WorldWideScience

Sample records for single reheat cycle

  1. Method for operating a steam turbine of the nuclear type with electronic reheat control of a cycle steam reheater

    International Nuclear Information System (INIS)

    Luongo, M.C.

    1975-01-01

    An electronic system is provided for operating a nuclear electric power plant with electronic steam reheating control applied to the nuclear turbine system in response to low pressure turbine temperatures, and the control is adapted to operate in a plurality of different automatic control modes to control reheating steam flow and other steam conditions. Each of the modes of control permit turbine temperature variations within predetermined constraints and according to predetermined functions of time. (Official Gazette)

  2. Power and efficiency in a regenerative gas-turbine cycle with multiple reheating and intercooling stages

    Science.gov (United States)

    Calvo Hernández, A.; Roco, J. M. M.; Medina, A.

    1996-06-01

    Using an improved Brayton cycle as a model, a general analysis accounting for the efficiency and net power output of a gas-turbine power plant with multiple reheating and intercooling stages is presented. This analysis provides a general theoretical tool for the selection of the optimal operating conditions of the heat engine in terms of the compressor and turbine isentropic efficiencies and of the heat exchanger efficiency. Explicit results for the efficiency, net power output, optimized pressure ratios, maximum efficiency, maximum power, efficiency at maximum power, and power at maximum efficiency are given. Among others, the familiar results of the Brayton cycle (one compressor and one turbine) and of the corresponding Ericsson cycle (infinite compressors and infinite turbines) are obtained as particular cases.

  3. Design calculation of three-loop combined-cycle plants with steam reheating

    Science.gov (United States)

    Trukhnii, A. D.; Parshina, N. S.

    2010-02-01

    We describe a procedure for carrying out an end-to-end calculation of the parameters of media and technical and economic indicators of three-loop heat-recovery-type combined-cycle plants with steam reheating that makes it possible to determine the parameters of gases and working fluid of a heat-recovery boiler and the thermal power of its heating surfaces, and to carry out an approximate calculation of the steam turbine for compartments and then for stages at the stage of design calculations using the parameters of gases exhausted from the gas turbine unit as initial data. The procedure is implemented in the form of a computer program in the DELPHI environment and makes it possible to quickly and reliably optimize a combined-cycle plant’s thermal circuit and steam turbine design.

  4. Optimization of advanced high-temperature Brayton cycles with multiple reheat stages

    International Nuclear Information System (INIS)

    Haihua Zhao; Per F Peterson

    2005-01-01

    Full text of publication follows: This paper presents an overview and a few point designs for multiple-reheat Brayton cycle power conversion systems using high temperature molten salts (or liquid metals). All designs are derived from the General Atomics GT-MHR power conversion unit (PCU). The GT-MHR PCU is currently the only closed helium cycle system that has undergone detailed engineering design analysis, and that has turbomachinery which is sufficiently large to extrapolate to a >1000 MW(e) multiple reheat gas cycle power conversion system. Analysis shows that, with relatively small engineering modifications, multiple GT-MHR PCU's can be connected together to create a power conversion system in the >1000 MW(e) class. The resulting power conversion system is quite compact, and results in what is likely the minimum gas duct volume possible for a multiple-reheat system. To realize this, compact offset fin plate type liquid-to-gas heat exchangers (power densities from 10 to 120 MW/m 3 ) are needed. Both metal and non-metal heat exchangers are being investigated for high-temperature, gas-cooled reactors for temperatures to 1000 deg. C. Recent high temperature heat exchanger studies for nuclear hydrogen production has suggested that carbon-coated composite materials such as liquid silicon infiltrated chopped fiber carbon-carbon preformed material potentially could be used to fabricate plate fin heat exchangers with reasonable price. Different fluids such as helium, nitrogen and helium mixture, and supercritical CO 2 are compared for these multiple reheat Brayton cycles. Nitrogen and helium mixture cycle need about 40% more total PCU volume than helium cycle while keeping the same net cycle efficiency. Supercritical CO 2 needs very high pressure to optimize. Due to relatively detailed design for components such as heat exchangers, turbomachinery, and duct system, relatively accurate total pressure loss can be obtained, which results in more credible net efficiency

  5. Study on effective parameter of the triple-pressure reheat combined cycle performance

    Directory of Open Access Journals (Sweden)

    Ibrahim Thamir K.

    2013-01-01

    Full Text Available The thermodynamic analyses of the triple-pressure reheat combined cycle gas turbines with duct burner are presented and discussed in this paper. The overall performance of a combined cycle gas turbine power plant is influenced by the ambient temperature, compression ratio and turbine inlet temperature. These parameters affect the overall thermal efficiency, power output and the heat-rate. In this study a thermodynamic model was development on an existing actual combined cycle gas turbine (CCGT (In this case study, an effort has been made to enhance the performance of the CCGT through a parametric study using a thermodynamic analysis. The effect of ambient temperature and operation parameter, including compression ratio and turbine inlet temperature, on the overall performance of CCGT are investigated. The code of the performance model for CCGT power plant was developed utilizing the THERMOFLEX software. The simulating results show that the total power output and overall efficiency of a CCGT decrease with increase the ambient temperature because increase the consumption power in the air compressor of a GT. The totals power of a CCGT decreases with increase the compression rate, while the overall efficiency of a CCGT increases with increase the compression ratio to 21, after that the overall efficiency will go down. Far there more the turbine inlet temperature increases the both total power and overall efficiency increase, so the turbine inlet temperature has a strong effect on the overall performance of CCGT power plant. Also the simulation model give a good result compared with MARAFIQ CCGT power plant. With these variables, the turbine inlet temperature causes the greatest overall performance variation.

  6. Apparatus and methods of reheating gas turbine cooling steam and high pressure steam turbine exhaust in a combined cycle power generating system

    Science.gov (United States)

    Tomlinson, Leroy Omar; Smith, Raub Warfield

    2002-01-01

    In a combined cycle system having a multi-pressure heat recovery steam generator, a gas turbine and steam turbine, steam for cooling gas turbine components is supplied from the intermediate pressure section of the heat recovery steam generator supplemented by a portion of the steam exhausting from the HP section of the steam turbine, steam from the gas turbine cooling cycle and the exhaust from the HP section of the steam turbine are combined for flow through a reheat section of the HRSG. The reheated steam is supplied to the IP section inlet of the steam turbine. Thus, where gas turbine cooling steam temperature is lower than optimum, a net improvement in performance is achieved by flowing the cooling steam exhausting from the gas turbine and the exhaust steam from the high pressure section of the steam turbine in series through the reheater of the HRSG for applying steam at optimum temperature to the IP section of the steam turbine.

  7. Magnetic reheating

    Science.gov (United States)

    Saga, Shohei; Tashiro, Hiroyuki; Yokoyama, Shuichiro

    2018-02-01

    We provide a new bound on the amplitude of primordial magnetic fields (PMFs) by using a novel mechanism, magnetic reheating. The damping of the magnetohydrodynamics fluid motions in a primordial plasma brings the dissipation of the PMFs. In the early Universe with z ≳ 2 × 106, cosmic microwave background (CMB) photons are quickly thermalized with the dissipated energy and shift to a different Planck distribution with a new temperature. In other words, the PMF dissipation changes the baryon-to-photon number ratio, and we name such a process magnetic reheating. From the current baryon-to-photon number ratio obtained from the big bang nucleosynthesis and CMB observations, we put the strongest constraint on the PMFs on small scales which CMB observations cannot access, B0 ≲ 1.0 μG at the scales 104 generation mechanisms of PMFs in the early Universe.

  8. Magnetic reheating

    OpenAIRE

    Saga, Shohei; Tashiro, Hiroyuki; Yokoyama, Shuichiro

    2017-01-01

    We provide a new bound on the amplitude of primordial magnetic fields (PMFs) by using a novel mechanism, named {\\it magnetic reheating}. Before the epoch of recombination, PMFs induce the fluid motions in a photon-baryon plasma through the Lorentz force. Due to the viscosity in the plasma, such induced fluid motions would be damped and this means the dissipation of PMFs. In the early Universe with $z \\gtrsim 2 \\times 10^6$, cosmic microwave background (CMB) photons are quickly thermalized wit...

  9. Reheating after inflation

    International Nuclear Information System (INIS)

    Kripfganz, J.; Ilgenfritz, E.M.

    1985-07-01

    A numerical analysis of reheating is performed for a classical scalar field with exponentially flat potential. An operational definition of the reheating time is given involving the gradient contribution to the inflation field energy. For the parameter range studied the product of reheating time and Hubble constant H is found to be of order one, being approximately independent of the value of H. (author)

  10. Reheating stage after inflation

    International Nuclear Information System (INIS)

    Kolb, Edward W.; Notari, Alessio; Riotto, Antonio

    2003-01-01

    We point out that inflaton decay products acquire plasma masses during the reheating phase following inflation. The plasma masses may render inflaton decay kinematically forbidden, causing the temperature to remain frozen for a period at a plateau value. We show that the final reheating temperature may be uniquely determined by the inflaton mass, and may not depend on its coupling. Our findings have important implications for the thermal production of dangerous relics during reheating (e.g., gravitinos), for extracting bounds on particle physics models of inflation from cosmic microwave background anisotropy data, for the production of massive dark matter candidates during reheating, and for models of baryogenesis or leptogenesis where massive particles are produced during reheating

  11. Observing inflationary reheating.

    Science.gov (United States)

    Martin, Jérôme; Ringeval, Christophe; Vennin, Vincent

    2015-02-27

    Reheating is the epoch which connects inflation to the subsequent hot big-bang phase. Conceptually very important, this era is, however, observationally poorly known. We show that the current Planck satellite measurements of the cosmic microwave background (CMB) anisotropies constrain the kinematic properties of the reheating era for most of the inflationary models. This result is obtained by deriving the marginalized posterior distributions of the reheating parameter for about 200 models of slow-roll inflation. Weighted by the statistical evidence of each model to explain the data, we show that the Planck 2013 measurements induce an average reduction of the posterior-to-prior volume by 40%. Making some additional assumptions on reheating, such as specifying a mean equation of state parameter, or focusing the analysis on peculiar scenarios, can enhance or reduce this constraint. Our study also indicates that the Bayesian evidence of a model can substantially be affected by the reheating properties. The precision of the current CMB data is therefore such that estimating the observational performance of a model now requires incorporating information about its reheating history.

  12. Viability study for application of combined reheater cycle (CRC) to fluidized bed combustion plants; Estudio de Viabilidad para la Aplicacion del Ciclo de Recalentamiento Combinado (CRC) a Plantas de Combustion de Lecho Fuido Atmosferico

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-12-01

    Basically, the project try to analyze the application viability of a first reheating in steam cycles of little power plants, useful mainly for biomass and wastes, in our case with coal blends; and a second reheating of the steam in conventional and fluidized bed combustion plants. Using in both cases the thermic energy of the exhaust gases from one gas turbine. The advantages of the CRC cycle are: (1) Reduction of the moisture in the turbine, increasing the energy efficiency and blade protection. (2) To take advantage of the waste gas energy from the gas turbine in optimum way. (3) Great operation flexibility under good efficiency results. In general, the system can use the synergy between gas, coal and waste energies with the highest global efficiency. (Author)

  13. Probing reheating with primordial spectrum

    International Nuclear Information System (INIS)

    Gong, Jinn-Ouk; Leung, Godfrey; Pi, Shi

    2015-01-01

    We study the impacts of reheating temperature on the inflationary predictions of the spectral index and tensor-to-scalar ratio. Assuming sinusoidal oscillations and that reheating process is very fast, the reheating temperature can be constrained within a factor of 10–100 or even better with the prospect of future observations. Beyond this, we find that the predictions can also be insensitive to the reheating temperature in certain models, including Higgs inflation

  14. Advanced steel reheat furnace

    Energy Technology Data Exchange (ETDEWEB)

    Moyeda, D.; Sheldon, M.; Koppang, R. [Energy and Environmental Research Corp., Irvine, CA (United States); Lanyi, M.; Li, X.; Eleazer, B. [Air Products and Chemicals, Inc., Allentown, PA (United States)

    1997-10-01

    Energy and Environmental Research Corp. (EER) under a contract from the Department of Energy is pursuing the development and demonstration of an Advanced Steel Reheating Furnace. This paper reports the results of Phase 1, Research, which has evaluated an advanced furnace concept incorporating two proven and commercialized technologies previously applied to other high temperature combustion applications: EER`s gas reburn technology (GR) for post combustion NOx control; and Air Product`s oxy-fuel enrichment air (OEA) for improved flame heat transfer in the heating zones of the furnace. The combined technologies feature greater production throughput with associated furnace efficiency improvements; lowered NOx emissions; and better control over the furnace atmosphere, whether oxidizing or reducing, leading to better control over surface finish.

  15. Intrinsic chirp of single-cycle pulses

    International Nuclear Information System (INIS)

    Lin Qiang; Zheng Jian; Dai Jianming; Ho, I-Chen; Zhang, X.-C.

    2010-01-01

    The Fourier transform-limited electromagnetic pulse has been regarded to be free of chirps for a long time. This is no longer true if the pulse duration goes down to or less than one optical cycle. We report the experimental observation of intrinsic chirps in such pulses with the sub-single-cycle terahertz (THz) waveforms obtained with a standard THz time-domain spectroscopy system. The results confirm the break down of the carrier-envelope (CE) expression for single-cycle optical pulses, and may influence the experimental measurements and theoretical modeling with single-cycle pulses.

  16. Thermodynamic Performance of an Internal Reheat Gas Turbine (IRGT) with Hydrogen Combustion

    OpenAIRE

    Katsuhide, HIRAOKA; Teruo, MORISHITA; Susumu, KAN; Power and Energy Engineering Division; Power and Energy Engineering Division; Power and Energy Engineering Division

    1987-01-01

    Combustion of hydrogen gas fuel between blade rows realizes the internal reheat gas turbine (IRGT), which can be extended to a multi stage reheat gas turbine. Thermodynamic analysis was performed on three kinds of multi-stage reheat gas turbine cycles with regenerator. The first one is a regenerative reheat gas turbine system with a hydrogen gas preheater and a steam generator. The second one is the first one with a steam injection at the exit of compressor. The third one is the first one com...

  17. Gravitational reheating in quintessential inflation

    International Nuclear Information System (INIS)

    Scopel, Stefano

    2010-01-01

    Quintessential inflation assumes a common origin for inflation and the dark energy of the Universe. In this scenario reheating can occur through gravitational particle production during the inflation-kination transition. We provide a detailed study of gravitational reheating in quintessential inflation and determine the temperature T * at which radiation starts dominating over kination, generalizing previous analyses only available for the standard case when inflation is followed by an era dominated by the energy density of radiation, The value of T * is controlled by the Hubble parameter H 0 during inflation and the transition time Δt, scaling as H 0 2 [ln(1/H 0 Δt)] 3/4 for H 0 Δt 0 2 (H 0 Δt) -c for H 0 t >> 1. The model-dependent parameter c is found to be around 0.5 in two different parametrizations for the transition between inflation and kination.

  18. Curvaton reheating: An application to braneworld inflation

    International Nuclear Information System (INIS)

    Liddle, Andrew R.; Urena-Lopez, L. Arturo

    2003-01-01

    The curvaton was introduced recently as a distinct inflationary mechanism for generating adiabatic density perturbations. Implicit in that scenario is that the curvaton offers a new mechanism for reheating after inflation, as it is a form of energy density not diluted by the inflationary expansion. We consider curvaton reheating in the context of a braneworld inflation model, steep inflation, which features a novel use of the braneworld to give a new mechanism for ending inflation. The original steep inflation model featured reheating by gravitational particle production, but the inefficiency of that process causes observational difficulties. We demonstrate here that the phenomenology of steep inflation is much improved by curvaton reheating

  19. Selection of optimal reheat temperature in heat recovery boiler at combined heat and power plant with GT-topping

    Directory of Open Access Journals (Sweden)

    Romashova Olga

    2017-01-01

    Full Text Available Calculations to determine optimum value of steam reheat temperature in relation to the cycle arrangement of steam turbine power plant with gas turbine topping are conducted in this paper. Operation of T-250-240 turbine unit in cogeneration mode has been considered during steam reheat displacement from steam boiler to heat recovery boiler.

  20. Gravitational reheating in quintessential inflation

    International Nuclear Information System (INIS)

    Chun, E.J.; Zaballa, I.; Scopel, S.

    2009-01-01

    We provide a detailed study of gravitational reheating in quintessential inflation generalizing previous analyses only available for the standard case when inflation is followed by an era dominated by the energy density of radiation. Quintessential inflation assumes a common origin for inflation and the dark energy of the Universe. In this scenario reheating can occur through gravitational particle production during the inflation-kination transition. We calculate numerically the amount of the radiation energy density, and determine the temperature T * at which radiation starts dominating over kination. The value of T * is controlled by the Hubble parameter H 0 during inflation and the transition time Δt, scaling as H 0 2 [ln(1/H 0 Δt)] 3/4 for H 0 Δt 0 2 (H 0 Δt) −c for H 0 Δt >> 1. The model-dependent parameter c is found to be around 0.5 in two different parameterizations for the transition between inflation and kination

  1. Reheating of the Universe as holographic thermalization

    Energy Technology Data Exchange (ETDEWEB)

    Kawai, Shinsuke, E-mail: shinsuke.kawai@gmail.com [Department of Physics, Sungkyunkwan University, Suwon 16419 (Korea, Republic of); Nakayama, Yu [California Institute of Technology, 452-48, Pasadena, CA 91125 (United States); Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, Kashiwa, Chiba 277-8583 (Japan)

    2016-08-10

    Assuming gauge/gravity correspondence we study reheating of the Universe using its holographic dual. Inflaton decay and thermalisation of the decay products correspond to collapse of a spherical shell and formation of a blackhole in the dual anti-de Sitter (AdS) spacetime. The reheating temperature is computed as the Hawking temperature of the developed blackhole probed by a dynamical boundary, and is determined by the inflaton energy density and the AdS radius, with corrections from the dynamics of the shell collapse. For given initial energy density of the inflaton field the holographic model typically gives lower reheating temperature than the instant reheating scenario, while it is shown to be safely within phenomenological bounds.

  2. Reheating of the Universe as holographic thermalization

    Directory of Open Access Journals (Sweden)

    Shinsuke Kawai

    2016-08-01

    Full Text Available Assuming gauge/gravity correspondence we study reheating of the Universe using its holographic dual. Inflaton decay and thermalisation of the decay products correspond to collapse of a spherical shell and formation of a blackhole in the dual anti-de Sitter (AdS spacetime. The reheating temperature is computed as the Hawking temperature of the developed blackhole probed by a dynamical boundary, and is determined by the inflaton energy density and the AdS radius, with corrections from the dynamics of the shell collapse. For given initial energy density of the inflaton field the holographic model typically gives lower reheating temperature than the instant reheating scenario, while it is shown to be safely within phenomenological bounds.

  3. Reheating of zinc-titanate sintered specimens

    Directory of Open Access Journals (Sweden)

    Labus N.

    2015-01-01

    Full Text Available The scope of this work was observing dimensional and heat transfer changes in ZnTiO3 samples during heating in nitrogen and air atmosphere. Interactions of bulk specimens with gaseous surrounding induce microstructure changes during heating. Sintered ZnTiO3 nanopowder samples were submitted to subsequent heating. Dilatation curves and thermogravimetric with simultaneous differential thermal analysis TGA/DTA curves were recorded. Reheating was performed in air and nitrogen atmospheres. Reheated samples obtained at different characteristic temperatures in air were analyzed by X-ray diffraction (XRD. Microstructures obtained by scanning electron microscopy (SEM of reheated sintered samples are presented and compared. Reheating in a different atmosphere induced different microstructures. The goal was indicating possible causes leading to the microstructure changes. [Projekat Ministarstva nauke Republike Srbije, br. OI172057 i br. III45014

  4. Moisture separator reheaters for nuclear power plants

    International Nuclear Information System (INIS)

    Miyoshi, Michizo; Yonemura, Katsutoshi

    1974-01-01

    In the light water reactor plants using BWRS or PWRS, the pressure and temperature of steam at the inlet of turbines are low, and the steam is moist, as compared with the case of thermal power plants. Therefore, moisture separator/reheaters are used between high and low pressure turbines. The steam from a high pressure turbine enters a manifold, and goes zigzag through vertical plate separator elements, its moisture is removed from the steam. Then, after being reheated with the steam bled from the high pressure turbine and directly from a reactor, the steam is fed into a low pressure turbine. The development and test made on the components of a moisture separaotr/reheater and the overall model experiment are described together with the mechanism of moisture separation and reheating. (Mori, K.)

  5. Steep inflation followed by Born-Infeld reheating

    International Nuclear Information System (INIS)

    Sami, M.; Dadhich, N.; Shiromizu, Tetsuya

    2003-01-01

    We discuss a model in which high energy brane corrections allow a single scalar field to describe inflation at early epochs and quintessence at late times. The reheating mechanism in the model originates from Born-Infeld matter whose energy density mimics cosmological constant at very early times and manifests itself as radiation subsequently. During the inflationary evolution the Born-Infeld matter remains sub-dominant to the scalar field. Shortly before the end of inflation driven by the scalar field, the energy density of Born-Infeld matter starts scaling as radiation and drops by several orders of magnitudes at the epoch inflation ends. The problem of over production of gravity wave background in scenarios based upon reheating through gravitational particle production is successfully resolved by suitably fixing the initial value of radiation energy density at the end of inflation. No additional fine tuning of the parameters is required for a viable evolution

  6. Effect of Dynamic Reheating Induced by Weaving on the Microstructure of GTAW Weld Metal of 25% Cr Super Duplex Stainless Steel Weld Metal

    Directory of Open Access Journals (Sweden)

    Hee-Joon Sung

    2017-11-01

    Full Text Available The importance of the additional growth and/or transformation of the austenite phase that occurs in weld metals of super duplex stainless steel upon reheating is known. However, the effects have not been fully investigated, especially with respect to reheating induced by weaving during single-pass welding. In this work, bead-on-pipe gas tungsten arc welding (GTAW was conducted on super duplex stainless steel to understand the effect of weaving on the microstructure of weld metal. Microstructural analysis, electron backscatter diffraction (EBSD, and focused ion beam transmission electron microscopy (FIB-TEM were carried out to investigate the relationship between weaving and microstructural change. The weaving of GTAW produced a dynamic reheated area just before the weld bead during welding. It was revealed that extensive reheated weld existed even after one welding pass, and that the content of the austenite phase in the reheated area was higher than that in the non-reheated area, indicating the existence of a large quantity of intragranular austenite phase. In addition, the Cr2N content in the reheated area was lower than that in the non-reheated area. This reduction of Cr2N was closely related to the reheating resulting from weaving. TEM analysis revealed that Cr2N in the non-reheated area was dispersed following heating and transformed to secondary austenite.

  7. Optimum gas turbine cycle for combined cycle power plant

    International Nuclear Information System (INIS)

    Polyzakis, A.L.; Koroneos, C.; Xydis, G.

    2008-01-01

    The gas turbine based power plant is characterized by its relatively low capital cost compared with the steam power plant. It has environmental advantages and short construction lead time. However, conventional industrial engines have lower efficiencies, especially at part load. One of the technologies adopted nowadays for efficiency improvement is the 'combined cycle'. The combined cycle technology is now well established and offers superior efficiency to any of the competing gas turbine based systems that are likely to be available in the medium term for large scale power generation applications. This paper has as objective the optimization of a combined cycle power plant describing and comparing four different gas turbine cycles: simple cycle, intercooled cycle, reheated cycle and intercooled and reheated cycle. The proposed combined cycle plant would produce 300 MW of power (200 MW from the gas turbine and 100 MW from the steam turbine). The results showed that the reheated gas turbine is the most desirable overall, mainly because of its high turbine exhaust gas temperature and resulting high thermal efficiency of the bottoming steam cycle. The optimal gas turbine (GT) cycle will lead to a more efficient combined cycle power plant (CCPP), and this will result in great savings. The initial approach adopted is to investigate independently the four theoretically possible configurations of the gas plant. On the basis of combining these with a single pressure Rankine cycle, the optimum gas scheme is found. Once the gas turbine is selected, the next step is to investigate the impact of the steam cycle design and parameters on the overall performance of the plant, in order to choose the combined cycle offering the best fit with the objectives of the work as depicted above. Each alterative cycle was studied, aiming to find the best option from the standpoint of overall efficiency, installation and operational costs, maintainability and reliability for a combined power

  8. Moisture separators and reheaters for wet steam turbines

    International Nuclear Information System (INIS)

    Gibbins, J.

    1979-01-01

    Moisture separator reheater (M.S.R.) units are now a well established feature of the wet steam cycle as associated with the various types of water cooled reactor. This paper describes the development of M.S.Rs. as supplied by GEC for turbine generators of up to 1200 MW ratings covering the design procedures used and the features required to ensure efficient and reliable operation. In addition to details of the M.S.R. design, the desirable features of the steam supply, venting and drain control systems are also discussed. The recent developments, as provided on current projects, are described. (author)

  9. Production of massive particles during reheating

    CERN Document Server

    Chung, D J H; Riotto, Antonio; Chung, Daniel J. H.; Kolb, Edward W.; Riotto, Antonio

    1999-01-01

    What is commonly called the reheat temperature, $T_{RH}$, is not the maximum temperature obtained after inflation. The maximum temperature is, in fact, much larger than $T_{RH}$. As an application of this we consider the production of massive stable dark-matter particles of mass $M_X$ during reheating, and show that their abundance is suppressed as a power of $T_{RH}/M_X$ rather than times the reheat temperature may be produced in interesting abundance. In addition to dark matter, our analysis is relevant for baryogenesis if the baryon asymmetry is produced by the baryon (or lepton) number violating decays of superheavy bosons, and also for relic ultra-high energy cosmic rays if decays of superheavy particles are responsible for the highest energy cosmic rays.

  10. Quintessential inflation at low reheating temperatures

    Science.gov (United States)

    Saló, Llibert Aresté; de Haro, Jaume

    2017-11-01

    We have tested some simple quintessential inflation models, imposing the requirement that they match with the recent observational data provided by the BICEP and Planck team and leading to a reheating temperature, which is obtained via gravitational particle production after inflation, supporting the nucleosynthesis success. Moreover, for the models coming from supergravity one needs to demand low temperatures in order to avoid problems such as the gravitino overproduction or the gravitational production of moduli fields, which are obtained only when the reheating temperature is due to the production of massless particles with a coupling constant very close to its conformal value.

  11. Quintessential inflation at low reheating temperatures

    International Nuclear Information System (INIS)

    Salo, Llibert Areste; Haro, Jaume de

    2017-01-01

    We have tested some simple quintessential inflation models, imposing the requirement that they match with the recent observational data provided by the BICEP and Planck team and leading to a reheating temperature, which is obtained via gravitational particle production after inflation, supporting the nucleosynthesis success. Moreover, for the models coming from supergravity one needs to demand low temperatures in order to avoid problems such as the gravitino overproduction or the gravitational production of moduli fields, which are obtained only when the reheating temperature is due to the production of massless particles with a coupling constant very close to its conformal value. (orig.)

  12. Quintessential inflation at low reheating temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Salo, Llibert Areste [Universitat Politecnica de Catalunya, Departament de Matematiques, Barcelona (Spain); Ludwig-Maximilians-Universitaet, Fakultaet fuer Physik, Munich (Germany); Haro, Jaume de [Universitat Politecnica de Catalunya, Departament de Matematiques, Terrassa (Spain)

    2017-11-15

    We have tested some simple quintessential inflation models, imposing the requirement that they match with the recent observational data provided by the BICEP and Planck team and leading to a reheating temperature, which is obtained via gravitational particle production after inflation, supporting the nucleosynthesis success. Moreover, for the models coming from supergravity one needs to demand low temperatures in order to avoid problems such as the gravitino overproduction or the gravitational production of moduli fields, which are obtained only when the reheating temperature is due to the production of massless particles with a coupling constant very close to its conformal value. (orig.)

  13. Curvaton reheating in a logamediate inflationary model

    International Nuclear Information System (INIS)

    Campo, Sergio del; Herrera, Ramon; Saavedra, Joel; Campuzano, Cuauhtemoc; Rojas, Efrain

    2009-01-01

    In a logamediate inflationary universe model we introduce the curvaton field in order to bring this inflationary model to an end. In this approach we determine the reheating temperature. We also outline some interesting constraints on the parameters that describe our models. Thus, we give the parameter space in this scenario.

  14. Quantifying the reheating temperature of the universe

    Directory of Open Access Journals (Sweden)

    Anupam Mazumdar

    2014-09-01

    Full Text Available The aim of this paper is to determine an exact definition of the reheat temperature for a generic perturbative decay of the inflaton. In order to estimate the reheat temperature, there are two important conditions one needs to satisfy: (a the decay products of the inflaton must dominate the energy density of the universe, i.e. the universe becomes completely radiation dominated, and (b the decay products of the inflaton have attained local thermodynamical equilibrium. For some choices of parameters, the latter is a more stringent condition, such that the decay products may thermalise much after the beginning of radiation–domination. Consequently, we have obtained that the reheat temperature can be much lower than the standard-lore estimation. In this paper we describe under what conditions our universe could have efficient or inefficient thermalisation, and quantify the reheat temperature for both the scenarios. This result has an immediate impact on many applications which rely on the thermal history of the universe, in particular gravitino abundance.

  15. Correlation Between Microstructure and Low-Temperature Impact Toughness of Simulated Reheated Zones in the Multi-pass Weld Metal of High-Strength Steel

    Science.gov (United States)

    Kang, Yongjoon; Park, Gitae; Jeong, Seonghoon; Lee, Changhee

    2018-01-01

    A large fraction of reheated weld metal is formed during multi-pass welding, which significantly affects the mechanical properties (especially toughness) of welded structures. In this study, the low-temperature toughness of the simulated reheated zone in multi-pass weld metal was evaluated and compared to that of the as-deposited zone using microstructural analyses. Two kinds of high-strength steel welds with different hardenabilities were produced by single-pass, bead-in-groove welding, and both welds were thermally cycled to peak temperatures above Ac3 using a Gleeble simulator. When the weld metals were reheated, their toughness deteriorated in response to the increase in the fraction of detrimental microstructural components, i.e., grain boundary ferrite and coalesced bainite in the weld metals with low and high hardenabilities, respectively. In addition, toughness deterioration occurred in conjunction with an increase in the effective grain size, which was attributed to the decrease in nucleation probability of acicular ferrite; the main cause for this decrease changed depending on the hardenability of the weld metal.

  16. Numerical analysis method for reheater performance of moisture separator reheater for Nuclear Power Plants

    International Nuclear Information System (INIS)

    Oda, Tsuyoshi; Fujisawa, Kyosuke; Akamatsu, Hiroshi

    2014-01-01

    Nuclear power generation uses saturated steam of 6 MPa and 275degC level due to the restrictions imposed by the materials used in the nuclear reactor, and its efficiency, approximately 33-35%, is not high compared with fossil fuel power generation. Therefore, thermal engineers working on nuclear power generation have the important responsibility toward society of achieving the highest efficiency under the given restrictions. The use of a moisture separator reheater (MSR) is one of the measures we can take to achieve higher efficiency. Because the bottom of the MSR tube bundle making contact with the cycle steam at its lowest temperature is subcooled and inadequate drainage of the condensate inside the tubes causes cyclic flooding and temperature oscillations in some cases, it is necessary to have a minimum flow rate of excess heating steam slightly beyond the demand of/what is required for the heat transfer, and the consequent subcooling must be kept below a certain level. This report describes the numerical analysis method developed for the design of heat transfer performance and evaluation of the tube bundle integrity of MSRs. (author)

  17. Next generation GNSS single receiver cycle slip reliability

    NARCIS (Netherlands)

    Teunissen, P.J.G.; De Bakker, P.F.

    2009-01-01

    In this contribution we study the multi-frequency, carrier-phase slip detection capabilities of a single receiver. Our analysis is based on an analytical expression that we present for themulti-frequencyminimal detectable carrier phase cycle slip.

