregates is the key factor controlling the conversion process. Once the giant hybrid amphiphiles were formed, they immediately assembled into kinetically favored vesicular aggregates. During subsequent annealing these vesicular aggregates were transformed into thermodynamically stable vesicular aggregates with a perfect vesicle structure. The success in the preparation of the POM-containing hybrid vesicles provides us with an opportunity of preparing POM-functionalized vesicles. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Hybrid bioinorganic approach to solar-to-chemical conversion.

    PubMed

    Nichols, Eva M; Gallagher, Joseph J; Liu, Chong; Su, Yude; Resasco, Joaquin; Yu, Yi; Sun, Yujie; Yang, Peidong; Chang, Michelle C Y; Chang, Christopher J

    2015-09-15

    Natural photosynthesis harnesses solar energy to convert CO2 and water to value-added chemical products for sustaining life. We present a hybrid bioinorganic approach to solar-to-chemical conversion in which sustainable electrical and/or solar input drives production of hydrogen from water splitting using biocompatible inorganic catalysts. The hydrogen is then used by living cells as a source of reducing equivalents for conversion of CO2 to the value-added chemical product methane. Using platinum or an earth-abundant substitute, α-NiS, as biocompatible hydrogen evolution reaction (HER) electrocatalysts and Methanosarcina barkeri as a biocatalyst for CO2 fixation, we demonstrate robust and efficient electrochemical CO2 to CH4 conversion at up to 86% overall Faradaic efficiency for ≥ 7 d. Introduction of indium phosphide photocathodes and titanium dioxide photoanodes affords a fully solar-driven system for methane generation from water and CO2, establishing that compatible inorganic and biological components can synergistically couple light-harvesting and catalytic functions for solar-to-chemical conversion.

  14. Hybrid bioinorganic approach to solar-to-chemical conversion

    PubMed Central

    Nichols, Eva M.; Gallagher, Joseph J.; Liu, Chong; Su, Yude; Resasco, Joaquin; Yu, Yi; Sun, Yujie; Yang, Peidong; Chang, Michelle C. Y.; Chang, Christopher J.

    2015-01-01

    Natural photosynthesis harnesses solar energy to convert CO2 and water to value-added chemical products for sustaining life. We present a hybrid bioinorganic approach to solar-to-chemical conversion in which sustainable electrical and/or solar input drives production of hydrogen from water splitting using biocompatible inorganic catalysts. The hydrogen is then used by living cells as a source of reducing equivalents for conversion of CO2 to the value-added chemical product methane. Using platinum or an earth-abundant substitute, α-NiS, as biocompatible hydrogen evolution reaction (HER) electrocatalysts and Methanosarcina barkeri as a biocatalyst for CO2 fixation, we demonstrate robust and efficient electrochemical CO2 to CH4 conversion at up to 86% overall Faradaic efficiency for ≥7 d. Introduction of indium phosphide photocathodes and titanium dioxide photoanodes affords a fully solar-driven system for methane generation from water and CO2, establishing that compatible inorganic and biological components can synergistically couple light-harvesting and catalytic functions for solar-to-chemical conversion. PMID:26305947

  15. Biothermal modeling of transurethral ultrasound applicators for MR-guided prostate thermal therapy (Invited Paper)

    NASA Astrophysics Data System (ADS)

    Ross, Anthony B.; Diederich, Chris J.; Nau, William H.; Tyreus, Per D.; Gill, Harcharan; Bouley, Donna; Butts, R. K.; Rieke, Viola; Daniel, Bruce; Sommer, Graham

    2005-04-01

    Thermal ablation is a minimally-invasive treatment option for benign prostatic hyperplasia (BPH) and localized prostate cancer. Accurate spatial control of thermal dose delivery is paramount to improving thermal therapy efficacy and avoiding post-treatment complications. We have recently developed three types of transurethral ultrasound applicators, each with different degrees of heating selectivity. These applicators have been evaluated in vivo in coordination with magnetic resonance temperature imaging, and demonstrated to accurately ablate specific regions of the canine prostate. A finite difference biothermal model of the three types of transurethral ultrasound applicators (sectored tubular, planar, and curvilinear transducer sections) was developed and used to further study the performance and heating capabilities of each these devices. The biothermal model is based on the Pennes bioheat equation. The acoustic power deposition pattern corresponding to each applicator type was calculated using the rectangular radiator approximation to the Raleigh Sommerfield diffraction integral. In this study, temperature and thermal dose profiles were calculated for different treatment schemes and target volumes, including single shot and angular scanning procedures. This study also demonstrated the ability of the applicators to conform the cytotoxic thermal dose distribution to a predefined target area. Simulated thermal profiles corresponded well with MR temperature images from previous in vivo experiments. Biothermal simulations presented in this study reinforce the potential of improved efficacy of transurethral ultrasound thermal therapy of prostatic disease.

  16. Hybrid acoustic energy harvesting using combined electromagnetic and piezoelectric conversion

    NASA Astrophysics Data System (ADS)

    Khan, Farid Ullah; Izhar

    2016-02-01

    This paper reports a novel hybrid acoustic energy harvester. The harvester utilizes both the electromagnetic and piezoelectric conversion mechanisms simultaneously to convert the ambient acoustical noise into electrical power for self-powered wireless sensor nodes. The proposed harvester is comprised of a Helmholtz resonator, two magnets mounted on a piezoelectric plate, and a wound coil located under the magnets. The harvester is characterized both under harmonic and real random acoustical excitations. In-lab, under harmonic acoustical excitation at a sound pressure level of 130 dB and frequency of 2.1 kHz, an optimum power of 2.86 μW (at 114 Ω optimum load) is obtained from electromagnetic conversion and 50 μW (at 1000 Ω optimum load) is generated by the piezoelectric harvester's part. Moreover, in real acoustical environment of a domestic electric generator the peak voltages of 40 and 123 mV are produced by the electromagnetic and piezoelectric portions of the acoustic energy harvester.

  17. On-chip optical mode conversion based on dynamic grating in photonic-phononic hybrid waveguide

    PubMed Central

    Chen, Guodong; Zhang, Ruiwen; Sun, Junqiang

    2015-01-01

    We present a scheme for reversible and tunable on-chip optical mode conversion based on dynamic grating in a hybrid photonic-phononic waveguide. The dynamic grating is built up through the acousto-optic effect and the theoretical model of the optical mode conversion is developed by considering the geometrical deformation and refractive index change. Three kinds of mode conversions are able to be realized using the same hybrid waveguide structure in a large bandwidth by only changing the launched acoustic frequency. The complete mode conversion can be achieved by choosing a proper acoustic power under a given waveguide length. PMID:25996236

  18. 2010 Honda Civic Hybrid UltraBattery Conversion 5577 - Hybrid Electric Vehicle Battery Test Results

    SciTech Connect

    Tyler Gray; Matthew Shirk; Jeffrey Wishart

    2013-07-01

    The U.S. Department of Energy Advanced Vehicle Testing Activity Program consists of vehicle, battery, and infrastructure testing on advanced technology related to transportation. The activity includes tests on hybrid electric vehicles (HEVs), including testing the HEV batteries when both the vehicles and batteries are new and at the conclusion of on-road fleet testing. This report documents battery testing performed for the 2010 Honda Civic HEV UltraBattery Conversion (VIN JHMFA3F24AS005577). Battery testing was performed by the Electric Transportation Engineering Corporation dba ECOtality North America. The Idaho National Laboratory and ECOtality North America collaborate on the AVTA for the Vehicle Technologies Program of the DOE.

  19. A mathematical model of respiratory and biothermal dynamics in brain hypothermia treatment.

    PubMed

    Gaohua, Lu; Kimura, Hidenori

    2008-04-01

    Brain hypothermia treatment (BHT) requires proper mechanical ventilation and therapeutic cooling. The cooling strategy for BHT has been mainly discussed in the literature while little information is available on the respiratory management. We first developed a mathematical model that integrates the respiratory and biothermal dynamics to discuss the simultaneous managements of mechanical ventilation and therapeutic cooling. The effect of temperature on the linear approximations of hemoglobin-oxygen dissociation, together with temperature dependency of metabolism, is introduced during modeling to combine the respiratory system with the biothermal system. By comparing its transient behavior with published data, the model is verified qualitatively and then quantitatively. Second, model-based simulation of the current respiratory management in BHT suggests reduction of minute ventilation in reference to cooled brain temperature to stabilize the states of blood and brain oxygenation. Lastly, the relationship between cooling temperature and minute ventilation is approximated by a linear first-order transfer function of static gain 0.61min(-1) degrees C(-1) and time constant 8.9 h, which is used to develop a feedforward control to tune the mechanical ventilator in concert with temperature regulation of the cooling blanket. Discussion of the model encourages further studies that provide direct evidence from clinical experiments.

  20. Biothermal Model of Patient and Automatic Control System of Brain Temperature for Brain Hypothermia Treatment

    NASA Astrophysics Data System (ADS)

    Wakamatsu, Hidetoshi; Gaohua, Lu

    Various surface-cooling apparatus such as the cooling cap, muffler and blankets have been commonly used for the cooling of the brain to provide hypothermic neuro-protection for patients of hypoxic-ischemic encephalopathy. The present paper is aimed at the brain temperature regulation from the viewpoint of automatic system control, in order to help clinicians decide an optimal temperature of the cooling fluid provided for these three types of apparatus. At first, a biothermal model characterized by dynamic ambient temperatures is constructed for adult patient, especially on account of the clinical practice of hypothermia and anesthesia in the brain hypothermia treatment. Secondly, the model is represented by the state equation as a lumped parameter linear dynamic system. The biothermal model is justified from their various responses corresponding to clinical phenomena and treatment. Finally, the optimal regulator is tentatively designed to give clinicians some suggestions on the optimal temperature regulation of the patient’s brain. It suggests the patient’s brain temperature could be optimally controlled to follow-up the temperature process prescribed by the clinicians. This study benefits us a great clinical possibility for the automatic hypothermia treatment.

  1. Nanostructured hybrid ZnO thin films for energy conversion

    PubMed Central

    2011-01-01

    We report on hybrid films based on ZnO/organic dye prepared by electrodeposition using tetrasulfonated copper phthalocyanines (TS-CuPc) and Eosin-Y (EoY). Both the morphology and porosity of hybrid ZnO films are highly dependent on the type of dyes used in the synthesis. High photosensitivity was observed for ZnO/EoY films, while a very weak photoresponse was obtained for ZnO/TS-CuPc films. Despite a higher absorption coefficient of TS-CuPc than EoY, in ZnO/EoY hybrid films, the excited photoelectrons between the EoY levels can be extracted through ZnO, and the porosity of ZnO/EoY can also be controlled. PMID:21711909

  2. A novel power conversion circuit for cost-effective battery-fuel cell hybrid systems

    NASA Astrophysics Data System (ADS)

    Choi, Dae-Kyu; Lee, Byoung-Kuk; Choi, Se-Wan; Won, Chung-Yuen; Yoo, Dong-Wook

    The purpose of this paper is to develop a novel power conversion circuit for cost-effective battery-fuel cell hybrid systems. First of all, the various reduced parts power conversion systems (PCS) are overviewed and an advanced dc-dc boost converter and a bidirectional dc-dc converter are proposed. Theoretical explanation and informative simulation and experimental results are provided, along with the evaluation of the developed topologies in performance points of view.

  3. Modular approach for conversion to the ion-hybrid wave and {alpha} gyroresonance

    SciTech Connect

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

    1997-04-01

    Linear conversion of an incoming magnetosonic wave (a.k.a. fast or compressional wave) to an ion-hybrid wave can be considered as a 3-step process in ray phase space. This is demonstrated by casting the cold-fluid model into the Friedland-Kaufman normal form for linear mode conversion. First, the incoming magnetosonic ray (MSR) converts a fraction of its action to an {ital intermediate} ion-hybrid ray (IHR), with the transmitted ray proceeding through the conversion layer. The IHR propagates in k-space to a {ital second} conversion point, where it converts in turn a fraction of its action into a {ital reflected} MSR, with the remainder of the its action constituting the {ital converted} IHR. The modular approach gives {ital exact} agreement with the more standard Budden formulation for the transmission, reflection and conversion coefficients, but has the important advantage of exposing the intermediate IHR. The existence of the intermediate IHR has important physical consequences as it can resonate with {alpha} particles. We estimate the time-integrated damping coefficient between the two conversions and show that {integral}{gamma}dt is of order {minus}100, thus the IH wave is completely annihilated between conversions and transfers its energy to the {alpha}{close_quote}s. This suggests that proposals to use the IH mode for current drive or DT heating are likely to fail in the presence of fusion {alpha}{close_quote}s. {copyright} {ital 1997 American Institute of Physics.}

  4. Conversion of Solar Two to a Kokhala hybrid power tower

    SciTech Connect

    Price, H.W.

    1997-06-01

    The continued drop in energy prices and restructuring of the utility industry have reduced the likelihood that a follow-on commercial 100-MW, power tower project will be built immediately following the Solar Two demonstration project. Given this, it would be desirable to find a way to extend the life of the Solar Two project to allow the plant to operate as a showcase for future power tower projects. This paper looks at the possibility of converting Solar Two into a commercial Kokhala hybrid power tower plant at the end of its demonstration period in 1998. The study identifies two gas turbines that could be integrated into a Kokhala cycle at Solar Two and evaluates the design, expected performance, and economics of each of the systems. The study shows that a commercial Kokhala project at Solar Two could produce power at a cost of less than 7 e/kWhr.

  5. Hybrid organic/inorganic thin-film multijunction solar cells exceeding 11% power conversion efficiency.

    PubMed

    Roland, Steffen; Neubert, Sebastian; Albrecht, Steve; Stannowski, Bernd; Seger, Mark; Facchetti, Antonio; Schlatmann, Rutger; Rech, Bernd; Neher, Dieter

    2015-02-18

    Hybrid multijunction solar cells comprising hydrogenated amorphous silicon and an organic bulk heterojunction are presented, reaching 11.7% power conversion efficiency. The benefits of merging inorganic and organic subcells are pointed out, the optimization of the cells, including optical modeling predictions and tuning of the recombination contact are described, and an outlook of this technique is given.

  6. Efficient photovoltaic conversion of graphene-carbon nanotube hybrid films grown from solid precursors

    NASA Astrophysics Data System (ADS)

    Gan, Xin; Lv, Ruitao; Bai, Junfei; Zhang, Zexia; Wei, Jinquan; Huang, Zheng-Hong; Zhu, Hongwei; Kang, Feiyu; Terrones, Mauricio

    2015-09-01

    Large-area (e.g. centimeter size) graphene sheets are usually synthesized via pyrolysis of gaseous carbon precursors (e.g. methane) on metal substrates like Cu using chemical vapor deposition (CVD), but the presence of grain boundaries and the residual polymers during transfer deteriorates significantly the properties of the CVD graphene. If carbon nanotubes (CNTs) can be covalently bonded to graphene, the hybrid system could possess excellent electrical conductivity, transparency and mechanical strength. In this work, conducting and transparent CNT-graphene hybrid films were synthesized by a facile solid precursor pyrolysis method. Furthermore, the synthesized CNT-graphene hybrid films display enhanced photovoltaic conversion efficiency when compared to devices based on CNT membranes or graphene sheets. Upon chemical doping, the graphene-CNT/Si solar cells reveal power conversion efficiencies up to 8.50%.

  7. Polarization conversion in plasmonic nanoantennas for metasurfaces using structural asymmetry and mode hybridization

    PubMed Central

    Wiecha, Peter R.; Black, Leo-Jay; Wang, Yudong; Paillard, Vincent; Girard, Christian; Muskens, Otto L.; Arbouet, Arnaud

    2017-01-01

    Polarization control using single plasmonic nanoantennas is of interest for subwavelength optical components in nano-optical circuits and metasurfaces. Here, we investigate the role of two mechanisms for polarization conversion by plasmonic antennas: Structural asymmetry and plasmon hybridization through strong coupling. As a model system we investigate L-shaped antennas consisting of two orthogonal nanorods which lengths and coupling strength can be independently controlled. An analytical model based on field susceptibilities is developed to extract key parameters and to address the influence of antenna morphology and excitation wavelength on polarization conversion efficiency and scattering intensities. Optical spectroscopy experiments performed on individual antennas, further supported by electrodynamical simulations based on the Green Dyadic Method, confirm the trends extracted from the analytical model. Mode hybridization and structural asymmetry allow address-ing different input polarizations and wavelengths, providing additional degrees of freedom for agile polarization conversion in nanophotonic devices. PMID:28102320

  8. Polarization conversion in plasmonic nanoantennas for metasurfaces using structural asymmetry and mode hybridization

    NASA Astrophysics Data System (ADS)

    Wiecha, Peter R.; Black, Leo-Jay; Wang, Yudong; Paillard, Vincent; Girard, Christian; Muskens, Otto L.; Arbouet, Arnaud

    2017-01-01

    Polarization control using single plasmonic nanoantennas is of interest for subwavelength optical components in nano-optical circuits and metasurfaces. Here, we investigate the role of two mechanisms for polarization conversion by plasmonic antennas: Structural asymmetry and plasmon hybridization through strong coupling. As a model system we investigate L-shaped antennas consisting of two orthogonal nanorods which lengths and coupling strength can be independently controlled. An analytical model based on field susceptibilities is developed to extract key parameters and to address the influence of antenna morphology and excitation wavelength on polarization conversion efficiency and scattering intensities. Optical spectroscopy experiments performed on individual antennas, further supported by electrodynamical simulations based on the Green Dyadic Method, confirm the trends extracted from the analytical model. Mode hybridization and structural asymmetry allow address-ing different input polarizations and wavelengths, providing additional degrees of freedom for agile polarization conversion in nanophotonic devices.

  9. Mode hybridization and conversion in silicon-on-insulator nanowires with angled sidewalls.

    PubMed

    Dai, Daoxin; Zhang, Ming

    2015-12-14

    The mode property and light propagation in a tapered silicon-on-insulator (SOI) nanowire with angled sidewalls is analyzed. Mode hybridization is observed and mode conversion between the TM fundamental mode and higher-order TE modes happens when light propagates in a waveguide taper which is used very often in the design of photonic integrated devices. This mode conversion ratio is possible to be very high (even close to 100%) when the taper is long enough to be adiabatic, which might be useful for some applications of multimode photonics. When the mode conversion is undesired to avoid any excess loss as well as crosstalk for photonic integrated circuits, one can depress the mode conversion by compensating the vertical asymmetry in the way of reducing the sidewall angle or introducing an optimal refractive index for the upper-cladding. It is also possible to eliminate the undesired mode conversion almost and improve the desired mode conversion greatly by introducing an abrupt junction connecting two sections with different widths to jump over the mode hybridization region.

  10. Mode conversion of fast Alfvén waves at the ion-ion hybrid resonance

    NASA Astrophysics Data System (ADS)

    Ram, A. K.; Bers, A.; Schultz, S. D.; Fuchs, V.

    1996-05-01

    Substantial radio-frequency power in the ion-cyclotron range of frequencies can be effectively coupled to a tokamak plasma from poloidal current strap antennas at the plasma edge. If there exists an ion-ion hybrid resonance inside the plasma, then some of the power from the antenna, delivered into the plasma by fast Alfvén waves, can be mode converted to ion-Bernstein waves. In tokamak confinement fields the mode-converted ion-Bernstein waves can damp effectively and locally on electrons [A. K. Ram and A. Bers, Phys. Fluids B 3, 1059 (1991)]. The usual mode-conversion analysis that studies the propagation of fast Alfvén waves in the immediate vicinity of the ion-ion hybrid resonance is extended to include the propagation and reflection of the fast Alfvén waves on the high magnetic-field side of the ion-ion hybrid resonance. It is shown that there exist plasma conditions for which the entire fast Alfvén wave power incident on the ion-ion hybrid resonance can be converted to ion-Bernstein waves. In this extended analysis of the mode conversion process, the fast Alfvén waves can be envisioned as being coupled to an internal plasma resonator. This resonator extends from the low magnetic-field cutoff near the ion-ion hybrid resonance to the high magnetic-field cutoff. The condition for 100% mode conversion corresponds to a critical coupling of the fast Alfvén waves to this internal resonator. As an example, the appropriate plasma conditions for 100% mode conversion are determined for the Tokamak Fusion Test Reactor (TFTR) [R. Majeski et al., Proceedings of the 11th Topical Conference on RF Power in Plasmas, Palm Springs (American Institute of Physics, New York, 1995), Vol. 355, p. 63] experimental parameters.

  11. Energy Conversion Loop: A Testbed for Nuclear Hybrid Energy Systems Use in Biomass Pyrolysis

    NASA Astrophysics Data System (ADS)

    Verner, Kelley M.

    Nuclear hybrid energy systems are a possible solution for contemporary energy challenges. Nuclear energy produces electricity without greenhouse gas emissions. However, nuclear power production is not as flexible as electrical grids demand and renewables create highly variable electricity. Nuclear hybrid energy systems are able to address both of these problems. Wasted heat can be used in processes such as desalination, hydrogen production, or biofuel production. This research explores the possible uses of nuclear process heat in bio-oil production via biomass pyrolysis. The energy conversion loop is a testbed designed and built to mimic the heat from a nuclear reactor. Small scale biomass pyrolysis experiments were performed and compared to results from the energy conversion loop tests to determine future pyrolysis experimentation with the energy conversion loop. Further improvements must be made to the energy conversion loop before more complex experiments may be performed. The current conditions produced by the energy conversion loop are not conducive for current biomass pyrolysis experimentation.tion.

  12. Photovoltaic nanocrystal scintillators hybridized on Si solar cells for enhanced conversion efficiency in UV.

    PubMed

    Mutlugun, Evren; Soganci, Ibrahim Murat; Demir, Hilmi Volkan

    2008-03-17

    We propose and demonstrate semiconductor nanocrystal based photovoltaic scintillators integrated on solar cells to enhance photovoltaic device parameters including spectral responsivity, open circuit voltage, short circuit current, fill factor, and solar conversion efficiency in the ultraviolet. Hybridizing (CdSe)ZnS core-shell quantum dots of 2.4 nm in diameter on multi-crystalline Si solar cells for the first time, we show that the solar conversion efficiency is enhanced 2 folds under white light illumination similar to the solar spectrum. Such nanocrystal scintillators provide the ability to extend the photovoltaic activity towards UV.

  13. Polymer/Graphene Hybrids for Advanced Energy-Conversion and -Storage Materials.

    PubMed

    Cui, Linfan; Gao, Jian; Xu, Tong; Zhao, Yang; Qu, Liangti

    2016-04-20

    Polymer/graphene-based materials with interesting physical and chemical properties have been attracting considerable attention and have been shown to have great potential as active materials in the field of energy conversion and storage. In this review, we focus on recent significant advances in the fabrication and application of polymer/graphene hybrids as electrocatalysts and electrode materials. Synthetic strategies and application of these materials in energy conversion and storage are presented, particularly in devices such as fuel cells, actuators, and supercapacitors, accompanied with a discussion of the challenges and research directions necessary for the future development of polymer/graphene hybrids. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Reversible conversion of dominant polarity in ambipolar polymer/graphene oxide hybrids

    DOE PAGES

    Zhou, Ye; Han, Su -Ting; Sonar, Prashant; ...

    2015-03-24

    The possibility to selectively modulate the charge carrier transport in semiconducting materials is extremely challenging for the development of high performance and low-power consuming logic circuits. Systematical control over the polarity (electrons and holes) in transistor based on solution processed layer by layer polymer/graphene oxide hybrid system has been demonstrated. The conversion degree of the polarity is well controlled and reversible by trapping the opposite carriers. Basically, an electron device is switched to be a hole only device or vice versa. Finally, a hybrid layer ambipolar inverter is demonstrated in which almost no leakage of opposite carrier is found. Wemore » conclude that this hybrid material has wide range of applications in planar p-n junctions and logic circuits for high-throughput manufacturing of printed electronic circuits.« less

  15. Reversible conversion of dominant polarity in ambipolar polymer/graphene oxide hybrids

    SciTech Connect

    Zhou, Ye; Han, Su -Ting; Sonar, Prashant; Ma, Xinlei; Chen, Jihua; Zheng, Zijian; Roy, V. A. L.

    2015-03-24

    The possibility to selectively modulate the charge carrier transport in semiconducting materials is extremely challenging for the development of high performance and low-power consuming logic circuits. Systematical control over the polarity (electrons and holes) in transistor based on solution processed layer by layer polymer/graphene oxide hybrid system has been demonstrated. The conversion degree of the polarity is well controlled and reversible by trapping the opposite carriers. Basically, an electron device is switched to be a hole only device or vice versa. Finally, a hybrid layer ambipolar inverter is demonstrated in which almost no leakage of opposite carrier is found. We conclude that this hybrid material has wide range of applications in planar p-n junctions and logic circuits for high-throughput manufacturing of printed electronic circuits.

  16. Reversible Conversion of Dominant Polarity in Ambipolar Polymer/Graphene Oxide Hybrids

    PubMed Central

    Zhou, Ye; Han, Su-Ting; Sonar, Prashant; Ma, Xinlei; Chen, Jihua; Zheng, Zijian; Roy, V. A. L.

    2015-01-01

    The possibility to selectively modulate the charge carrier transport in semiconducting materials is extremely challenging for the development of high performance and low-power consuming logic circuits. Systematical control over the polarity (electrons and holes) in transistor based on solution processed layer by layer polymer/graphene oxide hybrid system has been demonstrated. The conversion degree of the polarity is well controlled and reversible by trapping the opposite carriers. Basically, an electron device is switched to be a hole only device or vice versa. Finally, a hybrid layer ambipolar inverter is demonstrated in which almost no leakage of opposite carrier is found. This hybrid material has wide range of applications in planar p-n junctions and logic circuits for high-throughput manufacturing of printed electronic circuits. PMID:25801827

  17. Hexagonal mesoporous titanium tetrasulfonates with large conjugated hybrid framework for photoelectric conversion.

    PubMed

    Ma, Tian-Yi; Wei, Yan-Shuang; Ren, Tie-Zhen; Liu, Lei; Guo, Qiang; Yuan, Zhong-Yong

    2010-12-01

    Ordered hexagonal mesoporous titanium tetrasulfonate materials (CuPcS4-Ti) were synthesized through a hydrothermal process with the assistance of surfactant F127, by using the copper(II) phthalocyanine-tetrasulfonic acid tetrasodium salt (CuPcS4) as coupling molecules. It was confirmed by TEM, IR, UV-vis, TGA-DSC, and XRD analysis that the CuPcS4 groups were homogenously incorporated into the hybrid framework, and the synthesized materials could be stable to around 328 °C with the hybrid framework and ordered mesopores well-preserved. A high dye content of Ti/CuPcS4 molar ratio at around 50 was achieved, which could be useful in the photoelectric conversion applications. A novel model of isolated dye centers surrounded by semiconductor oligomers was set, which could effectively suppress the aggregation of dye molecules that may decrease the conversion efficiency in some traditional dye-sensitized solar cells. It was proved that the synthesized CuPcS4-Ti exhibited a relatively high conversion efficiency of 0.53%. It was very valuable to access such a high conversion efficiency by using low-cost and commercially available dye molecules instead of using the expensive unsymmetrical phthalocyanines synthesized by the time-consuming methods in the literature.

  18. Restoration of the Conversion of Desmosterol to Cholesterol in L-Cells after Hybridization with Human Fibroblasts

    PubMed Central

    Croce, C. M.; Kieba, I.; Koprowski, H.; Molino, M.; Rothblat, G. H.

    1974-01-01

    Hybrids between different human cells (which synthesize cholesterol) and mouse cells (whose end-product of sterol synthesis is desmosterol) were analyzed for the ability to convert desmosterol to cholesterol. Conversion of [14C]desmosterol to cholesterol and incorporation of [14C]acetate into the end-product sterol were studied in the parental and hybrid cells. Concordant segregation of the conversion of desmosterol to cholesterol and the human chromosome F-20 was observed. Images PMID:4359325

  19. A parameter study of mode conversion at ion-ion hybrid resonances for ICRF-heating

    NASA Astrophysics Data System (ADS)

    Alava, M. J.; Heikkinen, J. A.

    1992-04-01

    By solving the wave equation for the radial electric field with constant poloidal electric field around the resonance layer of the fast Alfvén wave, various complex characteristics of mode conversion physics can be elucidated and analyzed for ion cyclotron heating of tokamaks. The validity of the Budden and tunnelling model [Ngan, Y. C. and Swanson, D. G., Phys. Fluids 20, 1920 (1977)] for the conversion studies is explored, and the conversion coefficient for the ion-ion hybrid resonance in the presence of cyclotron damping is found in closed form. The analytical results are compared with the numerical solution of the full wave equations expanded to second order in ion Larmor radius. It is found that the standard tunnelling solutions can be erroneous, not only in the case of strong damping, but also when the linearization of the plasma parameters around the resonance, peculiar to the tunnelling model, becomes inaccurate. The effects of the damping and cavity resonances on the conversion are separated in the derived analytical estimates, and the limits of the local theory of conversion are determined.

  20. Magnetic flux conversion in the DIII-D high-beta hybrid scenario

    NASA Astrophysics Data System (ADS)

    Taylor, N. Z.; Luce, T. C.; La Haye, R. J.; Petty, C. C.; Piovesan, P.

    2016-10-01

    In DIII-D hybrid scenario discharges, the rate of poloidal magnetic energy consumption is more than the rate of energy flow from the poloidal field coils. This is evidence that there is a conversion of toroidal flux to poloidal flux, which may account for a process known as flux pumping that leads to anomalous broadening of the current profile. The hybrid is a promising high confinement scenario for ITER. The broader current profile aids discharge sustainment by raising the minimum safety factor above unity thereby avoiding sawtooth-triggered 2/1 tearing modes that spoil energy confinement. During long ( 1.5s) stationary intervals with constant stored magnetic energy, a significant flux state deficit rate >10 mV was observed. This anomalous consumption of poloidal flux only occurred in discharges with βN > 2.5 and when a relatively benign 3/2 tearing mode was present. This suggests the tearing mode plays a critical role in flux conversion. Studies have shown that 3D core displacements can lead to flux conversion, suggesting that the 3/2 tearing mode and its 2/2 side band produce helical perturbations in the core velocity and magnetic field capable of producing a dynamo EMF that drives the observed current redistribution. Supported by the US DOE under DE-AC05-06OR23100 and DE-FC02-04ER54698.

  1. Thermodynamic limits for solar energy conversion by a quantum-thermal hybrid system

    NASA Astrophysics Data System (ADS)

    Byvik, C. E.; Buoncristiani, A. M.; Smith, B. T.

    1981-11-01

    The limits are presented fo air mass 1.5 conditions. A maximum conversion efficiency of 74 percent is thermodynamically achievable for the quantum device operating at 3500 K and the heat engine in contact with a reservoir at 0 K. The efficiency drops to 56 percent for a cold reservoir at approximately room temperature conditions. Hybrid system efficiencies exceed 50 percent over receiver temperatures ranging from 1400 K to 4000 K, suggesting little benefit is gained in operating the system above 1400 K. The results are applied to a system consisting of a photovoltaic solar cell in series with a heat engine.

  2. Thermodynamic limits for solar energy conversion by a quantum-thermal hybrid system

    NASA Technical Reports Server (NTRS)

    Byvik, C. E.; Buoncristiani, A. M.; Smith, B. T.

    1981-01-01

    The limits are presented fo air mass 1.5 conditions. A maximum conversion efficiency of 74 percent is thermodynamically achievable for the quantum device operating at 3500 K and the heat engine in contact with a reservoir at 0 K. The efficiency drops to 56 percent for a cold reservoir at approximately room temperature conditions. Hybrid system efficiencies exceed 50 percent over receiver temperatures ranging from 1400 K to 4000 K, suggesting little benefit is gained in operating the system above 1400 K. The results are applied to a system consisting of a photovoltaic solar cell in series with a heat engine.

  3. Inorganic Nanoparticles/Metal Organic Framework Hybrid Membrane Reactors for Efficient Photocatalytic Conversion of CO2.

    PubMed

    Maina, James W; Schütz, Jürg A; Grundy, Luke; Des Ligneris, Elise; Yi, Zhifeng; Kong, Lingxue; Pozo-Gonzalo, Cristina; Ionescu, Mihail; Dumée, Ludovic F

    2017-09-29

    Photocatalytic conversion of carbon dioxide (CO2) to useful products has potential to address the adverse environmental impact of global warming. However, most photocatalysts used to date exhibit limited catalytic performance, due to poor CO2 adsorption capacity, inability to efficiently generate photoexcited electrons, and/or poor transfer of the photogenerated electrons to CO2 molecules adsorbed on the catalyst surface. The integration of inorganic semiconductor nanoparticles across metal organic framework (MOF) materials has potential to yield new hybrid materials, combining the high CO2 adsorption capacity of MOF and the ability of the semiconductor nanoparticles to generate photoexcited electrons. Herein, controlled encapsulation of TiO2 and Cu-TiO2 nanoparticles within zeolitic imidazolate framework (ZIF-8) membranes was successfully accomplished, using rapid thermal deposition (RTD), and their photocatalytic efficiency toward CO2 conversion was investigated under UV irradiation. Methanol and carbon monoxide (CO) were found to be the only products of the CO2 reduction, with yields strongly dependent upon the content and composition of the dopant semiconductor particles. CuTiO2 nanoparticle doped membranes exhibited the best photocatalytic performance, with 7 μg of the semiconductor nanoparticle enhancing CO yield of the pristine ZIF-8 membrane by 233%, and methanol yield by 70%. This work opens new routes for the fabrication of hybrid membranes containing inorganic nanoparticles and MOFs, with potential application not only in catalysis but also in electrochemical, separation, and sensing applications.

  4. Hybridizing Conversational and Clear Speech to Investigate the Source of Increased Intelligibility in Speakers With Parkinson’s Disease

    PubMed Central

    Tjaden, Kris; Kain, Alexander; Lam, Jennifer

    2017-01-01

    Purpose A speech analysis-resynthesis paradigm was used to investigate segmental and suprasegmental acoustic variables explaining intelligibility variation for 2 speakers with Parkinson’s disease (PD). Method Sentences were read in conversational and clear styles. Acoustic characteristics from clear sentences were extracted and applied to conversational sentences, yielding 6 hybridized versions of sentences in which segment durations, short-term spectrum, energy characteristics, or fundamental frequency characteristics for clear productions were applied individually or in combination to conversational productions. Listeners (N = 20) judged intelligibility in transcription and scaling tasks. Results Intelligibility increases above conversation were more robust for transcription, but the pattern of intelligibility improvement was similar across tasks. For 1 speaker, hybridization involving only clear energy characteristics yielded an 8.7% improvement in transcription intelligibility above conversation. For the other speaker, hybridization involving clear spectrum yielded an 18% intelligibility improvement, whereas hybridization involving both clear spectrum and duration yielded a 13.4% improvement. Conclusions Not all production changes accompanying clear speech explain its improved intelligibility. Suprasegmental adjustments contributed to intelligibility improvements when segmental adjustments, as inferred from vowel space area, were not robust. Hybridization can be used to identify acoustic variables explaining intelligibility variation in mild dysarthria secondary to PD. PMID:24686409

  5. Hybrid photovoltaic-thermoelectric system for concentrated solar energy conversion: Experimental realization and modeling

    NASA Astrophysics Data System (ADS)

    Beeri, Ofer; Rotem, Oded; Hazan, Eden; Katz, Eugene A.; Braun, Avi; Gelbstein, Yaniv

    2015-09-01

    An experimental demonstration of the combined photovoltaic (PV) and thermoelectric conversion of concentrated sunlight (with concentration factor, X, up to ˜300) into electricity is presented. The hybrid system is based on a multi-junction PV cell and a thermoelectric generator (TEG). The latter increases the electric power of the system and dissipates some of the excessive heat. For X ≤ 200, the system's maximal efficiency, ˜32%, was mostly due to the contribution from the PV cell. With increasing X and system temperature, the PV cell's efficiency decreased while that of the TEG increased. Accordingly, the direct electrical contribution of the TEG started to dominate in the total system power, reaching ˜20% at X ≈ 290. Using a simple steady state finite element modeling, the cooling effect of the TEG on the hybrid system's efficiency was proved to be even more significant than its direct electrical contribution for high solar concentrations. As a result, the total efficiency contribution of the TEG reached ˜40% at X ≈ 200. This suggests a new system optimization concept that takes into account the PV cell's temperature dependence and the trade-off between the direct electrical generation and cooling capabilities of the TEG. It is shown that the hybrid system has a real potential to exceed 50% total efficiency by using more advanced PV cells and TE materials.

  6. Squeezed mode conversion in hybrid plasmon polariton waveguide using spin-coated silver film.

    PubMed

    Ha, Thi-Vu-Anh; Park, Hae-Ryeong; Son, Jung-Han; Lee, Myung-Hyun

    2012-07-01

    We designed, fabricated, and characterized a hybrid surface plasmon polariton waveguide (SPP_wg) for mode conversion. The 20-nm-thick silver SPP_wg was fabricated via spin-coating with an aqueous silver ionic complex solution. The structure of the SPP_wg consists of a straight Insulator-Metal-Insulator waveguide (IMl_wg), a lateral tapered Insulator-Metal-Insulator-Metal-Insulator waveguide (tapered_IMIMI_wg), and a straight IMIMI waveguide (IMIMI_wg). An s0 mode size of 12.90 microm x 8.08 microm at a 6-microm-wide IMI_wg was excited by a butt-coupling method at a wavelength of 1550 nm. The s0 mode was converted into an Ss0 mode size of 8.08 microm x 5.65 microm at a 3-microm-wide IMIMI_wg. The mode size was squeezed by approximately 2/3 via a 15-microm-long lateral tapered_IMIMI_wg with a 500-nm-thick central insulator. The coupling loss for mode conversion between the straight IMI_wg and the straight IMIMI_wg was 5.49 dB. The hybrid SPP_wg for mode conversion has the potential to bridge the gap between micron and sub-micron scales in nano plasmonic integrated circuits. In addition, the use of the spin coating method is very cost-effective because films are formed at a low temperature in a short period of time without the need for a vacuum system.

  7. Global particle simulation of lower hybrid wave propagation and mode conversion in tokamaks

    SciTech Connect

    Bao, J.; Lin, Z.; Kuley, A.

    2015-12-10

    Particle-in-cell simulation of lower hybrid (LH) waves in core plasmas is presented with a realistic electron-to-ion mass ratio in toroidal geometry. Due to the fact that LH waves mainly interact with electrons to drive the current, ion dynamic is described by cold fluid equations for simplicity, while electron dynamic is described by drift kinetic equations. This model could be considered as a new method to study LH waves in tokamak plasmas, which has advantages in nonlinear simulations. The mode conversion between slow and fast waves is observed in the simulation when the accessibility condition is not satisfied, which is consistent with the theory. The poloidal spectrum upshift and broadening effects are observed during LH wave propagation in the toroidal geometry.

  8. Thin-Film Multilayer Filter Designs For Hybrid Solar Energy Conversion Systems

    NASA Astrophysics Data System (ADS)

    DeSandre, L.; Song, D. Y.; Macleod, H. A.; Jacobson, M. R.; Osborn, D. E.

    1985-12-01

    The efficiency of hybrid photothermal/photovoltaic energy conversion can be increased by separating the solar spectrum into portions matched to the photothermal and photovoltaic processes. Thin-film multilayer filters can implement this concept; five such filters consisting of all-dielectric or metal-dielectric layers have been designed. The transmission profile of each design is calculated by computer, considering dispersion, absorption, and angle of incidence effects. These profiles are compared and evaluated with respect to the desired spectral performance. The most successful candidate design is an optical minus filter consisting of Ti02, Zr02, and Si02. Results show very sharp selection of the targeted photovoltaic spectral region and low ripple in the transmission region outside the bandstop.

  9. Carbon nanotube-amorphous silicon hybrid solar cell with improved conversion efficiency.

    PubMed

    Funde, Adinath M; Nasibulin, Albert G; Syed, Hashmi Gufran; Anisimov, Anton S; Tsapenko, Alexey; Lund, Peter; Santos, J D; Torres, I; Gandía, J J; Cárabe, J; Rozenberg, A D; Levitsky, Igor A

    2016-05-06

    We report a hybrid solar cell based on single walled carbon nanotubes (SWNTs) interfaced with amorphous silicon (a-Si). The high quality carbon nanotube network was dry transferred onto intrinsic a-Si forming Schottky junction for metallic SWNT bundles and heterojunctions for semiconducting SWNT bundles. The nanotube chemical doping and a-Si surface treatment minimized the hysteresis effect in current-voltage characteristics allowing an increase in the conversion efficiency to 1.5% under an air mass 1.5 solar spectrum simulator. We demonstrated that the thin SWNT film is able to replace a simultaneously p-doped a-Si layer and transparent conductive electrode in conventional amorphous silicon thin film photovoltaics.

  10. Somatic generation of hybrid antibody H chain genes in transgenic mice via interchromosomal gene conversion

    PubMed Central

    1994-01-01

    We have constructed lines of mice with transgenes containing an antibody heavy (H) chain variable region (VHDJH) gene and various amounts of natural immunoglobulin (Ig) and plasmid flanking DNA. In these lines, recombination of the transgene and the endogenous Igh locus takes place in B cells, leading to the expression of functional H chains partially encoded by the transgenic VHDJH gene. Here, we demonstrate that the transgenic VHDJH gene, and various amounts of flanking sequence are recombined with Igh locus DNA via interchromosomal gene conversion. The structures of the resulting "hybrid" transgene-Igh H chain loci are consistent with the 3' end of the conversion occurring in regions of sequence identity, and the 5' end taking place between regions of little or no homology. This mode of antibody transgene recombination with the Igh locus is fundamentally different from the previously reported "trans H chain class switching" that results in reciprocal translocations. In contrast, this recombination resembles events previously observed in mammalian tissue culture cells between adjacent homologous chromosomal sequences, or transfected DNA and a homologous chromosomal target. Our data indicate that this recombination takes place at a low frequency, and that the frequency is influenced by both the length and extent of homology between the transgene and the Igh locus, but is not greatly affected by transgene copy number. This recombination pathway provides a novel approach for the subtle alteration of the clonal composition of the mouse B cell compartment in vivo using VH genes with defined structures and functions. PMID:8270869

  11. Hybrid chromophore/template nanostructures: a customizable platform material for solar energy storage and conversion.

    PubMed

    Kolpak, Alexie M; Grossman, Jeffrey C

    2013-01-21

    Challenges with cost, cyclability, and/or low energy density have largely prevented the development of solar thermal fuels, a potentially attractive alternative energy technology based on molecules that can capture and store solar energy as latent heat in a closed cycle. In this paper, we present a set of novel hybrid photoisomer/template solar thermal fuels that can potentially circumvent these challenges. Using first-principles computations, we demonstrate that these fuels, composed of organic photoisomers bound to inexpensive carbon-based templates, can reversibly store solar energy at densities comparable to Li-ion batteries. Furthermore, we show that variation of the template material in combination with the photoisomer can be used to optimize many of the key performance metrics of the fuel-i.e., the energy density, the storage lifetime, the temperature of the output heat, and the efficiency of the solar-to-heat conversion. Our work suggests that the solar thermal fuels concept can be translated into a practical and highly customizable energy storage and conversion technology.

  12. Analysis Of Spectrally Selective Liquid Absorption Filters For Hybrid Solar Energy Conversion

    NASA Astrophysics Data System (ADS)

    Chendo, M. A. C.; Osborn, D. E.; Swenson, Rick

    1985-12-01

    Various techniques have been proposed to convert solar energy to both electric power and heat in hybrid systems. Many of these approaches are designed to utilize spectral selectivity to improve the overall conversion efficiency. Examples include spectrally selective beamsplitters and arrangements of long-wave or short-wave-pass glass filters that divide the spectrum so that photon energies are roughly matched to the energies corresponding to the solar-cell bandgaps or to efficient photothermal convertors. This paper describes the analysis of liquid optical filters that have high transmittance in the visible spectrum and high absorptance in the infrared. These qualities make it possible to capture that portion of the spectrum useful to a quantum convertor, such as a photovoltaic cell, while channeling the "excess heat" of the photons with energies below the bandgap to a thermal convertor, thereby enhancing the overall conversion efficiency of the system. The preliminary studies show that spectral responses of the tested solutions (salts in water) are primarily influenced by the cation component of the salt solution. By changing the solutions and concentrations, a variety of spectrally selective filters can be tailored to match system requirements.

  13. Lamb mode conversion at edges. A hybrid boundary element-finite-element solution.

    PubMed

    Galán, José M; Abascal, Ramón

    2005-04-01

    Two general and flexible numerical techniques based on the finite-element and boundary element methods developed by the authors in a previous paper are applied to study Lamb wave propagation in multilayered plates and Lamb mode conversion at free edges for frequencies beyond the first cutoff frequency. Both techniques are supported by a meshing criterion which guarantees the accuracy of the results when a condition is fulfilled. A finite-element formulation is directly applicable to study Lamb wave propagation and reflection by simple obstacles such as a flat edge. In order to tackle Lamb wave diffraction problems by defects with more complex geometries, a hybrid boundary element-finite-element formulation is used. This technique provides a major improvement with respect to the only previous boundary element application on Lamb waves: the connecting boundary might be placed as close to the reflector as desired, reducing greatly the requirement on mesh size. Two main application problems on practical metallic plates are studied and compared with reported numerical, theoretical, and experimental results: (1) Lamb wave propagation in degraded titanium diffusion bonds, and (2) Lamb mode conversion at inclined or perpendicular free edges of steel plates for frequencies beyond the first cutoff frequency.

  14. Hybrid chromophore/template nanostructures: A customizable platform material for solar energy storage and conversion

    SciTech Connect

    Kolpak, AM; Grossman, JC

    2013-01-21

    Challenges with cost, cyclability, and/or low energy density have largely prevented the development of solar thermal fuels, a potentially attractive alternative energy technology based on molecules that can capture and store solar energy as latent heat in a closed cycle. In this paper, we present a set of novel hybrid photoisomer/template solar thermal fuels that can potentially circumvent these challenges. Using first-principles computations, we demonstrate that these fuels, composed of organic photoisomers bound to inexpensive carbon-based templates, can reversibly store solar energy at densities comparable to Li-ion batteries. Furthermore, we show that variation of the template material in combination with the photoisomer can be used to optimize many of the key performance metrics of the fuel-i.e., the energy density, the storage lifetime, the temperature of the output heat, and the efficiency of the solar-to-heat conversion. Our work suggests that the solar thermal fuels concept can be translated into a practical and highly customizable energy storage and conversion technology. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4773306

  15. Hybrid chromophore/template nanostructures: A customizable platform material for solar energy storage and conversion

    NASA Astrophysics Data System (ADS)

    Kolpak, Alexie M.; Grossman, Jeffrey C.

    2013-01-01

    Challenges with cost, cyclability, and/or low energy density have largely prevented the development of solar thermal fuels, a potentially attractive alternative energy technology based on molecules that can capture and store solar energy as latent heat in a closed cycle. In this paper, we present a set of novel hybrid photoisomer/template solar thermal fuels that can potentially circumvent these challenges. Using first-principles computations, we demonstrate that these fuels, composed of organic photoisomers bound to inexpensive carbon-based templates, can reversibly store solar energy at densities comparable to Li-ion batteries. Furthermore, we show that variation of the template material in combination with the photoisomer can be used to optimize many of the key performance metrics of the fuel—i.e., the energy density, the storage lifetime, the temperature of the output heat, and the efficiency of the solar-to-heat conversion. Our work suggests that the solar thermal fuels concept can be translated into a practical and highly customizable energy storage and conversion technology.

  16. Construction of hybrid Chinese reference adult phantoms and estimation of dose conversion coefficients for muons.

    PubMed

    Dong, Liang; Li, Taosheng; Liu, Chunyu

    2015-04-01

    A set of fluence-to-effective dose conversion coefficients of external exposure to muons were investigated for Chinese hybrid phantom references, which include both male and female. Both polygon meshes and Non-Uniform Rational B-Spline (NURBS) surfaces were used to descried the boundary of the organs and tissues in these phantoms. The 3D-DOCTOR and Rhinoceros software were used to polygonise the colour slice images and generate the NURBS surfaces, respectively. The voxelisation is completed using the BINVOX software and the assembly finished by using MATLAB codes. The voxel resolutions were selected to be 0.22 × 0.22 × 0.22 cm(3) and 0.2 × 0.2 × 0.2 cm(3) for male and female phantoms, respectively. All parts of the final phantoms were matched to their reference organ masses within a tolerance of ±5%. The conversion coefficients for negative and positive muons were calculated with the FLUKA transport code. There were 21 external monoenergetic beams ranging from 0.01 GeV to 100 TeV in 5 different geometrical conditions of irradiation.

  17. A preliminary study on improving the recognition of esophageal speech using a hybrid system based on statistical voice conversion.

    PubMed

    Lachhab, Othman; Di Martino, Joseph; Elhaj, Elhassane Ibn; Hammouch, Ahmed

    2015-01-01

    In this paper, we propose a hybrid system based on a modified statistical GMM voice conversion algorithm for improving the recognition of esophageal speech. This hybrid system aims to compensate for the distorted information present in the esophageal acoustic features by using a voice conversion method. The esophageal speech is converted into a "target" laryngeal speech using an iterative statistical estimation of a transformation function. We did not apply a speech synthesizer for reconstructing the converted speech signal, given that the converted Mel cepstral vectors are used directly as input of our speech recognition system. Furthermore the feature vectors are linearly transformed by the HLDA (heteroscedastic linear discriminant analysis) method to reduce their size in a smaller space having good discriminative properties. The experimental results demonstrate that our proposed system provides an improvement of the phone recognition accuracy with an absolute increase of 3.40 % when compared with the phone recognition accuracy obtained with neither HLDA nor voice conversion.

  18. Designing interfaces of hydrogenase-nanomaterial hybrids for efficient solar conversion.

    PubMed

    King, Paul W

    2013-01-01

    The direct conversion of sunlight into biofuels is an intriguing alternative to a continued reliance on fossil fuels. Natural photosynthesis has long been investigated both as a potential solution, and as a model for utilizing solar energy to drive a water-to-fuel cycle. The molecules and organizational structure provide a template to inspire the design of efficient molecular systems for photocatalysis. A clear design strategy is the coordination of molecular interactions that match kinetic rates and energetic levels to control the direction and flow of energy from light harvesting to catalysis. Energy transduction and electron-transfer reactions occur through interfaces formed between complexes of donor-acceptor molecules. Although the structures of several of the key biological complexes have been solved, detailed descriptions of many electron-transfer complexes are lacking, which presents a challenge to designing and engineering biomolecular systems for solar conversion. Alternatively, it is possible to couple the catalytic power of biological enzymes to light harvesting by semiconductor nanomaterials. In these molecules, surface chemistry and structure can be designed using ligands. The passivation effect of the ligand can also dramatically affect the photophysical properties of the semiconductor, and energetics of external charge-transfer. The length, degree of bond saturation (aromaticity), and solvent exposed functional groups of ligands can be manipulated to further tune the interface to control molecular assembly, and complex stability in photocatalytic hybrids. The results of this research show how ligand selection is critical to designing molecular interfaces that promote efficient self-assembly, charge-transfer and photocatalysis. This article is part of a Special Issue entitled: Metals in Bioenergetics and Biomimetics Systems.

  19. Synthesis of nanoporous carbon-cobalt-oxide hybrid electrocatalysts by thermal conversion of metal-organic frameworks.

    PubMed

    Chaikittisilp, Watcharop; Torad, Nagy L; Li, Cuiling; Imura, Masataka; Suzuki, Norihiro; Ishihara, Shinsuke; Ariga, Katsuhiko; Yamauchi, Yusuke

    2014-04-07

    Nanoporous carbon-cobalt-oxide hybrid materials are prepared by a simple, two-step, thermal conversion of a cobalt-based metal-organic framework (zeolitic imidazolate framework-9, ZIF-9). ZIF-9 is carbonized in an inert atmosphere to form nanoporous carbon-metallic-cobalt materials, followed by the subsequent thermal oxidation in air, yielding nanoporous carbon-cobalt-oxide hybrids. The resulting hybrid materials are evaluated as electrocatalysts for the oxygen-reduction reaction (ORR) and the oxygen-evolution reaction (OER) in a KOH electrolyte solution. The hybrid materials exhibit similar catalytic activity in the ORR to the benchmark, commercial, Pt/carbon black catalyst, and show better catalytic activity for the OER than the Pt-based catalyst. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. 3D graphene-based hybrid materials: synthesis and applications in energy storage and conversion.

    PubMed

    Shi, Qiurong; Cha, Younghwan; Song, Yang; Lee, Jung-In; Zhu, Chengzhou; Li, Xiaoyu; Song, Min-Kyu; Du, Dan; Lin, Yuehe

    2016-08-25

    Porous 3D graphene-based hybrid materials (3D GBHMs) are currently attractive nanomaterials employed in the field of energy. Heteroatom-doped 3D graphene and metal, metal oxide, and polymer-decorated 3D graphene with modified electronic and atomic structures provide promising performance as electrode materials in energy storage and conversion. Numerous synthesis methods such as self-assembly, templating, electrochemical deposition, and supercritical CO2, pave the way to mass production of 3D GBHMs in the commercialization of energy devices. This review summarizes recent advances in the fabrication of 3D GBHMs with well-defined architectures such as finely controlled pore sizes, heteroatom doping types and levels. Moreover, current progress toward applications in fuel cells, supercapacitors and batteries employing 3D GBHMs is also highlighted, along with the detailed mechanisms of the enhanced electrochemical performance. Furthermore, current critical issues, challenges and future prospects with respect to applications of 3D GBHMs in practical devices are discussed at the end of this review.

  1. Seasonal variation in food consumption, assimilation, and conversion efficiency of Indian bivoltine hybrid silkworm, Bombyx mori.

    PubMed

    Rahmathulla, V K; Suresh, H M

    2012-01-01

    Food consumption and utilization is influenced by various biotic and abiotic factors. Under different environmental, feeding, and nutritional conditions, and with ingestion of the same amount of mulberry leaves, the silkworm shows significant difference in its ability to digest, absorb, and convert food to body matter. Here, influences of season, temperature, and humidity on food intake, assimilation, and conversion efficiency of the Indian bivoltine hybrid (CSR2 × CSR4) Bombyx mori L. (Lepidoptera: Bombycidae) were studied. The results indicated that food ingestion and assimilation were significantly higher among silkworm batches where optimum temperature and humidity were maintained compared with silkworm batches exposed to natural climatic conditions of the respective season. However, during summer the nutritional efficiency parameters were significantly higher among silkworms reared under natural temperature and humidity conditions when compared with the control. During the winter and rainy season, the nutritional efficiency parameters were significantly higher in control batches, where optimum temperature and humidity were maintained. Ingesta and digesta required to produce one gram of cocoon/shell were also lower in control batches for all seasons except summer. This may be due to the physiological adaptation of silkworms to overcome stress during the summer season.

