WorldWideScience

Sample records for multiple energy carrier

  1. The energy carrier hydrogen

    Anon.

    1992-01-01

    The potential of hydrogen to be used as a clean fuel for the production of heat and power, as well as for the propulsion of aeroplanes and vehicles, is described, in particular for Germany. First, attention is paid to the application of hydrogen as a basic material for the (petro)chemical industry, as an indirect energy source for (petro)chemical processes, and as a direct energy source for several purposes. Than the importance of hydrogen as an energy carrier in a large-scale application of renewable energy sources is discussed. Next an overview is given of new and old hydrogen production techniques from fossil fuels, biomass, or the electrolysis of water. Energetic applications of hydrogen in the transportation sector and the production of electric power and heat are mentioned. Brief descriptions are given of techniques to store hydrogen safely. Finally attention is paid to hydrogen research in Germany. Two hydrogen projects, in which Germany participates, are briefly dealt with: the Euro-Quebec project (production of hydrogen by means of hydropower), and the HYSOLAR project (hydrogen production by means of solar energy). 18 figs., 1 tab., 7 refs

  2. The energy-carriers

    Van Rensburg, W.C.J.

    1975-01-01

    Mining, processing and transport of minerals use the major proportion of South Africas total energy in various forms. With the Republic committed to expand these activities very substantially, will the necessary energy in the right forms be available

  3. Carrier multiplication in silicon nanocrystals: ab initio results

    Ivan Marri

    2015-02-01

    Full Text Available One of the most important goals in the field of renewable energy is the development of original solar cell schemes employing new materials to overcome the performance limitations of traditional solar cell devices. Among such innovative materials, nanostructures have emerged as an important class of materials that can be used to realize efficient photovoltaic devices. When these systems are implemented into solar cells, new effects can be exploited to maximize the harvest of solar radiation and to minimize the loss factors. In this context, carrier multiplication seems one promising way to minimize the effects induced by thermalization loss processes thereby significantly increasing the solar cell power conversion. In this work we analyze and quantify different types of carrier multiplication decay dynamics by analyzing systems of isolated and coupled silicon nanocrystals. The effects on carrier multiplication dynamics by energy and charge transfer processes are also discussed.

  4. Wuestite - a solar energy carrier

    Weidenkaff, A; Nueesch, P; Wokaun, A [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Reller, A [Hamburg Univ., Hamburg (Germany)

    1997-06-01

    Hydrogen is produced when Wuestite (Fe{sub 1-y}O) is oxidised by water. This reaction is part of a two-step thermochemical metal oxide cycle for the storage of solar energy in the form of chemical energy carriers, characterised by a high chemical potential. The reaction was studied in a tubular furnace with on-line gas analysis and further characterised in detail by DTA und high-temperature X-ray powder diffraction. The influence of non-stoichiometry, morphology and temperature on the mechanism and kinetics of the water-splitting reaction was determined. (author) 3 figs., tabs., 3 refs.

  5. Methanol as an energy carrier

    Biedermann, P.; Grube, T.; Hoehlein, B. (eds.)

    2006-07-01

    For the future, a strongly growing energy demand is expected in the transport sector worldwide. Economically efficient oil production will run through a maximum in the next decade. Higher fuel prices and an environmentally desirable reduction of emissions will increase the pressure for reducing fuel consumption and emissions in road traffic. These criteria show the urgent necessity of structural changes in the fuel market. Due to its advantages concerning industrial-scale production, storage and global availability, methanol has the short- to medium-term potential for gaining increased significance as a substitution product in the energy market. Methanol can be produced both from fossil energy sources and from biomass or waste materials through the process steps of synthesis gas generation with subsequent methanol synthesis. Methanol has the potential to be used in an environmentally friendly manner in gasoline/methanol mixtures for flexible fuel vehicles with internal combustion engines and in diesel engines with pure methanol. Furthermore, it can be used in fuel cell vehicles with on-board hydrogen production in direct methanol fuel cell drives, and in stationary systems for electricity and heat generation as well as for hydrogen production. Finally, in portable applications it serves as an energy carrier for electric power generation. In this book, the processes for the production and use of methanol are presented and evaluated, markets and future options are discussed and issues of safety and environmental impacts are addressed by a team of well-known authors. (orig.)

  6. Energy carriers in Norway; Energibaerere i Norge

    2008-01-15

    Within the Norwegian energy consumption, electricity is by far the most dominant energy carrier. In the last thirty years electricity has had an increased significance, while oil has been reduce. A trend that is likely to continue. Energy politics has among others these objectives: environment, reliability of supply and effective energy supply. These objectives are somewhat contradictory. In agreement with the environmental politic phasing out oil leads to a reduction in greenhouse gases. However this politic will have a local impact only effecting Norway, in a larger European connection it might lead to a larger net emission of CO{sub 2}. A political intervention in the energy market might also lead to a reduction in the energy markets effectiveness and flexibility. This report addresses this problem: If a total phase out of the stationary oil consumption is conducted, what energy carriers will this consumption convert to?

  7. Nuclear primary energy carriers. Short version

    Jaeck, W

    1978-04-01

    Basing on our present knowledge the following energy sources for energy supply must be taken into consideration in the long term: regenerative energy sources, fission energy gained by breeder reactors, nuclear fusion. While regenerative energy sources were treated at full length in the study 'Energy Sources for Tomorrow' the present study specifies the other two energy options. The availability and the reliability of nuclear primary energy carrier supply is described in detail and the conversion systems available or still being developed are investigated with regard to their specific consumption of primary energy. Topical questions concerning the proliferation stability of the fuel cycles and techniques are subject to the INFCE program. With reference to the nuclear energy documentation activities of the Federal Government this study is supposed to supply further fundamental material on nuclear primary energy carriers, consumption and readiness for application. Thus it will contribute to the question: 'Is nuclear energy an option which guarantees energy supply in the long term for the Federal Republic of Germany'. (orig.) 891 UA 892 ARA.

  8. Nuclear primary energy carriers. Pt. 1

    1978-04-01

    Basing on our present knowledge the following energy sources for energy supply must be taken into consideration in the long term: regenerative energy sources, fission energy gained by breeder reactors, nuclear fusion. While regenerative energy sources were treated at full length in the study 'Energy Sources for tomorrow' the present study specifies the other two energy options. The availability and the reliability of nuclear primary energy carrier supply is described in detail and the conversion systems available or still being developed are investigated with regard to their specific consumption of primary energy. Topical questions concerning the proliferation stability of the fuel cycles and techniques are subject to the INFCE programme. With reference to the nuclear energy documentation activities of the Federal Govenment this study is supposed to supply further fundamental material on nuclear primary energy carriers, consumption and readiness for application. Thus it will contribute to the question: 'Is nuclear energy an option which guarantees energy supply in the long term for the Federal Republic of Germany'. (orig.) [de

  9. Competitive position of energy carriers in trade

    Suding, P.H.; Forsbach, H.H.

    Industrial consumers and public institutions, which are classed with the group of minor consumers, differ in their behaviour in energy consumption greatly from the structure of the whole group. Also the willingness to convert from fuel oil to natural gas in these trade groups is relatively high. Within the framework of 5 model enterprises, the profitability of energy carriers and economizing technology in trade is analysed. The model enterprises are a bakery, a meat purveyor, a restaurant, a laundry and a hospital. The basic data are compared with the data from 1985. The comparison shows that the competitive positions of energy carriers in business and public in the process heat sector here not changed dramatically. The competitiveness of natural gas has improved since 1985 through the changes in price. However, in the sectors in which it belongs to the group of economical alternatives (e.g. in the bakeries), electricity has not lost much ground. (BR)

  10. Hydrogen, an energy carrier with a future

    Zimmer, K.H.

    1975-01-01

    The inefficient use, associated with pollutants, of the fossil energy carriers coal, crude oil and natural gas, will deplete resources, if the energy demand increases exponentially, in the not-too-distant future. That is the reason why the hydrogen-energy concept gains in importance. This requires drastic changes in structure in a lot of technological fields. This task is only to be mastered if there is cooperation between all special fields, in order to facilitate the economical production, distribution and utilization of hydrogen. (orig.) [de

  11. Formic Acid as a Hydrogen Energy Carrier

    Eppinger, Jö rg; Huang, Kuo-Wei

    2016-01-01

    The high volumetric capacity (S3 g H-2/L) and its low toxicity and flammability under ambient conditions make formic acid a promising hydrogen energy carrier. Particularly, in the past decade, significant advancements have been achieved in catalyst development for selective hydrogen generation from formic acid. This Perspective highlights the advantages of this approach with discussions focused on potential applications in the transportation sector together with analysis of technical requirements, limitations, and costs.

  12. Formic Acid as a Hydrogen Energy Carrier

    Eppinger, Jorg

    2016-12-15

    The high volumetric capacity (S3 g H-2/L) and its low toxicity and flammability under ambient conditions make formic acid a promising hydrogen energy carrier. Particularly, in the past decade, significant advancements have been achieved in catalyst development for selective hydrogen generation from formic acid. This Perspective highlights the advantages of this approach with discussions focused on potential applications in the transportation sector together with analysis of technical requirements, limitations, and costs.

  13. Energy carriers within Europe: electricity and SNG

    Lucas, N J.D.

    1977-03-01

    The general aim of this paper is to make a case for substitute natural gas as an energy carrier with prospects for growth that are at least as good as those of electricity and a life expectancy as long as one can reasonably plan for. The bulk of the paper analyzes the determinants of commercial competition between SNG and electricity. Space heat is treated in detail because this is generally seen as the area in which rapid expansion of electricity sales is possible. The provision of process heat to industry is dealt with superficially. The principal conclusion is that, for space heating and some industrial process heating and over a wide range of future costs for fossil and nuclear fuels, SNG from the marginal source of bulk fuel will be of lower cost than electricity from an integrated system of nuclear generating stations and fossil-fired stations using the same marginal source of fossil fuel. This conclusion may be difficult to accept because it conflicts with intuition. In Europe now there is a good case for installing more nuclear plants if what is wanted is base-load power. There are also mines producing coal at higher cost than imported oil. The short-term economic pressure, therefore, is to install nuclear plants and retreat from coal. Moreover, natural gas from the North Sea and even LNG from distant sources is cheaper than SNG from indigenous coal is likely to be. If one believes that indigenous oil and gas will be available in large quantities, or if one believes it will be possible to import oil without difficulty or political risk, then it is right to ignore SNG as an energy carrier; but the fashionable perception of the future is that indigenous production and/or imports will be restricted by physical shortage or political constraint so that, at the margin, heat will be supplied from nuclear fuel. In these circumstances SNG appears a better carrier of energy for heat than electricity. (MCW)

  14. Efficient Steplike Carrier Multiplication in Percolative Networks of Epitaxially Connected PbSe Nanocrystals

    Kulkarni, A.; Evers, W.H.; Tomić, Stanko; Beard, Matthew C.; Vanmaekelbergh, Daniel; Siebbeles, L.D.A.

    2018-01-01

    Carrier multiplication (CM) is a process in which a single photon excites two or more electrons. CM is of interest to enhance the efficiency of a solar cell. Until now, CM in thin films and solar cells of semiconductor nanocrystals (NCs) has been found at photon energies well above the minimum

  15. Carrier multiplication and its reduction by photodoping in colloidal InAs quantum dots

    Pijpers, J. J. H.; Hendry, E.; Milder, M.T.W.; Fanciulli, R.; Savolainen, J.; Herek, J.L.; Vanmaekelbergh, D.A.M.|info:eu-repo/dai/nl/304829137; Ruhman, S.; Mocatta, D.; Oron, D.; Aharoni, A.; Banin, U.; Bonn, M.

    2007-01-01

    Carrier (exciton) multiplication in colloidal InAs/CdSe/ZnSe core-shell quantum dots (QDs) is investigated using terahertz time-domain spectroscopy, time-resolved transient absorption, and quasi-continuous wave excitation spectroscopy. For excitation by high-energy photons (~2.7 times the band gap

  16. Multiple-level defect species evaluation from average carrier decay

    Debuf, Didier

    2003-10-01

    An expression for the average decay is determined by solving the the carrier continuity equations, which include terms for multiple defect recombination. This expression is the decay measured by techniques such as the contactless photoconductance decay method, which determines the average or volume integrated decay. Implicit in the above is the requirement for good surface passivation such that only bulk properties are observed. A proposed experimental configuration is given to achieve the intended goal of an assessment of the type of defect in an n-type Czochralski-grown silicon semiconductor with an unusually high relative lifetime. The high lifetime is explained in terms of a ground excited state multiple-level defect system. Also, minority carrier trapping is investigated.

  17. Ultrafast collinear scattering and carrier multiplication in graphene.

    Brida, D; Tomadin, A; Manzoni, C; Kim, Y J; Lombardo, A; Milana, S; Nair, R R; Novoselov, K S; Ferrari, A C; Cerullo, G; Polini, M

    2013-01-01

    Graphene is emerging as a viable alternative to conventional optoelectronic, plasmonic and nanophotonic materials. The interaction of light with charge carriers creates an out-of-equilibrium distribution, which relaxes on an ultrafast timescale to a hot Fermi-Dirac distribution, that subsequently cools emitting phonons. Although the slower relaxation mechanisms have been extensively investigated, the initial stages still pose a challenge. Experimentally, they defy the resolution of most pump-probe setups, due to the extremely fast sub-100 fs carrier dynamics. Theoretically, massless Dirac fermions represent a novel many-body problem, fundamentally different from Schrödinger fermions. Here we combine pump-probe spectroscopy with a microscopic theory to investigate electron-electron interactions during the early stages of relaxation. We identify the mechanisms controlling the ultrafast dynamics, in particular the role of collinear scattering. This gives rise to Auger processes, including charge multiplication, which is key in photovoltage generation and photodetectors.

  18. Renewable energy carriers: Hydrogen or liquid air/nitrogen?

    Li Yongliang; Chen Haisheng; Zhang Xinjing; Tan Chunqing; Ding Yulong

    2010-01-01

    The world's energy demand is met mainly by the fossil fuels today. The use of such fuels, however, causes serious environmental issues, including global warming, ozone layer depletion and acid rains. A sustainable solution to the issues is to replace the fossil fuels with renewable ones. Implementing such a solution, however, requires overcoming a number of technological barriers including low energy density, intermittent supply and mobility of the renewable energy sources. A potential approach to overcoming these barriers is to use an appropriate energy carrier, which can store, transport and distribute energy. The work to be reported in this paper aims to assess and compare a chemical energy carrier, hydrogen, with a physical energy carrier, liquid air/nitrogen, and discuss potential applications of the physical carrier. The ocean energy is used as an example of the renewable energy sources in the work. The assessment and comparison are carried out in terms of the overall efficiency, including production, storage/transportation and energy extraction. The environmental impact, waste heat recovery and safety issues are also considered. It is found that the physical energy carrier may be a better alternative to the chemical energy carrier under some circumstances, particularly when there are waste heat sources.

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

    Strandberg, Rune

    2015-01-01

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

  20. Hydrogen as an energy carrier. 2. rev. and enlarged ed.

    Winter, C.J.; Nitsch, J.

    1991-01-01

    This book deals with the possibilities of an energetic utilisation of hydrogen. This energy carrier can be produced from the unlimited energy sources - solar energy, wind energy and hydropower - and from nuclear energy. It is also capable of one day supplementing or superseding the fossil energy carriers oil, coal and gas. What is special about the book is that it goes beyond a mere physical/technical description to discuss the economic and political aspects and ecological effects and requirements that are an essential part of sound energy planning today. Thus, the authors and editors outline the step-by-step development of a hydrogen economy, mainly based on solar energy, providing a solution to both the pollution problems caused by the use of fossil energy carriers and the energy requirements of the third world. (orig.) With 197 figs., 71 tabs

  1. A novel velocity estimator using multiple frequency carriers

    Zhang, Zhuo; Jakobsson, Andreas; Nikolov, Svetoslav

    2004-01-01

    . In this paper, we propose a nonlinear least squares (NLS) estimator. Typically, NLS estimators are computationally cumbersome, in general requiring the minimization of a multidimensional and often multimodal cost function. Here, by noting that the unknown velocity will result in a common known frequency......Most modern ultrasound scanners use the so-called pulsed-wave Doppler technique to estimate the blood velocities. Among the narrowband-based methods, the autocorrelation estimator and the Fourier-based method are the most commonly used approaches. Due to the low level of the blood echo, the signal......-to-noise ratio is low, and some averaging in depth is applied to improve the estimate. Further, due to velocity gradients in space and time, the spectrum may get smeared. An alternative approach is to use a pulse with multiple frequency carriers, and do some form of averaging in the frequency domain. However...

  2. Interlayer electron-hole pair multiplication by hot carriers in atomic layer semiconductor heterostructures

    Barati, Fatemeh; Grossnickle, Max; Su, Shanshan; Lake, Roger; Aji, Vivek; Gabor, Nathaniel

    Two-dimensional heterostructures composed of atomically thin transition metal dichalcogenides provide the opportunity to design novel devices for the study of electron-hole pair multiplication. We report on highly efficient multiplication of interlayer electron-hole pairs at the interface of a tungsten diselenide / molybdenum diselenide heterostructure. Electronic transport measurements of the interlayer current-voltage characteristics indicate that layer-indirect electron-hole pairs are generated by hot electron impact excitation. Our findings, which demonstrate an efficient energy relaxation pathway that competes with electron thermalization losses, make 2D semiconductor heterostructures viable for a new class of hot-carrier energy harvesting devices that exploit layer-indirect electron-hole excitations. SHINES, an Energy Frontier Research Center funded by the U.S. Department of Energy, Air Force Office of Scientific Research.

  3. Perspective on the prospects of a carrier multiplication nanocrystal solar cell.

    Nair, Gautham; Chang, Liang-Yi; Geyer, Scott M; Bawendi, Moungi G

    2011-05-11

    This article presents a perspective on the experimental and theoretical work to date on the efficiency of carrier multiplication (CM) in colloidal semiconductor nanocrystals (NCs). Early reports on CM in NCs suggested large CM efficiency enhancements. However, recent experiments have shown that CM in nanocrystalline samples is not significantly stronger, and often is weaker, than in the parent bulk when compared on an absolute photon energy basis. This finding is supported by theoretical consideration of the CM process and the competing intraband relaxation. We discuss the experimental artifacts that may have led to the apparently strong CM estimated in early reports. The finding of bulklike CM in NCs suggests that the main promise of quantum confinement is to boost the photovoltage at which carriers can be extracted. With this in mind, we discuss research directions that may result in effective use of CM in a solar cell.

  4. Overview of levies on energy carriers in Europe

    Iten, R.; Gehrig, S.; Koenig, Ch.

    2000-01-01

    This short report for the Swiss Federal Office of Energy (SFOE) examines the situation with respect to levies and steering taxes on various forms of energy in European countries. Comparisons are made with the situation in Switzerland regarding energy prices for various consumer groups, taxation of energy carriers and exceptions for energy-intensive industries. Details are given on prices of energy and the levies imposed, in particular with respect to carbon taxes. Data are given for 11 European countries and detailed information on regulations concerning exceptions is presented for selected countries. Finally, fuel price differences between neighbouring countries are examined and the role of 'motor-fuel-tourism' is discussed

  5. The potential of (waste)water as energy carrier

    Frijns, Jos; Hofman, Jan; Nederlof, Maarten

    2013-01-01

    Graphical abstract: Energy input and potential output of the Dutch communal water cycle. Highlights: ► Municipal wastewater is a large carrier of chemical and thermal energy. ► The recovery of chemical energy from wastewater can be maximised by digestion. ► The potential of thermal energy recovery from wastewater is huge. ► Underground thermal energy storage is a rapidly developing renewable energy source. - Abstract: Next to energy efficiency improvements in the water sector, there is a need for new concepts in which water is viewed as a carrier of energy. Municipal wastewater is a potential source of chemical energy, i.e. organic carbon that can be recovered as biogas in sludge digestion. The recovery of chemical energy can be maximised by up-concentration of organic carbon and maximised sludge digestion or by source separation and anaerobic treatment. Even more so, domestic wastewater is a source of thermal energy. Through warm water conservation and heat recovery, for example with shower heat exchangers, substantial amounts of energy can be saved and recovered from the water cycle. Water can also be an important renewable energy source, i.e. as underground thermal energy storage. These systems are developing rapidly in the Netherlands and their energy potential is large.

  6. Terahertz study of ultrafast carrier dynamics in InGa/GaN multiple quantum wells

    Porte, Henrik; Turchinovich, Dmitry; Cooke, David

    2009-01-01

    Ultrafast carrier dynamics in InGaN/GaN multiple quantum wells is measured by time-resolved terahertz spectroscopy. The built-in piezoelectric field is initially screened by photoexcited, polarized carriers, and is gradullay restored as the carriers recombine. We observe a nonexponential decay...... of the carrier density. Time-integrated photoluminescence spectra have shown a complete screening of the built-in piezoelectric field at high excitation fluences. We also observe that the terahertz conductivity spectra differs from simple Drude conductivity, describing the response of free carriers, and are well...

  7. Nuclear primary energy carriers. Pt. 2

    1978-04-01

    A very brief presentation of the elementary fusion reactions, the energies delivered by them and the most basic energy balances leading to Lawsontype diagrams are given. The reserves and cost of lithium and deuterium, gives estimates of the total available from DT fusion and comments on production technology, availability and handling of the fuels are outlined. A survey is given of the different concepts of magnetic confinement (stellarators, tokamaks, toroidal pinches, mirror machines, two-component plasmas), of confinement by walls, gas blankets and imploding liners and, finally, of the concepts of inertial confinement (laser fusion, beam fusion). The reactors designed or outlined on the basis of the tokamak, high-β, mirror, and laser fusion concepts are presented, which is followed by a discussion of the key problems of fusion power plants. The main reqirements on the superconducting magnet system for possible fusion reactors, particularly tokamak reactors, are discussed and compared with the present state of the superconducting magent technology. The present-day knowledge of the cost structure of fusion power plants and the sensitivity of this structure with respect to the physical and technical assumptions made is analysed. Finally the aspects of safety and environment are treated. The problems discussed include the hazard potentials of different designs (radiological, toxicological, and with respect to stored energies), release of radioactivity, possible kinds of malfunctioning, and the environmental impact of waste heat, radiation and radioactive waste. (orig.) [de

  8. Biomass-based energy carriers in the transportation sector

    Johansson, Bengt.

    1995-03-01

    The purpose of this report is to study the technical and economic prerequisites to attain reduced carbon dioxide emissions through the use of biomass-based energy carriers in the transportation sector, and to study other environmental impacts resulting from an increased use of biomass-based energy carriers. CO 2 emission reduction per unit arable and forest land used for biomass production (kg CO 2 /ha,year) and costs for CO 2 emission reduction (SEK/kg CO 2 ) are estimated for the substitution of gasoline and diesel with rape methyl ester, biogas from lucerne, ethanol from wheat and ethanol, methanol, hydrogen and electricity from Salix and logging residues. Of the studied energy carriers, those based on Salix provide the largest CO 2 emission reduction. In a medium long perspective, the costs for CO 2 emission reduction seem to be lowest for methanol from Salix and logging residues. The use of fuel cell vehicles, using methanol or hydrogen as energy carriers, can in a longer perspective provide more energy efficient utilization of biomass for transportation than the use of internal combustion engine vehicles. 136 refs, 12 figs, 25 tabs

  9. Efficient Steplike Carrier Multiplication in Percolative Networks of Epitaxially Connected PbSe Nanocrystals.

    Kulkarni, Aditya; Evers, Wiel H; Tomić, Stanko; Beard, Matthew C; Vanmaekelbergh, Daniel; Siebbeles, Laurens D A

    2018-01-23

    Carrier multiplication (CM) is a process in which a single photon excites two or more electrons. CM is of interest to enhance the efficiency of a solar cell. Until now, CM in thin films and solar cells of semiconductor nanocrystals (NCs) has been found at photon energies well above the minimum required energy of twice the band gap. The high threshold of CM strongly limits the benefits for solar cell applications. We show that CM is more efficient in a percolative network of directly connected PbSe NCs. The CM threshold is at twice the band gap and increases in a steplike fashion with photon energy. A lower CM efficiency is found for a solid of weaker coupled NCs. This demonstrates that the coupling between NCs strongly affects the CM efficiency. According to device simulations, the measured CM efficiency would significantly enhance the power conversion efficiency of a solar cell.

  10. Multiplicities in high energy interactions

    Derrick, M.

    1984-01-01

    Charged particle multiplicities in hadronic collision have been measured for all energies up to √s = 540 GeV in the center of mass. Similar measurements in e + e - annihilation cover the much smaller range - up to √s = 40 GeV. Data are also available from deep inelastic neutrino scattering up to √s approx. 10 GeV. The experiments measure the mean charged multiplicity , the rapidity density at y = O, and the distributions in prong number. The mean number of photons associated with the events can be used to measure the π 0 and eta 0 multiplicities. Some information is also available on the charged pion, kaon, and nucleon fractions as well as the K 0 and Λ 0 rates and for the higher energy data, the identically equal fraction. We review this data and consider the implications of extrapolations to SSC energies. 13 references

  11. High power terahertz induced carrier multiplication in Silicon

    Tarekegne, Abebe Tilahun; Pedersen, Pernille Klarskov; Iwaszczuk, Krzysztof

    2015-01-01

    The application of an intense THz field results a nonlinear transmission in high resistivity silicon. Upon increasing field strength, the transmission falls from 70% to 62% due to carrier generation through THz-induced impact ionization and subsequent absorption of the THz field by free electrons....

  12. Ultrafast carrier dynamics in InGaN/GaN multiple quantum wells

    Porte, Henrik; Turchinovich, Dmitry; Cooke, David

    We studied the THz conductivity of InGaN/GaN multiple quantum wells (MQWs)by time-resolved terahertz spectroscopy. A nonexponential carrier density decay is observed due to the restoration of a built-in piezoelectric field. Terahertz conductivity spectra show a nonmetallic behavior of the carriers....

  13. Engineering of lead chalcogenide nanostructures for carrier multiplication: Core/shell, 1D, and 2D

    Lin, Qianglu

    Near infrared emitting semiconductors have been used widely in industry especially in solar-cell fabrications. The efficiency of single junction solar-cell can reach the Shockley-Queisser limit by using optimum band gap material such as silicon and cadmium telluride. The theoretical efficiency can be further enhanced through carrier multiplication, in which a high energy photon is absorbed and more than one electron-hole pair can be generated, reaching more than 100% quantum efficiency in the high energy region of sunlight. The realization of more than unity external quantum efficiency in lead selenide quantum dots solar cell has motivated vast investigation on lowering the carrier multiplication threshold and further improving the efficiency. This dissertation focuses on synthesis of lead chalcogenide nanostructures for their optical spectroscopy studies. PbSe/CdSe core/shell quantum dots were synthesized by cation exchange to obtain thick shells (up to 14 monolayers) for studies of visible and near infrared dual band emissions and carrier multiplication efficiency. By examining the reaction mechanism, a thermodynamic and a kinetic model are introduced to explain the vacancy driven cation exchange. As indicated by the effective mass model, PbSe/CdSe core/shell quantum dots has quasi-type-II band alignment, possessing electron delocalized through the entire quantum dot and hole localized in the core, which breaks down the symmetry of energy levels in the conduction and valence band, leading to hot-hole-assisted efficient multi-exciton generation and a lower carrier multiplication threshold to the theoretical value. For further investigation of carrier multiplication study, PbTe, possessing the highest efficiency among lead chalcogenides due to slow intraband cooling, is synthesized in one-dimensional and two-dimensional nanostructures. By using dodecanethiol as the surfactant, PbTe NRs can be prepared with high uniformity in width and resulted in fine quantum

  14. A Novel Power-Saving Transmission Scheme for Multiple-Component-Carrier Cellular Systems

    Yao-Liang Chung

    2016-04-01

    Full Text Available As mobile data traffic levels have increased exponentially, resulting in rising energy costs in recent years, the demand for and development of green communication technologies has resulted in various energy-saving designs for cellular systems. At the same time, recent technological advances have allowed multiple component carriers (CCs to be simultaneously utilized in a base station (BS, a development that has made the energy consumption of BSs a matter of increasing concern. To help address this concern, herein we propose a novel scheme aimed at efficiently minimizing the power consumption of BS transceivers during transmission, while still ensuring good service quality and fairness for users. Specifically, the scheme utilizes the dynamic activation/deactivation of CCs during data transmission to increase power usage efficiency. To test its effectiveness, the proposed scheme was applied to a model consisting of a BS with orthogonal frequency division multiple access-based CCs in a downlink transmission environment. The results indicated that, given periods of relatively light traffic loads, the total power consumption of the proposed scheme is significantly lower than that of schemes in which all the CCs of a BS are constantly activated, suggesting the scheme’s potential for reducing both energy costs and carbon dioxide emissions.

  15. Conditions for a carrier multiplication in amorphous-selenium based photodetector

    Masuzawa, Tomoaki; Kuniyoshi, Shingo; Onishi, Masanori; Kato, Richika; Saito, Ichitaro; Okano, Ken [Department of Material Science, International Christian University, S102 Science Hall, ICU, 3-10-2 Osawa, Mitaka, Tokyo 181-8585 (Japan); Yamada, Takatoshi [Nanotube Research Center, National Institute of Advanced Industrial Science and Technology (AIST), AIST Tsukuba Central 5, Tsukuba, Ibaraki 305-8568 (Japan); Koh, Angel T. T.; Chua, Daniel H. C. [Department of Materials Science and Engineering, National University of Singapore, 7 Engineering Drive 1, Singapore 117574 (Singapore); Shimosawa, Tatsuo [Department of Clinical Laboratory, Faculty of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyoku, Tokyo 113-8655 (Japan)

    2013-02-18

    Amorphous selenium is a promising candidate for high sensitivity photodetector due to its unique carrier multiplication phenomenon. More than 10 carriers can be generated per incident photon, which leads to high photo-conversion efficiency of 1000% that allows real-time imaging in dark ambient. However, application of this effect has been limited to specific devices due to the lack in material characterization. In this article, mechanism of carrier multiplication has been clarified using time-of-flight secondary ion mass spectroscopy and Raman spectroscopy. A prototype photodetector achieved photo conversion efficiency of 4000%, which explains the signal enhancement mechanism in a-Se based photodetector.

  16. Conditions for a carrier multiplication in amorphous-selenium based photodetector

    Masuzawa, Tomoaki; Kuniyoshi, Shingo; Onishi, Masanori; Kato, Richika; Saito, Ichitaro; Okano, Ken; Yamada, Takatoshi; Koh, Angel T. T.; Chua, Daniel H. C.; Shimosawa, Tatsuo

    2013-01-01

    Amorphous selenium is a promising candidate for high sensitivity photodetector due to its unique carrier multiplication phenomenon. More than 10 carriers can be generated per incident photon, which leads to high photo-conversion efficiency of 1000% that allows real-time imaging in dark ambient. However, application of this effect has been limited to specific devices due to the lack in material characterization. In this article, mechanism of carrier multiplication has been clarified using time-of-flight secondary ion mass spectroscopy and Raman spectroscopy. A prototype photodetector achieved photo conversion efficiency of 4000%, which explains the signal enhancement mechanism in a-Se based photodetector.

  17. Production of chemical energy carriers by non-expendable energy sources

    Nitsch, J

    1976-01-01

    The different forms of energy (radiation, high-temperature heat and electricity) arising from non-expendable energy sources like solar energy can be used for the production of chemical energy-carriers. Possible methods are the splitting of water by means of photolysis, thermochemical cycles and electrolysis, as well as the storage of energy in closed loop chemical systems. These methods are described and efficiencies and costs of the production of these energy carriers are specified. Special problems of the long-distance transportation of hydrogen produced by solar energy are described and the resulting costs are estimated.

  18. Multiple carrier transport in N-face indium nitride

    Koblmueller, Gregor; Gallinat, Chad S.; Speck, James S.; Umana-Membreno, Gilberto A.; Nener, Brett D.; Parish, Giacinta; Fehlberg, Tamara B.

    2008-01-01

    We present temperature (20-300 K) dependent multi-carrier measurements of electron species in N-face indium nitride. N-face InN samples were grown to different thicknesses (500-2000 nm) via plasma-assisted molecular beam epitaxy on C-face SiC substrates. Surface and bulk electron transport properties were extracted using a quantitative mobility spectrum analysis. Mobility of both bulk and surface electron species increase with film thickness. The temperature dependence of the mobility of both species differs to that of In-polar samples studied previously, while the mobility of surface electrons is more than twice that of In-polar samples with only a slight corresponding reduction in sheet concentration. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  19. A Novel Algorithm for Efficient Downlink Packet Scheduling for Multiple-Component-Carrier Cellular Systems

    Yao-Liang Chung

    2016-11-01

    Full Text Available The simultaneous aggregation of multiple component carriers (CCs for use by a base station constitutes one of the more promising strategies for providing substantially enhanced bandwidths for packet transmissions in 4th and 5th generation cellular systems. To the best of our knowledge, however, few previous studies have undertaken a thorough investigation of various performance aspects of the use of a simple yet effective packet scheduling algorithm in which multiple CCs are aggregated for transmission in such systems. Consequently, the present study presents an efficient packet scheduling algorithm designed on the basis of the proportional fair criterion for use in multiple-CC systems for downlink transmission. The proposed algorithm includes a focus on providing simultaneous transmission support for both real-time (RT and non-RT traffic. This algorithm can, when applied with sufficiently efficient designs, provide adequate utilization of spectrum resources for the purposes of transmissions, while also improving energy efficiency to some extent. According to simulation results, the performance of the proposed algorithm in terms of system throughput, mean delay, and fairness constitute substantial improvements over those of an algorithm in which the CCs are used independently instead of being aggregated.

  20. The water footprint of energy consumption: an assessment of water requirements of primary energy carriers

    Gerbens-Leenes, P.W.; Hoekstra, A.Y.; Van der Meer, T.H.

    2007-01-01

    Gerbens-Leenes, P.W., Hoekstra, A.Y., Van der Meer, T.H., 2007. The water footprint of energy consumption: an assessment of water requirements of primary energy carriers. In: proceedings ‘First World Water Sustainability-Renewable Energy Congress and Exhibition’. 25-28 November 2007, Maastricht, the

  1. Carrier-carrier relaxation kinetics in quantum well semiconductor structures with nonparabolic energy bands

    Dery, H.; Tromborg, Bjarne; Eisenstein, G.

    2003-01-01

    We describe carrier-carrier scattering dynamics in an inverted quantum well structure including the nonparabolic nature of the valance band. A solution of the semiconductor Bloch equations yields strong evidence to a large change in the temporal evolution of the carrier distributions compared to ...

  2. Optimization of carrier multiplication for more effcient solar cells: the case of Sn quantum dots.

    Allan, Guy; Delerue, Christophe

    2011-09-27

    We present calculations of impact ionization rates, carrier multiplication yields, and solar-power conversion efficiencies in solar cells based on quantum dots (QDs) of a semimetal, α-Sn. Using these results and previous ones on PbSe and PbS QDs, we discuss a strategy to select QDs with the highest carrier multiplication rate for more efficient solar cells. We suggest using QDs of materials with a close to zero band gap and a high multiplicity of the bands in order to favor the relaxation of photoexcited carriers by impact ionization. Even in that case, the improvement of the maximum solar-power conversion efficiency appears to be a challenging task. © 2011 American Chemical Society

  3. Recombination in liquid filled ionisation chambers with multiple charge carrier species: Theoretical and numerical results

    Aguiar, P.; González-Castaño, D.M.; Gómez, F.; Pardo-Montero, J.

    2014-01-01

    Liquid-filled ionisation chambers (LICs) are used in radiotherapy for dosimetry and quality assurance. Volume recombination can be quite important in LICs for moderate dose rates, causing non-linearities in the dose rate response of these detectors, and needs to be corrected for. This effect is usually described with Greening and Boag models for continuous and pulsed radiation respectively. Such models assume that the charge is carried by two different species, positive and negative ions, each of those species with a given mobility. However, LICs operating in non-ultrapure mode can contain different types of electronegative impurities with different mobilities, thus increasing the number of different charge carriers. If this is the case, Greening and Boag models can be no longer valid and need to be reformulated. In this work we present a theoretical and numerical study of volume recombination in parallel-plate LICs with multiple charge carrier species, extending Boag and Greening models. Results from a recent publication that reported three different mobilities in an isooctane-filled LIC have been used to study the effect of extra carrier species on recombination. We have found that in pulsed beams the inclusion of extra mobilities does not affect volume recombination much, a behaviour that was expected because Boag formula for charge collection efficiency does not depend on the mobilities of the charge carriers if the Debye relationship between mobilities and recombination constant holds. This is not the case in continuous radiation, where the presence of extra charge carrier species significantly affects the amount of volume recombination. - Highlights: • Analytical extension of Greening and Boag theories to multiple charge carriers. • Detailed numerical study of process of volume recombination in LICs. • Recombination in pulsed beams is independent of number and mobilities of carriers. • Multiple charge carriers have a significant effect in continuous

  4. Research on energy efficiency design index for sea-going LNG carriers

    Lin, Yan; Yu, Yanyun; Guan, Guan

    2014-12-01

    This paper describes the characteristics of liquefied natural gas (LNG) carriers briefly. The LNG carrier includes power plant selection, vapor treatment, liquid cargo tank type, etc. Two parameters—fuel substitution rate and recovery of boil of gas (BOG) volume to energy efficiency design index (EEDI) formula are added, and EEDI formula of LNG carriers is established based on ship EEDI formula. Then, based on steam turbine propulsion device of LNG carriers, mathematical models of LNG carriers' reference line value are established in this paper. By verification, the EEDI formula of LNG carriers described in this paper can provide a reference for LNG carrier EEDI calculation and green shipbuilding.

  5. The prospects for hydrogen as an energy carrier: an overview of hydrogen energy and hydrogen energy systems

    Rosen, Marc A.; Koohi-Fayegh, Seama [Ontario Univ., Oshawa, ON (Canada). Inst. of Technology

    2016-02-15

    Hydrogen is expected to play a key role as an energy carrier in future energy systems of the world. As fossil-fuel supplies become scarcer and environmental concerns increase, hydrogen is likely to become an increasingly important chemical energy carrier and eventually may become the principal chemical energy carrier. When most of the world's energy sources become non-fossil based, hydrogen and electricity are expected to be the two dominant energy carriers for the provision of end-use services. In such a ''hydrogen economy,'' the two complementary energy carriers, hydrogen and electricity, are used to satisfy most of the requirements of energy consumers. A transition era will bridge the gap between today's fossil-fuel economy and a hydrogen economy, in which non-fossil-derived hydrogen will be used to extend the lifetime of the world's fossil fuels - by upgrading heavy oils, for instance - and the infrastructure needed to support a hydrogen economy is gradually developed. In this paper, the role of hydrogen as an energy carrier and hydrogen energy systems' technologies and their economics are described. Also, the social and political implications of hydrogen energy are examined, and the questions of when and where hydrogen is likely to become important are addressed. Examples are provided to illustrate key points. (orig.)

  6. The prospects for hydrogen as an energy carrier: an overview of hydrogen energy and hydrogen energy systems

    Rosen, Marc A.; Koohi-Fayegh, Seama

    2016-01-01

    Hydrogen is expected to play a key role as an energy carrier in future energy systems of the world. As fossil-fuel supplies become scarcer and environmental concerns increase, hydrogen is likely to become an increasingly important chemical energy carrier and eventually may become the principal chemical energy carrier. When most of the world's energy sources become non-fossil based, hydrogen and electricity are expected to be the two dominant energy carriers for the provision of end-use services. In such a ''hydrogen economy,'' the two complementary energy carriers, hydrogen and electricity, are used to satisfy most of the requirements of energy consumers. A transition era will bridge the gap between today's fossil-fuel economy and a hydrogen economy, in which non-fossil-derived hydrogen will be used to extend the lifetime of the world's fossil fuels - by upgrading heavy oils, for instance - and the infrastructure needed to support a hydrogen economy is gradually developed. In this paper, the role of hydrogen as an energy carrier and hydrogen energy systems' technologies and their economics are described. Also, the social and political implications of hydrogen energy are examined, and the questions of when and where hydrogen is likely to become important are addressed. Examples are provided to illustrate key points. (orig.)

  7. Preconception carrier screening for multiple disorders: evaluation of a screening offer in a Dutch founder population.

    Mathijssen, Inge B; Holtkamp, Kim C A; Ottenheim, Cecile P E; van Eeten-Nijman, Janneke M C; Lakeman, Phillis; Meijers-Heijboer, Hanne; van Maarle, Merel C; Henneman, Lidewij

    2018-02-01

    Technological developments have enabled carrier screening for multiple disorders. This study evaluated experiences with a preconception carrier screening offer for four recessive disorders in a Dutch founder population. Questionnaires were completed by 182 attendees pretesting and posttesting and by 137 non-attendees. Semistructured interviews were conducted with seven of the eight carrier couples. Attendees were mainly informed about the existence of screening by friends/colleagues (49%) and family members (44%). Familiarity with the genetic disorders was high. Knowledge after counseling increased (p influencers (family/friends) can be used to raise awareness of a screening offer. Our findings provide lessons for the implementation of expanded carrier screening panels in other communities and other settings.

  8. Empirical formulae for excess noise factor with dead space for single carrier multiplication

    Dehwah, Ahmad H.

    2011-09-01

    In this letter, two empirical equations are presented for the calculation of the excess noise factor of an avalanche photodiode for single carrier multiplication including the dead space effect. The first is an equation for calculating the excess noise factor when the multiplication approaches infinity as a function of parameters that describe the degree of the dead space effect. The second equation can be used to find the minimum value of the excess noise factor for any multiplication when the dead space effect is completely dominant, the so called "deterministic" limit. This agrees with the theoretically known equation for multiplications less than or equal to two. © 2011 World Scientific Publishing Company.

  9. Empirical formulae for excess noise factor with dead space for single carrier multiplication

    Dehwah, Ahmad H.; Ajia, Idris A.; Marsland, John S.

    2011-01-01

    In this letter, two empirical equations are presented for the calculation of the excess noise factor of an avalanche photodiode for single carrier multiplication including the dead space effect. The first is an equation for calculating the excess noise factor when the multiplication approaches infinity as a function of parameters that describe the degree of the dead space effect. The second equation can be used to find the minimum value of the excess noise factor for any multiplication when the dead space effect is completely dominant, the so called "deterministic" limit. This agrees with the theoretically known equation for multiplications less than or equal to two. © 2011 World Scientific Publishing Company.

  10. Ultrahigh energy gamma rays: carriers of cosmological information

    Aharonian, F.A.; Atoyan, A.M.

    1985-01-01

    Observational data being the basis of contemporary cosmological models are not numerous: Hubble law of redshift for galaxies, element abundances, and observation of cosmic microwave background radiation (MBR). The significance of MBR discovery predicted in the Big-Band model is particularly stressed. Radio astronomical measurements give an information on MBR only near the Earth. Experimental confirmation of evolution of MBR, i.e., its probing in remote epochs, might obviously present a direct verification of the hypothesis of hot expanding Universe. The carriers of similar cosmological information should be particles which, firstly, effectively interact with MBR, and secondly, make it possible to identify unambiguously the epoch of interaction. A possibility to verify a number of cosmological hypotheses by searching the cutoffs in spectra of ultrahigh energy gamma-rays (UHEGR) from extragalactic sources is discussed

  11. Photo-generated carriers lose energy during extraction from polymer-fullerene solar cells

    Melianas, Armantas

    2015-11-05

    In photovoltaic devices, the photo-generated charge carriers are typically assumed to be in thermal equilibrium with the lattice. In conventional materials, this assumption is experimentally justified as carrier thermalization completes before any significant carrier transport has occurred. Here, we demonstrate by unifying time-resolved optical and electrical experiments and Monte Carlo simulations over an exceptionally wide dynamic range that in the case of organic photovoltaic devices, this assumption is invalid. As the photo-generated carriers are transported to the electrodes, a substantial amount of their energy is lost by continuous thermalization in the disorder broadened density of states. Since thermalization occurs downward in energy, carrier motion is boosted by this process, leading to a time-dependent carrier mobility as confirmed by direct experiments. We identify the time and distance scales relevant for carrier extraction and show that the photo-generated carriers are extracted from the operating device before reaching thermal equilibrium.

  12. Comparative study of hydrogen and methanol as energy carriers

    Johansson, Anna

    1998-06-01

    This report has been written with the purpose to compare hydrogen and methanol, with gasoline, as energy carriers for new energy systems in the future. This energy system must satisfy the demands for sustainable development. The report focuses on motor vehicle applications. A few different criteria has been developed to help form the characterisation method. The criteria proposed in this thesis are developed for an environmental comparison mainly based on emissions from combustion. The criteria concerns the following areas: Renewable resources, The ozone layer, The greenhouse effect, The acidification, and Toxic substances. In many ways, hydrogen may seem as a very good alternative compared with gasoline and diesel oil. Combustion of hydrogen in air results in water and small amounts of oxides of nitrogen. In this report, hydrogen produced from renewable resources is investigated. This is necessary to fulfill the demands for sustainable development. Today, however, steam reforming of fossil fuels represent 99% of the hydrogen production market. Problem areas connected with hydrogen use are for instance storage and distribution. Methanol has many advantages, while comparing methanol and gasoline, like lower emissions of nitrogen oxides and hydrocarbons, limited emissions of carbon dioxide and no sulphur content. Methanol can be produced from many different resources, for example natural gas, naphtha, oil, coal or peat, and biomass. To meet demands for sustainable production, methanol has to be produced from biomass Examination paper. 32 refs, 20 figs, 13 tabs

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

    Schneemann, Matthias; Carius, Reinhard; Rau, Uwe [IEK5-Photovoltaics, Forschungszentrum Jülich, Jülich 52425 (Germany); Kirchartz, Thomas, E-mail: t.kirchartz@fz-juelich.de [IEK5-Photovoltaics, Forschungszentrum Jülich, Jülich 52425 (Germany); Faculty of Engineering and CENIDE, University of Duisburg-Essen, Carl-Benz-Str. 199, Duisburg 47057 (Germany)

    2015-05-28

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

  14. Methanol as an energy source and/or energy carrier in membrane processes

    Gallucci, F.; Basile, A.; Drioli, E.

    2007-01-01

    Methanol is commonly considered a hydrogen source and/or hydrogen carrier. In fact, methanol can be produced by partial oxidation of biomass and in this case it is considered a source for hydrogen and therefore for energy. It can also be produced from carbon dioxide and hydrogen; in this case, it

  15. A Suboptimal Power-Saving Transmission Scheme in Multiple Component Carrier Networks

    Chung, Yao-Liang; Tsai, Zsehong

    Power consumption due to transmissions in base stations (BSs) has been a major contributor to communication-related CO2 emissions. A power optimization model is developed in this study with respect to radio resource allocation and activation in a multiple Component Carrier (CC) environment. We formulate and solve the power-minimization problem of the BS transceivers for multiple-CC networks with carrier aggregation, while maintaining the overall system and respective users' utilities above minimum levels. The optimized power consumption based on this model can be viewed as a lower bound of that of other algorithms employed in practice. A suboptimal scheme with low computation complexity is proposed. Numerical results show that the power consumption of our scheme is much better than that of the conventional one in which all CCs are always active, if both schemes maintain the same required utilities.

  16. Cantilever piezoelectric energy harvester with multiple cavities

    S Srinivasulu Raju; M Umapathy; G Uma

    2015-01-01

    Energy harvesting employing piezoelectric materials in mechanical structures such as cantilever beams, plates, diaphragms, etc, has been an emerging area of research in recent years. The research in this area is also focused on structural tailoring to improve the harvested power from the energy harvesters. Towards this aim, this paper presents a method for improving the harvested power from a cantilever piezoelectric energy harvester by introducing multiple rectangular cavities. A generalized model for a piezoelectric energy harvester with multiple rectangular cavities at a single section and two sections is developed. A method is suggested to optimize the thickness of the cavities and the number of cavities required to generate a higher output voltage for a given cantilever beam structure. The performance of the optimized energy harvesters is evaluated analytically and through experimentation. The simulation and experimental results show that the performance of the energy harvester can be increased with multiple cavities compared to the harvester with a single cavity. (paper)

  17. Multiplicity distributions in high energy collisions

    Giovannini, A.; Lupia, S.; Ugoccioni, R.

    1992-01-01

    We discuss the important phases in the evolution of our understanding of multiplicity distributions in high energy collisions with particular emphasis to intermittent behavior and shoulder structure problem. (orig.)

  18. Multiplicity distributions in high energy collisions

    Giovannini, A.; Lupia, S.; Ugoccioni, R. (Dipt. di Fisica Teorica, Univ. Turin (Italy) INFN, Turin (Italy))

    1992-03-01

    We discuss the important phases in the evolution of our understanding of multiplicity distributions in high energy collisions with particular emphasis to intermittent behavior and shoulder structure problem. (orig.).

  19. Density Functional Theory Calculations of Activation Energies for Carrier Capture by Defects in Semiconductors

    Modine, N. A.; Wright, A. F.; Lee, S. R.

    The rate of defect-induced carrier recombination is determined by both defect levels and carrier capture cross-sections. Density functional theory (DFT) has been widely and successfully used to predict defect levels, but only recently has work begun to focus on using DFT to determine carrier capture cross-sections. Lang and Henry developed the theory of carrier-capture by multiphonon emission in the 1970s and showed that carrier-capture cross-sections differ between defects primarily due to differences in their carrier capture activation energies. We present an approach to using DFT to calculate carrier capture activation energies that does not depend on an assumed configuration coordinate and that fully accounts for anharmonic effects, which can substantially modify carrier activation energies. We demonstrate our approach for intrinisic defects in GaAs and GaN and discuss how our results depend on the choice of exchange-correlation functional and the treatment of spin polarization. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under Contract DE-AC04-94AL85000.

  20. Pyrophosphate as a central energy carrier in the hydrogen-producing extremely thermophilic Caldicellulosiruptor saccharolyticus

    Bielen, A.A.M.; Willquist, K.; Engman, J.; Oost, van der J.; Niel, van E.W.J.; Kengen, S.W.M.

    2010-01-01

    The role of inorganic pyrophosphate (PPi) as an energy carrier in the central metabolism of the extremely thermophilic bacterium Caldicellulosiruptor saccharolyticus was investigated. In agreement with its annotated genome sequence, cell extracts were shown to exhibit PPi-dependent

  1. ENERGY EFFICIENCY, ENERGY SAVING POTENTIAL AND ENVIRONMENTAL IMPACT RESEARCH OF LPG CARRIER REFRIGERATION SYSTEM

    V. О. Bedrosov

    2016-12-01

    Full Text Available Nowadays energy efficiency improvement and global warming are issues of current interest because of the natural resources depletion and extreme climate change. Thus, the problem of formation of strict regulations regarding emissions into the air arises. This paper presents the study of cascade refrigeration system for re-condensing of associated petroleum gas during sea transportation for LPG carrier. The structural optimization has been performed. LPG gas carriers with 266 000 m3 ethane capacity require 15 MW cascade refrigeration system for re-condensing if the temperature in the coastal LPG storage is -70°C, and the temperature for transported Ethan is maintained at  -75°C. For current storage conditions the required system cooling capacity is only 1,078 MW intended for the heat gain rejection from the environment during Ethane transportation. The replacement of ozone-depleting refrigerant R22 to alternative agents: R407C, R404A, R402A, R717, R290, R1270 was estimated. The results of analysis have shown that the proposed improvements can be used to optimize the LPG carrier cascade refrigeration system

  2. Optimal Scheduling of a Multi-Carrier Energy Hub Supplemented By Battery Energy Storage Systems

    Javadi, Mohammad Sadegh; Anvari-Moghaddam, Amjad; Guerrero, Josep M.

    2017-01-01

    This paper introduces a management model for optimal scheduling of a multi-carrier energy hub. In the proposed hub, three types of assets are considered: dispersed generating systems (DGs) such as micro-combined heat and power (mCHP) units, storage devices such as battery-based electrical storage...... systems (ESSs), and heating/cooling devices such as electrical heater, heat-pumps and absorption chillers. The optimal scheduling and management of the examined energy hub assets in line with electrical transactions with distribution network is modeled as a mixed-integer non-linear optimization problem....... In this regard, optimal operating points of DG units as well as ESSs are calculated based on a cost-effective strategy. Degradation cost of ESSs is also taken into consideration for short-term scheduling. Simulation results demonstrate that including well-planned energy storage options together with optimal...

  3. Impact of energy filtering and carrier localization on the thermoelectric properties of granular semiconductors

    Narducci, Dario, E-mail: dario.narducci@unimib.it [Department of Materials Science, University of Milano Bicocca, via Cozzi 53, 20125 Milano (Italy); Consorzio DeltaTi Research (Italy); Selezneva, Ekaterina [Department of Materials Science, University of Milano Bicocca, via Cozzi 53, 20125 Milano (Italy); Cerofolini, Gianfranco [Department of Materials Science, University of Milano Bicocca, via Cozzi 53, 20125 Milano (Italy); Consorzio DeltaTi Research (Italy); Frabboni, Stefano; Ottaviani, Giampiero [Department of Physics, University of Modena and Reggio Emilia, via Campi 213, 41100 Modena (Italy)

    2012-09-15

    Energy filtering has been widely considered as a suitable tool to increase the thermoelectric performances of several classes of materials. In its essence, energy filtering provides a way to increase the Seebeck coefficient by introducing a strongly energy-dependent scattering mechanism. Under certain conditions, however, potential barriers may lead to carrier localization, that may also affect the thermoelectric properties of a material. A model is proposed, actually showing that randomly distributed potential barriers (as those found, e.g., in polycrystalline films) may lead to the simultaneous occurrence of energy filtering and carrier localization. Localization is shown to cause a decrease of the actual carrier density that, along with the quantum tunneling of carriers, may result in an unexpected increase of the power factor with the doping level. The model is corroborated toward experimental data gathered by several authors on degenerate polycrystalline silicon and lead telluride. - Graphical abstract: In heavily doped semiconductors potential barriers may lead to both carrier energy filtering and localization. This may lead to an enhancement of the thermoelectric properties of the material, resulting in an unexpected increase of the power factor with the doping level. Highlights: Black-Right-Pointing-Pointer Potential barriers are shown to lead to carrier localization in thermoelectric materials. Black-Right-Pointing-Pointer Evidence is put forward of the formation of a mobility edge. Black-Right-Pointing-Pointer Energy filtering and localization may explain the enhancement of power factor in degenerate semiconductors.

  4. Achieving Uniform Carriers Distribution in MBE Grown Compositionally Graded InGaN Multiple-Quantum-Well LEDs

    Mishra, Pawan; Janjua, Bilal; Ng, Tien Khee; Shen, Chao; Salhi, Abdelmajid; Alyamani, Ahmed; El-Desouki, Munir; Ooi, Boon S.

    2015-01-01

    We investigated the design and growth of compositionally-graded InGaN multiple quantum wells (MQW) based light-emitting diode (LED) without an electron-blocking layer (EBL). Numerical investigation showed uniform carrier distribution in the active region, and higher radiative recombination rate for the optimized graded-MQW design, i.e. In0→xGa1→(1-x)N / InxGa(1-x)N / Inx→0Ga(1-x)→1N, as compared to the conventional stepped-MQW-LED. The composition-grading schemes, such as linear, parabolic, and Fermi-function profiles were numerically investigated for comparison. The stepped- and graded-MQW-LED were then grown using plasma assisted molecular beam epitaxy (PAMBE) through surface-stoichiometry optimization based on reflection high-energy electron-diffraction (RHEED) in-situ observations. Stepped- and graded-MQW-LED showed efficiency roll over at 160 A/cm2 and 275 A/cm2, respectively. The extended threshold current density roll-over (droop) in graded-MQW-LED is due to the improvement in carrier uniformity and radiative recombination rate, consistent with the numerical simulation.

  5. Achieving Uniform Carriers Distribution in MBE Grown Compositionally Graded InGaN Multiple-Quantum-Well LEDs

    Mishra, Pawan

    2015-05-06

    We investigated the design and growth of compositionally-graded InGaN multiple quantum wells (MQW) based light-emitting diode (LED) without an electron-blocking layer (EBL). Numerical investigation showed uniform carrier distribution in the active region, and higher radiative recombination rate for the optimized graded-MQW design, i.e. In0→xGa1→(1-x)N / InxGa(1-x)N / Inx→0Ga(1-x)→1N, as compared to the conventional stepped-MQW-LED. The composition-grading schemes, such as linear, parabolic, and Fermi-function profiles were numerically investigated for comparison. The stepped- and graded-MQW-LED were then grown using plasma assisted molecular beam epitaxy (PAMBE) through surface-stoichiometry optimization based on reflection high-energy electron-diffraction (RHEED) in-situ observations. Stepped- and graded-MQW-LED showed efficiency roll over at 160 A/cm2 and 275 A/cm2, respectively. The extended threshold current density roll-over (droop) in graded-MQW-LED is due to the improvement in carrier uniformity and radiative recombination rate, consistent with the numerical simulation.

  6. Optimal Scheduling of Biogas-Solar-Wind Renewable Portfolio for Multi-Carrier Energy Supplies

    Zhou, Bin; Xu, Da; Li, Canbing

    2018-01-01

    the mitigation of renewable intermittency and the efficient utilization of batteries, and a multi-carrier generation scheduling scheme is further presented to dynamically optimize dispatch factors in the coupling matrix for energy-efficient con-version and storage, while different energy demands of end......This paper proposes a multi-source multi-product framework for coupled multi-carrier energy supplies with a biogas-solar-wind hybrid renewable system. In this framework, the biogas-solar-wind complementarities are fully exploited based on digesting thermodynamic effects for the synergetic...... interactions of electricity, gas and heating energy flows, and a coupling matrix is formulated for the modeling of production, conversion, storage, and consumption of different energy carriers. The multi-energy complementarity of biogas-solar-wind renewable portfolio can be utilized to facilitate...

  7. Sources and carriers of energy in the 21st century

    Hafele, W.

    1976-01-01

    This Dutch summary of a paper read in English has diagrams in English. Topics discussed include the basic materials - coal, lignite, oil and natural gas; world energy requirements; the saving of energy; long term energy supply; system problems; and the application of nuclear fission and the solar energy. Energy strategies being developed at the International Institute for Applied Systems Analysis at Laxenburg in Austria are described. (D.J.B.)

  8. Reducing consumption of electric current and energy carriers. [USSR

    Ruppo, A.S.; Gruzdev, Yu.M.

    1985-01-01

    Evaluates the energy conservation program developed by the Giproshakht research institute is evaluated. The program was used in the Afanas'evo hydraulic mine in the Tulaugol association (with annual coal output of 2.1 Mt). Energy conservation program consisted of 2 groups of tasks: reducing energy consumption of the mine, and reducing energy consumption during the maximum demand hours in the morning and evening. The following methods were used: reducing idle running of chain and belt conveyors, separate draining of mine water free of dust and rock particles (reducing range of water cleaning), use of automatic control systems for mine blowers, automatic control of the system for coal drying, more efficient use of coal and materials transport in the mine. Energy demand of the mine during peak demand hours was reduced by adjusting fluctuations of energy consumption of the mine to fluctuations of energy demand in the power system of the area, e.g. by reducing mine draining in the morning and evening and operating at full capacity during the time of reduced energy demand. Using the energy conservation measures economized 4,324,300 kWh electric energy annually.

  9. Some aspects of hydrogen as a long-term energy carrier

    Quakernaat, J.; De Jong, K.P.; Van Wechem, H.M.H.; Okken, P.A.; Lako, P.; Ybema, J.R.

    1994-11-01

    Hydrogen as a secondary energy carrier received extensive and worldwide attention some ten to fifteen years ago. The developments in the energy market since then have reduced the interest in hydrogen. However, the increased concern for the environment and new technical options have brought hydrogen to the centre of attention once again. These considerations led to the organization of the National Hydrogen Seminar, held on 19 November 1993 at ECN, Petten, Netherlands. Eight experts in the field of hydrogen illustrated the possibilities and prospects of the production, storage and use of hydrogen as an energy carrier. In this report three of these contributions are presented, for which separate abstracts have been prepared. The first paper is on hydrogen in a global long-term perspective, in the second paper carbon is considered as a hydrogen carrier or as a disappearing skeleton, and in the third paper attention is paid to the cost effective integration of hydrogen in energy systems with CO 2 constraints

  10. Anaerobic biotechnological approaches for production of liquid energy carriers from biomass

    Karakashev, Dimitar Borisov; Thomsen, Anne Belinda; Angelidaki, Irini

    2007-01-01

    In recent years, increasing attention has been paid to the use of renewable biomass for energy production. Anaerobic biotechnological approaches for production of liquid energy carriers (ethanol and a mixture of acetone, butanol and ethanol) from biomass can be employed to decrease environmental...... pollution and reduce dependency on fossil fuels. There are two major biological processes that can convert biomass to liquid energy carriers via anaerobic biological breakdown of organic matter: ethanol fermentation and mixed acetone, butanol, ethanol (ABE) fermentation. The specific product formation...