  18. Primordial magnetic field amplification from turbulent reheating

    International Nuclear Information System (INIS)

    Calzetta, Esteban; Kandus, Alejandra

    2010-01-01

    We analyze the possibility of primordial magnetic field amplification by a stochastic large scale kinematic dynamo during reheating. We consider a charged scalar field minimally coupled to gravity. During inflation this field is assumed to be in its vacuum state. At the transition to reheating the state of the field changes to a many particle/anti-particle state. We characterize that state as a fluid flow of zero mean velocity but with a stochastic velocity field. We compute the scale-dependent Reynolds number Re(k), and the characteristic times for decay of turbulence, t d and pair annihilation t a , finding t a d . We calculate the rms value of the kinetic helicity of the flow over a scale L and show that it does not vanish. We use this result to estimate the amplification factor of a seed field from the stochastic kinematic dynamo equations. Although this effect is weak, it shows that the evolution of the cosmic magnetic field from reheating to galaxy formation may well be more complex than as dictated by simple flux freezing

  19. On the performance simulation of inter-stage turbine reheat

    International Nuclear Information System (INIS)

    Pellegrini, Alvise; Nikolaidis, Theoklis; Pachidis, Vassilios; Köhler, Stephan

    2017-01-01

    Highlights: • An innovative gas turbine performance simulation methodology is proposed. • It allows to perform DP and OD performance calculations for complex engines layouts. • It is essential for inter-turbine reheat (ITR) engine performance calculation. • A detailed description is provided for fast and flexible implementation. • The methodology is successfully verified against a commercial closed-source software. - Abstract: Several authors have suggested the implementation of reheat in high By-Pass Ratio (BPR) aero engines, to improve engine performance. In contrast to military afterburning, civil aero engines would aim at reducing Specific Fuel Consumption (SFC) by introducing ‘Inter-stage Turbine Reheat’ (ITR). To maximise benefits, the second combustor should be placed at an early stage of the expansion process, e.g. between the first and second High-Pressure Turbine (HPT) stages. The aforementioned cycle design requires the accurate simulation of two or more turbine stages on the same shaft. The Design Point (DP) performance can be easily evaluated by defining a Turbine Work Split (TWS) ratio between the turbine stages. However, the performance simulation of Off-Design (OD) operating points requires the calculation of the TWS parameter for every OD step, by taking into account the thermodynamic behaviour of each turbine stage, represented by their respective maps. No analytical solution of the aforementioned problem is currently available in the public domain. This paper presents an analytical methodology by which ITR can be simulated at DP and OD. Results show excellent agreement with a commercial, closed-source performance code; discrepancies range from 0% to 3.48%, and are ascribed to the different gas models implemented in the codes.

  20. Brown Boveri moves to fourth generation MSRs [moisture separator reheaters

    International Nuclear Information System (INIS)

    Boeckh, P. von

    1987-01-01

    The fourth, space saving, generation of moisture separator reheaters from Brown Boveri and Cie (BBC) consists of two types of high velocity moisture separators, 'Mops' and 'Scrups', and the small size reheater, 'Road' . The design of the unit is described, together with operational experience. (author)

  1. Low reheating temperatures in monomial and binomial inflationary models

    International Nuclear Information System (INIS)

    Rehagen, Thomas; Gelmini, Graciela B.

    2015-01-01

    We investigate the allowed range of reheating temperature values in light of the Planck 2015 results and the recent joint analysis of Cosmic Microwave Background (CMB) data from the BICEP2/Keck Array and Planck experiments, using monomial and binomial inflationary potentials. While the well studied ϕ 2 inflationary potential is no longer favored by current CMB data, as well as ϕ p with p>2, a ϕ 1 potential and canonical reheating (w re =0) provide a good fit to the CMB measurements. In this last case, we find that the Planck 2015 68% confidence limit upper bound on the spectral index, n s , implies an upper bound on the reheating temperature of T re ≲6×10 10 GeV, and excludes instantaneous reheating. The low reheating temperatures allowed by this model open the possibility that dark matter could be produced during the reheating period instead of when the Universe is radiation dominated, which could lead to very different predictions for the relic density and momentum distribution of WIMPs, sterile neutrinos, and axions. We also study binomial inflationary potentials and show the effects of a small departure from a ϕ 1 potential. We find that as a subdominant ϕ 2 term in the potential increases, first instantaneous reheating becomes allowed, and then the lowest possible reheating temperature of T re =4 MeV is excluded by the Planck 2015 68% confidence limit

  2. Reheating and gravitino production in braneworld inflation

    International Nuclear Information System (INIS)

    Copeland, Edmund J.; Seto, Osamu

    2005-01-01

    We consider the constraints that can be imposed on a wide class of Inflation models in modified gravity scenarios in which the Friedmann equation is modified by the inclusion of ρ 2 terms, where ρ is the total energy density. In particular we obtain the reheating temperature and gravitino abundance associated with the end of inflation. Whereas models of chaotic inflation and natural inflation can easily avoid the conventional gravitino overproduction problem, we show that supersymmetric hybrid inflation models (driven by both F and D terms) do not work in the ρ 2 dominated era. We also study inflation driven by exponential potentials in this modified background and show that the gravitino production is suppressed enough to avoid there being a problem, although other conditions severely constrain these models

  3. Chilly dark sectors and asymmetric reheating

    International Nuclear Information System (INIS)

    Adshead, Peter; Cui, Yanou; Shelton, Jessie

    2016-01-01

    In a broad class of theories, the relic abundance of dark matter is determined by interactions internal to a thermalized dark sector, with no direct involvement of the Standard Model (SM). We point out that these theories raise an immediate cosmological question: how was the dark sector initially populated in the early universe? Motivated in part by the difficulty of accommodating large amounts of entropy carried in dark radiation with cosmic microwave background measurements of the effective number of relativistic species at recombination, N eff , we aim to establish which admissible cosmological histories can populate a thermal dark sector that never reaches thermal equilibrium with the SM. The minimal cosmological origin for such a dark sector is asymmetric reheating, when the same mechanism that populates the SM in the early universe also populates the dark sector at a lower temperature. Here we demonstrate that the resulting inevitable inflaton-mediated scattering between the dark sector and the SM can wash out a would-be temperature asymmetry, and establish the regions of parameter space where temperature asymmetries can be generated in minimal reheating scenarios. Thus obtaining a temperature asymmetry of a given size either restricts possible inflaton masses and couplings or necessitates a non-minimal cosmology for one or both sectors. As a side benefit, we develop techniques for evaluating collision terms in the relativistic Boltzmann equation when the full dependence on Bose-Einstein or Fermi-Dirac phase space distributions must be retained, and present several new results on relativistic thermal averages in an appendix.

  4. Energetic and exergetic Improvement of geothermal single flash cycle

    Directory of Open Access Journals (Sweden)

    Navid Nazari

    2016-08-01

    Full Text Available This paper presents a detailed analysis of a new method for improving energetic and exergetic efficiencies of single flash cycle. The thermodynamic process of the new method consists of extracting a fraction of hot wellhead geothermal brine for the purpose of superheating saturated steam entering the turbine. Computer programming scripts were developed and optimized based on mathematical proposed models for the different components of the systems. The operating parameters such as separator temperature, geofluid wellhead enthalpy and geothermal source temperature are varied to investigate their effects on both net power output and turbine exhaust quality of the systems. Also, full exergy assessment was performed for the new design. The results of separator temperature optimization revealed that specific net power output of the new design can be boosted up to 8% and turbine exhaust quality can be diminished up to 50% as compared to common single flash cycle. In addition, for wells with higher discharge enthalpy, superheating process improve specific net power output even up to 10%. Finally, it was observed that the overall system exergy efficiency was approximately raised 3%. Article History: Received January 5th 2016; Received in revised form June 25th 2016; Accepted July 3rd 2016; Available online How to Cite This Article: Nazari, N. and Porkhial, S. (2016. Energetic and Exergetic Improvement of Geothermal Single Flash Cycle. Int. Journal of Renewable Energy Development, 5(2,129-138. http://dx.doi.org/10.14710/ijred.5.2.129-138 

  5. Toward an effective field theory approach to reheating

    Science.gov (United States)

    Özsoy, Ogan; Giblin, John T.; Nesbit, Eva; Şengör, Gizem; Watson, Scott

    2017-12-01

    We investigate whether effective field theory (EFT) approaches, which have been useful in examining inflation and dark energy, can also be used to establish a systematic approach to inflationary reheating. We consider two methods. First, we extend Weinberg's background EFT to the end of inflation and reheating. We establish when parametric resonance and decay of the inflaton occurs, but also find intrinsic theoretical limitations, which make it difficult to capture some reheating models. This motivates us to next consider Cheung et al.'s EFT approach, which instead focuses on perturbations and the symmetry breaking induced by the cosmological background. Adapting the latter approach to reheating implies some new and important differences compared to the EFT of inflation. In particular, there are new hierarchical scales, and we must account for inflaton oscillations during reheating, which lead to discrete symmetry breaking. Guided by the fundamental symmetries, we construct the EFT of reheating, and as an example of its usefulness we establish a new class of reheating models and the corresponding predictions for gravity wave observations. In this paper we primarily focus on the first stages of preheating. We conclude by discussing challenges for the approach and future directions. This paper builds on ideas first proposed in the paper [O. Ozsoy, G. Sengor, K. Sinha, and S. Watson, arXiv:1507.06651.].

  6. Effect of reheating on predictions following multiple-field inflation

    Science.gov (United States)

    Hotinli, Selim C.; Frazer, Jonathan; Jaffe, Andrew H.; Meyers, Joel; Price, Layne C.; Tarrant, Ewan R. M.

    2018-01-01

    We study the sensitivity of cosmological observables to the reheating phase following inflation driven by many scalar fields. We describe a method which allows semianalytic treatment of the impact of perturbative reheating on cosmological perturbations using the sudden decay approximation. Focusing on N -quadratic inflation, we show how the scalar spectral index and tensor-to-scalar ratio are affected by the rates at which the scalar fields decay into radiation. We find that for certain choices of decay rates, reheating following multiple-field inflation can have a significant impact on the prediction of cosmological observables.

  7. Imprints of quantum gravity on large field inflation and reheating

    International Nuclear Information System (INIS)

    Rompineve Sorbello, Fabrizio

    2017-01-01

    In this thesis we investigate the feasibility and phenomenology of transplanckian field displacements during Inflation as well as the production of very light fields during Reheating. We begin by focusing on realisations of axion inflation in the complex structure moduli sector of Type IIB String Theory (ST) flux compactifications. Firstly, we analyse the problem of backreaction of complex structure moduli on the inflationary trajectory in a concrete model of axion monodromy inflation. Secondly, we propose a realisation of natural inflation where the inflaton arises as a combination of two axions. In both cases we find sufficiently flat inflationary potentials over a limited, but transplanckian field range. However, our realisation of axion monodromy inflation requires a potentially large, though realisable, number of tunings to ensure that the inflationary shift symmetry is only weakly broken. The consequences of the Weak Gravity Conjecture (WGC) for axion monodromy inflation are then explored. We find that the conjecture provides a bound on the inflationary field range, but does not forbid transplanckian displacements. Moreover, we provide a strategy to generalise the WGC to general p-form gauge theories in ST. Finally, we focus on the physics of the early post-inflationary phase. We show that axion monodromy inflation can lead to a phase decomposition, followed by the radiation of potentially detectable gravitational waves. We also propose a strategy to evade the overproduction of Dark Radiation in the Large Volume Scenario of moduli stabilisation, by means of flavour branes wrapping the bulk cycle of the compactification manifold.

  8. Imprints of quantum gravity on large field inflation and reheating

    Energy Technology Data Exchange (ETDEWEB)

    Rompineve Sorbello, Fabrizio

    2017-04-18

    In this thesis we investigate the feasibility and phenomenology of transplanckian field displacements during Inflation as well as the production of very light fields during Reheating. We begin by focusing on realisations of axion inflation in the complex structure moduli sector of Type IIB String Theory (ST) flux compactifications. Firstly, we analyse the problem of backreaction of complex structure moduli on the inflationary trajectory in a concrete model of axion monodromy inflation. Secondly, we propose a realisation of natural inflation where the inflaton arises as a combination of two axions. In both cases we find sufficiently flat inflationary potentials over a limited, but transplanckian field range. However, our realisation of axion monodromy inflation requires a potentially large, though realisable, number of tunings to ensure that the inflationary shift symmetry is only weakly broken. The consequences of the Weak Gravity Conjecture (WGC) for axion monodromy inflation are then explored. We find that the conjecture provides a bound on the inflationary field range, but does not forbid transplanckian displacements. Moreover, we provide a strategy to generalise the WGC to general p-form gauge theories in ST. Finally, we focus on the physics of the early post-inflationary phase. We show that axion monodromy inflation can lead to a phase decomposition, followed by the radiation of potentially detectable gravitational waves. We also propose a strategy to evade the overproduction of Dark Radiation in the Large Volume Scenario of moduli stabilisation, by means of flavour branes wrapping the bulk cycle of the compactification manifold.

  9. Single Turnover Autophosphorylation Cycle of the PKA RIIβ Holoenzyme.

    Directory of Open Access Journals (Sweden)

    Ping Zhang

    2015-07-01

    Full Text Available To provide tight spatiotemporal signaling control, the cyclic adenosine monophosphate (cAMP-dependent protein kinase (PKA holoenzyme typically nucleates a macromolecular complex or a "PKA signalosome." Using the RIIβ holoenzyme as a prototype, we show how autophosphorylation/dephosphorylation of the RIIβ subunit, as well as cAMP and metal ions, contribute to the dynamics of PKA signaling. While we showed previously that the RIIβ holoenzyme could undergo a single turnover autophosphorylation with adenosine triphosphate and magnesium (MgATP and trap both products in the crystal lattice, we asked here whether calcium could trap an ATP:RIIβ holoenzyme since the RIIβ holoenzyme is located close to ion channels. The 2.8Å structure of an RIIβp2:C2:(Ca2ADP2 holoenzyme, supported by biochemical and biophysical data, reveals a trapped single phosphorylation event similar to MgATP. Thus, calcium can mediate a single turnover event with either ATP or adenosine-5'-(β,γ-imidotriphosphate (AMP-PNP, even though it cannot support steady-state catalysis efficiently. The holoenzyme serves as a "product trap" because of the slow off-rate of the pRIIβ subunit, which is controlled by cAMP, not by phosphorylation of the inhibitor site. By quantitatively defining the RIIβ signaling cycle, we show that release of pRIIβ in the presence of cAMP is reduced by calcium, whereas autophosphorylation at the phosphorylation site (P-site inhibits holoenzyme reassociation with the catalytic subunit. Adding a single phosphoryl group to the preformed RIIβ holoenzyme thus creates a signaling cycle in which phosphatases become an essential partner. This previously unappreciated molecular mechanism is an integral part of PKA signaling for type II holoenzymes.

  10. Device and Container for Reheating and Sterilization

    Science.gov (United States)

    Sastry, Sudhir K.; Heskitt, Brian F.; Jun, Soojin; Marcy, Joseph E.; Mahna, Ritesh

    2012-01-01

    Long-duration space missions require the development of improved foods and novel packages that do not represent a significant disposal issue. In addition, it would also be desirable if rapid heating technologies could be used on Earth as well, to improve food quality during a sterilization process. For this purpose, a package equipped with electrodes was developed that will enable rapid reheating of contents via ohmic heating to serving temperature during space vehicle transit. Further, the package is designed with a resealing feature, which enables the package, once used, to contain and sterilize waste, including human waste for storage prior to jettison during a long-duration mission. Ohmic heating is a technology that has been investigated on and off for over a century. Literature indicates that foods processed by ohmic heating are of superior quality to their conventionally processed counterparts. This is due to the speed and uniformity of ohmic heating, which minimizes exposure of sensitive materials to high temperatures. In principle, the material may be heated rapidly to sterilization conditions, cooled rapidly, and stored. The ohmic heating device herein is incorporated within a package. While this by itself is not novel, a reusable feature also was developed with the intent that waste may be stored and re-sterilized within the packages. These would then serve a useful function after their use in food processing and storage. The enclosure should be designed to minimize mass (and for NASA's purposes, Equivalent System Mass, or ESM), while enabling the sterilization function. It should also be electrically insulating. For this reason, Ultem high-strength, machinable electrical insulator was used.

  11. Enhancement of Heat-Recovery Steam-Gas Plant Efficiency at Expense of Steam Reheating Application

    Directory of Open Access Journals (Sweden)

    A. S. Grinchuk

    2008-01-01

    Full Text Available The paper considers a thermodynamic efficiency and peculiar features pertaining to realization of heat-recovery steam-gas plant schemes with steam reheating. Possible reserves of higher efficiency concerning plant economy and methods for achieving these goals are given in the paper. The author has made calculations for steam-gas plants of one-, two- and three-loop cycle of steam pressure. An analysis of the obtained results in respect of technical and economic indices and expediency of the application of corresponding plants in power engineering of the Republic of Belarus are presented in the paper.

  12. Steam-Reheat Option for Supercritical-Water-Cooled Reactors

    Science.gov (United States)

    Saltanov, Eugene

    SuperCritical-Water-cooled Reactors (SCWRs) are being developed as one of the Generation-IV nuclear-reactor concepts. Main objectives of the development are to increase thermal efficiency of a Nuclear Power Plant (NPP) and to decrease capital and operational costs. The first objective can be achieved by introducing nuclear steam reheat inside a reactor and utilizing regenerative feedwater heaters. The second objective can be achieved by designing a steam cycle that closely matches that of the mature supercritical fossil-fuelled power plants. The feasibility of these objectives is discussed. As a part of this discussion, heat-transfer calculations have been performed and analyzed for SuperCritical-Water (SCW) and SuperHeated-Steam (SHS) channels of the proposed reactor concept. In the calculations a uniform and three non-uniform Axial Heat Flux Profiles (AHFPs) were considered for six different fuels (UO2, ThO 2, MOX, UC2, UC, and UN) and at average and maximum channel power. Bulk-fluid, sheath, and fuel centerline temperatures as well as the Heat Transfer Coefficient (HTC) profiles were obtained along the fuel-channel length. The HTC values are within a range of 4.7--20 kW/m2·K and 9.7--10 kW/m2·K for the SCW and SHS channels respectively. The main conclusion is that while all the mentioned fuels may be used for the SHS channel, only UC2, UC, or UN are suitable for a SCW channel, because their fuel centerline temperatures are at least 1000°C below melting point, while that of UO2, ThO2 , and MOX may reach melting point.

  13. Modulated reheating and large non-gaussianity in string cosmology

    Energy Technology Data Exchange (ETDEWEB)

    Cicoli, M.; Quevedo, F. [Abdus Salam ICTP, Strada Costiera 11, Trieste 34014 (Italy); Tasinato, G. [Institute of Cosmology and Gravitation, University of Portsmouth, Dennis Sciama Building, Portsmouth, PO1 3FX (United Kingdom); Zavala, I. [Centre for Theoretical Physics, University of Groningen, Nijenborgh 4, 9747 AG Groningen (Netherlands); Burgess, C.P., E-mail: michele.cicoli@desy.de, E-mail: gianmassimo.tasinato@port.ac.uk, E-mail: e.i.zavala@rug.nl, E-mail: cburgess@perimeterinstitute.ca, E-mail: F.Quevedo@damtp.cam.ac.uk [Department of Physics and Astronomy, McMaster University, Hamilton ON (Canada)

    2012-05-01

    A generic feature of the known string inflationary models is that the same physics that makes the inflaton lighter than the Hubble scale during inflation often also makes other scalars this light. These scalars can acquire isocurvature fluctuations during inflation, and given that their VEVs determine the mass spectrum and the coupling constants of the effective low-energy field theory, these fluctuations give rise to couplings and masses that are modulated from one Hubble patch to another. These seem just what is required to obtain primordial adiabatic fluctuations through conversion into density perturbations through the 'modulation mechanism', wherein reheating takes place with different efficiency in different regions of our Universe. Fluctuations generated in this way can generically produce non-gaussianity larger than obtained in single-field slow-roll inflation; potentially observable in the near future. We provide here the first explicit example of the modulation mechanism at work in string cosmology, within the framework of LARGE Volume Type-IIB string flux compactifications. The inflationary dynamics involves two light Kähler moduli: a fibre divisor plays the rôle of the inflaton whose decay rate to visible sector degrees of freedom is modulated by the primordial fluctuations of a blow-up mode (which is made light by the use of poly-instanton corrections). We find the challenges of embedding the mechanism into a concrete UV completion constrains the properties of the non-gaussianity that is found, since for generic values of the underlying parameters, the model predicts a local bi-spectrum with f{sub NL} of order 'a few'. However, a moderate tuning of the parameters gives also rise to explicit examples with f{sub NL} ∼ O(20) potentially observable by the Planck satellite.

  14. CMB constraints on the inflaton couplings and reheating temperature in α-attractor inflation

    Science.gov (United States)

    Drewes, Marco; Kang, Jin U.; Mun, Ui Ri

    2017-11-01

    We study reheating in α-attractor models of inflation in which the inflaton couples to other scalars or fermions. We show that the parameter space contains viable regions in which the inflaton couplings to radiation can be determined from the properties of CMB temperature fluctuations, in particular the spectral index. This may be the only way to measure these fundamental microphysical parameters, which shaped the universe by setting the initial temperature of the hot big bang and contain important information about the embedding of a given model of inflation into a more fundamental theory of physics. The method can be applied to other models of single field inflation.

  15. Nonlinear pulse propagation in a single-and a few-cycle regimes ...

    Indian Academy of Sciences (India)

    The propagation equation for a single- and a few-cycle pulses was derived in a cubic nonlinear medium including the Raman response. Using this equation, the propagation characteristics of a single- and a 4-cycle pulse, at 0.8 m wavelength, were studied numerically in one spatial dimension. It was shown that Raman ...

  16. Dual Pressure versus Hybrid Recuperation in an Integrated Solid Oxide Fuel Cell Cycle – Steam Cycle

    DEFF Research Database (Denmark)

    Rokni, Masoud

    2014-01-01

    A SOFC (solid oxide fuel cell) cycle running on natural gas was integrated with a ST (steam turbine) cycle. The fuel is desulfurized and pre-reformed before entering the SOFC. A burner was used to combust the remaining fuel after the SOFC stacks. The off-gases from the burner were used to produce...... steam in a HRSG (heat recovery steam generator). The bottoming steam cycle was modeled with two configurations: (1) a simple single pressure level and (2) a dual pressure level with both a reheat and a pre-heater. The SOFC stacks in the present SOFC-ST hybrid cycles were not pressurized. The dual...... pressure configuration steam cycle combined with SOFC cycle (SOFC-ST) was new and has not been studied previously. In each of the configuration, a hybrid recuperator was used to recovery the remaining energy of the off-gases after the HRSG. Thus, four different plants system setups were compared to each...

  17. IMPROVEMENT OF SLAB REHEATING PROCESS AT USIMINAS THROUGH MATHEMATICAL SIMULATION

    Directory of Open Access Journals (Sweden)

    Antônio Adel dos Santos

    2012-09-01

    Full Text Available Basic characteristics and application examples of the mathematical simulator for reheating process in walking-beam type furnaces, that has been developed and applied to Usiminas plate mill line at Ipatinga, are shown in this paper. This is a bi-dimensional mathematical model solved by the finite volume method, validated by temperature measurements inside the slab during heating and coded as a visual tool. Among these applications, the following can be highlighted: (i determination of suitable furnace zone temperatures and residence times for processing steels by accelerated cooling technology; (ii determination of slab average temperature at discharging as well as at each zone exit, supplying data to be fed to the automation system at the comissioning stage; (iii analyses of slab thermal distribution through the reheating process, enabling operational optimization

  18. Development of Next Generation Heating System for Scale Free Steel Reheating

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Arvind C. Thekdi

    2011-01-27

    The work carried out under this project includes development and design of components, controls, and economic modeling tools that would enable the steel industry to reduce energy intensity through reduction of scale formation during the steel reheating process. Application of scale free reheating offers savings in energy used for production of steel that is lost as scale, and increase in product yield for the global steel industry. The technology can be applied to a new furnace application as well as retrofit design for conversion of existing steel reheating furnaces. The development work has resulted in the knowledge base that will enable the steel industry and steel forging industry us to reheat steel with 75% to 95% reduction in scale formation and associated energy savings during the reheating process. Scale reduction also results in additional energy savings associated with higher yield from reheat furnaces. Energy used for steel production ranges from 9 MM Btu/ton to 16.6 MM Btu/ton or the industry average of approximately 13 MM Btu/ton. Hence, reduction in scale at reheating stage would represent a substantial energy reduction for the steel industry. Potential energy savings for the US steel industry could be in excess of 25 Trillion Btu/year when the technology is applied to all reheating processes. The development work has resulted in new design of reheating process and the required burners and control systems that would allow use of this technology for steel reheating in steel as well as steel forging industries.

  19. Efficiency of single-family houses and harmonisation of their life cycle participants’ interests

    Directory of Open Access Journals (Sweden)

    Nerija Kvederyte

    2000-01-01

    Full Text Available An efficient single-family house is the main purpose of the life cycle. It determines the necessity to evaluate various decisions of the life cycle of single-family houses and possibilities to satisfy objectives and requirements of the participants of that process. To design and achieve an effective process of the life cycle of a single-family house, it is necessary to take care of its efficiency starting from the determination of needs and objectives and ending with the usage of a building.

  20. Development of a Hemispherical Metal Diaphragm for Single-Cycle Liquid-Metal Positive Expulsion Systems

    National Research Council Canada - National Science Library

    Gorland, Sol

    1965-01-01

    This report presents experimental results pertaining to the design and development of a metallic expulsion diaphragm for single-cycle positive expulsion of high-temperature liquid in an agravity condition...

  1. Analysis of changes in paper cutting forces during the cutting cycle in single-knife guillotine

    OpenAIRE

    Rusin, Agnieszka; Petriaszwili, Georgij

    2013-01-01

    Paper presents the results of changes in the three components of cutting forces of paper stacks cutting during the cutting cycle in single-knife guillotine. The changes of the three components of cutting force at different stages of cutting cycle were analyzed.

  2. Effect of inter-critically reheating temperature on microstructure and properties of simulated inter-critically reheated coarse grained heat affected zone in X70 steel

    International Nuclear Information System (INIS)

    Zhu, Zhixiong; Kuzmikova, Lenka; Li, Huijun; Barbaro, Frank

    2014-01-01

    This study investigated the influence of the inter-critical reheating temperature on the microstructure and mechanical properties of a coarse grained heat affected zone (CGHAZ) in an API 5L grade X70 pipeline steel seam weld. A Gleeble 3500 thermo-mechanical simulator was employed to duplicate particular weld thermal cycles in order to accurately assess specific regions of the weld HAZ. Detailed microstructural analysis, including investigation of the martensite–austenite (M–A) constituent, was performed using optical microscope (OM), scanning electron microscope (SEM) and selective etching techniques. It is shown that the fracture toughness of the CGHAZ is significantly reduced following exposure to a subsequent inter-critical thermal cycle. Fracture toughness gradually improves as the inter-critical temperature is increased, but does not return to the value of the original CGHAZ due to the presence of isolated large M–A particles and coarse microstructure. Significance of M–A particles to the HAZ fracture toughness is first related to the location of particles along prior austenite grain boundaries, followed by the size of individual M–A particles

  3. Reheating temperature and gauge mediation models of supersymmetry breaking

    International Nuclear Information System (INIS)

    Olechowski, Marek; Pokorski, Stefan; Turzynski, Krzysztof; Wells, James D.

    2009-01-01

    For supersymmetric theories with gravitino dark matter, the maximal reheating temperature consistent with big bang nucleosynthesis bounds arises when the physical gaugino masses are degenerate. We consider the cases of a stau or sneutrino next-to-lightest superpartner, which have relatively less constraint from big bang nucleosynthesis. The resulting parameter space is consistent with leptogenesis requirements, and can be reached in generalized gauge mediation models. Such models illustrate a class of theories that overcome the well-known tension between big bang nucleosynthesis and leptogenesis.

  4. Non-conformal evolution of magnetic fields during reheating

    International Nuclear Information System (INIS)

    Calzetta, Esteban; Kandus, Alejandra

    2015-01-01

    We consider the evolution of electromagnetic fields coupled to conduction currents during the reheating era after inflation, and prior to the establishing of the proton-electron plasma. We assume that the currents may be described by second order causal hydrodynamics. The resulting theory is not conformally invariant. The expansion of the Universe produces temperature gradients which couple to the current and generally oppose Ohmic dissipation. Although the effect is not strong, it suggests that the unfolding of hydrodynamic instabilities in these models may follow a different pattern than in first order theories, and even than in second order theories on non expanding backgrounds

  5. A nonequilibrium renormalization group approach to turbulent reheating

    International Nuclear Information System (INIS)

    Zanella, Juan; Calzetta, Esteban

    2007-01-01

    We use nonequilibrium renormalization group (RG) techniques to analyse the thermalization process in quantum field theory, and, by extension, reheating after inflation. Even if at a high scale Λ the theory is described by a non-dissipative λψ 4 theory, and the RG running induces nontrivial noise and dissipation. For long wavelength and slowly varying field configurations, the noise and dissipation are white and ohmic, respectively. The theory will then tend to thermalize to an effective temperature given by the fluctuation-dissipation theorem

  6. Non-conformal evolution of magnetic fields during reheating

    Energy Technology Data Exchange (ETDEWEB)

    Calzetta, Esteban [Departamento de Física and IFIBA, FCEyN—Universidad de Buenos Aires, Ciudad Universitaria, CABA (Argentina); Kandus, Alejandra, E-mail: calzetta@df.uba.ar, E-mail: kandus@uesc.br [LATO, DCET—Universidade Estadual de Santa Cruz, Rodovia Ilhéus-Itabuna km 16 s/n, Ilhéus, BA (Brazil)

    2015-03-01

    We consider the evolution of electromagnetic fields coupled to conduction currents during the reheating era after inflation, and prior to the establishing of the proton-electron plasma. We assume that the currents may be described by second order causal hydrodynamics. The resulting theory is not conformally invariant. The expansion of the Universe produces temperature gradients which couple to the current and generally oppose Ohmic dissipation. Although the effect is not strong, it suggests that the unfolding of hydrodynamic instabilities in these models may follow a different pattern than in first order theories, and even than in second order theories on non expanding backgrounds.

  7. Inflation and reheating in induced-gravity models

    International Nuclear Information System (INIS)

    Barr, S.; Segre, G.

    1990-01-01

    The Planck mass is generated dynamically in induced-gravity models, typically being related to the vacuum expectation value of a scalar field φ, ε 1/2 left-angle φ right-angle=M Pl / √8π , where ε is a dimensionless parameter, typically smaller than one. We discuss in this paper the decay of the φ particle, which is mainly into gravitons, and the consequences this has for models in which the φ field is responsible for inflation. We show in particular that too much energy is stored in φ oscillations and adequate reheating does not occur

  8. Investigation on the crystallography of the transformation products of reverted austenite in intercritically reheated coarse grained heat affected zone

    International Nuclear Information System (INIS)

    You, Yang; Shang, Chengjia; Chen, Liang; Subramanian, Sundaresa

    2013-01-01

    Highlights: ► Area of reverted austenite is traced out by crystallographic information. ► Bainite and martensite regions were confirmed within it. ► The martensite region is considered as the blocky MA particles. ► Martensite region has high deformation to initiate fracture. ► More uniform transformation of the reverted austenite is good for toughness. -- Abstract: In present study the intercritically reheated coarse grained heat affected zone (ICCGHAZ) showing the worst impact toughness in the heat affected zone of multi-pass welding was simulated by Gleeble-1500, and its microstructure was investigated in detail by means of scanning electron microscope (SEM) and electron backscattering diffraction (EBSD). With the crystallographic information from EBSD scanning the area of a single reverted austenite grain which formed during the thermal cycles of second pass simulation was traced out. Within it two regions with different characteristic both in morphology and crystallography were found out, showing an un-uniform transformation of the reverted austenite. The region I is a bainitic region containing larger bainitic ferrite grains, while the region II is made up of several clusters containing tiny grains. Based on the crystallographic information each cluster was determined as martensite island thereby should be considered as blocky Martensite/Austenite constituent (M/A), which is hard phase and harmful for toughness. Analysis on the level of deformation shows that the region II is much higher deformed than the region I, indicating there is high stress concentration within the region II. The possible influence of the region I and the region II on fracture is discussed under the early proposed M/A’s fracture-initiating mechanisms. It suggests that the main cause of the toughness reduction is the un-uniform transformation of the reverted austenite, and the toughness performance of the ICCGHAZ could be improved if the transformation of the reverted

  9. Thermodynamic Analysis of a Steam Power Plant with Double Reheat and Feed Water Heaters

    Directory of Open Access Journals (Sweden)

    M. M. Rashidi

    2014-03-01

    Full Text Available A steam cycle with double reheat and turbine extraction is presented. Six heaters are used, three of them at high pressure and the other three at low pressure with deaerator. The first and second law analysis for the cycle and optimization of the thermal and exergy efficiencies are investigated. An exergy analysis is performed to guide the thermodynamic improvement for this cycle. The exergy and irreversibility analyses of each component of the cycle are determined. Effects of turbine inlet pressure, boiler exit steam temperature, and condenser pressure on the first and second laws' efficiencies are investigated. Also the best turbine extraction pressure on the first law efficiency is obtained. The results show that the biggest exergy loss occurs in the boiler followed by the turbine. The results also show that the overall thermal efficiency and the second law efficiency decrease as the condenser pressure increases for any fixed outlet boiler temperature, however, they increase as the boiler temperature increases for any condenser pressure. Furthermore, the best values of extraction pressure from high, intermediate, and low pressure turbine which give the maximum first law efficiencies are obtained based on the required heat load corresponding to each exit boiler temperature.