  2. Seasonal Variation in Food Consumption, Assimilation, and Conversion Efficiency of Indian Bivoltine Hybrid Silkworm, Bombyx mori

    PubMed Central

    Rahmathulla, V. K.; Suresh, H. M.

    2012-01-01

    Food consumption and utilization is influenced by various biotic and abiotic factors. Under different environmental, feeding, and nutritional conditions, and with ingestion of the same amount of mulberry leaves, the silkworm shows significant difference in its ability to digest, absorb, and convert food to body matter. Here, influences of season, temperature, and humidity on food intake, assimilation, and conversion efficiency of the Indian bivoltine hybrid (CSR2 × CSR4) Bombyx mori L. (Lepidoptera: Bombycidae) were studied. The results indicated that food ingestion and assimilation were significantly higher among silkworm batches where optimum temperature and humidity were maintained compared with silkworm batches exposed to natural climatic conditions of the respective season. However, during summer the nutritional efficiency parameters were significantly higher among silkworms reared under natural temperature and humidity conditions when compared with the control. During the winter and rainy season, the nutritional efficiency parameters were significantly higher in control batches, where optimum temperature and humidity were maintained. Ingesta and digesta required to produce one gram of cocoon/shell were also lower in control batches for all seasons except summer. This may be due to the physiological adaptation of silkworms to overcome stress during the summer season. PMID:23414194

  3. Plasmon-mediated Energy Conversion in Metal Nanoparticle-doped Hybrid Nanomaterials

    NASA Astrophysics Data System (ADS)

    Dunklin, Jeremy R.

    Climate change and population growth demand long-term solutions for clean water and energy. Plasmon-active nanomaterials offer a promising route towards improved energetics for efficient chemical separation and light harvesting schemes. Two material platforms featuring highly absorptive plasmonic gold nanoparticles (AuNPs) are advanced herein to maximize photon conversion into thermal or electronic energy. Optical extinction, attributable to diffraction-induced internal reflection, was enhanced up to 1.5-fold in three-dimensional polymer films containing AuNPs at interparticle separations approaching the resonant wavelength. Comprehensive methods developed to characterize heat dissipation following plasmonic absorption was extended beyond conventional optical and heat transfer descriptions, where good agreement was obtained between measured and estimated thermal profiles for AuNP-polymer dispersions. Concurrently, in situ reduction of AuNPs on two-dimensional semiconducting tungsten disulfide (WS2) addressed two current material limitations for efficient light harvesting: low monolayer content and lack of optoelectronic tunability. Order-of-magnitude increases in WS2 monolayer content, enhanced broadband optical extinction, and energetic electron injection were probed using a combination of spectroscopic techniques and continuum electromagnetic descriptions. Together, engineering these plasmon-mediated hybrid nanomaterials to facilitate local exchange of optical, thermal, and electronic energy supports design and implementation into several emerging sustainable water and energy applications.

  4. Hybrid micro-/nano-structures derived from metal-organic frameworks: preparation and applications in energy storage and conversion.

    PubMed

    Cao, Xiehong; Tan, Chaoliang; Sindoro, Melinda; Zhang, Hua

    2017-05-22

    Metal-organic frameworks (MOFs), an important class of inorganic-organic hybrid crystals with intrinsic porous structures, can be used as versatile precursors or sacrificial templates for preparation of numerous functional nanomaterials for various applications. Recent developments of MOF-derived hybrid micro-/nano-structures, constructed by more than two components with varied functionalities, have revealed their extensive capabilities to overcome the weaknesses of the individual counterparts and thus give enhanced performance for energy storage and conversion. In this tutorial review, we summarize the recent advances in MOF-derived hybrid micro-/nano-structures. The synthetic strategies for preparing MOF-derived hybrid micro-/nano-structures are first introduced. Focusing on energy storage and conversion, we then discuss their potential applications in lithium-ion batteries, lithium-sulfur batteries, supercapacitors, lithium-oxygen batteries and fuel cells. Finally, we give our personal insights into the challenges and opportunities for the future research of MOF-derived hybrid micro-/nano-structures.

  5. Design of hybrid nanoheterostructure systems for enhanced quantum and solar conversion efficiencies in dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Kılıç, Bayram; Telli, Hakan; Tüzemen, Sebahattin; Başaran, Ali; Pirge, Gursev

    2015-04-01

    Dye sensitized solar cells (DSSCs) with an innovative design involving controlled-morphology vertically aligned (VA) ZnO nanowires within mesoporous TiO2 structures with ultrahigh surface area for implementation as photoanodes are herein reported. Although TiO2 nanostructures exhibit excellent power conversion efficiency, the electron transport rate is low owing to low electron mobility. To overcome this, ZnO nanowires with high electron mobility have been investigated as potential candidates for photoanodes. However, the power conversion efficiency of ZnO nanowires is still lower than that of TiO2 owing to their low internal surface area. Consequently, in this work, vertical growth of ZnO nanowires within mesoporous TiO2 structures is carried out to increase their solar power conversion efficiency. The photovoltaic performance of solar cells using ZnO nanowires, mesoporous TiO2, and TiO2/ZnO hybrid structures are compared. The VA TiO2/ZnO hybrid structures are found to provide direct electron transfer compared with the tortuous pathway of zero-dimensional nanostructures, resulting in an increased conversion efficiency. It is demonstrated that the light scattering of the photoanode film is increased and electron recombination is decreased when an appropriate amount of mesoporous TiO2 is used as a substrate for ZnO nanowires. The DSSC fabricated with the TiO2/ZnO hybrid photoanode prepared with 15.8 wt. % TiO2 showed the highest conversion efficiency of 7.30%, approximately 5%, 18%, and 40% higher than that of DSSCs fabricated with 3.99 wt. % TiO2, pure TiO2, and pure ZnO photoanodes, respectively.

  6. Design of hybrid nanoheterostructure systems for enhanced quantum and solar conversion efficiencies in dye-sensitized solar cells

    SciTech Connect

    Kılıç, Bayram E-mail: kbayramkilic@gmail.com; Telli, Hakan; Başaran, Ali; Pirge, Gursev; Tüzemen, Sebahattin

    2015-04-07

    Dye sensitized solar cells (DSSCs) with an innovative design involving controlled-morphology vertically aligned (VA) ZnO nanowires within mesoporous TiO{sub 2} structures with ultrahigh surface area for implementation as photoanodes are herein reported. Although TiO{sub 2} nanostructures exhibit excellent power conversion efficiency, the electron transport rate is low owing to low electron mobility. To overcome this, ZnO nanowires with high electron mobility have been investigated as potential candidates for photoanodes. However, the power conversion efficiency of ZnO nanowires is still lower than that of TiO{sub 2} owing to their low internal surface area. Consequently, in this work, vertical growth of ZnO nanowires within mesoporous TiO{sub 2} structures is carried out to increase their solar power conversion efficiency. The photovoltaic performance of solar cells using ZnO nanowires, mesoporous TiO{sub 2}, and TiO{sub 2}/ZnO hybrid structures are compared. The VA TiO{sub 2}/ZnO hybrid structures are found to provide direct electron transfer compared with the tortuous pathway of zero-dimensional nanostructures, resulting in an increased conversion efficiency. It is demonstrated that the light scattering of the photoanode film is increased and electron recombination is decreased when an appropriate amount of mesoporous TiO{sub 2} is used as a substrate for ZnO nanowires. The DSSC fabricated with the TiO{sub 2}/ZnO hybrid photoanode prepared with 15.8 wt. % TiO{sub 2} showed the highest conversion efficiency of 7.30%, approximately 5%, 18%, and 40% higher than that of DSSCs fabricated with 3.99 wt. % TiO{sub 2}, pure TiO{sub 2}, and pure ZnO photoanodes, respectively.

  7. Hybrid lead halide perovskites for light energy conversion: Excited state properties and photovoltaic applications

    NASA Astrophysics Data System (ADS)

    Manser, Joseph S.

    travel 220 nm over the course of 2 ns after photoexcitation, with an extrapolated diffusion length greater than one micrometer over the full excited state lifetime. The solution-processability of metal halide perovskites necessarily raises questions as to the properties of the solvated precursors and their connection to the final solid-state perovskite phase. Through structural and steady-state and time-resolved absorption studies, the important link between the excited state properties of the precursor components, composed of solvated and solid-state halometallate complexes, and CH3NH3PbI3 is evinced. This connection provides insight into optical nonlinearities and electronic properties of the perovskite phase. Fundamental studies of CH 3NH3PbI3 ultimately serve as a foundation for application of this and other related materials in high-performance devices. In the final chapter, the operation of CH3NH3PbI 3 solar cells in a tandem architecture is presented. The quest for economic, large scale hydrogen production has motivated the search for new materials and device designs capable of splitting water using only energy from the sun. In light of this, we introduce an all solution-processed tandem water splitting assembly composed of a BiVO4 photoanode and a single-junction CH3NH3PbI3 hybrid perovskite solar cell. This unique configuration allows efficient solar photon management, with the metal oxide photoanode selectively harvesting high energy visible photons and the underlying perovskite solar cell capturing lower energy visible-near IR wavelengths in a single-pass excitation. Operating without external bias under standard terrestrial one sun illumination, the photoanode-photovoltaic architecture, in conjunction with an earthabundant cobalt phosphate catalyst, exhibits a solar-to-hydrogen conversion efficiency of 2.5% at neutral pH. The design of low-cost tandem water splitting assemblies employing single-junction hybrid perovskite materials establishes a potentially

  8. Conversion Coefficients for Proton Beams using Standing and Sitting Male Hybrid Computational Phantom Calculated in Idealized Irradiation Geometries.

    PubMed

    Alves, M C; Santos, W S; Lee, C; Bolch, W E; Hunt, J G; Júnior, A B Carvalho

    2016-09-24

    The aim of this study was the calculation of conversion coefficients for absorbed doses per fluence (DT/Φ) using the sitting and standing male hybrid phantom (UFH/NCI) exposure to monoenergetic protons with energy ranging from 2 MeV to 10 GeV. Sex-averaged effective dose per fluence (E/Φ) using the results of DT/Φ for the male and female hybrid phantom in standing and sitting postures were also calculated. Results of E/Φ of UFH/NCI standing phantom were also compared with tabulated effective dose conversion coefficients provided in ICRP publication 116. To develop an exposure scenario implementing the male UFH/NCI phantom in sitting and standing postures was used the radiation transport code MCNPX. Whole-body irradiations were performed using the recommended irradiation geometries by ICRP publication 116 antero-posterior (AP), postero-anterior (PA), right and left lateral, rotational (ROT) and isotropic (ISO). In most organs, the conversion coefficients DT/Φ were similar for both postures. However, relative differences were significant for organs located in the lower abdominal region, such as prostate, testes and urinary bladder, especially in the AP geometry. Results of effective dose conversion coefficients were 18% higher in the standing posture of the UFH/NCI phantom, especially below 100 MeV in AP and PA. In lateral geometry, the conversion coefficients values below 20 MeV were 16% higher in the sitting posture. In ROT geometry, the differences were below 10%, for almost all energies. In ISO geometry, the differences in E/Φ were negligible. The results of E/Φ of UFH/NCI phantom were in general below the results of the conversion coefficients provided in ICRP publication 116.

  9. The influence of patient size on dose conversion coefficients: a hybrid phantom study for adult cardiac catheterization

    NASA Astrophysics Data System (ADS)

    Johnson, Perry; Lee, Choonsik; Johnson, Kevin; Siragusa, Daniel; Bolch, Wesley E.

    2009-06-01

    In this study, the influence of patient size on organ and effective dose conversion coefficients (DCCs) was investigated for a representative interventional fluoroscopic procedure—cardiac catheterization. The study was performed using hybrid phantoms representing an underweight, average and overweight American adult male. Reference body sizes were determined using the NHANES III database and parameterized based on standing height and total body mass. Organ and effective dose conversion coefficients were calculated for anterior-posterior, posterior-anterior, left anterior oblique and right anterior oblique projections using the Monte Carlo code MCNPX 2.5.0 with the metric dose area product being used as the normalization factor. Results show body size to have a clear influence on DCCs which increased noticeably when body size decreased. It was also shown that if patient size is neglected when choosing a DCC, the organ and effective dose will be underestimated to an underweight patient and will be overestimated to an underweight patient, with errors as large as 113% for certain projections. Results were further compared with those published for a KTMAN-2 Korean patient-specific tomographic phantom. The published DCCs aligned best with the hybrid phantom which most closely matched in overall body size. These results highlighted the need for and the advantages of phantom-patient matching, and it is recommended that hybrid phantoms be used to create a more diverse library of patient-dependent anthropomorphic phantoms for medical dose reconstruction.

  10. Enhanced Optoelectronic Conversion Efficiency of CdSe/ZnS Quantum Dot/Graphene/Silver Nanowire Hybrid Thin Films.

    PubMed

    Liu, Bo-Tau; Wu, Kuan-Han; Lee, Rong-Ho

    2016-12-01

    In this study, we prepared the reduced graphene oxide (rGO)-CdSe/ZnS quantum dots (QDs) hybrid films on a three-layer scaffold that the QD layer was sandwiched between the two rGO layers. The photocurrent was induced by virtue of the facts that the rGO quenched the photoluminescence of QDs and transferred the excited energy. The quenching mechanism was attributed to the surface energy transfer, supported in our experimental results. We found that the optoelectronic conversion efficiency of the hybrid films can be significantly improved by incorporating the silver nanowires (AgNWs) into the QD layer. Upon increasing AgNW content, the photocurrent density increased from 22.1 to 80.3 μA cm(-2), reaching a near 3.6-fold enhancement compared to the pristine rGO-QD hybrid films. According to the analyses of photoluminescence spectra, shape effect, and electrochemical impedance spectra, the enhancement on the optoelectronic conversion efficiency arise mainly from the strong quenching ability of silver and the rapid electron transfer of AgNWs.

  11. Enhanced Optoelectronic Conversion Efficiency of CdSe/ZnS Quantum Dot/Graphene/Silver Nanowire Hybrid Thin Films

    NASA Astrophysics Data System (ADS)

    Liu, Bo-Tau; Wu, Kuan-Han; Lee, Rong-Ho

    2016-09-01

    In this study, we prepared the reduced graphene oxide (rGO)-CdSe/ZnS quantum dots (QDs) hybrid films on a three-layer scaffold that the QD layer was sandwiched between the two rGO layers. The photocurrent was induced by virtue of the facts that the rGO quenched the photoluminescence of QDs and transferred the excited energy. The quenching mechanism was attributed to the surface energy transfer, supported in our experimental results. We found that the optoelectronic conversion efficiency of the hybrid films can be significantly improved by incorporating the silver nanowires (AgNWs) into the QD layer. Upon increasing AgNW content, the photocurrent density increased from 22.1 to 80.3 μA cm-2, reaching a near 3.6-fold enhancement compared to the pristine rGO-QD hybrid films. According to the analyses of photoluminescence spectra, shape effect, and electrochemical impedance spectra, the enhancement on the optoelectronic conversion efficiency arise mainly from the strong quenching ability of silver and the rapid electron transfer of AgNWs.

  12. Particle simulations of mode conversion between slow mode and fast mode in lower hybrid range of frequencies

    NASA Astrophysics Data System (ADS)

    Jia, Guozhang; Xiang, Nong; Wang, Xueyi; Huang, Yueheng; Lin, Yu

    2016-01-01

    The propagation and mode conversion of lower hybrid waves in an inhomogeneous plasma are investigated by using the nonlinear δf algorithm in a two-dimensional particle-in-cell simulation code based on the gyrokinetic electron and fully kinetic ion (GeFi) scheme [Lin et al., Plasma Phys. Controlled Fusion 47, 657 (2005)]. The characteristics of the simulated waves, such as wavelength, frequency, phase, and group velocities, agree well with the linear theoretical analysis. It is shown that a significant reflection component emerges in the conversion process between the slow mode and the fast mode when the scale length of the density variation is comparable to the local wavelength. The dependences of the reflection coefficient on the scale length of the density variation are compared with the results based on the linear full wave model for cold plasmas. It is indicated that the mode conversion for the waves with a frequency of 2.45 GHz (ω ˜ 3ωLH, where ωLH represents the lower hybrid resonance) and within Tokamak relevant amplitudes can be well described in the linear scheme. As the frequency decreases, the modification due to the nonlinear term becomes important. For the low-frequency waves (ω ˜ 1.3ωLH), the generations of the high harmonic modes and sidebands through nonlinear mode-mode coupling provide new power channels and thus could reduce the reflection significantly.

  13. Particle simulations of mode conversion between slow mode and fast mode in lower hybrid range of frequencies

    SciTech Connect

    Jia, Guozhang; Xiang, Nong; Huang, Yueheng; Wang, Xueyi; Lin, Yu

    2016-01-15

    The propagation and mode conversion of lower hybrid waves in an inhomogeneous plasma are investigated by using the nonlinear δf algorithm in a two-dimensional particle-in-cell simulation code based on the gyrokinetic electron and fully kinetic ion (GeFi) scheme [Lin et al., Plasma Phys. Controlled Fusion 47, 657 (2005)]. The characteristics of the simulated waves, such as wavelength, frequency, phase, and group velocities, agree well with the linear theoretical analysis. It is shown that a significant reflection component emerges in the conversion process between the slow mode and the fast mode when the scale length of the density variation is comparable to the local wavelength. The dependences of the reflection coefficient on the scale length of the density variation are compared with the results based on the linear full wave model for cold plasmas. It is indicated that the mode conversion for the waves with a frequency of 2.45 GHz (ω ∼ 3ω{sub LH}, where ω{sub LH} represents the lower hybrid resonance) and within Tokamak relevant amplitudes can be well described in the linear scheme. As the frequency decreases, the modification due to the nonlinear term becomes important. For the low-frequency waves (ω ∼ 1.3ω{sub LH}), the generations of the high harmonic modes and sidebands through nonlinear mode-mode coupling provide new power channels and thus could reduce the reflection significantly.

  14. Diffusion-Induced Hydrophilic Conversion of Polydimethylsiloxane/Block-Type Phospholipid Polymer Hybrid Substrate for Temporal Cell-Adhesive Surface.

    PubMed

    Seo, Ji-Hun; Ishihara, Kazuhiko

    2016-08-24

    In this study, diffusion-induced hydrophobic-hydrophilic conversion of the surface of the cross-linked polydimethylsiloxane (PDMS) substrate was realized by employing a simple swelling-deswelling process of PDMS substrate in a block-type polymer solution with the aim of development of a temporal cell-adhesive substrate. The ABA block-type polymer composed of poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) segment and PDMS segment with over 70% of dimethylsiloxane unit composition could be successfully incorporated in the PDMS substrate during the swelling-deswelling process to prepare the PDMS/phospholipid block copolymer hybrid substrates. During the aging process of the PDMS substrate for 4 days in aqueous medium, its surface property changed gradually from hydrophobic to hydrophilic. X-ray photoelectron spectroscopy and atomic force microscopy data provided strong evidence that the time-dependent hydrophilic conversion of the PDMS/block-type phospholipid polymer hybrid substrate was induced by the diffusion of the hydrophilic PMPC segment in the block-type polymer to be tethered on the substrate. During the hydrophilic conversion process, surface-adsorbed fibronectin was gradually desorbed from the substrate surface, and this resulted in successful detachment of two-dimensional connected cell crowds.

  15. A soft-template-conversion route to fabricate nanopatterned hybrid pt/carbon for potential use in counter electrodes of dye-sensitized solar cells.

    PubMed

    Jang, Yu Jin; Jang, Yoon Hee; Quan, Li Na; Kim, Ho-Cheol; Pyo, Seungmoon; Kim, Dong Ha

    2013-09-01

    Hybrid Pt(platinum)/carbon nanopatterns with an extremely low loading level of Pt catalysts derived from block copolymer templates as an alternative type of counter electrodes (CEs) in dye-sensitized solar cells (DSSCs) are proposed. DSSCs employing hybrid Pt/carbon with tailored configuration as CEs exhibit higher short-circuit current and conversion efficiencies as well as stability with a lapse of time compared with conventional cells on the basis of sputtered Pt thin films, evidencing that the new class of hybrid nanostructures possess high potential for cost-effective electrodes in energy conversion devices.

  16. Light-Trapping Characteristics of Ag Nanoparticles for Enhancing the Energy Conversion Efficiency of Hybrid Solar Cells.

    PubMed

    Fan, Zhiqiang; Zhang, Weijia; Ma, Qiang; Yan, Lanqin; Xu, Lihua; Fu, Yaolong

    2017-10-04

    In this paper, we investigated the optical and electrical characteristics of hybrid solar cells using silicon pyramid/Ag nanoparticle and nanowire/Ag nanoparticle nanocomposite structures, which are obtained by the Ag-assisted electroless etching method. We introduced the application of the physical and chemical properties of Ag nanoparticles on four kinds of solar cells: silicon pyramid, silicon pyramid/PEDOT:PSS, silicon nanowire, and silicon nanowire/PEDOT:PSS. We simulated the absorption of these structures for different parameters. Furthermore, we also show the result of the current density-voltage (J-V) characterization of the sample with Ag nanoparticles, which exhibits an improvement of the power conversion efficiency (PCE) in contrast to the samples without Ag nanoparticles. It was found that the properties of light-trapping of Ag nanoparticles have a prominent impact on improving the PCE of hybrid solar cells.

  17. Selective CO2 conversion to formate conjugated with H2O oxidation utilizing semiconductor/complex hybrid photocatalysts.

    PubMed

    Sato, Shunsuke; Arai, Takeo; Morikawa, Takeshi; Uemura, Keiko; Suzuki, Tomiko M; Tanaka, Hiromitsu; Kajino, Tsutomu

    2011-10-05

    Photoelectrochemical reduction of CO(2) to HCOO(-) (formate) over p-type InP/Ru complex polymer hybrid photocatalyst was highly enhanced by introducing an anchoring complex into the polymer. By functionally combining the hybrid photocatalyst with TiO(2) for water oxidation, selective photoreduction of CO(2) to HCOO(-) was achieved in aqueous media, in which H(2)O was used as both an electron donor and a proton source. The so-called Z-scheme (or two-step photoexcitation) system operated with no external electrical bias. The selectivity for HCOO(-) production was >70%, and the conversion efficiency of solar energy to chemical energy was 0.03-0.04%.

  18. Efficient conversion of furfuryl alcohol into alkyl levulinates catalyzed by an organic-inorganic hybrid solid acid catalyst.

    PubMed

    Zhang, Zehui; Dong, Kun; Zhao, Zongbao Kent

    2011-01-17

    A clean, facile, and environment-friendly catalytic method has been developed for the conversion of furfuryl alcohol into alkyl levulinates making use of the novel solid catalyst methylimidazolebutylsulfate phosphotungstate ([MIMBS]₃PW₁₂O₄₀). The solid catalyst is an organic-inorganic hybrid material, which consists of an organic cation and an inorganic anion. A study for optimizing the reaction conditions such as the reaction time, the temperature and the catalyst loading has been performed. Under optimal conditions, a high n-butyl levulinate yield of up to 93 % is obtained. Furthermore, the kinetics of the reaction pathways and the mechanism for the alcoholysis of furfuryl alcohol are discussed. This method is environmentally benign and economical for the conversion of biomass-based derivatives into fine chemicals.

  19. Electromagnetic particle simulation of the effect of toroidicity on linear mode conversion and absorption of lower hybrid waves

    NASA Astrophysics Data System (ADS)

    Bao, J.; Lin, Z.; Kuley, A.; Wang, Z. X.

    2016-06-01

    Effects of toroidicity on linear mode conversion and absorption of lower hybrid (LH) waves in fusion plasmas have been studied using electromagnetic particle simulation. The simulation confirms that the toroidicity induces an upshift of parallel refractive index when LH waves propagate from the tokamak edge toward the core, which affects the radial position for the mode conversion between slow and fast LH waves. Furthermore, moving LH antenna launch position from low field side toward high field side leads to a larger upshift of the parallel refractive index, which helps the slow LH wave penetration into the tokamak core. The broadening of the poloidal spectrum of the wave-packet due to wave diffraction is also verified in the simulation. Both the upshift and broadening effects of the parallel spectrum of the wave-packet modify the parallel phase velocity and thus the linear absorption of LH waves by electron Landau resonance.

  20. 2D materials. Graphene, related two-dimensional crystals, and hybrid systems for energy conversion and storage.

    PubMed

    Bonaccorso, Francesco; Colombo, Luigi; Yu, Guihua; Stoller, Meryl; Tozzini, Valentina; Ferrari, Andrea C; Ruoff, Rodney S; Pellegrini, Vittorio

    2015-01-02

    Graphene and related two-dimensional crystals and hybrid systems showcase several key properties that can address emerging energy needs, in particular for the ever growing market of portable and wearable energy conversion and storage devices. Graphene's flexibility, large surface area, and chemical stability, combined with its excellent electrical and thermal conductivity, make it promising as a catalyst in fuel and dye-sensitized solar cells. Chemically functionalized graphene can also improve storage and diffusion of ionic species and electric charge in batteries and supercapacitors. Two-dimensional crystals provide optoelectronic and photocatalytic properties complementing those of graphene, enabling the realization of ultrathin-film photovoltaic devices or systems for hydrogen production. Here, we review the use of graphene and related materials for energy conversion and storage, outlining the roadmap for future applications.

  1. Optoelectronic Components and Integrated Circuits Including Up and Down Conversion Technique and Hybrid Integration Technology

    DTIC Science & Technology

    2003-04-01

    solutions are also possible with (commercially available) DFB laser integrated with an electroabsorption modulator. 1-14 Another monolithic possible solution...discuss the monolithic integration of optoelectronic or photonic devices, recalling that the industrial way is based on hybrid technology on silicon...the integration (hybrid versus monolithic ) of components and circuits. 2. Emitters There is a lot of techniques to generate a microwave or millimetre

  2. Conversion of cellulose and cellobiose into sorbitol catalyzed by ruthenium supported on a polyoxometalate/metal-organic framework hybrid.

    PubMed

    Chen, Jinzhu; Wang, Shengpei; Huang, Jing; Chen, Limin; Ma, Longlong; Huang, Xing

    2013-08-01

    Cellulose and cellobiose were selectively converted into sorbitol over water-tolerant phosphotungstic acid (PTA)/metal- organic-framework-hybrid-supported ruthenium catalysts, Ru-PTA/MIL-100(Cr), under aqueous hydrogenation conditions. The goal was to investigate the relationship between the acid/metal balance of bifunctional catalysts Ru-PTA/MIL-100(Cr) and their performance in the catalytic conversion of cellulose and cellobiose into sugar alcohols. The control of the amount and strength of acid sites in the supported PTA/MIL-100(Cr) was achieved through the effective control of encapsulated-PTA loading in MIL-100(Cr). This design and preparation method led to an appropriately balanced Ru-PTA/MIL-100(Cr) in terms of Ru dispersion and hydrogenation capacity on the one hand, and acid site density of PTA/MIL-100(Cr) (responsible for acid-catalyzed hydrolysis) on the other hand. The ratio of acid site density to the number of Ru surface atoms (nA /nRu ) of Ru-PTA/MIL-100(Cr) was used to monitor the balance between hydrogenation and hydrolysis functions; the optimum balance between the two catalytic functions, that is, 8.84conversion of cellulose and cellobiose into hexitols. Under the applied reaction conditions, optimal results (63.2% yield in hexitols with a selectivity for sorbitol of 57.9% at complete conversion of cellulose, and 97.1% yield in hexitols with a selectivity for sorbitol of 95.1% at complete conversion of cellobiose) were obtained using a Ru-PTA/MIL-100(Cr) catalyst with loadings of 3.2 wt % for Ru and 16.7 wt % for PTA. This research thus opens new perspectives for the rational design of acid/metal bifunctional catalysts for biomass conversion.

  3. Hybrid micro-scale photovoltaics for enhanced energy conversion across all irradiation conditions

    NASA Astrophysics Data System (ADS)

    Agrawal, Gautam

    A novel hybrid photovoltaics (HPV) architecture is presented that integrates high-performance micro-optics-based concentrator photovoltaics (CPV) array technology with a 1-sun photovoltaic (PV) cell within a low-profile panel structure. The approach simultaneously captures the direct solar radiation components with arrayed high-efficiency CPV cells and the diffuse solar components with an underlying wide-area PV cell. Performance analyses predict that the hybrid approach will significantly enhance the average energy produced per unit area for the full range of diffuse/direct radiation patterns across the USA. Furthermore, cost analyses indicate that the hybrid concept may be financially attractive for a wide range of locations. Indoor and outdoor experimental evaluation of a micro-optical system designed for use in a hybrid architecture verified that a large proportion of the direct radiation component was concentrated onto emulated micro-cell regions while most of the diffuse radiation and the remaining direct radiation was collected in the 1-sun cell area.

  4. Relationship between the degree of conversion, solubility and salivary sorption of a hybrid and a nanofilled resin composite.

    PubMed

    da Silva, Eduardo Moreira; Almeida, Giselle Soares; Poskus, Laiza Tatiana; Guimarães, José Guilherme Antunes

    2008-01-01

    This study analyzed the relationship between the degree of conversion (DC), solubility, and salivary sorption of a hybrid (Filtek P 60) and a nanofilled resin composite (Filtek Supreme), and evaluated the influence of the light-activation mode on these properties. Two light-activation modes were used: Conventional (C; 850 mW/cm(2) for 20 s) and Soft-start (SS; 100-1,000 mW/cm(2) for 10 s + 1,000 mW/cm(2) for 10 s). The DC (%) was evaluated by FT-Raman spectroscopy. The solubility and salivary sorption were measured after immersion in artificial saliva for 7 days. Data were analyzed by ANOVA and Student-Newman-Keuls' test and linear regression analysis (a = 0.05). The DC varied from 50.52% (nanofilled composite) to 57.15% (hybrid composite), and was influenced by the light-activation mode: C > SS. The solubility (0.45 microg/mm(3)) and salivary sorption (8.04 microg/mm(3)) of the nanofilled composite were greater than those of the hybrid composite (0.40 microg/mm(3) / 6.87 microg/mm(3)), and were influenced by the light-activation mode: SS > C. Correlation was found between DC and solubility (r = - 0.89, p<0.05), as well as between solubility and salivary sorption (r = 0.95). These findings suggest that nanofilled composites may present higher degradation in the oral environment than hybrid ones. Soft-start light-activation mode may increase the solubility of resin composites.

  5. A study of the thermoregulatory characteristics of a liquid-cooled garment with automatic temperature control based on sweat rate: Experimental investigation and biothermal man-model development

    NASA Technical Reports Server (NTRS)

    Chambers, A. B.; Blackaby, J. R.; Miles, J. B.

    1973-01-01

    Experimental results for three subjects walking on a treadmill at exercise rates of up to 590 watts showed that thermal comfort could be maintained in a liquid cooled garment by using an automatic temperature controller based on sweat rate. The addition of head- and neck-cooling to an Apollo type liquid cooled garment increased its effectiveness and resulted in greater subjective comfort. The biothermal model of man developed in the second portion of the study utilized heat rates and exchange coefficients based on the experimental data, and included the cooling provisions of a liquid-cooled garment with automatic temperature control based on sweat rate. Simulation results were good approximations of the experimental results.

  6. One-step preparation of multiwall carbon nanotube/silicon hybrids for solar energy conversion

    NASA Astrophysics Data System (ADS)

    Lobiak, Egor V.; Bychanok, Dzmitry S.; Shlyakhova, Elena V.; Kuzhir, Polina P.; Maksimenko, Sergey A.; Bulusheva, Lyubov G.; Okotrub, Alexander V.

    2016-03-01

    The hybrid material consisting of a thin layer of multiwall carbon nanotubes (MWCNTs) on an n-doped silicon wafer was obtained in one step using an aerosol-assisted catalytic chemical vapor deposition. The MWCNTs were grown from a mixture of acetone and ethanol with ˜0.2 wt.% of iron polyoxomolybdate nanocluster of the keplerate-type structure. The samples produced at 800°C and 1050°C were tested as a solar energy converter. It was shown that photoresponse of the hybrid material significantly depends on the presence of structural defects in MWCNTs, being much higher in the case of more defective nanotubes. This is because defects lead to p-doping of nanotubes, whereas the p-n heterojunction between MWCNTs and silicon provides a high efficiency of the solar cell.

  7. Lower hybrid heating associated with mode conversion on the Wisconsin toroidal octupole

    SciTech Connect

    Owens, T L; Scharer, J E

    1980-09-01

    Wave heating experiments and wave propagation measurements in the lower hybrid range of frequencies are described. A T antenna launches up to 40 kW of wave power at 140 MHz with better than 95% coupling efficiency. Ion temperature increases of ..delta..T/sub i/ = 37 eV are measured with ..delta..T/sub parallel//T/sub io/ = 12. Ion heating is strongly localized near the lower hybrid turning point for a peak value of (k/sub parallel//..omega..)(KT/sub i//m/sub e/)/sup 1/2/ approx. = 0.3 corresponding to an upshifted k/sub parallel/ spectrum. Wavelength measurements indicate that the upshift in k/sub parallel/ occurs in the interior of the plasma. Other wave measurements show the existence of a large amplitude weakly damped fast wave component in addition to the slow wave.

  8. Enhanced Harmonic Up-Conversion Using a Hybrid HGHG-EEHG Scheme

    SciTech Connect

    Marksteiner, Quinn R.; Bishofberger, Kip A.; Carlsten, Bruce E.; Freund, Henry P.; Yampolsky, Nikolai A.

    2012-04-30

    We introduce a novel harmonic generation scheme which can be used, for a given desired harmonic, to achieve higher bunching factors, weaker chicanes, and/or less final energy spread than can be achieved using Echo-Enabled Harmonic Generation. This scheme only requires a single laser with relatively low power, and is a hybrid of High-Gain Harmonic Generation and EEHG. We present a design of this scheme applied to the Next Generation Light Source (NGLS).

  9. Conversion of Isoprenoid Oil by Catalytic Cracking and Hydrocracking over Nanoporous Hybrid Catalysts

    PubMed Central

    Kimura, Toshiyuki; Liu, Chen; Li, Xiaohong; Maekawa, Takaaki; Asaoka, Sachio

    2012-01-01

    In order to produce petroleum alternatives from biomass, a significant amount of research has been focused on oils from microalgae due to their origin, which would not affect food availability. Nanoporous hybrid catalysts composed of ns Al2O3 and zeolites have been proven to be very useful compared to traditional catalysts in hydrotreating (HT), hydrocracking (HC), and catalytic cracking (CC) of large molecules. To evaluate the reaction scheme and products from model isoprenoid compounds of microalgae oil, nanoporous hybrid catalyst technologies (CC: ns Al2O3/H-USY and ns Al2O3/H-GaAlMFI; HC: [Ni-Mo/γ-Al2O3]/ns Al2O3/H-beta) were studied. The major product from CC on ns Al2O3/H-USY was highly aromatic gasoline, while the product from HC was half-isoparaffinic/olefinic kerosene. Although more than 50 wt% of the products from HT/CC on the USY catalyst was liquefied petroleum gas due to overcracking, the product from HT/CC on the MFI catalyst was high-octane-number gasoline. Delightfully, the product from HT/HC was kerosene and its average number was 11, with more than 80 wt% being isoparaffinic. As a result, it was demonstrated that hydrotreating may convert isoprenoid oil from microalgae over nanoporous hybrid catalysts into a variety of products. PMID:22791962

  10. Lignocellulose-degrading enzymes, free-radical transformations during composting of lignocellulosic waste and biothermal phases in small-scale reactors.

    PubMed

    Bohacz, Justyna

    2017-02-15

    Environmentally friendly strategies of waste management are both part of legal solutions currently in place and a focus of interest worldwide. Large-scale composting plants are set up across various regions while home composting is becoming increasingly popular. A variety of microbial groups are successively at work during composting and enzymatic activities detected in the composting mass fluctuate accordingly. Changes in the activities of oxidoreductases and hydrolases, i.e. glucose oxidase, horseradish peroxidase, lignin peroxidase, laccase, xylanase, superoxide dismutase and keratinase, low-molecular weight compounds, i.e. methoxyphenolic and hydroxyphenolic compounds, and the relative level of superoxide radicals and glucose were determined periodically in water extracts of composts to investigate the process of biochemical transformations of ligninocellulose in relation to biothermal phases and to identify a potential priming effect in two composts containing different ratios of lignocellulosic waste and chicken feathers. Composting was conducted for 30weeks. An important aim of the study was to demonstrate that a positive priming effect was induced during composting of a variety of lignocellulosic waste types using native keratin (chicken feathers) as a source of N. The effect was more evident in compost containing grass, which was related to a more rapid depletion of easily available sources of C and energy (glucose) during composting. Ligninolytic enzymes known to biodegrade recalcitrant organic matter were induced in subsequent biothermal phases of composting. Compost I enriched with grass (pine bark, grass, sawdust and chicken feathers) exhibited a higher enzymatic activity than compost II which did not contain any grass but which had a greater number of hardly-degradable components (pine bark, wheat straw, sawdust, chicken feathers). Similar observations were made for the concentrations of low-molecular weight compounds. The enzymes activities and

  11. Effect of LED and Argon Laser on Degree of Conversion and Temperature Rise of Hybrid and Low Shrinkage Composite Resins

    PubMed Central

    Pahlevan, Ayob; Tabatabaei, Masumeh Hasani; Arami, Sakineh; Valizadeh, Sara

    2016-01-01

    Objectives: Different light curing units are used for polymerization of composite resins. The aim of this study was to evaluate the degree of conversion (DC) and temperature rise in hybrid and low shrinkage composite resins cured by LED and Argon Laser curing lights. Materials and Methods: DC was measured using FTIR spectroscopy. For measuring temperature rise, composite resin samples were placed in Teflon molds and cured from the top. The thermocouple under samples recorded the temperature rise. After initial radiation and specimens reaching the ambient temperature, reirradiation was done and temperature was recorded again. Both temperature rise and DC data submitted to one-way ANOVA and Tukey-HSD tests (5% significance). Results: The obtained results revealed that DC was not significantly different between the understudy composite resins or curing units. Low shrinkage composite resin showed a significantly higher temperature rise than hybrid composite resin. Argon laser caused the lowest temperature rise among the curing units. Conclusion: Energy density of light curing units was correlated with the DC. Type of composite resin and light curing unit had a significant effect on temperature rise due to polymerization and curing unit, respectively. PMID:27843507

  12. Synthesis of hybrid organic-inorganic nanocomposite materials based on CdS nanocrystals for energy conversion applications

    NASA Astrophysics Data System (ADS)

    Laera, A. M.; Resta, V.; Ferrara, M. C.; Schioppa, M.; Piscopiello, E.; Tapfer, L.

    2011-11-01

    Efficient solar energy conversion is strongly related to the development of new materials with enhanced functional properties. In this context, a wide variety of inorganic, organic, or hybrid nanostructured materials have been investigated. In particular, in hybrid organic-inorganic nanocomposites are combined the convenient properties of organic polymers, such as easy manipulation and mechanical flexibility, and the unique size-dependent properties of nanocrystals (NCs). However, applications of hybrid nanocomposites in photovoltaic devices require a homogeneous and highly dense dispersion of NCs in polymer in order to guarantee not only an efficient charge separation, but also an efficient transport of the carriers to the electrodes without recombination. In previous works, we demonstrated that cadmium thiolate complexes are suitable precursors for the in situ synthesis of nanocrystalline CdS. Here, we show that the soluble [Cd(SBz)2]2·(1-methyl imidazole) complex can be efficiently annealed in a conjugated polymer obtaining a nanocomposite with a regular and compact network of NCs. The proposed synthetic strategies require annealing temperatures well below 200 °C and short time for the thermal treatment, i.e., less than 30 min. We also show that the same complex can be used to synthesize CdS NCs in mesoporous TiO2. The adsorption of cadmium thiolate molecule in TiO2 matrix can be obtained by using chemical bath deposition technique and subsequent thermal annealing. The use of NCs, quantum dots, as sensitizers of TiO2 matrices represents a very promising alternative to common dye-sensitized solar cells and an interesting solution for heterogeneous photocatalysis.

  13. Novel Integration of Perovskite Solar Cell and Supercapacitor Based on Carbon Electrode for Hybridizing Energy Conversion and Storage.

    PubMed

    Liu, Zhiyong; Zhong, Yan; Sun, Bo; Liu, Xingyue; Han, Jinghui; Shi, Tielin; Tang, Zirong; Liao, Guanglan

    2017-07-12

    Power packs integrating both photovoltaic parts and energy storage parts have gained great scientific and technological attention due to the increasing demand for green energy and the tendency for miniaturization and multifunctionalization in electronics industry. In this study, we demonstrate novel integration of perovskite solar cell and solid-state supercapacitor for power packs. The perovskite solar cell is integrated with the supercapacitor based on common carbon electrodes to hybridize photoelectric conversion and energy storage. The power pack achieves a voltage of 0.84 V when the supercapacitor is charged by the perovskite solar cell under the AM 1.5G white light illumination with a 0.071 cm(2) active area, reaching an energy storage proportion of 76% and an overall conversion efficiency of 5.26%. When the supercapacitor is precharged at 1.0 V, an instant overall output efficiency of 22.9% can be achieved if the perovskite solar cell and supercapacitor are connected in series, exhibiting great potential in the applications of solar energy storage and flexible electronics such as portable and wearable devices.

  14. Electromagnetic particle simulation of the effect of toroidicity on linear mode conversion and absorption of lower hybrid waves

    NASA Astrophysics Data System (ADS)

    Bao, Jian; Lin, Zhihong; Kuley, Animesh; Wang, Zhixuan

    2016-10-01

    Effects of toroidicity on linear mode conversion and absorption of lower hybrid (LH) waves in tokamak have been studied by electromagnetic particle simulation using GTC. The simulation confirms that the toroidicity induces an upshift of parallel refractive index when LH waves propagate from the tokamak edge toward the core, which affects the radial position for the mode conversion between slow and fast LH waves. Furthermore, moving LH antenna launch position from low field side toward high field side leads to a larger upshift of the parallel refractive index, which helps the slow LH wave penetration into the tokamak core. The broadening of the poloidal spectrum of the wave-packet due to wave diffraction is also verified in the simulation. Both the upshift and broadening effects of the parallel spectrum of the wave-packet modify the parallel phase velocity and thus the linear absorption of LH waves by electron Landau resonance. In the nonlinear electromagnetic simulation, nonlinear wave trapping of electrons is verified and a plasma current is nonlinearly driven. Preliminary results of the nonlinear parametric decay of LH waves will be presented.

  15. Improvement of color conversion and efficiency droop in hybrid light-emitting diodes utilizing an efficient non-radiative resonant energy transfer

    NASA Astrophysics Data System (ADS)

    Zhuang, Zhe; Dai, Jiangping; Liu, Bin; Guo, Xu; Li, Yi; Tao, Tao; Zhi, Ting; Zhang, Guogang; Xie, Zili; Ge, Haixiong; Shi, Yi; Zheng, Youdou; Zhang, Rong

    2016-10-01

    Blue InGaN/GaN nanohole light-emitting diodes have been fabricated by soft UV-curing nanoimprint lithography, filling with CdSe/ZnS core/shell nanocrystals (NCs) as color conversion mediums. The excitonic recombination dynamics of hybrid nanohole light-emitting diodes were investigated by time-resolved photoluminescence, observing a significant reduction in the decay lifetime of excitons as a result of an efficient non-radiative resonant energy transfer, which leads to the improvement of color conversion and efficiency droop in these hybrid nanohole light-emitting diodes compared to hybrid nanocrystals/standard planar light-emitting diodes. The color-conversion efficiency and effective quantum yield of hybrid nanohole light-emitting diodes were nearly twice as much as those of hybrid standard light-emitting diodes. A model on the excitonic recombination process was proposed to explore this situation, explaining the advantages of non-radiative resonant energy transfer that avoiding energy loss associated with the intermediate light emission and conversion steps and transferring energy non-radiatively and resonantly to NCs with a higher quantum yield. The efficiency droop of hybrid nanohole light-emitting diodes was validly suppressed compared to the bare ones, even better than that of hybrid standard light-emitting diodes. It mainly results from the extraction of excess carrier concentrations in InGaN/GaN multiple quantum wells via the rapid non-radiative resonant energy transfer process under the higher injection condition, revealing a great potential to realize efficient white light emitters in the future.

  16. Impact of Dissolved Oxygen on Feed Conversion, Feed Consumption, and Growth of Blue Catfish Ictalurus furcatus, Channel Catfish I. punctatus, and Blue X Channel Catfish Hybrids

    USDA-ARS?s Scientific Manuscript database

    Studies were conducted in 15 1-acre and six ¼-acre ponds over several years to determine the effect of low dissolved oxygen (DO) concentration on food conversion ratio (FCR), food consumption, growth, and net production of blue catfish (BC), channel catfish (CC), and their hybrid (BC X CC). Control ...

  17. Advanced Power Conversion Efficiency in Inventive Plasma for Hybrid Toroidal Reactor

    NASA Astrophysics Data System (ADS)

    Hançerlioğullari, Aybaba; Cini, Mesut; Güdal, Murat

    2013-08-01

    Apex hybrid reactor has a good potential to utilize uranium and thorium fuels in the future. This toroidal reactor is a type of system that facilitates the occurrence of the nuclear fusion and fission events together. The most important feature of hybrid reactor is that the first wall surrounding the plasma is liquid. The advantages of utilizing a liquid wall are high power density capacity good power transformation productivity, the magnitude of the reactor's operational duration, low failure percentage, short maintenance time and the inclusion of the system's simple technology and material. The analysis has been made using the MCNP Monte Carlo code and ENDF/B-V-VI nuclear data. Around the fusion chamber, molten salts Flibe (LI2BeF4), lead-lithium (PbLi), Li-Sn, thin-lityum (Li20Sn80) have used as cooling materials. APEX reactor has modeled in the torus form by adding nuclear materials of low significance in the specified percentages between 0 and 12 % to the molten salts. In this study, the neutronic performance of the APEX fusion reactor using various molten salts has been investigated. The nuclear parameters of Apex reactor has been searched for Flibe (LI2BeF4) and Li-Sn, for blanket layers. In case of usage of the Flibe (LI2BeF4), PbLi, and thin-lityum (Li20Sn80) salt solutions at APEX toroidal reactors, fissile material production per source neutron, tritium production speed, total fission rate, energy reproduction factor has been calculated, the results obtained for both salt solutions are compared.

  18. Toyota Prius Hybrid Plug-in Conversation and Battery Monitoring system

    NASA Astrophysics Data System (ADS)

    Unnikannan, Krishnanunni; McIntyre, Michael; Harper, Doug; Kessinger, Robert; Young, Megan; Lantham, Joseph

    2012-03-01

    The objective of the project was to analyze the performance of a Toyota Hybrid. We started off with a stock Toyota Prius and taking data by driving it in city and on the highway in a mixed pre-determined route. The batteries can be charged using standard 120V AC outlets. First phase of the project was to increase the performance of the car by installing 20 Lead (Pb) batteries in a plug-in kit. To improve the performance of the kit, a centralized battery monitoring system was installed. The battery monitoring system has two components, a custom data modules and a National Instruments CompactRIO. Each Pb battery has its own data module and all the data module are connected to the CompactRIO. The CompactRIO records differential voltage, current and temperature from all the 20 batteries. The LabVIEW software is dynamic and can be reconfigured to any number of batteries and real time data from the batteries can be monitored on a LabVIEW enabled machine.

  19. Toyota Prius Hybrid Plug-in Conversation and Battery Monitoring system

    NASA Astrophysics Data System (ADS)

    McIntyre, Michael; Kessinger, Robert; Young, Maegan; Latham, Joseph; Unnikannan, Krishnanunni

    2012-02-01

    The objective of the project was to analyze the performance of a Toyota Hybrid. We started off with a stock Toyota Prius and taking data by driving it in city and on the highway in a mixed pre-determined route. The batteries can be charged using standard 120V AC outlets. First phase of the project was to increase the performance of the car by installing 20 Lead (Pb) batteries in a plug-in kit. To improve the performance of the kit, a centralized battery monitoring system was installed. The battery monitoring system has two components, a custom data modules and a National Instruments CompactRIO. Each Pb battery has its own data module and all the data module are connected to the CompactRIO. The CompactRIO records differential voltage, current and temperature from all the 20 batteries. The LabVIEW software is dynamic and can be reconfigured to any number of batteries and real time data from the batteries can be monitored on a LabVIEW enabled machine.

  20. Living hybrid materials capable of energy conversion and CO2 assimilation.

    PubMed

    Meunier, Christophe F; Rooke, Joanna C; Léonard, Alexandre; Xie, Hao; Su, Bao-Lian

    2010-06-14

    This paper reviews our work on the fabrication of photobiochemical hybrid materials via immobilisation of photosynthetically active entities within silica materials, summarising the viability and productivity of these active entities post encapsulation and evaluating their efficiency as the principal component of a photobioreactor. Immobilisation of thylakoids extracted from spinach leaves as well as whole cells such as A. thaliana, Synechococcus and C. caldarium was carried out in situ using sol-gel methods. In particular, a comprehensive overview is given of the efforts to find the most biocompatible inorganic precursors that can extend the lifetime of the organisms upon encapsulation. The effect of matrix-cell interactions on cell lifetime and the photosynthetic efficiency of the resultant materials are discussed. Precursors based on alkoxides, commonly used in "Chimie Douce" to form porous silica gel, release by-products which are often cytotoxic. However by controlling the formation of gels from aqueous silica precursors and silica nanoparticles acting as "cements" one can significantly enhance the life span of the entrapped organelles and cells. Adapted characteristic techniques have shown survival times of up to 5 months with the photosynthetic production of oxygen recorded as much as 17 weeks post immobilisation. These results constitute a significant advance towards the final goal, long-lasting semi-artificial photobioreactors that can advantageously exploit solar radiation to convert polluting carbon dioxide into useful biofuels, sugars or medical metabolites.

  1. Nanostructured hybrid materials based on reduced graphene oxide for solar energy conversion

    NASA Astrophysics Data System (ADS)

    Morais, Andreia; Amaral Carminati, Saulo do; Nogueira, Ana Flavia

    2016-09-01

    Research on carbon-based photocatalytic nanomaterials has been a field in continuous expansion in the last years. Graphene (or its derivatives) is currently one of the most studied materials due to its high surface area, photodegradation resistance, optical transparency and high charge mobility values. All of these excellent properties are highlighted for applications in various research areas. The incorporation of small amounts of reduced graphene oxide (RGO) sheets in semiconductors matrices is also a strategy widely used to improve the physicochemical properties, which cannot normally be achieved using conventional composites or pristine semiconductors. Most studies suggest that these twodimensional (2D) materials can facilitate electron injection and assist the electron transport in semiconductors. In this context, this manuscript will present examples of graphene-based semiconductor nanocomposites obtained by our research group and their application in the photodegradation of methylene blue (MB), photocatalytic conversion of CO2 to hydrocarbon fuels and photocatalytic water splitting reaction. Our results show the positive effect of coupling the RGO sheets with semiconductors for photocatalysis.

  2. Exact Order Reduction Method for Mode Conversion for Harmonics or Two-Ion Hybrid Resonances

    NASA Astrophysics Data System (ADS)

    Johnston, S.; Swanson, D. G.

    1996-11-01

    The Exact Order Reduction method(D.G. Swanson, et al., AIP Conference Proceedings 159, 342(1987).) solves the full fourth-order system of equations by taking the numerical solutions of a pair of second-order equations for the fast wave and slow wave, respectively, which are easily obtained, and then uses an associated integral equation to obtain the coupling between the fast and slow waves. In the original method, the integral equations had singularities near the axis which compromised the accuracy and convergence, but by altering the integration path, the numerical problems are resolved. This allows accurate estimates for mode conversion efficiencies in realistic geometries as the integral equation is solved only in a narrow region near resonance, taking the global fast wave solution of the reduced second order equation over the cross section for two of the four basis functions, and the slow wave solutions over the strip for the other basis functions. The method makes virtually no approximations except that it is first order in Larmor radius.

  3. Hybrid depth cueing for 2D-to-3D conversion system

    NASA Astrophysics Data System (ADS)

    Cheng, Chao-Chung; Li, Chung-Te; Tsai, Yi-Min; Chen, Liang-Gee

    2009-02-01

    The three-dimensional (3D) displays provide a dramatic improvement of visual quality than the 2D displays do. The conversion of existing 2D videos to 3D videos is necessary for multimedia application. This paper presents a robust system to convert 2D videos to 3D videos. The main concepts are to extract the depth information from motion parallax of moving picture and to depth information from geometrical perspective in non-moving scene. In the first part, depthinduced motion information is reconstructed by motion vector to disparity mapping. By warping the consecutive video frames to parallel view angle with the current frame, the frame with suitable baseline is selected to generate depth using motion parallax information. However, video may not have the depth-induced motion information in every case. For scene without motion parallax, depth from geometrical perspective is applied to generate scene depth map. Scene depth map is assigned depending on the scene mode and analyzed line structure in the video. Combining these two depth cues, the stereo effect is enhanced and provide spectacular depth map. The depth map is then used to render the multi-view video for 3D display.

  4. Enhanced Conversion Efficiency for Si Nanowire-Organic Hybrid Solar Cells through the Incorporation of Organic Small Molecule

    NASA Astrophysics Data System (ADS)

    He, Lining; Jiang, Changyun; Lai, Donny; Wang, Hao; Rusli

    2012-10-01

    We demonstrate high-efficiency hybrid solar cells based on heterojunctions formed between n-type silicon nanowires (SiNWs) and p-type organic semiconductors fabricated using a simple solution-based approach. Two types of devices have been fabricated with different organic materials used, namely poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) and a small molecule, 2,2',7,7'-tetrakis(N,N-di-4-methoxyphenylamino)-9,9'-spirobifluorene (Spiro-OMeTAD). The cells are characterized and compared in terms of their physical characteristics and photovoltaic performance. Using SiNWs of the same length of 0.35 µm, it is found that the SiNWs/Spiro cells exhibit a power conversion efficiency of 10.3%, which is higher than the 7.7% of SiNWs/PEDOT cells. The results are interpreted in terms of the ability of the two organic semiconductors to fill the gaps between the SiNWs and the optical reflectance of the samples. The degradation of the SiNWs/Spiro cells is also studied and presented.

  5. CdSe quantum dot-fullerene hybrid nanocomposite for solar energy conversion: electron transfer and photoelectrochemistry.