  11. Charged-particle multiplicity at LHC energies

    CERN. Geneva

    2010-01-01

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

  12. A comparative study of ammonia energy systems as a future energy carrier, with particular reference to vehicle use in Japan

    Miura, Daisuke; Tezuka, Tetsuo

    2014-01-01

    The choice of secondary energy carriers, such as electricity, hydrogen and ammonia, influences not only economic and environmental performances but also the reliability of an entire energy system. This article focuses on ammonia because of its excellent property in energy storage, and assesses the relative advantages of several ammonia energy systems for vehicle use in Japan by estimating energy efficiency, CO 2 emissions, and the supply cost of several ammonia energy paths, which are then compared with alternative paths using different energy carriers including hydrogen and electricity. The article also discusses inherent merits and challenges of ammonia energy systems and identifies directions for future research and development. Using ammonia as an energy carrier was demonstrated to be competitive in terms of efficiency, CO 2 emissions and supply cost for energy systems requiring fairly large numbers of storage days. This assessment shows that the use of ammonia in an energy system can improve the continuity of the energy supply in a country or region with insecurity of supply. On the other hand, we argue that further technical improvements and cost reduction associated with both conventional and unconventional ammonia production is imperative for using ammonia in a normal energy system. - Highlights: • We assess merits of energy supply systems using ammonia as an energy carrier. • Comparison with hydrogen or electricity-based energy systems was carried out. • We find ammonia is competitive when requiring large numbers of storage days. • The use of ammonia in energy systems can improve the continuity of energy supply. • Technical improvements are needed to make ammonia attractive in normal systems

  13. Redox Homeostasis in Plants under Abiotic Stress: Role of electron carriers, energy metabolism mediators and proteinaceous thiols

    Dhriti Kapoor

    2015-03-01

    Full Text Available Contemporaneous presence of both oxidized and reduced forms of electron carriers is mandatory in efficient flux by plant electron transport cascades. This requirement is considered as redox poising that involves the movement of electron from multiple sites in respiratory and photosynthetic electron transport chains to molecular oxygen. This flux triggers the formation of superoxide, consequently give rise to other reactive oxygen species (ROS under adverse environmental conditions like drought, high or low temperature, heavy metal stress etc. that plants owing during their life span. Plant cells synthesize ascorbate, an additional hydrophilic redox buffer, which protect the plants against oxidative challenge. Large pools of antioxidants also preside over the redox homeostasis. Besides, tocopherol is a liposoluble redox buffer, which efficiently scavenges the ROS like singlet oxygen. In addition, proteinaceous thiol members such as thioredoxin, peroxiredoxin and glutaredoxin, electron carriers and energy metabolism mediators phosphorylated (NADP and non-phosphorylated (NAD+ coenzyme forms interact with ROS, metabolize and maintain redox homeostasis.

  14. Multiplicities and minijets at Tevatron Collider energies

    Sarcevic, I.

    1989-01-01

    We show that in the parton branching model, the probability distribution does not obey KNO scaling. As energy increases, gluon contribution to multiplicities increases, resulting in the widening of the probability distribution, in agreement with experimental data. We predict that the widening of the distribution will stop at Tevatron Collider energies due to the dominant role of gluons at these energies. We also find that the gluon contribution to the 'minijet' cross section increases with energy and becomes dominant at the Tevatron Collider. We calculate QCD minijet cross sections for a variety of structure functions, QCD scales and p T min . We compare our theoretical results with the experimental data and find that some of the structure functions and choices of scale are preferred by the experimental data. We give theoretical predictions for the minijet cross section at the Tevatron Collider, indicating the possibility of distinguishing between different sets of structure functions and choices of scale. (orig.)

  15. Hermitian symmetry free optical-single-carrier frequency division multiple access for visible light communication

    Azim, Ali W.; Le Guennec, Yannis; Maury, Ghislaine

    2018-05-01

    Optical-orthogonal frequency division multiplexing (O-OFDM) is an effective scheme for visible light communications (VLC), offering a candid extension to multiple access (MA) scenarios, i.e., O-OFDMA. However, O-OFDMA exhibits high peak-to-average power ratio (PAPR), which exacerbates the non-linear distortions from the light emitting diode (LED). To overcome high PAPR while sustaining MA, optical-single-carrier frequency-division multiple access (O-SCFDMA) is used. For both O-OFDMA and O-SCFDMA, Hermitian symmetry (HS) constraint is imposed in frequency-domain (FD) to obtain a real-valued time-domain (TD) signal for intensity modulation-direct detection (IM-DD) implementation of VLC. Howbeit, HS results in an increase of PAPR for O-SCFDMA. In this regard, we propose HS free (HSF) O-SCFDMA (HSFO-SCFDMA). We compare HSFO-SCFDMA with several approaches in key parameters, such as, bit error rate (BER), optical power penalty, PAPR, quantization, electrical power efficiency and system complexity. BER performance and optical power penalty is evaluated considering multipath VLC channel and taking into account the bandwidth limitation of LED in combination with its optimized driver. It is illustrated that HSFO-SCFDMA outperforms other alternatives.

  16. On the Multiplicity Distributions at LHC Energies

    Fialkowski, K.; Wit, R.

    2011-01-01

    The ALICE and CMS data on the multiplicity distributions are compared with the lower energy data and with the results from the 8.142 version of the PYTHIA MC event generator with two tunings. The ALICE data for moments are used to calculate the factorial cumulants. It is suggested that the data on moments or cumulants are well suited to specify the optimal tuning of the model parameters. (authors)

  17. Distribution of energy carriers and resulting CO2 emission caused by the use of energy in Norwegian buildings

    Enlid, Elin; Tokle, Trude

    1999-03-01

    This report calculates the primary energy used in heating and management of buildings in Norway and distributes it according to user category and energy carrier. It also calculates the emission of carbon dioxide caused by this energy use. The total amount of energy used for heating and management of buildings in Norway in 1997 was 84 TWh. The corresponding emission of carbon dioxide was 10.5 mill tonnes, about 25% of the total domestic emission of carbon dioxide, including transport

  18. Hydrogen and Biofuels - A Modeling Analysis of Competing Energy Carriers for Western Europe

    Guel, Timur; Kypreos, Socrates; Barreto, Leonardo

    2007-07-01

    This paper deals with the prospects of hydrogen and biofuels as energy carriers in the Western European transportation sector. The assessment is done by combining the US hydrogen analysis H2A models for the design of hydrogen production and delivery chains, and the Western European Hydrogen Markal Model EHM with a detailed representation of biofuels, and the European electricity and transportation sector. The paper derives policy recommendations to support the market penetration of hydrogen and biofuels, and investigates learning interactions between the different energy carriers. (auth)

  19. Methodology for the assessment of oxygen as an energy carrier

    Yang, Ming Wei

    Due to the energy intensity of the oxygen generating process, the electric power grid would benefit if the oxygen generating process was consumed electric power only during low demand periods. Thus, the question to be addressed in this study is whether oxygen production and/or usage can be modified to achieve energy storage and/or transmission objectives at lower cost. The specific benefit to grid would be a leveling, over time, of the demand profile and thus would require less installation capacity. In order to track the availability of electricity, a compressed air storage unit is installed between the cryogenic distillation section and the main air compressor of air separation unit. A profit maximizing scheme for sizing storage inventory and related equipments is developed. The optimum scheme is capable of market responsiveness. Profits of steel maker, oxy-combustion, and IGCC plants with storage facilities can be higher than those plants without storage facilities, especially, at high-price market. Price tracking feature of air storage integration will certainly increase profit margins of the plants. The integration may push oxy-combustion and integrated gasification combined cycle process into economic viability. Since oxygen is used in consumer sites, it may generate at remote locations and transport to the place needed. Energy losses and costs analysis of oxygen transportation is conducted for various applications. Energy consumptions of large capacity and long distance GOX and LOX pipelines are lower than small capacity pipelines. However, transportation losses and costs of GOX and LOX pipelines are still higher than electricity transmission.

  20. Biomass-based energy carriers in the transportation sector; Biomassebaserade energibaerare foer transportsektorn

    Johansson, Bengt

    1995-03-01

    The purpose of this report is to study the technical and economic prerequisites to attain reduced carbon dioxide emissions through the use of biomass-based energy carriers in the transportation sector, and to study other environmental impacts resulting from an increased use of biomass-based energy carriers. CO{sub 2} emission reduction per unit arable and forest land used for biomass production (kg CO{sub 2}/ha,year) and costs for CO{sub 2} emission reduction (SEK/kg CO{sub 2}) are estimated for the substitution of gasoline and diesel with rape methyl ester, biogas from lucerne, ethanol from wheat and ethanol, methanol, hydrogen and electricity from Salix and logging residues. Of the studied energy carriers, those based on Salix provide the largest CO{sub 2} emission reduction. In a medium long perspective, the costs for CO{sub 2} emission reduction seem to be lowest for methanol from Salix and logging residues. The use of fuel cell vehicles, using methanol or hydrogen as energy carriers, can in a longer perspective provide more energy efficient utilization of biomass for transportation than the use of internal combustion engine vehicles. 136 refs, 12 figs, 25 tabs

  1. Sodium tetra-hydro-borate as energy/hydrogen carrier, its history

    Demirci, U.B.; Miele, Ph.

    2009-01-01

    Sodium tetra-hydro-borate NaBH 4 is considered as being a promising energy/hydrogen carrier. NaBH 4 is not a new compound. It has been discovered in 1940's by Prof. H.C. Brown, Nobel Laureate in Chemistry in 1979. NaBH 4 has thus a history and this history distinguishes the NaBH 4 utilisation as hydrogen carrier from that as energy carrier. In fact, the history of NaBH 4 (for both utilizations) can be divided into three periods, each period being characterised by specific societal challenges. Whereas during the first period the challenges were military and political, the challenges in the third period (i.e. at present) are energetic, environmental, civilian, social and political. The second period was rather calm for NaBH 4 even if it was intensively used as a reducing agent in organic chemistry. (authors)

  2. A simple carrier frequency offset synchronization strategy for multiple relay cooperative diversity ofdm system

    Mudassar, I.; Cheema, A.; Shoab, A.

    2014-01-01

    Cooperative Diversity Orthogonal Frequency Division Modulation (CD-OFDM) systems are very sensitive to synchronization errors. In CD-OFDM, synchronization is more complex because all cooperative nodes (CNs) have their own frequency oscillator and different channel path which results in different timing and carrier frequency offset (CFO) for each node. Consequently, each node has to be synchronized separately without affecting the synchronization process of other nodes. All CNs transmit simultaneously during cooperation phase (C-phase) and their aggregate signal is received at the destination node. A unique frequency domain (FD) preamble is proposed for each CN during C-phase that will allow simple separation of cooperative nodes. These FD multiplexed preambles make the synchronization problem identical to OFDMA uplink. OFDMA system typically uses highly complex iterative CFO estimators for uplink synchronization. However, a simple one-shot CFO estimator is proposed that uses repeated preamble of two OFDM symbol duration. The proposed method is computationally efficient because it relies on FFT operation for user separation and interference mitigation. Subsequently, time domain (TD) multiplication is used for CFO correction of each CN. Furthermore, a CD-OFDM protocol for data transmission is presented that suites the proposed estimator and harnesses spatial diversity. The proposed estimator shows good statistical results during simulations in AWGN and Rayleigh environments. During evaluation, estimator variance, mean square error and symbol error rate are used as performance measure. (author)

  3. Methane and methanol as energy carriers. Economy study

    Deipenau, H

    1977-12-01

    The objective of the study was to develop economic and technical means of supplying LNG and methanol to the industrial centers of Germany using natural gas from the Iranian area as the raw material. The available possibilities for the preparation, transport, and storage of LNG and methanol were clarified and examined. Cost estimates were made of transport from Kangan to Wilhelmshaven. Alternatives were compared from economic and technical viewpoints. Ways in which LNG and methanol could be used in Germany (motor cars, power plants, gas utilities) were evaluated. The evaluations showed that energy costs for LNG in Wilhelmshaven are lower than those for methanol. Large quantities of LNG and methanol from the Persian Gulf can be sold in the various branches of the German energy market on the condition that the crude gas price of the Iranian Gulf does not exceed 1.- to 3.-DM/Gcal. At present the natural gas exporting countries demand crude natural gas prices of about 5.-DM/Gcal.

  4. Simulation Performance of Multiple-Input Multiple-Output Systems Employing Single-Carrier Modulation and Orthogonal Frequency Division Multiplexing

    Saglam, Halil D

    2004-01-01

    ...) systems utilizing Alamouti-based space-time block coding (STBC) technique. The MIMO communication systems using STBC technique employing both single-carrier modulation and orthogonal frequency division multiplexing (OFDM...

  5. Towards Terabit Carrier Ethernet and Energy Efficient Optical Transport Networks

    Rasmussen, Anders

    This thesis focuses on the challenges of scaling current network node technology to support connection speeds of 100Gbps and beyond. Out of the many exiting aspects of reaching this goal, the main scope of this thesis is to investigate packet processing (address lookup and scheduling), forward....... The more advanced schemes also require more complex calculations to process each bit. This thesis will investigate how both the standard OTN FEC as well as more advanced FEC schemes can be implemented for 100G and above operation. As the networks are expanded to run at increasingly higher speeds...... error correction and energy efficiency. Scheduling and address lookup are key functions and potential bottle necks in high speed network nodes, as the minimum packet/frame sizes in both the popular Ethernet protocol, as well as the Internet Protocol (IP) still remains constant (84B and 40B, respectively...

  6. Efficiency analysis for the production of modern energy carriers from renewable resources and wastes

    Ptasinski, K.J.; Tiezzi, E.; Marques, J.C.; Brebbia, C.A.; Jorgensen, S.E.

    2007-01-01

    Two global problems related to the use of fossil fuels are fast depletion and environmental damage. Biomass has a great potential as a clean renewable feedstock for producing modern energy carriers such as biodiesel, methanol, and hydrogen. However, the use of biomass is accompanied by possible

  7. LTE UE Energy Saving by Applying Carrier Aggregation in a HetNet Scenario

    Lauridsen, Mads; Wang, Hua; Mogensen, Preben

    2013-01-01

    In this work it is examined if downlink Carrier Aggregation (CA) can be used to save UE energy. A dual-receiver LTE release 10 UE is compared with a single-receiver LTE release 8 UE. The models are based on scaling of an existing LTE release 8 UE power model. The energy consumption of the UEs...... is examined in a Heterogeneous Network scenario consisting of macro and small cells. The unexpected conclusion is that CA UEs can save energy, compared to LTE release 8 UEs, if they, depending on cell load, experience a throughput gain of 20%. However if the UE throughput is unaltered the energy consumption...

  8. Direct Effect of Dielectric Surface Energy on Carrier Transport in Organic Field-Effect Transistors.

    Zhou, Shujun; Tang, Qingxin; Tian, Hongkun; Zhao, Xiaoli; Tong, Yanhong; Barlow, Stephen; Marder, Seth R; Liu, Yichun

    2018-05-09

    The understanding of the characteristics of gate dielectric that leads to optimized carrier transport remains controversial, and the conventional studies applied organic semiconductor thin films, which introduces the effect of dielectric on the growth of the deposited semiconductor thin films and hence only can explore the indirect effects. Here, we introduce pregrown organic single crystals to eliminate the indirect effect (semiconductor growth) in the conventional studies and to undertake an investigation of the direct effect of dielectric on carrier transport. It is shown that the matching of the polar and dispersive components of surface energy between semiconductor and dielectric is favorable for higher mobility. This new empirical finding may show the direct relationship between dielectric and carrier transport for the optimized mobility of organic field-effect transistors and hence show a promising potential for the development of next-generation high-performance organic electronic devices.

  9. Solitons as candidates for energy carriers in Fermi-Pasta-Ulam lattices

    Ming, Yi; Ye, Liu; Chen, Han-Shuang; Mao, Shi-Feng; Li, Hui-Min; Ding, Ze-Jun

    2018-01-01

    Currently, effective phonons (renormalized or interacting phonons) rather than solitary waves (for short, solitons) are regarded as the energy carriers in nonlinear lattices. In this work, by using the approximate soliton solutions of the corresponding equations of motion and adopting the Boltzmann distribution for these solitons, the average velocities of solitons are obtained and are compared with the sound velocities of energy transfer. Excellent agreements with the numerical results and the predictions of other existing theories are shown in both the symmetric Fermi-Pasta-Ulam-β lattices and the asymmetric Fermi-Pasta-Ulam-α β lattices. These clearly indicate that solitons are suitable candidates for energy carriers in Fermi-Pasta-Ulam lattices. In addition, the root-mean-square velocity of solitons can be obtained from the effective phonons theory.

  10. Hydrogen as an energy carrier and its production by nuclear power

    NONE

    1999-05-01

    The impact of power generation on environment is becoming an ever increasing concern in decision making when considering the energy options and power systems required by a country in order to sustain its economic growth and development. Hydrogen is a strong emerging candidate with a significant role as a clean, environmentally benign and safe to handle major energy carrier in the future. Its enhanced utilization in distributed power generation as well as in propulsion systems for mobile applications will help to significantly mitigate the strong negative effects on the environment. It ia also the nuclear power that will be of utmost importance in the energy supply of many countries over the next decades. The development of new, innovative reactor concepts utilizing passive safety features for process heat and electricity generation are considered by many to play a substantial role in the world`s energy future in helping to reduce greenhouse gas emissions. This report produced by IAEA documents past and current activities in Member States in the development of hydrogen production as an energy carrier and its corresponding production through the use of nuclear power. It provides an introduction to nuclear technology as a means of producing hydrogen or other upgraded fuels and to the energy carries hydrogen and its main fields of application. Emphasis is placed on high-temperature reactor technology which can achieve the simultaneous generation of electricity and the production of high-temperature process heat Refs, figs, tabs

  11. Hydrogen as an energy carrier and its production by nuclear power

    1999-05-01

    The impact of power generation on environment is becoming an ever increasing concern in decision making when considering the energy options and power systems required by a country in order to sustain its economic growth and development. Hydrogen is a strong emerging candidate with a significant role as a clean, environmentally benign and safe to handle major energy carrier in the future. Its enhanced utilization in distributed power generation as well as in propulsion systems for mobile applications will help to significantly mitigate the strong negative effects on the environment. It ia also the nuclear power that will be of utmost importance in the energy supply of many countries over the next decades. The development of new, innovative reactor concepts utilizing passive safety features for process heat and electricity generation are considered by many to play a substantial role in the world's energy future in helping to reduce greenhouse gas emissions. This report produced by IAEA documents past and current activities in Member States in the development of hydrogen production as an energy carrier and its corresponding production through the use of nuclear power. It provides an introduction to nuclear technology as a means of producing hydrogen or other upgraded fuels and to the energy carries hydrogen and its main fields of application. Emphasis is placed on high-temperature reactor technology which can achieve the simultaneous generation of electricity and the production of high-temperature process heat

  12. Assessment of the potential future market in Sweden for hydrogen as an energy carrier

    Carleson, G.

    Future hydrogen markets for the period 1980-2025 are projected, the probable range of hydrogen production costs for various manufacturing methods is estimated, and expected market shares in competition with alternative energy carriers are evaluated. A general scenario for economic and industrial development in Sweden for the given period was evaluated, showing the average increase in gross national product to become 1.6% per year. Three different energy scenarios were then developed: alternatives were based on nuclear energy, renewable indigenous energy sources, and the present energy situation with free access to imported natural or synthetic fuels. An analysis was made within each scenario of the competitiveness of hydrogen on both the demand and the supply of the following sectors: chemical industry, steel industry, peak power production, residential and commercial heating, and transportation. Costs were calculated for the production, storage and transmission of hydrogen according to technically feasible methods and were compared to those of alternative energy carriers. Health, environmental and societal implications were also considered. The market penetration of hydrogen in each sector was estimated, and the required investment capital was shown to be less than 4% of the national gross investment sum.

  13. Generation of multiple excitons in Ag2S quantum dots: Single high-energy versus multiple-photon excitation

    Sun, Jingya

    2014-02-20

    We explored biexciton generation via carrier multiplication (or multiple-exciton generation) by high-energy photons and by multiple-photon absorption in Ag2S quantum dots (QDs) using femtosecond broad-band transient absorption spectroscopy. Irrespective of the size of the QDs and how the multiple excitons are generated in the Ag2S QDs, two distinct characteristic time constants of 9.6-10.2 and 135-175 ps are obtained for the nonradiative Auger recombination of the multiple excitons, indicating the existence of two binding excitons, namely, tightly bound and weakly bound excitons. More importantly, the lifetimes of multiple excitons in Ag 2S QDs were about 1 and 2 orders of magnitude longer than those of comparable size PbS QDs and single-walled carbon nanotubes, respectively. This result is significant because it suggests that by utilizing an appropriate electron acceptor, there is a higher possibility to extract multiple electron-hole pairs in Ag2S QDs, which should improve the performance of QD-based solar cell devices. © 2014 American Chemical Society.

  14. Generation of multiple excitons in Ag2S quantum dots: Single high-energy versus multiple-photon excitation

    Sun, Jingya; Yu, Weili; Usman, Anwar; Isimjan, Tayirjan T.; Del Gobbo, Silvano; Alarousu, Erkki; Takanabe, Kazuhiro; Mohammed, Omar F.

    2014-01-01

    We explored biexciton generation via carrier multiplication (or multiple-exciton generation) by high-energy photons and by multiple-photon absorption in Ag2S quantum dots (QDs) using femtosecond broad-band transient absorption spectroscopy. Irrespective of the size of the QDs and how the multiple excitons are generated in the Ag2S QDs, two distinct characteristic time constants of 9.6-10.2 and 135-175 ps are obtained for the nonradiative Auger recombination of the multiple excitons, indicating the existence of two binding excitons, namely, tightly bound and weakly bound excitons. More importantly, the lifetimes of multiple excitons in Ag 2S QDs were about 1 and 2 orders of magnitude longer than those of comparable size PbS QDs and single-walled carbon nanotubes, respectively. This result is significant because it suggests that by utilizing an appropriate electron acceptor, there is a higher possibility to extract multiple electron-hole pairs in Ag2S QDs, which should improve the performance of QD-based solar cell devices. © 2014 American Chemical Society.

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

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

    2015-01-01

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

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

    Takeda, Yasuhiko, E-mail: takeda@mosk.tytlabs.co.jp; Sugimoto, Noriaki [Toyota Central Research and Development Laboratories, Inc., 41-1, Yokomichi, Nagakute, Aichi 480-1192 (Japan); Ichiki, Akihisa [Green Mobility Collaborative Research Center, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601 (Japan); Kusano, Yuya [Green Mobility Collaborative Research Center, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601 (Japan); Toyota Motor Corp., 1200 Mishuku, Susono, Shizuoka 410-1193 (Japan); Motohiro, Tomoyoshi [Toyota Central Research and Development Laboratories, Inc., 41-1, Yokomichi, Nagakute, Aichi 480-1192 (Japan); Green Mobility Collaborative Research Center, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601 (Japan); Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8601 (Japan)

    2015-09-28

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

  17. Mean charged hadron multiplicities in high-energy collisions

    Albini, E [Istituto di Matematica dell' Universita Cattolica di Brescia (Italy); Capiluppi, P; Giacomelli, G; Rossi, A M [Bologna Univ. (Italy). Istituto di Fisica

    1976-03-01

    A collection of mean charged hadron multiplicities per inelastic collision in various high-energy processes is presented. An extensive list of fits of as a function of energy is presented and discussed. As the energy increases the multiplicities for different collisions tend to a unique curve, independent of the type of colliding particles.

  18. 46 CFR 111.10-5 - Multiple energy sources.

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Multiple energy sources. 111.10-5 Section 111.10-5...-GENERAL REQUIREMENTS Power Supply § 111.10-5 Multiple energy sources. Failure of any single generating set energy source such as a boiler, diesel, gas turbine, or steam turbine must not cause all generating sets...

  19. Current and future competitiveness of renewable energy carriers - Conceptions about competitiveness

    Lundgren, K.

    1998-01-01

    The dissertation draws attention to the fact that in the world today 80% of the resources that are used are limited - non renewable energy carriers - and because of the long time between planning and doing (carrying out) within the energy sector, it is worthwhile from the long-term perspective to steer early on towards more sustainable solutions, such as renewable energy carriers. The State and the market have begun to adjust to concepts such as 'competitiveness', which can be viewed as containing both feasibility and legitimacy aspects - the state through different regulations and environmental taxes and environmental fees, and actors on the market that marginally produce/choose renewable energy carriers. The overlying methodology in the dissertation is an actor's viewpoint. This viewpoint brings forth, in turn, two different views, the analytical and the interpretative. The dissertation presents different stances within the energy sector: commercial production logic, commercial sustainability logic, and the socio-economic sustainability logic. By drawing one's attention to how one has the possibility to create (enact) his own reality, it is possible to highlight how organisations can increase their competitiveness by being conscious of their own view and others, logic, which in turn forms their views about competitiveness, which in turn determines which projects will materialize. Enterprises and individuals create a description of reality together through a dialectic process, i.e. by developing an environmental management system that contains elements of environmental auditing, environmental performance indicators, and environmental labelling, which 'reveal' the production conditions that lie behind the actualization of the final product. An example is the product, 'green' electricity, which, in spite of the fact that the final product - electricity - is identical irrespective of the production method, just at the moment can be sold at different prices according

  20. Assessing the Multiple Benefits of Clean Energy Chapter 1: Introduction

    Chapter 1 of “Assessing the Multiple Benefits of Clean Energy” provides an introduction to the document. /meta name=DC.title content=Assessing the Multiple Benefits of Clean Energy Chapter 1: Introduction

  1. Spin and energy transfer between magnetic ions and free carriers in diluted-magnetic semiconductor heterostructures

    Yakovlev, D.R. [Experimental Physics 2, University of Dortmund, 44227 Dortmund (Germany); Ioffe Physico-Technical Institute, Russian Academy of Sciences, 194021 St. Petersburg (Russian Federation); Kneip, M.; Bayer, M. [Experimental Physics 2, University of Dortmund, 44227 Dortmund (Germany); Maksimov, A.A.; Tartakovskii, I.I. [Institute of Solid State Physics, Russian Academy of Sciences, 142432 Chernogolovka (Russian Federation); Keller, D.; Ossau, W.; Molenkamp, L.W. [Physikalisches Institut der Universitaet Wuerzburg, 97074 Wuerzburg (Germany); Scherbakov, A.V.; Akimov, A.V. [Ioffe Physico-Technical Institute, Russian Academy of Sciences, 194021 St. Petersburg (Russian Federation); Waag, A. [Abteilung Halbleiterphysik, Universitaet Ulm, 89081 Ulm (Germany)

    2004-03-01

    In this paper we give a brief overview of our studies on dynamical processes in diluted-magnetic-semiconductor heterostructures based on (Zn,Mn)Se and (Cd,Mn)Te. Presence of free carriers is an important factor which determines the energy- and spin transfer in a coupled systems of magnetic ions, lattice (the phonon system) and carriers. We report also new data on dynamical response of magnetic ions interacting with photogenerated electron-hole plasma. (Zn,Mn)Se/(Zn,Be)Se structures with relatively high Mn content of 11% provide spin-lattice relaxation time of about 20 ns, which is considerably shorter then the characteristic times of nonequilibrium phonons ranging to 1 {mu}s. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  2. Efficient charge-carrier extraction from Ag₂S quantum dots prepared by the SILAR method for utilization of multiple exciton generation.

    Zhang, Xiaoliang; Liu, Jianhua; Johansson, Erik M J

    2015-01-28

    The utilization of electron-hole pairs (EHPs) generated from multiple excitons in quantum dots (QDs) is of great interest toward efficient photovoltaic devices and other optoelectronic devices; however, extraction of charge carriers remains difficult. Herein, we extract photocharges from Ag2S QDs and investigate the dependence of the electric field on the extraction of charges from multiple exciton generation (MEG). Low toxic Ag2S QDs are directly grown on TiO2 mesoporous substrates by employing the successive ionic layer adsorption and reaction (SILAR) method. The contact between QDs is important for the initial charge separation after MEG and for the carrier transport, and the space between neighbor QDs decreases with more SILAR cycles, resulting in better charge extraction. At the optimal electric field for extraction of photocharges, the results suggest that the threshold energy (hνth) for MEG is 2.41Eg. The results reveal that Ag2S QD is a promising material for efficient extraction of charges from MEG and that QDs prepared by SILAR have an advantageous electrical contact facilitating charge separation and extraction.

  3. Determination of hot carrier energy distributions from inversion of ultrafast pump-probe reflectivity measurements.

    Heilpern, Tal; Manjare, Manoj; Govorov, Alexander O; Wiederrecht, Gary P; Gray, Stephen K; Harutyunyan, Hayk

    2018-05-10

    Developing a fundamental understanding of ultrafast non-thermal processes in metallic nanosystems will lead to applications in photodetection, photochemistry and photonic circuitry. Typically, non-thermal and thermal carrier populations in plasmonic systems are inferred either by making assumptions about the functional form of the initial energy distribution or using indirect sensors like localized plasmon frequency shifts. Here we directly determine non-thermal and thermal distributions and dynamics in thin films by applying a double inversion procedure to optical pump-probe data that relates the reflectivity changes around Fermi energy to the changes in the dielectric function and in the single-electron energy band occupancies. When applied to normal incidence measurements our method uncovers the ultrafast excitation of a non-Fermi-Dirac distribution and its subsequent thermalization dynamics. Furthermore, when applied to the Kretschmann configuration, we show that the excitation of propagating plasmons leads to a broader energy distribution of electrons due to the enhanced Landau damping.

  4. Substitute Energy Carriers from Refinement of Coal using HTR-Module

    Barnert, Heiko; Kugeler, Kurt; Will, Michael

    2014-01-01

    There is a revival of coal refinement in the world: a recent press article in Germany titled “The Renaissance of Coal Refinement”. It reports about a large number of conventional plans and plants for coal refinement in many countries in the world, and in particular in China. Nuclear energy can be of assistance, in particular the High Temperature Reactor-Module, because it offers all needed process energies. The status of the research, development, and demonstration, RDD, of technology is summarized, in particular of the former programs in Germany: The primary energy carriers were hard coal and lignite. The envisaged products were: Substitute Natural Gas, SNG, for the gas market, Hydrogen, H2, for a future H2-market, e.g. for airplane traffic, Liquid Fuels, as Substitute Gasoline, or as Energy Alcohol, e.g. Methanol CH3OH, in mixture with higher alcohols, for the car traffic and for home heating. (author)

  5. Immobilization of yeast cells with ionic hydrogel carriers by adhesion-multiplication.

    Zhaoxin, L; Fujimura, T

    2000-12-01

    The mixture of an ionic monomer, 2-acrylamido 2-methylpropanesulfonic acid (TBAS), and a series of poly(ethylene glycol) dimethacrylate (nG) monomers were copolymerized with 60Co gamma-rays, and the produced ionic hydrogel polymers were used for immobilization of yeast cells. The cells were adhered onto the surface of the hydrogel polymers and intruded into the interior of the polymers with growing. The immobilized yeast cells with these hydrogel polymers had higher ethanol productivity than that of free cells. The yield of ethanol with poly(TBAS-14G) carrier was the highest and increased by 3.5 times compared to the free cells. It was found that the ethanol yield increased with the increase of glycol number in poly(ethylene glycol) dimethacrylate. The state of the immobilized cells was observed with microscope, and it was also found that the difference in the ethanol productivity is mainly due to the difference in the internal structure and properties of polymer carrier, such as surface charge, hydrophilicity, and swelling ability of polymer carrier.

  6. Tackling Energy Loss for High-Efficiency Organic Solar Cells with Integrated Multiple Strategies.

    Zuo, Lijian; Shi, Xueliang; Jo, Sae Byeok; Liu, Yun; Lin, Fracis; Jen, Alex K-Y

    2018-04-01

    Limited by the various inherent energy losses from multiple channels, organic solar cells show inferior device performance compared to traditional inorganic photovoltaic techniques, such as silicon and CuInGaSe. To alleviate these fundamental limitations, an integrated multiple strategy is implemented including molecular design, interfacial engineering, optical manipulation, and tandem device construction into one cell. Considering the close correlation among these loss channels, a sophisticated quantification of energy-loss reduction is tracked along with each strategy in a perspective to reach rational overall optimum. A novel nonfullerene acceptor, 6TBA, is synthesized to resolve the thermalization and V OC loss, and another small bandgap nonfullerene acceptor, 4TIC, is used in the back sub-cell to alleviate transmission loss. Tandem architecture design significantly reduces the light absorption loss, and compensates carrier dynamics and thermalization loss. Interfacial engineering further reduces energy loss from carrier dynamics in the tandem architecture. As a result of this concerted effort, a very high power conversion efficiency (13.20%) is obtained. A detailed quantitative analysis on the energy losses confirms that the improved device performance stems from these multiple strategies. The results provide a rational way to explore the ultimate device performance through molecular design and device engineering. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Near-Infrared Resonance Energy Transfer Glucose Biosensors in Hybrid Microcapsule Carriers

    Mike McShane

    2008-09-01

    Full Text Available Fluorescence-based sensing systems offer potential for noninvasive monitoring with implantable devices, but require carrier technologies that provide suitable immobilization, accessibility, and biocompatibility. Recent developments towards this goal include a competitive binding assay for glucose that has been encapsulated in semipermeable microcapsule carriers. This paper describes an extension of this work to increase the applicability to in vivo monitoring, wherein two significant developments are described: (1 a near-infrared resonance energy transfer system for transducing glucose concentration, and (2 novel hybrid organic-inorganic crosslinked microcapsules as carriers. The quenching-based assay is a competitive binding (CB system based on apo-glucose oxidase (AG as the receptor and dextran as the competitive ligand. The encapsulated quencher-labeled dextran and near infrared donor-labeled glucose receptor showed a stable and reversible response with tunable sensitivity of 1–5%/mM over the physiological range, making these transducers attractive for continuous monitoring for biomedical applications.

  8. Production of Solid sustainable Energy Carriers from biomass by means of TORrefaction (SECTOR)

    Witt, Janet; Bienert, Kathrin [DBFZ Deutsches Biomasseforschungszentrum gemeinnuetzige GmbH, Leipzig (Germany). Bereich Bioenergiesysteme; Zwart, Robin; Kiel, Jaap; Englisch, Martin; Wojcik, Magdalena

    2012-07-01

    SECTOR is a large-scale European project with a strong consortium of over 20 partners from industry and science. The project is focussed on the further development of torrefaction-based technologies for the production of solid bioenergy carriers up to pilot-plant scale and beyond, and on supporting the market introduction of torrefaction-based bioenergy carriers as a commodity renewable solid fuel. The torrefaction of biomass materials is considered to be a very promising technology for the promotion of the large-scale implementation of bioenergy. During torrefaction biomass is heated up in the absence of oxygen to a temperature of 250-320 C. By combining torrefaction with pelletisation or briquetting, biomass materials can be converted into a high-energy-density commodity solid fuel or bioenergy carrier with improved behaviour in (long-distance) transport, handling and storage, and also with superior properties in many major end-use applications. Torrefaction has the potential to provide a significant contribution to an enlarged raw material portfolio for biomass fuel production inside Europe by including both agricultural and forestry biomass. In this way, the SECTOR project is expected to shorten the time-to-market of torrefaction technology and to promote market introduction within stringent sustainability boundary conditions. The European Union provides funding for this project within the Seventh Framework Programme. The project has a duration of 42 months and started in January 2012. (orig.)

  9. Laser energy tuning of carrier effective mass and thermopower in epitaxial oxide thin films

    Abutaha, Anas I.

    2012-04-18

    The effect of the laser fluence on high temperature thermoelectric properties of the La doped SrTiO3 (SLTO) thin films epitaxially grown on LaAlO3 〈100〉 substrates by pulsed laser deposition is clarified. It is shown that oxygen vacancies that influence the effective mass of carriers in SLTO films can be tuned by varying the laser energy. The highest power factor of 0.433 W K−1 m−1 has been achieved at 636 K for a filmdeposited using the highest laser fluence of 7 J cm−2 pulse−1.

  10. Multifunctional Amine Mesoporous Silica Spheres Modified with Multiple Amine as Carriers for Drug Release

    Yan Li

    2018-01-01

    Full Text Available Mesoporous silica spheres were synthesized by using Stöber theory (MSN-40. Calcination of the mesostructured phase resulted in the starting solid. Organic modification with aminopropyl groups resulted in two MSN-40 materials: named MSN-NH2 and MSN-DQ-40, respectively. These two kinds of samples with different pore sizes (obtained from 3-[2-(2-aminoethylaminoethylamino]propyl-trimethox-ysilane (NQ-62 and modified NQ-62 showed control of the delivery rate of ibuprofen (IBU from the siliceous matrix. The obtained sample from modified NQ-62 has an increased loading rate and shows better control of the delivery rate of IBU than the obtained sample from NQ-62. These three solids were characterized using standard solid state procedures. During tests of in vitro drug release, an interesting phenomenon was observed: at high pH (pH 7.45, IBU in all carriers was released slowly; at low pH (pH 4.5, only a part of the IBU was slowly released from this carrier within 25 hours; most IBU was effectively confined in mesoporous material, but the remaining IBU was released rapidly and completely after 25 hours.

  11. Opportunistic Carrier Sensing for Energy-Efficient Information Retrieval in Sensor Networks

    Zhao Qing

    2005-01-01

    Full Text Available We consider distributed information retrieval for sensor networks with cluster heads or mobile access points. The performance metric used in the design is energy efficiency defined as the ratio of the average number of bits reliably retrieved by the access point to the total amount of energy consumed. A distributed opportunistic transmission protocol is proposed using a combination of carrier sensing and backoff strategy that incorporates channel state information (CSI of individual sensors. By selecting a set of sensors with the best channel states to transmit, the proposed protocol achieves the upper bound on energy efficiency when the signal propagation delay is negligible. For networks with substantial propagation delays, a backoff function optimized for energy efficiency is proposed. The design of this backoff function utilizes properties of extreme statistics and is shown to have mild performance loss in practical scenarios. We also demonstrate that opportunistic strategies that use CSI may not be optimal when channel acquisition at individual sensors consumes substantial energy. We show further that there is an optimal sensor density for which the opportunistic information retrieval is the most energy efficient. This observation leads to the design of the optimal sensor duty cycle.

  12. Multiple Energy System Analysis of Smart Energy Systems

    Thellufsen, Jakob Zinck

    2015-01-01

    thermal grids and smart gas grids, Smart Energy Systems moves the flexibility away from the fuel as is the case in current energy systems and into the system itself. However, most studies applying a Smart Energy System approach deals with analyses for either single countries or whole continents......To eliminate the use of fossil fuels in the energy sector it is necessary to transition to future 100% renewable energy systems. One approach for this radical change in our energy systems is Smart Energy Systems. With a focus on development and interaction between smart electricity grids, smart......, but it is unclear how regions, municipalities, and communities should deal with these national targets. It is necessary to be able to provide this information since Smart Energy Systems utilize energy resources and initiatives that have strong relations to local authorities and communities, such as onshore wind...

  13. Kinetic energy dependence of carrier diffusion in a GaAs epilayer studied by wavelength selective PL imaging

    Zhang, S. [University of North Carolina at Charlotte, Charlotte, NC 28223 (United States); Providence High School, Charlotte, NC 28270 (United States); Su, L.Q.; Kon, J. [University of North Carolina at Charlotte, Charlotte, NC 28223 (United States); Gfroerer, T. [Davidson College, Davidson, NC 28035 (United States); Wanlass, M.W. [National Renewable Energy Laboratory, Golden, CO 80401 (United States); Zhang, Y., E-mail: yong.zhang@uncc.edu [University of North Carolina at Charlotte, Charlotte, NC 28223 (United States)

    2017-05-15

    Photoluminescence (PL) imaging has been shown to be an efficient technique for investigating carrier diffusion in semiconductors. In the past, the measurement was typically carried out by measuring at one wavelength (e.g., at the band gap) or simply the whole emission band. At room temperature in a semiconductor like GaAs, the band-to-band PL emission may occur in a spectral range over 200 meV, vastly exceeding the average thermal energy of about 26 meV. To investigate the potential dependence of the carrier diffusion on the carrier kinetic energy, we performed wavelength selective PL imaging on a GaAs double hetero-structure in a spectral range from about 70 meV above to 50 meV below the bandgap, extracting the carrier diffusion lengths at different PL wavelengths by fitting the imaging data to a theoretical model. The results clearly show that the locally generated carriers of different kinetic energies mostly diffuse together, maintaining the same thermal distribution throughout the diffusion process. Potential effects related to carrier density, self-absorption, lateral wave-guiding, and local heating are also discussed.

  14. Photo-generated carriers lose energy during extraction from polymer-fullerene solar cells

    Melianas, Armantas; Etzold, Fabian; Savenije, Tom J.; Laquai, Fré dé ric; Inganä s, Olle; Kemerink, Martijn

    2015-01-01

    motion is boosted by this process, leading to a time-dependent carrier mobility as confirmed by direct experiments. We identify the time and distance scales relevant for carrier extraction and show that the photo-generated carriers are extracted from

  15. Power-generating process of obtaining gas-energy carrier and reducer from coal

    Tleugabulov, S.; Duncheva, E.; Zubkevich, M.

    1999-01-01

    The manufacture of power-generating gas has the important economic value for Kazakhstan having large territory, raw and fuel resources especially power coal and clean coal wastes. The technology of reception of gas-energy carrier and reducer from power coal is developed. The basic product of technological process is heated reducing gas. Reducing potential of the gas is characterized by a volumetric share of components (CO+H 2 )-RC in relation to volume of whole mix of gases received with gasification of coal. The value of parameter RC is regulated by a degree of enrichment of air by oxygen r 0 , and the temperature - by the charge of a parity of endothermic reaction in the chamber of gas regeneration. The dependence of the gas structure and temperature on the degree of enrichment of air by oxygen is shown and the circuit of the gas generator is given. (author)

  16. Optically Discriminating Carrier-Induced Quasiparticle Band Gap and Exciton Energy Renormalization in Monolayer MoS_{2}.

    Yao, Kaiyuan; Yan, Aiming; Kahn, Salman; Suslu, Aslihan; Liang, Yufeng; Barnard, Edward S; Tongay, Sefaattin; Zettl, Alex; Borys, Nicholas J; Schuck, P James

    2017-08-25

    Optoelectronic excitations in monolayer MoS_{2} manifest from a hierarchy of electrically tunable, Coulombic free-carrier and excitonic many-body phenomena. Investigating the fundamental interactions underpinning these phenomena-critical to both many-body physics exploration and device applications-presents challenges, however, due to a complex balance of competing optoelectronic effects and interdependent properties. Here, optical detection of bound- and free-carrier photoexcitations is used to directly quantify carrier-induced changes of the quasiparticle band gap and exciton binding energies. The results explicitly disentangle the competing effects and highlight longstanding theoretical predictions of large carrier-induced band gap and exciton renormalization in two-dimensional semiconductors.

  17. Optically Discriminating Carrier-Induced Quasiparticle Band Gap and Exciton Energy Renormalization in Monolayer MoS2

    Yao, Kaiyuan; Yan, Aiming; Kahn, Salman; Suslu, Aslihan; Liang, Yufeng; Barnard, Edward S.; Tongay, Sefaattin; Zettl, Alex; Borys, Nicholas J.; Schuck, P. James

    2017-08-01

    Optoelectronic excitations in monolayer MoS2 manifest from a hierarchy of electrically tunable, Coulombic free-carrier and excitonic many-body phenomena. Investigating the fundamental interactions underpinning these phenomena—critical to both many-body physics exploration and device applications—presents challenges, however, due to a complex balance of competing optoelectronic effects and interdependent properties. Here, optical detection of bound- and free-carrier photoexcitations is used to directly quantify carrier-induced changes of the quasiparticle band gap and exciton binding energies. The results explicitly disentangle the competing effects and highlight longstanding theoretical predictions of large carrier-induced band gap and exciton renormalization in two-dimensional semiconductors.

  18. Generalized dark energy interactions with multiple fluids

    De Bruck, Carsten van; Mifsud, Jurgen [Consortium for Fundamental Physics, School of Mathematics and Statistics, University of Sheffield, Hounsfield Road, Sheffield S3 7RH (United Kingdom); Mimoso, José P.; Nunes, Nelson J., E-mail: c.vandebruck@sheffield.ac.uk, E-mail: jmifsud1@sheffield.ac.uk, E-mail: jpmimoso@fc.ul.pt, E-mail: njnunes@fc.ul.pt [Instituto de Astrofísica e Ciências do Espaço, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, PT1749-016 Lisboa (Portugal)

    2016-11-01

    In the search for an explanation for the current acceleration of the Universe, scalar fields are the most simple and useful tools to build models of dark energy. This field, however, must in principle couple with the rest of the world and not necessarily in the same way to different particles or fluids. We provide the most complete dynamical system analysis to date, consisting of a canonical scalar field conformally and disformally coupled to both dust and radiation. We perform a detailed study of the existence and stability conditions of the systems and comment on constraints imposed on the disformal coupling from Big-Bang Nucleosynthesis and given current limits on the variation of the fine-structure constant.

  19. Hydrogen as an energy carrier. Final report; Wasserstoff als Energietraeger. Abschlussbericht

    Rebholz, H. [ed.

    1998-12-01

    This final report of the Special Field of Research 270 (SFB 270) documents the work and results of the four promotion phases from 1989 to 1998, presented in reports on 15 part-projects. From its inception, SFB 270, which bears the title ''Hydrogen as an Energy Carrier'', has been dedicated to two fields of work: in Project Area A to the production of hydrogen (7 part-projects) and in Project Area B to the transport and storage of hydrogen (8 part-projects). The scientific results of the part-projects have also been presented in detail in the progress reports and interim reports of 1991, 1994 and 1997. Some of them have also been presented at the colloquiums of SFB 270. Twelve part-projects have been abstracted individually for the ENERGY database. [German] Der vorliegende Abschlussbericht des Sonderforschungsbereichs 270 dokumentiert die Arbeiten und Ergebnisse der vier Foerderungsphasen von 1989 bis 1998. Sie sind in den Berichten von 15 Teilprojekten wiedergegeben. Der Sonderforschungsbereich 270 'Wasserstoff als Energietraeger' hat sich von Anfang an zwei Aufgabengebieten gewidmet: Im Projektbereich A der Herstellung von Wasserstoff (7 Teilprojekte) und im Projektbereich B dem Transport und der Speicherung von Wasserstoff (8 Teilprojekte). Wissenschaftliche Ergebnisse der Teilprojekte sind ausfuehrlich auch in den Arbeits- und Ergebnisberichten 1991, 1994 und 1997 wiedergegeben. Sie wurden auch, in Teilen, in entsprechenden Kolloquien des SFB 270 praesentiert. Fuer die Datenbank ENERGY wurden 12 Teilprojekte separat aufgenommen. (orig.)

  20. Hydrogen as an energy carrier in substituting petroleum. Demonstration project: automobiles driven by nuclear energy

    Donne, M.D.; Dorner, S.; Kessler, G.; Schretzmann, K.

    1983-01-01

    The substitution of oil in motor vehicles by means of coal upgrading is paid by a consumption of primary energy and the persistence of a high environmental impact as noise and off-gases. Alternative systems, based on electric traction by electricity from H 2 -fuel cells have a high development potential. The Karlsruhe Nuclear Center has endeavoured to demonstrate the feasibility of this traction system. In particular an assessment of the efficiency and costs of the H 2 -fuel cell for vehicle traction is given. The paper discusses the various possibilities of on-board H 2 storage. Finally the work being presently performed in Karlsruhe is briefly described. (author)

  1. Multiple-choice test of energy and momentum concepts

    Singh, Chandralekha; Rosengrant, David

    2016-01-01

    We investigate student understanding of energy and momentum concepts at the level of introductory physics by designing and administering a 25-item multiple choice test and conducting individual interviews. We find that most students have difficulty in qualitatively interpreting basic principles related to energy and momentum and in applying them in physical situations.

  2. Identification of deep trap energies and influences of oxygen plasma ashing on semiconductor carrier lifetime

    Koprowski, A; Humbel, O; Plappert, M; Krenn, H

    2015-01-01

    We have performed an analytical study of the effects of oxygen plasma ashing processes in semiconductor device fabrication and its impact on minority carrier lifetime in high voltage semiconductor devices. Our work includes a critical background study of life time killing mechanisms by deep traps imparted into the semiconductor by barrel plasma ashing. The Elymat technique provides the opportunity to measure lifetime and diffusion length of minority carriers and surface photo voltage (SPV) measurement was used to analyse influences of process parameters such as photoresist, time budget and positioning in the process chamber. It was shown that in microwave plasma processes the diffusion length changes severely with tempering at 200 °C, whereas RF-plasma processes show a significant process time-dependence. Batch tools in general suffer from a strong first wafer effect which could be correlated with the static electrical parameters of the semiconductor devices. The trap identities were detected by using deep level transient spectroscopy and the chemical species of the traps has been proven by inductive coupled plasma mass spectrometry. The deep-bandgap trap energies are reliable fingerprints of the chosen process parameters such as process time and of resist-influences. By microwave plasma processes intrinsic Fe and FeB-complex levels were identified and a good agreement with the SPV-measurement and electrical device characteristic was shown. RF-plasma processes impart levels attributed to Pt levels and an additional level, which could be identified as a trap level probably forming a complex of Pt and H. (paper)

  3. Economic impacts of hydrogen as an energy carrier in European countries

    Wietschel, Martin; Seydel, Philipp

    2007-01-01

    The two objectives of this paper are to identify possible sectoral shifts and employment effects due to the application of hydrogen in the energy system for selected European countries till 2030. This is based on assumptions about the market penetration of hydrogen as an energy carrier, an analysis of the competitiveness of EU countries in this technology field and input-output model calculations. The analysis showed that the introduction of hydrogen leads to significant shifts between economic sectors and, as a policy recommendation, it is concluded that the required workforce skills in hydrogen technologies should be available in time in order to be properly prepared for this. Some employment gains are possible for the EU Member States analysed if the introduction of hydrogen does not result in significant changes in export/import flows. However, the lead market analysis also showed that the competitiveness of EU countries varies significantly and that, viewed as a whole, Europe is in danger of falling behind its main competitors. This may lead to job losses because the industry branches affected - automotive and plant manufacturers - represent key sectors for the EU. One policy goal, therefore, especially for countries with a large share of automobile and plant manufacturing, is to aim to be a lead market for hydrogen and fuel cells. (author)

  4. Femtosecond time-resolved hot carrier energy distributions of photoexcited semiconductor quantum dots

    Chuang, Chi-Hung; Burda, Clemens; Chen, Xiaobo

    2013-01-01

    Using femtosecond transient absorption spectroscopy, we investigated hot carrier distributions in semiconductor cadmium selenide quantum dots. The relaxation processes represent the behavior of an ensemble of QDs. This concept is applied for analysis with the Fermi-Dirac distribution and relaxation processes among different electron-hole pair states. By extracting the experimental hot carrier distribution and fitting with the Fermi-Dirac function, we resolved the rapid thermalization processes, such as carrier-carrier and carrier-phonon interactions was resolved within one picosecond upon photoexcitation. The analysis, using the Fermi-Dirac distribution modulated by the density of states, provides a general route to understanding the carrier cooling and heat dissipation processes in quantum dot-based systems. (copyright 2012 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Cooperative Transmission in Mobile Wireless Sensor Networks with Multiple Carrier Frequency Offsets: A Double-Differential Approach

    Kun Zhao

    2014-01-01

    Full Text Available As a result of the rapidly increasing mobility of sensor nodes, mobile wireless sensor networks (MWSNs would be subject to multiple carrier frequency offsets (MCFOs, which result in time-varying channels and drastically degrade the network performance. To enhance the performance of such MWSNs, we propose a relay selection (RS based double-differential (DD cooperative transmission scheme, termed RSDDCT, in which the best relay sensor node is selected to forward the source sensor node’s signals to the destination sensor node with the detect-and-forward (DetF protocol. Assuming a Rayleigh fading environment, first, exact closed-form expressions for the outage probability and average bit error rate (BER of the RSDDCT scheme are derived. Then, simple and informative asymptotic outage probability and average BER expressions at the large signal-to-noise ratio (SNR regime are presented, which reveal that the RSDDCT scheme can achieve full diversity. Furthermore, the optimum power allocation strategy in terms of minimizing the average BER is investigated, and simple analytical solutions are obtained. Simulation results demonstrate that the proposed RSDDCT scheme can achieve excellent performance over fading channels in the presence of unknown random MCFOs. It is also shown that the proposed optimum power allocation strategy offers substantial average BER performance improvement over the equal power allocation strategy.

  6. Excess of extracolonic non-endometrial multiple primary cancers in MSH2 germline mutation carriers over MLH1.

    Lin-Hurtubise, Kevin M; Yheulon, Christopher G; Gagliano, Ronald A; Lynch, Henry T

    2013-12-01

    The lynch syndrome (LS) tumor spectrum involves colorectal cancer (CRC), endometrial cancer (EC), and less frequently various extracolonic non-endometrial cancers (non-EC). The organ-specific survival rates of these patients are well defined, however, the collective survival of all-cancers combined (CRC + EC + non-EC) are unclear. Fifty-two MSH2 patients and 68 MLH1 patients were followed for a median of 6.3 years after diagnosis of first cancer, regardless of type. The proportions of CRC only, EC, non-EC, and multiple primary cancers were compared between the two genotypes. Kaplan-Meier curves were developed for survival comparisons. MSH2 patients present less frequently with only CRC (37% MSH2, 62% MLH1, P = 0.0096), manifest more multiple primary cancers (38% MSH2, 18% MLH1, P = 0.013), develop more extracolonic cancers (62% MSH2, 38% MLH1, P = 0.003), non-EC only cancers (46% MSH2, 24% MLH1, P = 0.028) and carry a greater risk for urinary tract cancer (UTC) (13.4% MSH2, 1.5% MLH1, P = 0.024). There was no difference in 10-year survival between the two groups (P = 0.4). The additional propensity for UTC in MSH2 carriers argues in favor of UTC screening in MSH2 individuals. Other types of cancer screening should be tailored to the expression history of the specific LS mutation. © 2013 Wiley Periodicals, Inc.

  7. Hydrogen peroxide as a sustainable energy carrier: Electrocatalytic production of hydrogen peroxide and the fuel cell

    Fukuzumi, Shunichi; Yamada, Yusuke; Karlin, Kenneth D.

    2012-01-01

    This review describes homogeneous and heterogeneous catalytic reduction of dioxygen with metal complexes focusing on the catalytic two-electron reduction of dioxygen to produce hydrogen peroxide. Whether two-electron reduction of dioxygen to produce hydrogen peroxide or four-electron O 2 -reduction to produce water occurs depends on the types of metals and ligands that are utilized. Those factors controlling the two processes are discussed in terms of metal–oxygen intermediates involved in the catalysis. Metal complexes acting as catalysts for selective two-electron reduction of oxygen can be utilized as metal complex-modified electrodes in the electrocatalytic reduction to produce hydrogen peroxide. Hydrogen peroxide thus produced can be used as a fuel in a hydrogen peroxide fuel cell. A hydrogen peroxide fuel cell can be operated with a one-compartment structure without a membrane, which is certainly more promising for the development of low-cost fuel cells as compared with two compartment hydrogen fuel cells that require membranes. Hydrogen peroxide is regarded as an environmentally benign energy carrier because it can be produced by the electrocatalytic two-electron reduction of O 2 , which is abundant in air, using solar cells; the hydrogen peroxide thus produced could then be readily stored and then used as needed to generate electricity through the use of hydrogen peroxide fuel cells.

  8. Hydrogen Peroxide as a Sustainable Energy Carrier: Electrocatalytic Production of Hydrogen Peroxide and the Fuel Cell.

    Fukuzumi, Shunichi; Yamada, Yusuke; Karlin, Kenneth D

    2012-11-01

    This review describes homogeneous and heterogeneous catalytic reduction of dioxygen with metal complexes focusing on the catalytic two-electron reduction of dioxygen to produce hydrogen peroxide. Whether two-electron reduction of dioxygen to produce hydrogen peroxide or four-electron O 2 -reduction to produce water occurs depends on the types of metals and ligands that are utilized. Those factors controlling the two processes are discussed in terms of metal-oxygen intermediates involved in the catalysis. Metal complexes acting as catalysts for selective two-electron reduction of oxygen can be utilized as metal complex-modified electrodes in the electrocatalytic reduction to produce hydrogen peroxide. Hydrogen peroxide thus produced can be used as a fuel in a hydrogen peroxide fuel cell. A hydrogen peroxide fuel cell can be operated with a one-compartment structure without a membrane, which is certainly more promising for the development of low-cost fuel cells as compared with two compartment hydrogen fuel cells that require membranes. Hydrogen peroxide is regarded as an environmentally benign energy carrier because it can be produced by the electrocatalytic two-electron reduction of O 2 , which is abundant in air, using solar cells; the hydrogen peroxide thus produced could then be readily stored and then used as needed to generate electricity through the use of hydrogen peroxide fuel cells.

  9. More Wind Power Integration with Adjusted Energy Carriers for Space Heating in Northern China

    Jianjun He

    2012-08-01

    Full Text Available In Northern China, due to the high penetration of coal-fired cogeneration facilities, which are generally equipped with extraction-condensing steam turbines, lots of wind power resources may be wasted during the heating season. In contrast, considerable coal is consumed in the power generation sector. In this article, firstly it is revealed that there exists a serious divergence in the ratio of electrical to thermal energy between end users’ demand and the cogenerations’ production during off-peak load at night, which may negate active power-balancing of the electric power grid. Secondly, with respect to this divergence only occurring during off-peak load at night, a temporary proposal is given so as to enable the integration of more wind power. The authors suggest that if the energy carrier for part of the end users’ space heating is switched from heating water to electricity (e.g., electric heat pumps (EHPs can provide space heating in the domestic sector, the ratio of electricity to heating water load should be adjusted to optimize the power dispatch between cogeneration units and wind turbines, resulting in fuel conservation. With this proposal, existing infrastructures are made full use of, and no additional ones are required. Finally a numerical simulation is performed in order to illustrate both the technical and economic feasibility of the aforementioned proposal, under ongoing infrastructures as well as electricity and space heating tariff conditions without changing participants’ benefits. The authors aim to persuade Chinese policy makers to enable EHPs to provide space heating to enable the integration of more wind power.

  10. What is required to make hydrogen a real energy carrier option?

    Braeuninger, S.; Schindler, G.; Schwab, E.; Weck, A. [BASF SE, Ludwigshafen (Germany)

    2010-12-30

    The driver for the introduction of hydrogen as mobile energy-carrier is regulatory measures to avoid the CO{sub 2} emissions which are related to the current fossil carbon based situation. H{sub 2} is a large volume chemical product with an annual production of about 45 million tons, most of which currently is also derived from fossil sources. The German transport sector consumes 2,6.10{sup 12} MJ/a which in terms of energy is equivalent to nearly 50% of the current world hydrogen production. There is the proposal to start the ''hydrogen economy'' with ''excess H{sub 2}'' which is believed to be available as inadvertently occurring byproduct of chemical processes. A potential {proportional_to}2 million tons is estimated for this ''excess H{sub 2}'' in Europe; the proposal however does not take into account, that current uses of this H{sub 2} would have to be substituted. Therefore, an overall gain for the environment cannot be expected. Therefore, a sustainable hydrogen based energy scenario has to rely on new sources. Besides Biomass gasification which in terms of technology would resemble the conventional fossil based hydrogen production, the only other viable carbon-free hydrogen source is water, which has to be split into its constituting elements. The current paper is restricted to the latter path, the feasibility of the biomass approach needs to be discussed elsewhere. If hypothetically the above mentioned energy for the German transport sector would be provided by H{sub 2} from water electrolysis an electricity input of 4.10{sup 12} MJ would be needed. This number exceeds the currently installed German wind turbine capacity by a factor of 6 and even by a factor of 36, if the weather-based {proportional_to}16% year-round on-stream factor for onshore plants is taken into account. (orig.)

  11. Use of natural gas, methanol, and ethanol fuel emulsions as environmentally friendly energy carriers for mobile heat power plants

    Likhanov, V. A.; Lopatin, O. P.

    2017-12-01

    The need for using environmentally friendly energy carriers for mobile heat power plants (HPPs) is grounded. Ecologically friendly sources of energy, such as natural gas as well as renewable methyl and ethyl alcohols, are investigated. In order to develop, determine, and optimize the composition of environmentally friendly energy carriers for an HPP, the latter has been tested when working on diesel fuel (DF), compressed natural gas (CNG), and methanol and ethanol fuel emulsions (MFE, EFE). It has been experimentally established that, for the application of environmentally friendly energy carriers for a 4Ch 11.0/12.5 diesel engine of a mobile fuel and power plant, it is necessary to maintain the following ratio of components when working on CNG: 80% gas and 20% DF primer portion. When working on an alcohol mixture, emulsions of the following composition were used: 25% alcohol (methanol or ethanol), 0.5% detergent-dispersant additive succinimide C-5A, 7% water, and 67.5% DF. When this diesel passed from oil DF to environmentally friendly energy sources, it allowed for the reduction of the content of exhaust gases (EG) (1) when working on CNG with recirculation of exhaust gases (EGR) (recirculation was used to eliminate the increased amount of nitric oxides by using CNG): carbon black by 5.8 times, carbon dioxide by 45.9%, and carbon monoxide by 23.8%; (2) when working on MFE: carbon black by 6.4 times, nitrogen oxides by 29.6%, carbon dioxide by 10.1%, and carbon oxide by 47.6%; (3) when working on EFE: carbon black by 4.8 times; nitrogen oxides by 40.3%, carbon dioxide by 26.6%, and carbon monoxide by 28.6%. The prospects of use of environmentally friendly energy carriers in diesels of mobile HPPs, such as natural gas, ethanol, and methanol, has been determined.