  10. Simulation and parametric optimisation of thermal power plant cycles

    Directory of Open Access Journals (Sweden)

    P. Ravindra Kumar

    2016-09-01

    Full Text Available The objective of the paper is to analyse parametric studies and optimum steam extraction pressures of three different (subcritical, supercritical and ultra-supercritical coal fired power plant cycles at a particular main steam temperature of 600 °C by keeping the reheat temperature at 537 °C and condenser pressure at 0.09 bar as constant. In order to maximize the heat rate gain possible with supercritical and ultra-supercritical steam conditions, eight stages of feed water heater arrangement with single reheater is considered. The system is optimized in such a way that the percentage exergetic losses are reduced for the increase of the exergetic efficiency and higher fuel utilization. The plant cycles are simulated and optimized by using Cycle Tempo 5.0 simulation software tool. From the simulation study, it is observed that the thermal efficiency of the three different power plant cycles obtained as 41.40, 42.48 and 43.03%, respectively. The specific coal consumption for three different power plant cycles are 0.56, 0.55 and 0.54 Tonnes/MWh. The improvement in feed water temperatures at the inlet of steam generator of respective cycles are 291, 305 and 316 °C.

  11. Condensation front modelling in a moisture separator reheater by application of SICLE numerical model

    International Nuclear Information System (INIS)

    Grange, J.L.; Caremoli, C.; Eddi, M.

    1988-01-01

    This paper presents improvements performed on SICLE numerical model in order to analyse the condensation front that occurs in the moisture separator reheaters (MSR) of nuclear power plants. Modifications of SICLE numerical model architecture and a fine modelling of reheater have allowed to correctly simulate the MSR thermohydraulic behaviour during a severe transient (plant islanding) [fr

  12. 49 CFR 180.211 - Repair, rebuilding and reheat treatment of DOT-4 series specification cylinders.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Repair, rebuilding and reheat treatment of DOT-4... Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS... Use of Cylinders § 180.211 Repair, rebuilding and reheat treatment of DOT-4 series specification...

  13. Second Law Of Thermodynamics Analysis Of Triple Cycle Power Plant

    Directory of Open Access Journals (Sweden)

    Matheus M. Dwinanto

    2012-11-01

    Full Text Available Triple cycle power plant with methane as a fuel has been analyzed on the basis of second law of thermodynamics.In this model, ideal Brayton cycle is selected as a topping cycle as it gives higher efficiency at lower pressure ratio comparedintercooler and reheat cycle. In trilple cycle the bottoming cycles are steam Rankine and organic Rankine cycle. Ammoniahas suitable working properties like critical temperature, boiling temperature, etc. Steam cycle consists of a deaerator andreheater. The bottoming ammonia cycle is a ideal Rankine cycle. Single pressure heat recovery steam and ammoniagenerators are selected for simplification of the analysis. The effects of pressure ratio and maximum temperature which aretaken as important parameters regarding the triple cycle are discussed on performance and exergetic losses. On the otherhand, the efficiency of the triple cycle can be raised, especially in the application of recovering low enthalpy content wasteheat. Therefore, by properly combining with a steam Rankine cycle, the ammonia Rankine cycle is expected to efficientlyutilize residual yet available energy to an optimal extent. The arrangement of multiple cycles is compared with combinedcycle having the same sink conditions. The parallel type of arrangement of bottoming cycle is selected due to increasedperformance.

  14. Gravitational wave signals and cosmological consequences of gravitational reheating

    Science.gov (United States)

    Artymowski, Michał; Czerwińska, Olga; Lalak, Zygmunt; Lewicki, Marek

    2018-04-01

    Reheating after inflation can proceed even if the inflaton couples to Standard Model (SM) particles only gravitationally. However, particle production during the transition between de-Sitter expansion and a decelerating Universe is rather inefficient and the necessity to recover the visible Universe leads to a non-standard cosmological evolution initially dominated by remnants of the inflaton field. We remain agnostic to the specific dynamics of the inflaton field and discuss a generic scenario in which its remnants behave as a perfect fluid with a general barotropic parameter w. Using CMB and BBN constraints we derive the allowed range of inflationary scales. We also show that this scenario results in a characteristic primordial Gravitational Wave (GW) spectrum which gives hope for observation in upcoming runs of LIGO as well as in other planned experiments.

  15. Microstructural characteristics and gastro-small intestinal digestion in vitro of potato starch: Effects of refrigerated storage and reheating in microwave.

    Science.gov (United States)

    Colussi, Rosana; Singh, Jaspreet; Kaur, Lovedeep; Zavareze, Elessandra da Rosa; Dias, Alvaro Renato Guerra; Stewart, Robert B; Singh, Harjinder

    2017-07-01

    The objective of our study was to evaluate paste clarity, retrogradation (syneresis %), thermal characteristics and kinetics of glucose release during in vitro gastro-small intestinal digestion of freshly cooked and refrigerated potato starch. Freshly cooked starch pastes had a paste clarity of 71%, which decreased to 35.4% whereas syneresis (%) increased after 7days of refrigerated storage. The X-ray and thermal characteristics of native, retrograded and microwave reheated starch samples differed significantly from each other. For the freshly cooked starch pastes, ∼88% starch hydrolysis was observed at the end (150min) of digestion under simulated gastro-small intestinal conditions that decreased to ∼70% for the 7day stored pastes. The hydrolysis (%) of refrigerated pastes increased to 86% and 92% after one and two cycles of microwave reheating, respectively. These results contribute to the understanding of starch retrogradation in relation to starch digestion. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Latent Membrane Protein 1 as a molecular adjuvant for single-cycle lentiviral vaccines

    Directory of Open Access Journals (Sweden)

    Rahmberg Andrew R

    2011-05-01

    Full Text Available Abstract Background Molecular adjuvants are a promising method to enhance virus-specific immune responses and protect against HIV-1 infection. Immune activation by ligands for receptors such as CD40 can induce dendritic cell activation and maturation. Here we explore the incorporation of two CD40 mimics, Epstein Barr Virus gene LMP1 or an LMP1-CD40 chimera, into a strain of SIV that was engineered to be limited to a single cycle of infection. Results Full length LMP1 or the chimeric protein LMP1-CD40 was cloned into the nef-locus of single-cycle SIV. Human and Macaque monocyte derived macrophages and DC were infected with these viruses. Infected cells were analyzed for activation surface markers by flow cytometry. Cells were also analyzed for secretion of pro-inflammatory cytokines IL-1β, IL-6, IL-8, IL-12p70 and TNF by cytometric bead array. Conclusions Overall, single-cycle SIV expressing LMP1 and LMP1-CD40 produced a broad and potent TH1-biased immune response in human as well as rhesus macaque macrophages and DC when compared with control virus. Single-cycle SIV-LMP1 also enhanced antigen presentation by lentiviral vector vaccines, suggesting that LMP1-mediated immune activation may enhance lentiviral vector vaccines against HIV-1.

  17. Self-phase modulation of a single-cycle THz pulse

    DEFF Research Database (Denmark)

    Turchinovich, Dmitry; Hvam, Jørn Märcher; Hoffmann, M. C.

    2013-01-01

    We demonstrate self-phase modulation (SPM) of a single-cycle THz pulse in a semiconductor, using bulk n-GaAs as a model system. The SPM arises from the heating of free electrons in the electric field of the THz pulse. Electron heating leads to an ultrafast reduction of the plasma frequency, which...

  18. Redox cycling performance of inert-substrate-supported tubular single cells with nickel anode current collector

    Science.gov (United States)

    Zhao, Kai; Kim, Bok-Hee; Xu, Qing; Du, Yanhai; Ahn, Byung-Guk

    2015-10-01

    An inert-substrate-supported tubular single cell, with a configuration of porous yttria-stabilized zirconia (YSZ) supporter/Ni anode current collector/Ni-Ce0.8Sm0.2O1.9 anode/YSZ/Ce0.8Sm0.2O1.9 bi-layer electrolyte/La0.6Sr0.4Co0.2Fe0.8O3-δ cathode, has been fabricated by extrusion and dip-coating techniques. Thickness of the Ni layer is modified by controlling the number of dip-coatings from one to four. Electrochemical performance and redox cycling stability of the single cell are investigated with respect to the microstructure of the Ni layer. Increasing the thickness of the Ni layer enhances the maximum power density of the cell, while it is unfavorable for the redox cycling stability. Considering the trade-off between these two aspects, an optimum dip-coating time is determined to be two. The cell shows a reasonable maximum power density of 453 mW cm-2 at 800 °C, as well as good redox cycling stability within eight redox cycles. Additionally, 10 vol.% Ce0.8Sm0.2O1.9 ceramic particle is incorporated into the Ni layer to further improve the redox cycling stability. The cell exhibits enhanced redox cycling performance after the Ce0.8Sm0.2O1.9 incorporation. Within seven redox cycles, the cell voltage loss is less than 1% at a current density of 400 mA cm-2, and it maintains 93% of its initial performance after 11 redox cycles.

  19. Standard test method for determination of "microwave safe for reheating" for ceramicware

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2006-01-01

    1.1 This test method determines the suitability of ceramicware for use in microwave re-heating applications. Microwave ovens are mainly used for reheating and defrosting frozen foods. Severe thermal conditions can occur while reheating foods. Typical reheating of foods requires one to five min. in the microwave at the highest power settings. Longer periods than five minutes are considered cooking. Cooking test methods and standards are not addressed in this test method. Most ceramicware is minimally absorbing of the microwave energy and will not heat up significantly. Unfortunately there are some products that absorb microwave energy to a greater extent and can become very hot in the microwave and pose a serious hazard. Additionally, the nature of microwave heating introduces radiation in a non-uniform manner producing temperature differentials in the food being cooked as well as the ceramic container holding it. The differential may become great enough to thermal shock the ware and create dangerous condition...

  20. Pressure at the ISM-halo interface: A reheating frequency dependence

    Directory of Open Access Journals (Sweden)

    Ćirković M.M.

    1998-01-01

    Full Text Available The dependence of the thermal pressure of hot galactic halos on a model parameter describing the frequency of major reheating episodes during galactic history is investigated. Pressure on the interface between interstellar medium and the halo gas is especially interesting, since empirical evidence here offers one of the simplest constraints on halo models. It is shown that two-phase model of Mo & Miralda-Escudé is sufficiently robust with respect to uncertainties in the average interval between reheating.

  1. Gravitational leptogenesis, reheating, and models of neutrino mass

    Science.gov (United States)

    Adshead, Peter; Long, Andrew J.; Sfakianakis, Evangelos I.

    2018-02-01

    Gravitational leptogenesis refers to a class of baryogenesis models in which the matter-antimatter asymmetry of the Universe arises through the standard model lepton-number gravitational anomaly. In these models chiral gravitational waves source a lepton asymmetry in standard model neutrinos during the inflationary epoch. We point out that gravitational leptogenesis can be successful in either the Dirac or Majorana neutrino mass scenario. In the Dirac mass scenario, gravitational leptogenesis predicts a relic abundance of sterile neutrinos that remain out of equilibrium, and the lepton asymmetry carried by the standard model sector is unchanged. In the Majorana mass scenario, the neutrinos participate in lepton-number-violating interactions that threaten to wash out the lepton asymmetry during postinflationary reheating. However, we show that a complete (exponential) washout of the lepton asymmetry is prevented if the lepton-number-violating interactions go out of equilibrium before all of the standard model Yukawa interactions come into equilibrium. The baryon and lepton asymmetries carried by right-chiral quarks and leptons are sequestered from the lepton-number violation, and the washout processes only suppress the predicted baryon asymmetry by a factor of ɛw .o .=±O (0.1 ). The sign of ɛw .o . depends on the model parameters in such a way that a future measurement of the primordial gravitational wave chirality would constrain the scale of lepton-number violation (heavy Majorana neutrino mass).

  2. Self-consistent estimates of magnetic fields from reheating

    International Nuclear Information System (INIS)

    Calzetta, Esteban; Kandus, Alejandra

    2002-01-01

    We investigate the generation of primordial magnetic fields from stochastic currents created by the cosmological transition from inflation to reheating. We consider N charged scalar fields coupled to the electromagnetic field in a curved background and derive self-consistent equations for the evolution of the two point functions of the fields, which in the large-N limit give a decoupled set for the scalar and the electromagnetic functions. The main contribution to the electric current comes from the infrared portion of the spectrum of created particles, and in this limit the damping of the magnetic field is not due to normal conductivity but to London currents in the scalar field. For a given set of the physical parameters of the problem, we solved this equation numerically and found that, due to the fact that the London currents are oscillating, the field actually grows exponentially during the time interval in which our large-N limit equations are valid. Although for the chosen parameters the induced field is weak, the present uncertainties on their actual values leave open the possibility for higher intensities

  3. Nonlinear pulse propagation in a single- and a few-cycle regimes ...

    Indian Academy of Sciences (India)

    In this work, we study the effect of the delayed nonlinear response (intrapulse. Raman effect) on the propagation characteristics of a single- and a few-cycle pulse at 0.8 µm wavelength in a silica glass ..... 0.03923 fs2/µm, Tr = 3 fs and σ = 0.7. effect leads to a frequency shift toward higher frequencies, in the trailing edge and.

  4. Robust synchronization of coupled circadian and cell cycle oscillators in single mammalian cells

    Science.gov (United States)

    Bieler, Jonathan; Cannavo, Rosamaria; Gustafson, Kyle; Gobet, Cedric; Gatfield, David; Naef, Felix

    2014-01-01

    Circadian cycles and cell cycles are two fundamental periodic processes with a period in the range of 1 day. Consequently, coupling between such cycles can lead to synchronization. Here, we estimated the mutual interactions between the two oscillators by time-lapse imaging of single mammalian NIH3T3 fibroblasts during several days. The analysis of thousands of circadian cycles in dividing cells clearly indicated that both oscillators tick in a 1:1 mode-locked state, with cell divisions occurring tightly 5 h before the peak in circadian Rev-Erbα-YFP reporter expression. In principle, such synchrony may be caused by either unidirectional or bidirectional coupling. While gating of cell division by the circadian cycle has been most studied, our data combined with stochastic modeling unambiguously show that the reverse coupling is predominant in NIH3T3 cells. Moreover, temperature, genetic, and pharmacological perturbations showed that the two interacting cellular oscillators adopt a synchronized state that is highly robust over a wide range of parameters. These findings have implications for circadian function in proliferative tissues, including epidermis, immune cells, and cancer. PMID:25028488

  5. Active and Inactive Leg Hemodynamics during Sequential Single-Leg Interval Cycling.

    Science.gov (United States)

    Gordon, Nicole; Abbiss, Chris R; Ihsan, Mohammed; Maiorana, Andrew J; Peiffer, Jeremiah J

    2018-01-11

    Leg order during sequential single-leg cycling (i.e. exercising both legs independently within a single session) may affect local muscular responses potentially influencing adaptations. This study examined the cardiovascular and skeletal muscle hemodynamic responses during double-leg and sequential single-leg cycling. Ten young healthy adults (28 ± 6 y) completed six 1-min double-leg intervals interspersed with one minute of passive recovery and, on a separate occasion, 12 (six with one leg followed by six with the other leg) 1-min single-leg intervals interspersed with one minute of passive recovery. Oxygen consumption, heart rate, blood pressure, muscle oxygenation, muscle blood volume and power output were measured throughout each session. Oxygen consumption, heart rate and power output were not different between sets of single-leg intervals but the average of both sets was lower than the double-leg intervals. Mean arterial pressure was higher during double-leg compared with sequential single-leg intervals (115 ± 9 mmHg vs. 104 ± 9 mmHg; p<0.05) and higher during the initial compared with second set of single-leg intervals (108 ± 10 mmHg vs. 101 ± 10 mmHg; p<0.05). The increase in muscle blood volume from baseline was similar between the active single-leg and double-leg (267 ± 150 μM[BULLET OPERATOR]cm vs. 214 ± 169 μM[BULLET OPERATOR]cm; p=0.26). The pattern of change in muscle blood volume from the initial to second set of intervals was significantly different (p<0.05) when the leg was active in the initial (-52.3 ± 111.6%) compared with second set (65.1 ± 152.9%). These data indicate that the order in which each leg performs sequential single-leg cycling influences the local hemodynamic responses, with the inactive muscle influencing the stimulus experienced by the contralateral leg.

  6. Thermodynamic analysis of single-stage and multi-stage adsorption refrigeration cycles with activated carbon–ammonia working pair

    International Nuclear Information System (INIS)

    Xu, S.Z.; Wang, L.W.; Wang, R.Z.

    2016-01-01

    Highlights: • Activated carbon–ammonia multi-stage adsorption refrigerator was analyzed. • COP, exergetic efficiency and entropy production of cycles were calculated. • Single-stage cycle usually has the advantages of simple structure and high COP. • Multi-stage cycles adapt to critical conditions better than single-stage cycle. • Boundary conditions for choosing optimal cycle were summarized as tables. - Abstract: Activated carbon–ammonia multi-stage adsorption refrigeration cycle was analyzed in this article, which realized deep-freezing for evaporating temperature under −18 °C with heating source temperature much lower than 100 °C. Cycle mathematical models for single, two and three-stage cycles were established on the basis of thorough thermodynamic analysis. According to simulation results of thermodynamic evaluation indicators such as COP (coefficient of performance), exergetic efficiency and cycle entropy production, multi-stage cycle adapts to high condensing temperature, low evaporating temperature and low heating source temperature well. Proposed cycle with selected working pair can theoretically work under very severe conditions, such as −25 °C evaporating temperature, 40 °C condensing temperature, and 70 °C heating source temperature, but under these working conditions it has the drawback of low cycle adsorption quantity. It was found that both COP and exergetic efficiency are of great reference value in the choice of cycle, whereas entropy production is not so useful for cycle stage selection. Finally, the application boundary conditions of single-stage, two-stage, and three-stage cycles were summarized as tables according to the simulation results, which provides reference for choosing optimal cycle under different conditions.

  7. Single-cell paired-end genome sequencing reveals structural variation per cell cycle

    Science.gov (United States)

    Voet, Thierry; Kumar, Parveen; Van Loo, Peter; Cooke, Susanna L.; Marshall, John; Lin, Meng-Lay; Zamani Esteki, Masoud; Van der Aa, Niels; Mateiu, Ligia; McBride, David J.; Bignell, Graham R.; McLaren, Stuart; Teague, Jon; Butler, Adam; Raine, Keiran; Stebbings, Lucy A.; Quail, Michael A.; D’Hooghe, Thomas; Moreau, Yves; Futreal, P. Andrew; Stratton, Michael R.; Vermeesch, Joris R.; Campbell, Peter J.

    2013-01-01

    The nature and pace of genome mutation is largely unknown. Because standard methods sequence DNA from populations of cells, the genetic composition of individual cells is lost, de novo mutations in cells are concealed within the bulk signal and per cell cycle mutation rates and mechanisms remain elusive. Although single-cell genome analyses could resolve these problems, such analyses are error-prone because of whole-genome amplification (WGA) artefacts and are limited in the types of DNA mutation that can be discerned. We developed methods for paired-end sequence analysis of single-cell WGA products that enable (i) detecting multiple classes of DNA mutation, (ii) distinguishing DNA copy number changes from allelic WGA-amplification artefacts by the discovery of matching aberrantly mapping read pairs among the surfeit of paired-end WGA and mapping artefacts and (iii) delineating the break points and architecture of structural variants. By applying the methods, we capture DNA copy number changes acquired over one cell cycle in breast cancer cells and in blastomeres derived from a human zygote after in vitro fertilization. Furthermore, we were able to discover and fine-map a heritable inter-chromosomal rearrangement t(1;16)(p36;p12) by sequencing a single blastomere. The methods will expedite applications in basic genome research and provide a stepping stone to novel approaches for clinical genetic diagnosis. PMID:23630320

  8. A study of the phase transition of reheated diphenyl carbazide (DPC) by using UV spectroscopy.

    Science.gov (United States)

    El-Kabbany, F; Taha, S; Hafez, M

    2014-07-15

    Phase transition phenomenon in reheated diphenyl carbazide (DPC) is studied here using UV spectroscopy. The optical band gap for reheated DPC is obtained by measuring the optical diffused reflectance (DR) and equals to 3.55 eV. Also, the optical band gap is calculated using UV technique and equals to 3.548 eV. The absorbance of reheated DPC is studied at some selected temperatures in order to check the presence of phase transitions at 90°C and 125°C. According to the present work, the band gaps are calculated at 80°C, 110°C and 130°C and equal to 3.548 eV. But at 100°C, the optical band gap has changed to 4.139 eV. It was found that each phase of reheated DPC belongs to a certain definite crystal structure. The presence of the phase transitions are checked and confirmed by scanning electron microscopy (SEM). The structural properties and morphology of reheated diphenyl carbazide are investigated by SEM. The SEM images are taken at some selected temperatures to confirm the presence of phase transitions. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Reheating mechanism of the curvaton with nonminimal derivative coupling to gravity

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Taotao [Central China Normal University, Institute of Astrophysics, Wuhan (China); Central China Normal University, Key Laboratory of Quark and Lepton Physics (MOE) and College of Physical Science and Technology, Wuhan (China); Feng, Kaixi [Chinese Academy of Sciences, Institute of Theoretical Physics, Beijing (China)

    2017-10-15

    In this paper, we continue our study of the curvaton model with nonminimal derivative coupling (NDC) to Einstein gravity proposed in our previous work (Feng in Phys Lett B 729:99, 2014; Feng and Qiu in Phys Rev D 90(12):123508, 2014), focusing on the reheating mechanism. We found that according to whether the curvaton has or has not dominated the background after the end of inflation, it will have two different behaviors of evolution, which should be the general property of the curvaton with nonminimal couplings. This will cause two different parts of reheating, which goes on via the parametric resonance process. The reheating temperature is estimated for both cases in which reheating completes before and after curvaton domination, and the constraints are quite loose compared to that of overproduction of gravitinos. Finally we investigated the evolution of curvature perturbation during reheating. We have shown both analytically and numerically that the curvature perturbation will not blow up during the resonance process. (orig.)

  10. Mitochondrial specialization revealed by single muscle fiber proteomics: focus on the Krebs cycle.

    Science.gov (United States)

    Schiaffino, S; Reggiani, C; Kostrominova, T Y; Mann, M; Murgia, M

    2015-12-01

    We have developed a highly sensitive mass spectrometry-based proteomic workflow to examine the proteome of single muscle fibers. This study revealed significant differences in the mitochondrial proteome of the four major fiber types present in mouse skeletal muscle. Here, we focus on Krebs cycle enzymes and in particular on the differential distribution of the two mitochondrial isocitrate dehydrogenases, IDH2 and IDH3. Type 1/slow fibers contain high levels of IDH2 and relatively low levels of IDH3, whereas fast 2X and 2B fibers show an opposite expression pattern. The findings suggest that in skeletal muscle, IDH2 functions in the forward direction of the Krebs cycle and that substrate flux along the cycle occurs predominantly via IDH2 in type 1 fibers and via IDH3 in 2X and 2B fibers. IDH2-mediated conversion of isocitrate to α-ketoglutarate leads to the generation of NADPH, which is critical to buffering the H2O2 produced by the respiratory chain. Nicotinamide nucleotide transhydrogenase (NNT), the other major mitochondrial enzyme involved in NADPH generation, is also more abundant in type 1 fibers. We suggest that the continuously active type 1 fibers are endowed with a more efficient H2O2 scavenging capacity to cope with the higher levels of reactive oxygen species production. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Output power analyses for the thermodynamic cycles of thermal power plants

    Science.gov (United States)

    Sun, Chen; Cheng, Xue-Tao; Liang, Xin-Gang

    2014-05-01

    Thermal power plant is one of the important thermodynamic devices, which is very common in all kinds of power generation systems. In this paper, we use a new concept, entransy loss, as well as exergy destruction, to analyze the single reheating Rankine cycle unit and the single stage steam extraction regenerative Rankine cycle unit in power plants. This is the first time that the concept of entransy loss is applied to the analysis of the power plant Rankine cycles with reheating and steam extraction regeneration. In order to obtain the maximum output power, the operating conditions under variant vapor mass flow rates are optimized numerically, as well as the combustion temperatures and the off-design flow rates of the flue gas. The relationship between the output power and the exergy destruction rate and that between the output power and the entransy loss rate are discussed. It is found that both the minimum exergy destruction rate and the maximum entransy loss rate lead to the maximum output power when the combustion temperature and heat capacity flow rate of the flue gas are prescribed. Unlike the minimum exergy destruction rate, the maximum entransy loss rate is related to the maximum output power when the highest temperature and heat capacity flow rate of the flue gas are not prescribed.

  12. Separation of Minor Actinides by a Single Cycle Approach using Unsymmetrical Diglycolamide and Diglycolamic Acid

    International Nuclear Information System (INIS)

    Kumaresan, R.; Nayak, P.K.; Venkatesan, K.A.; Prathibha, T.; Rajeswari, S.; Antony, M.P.; Vasudeva Rao, P.R.

    2015-01-01

    A new class of CHON-extractants, namely unsymmetrical diglycol-amides (UDGA) and diglycolamic acid were developed for the partitioning of minor actinides from high level liquid waste. Group separation of trivalent metal ions (An(III) + Ln(III)) from fast reactor (FR) simulated high-level liquid waste (SHLLW) was demonstrated using UDGA, N,N,-didodecyl-N',N'-dioctyl-3-oxapentane-1,5-diamide (D 3 DODGA)without the addition of organic phase modifier in n-dodecane phase. A single-cycle approach has been explored for the separation of trivalent actinides from FR-SHLLW using the solvent phase composed of D 3 DODGA and di-2-ethylhexyl-diglycolamic acid (HDEHDGA), or tetra-bis(2-ethylhexyl)diglycolamide (TEHDGA) and bis(2-ethylhexyl)phosphoric acid(HDEHP). A procedure was developed to minimise the extraction of unwanted metal ions by using aqueous soluble complexing agents in FR-SHLLW. Based on the optimised conditions, a counter current mixer-settler run was performed to separate Am(III) from FR-SHLLW using a novel ejector based mixer-settler. Quantitative extraction of trivalent (Am(III) + Ln(III)) was observed in both the systems. Am(III) alone was back extracted from loaded organic phase using a solution of diethylenetriaminepentaacetic acid - citric acid. The results showed the possibility of selective separation of trivalent actinides alone from high level liquid waste in a single cycle process. (authors)

  13. Thermal Efficiency of Cogeneration Units with Multi-Stage Reheating for Russian Municipal Heating Systems

    Directory of Open Access Journals (Sweden)

    Evgeny Lisin

    2016-04-01

    Full Text Available This paper explores the layout of an optimum process for supplying heat to Russian municipal heating systems operating in a market environment. We analyze and compare the standard cogeneration unit design with two-stage reheating of service water coming from controlled extraction locations and layouts that employ three in-line reheaters with heat the supply controlled by a rotary diaphragm and qualitative/quantitative methods (so-called “uncontrolled extraction”. Cogeneration unit designs are benchmarked in terms of their thermal efficiency expressed as a fuel consumption rate. The specific fuel consumption rate on electricity production is viewed as a key parameter of thermal efficiency.

  14. Predicting the Size of Sunspot Cycle 24 on the Basis of Single- and Bi-Variate Geomagnetic Precursor Methods

    Science.gov (United States)

    Wilson, Robert M.; Hathaway, David H.

    2009-01-01

    Examined are single- and bi-variate geomagnetic precursors for predicting the maximum amplitude (RM) of a sunspot cycle several years in advance. The best single-variate fit is one based on the average of the ap index 36 mo prior to cycle minimum occurrence (E(Rm)), having a coefficient of correlation (r) equal to 0.97 and a standard error of estimate (se) equal to 9.3. Presuming cycle 24 not to be a statistical outlier and its minimum in March 2008, the fit suggests cycle 24 s RM to be about 69 +/- 20 (the 90% prediction interval). The weighted mean prediction of 11 statistically important single-variate fits is 116 +/- 34. The best bi-variate fit is one based on the maximum and minimum values of the 12-mma of the ap index; i.e., APM# and APm*, where # means the value post-E(RM) for the preceding cycle and * means the value in the vicinity of cycle minimum, having r = 0.98 and se = 8.2. It predicts cycle 24 s RM to be about 92 +/- 27. The weighted mean prediction of 22 statistically important bi-variate fits is 112 32. Thus, cycle 24's RM is expected to lie somewhere within the range of about 82 to 144. Also examined are the late-cycle 23 behaviors of geomagnetic indices and solar wind velocity in comparison to the mean behaviors of cycles 2023 and the geomagnetic indices of cycle 14 (RM = 64.2), the weakest sunspot cycle of the modern era.

  15. Excitation of random intense single-cycle light-pulse chains in optical fiber

    International Nuclear Information System (INIS)

    Ding, Y C; Zhang, F L; Gao, J B; Chen, Z Y; Lin, C Y; Yu, M Y

    2014-01-01

    Excitation of intense periodic single-cycle light pulses in a stochastic background arising from continuous wave stimulated Brillouin scattering (SBS) in a long optical fiber with weak optical feedback is found experimentally and modeled theoretically. Such intense light-pulse chains occur randomly and the optical feedback is a requirement for their excitation. The probability of these forms, among the large number of experimental output signals with identifiable waveforms, appearing is only about 3%, with the remainder exhibiting regular SBS characteristics. It is also found that pulses with low period numbers appear more frequently and the probability distribution for their occurrence in terms of the pulse power is roughly L-shaped, like that for rogue waves. The results from a three-wave-coupling model for SBS including feedback phase control agree well qualitatively with the observed phenomena. (paper)

  16. Low Cycle Fatigue of Single Crystal Nickel-based Superalloy DD6 at 1100℃

    Directory of Open Access Journals (Sweden)

    ZHANG Shichao

    2018-02-01

    Full Text Available The total strain-controlled low cycle fatigue(LCF behaviors of a single crystal superalloy DD6 at 1100℃ for R=-1 and 0.05 were investigated. The results of LCF tests indicated that the cyclic hardening/softening behavior of the alloy not only has the relationship with the microstructure of the material, but also the loading status. The mean stress relaxation occurred under asymmetric straining. The rate of mean stress relaxation increased with the increasing of strain amplitude; when R=-1, the alloy shows tension-compression asymmetry behavior. All the LCF data obtain under various ratios were well correlated by three models for lifetime prediction, the precision rates predicted are fallen into the factor of±2 times scatter band.

  17. Reheating effects in the matter power spectrum and implications for substructure

    International Nuclear Information System (INIS)

    Erickcek, Adrienne L.; Sigurdson, Kris

    2011-01-01

    The thermal and expansion history of the Universe before big bang nucleosynthesis is unknown. We investigate the evolution of cosmological perturbations through the transition from an early matter era to radiation domination. We treat reheating as the perturbative decay of an oscillating scalar field into relativistic plasma and cold dark matter. After reheating, we find that subhorizon perturbations in the decay-produced dark matter density are significantly enhanced, while subhorizon radiation perturbations are instead suppressed. If dark matter originates in the radiation bath after reheating, this suppression may be the primary cutoff in the matter power spectrum. Conversely, for dark matter produced nonthermally from scalar decay, enhanced perturbations can drive structure formation during the cosmic dark ages and dramatically increase the abundance of compact substructures. For low reheat temperatures, we find that as much as 50% of all dark matter is in microhalos with M > or approx. 0.1M + at z≅100, compared to a fraction of ∼10 -10 in the standard case. In this scenario, ultradense substructures may constitute a large fraction of dark matter in galaxies today.

  18. Reheating via Gravitational Particle Production in Simple Models of Quintessence or ΛCDM Inflation

    Directory of Open Access Journals (Sweden)

    Jaume de Haro

    2017-11-01

    Full Text Available We have tested some simple Λ CDM (the same test is also valid for quintessence inflation models, imposing that they match with the recent observational data provided by the BICEP and Planck’s team and leading to a reheating temperature, which is obtained via gravitational particle production after inflation, supporting the nucleosynthesis success.

  19. Irreversible Thermodynamic Description of Dark Matter and Radiation Creation during Inflationary Reheating

    Directory of Open Access Journals (Sweden)

    Juntong Su

    2017-01-01

    Full Text Available We investigate matter creation processes during the reheating period of the early Universe, by using the thermodynamic of open systems. The Universe is assumed to consist of the inflationary scalar field, which, through its decay, generates relativistic matter and pressureless dark matter. The inflationary scalar field transfers its energy to the newly created matter particles, with the field energy decreasing to near zero. The equations governing the irreversible matter creation are obtained by combining the thermodynamics description of the matter creation and the gravitational field equations. The role of the different inflationary scalar field potentials is analyzed by using analytical and numerical methods. The values of the energy densities of relativistic matter and dark matter reach their maximum when the Universe is reheated up to the reheating temperature, which is obtained as a function of the scalar field decay width, the scalar field particle mass, and the cosmological parameters. Particle production leads to the acceleration of the Universe during the reheating phase, with the deceleration parameter showing complex dynamics. Once the energy density of the scalar field becomes negligible with respect to the matter densities, the expansion of the Universe decelerates, and inflation has a graceful exit.