    PubMed

    Bang, Jin Ho; Kamat, Prashant V

    2011-12-27

    The development of organic/inorganic hybrid nanocomposite systems that enable efficient solar energy conversion has been important for applications in solar cell research. Nanostructured carbon-based systems, in particular C(60), offer attractive strategies to collect and transport electrons generated in a light harvesting assembly. We have assembled CdSe-C(60) nanocomposites by chemically linking CdSe quantum dots (QDs) with thiol-functionalized C(60). The photoinduced charge separation and collection of electrons in CdSe QD-C(60) nanocomposites have been evaluated using transient absorption spectroscopy and photoelectrochemical measurements. The rate constant for electron transfer between excited CdSe QD and C(60) increased with the decreasing size of the CdSe QD (7.9 × 10(9) s(-1) (4.5 nm), 1.7 × 10(10) s(-1) (3.2 nm), and 9.0 × 10(10) s(-1) (2.6 nm)). Slower hole transfer and faster charge recombination and transport events were found to dominate over the forward electron injection process, thus limiting the deliverance of maximum power in CdSe QD-C(60)-based solar cells. The photoinduced charge separation between CdSe QDs and C(60) opens up new design strategies for developing light harvesting assemblies.

  6. Dispersion engineering of a As2Se3-based strip/slot hybrid waveguide for mid-infrared broadband wavelength conversion

    NASA Astrophysics Data System (ADS)

    Hui, Zhanqiang; Zhang, Lingxuan; Wang, Leiran; Zhang, Wenfu

    2016-10-01

    An arsenic tri-selenide-based strip/slot hybrid waveguide with a single horizontal silica slot is proposed to achieve an extremely low and flat dispersion with three zero dispersion wavelengths. By adjusting the geometrical structural parameters of the hybrid waveguide, dispersion tailoring is fully obtained. The flat group velocity dispersion varying between ±0.08 ps2/(m) is obtained over a 1253 nm bandwidth. The parameters of effective area, nonlinear coefficient, and third-order dispersion are all investigated. Moreover, a compact on-chip all-optical wavelength converter is designed based on degenerate four-wave mixing in this waveguide. The dependencies of conversion efficiency and conversion bandwidth on the pump wavelength are discussed. The impact of pump power and signal power on the conversion efficiency is also investigated. The results show that a maximal conversion efficiency of -0.46 dB, and a 3-dB conversion bandwidth of 830 nm in the mid-infrared is achieved.

  7. Hybrid gas-to-particle conversion and chemical vapor deposition for production of high-surface area films

    NASA Astrophysics Data System (ADS)

    Nguyen, Quynh Tan

    A hybrid process, based upon gas-to-particle conversion and chemical vapor deposition, is presented as an alternative technique for producing porous films with the main advantages of solvent-free, low-substrate temperature operation. Starting from solid precursors, nanoparticles were produced in the vapor phase. Downstream of this reaction zone, these nanoparticles were collected via thermophoresis onto a cooled substrate forming a porous film. Initially, alumina (Al2O3) films were produced. Later, multi-component processing was explored by incorporating platinum (Pt) nanoparticles into the Al2O3 matrix leading to the production of Pt/Al 2O3 films by two routes: simultaneous precursor injection processing or by a layer-by-layer approach. In single component processing, the formation of nanoparticle aggregates was evident within the amorphous Al2O3 films. Aggregates, composed of these particles, are likely held together by relatively weak van der Waals forces leading to the observed poor physical cohesion. In multi-component processing, reasonable control of composition and distribution of species is possible with Pt nanoparticles appearing to be co-agglomerated with alumina. Deposited crystalline Pt nanoparticles may encourage the crystallization of the amorphous Al2O3. Finally, from chemisorption results, the produced sample appears to have potentially greater catalytic activity than a commercially available standard. A model is in development to study nanoparticle interactions with a gas and deposition occurring in stagnation flow onto the cooled horizontal substrate within the tubular reactor. Using velocity and temperature fields generated from numerical solutions to the Navier-Stokes and energy equations, particle trajectories were calculated from the summation of drag, gravitational, thermophoretic, and Brownian forces. In rectangular coordinates, cooling stage width to reactor diameter ratio, deposition stage temperature, and initial velocity were the

  8. SnO2-based dye-sensitized hybrid solar cells exhibiting near unity absorbed photon-to-electron conversion efficiency.

    PubMed

    Snaith, Henry J; Ducati, Caterina

    2010-04-14

    Improving the solar light harvesting and photon-to-electron conversion efficiency for hybrid, organic-inorganic photovoltaics are critical challenges. Titania based solid-state hybrid solar cells are moderately efficient at converting visible photons to electrons, but major electrical losses still remain. A material based paradigm shift is required to dramatically enhance the performance of these devices. Here, we present an investigation into solid-state dye-sensitized solar cells (SDSCs) incorporating a molecular hole-transporter and mesoporous tin oxide electrodes, in place of titania usually employed. We investigate the influence of treating the surface of the SnO(2) with different oxides and find that MgO "passivated" SnO(2) electrodes demonstrate an unprecedented absorbed photon-to-electron conversion efficiency of near unity across a broad spectral range. A dual surface treatment of TiO(2) followed by MgO enables tuning of the solar cell photovoltage, fill factor, and efficiency with visible light absorbing cells delivering 3% solar-to-electrical full sun power conversion efficiency.

  9. Solid-State Conversion Chemistry of Multicomponent Nanocrystals Cast in a Hollow Silica Nanosphere: Morphology-Controlled Syntheses of Hybrid Nanocrystals.

    PubMed

    Kim, Yeon Jun; Choi, Jung Kyu; Lee, Dong-Gyu; Baek, Kyungjoon; Oh, Sang Ho; Lee, In Su

    2015-11-24

    During thermal transformation of multicomponent nanocrystals in a silica nanosphere, FeAuPd alloy nanocrystals migrate outward and thereby leave a cavity in the silica matrix. Oxidation then converts these nanocrystals back into phase-segregated hybrid nanocrystals, AuPd@Fe3O4, with various morphologies. The FeAuPd-to-AuPd@Fe3O4 transformation was cast by the in situ generated hollow silica mold. Therefore, the morphological parameters of the transformed AuPd@Fe3O4 are defined by the degree of migration of the FeAuPd in the hollow silica nanoshell. This hollow silica-cast nanocrystal conversion was studied to develop a solid state protocol that can be used to produce a range of hybrid nanocrystals and that allows for systematic and sophisticated control of the resulting morphologies.

  10. Synergistic Effects in Nanoengineered HNb3O8/Graphene Hybrids with Improved Photocatalytic Conversion Ability of CO2 into Renewable Fuels.

    PubMed

    Liu, He; Zhang, Haitao; Shen, Peng; Chen, Feixiong; Zhang, Suojiang

    2016-01-12

    Layered HNb3O8/graphene hybrids with numerous heterogeneous interfaces and hierarchical pores were fabricated via the reorganization of exfoliated HNb3O8 nanosheets with graphene nanosheets (GNs). Numerous interfaces and pores were created by the alternative stacking of HNb3O8 nanosheets with limited size and GNs with a buckling and folding feature. The photocatalytic conversation of CO2 into renewable fuels by optimized HNb3O8/G hybrids yields 8.0-fold improvements in CO evolution amounts than that of commercial P25 and 8.6-fold improvements than that of HNb3O8 bulk powders. The investigation on the relationships between microstructures and improved photocatalytic performance demonstrates that the improved photocatalytic performance is attributed to the exotic synergistic effects via the combination of enhanced specific BET surface area, increased strong acid sites and strong acid amounts, narrowed band gap energy, depressed electron-hole recombination rate, and heterogeneous interfaces.

  11. Ultrafast all-optical switching and error-free 10 Gbit/s wavelength conversion in hybrid InP-silicon on insulator nanocavities using surface quantum wells

    SciTech Connect

    Bazin, Alexandre; Monnier, Paul; Beaudoin, Grégoire; Sagnes, Isabelle; Raj, Rama; Lenglé, Kevin; Gay, Mathilde; Bramerie, Laurent; Braive, Rémy; Raineri, Fabrice

    2014-01-06

    Ultrafast switching with low energies is demonstrated using InP photonic crystal nanocavities embedding InGaAs surface quantum wells heterogeneously integrated to a silicon on insulator waveguide circuitry. Thanks to the engineered enhancement of surface non radiative recombination of carriers, switching time is obtained to be as fast as 10 ps. These hybrid nanostructures are shown to be capable of achieving systems level performance by demonstrating error free wavelength conversion at 10 Gbit/s with 6 mW switching powers.

  12. Influence of light-polymerization modes on the degree of conversion and mechanical properties of resin composites: a comparative analysis between a hybrid and a nanofilled composite.

    PubMed

    da Silva, Eduardo Moreira; Poskus, Laiza Tatiana; Guimarães, José Guilherme Antunes

    2008-01-01

    This study analyzed the influence of the light polymerization mode on the degree of conversion (DC) and mechanical properties of two resin composites: a hybrid (Filtek P60) and a nanofilled composite (Filtek Supreme). The composites were light activated by three light polymerization modes (Standard-S: 650 mW/cm2 for 30 seconds; High intensity-H: 1000 mW/cm2 for 20 seconds and Gradual-G: 100 up to 1000 mW/cm2 for 10 seconds + 1000 mW/cm2 for 10 seconds). The DC (%) was measured by FT-Raman spectroscopy. Flexural strength and flexural modulus were obtained from bar-shaped specimens (1 x 2 x 10 mm) submitted to the three-point bending test. Microhardness was evaluated by Knoop indentation (KHN). Data were analyzed by ANOVA and Student-Newman-Keuls multiple range test and linear regression analysis. The results showed the following DC: H > S > G (p < 0.0001) and hybrid > nanofilled (p < 0.005). Correlation was found between DC and the radiant exposure (R2 = 0.92). With respect to mechanical properties, only KHN was significantly influenced by the light polymerization mode, as follow: H > S = G (p < 0.0001). The hybrid composite presented higher flexural strength and flexural modulus than the nanofilled composite (p < 0.0001). No significant difference was found in KHN between thetwo composites (p = 0.1605). The results suggest that nanofilled composites may present a lower degree of conversion and reduced mechanical properties compared to hybrid composites.

  13. All-optical NRZ wavelength conversion based on a single hybrid III-V/Si SOA and optical filtering.

    PubMed

    Wu, Yingchen; Huang, Qiangsheng; Keyvaninia, Shahram; Katumba, Andrew; Zhang, Jing; Xie, Weiqiang; Morthier, Geert; He, Jian-Jun; Roelkens, Gunther

    2016-09-05

    We demonstrate all-optical wavelength conversion (AOWC) of non-return-to-zero (NRZ) signal based on cross-gain modulation in a single heterogeneously integrated III-V-on-silicon semiconductor optical amplifier (SOA) with an optical bandpass filter. The SOA is 500 μm long and consumes less than 250 mW electrical power. We experimentally demonstrate 12.5 Gb/s and 40 Gb/s AOWC for both wavelength up and down conversion.

  14. Biomineralization-Inspired Preparation of Zinc Hydroxide Carbonate/Polymer Hybrids and Their Conversion into Zinc Oxide Thin-Film Photocatalysts.

    PubMed

    Matsumura, Shunichi; Horiguchi, Yoshimasa; Nishimura, Tatsuya; Sakai, Hideki; Kato, Takashi

    2016-05-17

    The development of ZnO thin films has been achieved through the conversion of zinc hydroxide carbonate thin-film crystals. Crystallization of this compound is induced by a biomineralization-inspired method with polymer-stabilized amorphous precursors. The crystals grow radially on polymer matrices, leading to the formation of zinc hydroxide carbonate/polymer thin-film hybrids that fully cover the substrate. These hybrids are converted into ZnO and retain their thin-film morphologies. The resultant ZnO thin films exhibit a preferential crystallographic orientation that is attributed to the alignment of zinc hydroxide carbonate crystals before conversion. In addition, a photocatalytic function of the ZnO thin films has been demonstrated by analyzing the oxidation reaction of 2-propanol. The biomineralization-inspired approach reported herein is a promising way to develop ZnO materials with controlled morphologies and structures for photocatalytic applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Block copolymer based composition and morphology control in nanostructured hybrid materials for energy conversion and storage: solar cells, batteries, and fuel cells.

    PubMed

    Orilall, M Christopher; Wiesner, Ulrich

    2011-02-01

    The development of energy conversion and storage devices is at the forefront of research geared towards a sustainable future. However, there are numerous issues that prevent the widespread use of these technologies including cost, performance and durability. These limitations can be directly related to the materials used. In particular, the design and fabrication of nanostructured hybrid materials is expected to provide breakthroughs for the advancement of these technologies. This tutorial review will highlight block copolymers as an emerging and powerful yet affordable tool to structure-direct such nanomaterials with precise control over structural dimensions, composition and spatial arrangement of materials in composites. After providing an introduction to materials design and current limitations, the review will highlight some of the most recent examples of block copolymer structure-directed nanomaterials for photovoltaics, batteries and fuel cells. In each case insights are provided into the various underlying fundamental chemical, thermodynamic and kinetic formation principles enabling general and relatively inexpensive wet-polymer chemistry methodologies for the efficient creation of multiscale functional materials. Examples include nanostructured ceramics, ceramic-carbon composites, ceramic-carbon-metal composites and metals with morphologies ranging from hexagonally arranged cylinders to three-dimensional bi-continuous cubic networks. The review ends with an outlook towards the synthesis of multicomponent and hierarchical multifunctional hybrid materials with different nano-architectures from self-assembly of higher order blocked macromolecules which may ultimately pave the way for the further development of energy conversion and storage devices.

  16. Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)/GaAs hybrid solar cells with 13% power conversion efficiency using front- and back-surface field.

    PubMed

    Lin, C H; Sun, K W; Liu, Q M; Shirai, H; Lee, C P

    2015-09-21

    Planar hybrid solar cells based on bulk GaAs wafers with a background doping density of 10(16) cm(-3) and poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) ( PSS) demonstrated an excellent power conversion efficiency of 8.99%. The efficiency of the cell was enhanced to 9.87% with a back-surface field feature using a molecular beam epitaxially grown n-type GaAs epi-layer. The efficiency and fill factor reach 11.86% and 0.8 when an additional p + GaAs epi-layer is deposited on the surface of the solar cells, which provides a front-surface field. The interface between the high- and low-doped regions in the polymer/GaAs and GaAs formed an electric field that introduced a barrier to minority carriers flow to the substrate and effectively reduced front surface carrier recombination, thereby enhancing light-generated free carrier collection efficiency and open-circuit voltage. Compared with the device without the front- and back-surface field, the fill factor and open-circuit voltage of the hybrid solar cell were improved from 0.76 to 0.8 and from 0.68 V to 0.77V, respectively. The highest efficiency reaches a record 13% when the Zonyl fluorosurfactant-treated PSS is used as a hole-transporting conducting layer for hybrid cells.

  17. Organ and effective dose conversion coefficients for a sitting female hybrid computational phantom exposed to monoenergetic protons in idealized irradiation geometries.

    PubMed

    Alves, M C; Santos, W S; Lee, Choonsik; Bolch, Wesley E; Hunt, John G; Carvalho Júnior, A B

    2014-12-21

    The conversion coefficients (CCs) relate protection quantities, mean absorbed dose (DT) and effective dose (E), with physical radiation field quantities, such as fluence (Φ). The calculation of CCs through Monte Carlo simulations is useful for estimating the dose in individuals exposed to radiation. The aim of this work was the calculation of conversion coefficients for absorbed and effective doses per fluence (DT/ Φ and E/Φ) using a sitting and standing female hybrid phantom (UFH/NCI) exposure to monoenergetic protons with energy ranging from 2 MeV to 10 GeV. The radiation transport code MCNPX was used to develop exposure scenarios implementing the female UFH/NCI phantom in sitting and standing postures. Whole-body irradiations were performed using the recommended irradiation geometries by ICRP publication 116 (AP, PA, RLAT, LLAT, ROT and ISO). In most organs, the conversion coefficients DT/Φ were similar for both postures. However, relative differences were significant for organs located in the abdominal region, such as ovaries, uterus and urinary bladder, especially in the AP, RLAT and LLAT geometries. Anatomical differences caused by changing the posture of the female UFH/NCI phantom led an attenuation of incident protons with energies below 150 MeV by the thigh of the phantom in the sitting posture, for the front-to-back irradiation, and by the arms and hands of the phantom in the standing posture, for the lateral irradiation.

  18. Organ and effective dose conversion coefficients for a sitting female hybrid computational phantom exposed to monoenergetic protons in idealized irradiation geometries

    NASA Astrophysics Data System (ADS)

    Alves, M. C.; Santos, W. S.; Lee, Choonsik; Bolch, Wesley E.; Hunt, John G.; Carvalho Júnior, A. B.

    2014-12-01

    The conversion coefficients (CCs) relate protection quantities, mean absorbed dose (DT) and effective dose (E), with physical radiation field quantities, such as fluence (Φ). The calculation of CCs through Monte Carlo simulations is useful for estimating the dose in individuals exposed to radiation. The aim of this work was the calculation of conversion coefficients for absorbed and effective doses per fluence (DT/ Φ and E/Φ) using a sitting and standing female hybrid phantom (UFH/NCI) exposure to monoenergetic protons with energy ranging from 2 MeV to 10 GeV. The radiation transport code MCNPX was used to develop exposure scenarios implementing the female UFH/NCI phantom in sitting and standing postures. Whole-body irradiations were performed using the recommended irradiation geometries by ICRP publication 116 (AP, PA, RLAT, LLAT, ROT and ISO). In most organs, the conversion coefficients DT/Φ were similar for both postures. However, relative differences were significant for organs located in the abdominal region, such as ovaries, uterus and urinary bladder, especially in the AP, RLAT and LLAT geometries. Anatomical differences caused by changing the posture of the female UFH/NCI phantom led an attenuation of incident protons with energies below 150 MeV by the thigh of the phantom in the sitting posture, for the front-to-back irradiation, and by the arms and hands of the phantom in the standing posture, for the lateral irradiation.

  19. ZnSe·0.5N2H4 hybrid nanostructures: a promising alternative photocatalyst for solar conversion.

    PubMed

    Chen, Yu-Chih; Liu, Tao-Cheng; Hsu, Yung-Jung

    2015-01-28

    As the molecular precursor of ZnSe, ZnSe·0.5N2H4 inorganic-organic hybrids have received relatively less attention due to the feasibility of their further processing and decomposition into pure-phase ZnSe. Here we demonstrated that ZnSe·0.5N2H4 hybrid nanostructures, which were prepared using a facile hydrazine-assisted hydrothermal method, may practically harvest solar energy for photoconversion applications. By modulating the volume ratio of hydrazine hydrate to deionized water employed in the synthesis, the morphology of the grown ZnSe·0.5N2H4 can be varied, which included nanowires, nanobelts and nanoflakes. With the relatively long exciton lifetime and highly anisotropic structure, ZnSe·0.5N2H4 nanowires performed much better in the photodegradation of rhodamine B than the other two counterpart products. As compared to pure ZnSe nanoparticles and single-phase ZnSe nanowires obtained from further processing ZnSe·0.5N2H4, the ZnSe·0.5N2H4 hybrid nanowires exhibited superior photocatalytic performance under visible light illumination. The hybrid nanowires were further decorated with Au particles to endow them with structural and compositional diversities. Time-resolved photoluminescence spectra suggested that almost 40% of the photoexcited electrons in ZnSe·0.5N2H4 nanowires can be transported to the decorated Au, which enabled a fuller extent of participation of charge carriers in the photocatalytic process and thus conduced to a significant enhancement in the photocatalytic activity. The demonstrations from this work illustrate that ZnSe·0.5N2H4 hybrid nanostructures can serve as a versatile photocatalyst platform for advanced photocatalytic applications.

  20. Hybridizing Conversational and Clear Speech to Investigate the Source of Increased Intelligibility in Speakers with Parkinson's Disease

    ERIC Educational Resources Information Center

    Tjaden, Kris; Kain, Alexander; Lam, Jennifer

    2014-01-01

    Purpose: A speech analysis-resynthesis paradigm was used to investigate segmental and suprasegmental acoustic variables explaining intelligibility variation for 2 speakers with Parkinson's disease (PD). Method: Sentences were read in conversational and clear styles. Acoustic characteristics from clear sentences were extracted and applied to…

  1. Hybridizing Conversational and Clear Speech to Investigate the Source of Increased Intelligibility in Speakers with Parkinson's Disease

    ERIC Educational Resources Information Center

    Tjaden, Kris; Kain, Alexander; Lam, Jennifer

    2014-01-01

    Purpose: A speech analysis-resynthesis paradigm was used to investigate segmental and suprasegmental acoustic variables explaining intelligibility variation for 2 speakers with Parkinson's disease (PD). Method: Sentences were read in conversational and clear styles. Acoustic characteristics from clear sentences were extracted and applied to…

  2. Analysis of 62 hybrid assembled human Y chromosomes exposes rapid structural changes and high rates of gene conversion

    PubMed Central

    Schierup, Mikkel Heide

    2017-01-01

    The human Y-chromosome does not recombine across its male-specific part and is therefore an excellent marker of human migrations. It also plays an important role in male fertility. However, its evolution is difficult to fully understand because of repetitive sequences, inverted repeats and the potentially large role of gene conversion. Here we perform an evolutionary analysis of 62 Y-chromosomes of Danish descent sequenced using a wide range of library insert sizes and high coverage, thus allowing large regions of these chromosomes to be well assembled. These include 17 father-son pairs, which we use to validate variation calling. Using a recent method that can integrate variants based on both mapping and de novo assembly, we genotype 10898 SNVs and 2903 indels (max length of 27241 bp) in our sample and show by father-son concordance and experimental validation that the non-recurrent SNP and indel variation on the Y chromosome tree is called very accurately. This includes variation called in a 0.9 Mb centromeric heterochromatic region, which is by far the most variable in the Y chromosome. Among the variation is also longer sequence-stretches not present in the reference genome but shared with the chimpanzee Y chromosome. We analyzed 2.7 Mb of large inverted repeats (palindromes) for variation patterns among the two palindrome arms and identified 603 mutation and 416 gene conversions events. We find clear evidence for GC-biased gene conversion in the palindromes (and a balancing AT mutation bias), but irrespective of this, also a strong bias towards gene conversion towards the ancestral state, suggesting that palindromic gene conversion may alleviate Muller’s ratchet. Finally, we also find a large number of large-scale gene duplications and deletions in the palindromic regions (at least 24) and find that such events can consist of complex combinations of simultaneous insertions and deletions of long stretches of the Y chromosome. PMID:28846694

  3. Analysis of 62 hybrid assembled human Y chromosomes exposes rapid structural changes and high rates of gene conversion.

    PubMed

    Skov, Laurits; Schierup, Mikkel Heide

    2017-08-01

    The human Y-chromosome does not recombine across its male-specific part and is therefore an excellent marker of human migrations. It also plays an important role in male fertility. However, its evolution is difficult to fully understand because of repetitive sequences, inverted repeats and the potentially large role of gene conversion. Here we perform an evolutionary analysis of 62 Y-chromosomes of Danish descent sequenced using a wide range of library insert sizes and high coverage, thus allowing large regions of these chromosomes to be well assembled. These include 17 father-son pairs, which we use to validate variation calling. Using a recent method that can integrate variants based on both mapping and de novo assembly, we genotype 10898 SNVs and 2903 indels (max length of 27241 bp) in our sample and show by father-son concordance and experimental validation that the non-recurrent SNP and indel variation on the Y chromosome tree is called very accurately. This includes variation called in a 0.9 Mb centromeric heterochromatic region, which is by far the most variable in the Y chromosome. Among the variation is also longer sequence-stretches not present in the reference genome but shared with the chimpanzee Y chromosome. We analyzed 2.7 Mb of large inverted repeats (palindromes) for variation patterns among the two palindrome arms and identified 603 mutation and 416 gene conversions events. We find clear evidence for GC-biased gene conversion in the palindromes (and a balancing AT mutation bias), but irrespective of this, also a strong bias towards gene conversion towards the ancestral state, suggesting that palindromic gene conversion may alleviate Muller's ratchet. Finally, we also find a large number of large-scale gene duplications and deletions in the palindromic regions (at least 24) and find that such events can consist of complex combinations of simultaneous insertions and deletions of long stretches of the Y chromosome.

  4. Gene conversion at the gray locus of Sordaria fimicola: fit of the experimental data to a hybrid DNA model of recombination.

    PubMed

    Kalogeropoulos, A; Thuriaux, P

    1985-03-01

    A hybrid DNA (hDNA) model of recombination has been algebraically formulated, which allows the prediction of frequencies of postmeiotic segregation and conversion of a given allele and their probability of being associated with a crossing over. The model considered is essentially the "Aviemore model." In contrast to some other interpretations of recombination, it states that gene conversion can only result from the repair of heteroduplex hDNA, with postmeiotic segregation resulting from unrepaired heteroduplexes. The model also postulates that crossing over always occurs distally to the initiation site of the hDNA. Eleven types of conversion and postmeiotic segregation with or without associated crossover were considered. Their theoretical frequencies are given by 11 linear equations with ten variables, four describing heteroduplex repair, four giving the probability of hDNA formation and its topological properties and two giving the probability that crossing over occurs at the left or right of the converting allele. Using the experimental data of Kitani and coworkers on conversion at the six best studied gray alleles of Sordaria fimicola, we found that the model considered fit the data at a P level above or very close (allele h4) to the 5% level of sampling error provided that the hDNA is partly asymmetric. The best fitting solutions are such that the hDNA has an equal probability of being formed on either chromatid or, alternatively, that both DNA strands have the same probability of acting as the invading strand during hDNA formation. The two mismatches corresponding to a given allele are repaired with different efficiencies. Optimal solutions are found if one allows for repair to be more efficient on the asymmetric hDNA than on the symmetric one. In the case of allele g1, our data imply that the direction of repair is nonrandom with respect to the strand on which it occurs.

  5. Gene Conversion at the Gray Locus of SORDARIA FIMICOLA: Fit of the Experimental Data to a Hybrid DNA Model of Recombination

    PubMed Central

    Kalogeropoulos, Angelos; Thuriaux, Pierre

    1985-01-01

    A hybrid DNA (hDNA) model of recombination has been algebraically formulated, which allows the prediction of frequencies of postmeiotic segregation and conversion of a given allele and their probability of being associated with a crossing over. The model considered is essentially the "Aviemore model." In contrast to some other interpretations of recombination, it states that gene conversion can only result from the repair of heteroduplex hDNA, with postmeiotic segregation resulting from unrepaired heteroduplexes. The model also postulates that crossing over always occurs distally to the initiation site of the hDNA. Eleven types of conversion and postmeiotic segregation with or without associated crossover were considered. Their theoretical frequencies are given by 11 linear equations with ten variables, four describing heteroduplex repair, four giving the probability of hDNA formation and its topological properties and two giving the probability that crossing over occurs at the left or right of the converting allele.—Using the experimental data of Kitani and coworkers on conversion at the six best studied gray alleles of Sordaria fimicola, we found that the model considered fit the data at a P level above or very close (allele h4) to the 5% level of sampling error provided that the hDNA is partly asymmetric. The best fitting solutions are such that the hDNA has an equal probability of being formed on either chromatid or, alternatively, that both DNA strands have the same probability of acting as the invading strand during hDNA formation. The two mismatches corresponding to a given allele are repaired with different efficiencies. Optimal solutions are found if one allows for repair to be more efficient on the asymmetric hDNA than on the symmetric one. In the case of allele g1, our data imply that the direction of repair is nonrandom with respect to the strand on which it occurs. PMID:3979816

  6. Thermal conversion of core-shell metal-organic frameworks: a new method for selectively functionalized nanoporous hybrid carbon.

    PubMed

    Tang, Jing; Salunkhe, Rahul R; Liu, Jian; Torad, Nagy L; Imura, Masataka; Furukawa, Shuhei; Yamauchi, Yusuke

    2015-02-04

    Core-shell structured ZIF-8@ZIF-67 crystals are well-designed and prepared through a seed-mediated growth method. After thermal treatment of ZIF-8@ZIF-67 crystals, we obtain selectively functionalized nanoporous hybrid carbon materials consisting of nitrogen-doped carbon (NC) as the cores and highly graphitic carbon (GC) as the shells. This is the first example of the integration of NC and GC in one particle at the nanometer level. Electrochemical data strongly demonstrate that this nanoporous hybrid carbon material integrates the advantageous properties of the individual NC and GC, exhibiting a distinguished specific capacitance (270 F·g(-1)) calculated from the galvanostatic charge-discharge curves at a current density of 2 A·g(-1). Our study not only bridges diverse carbon-based materials with infinite metal-organic frameworks but also opens a new avenue for artificially designed nanoarchitectures with target functionalities.

  7. Reaction Kinetics of Monomeric Anthocyanin Conversion to Polymeric Pigments and Their Significance to Color in Interspecific Hybrid Wines.

    PubMed

    Burtch, Claire E; Mansfield, Anna Katharine; Manns, David C

    2017-02-15

    The color stability of red wines produced from interspecific hybrid grapes, which is partially dependent on anthocyanin diglucosides, is not well understood. In this study, the rate of decrease of monomeric anthocyanins as they polymerized to polymeric pigments due to the presence of excess catechin and acetaldehyde was measured in model wine using HPLC. Colorimetry was used to measure L*, a*, and b* values, hue angle, and change in color (ΔE). Concentrations of individual diglucosides decreased more slowly than monoglucosides. When monoglucosides and diglucosides were combined, the reaction rate of monoglucosides was slower than that of monoglucosides alone. Hue angles described transitions from red to red-orange, orange, or orange-yellow as anthocyanin-specific changes occurred. The evolution in color represents dynamic reactions between anthocyanins, catechin, and acetaldehyde. Consequently, wines containing high concentrations of diglucosides, such as those produced from interspecific hybrid grapes, will form less polymeric pigment than wines containing primarily monoglucosides.

  8. Single-Step Conversion of Cells to Retrovirus Vector Producers with Herpes Simplex Virus–Epstein-Barr Virus Hybrid Amplicons

    PubMed Central

    Sena-Esteves, Miguel; Saeki, Yoshinaga; Camp, Sara M.; Chiocca, E. Antonio; Breakefield, Xandra O.

    1999-01-01

    We report here on the development and characterization of a novel herpes simplex virus type 1 (HSV-1) amplicon-based vector system which takes advantage of the host range and retention properties of HSV–Epstein-Barr virus (EBV) hybrid amplicons to efficiently convert cells to retrovirus vector producer cells after single-step transduction. The retrovirus genes gag-pol and env (GPE) and retroviral vector sequences were modified to minimize sequence overlap and cloned into an HSV-EBV hybrid amplicon. Retrovirus expression cassettes were used to generate the HSV-EBV-retrovirus hybrid vectors, HERE and HERA, which code for the ecotropic and the amphotropic envelopes, respectively. Retrovirus vector sequences encoding lacZ were cloned downstream from the GPE expression unit. Transfection of 293T/17 cells with amplicon plasmids yielded retrovirus titers between 106 and 107 transducing units/ml, while infection of the same cells with amplicon vectors generated maximum titers 1 order of magnitude lower. Retrovirus titers were dependent on the extent of transduction by amplicon vectors for the same cell line, but different cell lines displayed varying capacities to produce retrovirus vectors even at the same transduction efficiencies. Infection of human and dog primary gliomas with this system resulted in the production of retrovirus vectors for more than 1 week and the long-term retention and increase in transgene activity over time in these cell populations. Although the efficiency of this system still has to be determined in vivo, many applications are foreseeable for this approach to gene delivery. PMID:10559361

  9. Size- and shape-controlled conversion of tungstate-based inorganic-organic hybrid belts to WO3 nanoplates with high specific surface areas.

    PubMed

    Chen, Deliang; Gao, Lian; Yasumori, Atsuo; Kuroda, Kazuyuki; Sugahara, Yoshiyuki

    2008-10-01

    Two-dimensional monoclinic WO(3) nanoplates with high specific surface areas are synthesized through a novel conversion process using tungstate-based inorganic-organic hybrid micro/nanobelts as precursors. The process developed involves a topochemical transformation of tungstate-based inorganic-organic hybrid belts into WO(3) nanoplates via an intermediate product of H(2)WO(4) nanoplates, utilizing the similarity of the W-O octahedral layers in both H(2)WO(4) and WO(3). The as-obtained WO(3) nanoplates show a single-crystalline nanostructure with the smallest side along the [001] direction. The WO(3) nanoplates are 200-500 nm x 200-500 nm x 10-30 nm in size, and their specific surface areas are up to 180 m(2) g(-1). Photocatalytic measurements of visible-light-driven oxidation of water for O(2) generation in the presence of Ag(+) ions indicate that the activity of the as-obtained WO(3) nanoplates is one order of magnitude higher than that of commercially available WO(3) powders.

  10. Influence of upper hybrid resonance localized oscillation on X-B mode conversion efficiency for high-β National Spherical Torus Experiment in nonlinear regime

    NASA Astrophysics Data System (ADS)

    Abbasi, M.; Ali Asgarian, M.; Sobhanian, S.; Sadeghi, Y.

    2015-06-01

    Ever increasing needs and capabilities in high power radio frequency waves heating and current drive scenarios of present and future magnetic confined fusion plasmas motivate expansion of understanding for vast variety of ever upcoming nonlinearities in such levels of power. Among many motivating experiments, one of the most relevant and actively studied in the regime for electron Bernstein wave (EBW) heating is high-β National Spherical Torus Experiment. A very special type of large amplitude electron plasma oscillations known as localized upper hybrid (UH) mode is demonstrated. It is shown that the mutual synergetic interaction of EBW and the localized UH mode can significantly shift the resonance layer about △ x ˜ 0.9 mm compared to the prediction of linear theory and consequently can explain the considerable reduction of conversion value around 35% observed in our modelling. This reduction is due to scale up of density scale length, L n , at the new UH resonance (UHR) location followed by the increase of Budden parameter, η, which varies from 0.18 predicted by linear aspect to 0.40 in new position of UHR layer obtained by our modelling. Moreover, the parametric instabilities in the form of ion decays and dispersion of localized UH mode, approximately 7 mm due to the finite electron temperature account, are also observed which have an important contribution in reduction of conversion efficiency.

  11. TiO2/Sb2S3/P3HT Based Inorganic-Organic Hybrid Heterojunction Solar Cells with Enhanced Photoelectric Conversion Performance

    NASA Astrophysics Data System (ADS)

    Zhang, Hongchao; Song, Longfei; Luo, Linqu; Liu, Lei; Wang, Hongen; Wang, Fengyun

    2017-07-01

    Hybrid inorganic-organic heterojunction solar cells (HHSCs) are successfully fabricated using Sb2S3 as a light-absorbing semiconductor, TiO2 nanorods (NRs) as an electron-transport layer, and poly-3 (hexylthiophene) (P3HT) as both a hole conductor and light absorber. The enhanced photo-to-electric conversion performance is expected to (1) enhance optical absorption in the visible light region by Sb2S3 and (2) photo-generate highly efficient charge carrier separation at TiO2/Sb2S3 and Sb2S3/P3HT heterojunction interfaces. The power conversion efficiency (PCE) of HHSCs improves approximately fourfold by inserting the Sb2S3 layer, which can be further enhanced about four more times by optimizing the length of TiO2 nanorod arrays (NRAs). Finally, the mechanism to illustrate the effect of the length of TiO2 NRs on the PCE is discussed. This leads to a theory for achieving high-efficiency inorganic-organic solar cells.

  12. Toward direct light-to-digital conversion using a pulse-driven hybrid MOS-PN photodetector.

    PubMed

    Sallin, Denis; Koukab, Adil; Kayal, Maher

    2015-02-15

    In this Letter, a direct light-to-digital converter based on an MOS-PN photodetector driven by pulsed voltage is presented. The objective is to avoid any analog-to-digital or time-to-digital conversion and, thereby, to pave the way for a new generation of fully digital imaging sensors with reduced complexity, area, and power consumption. Moreover, the pulsed voltage operation allows for a significant reduction of the dark level. The concept is validated by a theoretical study and TCAD simulations. A first prototype fabricated in 0.18 μm CMOS technology is presented. The experimental results under various light conditions show that the pulsed voltage improves the light sensitivity by several orders of magnitude.

  13. NEBNext Direct: A Novel, Rapid, Hybridization-Based Approach for the Capture and Library Conversion of Genomic Regions of Interest.

    PubMed

    Emerman, Amy B; Bowman, Sarah K; Barry, Andrew; Henig, Noa; Patel, Kruti M; Gardner, Andrew F; Hendrickson, Cynthia L

    2017-07-05

    Next-generation sequencing (NGS) is a powerful tool for genomic studies, translational research, and clinical diagnostics that enables the detection of single nucleotide polymorphisms, insertions and deletions, copy number variations, and other genetic variations. Target enrichment technologies improve the efficiency of NGS by only sequencing regions of interest, which reduces sequencing costs while increasing coverage of the selected targets. Here we present NEBNext Direct(®) , a hybridization-based, target-enrichment approach that addresses many of the shortcomings of traditional target-enrichment methods. This approach features a simple, 7-hr workflow that uses enzymatic removal of off-target sequences to achieve a high specificity for regions of interest. Additionally, unique molecular identifiers are incorporated for the identification and filtering of PCR duplicates. The same protocol can be used across a wide range of input amounts, input types, and panel sizes, enabling NEBNext Direct to be broadly applicable across a wide variety of research and diagnostic needs. © 2017 by John Wiley & Sons, Inc. Copyright © 2017 John Wiley & Sons, Inc.

  14. High-performance direct conversion X-ray detectors based on sintered hybrid lead triiodide perovskite wafers

    NASA Astrophysics Data System (ADS)

    Shrestha, Shreetu; Fischer, René; Matt, Gebhard J.; Feldner, Patrick; Michel, Thilo; Osvet, Andres; Levchuk, Ievgen; Merle, Benoit; Golkar, Saeedeh; Chen, Haiwei; Tedde, Sandro F.; Schmidt, Oliver; Hock, Rainer; Rührig, Manfred; Göken, Mathias; Heiss, Wolfgang; Anton, Gisela; Brabec, Christoph J.

    2017-07-01

    Lead halide perovskite semiconductors are in general known to have an inherently high X-ray absorption cross-section and a significantly higher carrier mobility than any other low-temperature solution-processed semiconductor. So far, the processing of several-hundred-micrometres-thick high-quality crystalline perovskite films over a large area has been unresolved for efficient X-ray detection. In this Article, we present a mechanical sintering process to fabricate polycrystalline methyl ammonium lead triiodide perovskite (MAPbI3) wafers with millimetre thickness and well-defined crystallinity. Benchmarking of the MAPbI3 wafers against state-of-the-art CdTe detectors reveals competitive conversion efficiencies of 2,527 µC Gyair-1 cm-2 under 70 kVp X-ray exposure. The high ambipolar mobility-lifetime product of 2 × 10-4 cm2 V-1 is suggested to be responsible for this exceptionally high sensitivity. Our findings inform a new generation of highly efficient and low-cost X-ray detectors based on perovskite wafers.

  15. Highly Active 2D Layered MoS 2 -rGO Hybrids for Energy Conversion and Storage Applications.

    PubMed

    Kamila, Swagatika; Mohanty, Bishnupad; Samantara, Aneeya K; Guha, Puspendu; Ghosh, Arnab; Jena, Bijayalaxmi; Satyam, Parlapalli V; Mishra, B K; Jena, Bikash Kumar

    2017-08-21

    The development of efficient materials for the generation and storage of renewable energy is now an urgent task for future energy demand. In this report, molybdenum disulphide hollow sphere (MoS2-HS) and its reduced graphene oxide hybrid (rGO/MoS2-S) have been synthesized and explored for energy generation and storage applications. The surface morphology, crystallinity and elemental composition of the as-synthesized materials have been thoroughly analysed. Inspired by the fascinating morphology of the MoS2-HS and rGO/MoS2-S materials, the electrochemical performance towards hydrogen evolution and supercapacitor has been demonstrated. The rGO/MoS2-S shows enhanced gravimetric capacitance values (318 ± 14 Fg(-1)) with higher specific energy/power outputs (44.1 ± 2.1 Whkg(-1) and 159.16 ± 7.0 Wkg(-1)) and better cyclic performances (82 ± 0.95% even after 5000 cycles). Further, a prototype of the supercapacitor in a coin cell configuration has been fabricated and demonstrated towards powering a LED. The unique balance of exposed edge site and electrical conductivity of rGO/MoS2-S shows remarkably superior HER performances with lower onset over potential (0.16 ± 0.05 V), lower Tafel slope (75 ± 4 mVdec(-1)), higher exchange current density (0.072 ± 0.023 mAcm(-2)) and higher TOF (1.47 ± 0.085 s(-1)) values. The dual performance of the rGO/MoS2-S substantiates the promising application for hydrogen generation and supercapacitor application of interest.

  16. Hybrid chromophore/template nanostructures: a customizable platform material for emissions-free solar energy storage and conversion

    NASA Astrophysics Data System (ADS)

    Kolpak, Alexie

    2012-03-01

    By reversibly storing solar energy in the conformations of molecular photo-isomers, solar thermal fuels (STFs) provide a mechanism for emissions-free, renewable energy storage and conversion, all in a single system. Development of STFs as a large-scale clean energy technology, however, has been hampered by a number of technical challenges that beset many of the photo-isomers of interest. These challenges include low energy density, short storage lifetime, and low quantum yield of the photoisomerization reaction; a small overlap with the solar spectrum; and the irreversible degradation of the photo-active molecules upon repeated cycling. In this talk, I will discuss my work using first-principles computations to design new STFs that overcome these technical hurdles. I will present computational results on a range of novel STFs based on our recently proposed photo-isomer/template nanostructure concept [Kolpak and Grossman, Nano Letters 11, 3156 (2011)], illustrating that this approach enables enormous improvements with respect to the potential STFs studied in the past, leading to STFs with energy densities in the range of Li-ion batteries, storage lifetimes of up to a year, and increased quantum yield and absorption efficiency. I will also discuss preliminary experimental results on the synthesis and characterization of one of the predicted STFs based on azobenzene-derivitized carbon nanotubes. With a large range of the photo-isomer/template phase space yet to be explored, there are numerous exciting possibilites for further property enhancement and customization, suggesting that STFs could become a competitive renewable energy technology.

  17. Bio-template route for facile fabrication of Cd(OH){sub 2}@yeast hybrid microspheres and their subsequent conversion to mesoporous CdO hollow microspheres

    SciTech Connect

    Bai, Bo; Guan, Weisheng; Li, Ziyan; Li Puma, Gianluca

    2011-01-15

    Cadmium oxide (CdO) microspheres with a porous hollow microstructure were prepared by a facile yeast mediated bio-template route. The yeast provides a solid scaffold for the deposition of cadmium hydroxide (Cd(OH){sub 2}) from cadmium acetate and sodium hydroxide solutions to form the hybrid Cd(OH){sub 2}@yeast precursor. Thermal conversions of this at above 500 {sup o}C in air have produced hollow CdO microspheres. The products were characterized by scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FT-IR), thermal gravimetric and differential thermal analysis (TGA-DTA), and Brunauer-Emmett-Teller (BET) surface analysis respectively. The obtained CdO microspheres have uniform size (length = 2.6 {+-} 0.4 {mu}m; width = 2.0 {+-} 0.2 {mu}m) and a well defined, continuous, mesoporous hollow microstructure. The shell is about 250-280 nm in thickness. The mechanism of formation of Cd(OH){sub 2}@yeast precursor and its conversion to CdO hollow microspheres is discussed. In comparison with traditional template-directed method, the present strategy represents a general, economical and environmentally benign route for the formation of metal oxide hollow microspheres. These materials have potential applications in different fields such as encapsulation, drug delivery, efficient catalysis, battery materials and photonic crystals. The method presented can be extended to the synthesis of other inorganic hollow microstructures of different sizes and shapes by pre-selecting suitable bio-templates.

  18. Novel light-conversion hybrids of SBA-16 functionalized with rare earth (Eu3+, Nd3+, Yb3+) complexes of modified 2-methyl-9-hydroxyphenalenone and 1,10-phenanthroline

    NASA Astrophysics Data System (ADS)

    Gu, Yan-Jing; Yan, Bing; Qiao, Xiao-Fei

    2013-03-01

    Novel rare earth complex-functionalized mesoporous SBA-16-type hybrid materials are synthesized by the co-condensation of modified 2-methyl-9-hydroxyphenalenone (MHPOSi), from modified 3-(triethoxysilyl)-propyl isocyanate (TEPIC), and tetraethoxysilane (TEOS) in the presence of Pluronic F127 as a template. These inorganic-organic mesoporous hybrids are characterized by FT-IR spectra, small-angle X-ray diffraction (SAXRD), N2 adsorption-desorption measurements, thermal analysis and spectroscopy. Their photophysical properties, which show novel light conversion properties, are discussed in detail. The Eu3+ hybrid system shows ultraviolet excitation and visible emission, and the Nd+ and Yb3+ hybrids exhibit visible excitation and NIR emission.

  19. Planar CH3NH3PbBr3 hybrid solar cells with 10.4% power conversion efficiency, fabricated by controlled crystallization in the spin-coating process.

    PubMed

    Heo, Jin Hyuck; Song, Dae Ho; Im, Sang Hyuk

    2014-12-23

    A power conversion efficiency of 10.4% is demonstrated in planar CH3 NH3 PbBr3 hybrid solar cells without hysteresis of the J-V curve, by way of controlled crystallization in the spin-coating process. The high efficiency is attributed to the formation of a dense CH3 NH3 PbBr3 thin film by the introduction of HBr solution because the HBr increases the solubility of the CH3 NH3 PbBr3 and forms a thinner CH3 NH3 PbBr3 layer with full surface coverage.

  20. Up-conversion cell imaging and pH-induced thermally controlled drug release from NaYF4/Yb3+/Er3+@hydrogel core-shell hybrid microspheres.

    PubMed

    Dai, Yunlu; Ma, Ping'an; Cheng, Ziyong; Kang, Xiaojiao; Zhang, Xiao; Hou, Zhiyao; Li, Chunxia; Yang, Dongmei; Zhai, Xuefeng; Lin, Jun

    2012-04-24

    In this study, we report a new controlled release system based on up-conversion luminescent microspheres of NaYF(4):Yb(3+)/Er(3+) coated with the smart hydrogel poly[(N-isopropylacrylamide)-co-(methacrylic acid)] (P(NIPAM-co-MAA)) (prepared using 5 mol % of MAA) shell. The hybrid microspheres show bright up-conversion fluorescence under 980 nm laser excitation, and turbidity measurements show that the low critical solution temperature of the polymer shell is thermo- and pH-dependent. We have exploited the hybrid microspheres as carriers for Doxorubicin hydrochloride (DOX) due to its stimuli-responsive property as well as good biocompatibility via MTT assay. It is found that the drug release behavior is pH-triggered thermally sensitive. Changing the pH to mildly acidic condition at physiological temperature deforms the structure of the shell, causing the release of a large number of DOX from the microspheres. The drug-loaded microspheres exhibit an obvious cytotoxic effect on SKOV3 ovarian cancer cells. The endocytosis process of drug-loaded microspheres is observed using confocal laser scanning microscopy and up-conversion luminescence microscopy. Meanwhile, the as-prepared NaYF(4):Yb(3+)/Er(3+)@SiO(2)@P(NIPAM-co-MAA) microspheres can be used as a luminescent probe for cell imaging. In addition, the extent of drug release can be monitored by the change of up-conversion emission intensity. These pH-induced thermally controlled drug release systems have potential to be used for in vivo bioimaging and cancer therapy by the pH of the microenvironment changing from 7.4 (normal physiological environment) to acidic microenvironments (such as endosome and lysosome compartments) owing to endocytosis.

  1. Conversational Dominance.

    ERIC Educational Resources Information Center

    Esau, Helmut; Poth, Annette

    Details of conversational behavior can often not be interpreted until the social interaction, including the rights and obligations of the participants, their intent, the topic, etc., has been defined. This paper presents a model of conversation in which the conversational image a person presents in a given conversational situation is a function of…

  2. A comparison study of aliphatic and aromatic structure directing agents influencing the crystal and electronic structures, and properties of iodoplumbate hybrids: water induced structure conversion and visible light photocatalytic properties.

    PubMed

    Liu, Guang-Ning; Shi, Jian-Ru; Han, Xiao-Jiang; Zhang, Xiao; Li, Ke; Li, Jie; Zhang, Tao; Liu, Qi-Sheng; Zhang, Zhen-Wei; Li, Cuncheng

    2015-07-28

    The introduction of the aliphatic amines en (ethylenediamine), aep (N-(2-aminoethyl)piperazine) and tepa (tetraethylenepentamine), and the aromatic species 2,2'-bipy (2,2'-bipyridine) and dpe (1,2-di(4-pyridyl)ethylene) as structure directing agents (SDAs) into inorganic iodoplumbates affords six hybrids, namely [(Hen)4(H2.5O)2I](PbI6) (1), Cs2n[Pb3I8(en)2]n (2), (H3tepa)n(PbI5)n (3), (H2aep)n(PbI4)n (4), (Et22,2'-bipy)n(Pb2I6)n (5) and (Et2dpe)n(Pb2I6)n (6). 1 contains a discrete octahedral (PbI6)(4-) anion generated under the direction of a novel co-template, [(Hen)4(H2.5O)2I](4+). 2 contains inorganic Cs(+) ions and a novel hybrid anionic layer [Pb3I8(en)2]n(2n-) that has never been encountered in iodoplumbate hybrids. 3 features a zigzag (PbI5)(3-) chain with the charge being compensated by a triprotonated tepa cation. 4 is composed of perovskite sheets of lead(ii) octahedra and aep cations that are generated from tepa via an unprecedented in situ ligand reaction. Both 5 and 6 have (Pb2I6)n(2n-) chains and represent the first example of introducing a 2,2'-bipy or dpe derivative cation in iodoplumbate hybrids, respectively. The comparative study reveals that aliphatic amines and aromatic species contribute differently to the crystal and electronic structures, and the properties of the hybrids. Importantly, 1-4 exhibit interesting water induced structure conversions, while 5 and 6 can be used as heterogeneous photocatalysts for dye wastewater treatment under visible light irradiation.

  3. Chemical reactions in TiO2/SnO2/TiCl4 hybrid electrodes and their impacts to power conversion efficiency of dye-sensitized solar cells

    NASA Astrophysics Data System (ADS)

    Chou, Chuen-Shii; Jhang, Jhih-Wei; Chou, Sheng-Wei; Wu, Ping

    2015-01-01

    This study examined the applicability of TiO2/SnO2/TiCl4 hybrid electrodes in dye-sensitized solar cells (DSSCs) by combining chemical modeling with experimentation. The interfacial chemical reactions in a TiO2/SnO2/TiCl4 system were simulated using a thermochemistry software package, which led to the design and testing of hybrid working electrodes. Chemical thermodynamic modeling proved that TiCl4 is an effective agent in removing Tin+ (n<4) and Snm+ (m<4) ion impurities from dry-mixed TiO2/SnO2 composite particles. Our results demonstrate that the power conversion efficiency of DSSC with a TiO2/SnO2/TiCl4 hybrid electrode exceeds that of the conventional DSSC with a TiO2 electrode due to the effects of light-scattering and the formation of additional absorbance (SnCl2), which is an unexpected side effect of TiCl4 treatment enabling the absorption of visible light. The proposed approach is ideally suited to establishing relationships between chemistry theory and the structure and performance of advanced DSSCs as well as photo-electro-chemical systems.

  4. A hybrid geothermal energy conversion technology: Auxiliary heating of geothermally preheated water or CO2 - a potential solution for low-temperature resources

    NASA Astrophysics Data System (ADS)

    Saar, Martin; Garapati, Nagasree; Adams, Benjamin; Randolph, Jimmy; Kuehn, Thomas

    2016-04-01

    Safe, sustainable, and economic development of deep geothermal resources, particularly in less favourable regions, often requires employment of unconventional geothermal energy extraction and utilization methods. Often "unconventional geothermal methods" is synonymously and solely used as meaning enhanced geothermal systems, where the permeability of hot, dry rock with naturally low permeability at greater depths (4-6 km), is enhanced. Here we present an alternative unconventional geothermal energy utilization approach that uses low-temperature regions that are shallower, thereby drastically reducing drilling costs. While not a pure geothermal energy system, this hybrid approach may enable utilization of geothermal energy in many regions worldwide that can otherwise not be used for geothermal electricity generation, thereby increasing the global geothermal resource base. Moreover, in some realizations of this hybrid approach that generate carbon dioxide (CO2), the technology may be combined with carbon dioxide capture and storage (CCS) and CO2-based geothermal energy utilization, resulting in a high-efficiency (hybrid) geothermal power plant with a negative carbon footprint. Typically, low- to moderate-temperature geothermal resources are more effectively used for direct heat energy applications. However, due to high thermal losses during transport, direct use requires that the heat resource is located near the user. Alternatively, we show here that if such a low-temperature geothermal resource is combined with an additional or secondary energy resource, the power production is increased compared to the sum from two separate (geothermal and secondary fuel) power plants (DiPippo et al. 1978) and the thermal losses are minimized because the thermal energy is utilized where it is produced. Since Adams et al. (2015) found that using CO2 as a subsurface working fluid produces more net power than brine at low- to moderate-temperature geothermal resource conditions, we

  5. Facile One-Step Synthesis of Hybrid Graphitic Carbon Nitride and Carbon Composites as High-Performance Catalysts for CO2 Photocatalytic Conversion.

    PubMed

    Wang, Yangang; Bai, Xia; Qin, Hengfei; Wang, Fei; Li, Yaguang; Li, Xi; Kang, Shifei; Zuo, Yuanhui; Cui, Lifeng

    2016-07-13

    Utilizing and reducing carbon dioxide is a key target in the fight against global warming. The photocatalytic performance of bulk graphitic carbon nitride (g-C3N4) is usually limited by its low surface area and rapid charge carrier recombination. To develop g-C3N4 more suitable for photocatalysis, researchers have to enlarge its surface area and accelerate the charge carrier separation. In this work, novel hybrid graphitic carbon nitride and carbon (H-g-C3N4/C) composites with various carbon contents have been developed for the first time by a facile one-step pyrolysis method using melamine and natural soybean oil as precursors. The effect of carbon content on the structure of H-g-C3N4/C composites and the catalytic activity for the photoreduction of CO2 with H2O were investigated. The results indicated that the introduction of carbon component can effectively improve the textural properties and electronic conductivity of the composites, which exhibited imporved photocatalytic activity for the reduction of CO2 with H2O in comparison with bulk g-C3N4. The highest CO and CH4 yield of 22.60 μmol/g-cat. and 12.5 μmol/g-cat., respectively, were acquired on the H-g-C3N4/C-6 catalyst with the carbon content of 3.77 wt % under 9 h simulated solar irradiation, which were more than twice as high as that of bulk g-C3N4. The remarkably increased photocatalytic performance arises from the synergistic effect of hybrid carbon and g-C3N4.

  6. Contentious Conversations

    ERIC Educational Resources Information Center

    Zuidema, Leah A.