  12. Multiple origins of hydrogenosomes: functional and phylogenetic evidence from the ADP/ATP carrier of the anaerobic chytrid Neocallimastix sp.

    Voncken, F.L.M.; Boxma, B.; Tjaden, J.; Akhmanova, A.S.; Huynen, M.A.; Verbeek, F.; Tielens, A.G.; Haferkamp, I.; Neuhaus, H.E.; Vogels, G.D.; Veenhuis, M.; Hackstein, J.H.P.

    2002-01-01

    A mitochondrial-type ADP/ATP carrier (AAC) has been identified in the hydrogenosomes of the anaerobic chytridiomycete fungus Neocallimastix sp. L2. Biochemical and immunocytochemical studies revealed that this ADP/ATP carrier is an integral component of hydrogenosomal membranes. Expression of the

  13. Multiple origins of hydrogenosomes : functional and phylogenetic evidence from the ADP/ATP carrier of the anaerobic chytrid Neocallimastix sp.

    Voncken, F; Boxma, B; Tjaden, J; Akhmanova, A; Huynen, M; Tielens, AGM; Haferkamp, [No Value; Neuhaus, HE; Vogels, G; Veenhuis, M; Hackstein, JHP; Tielens, Aloysius G.M.; Haferkamp, Ilka; Hackstein, Johannes H.P.

    A mitochondrial-type ADP/ATP carrier (AAC) has been identified in the hydrogenosomes of the anaerobic chytridiomycete fungus Neocallimastix sp. L2. Biochemical and immunocytochemical studies revealed that this ADP/ATP carrier is an integral component of hydrogenosomal membranes. Expression of the

  14. Simultaneous energy harvesting and information processing in wireless multiple relays with multiple antennas

    Albaaj, Azhar; Makki, S. Vahab A.; Alabkhat, Qassem; Zahedi, Abdulhamid

    2017-07-01

    Wireless networks suffer from battery discharging specially in cooperative communications when multiple relays have an important role but they are energy constrained. To overcome this problem, energy harvesting from radio frequency signals is applied to charge the node battery. These intermediate nodes have the ability to harvest energy from the source signal and use the energy harvested to transmit information to the destination. In fact, the node tries to harvest energy and then transmit the data to destination. Division of energy harvesting and data transmission can be done in two algorithms: time-switching-based relaying protocol and power-splitting-based relaying protocol. These two algorithms also can be applied in delay-limited and delay-tolerant transmission systems. The previous works have assumed a single relay for energy harvesting, but in this article, the proposed method is concentrated on improving the outage probability and throughput by using multiple antennas in each relay node instead of using single antenna. According to our simulation results, when using multi-antenna relays, ability of energy harvesting is increased and thus system performance will be improved to great extent. Maximum ratio combining scheme has been used when the destination chooses the best signal of relays and antennas satisfying the required signal-to-noise ratio.

  15. Energy prices, multiple structural breaks, and efficient market hypothesis

    Lee, Chien-Chiang; Lee, Jun-De [Department of Applied Economics, National Chung Hsing University, Taichung (China)

    2009-04-15

    This paper investigates the efficient market hypothesis using total energy price and four kinds of various disaggregated energy prices - coal, oil, gas, and electricity - for OECD countries over the period 1978-2006. We employ a highly flexible panel data stationarity test of Carrion-i-Silvestre et al. [Carrion-i-Silvestre JL, Del Barrio-Castro T, Lopez-Bazo E. Breaking the panels: an application to GDP per capita. J Econometrics 2005;8:159-75], which incorporates multiple shifts in level and slope, thereby controlling for cross-sectional dependence through bootstrap methods. Overwhelming evidence in favor of the broken stationarity hypothesis is found, implying that energy prices are not characterized by an efficient market. Thus, it shows the presence of profitable arbitrage opportunities among energy prices. The estimated breaks are meaningful and coincide with the most critical events which affected the energy prices. (author)

  16. Energy prices, multiple structural breaks, and efficient market hypothesis

    Lee, Chien-Chiang; Lee, Jun-De

    2009-01-01

    This paper investigates the efficient market hypothesis using total energy price and four kinds of various disaggregated energy prices - coal, oil, gas, and electricity - for OECD countries over the period 1978-2006. We employ a highly flexible panel data stationarity test of Carrion-i-Silvestre et al. [Carrion-i-Silvestre JL, Del Barrio-Castro T, Lopez-Bazo E. Breaking the panels: an application to GDP per capita. J Econometrics 2005;8:159-75], which incorporates multiple shifts in level and slope, thereby controlling for cross-sectional dependence through bootstrap methods. Overwhelming evidence in favor of the broken stationarity hypothesis is found, implying that energy prices are not characterized by an efficient market. Thus, it shows the presence of profitable arbitrage opportunities among energy prices. The estimated breaks are meaningful and coincide with the most critical events which affected the energy prices. (author)

  17. Sleep Management on Multiple Machines for Energy and Flow Time

    Chan, Sze-Hang; Lam, Tak-Wah; Lee, Lap Kei

    2011-01-01

    In large data centers, determining the right number of operating machines is often non-trivial, especially when the workload is unpredictable. Using too many machines would waste energy, while using too few would affect the performance. This paper extends the traditional study of online flow-time...... scheduling on multiple machines to take sleep management and energy into consideration. Specifically, we study online algorithms that can determine dynamically when and which subset of machines should wake up (or sleep), and how jobs are dispatched and scheduled. We consider schedules whose objective...... is to minimize the sum of flow time and energy, and obtain O(1)-competitive algorithms for two settings: one assumes machines running at a fixed speed, and the other allows dynamic speed scaling to further optimize energy usage. Like the previous work on the tradeoff between flow time and energy, the analysis...

  18. Radiative recombination mechanism of carriers in InGaN/AlInGaN multiple quantum wells with varying aluminum content

    Liu, Tong [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Jiao, Shujie, E-mail: shujiejiao@gmail.com [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Key Laboratory for Photonic and Electric Bandgap Materials, Ministry of Education, Harbin Normal University, Harbin 150001 (China); Key Laboratory of Nanodevices and Applications, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123 (China); Wang, Dongbo [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Gao, Shiyong, E-mail: gaoshiyong@hit.edu.cn [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China); Yang, Tianpeng [EpiTop Optoelectronic Co., Ltd., Pingxiang 337000 (China); Liang, Hongwei [School of Physics and Optoelectronic Engineering, Dalian University of Technology, Dalian 116024 (China); Zhao, Liancheng [School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001 (China)

    2015-02-05

    Highlights: • Structural and optical properties of In GaN/Al{sub x}In{sub y}Ga{sub 1−x−y}N MQWs were investigated. • The existence of In-rich clusters has been verified by Raman spectra. • The degree of localization effect increase with increasing Al content in barriers. • The origin of the deep localized states could be assigned to the larger QCSE. • Recombination mechanism of carriers with increasing temperature has been proposed. - Abstract: The structural and optical properties of In{sub 0.20}Ga{sub 0.80}N/Al{sub x}In{sub y}Ga{sub 1−x−y}N multiple quantum wells samples with varying Al content in barrier layers grown on sapphire substrates by metalorganic chemical vapor deposition have been investigated by means of high-resolution X-ray diffraction, Raman scattering measurements and temperature-dependent photoluminescence. Raman measurements verified the existence of In-rich clusters in ternary and quaternary layers. At 10 K and 300 K, the PL spectrum of each sample is dominated by a sharp emission peak arising from In{sub 0.20}Ga{sub 0.80}N well layers. The anomalous temperature-dependent S-shaped behaviors of emission energies have been observed, indicating the presence of localized states induced by the potential fluctuations in the quantum wells due to the inhomogeneous distribution of In-rich clusters. The degree of the localization effect and the transition temperatures between different temperature regions can be enhanced by increasing Al content in barrier layers. The improvement of the localized states emission has been observed at the lower energy side of band gap emission of quantum wells with increasing Al content. The origin of the deep localized states could be attributed to the larger quantum-confined Stark effect in the quantum wells with higher Al content. The recombination mechanism of carriers between band edge and localized states was proposed for interpreting of the emission characteristics.

  19. Muon energy estimate through multiple scattering with the MACRO detector

    Ambrosio, M.; Antolini, R.; Auriemma, G.; Bakari, D.; Baldini, A.; Barbarino, G.C.; Barish, B.C.; Battistoni, G.; Becherini, Y.; Bellotti, R.; Bemporad, C.; Bernardini, P.; Bilokon, H.; Bloise, C.; Bower, C.; Brigida, M.; Bussino, S.; Cafagna, F.; Calicchio, M.; Campana, D.; Candela, A.; Carboni, M.; Caruso, R.; Cassese, F.; Cecchini, S.; Cei, F.; Chiarella, V.; Choudhary, B.C.; Coutu, S.; Cozzi, M.; De Cataldo, G.; De Deo, M.; Dekhissi, H.; De Marzo, C.; De Mitri, I.; Derkaoui, J.; De Vincenzi, M.; Di Credico, A.; Dincecco, M.; Erriquez, O.; Favuzzi, C.; Forti, C.; Fusco, P.; Giacomelli, G.; Giannini, G.; Giglietto, N.; Giorgini, M.; Grassi, M.; Gray, L.; Grillo, A.; Guarino, F.; Gustavino, C.; Habig, A.; Hanson, K.; Heinz, R.; Iarocci, E.; Katsavounidis, E.; Katsavounidis, I.; Kearns, E.; Kim, H.; Kyriazopoulou, S.; Lamanna, E.; Lane, C.; Levin, D.S.; Lindozzi, M.; Lipari, P.; Longley, N.P.; Longo, M.J.; Loparco, F.; Maaroufi, F.; Mancarella, G.; Mandrioli, G.; Margiotta, A.; Marini, A.; Martello, D.; Marzari-Chiesa, A.; Mazziotta, M.N.; Michael, D.G.; Monacelli, P.; Montaruli, T.; Monteno, M.; Mufson, S.; Musser, J.; Nicolo, D.; Nolty, R.; Orth, C.; Osteria, G.; Palamara, O.; Patera, V.; Patrizii, L.; Pazzi, R.; Peck, C.W.; Perrone, L.; Petrera, S.; Pistilli, P.; Popa, V.; Raino, A.; Reynoldson, J.; Ronga, F.; Rrhioua, A.; Satriano, C.; Scapparone, E. E-mail: eugenio.scapparone@bo.infn.it; Scholberg, K.; Sciubba, A.; Serra, P.; Sioli, M. E-mail: maximiliano.sioli@bo.infn.it; Sirri, G.; Sitta, M.; Spinelli, P.; Spinetti, M.; Spurio, M.; Steinberg, R.; Stone, J.L.; Sulak, L.R.; Surdo, A.; Tarle, G.; Tatananni, E.; Togo, V.; Vakili, M.; Walter, C.W.; Webb, R

    2002-10-21

    Muon energy measurement represents an important issue for any experiment addressing neutrino-induced up-going muon studies. Since the neutrino oscillation probability depends on the neutrino energy, a measurement of the muon energy adds an important piece of information concerning the neutrino system. We show in this paper how the MACRO limited streamer tube system can be operated in drift mode by using the TDCs included in the QTPs, an electronics designed for magnetic monopole search. An improvement of the space resolution is obtained, through an analysis of the multiple scattering of muon tracks as they pass through our detector. This information can be used further to obtain an estimate of the energy of muons crossing the detector. Here we present the results of two dedicated tests, performed at CERN PS-T9 and SPS-X7 beam lines, to provide a full check of the electronics and to exploit the feasibility of such a multiple scattering analysis. We show that by using a neural network approach, we are able to reconstruct the muon energy for E{sub {mu}}<40 GeV. The test beam data provide an absolute energy calibration, which allows us to apply this method to MACRO data.

  20. Program energy research and energy technologies. Annual report 1987. Fossil energy carriers, renewable energy sources, efficient use of energy. Programm Energieforschung und Energietechnologien. Jahresbericht 1987. Fossile Energietraeger, erneuerbare Energiequellen, rationelle Energieverwendung

    1988-01-01

    After a general introduction and a short overview of financial contributions in 1987 there is a description of the projects sponsored. The main section contains project descriptions of the partial programmes Fossil Energy Carriers, Renewable Energy Sources and Efficient Use of Energy. The ordering of the wide-ranging material is carried out essentially via two indices: the index of project numbers and the index of companies. Then an overview is given of final reports published in 1987. A list of 1987 patents forms the final section.

  1. Multiplicity distributions in high-energy neutrino interactions

    Chapman, J.W.; Coffin, C.T.; Diamond, R.N.; French, H.; Louis, W.; Roe, B.P.; Seidl, A.A.; Vander Velde, J.C.; Berge, J.P.; Bogert, D.V.; DiBianca, F.A.; Cundy, D.C.; Dunaitsev, A.; Efremenko, V.; Ermolov, P.; Fowler, W.; Hanft, R.; Harigel, G.; Huson, F.R.; Kolganov, V.; Mukhin, A.; Nezrick, F.A.; Rjabov, Y.; Scott, W.G.; Smart, W.

    1976-01-01

    Results from the Fermilab 15-ft bubble chamber on the charged-particle multiplicity distributions produced in high-energy charged-current neutrino-proton interactions are presented. Comparisons are made to γp, ep, μp, and inclusive pp scattering. The mean hadronic multiplicity appears to depend only on the mass of the excited hadronic state, independent of the mode of excitation. A fit to the neutrino data gives = (1.09+-0.38) +(1.09+-0.03)lnW 2

  2. Multiple-energy Techniques in Industrial Computerized Tomography

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

    1990-08-01

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

  3. New energy carriers in vehicles and their impact on confined infrastructures Overview of previous research and research needs

    Salvi , Olivier; Lonnermark , Anders; Ingason , Haukur; Truchot , Benjamin; Leucker , Roland; Amberg , Félix; Molenaar , Dirk-Jan; Hejny , Horst

    2010-01-01

    International audience; The global warming debate forces the vehicle industry to come up with new environmentally friendly solutions. In 10 years time, or even faster depending on the pressure from different governments in particular in Europe, vehicles will not only use gasoline, diesel and LPG, but also CNG, Hydrogen, ethanol, DME and other bio-fuels, as well as batteries and fuel cells. This quick development and the diversity of new energy carriers can jeopardize the safety in underground...

  4. Understanding the free energy barrier and multiple timescale dynamics of charge separation in organic photovoltaic cells.

    Yan, Yaming; Song, Linze; Shi, Qiang

    2018-02-28

    By employing several lattice model systems, we investigate the free energy barrier and real-time dynamics of charge separation in organic photovoltaic (OPV) cells. It is found that the combined effects of the external electric field, entropy, and charge delocalization reduce the free energy barrier significantly. The dynamic disorder reduces charge carrier delocalization and results in the increased charge separation barrier, while the effect of static disorder is more complicated. Simulation of the real-time dynamics indicates that the free charge generation process involves multiple time scales, including an ultrafast component within hundreds of femtoseconds, an intermediate component related to the relaxation of the hot charge transfer (CT) state, and a slow component on the time scale of tens of picoseconds from the thermally equilibrated CT state. Effects of hot exciton dissociation as well as its dependence on the energy offset between the Frenkel exciton and the CT state are also analyzed. The current results indicate that only a small energy offset between the band gap and the lowest energy CT state is needed to achieve efficient free charge generation in OPV devices, which agrees with recent experimental findings.

  5. Understanding the free energy barrier and multiple timescale dynamics of charge separation in organic photovoltaic cells

    Yan, Yaming; Song, Linze; Shi, Qiang

    2018-02-01

    By employing several lattice model systems, we investigate the free energy barrier and real-time dynamics of charge separation in organic photovoltaic (OPV) cells. It is found that the combined effects of the external electric field, entropy, and charge delocalization reduce the free energy barrier significantly. The dynamic disorder reduces charge carrier delocalization and results in the increased charge separation barrier, while the effect of static disorder is more complicated. Simulation of the real-time dynamics indicates that the free charge generation process involves multiple time scales, including an ultrafast component within hundreds of femtoseconds, an intermediate component related to the relaxation of the hot charge transfer (CT) state, and a slow component on the time scale of tens of picoseconds from the thermally equilibrated CT state. Effects of hot exciton dissociation as well as its dependence on the energy offset between the Frenkel exciton and the CT state are also analyzed. The current results indicate that only a small energy offset between the band gap and the lowest energy CT state is needed to achieve efficient free charge generation in OPV devices, which agrees with recent experimental findings.

  6. Collaboration Mechanism for Equipment Instruction of Multiple Energy Systems

    Wang, Dong; Wang, Tuo; Wang, Qi; Zhang, Zhao; Zhao, Mingyu; Wang, Yinghui

    2018-01-01

    When multiple energy systems execute optimization instructions simultaneously, and the same equipment is Shared, the instruction conflict may occur. Aiming at the above problems, taking into account the control objectives of each system, the characteristics of different systems, such as comprehensive clean energy, energy efficiency, and peak filling, etc., designed the instruction coordination mechanism for the daemon. This mechanism mainly acts on the main station of the system, and form a final optimization instruction. For some specific scenarios, the collaboration mechanism of unlocking the terminal is supplemented. The mechanism determines the specific execution instructions based on the arrival time of the instruction. Finally, the experiment in Tianjin eco-city shows that this algorithm can meet the instruction and collaboration requirements of multi-energy systems, and ensure the safe operation of the equipment.

  7. Rapidity and multiplicity correlations in high energy hadronic collisions

    Heiselberg, H.

    1993-01-01

    Rapidity and multiplicity correlations of particle production in high energy hadronic collisions are studied. A simple model including short range correlations in rapidity due to clustering and long range correlations due to energy conservation is able to describe the two-body correlation functions well hadron-nucleon collisions around lab energies of 250 GeV. In this model fractional moments are calculated and compared to data. The strong rise of the factorial moments in rapidity intervals by size δy∝1 can be explained by long and short range correlation alone whereas the factorial moments approach a constant value at very small δy due to lack of correlations also in agreement with experiment. There is therefore no need for introducing intermittency in the particle production in hadronic collisions at these energies. (orig.)

  8. Smart Energy Management of Multiple Full Cell Powered Applications

    Mohammad S. Alam

    2007-04-23

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

  9. Multiple Jets at the LHC with High Energy Jets

    Andersen, Jeppe Rosenkrantz; Smillie, Jennifer M.

    2011-01-01

    We present a flexible Monte Carlo implementation of the perturbative framework of High Energy Jets, describing multi-jet events at hadron colliders. The description includes a resummation which ensures leading logarithmic accuracy for large invariant mass between jets, and is matched to tree......-level accuracy for multiplicities up to 4 jets. The resummation includes all-order hard corrections, which become important for increasing centre-of-mass energy of the hadronic collision. We discuss observables relevant for confronting the perturbative framework with 7 TeV data from the LHC, and the impact...

  10. Technology data for energy plants. Generation of electricity and district heating, energy storage and energy carrier generation and conversion

    2012-05-15

    The Danish Energy Agency and Energinet.dk, the Danish electricity transmission and system operator, have at regular intervals published a catalogue of energy producing technologies. The previous edition was published in June 2010. This report presents the results of the most recent update. The primary objective of publishing a technology catalogue is to establish a uniform, commonly accepted and up-to-date basis for energy planning activities, such as future outlooks, evaluations of security of supply and environmental impacts, climate change evaluations, and technical and economic analyses, e.g. on the framework conditions for the development and deployment of certain classes of technologies. With this scope in mind, it has not been the intention to establish a comprehensive catalogue, including all main gasification technologies or all types of electric batteries. Only selected, representative, technologies are included, to enable generic comparisons of e.g. thermal gasification versus combustion of biomass and electricity storage in batteries versus hydro-pumped storage. It has finally been the intention to offer the catalogue for the international audience, as a contribution to similar initiatives aiming at forming a public and concerted knowledge base for international analyses and negotiations. A guiding principle for developing the catalogue has been to rely primarily on well-documented and public information, secondarily on invited expert advice. Since many experts are reluctant in estimating future quantitative performance data, the data tables are not complete, in the sense that most data tables show several blank spaces. This approach has been chosen in order to achieve data, which to some extent are equivalently reliable, rather than to risk a largely incoherent data set including unfounded guesstimates. The current update has been developed with an unbalanced focus, i.e. most attention to technologies which are most essential for current and short

  11. Research on an uplink carrier sense multiple access algorithm of large indoor visible light communication networks based on an optical hard core point process.

    Nan, Zhufen; Chi, Xuefen

    2016-12-20

    The IEEE 802.15.7 protocol suggests that it could coordinate the channel access process based on the competitive method of carrier sensing. However, the directionality of light and randomness of diffuse reflection would give rise to a serious imperfect carrier sense (ICS) problem [e.g., hidden node (HN) problem and exposed node (EN) problem], which brings great challenges in realizing the optical carrier sense multiple access (CSMA) mechanism. In this paper, the carrier sense process implemented by diffuse reflection light is modeled as the choice of independent sets. We establish an ICS model with the presence of ENs and HNs for the multi-point to multi-point visible light communication (VLC) uplink communications system. Considering the severe optical ICS problem, an optical hard core point process (OHCPP) is developed, which characterizes the optical CSMA for the indoor VLC uplink communications system. Due to the limited coverage of the transmitted optical signal, in our OHCPP, the ENs within the transmitters' carrier sense region could be retained provided that they could not corrupt the ongoing communications. Moreover, because of the directionality of both light emitting diode (LED) transmitters and receivers, theoretical analysis of the HN problem becomes difficult. In this paper, we derive the closed-form expression for approximating the outage probability and transmission capacity of VLC networks with the presence of HNs and ENs. Simulation results validate the analysis and also show the existence of an optimal physical carrier-sensing threshold that maximizes the transmission capacity for a given emission angle of LED.

  12. Muon energy estimate through multiple scattering with the MACRO detector

    Ambrosio, M; Auriemma, G; Bakari, D; Baldini, A; Barbarino, G C; Barish, B C; Battistoni, G; Becherini, Y; Bellotti, R; Bemporad, C; Bernardini, P; Bilokon, H; Bloise, C; Bower, C; Brigida, M; Bussino, S; Cafagna, F; Calicchio, M; Campana, D; Candela, A; Carboni, M; Caruso, R; Cassese, F; Cecchini, S; Cei, F; Chiarella, V; Choudhary, B C; Coutu, S; Cozzi, M; De Cataldo, G; De Deo, M; Dekhissi, H; De Marzo, C; De Mitri, I; Derkaoui, J; De Vincenzi, M; Di Credico, A; Dincecco, M; Erriquez, O; Favuzzi, C; Forti, C; Fusco, P; Giacomelli, G; Giannini, G; Giglietto, N; Giorgini, M; Grassi, M; Gray, L; Grillo, A; Guarino, F; Gustavino, C; Habig, A; Hanson, K; Heinz, R; Iarocci, E; Katsavounidis, E; Katsavounidis, I; Kearns, E; Kim, H; Kyriazopoulou, S; Lamanna, E; Lane, C; Levin, D S; Lindozzi, M; Lipari, P; Longley, N P; Longo, M J; Loparco, F; Maaroufi, F; Mancarella, G; Mandrioli, G; Margiotta, A; Marini, A; Martello, D; Marzari-Chiesa, A; Mazziotta, M N; Michael, D G; Monacelli, P; Montaruli, T; Monteno, M; Mufson, S; Musser, J; Nicolò, D; Nolty, R; Orth, C; Osteria, G; Palamara, O; Patera, V; Patrizii, L; Pazzi, R; Peck, C W; Perrone, L; Petrera, S; Pistilli, P; Popa, V; Rainó, A; Reynoldson, J; Ronga, F; Rrhioua, A; Satriano, C; Scapparone, E; Scholberg, K; Sciubba, A; Serra, P; Sioli, M; Sirri, G; Sitta, M; Spinelli, P; Spinetti, M; Spurio, M; Steinberg, R; Stone, J L; Sulak, L R; Surdo, A; Tarle, G; Tatananni, E; Togo, V; Vakili, M; Walter, C W; Webb, R

    2002-01-01

    Muon energy measurement represents an important issue for any experiment addressing neutrino-induced up-going muon studies. Since the neutrino oscillation probability depends on the neutrino energy, a measurement of the muon energy adds an important piece of information concerning the neutrino system. We show in this paper how the MACRO limited streamer tube system can be operated in drift mode by using the TDCs included in the QTPs, an electronics designed for magnetic monopole search. An improvement of the space resolution is obtained, through an analysis of the multiple scattering of muon tracks as they pass through our detector. This information can be used further to obtain an estimate of the energy of muons crossing the detector. Here we present the results of two dedicated tests, performed at CERN PS-T9 and SPS-X7 beam lines, to provide a full check of the electronics and to exploit the feasibility of such a multiple scattering analysis. We show that by using a neural network approach, we are able to r...

  13. Charge transport in organic transistors accounting for a wide distribution of carrier energies, Part I : Theory

    Torricelli, F.

    2012-01-01

    An extended theory of carrier hopping transport in organic transistors is proposed. According to many experimental studies, the density of localized states in organic thin-film transistors can be described by a double-exponential function. In this work, using a percolation model of hopping, the

  14. Current and future competitiveness of renewable energy carriers - Conceptions about competitiveness; Foernyelsebara energibaerares nuvarande och framtida konkurrenskraft - foerestaellningar om konkurrenskraft

    Lundgren, K.

    1998-05-01

    The dissertation draws attention to the fact that in the world today 80% of the resources that are used are limited - non renewable energy carriers - and because of the long time between planning and doing (carrying out) within the energy sector, it is worthwhile from the long-term perspective to steer early on towards more sustainable solutions, such as renewable energy carriers. The State and the market have begun to adjust to concepts such as `competitiveness`, which can be viewed as containing both feasibility and legitimacy aspects - the state through different regulations and environmental taxes and environmental fees, and actors on the market that marginally produce/choose renewable energy carriers. The overlying methodology in the dissertation is an actor`s viewpoint. This viewpoint brings forth, in turn, two different views, the analytical and the interpretative. The dissertation presents different stances within the energy sector: commercial production logic, commercial sustainability logic, and the socio-economic sustainability logic. By drawing one`s attention to how one has the possibility to create (enact) his own reality, it is possible to highlight how organisations can increase their competitiveness by being conscious of their own view and others, logic, which in turn forms their views about competitiveness, which in turn determines which projects will materialize. Enterprises and individuals create a description of reality together through a dialectic process, i.e. by developing an environmental management system that contains elements of environmental auditing, environmental performance indicators, and environmental labelling, which `reveal` the production conditions that lie behind the actualization of the final product. An example is the product, `green` electricity, which, in spite of the fact that the final product - electricity - is identical irrespective of the production method, just at the moment can be sold at different prices according

  15. General engineering ethics and multiple stress of atomic energy engineering

    Takeda, Kunihiko

    1999-01-01

    The factors, by which the modern engineering ethics has been profoundly affected, were classified to three categories, namely mental blow, the destruction of human function and environment damage. The role of atomic energy engineering in the ethic field has been shown in the first place. It is pointed out that it has brought about the mental blow by the elucidation of universal truth and discipline and the functional disorder by the power supply. However, the direct effect of radiation to the human kinds is only a part of the stresses comparing to the accumulation of the social stress which should be taken into account of by the possibility of disaster and the suspicion of the atomic energy politics. An increase in the multiple stresses as well as the restriction of criticism will place obstacles on the promotion of atomic energy. (author)

  16. General engineering ethics and multiple stress of atomic energy engineering

    Takeda, Kunihiko [Shibaura Inst. of Tech., Tokyo (Japan)

    1999-08-01

    The factors, by which the modern engineering ethics has been profoundly affected, were classified to three categories, namely mental blow, the destruction of human function and environment damage. The role of atomic energy engineering in the ethic field has been shown in the first place. It is pointed out that it has brought about the mental blow by the elucidation of universal truth and discipline and the functional disorder by the power supply. However, the direct effect of radiation to the human kinds is only a part of the stresses comparing to the accumulation of the social stress which should be taken into account of by the possibility of disaster and the suspicion of the atomic energy politics. An increase in the multiple stresses as well as the restriction of criticism will place obstacles on the promotion of atomic energy. (author)

  17. Modeling and characterization of double resonant tunneling diodes for application as energy selective contacts in hot carrier solar cells

    Jehl, Zacharie; Suchet, Daniel; Julian, Anatole; Bernard, Cyril; Miyashita, Naoya; Gibelli, Francois; Okada, Yoshitaka; Guillemolles, Jean-Francois

    2017-02-01

    Double resonant tunneling barriers are considered for an application as energy selective contacts in hot carrier solar cells. Experimental symmetric and asymmetric double resonant tunneling barriers are realized by molecular beam epitaxy and characterized by temperature dependent current-voltage measurements. The negative differential resistance signal is enhanced for asymmetric heterostructures, and remains unchanged between low- and room-temperatures. Within Tsu-Esaki description of the tunnel current, this observation can be explained by the voltage dependence of the tunnel transmission amplitude, which presents a resonance under finite bias for asymmetric structures. This effect is notably discussed with respect to series resistance. Different parameters related to the electronic transmission of the structure and the influence of these parameters on the current voltage characteristic are investigated, bringing insights on critical processes to optimize in double resonant tunneling barriers applied to hot carrier solar cells.

  18. Multiple scattering in the nuclear rearrangement reactions at medium energy

    Tekou, A.

    1980-09-01

    It is shown that the multiple scattering mechanism is very important in the transfer of the large momenta involved in the nuclear rearrangement reactions at medium energy. In contrast to the usual belief, the reaction cross-section is not very sensitive to the high momenta components of the nuclear wave function. The multiple scattering mechanism is especially important in 4 He(p,d) 3 He reaction around 800 MeV. Here the collisions involving two nucleons of the target nucleus are dominant. The triple collisions contribution is also important. The four collision contribution is negligible in the forward direction and sizeable at large angles. Thus, using the K.M.T. approach in DWBA calculations, the second order term of the optical potential must be included. So, is it not well established that the second term of the K.M.T. optical potential is important for the proton elastic scattering on light nuclei. (author)

  19. Performance, Defect Behavior and Carrier Enhancement in Low Energy, Proton Irradiated p(+)nn(+) InP Solar Cells

    Weinberg, I.; Rybicki, G. C.; Vargas-Aburto, C.; Jain, R. K.; Scheiman, D.

    1994-01-01

    InP p(+)nn(+) cells, processed by MOCVD, were irradiated by 0.2 MeV protons and their performance and defect behavior observed to a maximum fluence of 10(exp 13)/sq cm. Their radiation induced degradation, over this fluence range, was considerably+less than observed for similarly irradiated, diffused junction n p InP cells. Significant degradation occurred in both the cell's emitter and base regions the least degradation occurring in the depletion region. A significant increase in series resistance occurs at the highest fluenc.e. Two majority carrier defect levels, E7 and E10, are observed by DLTS with activation energies at (E(sub C) - 0.39)eV and (E(sub C) - 0.74)eV respectively. The relative concentration of these defects differs considerably from that observed after 1 MeV electron irradiation. An increased carrier concentration in the cell's n-region was observed at the highest proton fluence, the change in carrier concentration being insignificant at the lower fluences. In agreement with previous results, for 1 and 1.5 MeV electron irradiated InP p(+)n junctions, the defect level E10 is attributed to a complex between zinc, diffused into the n-region from the zinc doped emitter, and a radiation induced defect. The latter is assumed to be either a phosphorus vacancy or interstitial. The increased, or enhanced carrier concentration is attributed to this complex acting as a donor.

  20. Assessing District Energy Systems Performance Integrated with Multiple Thermal Energy Storages

    Rezaie, Behnaz

    The goal of this study is to examine various energy resources in district energy (DE) systems and then DE system performance development by means of multiple thermal energy storages (TES) application. This study sheds light on areas not yet investigated precisely in detail. Throughout the research, major components of the heat plant, energy suppliers of the DE systems, and TES characteristics are separately examined; integration of various configurations of the multiple TESs in the DE system is then analysed. In the first part of the study, various sources of energy are compared, in a consistent manner, financially and environmentally. The TES performance is then assessed from various aspects. Then, TES(s) and DE systems with several sources of energy are integrated, and are investigated as a heat process centre. The most efficient configurations of the multiple TESs integrated with the DE system are investigated. Some of the findings of this study are applied on an actual DE system. The outcomes of this study provide insight for researchers and engineers who work in this field, as well as policy makers and project managers who are decision-makers. The accomplishments of the study are original developments TESs and DE systems. As an original development the Enviro-Economic Function, to balance the economic and environmental aspects of energy resources technologies in DE systems, is developed; various configurations of multiple TESs, including series, parallel, and general grid, are developed. The developed related functions are discharge temperature and energy of the TES, and energy and exergy efficiencies of the TES. The TES charging and discharging behavior of TES instantaneously is also investigated to obtain the charging temperature, the maximum charging temperature, the charging energy flow, maximum heat flow capacity, the discharging temperature, the minimum charging temperature, the discharging energy flow, the maximum heat flow capacity, and performance

  1. Distributed EMPC of multiple microgrids for coordinated stochastic energy management

    Kou, Peng; Liang, Deliang; Gao, Lin

    2017-01-01

    Highlights: • Reducing the system wide operating cost compared to the no-cooperation energy management strategy. • Maintaining the supply and demand balance within each microgrid. • Handling the uncertainties in both supply and demand. • Converting the stochastic optimization problems to standard quadratic and linear programming problems. • Achieving a good balance between control performance and computationally feasibility. - Abstract: The concept of multi-microgrids has the potential to improve the reliability and economic performance of a distribution system. To realize this potential, a coordination among multiple microgrids is needed. In this context, this paper presents a new distributed economic model predictive control scheme for the coordinated stochastic energy management of multi-microgrids. By optimally coordinating the operation of individual microgrids, this scheme maintains the system-wide supply and demand balance in an economical manner. Based on the probabilistic forecasts of renewable power generation and microgrid load, this scheme effectively handles the uncertainties in both supply and demand. Using the Chebyshev inequality and the Delta method, the corresponding stochastic optimization problems have been converted to quadratic and linear programs. The proposed scheme is evaluated on a large-scale case that includes ten interconnected microgrids. The results indicated that the proposed scheme successfully reduces the system wide operating cost, achieves the supply-demand balance in each microgrid, and brings the energy exchange between DNO and main grid to a predefined trajectory.

  2. Determination of energy band diagram and charge carrier mobility of white emitting polymer from optical, electrical and impedance spectroscopy

    Mohd Sarjidan, M.A., E-mail: mohd.arif@um.edu.my; Mohd Mokhtar, H.A.; Abd Majid, W.H., E-mail: q3haliza@um.edu.my

    2015-03-15

    A single-layer white polymer light-emitting device (WPLED) has been fabricated using spin coating technique. The device was constructed as ITO/PEDOT:PSS(50 nm)/SPW-111(50 nm)/LiF(1 nm)/Al(100 nm). Indium tin oxide (ITO) and poly(3,4-ethylenedioxythiophene) Polystyrene sulfonate (PEDOT:PSS) are used as the transparent anode. SPW-111 is fabricated as a white emissive layer and lithium fluoride (LiF) and aluminum (Al) are used as reflecting cathode. Energy band diagram of the device was estimated from a combination of ultraviolet–visible (UV–vis) and current–voltage (J–V) analyses. Charge carrier mobility (μ) of PLED was evaluated using negative differential susceptance (−ΔB) method from impedance spectroscopy (IS) analysis. The calculated μ of the SPW-111 device is in the magnitude of 10{sup −6} cm{sup 2}/V/s. - Highlights: • Single layer PLED has been fabricated with spin-coating technique and device performance has been evaluated. • Energy band diagram of the SPW-111 is estimated from optical and electrical analyses. • Charge carrier mobility of the SPW-111 materials is obtained by impedance spectroscopy.

  3. Ultrastructural evaluation of multiple pass low energy versus single pass high energy radio-frequency treatment.

    Kist, David; Burns, A Jay; Sanner, Roth; Counters, Jeff; Zelickson, Brian

    2006-02-01

    The radio-frequency (RF) device is a system capable of volumetric heating of the mid to deep dermis and selective heating of the fibrous septa strands and fascia layer. Clinically, these effects promote dermal collagen production, and tightening of these deep subcutaneous structures. A new technique of using multiple low energy passes has been described which results in lower patient discomfort and fewer side effects. This technique has also been anecdotally described as giving more reproducible and reliable clinical results of tissue tightening and contouring. This study will compare ultrastructural changes in collagen between a single pass high energy versus up to five passes of a multiple pass lower energy treatment. Three subjects were consented and treated in the preauricular region with the RF device using single or multiple passes (three or five) in the same 1.5 cm(2) treatment area with a slight delay between passes to allow tissue cooling. Biopsies from each treatment region and a control biopsy were taken immediately, 24 hours or 6 months post treatment for electron microscopic examination of the 0-1 mm and 1-2 mm levels. Sections of tissue 1 mm x 1 mm x 80 nm were examined with an RCA EMU-4 Transmission Electron Microscope. Twenty sections from 6 blocks from each 1 mm depth were examined by 2 blinded observers. The morphology and degree of collagen change in relation to area examined was compared to the control tissue, and estimated using a quantitative scale. Ultrastructural examination of tissue showed that an increased amount of collagen fibril changes with increasing passes at energies of 97 J (three passes) and 122 J (five passes), respectively. The changes seen after five multiple passes were similar to those detected after much more painful single pass high-energy treatments. This ultrastructural study shows changes in collagen fibril morphology with an increased effect demonstrated at greater depths of the skin with multiple low-fluence passes

  4. Cyclotrons with fast variable and/or multiple energy extraction

    C. Baumgarten

    2013-10-01

    Full Text Available We discuss the possibility in principle of stripping extraction in combination with reverse bends in isochronous separate-sector cyclotrons (and/or fixed field alternating gradient accelerators. If one uses reverse bends between the sectors (instead of or in combination with drifts and places stripper foils at the sector exit edges, the stripped beam has a reduced bending radius and it should be able to leave the cyclotron within the range of the valley—even if the beam is stripped at less than full energy. We are especially interested in stripping of H_{2}^{+}, as it doubles the charge to mass ratio of the ions. However the method could be applied to other ions or ionized molecules as well. For the production of proton beams by stripping extraction of an H_{2}^{+} beam, we discuss possible designs for three types of machines: First, a low-energy cyclotron for the simultaneous production of several beams at multiple energies—for instance 15, 30, and 70 MeV—thus allowing beam delivery on several isotope production targets. In this case it can be an advantage to have a strong energy dependence of the direction of the extracted beam. Second, we consider a fast variable-energy proton machine for cancer therapy that should allow extraction (of the complete beam at all energies in the range of about 70 MeV to about 250 MeV into the same beam line. Third, we consider a high-intensity high-energy machine, where the main design goals are extraction with low losses, low activation of components, and high reliability. Especially if such a machine is considered for an accelerator driven system (ADS, this extraction mechanism has advantages: Beam trips by the failure of electrostatic elements could be avoided and the turn separation would be less critical, which allows operation at lower main cavity voltages. This would in turn reduce the number of rf trips. The price that has to be paid for these advantages is an increase in size and/or field

  5. Cold water for tyre production. Carrier: Intelligent solutions for optimal energy use; Kaltes Wasser fuer heisse Reifen. Carrier: Intelligente Loesungen zur optimalen Energienutzung

    Anon.

    2009-01-15

    Especially when it comes to special solutions for specific applications, this will show how well man and machine are working together. In a production plant of Michelin Reifenwerke at Bad Kreuznach, Carrier installed two absorption refrigerators, in cooperation with further specialist partners. Instead of electric power, the machines utilize waste heat of the production process. (orig.)

  6. Wireless Energy Harvesting Using Signals from Multiple Fading Channels

    Chen, Yunfei

    2017-08-01

    In this paper, we study the average, the probability density function and the cumulative distribution function of the harvested power. In the study, the signals are transmitted from multiple sources. The channels are assumed to be either Rician fading or Gamma-shadowed Rician fading. The received signals are then harvested by using either a single harvester for simultaneous transmissions or multiple harvesters for transmissions at different frequencies, antennas or time slots. Both linear and nonlinear models for the energy harvester at the receiver are examined. Numerical results are presented to show that, when a large amount of harvested power is required, a single harvester or the linear range of a practical nonlinear harvester are more efficient, to avoid power outage. Further, the power transfer strategy can be optimized for fixed total power. Specifically, for Rayleigh fading, the optimal strategy is to put the total power at the source with the best channel condition and switch off all other sources, while for general Rician fading, the optimum magnitudes and phases of the transmitting waveforms depend on the channel parameters.

  7. How High Local Charge Carrier Mobility and an Energy Cascade in a Three-Phase Bulk Heterojunction Enable >90% Quantum Efficiency

    Burke, Timothy M.

    2013-12-27

    Charge generation in champion organic solar cells is highly efficient in spite of low bulk charge-carrier mobilities and short geminate-pair lifetimes. In this work, kinetic Monte Carlo simulations are used to understand efficient charge generation in terms of experimentally measured high local charge-carrier mobilities and energy cascades due to molecular mixing. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. How High Local Charge Carrier Mobility and an Energy Cascade in a Three-Phase Bulk Heterojunction Enable >90% Quantum Efficiency

    Burke, Timothy M.; McGehee, Michael D.

    2013-01-01

    Charge generation in champion organic solar cells is highly efficient in spite of low bulk charge-carrier mobilities and short geminate-pair lifetimes. In this work, kinetic Monte Carlo simulations are used to understand efficient charge generation in terms of experimentally measured high local charge-carrier mobilities and energy cascades due to molecular mixing. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Multiple Timescale Energy Scheduling for Wireless Communication with Energy Harvesting Devices

    H. Xiao

    2012-09-01

    Full Text Available The primary challenge in wireless communication with energy harvesting devices is to efficiently utilize the harvesting energy such that the data packet transmission could be supported. This challenge stems from not only QoS requirement imposed by the wireless communication application, but also the energy harvesting dynamics and the limited battery capacity. Traditional solar predictable energy harvesting models are perturbed by prediction errors, which could deteriorate the energy management algorithms based on this models. To cope with these issues, we first propose in this paper a non-homogenous Markov chain model based on experimental data, which can accurately describe the solar energy harvesting process in contrast to traditional predictable energy models. Due to different timescale between the energy harvesting process and the wireless data transmission process, we propose a general framework of multiple timescale Markov decision process (MMDP model to formulate the joint energy scheduling and transmission control problem under different timescales. We then derive the optimal control policies via a joint dynamic programming and value iteration approach. Extensive simulations are carried out to study the performances of the proposed schemes.

  10. Multiplicity distribution and multiplicity moment of black and grey particles in high energy nucleus–nucleus interactions

    Ghosh, Dipak; Deb, Argha; Datta, Utpal; Bhattacharyya, S.

    2011-01-01

    In this paper we have studied the multiplicity distribution of black and grey particles emitted from 16 O–AgBr interactions at 2.1 AGeV and 60 AGeV. We have also calculated the multiplicity moment up to the fifth order for both the interactions and for both kinds of emitted particles. The variation of multiplicity moment with the order number has been investigated. It is seen that in the case of black particles multiplicity moment up to fourth order remains almost constant as energy increases from 2.1 AGeV to 60 AGeV. Fifth order multiplicity moment increases insignificantly with energy. However in the case of grey particles no such constancy of multiplicity moment with energy of the projectile beam is obtained. Later we have extended our study on the basis of Regge–Mueller approach to find the existence of second order correlation during the emission of black as well as the grey particles. The second Mueller moment is found to be positive and it increases as energy increases in the case of black particles. On the contrary in the case of grey particles the second Mueller moment decreases with energy. It can be concluded that as energy increases correlation among the black particles increases. On the other hand with the increase of energy correlation among the grey particles is found to diminish. (author)

  11. Predictable Particle Engineering: Programming the Energy Level, Carrier Generation, and Conductivity of Core-Shell Particles.

    Yuan, Conghui; Wu, Tong; Mao, Jie; Chen, Ting; Li, Yuntong; Li, Min; Xu, Yiting; Zeng, Birong; Luo, Weiang; Yu, Lingke; Zheng, Gaofeng; Dai, Lizong

    2018-06-20

    Core-shell structures are of particular interest in the development of advanced composite materials as they can efficiently bring different components together at nanoscale. The advantage of this structure greatly relies on the crucial design of both core and shell, thus achieving an intercomponent synergistic effect. In this report, we show that decorating semiconductor nanocrystals with a boronate polymer shell can easily achieve programmable core-shell interactions. Taking ZnO and anatase TiO 2 nanocrystals as inner core examples, the effective core-shell interactions can narrow the band gap of semiconductor nanocrystals, change the HOMO and LUMO levels of boronate polymer shell, and significantly improve the carrier density of core-shell particles. The hole mobility of core-shell particles can be improved by almost 9 orders of magnitude in comparison with net boronate polymer, while the conductivity of core-shell particles is at most 30-fold of nanocrystals. The particle engineering strategy is based on two driving forces: catechol-surface binding and B-N dative bonding and having a high ability to control and predict the shell thickness. Also, this approach is applicable to various inorganic nanoparticles with different components, sizes, and shapes.

  12. Future of the gas industry. Energy carriers instead of power source?

    Bothe, David; Janssen, Matthias; Riechmann, Christoph

    2017-01-01

    For a long time, natural gas was considered as an ideal bridge technology for the energy transition because of the relatively low CO_2 content. With increasing decarbonisation of electricity generation by renewable energies and the associated political vision of a far-reaching electrification of energy applications, in particular in the heat sector, the gas sector is, however, threatened to be overtaken by the renewables. This creates increasing uncertainty for business models and investments in the natural gas sector itself, but also potentially high macroeconomic costs of the energy transition. It can be shown that such a development is not unavoidable if the gas sector succeeds in using the existing possibilities cleverly. Thereby the continued use of existing gas infrastructure plays a central role. For use of the opportunities, however, a paradigm shift in politics, regulation and natural gas sector is necessary, whose key points are developed in this article. [de

  13. Charged Particle, Photon Multiplicity, and Transverse Energy Production in High-Energy Heavy-Ion Collisions

    Raghunath Sahoo

    2015-01-01

    Full Text Available We review the charged particle and photon multiplicities and transverse energy production in heavy-ion collisions starting from few GeV to TeV energies. The experimental results of pseudorapidity distribution of charged particles and photons at different collision energies and centralities are discussed. We also discuss the hypothesis of limiting fragmentation and expansion dynamics using the Landau hydrodynamics and the underlying physics. Meanwhile, we present the estimation of initial energy density multiplied with formation time as a function of different collision energies and centralities. In the end, the transverse energy per charged particle in connection with the chemical freeze-out criteria is discussed. We invoke various models and phenomenological arguments to interpret and characterize the fireball created in heavy-ion collisions. This review overall provides a scope to understand the heavy-ion collision data and a possible formation of a deconfined phase of partons via the global observables like charged particles, photons, and the transverse energy measurement.

  14. Enhancement of energy performance in a boil-off gas re-liquefaction system of LNG carriers using ejectors

    Tan, Hongbo; Zhao, Qingxuan; Sun, Nannan; Li, Yanzhong

    2016-01-01

    Highlights: • An ejector-enhanced LNG boil-off gas (BOG) re-liquefaction system is proposed. • The new system has an improvement of 28% in COP over the existing system. • The specific energy consumption of the new system is reduced to 0.59 kW h/kg(BOG). • The power consumption of 754.1 kW is saved in the case study. - Abstract: An ejector-enhanced Liquefied Natural Gas (LNG) boil-off gas (BOG) re-liquefaction system is proposed to improve the energy efficiency of the existing system. In the new system, two ejectors are respectively used to reduce the energy loss in the expansion of the pressurized BOG and inject a part of fuel BOG into the compression system, and a recuperator is employed to recover the cold energy of the BOG exited from LNG tank. The performance improvement of the proposed system is analysed on the basis of the simulation in Aspen HYSYS. In the case of the re-liquefaction capacity of 4557.6 kg/h, the coefficient of performance (COP) and exergy efficiency can be increased by 28%, and the specific energy consumption (SEC) reduced from 0.756 to 0.59 kW h/kg(BOG) compared to the conventional BOG re-liquefaction system. Correspondingly, the power consumption of 754.1 kW is saved. This means that applying ejectors can effectively improve the energy efficiency of the existing BOG re-liquefaction system for LNG carriers.

  15. Controlling energy transfer between multiple dopants within a single nanoparticle

    DiMaio, Jeffrey R.; Sabatier, Clément; Kokuoz, Baris; Ballato, John

    2008-01-01

    Complex core-shell architectures are implemented within LaF3 nanoparticles to allow for a tailored degree of energy transfer (ET) between different rare earth dopants. By constraining specific dopants to individual shells, their relative distance to one another can be carefully controlled. Core-shell LaF3 nanoparticles doped with Tb3+ and Eu3+ and consisting of up to four layers were synthesized with an outer diameter of ≈10 nm. It is found that by varying the thicknesses of an undoped layer between a Tb3+-doped layer and a Eu3+-doped layer, the degree of ET can be engineered to allow for zero, partial, or total ET from a donor ion to an acceptor ion. More specifically, the ratio of the intensities of the 541-nm Tb3+ and 590 nm Eu3+ peaks was tailored from core-shell configuration that restricts ET is used. Beyond simply controlling ET, which can be limiting when designing materials for optical applications, this approach can be used to obtain truly engineered spectral features from nanoparticles and composites made from them. Further, it allows for a single excitation source to yield multiple discrete emissions from numerous lanthanide dopants that heretofore would have been quenched in a more conventional active optical material. PMID:18250307

  16. High-energy expansion for nuclear multiple scattering

    Wallace, S.J.

    1975-01-01

    The Watson multiple scattering series is expanded to develop the Glauber approximation plus systematic corrections arising from three (1) deviations from eikonal propagation between scatterings, (2) Fermi motion of struck nucleons, and (3) the kinematic transformation which relates the many-body scattering operators of the Watson series to the physical two-body scattering amplitude. Operators which express effects ignored at the outset to obtain the Glauber approximation are subsequently reintroduced via perturbation expansions. Hence a particular set of approximations is developed which renders the sum of the Watson series to the Glauber form in the center of mass system, and an expansion is carried out to find leading order corrections to that summation. Although their physical origins are quite distinct, the eikonal, Fermi motion, and kinematic corrections produce strikingly similar contributions to the scattering amplitude. It is shown that there is substantial cancellation between their effects and hence the Glauber approximation is more accurate than the individual approximations used in its derivation. It is shown that the leading corrections produce effects of order (2kR/subc/) -1 relative to the double scattering term in the uncorrected Glauber amplitude, hk being momentum and R/subc/ the nuclear char []e radius. The leading order corrections are found to be small enough to validate quatitative analyses of experimental data for many intermediate to high energy cases and for scattering angles not limited to the very forward region. In a Gaussian model, the leading corrections to the Glauber amplitude are given as convenient analytic expressions

  17. Hydrogen as Future Energy Carrier: The ENEA Point of View on Technology and Application Prospects

    Marina Ronchetti

    2009-03-01

    Full Text Available Hydrogen and fuel cells should reduce costs and increase reliability and durability to compete in the energy market. A considerable long term effort is necessary for research, development and demonstration of adequate solutions; important programs in this sense are carried out in the main industrialized countries, with the involvement of many industries, research structures and stakeholders. In such framework a relevant role is played in Italy by ENEA (Italian Agency for New Technologies, Energy and Environment. In the paper the main aspects related to the possible hydrogen role in the future society are addressed, according to ENEA perspectives.

  18. Inlfuence of grants and taxes on the final energy costs from selected bioenergy carrier - case study for heat from large scale plants in Germany

    Haerdtlein, M.; Kaltschmitt, M.; Braun, A.

    1996-01-01

    Biogenic fuels represent a promising possibility for the supply of the energy demand and thereby show many advantages. However, there is little use of solid bioenergy carriers in many countries of the EU. Mainly this is caused by the high costs of the provision of energy from organic material compared to the costs of the substitutable fossil energy carriers. Against this background the following paper investigates governmental possibilities to make biomass as a fuel economical competitive for a potential plant operator. For that purpose large scale biomass combustion plants only fired by energy crops are investigated exemplaryly for Germany. Firstly a detailed analysis of the energy provision costs from energy crops is carried out. The results are compared to similar fossil fired plants. Then the influence of governmental guiding instruments for a wider market access of biofuels on the heat production costs will be shown. Finally the results are summarised and the some conclusions are discussed. (Author)

  19. Model-based predictive control applied to multi-carrier energy systems

    Arnold, M.; Negenborn, R.R.; Andersson, G.; De Schutter, B.

    2009-01-01

    The optimal operation of an integrated electricity and natural gas infrastructure is investigated. The couplings between the electricity system and the gas system are modeled by so-called energy hubs, which represent the interface between the loads on the one hand and the transmission

  20. Wood as a raw commodity and energy carrier; Holz als Rohstoff und Energietraeger. Dynamisches Holzmarktmodell und Zukunftsszenarien - Schlussbericht

    Pauli, B.; Buergi, P.; Bruehlhard, S. [Schweizerische Hochschule fuer Landwirtschaft, Zollikofen (Switzerland); Thees, O.; Lemm, R.; Rosset, Ch. [Eidg. Forschungsanstalt fuer Wald, Schnee und Landschaft, WSL, Birmensdorf (Switzerland)

    2010-05-15

    This comprehensive final report for the Swiss Federal Office of Energy (SFOE) takes a look at a dynamic wood-market model and the future prospects for the use of wood as a raw commodity and energy carrier. As an introduction, an overview of Swiss and international wood markets is provided. Various sorts of timber - from whole tree-trunks to waste wood for use as an energy source - are discussed. The international wood market is looked at and future developments are discussed. The report goes on to deal with four project stages which help provide an information basis in order to be able to review the current situation and the future developments in the Swiss wood industry. The first stage of the project involved the elaboration of a material-flow matrix for the year 2005. The sources of the data are discussed. Inconsistencies in the data are looked at and the Swiss wood market is analysed. This material-flow matrix provided the basis for a second step, the development of a product-oriented, dynamic wood market model. Here, all sources of wood from forests to waste wood are looked at and their use for building and as an energy resource is considered. Model development, variants and modelling factors are discussed. An expert-aided model is looked at. The market models developed were used for the third step, the development of scenarios for future development. Five scenarios were developed, including higher energy costs, a large, heavy storm event, increased per capita wood use, increasing global timber prices as well as the installation of a new, large-scale sawmill. In a final step, based on knowledge gained from the previous steps, suggestions for further action to be taken by politics were elaborated. Here, measures that would have an effect on supply and demand are suggested that could help decrease the costs for the harvesting of wood resources and support changes in the market behaviour of forest owners.

  1. Assessing the Multiple Benefits of Clean Energy Full Report

    Guidance for state energy, environmental, and economic policy makers to identify and quantify the many benefits of clean energy to support the development and implementation of cost-effective clean energy initiatives.

  2. Cascade multiplicity inside deuteron in Π d high energy collisions

    Kisielewska, D.

    1983-01-01

    Multiplicity distribution of double scattering events is analysed using the additive quark model including the cascading effect. The mean multiplicity of particles produced in the process of cascading estimated for Π d experiments at 100, 205 and 360 GeV/c is equal to 1.15 ± .31. This value does not depend on the momentum of the incident pion. Some indications are found that the probability of cascading depends on multiplicity of the collision with the first nucleon and is smaller for low multiplicities. (author)

  3. The impact of large-scale energy storage requirements on the choice between electricity and hydrogen as the major energy carrier in a non-fossil renewables-only scenario

    Converse, Alvin O.

    2006-01-01

    The need for large-scale storage, when the energy source is subject to periods of low-energy generation, as it would be in a direct solar or wind energy system, could be the factor which justifies the choice of hydrogen, rather than electricity, as the principal energy carrier. It could also be the 'Achilles heel' of a solar-based sustainable energy system, tipping the choice to a nuclear breeder system

  4. Charcoal as an alternative energy carrier. Pt. 2: Conversion of biomass

    Holstad, A

    1978-12-01

    Terrestrial biomass, residues from forestry, agriculture and farming can be converted by biochemical or thermochemical techniques to fuels. The charcoal yield depends on the raw materials, moisture contents, the temperature of carbonisation and the processing equipment. The yield is reduced by 2 - 3% when using softwood and furthermore with higher temperature of carbonisation. Generally charcoal contains 80 - 90% carbon, 0,5 - 10% ash and 7 - 30% volatile matter. Theoretically the following products are obtained when pyrolising wood: 34,7% Charcoal, 24,9% H/sub 2/O, 10,9% CO/sub 2/, 4,15 CO, 1,6% Methanol, 5,9% Acetic Acid and 17,9% Tar. Units for production of charcoal are large and small kilns, transportable Thomas retorts and Cornell retorts with a production of 1,3 - 6 tons charcoal/day, and the large Lambiotte retort, multiple-hearth furnaces and fluidized-bed reactors. Interesting is also the new equipment of Skogens Kol in Sweden. These large units have a production capacity of 16 - 80 tons charcoal/day. Important production parameters include charcoal yield, labour requirements, air pollution and cost. Based on these parameters the Cornell retort is considered the best unit for production of small quantities of charcoal and Skogens Kol seems to be the most interesting large unit. 17 drawings, 14 tables.

  5. Coral mucus functions as an energy carrier and particle trap in the reef ecosystem

    Wild, C.; Huettel, M.; Klueter, A.

    2004-01-01

    Zooxanthellae, endosymbiotic algae of reef-building corals, substantially contribute to the high gross primary production of coral reefs(1), but corals exude up to half of the carbon assimilated by their zooxanthellae as mucus(2,3). Here we show that released coral mucus efficiently traps organic...... matter from the water column and rapidly carries energy and nutrients to the reef lagoon sediment, which acts as a biocatalytic mineralizing filter. In the Great Barrier Reef, the dominant genus of hard corals, Acropora, exudes up to 4.8 litres of mucus per square metre of reef area per day. Between 56......% and 80% of this mucus dissolves in the reef water, which is filtered through the lagoon sands. Here, coral mucus is degraded at a turnover rate of at least 7% per hour. Detached undissolved mucus traps suspended particles, increasing its initial organic carbon and nitrogen content by three orders...

  6. Spreading The Net: The Multiple Benefits Of Energy Efficiency Improvements

    NONE

    2012-07-01

    Improving energy efficiency can deliver a range of benefits to the economy and society. However energy efficiency programmes are often evaluated only on the basis of the energy savings they deliver. As a result, the full value of energy efficiency improvements in both national and global economies may be significantly underestimated. This also means that energy efficiency policy may not be optimised to target the potential of the full range of outcomes possible. Moreover, when the merit of energy efficiency programmes is judged solely on reductions in energy demand, programmes are susceptible to criticisms related to the rebound effect when the energy savings are less than expected due to other welfare gains. There are several reasons why the full range of outcomes from energy efficiency policy is not generally evaluated. First, it is due to the non-market, somewhat intangible, nature of the socioeconomic benefits, which makes them difficult to quantify. Second, the effects due to energy efficiency alone can be complex to isolate and to determine causality. Third, evaluators and policy makers working in the energy efficiency sphere are usually energy professionals, working for an energy agency or ministry, with little experience of how energy efficiency might impact other non-energy sectors. The result is an under-appreciation – and related underinvestment – in energy efficiency, and as a consequence, missed opportunities and benefits. These foregone benefits represent the ‘opportunity cost’ of failing to adequately evaluate and prioritize energy efficiency investments. The objective of this report is to fully outline the array of different benefits from improved energy efficiency and investigate their implications for policy design. By better understanding the different benefits arising from energy efficiency it should be easier for policy makers to prioritise the most significant outcomes, in addition to energy savings, in optimising energy efficiency

  7. DGEMP/CGP energy policy lecture cycle - technical and economical stakes of hydrogen as an energy carrier

    Alleau, T.; Freund, E.; Coiffard, J.

    2002-01-01

    Hydrogen is attracting a lot a interest from energy specialists, in particular because supply safety issues are back on the agendas. One of the most promising applications seems to be the 'combustible cells', which changes hydrogen into electricity and heat in various applications: 'mobile', as an alternative to electric cells, for instance in telephones or lap-top computers, 'stationary' for producing electricity and heat, including small and medium voltage, and 'transport' with a high number of light vehicle and even bus prototypes. (authors)

  8. Wireless Energy Harvesting Using Signals from Multiple Fading Channels

    Chen, Yunfei; Zhao, Nan; Alouini, Mohamed-Slim

    2017-01-01

    fading or Gamma-shadowed Rician fading. The received signals are then harvested by using either a single harvester for simultaneous transmissions or multiple harvesters for transmissions at different frequencies, antennas or time slots. Both linear

  9. Efficient charge carrier injection into sub-250 nm AlGaN multiple quantum well light emitting diodes

    Mehnke, Frank, E-mail: mehnke@physik.tu-berlin.de; Kuhn, Christian; Guttmann, Martin; Reich, Christoph; Kolbe, Tim; Rass, Jens; Wernicke, Tim [Technische Universität Berlin, Institut für Festkörperphysik, Hardenbergstr. 36, EW 6-1, 10623 Berlin (Germany); Kueller, Viola; Knauer, Arne; Lapeyrade, Mickael; Einfeldt, Sven; Weyers, Markus [Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin (Germany); Kneissl, Michael [Technische Universität Berlin, Institut für Festkörperphysik, Hardenbergstr. 36, EW 6-1, 10623 Berlin (Germany); Ferdinand-Braun-Institut, Leibniz-Institut für Höchstfrequenztechnik, Gustav-Kirchhoff-Str. 4, 12489 Berlin (Germany)

    2014-08-04

    The design and Mg-doping profile of AlN/Al{sub 0.7}Ga{sub 0.3}N electron blocking heterostructures (EBH) for AlGaN multiple quantum well (MQW) light emitting diodes (LEDs) emitting below 250 nm was investigated. By inserting an AlN electron blocking layer (EBL) into the EBH, we were able to increase the quantum well emission power and significantly reduce long wavelength parasitic luminescence. Furthermore, electron leakage was suppressed by optimizing the thickness of the AlN EBL while still maintaining sufficient hole injection. Ultraviolet (UV)-C LEDs with very low parasitic luminescence (7% of total emission power) and external quantum efficiencies of 0.19% at 246 nm have been realized. This concept was applied to AlGaN MQW LEDs emitting between 235 nm and 263 nm with external quantum efficiencies ranging from 0.002% to 0.93%. After processing, we were able to demonstrate an UV-C LED emitting at 234 nm with 14.5 μW integrated optical output power and an external quantum efficiency of 0.012% at 18.2 A/cm{sup 2}.