  20. Reheating via Gravitational Particle Production in Simple Models of Quintessence or ΛCDM Inflation

    Science.gov (United States)

    de Haro, Jaume; Aresté Saló, Llibert

    2017-11-01

    We have tested some simple $Lambda$CDM (the same test is also valid for quintessence) inflation models, imposing that they match with the recent observational data provided by the BICEP and Planck's team and leading to a reheating temperature, which is obtained via gravitational particle production after inflation, supporting the nucleosynthesis success.

  1. Supercharged two-cycle engines employing novel single element reciprocating shuttle inlet valve mechanisms and with a variable compression ratio

    Science.gov (United States)

    Wiesen, Bernard (Inventor)

    2008-01-01

    This invention relates to novel reciprocating shuttle inlet valves, effective with every type of two-cycle engine, from small high-speed single cylinder model engines, to large low-speed multiple cylinder engines, employing spark or compression ignition. Also permitting the elimination of out-of-phase piston arrangements to control scavenging and supercharging of opposed-piston engines. The reciprocating shuttle inlet valve (32) and its operating mechanism (34) is constructed as a single and simple uncomplicated member, in combination with the lost-motion abutments, (46) and (48), formed in a piston skirt, obviating the need for any complex mechanisms or auxiliary drives, unaffected by heat, friction, wear or inertial forces. The reciprocating shuttle inlet valve retains the simplicity and advantages of two-cycle engines, while permitting an increase in volumetric efficiency and performance, thereby increasing the range of usefulness of two-cycle engines into many areas that are now dominated by the four-cycle engine.

  2. Performance comparison of single-stage mixed-refrigerant Joule–Thomson cycle and reverse Brayton cycle for cooling 80 to 120 K temperature-distributed heat loads

    Science.gov (United States)

    Wang, H. C.; Chen, G. F.; Gong, M. Q.; Li, X.

    2017-12-01

    Thermodynamic performance comparison of single-stage mixed-refrigerant Joule–Thomson cycle (MJTR) and pure refrigerant reverse Brayton cycle (RBC) for cooling 80 to 120 K temperature-distributed heat loads was conducted in this paper. Nitrogen under various liquefaction pressures was employed as the heat load. The research was conducted under nonideal conditions by exergy analysis methods. Exergy efficiency and volumetric cooling capacity are two main evaluation parameters. Exergy loss distribution in each process of refrigeration cycle was also investigated. The exergy efficiency and volumetric cooling capacity of MJTR were obviously superior to RBC in 90 to 120 K temperature zone, but still inferior to RBC at 80 K. The performance degradation of MJTR was caused by two main reasons: The high fraction of neon resulted in large entropy generation and exergy loss in throttling process. Larger duty and WLMTD lead to larger exergy losses in recuperator.

  3. Ambulatory urodynamic monitoring of women with overactive bladder syndrome during single voiding cycle.

    Science.gov (United States)

    Dokmeci, Fulya; Cetinkaya, S Esra; Seval, M Murat; Dai, Omer

    2017-05-01

    To present data of standardized ambulatory urodynamic monitoring (AUM) performed in women with overactive bladder syndrome (OAB) and to evaluate the relevance of AUM data with clinical findings of the patients. Records of women with symptoms of OAB were retrospectively reviewed (n=249). Of women fulfilling the Overactive Bladder Awareness Tool (OAB-V8) with a score ≥8 and the 3-day voiding diary (VD) with a frequency >7/day (n=167), those who underwent urodynamic investigation were selected (n=76). The data of this study were retrieved from the records of Ankara University Cebeci Hospital and based on the AUM findings of single voiding cycle of women with OAB. AUM, which is among the institutionally approved primary urodynamic investigation methods, is performed with LUNA ambulatory monitoring recorder (MMS™) in the clinical setting with a standardized technique, in reproducing lower urinary tract symptoms of women since 2011. The relationship of the urodynamic data with the clinical findings were evaluated. AUM traces of women (n=76) with OAB revealed 63.1% DO, 64.4% urgency and 77.7% urinary incontinence of which were 14.4% urgency urinary incontinence (UUI), 25% stress urinary incontinence (SUI) and 38.1% mixed urinary incontinence (MUI). OAB patients with DO reported more urinary incontinence episodes/day, nocturia and mixed urinary incontinence in the voiding diary (p<0.04) and had significantly higher irritative symptom bother reflected by the questionnaires (p<0.04). Women with DO were more likely to be postmenopausal (p=0.02) and were found to have more urgency (p<0.001), urgency episodes (p=0.05) and incontinence (urge and mixed) (p<0.001). However, no association was found between the extent of pelvic organ prolapse and the presence of DO. AUM performed with a standardized technique during single voiding cycle seems to be a reliable method in reproducing symptoms of women with OAB. It provides both clinically relevant findings and objective

  4. Optimal design of solid oxide fuel cell, ammonia-water single effect absorption cycle and Rankine steam cycle hybrid system

    Science.gov (United States)

    Mehrpooya, Mehdi; Dehghani, Hossein; Ali Moosavian, S. M.

    2016-02-01

    A combined system containing solid oxide fuel cell-gas turbine power plant, Rankine steam cycle and ammonia-water absorption refrigeration system is introduced and analyzed. In this process, power, heat and cooling are produced. Energy and exergy analyses along with the economic factors are used to distinguish optimum operating point of the system. The developed electrochemical model of the fuel cell is validated with experimental results. Thermodynamic package and main parameters of the absorption refrigeration system are validated. The power output of the system is 500 kW. An optimization problem is defined in order to finding the optimal operating point. Decision variables are current density, temperature of the exhaust gases from the boiler, steam turbine pressure (high and medium), generator temperature and consumed cooling water. Results indicate that electrical efficiency of the combined system is 62.4% (LHV). Produced refrigeration (at -10 °C) and heat recovery are 101 kW and 22.1 kW respectively. Investment cost for the combined system (without absorption cycle) is about 2917 kW-1.

  5. Life cycle cost analysis of single slope hybrid (PV/T) active solar still

    International Nuclear Information System (INIS)

    Kumar, Shiv; Tiwari, G.N.

    2009-01-01

    This paper presents the life cycle cost analysis of the single slope passive and hybrid photovoltaic (PV/T) active solar stills, based on the annual performance at 0.05 m water depth. Effects of various parameters, namely interest rate, life of the system and the maintenance cost have been taken into account. The comparative cost of distilled water produced from passive solar still (Rs. 0.70/kg) is found to be less than hybrid (PV/T) active solar still (Rs. 1.93/kg) for 30 years life time of the systems. The payback periods of the passive and hybrid (PV/T) active solar still are estimated to be in the range of 1.1-6.2 years and 3.3-23.9 years, respectively, based on selling price of distilled water in the range of Rs. 10/kg to Rs. 2/kg. The energy payback time (EPBT) has been estimated as 2.9 and 4.7 years, respectively. (author)

  6. Dynamic expression of the translational machinery during Bacillus subtilis life cycle at a single cell level.

    Directory of Open Access Journals (Sweden)

    Alex Rosenberg

    Full Text Available The ability of bacteria to responsively regulate the expression of translation components is crucial for rapid adaptation to fluctuating environments. Utilizing Bacillus subtilis (B. subtilis as a model organism, we followed the dynamics of the translational machinery at a single cell resolution during growth and differentiation. By comprehensive monitoring the activity of the major rrn promoters and ribosomal protein production, we revealed diverse dynamics between cells grown in rich and poor medium, with the most prominent dissimilarities exhibited during deep stationary phase. Further, the variability pattern of translational activity varied among the cells, being affected by nutrient availability. We have monitored for the first time translational dynamics during the developmental process of sporulation within the two distinct cellular compartments of forespore and mother-cell. Our study uncovers a transient forespore specific increase in expression of translational components. Finally, the contribution of each rrn promoter throughout the bacterium life cycle was found to be relatively constant, implying that differential expression is not the main purpose for the existence of multiple rrn genes. Instead, we propose that coordination of the rrn operons serves as a strategy to rapidly fine tune translational activities in a synchronized fashion to achieve an optimal translation level for a given condition.

  7. Self-phase modulation of a single-cycle terahertz pulse by nonlinear free-carrier response in a semiconductor

    DEFF Research Database (Denmark)

    Turchinovich, Dmitry; Hvam, Jørn Märcher; Hoffmann, Matthias C.

    2012-01-01

    We investigate the self-phase modulation (SPM) of a single-cycle terahertz pulse in a semiconductor, using bulk n-GaAs as a model system. The SPM arises from the heating of free electrons in the electric field of the terahertz pulse, leading to an ultrafast reduction of the plasma frequency...

  8. Single versus double intrauterine insemination in stimulated cycles for subfertile couples : a systematic review based on a Cochrane review

    NARCIS (Netherlands)

    Cantineau, AEP; Heineman, MJ; Cohlen, BJ

    BACKGROUND: The objective of this review was to determine, from the best available evidence, the difference in outcome using single versus double intrauterine insemination (IUI) in stimulated cycles for subfertile couples. METHODS: The principles of the Cochrane Menstrual Disorders and Subfertility

  9. Higgs inflation, reheating and gravitino production in no-scale Supersymmetric GUTs

    International Nuclear Information System (INIS)

    Ellis, John; He, Hong-Jian; Xianyu, Zhong-Zhi

    2016-01-01

    We extend our previous study of supersymmetric Higgs inflation in the context of no-scale supergravity and grand unification, to include models based on the flipped SU(5) and the Pati-Salam group. Like the previous SU(5) GUT model, these yield a class of inflation models whose inflation predictions interpolate between those of the quadratic chaotic inflation and Starobinsky-like inflation, while avoiding tension with proton decay limits. We further analyse the reheating process in these models, and derive the number of e-folds, which is independent of the reheating temperature. We derive the corresponding predictions for the scalar tilt and the tensor-to-scalar ratio in cosmic microwave background perturbations, as well as discussing the gravitino production following inflation.

  10. Higgs Inflation, Reheating and Gravitino Production in No-Scale Supersymmetric GUTs

    CERN Document Server

    Ellis, John; Xianyu, Zhong-Zhi

    2016-08-30

    We extend our previous study of supersymmetric Higgs inflation in the context of no-scale supergravity and grand unification, to include models based on the flipped SU(5) and the Pati-Salam group. Like the previous SU(5) GUT model, these yield a class of inflation models whose inflation predictions interpolate between those of the quadratic chaotic inflation and Starobinsky-like inflation, while also avoiding tension with proton decay limits. We further analyse the reheating process in these models, and derive the number of $e$-folds, which is independent of the reheating temperature. We derive the corresponding predictions for the scalar tilt and the tensor-to-scalar ratio in cosmic microwave background perturbations, and also discuss gravitino production following inflation.

  11. Calculations of Inflaton Decays and Reheating: with Applications to No-Scale Inflation Models

    CERN Document Server

    Ellis, John; Nanopoulos, Dimitri V; Olive, Keith A

    2015-01-01

    We discuss inflaton decays and reheating in no-scale Starobinsky-like models of inflation, calculating the effective equation-of-state parameter, $w$, during the epoch of inflaton decay, the reheating temperature, $T_{\\rm reh}$, and the number of inflationary e-folds, $N_*$, comparing analytical approximations with numerical calculations. We then illustrate these results with applications to models based on no-scale supergravity and motivated by generic string compactifications, including scenarios where the inflaton is identified as an untwisted-sector matter field with direct Yukawa couplings to MSSM fields, and where the inflaton decays via gravitational-strength interactions. Finally, we use our results to discuss the constraints on these models imposed by present measurements of the scalar spectral index $n_s$ and the tensor-to-scalar perturbation ratio $r$, converting them into constraints on $N_*$, the inflaton decay rate and other parameters of specific no-scale inflationary models.

  12. Reheat cracking in 1/2 CrMoV steel. Heat affected zones

    International Nuclear Information System (INIS)

    Batte, A.D.; Miller, R.C.; Murphy, M.C.

    1976-01-01

    Low alloy creep resisting steels are inherently susceptible to cracking during stress relief heat treatment (reheat cracking) though few welds give rise to problems in manufacture or service. Mechanical tests on simulated affected zone structures in CrMoV forgings have shown that cracking occurs when the high temperature ductility is inadequate to accommodate the residual welding strain. Differences in susceptibility result from differences in heat affected zone grain size if the purity level is sufficiently high; reheat cracking may then be avoided by ensuring complete grain refinement during welding. The susceptibility of a lower purity forging was insensitive to grain size; heat affected zone refinement is unlikely to eliminate cracking in such steel. (orig.) [de

  13. Energy conservation in reheating furnaces by reducing scrap and scale formation; Kuumamuokkauksen energiasaeaestoet romun maeaeraeae ja hilseilyae vaehentaemaellae

    Energy Technology Data Exchange (ETDEWEB)

    Kivivuori, S.; Savolainen, P.; Fredriksson, J.; Paavola, J. [Helsinki Univ. of Technology, Otaniemi (Finland). Lab. of Materials Processing and Powder Metallurgy

    1996-12-31

    The main objective of the project `Energy Savings in Reheating Furnaces by Reducing Scrap and Scale Formation` is to reduce energy consumption and environmental harms in reheating and rolling of steel. This was done by analysing the different atmospheres in reheating furnaces of the steel companies participating in this project. These atmospheres were then simulated in a laboratory furnace. Scale formation tests with different steel grades were then carried out in these atmospheres. Scale removal tests were done to some steel grades too. The results showed that lower oxygen content - as expected - decreases oxidation despite the even higher carbondioxide content in the atmosphere. Lower oxygen content may cause difficulties in scale removal. This however is highly dependent on the steel grade. Heat treatment tests showed the effect of increased temperature and furnace time on decarburization. Some energy savings was obtained in fuel consumption by optimising the operation parameters and the atmosphere steadier in different reheating furnaces. (orig.)

  14. Efficiency of steam reheating in heat recovery steam generator at thermal power plant with gas turbine topping

    Directory of Open Access Journals (Sweden)

    Romashova Olga

    2017-01-01

    Full Text Available Possibility of using alternative option to the displacement of regenerative heating is analyzed in this paper: application of heat recovery steam generator’s (HRSG thermal power for reheating of working medium that has passed steam turbine.

  15. Supersymmetric mass spectra for gravitino dark matter with a high reheating temperature

    Energy Technology Data Exchange (ETDEWEB)

    Covi, L. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Olechowski, M.; Pokorski, S.; Turzynski, K. [Warsaw Univ. (Poland). Inst. of Theoretical Physics; Wells, J.D. [European Organization for Nuclear Research (CERN), Geneva (Switzerland); Michigan Univ., Ann Arbor, MI (United States). Michigan Center for Theoretical Physics

    2010-09-15

    Supersymmetric theories with gravitino dark matter generally do not allow the high reheating temperature required by thermal leptogenesis without running afoul of relic abundance or big bang nucleosynthesis constraints. We report on a successful search for parameter space that does satisfy these requirements. The main implication is the near degeneracy of the gluino with the other neutralinos in the spectrum. The leading discovery channel at the LHC for this scenario is through monojet plus missing energy events. (orig.)

  16. A new method for estimating heat flux in superheater and reheater tubes

    Energy Technology Data Exchange (ETDEWEB)

    Purbolaksono, J. [Department of Mechanical Engineering, Universiti Tenaga Nasional, km 7 Jalan Kajang-Puchong, Kajang 43009, Selangor (Malaysia)], E-mail: judha@uniten.edu.my; Khinani, A.; Rashid, A.Z.; Ali, A.A. [Department of Mechanical Engineering, Universiti Tenaga Nasional, km 7 Jalan Kajang-Puchong, Kajang 43009, Selangor (Malaysia); Ahmad, J. [Kapar Energy Ventures Sdn Bhd, Jalan Tok Muda, Kapar 42200, Selangor (Malaysia); Nordin, N.F. [TNB Research Sdn Bhd, No. 1 Lorong Air Hitam, Kajang 43000, Selangor (Malaysia)

    2009-10-15

    In this paper a procedure on how to estimate the heat flux in superheater and reheater tubes utilizing the empirical formula and the finite element modeling is proposed. An iterative procedure consisting of empirical formulae and numerical simulation is used to determine heat flux as both temperature and scale thickness increase over period of time. Estimation results of the heat flux over period of time for two different design temperatures of the steam and different heat transfer parameters are presented.

  17. Economic efficiency of a gas-turbine topping for steam reheating at heating turbo-installations

    OpenAIRE

    Romashova Olga; Belyaev Leonid; Tubolev Aleksandr; Skrebatun Egor

    2017-01-01

    The article considers the ways to improve the operating efficiency of conventional combined heat power plants using gas-turbine topping scheme allowing heat utilization of flue gases for steam reheating in the waste-heat steam boiler. The calculating analysis was performed for a steam-turbine power generating unit with a turbine of the Т-110/120-130 brand name intended for various modes of operation.

  18. DNS of flame stabilization assisted by auto-ignition at reheat conditions

    Science.gov (United States)

    Konduri, Aditya; Gruber, Andrea; Chen, Jacqueline

    2017-11-01

    Staged gas turbines with two sequential combustion chambers are being developed for power generation for their ability to achieve low emissions within a wide operational range while conserving high thermal efficiency. A particular implementation of the sequential combustion concept is characterized by a ''reheat'' combustion stage downstream of a first premixed-type combustor. Hot exhaust gases from the first stage are mixed with fuel in a mixing section, which provides the inlet conditions for the second-stage reheat combustor. DNS of flame stabilization regimes in the reheat burner, i.e. the combustor including the mixing section (duct-in-a-duct), at idealized conditions is performed using a detailed hydrogen-air mechanism. Results show that combustion occurs in two distinct modes. The first mode is an auto-ignition mode, whereby the vitiated oxidant facilitates the auto-ignition of the fuel in the mixing section. The second mode combines both auto-ignition and flame propagation, with auto-ignition occurring at and around the centerline of the combustor while flame propagation is stabilized at the recirculation zones near the corners. Chemical explosive mode analysis is employed to quantify the contribution of auto-ignition to the combustion rate relative to flame propagation. We acknowledge the sponsorship of the DOE Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences, and Biosciences and the computing time from NERSC.

  19. Study of structure formation and reheating in the D3/D7 brane inflation model

    International Nuclear Information System (INIS)

    Brandenberger, Robert H.; Dasgupta, Keshav; Davis, Anne-Christine

    2008-01-01

    We study the spectrum of cosmological fluctuations in the D3/D7 brane inflationary universe with particular attention to the parametric excitation of entropy modes during the reheating stage. The same tachyonic instability which renders reheating in this model very rapidly leads to an exponential growth of entropy fluctuations during the preheating stage which in turn may induce a large contribution to the large-scale curvature fluctuations. We take into account the effects of long wavelength quantum fluctuations in the matter fields. As part of this work, we perform an analytical analysis of the reheating process. We find that the initial stage of preheating proceeds by the tachyonic instability channel. An upper bound on the time it takes for the energy initially stored in the inflaton field to convert into fluctuations is obtained by neglecting the local fluctuations produced during the period of tachyonic decay and analyzing the decay of the residual homogeneous field oscillations, which proceeds by parametric resonance. We show that, in spite of the fact that the resonance is of the narrow-band type, it is sufficiently efficient to rapidly convert most of the energy of the background fields into matter fluctuations.

  20. Critical firing and misfiring boundary in a spark ignition methanol engine during cold start based on single cycle fuel injection

    International Nuclear Information System (INIS)

    Li, Zhaohui; Gong, Changming; Qu, Xiang; Liu, Fenghua; Sun, Jingzhen; Wang, Kang; Li, Yufeng

    2015-01-01

    The influence of the mass of methanol injected per cycle, ambient temperature, injection and ignition timing, preheating methods, and supplying additional liquefied petroleum gas (LPG) injection into the intake manifold on the critical firing and misfiring boundary of an electronically injection controlled spark ignition (SI) methanol engine during cold start were investigated experimentally based on a single cycle fuel injection with cycle-by-cycle control strategy. The critical firing and misfiring boundary was restricted by all parameters. For ambient temperatures below 16 °C, methanol engines must use auxiliary start-aids during cold start. Optimal control of the methanol injection and ignition timing can realize ideal next cycle firing combustion after injection. Resistance wire and glow plug preheating can provide critical firing down to ambient temperatures of 5 °C and 0 °C, respectively. Using an additional LPG injection into the intake manifold can provide critical firing down to an ambient temperature of −13 °C during cold start. As the ambient temperature decreases, the optimal angle difference between methanol injection timing and LPG injection timing for critical firing of a methanol engine increases rapidly during cold start. - Highlights: • A single cycle fuel injection and cycle-by-cycle control strategy are used to study. • In-cylinder pressure and instantaneous speed were used to determine firing boundary. • For the ambient temperatures below 16 °C, an auxiliary start-aids must be used. • A preheating and additional LPG were used to expand critical firing boundary. • Additional LPG can result in critical firing down to ambient temperature of −13 °C

  1. Administration of single-dose GnRH agonist in the luteal phase in ICSI cycles: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Oliveira João

    2010-09-01

    Full Text Available Abstract Background The effects of gonadotrophin-releasing hormone agonist (GnRH-a administered in the luteal phase remains controversial. This meta-analysis aimed to evaluate the effect of the administration of a single-dose of GnRH-a in the luteal phase on ICSI clinical outcomes. Methods The research strategy included the online search of databases. Only randomized studies were included. The outcomes analyzed were implantation rate, clinical pregnancy rate (CPR per transfer and ongoing pregnancy rate. The fixed effects model was used for odds ratio. In all trials, a single dose of GnRH-a was administered at day 5/6 after ICSI procedures. Results All cycles presented statistically significantly higher rates of implantation (P Conclusions These findings demonstrate that the luteal-phase single-dose GnRH-a administration can increase implantation rate in all cycles and CPR per transfer and ongoing pregnancy rate in cycles with GnRH antagonist ovarian stimulation protocol. Nevertheless, by considering the heterogeneity between the trials, it seems premature to recommend the use of GnRH-a in the luteal phase. Additional randomized controlled trials are necessary before evidence-based recommendations can be provided.

  2. Universal route to optimal few- to single-cycle pulse generation in hollow-core fiber compressors.

    Science.gov (United States)

    Conejero Jarque, E; San Roman, J; Silva, F; Romero, R; Holgado, W; Gonzalez-Galicia, M A; Alonso, B; Sola, I J; Crespo, H

    2018-02-02

    Gas-filled hollow-core fiber (HCF) pulse post-compressors generating few- to single-cycle pulses are a key enabling tool for attosecond science and ultrafast spectroscopy. Achieving optimum performance in this regime can be extremely challenging due to the ultra-broad bandwidth of the pulses and the need of an adequate temporal diagnostic. These difficulties have hindered the full exploitation of HCF post-compressors, namely the generation of stable and high-quality near-Fourier-transform-limited pulses. Here we show that, independently of conditions such as the type of gas or the laser system used, there is a universal route to obtain the shortest stable output pulse down to the single-cycle regime. Numerical simulations and experimental measurements performed with the dispersion-scan technique reveal that, in quite general conditions, post-compressed pulses exhibit a residual third-order dispersion intrinsic to optimum nonlinear propagation within the fiber, in agreement with measurements independently performed in several laboratories around the world. The understanding of this effect and its adequate correction, e.g. using simple transparent optical media, enables achieving high-quality post-compressed pulses with only minor changes in existing setups. These optimized sources have impact in many fields of science and technology and should enable new and exciting applications in the few- to single-cycle pulse regime.

  3. A new six stroke single cylinder diesel engine referring Rankine cycle

    International Nuclear Information System (INIS)

    Chen, Hao; Guo, Qi; Yang, Lu; Liu, Shenghua; Xie, Xuliang; Chen, Zhaoyang; Liu, Zengqiang

    2015-01-01

    Six stroke engine presented by Conklin and Szybist is an effective way to recover energy of exhaust gas by adding a partial exhaust stroke and steam expansion stroke. Characteristics of the engine are analyzed and its disadvantages are pointed out. A new six stroke diesel engine is presented here. It refers rankine cycle inside cylinder. Total exhaust gas is recompressed and at a relatively low back pressure in the fourth stroke water is injected to which maintains liquid phase until the piston moves to the TDC. At c′ 720 °CA (crank angle) the water becomes saturated. An ideal thermodynamics model of exhaust gas compression, water injection and expansion is constructed to investigate this modification. Properties at characteristic points are calculated to determine the increased indicated work. Results show that the work increases with the advance of water injection timing and the quality of water. The cycle is more efficient and the new engine has potential for saving energy. Moreover, it is forecasted that HC and PM emissions may reform with steam in reality and H 2 is produced which will react with NO X . - Highlights: • A new six stroke diesel engine is introduced and a new ideal cycle is constructed. • Increased indicated work of the cycle proves that the cycle is more efficient. • In reality steam may reform with HC and PM and produced H 2 may react with NO X emission. • The engine has the potential for energy saving and emission reducing

  4. The Single Cell Proteome Project - Cell-Cycle Dependent Protein Expression in Breast Cancer Cell Lines

    National Research Council Canada - National Science Library

    Dovichi, Norman J

    2005-01-01

    .... Capillary sieving electrophoresis and capillary micellar electrophoresis were used to characterize proteins in single cells in one-dimensional separations, while the two techniques were combined...

  5. Experimental Comparison Of Working Fluids For Organic Rankine Cycle With Single-Screw Expander

    OpenAIRE

    Gusev, Sergei; Ziviani, Davide; Bell, Ian; De Paepe, Michel; van den Broek, Martijn

    2014-01-01

    This paper describes the behavior of an Organic Rankine Cycle (ORC) fed by a heat source with adaptable temperature and mass flow. For a suitable choice of working fluid, the setting of its evaporation pressure is crucial for the performance of an ORC installation. The higher the evaporation pressure, the higher the cycle efficiency on the one hand, but the lower the energy recovered from the heat source due to a higher outlet temperature on the other hand. An optimum has to be found to achie...

  6. Optimum Envelope of a Single-Family House Based on Life Cycle Analysis

    OpenAIRE

    Marie-Claude Hamelin; Radu Zmeureanu

    2014-01-01

    This paper describes the methodology used for the life cycle cost (LCC) and life cycle energy (LCE) analyses of the case study house in Quebec, Canada. The TRNSYS energy analysis program is coupled with GenOpt, a general purpose optimization program, for the purpose of this study. The particle swarm optimization (PSO) algorithm is used for the search for the optimum solution. Results show that the optimum levels of insulation should be higher than the reference values, even for the case of LC...

  7. Single and combined effects of beetroot juice and caffeine supplementation on cycling time trial performance.

    Science.gov (United States)

    Lane, Stephen C; Hawley, John A; Desbrow, Ben; Jones, Andrew M; Blackwell, James R; Ross, Megan L; Zemski, Adam J; Burke, Louise M

    2014-09-01

    Both caffeine and beetroot juice have ergogenic effects on endurance cycling performance. We investigated whether there is an additive effect of these supplements on the performance of a cycling time trial (TT) simulating the 2012 London Olympic Games course. Twelve male and 12 female competitive cyclists each completed 4 experimental trials in a double-blind Latin square design. Trials were undertaken with a caffeinated gum (CAFF) (3 mg·kg(-1) body mass (BM), 40 min prior to the TT), concentrated beetroot juice supplementation (BJ) (8.4 mmol of nitrate (NO3(-)), 2 h prior to the TT), caffeine plus beetroot juice (CAFF+BJ), or a control (CONT). Subjects completed the TT (females: 29.35 km; males: 43.83 km) on a laboratory cycle ergometer under conditions of best practice nutrition: following a carbohydrate-rich pre-event meal, with the ingestion of a carbohydrate-electrolyte drink and regular oral carbohydrate contact during the TT. Compared with CONT, power output was significantly enhanced after CAFF+BJ and CAFF (3.0% and 3.9%, respectively, p caffeine (-0.9%, p = 0.4 compared with CAFF). We conclude that caffeine (3 mg·kg(-1) BM) administered in the form of a caffeinated gum increased cycling TT performance lasting ∼50-60 min by ∼3%-4% in both males and females. Beetroot juice supplementation was not ergogenic under the conditions of this study.

  8. Lineage correlations of single cell division time as a probe of cell-cycle dynamics.

    Science.gov (United States)

    Sandler, Oded; Mizrahi, Sivan Pearl; Weiss, Noga; Agam, Oded; Simon, Itamar; Balaban, Nathalie Q

    2015-03-26

    Stochastic processes in cells are associated with fluctuations in mRNA, protein production and degradation, noisy partition of cellular components at division, and other cell processes. Variability within a clonal population of cells originates from such stochastic processes, which may be amplified or reduced by deterministic factors. Cell-to-cell variability, such as that seen in the heterogeneous response of bacteria to antibiotics, or of cancer cells to treatment, is understood as the inevitable consequence of stochasticity. Variability in cell-cycle duration was observed long ago; however, its sources are still unknown. A central question is whether the variance of the observed distribution originates from stochastic processes, or whether it arises mostly from a deterministic process that only appears to be random. A surprising feature of cell-cycle-duration inheritance is that it seems to be lost within one generation but to be still present in the next generation, generating poor correlation between mother and daughter cells but high correlation between cousin cells. This observation suggests the existence of underlying deterministic factors that determine the main part of cell-to-cell variability. We developed an experimental system that precisely measures the cell-cycle duration of thousands of mammalian cells along several generations and a mathematical framework that allows discrimination between stochastic and deterministic processes in lineages of cells. We show that the inter- and intra-generation correlations reveal complex inheritance of the cell-cycle duration. Finally, we build a deterministic nonlinear toy model for cell-cycle inheritance that reproduces the main features of our data. Our approach constitutes a general method to identify deterministic variability in lineages of cells or organisms, which may help to predict and, eventually, reduce cell-to-cell heterogeneity in various systems, such as cancer cells under treatment.

  9. Weighting and Aggregation in Life Cycle Assessment: Do Present Aggregated Single Scores Provide Correct Decision Support?

    DEFF Research Database (Denmark)

    Kalbar, Pradip; Birkved, Morten; Nygaard, Simon Elsborg

    2016-01-01

    approach was adopted to facilitate identification of three main problems related to the single-score calculation approach. The prevailing ReCiPe single-score calculation method does not account for either the effect of so-called dominating alternatives (i.e., alternatives having high values across all...... endpoints) or the interdependency of the indicators being aggregated. It was also found that the simple linear weighted sum method, presently used for obtaining single scores, is not capable of accounting for the effect of weighting schemes and thus cannot realistically represent stakeholders' perspectives...

  10. Using single cell cultivation system for on-chip monitoring of the interdivision timer in Chlamydomonas reinhardtii cell cycle

    Directory of Open Access Journals (Sweden)

    Soloviev Mikhail

    2010-09-01

    Full Text Available Abstract Regulation of cell cycle progression in changing environments is vital for cell survival and maintenance, and different regulation mechanisms based on cell size and cell cycle time have been proposed. To determine the mechanism of cell cycle regulation in the unicellular green algae Chlamydomonas reinhardtii, we developed an on-chip single-cell cultivation system that allows for the strict control of the extracellular environment. We divided the Chlamydomonas cell cycle into interdivision and division phases on the basis of changes in cell size and found that, regardless of the amount of photosynthetically active radiation (PAR and the extent of illumination, the length of the interdivision phase was inversely proportional to the rate of increase of cell volume. Their product remains constant indicating the existence of an 'interdivision timer'. The length of the division phase, in contrast, remained nearly constant. Cells cultivated under light-dark-light conditions did not divide unless they had grown to twice their initial volume during the first light period. This indicates the existence of a 'commitment sizer'. The ratio of the cell volume at the beginning of the division phase to the initial cell volume determined the number of daughter cells, indicating the existence of a 'mitotic sizer'.

  11. Optimum Envelope of a Single-Family House Based on Life Cycle Analysis

    Directory of Open Access Journals (Sweden)

    Marie-Claude Hamelin

    2014-04-01

    Full Text Available This paper describes the methodology used for the life cycle cost (LCC and life cycle energy (LCE analyses of the case study house in Quebec, Canada. The TRNSYS energy analysis program is coupled with GenOpt, a general purpose optimization program, for the purpose of this study. The particle swarm optimization (PSO algorithm is used for the search for the optimum solution. Results show that the optimum levels of insulation should be higher than the reference values, even for the case of LCC analysis. The results are for the most part still valid if electricity costs are assumed to increase below the inflation rate for the duration of the study period.