    2011-01-01

    The idea of joining a conversation through reading and writing is not new; in his 1941 book "The Philosophy of Literary Form: Studies in Symbolic Action," Kenneth Burke suggests that the acts of reading and writing are like entering a parlor where others are already conversing. The author explores the place of professional debate within NCTE and…

  7. Contentious Conversations

    ERIC Educational Resources Information Center

    Zuidema, Leah A.

    2011-01-01

    The idea of joining a conversation through reading and writing is not new; in his 1941 book "The Philosophy of Literary Form: Studies in Symbolic Action," Kenneth Burke suggests that the acts of reading and writing are like entering a parlor where others are already conversing. The author explores the place of professional debate within NCTE and…

  8. Manipulation of Amorphous-to-Crystalline Transformation: Towards the Construction of Covalent Organic Framework Hybrid Microspheres with NIR Photothermal Conversion Ability.

    PubMed

    Tan, Jing; Namuangruk, Supawadee; Kong, Weifu; Kungwan, Nawee; Guo, Jia; Wang, Changchun

    2016-11-02

    An approach to transforming amorphous organic networks into crystalline covalent organic frameworks (COFs) with retention of the colloidal nanosize and uniform morphology is presented. Specifically, Fe3 O4 nanoclusters are encapsulated by a disordering polyimine network via the Schiff-base reaction. The formed imine bonds could be reconstructed under thermodynamic control to reform the polyimine networks into imine-linked COFs in situ. Such a core-shell microsphere exhibits the uniform size and spherical shape, controllable COF shell thickness, accessible surface modification, and improved solution dispersibility as well as maintenance of high surface area, periodic micropores, and superior magnetic responsiveness. Additionally, the photothermal conversion effect is demonstrated for the first time on the nanoCOF layers upon exposure to near infrared light, providing convincing evidence for potential use in phototherapy.

  9. Strong Enhancement of Photoelectric Conversion Efficiency of Co-hybridized Polymer Solar Cell by Silver Nanoplates and Core-Shell Nanoparticles.

    PubMed

    Shen, Wenfei; Tang, Jianguo; Wang, Yao; Liu, Jixian; Huang, Linjun; Chen, Weichao; Yang, Lanlan; Wang, Wei; Wang, Yanxin; Yang, Renqiang; Yun, Jungheum; Belfiore, Laurence A

    2017-02-15

    A new way was meticulously designed to utilize the localized surface plasmon resonance (LSPR) effect and the light scattering effect of silver nanoplate (Ag-nPl) and core-shell Ag@SiO2 nanoparticles (Ag@SiO2-NPs) to enhance the photovoltaic performances of polymer solar cells (PSCs). To prevent direct contact between silver nanoparticles (Ag-NPs) and photoactive materials which will cause electrons quenching, bare Ag-nPl were spin-coated on indium tin oxide and silica capsulated Ag-NPs were incorporated to a PBDTTT-C-T:PC71BM active layer. As a result, the devices incorporated with Ag-nPl and Ag@SiO2-NPs showed great enhancements. With the dual effects of Ag-nPl and Ag@SiO2-NPs in devices, all wavelength sensitization in the visible range was realized; therefore, the power conversion efficiency (PCE) of PSCs showed a great enhancement of 14.0% to 8.46%, with an increased short-circuit current density of 17.23 mA·cm(-2). The improved photovoltaic performances of the devices were ascribed to the LSPR effect and the light scattering effect of metallic nanoparticles. Apart from optical effects, the charge collection efficiency of PSCs was improved after the incorporation of Ag-nPl.

  10. Hybrid photocathodes for solar fuel production: coupling molecular fuel-production catalysts with solid-state light harvesting and conversion technologies

    PubMed Central

    Cedeno, Diana; Krawicz, Alexandra; Moore, Gary F.

    2015-01-01

    Artificial photosynthesis is described as the great scientific and moral challenge of our time. We imagine a future where a significant portion of our energy is supplied by such technologies. However, many scientific, engineering and policy challenges must be addressed for this realization. Scientific challenges include the development of effective strategies to couple light absorption, electron transfer and catalysis for efficient conversion of light energy to chemical energy as well as the construction and study of structurally diverse assemblies to carry out these processes. In this article, we review recent efforts from our own research to develop a modular approach to interfacing molecular fuel-production catalysts to visible-light-absorbing semiconductors and discuss the role of the interfacing material as a protection layer for the catalysts as well as the underpinning semiconductor. In concluding, we briefly discuss the potential benefits of a globally coordinated project on artificial photosynthesis that interfaces teams of scientists, engineers and policymakers. Further, we offer cautions that such a large interconnected organization should consider. This article is inspired by, and draws largely from, an invited presentation given by the corresponding author at the Royal Society at Chicheley Hall, home of the Kavli Royal Society International Centre, Buckinghamshire on the themed meeting topic: ‘Do we need a global project on artificial photosynthesis?’ PMID:26052422

  11. Hybrid photocathodes for solar fuel production: coupling molecular fuel-production catalysts with solid-state light harvesting and conversion technologies.

    PubMed

    Cedeno, Diana; Krawicz, Alexandra; Moore, Gary F

    2015-06-06

    Artificial photosynthesis is described as the great scientific and moral challenge of our time. We imagine a future where a significant portion of our energy is supplied by such technologies. However, many scientific, engineering and policy challenges must be addressed for this realization. Scientific challenges include the development of effective strategies to couple light absorption, electron transfer and catalysis for efficient conversion of light energy to chemical energy as well as the construction and study of structurally diverse assemblies to carry out these processes. In this article, we review recent efforts from our own research to develop a modular approach to interfacing molecular fuel-production catalysts to visible-light-absorbing semiconductors and discuss the role of the interfacing material as a protection layer for the catalysts as well as the underpinning semiconductor. In concluding, we briefly discuss the potential benefits of a globally coordinated project on artificial photosynthesis that interfaces teams of scientists, engineers and policymakers. Further, we offer cautions that such a large interconnected organization should consider. This article is inspired by, and draws largely from, an invited presentation given by the corresponding author at the Royal Society at Chicheley Hall, home of the Kavli Royal Society International Centre, Buckinghamshire on the themed meeting topic: 'Do we need a global project on artificial photosynthesis?'

  12. Metric Conversion

    Atmospheric Science Data Center

    2013-03-12

    ... 1,000,000 1,000,000 micrometers nano- 1,000,000,000 1,000,000,000 nanometers ... conversions, see the National Institute of Standards and Technology (NIST) Special Publications: NIST Guide to SI Units: ...

  13. Conversation Analysis.

    ERIC Educational Resources Information Center

    Schiffrin, Deborah

    1990-01-01

    Summarizes the current state of research in conversation analysis, referring primarily to six different perspectives that have developed from the philosophy, sociology, anthropology, and linguistics disciplines. These include pragmatics; speech act theory; interactional sociolinguistics; ethnomethodology; ethnography of communication; and…

  14. Comprehensive analysis of photonic effects on up-conversion of β-NaYF4:Er3+ nanoparticles in an organic-inorganic hybrid 1D photonic crystal

    NASA Astrophysics Data System (ADS)

    Hofmann, C. L. M.; Fischer, S.; Reitz, C.; Richards, B. S.; Goldschmidt, J. C.

    2016-04-01

    Upconversion (UC) presents a possibility to exploit sub-bandgap photons for current generation in solar cells by creating one high-energy photon out of at least two lower-energy photons. Photonic structures can enhance UC by two effects: a locally increased irradiance and a modified local density of photon states (LDOS). Bragg stacks are promising photonic structures for this application, because they are straightforward to optimize and overall absorption can be increased by adding more layers. In this work, we present a comprehensive simulation-based analysis of the photonic effects of a Bragg stack on UC luminescence. The investigated organic-inorganic hybrid Bragg stack consists of alternating layers of Poly(methylmethacrylate) (PMMA), containing purpose-built β-NaYF4:25% Er3+ core-shell nanoparticles and titanium dioxide (TiO2). From optical characterization of single thin layers, input parameters for simulations of the photonic effects are generated. The local irradiance enhancement and modulated LDOS are first simulated separately. Subsequently they are coupled in a rate equation model of the upconversion dynamics. Using the integrated model, UC luminescence is maximized by adapting the Bragg stack design. For a Bragg stack of only 5 bilayers, UC luminescence is enhanced by a factor of 3.8 at an incident irradiance of 2000 W/m2. Our results identify the Bragg stack as promising for enhancing UC, especially in the low-irradiance regime, relevant for the application in photovoltaics. Therefore, we experimentally realized optimized Bragg stack designs. The PMMA layers, containing UC nanoparticles, are produced via spin-coating from a toluene based solution. The TiO2 layers are produced by atomic layer deposition from molecular precursors. The reflectance measurements show that the realized Bragg stacks are in good agreement with predictions from simulation.

  15. Conversational Telugu.

    ERIC Educational Resources Information Center

    Beinstein, Judith; And Others

    The purpose of this text is to develop elementary conversational skills in Telugu. The language materials consist of four types of language learning activities. The first, and most predominant, is the unit microwave cycle. These cycles divide the learning process into two basic phases, the first of which involves mimicry, memorization, and…

  16. Conversational Tamil.

    ERIC Educational Resources Information Center

    Beinstein, Judith; And Others

    The purpose of this text is to develop conversational skills in Tamil. It is to be used as a review of what has been learned in class and not as a teaching device. The language materials consist of four types of language learning activities. The unit microwave cycle divides the learning process into two basic phases. The first phase involves…

  17. Energy conversion at dipolarization fronts

    NASA Astrophysics Data System (ADS)

    Khotyaintsev, Yu. V.; Divin, A.; Vaivads, A.; André, M.; Markidis, S.

    2017-02-01

    We use multispacecraft observations by Cluster in the Earth's magnetotail and 3-D particle-in-cell simulations to investigate conversion of electromagnetic energy at the front of a fast plasma jet. We find that the major energy conversion is happening in the Earth (laboratory) frame, where the electromagnetic energy is being transferred from the electromagnetic field to particles. This process operates in a region with size of the order several ion inertial lengths across the jet front, and the primary contribution to E·j is coming from the motional electric field and the ion current. In the frame of the front we find fluctuating energy conversion with localized loads and generators at sub-ion scales which are primarily related to the lower hybrid drift instability excited at the front; however, these provide relatively small net energy conversion.

  18. Fabrication of Heterostructured g-C3N4/Ag-TiO2 Hybrid Photocatalyst with Enhanced Performance in Photocatalytic Conversion of CO2 Under Simulated Sunlight Irradiation

    NASA Astrophysics Data System (ADS)

    Li, Hailong; Gao, Yan; Wu, Xianying; Lee, Po-Heng; Shih, Kaimin

    2017-04-01

    Heterostructured g-C3N4/Ag-TiO2 (CN/AgTi) hybrid catalysts were fabricated through a facile solvent evaporation followed by a calcination process, using graphitic carbon nitride (g-C3N4) and Ag-TiO2 (AgTi) as precursors. The phase compositions, optical properties, and morphologies of the catalysts were systematically characterized. The heterostructured combination of g-C3N4, titania (TiO2) and silver nanoparticles (Ag NPs) resulted in significant synergy for catalytic conversion of CO2 in the presence of water vapor under simulated sunlight irradiation. The optimal CN/AgTi composite with a g-C3N4 to AgTi mass ratio of 8% exhibited the maximum CO2 photoreduction activity, achieving a CO2 conversion of 47 μmol, CH4 yield of 28 μmol, and CO yield of 19 μmol per gram of catalyst during a 3 h simulated sunlight irradiation. Under the experimental conditions, the rate of electron consumption was calculated to be 87.3 μmol/g·h, which was 12.7 times, 7.9 times, and 2.0 times higher than those for TiO2, g-C3N4 and AgTi, respectively. The combination of g-C3N4 and AgTi resulted in more sunlight harvesting for electron and hole generations. Photoinduced electrons transferred through the heterjunction between g-C3N4 and TiO2, and further from TiO2 to Ag NPs with lower Fermi level greatly suppressed the recombination of electron-hole pairs, and hence resulted in electron accumulation on Ag NPs deposited on the TiO2 surface in the CN/AgTi. Abundant electrons accumulated on the Ag NPs were further energized by the surface plasmon resonance effect with the aid of visible light. Therefore, the CN/AgTi catalysts exhibited superior catalytic performance in CO2 reduction by water vapor under simulated sunlight irradiation.

  19. Conversational sensing

    NASA Astrophysics Data System (ADS)

    Preece, Alun; Gwilliams, Chris; Parizas, Christos; Pizzocaro, Diego; Bakdash, Jonathan Z.; Braines, Dave

    2014-05-01

    Recent developments in sensing technologies, mobile devices and context-aware user interfaces have made it pos- sible to represent information fusion and situational awareness for Intelligence, Surveillance and Reconnaissance (ISR) activities as a conversational process among actors at or near the tactical edges of a network. Motivated by use cases in the domain of Company Intelligence Support Team (CoIST) tasks, this paper presents an approach to information collection, fusion and sense-making based on the use of natural language (NL) and controlled nat- ural language (CNL) to support richer forms of human-machine interaction. The approach uses a conversational protocol to facilitate a ow of collaborative messages from NL to CNL and back again in support of interactions such as: turning eyewitness reports from human observers into actionable information (from both soldier and civilian sources); fusing information from humans and physical sensors (with associated quality metadata); and assisting human analysts to make the best use of available sensing assets in an area of interest (governed by man- agement and security policies). CNL is used as a common formal knowledge representation for both machine and human agents to support reasoning, semantic information fusion and generation of rationale for inferences, in ways that remain transparent to human users. Examples are provided of various alternative styles for user feedback, including NL, CNL and graphical feedback. A pilot experiment with human subjects shows that a prototype conversational agent is able to gather usable CNL information from untrained human subjects.

  20. Conversational sensemaking

    NASA Astrophysics Data System (ADS)

    Preece, Alun; Webberley, Will; Braines, Dave

    2015-05-01

    Recent advances in natural language question-answering systems and context-aware mobile apps create opportunities for improved sensemaking in a tactical setting. Users equipped with mobile devices act as both sensors (able to acquire information) and effectors (able to act in situ), operating alone or in collectives. The currently- dominant technical approaches follow either a pull model (e.g. Apple's Siri or IBM's Watson which respond to users' natural language queries) or a push model (e.g. Google's Now which sends notifications to a user based on their context). There is growing recognition that users need more flexible styles of conversational interaction, where they are able to freely ask or tell, be asked or told, seek explanations and clarifications. Ideally such conversations should involve a mix of human and machine agents, able to collaborate in collective sensemaking activities with as few barriers as possible. Desirable capabilities include adding new knowledge, collaboratively building models, invoking specific services, and drawing inferences. As a step towards this goal, we collect evidence from a number of recent pilot studies including natural experiments (e.g. situation awareness in the context of organised protests) and synthetic experiments (e.g. human and machine agents collaborating in information seeking and spot reporting). We identify some principles and areas of future research for "conversational sensemaking".

  1. Hybrid reactors. [Fuel cycle

    SciTech Connect

    Moir, R.W.

    1980-09-09

    The rationale for hybrid fusion-fission reactors is the production of fissile fuel for fission reactors. A new class of reactor, the fission-suppressed hybrid promises unusually good safety features as well as the ability to support 25 light-water reactors of the same nuclear power rating, or even more high-conversion-ratio reactors such as the heavy-water type. One 4000-MW nuclear hybrid can produce 7200 kg of /sup 233/U per year. To obtain good economics, injector efficiency times plasma gain (eta/sub i/Q) should be greater than 2, the wall load should be greater than 1 MW.m/sup -2/, and the hybrid should cost less than 6 times the cost of a light-water reactor. Introduction rates for the fission-suppressed hybrid are usually rapid.

  2. Pashto Conversation Manual and Pashto Conversation Tapescript.

    ERIC Educational Resources Information Center

    Tegey, Habibullah; Robson, Barbara

    This conversation manual and tapescript are part of a set of materials that have been developed to teach oral and written Afghan Pashto to English speakers. In addition to the conversation manual and tapescript, the set consists of a beginning textbook, an intermediate textbook, a reader, and a set of taped lessons that correlate with the…

  3. Direct Conversion of Energy.

    ERIC Educational Resources Information Center

    Corliss, William R.

    This publication is one of a series of information booklets for the general public published by the United States Atomic Energy Commission. Direct energy conversion involves energy transformation without moving parts. The concepts of direct and dynamic energy conversion plus the laws governing energy conversion are investigated. Among the topics…

  4. Learning through Conversation.

    ERIC Educational Resources Information Center

    Kelly, Patricia R.; Klein, Adria F.; Pinnell, Gay Su

    1996-01-01

    Through teacher-child conversation, experts use oral language to help novices take on more complex tasks; and Reading Recovery children, who are obviously having difficulty with school-based learning, are especially in need of significant conversations with adults. Reading and writing processes are supported through conversation with Reading…

  5. Iterated multidimensional wave conversion

    SciTech Connect

    Brizard, A. J.; Tracy, E. R.; Johnston, D.; Kaufman, A. N.; Richardson, A. S.; Zobin, N.

    2011-12-23

    Mode conversion can occur repeatedly in a two-dimensional cavity (e.g., the poloidal cross section of an axisymmetric tokamak). We report on two novel concepts that allow for a complete and global visualization of the ray evolution under iterated conversions. First, iterated conversion is discussed in terms of ray-induced maps from the two-dimensional conversion surface to itself (which can be visualized in terms of three-dimensional rooms). Second, the two-dimensional conversion surface is shown to possess a symplectic structure derived from Dirac constraints associated with the two dispersion surfaces of the interacting waves.

  6. NGL data conversion system

    NASA Astrophysics Data System (ADS)

    Shoji, Masahiro; Horiuchi, Nobuyasu

    2005-06-01

    We are developing a NGL data conversion system for EPL, for LEEPL, and for EBDW, which is based on our established photomask data conversion system, PATACON PC-cluster. For EPL data conversion, it has SF division, Complementary division, Stitching, Proximity effect correction, Alignment mark insertion, EB stepper control data creation, and Mask inspection data creation. For LEEPL data conversion, it has Pattern checking, Complementary division, Stitching, Stress distortion correction, Alignment mark insertion, and Mask inspection data creation. For EB direct-writing data conversion, it has Proximity effect correction and Extraction of aperture pattern for cell projection exposure.

  7. Power conversion apparatus and method

    DOEpatents

    Su, Gui-Jia [Knoxville, TN

    2012-02-07

    A power conversion apparatus includes an interfacing circuit that enables a current source inverter to operate from a voltage energy storage device (voltage source), such as a battery, ultracapacitor or fuel cell. The interfacing circuit, also referred to as a voltage-to-current converter, transforms the voltage source into a current source that feeds a DC current to a current source inverter. The voltage-to-current converter also provides means for controlling and maintaining a constant DC bus current that supplies the current source inverter. The voltage-to-current converter also enables the current source inverter to charge the voltage energy storage device, such as during dynamic braking of a hybrid electric vehicle, without the need of reversing the direction of the DC bus current.

  8. Nuclear hybrid energy infrastructure

    SciTech Connect

    Agarwal, Vivek; Tawfik, Magdy S.

    2015-02-01

    The nuclear hybrid energy concept is becoming a reality for the US energy infrastructure where combinations of the various potential energy sources (nuclear, wind, solar, biomass, and so on) are integrated in a hybrid energy system. This paper focuses on challenges facing a hybrid system with a Small Modular Reactor at its core. The core of the paper will discuss efforts required to develop supervisory control center that collects data, supports decision-making, and serves as an information hub for supervisory control center. Such a center will also be a model for integrating future technologies and controls. In addition, advanced operations research, thermal cycle analysis, energy conversion analysis, control engineering, and human factors engineering will be part of the supervisory control center. Nuclear hybrid energy infrastructure would allow operators to optimize the cost of energy production by providing appropriate means of integrating different energy sources. The data needs to be stored, processed, analyzed, trended, and projected at right time to right operator to integrate different energy sources.

  9. An energy-harvesting scheme employing CuGaSe2 quantum dot-modified ZnO buffer layers for drastic conversion efficiency enhancement in inorganic-organic hybrid solar cells.

    PubMed

    Ho, Cherng-Rong; Tsai, Meng-Lin; Jhuo, Hung-Jun; Lien, Der-Hsien; Lin, Chin-An; Tsai, Shin-Hung; Wei, Tzu-Chiao; Huang, Kun-Ping; Chen, Show-An; He, Jr-Hau

    2013-07-21

    We demonstrated a promising route to enhance the performance of inverted organic photovoltaic (OPV) devices by the incorporation of CuGaSe2 (CGS) quantum dots (QDs) into the ZnO buffer layer of P3HT:PCBM-based devices. The modification of QDs provides better band alignment between the organic/cathode interface, improves ZnO crystal quality, and increases photon absorption, leading to more effective carrier transport/collection. By employing this energy-harvesting scheme, short-circuit current density, open-circuit voltage, and fill factor of the OPV device after CGS QD modification are improved by 9.43%, 7.02% and 6.31%, respectively, giving rise to a 23.8% enhancement in the power conversion efficiency.

  10. Analysis of Linear Conversion to Two Modes

    NASA Astrophysics Data System (ADS)

    Brizard, Alain J.; Jaun, Andre; Kaufman, Allan N.; Tracy, Eugene R.

    2003-10-01

    Recent experimental observations [1] and computer simulations [2] show that, in a tokamak plasma with multispecies ions, an incident magnetosonic wave converts either to an ion-hybrid Bernstein wave or to an ion-cyclotron wave, depending on the location of the conversion region in the poloidal cross section. We present a cold-plasma model of simultaneous conversion to these two modes, and obtain explicit expressions for transmission and conversion coefficients. Our approach is based on phase-space analysis of multiple conversion [3], in two or four phase-space dimensions (i.e., one or two spatial dimensions).Our ray-tracing algorithm [4], for detection of conversion and for treatment of ray-splitting due to conversion, will be applied to this process. 1.E Nelson-Melby, M Porkolab, P T Bonoli, Y Lin, A Mazurenko, S J Wukitch, Phys Rev Lett 90 (2003) 155004 2.E F Jaeger, L A Berry, J R Myra, D B Batchelor, E D'Azevedo, P T Bonoli, C K Phillips, D N Smithe, D A D'Ippolito, M D Carter, R J Dumont, J C Wright, R W Harvey, Phys Rev Lett 90 (2003) 195001 3. Y-M Liang, J J Morehead, D R Cook, T Fla, A N Kaufman, Physics Letters A193 (1994) 82 4. E R Tracy, A N Kaufman, A Jaun, Physics Letters A290 (2001) 309

  11. Biothermal modeling of post-cryoplasty atherosclerosis in restenotic patients.

    PubMed

    Men-Chi, H; Ravigururajan, T S

    2007-03-01

    Atherosclerosis is a leading cause of heart diseases and mortality around the world. Recently, cryoplasty has emerged as a potential alternative method to treat arterial atherosclerosis. Finite element heat transfer and mass transfer models are developed using ANSYS in this study. The model analyzes the heat transfer within the atherosclerotic plaque and arterial wall during the cryoplasty procedure. The model is useful in predicting the transient temperature through the diseased wall tissues. The results may be used to decide required treatment procedure to effectively freeze the plaque with minimal damage to the healthy arterial tissues. Finally, the model investigates the parameters that may effect temperature distribution within the tissues during the ablative procedure.

  12. Hybrid Vehicles

    DTIC Science & Technology

    2008-12-08

    hybrid electric vehicles typically contain potentially hazardous levels of electrical voltage or current. It is important to protect the operators...60740. ITOP 2-2-607(1)41 is used for tracked vehicles. 13 TOP 2-1-003 08 December 2008 Hybrid electric vehicles often employ much more

  13. Conversing with Computers

    NASA Technical Reports Server (NTRS)

    2004-01-01

    I/NET, Inc., is making the dream of natural human-computer conversation a practical reality. Through a combination of advanced artificial intelligence research and practical software design, I/NET has taken the complexity out of developing advanced, natural language interfaces. Conversational capabilities like pronoun resolution, anaphora and ellipsis processing, and dialog management that were once available only in the laboratory can now be brought to any application with any speech recognition system using I/NET s conversational engine middleware.

  14. LH wave absorption by mode conversion near ion cyclotron harmonics

    SciTech Connect

    Ko, K.; Bers, A.; Fuchs, V.

    1981-02-01

    Numerical studies of the dispersion relation near the lower-hybrid frequency in an inhomogeneous plasma (..delta.. n, ..delta.. T, ..delta.. B) show that portions of an incident lower-hybrid wave spectrum undergo successive but partial mode conversions to warm-plasma waves in the presence of ion cyclotron harmonics. Wave absorption beyond the first mode conversion occurs near an ion cyclotron harmonic where ion Landau damping is enhanced. A second-order dispersion relation numerically in good agreement with the full dispersion relation in the mode conversion region is derived using the condition par. delta D/par. delta k = 0. The mode conversion efficiency at each confluence is evaluated by solving the corresponding differential equation.

  15. Hybrid Organic/Inorganic Nanocomposites for Photovoltaic Cells

    PubMed Central

    Liu, Ruchuan

    2014-01-01

    Inorganic/organic hybrid solar cells have attracted a lot of interest due to their potential in combining the advantages of both components. To understand the key issues in association with photoinduced charge separation/transportation processes and to improve overall power conversion efficiency, various combinations with nanostructures of hybrid systems have been investigated. Here, we briefly review the structures of hybrid nanocomposites studied so far, and attempt to associate the power conversion efficiency with these nanostructures. Subsequently, we are then able to summarize the factors for optimizing the performance of inorganic/organic hybrid solar cells. PMID:28788591

  16. Conversation et Television (Conversation and Television)

    ERIC Educational Resources Information Center

    Vadde, Jean-Pierre

    1977-01-01

    Czechosovakian television has just presented a series of French Conversation Classes using audiovisual techniques and starring Czech actors and actresses. The setting of each dialog is in Czechoslovakia, and the situations are those in which a Czech would use French in his or her native land. (Text is in French.) (AMH)

  17. Conversations in Child Care

    ERIC Educational Resources Information Center

    Bardige, Betty; Segal, Marilyn

    2004-01-01

    In this article, Bardige and Segal discuss how teachers can help a toddler's language and literacy development through conversation. They suggest an array of tactics, from asking young children open-ended, intellectually challenging questions to going beyond the here and now when carrying on a conversation. Research has shown that the practice of…

  18. Energy conversion alternatives study

    NASA Technical Reports Server (NTRS)

    Shure, L. T.

    1979-01-01

    Comparison of coal based energy systems is given. Study identifies and compares various advanced energy conversion systems using coal or coal derived fuels for baselaoad electric power generation. Energy Conversion Alternatives Study (ECAS) reports provede government, industry, and general public with technically consistent basis for comparison of system's options of interest for fossilfired electric-utility application.

  19. The Art of Conversation.

    ERIC Educational Resources Information Center

    Ervin-Tripp, Susan

    1984-01-01

    Criticizes Dorval and Eckerman (included in this issue) for their findings' lack of generality due to the artificial nature of the conversational groups studied. Also both age changes in the ability to plan large conversational units and the functions of particular kinds of turns within these larger units are left unexplored. (CB)

  20. Recording Conversations in Schools.

    ERIC Educational Resources Information Center

    Gluckman, Ivan B.; Koerner, Thomas J., Jr.

    1988-01-01

    In general, because of varying federal and state legislation and a paucity of court decisions, the law governing the recording of conversations is in considerable flux. School personnel desiring to record conversations in school without the consent or knowledge of all parties involved must proceed with considerable caution. (Author)

  1. Content for Conversation Partners.

    ERIC Educational Resources Information Center

    Olson, Kathleen

    2002-01-01

    Suggests that a good strategy for helping English language learners to develop communicative competence in English is by pairing them with native English speakers. In such conversation programs, conversation partners should be provided with topics and activities that incorporate the goals, interests, and experiences of the learners. Recommends…

  2. The Conversation Class

    ERIC Educational Resources Information Center

    Jackson, Acy L.

    2012-01-01

    The conversation class occupies a unique place in the process of learning English as a second or foreign language. From the author's own experience in conducting special conversation classes with Persian-speaking adults, he has drawn up a number of simple but important guidelines, some of which he hopes may provide helpful suggestions for the…

  3. NUCLEAR CONVERSION APPARATUS

    DOEpatents

    Seaborg, G.T.

    1960-09-13

    A nuclear conversion apparatus is described which comprises a body of neutron moderator, tubes extending therethrough, uranium in the tubes, a fluid- circulating system associated with the tubes, a thorium-containing fluid coolant in the system and tubes, and means for withdrawing the fluid from the system and replacing it in the system whereby thorium conversion products may be recovered.

  4. Stellarator hybrids

    SciTech Connect

    Furth, H.P.; Ludescher, C.

    1984-08-01

    The present paper briefly reviews the subject of tokamak-stellarator and pinch-stellarator hybrids, and points to two interesting new possibilities: compact-torus-stellarators and mirror-stellarators.

  5. Survey of lower hybrid experiments

    SciTech Connect

    Porkolab, M.

    1983-05-01

    Recent developments in lower hybrid experiments are discussed. While a decade ago there were many small scale experiments which verified the fundamental aspects of wave propagation near and above the lower hybrid frequency, more recently the greatest interest has been in using lower hybrid waves to heat the plasma, and to drive currents in toroidal devices. While in the mid 70's lower hybrid heating experiments in tokamaks were carried out at the 100 to 200 kW level, in recent experiments powers up to 1 MW have been injected in the Alcator C tokamak at MIT. Also, while the earlier lower hybrid experiments concentrated on the ion heating regime (..omega.. approx. = ..omega../sub LH/), in the more recent experiments the electron heating regime (..omega.. greater than or equal to 2..omega../sub LH/) and the current drive regime (..omega.. > 2..omega../sub LH/) has been explored to a greater extent. The reason for this is that bulk ion heating near the mode conversion layer appears to be less reproducible and more difficult to achieve than electron heating (and concommitant collisional bulk ion heating). While the reason for this is not well understood, it is likely that as the wave frequency gets closer to the lower hybrid frequency the shorter wavelength waves may be more effectively absorbed and/or scattered near the plasma surface by nonlinear effects (parametric instabilities, low frequency fluctuations, etc.). Toroidal effects may further enhance such mechanisms.

  6. Postoperative conversion disorder.

    PubMed

    Afolabi, Kola; Ali, Sameer; Gahtan, Vivian; Gorji, Reza; Li, Fenghua; Nussmeier, Nancy A

    2016-05-01

    Conversion disorder is a psychiatric disorder in which psychological stress causes neurologic deficits. A 28-year-old female surgical patient had uneventful general anesthesia and emergence but developed conversion disorder 1 hour postoperatively. She reported difficulty speaking, right-hand numbness and weakness, and right-leg paralysis. Neurologic examination and imaging revealed no neuronal damage, herniation, hemorrhage, or stroke. The patient mentioned failing examinations the day before surgery and discontinuing her prescribed antidepressant medication, leading us to diagnose conversion disorder, with eventual confirmation by neuroimaging and follow-up examinations. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Solar Thermal Conversion

    SciTech Connect

    Kreith, F.; Meyer, R. T.

    1982-11-01

    The thermal conversion process of solar energy is based on well-known phenomena of heat transfer (Kreith 1976). In all thermal conversion processes, solar radiation is absorbed at the surface of a receiver, which contains or is in contact with flow passages through which a working fluid passes. As the receiver heats up, heat is transferred to the working fluid which may be air, water, oil, or a molten salt. The upper temperature that can be achieved in solar thermal conversion depends on the insolation, the degree to which the sunlight is concentrated, and the measures taken to reduce heat losses from the working fluid.

  8. Spectral Selectivity Applied To Hybrid Concentration Systems

    NASA Astrophysics Data System (ADS)

    Hamdy, M. A.; Luttmann, F.; Osborn, D. E.; Jacobson, M. R.; MacLeod, H. A.

    1985-12-01

    The efficiency of conversion of concentrated solar energy can be improved by separating the solar spectrum into portions matched to specific photoquantum processes and the balance used for photothermal conversion. The basic approaches of spectrally selective beam splitters are presented. A detailed simulation analysis using TRNSYS is developed for a spectrally selective hybrid photovoltaic/photothermal concentrating system. The analysis shows definite benefits to a spectrally selective approach.

  9. Responsive Teaching through Conversation

    ERIC Educational Resources Information Center

    Dozier, Cheryl; Garnett, Susan; Tabatabai, Simeen

    2011-01-01

    Conversations are the heart of responsive teaching. By talking with struggling learners, teachers can find out about their interests in order to design effective, personalized instruction; build relationships; work through complexities in teaching and learning; and celebrate successes.

  10. Photochemical Energy Conversion.

    ERIC Educational Resources Information Center

    Batschelet, William H.; George, Arnold

    1986-01-01

    Describes procedures for two demonstrations: (1) photochemical energy conversion using ferric oxalate actinometry and (2) liquification of gases using Freon 114. Safety precautions are given for both demonstrations, as are procedures and material specifications. (JM)

  11. Responsive Teaching through Conversation

    ERIC Educational Resources Information Center

    Dozier, Cheryl; Garnett, Susan; Tabatabai, Simeen

    2011-01-01

    Conversations are the heart of responsive teaching. By talking with struggling learners, teachers can find out about their interests in order to design effective, personalized instruction; build relationships; work through complexities in teaching and learning; and celebrate successes.

  12. Structured luminescence conversion layer

    DOEpatents

    Berben, Dirk; Antoniadis, Homer; Jermann, Frank; Krummacher, Benjamin Claus; Von Malm, Norwin; Zachau, Martin

    2012-12-11

    An apparatus device such as a light source is disclosed which has an OLED device and a structured luminescence conversion layer deposited on the substrate or transparent electrode of said OLED device and on the exterior of said OLED device. The structured luminescence conversion layer contains regions such as color-changing and non-color-changing regions with particular shapes arranged in a particular pattern.

  13. Bidirectional conversion between microwave and light via ferromagnetic magnons

    NASA Astrophysics Data System (ADS)

    Hisatomi, R.; Osada, A.; Tabuchi, Y.; Ishikawa, T.; Noguchi, A.; Yamazaki, R.; Usami, K.; Nakamura, Y.

    2016-05-01

    Coherent conversion of microwave and optical photons in the single quantum level can significantly expand our ability to process signals in various fields. Efficient up-conversion of a feeble signal in the microwave domain to the optical domain will lead to quantum-noise-limited microwave amplifiers. Coherent exchange between optical photons and microwave photons will also be a stepping stone to realize long-distance quantum communication. Here we demonstrate bidirectional and coherent conversion between microwave and light using collective spin excitations in a ferromagnet. The converter consists of two harmonic oscillator modes, a microwave cavity mode and a magnetostatic mode called the Kittel mode, where microwave photons and magnons in the respective modes are strongly coupled and hybridized. An itinerant microwave field and a traveling optical field can be coupled through the hybrid system, where the microwave field is coupled to the hybrid system through the cavity mode, while the optical field addresses the hybrid system through the Kittel mode via Faraday and inverse Faraday effects. The conversion efficiency is theoretically analyzed and experimentally evaluated. The possible schemes for improving the efficiency are also discussed.

  14. Conversational flow promotes solidarity.

    PubMed

    Koudenburg, Namkje; Postmes, Tom; Gordijn, Ernestine H

    2013-01-01

    Social interaction is fundamental to the development of various aspects of "we-ness". Previous research has focused on the role the content of interaction plays in establishing feelings of unity, belongingness and shared reality (a cluster of variables referred to as solidarity here). The present paper is less concerned with content, but focuses on the form of social interaction. We propose that the degree to which conversations flow smoothly or not is, of itself, a cue to solidarity. We test this hypothesis in samples of unacquainted and acquainted dyads who communicate via headsets. Conversational flow is disrupted by introducing a delay in the auditory feedback (vs. no delay). Results of three studies show that smoothly coordinated conversations (compared with disrupted conversations and a control condition) increase feelings of belonging and perceptions of group entitativity, independently of conversation content. These effects are driven by the subjective experience of conversational flow. Our data suggest that this process occurs largely beyond individuals' control. We conclude that the form of social interaction is a powerful cue for inferring group solidarity. Implications for the impact of modern communication technology on developing a shared social identity are discussed.

  15. Microbatteries for self-sustained hybrid micropower supplies

    NASA Astrophysics Data System (ADS)

    Harb, John N.; LaFollette, Rodney M.; Selfridge, Richard H.; Howell, Larry L.

    This paper describes the characteristics of microbatteries suitable for use in a hybrid micropower supply for powering autonomous MEMS and other microsystems. The hybrid power supply includes an energy conversion device, microscopic batteries for energy storage, and control/interface circuitry. Comparison of the hybrid approach with single power sources (either a battery or energy conversion device alone) shows that it offers several potential advantages including reduced size, increased flexibility, long lifetime and increased reliability. Such an approach is well suited to the expected duty cycles of remote microsensors. Realization of the advantages of a hybrid system depends on the availability of a battery with the required characteristics. Initial experimental results demonstrate the feasibility of fabricating microbatteries with the proper characteristics and the use of these batteries as part of a hybrid micropower supply. It is anticipated that hybrid micropower supplies with suitable microbatteries will play a critical role in the successful implementation of a wide variety of autonomous microsystems.

  16. Approaches for biological and biomimetic energy conversion

    PubMed Central

    LaVan, David A.; Cha, Jennifer N.

    2006-01-01

    This article highlights areas of research at the interface of nanotechnology, the physical sciences, and biology that are related to energy conversion: specifically, those related to photovoltaic applications. Although much ongoing work is seeking to understand basic processes of photosynthesis and chemical conversion, such as light harvesting, electron transfer, and ion transport, application of this knowledge to the development of fully synthetic and/or hybrid devices is still in its infancy. To develop systems that produce energy in an efficient manner, it is important both to understand the biological mechanisms of energy flow for optimization of primary structure and to appreciate the roles of architecture and assembly. Whether devices are completely synthetic and mimic biological processes or devices use natural biomolecules, much of the research for future power systems will happen at the intersection of disciplines. PMID:16567648

  17. Development and Exploration of Nanoparticle Decorated Carbon Supports (Graphene and Graphene Oxide) for Energy Collection, Storage, and Conversion

    DTIC Science & Technology

    2012-12-17

    hybrid films as an alternative to organic-based photoactive materials in flexible photodetectors and solar cells . Figure 3. Solution...a wide range of metal nanoparticle-decorated (Pt, Au, Ag, Pt/Ru) graphene oxide (GO) hybrids as well as inorganic particle-graphene ( TiO2 /PbSe/G... hybrids . These hybrids were then evaluated for their performance in energy conversion devices and two examples were chosen, namely stacked fuel cells

  18. Extremely compact slanted waveguide hybrid plasmonic polarization rotator

    NASA Astrophysics Data System (ADS)

    Nikoufard, Mahmoud; Hatami, Mohsen

    2017-01-01

    In this study, we proposed a novel slanted waveguide hybrid plasmonic polarization splitter based on mode evolution at 1.55 μm wavelength on silicon-on-insulator technology. The TM polarization is rotated to the TE polarization with a conversion length of 370 nm, polarization conversion efficiency of 85% and polarization extinction ratio larger than 18 dB.

  19. Clients as conversational agents.

    PubMed

    Massfeller, Helen F; Strong, Tom

    2012-08-01

    Conversational agency is our invented term that orients us to ways in which clients participate in therapeutic dialogues. In this study we examined how clients' conversational correctives and initiatives influenced collaborative therapeutic consultations. Thirty-five single-session lifestyle consultations were videotaped in which adult clients volunteered to discuss concerns of non-clinical severity with a counselor. We discursively microanalyzed excerpts where clients initiated topic shifts or corrected counselor misunderstandings and how counselors responded to them. Clients were actively involved in co-managing conversational developments during the consultations. They influenced the content and course of the conversations with the counselors by correcting, interrupting, or speaking from positions contrary or unrelated to those of the counselors. Clients observably influenced the conversational agenda through their correctives and initiatives if counselors were responsive during face-to-face consultations. Clinicians should demonstrate increased sensitivity and relational responsivity by intentionally engaging with clients' agentive contributions to consultative dialogues. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  20. Isomolybdate conversion coatings

    NASA Technical Reports Server (NTRS)

    Minevski, Zoran (Inventor); Maxey, Jason (Inventor); Nelson, Carl (Inventor); Eylem, Cahit (Inventor)

    2002-01-01

    A conversion coating solution and process forms a stable and corrosion-resistant layer on metal substrates or layers or, more preferably, on a boehmite layer or other base conversion coating. The conversion coating process involves contacting the substrate, layer or coating with an aqueous alkali metal isomolybdate solution in order to convert the surface of the substrate, layer or coating to a stable conversion coating. The aqueous alkali metal molybdates are selected from sodium molybdate (Na.sub.2 MoO.sub.4), lithium molybdate (Li.sub.2 MoO.sub.4), potassium molybdate (K.sub.2 MoO.sub.4), or combinations thereof, with the most preferred alkali metal molybdate being sodium molybdate. The concentration of alkali metal molybdates in the solution is preferably less than 5% by weight. In addition to the alkali metal molybdates, the conversion coating solution may include alkaline metal passivators selected from lithium nitrate (LiNO.sub.3), sodium nitrate (NaNO.sub.3), ammonia nitrate (NH.sub.4 NO.sub.3), and combinations thereof; lithium chloride, potassium hexafluorozirconate (K.sub.2 ZrF.sub.6) or potassium hexafluorotitanate (K.sub.2 TiF.sub.6).

  1. Laser energy conversion

    NASA Technical Reports Server (NTRS)

    Jalufka, N. W.

    1989-01-01

    The conversion of laser energy to other, more useful, forms is an important element of any space power transmission system employing lasers. In general the user, at the receiving sight, will require the energy in a form other than laser radiation. In particular, conversion to rocket power and electricity are considered to be two major areas where one must consider various conversion techniques. Three systems (photovoltaic cells, MHD generators, and gas turbines) have been identified as the laser-to-electricity conversion systems that appear to meet most of the criteria for a space-based system. The laser thruster also shows considerable promise as a space propulsion system. At this time one cannot predict which of the three laser-to-electric converters will be best suited to particular mission needs. All three systems have some particular advantages, as well as disadvantages. It would be prudent to continue research on all three systems, as well as the laser rocket thruster. Research on novel energy conversion systems, such as the optical rectenna and the reverse free-electron laser, should continue due to their potential for high payoff.

  2. Laser energy conversion

    NASA Astrophysics Data System (ADS)

    Jalufka, N. W.

    1989-07-01

    The conversion of laser energy to other, more useful, forms is an important element of any space power transmission system employing lasers. In general the user, at the receiving sight, will require the energy in a form other than laser radiation. In particular, conversion to rocket power and electricity are considered to be two major areas where one must consider various conversion techniques. Three systems (photovoltaic cells, MHD generators, and gas turbines) have been identified as the laser-to-electricity conversion systems that appear to meet most of the criteria for a space-based system. The laser thruster also shows considerable promise as a space propulsion system. At this time one cannot predict which of the three laser-to-electric converters will be best suited to particular mission needs. All three systems have some particular advantages, as well as disadvantages. It would be prudent to continue research on all three systems, as well as the laser rocket thruster. Research on novel energy conversion systems, such as the optical rectenna and the reverse free-electron laser, should continue due to their potential for high payoff.

  3. Direct conversion technology

    SciTech Connect

    Massier, P.F.; Back, L.H.; Ryan, M.A.; Fabris, G.

    1992-01-07

    The overall objective of the Direct Conversion Technology task is to develop an experimentally verified technology base for promising direct conversion systems that have potential application for energy conservation in the end-use sectors. This report contains progress of research on the Alkali Metal Thermal-to-Electric Converter (AMTEC) and on the Two-Phase Liquid-Metal MHD Electrical Generator (LMMHD) for the period January 1, 1991 through December 31, 1991. Research on AMTEC and on LMMHD was initiated during October 1987. Reports prepared on previous occasions (Refs. 1--5) contain descriptive and performance discussions of the following direct conversion concepts: thermoelectric, pyroelectric, thermionic, thermophotovoltaic, thermoacoustic, thermomagnetic, thermoelastic (Nitionol heat engine); and also, more complete descriptive discussions of AMTEC and LMMHD systems.

  4. Frequency conversion system

    NASA Technical Reports Server (NTRS)

    Sanders, Steven (Inventor); Waarts, Robert G. (Inventor)

    2001-01-01

    A frequency conversion system comprises first and second gain sources providing first and second frequency radiation outputs where the second gain source receives as input the output of the first gain source and, further, the second gain source comprises a Raman or Brillouin gain fiber for wave shifting a portion of the radiation of the first frequency output into second frequency radiation output to provided a combined output of first and second frequencies. Powers are gain enhanced by the addition of a rare earth amplifier or oscillator, or a Raman/Brillouin amplifier or oscillator between the high power source and the NFM device. Further, polarization conversion using Raman or Brillouin wavelength shifting is provided to optimize frequency conversion efficiency in the NFM device.

  5. Overview of coal conversion

    SciTech Connect

    Clark, B.R.

    1981-03-27

    The structure of coal and the processes of coal gasification and coal liquefaction are reviewed. While coal conversion technology is not likely to provide a significant amount of synthetic fuel within the next several years, there is a clear interest both in government and private sectors in the development of this technology to hedge against ever-diminishing petroleum supplies, especially from foreign sources. It is evident from this rather cursory survey that there is some old technology that is highly reliable; new technology is being developed but is not ready for commercialization at the present state of development. The area of coal conversion is ripe for exploration both on the applied and basic research levels. A great deal more must be understood about the reactions of coal, the reactions of coal products, and the physics and chemistry involved in the various stages of coal conversion processes in order to make this technology economically viable.

  6. Direct conversion technology

    NASA Technical Reports Server (NTRS)

    Massier, Paul F.; Bankston, C. P.; Williams, R.; Underwood, M.; Jeffries-Nakamura, B.; Fabris, G.

    1989-01-01

    The overall objective of the Direct Conversion Technology task is to develop an experimentally verified technology base for promising direct conversion systems that have potential application for energy conservation in the end-use sectors. This report contains progress of research on the Alkali Metal Thermal-to-Electric Converter (AMTEC), and on the Two-Phase Liquid-Metal Magnetohydrodynamic Electrical Generator (LMMHD) for the period January 1, 1989 through December 31, 1989. Research on these concepts was initiated during October 1987. Reports prepared on previous occasions contain discussions on the following other direct conversion concepts: thermoelectric, pyroelectric, thermionic, thermophotovoltaic, thermoacoustic, thermomagnetic, thermoelastic (nitinol heat engines); and also, more complete discussions of AMTEC and LMMHD systems.

  7. Digital optical conversion module

    DOEpatents

    Kotter, Dale K.; Rankin, Richard A.

    1991-02-26

    A digital optical conversion module used to convert an analog signal to a computer compatible digital signal including a voltage-to-frequency converter, frequency offset response circuitry, and an electrical-to-optical converter. Also used in conjunction with the digital optical conversion module is an optical link and an interface at the computer for converting the optical signal back to an electrical signal. Suitable for use in hostile environments having high levels of electromagnetic interference, the conversion module retains high resolution of the analog signal while eliminating the potential for errors due to noise and interference. The module can be used to link analog output scientific equipment such as an electrometer used with a mass spectrometer to a computer.

  8. Digital optical conversion module

    DOEpatents

    Kotter, D.K.; Rankin, R.A.

    1988-07-19

    A digital optical conversion module used to convert an analog signal to a computer compatible digital signal including a voltage-to-frequency converter, frequency offset response circuitry, and an electrical-to-optical converter. Also used in conjunction with the digital optical conversion module is an optical link and an interface at the computer for converting the optical signal back to an electrical signal. Suitable for use in hostile environments having high levels of electromagnetic interference, the conversion module retains high resolution of the analog signal while eliminating the potential for errors due to noise and interference. The module can be used to link analog output scientific equipment such as an electrometer used with a mass spectrometer to a computer. 2 figs.

  9. Predictability of Conversation Partners

    NASA Astrophysics Data System (ADS)

    Takaguchi, Taro; Nakamura, Mitsuhiro; Sato, Nobuo; Yano, Kazuo; Masuda, Naoki

    2011-08-01

    Recent developments in sensing technologies have enabled us to examine the nature of human social behavior in greater detail. By applying an information-theoretic method to the spatiotemporal data of cell-phone locations, [C. Song , ScienceSCIEAS0036-8075 327, 1018 (2010)] found that human mobility patterns are remarkably predictable. Inspired by their work, we address a similar predictability question in a different kind of human social activity: conversation events. The predictability in the sequence of one’s conversation partners is defined as the degree to which one’s next conversation partner can be predicted given the current partner. We quantify this predictability by using the mutual information. We examine the predictability of conversation events for each individual using the longitudinal data of face-to-face interactions collected from two company offices in Japan. Each subject wears a name tag equipped with an infrared sensor node, and conversation events are marked when signals are exchanged between sensor nodes in close proximity. We find that the conversation events are predictable to a certain extent; knowing the current partner decreases the uncertainty about the next partner by 28.4% on average. Much of the predictability is explained by long-tailed distributions of interevent intervals. However, a predictability also exists in the data, apart from the contribution of their long-tailed nature. In addition, an individual’s predictability is correlated with the position of the individual in the static social network derived from the data. Individuals confined in a community—in the sense of an abundance of surrounding triangles—tend to have low predictability, and those bridging different communities tend to have high predictability.

  10. Hybrid Molten Salt Reactor (HMSR) System Study

    SciTech Connect

    Woolley, Robert D; Miller, Laurence F

    2014-04-01

    Can the hybrid system combination of (1) a critical fission Molten Salt Reactor (MSR) having a thermal spectrum and a high Conversion Ratio (CR) with (2) an external source of high energy neutrons provide an attractive solution to the world's expanding demand for energy? The present study indicates the answer is an emphatic yes.

  11. ADEPT: Efficient Power Conversion

    SciTech Connect

    2011-01-01

    ADEPT Project: In today’s increasingly electrified world, power conversion—the process of converting electricity between different currents, voltage levels, and frequencies—forms a vital link between the electronic devices we use every day and the sources of power required to run them. The 14 projects that make up ARPA-E’s ADEPT Project, short for “Agile Delivery of Electrical Power Technology,” are paving the way for more energy efficient power conversion and advancing the basic building blocks of power conversion: circuits, transistors, inductors, transformers, and capacitors.

  12. Power conversion technologies

    SciTech Connect

    Haigh, R E

    1998-01-01

    The Power Conservation Technologies thrust area supports initiatives that enhance the core competencies of the Lawrence Livermore National Laboratory (LLNL) Engineering Directorate in the area of solid-state power electronics. Through partnerships with LLNL programs, projects focus on the development of enabling technologies for existing and emerging programs that have unique power conversion requirements. This year, a multi-disciplinary effort was supported which demonstrated solid-state, high voltage generation by using a dense, monolithic photovoltaic array. This effort builds upon Engineering's strengths in the core technology areas of power conversion, photonics, and microtechnologies.

  13. Direct Conversion Technology

    SciTech Connect

    Back, L.H.; Fabris, G.; Ryan, M.A.

    1992-07-01

    The overall objective of the Direct Conversion Technology task is to develop an experimentally verified technology base for promising direct conversion systems that have potential application for energy conservation in the end-use sectors. Initially, two systems were selected for exploratory research and advanced development. These are Alkali Metal Thermal-to-Electric Converter (AMTEC) and Two-Phase Liquid Metal MD Generator (LMMHD). This report describes progress that has been made during the first six months of 1992 on research activities associated with these two systems. (GHH)

  14. Planetary image conversion task

    NASA Technical Reports Server (NTRS)

    Martin, M. D.; Stanley, C. L.; Laughlin, G.

    1985-01-01

    The Planetary Image Conversion Task group processed 12,500 magnetic tapes containing raw imaging data from JPL planetary missions and produced an image data base in consistent format on 1200 fully packed 6250-bpi tapes. The output tapes will remain at JPL. A copy of the entire tape set was delivered to US Geological Survey, Flagstaff, Ariz. A secondary task converted computer datalogs, which had been stored in project specific MARK IV File Management System data types and structures, to flat-file, text format that is processable on any modern computer system. The conversion processing took place at JPL's Image Processing Laboratory on an IBM 370-158 with existing software modified slightly to meet the needs of the conversion task. More than 99% of the original digital image data was successfully recovered by the conversion task. However, processing data tapes recorded before 1975 was destructive. This discovery is of critical importance to facilities responsible for maintaining digital archives since normal periodic random sampling techniques would be unlikely to detect this phenomenon, and entire data sets could be wiped out in the act of generating seemingly positive sampling results. Reccomended follow-on activities are also included.

  15. Clinical Linguistics: Conversational Reflections

    ERIC Educational Resources Information Center

    Crystal, David

    2013-01-01

    This is a report of the main points I made in an informal "conversation" with Paul Fletcher and the audience at the 14th ICPLA conference in Cork. The observations arose randomly, as part of an unstructured 1-h Q&A, so they do not provide a systematic account of the subject, but simply reflect the issues which were raised by the conference…

  16. Stories in Conversation.

    ERIC Educational Resources Information Center

    Hofer, Roberta Senner

    Although conversational stories within one individual's corpus share the same structure, they have features that set them apart from one another. Based on the stories' general characteristics and the way they function in ongoing talk, they can be identified as: (1) durable personal experience narratives (PENs), which are often repeated during the…

  17. Evaluating Energy Conversion Efficiency

    NASA Technical Reports Server (NTRS)

    Byvik, C. E.; Smith, B. T.; Buoncristiani, A. M.

    1983-01-01

    Devices that convert solar radiation directly into storable chemical or electrical energy, have characteristic energy absorption spectrum; specifically, each of these devices has energy threshold. The conversion efficiency of generalized system that emcompasses all threshold devices is analyzed, resulting in family of curves for devices of various threshold energies operating at different temperatures.

  18. A Conversation about Observation

    NASA Technical Reports Server (NTRS)

    Mather, John C.; Mao, Minnie Yuan

    2012-01-01

    In the spirit of the Lindau Meeting, we present a dialogue between a Nobel laureate and a young researcher. This interchange started online, where it continues to unfold. Here is a digest of this conversation, which has developed across time and space.

  19. Conversations and Collaborations

    ERIC Educational Resources Information Center

    Korpan, Cynthia

    2010-01-01

    This paper looks at how a series of conversations contributed to the development of a newly formed role at the University of Victoria--Teaching Assistant Consultants (TACs). TACs act as departmental mentors for teaching assistants (TAs) in their respective departments, charged with providing support in the form of discipline-specific workshops…

  20. Clinical Linguistics: Conversational Reflections

    ERIC Educational Resources Information Center

    Crystal, David

    2013-01-01

    This is a report of the main points I made in an informal "conversation" with Paul Fletcher and the audience at the 14th ICPLA conference in Cork. The observations arose randomly, as part of an unstructured 1-h Q&A, so they do not provide a systematic account of the subject, but simply reflect the issues which were raised by the conference…

  1. Ocean thermal energy conversion

    SciTech Connect

    Avery, W.H.