  10. Efficient charge carrier injection into sub-250 nm AlGaN multiple quantum well light emitting diodes

    Mehnke, Frank; Kuhn, Christian; Guttmann, Martin; Reich, Christoph; Kolbe, Tim; Rass, Jens; Wernicke, Tim; Kueller, Viola; Knauer, Arne; Lapeyrade, Mickael; Einfeldt, Sven; Weyers, Markus; Kneissl, Michael

    2014-01-01

    The design and Mg-doping profile of AlN/Al 0.7 Ga 0.3 N electron blocking heterostructures (EBH) for AlGaN multiple quantum well (MQW) light emitting diodes (LEDs) emitting below 250 nm was investigated. By inserting an AlN electron blocking layer (EBL) into the EBH, we were able to increase the quantum well emission power and significantly reduce long wavelength parasitic luminescence. Furthermore, electron leakage was suppressed by optimizing the thickness of the AlN EBL while still maintaining sufficient hole injection. Ultraviolet (UV)-C LEDs with very low parasitic luminescence (7% of total emission power) and external quantum efficiencies of 0.19% at 246 nm have been realized. This concept was applied to AlGaN MQW LEDs emitting between 235 nm and 263 nm with external quantum efficiencies ranging from 0.002% to 0.93%. After processing, we were able to demonstrate an UV-C LED emitting at 234 nm with 14.5 μW integrated optical output power and an external quantum efficiency of 0.012% at 18.2 A/cm 2

  11. ALGORITHM TO CHOOSE ENERGY GENERATION MULTIPLE ROLE STATION

    Alexandru STĂNESCU

    2014-05-01

    Full Text Available This paper proposes an algorithm that is based on a complex analysis method that is used for choosing the configuration of a power station. The station generates electric energy and hydrogen, and serves a "green" highway. The elements that need to be considered are: energy efficiency, location, availability of primary energy sources in the area, investment cost, workforce, environmental impact, compatibility with existing systems, meantime between failure.

  12. A new perspective on anisotropy and multiple energy gaps in superconductors

    Milkove, K.R.; Bostock, J.; MacVicar, M.L.A.

    1976-01-01

    New perspective on superconducting anisotropy and multiple energy gaps: direct experimental evidence shows that widely accepted anisotropy and multiple energy gap interpretations of tunneling data are consistent with a voltage divider model and may not relate to intrinsic superconducting properties. The model also accounts for other common data anomalies. (author)

  13. Synthesis, performance and regeneration of carbon membranes for biogas upgrading - a future energy carrier

    Lie, Jon Arvid

    2005-07-01

    was also seen on the surface of Ag-nitrate containing carbon. However, the Ag- and Cu-containing membranes showed a high H2 permeability. Adding metal oxides makes the carbon membranes retard the transport of easily condensable gases (e.g. CO2). This can be exploited for enhanced H2/CO{sub 2} separation efficiency. A simple, energy effective and rapid regeneration method for membranes that are conductors or semi-conductors has been developed: When a low voltage, direct current was applied on an iron-doped carbon, sorption of gases in the carbon decreased, while diffusivity increased to a larger degree, resulting in enhanced permeation rates. Electrothermal regeneration may also be applied online, and is especially suitable for separation in non-oxidizing atmospheres, like CO{sub 2}/CH{sub 4} separation. The method can be used for a continuous process, and not only for batchwise regeneration (e.g. activated carbon). The CO{sub 2} permeability increased with about 60%, while the CH{sub 4} permeability was unchanged (single gas tests). Mixed gas tests on the same type of iron-doped carbon (without current applied) resulted in a reduction of both the CO2 permeability and the selectivity, compared to single gas tests. High performance carbon membranes were also formed from the commercial polymer XP (cover name). The CO{sub 2}/CH{sub 4} selectivity was typically larger than 100, with a CO2 permeability of about 200 Barrer (single gas tests). The applied precursor film thickness was in the range 50-70 micron, and was found to be crucial for the carbonization process. Films of 100 microns or more resulted in cracks during carbonization, probably because of low gas drainage, and were rendered useless. Carbon membranes from XP possess two important advantages: 1) The films produced at 500 C have some degree of flexibility, hence easy to handle and process. Masking and testing these carbons were not challenging, when a proper precursor film thickness was used. 2) Aging seems not

  14. Free energy from molecular dynamics with multiple constraints

    den Otter, Wouter K.; Briels, Willem J.

    2000-01-01

    In molecular dynamics simulations of reacting systems, the key step to determining the equilibrium constant and the reaction rate is the calculation of the free energy as a function of the reaction coordinate. Intuitively the derivative of the free energy is equal to the average force needed to

  15. The Multiple Benefits of Measures to Improve Energy Efficiency

    Puig, Daniel; Farrell, Timothy Clifford

    Understanding the barriers to, and enablers for, energy efficiency requires targeted information and analysis. This report is a summary of four detailed studies providing new insights on how to promote efficiency in selected priority areas. It complements initiatives such as the so-called energy...... efficiency accelerators, which seek to increase the uptake of selected technologies, as well as the work of many other institutions committed to improving energy efficiency. The modelling estimates and the case studies presented in this report illustrate that, while significant progress has already been...... achieved, the case for accelerating energy efficiency action is strong. Key highlights include: • At the global level, energy efficiency improvements would account for between 2.6 and 3.3 Gt CO2e of the reductions in 2030, equivalent to between 23 and 26 percent of the overall reductions achieved...

  16. Operation of multiple superconducting energy doubler magnets in series

    Kalbfleisch, G.; Limon, P.J.; Rode, C.

    1977-01-01

    In order to understand the operational characteristics of the Energy Doubler, a series of experiments were begun which were designed to be a practical test of running superconducting accelerator magnets in series. Two separate tests in which two Energy Doubler dipoles were powered in series are described. Of particular interest are the static losses of the cryostats and the behavior of the coils and cryostats during quenches. The results of the tests show that Energy Doubler magnets can be safely operated near their short sample limit, and that the various safety devices used are adequate to protect the coils and the cryostats from damage

  17. Graphical analysis of processes with multiple activation energies

    Lachter, J.; Bragg, R.H.; Close, E.

    1986-01-01

    The activation energies characterizing a kinetic process are derived from the slopes of the Arrhenius diagrams obtained by plotting rate constants versus reciprocal temperature. Those rate constants correspond to the shifts along the time axis needed to superpose the successive isotherms. A general method based on Chebyshev interpolation is proposed for the optimization of the superposition of the experimental data points. This method is applied to determine the activation energies of the graphitization kinetics of the interlayer spacings of pitch coke and pyrocarbon samples

  18. Scaling of chaotic multiplicity: A new observation in high-energy interactions

    Ghosh, D.; Ghosh, P.; Roy, J.

    1990-01-01

    We analyze high-energy-interaction data to study the dependence of chaotic multiplicity on the pseudorapidity window and propose a new scaling function bar Ψ(bar z)=left-angle n 1 right-angle/left-angle n right-angle max where left-angle n 1 right-angle is the chaotic multiplicity and bar z=left-angle n right-angle/left-angle n right-angle max is the reduced multiplicity, following the quantum-optical concept of particle production. It has been observed that the proposed ''chaotic multiplicity scaling'' is obeyed by pp, p bar p, and AA collisions at different available energies

  19. Uncovering the multiple objectives behind national energy efficiency planning

    Haydt, Gustavo; Leal, Vítor; Dias, Luís

    2013-01-01

    This work seeks to identify the fundamental objectives behind the development of energy efficiency (EE) plans for countries. It also presents a method to quantify the degree of achievement of each objective, through the identification and operationalization of attributes. This was achieved by applying Keeney's value-focused thinking approach. For that purpose, three key decision makers in EE planning were interviewed along with a bibliographic review on the subject. From this process six fundamental objectives were identified formalizing the problem as a multi-objective one: (i) to minimize the influence of energy use on climate change; (ii) to minimize the financial risk from the investment; (iii) to maximize the security of energy supply; (iv) to minimize investment costs; (v) to minimize the impacts of building new power plants and transmission infrastructures and (vi) to maximize the local air quality. The respective attributes were: (i) CO 2 emissions savings; (ii) payback; (iii) imported energy savings; (iv) investment cost; (v) electricity savings; and (vi) total suspended particles savings. To show the usefulness of the work, the objectives and attributes identified were used to show the possible outcomes from five hypothetical EE plans for Portugal

  20. Multiple exchange and high-energy fixed-angle scattering

    Halliday, I G; Orzalesi, C A; Tau, M

    1975-01-01

    The application of the eikonal ansatz to fermion fermion elastic scattering with Abelian vector gluon exchanges is discussed. The behaviours of the elastic scattering amplitude and the elastic form factor are considered and an important mechanism for fixed angle high energy elastic scattering is identified. (6 refs).

  1. Multiple vacancy production by high energy heavy ions

    Becker, R.L.; Ford, A.L.; Reading, J.F.

    1984-01-01

    The theory of atomic collisions has two ingredients: collision theory and atomic structure theory. The collision theories differ with respect to (A) the collision dynamics and (B) the treatment of the relative motion of the projectile and target nuclei. With regard to the dynamics multiple vacancy production is of fundamental interest because it is a signature for and probe of strong interactions between the projectile and the target electrons. For projectiles of large nuclear charge, Z/sub p/, especially for those which are highly stripped so as to have a large ionic charge, q, the interaction becomes strong enough to give a high probability of multiple vacancy production and a breakdown of perturbation theory. The familiar first and second Born approximations and their off-shoots cease to be adequate. Not even the recent strong-potential Born approximation (see Taulbjerg 1984) is sufficient, because the weaker of the potentials generated by the projectile and the target nuclei, respectively, is treated in first order. One needs a unitary, non-perturbative collision theory. At present this is generally available for multiple vacancy production only in the form of the highly numerical coupled channels theory (Becker et al. 1983, 1984b). For special problems analytically tractable models have been devised. For example, a simple, unitary, geometrical encounter probability model for the calculation of p/sub L/(0), the inclusive L-shell vacancy probability per electron in collisions with impact parameter B = 0, has been introduced by Sulik et al. (1984) and further developed by Sulik and Hock (1984). Along with earlier coupled-channels calculations (Becker et al. 1984ab) and first Magnus calculations (Becker et al. 1984b), this model is able to describe the saturation of p/sub L/(0) with Z/sub p/ at fixed impact speed, v, whereas all the first-order theories predict p/sub L/ proportional to Z/sub p/ 2 , which eventually exceeds unity

  2. Simulation of energy use in buildings with multiple micro generators

    Karmacharya, S.; Putrus, G.; Underwood, C.P.; Mahkamov, K.; McDonald, S.; Alexakis, A.

    2014-01-01

    This paper focuses on the detailed modelling of micro combined heat and power (mCHP) modules and their interaction with other renewable micro generators in domestic applications based on an integrated modular modelling approach. The simulation model has been developed using Matlab/Simulink and incorporates a Stirling engine mCHP module embedded in a lumped-parameter domestic energy model, together with contributions from micro wind and photovoltaic modules. The Stirling cycle component model is based on experimental identification of a domestic-scale system which includes start up and shut down characteristics. The integrated model is used to explore the interactions between the various energy supply technologies and results are presented showing the most favourable operating conditions that can be used to inform the design of advanced energy control strategies in building. The integrated model offers an improvement on previous models of this kind in that a fully-dynamic approach is adopted for the equipment and plant enabling fast changing load events such as switching on/off domestic loads and hot water, to be accurately captured at a minimum interval of 1 min. The model is applied to two typical 3- and 4-bedroom UK house types equipped with a mCHP module and two other renewable energy technologies for a whole year. Results of the two cases show that the electrical contribution of a Stirling engine type mCHP heavily depends on the thermal demand of the building and that up to 19% of the locally-generated electricity is exported whilst meeting a similar percentage of the overall annual electricity demand. Results also show that the increased number of switching of mCHP module has an impact on seasonal module efficiency and overall fuel utilisation. The results demonstrate the need for the analysis of equipment design and optimal sizing of thermal and electrical energy storage. -- Highlights: • Dynamic modelling of a building along with its space heating and hot

  3. Directional phonon-assisted cascading of photoexcited carriers in stepped Inx(Al0.17Ga0.83)1-xAs/Al0.17Ga0.83As multiple quantum wells

    Machida, S.; Matsuo, M.; Fujiwara, K.

    2002-01-01

    Perpendicular motion of photoexcited electron and hole pairs assisted by phononscattering is investigated in a novel step-graded staircase heterostructure consisting of strained In-1(Al0.17Ga0.83)(1-x). As multiple quantum wells (QWs) with similar widths but five different x values by cw and time...... amplitude in the inter-mediate temperature range, These variations reveal that the photoexcited carriers directionally move from shallower to deeper QWs via phonon-assisted activation above the barrier hand edge state. The PL dynamics directly indicate the perpendicular flowing of photoexcited carriers...

  4. Electromagnetic energy harvesting from vibrations of multiple frequencies

    Yang Bin; Lee Chengkuo; Xie Jin; Han He, Johnny; Kotlanka, Rama Krishna; Feng Hanhua; Xiang Wenfeng; Low, Siew Ping

    2009-01-01

    A novel multi-frequency energy harvester has been designed and fabricated, which consists of three permanent magnets, three sets of two-layer copper coils and a supported beam of acrylic, while these coils are made of thin fire resistant 4 (FR4) substrates using a standard printed circuit board. The energy under the first, second and third resonant modes can be harvested, corresponding to the resonant frequencies of 369 Hz, 938 Hz and 1184 Hz, respectively. The maximum output voltage and power of the first and second vibration modes are 1.38 mV, 0.6 µW and 3.2 mV, 3.2 µW for a 14 µm exciting vibration amplitude and a 0.4 mm gap between the magnet and coils, respectively. The feasibility study results are in good agreement with the theoretical calculations and show promising application potentials

  5. Energy Management of an Off-Grid Hybrid Power Plant with Multiple Energy Storage Systems

    Laura Tribioli

    2016-08-01

    Full Text Available In this paper, an off-grid hybrid power plant with multiple storage systems for an artificial island is designed and two possible strategies for the management of the stored energy are proposed. Renewable power sources (wind/solar technologies are used as primary power suppliers. A lead-acid battery pack (BAT and a reversible polymer electrolyte fuel cell are employed to fulfill the power demand and to absorb extra power. The reversible fuel cell allows reducing costs and occupied space and the fuel cell can be fed by the pure hydrogen produced by means of its reversible operation as an electrolyzer. A diesel engine is employed as backup system. While HOMER Pro® has been employed for a full-factorial-based optimization of the sizes of the renewable sources and the BAT, Matlab/Simulink® has been later used for simulating the plant operation and compare two possible power management control strategies. For the reversible fuel cell sizing, a sensitivity analysis has been carried out varying stack and hydrogen tank sizes. The final choice for plant configuration and power management control strategy has been made on the basis of a comparative analysis of the results, aimed at minimizing fossil fuel consumption and CO2 emissions, battery aging rate and at maximizing the power plant overall efficiency. The obtained results demonstrate the possibility of realizing a renewable power plant, able to match the needs of electrical power in a remote area, by achieving a good integration of different energy sources and facing the intermittent nature of renewable power sources, with very low use of fossil fuels.

  6. Auger heating of carriers in {GaAs}/{AlAs} heterostructures

    Borri, P.; Ceccherini, S.; Gurioli, M.; Bogani, F.

    1997-07-01

    The photoluminescence of {GaAs}/{AlAs} multiple quantum wells structures under optical ps excitation is investigated for carrier densities in the range 10 18-4 × 10 19 cm -3 with frequency and time-resolved spectroscopic techniques. The measurements give a direct evidence of the occurrence in the sample of carrier heating. This energy up-conversion gives rise to photoluminescence from the states near the Fermi level whose intensity and time evolution depend on the carrier density in a strongly non-linear way. The observed behaviour can be explained introducing in the carrier dynamics an up-conversion mechanism due to Auger-like processes.

  7. Even-odd charged multiplicity distributions and energy dependence of normalized multiplicity moments in different rapidity windows

    Wu Yuanfang; Liu Lianshou

    1990-01-01

    The even and odd multiplicity distributions for hadron-hadron collision in different rapidity windows are calculated, starting from a simple picture for charge correlation with non-zero correlation length. The coincidence and separation of these distributions are explained. The calculated window-and energy-dependence of normalized moments recovered the behaviour found in experiments. A new definition for normalized moments is propossed, especially suitable for narrow rapidity windows

  8. Characterization of Charge-Carrier Transport in Semicrystalline Polymers: Electronic Couplings, Site Energies, and Charge-Carrier Dynamics in Poly(bithiophene- alt -thienothiophene) [PBTTT

    Poelking, Carl

    2013-01-31

    We establish a link between the microscopic ordering and the charge-transport parameters for a highly crystalline polymeric organic semiconductor, poly(2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene) (PBTTT). We find that the nematic and dynamic order parameters of the conjugated backbones, as well as their separation, evolve linearly with temperature, while the side-chain dynamic order parameter and backbone paracrystallinity change abruptly upon the (also experimentally observed) melting of the side chains around 400 K. The distribution of site energies follows the behavior of the backbone paracrystallinity and can be treated as static on the time scale of a single-charge transfer reaction. On the contrary, the electronic couplings between adjacent backbones are insensitive to side-chain melting and vary on a much faster time scale. The hole mobility, calculated after time-averaging of the electronic couplings, reproduces well the value measured in a short-channel thin-film transistor. The results underline that to secure efficient charge transport in lamellar arrangements of conjugated polymers: (i) the electronic couplings should present high average values and fast dynamics, and (ii) the energetic disorder (paracrystallinity) should be small. © 2013 American Chemical Society.

  9. Characterization of Charge-Carrier Transport in Semicrystalline Polymers: Electronic Couplings, Site Energies, and Charge-Carrier Dynamics in Poly(bithiophene- alt -thienothiophene) [PBTTT

    Poelking, Carl; Cho, Eunkyung; Malafeev, Alexander; Ivanov, Viktor; Kremer, Kurt; Risko, Chad; Bré das, Jean-Luc; Andrienko, Denis

    2013-01-01

    We establish a link between the microscopic ordering and the charge-transport parameters for a highly crystalline polymeric organic semiconductor, poly(2,5-bis(3-tetradecylthiophen-2-yl)thieno[3,2-b]thiophene) (PBTTT). We find that the nematic and dynamic order parameters of the conjugated backbones, as well as their separation, evolve linearly with temperature, while the side-chain dynamic order parameter and backbone paracrystallinity change abruptly upon the (also experimentally observed) melting of the side chains around 400 K. The distribution of site energies follows the behavior of the backbone paracrystallinity and can be treated as static on the time scale of a single-charge transfer reaction. On the contrary, the electronic couplings between adjacent backbones are insensitive to side-chain melting and vary on a much faster time scale. The hole mobility, calculated after time-averaging of the electronic couplings, reproduces well the value measured in a short-channel thin-film transistor. The results underline that to secure efficient charge transport in lamellar arrangements of conjugated polymers: (i) the electronic couplings should present high average values and fast dynamics, and (ii) the energetic disorder (paracrystallinity) should be small. © 2013 American Chemical Society.

  10. Energy efficient design for MIMO two-way AF multiple relay networks

    Alsharoa, Ahmad M.; Ghazzai, Hakim; Alouini, Mohamed-Slim

    2014-01-01

    This paper studies the energy efficient transmission and the power allocation problem for multiple two-way relay networks equipped with multi-input multi-output antennas where each relay employs an amplify-and-forward strategy. The goal

  11. Incorporating Multiple Energy Relay Dyes in Liquid Dye-Sensitized Solar Cells

    Yum, Jun-Ho; Hardin, Brian E.; Hoke, Eric T.; Baranoff, Etienne; Zakeeruddin, Shaik M.; Nazeeruddin, Mohammad K.; Torres, Tomas; McGehee, Michael D.; Grä tzel, Michael

    2011-01-01

    Panchromatic response is essential to increase the light-harvesting efficiency in solar conversion systems. Herein we show increased light harvesting from using multiple energy relay dyes inside dye-sensitized solar cells. Additional photoresponse

  12. Proton multiplicity distributions in high-energy hadron-nuclei collisions

    Strugalski, Z.

    1979-01-01

    The fast proton emission process is analyzed in high-energy hadron-nuclei collisions. The formula describing the proton multiplicity distributions is derived. It describes well enough the proton multiplicity distribution of pion-nuclei and proton-nuclei collisions at 200 and 400 GeV

  13. Risk of Japanese carriers of hyperphosphorylated paratarg-7, the first autosomal-dominantly inherited risk factor for hematological neoplasms, to develop monoclonal gammopathy of undetermined significance and multiple myeloma.

    Grass, Sandra; Iida, Shinsuke; Wikowicz, Aleksandra; Preuss, Klaus-Dieter; Inagaki, Atsushi; Shimizu, Kazuyuki; Ziepert, Marita; Ueda, Ryuzo; Pfreundschuh, Michael

    2011-03-01

    Hyperphosphorylated paratarg-7 (pP-7) is a frequent target of paraproteins in German patients with monoclonal gammopathy of undetermined significance (MGUS)/multiple myeloma (MM). The frequency of MGUS/MM is lower in Japan than in Europe. As pP-7, the first molecularly defined autosomal-dominant risk factor for any hematological neoplasm, is inherited in a dominant fashion, we determined the incidence of the pP-7 carrier state in a Japanese population, and compared the frequency of pP-7-specific paraproteins and the pP-7 carrier state in Japanese and German patients with MGUS/MM. Peripheral blood from 111 Japanese patients with MGUS/MM and 278 healthy blood donors was analyzed for the pP-7 carrier state by isoelectric focusing and for pP-7-specific antibodies by ELISA. The Japanese group was compared with 252 German MGUS/MM patients and 200 healthy controls. Five of 111 (4.5%) Japanese and 35/252 (13.9%) German IgA/IgG MGUS/MM patients had a pP-7-specific paraprotein (P=0.009). The prevalence of healthy pP-7 carriers in the Japanese study group was 1/278 (0.36%), whereas it was 4/200 in the German group (P=0.166). The relative risk for pP-7 carriers developing MGUS/MM had an odds ratio of 13.1 in the Japanese and 7.9 in the German group. In conclusion, the fraction of pP-7 carriers with a pP-7-specific paraprotein is lower among Japanese than in German patients with MGUS/MM, but pP-7 carriers in both ethnic groups have a high risk of developing MGUS/MM. © 2011 Japanese Cancer Association.

  14. Radionuclide carrier

    Hartman, F.A.; Kretschmar, H.C.; Tofe, A.J.

    1978-01-01

    A physiologically acceptable particulate radionuclide carrier is described. It comprises a modified anionic starch derivative with 0.1% to 1.5% by weight of a reducing agent and 1 to 20% by weight of anionic substituents

  15. Carrier Screening

    ... How accurate is carrier screening? No test is perfect. In a small number of cases, test results ... in which an egg is removed from a woman’s ovary, fertilized in a laboratory with the man’s ...

  16. Centrality dependence of multiplicity, transverse energy, and elliptic flow from hydrodynamics

    Kolb, Peter F.; Heinz, Ulrich; Huovinen, Pasi; Eskola, Kari J.; Tuominen, Kimmo

    2001-03-21

    The centrality dependence of the charged multiplicity, transverse energy, and elliptic flow coefficient is studied in a hydrodynamic model, using a variety of different initializations which model the initial energy or entropy production process as a hard or soft process, respectively. While the charged multiplicity depends strongly on the chosen initialization, the p{sub T}-integrated elliptic flow for charged particles as a function of charged particle multiplicity and the p{sub T}-differential elliptic flow for charged particles in minimum bias events turn out to be almost independent of the initialization.

  17. Multiple Distributed Smart Microgrids with a Self-Autonomous, Energy Harvesting Wireless Sensor Network

    Guerrero, Josep M.; Kheng Tan, Yen

    2012-01-01

    The chapter covers the smart wireless sensors for microgrids, as well as the energy harvesting technology used to sustain the operations of these sensors. Last, a case study on the multiple distributed smart microgrids with a self-autonomous, energy harvesting wireless sensor network is presented....

  18. Lower Bounds on the Maximum Energy Benefit of Network Coding for Wireless Multiple Unicast

    Goseling, J.; Matsumoto, R.; Uyematsu, T.; Weber, J.H.

    2010-01-01

    We consider the energy savings that can be obtained by employing network coding instead of plain routing in wireless multiple unicast problems. We establish lower bounds on the benefit of network coding, defined as the maximum of the ratio of the minimum energy required by routing and network coding

  19. Lower bounds on the maximum energy benefit of network coding for wireless multiple unicast

    Goseling, Jasper; Matsumoto, Ryutaroh; Uyematsu, Tomohiko; Weber, Jos H.

    2010-01-01

    We consider the energy savings that can be obtained by employing network coding instead of plain routing in wireless multiple unicast problems. We establish lower bounds on the benefit of network coding, defined as the maximum of the ratio of the minimum energy required by routing and network coding

  20. Multiplicity fluctuations of pions and protons at SPS energy – An in ...

    but none of them can explain all the datasets simultaneously. ... in a collision, a new parameter named as 'compound multiplicity' (nc = ng + ns ... sion plates by 32S beam with 200 A GeV incident energy at CERN SPS. ... (b) Grey particles: They are mainly fast target recoil protons with energy up to ..... occurs reverse result.

  1. Energy and exergy analysis of the turbo-generators and steam turbine for the main feed water pump drive on LNG carrier

    Mrzljak, Vedran; Poljak, Igor; Mrakovčić, Tomislav

    2017-01-01

    Highlights: • Two low-power steam turbines in the LNG carrier propulsion plant were investigated. • Energy and exergy efficiencies of both steam turbines vary between 46% and 62%. • The ambient temperature has a low impact on exergy efficiency of analyzed turbines. • The maximum efficiencies area of both turbines was investigated. • A method for increasing the turbo-generator efficiencies by 1–3% is presented. - Abstract: Nowadays, marine propulsion systems are mainly based on internal combustion diesel engines. Despite this fact, a number of LNG carriers have steam propulsion plants. In such plants, steam turbines are used not only for ship propulsion, but also for electrical power generation and main feed water pump drive. Marine turbo-generators and steam turbine for the main feed water pump drive were investigated on the analyzed LNG carrier with steam propulsion plant. The measurements of various operating parameters were performed and obtained data were used for energy and exergy analysis. All the measurements and calculations were performed during the ship acceleration. The analysis shows that the energy and exergy efficiencies of both analyzed low-power turbines vary between 46% and 62% what is significantly lower in comparison with the high-power steam turbines. The ambient temperature has a low impact on exergy efficiency of analyzed turbines (change in ambient temperature for 10 °C causes less than 1% change in exergy efficiency). The highest exergy efficiencies were achieved at the lowest observed ambient temperature. Also, the highest efficiencies were achieved at 71.5% of maximum developed turbo-generator power while the highest efficiencies of steam turbine for the main feed water pump drive were achieved at maximum turbine developed power. Replacing the existing steam turbine for the main feed water pump drive with an electric motor would increase the turbo-generator energy and exergy efficiencies for at least 1–3% in all analyzed

  2. Carrier concentration dependence of donor activation energy in n-type GaN epilayers grown on Si (1 1 1) by plasma-assisted MBE

    Kumar, Mahesh; Bhat, Thirumaleshwara N.; Roul, Basanta; Rajpalke, Mohana K.; Kalghatgi, A.T.; Krupanidhi, S.B.

    2012-01-01

    Highlights: ► The n-type GaN layers were grown by plasma-assisted molecular beam epitaxy. ► The optical characteristics of a donor level in Si-doped GaN were studied. ► Activation energy of a Si-related donor was estimated from temperature dependent PL measurements. ► PL peak positions, FWHM of PL and activation energies are found to be proportional to the cube root of carrier density. ► The involvement of donor levels is supported by the temperature-dependent electron concentration measurements. -- Abstract: The n-type GaN layers were grown by plasma-assisted MBE and either intentionally doped with Si or unintentionally doped. The optical characteristics of a donor level in Si-doped, GaN were studied in terms of photoluminescence (PL) spectroscopy as a function of electron concentration. Temperature dependent PL measurements allowed us to estimate the activation energy of a Si-related donor from temperature-induced decay of PL intensity. PL peak positions, full width at half maximum of PL and activation energies are found to be proportional to the cube root of carrier density. The involvement of donor levels is supported by the temperature-dependent electron concentration measurements.

  3. Technical and economic data biomass-based energy conversion systems for the production of gaseous and/or liquid energy carriers

    2000-02-01

    The objectives of this study are: (1) to give an indication of the expected development of the currently mainly fossil fuel based Dutch energy supply system to a future CO 2 -emission 'free' energy supply system, and (2) to present main technological, economic, and environmental characteristics of three promising renewable energy based technologies for the production of gaseous and/or liquid secondary energy carriers and/or electricity and/or heat, viz.: (a) biomass hydrogasification for SNG (synthetic natural gas) production; (b) trigeneration of methanol and CHP (combined heat and power) from biomass by integrating a 'once-through' LPMEOH (liquid phase methanol) process into a 'conventional BIG/CC (Biomass-Integrated-Gasifier/Combined Cycle) system; and (c) trigeneration of Fischer-Tropsch derived transportation fuels and CHP from biomass by integrating a 'once-through' FT-process (Fischer-Tropsch) into a 'conventional' BIG/CC-system. Biomass conversion systems, for the production of CHP, transportation fuels, and as biofeedstock for the petrochemical industry, will play a substantial role in meeting the future Dutch renewable energy policy goals. In case fossil fuel prices remain low, additional policies are needed to reach these goals. Biomass will also play a significant role in reaching significant CO 2 emission reduction in Western Europe. In which sector the limited amount of biomass available/contractable can be applied best is still unclear, and therefore needs further research. By biomass hydrogasification it is possible to produce SNG with more or less the same composition as Groningen natural gas. In case relatively cheap hydrogen-rich waste gas streams are used in the short-term, the SNG production costs will he in the same order of magnitude as the market price for Dutch natural gas for small consumers (fl 0.6/Nm 3 ). The calculated minimum production costs for the 'green' fuels (methanol: 15 Euroct/l or 9 Euro/GJ, and FT-fuels: 27 Euroct/l or 9 Euro

  4. Energy, target, projectile and multiplicity dependences of intermittency behaviour in high energy O(Si,S) induced interactions

    Adamovich, M.I.; Alexandrov, Y.A.; Chernyavski, M.M.; Gerassimov, S.G.; Kharlamov, S.P.; Larionova, V.G.; Maslennikova, N.V.; Orlova, G.I.; Peresadko, N.G.; Salmanova, N.A.; Tretyakova, M.I.; Ameeva, Z.U.; Andreeva, N.P.; Anzon, Z.V.; Bubnov, V.I.; Chasnikov, I.Y.; Eligbaeva, G.Z.; Eremenko, G.Z.; Gaitinov, A.S.; Kalyachkina, G.S.; Kanygina, E.K.; Skakhova, C.I.; Bhalla, K.B.; Kumar, V.; Lal, P.; Lokanathan, S.; Mookerjee, S.; Raniwala, R.; Raniwala, S.; Burnett, T.H.; Grote, J.; Koss, T.; Lord, J.; Skelding, D.; Strausz, S.C.; Wilkes, R.J.; Cai, X.; Huang, H.; Liu, L.S.; Qian, W.Y.; Wang, H.Q.; Zhou, D.C.; Zhou, J.C.; Chernova, L.P.; Gadzhieva, S.I.; Gulamov, K.G.; Kadyrov, F.G.; Lukicheva, N.S.; Navotny, V.S.; Svechnikova, L.N.; Friedlander, E.M.; Heckman, H.H.; Lindstrom, P.J.; Garpman, S.; Jakobsson, B.; Otterlund, I.; Persson, S.; Soederstroem, K.; Stenlund, E.; Judek, B.; Nasyrov, S.H.; Petrov, N.V.; Xu, G.F.; Zheng, P.Y.

    1991-01-01

    Fluctuations of charged particles in high energy oxygen, silicon and sulphur induced interactions are investigated with the method of scaled factorial moments. It is found that for decreasing bin size down to δη∝0.1 the EMU01 data exhibits intermittent behaviour. The intermittency indexes are found to decrease with increasing incident energy and multiplicity and to increase with increasing target mass. It seems also to increase as the projectile mass increases. (orig.)

  5. Efficient free energy calculations for compounds with multiple stable conformations separated by high energy barriers

    Hritz, J.; Oostenbrink, C.

    2009-01-01

    Compounds with high intramolecular energy barriers represent challenging targets for free energy calculations because of the difficulty to obtain sufficient conformational sampling. Existing approaches are therefore computationally very demanding, thus preventing practical applications for such

  6. Energy

    Meister, F.; Ott, F.

    2002-01-01

    This chapter gives an overview of the current energy economy in Austria. The Austrian political aims of sustainable development and climate protection imply a reorientation of the Austrian energy policy as a whole. Energy consumption trends (1993-1998), final energy consumption by energy carrier (indexed data 1993-1999), comparative analysis of useful energy demand (1993 and 1999) and final energy consumption of renewable energy sources by sector (1996-1999) in Austria are given. The necessary measures to be taken in order to reduce the energy demand and increased the use of renewable energy are briefly mentioned. Figs. 5. (nevyjel)

  7. A review of multi-energy system planning and optimization tools for sustainable urban development

    Beuzekom, van I.; Gibescu, M.; Slootweg, J.G.

    2015-01-01

    Implementing renewable energy resources to enable sustainable development of cities, requires a more flexible and re-silient energy system than currently present. Integrating multiple energy carriers and services allow more efficient implementation of these renewables. Although most research efforts

  8. Energy farming in multiple land use : An opportunity for energy crop introduction in the Netherlands

    Londo, H.M.

    2002-01-01

    Concerns about climate change related to fossil fuel carbon dioxide emissions require the development of alternative energy resources. In most scenario studies on future energy supply, bio-energy is one of the dominant renewable alternatives foreseen. Apart from the use of residues and wastes, the

  9. Accelerated Enveloping Distribution Sampling: Enabling Sampling of Multiple End States while Preserving Local Energy Minima.

    Perthold, Jan Walther; Oostenbrink, Chris

    2018-05-17

    Enveloping distribution sampling (EDS) is an efficient approach to calculate multiple free-energy differences from a single molecular dynamics (MD) simulation. However, the construction of an appropriate reference-state Hamiltonian that samples all states efficiently is not straightforward. We propose a novel approach for the construction of the EDS reference-state Hamiltonian, related to a previously described procedure to smoothen energy landscapes. In contrast to previously suggested EDS approaches, our reference-state Hamiltonian preserves local energy minima of the combined end-states. Moreover, we propose an intuitive, robust and efficient parameter optimization scheme to tune EDS Hamiltonian parameters. We demonstrate the proposed method with established and novel test systems and conclude that our approach allows for the automated calculation of multiple free-energy differences from a single simulation. Accelerated EDS promises to be a robust and user-friendly method to compute free-energy differences based on solid statistical mechanics.

  10. Charged multiplicity distributions and correlations in e+e- annihilation at PETRA energies

    Braunschweig, W.; Gerhards, R.; Kirschfink, F.J.; Martyn, H.U.; Kolanoski, H.; Bowler, M.G.; Burrows, P.N.; Veitch, M.E.; Brandt, S.; Holder, M.; Caldwell, A.; Muller, D.; Ritz, S.; Strom, D.; Takashima, M.; Wu Saulan; Zobernig, G.

    1989-01-01

    We report on an analysis of the multiplicity distributions of charged particles produced in e + e - annihilation into hadrons at c.m. energies between 14 and 46.8 GeV. The charged multiplicity distributions of the whole event and single hemisphere deviate significantly from the Poisson distribution but follow approximate KNO scaling. We have also studied the multiplicity distributions in various rapidity intervals and found that they can be well described by the negative binomial distribution only for small central intervals. We have also analysed forward-backward multiplicity correlations for different energies and selections of particle charge and shown that they can be understood in terms of the fragmentation properties of the different quark flavours and by the production and decay of resonances. These correlations are well reproduced by the Lund string model. (orig.)

  11. Smart transactive energy framework in grid-connected multiple home microgrids under independent and coalition operations

    Marzband, Mousa; Azarinejadian, Fatemeh; Savaghebi, Mehdi

    2018-01-01

    This paper presents a smart Transactive energy (TE) framework in which home microgrids (H-MGs) can collaborate with each other in a multiple H-MG system by forming coalitions for gaining competitiveness in the market. Profit allocation due to coalition between H-MGs is an important issue...... for ensuring the optimal use of installed resources in the whole multiple H-MG system. In addition, considering demand fluctuations, energy production based on renewable resources in the multiple H-MG can be accomplished by demand-side management strategies that try to establish mechanisms to allow...... for a flatter demand curve. In this regard, demand shifting potential can be tapped through shifting certain amounts of energy demand from some time periods to others with lower expected demand, typically to match price values and to ensure that existing generation will be economically sufficient. It is also...

  12. Multiple criteria decision making for sustainable energy and transportation systems. Proceedings

    Ehrgott, Matthias [Auckland Univ. (New Zealand). Dept. of Engineering Science; Naujoks, Boris [Login GmbH, Schwelm (Germany).; Stewart, Theodor J. [Cape Town Univ., Rondebosch (South Africa). Dept. of Statistical Sciences; Wallenius, Jyrki (eds.) [Helsinki School of Economics (Finland). Dept. of Business Technology

    2010-07-01

    In the twenty-first century the sustainability of energy and transportation systems is on the top of the political agenda in many countries around the world and governments are establishing policies towards a sustainable, low emissions energy future. Environmental impacts of human economic activity necessitate the consideration of conflicting goals in decision making processes to develop sustainable systems. Any sustainable development has to reconcile conflicting economic and environmental objectives and criteria. The science of multiple criteria decision making has a lot to offer in addressing this need. Decision making with multiple (conflicting) criteria is the topic of research that is at the heart of the International Society of Multiple Criteria Decision Making. This book is based on selected papers presented at the societies 19th International Conference, held at The University of Auckland, New Zealand, from 7th to 12th January 2008 under the theme ''MCDM for Sustainable Energy and Transportation Systems''. (orig.)

  13. Hadronic multiplicity and total cross-section: a new scaling in wide energy range

    Kobylinsky, N.A.; Martynov, E.S.; Shelest, V.P.

    1983-01-01

    The ratio of mean multiplicity to total cross-section is shown to be the same for all the Regge models and to rise with energy as lns which is confirmed by experimental data. Hence, a power of multiplicity growth is unambiguously connected with that of total cross-section. As regards the observed growth, approximately ln 2 s, it tells about a dipole character of pomeron singularity

  14. Incorporating Multiple Energy Relay Dyes in Liquid Dye-Sensitized Solar Cells

    Yum, Jun-Ho

    2011-01-05

    Panchromatic response is essential to increase the light-harvesting efficiency in solar conversion systems. Herein we show increased light harvesting from using multiple energy relay dyes inside dye-sensitized solar cells. Additional photoresponse from 400-590 nm matching the optical window of the zinc phthalocyanine sensitizer was observed due to Förster resonance energy transfer (FRET) from the two energy relay dyes to the sensitizing dye. The complementary absorption spectra of the energy relay dyes and high excitation transfer efficiencies result in a 35% increase in photovoltaic performance. © 2011 Wiley-VCH Verlag GmbH& Co. KGaA.

  15. Determination of shell correction energies at saddle point using pre-scission neutron multiplicities

    Golda, K.S.; Saxena, A.; Mittal, V.K.; Mahata, K.; Sugathan, P.; Jhingan, A.; Singh, V.; Sandal, R.; Goyal, S.; Gehlot, J.; Dhal, A.; Behera, B.R.; Bhowmik, R.K.; Kailas, S.

    2013-01-01

    Pre-scission neutron multiplicities have been measured for 12 C + 194, 198 Pt systems at matching excitation energies at near Coulomb barrier region. Statistical model analysis with a modified fission barrier and level density prescription have been carried out to fit the measured pre-scission neutron multiplicities and the available evaporation residue and fission cross sections simultaneously to constrain statistical model parameters. Simultaneous fitting of the pre-scission neutron multiplicities and cross section data requires shell correction at the saddle point

  16. Multiple Coulomb scattering of high-energy heavy charged particle beams used in biology and medicine

    Wong, M.; Schimmerling, W.; Ludewigt, B.; Phillips, M.; Curtis, S.; Tobias, C.A.

    1987-01-01

    The authors measured lateral displacement and angular distributions of high-energy heavy charged particles emerging from a target at the Lawrence Berkeley Laboratory BEVALAC with beams used in radiobiology experiments. Multiple Coulomb scattering occurring in the target material generally spreads the beam laterally and increases its divergence. The apparatus consists of four sets of position-sensitive semiconductor detectors located along the beam line. Each providing two position signals and one energy signal. The difference between the two position signals is used to determine the particle position in one dimension. The two position signals are constrained to add up to the energy deposition signal in order to reject multiple-particle traversals. The vector directions for the incident and emerging particles are reconstructed in three dimensions from their measured coordinated positions. Lateral and angular distributions are reported for beams of high-energy neon, iron and uranium ions incident on targets of aluminum, cooper, lead and water

  17. Research on Energy-Saving Operation Strategy for Multiple Trains on the Urban Subway Line

    Jianqiang Liu

    2017-12-01

    Full Text Available Energy consumption for multiple trains on the urban subway line is predominantly affected by the operation strategy. This paper proposed an energy-saving operation strategy for multiple trains, which is suitable for various line conditions and complex train schedules. The model and operation modes of the strategy are illustrated in detail, aiming to take full use of regenerative braking energy in complex multi-train systems with different departure intervals and dwell times. The computing method is proposed by means of the heuristic algorithm to obtain the optimum operation curve for each train. The simulation result based on a real urban subway line is provided to verify the correctness and effectiveness of the proposed energy-saving operation strategy.

  18. Upgrading the Glycerol from Biodiesel Production as a Source of Energy Carriers and Chemicals—A Technological Review for Three Chemical Pathways

    Abel Rodrigues

    2017-11-01

    Full Text Available Glycerol is a by-product of biodiesel obtained from biomass, accounting for 10% of the biodiesel production. In the context of a green economy, aiming for a reduction of the emission of atmospheric greenhouse gases emissions, the demand of biodiesel is expected to increase vastly, in parallel with a side glut supply of glycerol. Given the high cost of biodiesel compared with its fossil congener, upgrading of glycerol into added-value products can represent a secondary income source and turn the production of such alternative fuels economically sustainable in the long term. The glycerol obtained as by-product of biodiesel from biomass is in a crude form and must be purified. Some industrial solutions and applications were therein geared. The survey presented in this work, based on a reviewing of the existing literature, examines three routes for the valuing glycerol into energy carriers and chemicals, namely, carbonation, acylation, and steam reforming to hydrogen. The latter is embodied of great interest and importance, insofar that hydrogen by itself is considered as straighforward clean fuel for transportation uses, due to its high calorific power and to recent advances in fuel cells. We also have focused on the chain value from biomass to energies carriers through these pathways.

  19. Misconceptions and biases in German students' perception of multiple energy sources: implications for science education

    Lee, Roh Pin

    2016-04-01

    Misconceptions and biases in energy perception could influence people's support for developments integral to the success of restructuring a nation's energy system. Science education, in equipping young adults with the cognitive skills and knowledge necessary to navigate in the confusing energy environment, could play a key role in paving the way for informed decision-making. This study examined German students' knowledge of the contribution of diverse energy sources to their nation's energy mix as well as their affective energy responses so as to identify implications for science education. Specifically, the study investigated whether and to what extent students hold mistaken beliefs about the role of multiple energy sources in their nation's energy mix, and assessed how misconceptions could act as self-generated reference points to underpin support/resistance of proposed developments. An in-depth analysis of spontaneous affective associations with five key energy sources also enabled the identification of underlying concerns driving people's energy responses and facilitated an examination of how affective perception, in acting as a heuristic, could lead to biases in energy judgment and decision-making. Finally, subgroup analysis differentiated by education and gender supported insights into a 'two culture' effect on energy perception and the challenge it poses to science education.

  20. Multiple scattering expansion of the self-energy at finite temperature

    Jeon, S.; Ellis, P.J.

    1998-01-01

    An often used rule that the thermal correction to the self-energy is the thermal phase-space times the forward scattering amplitude from target particles is shown to be the leading term in an exact multiple scattering expansion. Starting from imaginary-time finite-temperature field theory, a rigorous expansion for the retarded self-energy is derived. The relationship to the thermodynamic potential is briefly discussed. copyright 1998 The American Physical Society

  1. Multiple Scattering Expansion of the Self-Energy at Finite Temperature

    Jeon, Sangyong; Ellis, Paul J.

    1998-01-01

    An often used rule that the thermal correction to the self-energy is the thermal phase-space times the forward scattering amplitude from target particles is shown to be the leading term in an exact multiple scattering expansion. Starting from imaginary-time finite-temperature field theory, a rigorous expansion for the retarded self-energy is derived. The relationship to the thermodynamic potential is briefly discussed.

  2. Identification of optimal strategies for energy management systems planning under multiple uncertainties

    Cai, Y.P.; Huang, G.H.; Yang, Z.F.; Tan, Q.

    2009-01-01

    Management of energy resources is crucial for many regions throughout the world. Many economic, environmental and political factors are having significant effects on energy management practices, leading to a variety of uncertainties in relevant decision making. The objective of this research is to identify optimal strategies in the planning of energy management systems under multiple uncertainties through the development of a fuzzy-random interval programming (FRIP) model. The method is based on an integration of the existing interval linear programming (ILP), superiority-inferiority-based fuzzy-stochastic programming (SI-FSP) and mixed integer linear programming (MILP). Such a FRIP model allows multiple uncertainties presented as interval values, possibilistic and probabilistic distributions, as well as their combinations within a general optimization framework. It can also be used for facilitating capacity-expansion planning of energy-production facilities within a multi-period and multi-option context. Complexities in energy management systems can be systematically reflected, thus applicability of the modeling process can be highly enhanced. The developed method has then been applied to a case of long-term energy management planning for a region with three cities. Useful solutions for the planning of energy management systems were generated. Interval solutions associated with different risk levels of constraint violation were obtained. They could be used for generating decision alternatives and thus help decision makers identify desired policies under various economic and system-reliability constraints. The solutions can also provide desired energy resource/service allocation and capacity-expansion plans with a minimized system cost, a maximized system reliability and a maximized energy security. Tradeoffs between system costs and constraint-violation risks could be successfully tackled, i.e., higher costs will increase system stability, while a desire for lower

  3. Basic and energy physics: the multiple faces of energy; Physique fondamentale et energetique: les multiples visages de l'energie

    Balian, R. [Academie des Sciences, 75 - Paris (France)

    2001-07-01

    After an historical presentation of the elaboration of the energy concept, this document recalls, first, the basic physical principles linked with this concept: first and second principle of thermodynamics, dynamics of irreversible processes, hierarchy of elementary interactions. Then, their consequences on energy problems are examined by comparing the different common types of energy from different points of view: concentration, degradation, transport, storage, reserves and harmful effects. These comparisons rely on the characteristic values of the data involved. (J.S.)

  4. A Multiple Period Problem in Distributed Energy Management Systems Considering CO2 Emissions

    Muroda, Yuki; Miyamoto, Toshiyuki; Mori, Kazuyuki; Kitamura, Shoichi; Yamamoto, Takaya

    Consider a special district (group) which is composed of multiple companies (agents), and where each agent responds to an energy demand and has a CO2 emission allowance imposed. A distributed energy management system (DEMS) optimizes energy consumption of a group through energy trading in the group. In this paper, we extended the energy distribution decision and optimal planning problem in DEMSs from a single period problem to a multiple periods one. The extension enabled us to consider more realistic constraints such as demand patterns, the start-up cost, and minimum running/outage times of equipment. At first, we extended the market-oriented programming (MOP) method for deciding energy distribution to the multiple periods problem. The bidding strategy of each agent is formulated by a 0-1 mixed non-linear programming problem. Secondly, we proposed decomposing the problem into a set of single period problems in order to solve it faster. In order to decompose the problem, we proposed a CO2 emission allowance distribution method, called an EP method. We confirmed that the proposed method was able to produce solutions whose group costs were close to lower-bound group costs by computational experiments. In addition, we verified that reduction in computational time was achieved without losing the quality of solutions by using the EP method.

  5. Lifetime Optimization of a Multiple Sink Wireless Sensor Network through Energy Balancing

    Tapan Kumar Jain

    2015-01-01

    Full Text Available The wireless sensor network consists of small limited energy sensors which are connected to one or more sinks. The maximum energy consumption takes place in communicating the data from the nodes to the sink. Multiple sink WSN has an edge over the single sink WSN where very less energy is utilized in sending the data to the sink, as the number of hops is reduced. If the energy consumed by a node is balanced between the other nodes, the lifetime of the network is considerably increased. The network lifetime optimization is achieved by restructuring the network by modifying the neighbor nodes of a sink. Only those nodes are connected to a sink which makes the total energy of the sink less than the threshold. This energy balancing through network restructuring optimizes the network lifetime. This paper depicts this fact through simulations done in MATLAB.

  6. Dependence of Xmax and multiplicity of electron and muon on different high energy interaction models

    G Rastegarzadeh

    2010-06-01

    Full Text Available Different high energy interaction models are the applied in CORSIKA code to simulate Extensive Air Showers (EAS generated by Cosmic Rays (CR. In this work the effects of QGSJET01, QGSJETII, DPMJET, SIBYLL models on Xmax and multiplicity of secondary electrons and muons at observation level are studied.

  7. Energy-optimal motion planning for multiple robotic vehicles with collision avoidance

    Häusler, A.J.; Saccon, A.; Aguiar, A.P.; Hauser, J.; Pascoal, A.M.

    2016-01-01

    We propose a numerical algorithm for multiple-vehicle motion planning that explicitly takes into account the vehicle dynamics, temporal and spatial specifications, and energy-related requirements. As a motivating example, we consider the case where a group of vehicles is tasked to reach a number of

  8. Relaxation height in energy landscapes : an application to multiple metastable states

    Cirillo, E.N.M.; Nardi, F.R.

    2012-01-01

    The study of systems with multiple (not necessarily degenerate) metastable states presents subtle difficulties from the mathematical point of view related to the variational problem that has to be solved in these cases. We introduce the notion of relaxation height in a general energy landscape and

  9. Smart transactive energy framework in grid-connected multiple home microgrids under independent and coalition operations

    Marzband, Mousa; Azarinejadian, Fatemeh; Savaghebi, Mehdi

    2018-01-01

    This paper presents a smart Transactive energy (TE) framework in which home microgrids (H-MGs) can collaborate with each other in a multiple H-MG system by forming coalitions for gaining competitiveness in the market. Profit allocation due to coalition between H-MGs is an important issue...

  10. On the absence of multiple dips in diffraction of high energy hadrons

    Malecki; Michalec, M.; Pallotta, M.

    1997-07-01

    An unorthodox insight into the structure of the geometrical Chou-Yang model explains the experimentally observed paradox of elastic diffraction of high energy hadrons without multiple dips. It is pointed out that the shadow scattering, away from the forward peak, is governed by small values of the coupling strength

  11. Rational construction of multiple interfaces in ternary heterostructure for efficient spatial separation and transfer of photogenerated carriers in the application of photocatalytic hydrogen evolution

    Shi, Jian-Wen; Ma, Dandan; Zou, Yajun; Fan, Zhaoyang; Shi, Jinwen; Cheng, Linhao; Ji, Xin; Niu, Chunming

    2018-03-01

    The design of efficient and stable photocatalyst plays a critical role in the photocatalytic hydrogen evolution from water splitting. Herein, we develop a novel ZnS/CdS/ZnO ternary heterostructure by the in-situ sulfuration of CdS/ZnO, which includes four contact interfaces: CdS-ZnS interface, ZnS-ZnO interface, CdS-ZnO interface and ZnS-CdS-ZnO ternary interface, forming three charge carrier-transfer modes (type-I, type-II and direct Z-scheme) through five carrier-transfer pathways. As a result, the separation and transfer of photoexcited electron-hole pairs are promoted significantly, resulting in a high hydrogen evolution rate of 44.70 mmol h-1 g-1, which is 2, 3.7 and 8 times higher than those of binary heterostructures, CdS/ZnO, CdS/ZnS and ZnS/ZnO, respectively, and 26.5, 280 and 298 times higher than those of single CdS, ZnO and ZnS, respectively. As a counterpart ternary heterostructure, CdS/ZnS/ZnO contains only two interfaces: CdS-ZnS interface and ZnS-ZnO interface, which form two charge carrier-transfer modes (type-I and type-II) through two carrier-transfer pathways, leading to its much lower hydrogen evolution rate (27.25 mmol h-1 g-1) than ZnS/CdS/ZnO ternary heterostructure. This work is relevant for understanding the charge-transfer pathways between multi-interfaces in multicomponent heterojunctions.

  12. The nuclear import of the human T lymphotropic virus type I (HTLV-1) tax protein is carrier- and energy-independent.

    Tsuji, Takahiro; Sheehy, Noreen; Gautier, Virginie W; Hayakawa, Hitoshi; Sawa, Hirofumi; Hall, William W

    2007-05-04

    HTLV-1 is the etiologic agent of the adult T cell leukemialymphoma (ATLL). The viral regulatory protein Tax plays a central role in leukemogenesis as a transcriptional transactivator of both viral and cellular gene expression, and this requires Tax activity in both the cytoplasm and the nucleus. In the present study, we have investigated the mechanisms involved in the nuclear localization of Tax. Employing a GFP fusion expression system and a range of Tax mutants, we could confirm that the N-terminal 60 amino acids, and specifically residues within the zinc finger motif in this region, are important for nuclear localization. Using an in vitro nuclear import assay, it could be demonstrated that the transportation of Tax to the nucleus required neither energy nor carrier proteins. Specific and direct binding between Tax and p62, a nucleoporin with which the importin beta family of proteins have been known to interact was also observed. The nuclear import activity of wild type Tax and its mutants and their binding affinity for p62 were also clearly correlated, suggesting that the entry of Tax into the nucleus involves a direct interaction with nucleoporins within the nuclear pore complex (NPC). The nuclear export of Tax was also shown to be carrier independent. It could be also demonstrated that Tax it self may have a carrier function and that the NF-kappaB subunit p65 could be imported into the nucleus by Tax. These studies suggest that Tax could alter the nucleocytoplasmic distribution of cellular proteins, and this could contribute to the deregulation of cellular processes observed in HTLV-1 infection.

  13. Damping-tunable energy-harvesting vehicle damper with multiple controlled generators: Design, modeling and experiments

    Xie, Longhan; Li, Jiehong; Li, Xiaodong; Huang, Ledeng; Cai, Siqi

    2018-01-01

    Hydraulic dampers are used to decrease the vibration of a vehicle, where vibration energy is dissipated as heat. In addition to resulting in energy waste, the damping coefficient in hydraulic dampers cannot be changed during operation. In this paper, an energy-harvesting vehicle damper was proposed to replace traditional hydraulic dampers. The goal is not only to recover kinetic energy from suspension vibration but also to change the damping coefficient during operation according to road conditions. The energy-harvesting damper consists of multiple generators that are independently controlled by switches. One of these generators connects to a tunable resistor for fine tuning the damping coefficient, while the other generators are connected to a control and rectifying circuit, each of which both regenerates electricity and provides a constant damping coefficient. A mathematical model was built to investigate the performance of the energy-harvesting damper. By controlling the number of switched-on generators and adjusting the value of the external tunable resistor, the damping can be fine tuned according to the requirement. In addition to the capability of damping tuning, the multiple controlled generators can output a significant amount of electricity. A prototype was built to test the energy-harvesting damper design. Experiments on an MTS testing system were conducted, with results that validated the theoretical analysis. Experiments show that changing the number of switched-on generators can obviously tune the damping coefficient of the damper and simultaneously produce considerable electricity.

  14. An optical study of multiple NEIAL events driven by low energy electron precipitation

    J. M. Sullivan

    2008-08-01

    Full Text Available Optical data are compared with EISCAT radar observations of multiple Naturally Enhanced Ion-Acoustic Line (NEIAL events in the dayside cusp. This study uses narrow field of view cameras to observe small-scale, short-lived auroral features. Using multiple-wavelength optical observations, a direct link between NEIAL occurrences and low energy (about 100 eV optical emissions is shown. This is consistent with the Langmuir wave decay interpretation of NEIALs being driven by streams of low-energy electrons. Modelling work connected with this study shows that, for the measured ionospheric conditions and precipitation characteristics, growth of unstable Langmuir (electron plasma waves can occur, which decay into ion-acoustic wave modes. The link with low energy optical emissions shown here, will enable future studies of the shape, extent, lifetime, grouping and motions of NEIALs.

  15. Hot carrier degradation in semiconductor devices

    2015-01-01

    This book provides readers with a variety of tools to address the challenges posed by hot carrier degradation, one of today’s most complicated reliability issues in semiconductor devices.  Coverage includes an explanation of carrier transport within devices and book-keeping of how they acquire energy (“become hot”), interaction of an ensemble of colder and hotter carriers with defect precursors, which eventually leads to the creation of a defect, and a description of how these defects interact with the device, degrading its performance. • Describes the intricacies of hot carrier degradation in modern semiconductor technologies; • Covers the entire hot carrier degradation phenomenon, including topics such as characterization, carrier transport, carrier-defect interaction, technological impact, circuit impact, etc.; • Enables detailed understanding of carrier transport, interaction of the carrier ensemble with the defect precursors, and an accurate assessment of how the newly created defects imp...

  16. Effect of multiple phase change materials (PCMs) slab configurations on thermal energy storage

    Shaikh, Shadab; Lafdi, Khalid

    2006-01-01

    The present work involves the use of a two dimensional control volume based numerical method to conduct a study of a combined convection-diffusion phase change heat transfer process in varied configurations of composite PCM slabs. Simulations were conducted to investigate the impact of using different configurations of multiple PCM slabs arrangements with different melting temperatures, thermophysical properties and varied sets of boundary conditions on the total energy stored as compared to using a single PCM slab. The degree of enhancement of the energy storage has been shown in terms of the total energy stored rate. The numerical results from the parametric study indicated that the total energy charged rate can be significantly enhanced by using composite PCMs as compared to the single PCM. This enhancement in the energy storage can be of great importance to improve the thermal performance of latent thermal storage systems

  17. Aircraft Carriers

    Nødskov, Kim; Kværnø, Ole

    as their purchases of aircraft carrier systems, makes it more than likely that the country is preparing such an acquisition. China has territorial disputes in the South China Sea over the Spratly Islands and is also worried about the security of its sea lines of communications, by which China transports the majority......, submarines, aircraft and helicopters, is not likely to be fully operational and war-capable until 2020, given the fact that China is starting from a clean sheet of paper. The United States of America (USA), the United Kingdom (UK), Russia and India are currently building or have made decisions to build new...

  18. CALCULATING SEPARATE MAGNETIC FREE ENERGY ESTIMATES FOR ACTIVE REGIONS PRODUCING MULTIPLE FLARES: NOAA AR11158

    Tarr, Lucas; Longcope, Dana; Millhouse, Margaret [Department of Physics, Montana State University, Bozeman, MT 59717 (United States)

    2013-06-10

    It is well known that photospheric flux emergence is an important process for stressing coronal fields and storing magnetic free energy, which may then be released during a flare. The Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory (SDO) captured the entire emergence of NOAA AR 11158. This region emerged as two distinct bipoles, possibly connected underneath the photosphere, yet characterized by different photospheric field evolutions and fluxes. The combined active region complex produced 15 GOES C-class, two M-class, and the X2.2 Valentine's Day Flare during the four days after initial emergence on 2011 February 12. The M and X class flares are of particular interest because they are nonhomologous, involving different subregions of the active region. We use a Magnetic Charge Topology together with the Minimum Current Corona model of the coronal field to model field evolution of the complex. Combining this with observations of flare ribbons in the 1600 A channel of the Atmospheric Imaging Assembly on board SDO, we propose a minimization algorithm for estimating the amount of reconnected flux and resulting drop in magnetic free energy during a flare. For the M6.6, M2.2, and X2.2 flares, we find a flux exchange of 4.2 Multiplication-Sign 10{sup 20} Mx, 2.0 Multiplication-Sign 10{sup 20} Mx, and 21.0 Multiplication-Sign 10{sup 20} Mx, respectively, resulting in free energy drops of 3.89 Multiplication-Sign 10{sup 30} erg, 2.62 Multiplication-Sign 10{sup 30} erg, and 1.68 Multiplication-Sign 10{sup 32} erg.