  12. Bottoming organic Rankine cycle configurations to increase Internal Combustion Engines power output from cooling water waste heat recovery

    International Nuclear Information System (INIS)

    Peris, Bernardo; Navarro-Esbrí, Joaquín; Molés, Francisco

    2013-01-01

    This work is focused on waste heat recovery of jacket cooling water from Internal Combustion Engines (ICEs). Cooling water heat does not always find use due to its low temperature, typically around 90 °C, and usually is rejected to the ambient despite its high thermal power. An efficient way to take benefit from the ICE cooling water waste heat can be to increase the power output through suitable bottoming Organic Rankine Cycles (ORCs). Thereby, this work simulates six configurations using ten non flammable working fluids and evaluates their performances in efficiency, safety, cost and environmental terms. Results show that the Double Regenerative ORC using SES36 gets the maximum net efficiency of 7.15%, incrementing the ICE electrical efficiency up to 5.3%, although requires duplicating the number of main components and high turbine size. A more rigorous analysis, based on the system feasibility, shows that small improvements in the basic cycle provide similar gains compared to the most complex schemes proposed. So, the single Regenerative ORC using R236fa and the Reheat Regenerative ORC using R134a seem suitable cycles which provide a net efficiency of 6.55%, incrementing the ICE electrical efficiency up to 4.9%. -- Highlights: • Suitable bottoming cycles for ICE cooling water waste heat recovery are studied. • Non flammable working fluids and various ORC configurations are evaluated. • Double regenerative cycle using SES36 is the most efficient configuration. • Regenerative and reheat regenerative ORCs seem feasible cycles. • Electrical efficiency of the ICE can be improved up to 5.3%

  13. Single SOA based 16 DWDM channels all-optical NRZ-to-RZ format conversions with different duty cycles.

    Science.gov (United States)

    Yu, Yu; Zhang, Xinliang; Rosas-Fernández, J B; Huang, Dexiu; Penty, R V; White, I H

    2008-09-29

    We demonstrate simultaneous NRZ-to-RZ conversion for 16 DWDM channels, using a single SOA and a subsequent delay interferometer (DI) acting as a comb-like filter to control the obtained pulse-width for all of the channels. The SOA is operated in deep saturation, resulting in weak cross gain modulation and cross phase modulation induced crosstalk between different NRZ channels. By adjusting the detuning between the peaks in the DI spectrum and each corresponding carrier, good quality RZ signals with different duty cycles can be achieved. Bit-error-rate measurements show negative power penalties for the obtained RZ signals with different duty cycles. Significant timing jitter reductions for all channels show the good regenerative performance of the proposed converter.

  14. Time-lapse electrical impedance spectroscopy for monitoring the cell cycle of single immobilized S. pombe cells

    Science.gov (United States)

    Zhu, Zhen; Frey, Olivier; Haandbaek, Niels; Franke, Felix; Rudolf, Fabian; Hierlemann, Andreas

    2015-11-01

    As a complement and alternative to optical methods, wide-band electrical impedance spectroscopy (EIS) enables multi-parameter, label-free and real-time detection of cellular and subcellular features. We report on a microfluidics-based system designed to reliably capture single rod-shaped Schizosaccharomyces pombe cells by applying suction through orifices in a channel wall. The system enables subsequent culturing of immobilized cells in an upright position, while dynamic changes in cell-cycle state and morphology were continuously monitored through EIS over a broad frequency range. Besides measuring cell growth, clear impedance signals for nuclear division have been obtained. The EIS system has been characterized with respect to sensitivity and detection limits. The spatial resolution in measuring cell length was 0.25 μm, which corresponds to approximately a 5-min interval of cell growth under standard conditions. The comprehensive impedance data sets were also used to determine the occurrence of nuclear division and cytokinesis. The obtained results have been validated through concurrent confocal imaging and plausibilized through comparison with finite-element modeling data. The possibility to monitor cellular and intracellular features of single S. pombe cells during the cell cycle at high spatiotemporal resolution renders the presented microfluidics-based EIS system a suitable tool for dynamic single-cell investigations.

  15. High-energy electron emission from metallic nano-tips driven by intense single-cycle terahertz pulses

    Science.gov (United States)

    Li, Sha; Jones, R. R.

    2016-01-01

    Electrons ejected from atoms and subsequently driven to high energies in strong laser fields enable techniques from attosecond pulse generation to imaging with rescattered electrons. Analogous processes govern strong-field electron emission from nanostructures, where long wavelength radiation and large local field enhancements hold the promise for producing electrons with substantially higher energies, allowing for higher resolution time-resolved imaging. Here we report on the use of single-cycle terahertz pulses to drive electron emission from unbiased nano-tips. Energies exceeding 5 keV are observed, substantially greater than previously attained at higher drive frequencies. Despite large differences in the magnitude of the respective local fields, we find that the maximum electron energies are only weakly dependent on the tip radius, for 10 nmsingle-cycle nature of the field, the high-energy electron emission is predicted to be confined to a single burst, potentially enabling a variety of applications. PMID:27830701

  16. Transient impairments in single muscle fibre contractile function after prolonged cycling in elite endurance athletes

    DEFF Research Database (Denmark)

    Hvid, L G; Gejl, Kasper Degn; Bech, R D

    2013-01-01

    Prolonged muscle activity impairs whole-muscle performance and function. However, little is known about the effects of prolonged muscle activity on the contractile function of human single muscle fibres. The purpose of this study was to investigate the effects of prolonged exercise and subsequent...

  17. Microstructure and Impact Toughness of the Intercritically Reheated Coarse-grained Heat Affected Zone of 13MnNiMoR Steel

    Science.gov (United States)

    Han, Yang; Jinbo, Qu

    The microstructure and impact toughness of intercritically reheated coarse-grained heat affected zone (ICCGHAZ) of 13MnNiMoR and the effect of post-welding heat treatment (PWHT) process were investigated by means of welding thermal simulation test. The result shows that after the first welding thermal cycle, the microstructure of the coarse-grained heat affected zone (CGHAZ) mainly consists of granular bainite and lath bainite, with good impact toughness. After the second thermal cycle with a peak temperature of 650 to 700°C, the CGHAZ microstructure experiences a tempering process and its impact toughness improves due to the precipitation of carbides and reduction of dislocations. With a second peak temperature of 750 to 850°C, part of the CGHAZ microstructure retransforms to austenite and during cooling, martensite-austenite (MA) constituents forms along grain boundaries in the ICCGHAZ microstructure, leading to a sharp drop of toughness. When the second thermal cycle peak temperature is up to 900°C, the CGHAZ microstructure is fully austenitized, and the final microstructure mainly consists of ferrite and granular bainite. After a PWHT process in the temperature range of 560 to 640°C, the impact toughness of ICCGHAZ is markedly improved, primarily due to the decomposition of MA constituents.

  18. Factors affecting 223Ra therapy: clinical experience after 532 cycles from a single institution

    International Nuclear Information System (INIS)

    The aim of this study was to identify baseline features that predict outcome in 223 Ra therapy. We retrospectively reviewed 110 patients with metastatic castration-resistant prostate cancer treated with 223 Ra. End points were overall survival (OS), progression-free survival (PFS), bone event-free survival (BeFS), and bone marrow failure (BMF). The following parameters were evaluated prior to the first 223 Ra cycle: serum levels of hemoglobin (Hb), prostate-specific antigen (PSA), alkaline phosphatase (ALP), Eastern Cooperative Oncology Group (ECOG) status, pain score, use of chemotherapy, and external beam radiation therapy (EBRT). During/after 223 Ra we evaluated: the total number of radium cycles (Ra Tot ), the PSA doubling time (PSA DT ), and the use of chemotherapy, EBRT, abiraterone, and enzalutamide. A significant reduction of ALP (p < 0.001) and pain score (p = 0.041) occurred throughout the 223 Ra cycles. The risk of progression was associated with declining ECOG status [hazard ratio (HR) = 3.79; p < 0.001] and decrease in PSA DT (HR = 8.22; p < 0.001). Ra Tot , ALP, initial ECOG status, initial pain score, and use of abiraterone were associated with OS (p ≤ 0.008), PFS (p ≤ 0.003), and BeFS (p ≤ 0.020). Ra Tot , ALP, initial ECOG status, and initial pain score were significantly associated with BMF (p ≤ 0.001) as well as Hb (p < 0.001) and EBRT (p = 0.009). On multivariable analysis, only Ra Tot and abiraterone remained significantly associated with OS (p < 0.001; p = 0.033, respectively), PFS (p < 0.001; p = 0.041, respectively), and BeFS (p < 0.001; p = 0.019, respectively). Additionally, Ra Tot (p = 0.027) and EBRT (p = 0.013) remained significantly associated with BMF. Concomitant use of abiraterone and 223 Ra seems to have a beneficial effect, while the EBRT may increase the risk of BMF. (orig.)

  19. Factors affecting {sup 223}Ra therapy: clinical experience after 532 cycles from a single institution

    Energy Technology Data Exchange (ETDEWEB)

    Etchebehere, Elba C. [The University of Texas MD Anderson Cancer Center, Department of Nuclear Medicine, Houston, TX (United States); Campinas State University (Unicamp), Department of Nuclear Medicine, Campinas (Brazil); Milton, Denai R. [The University of Texas MD Anderson Cancer Center, Department of Biostatistics, Houston, TX (United States); Araujo, John C. [The University of Texas MD Anderson Cancer Center, Department of Genitourinary Medical Oncology, Houston, TX (United States); Swanston, Nancy M.; Macapinlac, Homer A.; Rohren, Eric M. [The University of Texas MD Anderson Cancer Center, Department of Nuclear Medicine, Houston, TX (United States)

    2016-01-15

    The aim of this study was to identify baseline features that predict outcome in {sup 223}Ra therapy. We retrospectively reviewed 110 patients with metastatic castration-resistant prostate cancer treated with {sup 223}Ra. End points were overall survival (OS), progression-free survival (PFS), bone event-free survival (BeFS), and bone marrow failure (BMF). The following parameters were evaluated prior to the first {sup 223}Ra cycle: serum levels of hemoglobin (Hb), prostate-specific antigen (PSA), alkaline phosphatase (ALP), Eastern Cooperative Oncology Group (ECOG) status, pain score, use of chemotherapy, and external beam radiation therapy (EBRT). During/after {sup 223}Ra we evaluated: the total number of radium cycles (Ra{sub Tot}), the PSA doubling time (PSA{sub DT}), and the use of chemotherapy, EBRT, abiraterone, and enzalutamide. A significant reduction of ALP (p < 0.001) and pain score (p = 0.041) occurred throughout the {sup 223} Ra cycles. The risk of progression was associated with declining ECOG status [hazard ratio (HR) = 3.79; p < 0.001] and decrease in PSA{sub DT} (HR = 8.22; p < 0.001). Ra{sub Tot}, ALP, initial ECOG status, initial pain score, and use of abiraterone were associated with OS (p ≤ 0.008), PFS (p ≤ 0.003), and BeFS (p ≤ 0.020). Ra{sub Tot}, ALP, initial ECOG status, and initial pain score were significantly associated with BMF (p ≤ 0.001) as well as Hb (p < 0.001) and EBRT (p = 0.009). On multivariable analysis, only Ra{sub Tot} and abiraterone remained significantly associated with OS (p < 0.001; p = 0.033, respectively), PFS (p < 0.001; p = 0.041, respectively), and BeFS (p < 0.001; p = 0.019, respectively). Additionally, Ra{sub Tot} (p = 0.027) and EBRT (p = 0.013) remained significantly associated with BMF. Concomitant use of abiraterone and {sup 223}Ra seems to have a beneficial effect, while the EBRT may increase the risk of BMF. (orig.)

  20. Interaction of high cycle fatigue with high temperature creep in superalloy single crystals

    Czech Academy of Sciences Publication Activity Database

    Lukáš, Petr; Kunz, Ludvík; Svoboda, Milan

    2002-01-01

    Roč. 93, č. 7 (2002), s. 661-665 ISSN 0044-3093 R&D Projects: GA AV ČR IAA2041002; GA AV ČR KSK1010104 Institutional research plan: CEZ:AV0Z2041904 Keywords : Single crystals * Creep/fatigue interaction * Persistent slip bands Subject RIV: JL - Materials Fatigue, Friction Mechanics Impact factor: 0.636, year: 2002

  1. Performance analysis of a potassium-steam two stage vapour cycle

    International Nuclear Information System (INIS)

    Mitachi, Kohshi; Saito, Takeshi

    1983-01-01

    It is an important subject to raise the thermal efficiency in thermal power plants. In present thermal power plants which use steam cycle, the plant thermal efficiency has already reached 41 to 42 %, steam temperature being 839 K, and steam pressure being 24.2 MPa. That is, the thermal efficiency in a steam cycle is facing a limit. In this study, analysis was made on the performance of metal vapour/steam two-stage Rankine cycle obtained by combining a metal vapour cycle with a present steam cycle. Three different combinations using high temperature potassium regenerative cycle and low temperature steam regenerative cycle, potassium regenerative cycle and steam reheat and regenerative cycle, and potassium bleed cycle and steam reheat and regenerative cycle were systematically analyzed for the overall thermal efficiency, the output ratio and the flow rate ratio, when the inlet temperature of a potassium turbine, the temperature of a potassium condenser, and others were varied. Though the overall thermal efficiency was improved by lowering the condensing temperature of potassium vapour, it is limited by the construction because the specific volume of potassium in low pressure section increases greatly. In the combinatipn of potassium vapour regenerative cycle with steam regenerative cycle, the overall thermal efficiency can be 58.5 %, and also 60.2 % if steam reheat and regenerative cycle is employed. If a cycle to heat steam with the bled vapor out of a potassium vapour cycle is adopted, the overall thermal efficiency of 63.3 % is expected. (Wakatsuki, Y.)

  2. Coefficient of Performance Optimization of Single-Effect Lithium-Bromide Absorption Cycle Heat Pumps

    DEFF Research Database (Denmark)

    Vinther, Kasper; Just Nielsen, Rene; Nielsen, Kirsten Mølgaard

    2015-01-01

    In this paper, we investigate the coefficient of performance (COP) of a LiBr absorption cycle heat pump under different operating conditions. The investigation is carried out using a dynamical model fitted against data recorded from an actual heat pump used for district heating in S......⊘nderborg, Denmark. Since the model is too complex to study analytically, we vary different input variables within the permissible operating range of the heat pump and evaluate COP at the resulting steady-state operating points. It is found that the best set-point for each individual input is located at an extreme...... value of the investigated permissible range, and that the COP optimization is likely to be a convex problem. Further, we exploit this observation to propose a simple offline set-point optimization algorithm, which can be used as an automated assistance for the plant operator to optimize steady...

  3. Influence of Cooling Holes Distribution on High Cycle Fatigue Fracture Behavior of DD6 Single Crystal Superalloy

    Directory of Open Access Journals (Sweden)

    HU Chun-yan

    2017-04-01

    Full Text Available The modeling air-cooled turbine blades specimens of DD6 single crystal superalloy with different distributions of cooling film holes were used to study the high cycle fatigue properties at room temperature. The SEM fracture observation was carried out. The results indicate that the cooling holes have significant effects on the high fatigue life of DD6 single crystal superalloy. The average life of non-hole specimens is four times of that of the three-row holes specimens under the same testing conditions. However, the distribution of cooling film holes has relatively less influence on fatigue life. The fracture of the specimens with non-hole is linear source by SEM analysis, but the cracks are found around the cooling film holes and the fracture of the specimens with single row to three rows is a typical multi-source rupture, and cracks all initiate from near film holes. According to fracture and crystallography theoretical conjecture, the cracks propagate along the {001} slip plane for non-hole, single-row holes and the middle location of the multi-row holes specimens. However, the cracks around the holes grow along the {111} slip plane for upper and lower holes of the specimens with multi-row holes. In addition, the distribution of stress field along cooling holes of four different specimens was analysed by FEM method. The results show that the fracture location and morphology of specimens are consistent well with numerical simulation analysis.

  4. Sulfur isotopic constraints from a single enzyme on the cellular to global sulfur cycles

    Science.gov (United States)

    Sim, M. S.; Adkins, J. F.; Sessions, A. L.; Orphan, V. J.; McGlynn, S.

    2017-12-01

    Since first reported more than a half century ago, sulfur isotope fractionation between sulfate and sulfide has been used as a diagnostic indicator of microbial sulfate reduction, giving added dimensions to the microbial ecological and geochemical studies of the sulfur cycle. A wide range of fractionation has attracted particular attention because it may serve as a potential indicator of environmental or physiological variables such as substrate concentrations or specific respiration rates. In theory, the magnitude of isotope fractionation depends upon the sulfur isotope effect imparted by the involved enzymes and the relative rate of each enzymatic reaction. The former defines the possible range of fractionation quantitatively, while the latter responds to environmental stimuli, providing an underlying rationale for the varying fractionations. The experimental efforts so far have concentrated largely on the latter, the factors affecting the size of fractionation. Recently, however, the direct assessment of intracellular processes emerges as a promising means for the quantitative analysis of microbial sulfur isotope fractionation as a function of environmental or physiological variables. Here, we experimentally determined for the first time the sulfur isotope fractionation during APS reduction, the first reductive step in the dissimilatory sulfate reduction pathway, using the enzyme purified from Desulfovibrio vulgaris Miyazaki. APS reductase carried out the one-step, two-electron reduction of APS to sulfite, without the production of other metabolic intermediates. Nearly identical isotope effects were obtained at two different temperatures, while the rate of APS reduction more than quadrupled with a temperature increase from 20 to 32°C. When placed in context of the linear network model for microbial sulfur isotope fractionation, our finding could provide a new, semi-quantitative constraint on the sulfur cycle at levels from cellular to global.

  5. Substructure based modeling of nickel single crystals cycled at low plastic strain amplitudes

    Science.gov (United States)

    Zhou, Dong

    In this dissertation a meso-scale, substructure-based, composite single crystal model is fully developed from the simple uniaxial model to the 3-D finite element method (FEM) model with explicit substructures and further with substructure evolution parameters, to simulate the completely reversed, strain controlled, low plastic strain amplitude cyclic deformation of nickel single crystals. Rate-dependent viscoplasticity and Armstrong-Frederick type kinematic hardening rules are applied to substructures on slip systems in the model to describe the kinematic hardening behavior of crystals. Three explicit substructure components are assumed in the composite single crystal model, namely "loop patches" and "channels" which are aligned in parallel in a "vein matrix," and persistent slip bands (PSBs) connected in series with the vein matrix. A magnetic domain rotation model is presented to describe the reverse magnetostriction of single crystal nickel. Kinematic hardening parameters are obtained by fitting responses to experimental data in the uniaxial model, and the validity of uniaxial assumption is verified in the 3-D FEM model with explicit substructures. With information gathered from experiments, all control parameters in the model including hardening parameters, volume fraction of loop patches and PSBs, and variation of Young's modulus etc. are correlated to cumulative plastic strain and/or plastic strain amplitude; and the whole cyclic deformation history of single crystal nickel at low plastic strain amplitudes is simulated in the uniaxial model. Then these parameters are implanted in the 3-D FEM model to simulate the formation of PSB bands. A resolved shear stress criterion is set to trigger the formation of PSBs, and stress perturbation in the specimen is obtained by several elements assigned with PSB material properties a priori. Displacement increment, plastic strain amplitude control and overall stress-strain monitor and output are carried out in the user

  6. Investigation of single-cycle separation process based on forward and backward extractions of actinides and fission products

    International Nuclear Information System (INIS)

    Sasaki, Yuji; Tsubata, Yasuhiro; Shirasu, Noriko; Morita, Keisuke; Suzuki, Tomoya

    2015-01-01

    We have been developing a new partitioning method of high-level radioactive waste by the single-cycle extraction process. This process is composed of the extraction of actinides (An) and fission products (FP, e.g., Pd, Ru, Mo and Tc), and mutual separation by reverse extraction. The extractant employed in this process is required to extract soft, hard acid metals and oxonium anions simultaneously. The NTAamide (N,N,N',N',N”,N”,-hexaoctyl-nitrilotriacetamide) is one of the candidate extractants. After the extraction of An and FP, the mutual separation by reverse-extraction should be set up. Distribution ratios of Pd and Ru, which are obtained by NTAamide extraction, can be suppressed by masking agents, thiourea, systeine, diethylenetriamine, and trisaminoethylamine. The masking of Mo can be performed using methylimino-N,N'-diethylacetamide (MIDEA), NTAamide(C2) and iminodimethylphosphoric acid, and Re can be stripped using an aqueous phase with high pH. The information on extraction and masking for these metals will be utilized in the development of the single-cycle process. (author)

  7. Low cycle fatigue properties and microstructure evolution at 760 °C of a single crystal superalloy

    Directory of Open Access Journals (Sweden)

    Zhenxue Shi

    2015-02-01

    Full Text Available Low cycle fatigue (LCF behavior of a single crystal superalloy was investigated at 760 °C. Microstructure evolution and fracture mechanism were studied by scanning electron microscopy (SEM and transmission electron microscopy (TEM, respectively. The results show that the fatigue data fluctuation was small and the fatigue parameters of the alloy had been determined. On increasing the cyclic number, the alloy initially showed slight cyclic softening at the early two or three cycles and slowly hardened to some extent afterwards, then kept stable for the most of the remaining fatigue life. The LCF of the alloy at 760 °C can be attributed to the main elastic damage in fatigue processing. The initiation site of fatigue crack was at or near the surface of the samples. Crack propagated perpendicularly to the loading direction at first and then along {111} octahedral slip planes. The fatigue fracture mechanism was quasi-cleavage fracture. The γ′ phase morphology still maintained cubic shape after fracture. There were a number of slip bands shear the γ′ precipitates and γ matrix near the fracture surface of the specimen. The inhomogeneous deformation microstructure was developed by dislocation motion of cross-slip and a limited γ′ precipitate shearing by slip band, stacking faults or single dislocation was observed.

  8. Processes subject to integrated pollution control. Combustion processes: reheat and heat treatment furnaces 50 MW(th) and over

    International Nuclear Information System (INIS)

    1995-01-01

    This document, part of a series offering guidance on pollution control regulations issued by Her Majesty's Inspectorate of Pollution, focuses on combustion processes involved with reheat and heat treatment furnaces of 50 MW (th) and over. Techniques for controlling releases into air, water and to land are detailed as are the various pollution monitoring strategies. (UK)

  9. Flow-induced vibration and fretting-wear damage in a moisture separator reheater

    International Nuclear Information System (INIS)

    Pettigrew, M.J.; Taylor, C.E.; Fisher, N.J.

    1996-01-01

    Tube failures due to excessive flow-induced vibration were experienced in the tube bundles of moisture separator reheaters in a BWR nuclear station. This paper presents the results of a root cause analysis and covers recommendations for continued operation and for replacement tube bundles. The following tasks are discussed: tube failure analysis; flow velocity distribution calculations; flow-induced vibration analysis with particular emphasis on finned-tubes; fretting-wear testing of a tube and tube-support material combination under simulated operating conditions; field measurements of flow-induced vibration; and development of vibration specifications for replacement tube bundles. The effect of transient operating conditions and of other operational changes such as tube fouling were considered in the analysis. This paper outlines a typical field problem and illustrates the application of flow-induced vibration technology for the solution of a practical problem

  10. Calculation of particle production by Nambu-Goldstone bosons with application to inflation reheating and baryogenesis

    International Nuclear Information System (INIS)

    Dolgov, A.; Freese, K.

    1995-01-01

    A semiclassical calculation of particle production by a scalar field in a potential is performed. We focus on the particular case of production of fermions by a Nambu-Goldstone boson θ. We have derived a (non)local equation of motion for the θ field with the back reaction of the produced particles taken into account. The equation is solved in some special cases, namely, for purely Nambu-Goldstone bosons and for the tilted potential U(θ)∝m 2 θ 2 . Enhanced production of bosons due to parametric resonance is investigated; we argue that the resonance probably disappears when the expansion of the Universe is included. Application of our work on particle production to reheating and an idea for baryogenesis in inflation are mentioned

  11. Iron emission lines from extended x-ray jets in SS 433: reheating of atomic nuclei.

    Science.gov (United States)

    Migliari, Simone; Fender, Rob; Méndez, Mariano

    2002-09-06

    Powerful relativistic jets are among the most ubiquitous and energetic observational consequences of accretion around supermassive black holes in active galactic nuclei and neutron stars and stellar-mass black holes in x-ray binary (XRB) systems. But despite more than three decades of study, the structure and composition of these jets remain unknown. Here we present spatially resolved x-ray spectroscopy of arc second-scale x-ray jets from XRB SS 433 analyzed with the Chandra advanced charge-coupled device imaging spectrometer. These observations reveal evidence for a hot continuum and Doppler-shifted iron emission lines from spatially resolved regions. Apparently, in situ reheating of the baryonic component of the jets takes place in a flow that moves with relativistic bulk velocity even more than 100 days after launch from the binary core.

  12. Performance test of the moisture separator reheaters (MSRs), Using the plant process instrumentation

    International Nuclear Information System (INIS)

    Casado Flores, E.; Bosh Aparicio, J.; Sanz Roman, J.

    1998-01-01

    A reliable test to determine the performance of the MSRs with a degree of reliability of 95% or more must follow the requirements of ASME PTC 12.4 1992. The plant process instrumentation is normally poorer than that required by the code not only in the number of measured parameters but also in accuracy. However, by means of some additional measurements, taken locally, and some appropriate operations, the behaviour of these important equipment items can be determined at the plant. Approximate values for the following parameters are obtained: a) Moisture separation efficiency b) Steam moisture at MSR outlet c) TTDs d) ΔP through the shell of the MSR e) Temperature of the reheated steam at the MSR outlet f) Excess steam flow. (Author)

  13. Automatic Generation Control Study in Two Area Reheat Thermal Power System

    Science.gov (United States)

    Pritam, Anita; Sahu, Sibakanta; Rout, Sushil Dev; Ganthia, Sibani; Prasad Ganthia, Bibhu

    2017-08-01

    Due to industrial pollution our living environment destroyed. An electric grid system has may vital equipment like generator, motor, transformers and loads. There is always be an imbalance between sending end and receiving end system which cause system unstable. So this error and fault causing problem should be solved and corrected as soon as possible else it creates faults and system error and fall of efficiency of the whole power system. The main problem developed from this fault is deviation of frequency cause instability to the power system and may cause permanent damage to the system. Therefore this mechanism studied in this paper make the system stable and balance by regulating frequency at both sending and receiving end power system using automatic generation control using various controllers taking a two area reheat thermal power system into account.

  14. Reheat cracking of austenitic stainless steels - pre-strain effect on intergranular damage

    International Nuclear Information System (INIS)

    Auzoux, Q.

    2004-01-01

    Welding process induces strain in 316 stainless steel affected zones. Their microstructure was reproduce by rolling of three different steels (316L, 316L(N) et 316H). Traction, creep and relaxation tests were performed at 550 deg C and 600 deg C on smooth, notched and pre-cracked specimens. Pre-strain by rolling increases the hardness and the creep resistance because of the high dislocation density but decreases ductility because of the fast development of intergranular damage. This embrittlement leads to crack propagation during relaxation tests on pre-strained steels without distinction in respect to their carbon or nitrogen content. A new intergranular damage model was built using local micro-cracks measurements and finite elements analysis. Pre-strain effect and stress triaxiality ratio effect are reproduced by the modelling so that the reheat cracking risk near welds can now be estimated. (author)

  15. Generation of gravitational waves during early structure formation between cosmic inflation and reheating

    International Nuclear Information System (INIS)

    Jedamzik, Karsten; Lemoine, Martin; Martin, Jérôme

    2010-01-01

    In the pre-reheating era, following cosmic inflation and preceding radiation domination, the energy density may be dominated by an oscillating massive scalar condensate, such as is the case for V = m 2 φ 2 /2 chaotic inflation. We have found in a previous paper that during this period, a wide range of sub-Hubble scale perturbations are subject to a preheating instability, leading to the growth of density perturbations ultimately collapsing to form non-linear structures. We compute here the gravitational wave signal due to these structures in the linear limit and present estimates for emission in the non-linear limit due to various effects: the collapse of halos, the tidal interactions, the evaporation during the conversion of the inflaton condensate into radiation and finally the ensuing turbulent cascades. The gravitational wave signal could be rather large and potentially testable by future detectors

  16. Hypercharged dark matter and direct detection as a probe of reheating.

    Science.gov (United States)

    Feldstein, Brian; Ibe, Masahiro; Yanagida, Tsutomu T

    2014-03-14

    The lack of new physics at the LHC so far weakens the argument for TeV scale thermal dark matter. On the other hand, heavier, nonthermal dark matter is generally difficult to test experimentally. Here we consider the interesting and generic case of hypercharged dark matter, which can allow for heavy dark matter masses without spoiling testability. Planned direct detection experiments will be able to see a signal for masses up to an incredible 1010  GeV, and this can further serve to probe the reheating temperature up to about 109  GeV, as determined by the nonthermal dark matter relic abundance. The Z-mediated nature of the dark matter scattering may be determined in principle by comparing scattering rates on different detector nuclei, which in turn can reveal the dark matter mass. We will discuss the extent to which future experiments may be able to make such a determination.

  17. Reheating and dangerous relics in pre-big-bang string cosmology

    International Nuclear Information System (INIS)

    Buonanno, Alessandra; Lemoine, Martin; Olive, Keith A.

    2000-01-01

    We discuss the mechanism of reheating in pre-big-bang string cosmology and we calculate the amount of moduli and gravitinos produced gravitationally and in scattering processes of the thermal bath. We find that this abundance always exceeds the limits imposed by big-bang nucleosynthesis, and significant entropy production is required. The exact amount of entropy needed depends on the details of the high curvature phase between the dilaton-driven inflationary era and the radiation era. We show that the domination and decay of the zero-mode of a modulus field, which could well be the dilaton, or of axions, suffices to dilute moduli and gravitinos. In this context, baryogenesis can be accommodated in a simple way via the Affleck-Dine mechanism and in some cases the Affleck-Dine condensate could provide both the source of entropy and the baryon asymmetry

  18. CFD analysis of temperature imbalance in superheater/reheater region of tangentially coal-fired boiler

    Science.gov (United States)

    Zainudin, A. F.; Hasini, H.; Fadhil, S. S. A.

    2017-10-01

    This paper presents a CFD analysis of the flow, velocity and temperature distribution in a 700 MW tangentially coal-fired boiler operating in Malaysia. The main objective of the analysis is to gain insights on the occurrences in the boiler so as to understand the inherent steam temperature imbalance problem. The results show that the root cause of the problem comes from the residual swirl in the horizontal pass. The deflection of the residual swirl due to the sudden reduction and expansion of the flow cross-sectional area causes velocity deviation between the left and right side of the boiler. This consequently results in flue gas temperature imbalance which has often caused tube leaks in the superheater/reheater region. Therefore, eliminating the residual swirl or restraining it from being diverted might help to alleviate the problem.

  19. Realistic kinetic loading of the jaw system during single chewing cycles: a finite element study.

    Science.gov (United States)

    Martinez Choy, S E; Lenz, J; Schweizerhof, K; Schmitter, M; Schindler, H J

    2017-05-01

    Although knowledge of short-range kinetic interactions between antagonistic teeth during mastication is of essential importance for ensuring interference-free fixed dental reconstructions, little information is available. In this study, the forces on and displacements of the teeth during kinetic molar biting simulating the power stroke of a chewing cycle were investigated by use of a finite-element model that included all the essential components of the human masticatory system, including an elastic food bolus. We hypothesised that the model can approximate the loading characteristics of the dentition found in previous experimental studies. The simulation was a transient analysis, that is, it considered the dynamic behaviour of the jaw. In particular, the reaction forces on the teeth and joints arose from contact, rather than nodal forces or constraints. To compute displacements of the teeth, the periodontal ligament (PDL) was modelled by use of an Ogden material model calibrated on the basis of results obtained in previous experiments. During the initial holding phase of the power stroke, bite forces were aligned with the roots of the molars until substantial deformation of the bolus occurred. The forces tilted the molars in the bucco-lingual and mesio-distal directions, but as the intrusive force increased the teeth returned to their initial configuration. The Ogden material model used for the PDL enabled accurate prediction of the displacements observed in experimental tests. In conclusion, the comprehensive kinetic finite element model reproduced the kinematic and loading characteristics of previous experimental investigations. © 2017 John Wiley & Sons Ltd.

  20. Zone modelling of the thermal performances of a large-scale bloom reheating furnace

    International Nuclear Information System (INIS)

    Tan, Chee-Keong; Jenkins, Joana; Ward, John; Broughton, Jonathan; Heeley, Andy

    2013-01-01

    This paper describes the development and comparison of a two- (2D) and three-dimensional (3D) mathematical models, based on the zone method of radiation analysis, to simulate the thermal performances of a large bloom reheating furnace. The modelling approach adopted in the current paper differs from previous work since it takes into account the net radiation interchanges between the top and bottom firing sections of the furnace and also allows for enthalpy exchange due to the flows of combustion products between these sections. The models were initially validated at two different furnace throughput rates using experimental and plant's model data supplied by Tata Steel. The results to-date demonstrated that the model predictions are in good agreement with measured heating profiles of the blooms encountered in the actual furnace. It was also found no significant differences between the predictions from the 2D and 3D models. Following the validation, the 2D model was then used to assess the impact of the furnace responses to changing throughput rate. It was found that the potential furnace response to changing throughput rate influences the settling time of the furnace to the next steady state operation. Overall the current work demonstrates the feasibility and practicality of zone modelling and its potential for incorporation into a model based furnace control system. - Highlights: ► 2D and 3D zone models of large-scale bloom reheating furnace. ► The models were validated with experimental and plant model data. ► Examine the transient furnace response to changing the furnace throughput rates. ► No significant differences found between the predictions from the 2D and 3D models.