    1983-03-17

    A brief explanation of the Ocean Thermal Energy Conversion (OTEC) concept and an estimate of the amount of energy that can be produced from the ocean resource without introducing environmental concerns are presented. Use of the OTEC system to generate electric power and products which can replace fossil fuels is shown. The OTEC program status and its prospects for the future are discussed.

  2. Electromechanical Energy Conversion.

    ERIC Educational Resources Information Center

    LePage, Wilbur R.

    This programed text on electromechanical energy conversion (motors and generators) was developed under contract with the U.S. Office of Education as Number 12 in a series of materials for use in an electrical engineering sequence. It is intended to be used in conjunction with other materials and with other short texts in the series. (DH)

  3. Evaluating Energy Conversion Efficiency

    NASA Technical Reports Server (NTRS)

    Byvik, C. E.; Smith, B. T.; Buoncristiani, A. M.

    1983-01-01

    Devices that convert solar radiation directly into storable chemical or electrical energy, have characteristic energy absorption spectrum; specifically, each of these devices has energy threshold. The conversion efficiency of generalized system that emcompasses all threshold devices is analyzed, resulting in family of curves for devices of various threshold energies operating at different temperatures.

  4. Conversational English Program, 2.

    ERIC Educational Resources Information Center

    Instituto de Idiomas Yazigi, Sao Paulo (Brazil). Centro de Linguistica Aplicada.

    This second book of a conversational English program for adults contains an introductory section in Portuguese and exercises in English. The text centers around an English-speaking family from the United States that goes to live in Brazil. It contains color photographs with captions followed by exercises. The exercises are in English and involve…

  5. Mechanochemical Energy Conversion

    ERIC Educational Resources Information Center

    Pines, E.; And Others

    1973-01-01

    Summarizes the thermodynamics of macromolecular systems, including theories and experiments of cyclic energy conversion with rubber and collagen as working substances. Indicates that an early introduction into the concept of chemical potential and solution thermodynamics is made possible through the study of the cyclic processes. (CC)

  6. Conversational English Program, 1.

    ERIC Educational Resources Information Center

    Instituto de Idiomas Yazigi, Sao Paulo (Brazil). Centro de Linguistica Aplicada.

    This first book of a conversational English program for adults contains an introductory section in Portuguese and exercises in English. The text centers around an English-speaking family from the United States that goes to live in Brazil. It contains color photographs with captions followed by exercises. The exercises are in English and involve…

  7. Mechanochemical Energy Conversion

    ERIC Educational Resources Information Center

    Pines, E.; And Others

    1973-01-01

    Summarizes the thermodynamics of macromolecular systems, including theories and experiments of cyclic energy conversion with rubber and collagen as working substances. Indicates that an early introduction into the concept of chemical potential and solution thermodynamics is made possible through the study of the cyclic processes. (CC)

  8. Leadership is a conversation.

    PubMed

    Groysberg, Boris; Slind, Michael

    2012-06-01

    Globalization and new technologies have sharply reduced the efficacy of command-and-control management and its accompanying forms of corporate communication. In the course of a recent research project, the authors concluded that by talking with employees, rather than simply issuing orders, leaders can promote operational flexibility, employee engagement, and tight strategic alignment. Groysberg and Slind have identified four elements of organizational conversation that reflect the essential attributes of interpersonal conversation: intimacy, interactivity, inclusion, and intentionality. Intimacy shifts the focus from a top-down distribution of information to a bottom-up exchange of ideas. Organizational conversation is less corporate in tone and more casual. And it's less about issuing and taking orders than about asking and answering questions. Interactivity entails shunning the simplicity of monologue and embracing the unpredictable vitality of dialogue. Traditional one-way media-print and broadcast, in particular-give way to social media buttressed by social thinking. Inclusion turns employees into full-fledged conversation partners, entitling them to provide their own ideas, often on company channels. They can create content and act as brand ambassadors, thought leaders, and storytellers. Intentionality enables leaders and employees to derive strategically relevant action from the push and pull of discussion and debate.

  9. Conversations on ecology IV

    USGS Publications Warehouse

    Leopold, Luna Bergere

    1963-01-01

    The conversations on ecology have mentioned the pesticide problem, and in such discussion it is easy to lose sight of the basic philosophic view which is an undercurrent in Miss Carson's book. I should like to expand on that philosophic premise and examine some of its implications for planning vegetation management measures as well as other measures for resource development.

  10. Conversion or New Building?

    ERIC Educational Resources Information Center

    Berkeley, Phil

    1970-01-01

    Examined first is "the overall problem of housing a TV studio complex to see what particular sorts of buildings are required and how they must be related," and then considered are "the relative merits and particular problems of new studio building or a conversion." (LS)

  11. Solar energy conversion.

    SciTech Connect

    Crabtree, G. W.; Lewis, N. S.

    2008-03-01

    If solar energy is to become a practical alternative to fossil fuels, we must have efficient ways to convert photons into electricity, fuel, and heat. The need for better conversion technologies is a driving force behind many recent developments in biology, materials, and especially nanoscience. The Sun has the enormous untapped potential to supply our growing energy needs. The barrier to greater use of the solar resource is its high cost relative to the cost of fossil fuels, although the disparity will decrease with the rising prices of fossil fuels and the rising costs of mitigating their impact on the environment and climate. The cost of solar energy is directly related to the low conversion efficiency, the modest energy density of solar radiation, and the costly materials currently required. The development of materials and methods to improve solar energy conversion is primarily a scientific challenge: Breakthroughs in fundamental understanding ought to enable marked progress. There is plenty of room for improvement, since photovoltaic conversion efficiencies for inexpensive organic and dye-sensitized solar cells are currently about 10% or less, the conversion efficiency of photosynthesis is less than 1%, and the best solar thermal efficiency is 30%. The theoretical limits suggest that we can do much better. Solar conversion is a young science. Its major growth began in the 1970s, spurred by the oil crisis that highlighted the pervasive importance of energy to our personal, social, economic, and political lives. In contrast, fossil-fuel science has developed over more than 250 years, stimulated by the Industrial Revolution and the promise of abundant fossil fuels. The science of thermodynamics, for example, is intimately intertwined with the development of the steam engine. The Carnot cycle, the mechanical equivalent of heat, and entropy all played starring roles in the development of thermodynamics and the technology of heat engines. Solar-energy science faces

  12. Fabrication of biomolecule copolymer hybrid nanovesicles as energy conversion systems

    NASA Astrophysics Data System (ADS)

    Ho, Dean; Chu, Benjamin; Lee, Hyeseung; Brooks, Evan K.; Kuo, Karen; Montemagno, Carlo D.

    2005-12-01

    This work demonstrates the integration of the energy-transducing proteins bacteriorhodopsin (BR) from Halobacterium halobium and cytochrome c oxidase (COX) from Rhodobacter sphaeroides into block copolymeric vesicles towards the demonstration of coupled protein functionality. An ABA triblock copolymer-based biomimetic membrane possessing UV-curable acrylate endgroups was synthesized to serve as a robust matrix for protein reconstitution. BR-functionalized polymers were shown to generate light-driven transmembrane pH gradients while pH gradient-induced electron release was observed from COX-functionalized polymers. Cooperative behaviour observed from composite membrane functionalized by both proteins revealed the generation of microamp-range currents with no applied voltage. As such, it has been shown that the fruition of technologies based upon bio-functionalizing abiotic materials may contribute to the realization of high power density devices inspired by nature.

  13. Wind energy conversion system

    DOEpatents

    Longrigg, Paul

    1987-01-01

    The wind energy conversion system includes a wind machine having a propeller connected to a generator of electric power, the propeller rotating the generator in response to force of an incident wind. The generator converts the power of the wind to electric power for use by an electric load. Circuitry for varying the duty factor of the generator output power is connected between the generator and the load to thereby alter a loading of the generator and the propeller by the electric load. Wind speed is sensed electro-optically to provide data of wind speed upwind of the propeller, to thereby permit tip speed ratio circuitry to operate the power control circuitry and thereby optimize the tip speed ratio by varying the loading of the propeller. Accordingly, the efficiency of the wind energy conversion system is maximized.

  14. Frequency conversion system

    NASA Technical Reports Server (NTRS)

    Sanders, Steven (Inventor); Lang, Robert J. (Inventor)

    2001-01-01

    Laser diode pumped mid-IR wavelength sources include at least one high power, near-IR wavelength, injection and/or sources wherein one or both of such sources may be tunable providing a pump wave output beam to a quasi-phase matched (QPM) nonlinear frequency mixing (NFM) device. The NFM device may be a difference frequency mixing (DFM) device or an optical parametric oscillation (OPO) device. Wavelength tuning of at least one of the sources advantageously provides the ability for optimizing pump or injection wavelengths to match the QPM properties of the NFM device enabling a broad range of mid-IR wavelength selectivity. Also, pump powers are gain enhanced by the addition of a rare earth amplifier or oscillator, or a Raman/Brillouin amplifier or oscillator between the high power source and the NFM device. Further, polarization conversion using Raman or Brillouin wavelength shifting is provided to optimize frequency conversion efficiency in the NFM device.

  15. Clinical linguistics: conversational reflections.

    PubMed

    Crystal, David

    2013-04-01

    This is a report of the main points I made in an informal "conversation" with Paul Fletcher and the audience at the 14th ICPLA conference in Cork. The observations arose randomly, as part of an unstructured 1-h Q&A, so they do not provide a systematic account of the subject, but simply reflect the issues which were raised by the conference participants during that time.

  16. Advanced Thermal Conversion Systems

    DTIC Science & Technology

    2015-03-18

    BAA09-31 3  Figure 1. (a) Energy diagram of the PETE process. Photo -excitation leads to enhanced...photovoltaic cells at 3000x concentration (~38%). As shown in Fig. 2(b), the highest conversion efficiencies are obtained by using photo -cathodes...p-type 4H-SiC (left) and polycrystalline n-type 3C-SiC (right). The fabrication process for p-type devices used bulk p- doped 4H-SiC wafers from

  17. Session: Energy Conversion

    SciTech Connect

    Robertson, David; LaSala, Raymond J.; Kukacka, Lawrence E.; Bliem, Carl J.; Premuzic, Eugene T.; Weare, John H.

    1992-01-01

    This session at the Geothermal Energy Program Review X: Geothermal Energy and the Utility Market consisted of five presentations: ''Hydrothermal Energy Conversion Technology'' by David Robertson and Raymond J. LaSala; ''Materials for Geothermal Production'' by Lawrence E. Kukacka; ''Supersaturated Turbine Expansions for Binary Geothermal Power Plants'' by Carl J. Bliem; ''Geothermal Waster Treatment Biotechnology: Progress and Advantages to the Utilities'' by Eugen T. Premuzic; and ''Geothermal Brine Chemistry Modeling Program'' by John H. Weare.

  18. Persuasion Detection in Conversation

    DTIC Science & Technology

    2010-03-01

    is the first step in developing machine learning systems that can automatically detect persuasion in conversations. This corpus was developed from...requires some form of persuasion. Based on this research, it may be possible to construct a machine learning system that can automatically detect...specific markers, can these markers be learned and identified by annotators? Our research attempted to answer all of these questions by annotating a

  19. Direct conversion technology

    NASA Technical Reports Server (NTRS)

    Massier, P. F.; Bankston, C. P.; Fabris, G.; Kirol, L. D.

    1988-01-01

    The overall objective of the Direct Conversion Technology task is to develop an experimentally verified technology base for promising direct thermal-to-electric energy conversion systems that have potential application for energy conservation in the end-use sectors. This report contains progress of research on the Alkali Metal Thermal-to-Electric Converter (AMTEC), and on the Two-Phase Liquid-Metal MHD Electrical Generator (LMMHD) for the period January 1988 through December 1988. Research on these concepts was initiated during October 1987. In addition, status reviews and assessments are presented for thermomagnetic converter concepts and for thermoelastic converters (Nitinol heat engines). Reports prepared on previous occasions contain discussions on the following other direct conversion concepts: thermoelectric, pyroelectric, thermionic thermophotovoltaic and thermoacoustic; and also, more complete discussions of AMTEC and LMMHD systems. A tabulated summary of the various systems which have been reviewed thus far has been prepared. Some of the important technical research needs are listed and a schematic of each system is shown.

  20. Natural gas conversion process

    SciTech Connect

    Not Available

    1992-01-01

    The experimental apparatus was dismantled and transferred to a laboratory space provided by Lawrence Berkeley Laboratory (LBL) which is already equipped with a high-ventilation fume hood. This will enable us to make tests at higher gas flow rates in a safe environment. Three papers presented at the ACS meeting in San Francisco (Symposium on Natural Gas Upgrading II) April 5--10, 1992 show that the goal of direct catalytic conversion of Methane into heavier Hydrocarbons in a reducing atmosphere is actively pursued in three other different laboratories. There are similarities in their general concept with our own approach, but the temperature range of the experiments reported in these recent papers is much lower and this leads to uneconomic conversion rates. This illustrates the advantages of Methane activation by a Hydrogen plasma to reach commercial conversion rates. A preliminary process flow diagram was established for the Integrated Process, which was outlined in the previous Quarterly Report. The flow diagram also includes all the required auxiliary facilities for product separation and recycle of the unconverted feed as well as for the preparation and compression of the Syngas by-product.

  1. Direct conversion technology

    NASA Astrophysics Data System (ADS)

    Massier, P. F.; Bankston, C. P.; Fabris, G.; Kirol, L. D.

    1988-12-01

    The overall objective of the Direct Conversion Technology task is to develop an experimentally verified technology base for promising direct thermal-to-electric energy conversion systems that have potential application for energy conservation in the end-use sectors. This report contains progress of research on the Alkali Metal Thermal-to-Electric Converter (AMTEC), and on the Two-Phase Liquid-Metal MHD Electrical Generator (LMMHD) for the period January 1988 through December 1988. Research on these concepts was initiated during October 1987. In addition, status reviews and assessments are presented for thermomagnetic converter concepts and for thermoelastic converters (Nitinol heat engines). Reports prepared on previous occasions contain discussions on the following other direct conversion concepts: thermoelectric, pyroelectric, thermionic thermophotovoltaic and thermoacoustic; and also, more complete discussions of AMTEC and LMMHD systems. A tabulated summary of the various systems which have been reviewed thus far has been prepared. Some of the important technical research needs are listed and a schematic of each system is shown.

  2. Conversion of Questionnaire Data

    SciTech Connect

    Powell, Danny H; Elwood Jr, Robert H

    2011-01-01

    During the survey, respondents are asked to provide qualitative answers (well, adequate, needs improvement) on how well material control and accountability (MC&A) functions are being performed. These responses can be used to develop failure probabilities for basic events performed during routine operation of the MC&A systems. The failure frequencies for individual events may be used to estimate total system effectiveness using a fault tree in a probabilistic risk analysis (PRA). Numeric risk values are required for the PRA fault tree calculations that are performed to evaluate system effectiveness. So, the performance ratings in the questionnaire must be converted to relative risk values for all of the basic MC&A tasks performed in the facility. If a specific material protection, control, and accountability (MPC&A) task is being performed at the 'perfect' level, the task is considered to have a near zero risk of failure. If the task is performed at a less than perfect level, the deficiency in performance represents some risk of failure for the event. As the degree of deficiency in performance increases, the risk of failure increases. If a task that should be performed is not being performed, that task is in a state of failure. The failure probabilities of all basic events contribute to the total system risk. Conversion of questionnaire MPC&A system performance data to numeric values is a separate function from the process of completing the questionnaire. When specific questions in the questionnaire are answered, the focus is on correctly assessing and reporting, in an adjectival manner, the actual performance of the related MC&A function. Prior to conversion, consideration should not be given to the numeric value that will be assigned during the conversion process. In the conversion process, adjectival responses to questions on system performance are quantified based on a log normal scale typically used in human error analysis (see A.D. Swain and H.E. Guttmann

  3. Expanding discourse repertoires with hybridity

    NASA Astrophysics Data System (ADS)

    Kelly, Gregory J.

    2012-09-01

    In "Hybrid discourse practice and science learning" Kamberelis and Wehunt present a theoretically rich argument about the potential of hybrid discourses for science learning. These discourses draw from different forms of "talk, social practice, and material practices" to create interactions that are "intertextually complex" and "interactionally dynamic." The hybrid discourse practices are described as involving the dynamic interplay of at least three key elements: "the lamination of multiple cultural frames, the shifting relations between people and their discourse, and the shifting power relations between and among people." Each of these elements requires a respective unit of analysis and are often mutually reinforcing. The authors present a theoretically cogent argument for the study of hybrid discourse practices and identify the potential such discourses may have for science education. This theoretical development leads to an analysis of spoken and written discourse around a set of educational events concerning the investigation of owl pellets by two fifth grade students, their classmates, and teacher. Two discourse segments are presented and analyzed by the authors in detail. The first is a discourse analysis of the dissection of the owl pellet by two students, Kyle and Max. The second analysis examines the science report of these same two students. In this article, I pose a number of questions about the study with the hope that by doing so I expand the conversation around the insightful analysis presented.

  4. Mode conversion based on the acousto-optical interaction in photonic-phononic waveguide

    NASA Astrophysics Data System (ADS)

    Chen, Guodong; Zhang, Ruiwen; Xiong, Huang; Xie, Heng; Gao, Ya; Feng, Danqi; Sun, Junqiang

    2015-02-01

    We present a scheme for on-chip optical mode conversion in a hybrid photonic-phononic waveguide. Both propagating optical and acoustic wave can be tightly confined in the hybrid waveguide, and the acoustooptical interaction can be enhanced to realize optical mode conversion within a chip-scale size. The theoretical model of the acousto-optic interaction is established to explain the mode conversion. The numerical simulation results indicate that the high efficient mode conversion can be achieved by adjusting the intensity of the acoustic wave. We also show that the mode conversion bandwidth can be dramatically broadened to 13 THz by adjusting the frequency of the acoustic wave to match phase condition of the acousto-optic interaction. This mode converter on-chip is promising in order to increase the capacity of silicon data busses for on-chip optical interconnections.

  5. Hybrid Gear

    NASA Technical Reports Server (NTRS)

    Handschuh, Robert F. (Inventor); Roberts, Gary D. (Inventor)

    2016-01-01

    A hybrid gear consisting of metallic outer rim with gear teeth and metallic hub in combination with a composite lay up between the shaft interface (hub) and gear tooth rim is described. The composite lay-up lightens the gear member while having similar torque carrying capability and it attenuates the impact loading driven noise/vibration that is typical in gear systems. The gear has the same operational capability with respect to shaft speed, torque, and temperature as an all-metallic gear as used in aerospace gear design.

  6. Tables and conversions for microclimatology.

    Treesearch

    James M. Brown

    1973-01-01

    A series of tables, charts, and conversion factors have been prepared for use in microclimatic and ecological studies. Included are: the solution to various equations of radiant energy exchange; solar radiation diagrams; psychometric and precipitation data; and unit conversion factors.

  7. Conceptual design and system analysis study for a hybrid solar photovoltaic/solar thermal electric power system. Volume 2: Study results

    NASA Astrophysics Data System (ADS)

    1981-07-01

    A hybrid photovoltaic/solar thermal electric conversion system is described. Several types of hybrid systems, photovoltaic only systems, and solar thermal electric systems were compared in performance and cost. It is found that hybrid systems potentially competitive with photovoltaic only or solar thermal electric conversion systems. However, hybrid systems do not appear to have a significant advantage on a levelized cost per kilowatt hour basis.

  8. Conceptual design and system-analysis study for a hybrid solar photovoltaic/solar thermal electric power system. Volume 1: Executive summary

    NASA Astrophysics Data System (ADS)

    1981-07-01

    Studies on hybrid photovoltaic/solar thermal electric conversion systems are summarized. Several types of hybrid systems, photovoltaic only systems, and solar thermal electric systems were compared on performance and cost. Hybrid systems are shown to be competitive with photovoltaic only or solar thermal electric conversion systems, however, hybrid systems do not appear to have a significant advantage on a levelized cost per kilowatt hour basis.

  9. Hybrid energy harvesting using active thermal backplane

    NASA Astrophysics Data System (ADS)

    Kim, Hyun-Wook; Lee, Dong-Gun

    2016-04-01

    In this study, we demonstrate the concept of a new hybrid energy harvesting system by combing solar cells with magneto-thermoelectric generator (MTG, i.e., thermal energy harvesting). The silicon solar cell can easily reach high temperature under normal operating conditions. Thus the heated solar cell becomes rapidly less efficient as the temperature of solar cell rises. To increase the efficiency of the solar cell, air or water-based cooling system is used. To surpass conventional cooling devices requiring additional power as well as large working space for air/water collectors, we develop a new technology of pairing an active thermal backplane (ATB) to solar cell. The ATB design is based on MTG technology utilizing the physics of the 2nd order phase transition of active ferromagnetic materials. The MTG is cost-effective conversion of thermal energy to electrical energy and is fundamentally different from Seebeck TEG devices. The ATB (MTG) is in addition to being an energy conversion system, a very good conveyor of heat through both conduction and convection. Therefore, the ATB can provide dual-mode for the proposed hybrid energy harvesting. One is active convective and conductive cooling for heated solar cell. Another is active thermal energy harvesting from heat of solar cell. These novel hybrid energy harvesting device have potentially simultaneous energy conversion capability of solar and thermal energy into electricity. The results presented can be used for better understanding of hybrid energy harvesting system that can be integrated into commercial applications.

  10. Microbial Energy Conversion

    SciTech Connect

    Buckley, Merry; Wall, Judy D.

    2006-10-01

    The American Academy of Microbiology convened a colloquium March 10-12, 2006, in San Francisco, California, to discuss the production of energy fuels by microbial conversions. The status of research into various microbial energy technologies, the advantages and disadvantages of each of these approaches, research needs in the field, and education and training issues were examined, with the goal of identifying routes for producing biofuels that would both decrease the need for fossil fuels and reduce greenhouse gas emissions. Currently, the choices for providing energy are limited. Policy makers and the research community must begin to pursue a broader array of potential energy technologies. A diverse energy portfolio that includes an assortment of microbial energy choices will allow communities and consumers to select the best energy solution for their own particular needs. Funding agencies and governments alike need to prepare for future energy needs by investing both in the microbial energy technologies that work today and in the untested technologies that will serve the world’s needs tomorrow. More mature bioprocesses, such as ethanol production from starchy materials and methane from waste digestors, will find applications in the short term. However, innovative techniques for liquid fuel or biohydrogen production are among the longer term possibilities that should also be vigorously explored, starting now. Microorganisms can help meet human energy needs in any of a number of ways. In their most obvious role in energy conversion, microorganisms can generate fuels, including ethanol, hydrogen, methane, lipids, and butanol, which can be burned to produce energy. Alternatively, bacteria can be put to use in microbial fuel cells, where they carry out the direct conversion of biomass into electricity. Microorganisms may also be used some day to make oil and natural gas technologies more efficient by sequestering carbon or by assisting in the recovery of oil and

  11. Crucial Conversations about America's Schools

    ERIC Educational Resources Information Center

    Draper, John C.; Protheroe, Nancy

    2010-01-01

    It's up to school leaders to shift the momentum away from conversations based on misperceptions and toward those that study critical issues about school improvement. "Crucial Conversations About America's Schools" talks about how to do this and provides examples of how to reframe conversations on the hot-button but important topics of…

  12. The Personal Enjoyment of Conversation.

    ERIC Educational Resources Information Center

    Keller, Paul W.

    Conversation reminds us that we are not alone, that shared language is the opportunity to try on our many masks to see how many of them we can do without. The variety of pleasures accrued from conversation--"layers of pleasure"--deepen only as they move away from the individual orbits into the circle of mutual experience. When conversation is…

  13. Crucial Conversations about America's Schools

    ERIC Educational Resources Information Center

    Draper, John C.; Protheroe, Nancy

    2010-01-01

    It's up to school leaders to shift the momentum away from conversations based on misperceptions and toward those that study critical issues about school improvement. "Crucial Conversations About America's Schools" talks about how to do this and provides examples of how to reframe conversations on the hot-button but important topics of…

  14. Special Features in Children's Conversations.

    ERIC Educational Resources Information Center

    Karjalainen, Merja

    In a study of features that seem to be typical of children's conversations, 10 Finnish preschool children's conversations were videotaped and audiotaped over a period of 10 hours. The children were taped in conversation, play, fairy tale, and eating situations. Among the findings are that all children enjoy playing with language, but some initiate…

  15. Hybrid Simulator

    SciTech Connect

    Trujillo, David J.; Sridharan, Srikesh; Weinstock, Irvin

    2005-10-15

    HybSim (short for Hybrid Simulator) is a flexible, easy to use screening tool that allows the user to quanti the technical and economic benefits of installing a village hybrid generating system and simulates systems with any combination of —Diesel generator sets —Photovoltaic arrays -Wind Turbines and -Battery energy storage systems Most village systems (or small population sites such as villages, remote military bases, small communities, independent or isolated buildings or centers) depend on diesel generation systems for their source of energy. HybSim allows the user to determine other "sources" of energy that can greatly reduce the dollar to kilo-watt hour ratio. Supported by the DOE, Energy Storage Program, HybSim was initially developed to help analyze the benefits of energy storage systems in Alaskan villages. Soon after its development, other sources of energy were added providing the user with a greater range of analysis opportunities and providing the village with potentially added savings. In addition to village systems, HybSim has generated interest for use from military institutions in energy provisions and USAID for international village analysis.

  16. Portraits of colloidal hybrid nanostructures: controlled synthesis and potential applications.

    PubMed

    Nguyen, Thanh-Dinh

    2013-03-01

    Inorganic hybrid nanostructures containing two or more nanocomponents have been emerging in many areas of materials science in recent years. The particle-particle interactions in a hybrid particle system could significantly improve existing local electronic structure and induce tunable physiochemical responses. The current work reviews the diverse inorganic hybrid nanostructures formed by adhesion of the different single components via seed-mediated method. The hybrid nanomaterials have great potentials for real applications in many other fields. The nanohybrids have been used as efficient heterocatalysts for carbon monoxide conversion and photodegradation of organic contaminants. The enhanced catalytic activity of these hybrid nanocatalysts could be attributed the formation of oxygen vacancies and electron transfer across the structural junction in a hybrid system as a result of the interfacial particle-particle interactions. The synergistic combination of up-converting and semiconducting properties in an up-converting semiconducting hybrid particle results in appearance of sub-band-gap photoconductivity. This behavior has a great significance for the design of photovoltaic devices for effective solar energy conversion. The functionalization and subsequent bioconjugation of the hybrid nanostructures to afford the multifunctional nanomedical platforms for simultaneous diagnosis and therapy are reviewed. The conjugated multifunctional hybrid nanostructures exhibit high biocompatibility and highly selective binding with functional groups-fabricated alive organs through delivering them to the tumor sites. The clever combinations of multifunctional features and antibody conjugation within these vehicles make them to generally offer new opportunities for clinical diagnostics and therapeutics.

  17. Zinc phosphate conversion coatings

    DOEpatents

    Sugama, T.

    1997-02-18

    Zinc phosphate conversion coatings for producing metals which exhibit enhanced corrosion prevention characteristics are prepared by the addition of a transition-metal-compound promoter comprising a manganese, iron, cobalt, nickel, or copper compound and an electrolyte such as polyacrylic acid, polymethacrylic acid, polyitaconic acid and poly-L-glutamic acid to a phosphating solution. These coatings are further improved by the incorporation of Fe ions. Thermal treatment of zinc phosphate coatings to generate {alpha}-phase anhydrous zinc phosphate improves the corrosion prevention qualities of the resulting coated metal. 33 figs.

  18. Zinc phosphate conversion coatings

    DOEpatents

    Sugama, Toshifumi

    1997-01-01

    Zinc phosphate conversion coatings for producing metals which exhibit enhanced corrosion prevention characteristics are prepared by the addition of a transition-metal-compound promoter comprising a manganese, iron, cobalt, nickel, or copper compound and an electrolyte such as polyacrylic acid, polymethacrylic acid, polyitaconic acid and poly-L-glutamic acid to a phosphating solution. These coatings are further improved by the incorporation of Fe ions. Thermal treatment of zinc phosphate coatings to generate .alpha.-phase anhydrous zinc phosphate improves the corrosion prevention qualities of the resulting coated metal.

  19. Conversing Cooperatively: Using "Mini-Conversations" to Develop Conversational Knowledge and Skill

    ERIC Educational Resources Information Center

    Jones, Elizabeth B.

    2017-01-01

    Courses: Interpersonal communication, relational communication, language and social interaction, professional communication, interviewing practices. Objectives: This single class activity enables students to understand the theoretical foundations of conversation and to develop their conversational skills by talking in dyads with classmates. Upon…

  20. Morphological variation of genetically confirmed Alouatta Pigra × A. palliata hybrids from a natural hybrid zone in Tabasco, Mexico.

    PubMed

    Kelaita, Mary A; Cortés-Ortiz, Liliana

    2013-02-01

    While hybridization has been reported for a large number of primate taxa, there is a general lack of data on hybrid morphology for wild individuals with known genetic ancestry. A confirmed hybrid zone for the closely related Neotropical primates Alouatta palliata and A. pigra has provided a unique opportunity to study primate hybrid morphological variation. Here we used molecular evidence based on mitochondrial, Y-chromosome, and autosomal data to assess hybrid ancestry. We conducted univariate and multivariate statistical comparisons of morphometric data collected from individuals both outside and within the hybrid zone in Tabasco, Mexico. Our results show that of all the hybrids detected (N = 128), only 12% of them were approximately genetically intermediate, and none of them were first generation hybrids. Univariate pairwise comparisons among parental individuals, multigenerational backcrossed hybrids, and intermediate hybrids showed that overall, multigenerational backcrossed hybrids resemble the parental species with which they share most of their alleles. Conversely, intermediates were highly variable. Similarly, principal component analysis depicts an overlap between the parental species and their backcrosses when considering overall morphological differences. Finally, discriminant function analysis of the morphological variables was overall unreliable for classifying individuals into their assigned genotypic classes. Taken together, our results suggest that primate natural hybridization studies should incorporate molecular methods for determining ancestry, because morphology may not always be a reliable indicator of hybrid status. Hybrid zones could comprise a large number of multigenerational backcrossed hybrids that are indistinguishable from the parental species. The implications for studying hybridization in the primate fossil record are discussed. Copyright © 2012 Wiley Periodicals, Inc.

  1. Direct somatic lineage conversion

    PubMed Central

    Tanabe, Koji; Haag, Daniel; Wernig, Marius

    2015-01-01

    The predominant view of embryonic development and cell differentiation has been that rigid and even irreversible epigenetic marks are laid down along the path of cell specialization ensuring the proper silencing of unrelated lineage programmes. This model made the prediction that specialized cell types are stable and cannot be redirected into other lineages. Accordingly, early attempts to change the identity of somatic cells had little success and was limited to conversions between closely related cell types. Nuclear transplantation experiments demonstrated, however, that specialized cells even from adult mammals can be reprogrammed into a totipotent state. The discovery that a small combination of transcription factors can reprogramme cells to pluripotency without the need of oocytes further supported the view that these epigenetic barriers can be overcome much easier than assumed, but the extent of this flexibility was still unclear. When we showed that a differentiated mesodermal cell can be directly converted to a differentiated ectodermal cell without a pluripotent intermediate, it was suggested that in principle any cell type could be converted into any other cell type. Indeed, the work of several groups in recent years has provided many more examples of direct somatic lineage conversions. Today, the question is not anymore whether a specific cell type can be generated by direct reprogramming but how it can be induced. PMID:26416679

  2. Conversion program in Sweden

    SciTech Connect

    Jonsson, E.B.

    1997-08-01

    The conversion of the Swedish 50 MW R2 reactor from HEU to LEU fuel has been successfully accomplished over a 16 cycles long process. The conversion started in January 1991 with the introduction of 6 LEU assemblies in the 8*8 core. The first all LEU core was loaded in March 1993 and physics measurements were performed for the final licensing reports. A total of 142 LEU fuel assemblies have been irradiated up until September 1994 without any fuel incident. The operating licence for the R2 reactor was renewed in mid 1994 taking into account new fuel type. The Swedish Nuclear Inspectorate (SKI) pointed out one crucial problem with the LEU operation, that the back end of the LEU fuel cycle has not yet been solved. For the HEU fuel Sweden had the reprocessing alternative. The country is now relying heavily on the success of the USDOEs Off Site Fuels Policy to take back the spent fuel from the research reactors. They have in the meantime increased their intermediate storage facilities. There is, however, a limit both in time and space for storage of MTR-type of assemblies in water. The penalty of the lower thermal neutron flux in LEU cores has been reduced by improvements of the new irradiation rigs and by fine tuning the core calculations. The Studsvik code package, CASMO-SIMULATE, widely used for ICFM in LWRs has been modified to suit the compact MTR type of core.

  3. Energy conversion system

    SciTech Connect

    Murphy, Lawrence M.

    1987-01-01

    The energy conversion system includes a photo-voltaic array for receiving solar radiation and converting such radiation to electrical energy. The photo-voltaic array is mounted on a stretched membrane that is held by a frame. Tracking means for orienting the photo-voltaic array in predetermined positions that provide optimal exposure to solar radiation cooperate with the frame. An enclosure formed of a radiation transmissible material includes an inside containment space that accommodates the photo-voltaic array on the stretched membrane, the frame and the tracking means, and forms a protective shield for all such components. The enclosure is preferably formed of a flexible inflatable material and maintains its preferred form, such as a dome, under the influence of a low air pressure furnished to the dome. Under this arrangement the energy conversion system is streamlined for minimizing wind resistance, sufficiently weatherproof for providing protection against weather hazards such as hail, capable of using diffused light, lightweight for low-cost construction, and operational with a minimal power draw.

  4. Natural gas conversion process

    SciTech Connect

    Not Available

    1991-01-01

    The main objective is to design and operate a laboratory apparatus for the catalytic reforming of natural gas in order to provide data for a large-scale process. To accelerate the assembly and calibration of this equipment, a request has been made to the Lawrence Berkeley Laboratory for assistance, under the DOE's Industrial Visitor Exchange Program. Pr. Heinz Heinemann (Catalysis), Dr. John Apps (Geochemistry) and Dr. Robert Fulton (Mechanical Engineering) have expressed interest in supporting our request. Pr. Heinemann's recent results on the conversion of Petroleum Coke residues into CO2 and H2 mixtures using highly basic metal oxides catalysts, similar to ours, are very encouraging regarding the possibility of converting the Coke residue on our catalyst into Syngas in the Regenerator/riser, as proposed. To minimize Coke formation in the vapor phase, by the Plasmapyrolytic Methane Conversion reactions, the experimental data of H. Drost et al. (Ref. 12) have been reviewed. Work is underway to design equipment for the safe and non-polluting disposal of the two gaseous product streams of the flow loop. 2 refs.

  5. Mode conversion in ITER

    NASA Astrophysics Data System (ADS)

    Jaeger, E. F.; Berry, L. A.; Myra, J. R.

    2006-10-01

    Fast magnetosonic waves in the ion cyclotron range of frequencies (ICRF) can convert to much shorter wavelength modes such as ion Bernstein waves (IBW) and ion cyclotron waves (ICW) [1]. These modes are potentially useful for plasma control through the generation of localized currents and sheared flows. As part of the SciDAC Center for Simulation of Wave-Plasma Interactions project, the AORSA global-wave solver [2] has been ported to the new, dual-core Cray XT-3 (Jaguar) at ORNL where it demonstrates excellent scaling with the number of processors. Preliminary calculations using 4096 processors have allowed the first full-wave simulations of mode conversion in ITER. Mode conversion from the fast wave to the ICW is observed in mixtures of deuterium, tritium and helium3 at 53 MHz. The resulting flow velocity and electric field shear will be calculated. [1] F.W. Perkins, Nucl. Fusion 17, 1197 (1977). [2] E.F. Jaeger, L.A. Berry, J.R. Myra, et al., Phys. Rev. Lett. 90, 195001-1 (2003).

  6. Energy conversion system

    DOEpatents

    Murphy, L.M.

    1985-09-16

    The energy conversion system includes a photo-voltaic array for receiving solar radiation and converting such radiation to electrical energy. The photo-voltaic array is mounted on a stretched membrane that is held by a frame. Tracking means for orienting the photo-voltaic array in predetermined positions that provide optimal exposure to solar radiation cooperate with the frame. An enclosure formed of a radiation transmissible material includes an inside containment space that accommodates the photo-voltaic array on the stretched membrane, the frame and the tracking means, and forms a protective shield for all such components. The enclosure is preferably formed of a flexible inflatable material and maintains its preferred form, such as a dome, under the influence of a low air pressure furnished to the dome. Under this arrangement the energy conversion system is streamlined for minimizing wind resistance, sufficiently weathproof for providing protection against weather hazards such as hail, capable of using diffused light, lightweight for low-cost construction and operational with a minimal power draw.

  7. Spatial language and converseness.

    PubMed

    Burigo, Michele; Coventry, Kenny R; Cangelosi, Angelo; Lynott, Dermot

    2016-12-01

    Typical spatial language sentences consist of describing the location of an object (the located object) in relation to another object (the reference object) as in "The book is above the vase". While it has been suggested that the properties of the located object (the book) are not translated into language because they are irrelevant when exchanging location information, it has been shown that the orientation of the located object affects the production and comprehension of spatial descriptions. In line with the claim that spatial language apprehension involves inferences about relations that hold between objects it has been suggested that during spatial language apprehension people use the orientation of the located object to evaluate whether the logical property of converseness (e.g., if "the book is above the vase" is true, then also "the vase is below the book" must be true) holds across the objects' spatial relation. In three experiments using sentence acceptability rating tasks we tested this hypothesis and demonstrated that when converseness is violated people's acceptability ratings of a scene's description are reduced indicating that people do take into account geometric properties of the located object and use it to infer logical spatial relations.

  8. Light alkane conversion

    SciTech Connect

    Harandi, M.N.; Owen, H.

    1991-07-09

    This patent describes a process for the aromatization of an aliphatic feedstream. It comprises fluidizing finely divided solid particles in a combustion zone; charging oxygen-containing combustion gas and fuel to the combustion zone under combustion conditions; withdrawing a stream of finely divided particles from the combustion zone; flowing the withdrawn stream of finely divided particles above to a cracking/dehydrogenation zone; fluidizing the finely divided particles above in an aliphatic feedstream under conditions within the cracking/dehydrogenation zone controlled to at least partially crack and at least partially dehydrogenate the aliphatic feedstream to form an intermediate product stream containing a quantity of C{sub 4}-olefins such that the exothermic catalytic conversion of the C{sub 4}-olefins is sufficient to supply a portion of the endothermic heat of reaction for the endothermic catalytic conversion of paraffins contained in the intermediate feedstream to aromatics; contacting the intermediate product stream with an aromatization catalyst under aromatization conditions sufficient to evolve an aromatics-rich products stream.

  9. Hybrid piezoelectric energy harvesting transducer system

    NASA Technical Reports Server (NTRS)

    Xu, Tian-Bing (Inventor); Jiang, Xiaoning (Inventor); Su, Ji (Inventor); Rehrig, Paul W. (Inventor); Hackenberger, Wesley S. (Inventor)

    2008-01-01

    A hybrid piezoelectric energy harvesting transducer system includes: (a) first and second symmetric, pre-curved piezoelectric elements mounted separately on a frame so that their concave major surfaces are positioned opposite to each other; and (b) a linear piezoelectric element mounted separately on the frame and positioned between the pre-curved piezoelectric elements. The pre-curved piezoelectric elements and the linear piezoelectric element are spaced from one another and communicate with energy harvesting circuitry having contact points on the frame. The hybrid piezoelectric energy harvesting transducer system has a higher electromechanical energy conversion efficiency than any known piezoelectric transducer.

  10. Hybridized tetraquarks

    DOE PAGES

    Esposito, Angelo; Pilloni, Alessadro; Polosa, A. D.

    2016-05-12

    In this study, we propose a new interpretation of the neutral and charged X,Z exotic hadron resonances. Hybridized-tetraquarks are neither purely compact tetraquark states nor bound or loosely bound molecules. The latter would require a negative or zero binding energy whose counterpart in h-tetraquarks is a positive quantity. The formation mechanism of this new class of hadrons is inspired by that of Feshbach metastable states in atomic physics. The recent claim of an exotic resonance in the B0s π± channel by the D0 collaboration and the negative result presented subsequently by the LHCb collaboration are understood in this scheme, togethermore » with a considerable portion of available data on X, Z particles. Considerations on a state with the same quantum numbers as the X(5568) are also made.« less

  11. Hybrid polymer-nanocrystal materials for photovoltaic applications.

    PubMed

    Zhou, Renjia; Xue, Jiangeng

    2012-07-16

    Hybrid polymer-nanocrystal photovoltaic (PV) cells have received much attention during the past decade as promising low-cost solar energy harvesting devices, and showed significant progress with power conversion efficiency reaching 5% recently. This review starts from the introduction of hybrid materials to their application in electronic devices, with particular focus on bulk-heterojunction hybrid polymer-nanocrystal PV devices. The synthesis, surface chemistry, and electronic properties of colloidal inorganic nanocrystals are described. The recent development of hybrid PV devices will be discussed from the perspective of tailoring both inorganic nanocrystals and conjugated polymers, controlling polymer-nanocrystal hybrid morphology, engineering polymer-nanocrystal interface, and optimizing device architecture. Finally, future directions for further advancing hybrid PV technology to potential commercialization are also discussed.

  12. Enhancing The Mode Conversion Efficiency In JET Plasmas With Multiple Mode Conversion Layers

    NASA Astrophysics Data System (ADS)

    Van Eester, D.; Lerche, E.; Johnson, T.; Hellsten, T.; Ongena, J.; Mayoral, M.-L.; Frigione, D.; Sozzi, C.; Calabro, G.; Lennholm, M.; Beaumont, P.; Blackman, T.; Brennan, D.; Brett, A.; Cecconello, M.; Coffey, I.; Coyne, A.; Crombe, K.; Czarnecka, A.; Felton, R.; Johnson, M. Gatu; Giroud, C.; Gorini, G.; Hellesen, C.; Jacquet, P.; Kazakov, Y.; Kiptily, V.; Knipe, S.; Krasilnikov, A.; Lin, Y.; Maslov, M.; Monakhov, I.; Noble, C.; Nocente, M.; Pangioni, L.; Proverbio, I.; Stamp, M.; Studholme, W.; Tardocchi, M.; Versloot, T. W.; Vdovin, V.; Whitehurst, A.; Wooldridge, E.; Zoita, V.

    2011-12-01

    The constructive interference effect described by Fuchs et al. [1] shows that the mode conversion and thereby the overall heating efficiency can be enhanced significantly when an integer number of fast wave wavelengths can be folded in between the high field side fast wave cutoff and the ion-ion hybrid layer(s) at which the ion Bernstein or ion cyclotron waves are excited. This effect was already experimentally identified in (3He)-D plasmas [2] and was recently tested in (3He)-H JET plasmas. The latter is an `inverted' scenario, which differs significantly from the (3He)-D scenarios since the mode-conversion layer is positioned between the low field side edge of the plasma and the ion-cyclotron layer of the minority 3He ions (whereas the order in which a wave entering the plasma from the low field side encounters these layers is inverted in a `regular' scenario), and because much lower 3He concentrations are needed to achieve the mode-conversion heating regime. The presence of small amounts of 4He and D in the discharges gave rise to an additional mode conversion layer on top of the expected one associated with 3He-H, which made the interpretation of the results more complex but also more interesting: Three different regimes could be distinguished as a function of X[3He], and the differing dynamics at the various concentrations could be traced back to the presence of these two mode conversion layers and their associated fast wave cutoffs. Whereas (1-D and 2-D) numerical modeling yields quantitative information on the RF absorptivity, recent analytical work by Kazakov [3] permits to grasp the dominant underlying wave interaction physics.

  13. Silicon nanocrystal-noble metal hybrid nanoparticles

    NASA Astrophysics Data System (ADS)

    Sugimoto, H.; Fujii, M.; Imakita, K.

    2016-05-01

    We report a novel and facile self-limiting synthesis route of silicon nanocrystal (Si NC)-based colloidally stable semiconductor-metal (gold, silver and platinum) hybrid nanoparticles (NPs). For the formation of hybrid NPs, we employ ligand-free colloidal Si NCs with heavily boron (B) and phosphorus (P) doped shells. By simply mixing B and P codoped colloidal Si NCs with metal salts, hybrid NPs consisting of metal cores and Si NC shells are spontaneously formed. We demonstrate the synthesis of highly uniform and size controllable hybrid NPs. It is shown that codoped Si NCs act as a reducing agent for metal salts and also as a protecting layer to stop metal NP growth. The process is thus self-limiting. The development of a variety of Si NC-based hybrid NPs is a promising first step for the design of biocompatible multifunctional NPs with broad material choices for biosensing, bioimaging and solar energy conversion.We report a novel and facile self-limiting synthesis route of silicon nanocrystal (Si NC)-based colloidally stable semiconductor-metal (gold, silver and platinum) hybrid nanoparticles (NPs). For the formation of hybrid NPs, we employ ligand-free colloidal Si NCs with heavily boron (B) and phosphorus (P) doped shells. By simply mixing B and P codoped colloidal Si NCs with metal salts, hybrid NPs consisting of metal cores and Si NC shells are spontaneously formed. We demonstrate the synthesis of highly uniform and size controllable hybrid NPs. It is shown that codoped Si NCs act as a reducing agent for metal salts and also as a protecting layer to stop metal NP growth. The process is thus self-limiting. The development of a variety of Si NC-based hybrid NPs is a promising first step for the design of biocompatible multifunctional NPs with broad material choices for biosensing, bioimaging and solar energy conversion. Electronic supplementary information (ESI) available: Additional TEM images and extinction spectra of Si-metal hybrid NPs are shown in Fig. S1

  14. Laser-accelerated proton conversion efficiency thickness scaling

    SciTech Connect

    Hey, D. S.; Foord, M. E.; Key, M. H.; LePape, S. L.; Mackinnon, A. J.; Patel, P. K.; Ping, Y.; Akli, K. U.; Stephens, R. B.; Bartal, T.; Beg, F. N.; Fedosejevs, R.; Friesen, H.; Tiedje, H. F.; Tsui, Y. Y.

    2009-12-15

    The conversion efficiency from laser energy into proton kinetic energy is measured with the 0.6 ps, 9x10{sup 19} W/cm{sup 2} Titan laser at the Jupiter Laser Facility as a function of target thickness in Au foils. For targets thicker than 20 {mu}m, the conversion efficiency scales approximately as 1/L, where L is the target thickness. This is explained by the domination of hot electron collisional losses over adiabatic cooling. In thinner targets, the two effects become comparable, causing the conversion efficiency to scale weaker than 1/L; the measured conversion efficiency is constant within the scatter in the data for targets between 5 and 15 {mu}m, with a peak conversion efficiency of 4% into protons with energy greater than 3 MeV. Depletion of the hydrocarbon contaminant layer is eliminated as an explanation for this plateau by using targets coated with 200 nm of ErH{sub 3} on the rear surface. The proton acceleration is modeled with the hybrid-particle in cell code LSP, which reproduced the conversion efficiency scaling observed in the data.

  15. GIM code user's manual for the STAR-100 computer. [for generating numerical analogs of the conversion laws

    NASA Technical Reports Server (NTRS)

    Spradley, L.; Pearson, M.

    1979-01-01

    The General Interpolants Method (GIM), a three dimensional, time dependent, hybrid procedure for generating numerical analogs of the conversion laws, is described. The Navier-Stokes equations written for an Eulerian system are considered. The conversion of the GIM code to the STAR-100 computer, and the implementation of 'GIM-ON-STAR' is discussed.

  16. Power conversion technologies

    SciTech Connect

    Newton, M. A.

    1997-02-01

    The Power Conversion Technologies thrust area identifies and sponsors development activities that enhance the capabilities of engineering at Lawrence Livermore National Laboratory (LLNL) in the area of solid- state power electronics. Our primary objective is to be a resource to existing and emerging LLNL programs that require advanced solid-state power electronic technologies.. Our focus is on developing and integrating technologies that will significantly impact the capability, size, cost, and reliability of future power electronic systems. During FY-96, we concentrated our research efforts on the areas of (1) Micropower Impulse Radar (MIR); (2) novel solid-state opening switches; (3) advanced modulator technology for accelerators; (4) compact accelerators; and (5) compact pulse generators.

  17. Advanced thermionic energy conversion

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Developments towards space and terrestrial applications of thermionic energy conversion are presented. Significant accomplishments for the three month period include: (1) devised a blade-type distributed lead design with many advantages compared to the stud-type distributed lead; (2) completed design of Marchuk tube test apparatus; (3) concluded, based on current understanding, that residual hydrogen should not contribute to a negative space charge barrier at the collector; (4) modified THX design program to include series-coupled designs as well as inductively-coupled designs; (5) initiated work on the heat transfer technology, THX test module, output power transfer system, heat transfer system, and conceptual plant design tasks; and (6) reached 2200 hours of operation in JPL-5 cylindrical converter envelope test.

  18. Automated FORTRAN conversion

    NASA Technical Reports Server (NTRS)

    Aharonian, Gregory

    1986-01-01

    The most pratical solution to the conversion of FORTRAN to other programming languages which STO and a few others have adopted, uses an intermediate language that is easy to translate FORTRAN into, and allows for source codes in other languages to be generated automatically. The intermediate language is the union of all other programming languages (and the trick is to create a useful union) with some extensions that reflect the nature of the algorithms. The benefits of this approach are many. First the original FORTRAN program has to be rewritten only once, and then only parts of the program: most FORTRAN code passes through without and change (i.e., assignment and simple IF statements). Software tools are provided to ease this initial translation. Once in the intermediate language, the algorithm can then be obtained in any other language automatically. An example of a subroutine from the Rispack library in ten different languages is given.

  19. Laser plasmadynamic energy conversion

    NASA Technical Reports Server (NTRS)

    Shimada, K.

    1976-01-01

    The generation of electrons ions by interacting an intense laser beam with cesium vapor is considered. Theoretical calculation shows that the conversion efficiency is as high as 40 percent if the entire photon energy is utilized in ionizing the cesium vapor that is generated initially by the incoming laser beam. An output voltage is expected to be generated across two electrodes, one of which is the liquid cesium, by keeping the other electrode at a different work function. Evaluation of the laser plasmadynamic (LPD) converter was performed using pulsed ruby and Nd-glass lasers. Although the results obtained to date indicate an efficiency smaller than that of theoretical predictions, an unoptimized LPD converter did demonstrate the capability of converting laser energy at large power levels. The limitations in the performance may by due to converter geometry, the types of lasers used, and other limitations inherent to the cesium plasma.

  20. Thermal Energy Conversion Branch

    NASA Technical Reports Server (NTRS)

    Bielozer, Matthew C.; Schreiber, Jeffrey, G.; Wilson, Scott D.

    2004-01-01

    The Thermal Energy Conversion Branch (5490) leads the way in designing, conducting, and implementing research for the newest thermal systems used in space applications at the NASA Glenn Research Center. Specifically some of the most advanced technologies developed in this branch can be broken down into four main areas: Dynamic Power Systems, Primary Solar Concentrators, Secondary Solar Concentrators, and Thermal Management. Work was performed in the Dynamic Power Systems area, specifically the Stirling Engine subdivision. Today, the main focus of the 5490 branch is free-piston Stirling cycle converters, Brayton cycle nuclear reactors, and heat rejection systems for long duration mission spacecraft. All space exploring devices need electricity to operate. In most space applications, heat energy from radioisotopes is converted to electrical power. The Radioisotope Thermoelectric Generator (RTG) already supplies electricity for missions such as the Cassini Spacecraft. The focus of today's Stirling research at GRC is aimed at creating an engine that can replace the RTG. The primary appeal of the Stirling engine is its high system efficiency. Because it is so efficient, the Stirling engine will significantly reduce the plutonium fuel mission requirements compared to the RTG. Stirling is also being considered for missions such as the lunar/Mars bases and rovers. This project has focused largely on Stirling Engines of all types, particularly the fluidyne liquid piston engine. The fluidyne was developed by Colin D. West. This engine uses the same concepts found in any type of Stirling engine, with the exception of missing mechanical components. All the working components are fluid. One goal was to develop and demonstrate a working Stirling Fluidyne Engine at the 2nd Annual International Energy Conversion Engineering Conference in Providence, Rhode Island.

  1. The Role of Conversation Policy in Carrying Out Agent Conversations

    SciTech Connect

    Link, Hamilton E.; Phillips, Laurence R.

    1999-05-20

    Structured conversation diagrams, or conversation specifications, allow agents to have predictable interactions and achieve predefined information-based goals, but they lack the flexibility needed to function robustly in an unpredictable environment. We propose a mechanism that combines a typical conversation structure with a separately established policy to generate an actual conversation. The word "policy" connotes a high-level direction external to a specific planned interaction with the environment. Policies, which describe acceptable procedures and influence decisions, can be applied to broad sets of activity. Based on their observation of issues related to a policy, agents may dynamically adjust their communication patterns. The policy object describes limitations, constraints, and requirements that may affect the conversation in certain circumstances. Using this new mechanism of interaction simplifies the description of individual conversations and allows domain-specific issues to be brought to bear more easily during agent communication. By following the behavior of the conversation specification when possible and deferring to the policy to derive behavior in exceptional circumstances, an agent is able to function predictably under normal situations and still act rationally in abnormal situations. Different conversation policies applied to a given conversation specification can change the nature of the interaction without changing the specification.

  2. Hybrid system of semiconductor and photosynthetic protein

    NASA Astrophysics Data System (ADS)

    Kim, Younghye; Shin, Seon Ae; Lee, Jaehun; Yang, Ki Dong; Nam, Ki Tae

    2014-08-01

    Photosynthetic protein has the potential to be a new attractive material for solar energy absorption and conversion. The development of semiconductor/photosynthetic protein hybrids is an example of recent progress toward efficient, clean and nanostructured photoelectric systems. In the review, two biohybrid systems interacting through different communicating methods are addressed: (1) a photosynthetic protein immobilized semiconductor electrode operating via electron transfer and (2) a hybrid of semiconductor quantum dots and photosynthetic protein operating via energy transfer. The proper selection of materials and functional and structural modification of the components and optimal conjugation between them are the main issues discussed in the review. In conclusion, we propose the direction of future biohybrid systems for solar energy conversion systems, optical biosensors and photoelectric devices.