  19. An energy efficient distance-aware routing algorithm with multiple mobile sinks for wireless sensor networks.

    Wang, Jin; Li, Bin; Xia, Feng; Kim, Chang-Seob; Kim, Jeong-Uk

    2014-08-18

    Traffic patterns in wireless sensor networks (WSNs) usually follow a many-to-one model. Sensor nodes close to static sinks will deplete their limited energy more rapidly than other sensors, since they will have more data to forward during multihop transmission. This will cause network partition, isolated nodes and much shortened network lifetime. Thus, how to balance energy consumption for sensor nodes is an important research issue. In recent years, exploiting sink mobility technology in WSNs has attracted much research attention because it can not only improve energy efficiency, but prolong network lifetime. In this paper, we propose an energy efficient distance-aware routing algorithm with multiple mobile sink for WSNs, where sink nodes will move with a certain speed along the network boundary to collect monitored data. We study the influence of multiple mobile sink nodes on energy consumption and network lifetime, and we mainly focus on the selection of mobile sink node number and the selection of parking positions, as well as their impact on performance metrics above. We can see that both mobile sink node number and the selection of parking position have important influence on network performance. Simulation results show that our proposed routing algorithm has better performance than traditional routing ones in terms of energy consumption.

  20. An Energy Efficient Distance-Aware Routing Algorithm with Multiple Mobile Sinks for Wireless Sensor Networks

    Jin Wang

    2014-08-01

    Full Text Available Traffic patterns in wireless sensor networks (WSNs usually follow a many-to-one model. Sensor nodes close to static sinks will deplete their limited energy more rapidly than other sensors, since they will have more data to forward during multihop transmission. This will cause network partition, isolated nodes and much shortened network lifetime. Thus, how to balance energy consumption for sensor nodes is an important research issue. In recent years, exploiting sink mobility technology in WSNs has attracted much research attention because it can not only improve energy efficiency, but prolong network lifetime. In this paper, we propose an energy efficient distance-aware routing algorithm with multiple mobile sink for WSNs, where sink nodes will move with a certain speed along the network boundary to collect monitored data. We study the influence of multiple mobile sink nodes on energy consumption and network lifetime, and we mainly focus on the selection of mobile sink node number and the selection of parking positions, as well as their impact on performance metrics above. We can see that both mobile sink node number and the selection of parking position have important influence on network performance. Simulation results show that our proposed routing algorithm has better performance than traditional routing ones in terms of energy consumption.

  1. The rationale for energy efficiency policy: Assessing the recognition of the multiple benefits of energy efficiency retrofit policy

    Kerr, Niall; Gouldson, Andy; Barrett, John

    2017-01-01

    The rationale for energy efficiency policy can be framed in terms of a variety of different benefits. This paper considers how different benefits have been used within the overall rationale for energy efficient retrofit policy in different contexts. We posit that different rationales may be used for the same policy response, and that the form of rationale used may affect the design, delivery or the level of policy support, with different rationales making it easier to account for different results. Considering retrofit policy in the contexts of the UK, Germany, New Zealand and Ireland, we characterise policy rationale in each case, assessing what the key perceived benefits have been, and whether they have changed over time. The analysis identifies some marked differences between cases with the recognition of benefits and the ensuing policy rationale resulting from a complex mix of political, social and economic influences. We find that recognition of multiple benefits may not equate with multiplied policy support, and instead it is more likely that different rationales will have relevance at different times, for different audiences. The findings highlight that, alongside evidence for policy, it is important to also consider how the overall rationale for policy is eventually framed. - Highlights: • Energy efficiency as a policy issue with perceived multiple benefits. • Assessment of the influence of different benefits on rationale for energy efficient retrofit policy. • How does the rationale for retrofit policy differ in different national policy contexts. • To what extent are the perceived multiple benefits of policy recognised. • What influence does eventual rationale for policy have on the policy implemented.

  2. Effects of pre-existing anti-carrier immunity and antigenic element multiplicity on efficacy of a modular virus-like particle vaccine.

    Chuan, Yap P; Rivera-Hernandez, Tania; Wibowo, Nani; Connors, Natalie K; Wu, Yang; Hughes, Fiona K; Lua, Linda H L; Middelberg, Anton P J

    2013-09-01

    Modularization of a peptide antigen for presentation on a microbially synthesized murine polyomavirus (MuPyV) virus-like particle (VLP) offers a new alternative for rapid and low-cost vaccine delivery at a global scale. In this approach, heterologous modules containing peptide antigenic elements are fused to and displayed on the VLP carrier, allowing enhancement of peptide immunogenicity via ordered and densely repeated presentation of the modules. This study addresses two key engineering questions pertaining to this platform, exploring the effects of (i) pre-existing carrier-specific immunity on modular VLP vaccine effectiveness and (ii) increase in the antigenic element number per VLP on peptide-specific immune response. These effects were studied in a mouse model and with modular MuPyV VLPs presenting a group A streptococcus (GAS) peptide antigen, J8i. The data presented here demonstrate that immunization with a modular VLP could induce high levels of J8i-specific antibodies despite a strong pre-existing anti-carrier immune response. Doubling of the J8i antigenic element number per VLP did not enhance J8i immunogenicity at a constant peptide dose. However, the strategy, when used in conjunction with increased VLP dose, could effectively increase the peptide dose up to 10-fold, leading to a significantly higher J8i-specific antibody titer. This study further supports feasibility of the MuPyV modular VLP vaccine platform by showing that, in the absence of adjuvant, modularized GAS antigenic peptide at a dose as low as 150 ng was sufficient to raise a high level of peptide-specific IgGs indicative of bactericidal activity. Copyright © 2013 Wiley Periodicals, Inc.

  3. Scenarios for total utilisation of hydrogen as an energy carrier in the future Danish energy system. Final report; Scenarier for samlet udnyttelse af brint som energibaerer i Danmarks fremtidige energisystem. Slutrapport

    Hauge Petersen, A; Engberg Pedersen, T; Joergensen, K [and others

    2001-04-01

    This is the final report from a project performed for the Danish Energy Agency under its Hydrogen Programme. The project, which within the project group goes by the abbreviated title 'Hydrogen as an energy carrier', constructs and analyses different total energy scenarios for introducing hydrogen as an energy carrier, as energy storage medium and as a fuel in the future Danish energy system. The primary aim of the project is to study ways of handling the large deficits and surpluses of electricity from wind energy expected in the future Danish energy system. System-wide aspects of the choice of hydrogen production technologies, distribution methods, infrastructure requirements and conversion technologies are studied. Particularly, the possibility of using in the future the existing Danish natural gas distribution grid for carrying hydrogen will be assessed. For the year 2030, two scenarios are constructed: One using hydrogen primarily in the transportation sector, the other using it as a storage option for the centralised power plants still in operation by this year. For the year 2050, where the existing fossil power plants are expected to have been phased out completely, the scenarios for two possible developments are investigated: Either, there is a complete decentralisation of the use of hydrogen, converting and storing electricity surpluses into hydrogen in individual buildings, for later use in vehicles or regeneration of power and heat. Or, some centralised infrastructure is retained, such as hydrogen cavern stores and a network of vehicle hydrogen filling stations. The analysis is used to identify the components in an implementation strategy, for the most interesting scenarios, including a time sequence of necessary decisions and technology readiness. The report is in Danish, because it is part of the dissemination effort of the Hydrogen Committee, directed at the Danish population in general and the Danish professional community in particular. (au)

  4. Scenarios for total utilisation of hydrogen as an energy carrier in the future Danish energy system. Final report; Scenarier for samlet udnyttelse af brint som energibaerer i Danmarks fremtidige energisystem. Slutrapport

    Hauge Petersen, A.; Engberg Pedersen, T.; Joergensen, K. (and others)

    2001-04-01

    This is the final report from a project performed for the Danish Energy Agency under its Hydrogen Programme. The project, which within the project group goes by the abbreviated title 'Hydrogen as an energy carrier', constructs and analyses different total energy scenarios for introducing hydrogen as an energy carrier, as energy storage medium and as a fuel in the future Danish energy system. The primary aim of the project is to study ways of handling the large deficits and surpluses of electricity from wind energy expected in the future Danish energy system. System-wide aspects of the choice of hydrogen production technologies, distribution methods, infrastructure requirements and conversion technologies are studied. Particularly, the possibility of using in the future the existing Danish natural gas distribution grid for carrying hydrogen will be assessed. For the year 2030, two scenarios are constructed: One using hydrogen primarily in the transportation sector, the other using it as a storage option for the centralised power plants still in operation by this year. For the year 2050, where the existing fossil power plants are expected to have been phased out completely, the scenarios for two possible developments are investigated: Either, there is a complete decentralisation of the use of hydrogen, converting and storing electricity surpluses into hydrogen in individual buildings, for later use in vehicles or regeneration of power and heat. Or, some centralised infrastructure is retained, such as hydrogen cavern stores and a network of vehicle hydrogen filling stations. The analysis is used to identify the components in an implementation strategy, for the most interesting scenarios, including a time sequence of necessary decisions and technology readiness. The report is in Danish, because it is part of the dissemination effort of the Hydrogen Committee, directed at the Danish population in general and the Danish professional community in particular. (au)

  5. Performance of Uplink Carrier Aggregation in LTE-Advanced Systems

    Wang, Hua; Rosa, Claudio; Pedersen, Klaus

    2010-01-01

    Carrier aggregation (CA) has been proposed to aggregate two or more component carriers (CCs) to support a much wider transmission bandwidth for LTE-Advanced systems. With carrier aggregation, it is possible to schedule a user equipment (UE) on multiple component carriers simultaneously. In this p...

  6. Probability distributions in conservative energy exchange models of multiple interacting agents

    Scafetta, Nicola; West, Bruce J

    2007-01-01

    Herein we study energy exchange models of multiple interacting agents that conserve energy in each interaction. The models differ regarding the rules that regulate the energy exchange and boundary effects. We find a variety of stochastic behaviours that manifest energy equilibrium probability distributions of different types and interaction rules that yield not only the exponential distributions such as the familiar Maxwell-Boltzmann-Gibbs distribution of an elastically colliding ideal particle gas, but also uniform distributions, truncated exponential distributions, Gaussian distributions, Gamma distributions, inverse power law distributions, mixed exponential and inverse power law distributions, and evolving distributions. This wide variety of distributions should be of value in determining the underlying mechanisms generating the statistical properties of complex phenomena including those to be found in complex chemical reactions

  7. Coupled energy-drift and force-balance equations for high-field hot-carrier transport

    Huang, Danhong; Alsing, P.M.; Apostolova, T.; Cardimona, D.A.

    2005-01-01

    Coupled energy-drift and force-balance equations that contain a frictional force for the center-of-mass motion of electrons are derived for hot-electron transport under a strong dc electric field. The frictional force is found to be related to the net rate of phonon emission, which takes away the momentum of a phonon from an electron during each phonon-emission event. The net rate of phonon emission is determined by the Boltzmann scattering equation, which depends on the distribution of electrons interacting with phonons. The work done by the frictional force is included into the energy-drift equation for the electron-relative scattering motion and is found to increase the thermal energy of the electrons. The importance of the hot-electron effect in the energy-drift term under a strong dc field is demonstrated in reducing the field-dependent drift velocity and mobility. The Doppler shift in the energy conservation of scattering electrons interacting with impurities and phonons is found to lead to an anisotropic distribution of electrons in the momentum space along the field direction. The importance of this anisotropic distribution is demonstrated through a comparison with the isotropic energy-balance equation, from which we find that defining a state-independent electron temperature becomes impossible. To the leading order, the energy-drift equation is linearized with a distribution function by expanding it into a Fokker-Planck-type equation, along with the expansions of both the force-balance equation and the Boltzmann scattering equation for hot phonons

  8. Free Energy Reconstruction from Logarithmic Mean-Force Dynamics Using Multiple Nonequilibrium Trajectories.

    Morishita, Tetsuya; Yonezawa, Yasushige; Ito, Atsushi M

    2017-07-11

    Efficient and reliable estimation of the mean force (MF), the derivatives of the free energy with respect to a set of collective variables (CVs), has been a challenging problem because free energy differences are often computed by integrating the MF. Among various methods for computing free energy differences, logarithmic mean-force dynamics (LogMFD) [ Morishita et al., Phys. Rev. E 2012 , 85 , 066702 ] invokes the conservation law in classical mechanics to integrate the MF, which allows us to estimate the free energy profile along the CVs on-the-fly. Here, we present a method called parallel dynamics, which improves the estimation of the MF by employing multiple replicas of the system and is straightforwardly incorporated in LogMFD or a related method. In the parallel dynamics, the MF is evaluated by a nonequilibrium path-ensemble using the multiple replicas based on the Crooks-Jarzynski nonequilibrium work relation. Thanks to the Crooks relation, realizing full-equilibrium states is no longer mandatory for estimating the MF. Additionally, sampling in the hidden subspace orthogonal to the CV space is highly improved with appropriate weights for each metastable state (if any), which is hardly achievable by typical free energy computational methods. We illustrate how to implement parallel dynamics by combining it with LogMFD, which we call logarithmic parallel dynamics (LogPD). Biosystems of alanine dipeptide and adenylate kinase in explicit water are employed as benchmark systems to which LogPD is applied to demonstrate the effect of multiple replicas on the accuracy and efficiency in estimating the free energy profiles using parallel dynamics.

  9. Beyond Group: Multiple Person Tracking via Minimal Topology-Energy-Variation.

    Gao, Shan; Ye, Qixiang; Xing, Junliang; Kuijper, Arjan; Han, Zhenjun; Jiao, Jianbin; Ji, Xiangyang

    2017-12-01

    Tracking multiple persons is a challenging task when persons move in groups and occlude each other. Existing group-based methods have extensively investigated how to make group division more accurately in a tracking-by-detection framework; however, few of them quantify the group dynamics from the perspective of targets' spatial topology or consider the group in a dynamic view. Inspired by the sociological properties of pedestrians, we propose a novel socio-topology model with a topology-energy function to factor the group dynamics of moving persons and groups. In this model, minimizing the topology-energy-variance in a two-level energy form is expected to produce smooth topology transitions, stable group tracking, and accurate target association. To search for the strong minimum in energy variation, we design the discrete group-tracklet jump moves embedded in the gradient descent method, which ensures that the moves reduce the energy variation of group and trajectory alternately in the varying topology dimension. Experimental results on both RGB and RGB-D data sets show the superiority of our proposed model for multiple person tracking in crowd scenes.

  10. TCP (truncated compound Poisson) process for multiplicity distributions in high energy collisions

    Srivastave, P.P.

    1990-01-01

    On using the Poisson distribution truncated at zero for intermediate cluster decay in a compound Poisson process, the authors obtain TCP distribution which describes quite well the multiplicity distributions in high energy collisions. A detailed comparison is made between TCP and NB for UA5 data. The reduced moments up to the fifth agree very well with the observed ones. The TCP curves are narrower than NB at high multiplicity tail, look narrower at very high energy and develop shoulders and oscillations which become increasingly pronounced as the energy grows. At lower energies the distributions, of the data for fixed intervals of rapidity for UA5 data and for the data (at low energy) for e + e - annihilation and pion-proton, proton-proton and muon-proton scattering. A discussion of compound Poisson distribution, expression of reduced moments and Poisson transforms are also given. The TCP curves and curves of the reduced moments for different values of the parameters are also presented

  11. Description of charged particle multiplicity distribution in high energy strong interaction

    Qin Keyu

    1994-01-01

    With the assumption that the probability for n-charged particles production in hadron-hadron collision is Pn and proper choice of 1 , 2 , k and x in Pn, the true multiplicity distribution in full phase space can be described successfully at the centre of mass energy √S GeV. Using the experimental data of non singe-diffractive collisions between proton and antiproton at centre of mass energies of 200 and 900 GeV, the supposition has been examined and confirmed: it is very good to describe the facts. The theoretical bases of supposition were discussed

  12. Prolongation of the deployment and monitoring of a multiple oscillating water column wave energy converter

    Johnson, F.; Chudley, J.; Dai, Y.M.

    2003-07-01

    This report summarises the findings of a project to prolong the sea trials of a multiple oscillating water column wave energy converter (MOWC) device for another 12 months to obtain further data. The objectives of the project include the evaluation of the ability of the MOWC to generate reliable energy to produce electricity, the estimation of the conversion efficiency, and the identification of improvements to increase the conversion efficiency, Details are given of the analysis of the sea trials data, and the performance of the broadband oscillating water column prototype.

  13. Photoneutron multiplicities of preactinide nuclei at energies above the pion threshold

    Arruda-Neto, J.D.T.; Simionatto, S.; Likhachev, V.P.; Garcia, F.; Mesa, J.

    1998-01-01

    The average photoneutron multiplicities anti ν of Au, Ta and 182 W were deduced from their previously measured excitation energies anti E x , from 160 to 250 MeV. A combined analysis of these data and those measured at Saclay up to 140 MeV allowed the extraction of information on anti E x at the ''pure evaporation'' and quasideuteron energy regions. A theoretical approach for the study of anti ν above 140 MeV, which incorporates photopion reabsorption processes by two-body, was proposed, allowing a tentative delineation of the pion mean free path in the nucleus. (orig.)

  14. Multiple Low Energy Long Bone Fractures in the Setting of Rothmund-Thomson Syndrome

    Nicholas Beckmann

    2015-01-01

    Full Text Available Rothmund-Thomson syndrome is a rare autosomal recessive genodermatosis characterized by a poikilodermatous rash starting in infancy as well as various skeletal anomalies, juvenile cataracts, and predisposition to certain cancers. Although Rothmund-Thomson syndrome is associated with diminished bone mineral density in addition to multiple skeletal abnormalities, there are few reports of the association with stress fractures or pathologic fractures in low energy trauma or delayed healing of fractures. Presented is a case of a young adult male with Rothmund-Thomson syndrome presenting with multiple episodes of long bone fractures caused by low energy trauma with one of the fractures exhibiting significantly delayed healing. The patient was also found to have an asymptomatic stress fracture of the lower extremity, another finding of Rothmund-Thomson syndrome rarely reported in the literature. A thorough review of the literature and comprehensive presentation of Rothmund-Thomson syndrome is provided in conjunction with our case.

  15. Energy dependence of the charged multiplicity in deep inelastic scattering at HERA

    Chekanov, S.; Derrick, M.; Magill, S. [Argonne National Laboratory, Argonne, IL (US)] (and others)

    2008-03-15

    The charged multiplicity distributions and the mean charged multiplicity have been investigated in inclusive neutral current deep inelastic ep scattering with the ZEUS detector at HERA, using an integrated luminosity of 38.6 pb{sup -1}. The measurements were performed in the current region of the Breit frame, as well as in the current fragmentation region of the hadronic centre-of-mass frame. The KNO-scaling properties of the data were investigated and the energy dependence was studied using different energy scales. The data are compared to results obtained in e{sup +}e{sup -} collisions and to previous DIS measurements as well as to leading-logarithm parton-shower Monte Carlo predictions. (orig.)

  16. Energy dependence of the charged multiplicity in deep inelastic scattering at HERA

    Chekanov, S.; Derrick, M.; Magill, S.

    2008-03-01

    The charged multiplicity distributions and the mean charged multiplicity have been investigated in inclusive neutral current deep inelastic ep scattering with the ZEUS detector at HERA, using an integrated luminosity of 38.6 pb -1 . The measurements were performed in the current region of the Breit frame, as well as in the current fragmentation region of the hadronic centre-of-mass frame. The KNO-scaling properties of the data were investigated and the energy dependence was studied using different energy scales. The data are compared to results obtained in e + e - collisions and to previous DIS measurements as well as to leading-logarithm parton-shower Monte Carlo predictions. (orig.)

  17. Soft pair excitations and double-log divergences due to carrier interactions in graphene

    Lewandowski, Cyprian; Levitov, L. S.

    2018-03-01

    Interactions between charge carriers in graphene lead to logarithmic renormalization of observables mimicking the behavior known in (3+1)-dimensional quantum electrodynamics (QED). Here we analyze soft electron-hole (e -h ) excitations generated as a result of fast charge dynamics, a direct analog of the signature QED effect—multiple soft photons produced by the QED vacuum shakeup. We show that such excitations are generated in photon absorption, when a photogenerated high-energy e -h pair cascades down in energy and gives rise to multiple soft e -h excitations. This fundamental process is manifested in a double-log divergence in the emission rate of soft pairs and a characteristic power-law divergence in their energy spectrum of the form 1/ω ln(ω/Δ ) . Strong carrier-carrier interactions make pair production a prominent pathway in the photoexcitation cascade.

  18. All orders Boltzmann collision term from the multiple scattering expansion of the self-energy

    Fillion-Gourdeau, F.; Gagnon, J.-S.; Jeon, S.

    2007-01-01

    We summarize our main findings in deriving the Boltzmann collision term from the Kadanoff-Baym relativistic transport equation and the multiple scattering expansion of the self-energy within a quasi-particle approximation. Our collision term is valid to all orders in perturbation theory and contains processes with any number of participating particles. This work completes a program initiated by Carrington and Mrowczynski and developed further by present authors and Weinstock in recent literature

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

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

    2010-01-01

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

  20. Negative binomial multiplicity distributions, a new empirical law for high energy collisions

    Van Hove, L.; Giovannini, A.

    1987-01-01

    For a variety of high energy hadron production reactions, recent experiments have confirmed the findings of the UA5 Collaboration that charged particle multiplicities in central (pseudo) rapidity intervals and in full phase space obey negative binomial (NB) distributions. The authors discuss the meaning of this new empirical law on the basis of new data and they show that they support the interpretation of the NB distributions in terms of a cascading mechanism of hardron production

  1. Enhancing Wind Power Integration through Optimal Use of Flexibility in Multi-Carrier Energy Systems from the Danish Perspective

    Zong, Yi; Awadelrahman, M. A. Ahmed; Wang, Jiawei

    2017-01-01

    Denmark’ goal of being independent of fossil energy sources in 2050 puts forward great demands on all energy subsystems (electricity, heat, gas and transport, etc.) to be operated in a holistic manner. The Danish experience and challenges of wind power integration and the development of district...... heating systems are summarized in this paper. How to optimally use the cross-sectoral flexibility by intelligent control (model predictive control-based) of the key coupling components in an integrated heat and power system including electrical heat pumps in the demand side, and thermal storage...

  2. Performance Analysis of Multiple Wave Energy Converters Placed on a Floating Platform in the Frequency Domain

    Hyebin Lee

    2018-02-01

    Full Text Available Wind-wave hybrid power generation systems have the potential to become a significant source of affordable renewable energy. However, their strong interactions with both wind- and wave-induced forces raise a number of technical challenges for modelling. The present study undertakes a numerical investigation on multi-body hydrodynamic interaction between a wind-wave hybrid floating platform and multiple wave energy converters (WECs in a frequency domain. In addition to the exact responses of the platform and the WECs, the power take-off (PTO mechanism was taken into account for analysis. The coupled hydrodynamic coefficients and wave exciting forces were obtained from WAMIT, the 3D diffraction/radiation solver based on the boundary element method. The overall performance of the multiple WECs is presented and compared with the performance of a single isolated WEC. The analysis showed significant differences in the dynamic responses of the WECs when the multi-body interaction was considered. In addition, the PTO damping effect made a considerable difference to the responses of the WECs. However, the platform response was only minimally affected by PTO damping. With regard to energy capture, the interaction effect of the designed multiple WEC array layout is evaluated. The WEC array configuration showed both constructive and destructive effects in accordance with the incident wave frequency and direction.

  3. Multiple discrete-energy ion features in the inner magnetosphere: 9 February 1998, event

    Y. Ebihara

    2004-04-01

    Full Text Available Multiple discrete-energy ion bands observed by the Polar satellite in the inner magnetosphere on 9 February 1998 were investigated by means of particle simulation with a realistic model of the convection electric field. The multiple bands appeared in the energy vs. L spectrum in the 1–100 keV range when Polar traveled in the heart of the ring current along the outbound and inbound paths. We performed particle tracing, and simulated the energy vs. L spectra of proton fluxes under the dipole magnetic field, the corotation electric field, and the realistic convection electric field model with its parameters depending on the solar wind data. Simulated spectra are shown to agree well with the observed ones. A better agreement is achieved when we rotate the convection electric potential eastward by 2h inMLT and we change the distribution function in time in the near-Earth magnetotail. It is concluded that the multiple bands are likely produced by two processes for this particular event, that is, changes in the convection electric field (for >3keV protons and changes in the distribution function in the near-Earth magnetotail (for <3keV protons. Key words. Magnetospheric physics (energetic particles, trapped; electric field – Space plasma physics (numerical simulation studies

  4. Multiple production of hadrons at high energies in the model of quark-gluon strings

    Kaidalov, A.B.; Ter-Martirosyan, K.A.

    1983-01-01

    Multiple production of hadrons at high energies is considered in the framework of the approach based on a picture of formation and subsequent fission of the quark-gluon strings, corresponding to the Pomeron with αsub(P)(0) > 1. The topological (1/nsub(f))-expansion and the colour-tube model is used. Inclusive cross-sections are expressed in therms of the structure functions and fragmentation functions of quarks and their limiting values are in an agreement with the results of the reggeon theory. It is pointed out that an account of rapidity fluctuations of the ends of the quark-gluon strings, connected to valence or sea quarks, allows one to explain a number of characteristic features of the multiple production of hadrons. In particular the model, which takes into account multipomeron configurations, reproduces the experimentally observed rise of inclusive spectra in a central region and well describes both rapidity and multiplicity distributions of charged particles up to energies of the SPS-collider. It is shown that in this approach the KNO-scaling is only approximately satisfied and the pattern of its violation at energies √ s approximately 10 3 GeV is predicted. Inclusive spectra are investigated in the whole region 0 or approximately 0.1) Feynman scaling is violated only logarithmically and deviations from it are very rsmall at s 3 +10 4 GeV

  5. Solid state cloaking for electrical charge carrier mobility control

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

    2015-07-07

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

  6. Micro-generation dispatch in a smart residential multi-carrier energy system considering demand forecast error

    Sanjari, M.J.; Karami, H.; Gooi, H.B.

    2016-01-01

    Highlights: • Combination of day-ahead and hour-ahead optimizations to design online controller. • Investigating the effect of load forecast error on the system operating cost. • Proposing effective method for hour-ahead resource re-dispatch. • Using the HSS algorithm as a powerful and effective optimization method. • Combining long-term and short-term strategies for optimal dispatch of resources. - Abstract: This paper deals with a residential hybrid thermal/electrical grid-connected home energy system incorporating real data for the load demand. A day-ahead scheduling (DAS) algorithm for dispatching different resources has been developed in previous studies to determine the optimal operation scheduling for the distributed energy resources at each time interval so that the operational cost of a smart house is minimized. However, demand of houses may be changed in each hour and cannot be exactly predicted one day ahead. System complexity caused by nonlinear dynamics of the fuel cell, as a combined heat and power device, and battery charging and discharging time make it difficult to find the optimal operating point of the system by using the optimization algorithms quickly in online applications. In this paper, the demand forecast error is studied and a near-optimal dispatch strategy by using artificial neural network (ANN) is proposed for the residential energy system when the demand changes are known one hour ahead with respect to the predicted day-ahead values. The day-ahead and hour-ahead optimizations are combined and ANN training inputs are adjusted according to the problem such that the economic dispatch of different energy resources can be achieved by the proposed method compared with previous studies. Using the model of the fuel cell extracted from experimental measurement and real data for the load demand makes the results more applicable in real residential energy systems.

  7. Energy Management Strategy Based on Multiple Operating States for a Photovoltaic/Fuel Cell/Energy Storage DC Microgrid

    Ying Han

    2017-01-01

    Full Text Available It is a great challenge for DC microgrids with stochastic renewable sources and volatility loads to achieve better operation performance. This study proposes an energy management strategy based on multiple operating states for a DC microgrid, which is comprised of a photovoltaic (PV array, a proton exchange membrane fuel cell (PEMFC system, and a battery bank. This proposed strategy can share the power properly and keep the bus voltage steady under different operating states (the state of charge (SOC of the battery bank, loading conditions, and PV array output power. In addition, a microgrids test platform is established. In order to verify the effectiveness of the proposed energy management strategy, the strategy is implemented in a hardware system and experimentally tested under different operating states. The experimental results illustrate the good performance of the proposed control strategy for the DC microgrid under different scenarios of power generation and load demand.

  8. Blastocystis Isolates from Patients with Irritable Bowel Syndrome and from Asymptomatic Carriers Exhibit Similar Parasitological Loads, but Significantly Different Generation Times and Genetic Variability across Multiple Subtypes.

    Gie-Bele Vargas-Sanchez

    Full Text Available Blastocystis spp is a common intestinal parasite of humans and animals that has been associated to the etiology of irritable bowel syndrome (IBS; however, some studies have not found this association. Furthermore, many biological features of Blastocystis are little known. The objective of present study was to assess the generation times of Blastocystis cultures, from IBS patients and from asymptomatic carriers. A total of 100 isolates were obtained from 50 IBS patients and from 50 asymptomatic carriers. Up to 50 mg of feces from each participant were cultured in Barret's and in Pavlova's media during 48 h. Initial and final parasitological load were measured by microscopy and by quantitative PCR. Amplicons were purified, sequenced and submitted to GenBank; sequences were analysed for genetic diversity and a Bayesian inference allowed identifying genetic subtypes (ST. Generation times for Blastocystis isolates in both media, based on microscopic measures and molecular assays, were calculated. The clinical symptoms of IBS patients and distribution of Blastocystis ST 1, 2 and 3 in both groups was comparable to previous reports. Interestingly, the group of cases showed scarce mean nucleotide diversity (π as compared to the control group (0.011±0.016 and 0.118±0.177, respectively, whilst high gene flow and small genetic differentiation indexes between different ST were found. Besides, Tajima's D test showed negative values for ST1-ST3. No statistical differences regarding parasitological load between cases and controls in both media, as searched by microscopy and by qPCR, were detected except that parasites grew faster in Barret's than in Pavlova's medium. Interestingly, slow growth of isolates recovered from cases in comparison to those of controls was observed (p<0.05. We propose that generation times of Blastocystis might be easily affected by intestinal environmental changes due to IBS probably because virulent strains with slow growth may be

  9. Future of the gas industry. Energy carriers instead of power source?; Zukunft der Gaswirtschaft. Energietraeger statt Energiequelle?

    Bothe, David; Janssen, Matthias; Riechmann, Christoph [Frontier Economics, Koeln (Germany)

    2017-03-15

    For a long time, natural gas was considered as an ideal bridge technology for the energy transition because of the relatively low CO{sub 2} content. With increasing decarbonisation of electricity generation by renewable energies and the associated political vision of a far-reaching electrification of energy applications, in particular in the heat sector, the gas sector is, however, threatened to be overtaken by the renewables. This creates increasing uncertainty for business models and investments in the natural gas sector itself, but also potentially high macroeconomic costs of the energy transition. It can be shown that such a development is not unavoidable if the gas sector succeeds in using the existing possibilities cleverly. Thereby the continued use of existing gas infrastructure plays a central role. For use of the opportunities, however, a paradigm shift in politics, regulation and natural gas sector is necessary, whose key points are developed in this article. [German] Lange wurde Gas aufgrund des relativ geringen C0{sub 2}-Gehalts als ideale Brueckentechnologie fuer die Energiewende gehandelt. Mit zunehmender Dekarbonisierung der Stromerzeugung durch erneuerbare Energien und der damit verbundenen politischen Vision einer weitreichenden Elektrifizierung von Energieanwendungen insbesondere im Waermesektor droht die Gaswirtschaft allerdings von den Erneuerbaren ueberholt zu werden. Das schafft zunehmende Unsicherheit fuer Geschaeftsmodelle und Investitionen im Gassektor selbst, aber auch potenziell hohe gesamtwirtschaftliche Kosten der Energiewende. Es laesst sich zeigen, dass eine solche Entwicklung nicht unabwendbar ist, wenn es der Gaswirtschaft gelingt, die vorhandenen Moeglichkeiten clever zu nutzen. Dabei spielt der fortgesetzte Gebrauch der bereits vorhandenen Gasinfrastruktur die zentrale Rolle. Zur Nutzung der Chancen ist aber ein Paradigmenwechsel in Politik, Regulierung und Gaswirtschaft notwendig, dessen Eckpunkte in diesem Artikel entwickelt

  10. Energy-Aware Routing in Multiple Domains Software-Defined Networks

    Adriana FERNÁNDEZ-FERNÁNDEZ

    2016-12-01

    Full Text Available The growing energy consumption of communication networks has attracted the attention of the networking researchers in the last decade. In this context, the new architecture of Software-Defined Networks (SDN allows a flexible programmability, suitable for the power-consumption optimization problem. In this paper we address the issue of designing a novel distributed routing algorithm that optimizes the power consumption in large scale SDN with multiple domains. The solution proposed, called DEAR (Distributed Energy-Aware Routing, tackles the problem of minimizing the number of links that can be used to satisfy a given data traffic demand under performance constraints such as control traffic delay and link utilization. To this end, we present a complete formulation of the optimization problem that considers routing requirements for control and data plane communications. Simulation results confirm that the proposed solution enables the achievement of significant energy savings.

  11. Lower Bounds on the Maximum Energy Benefit of Network Coding for Wireless Multiple Unicast

    Matsumoto Ryutaroh

    2010-01-01

    Full Text Available We consider the energy savings that can be obtained by employing network coding instead of plain routing in wireless multiple unicast problems. We establish lower bounds on the benefit of network coding, defined as the maximum of the ratio of the minimum energy required by routing and network coding solutions, where the maximum is over all configurations. It is shown that if coding and routing solutions are using the same transmission range, the benefit in d-dimensional networks is at least . Moreover, it is shown that if the transmission range can be optimized for routing and coding individually, the benefit in 2-dimensional networks is at least 3. Our results imply that codes following a decode-and-recombine strategy are not always optimal regarding energy efficiency.

  12. The Energy Integration Strategies in the Great Caribbean: Multiple Processes and Regional Leadership in Dispute

    María Camila Moncada Guevara

    2016-01-01

    Full Text Available The purpose of this article is to demonstrate, through the paradigm of the complex interdependency that the energy integration processes in the Caribbean during the 21st Century have been multiple, given the integrationist traditions and the strategic regional leadership interests displayed by Venezuela, Mexico and the United States. Therefore, gendas proposed to supply the energy demand in the region deepen the existence of hegemonic projects in dispute. In the first part, political, economic and military aspects of the integration processes in the Caribbean are defined. Then, energy agendas of the 90’s with the Hemisphere Integration Strategy are characterized. Finally, the most recent experience of CARICOM on the matter is analyzed and it is concluded that the region is going through a period of recomposition of the regional powers.

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

    Zhang, Feng; Ikeda, Masao, E-mail: mikeda2013@sinano.ac.cn; Liu, Jianping; Zhang, Shuming [Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences (CAS), Suzhou 215123 (China); Key Lab of Nanodevices and Applications, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences (CAS), Suzhou 215123 (China); Zhou, Kun; Yang, Hui [Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences (CAS), Suzhou 215123 (China); Key Lab of Nanodevices and Applications, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences (CAS), Suzhou 215123 (China); Institute of Semiconductors (CAS), Beijing 100083 (China); Liu, Zongshun [Institute of Semiconductors (CAS), Beijing 100083 (China)

    2015-07-21

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

  14. Multiple exciton generation in quantum dot-based solar cells

    Goodwin, Heather; Jellicoe, Tom C.; Davis, Nathaniel J. L. K.; Böhm, Marcus L.

    2018-01-01

    Multiple exciton generation (MEG) in quantum-confined semiconductors is the process by which multiple bound charge-carrier pairs are generated after absorption of a single high-energy photon. Such charge-carrier multiplication effects have been highlighted as particularly beneficial for solar cells where they have the potential to increase the photocurrent significantly. Indeed, recent research efforts have proved that more than one charge-carrier pair per incident solar photon can be extracted in photovoltaic devices incorporating quantum-confined semiconductors. While these proof-of-concept applications underline the potential of MEG in solar cells, the impact of the carrier multiplication effect on the device performance remains rather low. This review covers recent advancements in the understanding and application of MEG as a photocurrent-enhancing mechanism in quantum dot-based photovoltaics.

  15. Multiple parton scattering in nuclei: heavy quark energy loss and modified fragmentation functions

    Zhang Benwei; Wang, Enke; Wang Xinnian

    2005-01-01

    Multiple scattering, induced radiative energy loss and modified fragmentation functions of a heavy quark in nuclear matter are studied within the framework of generalized factorization in perturbative QCD. Modified heavy quark fragmentation functions and energy loss are derived in detail with illustration of the mass dependencies of the Landau-Pomeranchuk-Migdal interference effects and heavy quark energy loss. Due to the quark mass dependence of the gluon formation time, the nuclear size dependencies of nuclear modification of the heavy quark fragmentation function and heavy quark energy loss are found to change from a linear to a quadratic form when the initial energy and momentum scale are increased relative to the quark mass. The radiative energy loss of the heavy quark is also significantly suppressed due to limited cone of gluon radiation imposed by the mass. Medium modification of the heavy quark fragmentation functions is found to be limited to the large z region due to the form of heavy quark fragmentation functions in vacuum

  16. Multiple regression models for energy use in air-conditioned office buildings in different climates

    Lam, Joseph C.; Wan, Kevin K.W.; Liu Dalong; Tsang, C.L.

    2010-01-01

    An attempt was made to develop multiple regression models for office buildings in the five major climates in China - severe cold, cold, hot summer and cold winter, mild, and hot summer and warm winter. A total of 12 key building design variables were identified through parametric and sensitivity analysis, and considered as inputs in the regression models. The coefficient of determination R 2 varies from 0.89 in Harbin to 0.97 in Kunming, indicating that 89-97% of the variations in annual building energy use can be explained by the changes in the 12 parameters. A pseudo-random number generator based on three simple multiplicative congruential generators was employed to generate random designs for evaluation of the regression models. The difference between regression-predicted and DOE-simulated annual building energy use are largely within 10%. It is envisaged that the regression models developed can be used to estimate the likely energy savings/penalty during the initial design stage when different building schemes and design concepts are being considered.

  17. Scenario and multiple criteria decision analysis for energy and environmental security of military and industrial installations.

    Karvetski, Christopher W; Lambert, James H; Linkov, Igor

    2011-04-01

    Military and industrial facilities need secure and reliable power generation. Grid outages can result in cascading infrastructure failures as well as security breaches and should be avoided. Adding redundancy and increasing reliability can require additional environmental, financial, logistical, and other considerations and resources. Uncertain scenarios consisting of emergent environmental conditions, regulatory changes, growth of regional energy demands, and other concerns result in further complications. Decisions on selecting energy alternatives are made on an ad hoc basis. The present work integrates scenario analysis and multiple criteria decision analysis (MCDA) to identify combinations of impactful emergent conditions and to perform a preliminary benefits analysis of energy and environmental security investments for industrial and military installations. Application of a traditional MCDA approach would require significant stakeholder elicitations under multiple uncertain scenarios. The approach proposed in this study develops and iteratively adjusts a scoring function for investment alternatives to find the scenarios with the most significant impacts on installation security. A robust prioritization of investment alternatives can be achieved by integrating stakeholder preferences and focusing modeling and decision-analytical tools on a few key emergent conditions and scenarios. The approach is described and demonstrated for a campus of several dozen interconnected industrial buildings within a major installation. Copyright © 2010 SETAC.

  18. Technical and economic aspects of thermo-chemical decomposition of biomass in the processes of transformation of it in power-consuming energy/carriers by the use of the concentrated gel of sun radiation, has been considered

    Sultanova, K.D.; Mustafayeva, R.M.; Rzayev, P.F.

    2007-01-01

    Full text: The technical and economic assessment of process of thermo-chemical decomposition of biomass in the processes of transformation of it in power-consuming energy/carriers by the use of the concentrated gel of sun radiation, has been considered

  19. Mathematical Modeling and Optimization of Gaseous Fuel Processing as a Basic Technology for Long-distance Energy Transportation: The Use of Methanol and Dimethyl Ether as Energy Carriers.

    Tyurina, E. A.; Mednikov, A. S.

    2017-11-01

    The paper presents the results of studies on the perspective technologies of natural gas conversion to synthetic liquid fuel (SLF) at energy-technology installations for combined production of SLF and electricity based on their detailed mathematical models. The technologies of the long-distance transport of energy of natural gas from large fields to final consumers are compared in terms of their efficiency. This work was carried out at Melentiev Energy Systems Institute of Siberian Branch of the Russian Academy of Sciences and supported by Russian Science Foundation via grant No 16-19-10174

  20. Multiplicity and energy of neutrons from {sup 233}U(n{sub th},f) fission fragments

    Nishio, Katsuhisa; Kimura, Itsuro; Nakagome, Yoshihiro [Kyoto Univ. (Japan)

    1998-03-01

    The correlation between fission fragments and prompt neutrons from the reaction {sup 233}U(n{sub th},f) was measured with improved accuracy. The results determined the neutron multiplicity and emission energy as a function of fragment mass and total kinetic energy. The average energy as a function of fragment mass followed a nearly symmetric distribution centered about the equal mass-split and formed a remarkable contrast with the saw-tooth distribution of the average neutron multiplicity. The neutron multiplicity from the specified fragment decreases linearly with total kinetic energy, and the slope of multiplicity with kinetic energy had the minimum value at about 130 u. The level density parameter versus mass determined from the neutron data showed a saw-tooth structure with the pronounced minimum at about 128 and generally followed the formula by Gilbert and Cameron, suggesting that the neutron emission process was very much affected by the shell-effect of the fission fragment. (author)

  1. Transverse energy distribution, charged particle multiplicities and spectra in 16O-nucleus collisions

    Sunier, J.W.

    1987-01-01

    The HELIOS (High Energy Lepton and Ion Spectrometer) experiment, installed at the CERN Super Proton Synchrotron, proposes to examine in details the physical properties of a state of high energy created in nuclei by ultra-relativistic nucleus-nucleus collisions. It is generally believed that, at high densities or temperatures, a phase transition to a plasma of quark and gluons will occur. The dynamic of the expansion of such a plasma and its subsequent condensation into a hadron gas should markedly affect the composition and momentum distribution of the emerging particles and photons. The HELIOS experimental setup therefore combines 4π calorimetric coverage with measurements of inclusive particle spectra, two particle correlations, low and high mass lepton pairs and photons. The emphasis is placed on transverse energy flow (E/sub T/) measurements with good energy resolution, and the ability to trigger the acquisition of data in a variety of E/sub T/ ranges, thereby selecting the impact parameter or the violence of the collisions. This short note presents HELIOS results, for the most part still preliminary, on 16 O-nucleus collisions at the incident energies of 60 and 200 GeV per nucleon. The E/sub T/ distributions from Al, Ag and W targets are discussed and compared to the associated charged particle multiplicities from W. Charged particle and (converted) photon spectra measured with the external magnetic spectrometer are compared for 16 O + W and p + W collisions at 200 GeV per nucleon. 5 refs., 7 figs

  2. Charged particle multiplicity distributions in Au-Au collisions at RHIC-BNL energies (BRAHMS Experiment)

    Argintaru, D.; Bearden, I.G.; Beavis, D.

    2002-01-01

    The BRAHMS Experiment (Broad RAnge Hadronic Magnetic Spectrometers) takes place at the Relativistic Heavy Ion Collider (RHIC) from Brookhaven National Laboratory and searches for a transition of matter into a new phase called quark-gluon plasma (QGP), a phase transition that appears in extreme conditions of nuclear matter densities and temperatures. Important signals for this transition are related to dependencies of the charged particle multiplicity distributions on the pseudorapidity range. The charged particle multiplicity distributions in Au-Au collisions at RHIC energies are obtained from the global detector measurements. These detectors are: - An array of Si strip detectors and scintillation tiles placed around the interaction region; they cover the range η < 2 in pseudorapidity, measuring the majority of charged particles; - Two systems of Cerenkov detectors (Beam-Beam Counters) placed both sides of the nominal interaction point at 220 cm and cover the range 3 < η < 4.3 in pseudorapidity. These detectors are used for vertex determination and supply a level zero trigger for the entire experiment; - Zero Degree Calorimeters placed at zero degree with respect to the beam axis, both sides of the vertex, measuring the spectator neutrons from the nuclear reactions. These detectors supplies information about the reaction centrality and could estimate the interaction vertex. The paper presents some results on charged particle multiplicities in different pseudorapidity ranges at different impact parameters. Interesting dependencies of the average charged particle multiplicities on the pseudorapidity range, impact parameters and total available energy in the centre of mass system. Some comparisons with the simulation codes predictions and theoretical model estimations are included, too. (authors)

  3. Observing hot carrier distribution in an n-type epitaxial graphene on a SiC substrate

    Someya, T.; Ishida, Y.; Yoshida, R.; Iimori, T.; Yukawa, R.; Akikubo, K.; Yamamoto, Sh.; Yamamoto, S.; Kanai, T.; Itatani, J.; Komori, F.; Shin, S.; Matsuda, I.; Fukidome, H.; Funakubo, K.; Suemitsu, M.; Yamamoto, T.

    2014-01-01

    Hot carrier dynamics in the Dirac band of n-type epitaxial graphene on a SiC substrate were traced in real time using femtosecond-time-resolved photoemission spectroscopy. The spectral evolution directly reflects the energetically linear density of states superimposed with a Fermi–Dirac distribution. The relaxation time is governed by the internal energy dissipation of electron–electron scattering, and the observed electronic temperature indicates cascade carrier multiplication

  4. Motor carrier evaluation program

    Portsmouth, James

    1992-01-01

    The U.S. Department of Energy-Headquarters (DOE-HQ), Transportation Management Program (TMP) has the overall responsibility to provide a well-managed transportation program for the safe, efficient, and economical transportation of DOE-owned materials. The DOE-TMP has established an excellent safety record in the transportation of hazardous materials including radioactive materials and radioactive wastes. This safety record can be maintained only through continued diligence and sustained effort on the part of the DOE-TMP, its field offices, and the contractors' organizations. Key elements in the DOE'S effective hazardous and radioactive materials shipping program are (1) integrity of packages, (2) strict adherence to regulations and procedures, (3) trained personnel, (4) complete management support, and (5) use of the best commercial carriers. The DOE Motor Carrier Evaluation Program was developed to better define the criteria and methodology needed to identify motor carriers for use in the transportation of Highway Route Controlled Quantities (HRCQ), Truck Load (TL) quantities of radioactive materials, hazardous materials and waste. (author)

  5. Motor carrier evaluation program plan

    Portsmouth, J.H.; Maxwell, J.E.; Boness, G.O.; Rice, L.E.

    1991-04-01

    The US Department of Energy (DOE) Transportation Management Program (TMP) has established a program to assist the DOE field offices and their contractors in evaluating the motor carriers used to transport DOE-owned hazardous and radioactive materials. This program was initiated to provide the DOE field offices with the tools necessary to help ensure, during this period of motor carrier deregulation, that only highly qualified carriers transport radioactive and hazardous commodities for the DOE. This program will assist DOE in maintaining their excellent performance record in the safe transportation of hazardous commodities. The program was also developed in response to public concern surrounding the transportation of hazardous materials. Representatives of other federal agencies, states, and tribal governments, as well as the news media, have expressed concern about the selection and qualification of carriers engaged in the transportation of Highway Route-Controlled Quantities (HRCQ) and Truckload (TL) quantities of radioactive material for the DOE. 8 refs

  6. Influence of Silver and Gold Nanoparticles and Thin Layers on Charge Carrier Generation in InGaN/GaN Multiple Quantum Well Structures and Crystalline Zinc Oxide Films

    Mezdrogina, M. M.; Vinogradov, A. Ya.; Kozhanova, Yu. V.; Levitskii, V. S.

    2018-04-01

    It has been shown that Ag and Au nanoparticles and thin layers influence charge carrier generation in InGaN/GaN multiple quantum well structures and crystalline ZnO films owing to the surface morphology heterogeneity of the semiconductors. When nanoparticles 10 films, the radiation intensity has turned out to grow considerably because of a plasmon resonance with the participation of localized plasmons. The application of Ag or Au layers on the surface of the structures strongly attenuates the radiation. When Ag and Au nanoparticles are applied on crystalline ZnO films obtained by rf magnetron sputtering, the radiation intensity in the short-wavelength part of the spectrum increases insignificantly because of their highly heterogeneous surface morphology.

  7. Universal transport characteristics of multiple topological superconducting wires with large charging energy

    Kashuba, Oleksiy; Trauzettel, Bjoern [Institut fuer Theoretische Physik und Astrophysik, Universitaet Wuerzburg, 97074 Wuerzburg (Germany); Timm, Carsten [Institut fuer Theoretische Physik, TU Dresden, 01062 Dresden (Germany)

    2016-07-01

    The system with multiple Majorana states coupled to the normal lead can potentially support the interaction between Majorana fermions and electrons. Such system can be implemented by several floating topological superconducting wires with large charging energy asymmetrically coupled to two normal leads. The analysis of the renormalization flow shows that there is a single fixed point - the strong coupling limit of isotropic antiferromagnetic Kondo model. The topological Kondo-like interaction leads also to the selective renormalization of the tunneling coefficients, strongly enhancing one component and suppressing others. Thus, charging energy crucially changes the transport properties of the system leading to the universal single-channel conductance independently from the values of the initial leads-wires coupling.

  8. An energy efficient multiple mobile sinks based routing algorithm for wireless sensor networks

    Zhong, Peijun; Ruan, Feng

    2018-03-01

    With the fast development of wireless sensor networks (WSNs), more and more energy efficient routing algorithms have been proposed. However, one of the research challenges is how to alleviate the hot spot problem since nodes close to static sink (or base station) tend to die earlier than other sensors. The introduction of mobile sink node can effectively alleviate this problem since sink node can move along certain trajectories, causing hot spot nodes more evenly distributed. In this paper, we mainly study the energy efficient routing method with multiple mobile sinks support. We divide the whole network into several clusters and study the influence of mobile sink number on network lifetime. Simulation results show that the best network performance appears when mobile sink number is about 3 under our simulation environment.

  9. Multiplicity fluctuations of identified hadrons in p+p interactions at SPS energies

    Maćkowiak-Pawłowska, Maja

    2014-01-01

    Study of energy and system size fluctuations of identified hadrons is one of the key goals of NA61/SHINE at the CERN SPS. Results may allow to discover the critical point (CP) of strongly interacting matter as well as to uncover properties of the onset of deconfinement (OD). But fluctuations exhibit numerous other sources starting from most basic ones like volume effects and conservation laws. NA49 seems to observe fluctuations related to CP in collisions of medium size nuclei at top SPS energy. However, this result will remain inconclusive until systematic data on energy and system size dependence will be available. Moreover, fluctuations in p+p as well as in Pb+Pb interactions should be better understood. In this contribution results on multiplicity fluctuations of identified hadrons in p+p interactions at the CERN SPS energies will be presented. The NA61 data will be compared with the corresponding results from central Pb+Pb collisions of NA49 in the common acceptance region of both experiments. Moreover, ...

  10. Energy Band Gap, Intrinsic Carrier Concentration and Fermi Level of CdTe Bulk Crystal between 304 K and 1067 K

    Su, Ching-Hua

    2007-01-01

    Optical transmission measurements were performed on CdTe bulk single crystal. It was found that when a sliced and polished CdTe wafer was used, a white film started to develop when the sample was heated above 530 K and the sample became opaque. Therefore, a bulk crystal of CdTe was first grown in the window area by physical vapor transport; the optical transmission was then measured and from which the energy band gap was derived between 304 and 1067 K. The band gaps of CdTe can be fit well as a function of temperature using the Varshini expression: Eg (e V) = 1.5860 - 5.9117xl0(exp -4) T(sup 2)/(T + 160). Using the band gap data, the high temperature electron-hole equilibrium was calculated numerically by assuming the Kane's conduction band structure and a heavy-hole parabolic valance band. The calculated intrinsic carrier concentrations agree well with the experimental data reported previously. The calculated intrinsic Fermi levels between 270 and 1200 K were also presented.

  11. Multiple scattering theory and applications for intermediate energy reactions of nuclei

    Ludeking, L.D.

    1979-01-01

    Interactions of two composite clusters are treated in a multiple scattering framework whereby many-particle operators are decomposed into a systematic and finite series such that there is an ordered sequestering according to particle rank. Thus, an N-body operator is written as the superposition of all distinct groupings of interactions that occur between particle pairs, triplets, quartets, etc., such that all groupings contain at least one particle from each of the composite systems. It is demonstrated how the transition operator, a reaction operator, and an optical potential may be described in this context. The general structure of such decompositions is shown, and the connection to the standard multiple-scattering prescriptions, delineated. The direct reaction amplitude for stripping and pickup is described, and the two potential formula of Gell-Mann and Goldberger is derived. The multiple scattering formalism for direct reactions is constructed in the eikonal approximation. The sensitivity of the transition cross section to the target density and nucleon-nucleon density correlations are examined in this framework. The limitations of the zero-range approximation to the deuteron vertex function are examined by comparison with the finite-range vertex function at a range of energies. 25 figures, 5 tables

  12. Profile of Cognitive Ability and Multiple Intelligence of Vocational Students in Application of Electric Energy Conservation

    Kurniawan, A.; Rustaman, N. Y.; Kaniawati, I.; Hasanah, L.

    2017-09-01

    The purpose of this study is to obtain a profile picture of cognitive ability and multiple intelligence of students on physics learning activities in relation to the discourse of conservation of electrical energy. Research activities are conducted in the even semester of the 2015/2016 school year. The subjects of the study were the students of class XI (36 students) in one of the state vocational schools in Bandung consisting of one class chosen at random (cluster random sampling). Research data in the form of cognitive ability test results and multiple intelligences are analyzed descriptively and qualitatively. Research data is then analyzed and compared with predetermined success indicators. The results showed that the cognitive abilities profile of students in vocational schools in Bandung is still low. This can be seen from the average score of cognitive ability of students in remember (C1) of 57.75, understanding (C2) of 53.50, applying (C3) of 43.75, and analyzing (C4) of 37.75. The multiple intelligence profiles indicate frequency of linguistic intelligence number 9 students, musical intelligence 3 students, logical mathematical intelligence 13 students, spatial intelligence 7 students, kinesthetic intelligence 5 students, intrapersonal intelligence 7 students, interpersonal intelligence 6 students, and naturalistic intelligence 5 students.

  13. FireProt: Energy- and Evolution-Based Computational Design of Thermostable Multiple-Point Mutants.

    Bednar, David; Beerens, Koen; Sebestova, Eva; Bendl, Jaroslav; Khare, Sagar; Chaloupkova, Radka; Prokop, Zbynek; Brezovsky, Jan; Baker, David; Damborsky, Jiri

    2015-11-01

    There is great interest in increasing proteins' stability to enhance their utility as biocatalysts, therapeutics, diagnostics and nanomaterials. Directed evolution is a powerful, but experimentally strenuous approach. Computational methods offer attractive alternatives. However, due to the limited reliability of predictions and potentially antagonistic effects of substitutions, only single-point mutations are usually predicted in silico, experimentally verified and then recombined in multiple-point mutants. Thus, substantial screening is still required. Here we present FireProt, a robust computational strategy for predicting highly stable multiple-point mutants that combines energy- and evolution-based approaches with smart filtering to identify additive stabilizing mutations. FireProt's reliability and applicability was demonstrated by validating its predictions against 656 mutations from the ProTherm database. We demonstrate that thermostability of the model enzymes haloalkane dehalogenase DhaA and γ-hexachlorocyclohexane dehydrochlorinase LinA can be substantially increased (ΔTm = 24°C and 21°C) by constructing and characterizing only a handful of multiple-point mutants. FireProt can be applied to any protein for which a tertiary structure and homologous sequences are available, and will facilitate the rapid development of robust proteins for biomedical and biotechnological applications.

  14. FireProt: Energy- and Evolution-Based Computational Design of Thermostable Multiple-Point Mutants.

    David Bednar

    2015-11-01

    Full Text Available There is great interest in increasing proteins' stability to enhance their utility as biocatalysts, therapeutics, diagnostics and nanomaterials. Directed evolution is a powerful, but experimentally strenuous approach. Computational methods offer attractive alternatives. However, due to the limited reliability of predictions and potentially antagonistic effects of substitutions, only single-point mutations are usually predicted in silico, experimentally verified and then recombined in multiple-point mutants. Thus, substantial screening is still required. Here we present FireProt, a robust computational strategy for predicting highly stable multiple-point mutants that combines energy- and evolution-based approaches with smart filtering to identify additive stabilizing mutations. FireProt's reliability and applicability was demonstrated by validating its predictions against 656 mutations from the ProTherm database. We demonstrate that thermostability of the model enzymes haloalkane dehalogenase DhaA and γ-hexachlorocyclohexane dehydrochlorinase LinA can be substantially increased (ΔTm = 24°C and 21°C by constructing and characterizing only a handful of multiple-point mutants. FireProt can be applied to any protein for which a tertiary structure and homologous sequences are available, and will facilitate the rapid development of robust proteins for biomedical and biotechnological applications.

  15. Direct integration multiple collision integral transport analysis method for high energy fusion neutronics

    Koch, K.R.

    1985-01-01

    A new analysis method specially suited for the inherent difficulties of fusion neutronics was developed to provide detailed studies of the fusion neutron transport physics. These studies should provide a better understanding of the limitations and accuracies of typical fusion neutronics calculations. The new analysis method is based on the direct integration of the integral form of the neutron transport equation and employs a continuous energy formulation with the exact treatment of the energy angle kinematics of the scattering process. In addition, the overall solution is analyzed in terms of uncollided, once-collided, and multi-collided solution components based on a multiple collision treatment. Furthermore, the numerical evaluations of integrals use quadrature schemes that are based on the actual dependencies exhibited in the integrands. The new DITRAN computer code was developed on the Cyber 205 vector supercomputer to implement this direct integration multiple-collision fusion neutronics analysis. Three representative fusion reactor models were devised and the solutions to these problems were studied to provide suitable choices for the numerical quadrature orders as well as the discretized solution grid and to understand the limitations of the new analysis method. As further verification and as a first step in assessing the accuracy of existing fusion-neutronics calculations, solutions obtained using the new analysis method were compared to typical multigroup discrete ordinates calculations

  16. Scaling of charged particle multiplicity in Pb-Pb collisions at SPS energies

    Abreu, M C; Alexa, C; Arnaldi, R; Ataian, M R; Baglin, C; Baldit, A; Bedjidian, Marc; Beolè, S; Boldea, V; Bordalo, P; Borges, G; Bussière, A; Capelli, L; Castanier, C; Castor, J I; Chaurand, B; Chevrot, I; Cheynis, B; Chiavassa, E; Cicalò, C; Claudino, T; Comets, M P; Constans, N; Constantinescu, S; Cortese, P; De Falco, A; De Marco, N; Dellacasa, G; Devaux, A; Dita, S; Drapier, O; Ducroux, L; Espagnon, B; Fargeix, J; Force, P; Gallio, M; Gavrilov, Yu K; Gerschel, C; Giubellino, P; Golubeva, M B; Gonin, M; Grigorian, A A; Grigorian, S; Grossiord, J Y; Guber, F F; Guichard, A; Gulkanian, H R; Hakobyan, R S; Haroutunian, R; Idzik, M; Jouan, D; Karavitcheva, T L; Kluberg, L; Kurepin, A B; Le Bornec, Y; Lourenço, C; Macciotta, P; MacCormick, M; Marzari-Chiesa, A; Masera, M; Masoni, A; Monteno, M; Musso, A; Petiau, P; Piccotti, A; Pizzi, J R; Prado da Silva, W L; Prino, F; Puddu, G; Quintans, C; Ramello, L; Ramos, S; Rato-Mendes, P; Riccati, L; Romana, A; Santos, H; Saturnini, P; Scalas, E; Scomparin, E; Serci, S; Shahoyan, R; Sigaudo, F; Silva, S; Sitta, M; Sonderegger, P; Tarrago, X; Topilskaya, N S; Usai, G L; Vercellin, Ermanno; Villatte, L; Willis, N

    2002-01-01

    The charged particle multiplicity distribution $dN_{ch}/d\\eta$ has been measured by the NA50 experiment in Pb--Pb collisions at the CERN SPS. Measurements were done at incident energies of 40 and 158 GeV per nucleon over a broad impact parameter range. The multiplicity distributions are studied as a function of centrality using the number of participating nucleons ($N_{part}$), or the number of binary nucleon--nucleon collisions ($N_{coll}$). Their values at midrapidity exhibit a power law scaling behaviour given by $N_{part}^{1.00}$ and $N_{coll}^{0.75}$ at 158 GeV. Compatible results are found for the scaling behaviour at 40 GeV. The width of the $dN_{ch}/d\\eta$ distributions is larger at 158 than at 40 GeV/nucleon and decreases slightly with centrality at both energies. Our results are compared to similar studies performed by other experiments both at the CERN SPS and at RHIC.}

  17. Event-by-event gluon multiplicity, energy density, and eccentricities in ultrarelativistic heavy-ion collisions

    Schenke, Björn; Tribedy, Prithwish; Venugopalan, Raju

    2012-09-01

    The event-by-event multiplicity distribution, the energy densities and energy density weighted eccentricity moments ɛn (up to n=6) at early times in heavy-ion collisions at both the BNL Relativistic Heavy Ion Collider (RHIC) (s=200GeV) and the CERN Large Hardron Collider (LHC) (s=2.76TeV) are computed in the IP-Glasma model. This framework combines the impact parameter dependent saturation model (IP-Sat) for nucleon parton distributions (constrained by HERA deeply inelastic scattering data) with an event-by-event classical Yang-Mills description of early-time gluon fields in heavy-ion collisions. The model produces multiplicity distributions that are convolutions of negative binomial distributions without further assumptions or parameters. In the limit of large dense systems, the n-particle gluon distribution predicted by the Glasma-flux tube model is demonstrated to be nonperturbatively robust. In the general case, the effect of additional geometrical fluctuations is quantified. The eccentricity moments are compared to the MC-KLN model; a noteworthy feature is that fluctuation dominated odd moments are consistently larger than in the MC-KLN model.