  1. Observational signatures of the parametric amplification of gravitational waves during reheating after inflation

    Science.gov (United States)

    Kuroyanagi, Sachiko; Lin, Chunshan; Sasaki, Misao; Tsujikawa, Shinji

    2018-01-01

    We study the evolution of gravitational waves (GWs) during and after inflation as well as the resulting observational consequences in a Lorentz-violating massive gravity theory with one scalar (inflaton) and two tensor degrees of freedom. We consider two explicit examples of the tensor mass mg that depends either on the inflaton field ϕ or on its time derivative ϕ ˙, both of which lead to parametric excitations of GWs during reheating after inflation. The first example is Starobinsky's R2 inflation model with a ϕ -dependent mg, and the second is a low energy-scale inflation model with a ϕ ˙-dependent mg. We compute the energy density spectrum ΩGW(k ) today of the GW background. In the Starobinsky's model, we show that the GWs can be amplified up to the detectable ranges of both cosmic microwave background and DECi-hertz Interferometer Gravitational wave Observatory, but the bound from the big bang nucleosynthesis is quite tight to limit the growth. In low-scale inflation with a fast transition to the reheating stage driven by the potential V (ϕ )=M2ϕ2/2 around ϕ ≈Mpl (where Mpl is the reduced Planck mass), we find that the peak position of ΩGW(k ) induced by the parametric resonance can reach the sensitivity region of advanced LIGO for the Hubble parameter of order 1 GeV at the end of inflation. Thus, our massive gravity scenario offers exciting possibilities for probing the physics of primordial GWs at various different frequencies.

  2. A road map for the realization of global-scale thorium breeding fuel cycle by single molten-fluoride flow

    International Nuclear Information System (INIS)

    Furukawa, K.; Arakawa, K.; Erbay, L. B.

    2007-01-01

    For global survival in this century, we urgently need to launch a completely new global nuclear fission industry. To get worldwide public acceptance of nuclear energy, improvements are essential not only on safety, radio-waste management and economy but also especially nuclear proliferation resistance and safeguards. However, such global fission industry cannot replace the present fossil fuel industry in the next 50 years, unless the doubling-time of nuclear energy is less than 10 years, preferably 5-7 years. Such a doubling-time cannot be established by any kind of classical 'Fission Breeding Power Station' concept. We need a symbiotic system which couples fission power reactors with a system which can convert fertile thorium to fissile U-233, such as a spallation or D/T fusion (if and when it becomes available). For such a purpose, THORIMS-NES [Thorium Molten-Salt Nuclear Energy Synergetic System] has been proposed, which is composed of simple thermal fission power stations (FUJI) and fissile producing Accelerator Molten-Salt Breeder (AMSB). Its system functions are very ambitious, delicate and complex, but can be realized in the form of simple hardware applying the multifunctional 'single-phase molten-fluoride' circulation system. This system has no difficulties relating with 'radiation-damage', 'heat-removal' and 'chemical processing' owing to the simple 'idealistic ionic liquid' character. FUJI is size-flexible (economical even in smaller sizes), fuel self-sustaining without any continuous chemical processing and without core-graphite replacement, and AMSB is based on a single-fluid molten-salt target/blanket concept, which solves most engineering difficulties such as radiation-damage, heat-removal etc., except high-current proton accelerator development. Several AMSBs are accommodated in the regional centers (several ten sites in the world) with batch chemical processing plants including radio-waste management. The integrated thorium breeding fuel cycle is

  3. Sorting of cells of the same size, shape, and cell cycle stage for a single cell level assay without staining

    Directory of Open Access Journals (Sweden)

    Yomo Tetsuya

    2006-06-01

    Full Text Available Abstract Background Single-cell level studies are being used increasingly to measure cell properties not directly observable in a cell population. High-performance data acquisition systems for such studies have, by necessity, developed in synchrony. However, improvements in sample purification techniques are also required to reveal new phenomena. Here we assessed a cell sorter as a sample-pretreatment tool for a single-cell level assay. A cell sorter is routinely used for selecting one type of cells from a heterogeneous mixture of cells using specific fluorescence labels. In this case, we wanted to select cells of exactly the same size, shape, and cell-cycle stage from a population, without using a specific fluorescence label. Results We used four light scatter parameters: the peak height and area of the forward scatter (FSheight and FSarea and side scatter (SSheight and SSarea. The rat pheochromocytoma PC12 cell line, a neuronal cell line, was used for all experiments. The living cells concentrated in the high FSarea and middle SSheight/SSarea fractions. Single cells without cell clumps were concentrated in the low SS and middle FS fractions, and in the higher FSheight/FSarea and SSheight/SSarea fractions. The cell populations from these viable, single-cell-rich fractions were divided into twelve subfractions based on their FSarea-SSarea profiles, for more detailed analysis. We found that SSarea was proportional to the cell volume and the FSarea correlated with cell roundness and elongation, as well as with the level of DNA in the cell. To test the method and to characterize the basic properties of the isolated single cells, sorted cells were cultured in separate wells. The cells in all subfractions survived, proliferated and differentiated normally, suggesting that there was no serious damage. The smallest, roundest, and smoothest cells had the highest viability. There was no correlation between proliferation and differentiation. NGF increases

  4. The ATPase cross-bridge cycle of the Kar3 motor domain. Implications for single head motility.

    Science.gov (United States)

    Mackey, Andrew T; Gilbert, Susan P

    2003-02-07

    Kar3 is a minus-end directed microtubule motor involved in meiosis and mitosis in Saccharomyces cerevisae. Unlike Drosophila Ncd, the other well characterized minus-end directed motor that is a homodimer, Kar3 is a heterodimer with a single motor domain and either the associated polypeptides Cik1 or Vik1. Our mechanistic studies with Ncd showed that both motor domains were required for ATP-dependent motor domain detachment from the microtubule. We have initiated a series of experiments to compare the mechanistic requirements for Kar3 motility in direct comparison to Ncd. The results presented here show that the single motor domain of Kar3 (Met(383)-Lys(729)) exhibits characteristics similar to monomeric Ncd. The microtubule-activated steady-state ATPase cycle of Kar3 (k(cat) = 0.5 s(-1)) is limited by ADP release (0.4 s(-1)). Like monomeric Ncd, Kar3 does not readily detach from the microtubule with the addition of MgATP. These results show that the single motor domain of Kar3 is not sufficient for ATP-dependent microtubule dissociation, suggesting that structural elements outside of the catalytic core are required for the cyclic interactions with the microtubule for force generation.

  5. POWER CYCLE AND STRESS ANALYSES FOR HIGH TEMPERATURE GAS-COOLED REACTOR

    International Nuclear Information System (INIS)

    Oh, Chang H; Davis, Cliff; Hawkes, Brian D; Sherman, Steven R

    2007-01-01

    The Department of Energy and the Idaho National Laboratory are developing a Next Generation Nuclear Plant (NGNP) to serve as a demonstration of state-of-the-art nuclear technology. The purpose of the demonstration is two fold (1) efficient low cost energy generation and (2) hydrogen production. Although a next generation plant could be developed as a single-purpose facility, early designs are expected to be dual-purpose. While hydrogen production and advanced energy cycles are still in its early stages of development, research towards coupling a high temperature reactor, electrical generation and hydrogen production is under way. Many aspects of the NGNP must be researched and developed in order to make recommendations on the final design of the plant. Parameters such as working conditions, cycle components, working fluids, and power conversion unit configurations must be understood. Three configurations of the power conversion unit were demonstrated in this study. A three-shaft design with three turbines and four compressors, a combined cycle with a Brayton top cycle and a Rankine bottoming cycle, and a reheated cycle with three stages of reheat were investigated. An intermediate heat transport loop for transporting process heat to a High Temperature Steam Electrolysis (HTSE) hydrogen production plant was used. Helium, CO2, and a 80% nitrogen, 20% helium mixture (by weight) were studied to determine the best working fluid in terms cycle efficiency and development cost. In each of these configurations the relative component size were estimated for the different working fluids. The relative size of the turbomachinery was measured by comparing the power input/output of the component. For heat exchangers the volume was computed and compared. Parametric studies away from the baseline values of the three-shaft and combined cycles were performed to determine the effect of varying conditions in the cycle. This gives some insight into the sensitivity of these cycles to

  6. Physiological responses to incremental, interval, and continuous counterweighted single-leg and double-leg cycling at the same relative intensities.

    Science.gov (United States)

    MacInnis, Martin J; Morris, Nathaniel; Sonne, Michael W; Zuniga, Amanda Farias; Keir, Peter J; Potvin, Jim R; Gibala, Martin J

    2017-07-01

    We compared physiological responses to incremental, interval, and continuous counterweighted single-leg and double-leg cycling at the same relative intensities. The primary hypothesis was that the counterweight method would elicit greater normalized power (i.e., power/active leg), greater electromyography (EMG) responses, and lower cardiorespiratory demand. Graded-exercise tests performed by 12 men (age: 21 ± 2 years; BMI: 24 ± 3 kg/m 2 ) initially established that peak oxygen uptake ([Formula: see text]; 76 ± 8.4%), expired ventilation ([Formula: see text]; 71 ± 6.8%), carbon dioxide production ([Formula: see text]; 71 ± 6.8%), heart rate (HRpeak; 91 ± 5.3%), and power output (PPO; 56 ± 3.6%) were lower during single-leg compared to double-leg cycling (main effect of mode; p cycling were performed at greater absolute power outputs but lower normalized power outputs compared to single-leg cycling (p  0.05), but semitendinosus was activated to a greater extent for single-leg cycling (p = 0.005). Single-leg interval and continuous cycling elicited lower mean [Formula: see text], [Formula: see text], [Formula: see text], HR and ratings of perceived exertion compared to double-leg cycling (p cycling elicits lower cardiorespiratory and perceptual responses than double-leg cycling at greater normalized power outputs.

  7. Effects of single cycle binaural beat duration on auditory evoked potentials.

    Science.gov (United States)

    Mihajloski, Todor; Bohorquez, Jorge; Özdamar, Özcan

    2014-01-01

    Binaural beat (BB) illusions are experienced as continuous central pulsations when two sounds with slightly different frequencies are delivered to each ear. It has been shown that steady-state auditory evoked potentials (AEPs) to BBs can be captured and investigated. The authors recently developed a new method of evoking transient AEPs to binaural beats using frequency modulated stimuli. This methodology was able to create single BBs in predetermined intervals with varying carrier frequencies. This study examines the effects of the BB duration and the frequency modulating component of the stimulus on the binaural beats and their evoked potentials. Normal hearing subjects were tested with a set of four durations (25, 50, 100, and 200 ms) with two stimulation configurations, binaural dichotic (binaural beats) and diotic (frequency modulation). The results obtained from the study showed that out of the given durations, the 100 ms beat, was capable of evoking the largest amplitude responses. The frequency modulation effect showed a decrease in peak amplitudes with increasing beat duration until their complete disappearance at 200 ms. Even though, at 200 ms, the frequency modulation effects were not present, the binaural beats were still perceived and captured as evoked potentials.

  8. Thermal and pseudoelastic cycling in Cu-14.1Al-4.2Ni (wt%) single crystals

    International Nuclear Information System (INIS)

    Gastien, R.; Corbellani, C.E.; Sade, M.; Lovey, F.C.

    2005-01-01

    Thermally and stress induced martensitic transformations between β and a mixture of martensitic structures, β' and γ', were studied in Cu-14.1Al-4.2Ni (wt%) single crystals. In this way information on the relative stability between β' and γ' martensites, compared to the β phase, was obtained. The measurement of electrical resistance as a function of temperature was used to follow the evolution of thermally induced transitions. The stress induced transformations were analyzed in the small temperature range at which the pseudoelastic behavior between β and a mixture of both martensites plays the main role. A clear inhibition of the γ' martensite is detected as the number of cycles increases, no matter which thermodynamic coordinate is varied to induce the phase transition, i.e., temperature or stress. An evaluation of the magnitude of the relative stabilization of the β' martensite compared with γ' was obtained by a suitably designed experiment

  9. Association between ABO blood type and live-birth outcomes in single-embryo transfer cycles.

    Science.gov (United States)

    Pereira, Nigel; Patel, Hency H; Stone, Logan D; Christos, Paul J; Elias, Rony T; Spandorfer, Steven D; Rosenwaks, Zev

    2017-11-01

    To investigate the association between ABO blood type and live-birth outcomes in patients undergoing IVF with day 5 single-embryo transfer (SET). Retrospective cohort study. University-affiliated center. Normal responders, blood type and live birth, while controlling for confounders. Odds ratios (OR) with 95% confidence intervals (CI) for live birth were estimated. A total of 2,329 patients were included. The mean age of the study cohort was 34.6 ± 4.78 years. The distribution of blood types was as follows: A = 897 (38.5%); B = 397 (17.0%); AB = 120 (5.2%); and, O = 1,915 (39.3%) patients. There was no difference in the baseline demographics, ovarian stimulation, or embryo quality parameters between the blood types. The unadjusted ORs for live birth when comparing blood type A (referent) with blood types B, AB, and O were 0.96 (95% CI, 0.6-1.7), 0.72 (95% CI, 0.4-1.2), and 0.96 (95% CI. 0.6-1.7), respectively. The adjusted ORs for live birth remained not significant when comparing blood type A to blood types B, AB, and O individually. No difference in birth weight or gestational age at delivery was noted among the four blood types. Our findings suggest that ABO blood type is not associated with live-birth rate, birth weight, or gestational age at delivery in patients undergoing IVF with day 5 SET. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  10. Single-cell RNA-seq reveals changes in cell cycle and differentiation programs upon aging of hematopoietic stem cells

    Science.gov (United States)

    Kowalczyk, Monika S.; Tirosh, Itay; Heckl, Dirk; Rao, Tata Nageswara; Dixit, Atray; Haas, Brian J.; Schneider, Rebekka K.; Wagers, Amy J.; Ebert, Benjamin L.; Regev, Aviv

    2015-01-01

    Both intrinsic cell state changes and variations in the composition of stem cell populations have been implicated as contributors to aging. We used single-cell RNA-seq to dissect variability in hematopoietic stem cell (HSC) and hematopoietic progenitor cell populations from young and old mice from two strains. We found that cell cycle dominates the variability within each population and that there is a lower frequency of cells in the G1 phase among old compared with young long-term HSCs, suggesting that they traverse through G1 faster. Moreover, transcriptional changes in HSCs during aging are inversely related to those upon HSC differentiation, such that old short-term (ST) HSCs resemble young long-term (LT-HSCs), suggesting that they exist in a less differentiated state. Our results indicate both compositional changes and intrinsic, population-wide changes with age and are consistent with a model where a relationship between cell cycle progression and self-renewal versus differentiation of HSCs is affected by aging and may contribute to the functional decline of old HSCs. PMID:26430063

  11. Analysis of trace inorganic anions in weak acid salts by single pump cycling-column-switching ion chromatography.

    Science.gov (United States)

    Huang, Zhongping; Ni, Chengzhu; Zhu, Zhuyi; Pan, Zaifa; Wang, Lili; Zhu, Yan

    2015-05-01

    The application of ion chromatography with the single pump cycling-column-switching technique was described for the analysis of trace inorganic anions in weak acid salts within a single run. Due to the hydrogen ions provided by an anion suppressor electrolyzing water, weak acid anions could be transformed into weak acids, existing as molecules, after passing through the suppressor. Therefore, an anion suppressor and ion-exclusion column were adopted to achieve on-line matrix elimination of weak acid anions with high concentration for the analysis of trace inorganic anions in weak acid salts. A series of standard solutions consisting of target anions of various concentrations from 0.005 to 10 mg/L were analyzed, with correlation coefficients r ≥ 0.9990. The limits of detection were in the range of 0.67 to 1.51 μg/L, based on the signal-to-noise ratio of 3 and a 25 μL injection volume. Relative standard deviations for retention time, peak area, and peak height were all less than 2.01%. A spiking study was performed with satisfactory recoveries between 90.3 and 104.4% for all anions. The chromatographic system was successfully applied to the analysis of trace inorganic anions in five weak acid salts. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Single-cell transcriptome sequencing reveals that cell division cycle 5-like protein is essential for porcine oocyte maturation.

    Science.gov (United States)

    Liu, Xiao-Man; Wang, Yan-Kui; Liu, Yun-Hua; Yu, Xiao-Xia; Wang, Pei-Chao; Li, Xuan; Du, Zhi-Qiang; Yang, Cai-Xia

    2018-02-02

    The brilliant cresyl blue (BCB) test is used in both basic biological research and assisted reproduction to identify oocytes likely to be developmentally competent. However, the underlying molecular mechanism targeted by the BCB test is still unclear. To explore this question, we first confirmed that BCB-positive porcine oocytes had higher rates of meiotic maturation, better rates of cleavage and development into blastocysts, and lower death rates. Subsequent single-cell transcriptome sequencing on porcine germinal vesicle (GV)-stage oocytes identified 155 genes that were significantly differentially expressed between BCB-negative and BCB-positive oocytes. These included genes such as cdc5l , ldha , spata22 , rgs2 , paip1 , wee1b , and hsp27 , which are enriched in functionally important signaling pathways including cell cycle regulation, oocyte meiosis, spliceosome formation, and nucleotide excision repair. In BCB-positive GV oocytes that additionally had a lower frequency of DNA double-strand breaks, the CDC5L protein was significantly more abundant. cdc5l /CDC5L inhibition by short interference (si)RNA or antibody microinjection significantly impaired porcine oocyte meiotic maturation and subsequent parthenote development. Taken together, our single-oocyte sequencing data point to a potential new role for CDC5L in porcine oocyte meiosis and early embryo development, and supports further analysis of this protein in the context of the BCB test. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  13. Exergy based parametric analysis of a combined reheat regenerative thermal power plant and water–LiBr vapor absorption refrigeration system

    International Nuclear Information System (INIS)

    Gogoi, T.K.; Talukdar, K.

    2014-01-01

    Highlights: • Exergy analysis of a combined power–absorption cooling system is provided. • Exergetic efficiency of the power cycle and absorption cooling system are calculated. • Irreversibility in each component and total system irreversibility are calculated. • Effect of operating parameters on exergetic performance and irreversibility is analyzed. • Optimum operating parameters are identified based on energy and exergy based results. - Abstract: In this paper, exergy analysis of a combined reheat regenerative steam turbine (ST) based power cycle and water–LiBr vapor absorption refrigeration system (VARS) is presented. Exergetic efficiency of the power cycle and VARS, energy utilization factor (EUF) of the combined system (CS) and irreversibility in each system component are calculated. The effect of fuel flow rate, boiler pressure, cooling capacity and VARS components’ temperature on performance, component and total system irreversibility is analyzed. The second law based results indicate optimum performance at 150 bar boiler pressure and VARS generator, condenser, evaporator and absorber temperature of 80 °C, 37.5 °C, 15 °C and 35 °C respectively. The present exergy based results conform well to the first law based results obtained in a previous analysis done on the same combined system. Irreversibility distribution among various power cycle components shows the highest irreversibility in the cooling tower. Irreversibility of the exhaust flue gas leaving the boiler and the boiler are the next major contributors. Among the VARS components, exergy destruction in the generator is the highest followed by irreversibility contribution of the absorber, condenser and the evaporator

  14. Life Cycle Assessment and Costing Methods for Device Procurement: Comparing Reusable and Single-Use Disposable Laryngoscopes.

    Science.gov (United States)

    Sherman, Jodi D; Raibley, Lewis A; Eckelman, Matthew J

    2018-01-09

    Traditional medical device procurement criteria include efficacy and safety, ease of use and handling, and procurement costs. However, little information is available about life cycle environmental impacts of the production, use, and disposal of medical devices, or about costs incurred after purchase. Reusable and disposable laryngoscopes are of current interest to anesthesiologists. Facing mounting pressure to quickly meet or exceed conflicting infection prevention guidelines and oversight body recommendations, many institutions may be electively switching to single-use disposable (SUD) rigid laryngoscopes or overcleaning reusables, potentially increasing both costs and waste generation. This study provides quantitative comparisons of environmental impacts and total cost of ownership among laryngoscope options, which can aid procurement decision making to benefit facilities and public health. We describe cradle-to-grave life cycle assessment (LCA) and life cycle costing (LCC) methods and apply these to reusable and SUD metal and plastic laryngoscope handles and tongue blade alternatives at Yale-New Haven Hospital (YNHH). The US Environmental Protection Agency's Tool for the Reduction and Assessment of Chemical and other environmental Impacts (TRACI) life cycle impact assessment method was used to model environmental impacts of greenhouse gases and other pollutant emissions. The SUD plastic handle generates an estimated 16-18 times more life cycle carbon dioxide equivalents (CO2-eq) than traditional low-level disinfection of the reusable steel handle. The SUD plastic tongue blade generates an estimated 5-6 times more CO2-eq than the reusable steel blade treated with high-level disinfection. SUD metal components generated much higher emissions than all alternatives. Both the SUD handle and SUD blade increased life cycle costs compared to the various reusable cleaning scenarios at YNHH. When extrapolated over 1 year (60,000 intubations), estimated costs increased

  15. The Analysis of Initial Parameters of Steam in the Combined-Cycle Plant with High Temperature Gas Turbine

    OpenAIRE

    Uvarov, Artem; Antonova, Aleksandra Mikhailovna; Vorobiev, Aleksandr Vladimirovich

    2015-01-01

    Presents the results of studying the influence of initial steam parameters on the thermal efficiency of double-circuit combined-cycle plant based on a powerful high-temperature gas turbines of the last generation. The advantages of double-circuit combined-cycle plant without reheat in comparison with more complex schemes. Found optimal thermal efficiency values of initial parameters of steam.

  16. Effect of menstrual cycle on frequency of alveolar osteitis in women undergoing surgical removal of mandibular third molar: a single-blind randomized clinical trial.

    Science.gov (United States)

    Eshghpour, Majid; Rezaei, Naser Mohammadzadeh; Nejat, AmirHossein

    2013-09-01

    To measure the association between the menstrual cycle and the frequency of alveolar osteitis (AO). In a study with a single-blind design, patients with bilateral impacted third molar teeth underwent randomized surgical extraction: one tooth during the menstrual period and one during the middle of the cycle. The postoperative examiner was unaware of the menstrual cycle status of the patients. The predictor variable was the timing of the menstrual cycle and was grouped as mid-cycle and menstrual period. The outcome variable was AO, which was measured (without knowledge of the menstrual cycle timing) at 2 to 7 days postoperatively. Other study variables included oral contraceptive (OC) use, smoking status, irrigation used during surgery, extraction difficulty, surgeon experience, number of local anesthetic cartridges used, and patient age. Appropriate bi- and multivariate statistics were computed, and the level of statistical significance was set at P cycle than during the menstrual period inboth the OC users and nonusers (P menstrual period (P > .05). According to the results of the present study, the menstrual cycle could be a determinant risk factor in the frequency of AO. We recommend that elective procedures be performed during the menstrual period in both OC users and nonusers to eliminate the effect of cycle-related hormonal changes on the development of AO. Copyright © 2013 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  17. Phase quantification during pseudoelastic cycling of Cu-13.1Al-4.0Ni (wt.%) single-crystal shape memory alloys using neutron diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Kannarpady, Ganesh K. [Smart Materials and MEMS Laboratory, Department of Applied Science, University of Arkansas at Little Rock, 2801 South University, ETAS 575, Little Rock, AR 72204-1099 (United States); Bhattacharyya, Abhijit [Smart Materials and MEMS Laboratory, Department of Applied Science, University of Arkansas at Little Rock, 2801 South University, ETAS 575, Little Rock, AR 72204-1099 (United States)], E-mail: axbhattachar@ualr.edu; Wolverton, Mike [Smart Materials and MEMS Laboratory, Department of Applied Science, University of Arkansas at Little Rock, 2801 South University, ETAS 575, Little Rock, AR 72204-1099 (United States); Brown, Donald W. [Materials Science and Technology Division, Los Alamos National Laboratory, NM 87545 (United States); Vogel, Sven C. [Los Alamos Neutron Science Center, Los Alamos National Laboratory, NM 87545 (United States); Pulnev, Sergei [Department of Solid State Physics, Ioffe Physico-Technical Institute, St. Petersburg (Russian Federation)

    2008-10-15

    This paper reports on the pseudoelastic, isothermal mechanical cycling of copper-aluminium-nickel single-crystals. It was found that stress-free transformation temperatures at the end of 1000 stress cycles did not change, whereas the transformation stresses decreased by about 10%; otherwise, the overall strain of 7% imposed during a loading cycle was completely recovered at the end of 1000 cycles. Non-contact multi-video extensometry uncovered a significant spatial non-uniformity in the maximum strains attained in different sections of the wire. At the end of the 1000th cycle, the top and bottom sections demonstrated very similar maximum strains while the midsection demonstrated lower strain. Phase quantification of the midsection of the wire using neutron diffraction demonstrated an increase in the stabilization of austenite from 0% in the first cycle to about 60% in the 1000th cycle. The specific nature of the tests required by neutron diffraction also uncovered a creep-like response of the SMA. Preliminary investigation suggests that this 'pseudo-creep' is due to the motion of phase fronts during the phase transformation. Neutron diffraction has also confirmed that while the single crystallinity of the SMA is excellent at 175 deg. C, there is a spread in orientation of the cubic phase at 200 deg. C with respect to the axis of the wire that is estimated at 2.17 deg. This spread disappears/reappears on mechanical loading/unloading, but decreases permanently on cyclic loading.

  18. Reheating, thermalization and non-thermal gravitino production in MSSM inflation

    Energy Technology Data Exchange (ETDEWEB)

    Ferrantelli, Andrea [Tallinn University of Technology, Faculty of Civil Engineering, Tallinn (Estonia)

    2017-10-15

    In the framework of MSSM inflation, matter and gravitino production are here investigated through the decay of the fields which are coupled to the udd inflaton, a gauge-invariant combination of squarks. After the end of inflation, the flat direction oscillates about the minimum of its potential, losing at each oscillation about 56% of its energy into bursts of gauge/gaugino and scalar quanta when crossing the origin. These particles then acquire a large inflaton VEV-induced mass and decay perturbatively into the MSSM quanta and gravitinos, transferring the inflaton energy very efficiently via instant preheating. Regarding thermalization, we show that the MSSM degrees of freedom thermalize very quickly, yet not immediately by virtue of the large vacuum expectation value of the inflaton, which breaks the SU(3){sub C} x U(1){sub Y} symmetry into a residual U(1). The energy transfer to the MSSM quanta is very efficient, since full thermalization is achieved after only O(40) complete oscillations. The udd inflaton thus provides an extremely efficient reheating of the Universe, with a temperature T{sub reh} = O(10{sup 8} GeV), which allows for instance several mechanisms of baryogenesis. We also compute the gravitino number density from the perturbative decay of the flat direction and of the SUSY multiplet. We find that the gravitinos are produced in negligible amount and satisfy cosmological bounds such as the Big Bang nucleosynthesis (BBN) and dark matter (DM) constraints. (orig.)

  19. Exergy Analysis of a Subcritical Reheat Steam Power Plant with Regression Modeling and Optimization

    Directory of Open Access Journals (Sweden)

    MUHIB ALI RAJPER

    2016-07-01

    Full Text Available In this paper, exergy analysis of a 210 MW SPP (Steam Power Plant is performed. Firstly, the plant is modeled and validated, followed by a parametric study to show the effects of various operating parameters on the performance parameters. The net power output, energy efficiency, and exergy efficiency are taken as the performance parameters, while the condenser pressure, main steam pressure, bled steam pressures, main steam temperature, and reheat steam temperature isnominated as the operating parameters. Moreover, multiple polynomial regression models are developed to correlate each performance parameter with the operating parameters. The performance is then optimizedby using Direct-searchmethod. According to the results, the net power output, energy efficiency, and exergy efficiency are calculated as 186.5 MW, 31.37 and 30.41%, respectively under normal operating conditions as a base case. The condenser is a major contributor towards the energy loss, followed by the boiler, whereas the highest irreversibilities occur in the boiler and turbine. According to the parametric study, variation in the operating parameters greatly influences the performance parameters. The regression models have appeared to be a good estimator of the performance parameters. The optimum net power output, energy efficiency and exergy efficiency are obtained as 227.6 MW, 37.4 and 36.4, respectively, which have been calculated along with optimal values of selected operating parameters.

  20. Relativistic electron beams driven by single-cycle laser pulses at kHz repetition rate (Conference Presentation)

    Science.gov (United States)

    Faure, Jérôme; Guénot, Diego; Gustas, Dominykas; Vernier, Aline; Beaurepaire, Benoît; Böhle, Frederik; López-Martens, Rodrigo; Lifschitz, Agustin

    2017-05-01

    Laser-plasma accelerators are usually driven by 100-TW class laser systems with rather low repetition rates. However, recent years have seen the emergence of laser-plasma accelerators operating with kHz lasers and energies lower than 10 mJ. The high repetition-rate is particularly interesting for applications requiring high stability and high signal-to-noise ratio but lower energy electrons. For example, our group recently demonstrated that kHz laser-driven electron beams could be used to capture ultrafast structural dynamics in Silicon nano-membranes via electron diffraction with picosecond resolution. In these first experiments, electrons were injected in the density gradients located at the plasma exit, resulting in rather low energies in the 100 keV range. The electrons being nonrelativistic, the bunch duration quickly becomes picosecond long. Relativistic energies are required to mitigate space charge effects and maintain femtosecond bunches. In this paper, we will show very recent results where electrons are accelerated in laser-driven wakefields to relativistic energies, reaching up to 5 MeV at kHz repetition rate. The electron energy was increased by nearly two orders of magnitude by using single-cycle laser pulses of 3.5 fs, with only 2.5 mJ of energy. Using such short pulses of light allowed us to resonantly excite high amplitude and nonlinear plasma waves at high plasma density, ne=1.5-2×1020 cm-3, in a regime close to the blow-out regime. Electrons had a peaked distribution around 5 MeV, with a relative energy spread of 30 %. Charges in the 100's fC/shot and up to pC/shot where measured depending on plasma density. The electron beam was fairly collimated, 20 mrad divergence at Full Width Half Maximum. The results show remarkable stability of the beam parameters in terms of beam pointing and electron distribution. 3D PIC simulations reproduce the results very well and indicate that electrons are injected by the ionization of Nitrogen atoms, N5+ to N6

  1. Quantitative consideration for the tempering effect during multi-pass thermal cycle in HAZ of low-alloy steel

    International Nuclear Information System (INIS)

    Yu, Lina; Nakabayashi, Yuma; Saida, Kazuyoshi; Mochizuki, Masahito; Nishimoto, Kazutoshi; Kameyama, Masashi; Hirano, Shinro; Chigusa, Naoki

    2011-01-01

    A new Thermal Cycle Tempering Parameter (TCTP) to deal with the tempering effect during multi-pass thermal cycles has been proposed by extending Larson-Miller parameter (LMP). Experimental result revealed that the hardness in synthetic HAZ of the low alloy steel subjected to multi tempering thermal cycles has a good linear relationship with TCTP. By using this relationship, the hardness of the low-alloy steel reheated with tempering thermal cycles can be predicted when the original hardness is known. (author)

  2. Embrittlement of Intercritically Reheated Coarse Grain Heat-Affected Zone of ASTM4130 Steel

    Science.gov (United States)

    Li, Liying; Han, Tao; Han, Bin

    2018-04-01

    In this investigation, a thermal welding simulation technique was used to investigate the microstructures and mechanical properties of the intercritically reheated coarse grain heat-affected zone (IR CGHAZ) of ASTM4130 steel. The effect of post weld heat treatment (PWHT) on the toughness of IR CGHAZ was also analyzed. The toughness of IR CGHAZ was measured by means of Charpy impact, and it is found that IR CGHAZ has the lowest toughness which is much lower than that of the base metal regardless of whether PWHT is applied or not. The as-welded IR CGHAZ is mainly composed of ferrite, martensite, and many blocky M-A constituents distributing along grain boundaries and subgrain boundaries in a near-connected network. Also, the prior austenite grains are still as coarse as those in the coarse grain heat-affected zone (CGHAZ). The presence of the blocky M-A constituents and the coarsened austenite grains result in the toughness deterioration of the as-welded IR CGHAZ. Most of the blocky M-A constituents are decomposed to granular bainite due to the effect of the PWHT. However, PWHT cannot refine the prior austenite grains. Thus, the low toughness of IR CGHAZ after PWHT can be attributed to two factors, i.e., the coarsened austenite grains, and the presence of the remaining M-A constituents and granular bainite, which are located at grain boundaries and subgrain boundaries in a near-connected network. The absorbed energy of the IR CGHAZ was increased by about 3.75 times, which means that the PWHT can effectively improve the toughness but it cannot be recovered to the level of base metal.