  3. Hybrid system of semiconductor and photosynthetic protein.

    PubMed

    Kim, Younghye; Shin, Seon Ae; Lee, Jaehun; Yang, Ki Dong; Nam, Ki Tae

    2014-08-29

    Photosynthetic protein has the potential to be a new attractive material for solar energy absorption and conversion. The development of semiconductor/photosynthetic protein hybrids is an example of recent progress toward efficient, clean and nanostructured photoelectric systems. In the review, two biohybrid systems interacting through different communicating methods are addressed: (1) a photosynthetic protein immobilized semiconductor electrode operating via electron transfer and (2) a hybrid of semiconductor quantum dots and photosynthetic protein operating via energy transfer. The proper selection of materials and functional and structural modification of the components and optimal conjugation between them are the main issues discussed in the review. In conclusion, we propose the direction of future biohybrid systems for solar energy conversion systems, optical biosensors and photoelectric devices.

  4. Respiratory markers of conversational interaction.

    PubMed

    McFarland, D H

    2001-02-01

    Respiratory movements were recorded from 10 dyads (20 subjects) during quiet breathing, reading aloud, spontaneous monologue, scripted dialog, and spontaneous conversation. Timing measures of inspiratory, expiratory, and total cycle duration were used to compare respiratory function during quiet breathing, listening, and speech. Cross-correlation analyses of the respiratory movements of conversational partners provided an index of conversational synchrony. Inspiratory duration was found to be the most consistent and sensitive measure for discriminating quiet breathing from speech breathing. In the scripted dialog and spontaneous conversation conditions, respiratory kinematics changed during listening to more closely resemble speech, and systematic changes were observed in anticipation of turn-taking speech onset. For the breathing cycles immediately surrounding turn changes and simultaneously produced vocal events, the kinematic signals of conversational partners were strongly correlated. Results are discussed in the context of similar findings concerning conversational interactions and motor preparation for speech.

  5. Ultrafast Electron Dynamics in Solar Energy Conversion.

    PubMed

    Ponseca, Carlito S; Chábera, Pavel; Uhlig, Jens; Persson, Petter; Sundström, Villy

    2017-08-23

    Electrons are the workhorses of solar energy conversion. Conversion of the energy of light to electricity in photovoltaics, or to energy-rich molecules (solar fuel) through photocatalytic processes, invariably starts with photoinduced generation of energy-rich electrons. The harvesting of these electrons in practical devices rests on a series of electron transfer processes whose dynamics and efficiencies determine the function of materials and devices. To capture the energy of a photogenerated electron-hole pair in a solar cell material, charges of opposite sign have to be separated against electrostatic attractions, prevented from recombining and being transported through the active material to electrodes where they can be extracted. In photocatalytic solar fuel production, these electron processes are coupled to chemical reactions leading to storage of the energy of light in chemical bonds. With the focus on the ultrafast time scale, we here discuss the light-induced electron processes underlying the function of several molecular and hybrid materials currently under development for solar energy applications in dye or quantum dot-sensitized solar cells, polymer-fullerene polymer solar cells, organometal halide perovskite solar cells, and finally some photocatalytic systems.

  6. Hybrid mimics and hybrid vigor in Arabidopsis

    PubMed Central

    Wang, Li; Greaves, Ian K.; Groszmann, Michael; Wu, Li Min; Dennis, Elizabeth S.; Peacock, W. James

    2015-01-01

    F1 hybrids can outperform their parents in yield and vegetative biomass, features of hybrid vigor that form the basis of the hybrid seed industry. The yield advantage of the F1 is lost in the F2 and subsequent generations. In Arabidopsis, from F2 plants that have a F1-like phenotype, we have by recurrent selection produced pure breeding F5/F6 lines, hybrid mimics, in which the characteristics of the F1 hybrid are stabilized. These hybrid mimic lines, like the F1 hybrid, have larger leaves than the parent plant, and the leaves have increased photosynthetic cell numbers, and in some lines, increased size of cells, suggesting an increased supply of photosynthate. A comparison of the differentially expressed genes in the F1 hybrid with those of eight hybrid mimic lines identified metabolic pathways altered in both; these pathways include down-regulation of defense response pathways and altered abiotic response pathways. F6 hybrid mimic lines are mostly homozygous at each locus in the genome and yet retain the large F1-like phenotype. Many alleles in the F6 plants, when they are homozygous, have expression levels different to the level in the parent. We consider this altered expression to be a consequence of transregulation of genes from one parent by genes from the other parent. Transregulation could also arise from epigenetic modifications in the F1. The pure breeding hybrid mimics have been valuable in probing the mechanisms of hybrid vigor and may also prove to be useful hybrid vigor equivalents in agriculture. PMID:26283378

  7. Hybrid mimics and hybrid vigor in Arabidopsis.

    PubMed

    Wang, Li; Greaves, Ian K; Groszmann, Michael; Wu, Li Min; Dennis, Elizabeth S; Peacock, W James

    2015-09-01

    F1 hybrids can outperform their parents in yield and vegetative biomass, features of hybrid vigor that form the basis of the hybrid seed industry. The yield advantage of the F1 is lost in the F2 and subsequent generations. In Arabidopsis, from F2 plants that have a F1-like phenotype, we have by recurrent selection produced pure breeding F5/F6 lines, hybrid mimics, in which the characteristics of the F1 hybrid are stabilized. These hybrid mimic lines, like the F1 hybrid, have larger leaves than the parent plant, and the leaves have increased photosynthetic cell numbers, and in some lines, increased size of cells, suggesting an increased supply of photosynthate. A comparison of the differentially expressed genes in the F1 hybrid with those of eight hybrid mimic lines identified metabolic pathways altered in both; these pathways include down-regulation of defense response pathways and altered abiotic response pathways. F6 hybrid mimic lines are mostly homozygous at each locus in the genome and yet retain the large F1-like phenotype. Many alleles in the F6 plants, when they are homozygous, have expression levels different to the level in the parent. We consider this altered expression to be a consequence of transregulation of genes from one parent by genes from the other parent. Transregulation could also arise from epigenetic modifications in the F1. The pure breeding hybrid mimics have been valuable in probing the mechanisms of hybrid vigor and may also prove to be useful hybrid vigor equivalents in agriculture.

  8. Solar energy conversion apparatus

    SciTech Connect

    Nash, S.G.

    1983-10-18

    Solar energy conversion apparatus is disclosed including a housing portion, an energy absorbing portion, a fluid directing portion and a cover portion; the housing portion including a molded plastic pan member including a base section with upwardly extending spaced spacer sections, the pan member including outwardly inclined sidewall sections having spaced inner and outer wall sections with a top section including an outwardly extending flange section and an inwardly extending slotted frame section; the energy absorbing portion including a conductive metal liner member positioned within the housing portion and resting on the upper surfaces of the spacer sections, a conductive metal separator section extending between the liner sidewall sections adjacent the upper ends thereof and enclosing the liner member; the fluid directing portion including a plurality of parallel spaced longitudinal baffle members arranged in a staggered relationship to provide a tortuous fluid path through the apparatus, an inlet opening and an outlet opening to the tortuous path, the baffle members extending upwardly from the liner bottom to the separator section; the cover portion including transparent impact resistant flat and dome members, the edges of the flat member being secured to the top section, the dome member being disposed over the flat member with its edges engaged with the flange section slots, the dome member including flat sections extending upwardly at an angle of 20/sup 0/ to 30/sup 0/ and a convex central section joining the flat sections.

  9. Reactor for methane conversion

    SciTech Connect

    Bader, R.A.; Axelrod, M.G.

    1989-08-08

    This patent describes a reactor adapted for the conversion of methane to higher molecular weight hydrocarbons. It comprises a central support column and an outer shell which together define an annular reaction zone, inlet means for introducing a mixture of methane containing gas and fluidized solid catalyst particles into the reaction zone, and outlet means for withdrawing a mixture of gas and fluidized solid catalyst particles from the zone, and a plurality of vertically spaced ceramic baffle assemblies comprised of wedged-shaped segments positioned in the reaction zone each perpendicular to the central support column and the outer shell. The baffle assemblies filling the annular cross-section between the support column and the outer shell and being supported at the outer wall of the central support column and at the inner wall of the outer shell, adjacent baffle assembly segments also being supported by radial ceramic support beams. The baffle assemblies each having a plurality of openings 0.25 to 3 inches in diameter adapted to permit passage of the mixture of gas and fluidized solid catalyst particles through the baffle assemblies only toward the outlet means, the area of the openings being 10-70% of the baffle area of each baffle assembly.

  10. Geothermal energy conversion facility

    SciTech Connect

    Kutscher, C.F.

    1997-12-31

    With the termination of favorable electricity generation pricing policies, the geothermal industry is exploring ways to improve the efficiency of existing plants and make them more cost-competitive with natural gas. The Geothermal Energy Conversion Facility (GECF) at NREL will allow researchers to study various means for increasing the thermodynamic efficiency of binary cycle geothermal plants. This work has received considerable support from the US geothermal industry and will be done in collaboration with industry members and utilities. The GECF is being constructed on NREL property at the top of South Table Mountain in Golden, Colorado. As shown in Figure 1, it consists of an electrically heated hot water loop that provides heating to a heater/vaporizer in which the working fluid vaporizes at supercritical or subcritical pressures as high as 700 psia. Both an air-cooled and water-cooled condenser will be available for condensing the working fluid. In order to minimize construction costs, available equipment from the similar INEL Heat Cycle Research Facility is being utilized.

  11. Microbial conversion of coal

    SciTech Connect

    Bean, R.M. )

    1989-10-01

    The objectives of this project were to describe in detail the degradation of coals by fungi and microbes, to expand the range of applicability of the process to include new microbes and other coal types, to identify the means by which biosolubilization of coal is accomplished, and to explore means to enhance the rates and extent of coal bioconversion. The project was initiated in a response to the discovery by Dr. Martin Cohen at the University of Hartford, of a fungal strain of Coriolus versicolor that would render a solid coal substance, leonardite, into a liquid product. The project has identified the principal agent of leonardite solubilization as a powerful metal chelator, most likely a fungal-produced siderophore. Another nonlaccase enzyme has also been identified as a unique biosolubilizing agent produced by C. versicolor. Assays were developed for the quantitative determination of biological coal conversion, and for the determination of potency of biosolubilizing agent. Screening studies uncovered several microbial organisms capable of coal biodegradation, and led to the discovery that prolonged heating in air at the moderate temperature of 150{degree}C allowed the biodegradation of Illinois {number sign}6 coal to material soluble in dilute base. Chemical studies showed that leonardite biosolubilization was accompanied by relatively small change in composition, while solubilization of Illinois {number sign}6 coal involves considerable oxidation of the coal. 24 refs., 32 figs., 27 tabs.

  12. Energy conversion apparatus

    SciTech Connect

    Porter, D.R.

    1988-10-18

    This patent describes an energy conversion apparatus comprising: an engine, the engine comprising a cylinder and a piston reciprocally mounted therein, the cylinder defining a combustion chamber on one side of the piston for receiving a fuel mixture and a fluid drive chamber on the other side of the piston for receiving hydraulic fluid, a turbine, the turbine comprising a housing and a vaned turbine wheel rotatably mounted on a drive shaft journalled in the housing, hydraulic means for coupling fluid in the fluid drive chamber of the cylinder with the housing for rotatably driving the turbine wheel and the drive shaft upon a given movement of the piston, means for providing the combustion chamber of the engine with a fuel mixture comprising hydrogen and oxygen, an ignition means for selectively igniting the mixture in the combustion chamber, and purging means for selectively rotating the turbine prior to ignition of the fuel mixture in the engine to remove air therefrom, the purging means comprising a pump means for moving fluid from the reservoir into the fluid drive chambers, the conduit means and the turbine housing, whereby the piston driven by the ignited fuel mixture forces fluid in the fluid drive chamber against the vanes of the turbine wheel to rotate the drive shaft.

  13. GPU color space conversion

    NASA Astrophysics Data System (ADS)

    Chase, Patrick; Vondran, Gary

    2011-01-01

    Tetrahedral interpolation is commonly used to implement continuous color space conversions from sparse 3D and 4D lookup tables. We investigate the implementation and optimization of tetrahedral interpolation algorithms for GPUs, and compare to the best known CPU implementations as well as to a well known GPU-based trilinear implementation. We show that a 500 NVIDIA GTX-580 GPU is 3x faster than a 1000 Intel Core i7 980X CPU for 3D interpolation, and 9x faster for 4D interpolation. Performance-relevant GPU attributes are explored including thread scheduling, local memory characteristics, global memory hierarchy, and cache behaviors. We consider existing tetrahedral interpolation algorithms and tune based on the structure and branching capabilities of current GPUs. Global memory performance is improved by reordering and expanding the lookup table to ensure optimal access behaviors. Per multiprocessor local memory is exploited to implement optimally coalesced global memory accesses, and local memory addressing is optimized to minimize bank conflicts. We explore the impacts of lookup table density upon computation and memory access costs. Also presented are CPU-based 3D and 4D interpolators, using SSE vector operations that are faster than any previously published solution.

  14. Lossless hybridization between photovoltaic and thermoelectric devices.

    PubMed

    Park, Kwang-Tae; Shin, Sun-Mi; Tazebay, Abdullah S; Um, Han-Don; Jung, Jin-Young; Jee, Sang-Won; Oh, Min-Wook; Park, Su-Dong; Yoo, Bongyoung; Yu, Choongho; Lee, Jung-Ho

    2013-01-01

    The optimal hybridization of photovoltaic (PV) and thermoelectric (TE) devices has long been considered ideal for the efficient harnessing solar energy. Our hybrid approach uses full spectrum solar energy via lossless coupling between PV and TE devices while collecting waste energy from thermalization and transmission losses from PV devices. Achieving lossless coupling makes the power output from the hybrid device equal to the sum of the maximum power outputs produced separately from individual PV and TE devices. TE devices need to have low internal resistances enough to convey photo-generated currents without sacrificing the PV fill factor. Concomitantly, a large number of p-n legs are preferred to drive a high Seebeck voltage in TE. Our simple method of attaching a TE device to a PV device has greatly improved the conversion efficiency and power output of the PV device (~30% at a 15°C temperature gradient across a TE device).

  15. Lossless hybridization between photovoltaic and thermoelectric devices

    PubMed Central

    Park, Kwang-Tae; Shin, Sun-Mi; Tazebay, Abdullah S.; Um, Han-Don; Jung, Jin-Young; Jee, Sang-Won; Oh, Min-Wook; Park, Su-Dong; Yoo, Bongyoung; Yu, Choongho; Lee, Jung-Ho

    2013-01-01

    The optimal hybridization of photovoltaic (PV) and thermoelectric (TE) devices has long been considered ideal for the efficient harnessing solar energy. Our hybrid approach uses full spectrum solar energy via lossless coupling between PV and TE devices while collecting waste energy from thermalization and transmission losses from PV devices. Achieving lossless coupling makes the power output from the hybrid device equal to the sum of the maximum power outputs produced separately from individual PV and TE devices. TE devices need to have low internal resistances enough to convey photo-generated currents without sacrificing the PV fill factor. Concomitantly, a large number of p-n legs are preferred to drive a high Seebeck voltage in TE. Our simple method of attaching a TE device to a PV device has greatly improved the conversion efficiency and power output of the PV device (~30% at a 15°C temperature gradient across a TE device). PMID:23820973

  16. Record Conversion at Oregon State.

    ERIC Educational Resources Information Center

    Watkins, Deane

    1985-01-01

    Describes the conversion of card catalog records at William Jasper Kerr Library, Oregon State University, to an online system. Discussion covers the use of OCLC and student assistants, procedures and specifications, and problems associated with massive retrospective conversion needs and uncertain budget allocations. Eight sources are recommended.…

  17. [Neuropsychological assessment in conversion disorder].

    PubMed

    Demır, Süleyman; Çelıkel, Feryal Çam; Taycan, Serap Erdoğan; Etıkan, İlker

    2013-01-01

    Conversion disorder is characterized by functional impairment in motor, sensory, or neurovegetative systems that cannot be explained by a general medical condition. Diagnostic systems emphasize the absence of an organic basis for the dysfunction observed in conversion disorder. Nevertheless, there is a growing body of data on the specific functional brain correlates of conversion symptoms, particularly those obtained via neuroimaging and neurophysiological assessment. The present study aimed to determine if there are differences in measures of cognitive functioning between patients with conversion disorder and healthy controls. The hypothesis of the study was that the patients with conversion disorder would have poorer neurocognitive performance than the controls. The patient group included 43 patients diagnosed as conversion disorder and other psychiatric comorbidities according to DSM-IV-TR. Control group 1 included 44 patients diagnosed with similar psychiatric comorbidities, but not conversion diosorder, and control group 2 included 43 healthy individuals. All participants completed a sociodemographic questionnaire and were administered the SCID-I and a neuropsychological test battery of 6 tests, including the Serial Digit Learning Test (SDLT), Auditory Verbal Learning Test (AVLT), Wechsler Memory Scale, Stroop Color Word Interference Test, Benton Judgment of Line Orientation Test (BJLOT), and Cancellation Test. The patient group had significantly poorer performance on the SDLT, AVLT, Stroop Color Word Interference Test, and BJLOT than both control groups. The present findings highlight the differences between the groups in learning and memory, executive and visuospatial functions, and attention, which seemed to be specific to conversion disorder.

  18. Conversational Competence in Academic Settings

    ERIC Educational Resources Information Center

    Bowman, Richard F.

    2014-01-01

    Conversational competence is a process, not a state. Ithaca does not exist, only the voyage to Ithaca. Vibrant campuses are a series of productive conversations. At its core, communicative competence in academic settings mirrors a collective search for meaning regarding the purpose and direction of a campus community. Communicative competence…

  19. In Conversation with Jim Blair

    ERIC Educational Resources Information Center

    Holman, Andrew

    2012-01-01

    Jim Blair is the only consultant nurse working with people with learning disabilities in the country. His job helps make people better and saves money. This article shares a conversation with Jim Blair. In the conversation, Blair says he is unhappy Valuing People programme did not do as much as it could have done. Jim is worried all the changes,…

  20. Older Siblings as Conversational Partners.

    ERIC Educational Resources Information Center

    Hoff-Ginsberg, Erika; Krueger, Wendy M.

    1991-01-01

    Discusses a study of conversational dyadic interaction between children aged 1.5 to 3 years; their 4-, 5-, 7-, or 8-year-old siblings; and their mothers. Mothers were more supportive conversational partners and adapted their level of speech more than siblings. (GH)

  1. Language Teacher Educators Collaborative Conversations.

    ERIC Educational Resources Information Center

    Bailey, Francis; Hawkins, Maggie; Irujo, Suzanne; Larsen-Freeman, Diane; Rintell, Ellen; Willett, Jerri

    1998-01-01

    Conveys the power and value of collaborative conversation among a small group of language teacher educators who meet regularly to discuss practice. Excerpts from a discussion are presented to show a sample of real issues the teachers face and illustrate how the conversations allow ongoing feedback about real dilemmas from a supportive community of…

  2. Tree value conversion standards revisited

    Treesearch

    Paul S. DeBald; Martin E. Dale; Martin E. Dale

    1991-01-01

    Updated tree value conversion standards (TVCS) are presented for 12 important hardwood species of the oak-hickory forest. These updated standards-developed for each species by butt-log grade, merchantable height, and diameter at breast height-reflect the changes in lumber prices and in conversion costs which have occurred since 1976 when the original TVCS were...

  3. Selecting a Retrospective Conversion Vendor.

    ERIC Educational Resources Information Center

    Lisowski, Andrew; Sessions, Judith

    1984-01-01

    Discussion of using vendors for retrospective conversion of library catalogs rather than in-house projects highlights reasons to consider vendors, four conversion methodologies, and vendor selection criteria (database, non-matches, local data, accuracy, charging, schedule, product delivery time, local system compatibility, MARC format, impact on…

  4. Faculty Meetings: Hidden Conversational Dynamics

    ERIC Educational Resources Information Center

    Bowman, Richard F.

    2015-01-01

    In the everydayness of faculty meetings, collegial conversations mirror distinctive dynamics and practices, which either enhance or undercut organizational effectiveness. A cluster of conversational practices affect how colleagues connect, engage, interact, and influence others during faculty meetings in diverse educational settings. The…

  5. Record Conversion at Oregon State.

    ERIC Educational Resources Information Center

    Watkins, Deane

    1985-01-01

    Describes the conversion of card catalog records at William Jasper Kerr Library, Oregon State University, to an online system. Discussion covers the use of OCLC and student assistants, procedures and specifications, and problems associated with massive retrospective conversion needs and uncertain budget allocations. Eight sources are recommended.…

  6. Selecting a Retrospective Conversion Vendor.

    ERIC Educational Resources Information Center

    Lisowski, Andrew; Sessions, Judith

    1984-01-01

    Discussion of using vendors for retrospective conversion of library catalogs rather than in-house projects highlights reasons to consider vendors, four conversion methodologies, and vendor selection criteria (database, non-matches, local data, accuracy, charging, schedule, product delivery time, local system compatibility, MARC format, impact on…

  7. Conversational Competence in Academic Settings

    ERIC Educational Resources Information Center

    Bowman, Richard F.

    2014-01-01

    Conversational competence is a process, not a state. Ithaca does not exist, only the voyage to Ithaca. Vibrant campuses are a series of productive conversations. At its core, communicative competence in academic settings mirrors a collective search for meaning regarding the purpose and direction of a campus community. Communicative competence…

  8. Conversational Expansion in Young Children.

    ERIC Educational Resources Information Center

    Boynton, Kathleen Reardon; Henke, Lucy L.

    1978-01-01

    The importance of contextual influences to conversational competence development is emphasized. Included are one or more significant adults whose systematic patterns of feedback teach children rules of conversation while providing guided practice in the use of these rules. The role of expansion is examined as one of the common patterns of feedback…

  9. Faculty Meetings: Hidden Conversational Dynamics

    ERIC Educational Resources Information Center

    Bowman, Richard F.

    2015-01-01

    In the everydayness of faculty meetings, collegial conversations mirror distinctive dynamics and practices, which either enhance or undercut organizational effectiveness. A cluster of conversational practices affect how colleagues connect, engage, interact, and influence others during faculty meetings in diverse educational settings. The…

  10. In Conversation with Jim Blair

    ERIC Educational Resources Information Center

    Holman, Andrew

    2012-01-01

    Jim Blair is the only consultant nurse working with people with learning disabilities in the country. His job helps make people better and saves money. This article shares a conversation with Jim Blair. In the conversation, Blair says he is unhappy Valuing People programme did not do as much as it could have done. Jim is worried all the changes,…

  11. Medicinal relationships: caring conversation.

    PubMed

    Mikesell, Lisa

    2013-05-01

    Good social relationships are crucial to well-being and to health in particular. The perception of having supportive social relationships has effects on reducing morbidity and mortality comparable with those of a good diet, regular exercise and cessation of moderate smoking. This suggests that supportive, trusting relationships with doctors could have a substantial direct biomedical effect on patients' health. A critical review of the patient-doctor relationship (PDR) literature is presented, along with a review of relevant interactional studies that examine doctor-patient interactions from the perspective of conversation analysis (CA). This literature shows how patients respond to doctors' verbal and non-verbal behaviours in systematic ways that affect how they disclose and how they relate to doctors. Findings from the CA literature suggest that clinicians might consider several important interactional features to improve the PDR and perhaps also patient health outcomes: (i) the use of open-ended questions (e.g. 'What brought you in today?') and positive polarity items (e.g. 'Is there something else you wanted to talk about today?') elicits patient concerns and addresses unmet concerns more effectively than the use of closed questions and negative polarity items, respectively; (ii) eye gaze suggests availability and an attending recipient, and patients indicate that doctor attentiveness at crucial parts of their problem presentation is important, and (iii) verbal dysfluencies are one practice speakers employ to gain the attention of a non-attending recipient. Doctors may want to pay attention to patients' dysfluencies to better understand when their attention is valued. Constructing supportive relationships with patients often does not require a great investment of time, but it does require commitment to 'being there for patients'. This review suggests that when doctors attune to language and social practices during medical consultations, the relationships they

  12. Shape Memory Composite Hybrid Hinge

    NASA Technical Reports Server (NTRS)

    Fang, Houfei; Im, Eastwood; Lin, John; Scarborough, Stephen

    2012-01-01

    is reduced to below its glass transition temperature. After the deployable structure is launched in space, the SMC tube is reheated and the hinge is unfolded to deploy the structure. Based on test results, the hybrid hinge can achieve higher than 99.999% shape recovery. The hybrid hinge inherits all of the good characteristics of a tape-spring hinge such as simplicity, light weight, high deployment reliability, and high deployment precision. Conversely, it eliminates the deployment impact that has significantly limited the applications of a tape-spring hinge. The deployment dynamics of a hybrid hinge are in a slow and controllable fashion. The SMC tube of a hybrid hinge is a multifunctional component. It serves as a deployment mechanism during the deployment process, and also serves as a structural component after the hinge is fully deployed, which makes a hybrid hinge much stronger and stiffer than a tape-spring hinge. Unlike a mechanically deploying hinge that uses relatively moving components, a hybrid hinge depends on material deformation for its packing and deployment. It naturally eliminates the microdynamic phenomenon.

  13. Advanced Electric Distribution, Switching, and Conversion Technology for Power Control

    NASA Technical Reports Server (NTRS)

    Soltis, James V.

    1998-01-01

    The Electrical Power Control Unit currently under development by Sundstrand Aerospace for use on the Fluids Combustion Facility of the International Space Station is the precursor of modular power distribution and conversion concepts for future spacecraft and aircraft applications. This unit combines modular current-limiting flexible remote power controllers and paralleled power converters into one package. Each unit includes three 1-kW, current-limiting power converter modules designed for a variable-ratio load sharing capability. The flexible remote power controllers can be used in parallel to match load requirements and can be programmed for an initial ON or OFF state on powerup. The unit contains an integral cold plate. The modularity and hybridization of the Electrical Power Control Unit sets the course for future spacecraft electrical power systems, both large and small. In such systems, the basic hybridized converter and flexible remote power controller building blocks could be configured to match power distribution and conversion capabilities to load requirements. In addition, the flexible remote power controllers could be configured in assemblies to feed multiple individual loads and could be used in parallel to meet the specific current requirements of each of those loads. Ultimately, the Electrical Power Control Unit design concept could evolve to a common switch module hybrid, or family of hybrids, for both converter and switchgear applications. By assembling hybrids of a common current rating and voltage class in parallel, researchers could readily adapt these units for multiple applications. The Electrical Power Control Unit concept has the potential to be scaled to larger and smaller ratings for both small and large spacecraft and for aircraft where high-power density, remote power controllers or power converters are required and a common replacement part is desired for multiples of a base current rating.

  14. Scalable hybrid computation with spikes.

    PubMed

    Sarpeshkar, Rahul; O'Halloran, Micah

    2002-09-01

    We outline a hybrid analog-digital scheme for computing with three important features that enable it to scale to systems of large complexity: First, like digital computation, which uses several one-bit precise logical units to collectively compute a precise answer to a computation, the hybrid scheme uses several moderate-precision analog units to collectively compute a precise answer to a computation. Second, frequent discrete signal restoration of the analog information prevents analog noise and offset from degrading the computation. And, third, a state machine enables complex computations to be created using a sequence of elementary computations. A natural choice for implementing this hybrid scheme is one based on spikes because spike-count codes are digital, while spike-time codes are analog. We illustrate how spikes afford easy ways to implement all three components of scalable hybrid computation. First, as an important example of distributed analog computation, we show how spikes can create a distributed modular representation of an analog number by implementing digital carry interactions between spiking analog neurons. Second, we show how signal restoration may be performed by recursive spike-count quantization of spike-time codes. And, third, we use spikes from an analog dynamical system to trigger state transitions in a digital dynamical system, which reconfigures the analog dynamical system using a binary control vector; such feedback interactions between analog and digital dynamical systems create a hybrid state machine (HSM). The HSM extends and expands the concept of a digital finite-state-machine to the hybrid domain. We present experimental data from a two-neuron HSM on a chip that implements error-correcting analog-to-digital conversion with the concurrent use of spike-time and spike-count codes. We also present experimental data from silicon circuits that implement HSM-based pattern recognition using spike-time synchrony. We outline how HSMs may be

  15. Invasion of the hybrids.

    PubMed

    Hegarty, M J

    2012-10-01

    Human activity and climate change are increasingly driving species, which were once separate together, leading to the potential for gene flow. Hybridization between diverged species brings together two genomes which have evolved to meet different adaptive requirements. The unique combination of these traits in a hybrid may be beneficial or maladaptive, but either way it results in increased phenotypic variation. A percentage of hybrid individuals may, therefore, find themselves able to exploit environmental niches which their progenitors cannot, leading to invasive hybrid swarms becoming established in new habitats. Previous research into hybrids, most famously that of Loren Rieseberg and co-workers (Rieseberg et al. 1999, 2003) in sunflowers, demonstrated that hybridization can give rise to transgressive segregation of adaptive traits, wherein the combination of favourable alleles from both parents in hybrids can enable them to outperform either. However, the question still remains as to how much of the competitive ability of hybrids is a direct result of admixture and how much is the result of selection after the fact. In this issue of Molecular Ecology, (Czypionka et al. 2012) describe their study of transcriptional changes resulting from hybridization in a fish hybrid termed invasive sculpins (Cottus). Using gene expression microarray assays, they compare gene expression in both wild and lab-reared invasive hybrids to the progenitor species and experimentally produced F(2) hybrids. They demonstrate that whilst hybridization alone does result in higher variance in gene expression (some of which is transgressive), many of the transgressive changes distinguishing the invasives appear to have come about subsequent to the initial natural hybridization event. They speculate that initial success of the hybrids in their new habitat is facilitated by hybridization, but that optimization of the invasive phenotype and removal of maladaptive traits rapidly reduces the

  16. High performance UV and thermal cure hybrid epoxy adhesive

    NASA Astrophysics Data System (ADS)

    Chen, C. F.; Iwasaki, S.; Kanari, M.; Li, B.; Wang, C.; Lu, D. Q.

    2017-06-01

    New type one component UV and thermal curable hybrid epoxy adhesive was successfully developed. The hybrid epoxy adhesive is complete initiator free composition. Neither photo-initiator nor thermal initiator is contained. The hybrid adhesive is mainly composed of special designed liquid bismaleimide, partially acrylated epoxy resin, acrylic monomer, epoxy resin and latent curing agent. Its UV light and thermal cure behavior was studied by FT-IR spectroscopy and FT-Raman spectroscopy. Adhesive samples cured at UV only, thermal only and UV + thermal cure conditions were investigated. By calculated conversion rate of double bond in both acrylic component and maleimide compound, satisfactory light curability of the hybrid epoxy adhesive was confirmed quantitatively. The investigation results also showed that its UV cure components, acrylic and bismalimide, possess good thermal curability too. The initiator free hybrid epoxy adhesive showed satisfactory UV curability, good thermal curability and high adhesion performance.

  17. Petite fabrique de conversation francaise (Little Factory of French Conversation).

    ERIC Educational Resources Information Center

    Dubroca, Danielle

    1987-01-01

    A technique using dialogues and realistic prose passages from the works of Georges Simenon and Simone de Beauvoir to teach French conversational skills at the college level is explained and illustrated. (MSE)

  18. Petite fabrique de conversation francaise (Little Factory of French Conversation).

    ERIC Educational Resources Information Center

    Dubroca, Danielle

    1987-01-01

    A technique using dialogues and realistic prose passages from the works of Georges Simenon and Simone de Beauvoir to teach French conversational skills at the college level is explained and illustrated. (MSE)

  19. New organic-inorganic hybrid molecular systems and highly organized materials in catalysis

    NASA Astrophysics Data System (ADS)

    Kustov, L. M.

    2015-11-01

    Definitions of hybrid materials are suggested, and applications of these materials are considered. Particular attention is focused on the application of hybrid materials in hydrogenation, partial oxidation, plant biomass conversion, and natural gas reforming, primarily on the use of core-shell nanoparticles and decorated metal nanoparticles in these reactions. Application prospects of various hybrid materials, particularly those of metal-organic frameworks, are discussed.

  20. Roadmap on optical energy conversion

    SciTech Connect

    Boriskina, Svetlana V.; Green, Martin A.; Catchpole, Kylie; Yablonovitch, Eli; Beard, Matthew C.; Okada, Yoshitaka; Lany, Stephan; Gershon, Talia; Zakutayev, Andriy; Tahersima, Mohammad H.; Sorger, Volker J.; Naughton, Michael J.; Kempa, Krzysztof; Dagenais, Mario; Yao, Yuan; Xu, Lu; Sheng, Xing; Bronstein, Noah D.; Rogers, John A.; Alivisatos, A. Paul; Nuzzo, Ralph G.; Gordon, Jeffrey M.; Wu, Di M.; Wisser, Michael D.; Salleo, Alberto; Dionne, Jennifer; Bermel, Peter; Greffet, Jean -Jacques; Celanovic, Ivan; Soljacic, Marin; Manor, Assaf; Rotschild, Carmel; Raman, Aaswath; Zhu, Linxiao; Fan, Shanhui; Chen, Gang

    2016-06-24

    For decades, progress in the field of optical (including solar) energy conversion was dominated by advances in the conventional concentrating optics and materials design. In recent years, however, conceptual and technological breakthroughs in the fields of nanophotonics and plasmonics combined with a better understanding of the thermodynamics of the photon energy-conversion processes reshaped the landscape of energy-conversion schemes and devices. Nanostructured devices and materials that make use of size quantization effects to manipulate photon density of states offer a way to overcome the conventional light absorption limits. Novel optical spectrum splitting and photon-recycling schemes reduce the entropy production in the optical energy-conversion platforms and boost their efficiencies. Optical design concepts are rapidly expanding into the infrared energy band, offering new approaches to harvest waste heat, to reduce the thermal emission losses, and to achieve noncontact radiative cooling of solar cells as well as of optical and electronic circuitries. Light-matter interaction enabled by nanophotonics and plasmonics underlie the performance of the third- and fourth-generation energy-conversion devices, including up- and down-conversion of photon energy, near-field radiative energy transfer, and hot electron generation and harvesting. Finally, the increased market penetration of alternative solar energy-conversion technologies amplifies the role of cost-driven and environmental considerations. This roadmap on optical energy conversion provides a snapshot of the state of the art in optical energy conversion, remaining challenges, and most promising approaches to address these challenges. Leading experts authored 19 focused short sections of the roadmap where they share their vision on a specific aspect of this burgeoning research field. The roadmap opens up with a tutorial section, which introduces major concepts and terminology. As a result, it is our hope that

  1. Roadmap on optical energy conversion

    NASA Astrophysics Data System (ADS)

    Boriskina, Svetlana V.; Green, Martin A.; Catchpole, Kylie; Yablonovitch, Eli; Beard, Matthew C.; Okada, Yoshitaka; Lany, Stephan; Gershon, Talia; Zakutayev, Andriy; Tahersima, Mohammad H.; Sorger, Volker J.; Naughton, Michael J.; Kempa, Krzysztof; Dagenais, Mario; Yao, Yuan; Xu, Lu; Sheng, Xing; Bronstein, Noah D.; Rogers, John A.; Alivisatos, A. Paul; Nuzzo, Ralph G.; Gordon, Jeffrey M.; Wu, Di M.; Wisser, Michael D.; Salleo, Alberto; Dionne, Jennifer; Bermel, Peter; Greffet, Jean-Jacques; Celanovic, Ivan; Soljacic, Marin; Manor, Assaf; Rotschild, Carmel; Raman, Aaswath; Zhu, Linxiao; Fan, Shanhui; Chen, Gang

    2016-07-01

    For decades, progress in the field of optical (including solar) energy conversion was dominated by advances in the conventional concentrating optics and materials design. In recent years, however, conceptual and technological breakthroughs in the fields of nanophotonics and plasmonics combined with a better understanding of the thermodynamics of the photon energy-conversion processes reshaped the landscape of energy-conversion schemes and devices. Nanostructured devices and materials that make use of size quantization effects to manipulate photon density of states offer a way to overcome the conventional light absorption limits. Novel optical spectrum splitting and photon-recycling schemes reduce the entropy production in the optical energy-conversion platforms and boost their efficiencies. Optical design concepts are rapidly expanding into the infrared energy band, offering new approaches to harvest waste heat, to reduce the thermal emission losses, and to achieve noncontact radiative cooling of solar cells as well as of optical and electronic circuitries. Light-matter interaction enabled by nanophotonics and plasmonics underlie the performance of the third- and fourth-generation energy-conversion devices, including up- and down-conversion of photon energy, near-field radiative energy transfer, and hot electron generation and harvesting. Finally, the increased market penetration of alternative solar energy-conversion technologies amplifies the role of cost-driven and environmental considerations. This roadmap on optical energy conversion provides a snapshot of the state of the art in optical energy conversion, remaining challenges, and most promising approaches to address these challenges. Leading experts authored 19 focused short sections of the roadmap where they share their vision on a specific aspect of this burgeoning research field. The roadmap opens up with a tutorial section, which introduces major concepts and terminology. It is our hope that the roadmap

  2. Roadmap on optical energy conversion

    SciTech Connect

    Boriskina, Svetlana V.; Green, Martin A.; Catchpole, Kylie; Yablonovitch, Eli; Beard, Matthew C.; Okada, Yoshitaka; Lany, Stephan; Gershon, Talia; Zakutayev, Andriy; Tahersima, Mohammad H.; Sorger, Volker J.; Naughton, Michael J.; Kempa, Krzysztof; Dagenais, Mario; Yao, Yuan; Xu, Lu; Sheng, Xing; Bronstein, Noah D.; Rogers, John A.; Alivisatos, A. Paul; Nuzzo, Ralph G.; Gordon, Jeffrey M.; Wu, Di M.; Wisser, Michael D.; Salleo, Alberto; Dionne, Jennifer; Bermel, Peter; Greffet, Jean-Jacques; Celanovic, Ivan; Soljacic, Marin; Manor, Assaf; Rotschild, Carmel; Raman, Aaswath; Zhu, Linxiao; Fan, Shanhui; Chen, Gang

    2016-06-24

    For decades, progress in the field of optical (including solar) energy conversion was dominated by advances in the conventional concentrating optics and materials design. In recent years, however, conceptual and technological breakthroughs in the fields of nanophotonics and plasmonics combined with a better understanding of the thermodynamics of the photon energy-conversion processes reshaped the landscape of energy-conversion schemes and devices. Nanostructured devices and materials that make use of size quantization effects to manipulate photon density of states offer a way to overcome the conventional light absorption limits. Novel optical spectrum splitting and photon-recycling schemes reduce the entropy production in the optical energy-conversion platforms and boost their efficiencies. Optical design concepts are rapidly expanding into the infrared energy band, offering new approaches to harvest waste heat, to reduce the thermal emission losses, and to achieve noncontact radiative cooling of solar cells as well as of optical and electronic circuitries. Light-matter interaction enabled by nanophotonics and plasmonics underlie the performance of the third- and fourth-generation energy-conversion devices, including up- and down-conversion of photon energy, near-field radiative energy transfer, and hot electron generation and harvesting. Finally, the increased market penetration of alternative solar energy-conversion technologies amplifies the role of cost-driven and environmental considerations. This roadmap on optical energy conversion provides a snapshot of the state of the art in optical energy conversion, remaining challenges, and most promising approaches to address these challenges. Leading experts authored 19 focused short sections of the roadmap where they share their vision on a specific aspect of this burgeoning research field. The roadmap opens up with a tutorial section, which introduces major concepts and terminology. It is our hope that the roadmap

  3. Roadmap on optical energy conversion

    DOE PAGES

    Boriskina, Svetlana V.; Green, Martin A.; Catchpole, Kylie; ...

    2016-06-24

    For decades, progress in the field of optical (including solar) energy conversion was dominated by advances in the conventional concentrating optics and materials design. In recent years, however, conceptual and technological breakthroughs in the fields of nanophotonics and plasmonics combined with a better understanding of the thermodynamics of the photon energy-conversion processes reshaped the landscape of energy-conversion schemes and devices. Nanostructured devices and materials that make use of size quantization effects to manipulate photon density of states offer a way to overcome the conventional light absorption limits. Novel optical spectrum splitting and photon-recycling schemes reduce the entropy production in themore » optical energy-conversion platforms and boost their efficiencies. Optical design concepts are rapidly expanding into the infrared energy band, offering new approaches to harvest waste heat, to reduce the thermal emission losses, and to achieve noncontact radiative cooling of solar cells as well as of optical and electronic circuitries. Light-matter interaction enabled by nanophotonics and plasmonics underlie the performance of the third- and fourth-generation energy-conversion devices, including up- and down-conversion of photon energy, near-field radiative energy transfer, and hot electron generation and harvesting. Finally, the increased market penetration of alternative solar energy-conversion technologies amplifies the role of cost-driven and environmental considerations. This roadmap on optical energy conversion provides a snapshot of the state of the art in optical energy conversion, remaining challenges, and most promising approaches to address these challenges. Leading experts authored 19 focused short sections of the roadmap where they share their vision on a specific aspect of this burgeoning research field. The roadmap opens up with a tutorial section, which introduces major concepts and terminology. As a result, it is our

  4. From hybrid swarms to swarms of hybrids

    USDA-ARS?s Scientific Manuscript database

    The introgression of modern humans (Homo sapiens) with Neanderthals 40,000 YBP after a half-million years of separation, may have led to the best example of a hybrid swarm on earth. Modern trade and transportation in support of the human hybrids has continued to introduce additional species, genotyp...

  5. Hybrid rocket propulsion

    NASA Technical Reports Server (NTRS)

    Holzman, Allen L.

    1993-01-01

    Topics addressed are: (1) comparison of the theoretical impulses; (2) comparison of the density-specific impulses; (3) general propulsion system features comparison; (4) hybrid systems, booster applications; and (5) hybrid systems, upper stage propulsion applications.

  6. Hydraulic Hybrid Vehicles

    EPA Pesticide Factsheets

    EPA and the United Parcel Service (UPS) have developed a hydraulic hybrid delivery vehicle to explore and demonstrate the environmental benefits of the hydraulic hybrid for urban pick-up and delivery fleets.

  7. Energy conversion and storage program

    NASA Astrophysics Data System (ADS)

    1990-12-01

    The Energy Conversion and Storage Program applies chemical and chemical engineering principles to solve problems in (1) production of new synthetic fuels; (2) development of high-performance rechargeable batteries and fuel cells; (3) development of advanced thermochemical processes for energy storage; (4) characterization of complex chemical processes; and (5) the application of novel materials for energy conversion and transmission. Projects focus on transport-process principles, chemical kinetics, thermodynamics, separation processes, organic and physical chemistry, and advanced methods of analysis. The following five areas are discussed: electrochemical energy storage and conversion; microstructured materials; biotechnology; fossil fuels; and high temperature superconducting processing. Papers have been processed separately for inclusion on the data base.

  8. Mesoscale hybrid calibration artifact

    DOEpatents

    Tran, Hy D.; Claudet, Andre A.; Oliver, Andrew D.

    2010-09-07

    A mesoscale calibration artifact, also called a hybrid artifact, suitable for hybrid dimensional measurement and the method for make the artifact. The hybrid artifact has structural characteristics that make it suitable for dimensional measurement in both vision-based systems and touch-probe-based systems. The hybrid artifact employs the intersection of bulk-micromachined planes to fabricate edges that are sharp to the nanometer level and intersecting planes with crystal-lattice-defined angles.

  9. Hybrid armature projectile

    DOEpatents

    Hawke, Ronald S.; Asay, James R.; Hall, Clint A.; Konrad, Carl H.; Sauve, Gerald L.; Shahinpoor, Mohsen; Susoeff, Allan R.

    1993-01-01

    A projectile for a railgun that uses a hybrid armature and provides a seed block around part of the outer surface of the projectile to seed the hybrid plasma brush. In addition, the hybrid armature is continuously vaporized to replenish plasma in a plasma armature to provide a tandem armature and provides a unique ridge and groove to reduce plasama blowby.

  10. Hybrid quantum information processing

    SciTech Connect

    Furusawa, Akira

    2014-12-04

    I will briefly explain the definition and advantage of hybrid quantum information processing, which is hybridization of qubit and continuous-variable technologies. The final goal would be realization of universal gate sets both for qubit and continuous-variable quantum information processing with the hybrid technologies. For that purpose, qubit teleportation with a continuousvariable teleporter is one of the most important ingredients.

  11. Realizing the Hybrid Library.

    ERIC Educational Resources Information Center

    Pinfield, Stephen; Eaton, Jonathan; Edwards, Catherine; Russell, Rosemary; Wissenburg, Astrid; Wynne, Peter

    1998-01-01

    Outlines five projects currently funded by the United Kingdom's Electronic Libraries Program (eLib): HyLiFe (Hybrid Library of the Future), MALIBU (MAnaging the hybrid Library for the Benefit of Users), HeadLine (Hybrid Electronic Access and Delivery in the Library Networked Environment), ATHENS (authentication scheme), and BUILDER (Birmingham…

  12. Homoploid hybrid expectations

    USDA-ARS?s Scientific Manuscript database

    Homoploid hybrid speciation occurs when a stable, fertile, and reproductively isolated lineage results from hybridization between two distinct species without a change in ploidy level. Reproductive isolation between a homoploid hybrid species and its parents is generally attained via chromosomal re...

  13. Hybrid armature projectile

    DOEpatents

    Hawke, R.S.; Asay, J.R.; Hall, C.A.; Konrad, C.H.; Sauve, G.L.; Shahinpoor, M.; Susoeff, A.R.

    1993-03-02

    A projectile for a railgun that uses a hybrid armature and provides a seed block around part of the outer surface of the projectile to seed the hybrid plasma brush. In addition, the hybrid armature is continuously vaporized to replenish plasma in a plasma armature to provide a tandem armature and provides a unique ridge and groove to reduce plasma blowby.

  14. Intraply Hybrid Composite Design

    NASA Technical Reports Server (NTRS)

    Chamis, C. C.; Sinclair, J. H.

    1986-01-01

    Several theoretical approaches combined in program. Intraply hybrid composites investigated theoretically and experimentally at Lewis Research Center. Theories developed during investigations and corroborated by attendant experiments used to develop computer program identified as INHYD (Intraply Hybrid Composite Design). INHYD includes several composites micromechanics theories, intraply hybrid composite theories, and integrated hygrothermomechanical theory. Equations from theories used by program as appropriate for user's specific applications.

  15. Hybrid rocket instability

    NASA Technical Reports Server (NTRS)

    Greiner, B.; Frederick, R. A., Jr.

    1993-01-01

    The paper provides a brief review of theoretical and experimental studies concerned with hybrid rocket instability. The instabilities discussed include atomization and mixing instabilities, chuffing instabilities, pressure coupled combustion instabilities, and vortex shedding. It is emphasized that the future use of hybrid motor systems as viable design alternatives will depend on a better understanding of hybrid instability.

  16. NASA thermionic-conversion program

    NASA Technical Reports Server (NTRS)

    Morris, J. F.

    1977-01-01

    Technological processes in out-of-core thermionic energy conversion are described. The emphasis was on high temperature electrode materials and system engineering of converter geometries to produce practical power densities.

  17. A Conversation Well Worth Remembering

    ERIC Educational Resources Information Center

    Woolven-Allen, John

    2009-01-01

    To mark the 200th anniversary of Charles Darwin's birth, a special event was held at Oxford, which included a "Conversation" between Professor Richard Dawkins and Bishop Richard Harries. Here we present a personal reminiscence of the event.

  18. Enzymes for improved biomass conversion

    DOEpatents

    Brunecky, Roman; Himmel, Michael E.

    2016-02-02

    Disclosed herein are enzymes and combinations of the enzymes useful for the hydrolysis of cellulose and the conversion of biomass. Methods of degrading cellulose and biomass using enzymes and cocktails of enzymes are also disclosed.

  19. Effective communication during difficult conversations.

    PubMed

    Polito, Jacquelyn M

    2013-06-01

    A strong interest and need exist in the workplace today to master the skills of conducting difficult conversations. Theories and strategies abound, yet none seem to have found the magic formula with universal appeal and success. If it is such an uncomfortable skill to master is it better to avoid or initiate such conversations with employees? Best practices and evidence-based management guide us to the decision that quality improvement dictates effective communication, even when difficult. This brief paper will offer some suggestions for strategies to manage difficult conversations with employees. Mastering the skills of conducting difficult conversations is clearly important to keeping lines of communication open and productive. Successful communication skills may actually help to avert confrontation through employee engagement, commitment and appropriate corresponding behavior

  20. Dynamic Conversion Working Group Summary

    NASA Technical Reports Server (NTRS)

    Chaffee, N.; Sovie, R. J.

    1984-01-01

    The potential of dynamic conversion devices for use in solar and nuclear dynamic space power systems was addressed. Conversion systems considered were based on the use of Brayton, Stirling and Rankine cycles. Both organic and liquid metal Rankine cycles were included. The basic system considerations were: mission requirements, system attributes, system options, technology issues and constraints, and priorities of needed technology development. Mission requirements, where dynamic conversion was considered enabling technology, were identified along with the associated power levels and potential energy sources. When considering the system options special attention was given to recommend operating temperatures and other significant discriminators. A list of prioritized tasks considered important for the successful development of dynamic conversion systems for 1995 and beyond was compiled.

  1. Conversational topics in transsexual persons.

    PubMed

    Van Borsel, John; Cayzeele, Miet; Heirman, Eva; T'sjoen, Guy

    2014-06-01

    Abstract In general, speech language therapy for transsexual persons focuses on pitch and pitch variation and more recently also on resonance. Other communicative aspects are dealt with far less often, especially language. This study investigated to what extent conversational topics might need attention in therapy for transsexual persons. A total of 111 males, 116 females, 28 male-to-female and 18 female-to-male transsexuals were asked to indicate on a list with 34 topics how often they speak about each topic (never, sometimes, often) in conversations with males, with females and in a gender mixed group. Results showed that transsexual persons behave in accordance with the desired gender. However, they also tend to adopt a position depending on the gender of their conversational partner. It can be concluded that in general it is not necessary to pay attention to conversational topics in therapy for transsexual persons.

  2. Virginia Hamilton: Continuing the Conversation.

    ERIC Educational Resources Information Center

    Mikkelsen, Nina

    1995-01-01

    Relates the latest installment of a continuing conversation between the author and Virginia Hamilton. Discusses ethnicity and identity, environmental issues, the creative process, and the way heritage, history, and family storytelling affect a writer's work. (RS)

  3. A Conversation Well Worth Remembering

    ERIC Educational Resources Information Center

    Woolven-Allen, John

    2009-01-01

    To mark the 200th anniversary of Charles Darwin's birth, a special event was held at Oxford, which included a "Conversation" between Professor Richard Dawkins and Bishop Richard Harries. Here we present a personal reminiscence of the event.

  4. Development of Geodetic Conversion Routines

    DTIC Science & Technology

    2001-09-01

    horizontal and vertical datums in the United States. It provides examples to invoke the Dynamic Link Library and use conversion functions in various programming languages, such as Visual Basic , C, and C++.

  5. Quantum frequency conversion with ultra-broadband tuning in a Raman memory

    NASA Astrophysics Data System (ADS)

    Bustard, Philip J.; England, Duncan G.; Heshami, Khabat; Kupchak, Connor; Sussman, Benjamin J.

    2017-05-01

    Quantum frequency conversion is a powerful tool for the construction of hybrid quantum photonic technologies. Raman quantum memories are a promising method of conversion due to their broad bandwidths. Here we demonstrate frequency conversion of THz-bandwidth, fs-duration photons at the single-photon level using a Raman quantum memory based on the rotational levels of hydrogen molecules. We shift photons from 765 nm to wavelengths spanning from 673 to 590 nm—an absolute shift of up to 116 THz. We measure total conversion efficiencies of up to 10% and a maximum signal-to-noise ratio of 4.0(1):1, giving an expected conditional fidelity of 0.75, which exceeds the classical threshold of 2/3. Thermal noise could be eliminated by cooling with liquid nitrogen, giving noiseless conversion with wide tunability in the visible and infrared.

  6. Direct Energy Conversion Literature Abstracts

    DTIC Science & Technology

    1962-12-01

    HOMOPOLAR Apparatus needed to fabricate and test MOTOR , by G. J. Bukow. 46p., Jan. 1961. candidate junction materials and modules (ASD TR-61-101...small homopolar motor as a 3085 component of a thermoelectric energy- NEW TYPE OF THERMOELECTRIC GENER- conversion system, utilizing the low- ATOR...CONVERSION AND HEAT-TRANSFER are silent outboard motors and power FLUIDS FCR SPACE APPLICATIONS, by lawnmiowers. W. D. Weatherford, J.C. Tyler and P. M

  7. Frequency conversion of structured light

    PubMed Central

    Steinlechner, Fabian; Hermosa, Nathaniel; Pruneri, Valerio; Torres, Juan P.

    2016-01-01

    Coherent frequency conversion of structured light, i.e. the ability to manipulate the carrier frequency of a wave front without distorting its spatial phase and intensity profile, provides the opportunity for numerous novel applications in photonic technology and fundamental science. In particular, frequency conversion of spatial modes carrying orbital angular momentum can be exploited in sub-wavelength resolution nano-optics and coherent imaging at a wavelength different from that used to illuminate an object. Moreover, coherent frequency conversion will be crucial for interfacing information stored in the high-dimensional spatial structure of single and entangled photons with various constituents of quantum networks. In this work, we demonstrate frequency conversion of structured light from the near infrared (803 nm) to the visible (527 nm). The conversion scheme is based on sum-frequency generation in a periodically poled lithium niobate crystal pumped with a 1540-nm Gaussian beam. We observe frequency-converted fields that exhibit a high degree of similarity with the input field and verify the coherence of the frequency-conversion process via mode projection measurements with a phase mask and a single-mode fiber. Our results demonstrate the suitability of exploiting the technique for applications in quantum information processing and coherent imaging. PMID:26875448

  8. Frequency conversion of structured light.

    PubMed

    Steinlechner, Fabian; Hermosa, Nathaniel; Pruneri, Valerio; Torres, Juan P

    2016-02-15

    Coherent frequency conversion of structured light, i.e. the ability to manipulate the carrier frequency of a wave front without distorting its spatial phase and intensity profile, provides the opportunity for numerous novel applications in photonic technology and fundamental science. In particular, frequency conversion of spatial modes carrying orbital angular momentum can be exploited in sub-wavelength resolution nano-optics and coherent imaging at a wavelength different from that used to illuminate an object. Moreover, coherent frequency conversion will be crucial for interfacing information stored in the high-dimensional spatial structure of single and entangled photons with various constituents of quantum networks. In this work, we demonstrate frequency conversion of structured light from the near infrared (803 nm) to the visible (527 nm). The conversion scheme is based on sum-frequency generation in a periodically poled lithium niobate crystal pumped with a 1540-nm Gaussian beam. We observe frequency-converted fields that exhibit a high degree of similarity with the input field and verify the coherence of the frequency-conversion process via mode projection measurements with a phase mask and a single-mode fiber. Our results demonstrate the suitability of exploiting the technique for applications in quantum information processing and coherent imaging.