  18. Inert carriers for column extraction chromatography

    Katykhin, G.S.

    1978-01-01

    Inert carriers used in column extraction chromatography are reviewed. Such carriers are devided into two large groups: hydrophilic carriers which possess high surface energy and are well wetted only with strongly polar liquids (kieselguhrs, silica gels, glasses, cellulose, Al 2 O 3 ) and water-repellent carriers which possess low surface energy and are well wetted with various organic solvents (polyethylene, polytetrafluorethylene polytrifluorochlorethylene). Properties of various carriers are presented: structure, chemical and radiation stability, adsorption properties, extracting agent capacity. The effect of structure and sizes of particles on the efficiency of chromatography columns is considered. Ways of immovable phase deposition on the carrier and the latter's regeneration. Peculiarities of column packing for preparative and continuous chromatography are discussed

  19. Simulation of hadron multiple production by cosmic-ray protons in the incident energy region of 1015 eV

    Takatsuka, Ichiro

    1984-01-01

    The simulation studies of the unusual cosmic ray families found by the experiment at Mt. Chacaltaya were performed. Those families have a larger number of hadrons than the normal families, or are the families with big transverse extension. The former is called Centauro or Mini-centauro, and the latter is called Binocular and Chiron. In the first simulation, the process was calculated, in which the Lorentz transformation of π-meson multiple production (C-jet) in the energy region of 10 14 eV was made, and the jet with raised energy was combined, and the families were formed. The second simulation was made for the energy region more than 300 TeV, in which the nucleon-antinucleon multiple production with large transverse momentum and the B particle multiple production with larger transverse momentum were assumed. The data used were the C-jet data observed at Mt. Chacaltaya. For the simulation, all the primary particles were considered to be protons. The results of the present simulation study showed that the families with strong hadron components observed at Mt. Chacaltaya might be the new type hadron multiple production such as nucleon-antinucleon multiple production or B-particle multiple production. The total energy of all the families increased with the energy of the primary particles. There are a few families having the same extent of energy and spread as the Chiron. (Kato, T.)

  20. Levels of high energy cottonseed meal in multiple supplements for grazing cattle: performance and economic evaluation

    Joanis Tilemahos Zervoudakis

    2015-10-01

    Full Text Available The objective was to evaluate the substitution levels of protein from soybean meal by high energy cottonseed (CS meal in multiple supplements for beef cattle grazing in the dry season on the average daily gain (ADG and economic viability. Twenty Nellore steers with initial body weight of 351.25±35.38 kg and average initial age of 24±0.8 months were used, divided into four paddocks of Brachiaria brizantha cv. Marandu with 1.6 ha each incompletely randomized design with four animals and five supplements to assess the following supplements: 0CS, 25CS and 50CS corresponding to the level of 0,25 and 50% high energy cottonseed meal to replace the meal soybean, provided the amount of 2 kg/animal/day, which were compared to mineral mixture (MM. The supplement 25CS provided higher (P<0.0001 ADG (0.75kg/animal/day-1 compared to supplement 50CS (0.60kg/animal/day-1. The ADG of animals supplemented with 0CS (0.53kg/animal/day-1 did not differ (P<0.0001 of the ADG of the bulls receiving supplementation with 25CS (0.75k /animal/day-1 and 50CS (0,60kg / animal / day-1. The 25CS supplement showed a higher economic return on invested capital in the period. The use of cottonseed meal high energy level of 25% replacement of soybean meal in multiple supplements provided greater weight gain of cattle and improved economic viability. 

  1. Stepwise multiple regression method of greenhouse gas emission modeling in the energy sector in Poland.

    Kolasa-Wiecek, Alicja

    2015-04-01

    The energy sector in Poland is the source of 81% of greenhouse gas (GHG) emissions. Poland, among other European Union countries, occupies a leading position with regard to coal consumption. Polish energy sector actively participates in efforts to reduce GHG emissions to the atmosphere, through a gradual decrease of the share of coal in the fuel mix and development of renewable energy sources. All evidence which completes the knowledge about issues related to GHG emissions is a valuable source of information. The article presents the results of modeling of GHG emissions which are generated by the energy sector in Poland. For a better understanding of the quantitative relationship between total consumption of primary energy and greenhouse gas emission, multiple stepwise regression model was applied. The modeling results of CO2 emissions demonstrate a high relationship (0.97) with the hard coal consumption variable. Adjustment coefficient of the model to actual data is high and equal to 95%. The backward step regression model, in the case of CH4 emission, indicated the presence of hard coal (0.66), peat and fuel wood (0.34), solid waste fuels, as well as other sources (-0.64) as the most important variables. The adjusted coefficient is suitable and equals R2=0.90. For N2O emission modeling the obtained coefficient of determination is low and equal to 43%. A significant variable influencing the amount of N2O emission is the peat and wood fuel consumption. Copyright © 2015. Published by Elsevier B.V.

  2. Multiple sample setup for testing the hydrothermal stability of adsorbents in thermal energy storage applications

    Fischer, Fabian; Laevemann, Eberhard

    2015-01-01

    Thermal energy storage based on adsorption and desorption of water on an adsorbent can achieve high energy storage densities. Many adsorbents lose adsorption capacity when operated under unfavourable hydrothermal conditions during adsorption and desorption. The stability of an adsorbent against stressing hydrothermal conditions is a key issue for its usability in adsorption thermal energy storage. We built an experimental setup that simultaneously controls the hydrothermal conditions of 16 samples arranged in a matrix of four temperatures and four water vapour pressures. This setup allows the testing of potential adsorbents between temperatures of 50 °C and 350 °C and water vapour pressures of up to 32 kPa. A measurement procedure that allows the detection of the hydrothermal stability of an adsorbent after defined time spans has been designed. We verified the functionality of the multiple sample measurements with a microporous adsorbent, a zeolite NaMSX. The hydrothermal stability of this zeolite is tested by water uptake measurements. A standard deviation lower than 1% of the 16 samples for detecting the hydrothermal stability enables setting different conditions in each sample cell. Further, we compared the water uptake measurements by measuring their adsorption isotherms with the volumetric device BELSORP Aqua 3 from Bel Japan. (paper)

  3. Physics and Its Multiple Roles in the International Atomic Energy Agency

    Massey, Charles D.

    2017-01-01

    The IAEA is the world's centre for cooperation in the nuclear field. It was set up as the world's ``Atoms for Peace'' organization in 1957 within the United Nations family. The Agency works with its Member States and multiple partners worldwide to promote the safe, secure and peaceful use of nuclear technologies. Three main areas of work underpin the IAEA's mission: Safety and Security, Science and Technology, and Safeguards and Verification. To carry out its mission, the Agency is authorized to encourage and assist research on, and development and practical application of, atomic energy for peaceful uses throughout the world; foster the exchange of scientific and technical information on peaceful uses of atomic energy; and encourage the exchange of training of scientists and experts in the field of peaceful uses of atomic energy. Nowadays, nuclear physics and nuclear technology are applied in a great variety of social areas, such as power production, medical diagnosis and therapies, environmental protection, security control, material tests, food processing, waste treatments, agriculture and artifacts analysis. This presentation will cover the role and practical application of physics at the IAEA, and, in particular, focus on the role physics has, and will play, in nuclear security.

  4. Z/γ{sup ∗} plus multiple hard jets in high energy collisions

    Andersen, Jeppe R. [Institute for Particle Physics Phenomenology, University of Durham,South Road, Durham DH1 3LE (United Kingdom); Medley, Jack J.; Smillie, Jennifer M. [Higgs Centre for Theoretical Physics, University of Edinburgh,Peter Guthrie Tait Road, Edinburgh EH9 3FD (United Kingdom)

    2016-05-23

    We present a description of the production of di-lepton pair production (through Z boson and virtual photon) in association with at least two jets. This calculation adds to the fixed-order accuracy the dominant logarithms in the limit of large partonic centre-of-mass energy to all orders in the strong coupling α{sub s}. This is achieved within the framework of High Energy Jets. This calculation is made possible by extending the high energy treatment to take into account the multiple t-channel exchanges arising from Z and γ{sup ∗}-emissions off several quark lines. The correct description of the interference effects from the various t-channel exchanges requires an extension of the subtraction terms in the all-order calculation. We describe this construction and compare the resulting predictions to a number of recent analyses of LHC data. The description of a wide range of observables is good, and, as expected, stands out from other approaches in particular in the regions of large dijet invariant mass and large dijet rapidity spans.

  5. Multiple Input Energy Harvesting Systems for Autonomous IoT End-Nodes

    Johan J. Estrada-López

    2018-03-01

    Full Text Available The Internet-of-Things (IoT paradigm is under constant development and is being enabled by the latest research work from both industrial and academic communities. Among the many contributions in such diverse areas as sensor manufacturing, network protocols, and wireless communications, energy harvesting techniques stand out as a key enabling technology for the realization of batteryless IoT end-node systems. In this paper, we give an overview of the recent developments in circuit design for ultra-low power management units (PMUs, focusing mainly in the architectures and techniques required for energy harvesting from multiple heterogeneous sources. The paper starts by discussing a general structure for IoT end-nodes and the main characteristics of PMUs for energy harvesting. Then, an overview is given of different published works for multisource power harvesting, observing their main advantages and disadvantages and comparing their performance. Finally, some open areas of research in multisource harvesting are observed and relevant conclusions are given.

  6. Analysis on energy saving potential of integrated supermarket HVAC and refrigeration systems using multiple subcoolers

    Yang, Liang [Institute of Refrigeration and Cryogenics, Shanghai Jiaotong University, Shanghai 200240 (China); China R and D Center, Carrier Corporation, No. 3239 Shen Jiang Road, Shanghai 201206 (China); Zhang, Chun-Lu [China R and D Center, Carrier Corporation, No. 3239 Shen Jiang Road, Shanghai 201206 (China)

    2010-02-15

    The paper presents a model-based analysis on the energy saving potential of supermarket HVAC (heating, ventilating, and air-conditioning) and refrigeration systems using multiple subcoolers among the high-temperature HVAC system, the medium-temperature refrigeration system, and the low-temperature refrigeration system. The principle of energy reduction is to have the higher COP (coefficient of performance) system generate more cooling capacity to increase the cooling capacity or reduce the power consumption of the lower COP system. The subcooler could be placed between the medium-temperature and low-temperature systems, between the high-temperature and medium-temperature systems, and between the high-temperature and low-temperature systems. All integration scenarios of adding one, two and three subcoolers have been investigated. The energy saving potential varies with the load ratio between high-, medium- and low-temperature systems, COP of three systems, and the ''on-off'' duty time of HVAC system. The optimal sequence of adding subcoolers is also proposed. (author)

  7. The effect of folic acid, protein energy and multiple micronutrient supplements in pregnancy on stillbirths

    Bhutta Zulfiqar A

    2011-04-01

    Full Text Available Abstract Background Pregnancy is a state of increased requirement of macro- and micronutrients, and malnourishment or inadequate dietary intake before and during pregnancy, can lead to adverse perinatal outcomes including stillbirths. Many nutritional interventions have been proposed during pregnancy according to the nutritional status of the mother and baseline risk factors for different gestational disorders. In this paper, we have reviewed three nutritional interventions including peri-conceptional folic acid supplementation, balanced protein energy supplementation and multiple micronutrients supplementation during pregnancy. This paper is a part of a series to estimate the effect of interventions on stillbirths for input to Live Saved Tool (LiST model. Methods We systematically reviewed all published literature to identify studies evaluating effectiveness of peri-conceptional folic acid supplementation in reducing neural tube defects (NTD, related stillbirths and balanced protein energy and multiple micronutrients supplementation during pregnancy in reducing all-cause stillbirths. The primary outcome was stillbirths. Meta-analyses were generated where data were available from more than one study. Recommendations were made for the Lives Saved Tool (LiST model based on rules developed by the Child Health Epidemiology Reference Group (CHERG. Results There were 18 studies that addressed peri-conceptional folic acid supplementation for prevention of neural tube defects (NTDs. Out of these, 7 studies addressed folic acid supplementation while 11 studies evaluated effect of folic acid fortification. Pooled results from 11 fortification studies showed that it reduces primary incidence of NTDs by 41 % [Relative risk (RR 0.59; 95 % confidence interval (CI 0.52-0.68]. This estimate has been recommended for inclusion in the LiST as proxy for reduction in stillbirths. Pooled results from three studies considered to be of low quality and suggest that

  8. Uncertainty analysis of the Operational Simplified Surface Energy Balance (SSEBop) model at multiple flux tower sites

    Chen, Mingshi; Senay, Gabriel B.; Singh, Ramesh K.; Verdin, James P.

    2016-01-01

    Evapotranspiration (ET) is an important component of the water cycle – ET from the land surface returns approximately 60% of the global precipitation back to the atmosphere. ET also plays an important role in energy transport among the biosphere, atmosphere, and hydrosphere. Current regional to global and daily to annual ET estimation relies mainly on surface energy balance (SEB) ET models or statistical and empirical methods driven by remote sensing data and various climatological databases. These models have uncertainties due to inevitable input errors, poorly defined parameters, and inadequate model structures. The eddy covariance measurements on water, energy, and carbon fluxes at the AmeriFlux tower sites provide an opportunity to assess the ET modeling uncertainties. In this study, we focused on uncertainty analysis of the Operational Simplified Surface Energy Balance (SSEBop) model for ET estimation at multiple AmeriFlux tower sites with diverse land cover characteristics and climatic conditions. The 8-day composite 1-km MODerate resolution Imaging Spectroradiometer (MODIS) land surface temperature (LST) was used as input land surface temperature for the SSEBop algorithms. The other input data were taken from the AmeriFlux database. Results of statistical analysis indicated that the SSEBop model performed well in estimating ET with an R2 of 0.86 between estimated ET and eddy covariance measurements at 42 AmeriFlux tower sites during 2001–2007. It was encouraging to see that the best performance was observed for croplands, where R2 was 0.92 with a root mean square error of 13 mm/month. The uncertainties or random errors from input variables and parameters of the SSEBop model led to monthly ET estimates with relative errors less than 20% across multiple flux tower sites distributed across different biomes. This uncertainty of the SSEBop model lies within the error range of other SEB models, suggesting systematic error or bias of the SSEBop model is within

  9. Multiple energy supply risks, optimal reserves, and optimal domestic production capacities

    Zweifel, P.; Ferrari, M.

    1992-01-01

    This study starts from the observation that today's Western trading nations are exposed to multiple risks of energy supplies, e.g. simultaneous shortage of oil and electricity supplies. To cope with these risks, oil can be stockpiled as well as domestic capacity for power production built up. Adopting the viewpoint of a policy maker who aims at minimizing the expected cost of security of supply, optimal simultaneous adjustments of oil stocks and electric production capacities to exogenous changes such as economic growth are derived. Against this benchmark, one-dimensional rules such as 'oil reserves for 90 days' turn out to be not only suboptimal but also to foster adjustments that exacerbate suboptimality. 9 refs., 1 tabs

  10. Energy efficient design for MIMO two-way AF multiple relay networks

    Alsharoa, Ahmad M.

    2014-04-01

    This paper studies the energy efficient transmission and the power allocation problem for multiple two-way relay networks equipped with multi-input multi-output antennas where each relay employs an amplify-and-forward strategy. The goal is to minimize the total power consumption without degrading the quality of service of the terminals. In our analysis, we start by deriving closed-form expressions of the optimal powers allocated to terminals. We then employ a strong optimization tool based on the particle swarm optimization technique to find the optimal power allocated at each relay antenna. Our numerical results illustrate the performance of the proposed scheme and show that it achieves a sub-optimal solution very close to the optimal one.

  11. Adaptive Control Design for Autonomous Operation of Multiple Energy Storage Systems in Power Smoothing Applications

    Meng, Lexuan; Dragicevic, Tomislav; Guerrero, Josep M.

    2018-01-01

    -pass-filter (HPF) structure. It generates the power reference according to the fluctuating power and provides a stabilization effect. The power and energy supplied by ESS are majorly configured by the cut-off frequency and gain of the HPF. Considering the operational limits on ESS state-of-charge (SoC), this paper...... proposes an adaptive cut-off frequency design method to realize communication-less and autonomous operation of a system with multiple distributed ESS. The experimental results demonstrate that the SoCs of all ESS units are kept within safe margins, while the SoC level and power of the paralleled units...... converge to the final state, providing a natural plug-and-play function....

  12. Forward-backward multiplicity fluctuation and longitudinal harmonics in high-energy nuclear collisions

    Jia, Jiangyong; Radhakrishnan, Sooraj; Zhou, Mingliang; Huo, Peng

    2016-12-01

    Forward-backward (FB) multiplicity fluctuation in high-energy nuclear collisions can be quantified by two-particle pseudo-rapidity correlation function and its expansion into Legendre polynomials. The corresponding coefficients represent different fluctuation modes in longitudinal direction. The leading term corresponds to the asymmetry of numbers of the participants from the two colliding nuclei. This method is tested in events generated from AMPT and HIJING model. The an signal are found to be strongly dampened in AMPT than in HIJIGN, due to weaker short-range correlaitons and final-state effects in AMPT. Two-particle correlation also reveals an intresting shallow minimum around Δη ≈ 0 in AMPT events, which is absent in HIJING results. The method opens a new avenue to elucidate the particle production mechanism and early time dynamics in heavy-ion collisions.

  13. The linear attenuation coefficients as features of multiple energy CT image classification

    Homem, M.R.P.; Mascarenhas, N.D.A.; Cruvinel, P.E.

    2000-01-01

    We present in this paper an analysis of the linear attenuation coefficients as useful features of single and multiple energy CT images with the use of statistical pattern classification tools. We analyzed four CT images through two pointwise classifiers (the first classifier is based on the maximum-likelihood criterion and the second classifier is based on the k-means clustering algorithm) and one contextual Bayesian classifier (ICM algorithm - Iterated Conditional Modes) using an a priori Potts-Strauss model. A feature extraction procedure using the Jeffries-Matusita (J-M) distance and the Karhunen-Loeve transformation was also performed. Both the classification and the feature selection procedures were found to be in agreement with the predicted discrimination given by the separation of the linear attenuation coefficient curves for different materials

  14. Two-particle one-hole multiple-scattering contribution to 17O energies using an energy-dependent reaction matrix

    Bando, H.; Krenciglowa, E.M.

    1976-01-01

    The role of 2p1h correlations in 17 O is studied within a multiple-scattering formalism. An accurate, energy-dependent reaction matrix with orthogonalized plane-wave intermediate states is used to assess the relative importance of particle-particle and particle-hole correlations in the 17 O energies. The effect of energy dependence of the reaction matrix is closely examined. (Auth.)

  15. Multiple Sources of Pressure for Change: The Barroso Commission and Energy Policy for an Enlarged EU

    Jan Frederik Braun

    2009-11-01

    Full Text Available This article presents a preliminary analysis of how and why the role, work and status of the European Commission are changing in an enlarged European Union. It does so by focusing on multiple sources of pressure for change. These include: enlargement, new modes of governance, administrative reforms and changed leadership under Barroso. Combined, though not interlinked, these multiple sources of pressure are evidence of the increasing difficulty for the Commission to design and propose Community-wide answers to complex challenges in a more diverse Union. For this reason, the Commission under Barroso relies less on its traditional monopoly power to propose formal legislation and more on non-traditional modes of policy-making. Energy policy, especially its external dimension, constitutes a policy field that has been affected by enlargement, i.e. characterised by an increasing heterogeneity of needs and preferences among the member states. Not only does it resists Community-wide answers, it also allows the Commission, as an agent, to make use of bureaucratic drifts, i.e. exploit its strategic position in the EU’s governance system and use of a range of formal and informal resources of expertise. To deliver sustainable European added value to this complex policy area, however, the Commission must focus more on pragmatic policy results by making smart use of the EU’s increasing asymmetry, diversity and subsidiarity in a bottom-up approach. A non-legislative approach can serve as a modus vivendi to keep the momentum going in the Union’s difficult struggle to establish a workable energy regime.

  16. Localized subsurface modification of materials using micro-low-energy multiple ion beamlets

    Abhishek Chowdhury

    2011-12-01

    Full Text Available Generation of focused multiple ion beamlets from an intense microwave plasma source is investigated for the creation of localized subsurface modification of materials. Unlike conventional single element focused ion beam (FIB systems, the plasma source is capable of providing ion beams of multiple elements. Two types of plasma electrodes (PE are employed, one with a honeycomb structure with notched apertures and another with a 5×5 array of through apertures, both attached to the plasma source and are capable of generating focused ion beamlets (50 - 100 μm diameter in a patterned manner. Measurements of ion saturation current near the PE indicate that the plasma is uniform over an area of ∼ 7 cm2, which is further confirmed by uniformity in extracted beam current through the apertures. The ion beams are applied to investigate change in electrical sheet resistance Rs of metallic thin films in a controlled manner by varying the ionic species and beam energy. Results indicate a remarkable increase in Rs with beam energy (∼ 50 % at 1 keV for Ar ions, and with ionic species (∼ 90% for Krypton ions at 0.6 keV, when 80 nm thick copper films are irradiated by ∼2 cm diameter ion beams. Ion induced surface roughness is considered as the main mechanism for this change as confirmed by atomic force microscopy (AFM measurements. Predictions for micro-beamlet induced change in Rs are discussed. The experimental results are verified using TRIM and AXCEL-INP simulations.

  17. A vertical-energy-thresholding procedure for data reduction with multiple complex curves.

    Jung, Uk; Jeong, Myong K; Lu, Jye-Chyi

    2006-10-01

    Due to the development of sensing and computer technology, measurements of many process variables are available in current manufacturing processes. It is very challenging, however, to process a large amount of information in a limited time in order to make decisions about the health of the processes and products. This paper develops a "preprocessing" procedure for multiple sets of complicated functional data in order to reduce the data size for supporting timely decision analyses. The data type studied has been used for fault detection, root-cause analysis, and quality improvement in such engineering applications as automobile and semiconductor manufacturing and nanomachining processes. The proposed vertical-energy-thresholding (VET) procedure balances the reconstruction error against data-reduction efficiency so that it is effective in capturing key patterns in the multiple data signals. The selected wavelet coefficients are treated as the "reduced-size" data in subsequent analyses for decision making. This enhances the ability of the existing statistical and machine-learning procedures to handle high-dimensional functional data. A few real-life examples demonstrate the effectiveness of our proposed procedure compared to several ad hoc techniques extended from single-curve-based data modeling and denoising procedures.

  18. Free energy landscape and multiple folding pathways of an H-type RNA pseudoknot.

    Yunqiang Bian

    Full Text Available How RNA sequences fold to specific tertiary structures is one of the key problems for understanding their dynamics and functions. Here, we study the folding process of an H-type RNA pseudoknot by performing a large-scale all-atom MD simulation and bias-exchange metadynamics. The folding free energy landscapes are obtained and several folding intermediates are identified. It is suggested that the folding occurs via multiple mechanisms, including a step-wise mechanism starting either from the first helix or the second, and a cooperative mechanism with both helices forming simultaneously. Despite of the multiple mechanism nature, the ensemble folding kinetics estimated from a Markov state model is single-exponential. It is also found that the correlation between folding and binding of metal ions is significant, and the bound ions mediate long-range interactions in the intermediate structures. Non-native interactions are found to be dominant in the unfolded state and also present in some intermediates, possibly hinder the folding process of the RNA.

  19. Terahertz carrier dynamics in graphene and graphene nanostructures

    Jensen, Søren A.; Turchinovich, Dmitry; Tielrooij, Klaas Jan

    2014-01-01

    Photoexcited charge carriers in 2D graphene and in 1D graphene nanostructures were studied with optical pump-THz probe spectroscopy. We find efficient hot-carrier multiplication in 2D graphene, and predominantly free carrier early time response in 1D nanostructures. © 2014 OSA....

  20. Multiple scattering of low energy rare gas ions: a comparison of experiment and computer simulation

    Heiland, W.; Taglauer, E.; Robinson, M.T.

    1976-01-01

    Some aspects of ion scattering below a few keV have been interpreted by multiple scattering. This can partly be simulated by chain or string models, where the single crystal surface is replaced by a chain of atoms. The computer program MARLOWE allows a simulation of solid-ion interaction, which is much closer to reality, e.g. the crystal is three-dimensional, includes lattice vibrations, electronic stopping power, different scattering potentials, etc. It is shown that the energy of the reflected ions as a function of the primary energy, lattice constant, impact angle and scattering angle can be understood within the string model. These results of the string model are confirmed by the MARLOWE calculations. For an interpretation of the measured intensities the simple string model is insufficient, whereas with MARLOWE reasonable agreement with experimental data may be achieved, if the thermal vibrations of the lattice atoms are taken into account. The experimental data include Ne + →Ni, Ne + →Ag and preliminary data on Ne + →W. The screening parameters of the scattering potentials are estimated for these ion-atom combinations. The results allow some conclusions about surface Debye temperatures. (Auth.)

  1. Zero-Point Energy Constraint for Unimolecular Dissociation Reactions. Giving Trajectories Multiple Chances To Dissociate Correctly.

    Paul, Amit K; Hase, William L

    2016-01-28

    A zero-point energy (ZPE) constraint model is proposed for classical trajectory simulations of unimolecular decomposition and applied to CH4* → H + CH3 decomposition. With this model trajectories are not allowed to dissociate unless they have ZPE in the CH3 product. If not, they are returned to the CH4* region of phase space and, if necessary, given additional opportunities to dissociate with ZPE. The lifetime for dissociation of an individual trajectory is the time it takes to dissociate with ZPE in CH3, including multiple possible returns to CH4*. With this ZPE constraint the dissociation of CH4* is exponential in time as expected for intrinsic RRKM dynamics and the resulting rate constant is in good agreement with the harmonic quantum value of RRKM theory. In contrast, a model that discards trajectories without ZPE in the reaction products gives a CH4* → H + CH3 rate constant that agrees with the classical and not quantum RRKM value. The rate constant for the purely classical simulation indicates that anharmonicity may be important and the rate constant from the ZPE constrained classical trajectory simulation may not represent the complete anharmonicity of the RRKM quantum dynamics. The ZPE constraint model proposed here is compared with previous models for restricting ZPE flow in intramolecular dynamics, and connecting product and reactant/product quantum energy levels in chemical dynamics simulations.

  2. The multiplicative effect of combining alcohol with energy drinks on adolescent gambling.

    Vieno, Alessio; Canale, Natale; Potente, Roberta; Scalese, Marco; Griffiths, Mark D; Molinaro, Sabrina

    2018-07-01

    There has been increased concern about the negative effects of adolescents consuming a combination of alcohol mixed with energy drinks (AmED). To date, few studies have focused on AmED use and gambling. The present study analyzed the multiplicative effect of AmED consumption, compared to alcohol alone, on the likelihood of at-risk or problem gambling during adolescence. Data from the ESPAD®Italia 2015 study, a cross-sectional survey conducted in a nationally representative sample of students (ages 15 to 19years) were used to examine the association between self-reported AmED use (≥6 times,≥10 times, and ≥20 times during the last month) and self-reported gambling severity. Multivariate models were used to calculate adjusted prevalence ratios to evaluate the association between alcohol use, AmED use, and gambling among a representative sample of adolescents who reported gambling in the last year and completed a gambling severity scale (n=4495). Among the 19% students classed as at-risk and problem gamblers, 43.9% were classed as AmED consumers, while 23.6% were classed as alcohol consumers (i.e. did not mix alcohol with energy drinks). In multivariate analyses that controlled for covariates, AmED consumers were three times more likely to be at-risk and problem gamblers (OR=3.05) compared to non-consuming adolescents, while the effect became less pronounced with considering those who consumed alcohol without the addition of energy drinks (OR=1.37). The present study clearly established that consuming AmED might pose a significantly greater risk of experiencing gambling-related problems among adolescents. Copyright © 2018 Elsevier Ltd. All rights reserved.

  3. Low temperature carrier redistribution dynamics in InGaN/GaN quantum wells

    Badcock, T. J., E-mail: Thomas.badcock@crl.toshiba.co.uk; Dawson, P.; Davies, M. J. [School of Physics and Astronomy, Photon Science Institute, Alan Turing Building, University of Manchester, Manchester M13 9PL (United Kingdom); Kappers, M. J.; Massabuau, F. C.-P.; Oehler, F.; Oliver, R. A.; Humphreys, C. J. [Department of Materials Science and Metallurgy, 27 Charles Babbage Road, University of Cambridge, Cambridge CB3 0FS (United Kingdom)

    2014-03-21

    We have studied the carrier recombination dynamics in an InGaN/GaN multiple quantum well structure as a function of emission energy and excitation density between temperatures of 10 K and 100 K. Under relatively low levels of excitation, the photoluminescence (PL) intensity and decay time of emission on the high energy side of the luminescence spectrum decrease strongly between 10 K and 50 K. In contrast, for emission detected on the low energy side of the spectrum, the PL intensity and decay time increase over the same temperature range. These results are consistent with a thermally activated carrier redistribution process in which the (temperature dependent) average timescale for carrier transfer into or out of a localised state depends on the energy of the given state. Thus, the transfer time out of shallow, weakly localised states is considerably shorter than the arrival time into more deeply localised states. This picture is consistent with carriers hopping between localisation sites in an uncorrelated disorder potential where the density of localised states decreases with increasing localisation depth, e.g., a exponential or Gaussian distribution resulting from random alloy disorder. Under significantly higher levels of excitation, the increased occupation fraction of the localised states results in a greater average separation distance between unoccupied localised states, causing a suppression of the spectral and dynamic signatures of the hopping transfer of carriers.

  4. Centrality and energy dependence of charged-particle multiplicities in heavy ion collisions in the context of elementary reactions

    Back, B. B.; Baker, M. D.; Barton, D. S.; Betts, R. R.; Ballintijn, M.; Bickley, A. A.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Decowski, M. P.; García, E.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Heintzelman, G. A.; Henderson, C.; Hofman, D. J.; Hollis, R. S.; Hołyński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J. L.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Lin, W. T.; Manly, S.; McLeod, D.; Michałowski, J.; Mignerey, A. C.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Skulski, W.; Steadman, S. G.; Steinberg, P.; Stephans, G. S. F.; Stodulski, M.; Sukhanov, A.; Tang, J.-L.; Teng, R.; Trzupek, A.; Vale, C.; Nieuwenhuizen, G. J. Van; Verdier, R.; Veres, G. I.; Wadsworth, B.; Wolfs, F. L. H.; Wosiek, B.; Woźniak, K.; Wuosmaa, A. H.; Wysłouch, B.

    2006-08-01

    The PHOBOS experiment at the BNL Relativistic Heavy Ion Collider has measured the total multiplicity of primary charged particles as a function of collision centrality in Au+Au collisions at sNN= 19.6, 130, and 200 GeV. An approximate independence of / on the number of participating nucleons is observed, reminiscent of “wounded nucleon” scaling (Nch∝Npart) observed in proton-nucleus collisions. Unlike p+A, the constant of proportionality does not seem to be set by the pp/p¯p data at the same energy. Rather, there seems to be a surprising correspondence with the total multiplicity measured in e+e- annihilations, as well as the rapidity shape measured over a large range. The energy dependence of the integrated multiplicity per participant pair shows that e+e- and A+A data agree over a large range of center-of-mass energies (s>20 GeV), and pp/p¯p data can be brought to agree approximately with the e+e- data by correcting for the typical energy taken away by leading particles. This is suggestive of a mechanism for soft particle production that depends mainly on the amount of available energy. It is conjectured that the dominant distinction between A+A and p+p collisions is the multiple collisions per participant, which appears to be sufficient to substantially reduce the energy taken away by leading particles.

  5. Protein carriers of conjugate vaccines

    Pichichero, Michael E

    2013-01-01

    The immunogenicity of polysaccharides as human vaccines was enhanced by coupling to protein carriers. Conjugation transformed the T cell-independent polysaccharide vaccines of the past to T cell-dependent antigenic vaccines that were much more immunogenic and launched a renaissance in vaccinology. This review discusses the conjugate vaccines for prevention of infections caused by Hemophilus influenzae type b, Streptococcus pneumoniae, and Neisseria meningitidis. Specifically, the characteristics of the proteins used in the construction of the vaccines including CRM, tetanus toxoid, diphtheria toxoid, Neisseria meningitidis outer membrane complex, and Hemophilus influenzae protein D are discussed. The studies that established differences among and key features of conjugate vaccines including immunologic memory induction, reduction of nasopharyngeal colonization and herd immunity, and antibody avidity and avidity maturation are presented. Studies of dose, schedule, response to boosters, of single protein carriers with single and multiple polysaccharides, of multiple protein carriers with multiple polysaccharides and conjugate vaccines administered concurrently with other vaccines are discussed along with undesirable consequences of conjugate vaccines. The clear benefits of conjugate vaccines in improving the protective responses of the immature immune systems of young infants and the senescent immune systems of the elderly have been made clear and opened the way to development of additional vaccines using this technology for future vaccine products. PMID:23955057

  6. Experimental characterization of a prototype secondary spectrometer for vertically scattering multiple energy analysis at cold-neutron triple axis spectrometers

    Toft-Petersen, Rasmus; Groitl, Felix; Kure, Mathias

    2016-01-01

    A thorough experimental characterization of a multiplexing backend with multiple energy analysis on a cold-neutron triple axis spectrometer (cTAS) is presented. The prototype employs two angular segments (2 theta-segments) each containing five vertically scattering analyzers (energy channels...... to the energy resolution of a standard cTAS. The dispersion relation of the antiferromagnetic excitations in MnF2 has been mapped out by performing constant energy transfer maps. These results show that the tested setup is virtually spurion free. In addition, focusing effects due to (mis...

  7. X-ray fluorescence holography and multiple-energy x-ray holography: A critical comparison of atomic images

    Len, P.M.; Gog, T.; Fadley, C.S.; Materlik, G.

    1997-01-01

    We compare x-ray fluorescence holography (XFH) and multiple-energy x-ray holography (MEXH), two techniques that have recently been used to obtain experimental three-dimensional atomic images. For single-energy holograms, these methods are equivalent by virtue of the optical reciprocity theorem. However, XFH can only record holographic information at the characteristic fluorescence energies of the emitting species, while MEXH can record holographic information at any energy above the fluorescent edge of the emitter, thus enabling the suppression of real-twin overlaps and other aberrations and artifacts in atomic images. copyright 1997 The American Physical Society

  8. Auto Carrier Transporter Loading and Unloading Improvement

    Miller, Brian

    2003-01-01

    .... Any reduction in time and energy will result in a significant savings of money. The intent of this research is to develop an algorithm to solve the Auto Carrier Transport Pickup and Delivery Problem...

  9. Multiplicities of pions and slow protons in nuclear interactions at relativistic energies

    Idh, J.

    1993-02-01

    The distributions of the transverse energy and the multiplicity of charged particles in oxygen induced reactions are examined in the Fritiof Monte Carlo model. The shape of the distributions are found to be determined by the distribution of the number of particle-emitting sources, i.e. strings. The fluctuations in particle emission from each string is hidden by these much larger fluctuations. The fluctuations of these distributions when partial phase space coverage is used is well described by purely stochastic emission. Distributions of slow singly-charged fragments in the target region is measured for both hadron and oxygen induced reactions. The distributions extends to much larger values than simulated data from the Monte Carlo models Fritiof 1.7 and Venus 3.14. The hadron induced reactions give distributions that can be reproduced assuming that each participating target nucleon produced fragments according to a geometric distribution, where the average number of fragments per participating target nucleon is target dependent. The extracted average number of produced fragments are similar for proton and pion induced reactions. When the tails of the distributions are studied their extension can be parametrized, and for such an approach a target dependence of A 2/3 is found for all projectiles. The data for 60 and 200 A GeV are almost identical for distributions as well as angular and energy examined distributions. The angular distributions follow an exponential in cos(θ). If the slopes of the angular distributions are examined and target dependences as well as centrality dependences are extracted. For light targets there is a strong target dependence, but for targets heavier than copper there is not any great differences. The centrality dependence is almost negligible for a gold-target but for a copper-target the most central collisions have more forward peaked distributions. (62 refs.)

  10. Multiple and double scattering contributions to depth resolution and low energy background in hydrogen elastic recoil detection

    Wielunski, L S [Commonwealth Scientific and Industrial Research Organisation (CSIRO), Lindfield, NSW (Australia). Div. of Applied Physics

    1997-12-31

    The sensitivity of hydrogen elastic recoil detection ( ERD ) is usually limited by the low energy background in the ERD spectrum. A number of 4.5 MeV He{sup ++} hydrogen ERD spectra from different hydrogen implanted samples are compared. The samples are chosen with different atomic numbers from low Z (carbon) to high Z (tungsten carbide) to observe the effects of multiple scattering and double scattering within the sample material. The experimental depth resolution and levels of the low energy background in ERD spectra are compared with theoretical predictions from multiple and double scattering. 10 refs., 2 tabs., 5 figs.

  11. Multiple and double scattering contributions to depth resolution and low energy background in hydrogen elastic recoil detection

    Wielunski, L.S. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), Lindfield, NSW (Australia). Div. of Applied Physics

    1996-12-31

    The sensitivity of hydrogen elastic recoil detection ( ERD ) is usually limited by the low energy background in the ERD spectrum. A number of 4.5 MeV He{sup ++} hydrogen ERD spectra from different hydrogen implanted samples are compared. The samples are chosen with different atomic numbers from low Z (carbon) to high Z (tungsten carbide) to observe the effects of multiple scattering and double scattering within the sample material. The experimental depth resolution and levels of the low energy background in ERD spectra are compared with theoretical predictions from multiple and double scattering. 10 refs., 2 tabs., 5 figs.

  12. Transverse energy and charged particle multiplicity in 14.6 GeV/c proton-nucleus collisions

    Wang, Gang

    1995-01-01

    Transverse energy and charged particle multiplicity produced in 14.6 GeV/c p + Al and p + Pb collisions have been studied using the E814 set-up at the BNL-AGS. Measurements of dσ/dE T , dE T /dη,dσ/dN c , and dN c /dη are presented. From the present data the mean transverse energy per particle is obtained and it is compared to values observed in Si induced collisions at the same energy In contrast to what is observed in nucleus-nucleus collisions, a very weak correlation is found between the transverse energy and the charged particle multiplicity. These results are compared to the predictions of various theoretical models used to describe heavy-ion collisions. The event generators RQMD and HIJET reproduce well the pseudorapidity distribution of both the transverse energy and charged particle multiplicity, whereas FRITIOF fails to reproduce the measured distributions. Contrary to what had been suggested previously in a Si + A study, the present study shows that the pseudorapidity dependence of charged particle multiplicity distributions do not follow KNO scaling. (author)

  13. Multiple binding modes of ibuprofen in human serum albumin identified by absolute binding free energy calculations

    Evoli, Stefania

    2016-11-10

    Human serum albumin possesses multiple binding sites and transports a wide range of ligands that include the anti-inflammatory drug ibuprofen. A complete map of the binding sites of ibuprofen in albumin is difficult to obtain in traditional experiments, because of the structural adaptability of this protein in accommodating small ligands. In this work, we provide a set of predictions covering the geometry, affinity of binding and protonation state for the pharmaceutically most active form (S-isomer) of ibuprofen to albumin, by using absolute binding free energy calculations in combination with classical molecular dynamics (MD) simulations and molecular docking. The most favorable binding modes correctly reproduce several experimentally identified binding locations, which include the two Sudlow\\'s drug sites (DS2 and DS1) and the fatty acid binding sites 6 and 2 (FA6 and FA2). Previously unknown details of the binding conformations were revealed for some of them, and formerly undetected binding modes were found in other protein sites. The calculated binding affinities exhibit trends which seem to agree with the available experimental data, and drastically degrade when the ligand is modeled in a protonated (neutral) state, indicating that ibuprofen associates with albumin preferentially in its charged form. These findings provide a detailed description of the binding of ibuprofen, help to explain a wide range of results reported in the literature in the last decades, and demonstrate the possibility of using simulation methods to predict ligand binding to albumin.

  14. Transverse energy and multiplicity distributions of p-p and A+A interactions

    Tannenbaum, M.J.

    1990-01-01

    Data from AGS-E802 have been presented at the percent HIPAGS workshop at BNL, published in journals and in conference proceedings (St. Malo, Moriond), to which the reader is referred. Two results are mentioned here. The Lead Glass distribution dE T 0 /dn from central O + Au collisions can be compared to the spectrometer dn (π-)/dy from central Si + Au collisions. The agreement of the two distributions is excellent and confirms that the estimated position and value of the maximum in the distribution η|max, dE T /dη|max, and the width Δη FWHM , from the PbGl data are reasonable, and that nothing exceptional is occurring outside of the PbGl acceptance. Additionally, these data, and previous measurements of pseudorapidity distributions of multiplicity and Transverse Energy at both the AGS and CERN are analyzed in an acceptance-independent and model-independent method, with the conclusion that simple considerations of nuclear geometry do not provide an explanation of the different √ s NN dependences observed in 16 O + Au and p-p reactions. 13 refs., 2 figs

  15. Effectiveness of energy conservation management on fatigue and participation in multiple sclerosis: A randomized controlled trial.

    Blikman, Lyan Jm; van Meeteren, Jetty; Twisk, Jos Wr; de Laat, Fred Aj; de Groot, Vincent; Beckerman, Heleen; Stam, Henk J; Bussmann, Johannes Bj

    2017-10-01

    Fatigue is a frequently reported and disabling symptom in multiple sclerosis (MS). To investigate the effectiveness of an individual energy conservation management (ECM) intervention on fatigue and participation in persons with primary MS-related fatigue. A total of 86 severely fatigued and ambulatory adults with a definite diagnosis of MS were randomized in a single-blind, two-parallel-arm randomized clinical trial to the ECM group or the information-only control group in outpatient rehabilitation departments. Blinded assessments were carried out at baseline and at 8, 16, 26 and 52 weeks after randomization. Primary outcomes were fatigue (fatigue subscale of Checklist Individual Strength - CIS20r) and participation (Impact on Participation and Autonomy scale - IPA). Modified intention-to-treat analysis was based on 76 randomized patients (ECM, n = 36; MS nurse, n=40). No significant ECM effects were found for fatigue (overall difference CIS20r between the groups = -0.81; 95% confidence interval (CI), -3.71 to 2.11) or for four out of five IPA domains. An overall unfavourable effect was found in the ECM group for the IPA domain social relations (difference between the groups = 0.19; 95% CI, 0.03 to 0.35). The individual ECM format used in this study did not reduce MS-related fatigue and restrictions in participation more than an information-only control condition.

  16. Multiple collision effects on the antiproton production by high energy proton (100 GeV - 1000 GeV)

    Takahashi, Hiroshi; Powell, J.

    1987-01-01

    Antiproton production rates which take into account multiple collision are calculated using a simple model. Methods to reduce capture of the produced antiprotons by the target are discussed, including geometry of target and the use of a high intensity laser. Antiproton production increases substantially above 150 GeV proton incident energy. The yield increases almost linearly with incident energy, alleviating space charge problems in the high current accelerator that produces large amounts of antiprotons

  17. Charged particle multiplicity in Au-Au and d-Au collisions at RHIC energies

    Arsene, Ionut

    2003-01-01

    RHIC (Relativistic Heavy Ion Collider) is the baggiest heavy ion accelerator in the world at this moment and in the experiments performed there is the chance to observe the first signals of the so called 'Quark Gluon Plasma', a veritable cornerstone for Relativistic Heavy Ion Physics. At its present energy, √(s NN ) = 200 GeV, in the four experiments taking place currently at RHIC (PHENIX, STAR, BRAHMS and PHOBOS) some results on this subject are expected. One of the signals for the formation of QGP is, for example, a saturation of the number of parton collisions in central nucleus-nucleus collisions that could lead to a limit on the production of charged particles. The present work investigates the multiplicity distributions of charged particles emitted in relativistic heavy ion collisions between gold nuclei at √(s NN ) = 130 GeV and √(s NN ) = 200 GeV and between deuteron and gold at √(s NN ) 200 GeV. With these distributions we can obtain immediately the charged particle distribution normalized to the number of participating pairs, a more relevant information about the phenomena investigated. The data is obtained using several detectors of the BRAHMS experiment, namely: the Multiplicity Array (MA), the Beam-Beam Counters (BBC), and the Zero Degree Calorimeters (ZDC). The MA cover the mid-rapidity region eta < |2.5| with a Si-strip detector array (SMA) close to the beam pipe (5.3 cm) and a plastic-scintillator tile array (TMA) placed around the Si-strip detector at about 13 cm from the beam axis. The BBC contain two sets of Cherenkov detectors placed at ± 220 cm from the nominal interaction point on both sides. These detectors cover the high rapidity part of the distribution. Due to the very good timing resolution, these detectors are used also for vertex determination and triggering for the entire experiment. The ZDC detectors measure the spectator fragments which are not scattered from collision. These detectors are used also for timing purposes. In

  18. Designing for Multiple Stakeholder Interests within the Humanitarian Market: The Case of Off-Grid Energy Devices

    Nielsen, Brita Fladvad; Rodrigues Santos, Ana Laura

    2013-01-01

    A "humanitarian market" for off-grid renewable energy technologies for displaced populations in remote areas has emerged. Within this market, there are multiple stakeholder agendas. End-user needs and sustainable development goals are currently not considered through the customer-enterprise relationship and the applied product and…

  19. Estimating the two-particle $K$-matrix for multiple partial waves and decay channels from finite-volume energies

    Morningstar, Colin; Bulava, John; Singha, Bijit

    2017-01-01

    An implementation of estimating the two-to-two $K$-matrix from finite-volume energies based on the L\\"uscher formalism and involving a Hermitian matrix known as the "box matrix" is described. The method includes higher partial waves and multiple decay channels. Two fitting procedures for estimating...

  20. Carrier dynamics in graphene. Ultrafast many-particle phenomena

    Malic, E.; Brem, S.; Jago, R. [Department of Physics, Chalmers University of Technology, Goeteborg (Sweden); Winzer, T.; Wendler, F.; Knorr, A. [Institut fuer Theoretische Physik, Technische Universitaet Berlin (Germany); Mittendorff, M.; Koenig-Otto, J.C.; Schneider, H.; Helm, M.; Winnerl, S. [Helmholtz-Zentrum Dresden-Rossendorf, Dresden (Germany); Ploetzing, T.; Neumaier, D. [Advanced Microelectronic Center Aachen, AMO GmbH, Aachen (Germany)

    2017-11-15

    Graphene is an ideal material to study fundamental Coulomb- and phonon-induced carrier scattering processes. Its remarkable gapless and linear band structure opens up new carrier relaxation channels. In particular, Auger scattering bridging the valence and the conduction band changes the number of charge carriers and gives rise to a significant carrier multiplication - an ultrafast many-particle phenomenon that is promising for the design of highly efficient photodetectors. Furthermore, the vanishing density of states at the Dirac point combined with ultrafast phonon-induced intraband scattering results in an accumulation of carriers and a population inversion suggesting the design of graphene-based terahertz lasers. Here, we review our work on the ultrafast carrier dynamics in graphene and Landau-quantized graphene is presented providing a microscopic view on the appearance of carrier multiplication and population inversion. (copyright 2017 by WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Analysis of the residential location choice and household energy consumption behavior by incorporating multiple self-selection effects

    Yu Biying; Junyi Zhang; Fujiwara, Akimasa

    2012-01-01

    It is expected that the residential location choice and household energy consumption behavior might correlate with each other. Besides, due to the existence of self-selection effects, the observed inter-relationship between them might be the spurious result of the fact that some unobserved variables are causing both. These concerns motivate us to (1) consider residential location choice and household energy consumption behavior (for both in-home appliances and out-of-home cars) simultaneously and, (2) explicitly control self-selection effects so as to capture a relatively true effect of land-use policy on household energy consumption behavior. An integrated model termed as joint mixed Multinomial Logit-Multiple Discrete-Continuous Extreme Value model is presented here to identify the sensitivity of household energy consumption to land use policy by considering multiple self-selection effects. The model results indicate that land-use policy do play a great role in changing Beijing residents’ energy consumption pattern, while the self-selection effects cannot be ignored when evaluating the effect of land-use policy. Based on the policy scenario design, it is found that increasing recreational facilities and bus lines in the neighborhood can greatly promote household's energy-saving behavior. Additionally, the importance of “soft policy” and package policy is also emphasized in the context of Beijing. - Highlights: ► Representing residential choice and household energy consumption behavior jointly. ► Land use policy is found effective to control the household energy use in Beijing. ► Multiple self-selection effects are posed to get the true effect of land use policy. ► Significant self-selection effects call an attention to the soft policy in Beijing. ► The necessity of package policy on saving Beijing residents’ energy use is confirmed.

  2. Focusing of light energy inside a scattering medium by controlling the time-gated multiple light scattering

    Jeong, Seungwon; Lee, Ye-Ryoung; Choi, Wonjun; Kang, Sungsam; Hong, Jin Hee; Park, Jin-Sung; Lim, Yong-Sik; Park, Hong-Gyu; Choi, Wonshik

    2018-05-01

    The efficient delivery of light energy is a prerequisite for the non-invasive imaging and stimulating of target objects embedded deep within a scattering medium. However, the injected waves experience random diffusion by multiple light scattering, and only a small fraction reaches the target object. Here, we present a method to counteract wave diffusion and to focus multiple-scattered waves at the deeply embedded target. To realize this, we experimentally inject light into the reflection eigenchannels of a specific flight time to preferably enhance the intensity of those multiple-scattered waves that have interacted with the target object. For targets that are too deep to be visible by optical imaging, we demonstrate a more than tenfold enhancement in light energy delivery in comparison with ordinary wave diffusion cases. This work will lay a foundation to enhance the working depth of imaging, sensing and light stimulation.

  3. The impact of energy conservation in transport models on the π−/π+ multiplicity ratio in heavy-ion collisions and the symmetry energy

    M.D. Cozma

    2016-02-01

    Full Text Available The charged pion multiplicity ratio in intermediate energy central heavy-ion collisions has been proposed as a suitable observable to constrain the high density dependence of the isovector part of the equation of state. A comparison of various transport model predictions with existing experimental data has led, however, to contradictory results. Using an upgraded version of the Tübingen QMD transport model, which allows the conservation of energy at a local or global level by accounting for the potential energy of hadrons in two-body collisions and leading thus to particle production threshold shifts, we demonstrate that compatible constraints for the symmetry energy stiffness can be extracted from pion multiplicity and elliptic flow observables. However, pion multiplicities and ratios are proven to be highly sensitive to the yet unknown isovector part of the in-medium Δ(1232 potential which hinders, at present, the extraction of meaningful information on the high density dependence of the symmetry energy. A solution to this problem together with the inclusion of contributions presently neglected, such as in-medium pion potentials and retardation effects, are needed for a final verdict on this topic.

  4. Ultrafast dynamics in ZnO/ZnMgO multiple quantum wells

    Wen, X M; Davis, J A; McDonald, D; Dao, L V; Hannaford, P; Coleman, V A; Tan, H H; Jagadish, C; Koike, K; Sasa, S; Inoue, M; Yano, M

    2007-01-01

    We have investigated carrier relaxation and exciton recombination dynamics in ZnO/ZnMgO multiple quantum wells using femtosecond pump-probe techniques at room temperature. For a probe energy above the band gap, the hot carriers exhibit an effective relaxation by longitudinal optical phonon scattering with a cooling time of 700-850 fs. By detecting the emission near the band-gap, a longer decay time of a few picoseconds was observed which is attributed to acoustic phonon scattering. As the probe energy is decreased further, the decay time continues to increase due to the transitions of exciton recombination or localized carrier recombination

  5. Charge-carrier mobilities in disordered semiconducting polymers: effects of carrier density and electric field [refereed

    Meisel, K.D.; Pasveer, W.F.; Cottaar, J.; Tanase, C.; Coehoorn, R.; Bobbert, P.A.; Blom, P.W.M.; Leeuw, de D.M.; Michels, M.A.J.

    2006-01-01

    We model charge transport in disordered semiconducting polymers by hopping of charge carriers on a square lattice of sites with Gaussian on-site energy disorder, using Fermi-Dirac statistics. From numerically exact solns. of the Master equation, we study the dependence of the charge-carrier mobility

  6. Charge-carrier mobilities in disordered semiconducting polymers : effects of carrier density and electric field

    Meisel, K.D.; Pasveer, W.F.; Cottaar, J.; Tanase, C.; Coehoorn, R.; Bobbert, P.A.; Blom, P.W.M.; Leeuw, D.M. de; Michels, M.A.J.

    2006-01-01

    We model charge transport in disordered semiconducting polymers by hopping of charge carriers on a square lattice of sites with Gaussian on-site energy disorder, using Fermi-Dirac statistics. From numerically exact solutions of the Master equation, we study the dependence of the charge-carrier

  7. Simulation of a resonant-type ring magnet power supply with multiple resonant cells and energy storage chokes

    Kim, J.M.S.; Blackmore, E.W.; Reiniger, K.W.

    1992-01-01

    For the TRIUMF KAON Factory Booster Ring, a resonant-type magnet power supply has been proposed for the dipole magnet excitation. The Booster Ring magnet power supply system based on resonant circuits, coupled with distributed energy make-up networks, is a complex system, sensitive to many system parameters. When multiple resonant cells, each with its own energy make-up network, are connected in a ring, it is very difficult to derive closed-form solutions to determine the operating conditions of the power supply system. A meaningful way to understand and analyze such a complex system is to use a simulation tool. This paper presents the analysis of operating conditions of the resonant-type ring magnet power supply with multiple resonant cells, using the circuit simulation tool, SPICE. The focus of the study is on the effect of circuit parameter variations in energy storage chokes

  8. How to deal with multiple binding poses in alchemical relative protein-ligand binding free energy calculations.

    Kaus, Joseph W; Harder, Edward; Lin, Teng; Abel, Robert; McCammon, J Andrew; Wang, Lingle

    2015-06-09

    Recent advances in improved force fields and sampling methods have made it possible for the accurate calculation of protein–ligand binding free energies. Alchemical free energy perturbation (FEP) using an explicit solvent model is one of the most rigorous methods to calculate relative binding free energies. However, for cases where there are high energy barriers separating the relevant conformations that are important for ligand binding, the calculated free energy may depend on the initial conformation used in the simulation due to the lack of complete sampling of all the important regions in phase space. This is particularly true for ligands with multiple possible binding modes separated by high energy barriers, making it difficult to sample all relevant binding modes even with modern enhanced sampling methods. In this paper, we apply a previously developed method that provides a corrected binding free energy for ligands with multiple binding modes by combining the free energy results from multiple alchemical FEP calculations starting from all enumerated poses, and the results are compared with Glide docking and MM-GBSA calculations. From these calculations, the dominant ligand binding mode can also be predicted. We apply this method to a series of ligands that bind to c-Jun N-terminal kinase-1 (JNK1) and obtain improved free energy results. The dominant ligand binding modes predicted by this method agree with the available crystallography, while both Glide docking and MM-GBSA calculations incorrectly predict the binding modes for some ligands. The method also helps separate the force field error from the ligand sampling error, such that deviations in the predicted binding free energy from the experimental values likely indicate possible inaccuracies in the force field. An error in the force field for a subset of the ligands studied was identified using this method, and improved free energy results were obtained by correcting the partial charges assigned to the

  9. How To Deal with Multiple Binding Poses in Alchemical Relative Protein–Ligand Binding Free Energy Calculations

    2016-01-01

    Recent advances in improved force fields and sampling methods have made it possible for the accurate calculation of protein–ligand binding free energies. Alchemical free energy perturbation (FEP) using an explicit solvent model is one of the most rigorous methods to calculate relative binding free energies. However, for cases where there are high energy barriers separating the relevant conformations that are important for ligand binding, the calculated free energy may depend on the initial conformation used in the simulation due to the lack of complete sampling of all the important regions in phase space. This is particularly true for ligands with multiple possible binding modes separated by high energy barriers, making it difficult to sample all relevant binding modes even with modern enhanced sampling methods. In this paper, we apply a previously developed method that provides a corrected binding free energy for ligands with multiple binding modes by combining the free energy results from multiple alchemical FEP calculations starting from all enumerated poses, and the results are compared with Glide docking and MM-GBSA calculations. From these calculations, the dominant ligand binding mode can also be predicted. We apply this method to a series of ligands that bind to c-Jun N-terminal kinase-1 (JNK1) and obtain improved free energy results. The dominant ligand binding modes predicted by this method agree with the available crystallography, while both Glide docking and MM-GBSA calculations incorrectly predict the binding modes for some ligands. The method also helps separate the force field error from the ligand sampling error, such that deviations in the predicted binding free energy from the experimental values likely indicate possible inaccuracies in the force field. An error in the force field for a subset of the ligands studied was identified using this method, and improved free energy results were obtained by correcting the partial charges assigned to the

  10. Using Flow Electrodes in Multiple Reactors in Series for Continuous Energy Generation from Capacitive Mixing

    Hatzell, Marta C.; Hatzell, Kelsey B.; Logan, Bruce E.

    2014-01-01

    Efficient conversion of “mixing energy” to electricity through capacitive mixing (CapMix) has been limited by low energy recoveries, low power densities, and noncontinuous energy production resulting from intermittent charging and discharging cycles

  11. Driving factors for the regional implementation of renewable energy ‐ A multiple case study on the German energy transition

    Lutz, Lotte Marie; Fischer, Lisa-Britt; Newig, Jens; Lang, Daniel Johannes

    2017-01-01

    Understanding what drives the regional implementation of renewable energy is a prerequisite for energy transitions toward a post-fossil-based energy economy. This paper presents an empirical analysis of driving factors for the regional implementation and use of renewable energy. We tested literature-derived driving factors in a comparative analysis of 18 selected study regions using Rough Set Analysis and performance analysis. We paid special attention to common combinations of driving factors, which we understand as established practices concerning the use and implementation of renewable energy. Our findings confirm most of the driving factors identified in the literature, for example the existence of key actors, knowledge exchange, or the use of goals and milestones. We also observe differences in key driving factors between highly successful and less successful regions, especially regarding funding opportunities. The results may support policy makers who aim to successfully implement renewable energy at a regional level. - Highlights: • We analyzed driving factors for RE implementation in 18 best-practice regions. • Most driving factors from transition and governance literature were confirmed. • We identified common successful practices concerning RE implementation.

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

    Psihas Olmedo, Silvia Fernanda [Univ. of Minnesota, Duluth, MN (United States)

    2013-06-01

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

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

    Psihas Olmedo, Silvia Fernanda [Fermi National Accelerator Lab. (FNAL), Batavia, IL (United States)

    2015-01-01

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

  14. Misconceptions and Biases in German Students' Perception of Multiple Energy Sources: Implications for Science Education

    Lee, Roh Pin

    2016-01-01

    Misconceptions and biases in energy perception could influence people's support for developments integral to the success of restructuring a nation's energy system. Science education, in equipping young adults with the cognitive skills and knowledge necessary to navigate in the confusing energy environment, could play a key role in paving the way…

  15. Modelling Reliability of Supply and Infrastructural Dependency in Energy Distribution Systems

    Helseth, Arild

    2008-01-01

    This thesis presents methods and models for assessing reliability of supply and infrastructural dependency in energy distribution systems with multiple energy carriers. The three energy carriers of electric power, natural gas and district heating are considered. Models and methods for assessing reliability of supply in electric power systems are well documented, frequently applied in the industry and continuously being subject to research and improvement. On the contrary, there are compar...

  16. $\\gamma$-ray energy spectra and multiplicities from the neutron-induced fission of $^{235}$U using STEFF

    An experiment is proposed to use the STEFF spectrometer at n_TOF to study fragment $\\gamma$-correlations following the neutron-induced fission of $^{235}$U. The STEFF array of 12 NaI detectors will allow measurements of the single $\\gamma$-energy, the $\\gamma$ multiplicity, and the summed $\\gamma$energy distributions as a function of the mass and charge split, and deduced excitation energy in the fission event. These data will be used to study the origin of fission-fragment angular momenta, examining angular distribution eects as a function of incident neutron energy. The principal application of this work is in meeting the NEA high-priority request for improved $\\gamma$ray data from $^{235}$U(n; F). To improve the detection rate and expand the range of detection angles, STEFF will be modied to include two new ssion-fragment detectors each at 45 to the beam direction.

  17. Peptide-Carrier Conjugation

    Hansen, Paul Robert

    2015-01-01

    To produce antibodies against synthetic peptides it is necessary to couple them to a protein carrier. This chapter provides a nonspecialist overview of peptide-carrier conjugation. Furthermore, a protocol for coupling cysteine-containing peptides to bovine serum albumin is outlined....