  3. A CHANDRA OBSERVATION OF 3C 288-REHEATING THE COOL CORE OF A 3 keV CLUSTER FROM A NUCLEAR OUTBURST at z = 0.246

    International Nuclear Information System (INIS)

    Lal, D. V.; Kraft, R. P.; Forman, W. R.; Jones, C.; Nulsen, P. E. J.; Evans, D. A.; Lee, J. C.; Hardcastle, M. J.; Croston, J. H.

    2010-01-01

    We present results from a 42 ks Chandra/ACIS-S observation of the transitional FR I/FR II radio galaxy 3C 288 at z = 0.246. We detect ∼3 keV gas extending to a radius of ∼0.5 Mpc with a 0.5-2.0 keV luminosity of 6.6 x 10 43 erg s -1 , implying that 3C 288 lies at the center of a poor cluster. We find multiple surface brightness discontinuities in the gas indicative of either a shock driven by the inflation of the radio lobes or a recent merger event. The temperature across the discontinuities is roughly constant with no signature of a cool core, thus disfavoring either the merger cold front or sloshing scenarios. We argue therefore that the discontinuities are shocks due to the supersonic inflation of the radio lobes. If they are shocks, the energy of the outburst is ∼10 60 erg, or roughly 30% of the thermal energy of the gas within the radius of the shock, assuming that the shocks are part of a front produced by a single outburst. The cooling time of the gas is ∼10 8 yr, so that the energy deposited by the nuclear outburst could have reheated and efficiently disrupted a cool core.

  4. Patient and cycle characteristics predicting high pregnancy rates with single-embryo transfer: an analysis of the Society for Assisted Reproductive Technology outcomes between 2004 and 2013.

    Science.gov (United States)

    Mersereau, Jennifer; Stanhiser, Jamie; Coddington, Charles; Jones, Tiffany; Luke, Barbara; Brown, Morton B

    2017-11-01

    To analyze factors associated with high live birth rate and low multiple birth rate in fresh and frozen-thawed assisted reproductive technology (ART) cycles. Retrospective cohort analysis. Not applicable. The study population included 181,523 women undergoing in vitro fertilization with autologous fresh first cycles, 27,033 with fresh first oocyte donor cycles, 37,658 with fresh second cycles, and 35,446 with frozen-thawed second cycles. None. Live birth rate and multiple birth rate after single-embryo transfer (SET) and double embryo transfer (DET) were measured, in addition to cycle characteristics. In patients with favorable prognostic factors, including younger maternal age, transfer of a blastocyst, and additional embryos cryopreserved, the gain in the live birth rate from SET to DET was approximately 10%-15%; however, the multiple birth rate increased from approximately 2% to greater than 49% in both autologous and donor fresh and frozen-thawed transfer cycles. This study reports a 10%-15% reduction in live birth rate and a 47% decrement in multiple birth rate with SET compared with DET in the setting of favorable patient prognostic factors. Our findings present an opportunity to increase the rate of SET across the United States and thereby reduce the multiple birth rate and its associated poor perinatal outcomes with assisted reproductive technology pregnancies. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  5. Energy Conversion Advanced Heat Transport Loop and Power Cycle

    Energy Technology Data Exchange (ETDEWEB)

    Oh, C. H.

    2006-08-01

    The Department of Energy and the Idaho National Laboratory are developing a Next Generation Nuclear Plant (NGNP) to serve as a demonstration of state-of-the-art nuclear technology. The purpose of the demonstration is two fold 1) efficient low cost energy generation and 2) hydrogen production. Although a next generation plant could be developed as a single-purpose facility, early designs are expected to be dual-purpose. While hydrogen production and advanced energy cycles are still in its early stages of development, research towards coupling a high temperature reactor, electrical generation and hydrogen production is under way. Many aspects of the NGNP must be researched and developed in order to make recommendations on the final design of the plant. Parameters such as working conditions, cycle components, working fluids, and power conversion unit configurations must be understood. Three configurations of the power conversion unit were demonstrated in this study. A three-shaft design with 3 turbines and 4 compressors, a combined cycle with a Brayton top cycle and a Rankine bottoming cycle, and a reheated cycle with 3 stages of reheat were investigated. An intermediate heat transport loop for transporting process heat to a High Temperature Steam Electrolysis (HTSE) hydrogen production plant was used. Helium, CO2, and an 80% nitrogen, 20% helium mixture (by weight) were studied to determine the best working fluid in terms cycle efficiency and development cost. In each of these configurations the relative component size were estimated for the different working fluids. The relative size of the turbomachinery was measured by comparing the power input/output of the component. For heat exchangers the volume was computed and compared. Parametric studies away from the baseline values of the three-shaft and combined cycles were performed to determine the effect of varying conditions in the cycle. This gives some insight into the sensitivity of these cycles to various

  6. Thermodynamic evaluation of the Kalina split-cycle concepts for waste heat recovery applications

    International Nuclear Information System (INIS)

    Nguyen, Tuong-Van; Knudsen, Thomas; Larsen, Ulrik; Haglind, Fredrik

    2014-01-01

    The Kalina split-cycle is a thermodynamic process for converting thermal energy into electrical power. It uses an ammonia–water mixture as a working fluid (like a conventional Kalina cycle) and has a varying ammonia concentration during the pre-heating and evaporation steps. This second feature results in an improved match between the heat source and working fluid temperature profiles, decreasing the entropy generation in the heat recovery system. The present work compares the thermodynamic performance of this power cycle with the conventional Kalina process, and investigates the impact of varying boundary conditions by conducting an exergy analysis. The design parameters of each configuration were determined by performing a multi-variable optimisation. The results indicate that the Kalina split-cycle with reheat presents an exergetic efficiency by 2.8% points higher than a reference Kalina cycle with reheat, and by 4.3% points without reheat. The cycle efficiency varies by 14% points for a variation of the exhaust gas temperature of 100 °C, and by 1% point for a cold water temperature variation of 30 °C. This analysis also pinpoints the large irreversibilities in the low-pressure turbine and condenser, and indicates a reduction of the exergy destruction by about 23% in the heat recovery system compared to the baseline cycle. - Highlights: • The thermodynamic performance of the Kalina split-cycle is assessed. • The Kalina split-cycle is compared to the Kalina cycle, with and without reheat. • An exergy analysis is performed to evaluate its thermodynamic performance. • The impact of varying boundary conditions is investigated. • The Kalina split-cycle displays high exergetic efficiency for low- and medium-temperature applications

  7. Beat-to-Beat Variation in Periodicity of Local Calcium Releases Contributes to Intrinsic Variations of Spontaneous Cycle Length in Isolated Single Sinoatrial Node Cells.

    Directory of Open Access Journals (Sweden)

    Oliver Monfredi

    Full Text Available Spontaneous, submembrane local Ca(2+ releases (LCRs generated by the sarcoplasmic reticulum in sinoatrial nodal cells, the cells of the primary cardiac pacemaker, activate inward Na(+/Ca(2+-exchange current to accelerate the diastolic depolarization rate, and therefore to impact on cycle length. Since LCRs are generated by Ca(2+ release channel (i.e. ryanodine receptor openings, they exhibit a degree of stochastic behavior, manifested as notable cycle-to-cycle variations in the time of their occurrence.The present study tested whether variation in LCR periodicity contributes to intrinsic (beat-to-beat cycle length variability in single sinoatrial nodal cells.We imaged single rabbit sinoatrial nodal cells using a 2D-camera to capture LCRs over the entire cell, and, in selected cells, simultaneously measured action potentials by perforated patch clamp.LCRs begin to occur on the descending part of the action potential-induced whole-cell Ca(2+ transient, at about the time of the maximum diastolic potential. Shortly after the maximum diastolic potential (mean 54±7.7 ms, n = 14, the ensemble of waxing LCR activity converts the decay of the global Ca(2+ transient into a rise, resulting in a late, whole-cell diastolic Ca(2+ elevation, accompanied by a notable acceleration in diastolic depolarization rate. On average, cells (n = 9 generate 13.2±3.7 LCRs per cycle (mean±SEM, varying in size (7.1±4.2 µm and duration (44.2±27.1 ms, with both size and duration being greater for later-occurring LCRs. While the timing of each LCR occurrence also varies, the LCR period (i.e. the time from the preceding Ca(2+ transient peak to an LCR's subsequent occurrence averaged for all LCRs in a given cycle closely predicts the time of occurrence of the next action potential, i.e. the cycle length.Intrinsic cycle length variability in single sinoatrial nodal cells is linked to beat-to-beat variations in the average period of individual LCRs each cycle.

  8. Low-cycle fatigue and damage of an uncoated and coated single crystal nickel-base superalloy SCB

    International Nuclear Information System (INIS)

    Stekovic, S.; Ericsson, T.

    2007-01-01

    This paper presents low-cycle fatigue (LCF) behaviour and damage mechanisms of uncoated and coated specimens of a single crystal nickel-base superalloy SCB tested at 500 C and 900 C. Four coatings were deposited on the base material, an overlay coating AMDRY997, a platinum-modified aluminide diffusion coating RT22 and two innovative coatings called IC1 and IC3 with a NiW diffusion barrier in the interface. AMDRY997 and RT22 were used as reference coatings. The LCF tests were performed at three strain amplitudes, 1.0, 1.2 and 1.4%, with R = -1, in laboratory air and without any dwell time. The LCF life of the specimens is determined by crack initiation and propagation. Crack data are presented for different classes of crack size in the form of crack density, that is, the number of cracks normalised to the investigated interface length. Micrographs of damage of the coatings are also shown. The effect of the coatings on the LCF life of the superalloy was dependent on the test temperature and deposited coating. At 500 C all coatings had a detrimental effect on the LCF life of the superalloy. At 900 C both AMDRY997 and IC1 prolonged the fatigue life of the superalloy by factors ranging between 1.5 and 4 while RT22 and IC3 shortened the life of the coating-substrate system. Specimens coated with RT22 exhibited generally more damage than other tested coatings at 900 C. Most of the cracks observed initiated at the coating surface and a majority were arrested in the interdiffusion zone between the base material and the coating. No topologically close-packed phases were found. Delamination was only found in AMDRY997 at higher strains. Surface roughness or rumpling was found in the overlay coating AMDRY997 with some cracks initiating from the rumples. The failure morphology at 900 C reflected the role of oxidation in the fatigue life, the crack initiation and propagation of the coated specimens. The wake of the cracks grown into the substrate was severely oxidised leading to

  9. Application of a high-repetition-rate laser diagnostic system for single-cycle-resolved imaging in internal combustion engines.

    Science.gov (United States)

    Hult, Johan; Richter, Mattias; Nygren, Jenny; Aldén, Marcus; Hultqvist, Anders; Christensen, Magnus; Johansson, Bengt

    2002-08-20

    High-repetition-rate laser-induced fluorescence measurements of fuel and OH concentrations in internal combustion engines are demonstrated. Series of as many as eight fluorescence images, with a temporal resolution ranging from 10 micros to 1 ms, are acquired within one engine cycle. A multiple-laser system in combination with a multiple-CCD camera is used for cycle-resolved imaging in spark-ignition, direct-injection stratified-charge, and homogeneous-charge compression-ignition engines. The recorded data reveal unique information on cycle-to-cycle variations in fuel transport and combustion. Moreover, the imaging system in combination with a scanning mirror is used to perform instantaneous three-dimensional fuel-concentration measurements.

  10. Fast power cycle for fusion reactors

    International Nuclear Information System (INIS)

    Powell, J.; Fillo, J.; Makowitz, H.

    1978-01-01

    The unique, deep penetration capability of 14 MeV neutrons produced in DT fusion reactions allows the generation of very high temperature working fluid temperatures in a thermal power cycle. In the FAST (Fusion Augmented Steam Turbine) power cycle steam is directly superheated by the high temperature ceramic refractory interior of the blanket, after being generated by heat extracted from the relatively cool blanket structure. The steam is then passed to a high temperature gas turbine for power generation. Cycle studies have been carried out for a range of turbine inlet temperatures [1600 0 F to 3000 0 F (870 to 1650 0 C)], number of reheats, turbine mechanical efficiency, recuperator effectiveness, and system pressure losses. Gross cycle efficiency is projected to be in the range of 55 to 60%, (fusion energy to electric power), depending on parameters selected. Turbine inlet temperatures above 2000 0 F, while they do increase efficiency somewhat, are not necessarily for high cycle efficiency

  11. Design and analysis of helium Brayton power cycles for HiPER reactor

    Energy Technology Data Exchange (ETDEWEB)

    Sánchez, Consuelo, E-mail: csanchez@ind.uned.es [Dpto. Ingeniería Energética UNED, Madrid (Spain); Juárez, Rafael; Sanz, Javier [Dpto. Ingeniería Energética UNED, Madrid (Spain); Instituto de Fusión Nuclear/UPM, Madrid (Spain); Perlado, Manuel [Instituto de Fusión Nuclear/UPM, Madrid (Spain)

    2013-10-15

    Highlights: ► A helium Brayton cycle has been designed integrating the two energy sources of HiPER. ► The Brayton cycle has intercooling stages and a recovery process. ► The low temperature of HiPER heat sources results in low cycle efficiency (35.2%). ► Two inter-cooling stages and a reheating process increases efficiency to over 37%. ► Helium Brayton cycles are to be considered as candidates for HiPER power cycles. -- Abstract: Helium Brayton cycles have been studied as power cycles for both fission and fusion reactors obtaining high thermal efficiency. This paper studies several technological schemes of helium Brayton cycles applied for the HiPER reactor proposal. Since HiPER integrates technologies available at short term, its working conditions results in a very low maximum temperature of the energy sources, something that limits the thermal performance of the cycle. The aim of this work is to analyze the potential of the helium Brayton cycles as power cycles for HiPER. Several helium Brayton cycle configurations have been investigated with the purpose of raising the cycle thermal efficiency under the working conditions of HiPER. The effects of inter-cooling and reheating have specifically been studied. Sensitivity analyses of the key cycle parameters and component performances on the maximum thermal efficiency have also been carried out. The addition of several inter-cooling stages in a helium Brayton cycle has allowed obtaining a maximum thermal efficiency of over 36%, and the inclusion of a reheating process may also yield an added increase of nearly 1 percentage point to reach 37%. These results confirm that helium Brayton cycles are to be considered among the power cycle candidates for HiPER.

  12. Cytotoxicity and cell-cycle effects of paclitaxel when used as a single agent and in combination with ionizing radiation

    International Nuclear Information System (INIS)

    Gupta, Nalin; Hu, Lily J.; Deen, Dennis F.

    1997-01-01

    Purpose: This study aimed to determine the extent of paclitaxel-induced cytotoxicity and cell-cycle perturbations when used alone and in combination with radiation in human glioma cells. Methods and Materials: The effect of paclitaxel alone on three human glioma cells lines--SF-126, U-87 MG, and U-251 MG--was assessed after 24, 48, 72, or 96 h treatment. For experiments in combination with radiation, cells were exposed to either a long (48-h) or short (8-h) duration of paclitaxel treatment prior to irradiation. Cell survival was determined by clonogenic assay. Cell cycle perturbations were assessed by using flow cytometry to measure the proportion of cells in G 1 , S, and G 2 /M phases. Results: When cells were treated with paclitaxel alone for ≥24 h, cytotoxicity increased up to a threshold dose, after which it plateaued. When treatment duration was ≤24 h, cytotoxicity was appreciably greater in U-251 MG cells than in SF-126 and U-87 MG cells. After 24 h of paclitaxel treatment, cells in plateau phase growth had increased survival compared to cells in log phase growth. In contrast, after 8 h paclitaxel treatment, mitotic cells had reduced survival compared to cells from an asynchronous population. Cell-cycle perturbations were consistent with the presence of a mitotic block after paclitaxel treatment, although changes in other cell-cycle phase fractions varied among cell lines. For experiments in combination with radiation, cytotoxicity was increased when cells were irradiated after 48 h of paclitaxel treatment but not after 8 h of treatment. Conclusion: The duration of paclitaxel treatment and the location of cells in the cell cycle modify the degree of radiation cytotoxicity. The mechanisms of paclitaxel cytotoxicity are likely to be multifactorial because varying effects are seen in different cell lines. Furthermore, it is clear that simply increasing the number of cells in G 2 /M is insufficient in itself to increase the response of cells to radiation

  13. Improvements in steam cycle thermal power stations

    International Nuclear Information System (INIS)

    1973-01-01

    The invention provides improvements in steam cycle thermal power stations. The power station adapted to supply a network with variable requirements, is according provided with a heat accumulator. A feed water re-heater using steam taken in the steam generator, is mounted downstream of the water-station. This arrangement permits to substantially increase the temperature of the water admitted into the steam generator and allows the accumulator to restore the heat accumulated at a higher-rate, at peak periods. This can be applied to power stations, the basic thermal source of which is adapted only to moderate working conditions [fr

  14. Improvements in steam cycle thermal power stations

    International Nuclear Information System (INIS)

    1973-01-01

    The invention relates to improvements in steam-cycle thermal power stations. In a heat storage and recovery installation, two exchangers provide a heat transfert between the working fluid and a thermofluid, in a direction or the other according as heat must be stored or recovered. In the case of heat storage, the exchanger makes use of live steam as heating fluid. In the case of heat recovery, the steam generator feed-water is heated in the exchangers at the expanse of the thermo-fluid, then in a water reheater using live steam as heating fluid. This can be applied to power stations feeding variable consumption networks [fr

  15. Study on cycle-slip detection and repair methods for a single dual-frequency global positioning system (GPS receiver

    Directory of Open Access Journals (Sweden)

    La Van Hieu

    Full Text Available In this work, we assessed the performance of the cycle-slip detection methods: Turbo Edit (TE, Melbourne-Wübbena wide-lane ambiguity (MWWL and forward and backward moving window averaging (FBMWA. The TE and MWWL methods were combined with ionospheric total electron content rate (TECR, and the FBMWA with second-order time-difference phase ionosphere residual (STPIR and TECR. Under different scenarios, 10 Global Positioning System (GPS datasets were used to assess the performance of the methods for cycle-slip detection. The MWWL-TECR delivered the best performance in detecting cycle-slips for 1 s data. The relative comparisons show that the FBMWA-TECR method performed slightly better than its original version, FBMWA-STPIR, detecting 100% and 73%, respectively. For data with a sample rate of 5 s, the FBMWA-TECR performed better than MWWL-TECR. However, the FBMWA is suitable only for post-processing, which refers to applications where the data are processed after the fact.

  16. A σ-T diagram analysis regarding the γ' inhibition in β ↔ β' + γ' cycling in CuAlNi single crystals

    International Nuclear Information System (INIS)

    Gastien, R.; Corbellani, C.E.; Sade, M.; Lovey, F.C.

    2006-01-01

    An effect of inhibition of the γ' martensitic structure in thermal and pseudoelastic β ↔ β' + γ' cycling in CuAlNi single crystals was reported previously [Gastien R, Corbellani CE, Alvarez Villar HN, Sade M, Lovey FC. Mater Sci Eng A 2003;349:191], and an experiment to determine the new thermodynamic parameters to obtain the stress-induced γ' structure was performed [Gastien R, Corbellani CE, Sade M, Lovey FC. Acta Mater 2005;53:1685]. In this paper, a thermodynamic analysis of this effect using σ-T diagrams is proposed, in order to obtain a proper estimation of the energy involved in the inhibition process for pseudoelastic β ↔ β' + γ' cycling

  17. Computer code for single-point thermodynamic analysis of hydrogen/oxygen expander-cycle rocket engines

    Science.gov (United States)

    Glassman, Arthur J.; Jones, Scott M.

    1991-01-01

    This analysis and this computer code apply to full, split, and dual expander cycles. Heat regeneration from the turbine exhaust to the pump exhaust is allowed. The combustion process is modeled as one of chemical equilibrium in an infinite-area or a finite-area combustor. Gas composition in the nozzle may be either equilibrium or frozen during expansion. This report, which serves as a users guide for the computer code, describes the system, the analysis methodology, and the program input and output. Sample calculations are included to show effects of key variables such as nozzle area ratio and oxidizer-to-fuel mass ratio.

  18. Advantages of a single-cycle production assay to study cell culture-adaptive mutations of hepatitis C virus

    DEFF Research Database (Denmark)

    Russell, Rodney S; Meunier, Jean-Christophe; Takikawa, Shingo

    2008-01-01

    mutations that were selected during serial passage in Huh-7.5 cells were studied. Recombinant genomes containing all five mutations produced 3-4 logs more infectious virions than did wild type. Neither a coding mutation in NS5A nor a silent mutation in E2 was adaptive, whereas coding mutations in E2, p7......The JFH1 strain of hepatitis C virus (HCV) is unique among HCV isolates, in that the wild-type virus can traverse the entire replication cycle in cultured cells. However, without adaptive mutations, only low levels of infectious virus are produced. In the present study, the effects of five...

  19. Influence of the reheat temperature on the efficiency of the wet-steam turbines of thermal power plants that operate under variable conditions

    Science.gov (United States)

    Tarelin, A. A.

    2017-04-01

    A brief analysis of the existing methods for controlling the operating conditions of the turbine units that operate at variable loads is presented. In practice, the outdated rule of operation is most frequently used that states that the higher the parameters of the live and reheat steam and the lower the condenser pressure are, the higher is the efficiency of the turbine unit. However, in the technical literature, there is sufficiently substantiated evidence that this approach is not always correct, especially under low loads. This applies to both the regulation of the initial and final pressure and reheat temperature t r. In the article, particular stress is laid on the controllable parameter t r, the effect of which in the operational practices, according to the results of the analysis, is underestimated. The causes are considered that constrain more effective use of reheat temperature t r as a process variable. The results of field trials to investigate the influence of t r on the efficiency of turbine units of various capacities, viz., of 210, 250, 300, and 325 MW, during operation at varying loads are presented. It is shown that a decrease in t r to an optimal value of 10-30°C, depending on the load and the condenser pressure, increases the thermal efficiency by 1-2%. The following general pattern has been set: the lower the load, the lower the optimal reheat temperature. The main causes and factors that result in more efficient use of the heat phase transition in the steam path of the low-pressure cylinder and increased efficiency of the unit under rational choice of the reheat temperature are studied.

  20. Cumulative results including obstetrical and neonatal outcome of fresh and frozen-thawed cycles in elective single versus double fresh embryo transfers.

    Science.gov (United States)

    Fauque, Patricia; Jouannet, Pierre; Davy, Céline; Guibert, Juliette; Viallon, Vivian; Epelboin, Sylvie; Kunstmann, Jean-Marie; Patrat, Catherine

    2010-08-01

    To assess the efficacy of elective single embryo transfer (e-SET) compared to a double embryo transfer (DET) in a selected population including obstetrical and neonatal outcome of fresh and frozen-thawed cycles. Prospective nonrandomized study. Department of reproductive medicine. Elective single embryo transfer was proposed to women 0.05). Twin delivery rate was significantly different between the two groups (3.5% versus 37.5% respectively, P<0.05). Neonatal outcome in twins resulting from IVF-ICSI was found to be poorer than in singletons, considering the mean gestational age, mode of delivery, birthweight, and risk of neonatal intensive care unit admission for the infants. In a selected population, the elective transfer of one embryo with high implantation potential helped to avoid twin pregnancies without decreasing delivery rate. Copyright (c) 2010 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  1. HiHiMap: single-cell quantitation of histones and histone posttranslational modifications across the cell cycle by high-throughput imaging.

    Science.gov (United States)

    Zane, Linda; Chapus, Fleur; Pegoraro, Gianluca; Misteli, Tom

    2017-08-15

    We describe Hi gh-throughput Hi stone Map ping (HiHiMap), a high-throughput imaging method to measure histones and histone posttranslational modifications (PTMs) in single cells. HiHiMap uses imaging-based quantification of DNA and cyclin A to stage individual cells in the cell cycle to determine the levels of histones or histone PTMs in each stage of the cell cycle. As proof of principle, we apply HiHiMap to measure the level of 21 core histones, histone variants, and PTMs in primary, immortalized, and transformed cells. We identify several histone modifications associated with oncogenic transformation. HiHiMap allows the rapid, high-throughput study of histones and histone PTMs across the cell cycle and the study of subpopulations of cells. © 2017 Zane et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  2. Effects of single dose GnRH agonist as luteal support on pregnancy outcome in frozen-thawed embryo transfer cycles: an RCT

    Directory of Open Access Journals (Sweden)

    Robab Davar

    2015-08-01

    Full Text Available Background: There is no doubt that luteal phase support is essential to enhance the reproductive outcome in IVF cycles. In addition to progesterone and human chorionic gonadotropin, several studies have described GnRH agonists as luteal phase support to improve implantation rate, pregnancy rate and live birth rate, whereas other studies showed dissimilar conclusions. All of these studies have been done in fresh IVF cycles. Objective: To determine whether an additional GnRH agonist administered at the time of implantation for luteal phase support in frozen-thawed embryo transfer (FET improves the embryo developmental potential. Materials and Methods: This is a prospective controlled trial study in 200 FET cycles, patients were randomized on the day of embryo transfer into group 1 (n=100 to whom a single dose of GnRH agonist (0.1 mg triptorelin was administered three days after transfer and group 2 (n=100, who did not receive agonist. Both groups received daily vaginal progesterone suppositories plus estradiol valerate 6 mg daily. Primary outcome measure was clinical pregnancy rate. Secondary outcome measures were implantation rate, chemical, ongoing pregnancy rate and abortion rate. Results: A total of 200 FET cycles were analyzed. Demographic data and embryo quality were comparable between two groups. No statistically significant difference in clinical and ongoing pregnancy rates was observed between the two groups (26% versus 21%, p=0.40 and 21% versus 17%, p=0.37, respectively. Conclusion: Administration of a subcutaneous GnRH agonist at the time of implantation does not increase clinical or ongoing pregnancy.

  3. Scanning Electron Microscopy Analysis of the Adaptation of Single-Unit Screw-Retained Computer-Aided Design/Computer-Aided Manufacture Abutments After Mechanical Cycling.

    Science.gov (United States)

    Markarian, Roberto Adrian; Galles, Deborah Pedroso; Gomes França, Fabiana Mantovani

    To measure the microgap between dental implants and custom abutments fabricated using different computer-aided design/computer-aided manufacture (CAD/CAM) methods before and after mechanical cycling. CAD software (Dental System, 3Shape) was used to design a custom abutment for a single-unit, screw-retained crown compatible with a 4.1-mm external hexagon dental implant. The resulting stereolithography file was sent for manufacturing using four CAD/CAM methods (n = 40): milling and sintering of zirconium dioxide (ZO group), cobalt-chromium (Co-Cr) sintered via selective laser melting (SLM group), fully sintered machined Co-Cr alloy (MM group), and machined and sintered agglutinated Co-Cr alloy powder (AM group). Prefabricated titanium abutments (TI group) were used as controls. Each abutment was placed on a dental implant measuring 4.1× 11 mm (SA411, SIN) inserted into an aluminum block. Measurements were taken using scanning electron microscopy (SEM) (×4,000) on four regions of the implant-abutment interface (IAI) and at a relative distance of 90 degrees from each other. The specimens were mechanically aged (1 million cycles, 2 Hz, 100 N, 37°C) and the IAI width was measured again using the same approach. Data were analyzed using two-way analysis of variance, followed by the Tukey test. After mechanical cycling, the best adaptation results were obtained from the TI (2.29 ± 1.13 μm), AM (3.58 ± 1.80 μm), and MM (1.89 ± 0.98 μm) groups. A significantly worse adaptation outcome was observed for the SLM (18.40 ± 20.78 μm) and ZO (10.42 ± 0.80 μm) groups. Mechanical cycling had a marked effect only on the AM specimens, which significantly increased the microgap at the IAI. Custom abutments fabricated using fully sintered machined Co-Cr alloy and machined and sintered agglutinated Co-Cr alloy powder demonstrated the best adaptation results at the IAI, similar to those obtained with commercial prefabricated titanium abutments after mechanical cycling. The

  4. Systems Level Dissection of Anaerobic Methane Cycling: Quantitative Measurements of Single Cell Ecophysiology, Genetic Mechanisms, and Microbial Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Orphan, Victoria [California Inst. of Technology (CalTech), Pasadena, CA (United States); Tyson, Gene [University of Queensland, Brisbane Australia; Meile, Christof [University of Georgia, Athens, Georgia; McGlynn, Shawn [California Inst. of Technology (CalTech), Pasadena, CA (United States); Yu, Hang [California Inst. of Technology (CalTech), Pasadena, CA (United States); Chadwick, Grayson [California Inst. of Technology (CalTech), Pasadena, CA (United States); Marlow, Jeffrey [California Inst. of Technology (CalTech), Pasadena, CA (United States); Trembath-Reichert, Elizabeth [California Inst. of Technology (CalTech), Pasadena, CA (United States); Dekas, Anne [California Inst. of Technology (CalTech), Pasadena, CA (United States); Hettich, Robert [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Pan, Chongle [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ellisman, Mark [University of California San Diego; Hatzenpichler, Roland [California Inst. of Technology (CalTech), Pasadena, CA (United States); Skennerton, Connor [California Inst. of Technology (CalTech), Pasadena, CA (United States); Scheller, Silvan [California Inst. of Technology (CalTech), Pasadena, CA (United States)

    2017-12-25

    The global biological CH4 cycle is largely controlled through coordinated and often intimate microbial interactions between archaea and bacteria, the majority of which are still unknown or have been only cursorily identified. Members of the methanotrophic archaea, aka ‘ANME’, are believed to play a major role in the cycling of methane in anoxic environments coupled to sulfate, nitrate, and possibly iron and manganese oxides, frequently forming diverse physical and metabolic partnerships with a range of bacteria. The thermodynamic challenges overcome by the ANME and their bacterial partners and corresponding slow rates of growth are common characteristics in anaerobic ecosystems, and, in stark contrast to most cultured microorganisms, this type of energy and resource limited microbial lifestyle is likely the norm in the environment. While we have gained an in-depth systems level understanding of fast-growing, energy-replete microorganisms, comparatively little is known about the dynamics of cell respiration, growth, protein turnover, gene expression, and energy storage in the slow-growing microbial majority. These fundamental properties, combined with the observed metabolic and symbiotic versatility of methanotrophic ANME, make these cooperative microbial systems a relevant (albeit challenging) system to study and for which to develop and optimize culture-independent methodologies, which enable a systems-level understanding of microbial interactions and metabolic networks. We used an integrative systems biology approach to study anaerobic sediment microcosms and methane-oxidizing bioreactors and expanded our understanding of the methanotrophic ANME archaea, their interactions with physically-associated bacteria, ecophysiological characteristics, and underlying genetic basis for cooperative microbial methane-oxidation linked with different terminal electron acceptors. Our approach is inherently multi-disciplinary and multi-scaled, combining transcriptional and

  5. Single-cell transcriptomic reconstruction reveals cell cycle and multi-lineage differentiation defects in Bcl11a-deficient hematopoietic stem cells.

    Science.gov (United States)

    Tsang, Jason C H; Yu, Yong; Burke, Shannon; Buettner, Florian; Wang, Cui; Kolodziejczyk, Aleksandra A; Teichmann, Sarah A; Lu, Liming; Liu, Pentao

    2015-09-21

    Hematopoietic stem cells (HSCs) are a rare cell type with the ability of long-term self-renewal and multipotency to reconstitute all blood lineages. HSCs are typically purified from the bone marrow using cell surface markers. Recent studies have identified significant cellular heterogeneities in the HSC compartment with subsets of HSCs displaying lineage bias. We previously discovered that the transcription factor Bcl11a has critical functions in the lymphoid development of the HSC compartment. In this report, we employ single-cell transcriptomic analysis to dissect the molecular heterogeneities in HSCs. We profile the transcriptomes of 180 highly purified HSCs (Bcl11a (+/+) and Bcl11a (-/-)). Detailed analysis of the RNA-seq data identifies cell cycle activity as the major source of transcriptomic variation in the HSC compartment, which allows reconstruction of HSC cell cycle progression in silico. Single-cell RNA-seq profiling of Bcl11a (-/-) HSCs reveals abnormal proliferative phenotypes. Analysis of lineage gene expression suggests that the Bcl11a (-/-) HSCs are constituted of two distinct myeloerythroid-restricted subpopulations. Remarkably, similar myeloid-restricted cells could also be detected in the wild-type HSC compartment, suggesting selective elimination of lymphoid-competent HSCs after Bcl11a deletion. These defects are experimentally validated in serial transplantation experiments where Bcl11a (-/-) HSCs are myeloerythroid-restricted and defective in self-renewal. Our study demonstrates the power of single-cell transcriptomics in dissecting cellular process and lineage heterogeneities in stem cell compartments, and further reveals the molecular and cellular defects in the Bcl11a-deficient HSC compartment.

  6. Characteristics of the two-way memory effect induced by thermomechanical cycling in Cu-Zn-Al single crystals

    International Nuclear Information System (INIS)

    Amengual, A.; Cesari, E.; Pons, J.