  9. Frequency conversion of structured light

    NASA Astrophysics Data System (ADS)

    Steinlechner, Fabian; Hermosa, Nathaniel; Pruneri, Valerio; Torres, Juan P.

    2016-02-01

    Coherent frequency conversion of structured light, i.e. the ability to manipulate the carrier frequency of a wave front without distorting its spatial phase and intensity profile, provides the opportunity for numerous novel applications in photonic technology and fundamental science. In particular, frequency conversion of spatial modes carrying orbital angular momentum can be exploited in sub-wavelength resolution nano-optics and coherent imaging at a wavelength different from that used to illuminate an object. Moreover, coherent frequency conversion will be crucial for interfacing information stored in the high-dimensional spatial structure of single and entangled photons with various constituents of quantum networks. In this work, we demonstrate frequency conversion of structured light from the near infrared (803 nm) to the visible (527 nm). The conversion scheme is based on sum-frequency generation in a periodically poled lithium niobate crystal pumped with a 1540-nm Gaussian beam. We observe frequency-converted fields that exhibit a high degree of similarity with the input field and verify the coherence of the frequency-conversion process via mode projection measurements with a phase mask and a single-mode fiber. Our results demonstrate the suitability of exploiting the technique for applications in quantum information processing and coherent imaging.

  10. The hydrogen hybrid option

    SciTech Connect

    Smith, J.R.

    1993-10-15

    The energy efficiency of various piston engine options for series hybrid automobiles are compared with conventional, battery powered electric, and proton exchange membrane (PEM) fuel cell hybrid automobiles. Gasoline, compressed natural gas (CNG), and hydrogen are considered for these hybrids. The engine and fuel comparisons are done on a basis of equal vehicle weight, drag, and rolling resistance. The relative emissions of these various fueled vehicle options are also presented. It is concluded that a highly optimized, hydrogen fueled, piston engine, series electric hybrid automobile will have efficiency comparable to a similar fuel cell hybrid automobile and will have fewer total emissions than the battery powered vehicle, even without a catalyst.

  11. Possible involvement of genes on the Q chromosome of Nicotiana tabacum in expression of hybrid lethality and programmed cell death during interspecific hybridization to Nicotiana debneyi.

    PubMed

    Tezuka, Takahiro; Kuboyama, Tsutomu; Matsuda, Toshiaki; Marubashi, Wataru

    2007-08-01

    Hybrid seedlings from the cross between Nicotiana tabacum, an allotetraploid composed of S and T subgenomes, and N. debneyi die at the cotyledonary stage. This lethality involves programmed cell death (PCD). We carried out reciprocal crosses between the two progenitors of N. tabacum, N. sylvestris and N. tomentosiformis, and N. debneyi to reveal whether only the S subgenome in N. tabacum is related to hybrid lethality. Hybrid seedlings from reciprocal crosses between N. sylvestris and N. debneyi showed lethal characteristics identical to those from the cross between N. tabacum and N. debneyi. Conversely, hybrid seedlings from reciprocal crosses between N. tomentosiformis and N. debneyi were viable. Furthermore, hallmarks of PCD were observed in hybrid seedlings from the cross N. debneyi x N. sylvestris, but not in hybrid seedlings from the cross N. debneyi x N. tomentosiformis. We also carried out crosses between monosomic lines of N. tabacum lacking the Q chromosome and N. debneyi. Using Q-chromosome-specific DNA markers, hybrid seedlings were divided into two groups, hybrids possessing the Q chromosome and hybrids lacking the Q chromosome. Hybrids possessing the Q chromosome died with characteristics of PCD. However, hybrids lacking the Q chromosome were viable and PCD did not occur. From these results, we concluded that the Q chromosome belonging to the S subgenome of N. tabacum encodes gene(s) leading to hybrid lethality in the cross N. tabacum x N. debneyi.

  12. Direct hydrogen fuel cell systems for hybrid vehicles

    NASA Astrophysics Data System (ADS)

    Ahluwalia, Rajesh K.; Wang, X.

    Hybridizing a fuel cell system with an energy storage system offers an opportunity to improve the fuel economy of the vehicle through regenerative braking and possibly to increase the specific power and decrease the cost of the combined energy conversion and storage systems. Even in a hybrid configuration it is advantageous to operate the fuel cell system in a load-following mode and use the power from the energy storage system when the fuel cell alone cannot meet the power demand. This paper discusses an approach for designing load-following fuel cell systems for hybrid vehicles and illustrates it by applying it to pressurized, direct hydrogen, polymer-electrolyte fuel cell (PEFC) systems for a mid-size family sedan. The vehicle level requirements relative to traction power, response time, start-up time and energy conversion efficiency are used to select the important parameters for the PEFC stack, air management system, heat rejection system and the water management system.

  13. Nonreciprocal quantum-state conversion between microwave and optical photons

    NASA Astrophysics Data System (ADS)

    Tian, Lin; Li, Zhen

    2017-07-01

    Optoelectromechanical quantum interfaces can be utilized to connect systems with distinctively different frequencies in hybrid quantum networks. Here we present a scheme of nonreciprocal quantum-state conversion between microwave and optical photons via an optoelectromechanical interface. By introducing an auxiliary cavity and manipulating the phase differences between the linearized light-matter couplings, unidirectional state transmission that is immune to mechanical noise can be achieved. This interface can function as an isolator, a circulator, and a two-way switch that routes the input state to a designated output channel. We show that under a generalized impedance matching condition the state conversion can prevent thermal fluctuations of the mechanical mode from propagating to the cavity outputs and reach high fidelity. The realization of this scheme is also discussed.

  14. Thermoelectric Energy Conversion: Future Directions and Technology Development Needs

    NASA Technical Reports Server (NTRS)

    Fleurial, Jean-Pierre

    2007-01-01

    This viewgraph presentation reviews the process of thermoelectric energy conversion along with key technology needs and challenges. The topics include: 1) The Case for Thermoelectrics; 2) Advances in Thermoelectrics: Investment Needed; 3) Current U.S. Investment (FY07); 4) Increasing Thermoelectric Materials Conversion Efficiency Key Science Needs and Challenges; 5) Developing Advanced TE Components & Systems Key Technology Needs and Challenges; 6) Thermoelectrics; 7) 200W Class Lightweight Portable Thermoelectric Generator; 8) Hybrid Absorption Cooling/TE Power Cogeneration System; 9) Major Opportunities in Energy Industry; 10) Automobile Waste Heat Recovery; 11) Thermoelectrics at JPL; 12) Recent Advances at JPL in Thermoelectric Converter Component Technologies; 13) Thermoelectrics Background on Power Generation and Cooling Operational Modes; 14) Thermoelectric Power Generation; and 15) Thermoelectric Cooling.

  15. Mode Conversion Heating Scenarios for the National Compact Stellarator Experiment

    SciTech Connect

    Majeski, R.; Wilson, J.R.; and Zarnstorff, M.

    2001-05-18

    Radio-frequency heating scenarios for the National Compact Stellarator eXperiment (NCSX) are considered. The focus here is on mode conversion from the fast to the slow ion Bernstein wave as either an electron or ''bulk'' ion heating technique, using a high-field side launch to directly access the ion-ion hybrid layer. Modeling for the planned parameters of NCSX [R(subscript ave) {approximately} 1.4 m, a(subscript ave) {approximately} 0.4 m, B(subscript T)(0) {approximately} 1.2-2 T, n(subscript e)(0) {approximately} 2-5 x 10(superscript19) m(superscript -3), T(subscript e)(0) {approximately} T(subscript i)(0) {approximately} 1-2 keV] for mode conversion in D-H and D-3He plasmas is presented. Possible types of high-field side antennas are also briefly discussed.

  16. Highly efficient frequency conversion with bandwidth compression of quantum light

    NASA Astrophysics Data System (ADS)

    Allgaier, Markus; Ansari, Vahid; Sansoni, Linda; Eigner, Christof; Quiring, Viktor; Ricken, Raimund; Harder, Georg; Brecht, Benjamin; Silberhorn, Christine

    2017-01-01

    Hybrid quantum networks rely on efficient interfacing of dissimilar quantum nodes, as elements based on parametric downconversion sources, quantum dots, colour centres or atoms are fundamentally different in their frequencies and bandwidths. Although pulse manipulation has been demonstrated in very different systems, to date no interface exists that provides both an efficient bandwidth compression and a substantial frequency translation at the same time. Here we demonstrate an engineered sum-frequency-conversion process in lithium niobate that achieves both goals. We convert pure photons at telecom wavelengths to the visible range while compressing the bandwidth by a factor of 7.47 under preservation of non-classical photon-number statistics. We achieve internal conversion efficiencies of 61.5%, significantly outperforming spectral filtering for bandwidth compression. Our system thus makes the connection between previously incompatible quantum systems as a step towards usable quantum networks.

  17. Highly efficient frequency conversion with bandwidth compression of quantum light

    PubMed Central

    Allgaier, Markus; Ansari, Vahid; Sansoni, Linda; Eigner, Christof; Quiring, Viktor; Ricken, Raimund; Harder, Georg; Brecht, Benjamin; Silberhorn, Christine

    2017-01-01

    Hybrid quantum networks rely on efficient interfacing of dissimilar quantum nodes, as elements based on parametric downconversion sources, quantum dots, colour centres or atoms are fundamentally different in their frequencies and bandwidths. Although pulse manipulation has been demonstrated in very different systems, to date no interface exists that provides both an efficient bandwidth compression and a substantial frequency translation at the same time. Here we demonstrate an engineered sum-frequency-conversion process in lithium niobate that achieves both goals. We convert pure photons at telecom wavelengths to the visible range while compressing the bandwidth by a factor of 7.47 under preservation of non-classical photon-number statistics. We achieve internal conversion efficiencies of 61.5%, significantly outperforming spectral filtering for bandwidth compression. Our system thus makes the connection between previously incompatible quantum systems as a step towards usable quantum networks. PMID:28134242

  18. Thermoelectric Energy Conversion: Future Directions and Technology Development Needs

    NASA Technical Reports Server (NTRS)

    Fleurial, Jean-Pierre

    2007-01-01

    This viewgraph presentation reviews the process of thermoelectric energy conversion along with key technology needs and challenges. The topics include: 1) The Case for Thermoelectrics; 2) Advances in Thermoelectrics: Investment Needed; 3) Current U.S. Investment (FY07); 4) Increasing Thermoelectric Materials Conversion Efficiency Key Science Needs and Challenges; 5) Developing Advanced TE Components & Systems Key Technology Needs and Challenges; 6) Thermoelectrics; 7) 200W Class Lightweight Portable Thermoelectric Generator; 8) Hybrid Absorption Cooling/TE Power Cogeneration System; 9) Major Opportunities in Energy Industry; 10) Automobile Waste Heat Recovery; 11) Thermoelectrics at JPL; 12) Recent Advances at JPL in Thermoelectric Converter Component Technologies; 13) Thermoelectrics Background on Power Generation and Cooling Operational Modes; 14) Thermoelectric Power Generation; and 15) Thermoelectric Cooling.

  19. Serious Illness Conversations in ESRD.

    PubMed

    Mandel, Ernest I; Bernacki, Rachelle E; Block, Susan D

    2016-12-28

    Dialysis-dependent ESRD is a serious illness with high disease burden, morbidity, and mortality. Mortality in the first year on dialysis for individuals over age 75 years old approaches 40%, and even those with better prognoses face multiple hospitalizations and declining functional status. In the last month of life, patients on dialysis over age 65 years old experience higher rates of hospitalization, intensive care unit admission, procedures, and death in hospital than patients with cancer or heart failure, while using hospice services less. This high intensity of care is often inconsistent with the wishes of patients on dialysis but persists due to failure to explore or discuss patient goals, values, and preferences in the context of their serious illness. Fewer than 10% of patients on dialysis report having had a conversation about goals, values, and preferences with their nephrologist, although nearly 90% report wanting this conversation. Many nephrologists shy away from these conversations, because they do not wish to upset their patients, feel that there is too much uncertainty in their ability to predict prognosis, are insecure in their skills at broaching the topic, or have difficulty incorporating the conversations into their clinical workflow. In multiple studies, timely discussions about serious illness care goals, however, have been associated with enhanced goal-consistent care, improved quality of life, and positive family outcomes without an increase in patient distress or anxiety. In this special feature article, we will (1) identify the barriers to serious illness conversations in the dialysis population, (2) review best practices in and specific approaches to conducting serious illness conversations, and (3) offer solutions to overcome barriers as well as practical advice, including specific language and tools, to implement serious illness conversations in the dialysis population.

  20. Hybrid thermionic-photovoltaic converter

    SciTech Connect

    Datas, A.

    2016-04-04

    A conceptual device for the direct conversion of heat into electricity is presented. This concept hybridizes thermionic (TI) and thermophotovoltaic (TPV) energy conversion in a single thermionic-photovoltaic (TIPV) solid-state device. This device transforms into electricity both the electron and photon fluxes emitted by an incandescent surface. This letter presents an idealized analysis of this device in order to determine its theoretical potential. According to this analysis, the key advantage of this converter, with respect to either TPV or TI, is the higher power density in an extended temperature range. For low temperatures, TIPV performs like TPV due to the negligible electron flux. On the contrary, for high temperatures, TIPV performs like TI due to the great enhancement of the electron flux, which overshadows the photon flux contribution. At the intermediate temperatures, ∼1650 K in the case of this particular study, I show that the power density potential of TIPV converter is twice as great as that of TPV and TI. The greatest impact concerns applications in which the temperature varies in a relatively wide range, for which averaged power density enhancement above 500% is attainable.

  1. Polarized gene conversion at the bz locus of maize.

    PubMed

    Dooner, Hugo K; He, Limei

    2014-09-23

    Nucleotide diversity is greater in maize than in most organisms studied to date, so allelic pairs in a hybrid tend to be highly polymorphic. Most recombination events between such pairs of maize polymorphic alleles are crossovers. However, intragenic recombination events not associated with flanking marker exchange, corresponding to noncrossover gene conversions, predominate between alleles derived from the same progenitor. In these dimorphic heterozygotes, the two alleles differ only at the two mutant sites between which recombination is being measured. To investigate whether gene conversion at the bz locus is polarized, two large diallel crossing matrices involving mutant sites spread across the bz gene were performed and more than 2,500 intragenic recombinants were scored. In both diallels, around 90% of recombinants could be accounted for by gene conversion. Furthermore, conversion exhibited a striking polarity, with sites located within 150 bp of the start and stop codons converting more frequently than sites located in the middle of the gene. The implications of these findings are discussed with reference to recent data from genome-wide studies in other plants.

  2. Energy Conversion and Storage Program

    NASA Astrophysics Data System (ADS)

    Cairns, E. J.

    1993-06-01

    This report is the 1992 annual progress report for the Energy Conversion and Storage Program, a part of the Energy and Environment Division of the Lawrence Berkeley Laboratory. Work described falls into three broad areas: electrochemistry; chemical applications; and materials applications. The Energy Conversion and Storage Program applies principles of chemistry and materials science to solve problems in several areas: (1) production of new synthetic fuels, (2) development of high-performance rechargeable batteries and fuel cells, (3) development of advanced thermochemical processes for energy conversion, (4) characterization of complex chemical processes and chemical species, and (5) study and application of novel materials for energy conversion and transmission. Projects focus on transport-process principles, chemical kinetics, thermodynamics, separation processes, organic and physical chemistry, novel materials, and advanced methods of analysis. Electrochemistry research aims to develop advanced power systems for electric vehicle and stationary energy storage applications. Chemical applications research includes topics such as separations, catalysis, fuels, and chemical analyses. Included in this program area are projects to develop improved, energy-efficient methods for processing product and waste streams from synfuel plants, coal gasifiers, and biomass conversion processes. Materials applications research includes evaluation of the properties of advanced materials, as well as development of novel preparation techniques. For example, techniques such as sputtering, laser ablation, and poised laser deposition are being used to produce high-temperature superconducting films.

  3. The ethics of conversion therapy.

    PubMed

    Murphy, Timothy F

    1991-04-01

    ... Both the past and present have seen a number of methods being used to extinguish homoerotic desire and behavior and to inaugurate heteroeroticism in their place, methods I will here call conversion therapies... The typical defense of such therapy holds that even if homoeroticism is not necessarily a disease or evil, neither is it a universal good... Conversion therapy is morally defensible, on such a view, because some people suffer from the perceived consequences of homoerotic orientations despite the freedom and toleration extended to gay men and lesbians in certain areas... Against the view that conversion therapy is morally defensible as a matter of personal preference, I here argue that such therapy is morally suspect and should be resisted for a number of reasons....

  4. Asymptotic cost in document conversion

    NASA Astrophysics Data System (ADS)

    Blostein, Dorothea; Nagy, George

    2012-01-01

    In spite of a hundredfold decrease in the cost of relevant technologies, the role of document image processing systems is gradually declining due to the transition to an on-line world. Nevertheless, in some high-volume applications, document image processing software still saves millions of dollars by accelerating workflow, and similarly large savings could be realized by more effective automation of the multitude of low-volume personal document conversions. While potential cost savings, based on estimates of costs and values, are a driving force for new developments, quantifying such savings is difficult. The most important trend is that the cost of computing resources for DIA is becoming insignificant compared to the associated labor costs. An econometric treatment of document processing complements traditional performance evaluation, which focuses on assessing the correctness of the results produced by document conversion software. Researchers should look beyond the error rate for advancing both production and personal document conversion.

  5. Mode conversion experiments in TFTR

    NASA Astrophysics Data System (ADS)

    Majeski, R.; Hosea, J. C.; Phillips, C. K.; Rogers, J. H.; Schilling, G.; Wilson, J. R.; Batha, S.; Darrow, D.; Fisch, N. J.; Herrmann, M. C.; Ignat, D.; Levinton, F.; Mazzucato, E.; Murakami, M.; Nazikian, R.; Rasmussen, D.; Valeo, E. J.

    1996-02-01

    In the Tokamak Fusion Test Reactor (TFTR) the mode converted ion Bernstein wave (IBW) has been shown to heat electrons, drive current (both on and off axis), and to interact with fusion products. D-3He and D-T-3He plasmas have been used as mode conversion targets. On-axis mode conversion heating increased Te(0) from 3 keV to 10 keV with 4 MW of ICRF. On-axis currents of 125 kA with 2 MW of ICRF, and off axis currents of 100 kA with 4 MW of ICRF, have been driven. A strong interaction of the IBW with fusion products has been observed. Mode conversion current drive (MCCD) for TPX is briefly discussed.

  6. Conversations with Environmental Educators: A Conversation with Four Classroom Teachers

    ERIC Educational Resources Information Center

    Volk, Trudi L.

    2003-01-01

    This article includes a conversation with four environmental education classroom teachers. The author introduces the four classroom teachers, Marie Marrs, Barb Pietrucha, Vicki Newberry, and Dara Lukonen. In the interview, the four environmental education classroom teachers describe the environmental education in their classrooms. Three of these…

  7. Des documents authentiques pour la conversation (Authentic Documents for Conversation)

    ERIC Educational Resources Information Center

    Mariet, Jacqueline

    1978-01-01

    A description of two conversation courses (elementary and advanced) given during a summer session at Middlebury College. The materials used were tapes and slides made in France by the instructors to realize the course objectives--use of authentic spoken French and cultural education. (Text is in French.) (AMH)

  8. Conversations with Environmental Educators: A Conversation with Four Classroom Teachers

    ERIC Educational Resources Information Center

    Volk, Trudi L.

    2003-01-01

    This article includes a conversation with four environmental education classroom teachers. The author introduces the four classroom teachers, Marie Marrs, Barb Pietrucha, Vicki Newberry, and Dara Lukonen. In the interview, the four environmental education classroom teachers describe the environmental education in their classrooms. Three of these…

  9. La Conversation par le theatre (Conversation through Theater).

    ERIC Educational Resources Information Center

    Bayoff, Marie-Jose

    1986-01-01

    A successful advanced college-level French conversation course using French theater as a basis for students to learn oral skills has six phases: an overview of the history of French theater, reading, adaptation of the text, rehearsal-readings, final rehearsals, and performance. (MSE)

  10. Pronunciation models for conversational speech

    NASA Astrophysics Data System (ADS)

    Johnson, Keith

    2005-09-01

    Using a pronunciation dictionary of clear speech citation forms a segment deletion rate of nearly 12% is found in a corpus of conversational speech. The number of apparent segment deletions can be reduced by constructing a pronunciation dictionary that records one or more of the actual pronunciations found in conversational speech; however, the resulting empirical pronunciation dictionary often fails to include the citation pronunciation form. Issues involved in selecting pronunciations for a dictionary for linguistic, psycholinguistic, and ASR research will be discussed. One conclusion is that Ladefoged may have been the wiser for avoiding the business of producing pronunciation dictionaries. [Supported by NIDCD Grant No. R01 DC04330-03.

  11. Recirculation in multiple wave conversions

    SciTech Connect

    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.

  12. Power conversion in electrical networks

    NASA Technical Reports Server (NTRS)

    Wood, J. R.

    1974-01-01

    Aspects of dc to dc conversion were studied in terms of a class of switching voltage regulators from a stability viewpoint. Background concepts of nonlinear system theory were considered, including the problem of obtaining suitable realizations for a class of positive operators. It is shown that the state evolution equations for a power conversion network are in general of bilinear form, and that the theory of lie groups and lie algebras is useful in analyzing such systems. The feedback stabilization of a class of bilinear systems whose state space is a manifold is also discussed.

  13. [Hydroxylamine conversion by anammox enrichment].

    PubMed

    Hu, Anhui; Zheng, Ping; Lu, Huifeng; Ding, Shuang; Wang, Caihua

    2010-04-01

    Hydroxylamine is an important intermediate product of anammox. This study was focused on the characteristics of hydroxylamine and nitrite conversions by anammox enrichment. The changes of nitrogenous substrates and related products with time were measured using batch tests with anammox enrichment as inoculum. Since hydroxylamine didn't react with nitrite in uninoculated control culture, these two compounds were chemically stable. Both of them decreased with time in anammox enrichment inoculated cultures, in which ammonia as intermediate product would be produced and converted with the maximum concentration being 0.338 mg/L. The total nitrogen concentration decreased from 4.694 mmol/L to 0.812 mmol/L with conversion rate 82.7% in the end. When hydroxylamine and nitrite concentrations were about 2.5 mmol/L respectively, the maximum specific sludge conversion rates of hydroxylamine was 0.535 mmol/(gVSS.h), which was 1.81 times bigger than that of ammonia in ammonia reaction system; the maximum specific sludge rate of total nitrogen was slightly higher than that in ammonia reaction system. When hydroxylamine concentration increased to 5.0 mmol/L, the hydroxylamine and nitrite conversion rates promoted by 26.7% and 120.7% respectively; and the maximum ammonia accumulated was 1.810 mmol/L. When nitrite concentration increased to 5.0 mmol/L, the hydroxylamine and nitrite conversion rates promoted by 6.9% and 9.0% respectively; and the maximum ammonia accumulated was 0.795 mmol/L. Anammox enrichment was capable of converting hydroxylamine and nitrite simultaneously and had the higher conversion rate of hydroxylamine than ammonia conversion rate. Hydroxylamine and nitrite conversion rates were less affected by increase in nitrite concentration, but more significantly influenced by increase in hydroxylamine. The maximum ammonia concentration accumulated would rise as the result of increasing both hydroxylamine and nitrite. The result of experiment was consistent with pathway

  14. Review of betavoltaic energy conversion

    NASA Technical Reports Server (NTRS)

    Olsen, Larry C.

    1993-01-01

    Betavoltaic energy conversion refers to the generation of power by coupling a beta source to a semiconductor junction device. The theory of betavoltaic energy conversion and some past studies of the subject are briefly reviewed. Calculations of limiting efficiencies for semiconductor cells versus bandgap are presented along with specific studies for Pm-147 and Ni-63 fueled devices. The approach used for fabricating Pm-147 fueled batteries by the author in the early 1970's is reviewed. Finally, the potential performance of advanced betavoltaic power sources is considered.

  15. Hybrid radiator cooling system

    DOEpatents

    France, David M.; Smith, David S.; Yu, Wenhua; Routbort, Jules L.

    2016-03-15

    A method and hybrid radiator-cooling apparatus for implementing enhanced radiator-cooling are provided. The hybrid radiator-cooling apparatus includes an air-side finned surface for air cooling; an elongated vertically extending surface extending outwardly from the air-side finned surface on a downstream air-side of the hybrid radiator; and a water supply for selectively providing evaporative cooling with water flow by gravity on the elongated vertically extending surface.

  16. Military Hybrid Vehicle Survey

    DTIC Science & Technology

    2011-08-03

    Some examples include:  Allison Hybrid EP System™ - Transit buses two-mode parallel hybrid with continuously variable transmission (CVT)  Azure... Transit Buses , Proceeding of the Vehicular Technology Conference, Vol. 5, pp 3310-3315, October 2003. [3] E. Rosenthal, U.S. Military Orders Less...applications such as delivery trucks and transit busses. One of the biggest justifications for hybrids is their fuel efficiency. However, the U.S

  17. 16 CFR 1012.7 - Telephone conversations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Telephone conversations. 1012.7 Section 1012... AGENCY PERSONNEL AND OUTSIDE PARTIES § 1012.7 Telephone conversations. (a) Telephone conversations... meet with Agency employees. However, because telephone conversations, by their very nature, are...

  18. 16 CFR 1012.7 - Telephone conversations.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Telephone conversations. 1012.7 Section 1012... AGENCY PERSONNEL AND OUTSIDE PARTIES § 1012.7 Telephone conversations. (a) Telephone conversations... meet with Agency employees. However, because telephone conversations, by their very nature, are...

  19. 16 CFR 1012.7 - Telephone conversations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Telephone conversations. 1012.7 Section 1012... AGENCY PERSONNEL AND OUTSIDE PARTIES § 1012.7 Telephone conversations. (a) Telephone conversations... meet with Agency employees. However, because telephone conversations, by their very nature, are...

  20. 16 CFR 1012.7 - Telephone conversations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Telephone conversations. 1012.7 Section 1012... AGENCY PERSONNEL AND OUTSIDE PARTIES § 1012.7 Telephone conversations. (a) Telephone conversations... meet with Agency employees. However, because telephone conversations, by their very nature, are...

  1. 16 CFR 1012.7 - Telephone conversations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 2 2014-01-01 2014-01-01 false Telephone conversations. 1012.7 Section 1012... AGENCY PERSONNEL AND OUTSIDE PARTIES § 1012.7 Telephone conversations. (a) Telephone conversations... meet with Agency employees. However, because telephone conversations, by their very nature, are...

  2. Calculation Methods and Conversions for Pesticide Application.

    ERIC Educational Resources Information Center

    Cole, Herbert, Jr.

    This agriculture extension service publication from Pennsylvania State University consists of conversion tables and formulas for determining concentration and rate of application of pesticides. Contents include: (1) Area and volume conversions; (2) Important conversion formulae; (3) Conversions for rates of application; (4) Quantities of pesticide…

  3. Calculation Methods and Conversions for Pesticide Application.

    ERIC Educational Resources Information Center

    Cole, Herbert, Jr.

    This agriculture extension service publication from Pennsylvania State University consists of conversion tables and formulas for determining concentration and rate of application of pesticides. Contents include: (1) Area and volume conversions; (2) Important conversion formulae; (3) Conversions for rates of application; (4) Quantities of pesticide…

  4. Si/PEDOT:PSS core/shell nanowire arrays for efficient hybrid solar cells.

    PubMed

    Lu, Wenhui; Wang, Chengwei; Yue, Wei; Chen, Liwei

    2011-09-01

    A solution filling and drying method has been demonstrated to fabricate Si/PEDOT:PSS core/shell nanowire arrays for hybrid solar cells. The hybrid core/shell nanowire arrays show excellent broadband anti-reflection, and resulting hybrid solar cells absorb about 88% of AM 1.5G photons in the 300-1100 nm range. The power conversion efficiency (PCE) of the hybrid solar cell reaches 6.35%, and is primarily limited by direct and indirect interfacial recombination of charge carriers.

  5. Managing hybrid marketing systems.

    PubMed

    Moriarty, R T; Moran, U

    1990-01-01

    As competition increases and costs become critical, companies that once went to market only one way are adding new channels and using new methods - creating hybrid marketing systems. These hybrid marketing systems hold the promise of greater coverage and reduced costs. But they are also hard to manage; they inevitably raise questions of conflict and control: conflict because marketing units compete for customers; control because new indirect channels are less subject to management authority. Hard as they are to manage, however, hybrid marketing systems promise to become the dominant design, replacing the "purebred" channel strategy in all kinds of businesses. The trick to managing the hybrid is to analyze tasks and channels within and across a marketing system. A map - the hybrid grid - can help managers make sense of their hybrid system. What the chart reveals is that channels are not the basic building blocks of a marketing system; marketing tasks are. The hybrid grid forces managers to consider various combinations of channels and tasks that will optimize both cost and coverage. Managing conflict is also an important element of a successful hybrid system. Managers should first acknowledge the inevitability of conflict. Then they should move to bound it by creating guidelines that spell out which customers to serve through which methods. Finally, a marketing and sales productivity (MSP) system, consisting of a central marketing database, can act as the central nervous system of a hybrid marketing system, helping managers create customized channels and service for specific customer segments.

  6. Recognition of the unique structure of DNA:RNA hybrids.

    PubMed

    Shaw, Nicholas N; Arya, Dev P

    2008-07-01

    Targeting nucleic acids using small molecules routinely uses the end products in the conversion pathway of "DNA to RNA, RNA to protein". However, the intermediate processes in this path have not always been targeted. The DNA-RNA interaction, specifically DNA:RNA hybrid formation, provides a unique target for controlling the transfer of genetic information through binding by small molecules. Not only do DNA:RNA hybrids differ in conformation from widely targeted DNA and RNA, the low occurrence within biological systems further validates their therapeutic potential. Surprisingly, a survey of the literature reveals only a handful of ligands that bind DNA:RNA hybrids; in comparison, the number of ligands designed to target DNA is in the thousands. DNA:RNA hybrids, from their scientific inception to current applications in ligand targeting, are discussed.

  7. DOE/EPRI hybrid power system

    SciTech Connect

    Stiger, S.G.; Taylor, K.J.; Hughes, E.E.

    1988-01-01

    One of the primary objectives of the DOE Geopressured Geothermal Program is to improve methods for optimum energy extraction from geopressured reservoirs. Hybrid power systems which take advantage of the chemical and thermal energy content of geopressured fluids could improve conversion efficiency by 15 to 20% over the same amount of fuel and geothermal fluid processed separately. In a joint DOE/EPRI effort, equipment from the Direct Contact heat Exchange test facility at East Mesa is being modified for use in a unique geopressured hybrid power plant located at the Pleasant Bayou wellsite in Brazoria County, TX. Natural gas separated at the wellhead will fuel a gas turbine, and exhaust heat from the engine will be used with the geothermal brine to vaporize isobutane in a binary power cycle. The hybrid power system is designed for 10,000 bbl/day brine flow, with estimated power production of 980 kW (net). In addition to evaluating the enhanced performance resulting from the combined power generation cycles, operation of the hybrid unit will provide a demonstration of fuel flexibility in an individual plant. This approach would allow a resource developer to reduce costs and risks by optimizing production for various economic climates and would improve the mix in a utility's generating system. 5 refs., 2 figs.

  8. From hybrid swarms to swarms of hybrids

    USGS Publications Warehouse

    Stohlgren, Thomas J.; Szalanski, Allen L; Gaskin, John F.; Young, Nicholas E.; West, Amanda; Jarnevich, Catherine S.; Tripodi, Amber

    2014-01-01

    Science has shown that the introgression or hybridization of modern humans (Homo sapiens) with Neanderthals up to 40,000 YBP may have led to the swarm of modern humans on earth. However, there is little doubt that modern trade and transportation in support of the humans has continued to introduce additional species, genotypes, and hybrids to every country on the globe. We assessed the utility of species distributions modeling of genotypes to assess the risk of current and future invaders. We evaluated 93 locations of the genus Tamarix for which genetic data were available. Maxent models of habitat suitability showed that the hybrid, T. ramosissima x T. chinensis, was slightly greater than the parent taxa (AUCs > 0.83). General linear models of Africanized honey bees, a hybrid cross of Tanzanian Apis mellifera scutellata and a variety of European honey bee including A. m. ligustica, showed that the Africanized bees (AUC = 0.81) may be displacing European honey bees (AUC > 0.76) over large areas of the southwestern U.S. More important, Maxent modeling of sub-populations (A1 and A26 mitotypes based on mDNA) could be accurately modeled (AUC > 0.9), and they responded differently to environmental drivers. This suggests that rapid evolutionary change may be underway in the Africanized bees, allowing the bees to spread into new areas and extending their total range. Protecting native species and ecosystems may benefit from risk maps of harmful invasive species, hybrids, and genotypes.

  9. Energy Conversion and Storage Program

    SciTech Connect

    Cairns, E.J.

    1992-03-01

    The Energy Conversion and Storage Program applies chemistry and materials science principles to solve problems in (1) production of new synthetic fuels, (2) development of high-performance rechargeable batteries and fuel cells, (3) development of advanced thermochemical processes for energy conversion, (4) characterization of complex chemical processes, and (5) application of novel materials for energy conversion and transmission. Projects focus on transport-process principles, chemical kinetics, thermodynamics, separation processes, organic and physical chemistry, novel materials, and advanced methods of analysis. Electrochemistry research aims to develop advanced power systems for electric vehicle and stationary energy storage applications. Topics include identification of new electrochemical couples for advanced rechargeable batteries, improvements in battery and fuel-cell materials, and the establishment of engineering principles applicable to electrochemical energy storage and conversion. Chemical Applications research includes topics such as separations, catalysis, fuels, and chemical analyses. Included in this program area are projects to develop improved, energy-efficient methods for processing waste streams from synfuel plants and coal gasifiers. Other research projects seek to identify and characterize the constituents of liquid fuel-system streams and to devise energy-efficient means for their separation. Materials Applications research includes the evaluation of the properties of advanced materials, as well as the development of novel preparation techniques. For example, the use of advanced techniques, such as sputtering and laser ablation, are being used to produce high-temperature superconducting films.

  10. Coaching Conversations: Enacting Instructional Scaffolding

    ERIC Educational Resources Information Center

    Gibson, Sharan A.

    2011-01-01

    This study analyzed coaching conversations and interviews of four coach/teacher partnerships for specific ways in which kindergarten and first-grade teachers, and coaches, conceptualized instructional scaffolding for guided reading. Interview transcripts were coded for coaches' and teachers' specific hypotheses/ ideas regarding instructional…

  11. Technology for satellite power conversion

    NASA Technical Reports Server (NTRS)

    Campbell, D. P.; Gouker, M. A.; Summers, C.; Gallagher, J. J.

    1984-01-01

    Techniques for satellite electromagnetic energy transfer and power conversion at millimeter and infrared wavelengths are discussed. The design requirements for rectenna receiving elements are reviewed for both coherent radiation sources and Earth thermal infrared emission. Potential power transmitters including gyrotrons, free electron lasers, and CO2 lasers are assessed along with the rectification properties of metal-oxide metal diode power converters.

  12. Conversion events in gene clusters

    PubMed Central

    2011-01-01

    Background Gene clusters containing multiple similar genomic regions in close proximity are of great interest for biomedical studies because of their associations with inherited diseases. However, such regions are difficult to analyze due to their structural complexity and their complicated evolutionary histories, reflecting a variety of large-scale mutational events. In particular, conversion events can mislead inferences about the relationships among these regions, as traced by traditional methods such as construction of phylogenetic trees or multi-species alignments. Results To correct the distorted information generated by such methods, we have developed an automated pipeline called CHAP (Cluster History Analysis Package) for detecting conversion events. We used this pipeline to analyze the conversion events that affected two well-studied gene clusters (α-globin and β-globin) and three gene clusters for which comparative sequence data were generated from seven primate species: CCL (chemokine ligand), IFN (interferon), and CYP2abf (part of cytochrome P450 family 2). CHAP is freely available at http://www.bx.psu.edu/miller_lab. Conclusions These studies reveal the value of characterizing conversion events in the context of studying gene clusters in complex genomes. PMID:21798034

  13. Conversation at the Intermediate Level

    ERIC Educational Resources Information Center

    Dunlop, Ian

    1975-01-01

    Discusses the use of free conversation, especially with regard to vocabulary. Recommends group discussion in the FL, using, at the intermediate level, limited, familiar vocabulary. At a higher level, words from a special technical vocabulary may be introduced, aurally and visually. A teaching example ("Traffic") is given with thorough…

  14. Semester Conversion. 1983 Implementation Guide.

    ERIC Educational Resources Information Center

    Atlanta Public Schools, GA.

    This update is designed to provide information on the conversion in the Atlanta public school system from a quarter to a semester plan. The major tasks, the semester schedule, and the recommended grading system are all outlined. A section on kindergarten provides material on proposed curriculum and support materials, the suggested weekly block of…

  15. Ten Commandments of System Conversions.

    ERIC Educational Resources Information Center

    Chabotar, Kent John

    1998-01-01

    Administrators at Bowdoin College (Maine) have translated lessons learned from the process of administrative software conversion into ten commandments for other small colleges undertaking such changes. Three approaches to management information systems are outlined, with advantages and limitations highlighted, as well as the ten recommendations,…

  16. Spin conversion on the nanoscale

    NASA Astrophysics Data System (ADS)

    Otani, Yoshichika; Shiraishi, Masashi; Oiwa, Akira; Saitoh, Eiji; Murakami, Shuichi

    2017-09-01

    Spins can act as mediators to interconvert electricity, light, sound, vibration and heat. Here, we give an overview of the recent advances in different sub-disciplines of spintronics that can be associated with the developing field of spin conversion, and discuss future prospects.

  17. INDOOR EMISSIONS FROM CONVERSION VARNISHES

    EPA Science Inventory

    Conversion varnishes are two-component, acid-catalyzed varnishes that are commonly used to finish cabinets. They are valued for their water- and stain-resistance, as well as their appearance. They have been found, however, to contribute to indoor emissions of organic compounds. F...

  18. Turbulence and energy conversion research

    SciTech Connect

    Hutchinson, R.A.

    1985-07-01

    This report examines the role of fluid mechanics research (particularly turbulence research) in improving energy conversion systems. In this report two of the listed application areas are selected as examples: fluidization and cavitation. Research needs in general, and research possibilities for ECUT in particular, are examined.

  19. Conversations to Transform Geometry Class

    ERIC Educational Resources Information Center

    Szydlik, Jennifer Earles; Parrott, Amy; Belnap, Jason Knight

    2016-01-01

    Classroom culture is negotiated and established through both conversations and practices. Traditionally, teachers and researchers have focused primarily on the individual and social construction of mathematical content--that is, students' conceptual understanding and procedural skills--through mathematical actions and practices. This article…

  20. Direct digital conversion detector technology

    NASA Astrophysics Data System (ADS)

    Mandl, William J.; Fedors, Richard

    1995-06-01

    Future imaging sensors for the aerospace and commercial video markets will depend on low cost, high speed analog-to-digital (A/D) conversion to efficiently process optical detector signals. Current A/D methods place a heavy burden on system resources, increase noise, and limit the throughput. This paper describes a unique method for incorporating A/D conversion right on the focal plane array. This concept is based on Sigma-Delta sampling, and makes optimum use of the active detector real estate. Combined with modern digital signal processors, such devices will significantly increase data rates off the focal plane. Early conversion to digital format will also decrease the signal susceptibility to noise, lowering the communications bit error rate. Computer modeling of this concept is described, along with results from several simulation runs. A potential application for direct digital conversion is also reviewed. Future uses for this technology could range from scientific instruments to remote sensors, telecommunications gear, medical diagnostic tools, and consumer products.

  1. Taking the Grading Conversation Public

    ERIC Educational Resources Information Center

    Reeves, Douglas B.

    2011-01-01

    To manage effective grading reform, education leaders must engage teachers, parents, communities, and policymakers in a rational discussion about grading. Doug Reeves suggests that leaders start the conversation with a discussion of the principles on which all stakeholders can agree; make clear what will not change under the new grading policy; be…

  2. A Conversation with Edwin Shneidman

    ERIC Educational Resources Information Center

    Pestian, John

    2010-01-01

    This article is a transcript of a conversation that took place with Edwin Shneidman, PhD, on August 19, 2008. Recent advances in machine learning, particularly neurocognitive computing, have provided a fresh approach to the idea of using computers to analyze the language of the suicidal person. Here this notion and many others are discussed.

  3. A conversation with Edwin Shneidman.

    PubMed

    Pestian, John

    2010-10-01

    This article is a transcript of a conversation that took place with Edwin Shneidman, PhD, on August 19, 2008. Recent advances in machine learning, particularly neurocognitive computing, have provided a fresh approach to the idea of using computers to analyze the language of the suicidal person. Here this notion and many others are discussed.

  4. Ocean thermal energy conversion (OTEC)

    SciTech Connect

    Lockerby, R.W.

    1981-01-01

    Ocean thermal energy conversion (OTEC) is reviewed briefly. The two types of OTEC system (open and closed) are described and limitations are pointed out. A bibliography of 148 references on OTEC is given for the time period 1975 to 1980. Entries are arranged alphabetically according to the author's name. (MJJ)

  5. Ocean Thermal Energy Conversion (OTEC)

    NASA Technical Reports Server (NTRS)

    Lavi, A.

    1977-01-01

    Energy Research and Development Administration research progress in Ocean Thermal Energy Conversion (OTEC) is outlined. The development program is being focused on cost effective heat exchangers; ammonia is generally used as the heat exchange fluid. Projected costs for energy production by OTEC vary between $1000 to $1700 per kW.

  6. INDOOR EMISSIONS FROM CONVERSION VARNISHES

    EPA Science Inventory

    Conversion varnishes are two-component, acid-catalyzed varnishes that are commonly used to finish cabinets. They are valued for their water- and stain-resistance, as well as their appearance. They have been found, however, to contribute to indoor emissions of organic compounds. F...

  7. Pronominal Chains in English Conversation.

    ERIC Educational Resources Information Center

    Thavenius, Cecilia

    A study of the functions and structure of referential third- person pronominal chains in spontaneous English conversation as compared to those in written English is discussed. The study found the frequencies of these pronouns and of their chains to be generally much higher in the spoken corpus than in the written corpus. In the spoken corpus,…

  8. Batteries: Beyond intercalation and conversion

    NASA Astrophysics Data System (ADS)

    Grimaud, Alexis

    2017-01-01

    Conventional positive electrode materials for lithium-ion batteries, such as intercalation and conversion compounds, feature a host structure to reversibly insert and conduct lithium ions. Now, electrochemically activated transition metal oxide-lithium fluoride composite materials are shown to be a promising class of positive electrodes.

  9. Photovoltaic conversion of laser energy

    NASA Technical Reports Server (NTRS)

    Stirn, R. J.

    1976-01-01

    The Schottky barrier photovoltaic converter is suggested as an alternative to the p/n junction photovoltaic devices for the conversion of laser energy to electrical energy. The structure, current, output, and voltage output of the Schottky device are summarized. The more advanced concepts of the multilayer Schottky barrier cell and the AMOS solar cell are briefly considered.

  10. A Conversation with Edwin Shneidman

    ERIC Educational Resources Information Center

    Pestian, John

    2010-01-01

    This article is a transcript of a conversation that took place with Edwin Shneidman, PhD, on August 19, 2008. Recent advances in machine learning, particularly neurocognitive computing, have provided a fresh approach to the idea of using computers to analyze the language of the suicidal person. Here this notion and many others are discussed.

  11. Hybrid nanorod-polymer solar cells.

    PubMed

    Huynh, Wendy U; Dittmer, Janke J; Alivisatos, A Paul

    2002-03-29

    We demonstrate that semiconductor nanorods can be used to fabricate readily processed and efficient hybrid solar cells together with polymers. By controlling nanorod length, we can change the distance on which electrons are transported directly through the thin film device. Tuning the band gap by altering the nanorod radius enabled us to optimize the overlap between the absorption spectrum of the cell and the solar emission spectrum. A photovoltaic device consisting of 7-nanometer by 60-nanometer CdSe nanorods and the conjugated polymer poly-3(hexylthiophene) was assembled from solution with an external quantum efficiency of over 54% and a monochromatic power conversion efficiency of 6.9% under 0.1 milliwatt per square centimeter illumination at 515 nanometers. Under Air Mass (A.M.) 1.5 Global solar conditions, we obtained a power conversion efficiency of 1.7%.

  12. Hybrid Photovoltaic-Thermal Collectors: A Review

    NASA Astrophysics Data System (ADS)

    Ramos, Figueiredo; Cardoso, António; Alcaso, Adérito

    Solar energy can be converted directly into electric and thermal energy through photovoltaic cells and thermal collectors, respectively. However this conversion, in particular the photovoltaic, has a reduced efficiency. A solution proposed to increase this efficiency is with the hybrid solar structure, which consists in the junction of the photovoltaic panel and the thermal collector in a single module. The interest on these solar systems led the International Energy Agency to create a "Task" on this subject. This paper presents a review of the research in this area, presenting the definitions of the related collectors and results of their characteristics, as well as some ideas for future studies.

  13. Conversion of Biomass Syngas to DME Using a Microchannel Reactor

    SciTech Connect

    Hu, Jianli; Wang, Yong; Cao, Chunshe; Elliott, Douglas C.; Stevens, Don J.; White, James F.

    2005-03-01

    The capability of a microchannel reactor for direct synthesis of dimethylether (DME) from biomass syngas was explored. The reactor was operated in conjunction with a hybrid catalyst system consisting of methanol synthesis and dehydration catalysts, and the influence of reaction parameters on syngas conversion was investigated. The activities of different dehydration catalysts were compared under DME synthesis conditions. Reaction temperature and pressure exhibited similar positive effects on DME formation. A catalytic stability test of the hybrid catalyst system was performed for 880 hours, during which CO conversion only decreased from 88% to 81%. In the microchannel reactor, the catalyst deactivation rate appeared to be much slower than in a tubular fixed-bed reactor tested for comparison. Test results also indicated that the dehydration reaction rate and the water depletion rate via a water-gas-shift reaction should be compatible in order to achieve high selectivity to DME. Using the microchannel reactor, it was possible to achieve a space time yield almost three times higher than commercially demonstrated performance results. A side-by-side comparison indicated that the heat removal capability of the microchannel reactor was at least six times greater than that of a commercial slurry reactor under similar reaction conditions.

  14. Self-consistent conversion of a viscous fluid to particles

    NASA Astrophysics Data System (ADS)

    Molnar, Denes; Wolff, Zack

    2017-02-01

    Comparison of hydrodynamic and "hybrid" hydrodynamics+transport calculations with heavy-ion data inevitably requires the conversion of the fluid to particles. For dissipative fluids the conversion is ambiguous without additional theory input complementing hydrodynamics. We obtain self-consistent shear viscous phase-space corrections from linearized Boltzmann transport theory for a gas of hadrons. These corrections depend on the particle species, and incorporating them in Cooper-Frye freeze-out affects identified particle observables. For example, with additive quark model cross sections, proton elliptic flow is larger than pion elliptic flow at moderately high pT in Au+Au collisions at the BNL Relativistic Heavy Ion Collider. This is in contrast to Cooper-Frye freeze-out with the commonly used "democratic Grad" ansatz that assumes no species dependence. Various analytic and numerical results are also presented for massless and massive two-component mixtures to better elucidate how species dependence arises. For convenient inclusion in pure hydrodynamic and hybrid calculations, Appendix G contains self-consistent viscous corrections for each species both in tabulated and parametrized form.

  15. Conceptual design and system analysis study for a hybrid solar photovoltaic/solar thermal electric power system. Volume 3: Appendices

    NASA Astrophysics Data System (ADS)

    1981-07-01

    Hybrid photovoltaic/solar thermal electric conversion systems were analyzed. Several types of hybrid systems, photovoltaic only systems, and solar thermal electric systems in terms of performance and cost were compared. The computer code used in the analyses and background information on heat engines, thermal efficiencies of photovoltaic thermal collectors, and optical considerations for central receiver plants is also described.

  16. An Automated Approach to Examining Conversational Dynamics between People with Dementia and Their Carers

    PubMed Central

    Atay, Christina; Conway, Erin R.; Angus, Daniel; Wiles, Janet; Baker, Rosemary; Chenery, Helen J.

    2015-01-01

    The progressive neuropathology involved in dementia frequently causes a gradual decline in communication skills. Communication partners who are unaware of the specific communication problems faced by people with dementia (PWD) can inadvertently challenge their conversation partner, leading to distress and a reduced flow of information between speakers. Previous research has produced an extensive literature base recommending strategies to facilitate conversational engagement in dementia. However, empirical evidence for the beneficial effects of these strategies on conversational dynamics is sparse. This study uses a time-efficient computational discourse analysis tool called Discursis to examine the link between specific communication behaviours and content-based conversational engagement in 20 conversations between PWD living in residential aged-care facilities and care staff members. Conversations analysed here were baseline conversations recorded before staff members underwent communication training. Care staff members spontaneously exhibited a wide range of facilitative and non-facilitative communication behaviours, which were coded for analysis of conversation dynamics within these baseline conversations. A hybrid approach combining manual coding and automated Discursis metric analysis provides two sets of novel insights. Firstly, this study revealed nine communication behaviours that, if used by the care staff member in a given turn, significantly increased the appearance of subsequent content-based engagement in the conversation by PWD. Secondly, the current findings reveal alignment between human- and computer-generated labelling of communication behaviour for 8 out of the total 22 behaviours under investigation. The approach demonstrated in this study provides an empirical procedure for the detailed evaluation of content-based conversational engagement associated with specific communication behaviours. PMID:26658135

  17. Solution-Processed Two-Dimensional Metal Dichalcogenide-Based Nanomaterials for Energy Storage and Conversion.

    PubMed

    Cao, Xiehong; Tan, Chaoliang; Zhang, Xiao; Zhao, Wei; Zhang, Hua

    2016-08-01

    The development of renewable energy storage and conversion devices is one of the most promising ways to address the current energy crisis, along with the global environmental concern. The exploration of suitable active materials is the key factor for the construction of highly efficient, highly stable, low-cost and environmentally friendly energy storage and conversion devices. The ability to prepare two-dimensional (2D) metal dichalcogenide (MDC) nanosheets and their functional composites in high yield and large scale via various solution-based methods in recent years has inspired great research interests in their utilization for renewable energy storage and conversion applications. Here, we will summarize the recent advances of solution-processed 2D MDCs and their hybrid nanomaterials for energy storage and conversion applications, including rechargeable batteries, supercapacitors, electrocatalytic hydrogen generation and solar cells. Moreover, based on the current progress, we will also give some personal insights on the existing challenges and future research directions in this promising field.

  18. The New Information Hybrid.

    ERIC Educational Resources Information Center

    Levitan, Karen B.

    1981-01-01

    Discusses the creation and existence of "hybrid" organizations, i.e., nonprofit companies sponsored by the government to provide extensive research and development services. Possibilities for hybrids are brought about by government intervention in the information marketplace to produce social benefits. (SW)

  19. Epigenetic Changes in Hybrids.

    PubMed

    Greaves, Ian K; Gonzalez-Bayon, Rebeca; Wang, Li; Zhu, Anyu; Liu, Pei-Chuan; Groszmann, Michael; Peacock, W James; Dennis, Elizabeth S

    2015-08-01

    Genome-wide approaches to the study of hybrid vigor have identified epigenetic changes in the hybrid nucleus in Arabidopsis (Arabidopsis thaliana), maize (Zea mays), and rice (Oryza sativa). DNA methylation associated with 24-nucleotide small interfering RNAs exhibits transallelic effects in hybrids of Arabidopsis and other species. Some of the transmethylation changes are inherited and some affect gene expression. Hybrids have larger leaves than those of the parents and have increases in cell size and number. The increased leaf size results in a greater photosynthetic capacity, which may support the increased vegetative and reproductive yields of the F1 hybrids. Genes and metabolic pathways that have altered expression relative to the parents include loci involved in responses to hormones and to biotic and abiotic stress. Whereas epigenetically induced changes in gene expression may contribute to hybrid vigor, the link between the transcriptional changes and the hybrid phenotype is not confirmed. Recurrent selection of high yielding F1 lines from the F2/F3 of a number of crops has fixed heterosis yields in pure breeding lines. These hybrid-like lines may have valuable applications in crop systems. © 2015 American Society of Plant Biologists. All Rights Reserved.

  20. Exceeding the solar cell Shockley-Queisser limit via thermal up-conversion of low-energy photons

    NASA Astrophysics Data System (ADS)

    Boriskina, Svetlana V.; Chen, Gang

    2014-03-01

    Maximum efficiency of ideal single-junction photovoltaic (PV) cells is limited to 33% (for 1 sun illumination) by intrinsic losses such as band edge thermalization, radiative recombination, and inability to absorb below-bandgap photons. This intrinsic thermodynamic limit, named after Shockley and Queisser (S-Q), can be exceeded by utilizing low-energy photons either via their electronic up-conversion or via the thermophotovoltaic (TPV) conversion process. However, electronic up-conversion systems have extremely low efficiencies, and practical temperature considerations limit the operation of TPV converters to the narrow-gap PV cells. Here we develop a conceptual design of a hybrid TPV platform, which exploits thermal up-conversion of low-energy photons and is compatible with conventional silicon PV cells by using spectral and directional selectivity of the up-converter. The hybrid platform offers sunlight-to-electricity conversion efficiency exceeding that imposed by the S-Q limit on the corresponding PV cells across a broad range of bandgap energies, under low optical concentration (1-300 suns), operating temperatures in the range 900-1700 K, and in simple flat panel designs. We demonstrate maximum conversion efficiency of 73% under illumination by non-concentrated sunlight. A detailed analysis of non-ideal hybrid platforms that allows for up to 15% of absorption/re-emission losses yields limiting efficiency value of 45% for Si PV cells.

  1. Hybrid rocket performance

    NASA Technical Reports Server (NTRS)

    Frederick, Robert A., Jr.

    1992-01-01

    A hybrid rocket is a system consisting of a solid fuel grain and a gaseous or liquid oxidizer. Figure 1 shows three popular hybrid propulsion cycles that are under current consideration. NASA MSFC has teamed with industry to test two hybrid propulsion systems that will allow scaling to motors of potential interest for Titan and Atlas systems, as well as encompassing the range of interest for SEI lunar ascent stages and National Launch System Cargo Transfer Vehicle (NLS CTV) and NLS deorbit systems. Hybrid systems also offer advantages as moderate-cost, environmentally acceptable propulsion system. The objective of this work was to recommend a performance prediction methodology for hybrid rocket motors. The scope included completion of: a literature review, a general methodology, and a simplified performance model.