  18. Air Carrier Traffic Statistics.

    2013-11-01

    This report contains airline operating statistics for large certificated air carriers based on data reported to U.S. Department of Transportation (DOT) by carriers that hold a certificate issued under Section 401 of the Federal Aviation Act of 1958 a...

  19. Air Carrier Traffic Statistics.

    2012-07-01

    This report contains airline operating statistics for large certificated air carriers based on data reported to U.S. Department of Transportation (DOT) by carriers that hold a certificate issued under Section 401 of the Federal Aviation Act of 1958 a...

  20. All orders transport theory from the multiple scattering expansion of the self-energy. The central cuts

    Gagnon, J.S.; Fillion-Gourdeau, F.; Sangyong Jeong; RIKEN Research Center, Upton, NY

    2006-01-01

    We use the full multiple scattering expansion of the retarded self-energy to obtain the gain and loss rates present in the Kadanoff-Baym relativistic transport equation. The rates we obtain include processes with any number of particles. As a first approximation, we only consider central cuts in the self-energies, but otherwise our results are general. We specialize to the case of scalar field theory to compare with lowest order results. The main application of this work is relativistic transport theory of very dense systems, such as the quark-gluon plasma or the early universe, where multi-particle interactions are important. (author)

  1. Configuration of supply chains in emerging industries: a multiple-case study in the wave-and-tidal energy industry

    Bjørgum, Øyvind; Netland, Torbjørn H.

    2017-01-01

    Companies in emerging industries face particular challenges in configuring effective supply chains. In this paper, we build on transaction cost economics to explore how supply chains can be configured in emerging industries. We focus on two key aspects of supply chain configuration: the make-or-buy decision and the strength of the ties between a focal firm and its suppliers. We utilise a multiple-case study methodology, including seven start-up companies in the emerging wave-and-tidal energy ...

  2. On the dependance of the ''normalized multiplicity'' of particles produced in proton-nucleus interactions on the primary energy

    Babecki, J.

    1975-01-01

    The mean ''normalized multiplicities'' of particles produced in p-nucleus interactions: with the leading particles (R 1 ) and without them (R 2 ) were calculated from the emulsion data. The independence of R 2 of the primary energy E 0 were stated in very wide interval of E 0 from 6.2 to thousands of GeV. R 2 is approximately equal to the mean number of collisions of the primary particle in the nucleus. (author)

  3. submitter Metabolomic Profile of Low–Copy Number Carriers at the Salivary α-Amylase Gene Suggests a Metabolic Shift Toward Lipid-Based Energy Production

    Arredouani, Abdelilah; Culeddu, Nicola; Moustafa, Julia El-Sayed; Tichet, Jean; Balkau, Beverley; Brousseau, Thierry; Manca, Marco; Falchi, Mario

    2016-01-01

    Low serum salivary amylase levels have been associated with a range of metabolic abnormalities, including obesity and insulin resistance. We recently suggested that a low copy number at the AMY1 gene, associated with lower enzyme levels, also increases susceptibility to obesity. To advance our understanding of the effect of AMY1 copy number variation on metabolism, we compared the metabolomic signatures of high– and low–copy number carriers. We analyzed, using mass spectrometry and nuclear magnetic resonance (NMR), the sera of healthy normal-weight women carrying either low–AMY1 copies (LAs: four or fewer copies; n = 50) or high–AMY1 copies (HAs: eight or more copies; n = 50). Best-fitting multivariate models (empirical P < 1 × $10^{−3})$ of mass spectrometry and NMR data were concordant in showing differences in lipid metabolism between the two groups. In particular, LA carriers showed lower levels of long- and medium-chain fatty acids, and higher levels of dicarboxylic fatty acids and 2-hydrox...

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

    Alt, C.; Baatar, B.; Barna, D.; Bartke, J.; Betev, L.; Bialkowska, Helena; Blume, Christoph; Boimska, B.; Botje, Michiel; Bracinik, J.; Bramm, R.; Buncic, P.; Cerny, V.; Christakoglou, P.; Chung, P.; Chvala, O.; Cramer, J.G.; Csato, P.; Dinkelaker, P.; Eckardt, V.; Flierl, D.; Fodor, Zoltan; Foka, P.; Friese, Volker; Gal, J.; Gazdzicki, Marek; Genchev, V.; Georgopoulos, G.; Gladysz, E.; Grebieszkow, K.; Hegyi, S.; Hohne, C.; Kadija, K.; Karev, A.; Kikola, D.; Kliemant, M.; Kniege, S.; Kolesnikov, V.I.; Kornas, E.; Korus, R.; Kowalski, M.; Kraus, I.; Kreps, M.; Laszlo, A.; Lacey, Roy A.; van Leeuwen, M.; Levai, P.; Litov, Leandar; Makariev, M.; Malakhov, A.I.; Mateev, M.; Melkumov, G.L.; Mischke, A.; Mitrovski, M.; Molnar, J.; Mrowczynski, St.; Nicolic, V.; Palla, G.; Panagiotou, Apostolos D.; Panayotov, D.; Peryt, W.; Pikna, M.; Pluta, J.; Prindle, D.; Puhlhofer, F.; Renfordt, R.; Roland, C.; Roland, Gunther; Rybczynski, M.; Rybicki, A.; Sandoval, Andres; Schmitz, Norbert; Schuster, T.; Seyboth, P.; Sikler, F.; Sitar, B.; Skrzypczak, E.; Slodkowski, M.; Stefanek, Grzegorz; Stock, R.; Strabel, C.; Strobele, H.; Susa, T.; Szentpetery, I.; Sziklai, J.; Szuba, M.; Szymanski, P.; Trubnikov, V.; Utvic, M.; Varga, D.; Vassiliou, M.; Veres, G.I.; Vesztergombi, G.; Vranic, D.; Wetzler, A.; Wlodarczyk, Z.; Wojtaszek, A.; Yoo, I.K.

    2008-01-01

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

  5. Extracting hot carriers from photoexcited semiconductor nanocrystals

    Zhu, Xiaoyang

    2014-12-10

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

  6. Optimal diversity of renewable energy alternatives under multiple criteria: An application to the UK

    Shmelev, S.E.; van den Bergh, J.C.J.M.

    2016-01-01

    We propose a multi-criteria analysis of alternative combinations of renewable energy technologies to meet a sustainable energy supply. It takes into account a range of criteria to reflect relevant environmental, social and economic considerations, capture the value of diversity, and reflect

  7. Ultrafast carrier thermalization in lead iodide perovskite probed with two-dimensional electronic spectroscopy.

    Richter, Johannes M; Branchi, Federico; Valduga de Almeida Camargo, Franco; Zhao, Baodan; Friend, Richard H; Cerullo, Giulio; Deschler, Felix

    2017-08-29

    In band-like semiconductors, charge carriers form a thermal energy distribution rapidly after optical excitation. In hybrid perovskites, the cooling of such thermal carrier distributions occurs on timescales of about 300 fs via carrier-phonon scattering. However, the initial build-up of the thermal distribution proved difficult to resolve with pump-probe techniques due to the requirement of high resolution, both in time and pump energy. Here, we use two-dimensional electronic spectroscopy with sub-10 fs resolution to directly observe the carrier interactions that lead to a thermal carrier distribution. We find that thermalization occurs dominantly via carrier-carrier scattering under the investigated fluences and report the dependence of carrier scattering rates on excess energy and carrier density. We extract characteristic carrier thermalization times from below 10 to 85 fs. These values allow for mobilities of 500 cm 2  V -1  s -1 at carrier densities lower than 2 × 10 19  cm -3 and limit the time for carrier extraction in hot carrier solar cells.Carrier-carrier scattering rates determine the fundamental limits of carrier transport and electronic coherence. Using two-dimensional electronic spectroscopy with sub-10 fs resolution, Richter and Branchi et al. extract carrier thermalization times of 10 to 85 fs in hybrid perovskites.

  8. Importance of polaron effects for charge carrier mobility above and ...

    It is shown that the scattering of polaronic charge carriers and bosonic Cooper pairs at acoustic and optical phonons are responsible for the charge carrier mobility above and below the PG temperature. We show that the energy scales of the binding energies of large polarons and polaronic Cooper pairs can be identified by ...

  9. Using synthetic data to evaluate multiple regression and principal component analyses for statistical modeling of daily building energy consumption

    Reddy, T.A. (Energy Systems Lab., Texas A and M Univ., College Station, TX (United States)); Claridge, D.E. (Energy Systems Lab., Texas A and M Univ., College Station, TX (United States))

    1994-01-01

    Multiple regression modeling of monitored building energy use data is often faulted as a reliable means of predicting energy use on the grounds that multicollinearity between the regressor variables can lead both to improper interpretation of the relative importance of the various physical regressor parameters and to a model with unstable regressor coefficients. Principal component analysis (PCA) has the potential to overcome such drawbacks. While a few case studies have already attempted to apply this technique to building energy data, the objectives of this study were to make a broader evaluation of PCA and multiple regression analysis (MRA) and to establish guidelines under which one approach is preferable to the other. Four geographic locations in the US with different climatic conditions were selected and synthetic data sequence representative of daily energy use in large institutional buildings were generated in each location using a linear model with outdoor temperature, outdoor specific humidity and solar radiation as the three regression variables. MRA and PCA approaches were then applied to these data sets and their relative performances were compared. Conditions under which PCA seems to perform better than MRA were identified and preliminary recommendations on the use of either modeling approach formulated. (orig.)

  10. Norwegian building's energy policy: multiple and inconsistent; Norsk byggenergipolitikk: mangfoldig og inkonsistent

    Boasson, Elin Lerum

    2009-09-15

    Historically, Norwegian building-construction policies have been part of the state's welfare policy. After 2000, a new conceptualisation of buildings emerged in Europe. Buildings were now regarded as a part of the energy system. The term 'energy performance of buildings' covers both the thermal quality of the building envelope and on-site energy production. In 2002 the EU developed an Energy Performance of Buildings Directive, while EU state aid regulations constrained national support schemes directed at fostering buildings with high energy performance. The building construction industry is a loosely coupled industry, and by year 2000 building construction was rather de-politicized. Although governmental regulations tend to be developed by governmental organisations and research communities in collaboration, political executives have, from time to time after year 2000, engaged directly in the development policy regarding energy performance of buildings. This report explores: 1) Why have Norwegian governments, in the period between 2000 and 2008, developed four strains of policies directed toward promoting buildings with high energy performance? 2) How did the European environment, the building construction sector (industry and governmental regulators) and the Norwegian governmental hierarchical steering intervene and shape the outcomes? (Author)

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

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

    2008-01-01

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

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

    Herron, Kerry Gale (University of Oklahoma, Norman, OK); Jenkins-Smith, Hank C. (University of Oklahoma, Norman, OK)

    2008-01-01

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

  13. Multiple scattering in electron fluid and energy loss in multi-ionic targets

    Deutsch, C., E-mail: claude.deutsch@u-psud.fr [LPGP, UParis-Sud, 91405-Orsay (France); Tahir, N.A. [GSI, 1Planck Str., 64291-Darmstadt (Germany); Barriga-Carrasco, M. [ETSII, UCastilla-la-Mancha, 13071 Ciudad-Real (Spain); Ceban, V. [LPGP, UParis-Sud, 91405-Orsay (France); Fromy, P. [CRI, UParis-Sud, 91405-Orsay (France); Gilles, D. [CEA/Saclay/DSM/IRFU/SAP, 91191-Gif-s-Yvette (France); Leger, D. [Laboratoire Monthouy, UValenciennes-Hainaut Cambresis (France); Maynard, G. [LPGP, UParis-Sud, 91405-Orsay (France); Tashev, B. [Department of Physics, KazNu, Tole Bi82, Almaty (Kazakhstan); Volpe, L. [Department of Physics, UMilano-Bicocca, Milano 20126 (Italy)

    2014-01-01

    Extensions of the standard stopping model (SSM) for ion projectiles interacting with dense targets of timely concern for ICF and WDM are reviewed. They include multiple scattering on partially degenerate electrons, low velocity ion slowing down in demixing H–He mixtures within Jovian planets core or multiionic target such as Kapton.

  14. Multiple scattering in electron fluid and energy loss in multi-ionic targets

    Deutsch, C.; Tahir, N.A.; Barriga-Carrasco, M.; Ceban, V.; Fromy, P.; Gilles, D.; Leger, D.; Maynard, G.; Tashev, B.; Volpe, L.

    2014-01-01

    Extensions of the standard stopping model (SSM) for ion projectiles interacting with dense targets of timely concern for ICF and WDM are reviewed. They include multiple scattering on partially degenerate electrons, low velocity ion slowing down in demixing H–He mixtures within Jovian planets core or multiionic target such as Kapton

  15. Energy spectrum of charge carriers in TlIn{sub 1–x}Yb{sub x}Te{sub 2} solid solutions

    Aliev, F. F., E-mail: farzali@physics.ab.az [Azerbaijan National Academy of Sciences, Institute of Physics (Azerbaijan); Agaeva, U. M.; Zarbaliev, M. M., E-mail: zarbalievmm51@mail.ru [Sumqayit State University (Azerbaijan)

    2016-10-15

    The temperature dependences of the electrical conductivity σ(T), the Hall coefficient R(T), and the thermoelectric coefficient α(T) are investigated in TlIn{sub 1–x}Yb{sub x}Te{sub 2} (0 < x < 0.10) solid solutions at 80–1000K. From the kinetic parameters, the effective masses of electrons and holes are determined. The obtained experimental data on σ(T) and α(T) are interpreted within the context of a model with one and two types of charge carriers. It is established that, since x = 0.05, the TlIn{sub 1–x}Yb{sub x}Te{sub 2} solid solutions belong to the class of narrow-gap semiconductors that have high matrix elements of interaction.

  16. A Novel Approach to Neighborhood Fair Energy Trading in a Distribution Network of Multiple Microgrid Clusters

    Jadhav, Ashok Mohan; Patne, Nita Ravindra; Guerrero, Josep M.

    2018-01-01

    of their total surplus. To avoid the selfish behaviour of any buyer MG, an algorithm is used by the energy market operator which verifies the strategies submitted by buyer MGs before releasing set points to the generators. Apart from fairness and stability, the extensive numerical study confirms the ascendancy...... as a mediator between the trading parties. Depending on the priority factor, each buyer MG decides its strategy for energy demand from the surplus using a non-cooperative game theory based algorithm. The interests of seller MGs are protected by allowing them to decide the amount of energy they want to share out...

  17. Multiple calibration decomposition analysis: Energy use and carbon dioxide emissions in the Japanese economy, 1970-1995

    Okushima, Shinichiro; Tamura, Makoto

    2007-01-01

    The purpose of this paper is to present a new approach to evaluating structural change of the economy in a multisector general equilibrium framework. The multiple calibration technique is applied to an ex post decomposition analysis of structural change between periods, enabling the distinction between price substitution and technological change to be made for each sector. This approach has the advantage of sounder microtheoretical underpinnings when compared with conventional decomposition methods. The proposed technique is empirically applied to changes in energy use and carbon dioxide (CO 2 ) emissions in the Japanese economy from 1970 to 1995. The results show that technological change is of great importance for curtailing energy use and CO 2 emissions in Japan. Total CO 2 emissions increased during this period primarily because of economic growth, which is represented by final demand effects. On the other hand, the effects such as technological change for labor or energy mitigated the increase in CO 2 emissions

  18. Carrier-mediated transport of peptides by the kidney

    Skopicki, H.A.

    1988-01-01

    Small peptide transport was characterized to determine if: (1) Multiple carriers are present in the luminal membrane of renal proximal tubular cells; (2) Carrier-mediated peptide transport is limited by size; and (3) Gentamicin inhibits carrier-mediated reabsorption of peptides. Uptake of glycyl-[ 3 H]proline (Gly-Pro) into renal brush border membrane vesicles demonstrated a dual affinity carrier system. Whether multiple carriers are present was further investigated by characterizing the uptake of [ 3 H]pyroglutamyl-histidine. To determine if carrier-mediated transport of peptides is limited by size of the molecule, uptake of the hydrolytically resistant tripeptide, [ 3 H]pryroglutamyl-histidyl-tryptophan (pGlu-His-Trp), and tetrapeptide, [ 3 H]pyroglutamyl-histidyl-tryptophyl-serine (pGlu-His-Trp-Ser) were assessed. These data indicate: multiple carriers exist on the luminal membrane of renal proximal tubular cells for the transport of dipeptides, and tripeptide pGlu-His-Trp and the tetrapeptide pGlu-His-Trp-Ser are not taken up by a carrier-mediated mechanism, suggesting that the carrier may be limited by the size of the substrate

  19. Multiple environment single system quantum mechanical/molecular mechanical (MESS-QM/MM) calculations. 1. Estimation of polarization energies.

    Sodt, Alexander J; Mei, Ye; König, Gerhard; Tao, Peng; Steele, Ryan P; Brooks, Bernard R; Shao, Yihan

    2015-03-05

    In combined quantum mechanical/molecular mechanical (QM/MM) free energy calculations, it is often advantageous to have a frozen geometry for the quantum mechanical (QM) region. For such multiple-environment single-system (MESS) cases, two schemes are proposed here for estimating the polarization energy: the first scheme, termed MESS-E, involves a Roothaan step extrapolation of the self-consistent field (SCF) energy; whereas the other scheme, termed MESS-H, employs a Newton-Raphson correction using an approximate inverse electronic Hessian of the QM region (which is constructed only once). Both schemes are extremely efficient, because the expensive Fock updates and SCF iterations in standard QM/MM calculations are completely avoided at each configuration. They produce reasonably accurate QM/MM polarization energies: MESS-E can predict the polarization energy within 0.25 kcal/mol in terms of the mean signed error for two of our test cases, solvated methanol and solvated β-alanine, using the M06-2X or ωB97X-D functionals; MESS-H can reproduce the polarization energy within 0.2 kcal/mol for these two cases and for the oxyluciferin-luciferase complex, if the approximate inverse electronic Hessians are constructed with sufficient accuracy.

  20. Computation of Hydration Free Energies Using the Multiple Environment Single System Quantum Mechanical/Molecular Mechanical Method.

    König, Gerhard; Mei, Ye; Pickard, Frank C; Simmonett, Andrew C; Miller, Benjamin T; Herbert, John M; Woodcock, H Lee; Brooks, Bernard R; Shao, Yihan

    2016-01-12

    A recently developed MESS-E-QM/MM method (multiple-environment single-system quantum mechanical molecular/mechanical calculations with a Roothaan-step extrapolation) is applied to the computation of hydration free energies for the blind SAMPL4 test set and for 12 small molecules. First, free energy simulations are performed with a classical molecular mechanics force field using fixed-geometry solute molecules and explicit TIP3P solvent, and then the non-Boltzmann-Bennett method is employed to compute the QM/MM correction (QM/MM-NBB) to the molecular mechanical hydration free energies. For the SAMPL4 set, MESS-E-QM/MM-NBB corrections to the hydration free energy can be obtained 2 or 3 orders of magnitude faster than fully converged QM/MM-NBB corrections, and, on average, the hydration free energies predicted with MESS-E-QM/MM-NBB fall within 0.10-0.20 kcal/mol of full-converged QM/MM-NBB results. Out of five density functionals (BLYP, B3LYP, PBE0, M06-2X, and ωB97X-D), the BLYP functional is found to be most compatible with the TIP3P solvent model and yields the most accurate hydration free energies against experimental values for solute molecules included in this study.

  1. Meteorological evaluation of multiple reactor contamination probabilities for a Hanford Nuclear Energy Center

    Ramsdell, J.V.; Diebel, D.I.

    1978-03-01

    The conceptual Hanford energy center is composed of nuclear power plants, hence the name Hanford Nuclear Energy Center (HNEC). Previous topical reports have covered a variety of subjects related to the HNEC including: electric power transmission, fuel cycle, and heat disposal. This report discusses the probability that a radiation release from a single reactor in the HNEC would contaminate other facilities in the center. The risks, in terms of reliability of generation, of this potential contamination are examined by Clark and Dowis

  2. A multiple perspective modeling and simulation approach for renewable energy policy evaluation

    Alyamani, Talal M.

    Environmental issues and reliance on fossil fuel sources, including coal, oil, and natural gas, are the two most common energy issues that are currently faced by the United States (U.S.). Incorporation of renewable energy sources, a non-economical option in electricity generation compared to conventional sources that burn fossil fuels, single handedly promises a viable solution for both of these issues. Several energy policies have concordantly been suggested to reduce the financial burden of adopting renewable energy technologies and make such technologies competitive with conventional sources throughout the U.S. This study presents a modeling and analysis approach for comprehensive evaluation of renewable energy policies with respect to their benefits to various related stakeholders--customers, utilities, governmental and environmental agencies--where the debilitating impacts, advantages, and disadvantages of such policies can be assessed and quantified at the state level. In this work, a novel simulation framework is presented to help policymakers promptly assess and evaluate policies from different perspectives of its stakeholders. The proposed framework is composed of four modules: 1) a database that collates the economic, operational, and environmental data; 2) elucidation of policy, which devises the policy for the simulation model; 3) a preliminary analysis, which makes predictions for consumption, supply, and prices; and 4) a simulation model. After the validity of the proposed framework is demonstrated, a series of planned Florida and Texas renewable energy policies are implemented into the presented framework as case studies. Two solar and one energy efficiency programs are selected as part of the Florida case study. A utility rebate and federal tax credit programs are selected as part of the Texas case study. The results obtained from the simulation and conclusions drawn on the assessment of current energy policies are presented with respect to the

  3. Multiple timescale analysis and factor analysis of energy ecological footprint growth in China 1953-2006

    Chen Chengzhong; Lin Zhenshan

    2008-01-01

    Scientific analysis of energy consumption and its influencing factors is of great importance for energy strategy and policy planning. The energy consumption in China 1953-2006 is estimated by applying the energy ecological footprint (EEF) method, and the fluctuation periods of annual China's per capita EEF (EEF cpc ) growth rate are analyzed with the empirical mode decomposition (EMD) method in this paper. EEF intensity is analyzed to depict energy efficiency in China. The main timescales of the 37 factors that affect the annual growth rate of EEF cpc are also discussed based on EMD and factor analysis methods. Results show three obvious undulation cycles of the annual growth rate of EEF cpc , i.e., 4.6, 14.4 and 34.2 years over the last 53 years. The analysis findings from the common synthesized factors of IMF1, IMF2 and IMF3 timescales of the 37 factors suggest that China's energy policy-makers should attach more importance to stabilizing economic growth, optimizing industrial structure, regulating domestic petroleum exploitation and improving transportation efficiency

  4. Unique effects of energy versus estrogen deficiency on multiple components of bone strength in exercising women.

    Southmayd, E A; Mallinson, R J; Williams, N I; Mallinson, D J; De Souza, M J

    2017-04-01

    Many female athletes are energy and/or estrogen deficient, but the independent effects on bone health have not been isolated. Energy deficiency was detrimental at the tibia while estrogen deficiency was detrimental at the radius. Nutrition must be considered alongside menstrual recovery when addressing compromised bone health in female athletes. The purpose of this study was to describe volumetric bone mineral density (vBMD), bone geometry, and estimated bone strength in exercising women (n = 60) grouped according to energy status (energy replete (EnR: n = 30) vs. energy deficient (EnD: n = 30)) and estrogen status (estrogen replete (E 2 R: n = 33) vs. estrogen deficient (E 2 D: n = 27)), resulting in four distinct groups: EnR + E 2 R (n = 17), EnR + E 2 D (n = 13), EnD + E 2 R (n = 16), EnD + E 2 D (n = 14). Energy status was determined using the ratio of measured to predicted resting energy expenditure (mREE/pREE). Estrogen status was based on self-reported menstrual status confirmed by daily evaluation of urinary estrone-1-glucoronide (E1G), pregnanediol glucuronide (PdG), and luteinizing hormone (LH). Eumenorrheic women were considered E 2 R, amenorrheic women were E 2 D, and oligomenorrheic women were categorized based on history of menses in the past year. Bone was assessed using peripheral quantitative computed tomography (pQCT). EnD women exhibited lower total vBMD, trabecular vBMD, cortical area, and BSI at the distal tibia and lower total vBMD, smaller cortical area and cortical thickness, and larger endosteal circumference at the proximal tibia compared to EnR women (p < 0.042). E 2 D women had lower total and cortical vBMD, larger total and trabecular area, and lower BSI at the distal radius and lower cortical vBMD at the proximal radius compared to E 2 R women (p < 0.023). Energy and estrogen interacted to affect total and trabecular area at the distal tibia (p < 0.021). Efforts to correct energy deficiency, which in turn may

  5. Determination of Cost-Effective Energy Efficiency Measures in Buildings with the Aid of Multiple Indices

    Theodoros Zachariadis

    2018-01-01

    Full Text Available Energy refurbishments of buildings can substantially contribute to economy-wide energy efficiency improvements, leading to decarbonisation and additional sustainability benefits. Prioritising the most economically promising investments is not straightforward because apart from cost-effectiveness calculations, several real-world constraints have to be taken into account. This paper describes an approach to assess the economically viable energy efficiency potential in the building sector of the Mediterranean island of Cyprus, with a combination of detailed engineering modelling, cost-effectiveness calculations and real-world considerations of budgetary, technical, behavioural and market constraints. We examine diverse cost-effectiveness indices and come up with a proposal for prioritising specific energy investments such as the installation of heat pumps, insulation of roofs, and replacement of lighting and electronic equipment—without however ignoring other measures that may be economically less favourable but can realistically be implemented in a limited number of buildings. Finally we address the governance of energy efficiency policies, focusing on weaknesses of the current regulatory environment in Cyprus, which can be generalised for many other countries facing similar dilemmas.

  6. Total-Factor Energy Efficiency (TFEE Evaluation on Thermal Power Industry with DEA, Malmquist and Multiple Regression Techniques

    Jin-Peng Liu

    2017-07-01

    Full Text Available Under the background of a new round of power market reform, realizing the goals of energy saving and emission reduction, reducing the coal consumption and ensuring the sustainable development are the key issues for thermal power industry. With the biggest economy and energy consumption scales in the world, China should promote the energy efficiency of thermal power industry to solve these problems. Therefore, from multiple perspectives, the factors influential to the energy efficiency of thermal power industry were identified. Based on the economic, social and environmental factors, a combination model with Data Envelopment Analysis (DEA and Malmquist index was constructed to evaluate the total-factor energy efficiency (TFEE in thermal power industry. With the empirical studies from national and provincial levels, the TFEE index can be factorized into the technical efficiency index (TECH, the technical progress index (TPCH, the pure efficiency index (PECH and the scale efficiency index (SECH. The analysis showed that the TFEE was mainly determined by TECH and PECH. Meanwhile, by panel data regression model, unit coal consumption, talents and government supervision were selected as important indexes to have positive effects on TFEE in thermal power industry. In addition, the negative indexes, such as energy price and installed capacity, were also analyzed to control their undesired effects. Finally, considering the analysis results, measures for improving energy efficiency of thermal power industry were discussed widely, such as strengthening technology research and design (R&D, enforcing pollutant and emission reduction, distributing capital and labor rationally and improving the government supervision. Relative study results and suggestions can provide references for Chinese government and enterprises to enhance the energy efficiency level.

  7. Matches, Mismatches, and Methods: Multiple-View Workflows for Energy Portfolio Analysis.

    Brehmer, Matthew; Ng, Jocelyn; Tate, Kevin; Munzner, Tamara

    2016-01-01

    The energy performance of large building portfolios is challenging to analyze and monitor, as current analysis tools are not scalable or they present derived and aggregated data at too coarse of a level. We conducted a visualization design study, beginning with a thorough work domain analysis and a characterization of data and task abstractions. We describe generalizable visual encoding design choices for time-oriented data framed in terms of matches and mismatches, as well as considerations for workflow design. Our designs address several research questions pertaining to scalability, view coordination, and the inappropriateness of line charts for derived and aggregated data due to a combination of data semantics and domain convention. We also present guidelines relating to familiarity and trust, as well as methodological considerations for visualization design studies. Our designs were adopted by our collaborators and incorporated into the design of an energy analysis software application that will be deployed to tens of thousands of energy workers in their client base.

  8. Characterizing the Effective Bandwidth of Nonlinear Vibratory Energy Harvesters Possessing Multiple Stable Equilibria

    Panyam Mohan Ram, Meghashyam

    In the last few years, advances in micro-fabrication technologies have lead to the development of low-power electronic devices spanning critical fields related to sensing, data transmission, and medical implants. Unfortunately, effective utilization of these devices is currently hindered by their reliance on batteries. In many of these applications, batteries may not be a viable choice as they have a fixed storage capacity and need to be constantly replaced or recharged. In light of such challenges, several novel concepts for micro-power generation have been recently introduced to harness, otherwise, wasted ambient energy from the environment and maintain these low-power devices. Vibratory energy harvesting is one such concept which has received significant attention in recent years. While linear vibratory energy harvesters have been well studied in the literature and their performance metrics have been established, recent research has focused on deliberate introduction of stiffness nonlinearities into the design of these devices. It has been shown that, nonlinear energy harvesters have a wider steady-state frequency bandwidth as compared to their linear counterparts, leading to the premise that they can used to improve performance, and decrease sensitivity to variations in the design and excitation parameters. This dissertation aims to investigate this premise by developing an analytical framework to study the influence of stiffness nonlinearities on the performance and effective bandwidth of nonlinear vibratory energy harvesters. To achieve this goal, the dissertation is divided into three parts. The first part investigates the performance of bi-stable energy harvesters possessing a symmetric quartic potential energy function under harmonic excitations and carries out a detailed analysis to define their effective frequency bandwidth. The second part investigates the relative performance of mono- and bi-stable energy harvesters under optimal electric loading

  9. Energy-Efficient Deadline-Aware Data-Gathering Scheme Using Multiple Mobile Data Collectors.

    Dasgupta, Rumpa; Yoon, Seokhoon

    2017-04-01

    In wireless sensor networks, the data collected by sensors are usually forwarded to the sink through multi-hop forwarding. However, multi-hop forwarding can be inefficient due to the energy hole problem and high communications overhead. Moreover, when the monitored area is large and the number of sensors is small, sensors cannot send the data via multi-hop forwarding due to the lack of network connectivity. In order to address those problems of multi-hop forwarding, in this paper, we consider a data collection scheme that uses mobile data collectors (MDCs), which visit sensors and collect data from them. Due to the recent breakthroughs in wireless power transfer technology, MDCs can also be used to recharge the sensors to keep them from draining their energy. In MDC-based data-gathering schemes, a big challenge is how to find the MDCs' traveling paths in a balanced way, such that their energy consumption is minimized and the packet-delay constraint is satisfied. Therefore, in this paper, we aim at finding the MDCs' paths, taking energy efficiency and delay constraints into account. We first define an optimization problem, named the delay-constrained energy minimization (DCEM) problem, to find the paths for MDCs. An integer linear programming problem is formulated to find the optimal solution. We also propose a two-phase path-selection algorithm to efficiently solve the DCEM problem. Simulations are performed to compare the performance of the proposed algorithms with two heuristics algorithms for the vehicle routing problem under various scenarios. The simulation results show that the proposed algorithms can outperform existing algorithms in terms of energy efficiency and packet delay.

  10. Higher moments of net kaon multiplicity distributions at RHIC energies for the search of QCD Critical Point at STAR

    Sarkar Amal

    2013-11-01

    Full Text Available In this paper we report the measurements of the various moments mean (M, standard deviation (σ skewness (S and kurtosis (κ of the net-Kaon multiplicity distribution at midrapidity from Au+Au collisions at √sNN = 7.7 to 200 GeV in the STAR experiment at RHIC in an effort to locate the critical point in the QCD phase diagram. These moments and their products are related to the thermodynamic susceptibilities of conserved quantities such as net baryon number, net charge, and net strangeness as also to the correlation length of the system. A non-monotonic behavior of these variable indicate the presence of the critical point. In this work we also present the moments products Sσ, κσ2 of net-Kaon multiplicity distribution as a function of collision centrality and energies. The energy and the centrality dependence of higher moments of net-Kaons and their products have been compared with it0s Poisson expectation and with simulations from AMPT which does not include the critical point. From the measurement at all seven available beam energies, we find no evidence for a critical point in the QCD phase diagram for √sNN below 200 GeV.

  11. Variation of multiplicity and transverse energy flow with W2 and Q2 in deep inelastic scattering at HERA

    Lohmander, H.

    1995-04-01

    Charged particle and transverse energy flow for deep inelastic ep scattering at HERA have been investigated in the hadronic center of mass systems as a function of pseudorapidity η* in different W 2 and Q 2 intervals. In addition, the mean charged particle multiplicity ch > and the mean transverse energy * Τ > as a function of W 2 and Q 2 have been studied. The measurements were made in the kinematic region 85 2 2 . The ch > was found to increase with increasing W 2 at fixed Q 2 but did not show any significant dependence on Q 2 at fixed W 2 . The best description of the mean charged multiplicity is given by ch >=a+b·ln(W 2 /GeV 2 ) with a=-1.38±0.07 and b=0.93±0.05. The * Τ > increased both with increasing W 2 at fixed Q 2 and with increasing Q 2 at fixed W 2 . The mean transverse energy is described by * Τ >=a+b·ln(W 2 /GeV 2 )+c·ln (Q 2 /GeV 2 )GeV with a=-5.93±0.07, b=1.28±0.06 and c=0.69±0.02. Different QCD models have been compared with data. Only the Color Dipole Model, as implemented in the Monte Carlo program Ariadne, describes the data satisfactorily. 29 refs

  12. Energy Dependence of Particle Multiplicities in Central Au+Au Collisions

    Back, B. B.; Baker, M. D.; Barton, D. S.; Betts, R. R.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Corbo, J.; Decowski, M. P.; Garcia, E.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Hamblen, J.; Henderson, C.; Hicks, D.; Hofman, D.; Hollis, R. S.; Hołyński, R.; Holzman, B.; Iordanova, A.; Johnson, E.; Kane, J.; Katzy, J.; Khan, N.; Kucewicz, W.; Kulinich, P.; Kuo, C. M.; Lin, W. T.; Manly, S.; McLeod, D.; Michałowski, J.; Mignerey, A.; Mülmenstädt, J.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Rafelski, M.; Rbeiz, M.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sagerer, J.; Sarin, P.; Sawicki, P.; Skulski, W.; Steadman, S. G.; Steinberg, P.; Stephans, G. S.; Stodulski, M.; Sukhanov, A.; Tang, J.-L.; Teng, R.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Verdier, R.; Wadsworth, B.; Wolfs, F. L.; Wosiek, B.; Woźniak, K.; Wuosmaa, A. H.; Wysłouch, B.

    2002-01-01

    We present the first measurement of the pseudorapidity density of primary charged particles in Au+Au collisions at (sNN) = 200 GeV. For the 6% most central collisions, we obtain dNch/dη\\|\\|η\\|<1 = 650+/-35(syst). Compared to collisions at (sNN) = 130 GeV, the highest energy studied previously, an increase by a factor of 1.14+/-0.05 at 90% confidence level, is found. The energy dependence of the pseudorapidity density is discussed in comparison with data from proton-induced collisions and theoretical predictions.

  13. Performance of JEF2.2 based continuous energy cross sections in predicting the multiplication factor of critical systems

    John, T.M.; de Leege, P.F.A.; Hoogenboom, J.E.

    1996-01-01

    The continuous energy representation of cross sections for neutronics calculations avoids the requirement of resonance self shielding and the assumptions about the neutron spectrum used for weighing cross sections, required in the preparation of a multigroup cross sections library. The cross sections library prepared for a particular temperature of the nuclide is valid irrespective of the environment of the nuclide and can be used in calculations for many types of reactors. It is comparatively easier to incorporate them in Monte Carlo simulation of neutron transport. The Monte Carlo code MCNP is capable of using a continuous energy representation of nuclear cross sections in simulation of neutron or photon transport. The ACER module of NJOY is able to generate the continuous energy cross section of any nuclide in a format that can be used by MCNP, from any evaluated data file in ENDF/B format. Continuous energy cross sections prepared from the evaluated data file JEF2.2 was used to analyse some standard critical benchmarks and also the critical configuration of the HOR, a 2 MW research reactor at Delft, the Netherlands. Results show that continuous energy cross sections prepared from JEF2.2 evaluated file predicts the multiplication factor of critical systems very close to unity. (author). 6 refs., 2 tabs., 1 fig

  14. Attainability and minimum energy of multiple-stage cascade membrane Systems

    Alshehri, Ali; Lai, Zhiping

    2015-01-01

    : View the MathML sourceSn=S1, View the MathML sourceγn=γ1, where n is the number of stages. The minimum energy consumption of a multi-stage membrane process is primarily determined by the membrane selectivity and recycle ratio. A low recycle ratio can

  15. Using Flow Electrodes in Multiple Reactors in Series for Continuous Energy Generation from Capacitive Mixing

    Hatzell, Marta C.

    2014-12-09

    Efficient conversion of “mixing energy” to electricity through capacitive mixing (CapMix) has been limited by low energy recoveries, low power densities, and noncontinuous energy production resulting from intermittent charging and discharging cycles. We show here that a CapMix system based on a four-reactor process with flow electrodes can generate constant and continuous energy, providing a more flexible platform for harvesting mixing energy. The power densities were dependent on the flow-electrode carbon loading, with 5.8 ± 0.2 mW m–2 continuously produced in the charging reactor and 3.3 ± 0.4 mW m–2 produced in the discharging reactor (9.2 ± 0.6 mW m–2 for the whole system) when the flow-electrode carbon loading was 15%. Additionally, when the flow-electrode electrolyte ion concentration increased from 10 to 20 g L–1, the total power density of the whole system (charging and discharging) increased to 50.9 ± 2.5 mW m–2.

  16. Probing the Free Energy Landscape of the FBP28 WW Domain Using Multiple Techniques

    Periole, Xavier; Allen, Lucy R.; Tamiola, Kamil; Mark, Alan E.; Paci, Emanuele

    The free-energy landscape of a small protein, the FBP 28 WW domain, has been explored using molecular dynamics (MD) simulations with alternative descriptions of the molecule. The molecular models used range from coarse-grained to all-atom with either an implicit or explicit treatment of the solvent.

  17. Attainability and minimum energy of multiple-stage cascade membrane Systems

    Alshehri, Ali

    2015-08-12

    Process design and simulation of multi-stage membrane systems have been widely studied in many gas separation systems. However, general guidelines have not been developed yet for the attainability and the minimum energy consumption of a multi-stage membrane system. Such information is important for conceptual process design and thus it is the topic of this work. Using a well-mixed membrane model, it was determined that the attainability curve of multi-stage systems is defined by the pressure ratio and membrane selectivity. Using the constant recycle ratio scheme, the recycle ratio can shift the attainability behavior between single-stage and multi-stage membrane systems. When the recycle ratio is zero, all of the multi-stage membrane processes will decay to a single-stage membrane process. When the recycle ratio approaches infinity, the required selectivity and pressure ratio reach their absolute minimum values, which have a simple relationship with that of a single-stage membrane process, as follows: View the MathML sourceSn=S1, View the MathML sourceγn=γ1, where n is the number of stages. The minimum energy consumption of a multi-stage membrane process is primarily determined by the membrane selectivity and recycle ratio. A low recycle ratio can significantly reduce the required membrane selectivity without substantial energy penalty. The energy envelope curve can provide a guideline from an energy perspective to determine the minimum required membrane selectivity in membrane process designs to compete with conventional separation processes, such as distillation.

  18. Mass distribution and multiple fragmentation events in high energy cluster-cluster collisions: evidence for a predicted phase transition

    Farizon, B.; Farizon, M.; Gaillard, M.J.; Genre, R.; Louc, S.; Martin, J.; Senn, G.; Scheier, P.; Maerk, T.D.

    1996-09-01

    Fragment size distributions including multiple fragmentation events have been measured for high energy H 25 + cluster ions (60 keV/amu) colliding with a neutral C 60 target. In contrast to earlier collision experiments with a helium target the present studies do not show a U-shaped fragment mass distribution, but a single power-law falloff with increasing fragment mass. This behaviour is similar to what is known for the intermediate regime in nuclear collision physics and thus confirms a recently predicted scaling from nuclear to molecular collisions

  19. Effects of Isospin on Pre-scission Particle Multiplicity of Heavy Systems and Its Excitation Energy Dependence

    YE Wei; CHEN Na

    2004-01-01

    Isospin effects on particle emission of fissioning isobaric sources 202Fr, 202po, 202Tl and isotopic sources 189,202,212Po, and its dependence on the excitation energy are studied via Smoluchowski equations. It is shown that with increasing the isospin of fissioning systems, charged-particle emission is not sensitive to the strength of nuclear dissipation. In addition, we have found that increasing the excitation energy not only increases the influence of nuclear dissipation on particle emission but also greatly enhances the sensitivity of the emission of pre-scission neutrons or charged particles to the isospin of the system. Therefore, in order to extract dissipation strength more accurately by taking light particle multiplicities it is important to choose both a highly excited compound nucleus and a proper kind of particles for systems with different isospins.

  20. Estimating the two-particle K-matrix for multiple partial waves and decay channels from finite-volume energies

    Colin Morningstar

    2017-11-01

    Full Text Available An implementation of estimating the two-to-two K-matrix from finite-volume energies based on the Lüscher formalism and involving a Hermitian matrix known as the “box matrix” is described. The method includes higher partial waves and multiple decay channels. Two fitting procedures for estimating the K-matrix parameters, which properly incorporate all statistical covariances, are discussed. Formulas and software for handling total spins up to S=2 and orbital angular momenta up to L=6 are obtained for total momenta in several directions. First tests involving ρ-meson decay to two pions include the L=3 and L=5 partial waves, and the contributions from these higher waves are found to be negligible in the elastic energy range.

  1. Neutron multiplicity for neutron induced fission of 235U, 238U, and 239Pu as a function of neutron energy

    Zucker, M.S.; Holden, N.E.

    1986-01-01

    Recent development in the theory and practice of neutron correlation (''coincidence'') counting require knowledge of the higher factorial moments of the P/sub ν/ distribution (the probability that (ν) neutrons are emitted in a fission) for the case where the fission is induced by bombarding neutrons of more than thermal energies. In contrast to the situation with spontaneous and thermal neutron induced fission, where with a few exceptions the P/sub ν/ is reasonably well known, in the fast neutron energy region, almost no information is available concerning the multiplicity beyond the average value, [ν], even for the most important nuclides. The reason for this is the difficulty of such experiments, with consequent statistically poor and physically inconsistent results

  2. Quantum electrodynamics of the internal source x-ray holographies: Bremsstrahlung, fluorescence, and multiple-energy x-ray holography

    Miller, G.A.; Sorensen, L.B.

    1997-01-01

    Quantum electrodynamics (QED) is used to derive the differential cross sections measured in the three new experimental internal source ensemble x-ray holographies: bremsstrahlung (BXH), fluorescence (XFH), and multiple-energy (MEXH) x-ray holography. The polarization dependence of the BXH cross section is also obtained. For BXH, we study analytically and numerically the possible effects of the virtual photons and electrons which enter QED calculations in summing over the intermediate states. For the low photon and electron energies used in the current experiments, we show that the virtual intermediate states produce only very small effects. This is because the uncertainty principle limits the distance that the virtual particles can propagate to be much shorter than the separation between the regions of high electron density in the adjacent atoms. We also find that using the asymptotic form of the scattering wave function causes about a 5 10% error for near forward scattering. copyright 1997 The American Physical Society

  3. Multiplicity and correlated energy of gamma rays emitted in the spontaneous fission of Californium-252

    Brunson, G.S. Jr.

    1982-06-01

    An array of eight high-speed plastic scintillation detectors has been used to infer a mathematical model for the emission multipliciy of prompt gammas in the spontaneous fission of 252 Cf. Exceptional time resolution and coincidence capability permitted the separation of gammas from fast neutrons over a flight path of approximately 10 cm. About 20 different distribution models were tested. The average energy of the prompt gammas is inversely related to the number emitted; however, this inverse relationship is not strong and the total gamma energy does increase with increasing gamma number. An extension of the experiment incorporated a lithium-drifted germanium gamma spectrometer that resolved nearly 100 discrete gammas associated with fission. Of these gammas, some were preferentially associated with fission in which few gammas were emitted. Certain others were more frequent when many gammas were emitted. Results are presented

  4. Analysis of pp scattering at the CERN ISR energies in the multiple Regge pole model

    Bugrij, A.I.; Kobylinsky, N.A.

    1976-01-01

    The simple Regge model is suggested for describing data on proton-proton elastic scattering at high energies. The simplest variant of the Regge model can be formulated as a sum of two pomerons, the first being a moving double pole and the second - a fixed simple pole. Comparison with known data is given. The model gives an infinite rise of the total cross section of pp-scattering. The differential cross section changes slowly with energy. The models of two pomerons reproduce many features of the geometric scaling, in particular, the shift of the dip and rise of scattering total cross section at the second maximum. The considered model is rather simple and is well consistent with experiment

  5. Evaluating information in multiple horizon forecasts. The DOE's energy price forecasts

    Sanders, Dwight R.; Manfredo, Mark R.; Boris, Keith

    2009-01-01

    The United States Department of Energy's (DOE) quarterly price forecasts for energy commodities are examined to determine the incremental information provided at the one-through four-quarter forecast horizons. A direct test for determining information content at alternative forecast horizons, developed by Vuchelen and Gutierrez [Vuchelen, J. and Gutierrez, M.-I. 'A Direct Test of the Information Content of the OECD Growth Forecasts.' International Journal of Forecasting. 21(2005):103-117.], is used. The results suggest that the DOE's price forecasts for crude oil, gasoline, and diesel fuel do indeed provide incremental information out to three-quarters ahead, while natural gas and electricity forecasts are informative out to the four-quarter horizon. In contrast, the DOE's coal price forecasts at two-, three-, and four-quarters ahead provide no incremental information beyond that provided for the one-quarter horizon. Recommendations of how to use these results for making forecast adjustments is also provided. (author)

  6. A simple method to produce quasi-simultaneous multiple energy helium implantation

    Paszti, F.; Fried, M.; Manuaba, A.; Mezey, G.; Kotai, E.; Lohner, T.

    1982-11-01

    If a monoenergetic ion beam is bombarding a target through an absorber foil tilted continuously (i.e. its effective thickness changing continuously), the depth distribution of the implanted ions in the sample depends on the way the absorber is moving. The present paper describes a way of absorber tilting for obtaining a uniform depth distribution and its experimental verification in the case of MeV energy helium ions implanted into aluminium target. (author)

  7. Improving Australia's renewable energy project policy and planning: A multiple stakeholder analysis

    Martin, Nigel; Rice, John

    2015-01-01

    Renewable Energy (RE) is part of Australia's and the world's energy supply matrix with over A$100 billion spent annually on RE projects since 2007. Businesses seeking to invest in RE projects, particularly in the wind and solar energy sectors, may face an onerous collection of planning approvals and permitting processes that impede investment and implementation. In this study, we draw on international and domestic stakeholder inputs to a governmental inquiry in Australia to show how RE projects might be approved in shortened timeframes with reduced associated costs. The process mapping and stakeholder analysis demonstrates that RE supply projects can benefit from standardized approval processes and documentation, a 360° deep engagement with stakeholders, and expanded electricity grid access in resource areas, augmented through supportive public policy and planning frameworks. In addition, stakeholder objections to project approval and implementation streamlining were used to contrast the efficacy of the proposed changes in policy. -- Highlights: •Highlights the over A$200 billion spent annually on global RE projects. •Describes a typical two stage, multi-layered governance RE project approval process. •Exposes long 3 year and multi-million dollar cost approvals for RE projects. •Identifies multi-million dollar remote grid connections as an RE project impediment. •Outlines RE project policy and guidelines shortcomings and proposed improvements

  8. Energy dependence of the multiplicity analysis of quark-diquark jets

    Biswal, K; Panda, A R; Parida, B K

    1980-01-01

    Under the assumption of hard scattering, multiplicity analysis of quark-diquark jets is made in a model analogous to the quark-cascade- jet production model developed earlier. In the present approach the diquark is treated as a coherent object consisting of the two quarks which remain after the hard scattering. This is assumed to produce a baryon and an antiquark in the first stage of its fragmentation. The resulting quark-antiquark pair then hadronises as per the cascade model. This picture of quark-diquark fragmentation is adequately supported by the observations made in recent ISR experiments at CERN. The above technique is applied to weak, electromagnetic and strong processes involving quark-diquark hadronisation in a unified manner and with fair agreement with the experimental results. (0 refs).

  9. Charge-sign-clustering observed in high-multiplicity, high-energy heavy-ion collisions

    Takahashi, Y.; Gregory, J.C.; Hayashi, T.

    1989-01-01

    Charge-sign distribution in 200 GeV/amu heavy-ion collisions is studied with the Magnetic-Interferometric-Emulsion-Chamber (MAGIC) for central collision events in 16 O + Pb and 32 S + Pb interactions. Charge-sign clustering is observed in most of the fully-analyzed events. A statistical 'run-test' is performed for each measured event, which shows significant deviation from a Gaussian distribution (0,1) expected for random-charge distribution. Candidates of charge clusters have 5 - 10 multiplicity of like-sign particles, and are often accompanied by opposite-sign clusters. Observed clustering of identical charges is more significant in the fragmentation region than in the central region. Two-particle Bose-Einstein interference and other effects are discussed for the run-test examination. (author)

  10. Analytical calculations of multiple scattering for high energy photons and neutrons

    Thoe, R.S.

    1994-04-01

    Radiography of large dense objects often require the use of highly penetrating radiation. For example, a couple of centimeters of steel attenuates 50 keV x-rays by a factor of approximately 10 -14 whereas this same amount of steel would attenuate a 500 keV photon beam by only a factor of about 0.25. However, this increase in penetrating power comes with a price. In the case of x-radiation there are two bills to pay: (1) For projection radiography, this increase in penetration directly causes a corresponding decrease in resolution. (2) This increase in penetration occurs in a region where the interaction of radiation and matter is changing from absorption to scattering. In the above example the fraction of scattering goes from about 0.1 at 50 keV to over 0.99 at 500 keV. These scattered photons can significantly degrade contrast. In order to overcome some of these difficulties, radiography using scattered photons has been studied by myself and numerous other authors. In all the above cases, calculation of the intensity of scattered radiation is of primary importance. In cases where scattering is probable, multiple scattering can also be probable. Calculations of multiple scattering are generally very difficult and usually require the use of extremely sophisticated Monte Carlo simulations. It is not unusual for these calculations to require several hours of CPU time on some of the worlds largest and fastest supercomputers. In this paper I will present an alternative approach. I will present an analytical solution to the equations of double scattering, and show how this solution can extended to the case of higher order scattering. Finally, I will give numerical examples of these solutions and compare them to solutions obtained by Monte Carlo simulations

  11. Invited Article: Multiple-octave spanning high-energy mid-IR supercontinuum generation in bulk quadratic nonlinear crystals

    Binbin Zhou

    2016-08-01

    Full Text Available Bright and broadband coherent mid-IR radiation is important for exciting and probing molecular vibrations. Using cascaded nonlinearities in conventional quadratic nonlinear crystals like lithium niobate, self-defocusing near-IR solitons have been demonstrated that led to very broadband supercontinuum generation in the visible, near-IR, and short-wavelength mid-IR. Here we conduct an experiment where a mid-IR crystal is pumped in the mid-IR. The crystal is cut for noncritical interaction, so the three-wave mixing of a single mid-IR femtosecond pump source leads to highly phase-mismatched second-harmonic generation. This self-acting cascaded process leads to the formation of a self-defocusing soliton at the mid-IR pump wavelength and after the self-compression point multiple octave-spanning supercontinua are observed. The results were recorded in a commercially available crystal LiInS2 pumped in the 3-4 μm range with 85 fs 50 μJ pulse energy, with the broadest supercontinuum covering 1.6-7.0 μm. We measured up 30 μJ energy in the supercontinuum, and the energy promises to scale favorably with an increased pump energy. Other mid-IR crystals can readily be used as well to cover other pump wavelengths and target other supercontinuum wavelength ranges.

  12. The effects of degeneracy of the carrier ensemble on the energy loss rate and the high field mobility characteristics under the conditions of low lattice temperatures

    Basu, A.; Das, B.; Middya, T.R.; Bhattacharya, D.P.

    2017-01-01

    The rate of loss of energy of the non-equilibrium electrons to the acoustic mode lattice vibration in a degenerate semiconductor is obtained under the condition, when the lattice temperature is low enough, so that the traditional approximations like the elastic nature of the electron-phonon collisions and the truncation of the phonon distribution to the equipartition law are not valid any more. Using the results of the energy loss rate, the non-ohmic mobility is then calculated. Evaluating the loss rate and the non-ohmic mobility in degenerate samples of Si and Ge we find that significant changes in both the characteristics have been effected compared to that in the non-degenerate samples, in the regime of lower energy and for relatively lower fields. The effected changes are more significant the lower the lattice temperature is.

  13. The effect of energy distribution of external source on source multiplication in fast assemblies

    Karam, R.A.; Vakilian, M.

    1976-02-01

    The essence of this study is the effect of energy distribution of a source on the detection rate as a function of K effective in fast assemblies. This effectiveness, as a function of K was studied in a fission chamber, using the ABN cross-section set and Mach 1 code. It was found that with a source which has a fission spectrum, the reciprocal count rate versus mass relationship is linear down to K effective 0.59. For a thermal source, the linearity was never achieved. (author)

  14. Duchenne muscular dystrophy carriers

    Matsumura, K.; Nakano, I.

    1989-01-01

    By means of magnetic resonance imaging (MRI), the proton spin-lattice relaxation times (T1 values) of the skeletal muscles were measured in Duchenne muscular dystrophy (DMD) carriers and normal controls. The bound water fraction (BWF) was calculated from the T1 values obtained, according to the fast proton diffusion model. In the DMD carriers, T1 values of the gluteus maximus and quadriceps femoris muscles were significantly higher, and BWFs of these muscles were significantly lower than in normal control. Degenerative muscular changes accompanied by interstitial edema were presumed responsible for this abnormality. No correlation was observed between the muscle T1 and serum creatine kinase values. The present study showed that MRI could be a useful method for studying the dynamic state of water in both normal and pathological skeletal muscles. Its possible utility for DMD carrier detection was discussed briefly. (orig.)

  15. Peripheral collisions in Ar induced reactions between 27 and 44 A.MeV: study of energy dissipation by measuring the correlated neutron multiplicities

    Guerreau, D.; Doubre, H.; Galin, J.; Pouthas, J.; Jahnke, U.; Jiang, D.X.; Lott, B.; Jacquet, D.

    1988-01-01

    A 4 π detector measuring the neutron multiplicities has been used to investigate the energy dissipation during peripheral collisions in Ar induced reactions around the Fermi Energy. Besides the persistance of direct transfer reactions for the most peripheral collisions, there are strong evidences for the occurrence of quite large energy dissipation, a clear signature for the one body friction to still play a major role at these intermediate energies

  16. J/ψ production as a function of charged particle multiplicity in proton + proton collisions at LHC energies

    Thakur, Dhananjaya; De, Sudipan; Sahoo, Raghunath; Dansana, Soumya

    2017-01-01

    In high energy proton-proton collisions the total event multiplicity can have a substantial contribution from Multi-Parton Interactions (MPI), which is an Underlying Event observable. The sum of all processes that build up the final hadronic state in a collision is referred as the Underlying Event (UE). The Underlying Event includes fragmentation of beam remnant, multi-partonic interactions, and initial and final state radiation (ISR/FSR) associated with each interactions. In MPI, several interactions at the partonic level occurs in a single p+p collision, that leads to a strong dependence of particle production on total event multiplicity. MPI are commonly used to describe the soft underlying events such as the production of light quarks and gluons. But it is observed that it can also contribute on the hard and semi-hard scale such as the production of particles containing heavy quarks like J/ψ, open heavy flavors etc. This contribution become more and more relevant with increasing energy

  17. Multiple regression analysis in modelling of carbon dioxide emissions by energy consumption use in Malaysia

    Keat, Sim Chong; Chun, Beh Boon; San, Lim Hwee; Jafri, Mohd Zubir Mat

    2015-04-01

    Climate change due to carbon dioxide (CO2) emissions is one of the most complex challenges threatening our planet. This issue considered as a great and international concern that primary attributed from different fossil fuels. In this paper, regression model is used for analyzing the causal relationship among CO2 emissions based on the energy consumption in Malaysia using time series data for the period of 1980-2010. The equations were developed using regression model based on the eight major sources that contribute to the CO2 emissions such as non energy, Liquefied Petroleum Gas (LPG), diesel, kerosene, refinery gas, Aviation Turbine Fuel (ATF) and Aviation Gasoline (AV Gas), fuel oil and motor petrol. The related data partly used for predict the regression model (1980-2000) and partly used for validate the regression model (2001-2010). The results of the prediction model with the measured data showed a high correlation coefficient (R2=0.9544), indicating the model's accuracy and efficiency. These results are accurate and can be used in early warning of the population to comply with air quality standards.

  18. Vision of future energy networks - Final report; Vision of future energy networks - Schlussbericht

    Froehlich, K.; Andersson, G.

    2008-07-01

    In the framework of the project 'Vision of Future Networks', models and methods have been developed that enable a greenfield approach for energy systems with multiple energy carriers. Applying a greenfield approach means that no existing infrastructure is taken into account when designing the energy system, i.e. the system is virtually put up on a green field. The developed models refer to the impacts of energy storage on power systems with stochastic generation, to the integrated modelling and optimization of multi-carrier energy systems, to reliability considerations of future energy systems as well as to possibilities of combined transmission of multiple energy carriers. Key concepts, which have been developed in the framework of this project, are the Energy Hub (for the conversion and storage of energy) and the Energy Interconnector (for energy transmission). By means of these concepts, it is possible to design structures for future energy systems being able to cope with the growing requirements regarding energy supply. (author)

  19. Natural carriers in bioremediation: A review

    Anna Dzionek

    2016-09-01

    Full Text Available Bioremediation of contaminated groundwater or soil is currently the cheapest and the least harmful method of removing xenobiotics from the environment. Immobilization of microorganisms capable of degrading specific contaminants significantly promotes bioremediation processes, reduces their costs, and also allows for the multiple use of biocatalysts. Among the developed methods of immobilization, adsorption on the surface is the most common method in bioremediation, due to the simplicity of the procedure and its non-toxicity. The choice of carrier is an essential element for successful bioremediation. It is also important to consider the type of process (in situ or ex situ, type of pollution, and properties of immobilized microorganisms. For these reasons, the article summarizes recent scientific reports about the use of natural carriers in bioremediation, including efficiency, the impact of the carrier on microorganisms and contamination, and the nature of the conducted research.

  20. Carbon: Hydrogen carrier or disappearing skeleton?

    De Jong, K.P.; Van Wechem, H.M.H.

    1994-01-01

    The use of liquid hydrocarbons as energy carriers implies the use of carbon as a carrier for hydrogen to facilitate hydrogen transport and storage. The current trend for liquid energy carriers used in the transport sector is to maximize the load of hydrogen on the carbon carrier. The recently developed Shell Middle Distillate Hydrogenation process for the manufacture of high quality diesel from aromatic refinery streams fits this picture. In the future, the hydrogen required to raise the product H/C ratio will be increasingly produced via gasification of large amounts of heavy residues. In the light of the strong preference towards using liquid fuels in the transport sector, the Shell Middle Distillate Synthesis process to convert natural gas into diesel of very high quality is discussed. Finally, a few comments on the use of hydrogen without a carbon carrier are made. Long lead times and the likelihood of producing the 'first' hydrogen from fossil fuel are highlighted. 13 figs., 6 tabs., 5 refs

  1. Multiple direct exchange in a Yang-Mills theory at high energy

    McCoy, B.M.; Wu, T.T.

    1976-01-01

    For eighth and higher orders, we obtain the leading high-energy behavior of the sum of all one-layer Feynman diagrams in Yang-Mills theory. These are the contributions from Feynman diagrams where the two incident fast particles exchange directly Yang-Mills bosons that are much less energetic. The incident particles may be either bosons or fermions of arbitrary isospin, and the result is also generalized to include the case of the Higgs scalar. The scattering amplitudes in all these cases are closely related, and all behave as s ln/sub n/ -1 s in the 2n + 2 order. Furthermore, in this leading order for n > or = 2, the exchanged isospins are always 0 and 2, no matter how high the isospins of the incident particles are

  2. Mechanism of multiple grating formation in high-energy recording of holographic sensors

    Yetisen, Ali K., E-mail: ay283@cam.ac.uk; Yun, Seok Hyun [Harvard Medical School and Wellman Center for Photomedicine, Massachusetts General Hospital, Boston, Massachusetts 02114 (United States); Montelongo, Yunuen [Electrical Engineering Division, Department of Engineering, University of Cambridge, Cambridge CB3 0FA (United Kingdom); Farandos, Nicholas M. [Department of Chemical Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ (United Kingdom); Naydenova, Izabela [Centre for Industrial and Engineering Optics, School of Physics, College of Sciences and Health, Dublin Institute of Technology, Dublin 8 (Ireland); Lowe, Christopher R. [Department of Chemical Engineering and Biotechnology, University of Cambridge, Tennis Court Road, Cambridge CB2 1QT (United Kingdom)

    2014-12-29

    We report numerical analyses of Bragg diffraction by Denisyuk reflection holograms recorded by a high-energy pulsed laser. An intensity threshold must be passed to pattern a multilayer reflection and transmission hologram, which exhibits a nonlinear fringe structure. Numerical evaluations are provided for the laser light intensity, readout diffraction offset angle, transmission of the layer, and thickness of the polymer matrix during hologram recording. A non-sinusoidal surface pattern is formed at the top of the multilayer structure, and its effect on the diffraction properties of the structure becomes significant when the recording tilt angle is increased. Experimental results show that the angle of the diffracted light increases nonlinearly according to the tilt geometry in grating formation.

  3. Multiple energy computed tomography with monochromatic x rays from the NSLS

    Dilmanian, F.A.; Nachaliel, E.; Garrett, R.F.; Thomlinson, W.C.; Chapman, L.D.; Moulin, H.R.; Oversluizen, T.; Rarback, H.M.; Rivers, M.; Spanne, P.; Thompson, A.C.; Zeman, H.D.

    1991-01-01

    We used monochromatic x rays from the X17 superconducting wiggler beamline at the National Synchrotron Light Source (NSLS), Brookhaven National Laboratory, for dual-energy quantitative computed tomography (CT) of a 27 mm-diameter phantom containing solutions of different KOH concentrations in cylindrical holes of 5-mm diameter. The CT configuration was a fixed horizontal fan-shaped beam of 1.5 mm height and 30 mm width, and a subject rotating around a vertical axis. The transmitted x rays were detected by a linear-array Si(Li) detector with 120 elements of 0.25 mm width each. We used a two-crystal Bragg-Bragg fixed-exit monochromator with Si crystals. Dual photon absorptiometry (DPA) CT data were taken at 20 and 38 keV. The reconstructed phantom images show the potential of the system for quantitative CT

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

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

    2014-09-01

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

  5. Measurement of bone mineral using multiple-energy x-ray absorptiometry

    Swanpalmer, Janos; Kullenberg, Ragnar; Hansson, Tommy

    1998-01-01

    Our laboratory has previously reported a method of determining the amount of bone mineral using triple-energy absorptiometry with a continuous x-ray spectrum. In the present study, the experimental properties of the technique were examined. The accuracy, the influence of fat content and body thickness and the in vitro and in vivo precision were analysed. The results found in this investigation showed that despite the complexity of the technique, the amount of bone mineral can be accurately determined. The in vivo precision was determined to be 3.4%, expressed as the coefficient of variation (CV), for different skeletal parts. The in vitro precision was found to be 2.1% (CV). Neither the fat content nor the body thickness had any effect on the measured bone mineral values. Excellent linearity and a close correlation were found between the true and the measured bone mineral values. (author)

  6. Multiple-energy tissue-cancellation applications of a digital beam attenuator to chest radiography

    Dobbins, J.T. III.

    1985-01-01

    The digitally-formed primary beam attenuator (DBA) spatially modulates the x-ray fluence incident upon the patient to selectively attenuate regions of interest. The DBA attenuating mask is constructed from CeO 2 powder by a modified printing technique and uses image information from an initial low-dose exposure. Two tissue-cancellation imaging techniques are investigated with the DBA: (1) energy-dependent information is used to form a beam attenuator that attenuates specific tissues in the primary x-ray beam for tissue-cancelled film radiography; (2) the beam attenuator is used to improve image signal-to-noise and scattered radiation properties in traditional energy-subtraction tissue-cancellation imaging with digital detectors. The tissue-cancellation techniques in the primary x-ray beam were capable of adequately removing either soft-tissue or bone from the final compensated film radiograph when using a phantom with well defined soft-tissue and bone sections. However, when tried on an anthropomorphic chest phantom the results were adequate for cancellation of large soft tissue structures, but unsatisfactory for cancellation of bony structures such as the ribs, because of the limited spatial frequency content of the attenuating mask. The second technique (with digital detectors) showed improved uniformity of image signal-to-noise and a two-fold increase in soft-tissue nodule contrast due to improved scattered radiation properties. The tissue-cancelled images contained residual image contributions from the presence of the attenuating mask, but this residual may be correctable by future algorithms

  7. Probing ultrafast carrier dynamics, nonlinear absorption

    We investigate the relaxation dynamics of photogenerated carriers in silicon nanowires consisting of a crystalline core and a surrounding amorphous shell, using femtosecond time resolved differential reflectivity and transmission spectroscopy at 3.15 eV and 1.57 eV photon energies. The complex behaviour of the ...

  8. A Low-Energy-Gap Thienochrysenocarbazole Dye for Highly Efficient Mesoscopic Titania Solar Cells: Understanding the Excited State and Charge Carrier Dynamics.

    Wang, Junting; Xie, Xinrui; Weng, Guorong; Yuan, Yi; Zhang, Jing; Wang, Peng

    2018-05-09

    Maintaining both a high external quantum efficiency and a large open-circuit photovoltage of dye-sensitized solar cells (DSSCs) is a crucial challenge in the process of developing narrow-energy-gap dyes for the capture of infrared solar photons. Herein, we report two donor-acceptor organic dyes, C294 and C295, with a polycyclic heteroaromatic unit, 6,11-dihydrothieno[3',2':8,9]chryseno[10,11,12,1-bcdefg]carbazole (TCC), as the central module of the electron donor, and ethylbenzothiadiazole-benzioc acid as the electron acceptor. The interfacial charge recombination was successfully mitigated by introducing an additional branched aliphatic chain in C295. Furthermore, the O⋅⋅⋅S nonbonding interaction between the oxygen atom of the alkoxy group and the sulfur atom of the thiophene in C295 controlled the conformation of C295, resulting in a narrow energy-gap. Time-resolved spectroscopic measurements on C294 and the model dye C272 indicated that the elevation of the HOMO energy level decreased the kinetics and yield of hole injection owing to a reduction in the driving force and that the shortened excited-state lifetime caused by the narrowing of the energy gap was unfavorable for electron injection. By fine tuning the composition of the electrolyte, C294 and C295 eventually achieved high power conversion efficiencies of 11.5 % and 12.4 %, respectively, under full sunlight of air mass 1.5 global conditions. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Asymmetric Carrier Random PWM

    Mathe, Laszlo; Lungeanu, Florin; Rasmussen, Peter Omand

    2010-01-01

    index. The flat motor current spectrum generates an acoustical noise close to the white noise, which may improve the acoustical performance of the drive. The new carrier wave is easy to implement digitally, without employing any external circuits. The modulation method can be used in open, as well...

  10. Willis H Carrier

    Home; Journals; Resonance – Journal of Science Education; Volume 17; Issue 2. Willis H. Carrier - Father of Air Conditioning. R V Simha. General Article Volume 17 Issue 2 February 2012 pp 117-138. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/017/02/0117-0138 ...

  11. Modeling the energy content of combustible ship-scrapping waste at Alang-Sosiya, India, using multiple regression analysis.

    Reddy, M Srinivasa; Basha, Shaik; Joshi, H V; Sravan Kumar, V G; Jha, B; Ghosh, P K

    2005-01-01

    Alang-Sosiya is the largest ship-scrapping yard in the world, established in 1982. Every year an average of 171 ships having a mean weight of 2.10 x 10(6)(+/-7.82 x 10(5)) of light dead weight tonnage (LDT) being scrapped. Apart from scrapped metals, this yard generates a massive amount of combustible solid waste in the form of waste wood, plastic, insulation material, paper, glass wool, thermocol pieces (polyurethane foam material), sponge, oiled rope, cotton waste, rubber, etc. In this study multiple regression analysis was used to develop predictive models for energy content of combustible ship-scrapping solid wastes. The scope of work comprised qualitative and quantitative estimation of solid waste samples and performing a sequential selection procedure for isolating variables. Three regression models were developed to correlate the energy content (net calorific values (LHV)) with variables derived from material composition, proximate and ultimate analyses. The performance of these models for this particular waste complies well with the equations developed by other researchers (Dulong, Steuer, Scheurer-Kestner and Bento's) for estimating energy content of municipal solid waste.

  12. Multiple regimes of operation in bimodal AFM: understanding the energy of cantilever eigenmodes

    Daniel Kiracofe

    2013-06-01

    Full Text Available One of the key goals in atomic force microscopy (AFM imaging is to enhance material property contrast with high resolution. Bimodal AFM, where two eigenmodes are simultaneously excited, confers significant advantages over conventional single-frequency tapping mode AFM due to its ability to provide contrast between regions with different material properties under gentle imaging conditions. Bimodal AFM traditionally uses the first two eigenmodes of the AFM cantilever. In this work, the authors explore the use of higher eigenmodes in bimodal AFM (e.g., exciting the first and fourth eigenmodes. It is found that such operation leads to interesting contrast reversals compared to traditional bimodal AFM. A series of experiments and numerical simulations shows that the primary cause of the contrast reversals is not the choice of eigenmode itself (e.g., second versus fourth, but rather the relative kinetic energy between the higher eigenmode and the first eigenmode. This leads to the identification of three distinct imaging regimes in bimodal AFM. This result, which is applicable even to traditional bimodal AFM, should allow researchers to choose cantilever and operating parameters in a more rational manner in order to optimize resolution and contrast during nanoscale imaging of materials.

  13. A Small Modular Reactor Design for Multiple Energy Applications: HTR50S

    Yan, X.; Tachibana, Y.; Ohashi, H.; Sato, H.; Tazawa, Y.; Kunitomi, K. [Japan Atomic Energy Agency, Ibaraki (Japan)

    2013-06-15

    HTR50S is a small modular reactor system based on HTGR. It is designed for a triad of applications to be implemented in successive stages. In the first stage, a base plant for heat and power is constructed of the fuel proven in JAEA's 950 .deg. C, 30MWt test reactor HTTR and a conventional steam turbine to minimize development risk. While the outlet temperature is lowered to 750 .deg. C for the steam turbine, thermal power is raised to 50MWt by enabling 40% greater power density in 20% taller core than the HTTR. However the fuel temperature limit and reactor pressure vessel diameter are kept. In second stage, a new fuel that is currently under development at JAEA will allow the core outlet temperature to be raised to 900 .deg. C for the purpose of demonstrating more efficient gas turbine power generation and high temperature heat supply. The third stage adds a demonstration of nuclear-heated hydrogen production by a thermochemical process. A licensing approach to coupling high temperature industrial process to nuclear reactor will be developed. The low initial risk and the high longer-term potential for performance expansion attract development of the HTR50S as a multipurpose industrial or distributed energy source.

  14. Environment, economy and energy: Meeting the multiple challenges of the 1990s

    Rowe, J.W.; LaFleur, C.A.

    1992-01-01

    In the fall of 1991, New England Electric System (NEES) released its third major resource plan, 'NEESPLAN 3: Environment, Economy, and Energy in the 1990s.' In it, the Company set three major goals for the decade: (1) to reduce continuously the environmental impacts of providing electric service, including a 45% reduction in our weighted air emissions index between 1990 and 2000; (2) to maintain competitiveness by keeping price increases at or below inflation, on average, through the year 2000; and, (3) to ensure resource diversity and reliability by increasing nonutility generation, repowering existing power plants, and exploring new technologies. NEES developed these goals to provide a unified central vision for the company to respond to changing times. NEES is basing their corporate direction on their fundamental beliefs that environmental concerns are here to stay, and that these concerns must be met in tandem with cost and service challenges. By implementing NESSPLAN 3, NEES wants to demonstrate that many of the public policy goals of the environmental and regulatory communities can be better achieved by focusing on overall results rather than by litigating the details of individual power supply decisions. This article discusses the development of NEESPLAN 3, while paying particular attention to the various alternatives they examined to reach the goal of a 45% reduction in air emissions

  15. Energy dependence of the neutron multiplicity P/sub nu/ in fast neutron induced fission of /sup 235,238/U and 239Pu

    Zucker, M.S.; Holden, N.E.

    1986-01-01

    Certain applications require knowledge of the higher moments of the neutron multiplicity probability. It can be shown that the second factorial moment is proportional to the fission rate in the sample, and that the third factorial moment can be of use in disentangling spontaneous fission from induced fission. Using a source of unpublished work in which neutron multiplicities were derived for the fast neutron induced fission of U-235, U-238, and Pu-239, the multiplicity probability has been calculated as a function of neutron energy for the energy range 0 to 10 MeV

  16. Sealed substrate carrier for electroplating

    Ganti, Kalyana Bhargava [Fremont, CA

    2012-07-17

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

  17. Rational energy utilization and utilization of solar energy in the open-air swimming pool and in the multiple purpose hall at Wiehl. Final report. Pt. G

    Bouillon, H; Jensch, K; Jensch, W; Biasin, K; Dreisbach, K; Fruehauf, H J

    1982-12-01

    The research- and demonstration project in Wiehl consists mainly of an open-air swimming pool heated by solar energy and of a multiple purpose hall which is chiefly used as an ice-sport hall. The ice-field is cooled by means of a refrigeration system. The waste heat developing during freezing is used for water heating, space heating and hall-air heating for the multiple purpose hall and for after-heating of the pool water in the open-air swimming pool. In artificial ice-fields operated without interruptions during quite a long time, the subsoil may freeze. In this case there is the risk of the field constructions being damaged by the tensile forces of the frozen subsoil. In order to avoid this heating coils are installed below the fields in many cases today, due to which part of the waste heat developing during ice-production can be used to heat the field subsoil and thus avoid the risk of destruction.

  18. Temperature-dependent field-effect carrier mobility in organic thin-film transistors with a gate SiO2 dielectric modified by H2O2 treatment

    Lin, Yow-Jon; Hung, Cheng-Chun

    2018-02-01

    The effect of the modification of a gate SiO2 dielectric using an H2O2 solution on the temperature-dependent behavior of carrier transport for pentacene-based organic thin-film transistors (OTFTs) is studied. H2O2 treatment leads to the formation of Si(-OH) x (i.e., the formation of a hydroxylated layer) on the SiO2 surface that serves to reduce the SiO2 capacitance and weaken the pentacene-SiO2 interaction, thus increasing the field-effect carrier mobility ( µ) in OTFTs. The temperature-dependent behavior of carrier transport is dominated by the multiple trapping model. Note that H2O2 treatment leads to a reduction in the activation energy. The increased value of µ is also attributed to the weakening of the interactions of the charge carriers with the SiO2 dielectric that serves to reduce the activation energy.

  19. Slow hot carrier cooling in cesium lead iodide perovskites

    Shen, Qing; Ripolles, Teresa S.; Even, Jacky; Ogomi, Yuhei; Nishinaka, Koji; Izuishi, Takuya; Nakazawa, Naoki; Zhang, Yaohong; Ding, Chao; Liu, Feng; Toyoda, Taro; Yoshino, Kenji; Minemoto, Takashi; Katayama, Kenji; Hayase, Shuzi

    2017-10-01

    Lead halide perovskites are attracting a great deal of interest for optoelectronic applications such as solar cells, LEDs, and lasers because of their unique properties. In solar cells, heat dissipation by hot carriers results in a major energy loss channel responsible for the Shockley-Queisser efficiency limit. Hot carrier solar cells offer the possibility to overcome this limit and achieve energy conversion efficiency as high as 66% by extracting hot carriers. Therefore, fundamental studies on hot carrier relaxation dynamics in lead halide perovskites are important. Here, we elucidated the hot carrier cooling dynamics in all-inorganic cesium lead iodide (CsPbI3) perovskite using transient absorption spectroscopy. We observe that the hot carrier cooling rate in CsPbI3 decreases as the fluence of the pump light increases and the cooling is as slow as a few 10 ps when the photoexcited carrier density is 7 × 1018 cm-3, which is attributed to phonon bottleneck for high photoexcited carrier densities. Our findings suggest that CsPbI3 has a potential for hot carrier solar cell applications.

  20. Multiple Electron Charge Transfer Chemistries for Electrochemical Energy Storage Systems: The Metal Boride and Metal Air Battery

    Stuart, Jessica F.

    The primary focus of this work has been to develop high-energy capacity batteries capable of undergoing multiple electron charge transfer redox reactions to address the growing demand for improved electrical energy storage systems that can be applied to a range of applications. As the levels of carbon dioxide (CO2) increase in the Earth's atmosphere, the effects on climate change become increasingly apparent. According to the Energy Information Administration (EIA), the U.S. electric power sector is responsible for the release of 2,039 million metric tons of CO2 annually, equating to 39% of total U.S. energy-related CO2 emissions. Both nationally and abroad, there are numerous issues associated with the generation and use of electricity aside from the overwhelming dependence on fossil fuels and the subsequent carbon emissions, including reliability of the grid and the utilization of renewable energies. Renewable energy makes up a relatively small portion of total energy contributions worldwide, accounting for only 13% of the 3,955 billion kilowatt-hours of electricity produced each year, as reported by the EIA. As the demand to reduce our dependence on fossils fuels and transition to renewable energy sources increases, cost effective large-scale electrical energy storage must be established for renewable energy to become a sustainable option for the future. A high capacity energy storage system capable of leveling the intermittent nature of energy sources such as solar, wind, and water into the electric grid and provide electricity at times of high demand will facilitate this transition. In 2008, the Licht Group presented the highest volumetric energy capacity battery, the vanadium diboride (VB2) air battery, exceedingly proficient in transferring eleven electrons per molecule. This body of work focuses on new developments to this early battery such as fundamentally understanding the net discharge mechanism of the system, evaluation of the properties and

  1. Charge carrier dynamics in thin film solar cells

    Strothkaemper, Christian

    2013-06-24

    This work investigates the charge carrier dynamics in three different technological approaches within the class of thin film solar cells: radial heterojunctions, the dye solar cell, and microcrystalline CuInSe{sub 2}, focusing on charge transport and separation at the electrode, and the relaxation of photogenerated charge carriers due to recombination and energy dissipation to the phonon system. This work relies mostly on optical-pump terahertz-probe (OPTP) spectroscopy, followed by transient absorption (TA) and two-photon photoemission (2PPE). The charge separation in ZnO-electrode/In{sub 2}S{sub 3}-absorber core/shell nanorods, which represent a model system of a radial heterojunction, is analyzed by OPTP. It is concluded, that the dynamics in the absorber are determined by multiple trapping, which leads to a dispersive charge transport to the electrode that lasts over hundreds of picoseconds. The high trap density on the order of 10{sup 19}/cm{sup 3} is detrimental for the injection yield, which exhibits a decrease with increasing shell thickness. The heterogeneous electron transfer from a series of model dyes into ZnO proceeds on a time-scale of 200 fs. However, the photoconductivity builds up just on a 2-10 ps timescale, and 2PPE reveals that injected electrons are meanwhile localized spatially and energetically at the interface. It is concluded that the injection proceeds through adsorbate induced interface states. This is an important result because the back reaction from long lived interface states can be expected to be much faster than from bulk states. While the charge transport in stoichiometric CuInSe{sub 2} thin films is indicative of free charge carriers, CuInSe{sub 2} with a solar cell grade composition (Cu-poor) exhibits signs of carrier localization. This detrimental effect is attributed to a high density of charged defects and a high degree of compensation, which together create a spatially fluctuating potential that inhibits charge transport. On

  2. Time Resolved Studies of Carrier Dynamics in III -v Heterojunction Semiconductors.

    Westland, Duncan James

    Available from UMI in association with The British Library. Requires signed TDF. Picosecond time-resolution photoluminescence spectroscopy has been used to study transient processes in Ga _{.47}In_{.53 }As/InP multiple quantum wells (MQWs), and in bulk Ga_{.47}In _{.53}As and GaSb. To facilitate the experimental studies, apparatus was constructed to allow the detection of transient luminescence with 3ps time resolution. A frequency upconversion technique was employed. Relaxation of energetic carriers in bulk Ga _{.47}In_{.53 }As by optic phonons has been investigated, and, at carrier densities ~3 times 10^{18}cm ^{-3} is found to be a considerably slower process than simple theory predicts. The discrepancy is resolved by the inclusion of a non-equilibrium population of longitudinal optic phonons in the theoretical description. Slow energy loss is also observed in a 154A MQW under similar conditions, but carriers are found to relax more quickly in a 14A MQW with a comparable repeat period. The theory of non-equilibrium mode occupation is modified to describe the case of a MQW and is found to agree with experiment. Carrier relaxation in GaSb is studied and the importance of occupation of the L _6 conduction band valley in this material is demonstrated. The ambipolar diffusion of a photoexcited carrier plasma through an InP capping layer was investigated using an optical time-of-flight technique. This experiment also enables the efficiency of carrier capture by a Ga _{.47}In_{.53 }As quantum well to be determined. A capture time of 4ps was found.

  3. Carrier transport uphill. I. General

    Rosenberg, T; Wilbrandt, W

    1963-01-01

    A quantitative treatment of a carrier pump operating with two carrier forms C and Z is presented. Asymmetric metabolic reactions are assumed to transform Z into C on one and C into Z on the other side of the membrane, establishing a carrier cycle. The kinetical consequences of this mechanism...

  4. Bio-SNG. Prospective renewable energy carrier in the E.ON gas grid; Bio-SNG. Zukuenftiger regenerativer Energietraeger im E.ON Gasnetz

    Adelt, Marius; Vogel, Alexander [E.ON Ruhrgas AG, Essen (Germany)

    2010-10-15

    Biogas processing and injection into the natural gas pipeline system on an industrial scale has been around in Germany for some time. E.ON operates a number of biogas plants with a production capacity of 200-1700 m{sup 3}/h. More plants are under construction or planned. The German government is looking to increase the share of biogas (upgraded to natural gas quality) in the pipeline system to 6 billion m{sup 3}/a by 2020, so significantly more production capacity is needed. Biogas is produced mainly from dedicated energy crops (maize) as well as several catch crops and, depending on the processing plant, various amounts of bio residues. The biogas is upgraded to natural gas quality and fed into the pipeline system as biomethane (E.ON: bio natural gas). To achieve the ambitious production targets it will be necessary to tap the unused potential of wood for gasification and subsequent methanisation into bio-SNG. E.ON AG actively promotes the development and introduction of this technology. This article provides an overview of different aspects of bio-SNG production and use including: Utilisation paths for biomethane/bio-SNG (heat, fuel, CHP), Potential of wood for bio-SNG production, Bio-SNG production technologies, Current E.ON activities and projects. (orig.)

  5. Carrier dynamics of InxGa1-xN/GaN multiple quantum wells grown on (−201) β-Ga2O3 for bright vertical light emitting diodes

    Mumthaz Muhammed, Mufasila; Xu, Jian; Wehbe, Nimer; Roqan, Iman S.

    2018-01-01

    High-quality InxGa1-xN/GaN multi-quantum well (MQW) structures (0.05≤x≤0.13), are successfully grown on transparent and conductive (−201)-oriented β-Ga2O3 substrate. Scanning-transmission electron microscopy and secondary ion mass spectrometry (SIMS) show well-defined high quality MQWs, while the In and Ga compositions in the wells and the barriers are estimated by SIMS. Temperature-dependant Photoluminescence (PL) confirms high optical quality with a strong bandedge emission and negligble yellow band. time-resolved PL measurements (via above/below-GaN bandgap excitations) explain carrier dynamics, showing that the radiative recombination is predominant. Our results demonstrate that (−201)-oriented β-Ga2O3 is a strong candidate as a substrate for III-nitride-based vertical- emitting devices.

  6. Carrier dynamics of InxGa1-xN/GaN multiple quantum wells grown on (−201) β-Ga2O3 for bright vertical light emitting diodes

    Mumthaz Muhammed, Mufasila

    2018-05-30

    High-quality InxGa1-xN/GaN multi-quantum well (MQW) structures (0.05≤x≤0.13), are successfully grown on transparent and conductive (−201)-oriented β-Ga2O3 substrate. Scanning-transmission electron microscopy and secondary ion mass spectrometry (SIMS) show well-defined high quality MQWs, while the In and Ga compositions in the wells and the barriers are estimated by SIMS. Temperature-dependant Photoluminescence (PL) confirms high optical quality with a strong bandedge emission and negligble yellow band. time-resolved PL measurements (via above/below-GaN bandgap excitations) explain carrier dynamics, showing that the radiative recombination is predominant. Our results demonstrate that (−201)-oriented β-Ga2O3 is a strong candidate as a substrate for III-nitride-based vertical- emitting devices.

  7. Dedicated Carrier Deployment in Heterogeneous Networks with Inter-site Carrier Aggregation

    Wang, Hua; Rosa, Claudio; Pedersen, Klaus I.

    2013-01-01

    the macrocell or the picocell using simple cell range expansion (RE). Extensive system-level simulations have been conducted to investigate the performance gains that can be achieved with inter-site CA under different traffic models and user distributions. Results show that using inter-site CA between......) or picos with dedicated carrier deployment. Collaborative inter-site carrier aggregation (CA) is proposed in scenarios with macro+RRH deployment to make an efficient use of the fragmented spectrum from multiple cells. While in scenarios with macro+pico deployment, UEs can only connect to either...

  8. Maintainable substrate carrier for electroplating

    Chen, Chen-An [Milpitas, CA; Abas, Emmanuel Chua [Laguna, PH; Divino, Edmundo Anida [Cavite, PH; Ermita, Jake Randal G [Laguna, PH; Capulong, Jose Francisco S [Laguna, PH; Castillo, Arnold Villamor [Batangas, PH; Ma,; Xiaobing, Diana [Saratoga, CA

    2012-07-17

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

  9. Potential of HfN, ZrN, and TiH as hot carrier absorber and Al2O3/Ge quantum well/Al2O3 and Al2O3/PbS quantum dots/Al2O3 as energy selective contacts

    Shrestha, Santosh; Chung, Simon; Liao, Yuanxun; Wang, Pei; Cao, Wenkai; Wen, Xiaoming; Gupta, Neeti; Conibeer, Gavin

    2017-08-01

    The hot carrier (HC) solar cell is one of the most promising advanced photovoltaic concepts. It aims to minimise two major losses in single junction solar cells due to sub-band gap loss and thermalisation of above band gap photons by using a small bandgap absorber, and, importantly, collecting the photo-generated carriers before they thermalise. In this paper we will present recent development of the two critical components of the HC solar cell, i.e., the absorber and energy selective contacts (ESCs). For absorber, fabrication and carrier cooling rates in potential bulk materials — hafnium nitride, zirconium nitride, and titanium hydride are presented. Results of ESCs employing double barrier resonant tunneling structures Al2O3/Ge quantum well (QW)/Al2O3 and Al2O3/PbS quantum dots (QDs)/Al2O3 are also presented. These results are expected to guide further development of practical HC solar cell devices.

  10. Screening in crystalline liquids protects energetic carriers in hybrid perovskites

    Zhu, Haiming; Miyata, Kiyoshi; Fu, Yongping; Wang, Jue; Joshi, Prakriti; Niesner, Daniel; Williams, Kristopher; Jin, Song; Zhu, Xiaoyang

    Hybrid lead halide perovskites exhibit carrier properties that resemble those of pristine nonpolar semiconductors despite static and dynamic disorder, but how carriers are protected from efficient scattering with charged defects and optical phonons is unknown. Here, we reveal the carrier protection mechanism by comparing three single-crystal lead bromide perovskites: CH3NH3PbBr3, CH(NH2)2PbBr3, and CsPbBr3. We observed hot fluorescence emission from energetic carriers with 102 picosecond lifetimes in CH3NH3PbBr3 or CH(NH,SUB>2)2PbBr3, but not in CsPbBr3. The hot fluorescence is correlated with liquid-like molecular reorientational motions, suggesting that dynamic screening protects energetic carriers via solvation or large polaron formation on time scales competitive with that of ultrafast cooling. Similar protections likely exist for band-edge carriers. The long-lived energetic carriers may enable hot-carrier solar cells with efficiencies exceeding the Shockley-Queisser limit. This work was supported by U.S. Department of Energy Grant ER46980, National Science Foundation, Grant DMR 1420634 (MRSEC), and Department of Energy Award DE-FG02-09ER46664.

  11. Autonomous component carrier selection

    Garcia, Luis Guilherme Uzeda; Pedersen, Klaus; Mogensen, Preben

    2009-01-01

    management and efficient system operation. Due to the expected large number of user-deployed cells, centralized network planning becomes unpractical and new scalable alternatives must be sought. In this article, we propose a fully distributed and scalable solution to the interference management problem...... in local areas, basing our study case on LTE-Advanced. We present extensive network simulation results to demonstrate that a simple and robust interference management scheme, called autonomous component carrier selection allows each cell to select the most attractive frequency configuration; improving...... the experience of all users and not just the few best ones; while overall cell capacity is not compromised....

  12. Serum Compounds of Energy Metabolism Impairment Are Related to Disability, Disease Course and Neuroimaging in Multiple Sclerosis.

    Lazzarino, Giacomo; Amorini, Angela M; Petzold, Axel; Gasperini, Claudio; Ruggieri, Serena; Quartuccio, Maria Esmeralda; Lazzarino, Giuseppe; Di Stasio, Enrico; Tavazzi, Barbara

    2017-11-01

    Multiple sclerosis (MS) is characterized by primary inflammation, demyelination, and progressive neurodegeneration. A biochemical MS feature is neuronal mitochondrial dysfunction, compensated by anaerobic metabolism increase, likely aggravating progression of neurodegeneration. Here, we characterized a pragmatic serum profile of compounds related to mitochondrial energy metabolism of potential clinical use. Blood samples of 518 well characterized (disability, disease course) MS patients and 167 healthy controls were analyzed for serum purines, pyrimidines, creatinine, and lactate. Nine of the 15 compounds assayed, hypoxanthine, xanthine, uric acid, inosine, uracil, β-pseudouridine, uridine, creatinine, and lactate, differed significantly between MS patients and controls (p < 0.0001). Using these nine compounds, a unifying Biomarker Score was calculated. Controls and MS patients had mean Biomarker Scores of 0.4 ± 0.7 and 4.4 ± 1.9, respectively (p < 0.00001). The Biomarker Score was higher in patients with progressive (6.0 ± 1.8 than with relapsing remitting disease course (3.6 ± 1.5, p < 0.00001). High association between the Biomarker Score and increase in disability (EDSS) was also observed. Additionally, in 50 patients who underwent magnetic resonance imaging (MRI), increase in the Biomarker Score correlated to neuroanatomical alterations. These results, obtained in a large cohort of MS patients evaluated for serum metabolic compounds connected to energy metabolism, demonstrated that the Biomarker Score might represent a pragmatic, resource saving, easy to obtain, laboratory tool useful to monitor MS patients and predict at an early stage who will switch from an RR to a progressive disease course. For the first time, it was also clearly shown a link between mitochondrial dysfunction and MRI lesions characteristic of MS.

  13. K$^{-}$ over K$^{+}$ multiplicity ratio for kaons produced in DIS with a large fraction of the virtual-photon energy

    Akhunzyanov, R.; The COMPASS collaboration; Alexeev, G.D.; Amoroso, A.; Andrieux, V.; Anfimov, N.V.; Anosov, V.; Antoshkin, A.; Augsten, K.; Augustyniak, W.; Austregesilo, A.; Azevedo, C.D.R.; Badełek, B.; Balestra, F.; Ball, M.; Barth, J.; Beck, R.; Bedfer, Y.; Bernhard, J.; Bicker, K.; Bielert, E.R.; Birsa, R.; Bodlak, M.; Bordalo, P.; Bradamante, F.; Bressan, A.; Büchele, M.; Burtsev, V.E.; Capozza, L.; Chang, W.-C.; Chatterjee, C.; Chiosso, M.; Chumakov, A.G.; Chung, S.-U.; Cicuttin, A.; Crespo, M.L.; Curiel, Q.; Dalla Torre, S.; Dasgupta, S.S.; Dasgupta, S.; Denisov, O.Yu.; Dhara, L.; Donskov, S.V.; Doshita, N.; Dreisbach, Ch.; Dünnweber, W.; Dusaev, R.R.; Dziewiecki, M.; Efremov, A.; Eversheim, P.D.; Faessler, M.; Ferrero, A.; Finger, M.; jr., M.Finger; Fischer, H.; Franco, C.; du Fresne von Hohenesche, N.; Friedrich, J.M.; Frolov, V.; Gautheron, F.; Gavrichtchouk, O.P.; Gerassimov, S.; Giarra, J.; Gnesi, I.; Gorzellik, M.; Grasso, A.; Gridin, A.; Grosse Perdekamp, M.; Grube, B.; Guskov, A.; Hahne, D.; Hamar, G.; von Harrach, D.; Heitz, R.; Herrmann, F.; Horikawa, N.; d'Hose, N.; Hsieh, C.-Y.; Huber, S.; Ishimoto, S.; Ivanov, A.; Ivanshin, Yu.; Iwata, T.; Jary, V.; Joosten, R.; Jörg, P.; Kabuß, E.; Kerbizi, A.; Ketzer, B.; Khaustov, G.V.; Khokhlov, Yu.A.; Kisselev, Yu.; Klein, F.; Koivuniemi, J.H.; Kolosov, V.N.; Kondo, K.; Konorov, I.; Konstantinov, V.F.; Kotzinian, A.M.; Kouznetsov, O.M.; Kral, Z.; Krämer, M.; Krinner, F.; Kroumchtein, Z.V.; Kulinich, Y.; Kunne, F.; Kurek, K.; Kurjata, R.P.; Kuznetsov, I.I.; Kveton, A.; Lednev, A.A.; Levchenko, E.A.; Levorato, S.; Lian, Y.-S.; Lichtenstadt, J.; Longo, R.; Lyubovitskij, V.E.; Maggiora, A.; Magnon, A.; Makins, N.; Makke, N.; Mallot, G.K.; Mamon, S.A.; Marchand, C.; Marianski, B.; Martin, A.; Marzec, J.; Matoušek, J.; Matsuda, H.; Matsuda, T.; Meshcheryakov, G.V.; Meyer, M.; Meyer, W.; Mikhailov, Yu.V.; Mikhasenko, M.; Mitrofanov, E.; Mitrofanov, N.; Miyachi, Y.; Moretti, A.; Nagaytsev, A.; Nerling, F.; Neyret, D.; Nový, J.; Nowak, W.-D.; Nukazuka, G.; Nunes, A.S.; Olshevsky, A.G.; Orlov, I.; Ostrick, M.; Panzieri, D.; Parsamyan, B.; Paul, S.; Peng, J.-C.; Pereira, F.; Pesaro, G.; Pešek, M.; Pešková, M.; Peshekhonov, D.V.; Pierre, N.; Platchkov, S.; Pochodzalla, J.; Polyakov, V.A.; Pretz, J.; Quaresma, M.; Quintans, C.; Ramos, S.; Regali, C.; Reicherz, G.; Riedl, C.; Ryabchikov, D.I.; Rybnikov, A.; Rychter, A.; Salac, R.; Samoylenko, V.D.; Sandacz, A.; Sarkar, S.; Savin, I.A.; Sawada, T.; Sbrizzai, G.; Schiavon, P.; Schmieden, H.; Seder, E.; Selyunin, A.; Silva, L.; Sinha, L.; Sirtl, S.; Slunecka, M.; Sozzi, F.; Smolik, J.; Srnka, A.; Steffen, D.; Stolarski, M.; Subrt, O.; Sulc, M.; Suzuki, H.; Szabelski, A.; Szameitat, T.; Sznajder, P.; Tasevsky, M.; Tessaro, S.; Tessarotto, F.; Thiel, A.; Tomsa, J.; Tosello, F.; Tskhay, V.; Uhl, S.; Vasilishin, B.I.; Vauth, A.; Veit, B.M.; Veloso, J.; Vidon, A.; Virius, M.; Wallner, S.; Wilfert, M.; Windmolders, R.; Zaremba, K.; Zavada, P.; Zavertyaev, M.; Zemlyanichkina, E.; Zhuravlev, N.; Ziembicki, M.

    2018-01-01

    The K$^{-}$ over K$^{+}$ multiplicity ratio is measured in deep-inelastic scattering, for the first time for kaons carrying a large fraction $z$ of the virtual-photon energy. The data were obtained by the COMPASS collaboration using a 160 GeV muon beam and an isoscalar $^6$LiD target. The regime of deep-inelastic scattering is ensured by requiring $Q^2>1$ (GeV/$c)^2$ for the photon virtuality and $W>5$ GeV/$c^2$ for the invariant mass of the produced hadronic system. Kaons are identified in the momentum range from 12 GeV/$c$ to 40 GeV/$c$, thereby restricting the range in Bjorken-$x$ to $0.010.75$. For very large values of $z$, $i.e.$ $z>0.8$, the results contradict expectations obtained using the formalism of (next-to-)leading order perturbative quantum chromodynamics. This may imply that cross-section factorisation or/and universality of (kaon) fragmentation functions do not hold. Our studies suggest that within this formalism an additional correction may be required, which takes into account th...

  14. Nonequilibrium carrier dynamics in transition metal dichalcogenide semiconductors

    Steinhoff, A.; Florian, M.; Rösner, M.; Lorke, M.; Wehling, T. O.; Gies, C.; Jahnke, F.

    2016-09-01

    When exploring new materials for their potential in (opto)electronic device applications, it is important to understand the role of various carrier interaction and scattering processes. In atomically thin transition metal dichalcogenide semiconductors, the Coulomb interaction is known to be much stronger than in quantum wells of conventional semiconductors like GaAs, as witnessed by the 50 times larger exciton binding energy. The question arises, whether this directly translates into equivalently faster carrier-carrier Coulomb scattering of excited carriers. Here we show that a combination of ab initio band-structure and many-body theory predicts Coulomb-mediated carrier relaxation on a sub-100 fs time scale for a wide range of excitation densities, which is less than an order of magnitude faster than in quantum wells.

  15. Carrier-carrier scattering in the gain dynamics of InxGa1-xAs/AlyGa1-yAs diode lasers

    Sanders, Gary D; Sun, C.-K.; Golubovic, B.

    1996-01-01

    Ultrafast optical nonlinearities in semiconductors play a central role in determining transient amplification and pulse-dependent gain saturation in diode lasers. Both carrier-phonon and carrier-carrier scattering are expected to determine the gain dynamics in these systems. We present a relaxation......-Dirac function where the chemical potential and temperature are self-consistently chosen so that both particle number and energy are conserved in the carrier-carrier scattering process. The relaxation approximation makes the problem an effective one-dimensional problem which can then be solved directly...

  16. Hydrogen: an energy carrier of the future

    Hamerak, K

    1977-02-01

    Some advantages and fields of application of hydrogen are outlined in the introduction. Hydrogen production by conventional water electrolysis, by the thermochemical iron-chlorine cycle process, and by a new water electrolysis method still in the laboratory stage are dealt with in which the electrolysis voltage is considerably reduced by the action of solar UV light on an anode consisting of p-conducting material.

  17. Multiplicity and Pseudorapidity Distributions from $p\\bar{p}$ Collisions at Center-of-Mass Energy 1.8-TeV

    Allen, Charles Cameron [Purdue U.

    1991-12-01

    Charged-particle multiplicity and pseudorapidity distributions produced in protonantiproton collisions at center of mass energy 1.8 TeV and measured in the Central Tracking Chamber are discussed. The data were taken using a minimum bias trigger at E-735 at Fermi lab.

  18. LIQUIFIED NATURAL GAS (LNG CARRIERS

    Daniel Posavec

    2010-12-01

    Full Text Available Modern liquefied natural gas carriers are double-bottom ships classified according to the type of LNG tank. The tanks are specially designed to store natural gas cooled to -161°C, the boiling point of methane. Since LNG is highly flammable, special care must be taken when designing and operating the ship. The development of LNG carriers has begun in the middle of the twentieth century. LNG carrier storage space has gradually grown to the current maximum of 260000 m3. There are more than 300 LNG carriers currently in operation (the paper is published in Croatian.

  19. Mapping and modeling multiple benefits of energy efficiency and emission mitigation in China’s cement industry at the provincial level

    Zhang, Shaohui; Worrell, Ernst; Crijns-Graus, Wina

    2015-01-01

    Highlights: • Provincial disparities in energy use and emissions are quantified for China’s cement industry. • We describe emission mitigation impacts on EEMs with integrated assessment model. • We quantify the multiple benefits potential in China’s cement industry on provincial level. • Energy efficiency would lead to huge reductions in air pollution in all provinces. • We discuss uncertainty in relation to distribution of energy saving and emission reduction. - Abstract: China’s cement industry is the second largest energy consumer and key emitter of CO 2 and air pollutants. It accounts for 7% of total energy consumption in China and 15% of CO 2 , 21% of PM, 4% SO 2 and 10% of NOx of total emissions, respectively. Provincial disparities in energy consumption and emissions of CO 2 and air pollutants in China’s cement industry are rarely quantified. In this study, an integrated assessment model including provincial energy conservation supply curves (ECSC) (which can shows the cost-effective and technical energy saving potential per province), the Greenhouse Gas and Air Pollution Interactions and Synergies (GAINS) model (which can be used to calculate air pollutant emissions), and ArcGIS (a geographical information system (GIS) with elaborated spatial functions) is developed and used to assess the potential of energy savings in terms of emission mitigation of CO 2 and air pollutants and multiple benefits of energy efficiency measures at the provincial level during the period 2011–2030. The results show significant heterogeneity across provinces in terms of potential of energy saving as well as emission mitigation of CO 2 and air pollutants (i.e. PM, SO 2 , and NOx) in the next two decades. Seven provinces (i.e. Shandong, Sichuan, Jiangsu, Guangdong, Zhejiang, Henan, Hebei), six of which are located in the central- and east-China, account for 47% of the total energy saving potential, equivalent to 26% of baseline energy use in 2030. The energy

  20. The combination of energy-dependent internal adaptation mechanisms and external factors enables Listeria monocytogenes to express a strong starvation survival response during multiple-nutrient starvation.

    Lungu, Bwalya; Saldivar, Joshua C; Story, Robert; Ricke, Steven C; Johnson, Michael G

    2010-05-01

    The goal of this study was to characterize the starvation survival response (SSR) of a wild-type Listeria monocytogenes 10403S and an isogenic DeltasigB mutant strain during multiple-nutrient starvation conditions over 28 days. This study examined the effects of inhibitors of protein synthesis, the proton motive force, substrate level phosphorylation, and oxidative phosphorylation on the SSR of L. monocytogenes 10403S and a DeltasigB mutant during multiple-nutrient starvation. The effects of starvation buffer changes on viability were also examined. During multiple-nutrient starvation, both strains expressed a strong SSR, suggesting that L. monocytogenes possesses SigB-independent mechanism(s) for survival during multiple-nutrient starvation. Neither strain was able to express an SSR following starvation buffer changes, indicating that the nutrients/factors present in the starvation buffer could be a source of energy for cell maintenance and survival. Neither the wild-type nor the DeltasigB mutant strain was able to elicit an SSR when exposed to the protein synthesis inhibitor chloramphenicol within the first 4 h of starvation. However, both strains expressed an SSR when exposed to chloramphenicol after 6 h or more of starvation, suggesting that the majority of proteins required to elicit an effective SSR in L. monocytogenes are likely produced somewhere between 4 and 6 h of starvation. The varying SSRs of both strains to the different metabolic inhibitors under aerobic or anaerobic conditions suggested that (1) energy derived from the proton motive force is important for an effective SSR, (2) L. monocytogenes utilizes an anaerobic electron transport during multiple-nutrient starvation conditions, and (3) the glycolytic pathway is an important energy source during multiple-nutrient starvation when oxygen is available, and less important under anaerobic conditions. Collectively, the data suggest that the combination of energy-dependent internal adaptation mechanisms

  1. The role of chain carriers in fusion reaction kinetics

    Harms, A.A.; Krenciglowa, E.M.

    1980-01-01

    The role of chain carriers as contributors to multiplicative closed cycles in advanced fusion fuels is examined. Emphasis is placed on rate processes which can be used to characterize critical/supercritical/subcritical tendencies of arbitrary closed fusion cycles. Temporal trajectories for the chain carriers which describe both increasing and decreasing multiplicative processes have been found to exist and identified according to their fusion fuel cycle characteristics. Practical criteria to ensure the attainment of steady-state fusion reaction processes have been formulated in terms of fusion reaction rate relationships. (author)

  2. Multiple cell upset cross-section modeling: A possible interpretation for the role of the ion energy-loss straggling and Auger recombination

    Zebrev, G.I.; Zemtsov, K.S.

    2016-01-01

    We found that the energy deposition fluctuations in the sensitive volumes may cause the multiple cell upset (MCU) multiplicity scatter in the nanoscale (with feature sizes less than 100 nm) memories. A microdosimetric model of the MCU cross-section dependence on LET is proposed. It was shown that ideally a staircase-shaped cross-section vs LET curve spreads due to the energy-loss straggling impact into a quasi-linear dependence with a slope depending on the memory cell area, the cell critical energy and efficiency of charge collection. This paper also presents a new model of the Auger recombination as a limiting process of the electron–hole charge yield, especially at the high-LET ion impact. A modified form of the MCU cross-section vs LET data interpolation is proposed, discussed and validated.

  3. Multiple cell upset cross-section modeling: A possible interpretation for the role of the ion energy-loss straggling and Auger recombination

    Zebrev, G.I., E-mail: gizebrev@mephi.ru; Zemtsov, K.S.

    2016-08-11

    We found that the energy deposition fluctuations in the sensitive volumes may cause the multiple cell upset (MCU) multiplicity scatter in the nanoscale (with feature sizes less than 100 nm) memories. A microdosimetric model of the MCU cross-section dependence on LET is proposed. It was shown that ideally a staircase-shaped cross-section vs LET curve spreads due to the energy-loss straggling impact into a quasi-linear dependence with a slope depending on the memory cell area, the cell critical energy and efficiency of charge collection. This paper also presents a new model of the Auger recombination as a limiting process of the electron–hole charge yield, especially at the high-LET ion impact. A modified form of the MCU cross-section vs LET data interpolation is proposed, discussed and validated.

  4. Quantitative experimental assessment of hot carrier-enhanced solar cells at room temperature

    Nguyen, Dac-Trung; Lombez, Laurent; Gibelli, François; Boyer-Richard, Soline; Le Corre, Alain; Durand, Olivier; Guillemoles, Jean-François

    2018-03-01

    In common photovoltaic devices, the part of the incident energy above the absorption threshold quickly ends up as heat, which limits their maximum achievable efficiency to far below the thermodynamic limit for solar energy conversion. Conversely, the conversion of the excess kinetic energy of the photogenerated carriers into additional free energy would be sufficient to approach the thermodynamic limit. This is the principle of hot carrier devices. Unfortunately, such device operation in conditions relevant for utilization has never been evidenced. Here, we show that the quantitative thermodynamic study of the hot carrier population, with luminance measurements, allows us to discuss the hot carrier contribution to the solar cell performance. We demonstrate that the voltage and current can be enhanced in a semiconductor heterostructure due to the presence of the hot carrier population in a single InGaAsP quantum well at room temperature. These experimental results substantiate the potential of increasing photovoltaic performances in the hot carrier regime.

  5. Magnetic Generation due to Mass Difference between Charge Carriers

    Chen, Shi; Dan, JiaKun; Chen, ZiYu; Li, JianFeng

    2013-01-01

    The possibility of spontaneous magnetization due to the "asymmetry in mass" of charge carriers in a system is investigated. Analysis shows that when the masses of positive and negative charge carriers are identical, no magnetization is predicted. However, if the masses of two species are different, spontaneous magnetic field would appear, either due to the equipartition of magnetic energy or due to fluctuations together with a feedback mechanism. The conditions for magnetization to occur are ...

  6. Electric Vehicles - Promoting Fuel Efficiency and Renewable Energy in Danish Transport

    Jørgensen, Kaj

    1997-01-01

    Analysis of electric vehicles as energy carrier for renewable energy and fossil fuels, including comparisons with other energy carriers (hydrogen, bio-fuels)......Analysis of electric vehicles as energy carrier for renewable energy and fossil fuels, including comparisons with other energy carriers (hydrogen, bio-fuels)...

  7. Energy Security of Army Installations and Islanding Methodologies: A Multiple Criteria Decision Aid to Innovation with Emergent Conditions of the Energy Environment

    2010-06-16

    Clemen and Reilly (2001) Risk analysis Haimes (2009); Kaplan et al. (2001): Lowrance (1976); Kaplan and Garrick (1981) Source: The US Army Energy...collect solar energy and convert to heat (NREL presentation) • Wind turbines capture energy in wind and convert it into electricity (NREL

  8. Annealing behaviour of excess carriers in neutron-transmutation-doped silicon

    Maekawa, T.; Nogami, S.; Inoue, S.

    1993-01-01

    In neutron-transmutation-doped silicon wafers excess carriers are clearly generated over the transmuted phosphorus atoms. The generation occurs for annealing temperatures above 900 o C. The maximum percentage of excess carriers obtained is about 24.5% of the final carrier concentration. Due to the difference in energy of generation and removal, the excess carriers can be removed by annealing above 800 o C. The radiation damage responsible for generation of excess carriers is fairly thermostable in the range of annealing temperatures below 800 o C. From deep-level transient spectroscopy measurements, it is found that the radiation damage remains insensitive to changes in carrier concentration. The activation energies of excess carrier generation and removal are estimated from the analysis of the thermal and temporal behaviours of radiation damage in the annealing process. (Author)

  9. The Optimization Based Dynamic and Cyclic Working Strategies for Rechargeable Wireless Sensor Networks with Multiple Base Stations and Wireless Energy Transfer Devices

    Ding, Xu; Han, Jianghong; Shi, Lei

    2015-01-01

    In this paper, the optimal working schemes for wireless sensor networks with multiple base stations and wireless energy transfer devices are proposed. The wireless energy transfer devices also work as data gatherers while charging sensor nodes. The wireless sensor network is firstly divided into sub networks according to the concept of Voronoi diagram. Then, the entire energy replenishing procedure is split into the pre-normal and normal energy replenishing stages. With the objective of maximizing the sojourn time ratio of the wireless energy transfer device, a continuous time optimization problem for the normal energy replenishing cycle is formed according to constraints with which sensor nodes and wireless energy transfer devices should comply. Later on, the continuous time optimization problem is reshaped into a discrete multi-phased optimization problem, which yields the identical optimality. After linearizing it, we obtain a linear programming problem that can be solved efficiently. The working strategies of both sensor nodes and wireless energy transfer devices in the pre-normal replenishing stage are also discussed in this paper. The intensive simulations exhibit the dynamic and cyclic working schemes for the entire energy replenishing procedure. Additionally, a way of eliminating “bottleneck” sensor nodes is also developed in this paper. PMID:25785305

  10. The optimization based dynamic and cyclic working strategies for rechargeable wireless sensor networks with multiple base stations and wireless energy transfer devices.

    Ding, Xu; Han, Jianghong; Shi, Lei

    2015-03-16

    In this paper, the optimal working schemes for wireless sensor networks with multiple base stations and wireless energy transfer devices are proposed. The wireless energy transfer devices also work as data gatherers while charging sensor nodes. The wireless sensor network is firstly divided into sub networks according to the concept of Voronoi diagram. Then, the entire energy replenishing procedure is split into the pre-normal and normal energy replenishing stages. With the objective of maximizing the sojourn time ratio of the wireless energy transfer device, a continuous time optimization problem for the normal energy replenishing cycle is formed according to constraints with which sensor nodes and wireless energy transfer devices should comply. Later on, the continuous time optimization problem is reshaped into a discrete multi-phased optimization problem, which yields the identical optimality. After linearizing it, we obtain a linear programming problem that can be solved efficiently. The working strategies of both sensor nodes and wireless energy transfer devices in the pre-normal replenishing stage are also discussed in this paper. The intensive simulations exhibit the dynamic and cyclic working schemes for the entire energy replenishing procedure. Additionally, a way of eliminating "bottleneck" sensor nodes is also developed in this paper.

  11. Replica exchange enveloping distribution sampling (RE-EDS): A robust method to estimate multiple free-energy differences from a single simulation.

    Sidler, Dominik; Schwaninger, Arthur; Riniker, Sereina

    2016-10-21

    In molecular dynamics (MD) simulations, free-energy differences are often calculated using free energy perturbation or thermodynamic integration (TI) methods. However, both techniques are only suited to calculate free-energy differences between two end states. Enveloping distribution sampling (EDS) presents an attractive alternative that allows to calculate multiple free-energy differences in a single simulation. In EDS, a reference state is simulated which "envelopes" the end states. The challenge of this methodology is the determination of optimal reference-state parameters to ensure equal sampling of all end states. Currently, the automatic determination of the reference-state parameters for multiple end states is an unsolved issue that limits the application of the methodology. To resolve this, we have generalised the replica-exchange EDS (RE-EDS) approach, introduced by Lee et al. [J. Chem. Theory Comput. 10, 2738 (2014)] for constant-pH MD simulations. By exchanging configurations between replicas with different reference-state parameters, the complexity of the parameter-choice problem can be substantially reduced. A new robust scheme to estimate the reference-state parameters from a short initial RE-EDS simulation with default parameters was developed, which allowed the calculation of 36 free-energy differences between nine small-molecule inhibitors of phenylethanolamine N-methyltransferase from a single simulation. The resulting free-energy differences were in excellent agreement with values obtained previously by TI and two-state EDS simulations.

  12. Observations and modelling of shoreline and multiple sandbar behaviour on a high-energy meso-tidal beach

    Splinter, Kristen D.; Gonzalez, Maria V. G.; Oltman-Shay, Joan; Rutten, Jantien; Holman, Robert

    2018-05-01

    This contribution describes 10 years of observed sandbar and shoreline cross-shore position variability at a meso-tidal, high energy, multiple sandbar beach. To examine relationships between the temporal variability in shoreline/sandbar position with offshore wave forcing, a simple equilibrium model is applied to these data. The analysis presented in this paper shows that the equilibrium model is skilled at predicting the alongshore-averaged, time-varying position of the shoreline (R = 0.82) and the outer sandbar position (R = 0.75), suggesting that these end members of the nearshore sediment system are most strongly influenced by offshore wave forcing in a predictable, equilibrium-forced manner. The middle and inner bars are hypothesized to act as sediment transport pathways between the shoreline and the outer bar. Prediction of these more transient features by an equilibrium model was less skilful. Model coefficients reveal that these two end members (outer bar and shoreline) in the sediment system act in opposite directions to changes in the annual offshore wave forcing. During high wave events, sediment is removed from the shoreline and deposited in the nearshore sediment system with simultaneous landward retreat of the shoreline and offshore migration of the outer sandbar. While both end member features have cycles at annual and inter-annual scales, their respective equilibrium response factor differs by almost a factor of 10, with the shoreline responding around an inter-annual mean (ϕ = 1000 days) and the outer bar responding around a seasonal mean (ϕ = 170 days). The model accurately predicts shoreline response to both mild (e.g. 2004/05, 2008/09) and extreme (e.g. 2005/06, 2009/10) winter storms, as well as their summer recovery. The more mobile and dynamic outer sandbar is well-modelled during typical winters. Summer onshore sandbar migration of the outer bar in 2005 and 2006 is under-predicted as the system transitioned between a triple (winter) and

  13. Carrier-free, functionalized pure drug nanorods as a novel cancer-targeted drug delivery platform

    Li Yanan; An Feifei; Zhang Xiaohong; Yang Yinlong; Liu Zhuang; Zhang Xiujuan

    2013-01-01

    A one-dimensional drug delivery system (1D DDS) is highly attractive since it has distinct advantages such as enhanced drug efficiency and better pharmacokinetics. However, drugs in 1D DDSs are all encapsulated in inert carriers, and problems such as low drug loading content and possible undesirable side effects caused by the carriers remain a serious challenge. In this paper, a novel, carrier-free, pure drug nanorod-based, tumor-targeted 1D DDS has been developed. Drugs are first prepared as nanorods and then surface functionalized to achieve excellent water dispersity and stability. The resulting drug nanorods show enhanced internalization rates mainly through energy-dependent endocytosis, with the shape-mediated nanorod (NR) diffusion process as a secondary pathway. The multiple endocytotic mechanisms lead to significantly improved drug efficiency of functionalized NRs with nearly ten times higher cytotoxicity than those of free molecules and unfunctionalized NRs. A targeted drug delivery system can be readily achieved through surface functionalization with targeting group linked amphipathic surfactant, which exhibits significantly enhanced drug efficacy and discriminates between cell lines with high selectivity. These results clearly show that this tumor-targeting DDS demonstrates high potential toward specific cancer cell lines. (paper)

  14. Application of multiple-point geostatistics to simulate the effect of small-scale aquifer heterogeneity on the efficiency of aquifer thermal energy storage

    Possemiers, Mathias; Huysmans, Marijke; Batelaan, Okke

    2015-08-01

    Adequate aquifer characterization and simulation using heat transport models are indispensible for determining the optimal design for aquifer thermal energy storage (ATES) systems and wells. Recent model studies indicate that meter-scale heterogeneities in the hydraulic conductivity field introduce a considerable uncertainty in the distribution of thermal energy around an ATES system and can lead to a reduction in the thermal recoverability. In a study site in Bierbeek, Belgium, the influence of centimeter-scale clay drapes on the efficiency of a doublet ATES system and the distribution of the thermal energy around the ATES wells are quantified. Multiple-point geostatistical simulation of edge properties is used to incorporate the clay drapes in the models. The results show that clay drapes have an influence both on the distribution of thermal energy in the subsurface and on the efficiency of the ATES system. The distribution of the thermal energy is determined by the strike of the clay drapes, with the major axis of anisotropy parallel to the clay drape strike. The clay drapes have a negative impact (3.3-3.6 %) on the energy output in the models without a hydraulic gradient. In the models with a hydraulic gradient, however, the presence of clay drapes has a positive influence (1.6-10.2 %) on the energy output of the ATES system. It is concluded that it is important to incorporate small-scale heterogeneities in heat transport models to get a better estimate on ATES efficiency and distribution of thermal energy.

  15. Application of multiple-point geostatistics to simulate the effect of small scale aquifer heterogeneity on the efficiency of Aquifer Thermal Energy Storage (ATES)

    Possemiers, Mathias; Huysmans, Marijke; Batelaan, Okke

    2015-04-01

    Adequate aquifer characterization and simulation using heat transport models are indispensible for determining the optimal design for Aquifer Thermal Energy Storage (ATES) systems and wells. Recent model studies indicate that meter scale heterogeneities in the hydraulic conductivity field introduce a considerable uncertainty in the distribution of thermal energy around an ATES system and can lead to a reduction in the thermal recoverability. In this paper, the influence of centimeter scale clay drapes on the efficiency of a doublet ATES system and the distribution of the thermal energy around the ATES wells are quantified. Multiple-point geostatistical simulation of edge properties is used to incorporate the clay drapes in the models. The results show that clay drapes have an influence both on the distribution of thermal energy in the subsurface and on the efficiency of the ATES system. The distribution of the thermal energy is determined by the strike of the clay drapes, with the major axis of anisotropy parallel to the clay drape strike. The clay drapes have a negative impact (3.3 - 3.6%) on the energy output in the models without a hydraulic gradient. In the models with a hydraulic gradient, however, the presence of clay drapes has a positive influence (1.6 - 10.2%) on the energy output of the ATES system. It is concluded that it is important to incorporate small scale heterogeneities in heat transport models to get a better estimate on ATES efficiency and distribution of thermal energy.

  16. LIQUIFIED NATURAL GAS (LNG) CARRIERS

    Daniel Posavec; Katarina Simon; Matija Malnar

    2010-01-01

    Modern liquefied natural gas carriers are double-bottom ships classified according to the type of LNG tank. The tanks are specially designed to store natural gas cooled to -161°C, the boiling point of methane. Since LNG is highly flammable, special care must be taken when designing and operating the ship. The development of LNG carriers has begun in the middle of the twentieth century. LNG carrier storage space has gradually grown to the current maximum of 260000 m3. There are more than 300 L...

  17. Impact of carriers in oral absorption

    Gram, Luise Kvisgaard; Rist, Gerda Marie; Lennernäs, Hans

    2009-01-01

    Carriers may mediate the permeation across enterocytes for drug substances being organic anions. Carrier mediated permeation for the organic anions estrone-3-sulfate (ES) and glipizide across Caco-2 cells were investigated kinetically, and interactions on involved carriers evaluated. Initial...

  18. 7 CFR 35.4 - Carrier.

    2010-01-01

    ... AND PLUMS Definitions § 35.4 Carrier. Carrier means any common or private carrier, including, but not being limited to, trucks, rail, airplanes, vessels, tramp or chartered steamers, whether carrying for...

  19. Basic Stand Alone Carrier Line Items PUF

    U.S. Department of Health & Human Services — This release contains the Basic Stand Alone (BSA) Carrier Line Items Public Use Files (PUF) with information from Medicare Carrier claims. The CMS BSA Carrier Line...

  20. Poisson-like shape and shoulder structure of hadron multiplicity distributions in e+e- annihilation at Z0 energy region

    Xie Yigang; Chai Yong

    1994-01-01

    The charged multiplicity distributions of hadron final states in the e + e - annihilation at the 91.2 GeV Z 0 energy region are fitted with Poisson shape in different rapidity windows for double and single hemisphere. The multiplicities which are in Poisson-like shapes can be got according to the parameter /D and fitting qualities are compared with the results derived from the relevant theoretical models. The relationship between the Poisson-like shape and KNO scaling is discussed. The connection between the parameters expressing the deviation from the Poisson shape and non-independent particle emission and multiplicity correlation strength is analyzed. The 'shoulder structure' is observed in the central rapidity region and analyzed with multi-jets by using the JADE jet analysis algorithm