  2. Hybrid propulsion technology program

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Technology was identified which will enable application of hybrid propulsion to manned and unmanned space launch vehicles. Two design concepts are proposed. The first is a hybrid propulsion system using the classical method of regression (classical hybrid) resulting from the flow of oxidizer across a fuel grain surface. The second system uses a self-sustaining gas generator (gas generator hybrid) to produce a fuel rich exhaust that was mixed with oxidizer in a separate combustor. Both systems offer cost and reliability improvement over the existing solid rocket booster and proposed liquid boosters. The designs were evaluated using life cycle cost and reliability. The program consisted of: (1) identification and evaluation of candidate oxidizers and fuels; (2) preliminary evaluation of booster design concepts; (3) preparation of a detailed point design including life cycle costs and reliability analyses; (4) identification of those hybrid specific technologies needing improvement; and (5) preperation of a technology acquisition plan and large scale demonstration plan.

  3. Hybrid baryons in QCD

    SciTech Connect

    Dudek, Jozef J.; Edwards, Robert G.

    2012-03-21

    In this study, we present the first comprehensive study of hybrid baryons using lattice QCD methods. Using a large basis of composite QCD interpolating fields we extract an extensive spectrum of baryon states and isolate those of hybrid character using their relatively large overlap onto operators which sample gluonic excitations. We consider the spectrum of Nucleon and Delta states at several quark masses finding a set of positive parity hybrid baryons with quantum numbers $N_{1/2^+},\\,N_{1/2^+},\\,N_{3/2^+},\\, N_{3/2^+},\\,N_{5/2^+},\\,$ and $\\Delta_{1/2^+},\\, \\Delta_{3/2^+}$ at an energy scale above the first band of `conventional' excited positive parity baryons. This pattern of states is compatible with a color octet gluonic excitation having $J^{P}=1^{+}$ as previously reported in the hybrid meson sector and with a comparable energy scale for the excitation, suggesting a common bound-state construction for hybrid mesons and baryons.

  4. The hybrid BCI.

    PubMed

    Pfurtscheller, Gert; Allison, Brendan Z; Brunner, Clemens; Bauernfeind, Gunther; Solis-Escalante, Teodoro; Scherer, Reinhold; Zander, Thorsten O; Mueller-Putz, Gernot; Neuper, Christa; Birbaumer, Niels

    2010-01-01

    Nowadays, everybody knows what a hybrid car is. A hybrid car normally has two engines to enhance energy efficiency and reduce CO2 output. Similarly, a hybrid brain-computer interface (BCI) is composed of two BCIs, or at least one BCI and another system. A hybrid BCI, like any BCI, must fulfill the following four criteria: (i) the device must rely on signals recorded directly from the brain; (ii) there must be at least one recordable brain signal that the user can intentionally modulate to effect goal-directed behaviour; (iii) real time processing; and (iv) the user must obtain feedback. This paper introduces hybrid BCIs that have already been published or are in development. We also introduce concepts for future work. We describe BCIs that classify two EEG patterns: one is the event-related (de)synchronisation (ERD, ERS) of sensorimotor rhythms, and the other is the steady-state visual evoked potential (SSVEP). Hybrid BCIs can either process their inputs simultaneously, or operate two systems sequentially, where the first system can act as a "brain switch". For example, we describe a hybrid BCI that simultaneously combines ERD and SSVEP BCIs. We also describe a sequential hybrid BCI, in which subjects could use a brain switch to control an SSVEP-based hand orthosis. Subjects who used this hybrid BCI exhibited about half the false positives encountered while using the SSVEP BCI alone. A brain switch can also rely on hemodynamic changes measured through near-infrared spectroscopy (NIRS). Hybrid BCIs can also use one brain signal and a different type of input. This additional input can be an electrophysiological signal such as the heart rate, or a signal from an external device such as an eye tracking system.

  5. Progress in understanding conversion disorder

    PubMed Central

    Allin, Matthew; Streeruwitz, Anna; Curtis, Vivienne

    2005-01-01

    Conversion disorder has a history that may reach back into antiquity, and it continues to present a clinical challenge to both psychiatrists and neurologists. This article reviews the current state of knowledge surrounding the prevalence, etiology, and neurobiology of conversion disorder. There have been improvements in the accuracy of diagnosis that are possibly related to improved technologies such as neuroimaging. Once the diagnosis is made, it is important to develop a therapeutic alliance between the patient and the medical team, and where comorbid psychiatric diagnoses have been made, these need to be adequately treated. While there have been no formal trials of medication or psychoanalytic treatments in this disorder, case reports suggest that a combination of antidepressants, psychotherapy, and a multidisciplinary approach to rehabilitation may be beneficial. PMID:18568070

  6. Complexity matching in dyadic conversation.

    PubMed

    Abney, Drew H; Paxton, Alexandra; Dale, Rick; Kello, Christopher T

    2014-12-01

    Recent studies of dyadic interaction have examined phenomena of synchronization, entrainment, alignment, and convergence. All these forms of behavioral matching have been hypothesized to play a supportive role in establishing coordination and common ground between interlocutors. In the present study, evidence is found for a new kind of coordination termed complexity matching. Temporal dynamics in conversational speech signals were analyzed through time series of acoustic onset events. Timing in periods of acoustic energy was found to exhibit behavioral matching that reflects complementary timing in turn-taking. In addition, acoustic onset times were found to exhibit power law clustering across a range of timescales, and these power law functions were found to exhibit complexity matching that is distinct from behavioral matching. Complexity matching is discussed in terms of interactive alignment and other theoretical principles that lead to new hypotheses about information exchange in dyadic conversation and interaction in general.

  7. Coal conversion products Industrial applications

    NASA Technical Reports Server (NTRS)

    Warren, D.; Dunkin, J.

    1980-01-01

    The synfuels economic evaluation model was utilized to analyze cost and product economics of the TVA coal conversion facilities. It is concluded that; (1) moderate yearly future escalations ( 6%) in current natural gas prices will result in medium-Btu gas becoming competitive with natural gas at the plant boundary; (2) utilizing DRI price projections, the alternate synfuel products, except for electricity, will be competitive with their counterparts; (3) central site fuel cell generation of electricity, utilizing MBG, is economically less attractive than the other synthetic fuels, given projected price rises in electricity produced by other means; and (4) because of estimated northern Alabama synfuels market demands, existing conventional fuels, infrastructure and industrial synfuels retrofit problems, a diversity of transportable synfuels products should be produced by the conversion facility.

  8. Conversation, speech acts, and memory.

    PubMed

    Holtgraves, Thomas

    2008-03-01

    Speakers frequently have specific intentions that they want others to recognize (Grice, 1957). These specific intentions can be viewed as speech acts (Searle, 1969), and I argue that they play a role in long-term memory for conversation utterances. Five experiments were conducted to examine this idea. Participants in all experiments read scenarios ending with either a target utterance that performed a specific speech act (brag, beg, etc.) or a carefully matched control. Participants were more likely to falsely recall and recognize speech act verbs after having read the speech act version than after having read the control version, and the speech act verbs served as better recall cues for the speech act utterances than for the controls. Experiment 5 documented individual differences in the encoding of speech act verbs. The results suggest that people recognize and retain the actions that people perform with their utterances and that this is one of the organizing principles of conversation memory.

  9. Ratios of internal conversion coefficients

    SciTech Connect

    Raman, S.; Ertugrul, M.; Nestor, C.W. . E-mail: CNestorjr@aol.com; Trzhaskovskaya, M.B.

    2006-03-15

    We present here a database of available experimental ratios of internal conversion coefficients for different atomic subshells measured with an accuracy of 10% or better for a number of elements in the range 26 {<=} Z {<=} 100. The experimental set involves 414 ratios for pure and 1096 ratios for mixed-multipolarity nuclear transitions in the transition energy range from 2 to 2300 keV. We give relevant theoretical ratios calculated in the framework of the Dirac-Fock method with and without regard for the hole in the atomic subshell after conversion. For comparison, the ratios obtained within the relativistic Hartree-Fock-Slater approximation are also presented. In cases where several ratios were measured for the same transition in a given isotope in which two multipolarities were involved, we present the mixing ratio {delta} {sup 2} obtained by a least squares fit.

  10. Electrocatalysts for carbon dioxide conversion

    DOEpatents

    Masel, Richard I; Salehi-Khojin, Amin

    2015-04-21

    Electrocatalysts for carbon dioxide conversion include at least one catalytically active element with a particle size above 0.6 nm. The electrocatalysts can also include a Helper Catalyst. The catalysts can be used to increase the rate, modify the selectivity or lower the overpotential of electrochemical conversion of CO.sub.2. Chemical processes and devices using the catalysts also include processes to produce CO, HCO.sup.-, H.sub.2CO, (HCO.sub.2).sup.-, H.sub.2CO.sub.2, CH.sub.3OH, CH.sub.4, C.sub.2H.sub.4, CH.sub.3CH.sub.2OH, CH.sub.3COO.sup.-, CH.sub.3COOH, C.sub.2H.sub.6, (COOH).sub.2, or (COO.sup.-).sub.2, and a specific device, namely, a CO.sub.2 sensor.

  11. Photonic applications based on biological/inorganic nano hybrids

    NASA Astrophysics Data System (ADS)

    Zhang, Xin; Wu, Pengfei; Yelleswarapu, Chandra

    2016-02-01

    Biological Retinal is an effective and efficient photochromic compounds and one of the best candidates for photon conversion, transmission and storage, from the view of bionics and natural selection. We observed large optical nonlinearity by using new fabricated films of photoactive Retinol hybrid materials. Based on reversible photoinduced anisotropy and transient optical characteristics, the Retinol hybrids can be used to design novel photonic devices, such as holographic elements, all-optical switch and spatial light modulator. Also, the study is important for further understanding the photochemical mechanism of vision process.

  12. Conversion of heavy petroleum oils

    SciTech Connect

    Farcasiu, M.

    1982-03-02

    Heavy petroleum oils, such as vacuum resids, and heavy fractions of tar sands and shale oil, are partially converted to more volatile hydrocarbons by mixing with light aromatic hydrocarbons and treatment of the mixture with a friedel-crafts catalyst such as aluminum chloride. It is believed that the conversion found is essentially a transalkylation, I.E. The resid undergoes dealkylation with concurrent alkylation of the light aromatic hydrocarbon.

  13. Observation of Thermoacoustic Energy Conversion

    NASA Astrophysics Data System (ADS)

    Tashiro, Yusuke; Biwa, Tetsushi; Yazaki, Taichi

    In order to understand thermoacoustic phenomena from a point of view of thermodynamics, oscillating pressure, velocity and temperature were measured in the tube having a temperature gradient. By converting the measured Eulerian quantities to the Lagrangian quantities associated with a given gas parcel, we determined the local energy conversion rate per unit volume and time. The obtained data demonstrate the validity of the thermodynamic approach to thermoacoustic phenomena.

  14. Materials for thermoelectric energy conversion

    NASA Technical Reports Server (NTRS)

    Wood, C.

    1988-01-01

    The field of thermoelectric energy conversion is reviewed from both a theoretical and an experimental standpoint. The basic theory is introduced and the thermodynamic and solid state views are compared. An overview of the development of thermoelectric materials is presented with particular emphasis being placed on the most recent developments in high-temperature semiconductors. A number of possible device applications are discussed and the successful use and suitability of these devices for space power is manifest.

  15. Explicit Polymorphism and CPS Conversion,

    DTIC Science & Technology

    1992-10-01

    programming language design , the concepts of polymorphism [14, 28, 39] and continuation-passing [38, 41, 43] are of particular interest. The use of...Principles of Programming Languages, January 1991. [9] Matthias Felleisen . The Calculi of X.-CS Conversion: A Syntactic Theory of Control and State in...Imperative Higher-Order Programming Languages. PhD thesis, Indiana University, Bloomington, IN, 1987. 18 [10] Matthias Felleisen and Daniel Friedman

  16. Allocation of speech in conversation.

    PubMed

    Simon, Carsta; Baum, William M

    2017-03-01

    In a replication and extension of Conger and Killeen's (1974) widely cited demonstration of matching in conversations, we evaluated nine participants' allocation of speech and gaze to two conversational partners. German speakers participated in two 90-min sessions in which confederates uttered approval on independent variable-interval schedules. In one of the sessions, confederates uttered approval contingent upon and contiguous with eye contact whereas in the other session approval was uttered independent of the participant's gaze. Several measures of participants' verbal behavior were taken, including relative duration and rate of speech and gaze. These were compared to confederates' relative rate of approval and relative duration and rate of talk. The generalized matching equation was fitted to the various relations between participants' behavior and confederates' behavior. Conger and Killeen's results were not replicated; participants' response allocation did not show a systematic relation to the confederates' relative rate of approval. The strongest relations were to overall talk, rather than approval. In both conditions, the participant talked more to the confederate who talked less-inverse or antimatching. Participants' gaze showed the same inverse relation to the confederates' talk. Requiring gaze to be directed toward a confederate for delivery of approval made no difference in the results. The absence of a difference combined with prior research suggests that matching or antimatching in conversations is more likely due to induction than to reinforcement.

  17. Hemicellulose conversion by anaerobic digestion

    SciTech Connect

    Ghosh, S.; Henry, M.P.; Christopher, R.W.

    1982-01-01

    The digestibility of an aquatic biomass (water hyacinth), a land-based biomass (Coastal Bermuda grass), and a biomass-waste blend (a mixture of hyacinth, grass, MSW, and sludge) under various digestion conditions was studied. Anaerobic digestion of hemicellulose consists of the steps of enzymatic hydrolysis of hemicellulose to glucans, mannans, galactans, xylans, and arabans, and then to simple hexose and pentose sugars; production of C/sub 2/ and higher fatty acids from the simple sugars; conversion of higher fatty acids to acetate; and finally, production of methane and CO/sub 2/ from acetate, and CO/sub 2/ and hydrogen. The conversion of hemicellulose was higher under mesophilic conditions than those of cellulose or protein for all biomass test feeds, probably because the hemicellulose structure was more vulnerable to enzymatic attack than that of the lignocellulosic component. Cellulose conversion efficiencies at the mesophilic and thermophilic temperatures were about the same. However, hemicellulose was converted at a much lower efficiency than cellulose during thermophilic digestion - a situation that was the reverse of that observed at the mesophilic temperature. Cellulose was utilized in preference to hemicellulose during mesophilic digestion of nitrogen-supplemented Bermuda grass. It was speculated that Bermuda grass cellulose was converted at a higher efficiency than hemicellulose in the presence of external nitrogen because the metabolism of the breakdown product (glucose) of cellulose requires the least investment of enzymes and energy.

  18. Irradiation enhancement of biomass conversion

    NASA Astrophysics Data System (ADS)

    Smith, G. S.; Kiesling, H. E.; Galyean, M. L.; Bader, J. R.

    The vast supply of cellulosic agricultural residues and industrial by-products that is produced each year is a prospective resource of biomass suitable for conversion to useful products such as feedstock for the chemicals industry and feedstuffs for the livestock industry. Conversions of such biomass is poor at present, and utilization is inefficient, because of physio-chemical barriers to biological degradation and (or) anti-quality components such as toxicants that restrict biological usages. Improvements in biodegradability of ligno-cellulosic materials have been accomplished by gamma-ray and electron-beam irradiation at intermediate dosage (˜ 50 Mrad; .5 MGy); but applications of the technology have been hampered by questionable interpretations of results. Recent research with organic wastes such as sewage sludge and straw suggests opportunity for important applications of irradiation technology in enhancement of biomass conversion. Data from experiments using irradiated straw as feed for ruminants are presented and discussed in relation to research on prospective usage of sewage products as feed for ruminants. Findings are discussed in regard to prospective applications in industrial fermentation processes. Possible usage of irradiation technology for destruction of toxicants in exotic plants is considered in regard to prospective new feedstuffs.

  19. Methanol conversion to higher hydrocarbons

    SciTech Connect

    Tabak, S.A.

    1994-12-31

    Several indirect options exist for producing chemicals and transportation fuels from coal, natural gas, or biomass. All involve an initial conversion step to synthesis gas (CO and H{sub 2}). Presently, there are two commercial technologies for converting syngas to liquids: Fischer-Tropsch, which yields a range of aliphatic hydrocarbons with molecular weights determined by Schulz-Flory kinetics, and methanol synthesis. Mobil`s diversity of technology for methanol conversion gives the methanol synthesis route flexibility for production of either gasoline, distillate or chemicals. Mobil`s ZSM-5 catalyst is the key in several processes for producing chemicals and transportation fuels from methanol: MTO for light olefins, MTG for gasoline, MOGD for distillates. The MTG process has been commercialized in New Zealand since 1985, producing one-third of the country`s gasoline supply, while MTO and MOGD have been developed and demonstrated at greater than 100 BPD scale. This paper will discuss recent work in understanding methanol conversion chemistry and the various options for its use.

  20. Fitness of hybrids between rapeseed (Brassica napus) and wild Brassica rapa in natural habitats.

    PubMed

    Allainguillaume, J; Alexander, M; Bullock, J M; Saunders, M; Allender, C J; King, G; Ford, C S; Wilkinson, M J

    2006-04-01

    Fitness of hybrids between genetically modified (GM) crops and wild relatives influences the likelihood of ecological harm. We measured fitness components in spontaneous (non-GM) rapeseed x Brassica rapa hybrids in natural populations. The F1 hybrids yielded 46.9% seed output of B. rapa, were 16.9% as effective as males on B. rapa and exhibited increased self-pollination. Assuming 100% GM rapeseed cultivation, we conservatively predict < 7000 second-generation transgenic hybrids annually in the United Kingdom (i.e. approximately 20% of F1 hybrids). Conversely, whilst reduced hybrid fitness improves feasibility of bio-containment, stage projection matrices suggests broad scope for some transgenes to offset this effect by enhancing fitness.

  1. Recent developments of hybrid nanocrystal/polymer bulk heterojunction solar cells.

    PubMed

    Tang, Aiwei; Qu, Shengchun; Teng, Feng; Hou, Yanbing; Wang, Yongsheng; Wang, Zhanguo

    2011-11-01

    Hybrid nanocrystal/polymer bulk heterojunction (BHJ) solar cells consisting of colloidal inorganic semiconductor nanocrystals as electron acceptors and conjugated polymers as electron donors have been extensively investigated in the past few decades, which take advantage of the strongpoints of the inorganic semiconductor nanocrystals and the conjugated polymers. Currently, power conversion efficiency over 3% for the hybrid nanocrystal/polymer BHJ solar cells has been achieved. Although the development of hybrid nanocrystal/polymer BHJ solar cells lacks behind the international level, great progress in this research field has been made in China. In this article, we first review the general fabrication techniques and general working principles of hybrid nanocrystal/polymer BHJ solar cells. Secondly, we highlight the international and national developments of hybrid nanocrystal/polymer BHJ solar cells based on different types of semiconductor nanocrystals and conjugated polymers. Finally, we give a future outlook for the hybrid nanocrystal/polymer BHJ solar cells in the worldwide.

  2. High efficiency inorganic/organic hybrid tandem solar cells.

    PubMed

    Seo, Ji Hoon; Kim, Dong-Ho; Kwon, Se-Hun; Song, Myungkwan; Choi, Min-Seung; Ryu, Seung Yoon; Lee, Hyung Woo; Park, Yun Chang; Kwon, Jung-Dae; Nam, Kee-Seok; Jeong, Yongsoo; Kang, Jae-Wook; Kim, Chang Su

    2012-08-28

    Hybrid tandem solar cells comprising an inorganic bottom cell and an organic top cell have been designed and fabricated. The interlayer combination and thickness matching were optimized in order to increase the overall photovoltaic conversion efficiency. A maximum power conversion efficiency of 5.72% was achieved along with a V(oc) of 1.42 V, reaching as high as 92% of the sum of the subcell V(oc) values. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Hybrid vigour in dogs?

    PubMed

    Nicholas, Frank W; Arnott, Elizabeth R; McGreevy, Paul D

    2016-08-01

    Evidence from other species justifies the hypotheses that useful hybrid vigour occurs in dogs and that it can be exploited for improved health, welfare and fitness for purpose. Unfortunately, most of the relevant published canine studies do not provide estimates of actual hybrid vigour because of inadequate specification of the parentage of mixed-bred dogs. To our knowledge, only three published studies have shed any light on actual hybrid vigour in dogs. There are two reports of actual hybrid vigour between Labrador and Golden retrievers, the first ranging from +2.5% to -6.0% for components of a standardised applied-stimulus behavioural test, and the second being at least +12.4% for chance of graduating as a guide dog. The third study provides a minimum estimate of negative actual hybrid vigour: crossbreds between Labrador retrievers and poodles had a higher prevalence of multifocal retinal dysplasia than the average prevalence in their purebred parent breeds. The lack of estimates of actual hybrid vigour can be overcome by including the exact nature of the cross (e.g. F1, F2 or backcross) and their purebred parental breeds in the specification of mixed-bred dogs. Even if only F1 crossbreds can be categorised, this change would enable researchers to conduct substantial investigations to determine whether hybrid vigour has any utility for dog breeding. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Improved laser-to-proton conversion efficiency in isolated reduced mass targets

    SciTech Connect

    Morace, A.; Bellei, C.; Patel, P. K.; Bartal, T.; Kim, J.; Beg, F. N.; Willingale, L.; Maksimchuk, A.; Krushelnick, K.; Wei, M. S.; Batani, D.; Piovella, N.; Stephens, R. B.

    2013-07-29

    We present experimental results of laser-to-proton conversion efficiency as a function of lateral confinement of the refluxing electrons. Experiments were carried out using the T-Cubed laser at the Center for Ultrafast Optical Science, University of Michigan. We demonstrate that the laser-to-proton conversion efficiency increases by 50% with increased confinement of the target from surroundings with respect to a flat target of the same thickness. Three-dimensional hybrid particle-in-cell simulations using LSP code agree with the experimental data. The adopted target design is suitable for high repetition rate operation as well as for Inertial Confinement Fusion applications.

  5. Improved laser-to-proton conversion efficiency in isolated reduced mass targets

    NASA Astrophysics Data System (ADS)

    Morace, A.; Bellei, C.; Bartal, T.; Willingale, L.; Kim, J.; Maksimchuk, A.; Krushelnick, K.; Wei, M. S.; Patel, P. K.; Batani, D.; Piovella, N.; Stephens, R. B.; Beg, F. N.

    2013-07-01

    We present experimental results of laser-to-proton conversion efficiency as a function of lateral confinement of the refluxing electrons. Experiments were carried out using the T-Cubed laser at the Center for Ultrafast Optical Science, University of Michigan. We demonstrate that the laser-to-proton conversion efficiency increases by 50% with increased confinement of the target from surroundings with respect to a flat target of the same thickness. Three-dimensional hybrid particle-in-cell simulations using LSP code agree with the experimental data. The adopted target design is suitable for high repetition rate operation as well as for Inertial Confinement Fusion applications.

  6. Study of a condition for the mode conversion from purely perpendicular electrostatic waves to electromagnetic waves

    NASA Astrophysics Data System (ADS)

    Kalaee, Mohammad Javad; Katoh, Yuto

    2016-07-01

    One of the mechanisms for generating electromagnetic plasma waves (Z-mode and LO-mode) is mode conversion from electrostatic waves into electromagnetic waves in inhomogeneous plasma. Herein, we study a condition required for mode conversion of electrostatic waves propagating purely perpendicular to the ambient magnetic field, by numerically solving the full dispersion relation. An approximate model is derived describing the coupling between electrostatic waves (hot plasma Bernstein mode) and Z-mode waves at the upper hybrid frequency. The model is used to study conditions required for mode conversion from electrostatic waves (electrostatic electron cyclotron harmonic waves, including Bernstein mode) into electromagnetic plasma waves (LO-mode). It is shown that for mode conversion to occur in inhomogeneous plasma, the angle between the boundary surface and the magnetic field vector should be within a specific range. The range of the angle depends on the norm of the k vector of waves at the site of mode conversion in the inhomogeneous region. The present study reveals that inhomogeneity alone is not a sufficient condition for mode conversion from electrostatic waves to electromagnetic plasma waves and that the angle between the magnetic field and the density gradient plays an important role in the conversion process.

  7. Study of a condition for the mode conversion from purely perpendicular electrostatic waves to electromagnetic waves

    SciTech Connect

    Kalaee, Mohammad Javad; Katoh, Yuto

    2016-07-15

    One of the mechanisms for generating electromagnetic plasma waves (Z-mode and LO-mode) is mode conversion from electrostatic waves into electromagnetic waves in inhomogeneous plasma. Herein, we study a condition required for mode conversion of electrostatic waves propagating purely perpendicular to the ambient magnetic field, by numerically solving the full dispersion relation. An approximate model is derived describing the coupling between electrostatic waves (hot plasma Bernstein mode) and Z-mode waves at the upper hybrid frequency. The model is used to study conditions required for mode conversion from electrostatic waves (electrostatic electron cyclotron harmonic waves, including Bernstein mode) into electromagnetic plasma waves (LO-mode). It is shown that for mode conversion to occur in inhomogeneous plasma, the angle between the boundary surface and the magnetic field vector should be within a specific range. The range of the angle depends on the norm of the k vector of waves at the site of mode conversion in the inhomogeneous region. The present study reveals that inhomogeneity alone is not a sufficient condition for mode conversion from electrostatic waves to electromagnetic plasma waves and that the angle between the magnetic field and the density gradient plays an important role in the conversion process.

  8. Optimization of levulinic acid from lignocellulosic biomass using a new hybrid catalyst.

    PubMed

    Ya'aini, Nazlina; Amin, Nor Aishah Saidina; Asmadi, Mohd

    2012-07-01

    Conversion of glucose, empty fruit bunch (efb) and kenaf to levulinic acid over a new hybrid catalyst has been investigated in this study. The characterization and catalytic performance results revealed that the physico-chemical properties of the new hybrid catalyst comprised of chromium chloride and HY zeolite increased the levulinic acid production from glucose compared to the parent catalysts. Optimization of the glucose conversion process using two level full factorial designs (2(3)) with two center points reported 55.2% of levulinic acid yield at 145.2 °C, 146.7 min and 12.0% of reaction temperature, reaction time and catalyst loading, respectively. Subsequently, the potential of efb and kenaf for producing levulinic acid at the optimum conditions was established after 53.2% and 66.1% of efficiencies were reported. The observation suggests that the hybrid catalyst has a potential to be used in biomass conversion to levulinic acid.

  9. Hybrid Bloch brane

    NASA Astrophysics Data System (ADS)

    Bazeia, D.; Lima, Elisama E. M.; Losano, L.

    2017-02-01

    This work reports on models described by two real scalar fields coupled with gravity in the five-dimensional spacetime, with a warped geometry involving one infinite extra dimension. Through a mechanism that smoothly changes a thick brane into a hybrid brane, one investigates the appearance of hybrid branes hosting internal structure, characterized by the splitting on the energy density and the volcano potential, induced by the parameter which controls interactions between the two scalar fields. In particular, we investigate distinct symmetric and asymmetric hybrid brane scenarios.

  10. Hybrid electric vehicles TOPTEC

    SciTech Connect

    1994-06-21

    This one-day TOPTEC session began with an overview of hybrid electric vehicle technology. Updates were given on alternative types of energy storage, APU control for low emissions, simulation programs, and industry and government activities. The keynote speech was about battery technology, a key element to the success of hybrids. The TOPEC concluded with a panel discussion on the mission of hybrid electric vehicles, with a perspective from industry and government experts from United States and Canada on their view of the role of this technology.

  11. Hybrid Vibrio vulnificus

    PubMed Central

    Cohen, Daniel I.; Harding, Rosalind M.; Falush, Daniel; Crook, Derrick W.; Peto, Tim; Maiden, Martin C.

    2005-01-01

    The recent emergence of the human-pathogenic Vibrio vulnificus in Israel was investigated by using multilocus genotype data and modern molecular evolutionary analysis tools. We show that this pathogen is a hybrid organism that evolved by the hybridization of the genomes from 2 distinct and independent populations. These findings provide clear evidence of how hybridization between 2 existing and nonpathogenic forms has apparently led to the emergence of an epidemic infectious disease caused by this pathogenic variant. This novel observation shows yet another way in which epidemic organisms arise. PMID:15705319

  12. Hybrid matrix fiber composites

    DOEpatents

    Deteresa, Steven J.; Lyon, Richard E.; Groves, Scott E.

    2003-07-15

    Hybrid matrix fiber composites having enhanced compressive performance as well as enhanced stiffness, toughness and durability suitable for compression-critical applications. The methods for producing the fiber composites using matrix hybridization. The hybrid matrix fiber composites include two chemically or physically bonded matrix materials, whereas the first matrix materials are used to impregnate multi-filament fibers formed into ribbons and the second matrix material is placed around and between the fiber ribbons that are impregnated with the first matrix material and both matrix materials are cured and solidified.

  13. Artificial mismatch hybridization

    DOEpatents

    Guo, Zhen; Smith, Lloyd M.

    1998-01-01

    An improved nucleic acid hybridization process is provided which employs a modified oligonucleotide and improves the ability to discriminate a control nucleic acid target from a variant nucleic acid target containing a sequence variation. The modified probe contains at least one artificial mismatch relative to the control nucleic acid target in addition to any mismatch(es) arising from the sequence variation. The invention has direct and advantageous application to numerous existing hybridization methods, including, applications that employ, for example, the Polymerase Chain Reaction, allele-specific nucleic acid sequencing methods, and diagnostic hybridization methods.

  14. 5 CFR 317.302 - Conversion procedures.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... requests conversion to career appointment. Failure to respond shall be deemed a declination. (b) Employees... declination. (5) Effective date. A conversion under this section for an employee who elects to join the SES...

  15. 5 CFR 317.302 - Conversion procedures.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... requests conversion to career appointment. Failure to respond shall be deemed a declination. (b) Employees... declination. (5) Effective date. A conversion under this section for an employee who elects to join the SES...

  16. 5 CFR 317.302 - Conversion procedures.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... requests conversion to career appointment. Failure to respond shall be deemed a declination. (b) Employees... declination. (5) Effective date. A conversion under this section for an employee who elects to join the SES...

  17. 5 CFR 317.302 - Conversion procedures.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... requests conversion to career appointment. Failure to respond shall be deemed a declination. (b) Employees... declination. (5) Effective date. A conversion under this section for an employee who elects to join the SES...

  18. 5 CFR 317.302 - Conversion procedures.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... requests conversion to career appointment. Failure to respond shall be deemed a declination. (b) Employees... declination. (5) Effective date. A conversion under this section for an employee who elects to join the SES...

  19. Molten Slag Would Boost Coal Conversion

    NASA Technical Reports Server (NTRS)

    Ferrall, J. F.

    1984-01-01

    Reactor increases residence time of uncovered char. Near-100percent carbon conversion achievable in reactor incorporating moltenslag bath. Slag maintains unconverted carbon impinging on surface at high temperatures for longer period of time, enhancing conversion.

  20. Interrogative suggestibility in patients with conversion disorders.

    PubMed

    Foong, J; Lucas, P A; Ron, M A

    1997-09-01

    We tested the hypothesis that increased interrogative suggestibility may contribute to the shaping and maintaining of conversions symptoms. Interrogative suggestibility was measured in 12 patients with conversion disorder and 10 control patients with confirmed neurological disease matched for age, premorbid intelligence, and as closely as possible in terms of their neurological symptoms to the patients with conversion disorder. Our observations do not support the contention that individual differences in interrogative suggestibility are of importance in the etiology of conversion disorders.

  1. Chaotic mixer improves microarray hybridization.

    PubMed

    McQuain, Mark K; Seale, Kevin; Peek, Joel; Fisher, Timothy S; Levy, Shawn; Stremler, Mark A; Haselton, Frederick R

    2004-02-15

    Hybridization is an important aspect of microarray experimental design which influences array signal levels and the repeatability of data within an array and across different arrays. Current methods typically require 24h and use target inefficiently. In these studies, we compare hybridization signals obtained in conventional static hybridization, which depends on diffusional target delivery, with signals obtained in a dynamic hybridization chamber, which employs a fluid mixer based on chaotic advection theory to deliver targets across a conventional glass slide array. Microarrays were printed with a pattern of 102 identical probe spots containing a 65-mer oligonucleotide capture probe. Hybridization of a 725-bp fluorescently labeled target was used to measure average target hybridization levels, local signal-to-noise ratios, and array hybridization uniformity. Dynamic hybridization for 1h with 1 or 10ng of target DNA increased hybridization signal intensities approximately threefold over a 24-h static hybridization. Similarly, a 10- or 60-min dynamic hybridization of 10ng of target DNA increased hybridization signal intensities fourfold over a 24h static hybridization. In time course studies, static hybridization reached a maximum within 8 to 12h using either 1 or 10ng of target. In time course studies using the dynamic hybridization chamber, hybridization using 1ng of target increased to a maximum at 4h and that using 10ng of target did not vary over the time points tested. In comparison to static hybridization, dynamic hybridization reduced the signal-to-noise ratios threefold and reduced spot-to-spot variation twofold. Therefore, we conclude that dynamic hybridization based on a chaotic mixer design improves both the speed of hybridization and the maximum level of hybridization while increasing signal-to-noise ratios and reducing spot-to-spot variation.

  2. The Teacher and the Conversational Situation

    ERIC Educational Resources Information Center

    Fenn, Peter

    1977-01-01

    Cites a typical classroom "pseudo-conversation," showing how German students of English sound stiff and clumsy when conversing with English-speaking partners. This is blamed partly on the teacher's behavior. The example is then expanded into a "communicative exchange." In teaching conversation, manner is seen as more important…

  3. Adaptive Feedback Improving Learningful Conversations at Workplace

    ERIC Educational Resources Information Center

    Gaeta, Matteo; Mangione, Giuseppina Rita; Miranda, Sergio; Orciuoli, Francesco

    2013-01-01

    This work proposes the definition of an Adaptive Conversation-based Learning System (ACLS) able to foster computer-mediated tutorial dialogues at the workplace in order to increase the probability to generate meaningful learning during conversations. ACLS provides a virtual assistant selecting the best partner to involve in the conversation and…

  4. Alkaline Hydrolysis Conversion of Nitrocellulose Fines

    DTIC Science & Technology

    1997-10-01

    The conversion of 1,125,000 pounds of bone-dry nitrocellulose fines into a liquid fertilizer was documented. Alkaline hydrolysis was the conversion... fertilizer . Fertilizer nutrient value was 1.3% nitrogen (N), 8.0% potassium (K2O) and 0.9% phosphorus (P2O5). Conversion met all applicable federal and state safety and environmental regulations.

  5. Teaching Conversation Using a Television Soap.

    ERIC Educational Resources Information Center

    Grant, Lynn E.

    1996-01-01

    Examines an approach to teaching conversation in New Zealand to adult migrants studying English as a Second Language, using language data from a television soap opera. Compares teacher-made samples of conversation and the scripted conversation of television soaps and points to advantages of using videoed television samples. (15 references)…

  6. 47 CFR 80.761 - Conversion graphs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Conversion graphs. 80.761 Section 80.761... MARITIME SERVICES Standards for Computing Public Coast Station VHF Coverage § 80.761 Conversion graphs. The following graphs must be employed where conversion from one to the other of the indicated types of units...

  7. 47 CFR 80.761 - Conversion graphs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Conversion graphs. 80.761 Section 80.761... MARITIME SERVICES Standards for Computing Public Coast Station VHF Coverage § 80.761 Conversion graphs. The following graphs must be employed where conversion from one to the other of the indicated types of units...

  8. 47 CFR 80.761 - Conversion graphs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Conversion graphs. 80.761 Section 80.761... MARITIME SERVICES Standards for Computing Public Coast Station VHF Coverage § 80.761 Conversion graphs. The following graphs must be employed where conversion from one to the other of the indicated types of units...

  9. 47 CFR 80.761 - Conversion graphs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Conversion graphs. 80.761 Section 80.761... MARITIME SERVICES Standards for Computing Public Coast Station VHF Coverage § 80.761 Conversion graphs. The following graphs must be employed where conversion from one to the other of the indicated types of units...

  10. 47 CFR 80.761 - Conversion graphs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Conversion graphs. 80.761 Section 80.761... MARITIME SERVICES Standards for Computing Public Coast Station VHF Coverage § 80.761 Conversion graphs. The following graphs must be employed where conversion from one to the other of the indicated types of units...

  11. 5 CFR 536.303 - Geographic conversion.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... after geographic conversion is the employee's existing payable rate of basic pay in effect immediately before the action. (b) Geographic conversion when a retained rate employee's official worksite is changed... 5 Administrative Personnel 1 2011-01-01 2011-01-01 false Geographic conversion. 536.303...

  12. 5 CFR 536.303 - Geographic conversion.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... after geographic conversion is the employee's existing payable rate of basic pay in effect immediately before the action. (b) Geographic conversion when a retained rate employee's official worksite is changed... 5 Administrative Personnel 1 2010-01-01 2010-01-01 false Geographic conversion. 536.303...

  13. Retrospective Conversion of Three Library Collections.

    ERIC Educational Resources Information Center

    Johnson, Carolyn A.

    1982-01-01

    Reports on the retrospective conversion via OCLC of cataloging for three library collections at the University of South Carolina--the main, rare book, and historical collections. Backgrounds of the collections, conversion procedures, determinants of conversion rates, and cost factors are discussed. (Author/JL)

  14. 5 CFR 317.301 - Conversion coverage.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... THE SENIOR EXECUTIVE SERVICE Conversion to the Senior Executive Service § 317.301 Conversion coverage... implementation of the Senior Executive Service effective on July 13, 1979, and the initial conversions thereto. (2) The implementation of the Senior Executive Service in an agency following the revocation of that...

  15. Conversational Knowledge Process for Social Technology

    NASA Astrophysics Data System (ADS)

    Nishida, Toyoaki

    The conversational knowledge process is a collective activity for knowledge creation, management, and application where conversational communications are used as a primary means of interaction among participating actors. In this article, I survey a suite of communication tools that augment the conversational knowledge process in order to accelerate social problem solving.

  16. Nonverbal Behavior Generator for Embodied Conversational Agents

    DTIC Science & Technology

    2006-01-01

    position for alternatives or items in a list. Ekman [10] describes eyebrow movements for emotional expressions and conversational signals. Some...2005) 10. Ekman , P.: About brows: emotional and conversational signals. In von Cranach, M., Foppa, K., Lepenies, W., Ploog, D., eds.: Human Ethology...behavior can in turn influence the beliefs, emotions , and behavior of observers. Embodied conversational agents (ECA) with appropriate nonverbal

  17. Teaching Casual Conversation: The Issue of Simplification.

    ERIC Educational Resources Information Center

    Slade, Diana; Gardner, Rod

    This paper focuses on the issue of whether pedagogical mediation will facilitate the acquisition of conversational skills. It argues that it is possible to describe casual conversation, that it has a grammatical structure, and that it is of benefit to English-as-a-Second-Language (ESL) learners for the structure of conversation to be explicitly…

  18. 31 CFR 800.205 - Conversion.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance:Treasury 3 2013-07-01 2013-07-01 false Conversion. 800.205 Section 800.205 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF INVESTMENT... FOREIGN PERSONS Definitions § 800.205 Conversion. The term conversion means the exercise of a right...

  19. 31 CFR 800.205 - Conversion.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 31 Money and Finance:Treasury 3 2011-07-01 2011-07-01 false Conversion. 800.205 Section 800.205 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF INVESTMENT... FOREIGN PERSONS Definitions § 800.205 Conversion. The term conversion means the exercise of a right...

  20. 31 CFR 800.205 - Conversion.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance:Treasury 3 2014-07-01 2014-07-01 false Conversion. 800.205 Section 800.205 Money and Finance: Treasury Regulations Relating to Money and Finance (Continued) OFFICE OF INVESTMENT... FOREIGN PERSONS Definitions § 800.205 Conversion. The term conversion means the exercise of a right...

  1. Hybrid geared traction transmissions

    NASA Technical Reports Server (NTRS)

    Nasvytis, A. L.; White, G.

    1983-01-01

    The basic configuration of geared traction drives, geometric and structural factors to be considered in their construction, and current work on hybrid helicopter transmissions rated at 500 and 3000 hp are discussed.

  2. Hybrid plasmachemical reactor

    SciTech Connect

    Lelevkin, V. M. Smirnova, Yu. G.; Tokarev, A. V.

    2015-04-15

    A hybrid plasmachemical reactor on the basis of a dielectric barrier discharge in a transformer is developed. The characteristics of the reactor as functions of the dielectric barrier discharge parameters are determined.

  3. Hybrid adsorptive membrane reactor

    NASA Technical Reports Server (NTRS)

    Tsotsis, Theodore T. (Inventor); Sahimi, Muhammad (Inventor); Fayyaz-Najafi, Babak (Inventor); Harale, Aadesh (Inventor); Park, Byoung-Gi (Inventor); Liu, Paul K. T. (Inventor)

    2011-01-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  4. Hybrid adsorptive membrane reactor

    DOEpatents

    Tsotsis, Theodore T [Huntington Beach, CA; Sahimi, Muhammad [Altadena, CA; Fayyaz-Najafi, Babak [Richmond, CA; Harale, Aadesh [Los Angeles, CA; Park, Byoung-Gi [Yeosu, KR; Liu, Paul K. T. [Lafayette Hill, PA

    2011-03-01

    A hybrid adsorbent-membrane reactor in which the chemical reaction, membrane separation, and product adsorption are coupled. Also disclosed are a dual-reactor apparatus and a process using the reactor or the apparatus.

  5. Hybrid polymer microspheres

    NASA Technical Reports Server (NTRS)

    Rembaum, A.

    1980-01-01

    Techniques have been successfully tested for bonding polymeric spheres, typically 0.1 micron in diameter, to spheres with diameter up to 100 microns. Hybrids are being developed as improved packing material for ion-exchange columns, filters, and separators.

  6. Plum and plum hybrids.

    USDA-ARS?s Scientific Manuscript database

    Thirteen plum and plum hybrid cultivars are briefly described for the Fruit and Nut Register 46. This register is made to keep the plum industry and researchers up to date on the latest cultivars released....

  7. Plum and plum hybrids.

    USDA-ARS?s Scientific Manuscript database

    Thirty-six plum and plum hybrid cultivars are briefly described for the Fruit and Nut Register 45. This register is made to keep the plum industry and researchers up to date on the latest cultivars released....

  8. Hybrid thermocouple development program

    NASA Technical Reports Server (NTRS)

    Garvey, L. P.; Krebs, T. R.; Lee, E.

    1971-01-01

    The design and development of a hybrid thermocouple, having a segmented SiGe-PbTe n-leg encapsulated within a hollow cylindrical p-SiGe leg, is described. Hybrid couple efficiency is calculated to be 10% to 15% better than that of a all-SiGe couple. A preliminary design of a planar RTG, employing hybrid couples and a water heat pipe radiator, is described as an example of a possible system application. Hybrid couples, fabricated initially, were characterized by higher than predicted resistance and, in some cases, bond separations. Couples made later in the program, using improved fabrication techniques, exhibited normal resistances, both as-fabricated and after 700 hours of testing. Two flat-plate sections of the reference design thermoelectric converter were fabricated and delivered to NASA Lewis for testing and evaluation.

  9. Alpine radar conversion for LAWR

    NASA Astrophysics Data System (ADS)

    Savina, M.; Burlando, P.

    2012-04-01

    The Local Area Weather Radar (LAWR) is a ship-born weather radar system operating in X-band developed by the DHI Group to detect precipitation in urban areas. To date more than thirty units are installed in different settings around the world. A LAWR was also deployed in the Alps, at 3883 m a.s.l. on the Kl. Matterhorn (Valais, Switzerland). This was the highest LAWR of the world and it led to the development of an Alpine LAWR system that, besides featuring important technological improvements needed to withstand the severe Alpine conditions, required the development of a new Alpine Radar COnversion Model (ARCOM), which is the main focus of this contribution. The LAWR system is equipped with the original FURUNO fan-beam slotted antenna and the original logarithmic receiver, which limits the radar observations to the video signal (L) withour providing the reflectivity (Z). The beam is 0.95 deg wide and 20 deg high. It can detect precipitation to a max range of 60 km. In order to account for the limited availability of raw signal and information and the specific mountain set-up, the conversion model had to be developed differently from the state-of-the-art radar conversion technique used for this class of radars. In particular, the ARCOM is based on a model used to simulate a spatial dependent factor, hereafter called ACF, which is in turn function of parameters that take in account climatological conditions, also used in other conversion methods, but additionally accounting for local radar beam features and for orographic forcings such as the effective sampling power (sP), which is modelled by means of antenna pattern, geometric ground clutter and their interaction. The result is a conversion factor formulated to account for a range correction that is based on the increase of the sampling volume, partial beam blocking and local climatological conditions. The importance of the latter in this study is double with respect to the standard conversion technique for this

  10. Serogroup Conversion of Vibrio cholerae in Aquatic Reservoirs

    PubMed Central

    Blokesch, Melanie; Schoolnik, Gary K

    2007-01-01

    The environmental reservoirs for Vibrio cholerae are natural aquatic habitats, where it colonizes the chitinous exoskeletons of copepod molts. Growth of V. cholerae on a chitin surface induces competence for natural transformation, a mechanism for intra-species gene exchange. The antigenically diverse O-serogroup determinants of V. cholerae are encoded by a genetically variable biosynthetic cluster of genes that is flanked on either side by chromosomal regions that are conserved between different serogroups. To determine whether this genomic motif and chitin-induced natural transformation might enable the exchange of serogroup-specific gene clusters between different O serogroups of V. cholerae, a strain of V. cholerae O1 El Tor was co-cultured with a strain of V. cholerae O139 Bengal within a biofilm on the same chitin surface immersed in seawater, and O1-to-O139 transformants were obtained. Serogroup conversion of the O1 recipient by the O139 donor was demonstrated by comparative genomic hybridization, biochemical and serological characterization of the O-antigenic determinant, and resistance of O1-to-O139 transformants to bacteriolysis by a virulent O1-specific phage. Serogroup conversion was shown to have occurred as a single-step exchange of large fragments of DNA. Crossovers were localized to regions of homology common to other V. cholerae serogroups that flank serogroup-specific encoding sequences. This result and the successful serogroup conversion of an O1 strain by O37 genomic DNA indicate that chitin-induced natural transformation might be a common mechanism for serogroup conversion in aquatic habitats and for the emergence of V. cholerae variants that are better adapted for survival in environmental niches or more pathogenic for humans. PMID:17559304

  11. Conversion disorder: a problematic diagnosis.

    PubMed

    Nicholson, Timothy R J; Stone, Jon; Kanaan, Richard A A

    2011-11-01

    The diagnosis of conversion disorder is problematic. Since doctors have conceptually and practically differentiated the symptoms from neurological ('organic') disease it has been presumed to be a psychological disorder, but the psychological mechanism, and how this differs from feigning (conscious simulation), has remained elusive. Although misdiagnosis of neurological disease as conversion disorder is uncommon, it remains a concern for clinicians, particularly for psychiatrists who may be unaware of the positive ways in which neurologists can exclude organic disease. The diagnosis is anomalous in psychiatry in that current diagnostic systems require that feigning is excluded and that the symptoms can be explained psychologically. In practice, feigning is very difficult to either disprove or prove, and a psychological explanation cannot always be found. Studies of childhood and adult psychological precipitants have tended to support the relevance of stressful life events prior to symptom onset at the group level but they are not found in a substantial proportion of cases. These problems highlight serious theoretical and practical issues not just for the current diagnostic systems but for the concept of the disorder itself. Psychology, physiology and functional imaging techniques have been used in attempts to elucidate the neurobiology of conversion disorder and to differentiate it from feigning, but while intriguing results are emerging they can only be considered preliminary. Such work looks to a future that could refine our understanding of the disorder. However, until that time, the formal diagnostic requirement for associated psychological stressors and the exclusion of feigning are of limited clinical value. Simplified criteria are suggested which will also encourage cooperation between neurology and psychiatry in the management of these patients.

  12. Algal Energy Conversion and Capture

    NASA Astrophysics Data System (ADS)

    Hazendonk, P.

    2015-12-01

    We address the potential for energy conversions and capture for: energy generation; reduction in energy use; reduction in greenhouse gas emissions; remediation of water and air pollution; protection and enhancement of soil fertility. These processes have the potential to sequester carbon at scales that may have global impact. Energy conversion and capture strategies evaluate energy use and production from agriculture, urban areas and industries, and apply existing and emerging technologies to reduce and recapture energy embedded in waste products. The basis of biocrude production from Micro-algal feedstocks: 1) The nutrients from the liquid fraction of waste streams are concentrated and fed into photo bioreactors (essentially large vessels in which microalgae are grown) along with CO2 from flue gasses from down stream processes. 2) The algae are processed to remove high value products such as proteins and beta-carotenes. The advantage of algae feedstocks is the high biomass productivity is 30-50 times that of land based crops and the remaining biomass contains minimal components that are difficult to convert to biocrude. 3) The remaining biomass undergoes hydrothermal liquefaction to produces biocrude and biochar. The flue gasses of this process can be used to produce electricity (fuel cell) and subsequently fed back into the photobioreactor. The thermal energy required for this process is small, hence readily obtained from solar-thermal sources, and furthermore no drying or preprocessing is required keeping the energy overhead extremely small. 4) The biocrude can be upgraded and refined as conventional crude oil, creating a range of liquid fuels. In principle this process can be applied on the farm scale to the municipal scale. Overall, our primary food production is too dependent on fossil fuels. Energy conversion and capture can make food production sustainable.

  13. Requirements for Hybrid Cosimulation

    DTIC Science & Technology

    2014-08-16

    zero. There is no mechanism in FMI 2.0 to skip microstep zero. The Ptolemy II Continuous director [18], which implements hybrid system simulation, also...step if Ptolemy II is the host simulator. But even if the future hybrid cosimulation standard does provide a mechanism to advance from communi- cation...Modelica Association, 2009. 24 [18] C. Ptolemaeus, editor. System Design, Modeling, and Simulation using Ptolemy II. Ptolemy.org, Berkeley, CA, 2014

  14. Energy conversion and storage process

    SciTech Connect

    Salmon, O.N.

    1982-01-26

    An energy conversion process is described for converting thermal energy into stored electrochemical energy and then into electrical energy comprising heating a first FeCl2-containing electrolyte melt to produce gaseous FeCl3 and a reductant product in a first chemical reaction, these reaction products being separated, cooled, optionally stored, and combined in a second FeCl2-containing electrolyte melt to cause a reaction to take place which is the reverse of said first reaction, thereby regenerating said first melt and producing heat and electrical energy.

  15. Formation of alcohol conversion catalysts

    DOEpatents

    Wachs, Israel E.; Cai, Yeping

    2001-01-01

    The method of the present invention involves a composition containing an intimate mixture of (a) metal oxide support particles and (b) a catalytically active metal oxide from Groups VA, VIA, or VIIA, its method of manufacture, and its method of use for converting alcohols to aldehydes. During the conversion process, catalytically active metal oxide from the discrete catalytic metal oxide particles migrates to the oxide support particles and forms a monolayer of catalytically active metal oxide on the oxide support particle to form a catalyst composition having a higher specific activity than the admixed particle composition.

  16. Power enhanced frequency conversion system

    NASA Technical Reports Server (NTRS)

    Sanders, Steven (Inventor); Lang, Robert J. (Inventor); Waarts, Robert G. (Inventor)

    2001-01-01

    A frequency conversion system includes at least one source providing a first near-IR wavelength output including a gain medium for providing high power amplification, such as double clad fiber amplifier, a double clad fiber laser or a semiconductor tapered amplifier to enhance the power output level of the near-IR wavelength output. The NFM device may be a difference frequency mixing (DFM) device or an optical parametric oscillation (OPO) device. Pump powers are gain enhanced by the addition of a rare earth amplifier or oscillator, or a Ra-man/Brillouin amplifier or oscillator between the high power source and the NFM device.

  17. Conversion of raw carbonaceous fuels

    DOEpatents

    Cooper, John F.

    2007-08-07

    Three configurations for an electrochemical cell are utilized to generate electric power from the reaction of oxygen or air with porous plates or particulates of carbon, arranged such that waste heat from the electrochemical cells is allowed to flow upwards through a storage chamber or port containing raw carbonaceous fuel. These configurations allow combining the separate processes of devolatilization, pyrolysis and electrochemical conversion of carbon to electric power into a single unit process, fed with raw fuel and exhausting high BTU gases, electric power, and substantially pure CO.sub.2 during operation.

  18. Raster to Lineal Conversion Software.

    DTIC Science & Technology

    1980-10-01

    Acceso B-i APPENDIX C NTIS GAIC-i r-l TAB U1nunno~Ced 1 just if icai DistribUtionI _Availabilit oe --- Avail and/or _it Spe ci I pca LIST OF FIGURES...shortcomings of the existing Raster to Lineal Conversion Software, and, secondly, to design and implement output modules to provide multiple output formats...the RAPS scanner and to provide flexibility. This would result in a more useful system, one that could provide multiple types of output from multiple

  19. Low conversion ratio fuel studies.

    SciTech Connect

    Smith, M. A.

    2006-02-28

    Recent studies on TRU disposition in fast reactors indicated viable reactor performance for a sodium cooled low conversion ratio reactor design. Additional studies have been initiated to refine the earlier work and consider the feasibility of alternate fuel forms such as nitride and oxide fuel (rather than metal fuel). These alternate fuel forms may have significant impacts upon the burner design and the safety behavior. The work performed thus far has focused on compiling the necessary fuel form property information and refinement of the physics models. For this limited project, the burner design and performance using nitride fuel will be assessed.

  20. Systems for hybrid cars

    NASA Astrophysics Data System (ADS)

    Bitsche, Otmar; Gutmann, Guenter

    Not only sharp competition but also legislation are pushing development of hybrid drive trains. Based on conventional internal combustion engine (ICE) vehicles, these drive trains offer a wide range of benefits from reduced fuel consumption and emission to multifaceted performance improvements. Hybrid electric drive trains may also facilitate the introduction of fuel cells (FC). The battery is the key component for all hybrid drive trains, as it dominates cost and performance issues. The selection of the right battery technology for the specific automotive application is an important task with an impact on costs of development and use. Safety, power, and high cycle life are a must for all hybrid applications. The greatest pressure to reduce cost is in soft hybrids, where lead-acid embedded in a considerate management presents the cheapest solution, with a considerable improvement in performance needed. From mild to full hybridization, an improvement in specific power makes higher costs more acceptable, provided that the battery's service life is equivalent to the vehicle's lifetime. Today, this is proven for the nickel-metal hydride system. Lithium ion batteries, which make use of a multiple safety concept, and with some development anticipated, provide even better prospects in terms of performance and costs. Also, their scalability permits their application in battery electric vehicles—the basis for better performance and enhanced user acceptance. Development targets for the batteries are discussed with a focus on system aspects such as electrical and thermal management and safety.