    1995-01-01

    Some results concerning the two-way shape memory effect induced by thermomechanical training in Cu-Zn-Al single crystals with e/a=1.48 are presented. The repetitive training procedure consists of a thermal induced transformation with the specimen submitted to a constant tensile stress and a subsequent reverse transformation without any external applied stress. The induced two-way shape memory effect is characterized by measuring the efficiency and the strength, cooling the sample under a compressive external stress. Some specimens are conveniently thermally treated in order to introduce dispersions of small γ-phase precipitates (size about 10 nm) inside the β matrix. The characteristics of the two-way memory effect shown by the material containing precipitates and the precipitate-free alloy are compared. (orig.)

  7. Hormonal, Metabolic and Cardiorespiratory Responses of Young and Adult Athletes to a Single Session of High Intensity Cycle Exercise

    OpenAIRE

    Engel, Florian; Härtel, Sascha; Wagner, Matthias Oliver; Strahler, Jana; Bös, Klaus; Sperlich, Billy

    2014-01-01

    This study aimed to determine the effects of a single High Intensity Interval Training (HIIT) session on salivary cortisol (SC) levels, physiological responses and performance in trained boys and men. Twenty-three boys (11.5±0.8 years) and 25 men (29.7±4.6 years) performed HIIT (four consecutive Wingate Anaerobic Tests). SC in boys and men increased after HIIT from 5.55±3.3 nmol/l to 15.13±9.7 nmol/l (+173%) and from 7.07±4.7 nmol/l to 19.19±12.7 nmol/l (+171%), respectively (p

  8. Single and Combined Effects of Beetroot Crystals and Sodium Bicarbonate on 4-km Cycling Time Trial Performance.

    Science.gov (United States)

    Callahan, Marcus J; Parr, Evelyn B; Hawley, John A; Burke, Louise M

    2017-06-01

    When ingested alone, beetroot juice and sodium bicarbonate are ergogenic for high-intensity exercise performance. This study sought to determine the independent and combined effects of these supplements. Eight endurance trained (VO 2 max 65 mL·kg·min -1 ) male cyclists completed four × 4-km time trials (TT) in a doubleblind Latin square design supplementing with beetroot crystals (BC) for 3 days (15 g·day -1 + 15 g 1 h before TT, containing 300 mg nitrate per 15 g), bicarbonate (Bi 0.3 g·kg -1 body mass [BM] in 5 doses every 15 min from 2.5 h before TT); BC+Bi or placebo (PLA). Subjects completed TTs on a Velotron cycle ergometer under standardized laboratory conditions. Plasma nitrite concentrations were significantly elevated only in the BC+Bi trial before the TT (1520 ± 786 nmol·L -1 ) compared with baseline (665 ± 535 nmol·L -1 , p = .02) and the Bi and PLA conditions (Bi: 593 ± 203 nmol·L -1 , p .05). Blood bicarbonate concentrations were increased in the BC+Bi and Bi trials before the TT (BC+Bi: 30.9 ± 2.8 mmol·L -1 ; Bi: 31.7 ± 1.1 mmol·L -1 ). There were no differences in mean power output (386-394 W) or the time taken to complete the TT (335.8-338.1 s) between any conditions. Under the conditions of this study, supplementation was not ergogenic for 4-km TT performance.

  9. Not all twins are monozygotic after elective single embryo transfer: analysis of 32,600 elective single embryo transfer cycles as reported to the Society for Assisted Reproductive Technology.

    Science.gov (United States)

    Vega, Mario; Zaghi, Sahar; Buyuk, Erkan; Jindal, Sangita

    2018-01-01

    To study the incidence and risk factors of multiple pregnancies after elective single ET. Historic cohort. Not applicable. Women single ET entered in the SART CORS database from 2010 to 2013. Not applicable. Rate of sex discordant pregnancies. Rate of same sex pregnancies and risk factors for both same sex and sex discordant pregnancies. A total of 32,600 cycles were reported to SART CORS during this time period. There were 15,143 pregnancies from which 14,888 were singletons (98.3%), 23 sex discordant (0.15%) multiple pregnancies, 226 (1.5%) sex concordant multiple pregnancies, and 6 (0.01%) pregnancies without sex information. When Weinberg's differential rule was applied, the rate of dizygotic pregnancies was calculated to be 18%. Unexplained infertility was found to be the biggest risk factor for sex discordant multiple pregnancies (adjusted odds ratio 4.33, 95% confidence interval 1.4-13.1), followed by elevated body mass index (BMI). The only risk factor found for sex concordant pregnancies was undergoing a fresh transfer (adjusted odds ratio 1.4, 95% confidence interval 1.02-1.95). Elective single ET improves, but does not completely eliminate the risk of multiple pregnancies. Patients should be counseled that there might be up to a ∼2% risk of multiple pregnancies, of which up to 18% can be dizygotic. Patients with elevated BMI and unexplained fertility may be at higher risk for sex discordant multiple pregnancies and patients undergoing fresh cycles may be at higher risk for sex concordant multiple pregnancies. Copyright © 2017 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  10. A randomized assessor-blind trial comparing highly purified hMG and recombinant FSH in a GnRH antagonist cycle with compulsory single-blastocyst transfer

    DEFF Research Database (Denmark)

    Devroey, Paul; Pellicer, Antonio; Nyboe Andersen, Anders

    2012-01-01

    OBJECTIVE: To compare the efficacy and safety of highly purified menotropin (hphMG) and recombinant FSH (rFSH) for controlled ovarian stimulation in a GnRH antagonist cycle with compulsory single-blastocyst transfer. DESIGN: Randomized, open-label, assessor-blind, parallel groups, multicenter......, noninferiority trial. SETTING: Twenty-five infertility centers in seven countries. PATIENT(S): Seven hundred forty-nine women. INTERVENTION(S): Controlled ovarian stimulation with hphMG or rFSH in a GnRH antagonist cycle with compulsory single-blastocyst transfer on day 5 in one fresh or subsequent frozen......MG versus 27% with rFSH for the per-protocol (PP) population and 29% versus 27% for the intention-to-treat (ITT) population. Noninferiority of hphMG compared to rFSH was established. Considering frozen cycles initiated within 1 year, the cumulative live birth rate for a single stimulation cycle was 40...

  11. Scaling submillimeter single-cycle transients toward megavolts per centimeter field strength via optical rectification in the organic crystal OH1.

    Science.gov (United States)

    Ruchert, Clemens; Vicario, Carlo; Hauri, Christoph P

    2012-03-01

    We present the generation of high-power single-cycle terahertz (THz) pulses in the organic salt crystal 2-[3-(4-hydroxystyryl)-5.5-dimethylcyclohex-2-enylidene]malononitrile or OH1. Broadband THz radiation with a central frequency of 1.5 THz (λ(c)=200 μm) and high electric field strength of 440 kV/cm is produced by optical rectification driven by the signal of a powerful femtosecond optical parametric amplifier. A 1.5% pump to THz energy conversion efficiency is reported, and pulse energy stability better than 1% RMS is achieved. An approach toward the realization of higher field strength is discussed. © 2012 Optical Society of America

  12. Direct measuring of single-cycle mid-IR light bullets path length in LiF by the laser coloration method

    Science.gov (United States)

    Chekalin, Sergey; Kompanets, Victor; Kuznetsov, Andrey; Dormidonov, Alexander; Kandidov, Valerii

    2017-10-01

    A colour-centre structure formed in a LiF crystal under filamentation of a femtosecond mid-IR laser pulse with a power slightly exceeding the critical power for self-focusing has been experimentally and theoretically investigated. A single-cycle light bullet was recorded for the first time by observation of strictly periodic oscillations for the density of the color centers induced in an isotropic LiF crystal under filamentation of a laser beam with a wavelength tuned in the range from 2600 to 3900 nm, which is due to the periodic change in the light field amplitude in the light bullet formed under filamentation under propagation in dispersive medium. The light bullet path length was not more than one millimeter.

  13. Direct measuring of single-cycle mid-IR light bullets path length in LiF by the laser coloration method

    Directory of Open Access Journals (Sweden)

    Chekalin Sergey

    2017-01-01

    Full Text Available A colour-centre structure formed in a LiF crystal under filamentation of a femtosecond mid-IR laser pulse with a power slightly exceeding the critical power for self-focusing has been experimentally and theoretically investigated. A single-cycle light bullet was recorded for the first time by observation of strictly periodic oscillations for the density of the color centers induced in an isotropic LiF crystal under filamentation of a laser beam with a wavelength tuned in the range from 2600 to 3900 nm, which is due to the periodic change in the light field amplitude in the light bullet formed under filamentation under propagation in dispersive medium. The light bullet path length was not more than one millimeter.

  14. Structural Changes in Cooked Rice Treated with Cooling-Reheating Process and Coconut Milk Addition as Observed With FT-IR and 13C NMR

    Directory of Open Access Journals (Sweden)

    Nuri Arum Anugrahati

    2017-03-01

    Full Text Available The molecular structural changes of food could be observed by the technique of FT-IR and 13C NMR spectroscopy. This research was aimed to study the structural changes in cooked rice treated with cooling-reheating process and coconut milk addition using FT-IR and 13C NMR. It was found that the cooling-reheating process and addition of coconut milk cause several structural changes of cooked rice. The IR analysis showed the bands at 3,400, 2,900, 1,018 and 856 cm-1 changed due to the retrogradation during cooling process. The spectrum of 13C NMR showed the change of peaks at 100.28 and 100.10 ppm. These changes may be related to the addition of coconut milk during rice cooking.

  15. Root cause analysis of oxide scale forming and shedding in high temperature reheater of a 200MW super high pressure boiler

    Science.gov (United States)

    Bo, Jiang; Hao, Weidong; Hu, Zhihong; Liu, Fuguo

    2015-12-01

    In order to solve the problem of over temperature tube-burst caused by oxide scale shedding and blocking tubes of high temperature reheater of a 200MW super high pressure power plant boiler, this paper expounds the mechanism of scale forming and shedding, and analyzes the probable causes of the tube-burst failure. The results show that the root cause of scale forming is that greater steam extraction flow after reforming of the second extraction leads to less steam flow into reheater, which causes over temperature to some of the heated tubes; and the root cause of scale shedding is that long term operation in AGC-R mode brings about great fluctuations of unit load, steam temperature and pressure, accelerating scale shedding. In conclusion, preventive measures are drawn up considering the operation mode of the unit.

  16. Energy, Exergy and Economic Evaluation Comparison of Small-Scale Single and Dual Pressure Organic Rankine Cycles Integrated with Low-Grade Heat Sources

    Directory of Open Access Journals (Sweden)

    Armando Fontalvo

    2017-09-01

    Full Text Available Low-grade heat sources such as solar thermal, geothermal, exhaust gases and industrial waste heat are suitable alternatives for power generation which can be exploited by means of small-scale Organic Rankine Cycle (ORC. This paper combines thermodynamic optimization and economic analysis to assess the performance of single and dual pressure ORC operating with different organic fluids and targeting small-scale applications. Maximum power output is lower than 45 KW while the temperature of the heat source varies in the range 100–200 °C. The studied working fluids, namely R1234yf, R1234ze(E and R1234ze(Z, are selected based on environmental, safety and thermal performance criteria. Levelized Cost of Electricity (LCOE and Specific Investment Cost (SIC for two operation conditions are presented: maximum power output and maximum thermal efficiency. Results showed that R1234ze(Z achieves the highest net power output (up to 44 kW when net power output is optimized. Regenerative ORC achieves the highest performance when thermal efficiency is optimized (up to 18%. Simple ORC is the most cost-effective among the studied cycle configurations, requiring a selling price of energy of 0.3 USD/kWh to obtain a payback period of 8 years. According to SIC results, the working fluid R1234ze(Z exhibits great potential for simple ORC when compared to conventional R245fa.

  17. Retrofitted Solar Domestic Hot Water Systems for Swedish Single-Family Houses—Evaluation of a Prototype and Life-Cycle Cost Analysis

    Directory of Open Access Journals (Sweden)

    Luis Ricardo Bernardo

    2016-11-01

    Full Text Available According to recent technology road maps, system cost reductions and development of standardised plug-and-function systems are some of the most important goals for solar heating technology development. Retrofitting hot water boilers in single-family houses when installing solar collectors has the potential to significantly reduce both material and installation costs. Previous studies have investigated such retrofitting, using theoretical simulations and laboratory tests, but no actual installations were made and tested in practice. This article describes the installation, measured performance and cost effectiveness of a retrofitting solution that converts existing domestic hot water heaters to a solar domestic hot water system. The measured performance is characterised by the monthly and annual solar fractions. The cost effectiveness is evaluated by a life-cycle cost analysis, comparing the retrofitted system to a conventional solar domestic hot water system and the case without any solar heating system. Measurements showed that approximately 50% of the 5000 kWh/year of domestic hot water consumption was saved by the retrofitted system in south Sweden. Such savings are in agreement with previous estimations and are comparable to the energy savings when using a conventional solar domestic hot water system. The life-cycle cost analysis showed that, according to the assumptions and given climate, the return on investment of the retrofitted system is approximately 17 years, while a conventional system does not reach profitability during its lifetime of 25 years.

  18. Effect of heating/reheating of fats/oils, as used by Asian Indians, on trans fatty acid formation.

    Science.gov (United States)

    Bhardwaj, Swati; Passi, Santosh Jain; Misra, Anoop; Pant, Kamal K; Anwar, Khalid; Pandey, R M; Kardam, Vikas

    2016-12-01

    Heating/frying and reuse of edible fats/oils induces chemical changes such as formation of trans fatty acids (TFAs). The aim of this study was to investigate the effect of heating/frying on formation of TFAs in fats/oils. Using gas chromatography with flame ionisation detector, TFA was estimated in six commonly used fat/oils in India (refined soybean oil, groundnut oil, olive oil, rapeseed oil, clarified butter, partially hydrogenated vegetable oil), before and after subjecting them to heating/frying at 180°C and 220°C. All six fats/oils subjected to heating/frying demonstrated an increase in TFAs (poils (after subjecting to heating/reheating) ranged between 2.30±0.89g/100g and 4.5±1.43g/100g; amongst edible fats it ranged between 2.60±0.38g/100g and 5.96±1.94g/100g. There were no significant differences between the two treatment groups (heating and frying; p=0.892). Considering the undesirable health effects of TFA, appropriate guidelines for heating/re-frying of edible fats/oils by Asian Indians should be devised. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Effect of Primary Recrystallized Microstructure and Nitriding on Secondary Recrystallization in Grain Oriented Silicon Steel by Low Temperature Slab Reheating

    Directory of Open Access Journals (Sweden)

    LIU Gong-tao

    2018-01-01

    Full Text Available Different primary recrystallized grain sizes were obtained by controlling decarburization process in grain oriented silicon steel produced by low temperature slab reheating technique. The effect of primary grain size on secondary recrystallization and magnetic properties was studied. The appropriate nitrogen content after nitriding was explored in case of very large primary grain size, and the effect of {411}〈148〉 primary recrystallized texture on the abnormal growth behavior was discussed. The results show that an increase in average primary grain size from 10μm to 15μm leads to an increase of secondary recrystallization temperature and a sharper Goss texture with higher magnetic permeability, in the condition of a very large average primary grain size of 28μm, the suitable amount of nitrogen increases to about 6×10-4. The {411}〈148〉 oriented grains in primary recrystallized microstructure can easily grow into larger sizes due to their size advantage, and thus hinder the abnormal growth of secondary grains, moreover, the hindering effect is more pronounced in the abnormal growth of Brass-oriented grains due to their misorientation with low migration rate other than Goss grains.

  20. Effects of Re-heating Tissue Samples to Core Body Temperature on High-Velocity Ballistic Projectile-tissue Interactions.

    Science.gov (United States)

    Humphrey, Caitlin; Henneberg, Maciej; Wachsberger, Christian; Maiden, Nicholas; Kumaratilake, Jaliya

    2017-11-01

    Damage produced by high-speed projectiles on organic tissue will depend on the physical properties of the tissues. Conditioning organic tissue samples to human core body temperature (37°C) prior to conducting ballistic experiments enables their behavior to closely mimic that of living tissues. To minimize autolytic changes after death, the tissues are refrigerated soon after their removal from the body and re-heated to 37°C prior to testing. This research investigates whether heating 50-mm-cube samples of porcine liver, kidney, and heart to 37°C for varying durations (maximum 7 h) can affect the penetration response of a high-speed, steel sphere projectile. Longer conditioning times for heart and liver resulted in a slight loss of velocity/energy of the projectile, but the reverse effect occurred for the kidney. Possible reasons for these trends include autolytic changes causing softening (heart and liver) and dehydration causing an increase in density (kidney). © 2017 American Academy of Forensic Sciences.

  1. Single-Cell Genome and Group-Specific dsrAB Sequencing Implicate Marine Members of the Class Dehalococcoidia (Phylum Chloroflexi) in Sulfur Cycling

    DEFF Research Database (Denmark)

    Wasmund, Kenneth; Cooper, Myriel; Schreiber, Lars

    2016-01-01

    The marine subsurface sediment biosphere is widely inhabited by bacteria affiliated with the class Dehalococcoidia (DEH), phylum Chloroflexi, and yet little is known regarding their metabolisms. In this report, genomic content from a single DEH cell (DEH-C11) with a 16S rRNA gene that was affilia......The marine subsurface sediment biosphere is widely inhabited by bacteria affiliated with the class Dehalococcoidia (DEH), phylum Chloroflexi, and yet little is known regarding their metabolisms. In this report, genomic content from a single DEH cell (DEH-C11) with a 16S rRNA gene...... that was affiliated with a diverse cluster of 16S rRNA gene sequences prevalent in marine sediments was obtained from sediments of Aarhus Bay, Denmark. The distinctive gene content of this cell suggests metabolic characteristics that differ from those of known DEH and Chloroflexi. The presence of genes encoding...... dissimilatory sulfite reductase (Dsr) suggests that DEH could respire oxidized sulfur compounds, although Chloroflexi have never been implicated in this mode of sulfur cycling. Using long-range PCR assays targeting DEH dsr loci, dsrAB genes were amplified and sequenced from various marine sediments. Many...

  2. Modular approach to analysis of chemically recuperated gas turbine cycles

    Energy Technology Data Exchange (ETDEWEB)

    Carcasci, C.; Facchini, B. [University of Florence, `Sergio Stecco` (Italy). Dept. of Energy Engineering; Harvey, S. [Chalmers Institute of Technology, Goeteberg (Sweden). Dept. of Heat and Power Technology

    1998-12-31

    Current research programmes such as the CAGT programme investigate the opportunity for advanced power generation cycles based on state-of-the-art aeroderivative gas turbine technology. Such cycles would be primarily aimed at intermediate duty applications. Compared to industrial gas turbines, aeroderivatives offer high simple cycle efficiency, and the capability to start quickly and frequently without a significant maintenance cost penalty. A key element for high system performance is the development of improved heat recovery systems, leading to advanced cycles such as the humid air turbine (HAT) cycle, the chemically recuperated gas turbine (CRGT) cycle and the Kalina combined cycle. When used in combination with advanced technologies and components, screening studies conducted by research programmes such as the CAGT programme predict that such advanced cycles could theoretically lead to net cycle efficiencies exceeding 60%. In this paper, the authors present the application of the modular approach to cycle simulation and performance predictions of CRGT cycles. The paper first presents the modular simulation code concept and the main characteristics of CRGT cycles. The paper next discusses the development of the methane-steam reformer unit model used for the simulations. The modular code is then used to compute performance characteristics of a simple CRGT cycle and a reheat CRGT cycle, both based on the General Electric LM6000 aeroderivative gas turbine. (author)

  3. Advanced gas turbine cycles a brief review of power generation thermodynamics

    CERN Document Server

    Horlock, JH

    2003-01-01

    Primarily this book describes the thermodynamics of gas turbine cycles. The search for high gas turbine efficiency has produced many variations on the simple ""open circuit"" plant, involving the use of heat exchangers, reheating and intercooling, water and steam injection, cogeneration and combined cycle plants. These are described fully in the text. A review of recent proposals for a number of novel gas turbine cycles is also included. In the past few years work has been directed towards developing gas turbines which produce less carbon dioxide, or plants from which the CO2 can be d

  4. Dependence of cosmological energy-density irregularities on the shape of the scalar-field potential during inflation and ''reheating''

    International Nuclear Information System (INIS)

    Ratra, B.

    1991-01-01

    Estimates for the baryon-dominated epoch form of the large-scale adiabatic energy-density irregularities generated during an early scalar-field-dominated inflation epoch, in simple inflation-modified hot-big-bang models, are compared to the widely used approximate general expression, which is proportional to the large-scale, gauge-invariant part of H 2 left-angle φφ * right-angle/(Φ b ) 2 evaluated at the first Hubble radius crossing (here Φ b and φ are the spatially homogeneous and inhomogeneous parts of the scalar field, H is the Hubble parameter, and an overdot represents a derivative with respect to time). In the de Sitter inflation limit, if the inflation-epoch background scalar-field solution is an ''attractor,'' or if there is sufficient inflation before the scale of interest leaves the Hubble radius, the approximate general expression identically reproduces what we have found. It is also less than an order of magnitude away from our expression in a large fraction of the parameter space of the inflation model we study and is within 2 orders of magnitude of our result in almost all of parameter space. We also show that the more accurate general expression (which the above formula is an approximation of) identically reproduces our results in the simple models studied, provided the inflation-epoch background scalar-field solution is an ''attractor'' or if there is sufficient inflation. The approximate general formula is used to restudy energy-density inhomogeneities in the quartic-potential scalar-field de Sitter inflation model; the difference between the standard result in this model and our result in related models is traced to a difference in the form of the part of the potential used to model ''reheating'' and the end of inflation

  5. A vaccinia virus recombinant transcribing an alphavirus replicon and expressing alphavirus structural proteins leads to packaging of alphavirus infectious single cycle particles.

    Directory of Open Access Journals (Sweden)

    Juana M Sánchez-Puig

    Full Text Available Poxviruses and Alphaviruses constitute two promising viral vectors that have been used extensively as expression systems, or as vehicles for vaccine purposes. Poxviruses, like vaccinia virus (VV are well-established vaccine vectors having large insertion capacity, excellent stability, and ease of administration. In turn, replicons derived from Alphaviruses like Semliki Forest virus (SFV are potent protein expression and immunization vectors but stocks are difficult to produce and maintain. In an attempt to demonstrate the use of a Poxvirus as a means for the delivery of small vaccine vectors, we have constructed and characterized VV/SFV hybrid vectors. A SFV replicon cDNA was inserted in the VV genome and placed under the control of a VV early promoter. The replicon, transcribed from the VV genome as an early transcript, was functional, and thus capable of initiating its own replication and transcription. Further, we constructed a VV recombinant additionally expressing the SFV structural proteins under the control of a vaccinia synthetic early/late promoter. Infection with this recombinant produced concurrent transcription of the replicon and expression of SFV structural proteins, and led to the generation of replicon-containing SFV particles that were released to the medium and were able to infect additional cells. This combined VV/SFV system in a single virus allows the use of VV as a SFV delivery vehicle in vivo. The combination of two vectors, and the possibility of generating in vivo single-cycle, replicon containing alphavirus particles, may open new strategies in vaccine development or in the design of oncolytic viruses.

  6. A vaccinia virus recombinant transcribing an alphavirus replicon and expressing alphavirus structural proteins leads to packaging of alphavirus infectious single cycle particles.

    Science.gov (United States)

    Sánchez-Puig, Juana M; Lorenzo, María M; Blasco, Rafael

    2013-01-01

    Poxviruses and Alphaviruses constitute two promising viral vectors that have been used extensively as expression systems, or as vehicles for vaccine purposes. Poxviruses, like vaccinia virus (VV) are well-established vaccine vectors having large insertion capacity, excellent stability, and ease of administration. In turn, replicons derived from Alphaviruses like Semliki Forest virus (SFV) are potent protein expression and immunization vectors but stocks are difficult to produce and maintain. In an attempt to demonstrate the use of a Poxvirus as a means for the delivery of small vaccine vectors, we have constructed and characterized VV/SFV hybrid vectors. A SFV replicon cDNA was inserted in the VV genome and placed under the control of a VV early promoter. The replicon, transcribed from the VV genome as an early transcript, was functional, and thus capable of initiating its own replication and transcription. Further, we constructed a VV recombinant additionally expressing the SFV structural proteins under the control of a vaccinia synthetic early/late promoter. Infection with this recombinant produced concurrent transcription of the replicon and expression of SFV structural proteins, and led to the generation of replicon-containing SFV particles that were released to the medium and were able to infect additional cells. This combined VV/SFV system in a single virus allows the use of VV as a SFV delivery vehicle in vivo. The combination of two vectors, and the possibility of generating in vivo single-cycle, replicon containing alphavirus particles, may open new strategies in vaccine development or in the design of oncolytic viruses.

  7. Thermodynamic and economic analysis of a gas turbine combined cycle plant with oxy-combustion

    Science.gov (United States)

    Kotowicz, Janusz; Job, Marcin

    2013-12-01

    This paper presents a gas turbine combined cycle plant with oxy-combustion and carbon dioxide capture. A gas turbine part of the unit with the operating parameters is presented. The methodology and results of optimization by the means of a genetic algorithm for the steam parts in three variants of the plant are shown. The variants of the plant differ by the heat recovery steam generator (HRSG) construction: the singlepressure HRSG (1P), the double-pressure HRSG with reheating (2PR), and the triple-pressure HRSG with reheating (3PR). For obtained results in all variants an economic evaluation was performed. The break-even prices of electricity were determined and the sensitivity analysis to the most significant economic factors were performed.

  8. A Geometry-Based Cycle Slip Detection and Repair Method with Time-Differenced Carrier Phase (TDCP for a Single Frequency Global Position System (GPS + BeiDou Navigation Satellite System (BDS Receiver

    Directory of Open Access Journals (Sweden)

    Chuang Qian

    2016-12-01

    Full Text Available As the field of high-precision applications based on carriers continues to expand, the development of low-cost, small, modular receivers and their application in diverse scenarios and situations with complex data quality has increased the requirements of carrier-phase data preprocessing. A new geometry-based cycle slip detection and repair method based on Global Position System (GPS + BeiDou Navigation Satellite System (BDS is proposed. The method uses a Time-differenced Carrier Phase (TDCP model, which eliminates the Inner-System Bias (ISB between GPS and BDS, and it is conducive to the effective combination of GPS and BDS. It avoids the interference of the noise of the pseudo-range with cycle slip detection, while the cycle slips are preserved as integers. This method does not limit the receiver frequency number, and it is applicable to single-frequency data. The process is divided into two steps to detect and repair cycle slip. The first step is cycle slip detection, using the Improved Local Analysis Method (ILAM to find satellites that have cycle slips; The second step is to repair the cycle slips, including estimating the float solution of changes in ambiguities at the satellites that have cycle slips with the least squares method and the integer solution of the cycle slips by rounding. In the process of rounding, in addition to the success probability, a decimal test is carried out to validate the result. Finally, experiments with filed test data are carried out to prove the effectiveness of this method. The results show that the detectable cycle slips number with GPS + BDS is much greater than that with GPS. The method can also detect the non-integer outliers while fixing the cycle slip. The maximum decimal bias in repair is less than that with GPS. It implies that this method takes full advantages of multi-system.

  9. A Geometry-Based Cycle Slip Detection and Repair Method with Time-Differenced Carrier Phase (TDCP) for a Single Frequency Global Position System (GPS) + BeiDou Navigation Satellite System (BDS) Receiver.

    Science.gov (United States)

    Qian, Chuang; Liu, Hui; Zhang, Ming; Shu, Bao; Xu, Longwei; Zhang, Rufei

    2016-12-05

    As the field of high-precision applications based on carriers continues to expand, the development of low-cost, small, modular receivers and their application in diverse scenarios and situations with complex data quality has increased the requirements of carrier-phase data preprocessing. A new geometry-based cycle slip detection and repair method based on Global Position System (GPS) + BeiDou Navigation Satellite System (BDS) is proposed. The method uses a Time-differenced Carrier Phase (TDCP) model, which eliminates the Inner-System Bias (ISB) between GPS and BDS, and it is conducive to the effective combination of GPS and BDS. It avoids the interference of the noise of the pseudo-range with cycle slip detection, while the cycle slips are preserved as integers. This method does not limit the receiver frequency number, and it is applicable to single-frequency data. The process is divided into two steps to detect and repair cycle slip. The first step is cycle slip detection, using the Improved Local Analysis Method (ILAM) to find satellites that have cycle slips; The second step is to repair the cycle slips, including estimating the float solution of changes in ambiguities at the satellites that have cycle slips with the least squares method and the integer solution of the cycle slips by rounding. In the process of rounding, in addition to the success probability, a decimal test is carried out to validate the result. Finally, experiments with filed test data are carried out to prove the effectiveness of this method. The results show that the detectable cycle slips number with GPS + BDS is much greater than that with GPS. The method can also detect the non-integer outliers while fixing the cycle slip. The maximum decimal bias in repair is less than that with GPS. It implies that this method takes full advantages of multi-system.

  10. Heat-transfer analysis of double-pipe heat exchangers for indirect-cycle SCW NPP

    Science.gov (United States)

    Thind, Harwinder

    SuperCritical-Water-cooled Reactors (SCWRs) are being developed as one of the Generation-IV nuclear-reactor concepts. SuperCritical Water (SCW) Nuclear Power Plants (NPPs) are expected to have much higher operating parameters compared to current NPPs, i.e., pressure of about 25 MPa and outlet temperature up to 625 °C. This study presents the heat transfer analysis of an intermediate Heat exchanger (HX) design for indirect-cycle concepts of Pressure-Tube (PT) and Pressure-Vessel (PV) SCWRs. Thermodynamic configurations with an intermediate HX gives a possibility to have a single-reheat option for PT and PV SCWRs without introducing steam-reheat channels into a reactor. Similar to the current CANDU and Pressurized Water Reactor (PWR) NPPs, steam generators separate the primary loop from the secondary loop. In this way, the primary loop can be completely enclosed in a reactor containment building. This study analyzes the heat transfer from a SCW primary (reactor) loop to a SCW and Super-Heated Steam (SHS) secondary (turbine) loop using a double-pipe intermediate HX. The numerical model is developed with MATLAB and NIST REFPROP software. Water from the primary loop flows through the inner pipe, and water from the secondary loop flows through the annulus in the counter direction of the double-pipe HX. The analysis on the double-pipe HX shows temperature and profiles of thermophysical properties along the heated length of the HX. It was found that the pseudocritical region has a significant effect on the temperature profiles and heat-transfer area of the HX. An analysis shows the effect of variation in pressure, temperature, mass flow rate, and pipe size on the pseudocritical region and the heat-transfer area of the HX. The results from the numerical model can be used to optimize the heat-transfer area of the HX. The higher pressure difference on the hot side and higher temperature difference between the hot and cold sides reduces the pseudocritical-region length, thus

  11. Steam plant: Steam turbines for combined cycles

    Science.gov (United States)

    Schrieken, J.

    Parameters affecting steam turbines design are discussed and it is concluded that steam turbines for combined cycles are suitable for: powers between 1 and 250 MW; driving a generator, via a gearbox if necessary; drive through of powers which can be up to three times their own power; and ground level installation with up, side, or axial exhaust for condensing turbine applications. Parameters affecting the steam turbine performance are discussed: inlet conditions and flows, sliding inlet conditions, reheat cycles, fired and unfired heat recovery steam generators, cogeneration systems, and combined cycle for process steam supply. Aerodynamic design aspects of steam turbines for combined cycles are discussed. It is concluded that steam turbines for combined cycles have a large range of special requirements. Some typical aspects are: large exhaust annular areas and special exhaust arrangements for condensing steam turbines, drive through of the power of the gas turbines, high influence on the total cycle performance optimization, and a wide variety of extraction systems for cogeneration.

  12. Prevention of multiple pregnancies in couples with unexplained or mild male subfertility : randomised controlled trial of in vitro fertilisation with single embryo transfer or in vitro fertilisation in modified natural cycle compared with intrauterine insemination with controlled ovarian hyperstimulation

    NARCIS (Netherlands)

    Bensdorp, A. J.; Tjon-Kon-Fat, R. I.; Bossuyt, P. M. M.; Koks, C. A. M.; Oosterhuis, G. J. E.; Hoek, A.; Hompes, P. G. A.; Broekmans, F. J. M.; Verhoeve, H. R.; de Bruin, J. P.; van Golde, R.; Repping, S.; Cohlen, B. J.; Lambers, M. D. A.; van Bommel, P. F.; Slappendel, E.; Perquin, D.; Smeenk, J. M.; Pelinck, M. J.; Gianotten, J.; Hoozemans, D. A.; Maas, J. W. M.; Eijkemans, M. J. C.; van der Veen, F.; Mol, B. W. J.; van Wely, M.

    2015-01-01

    Objectives To compare the effectiveness of in vitro fertilisation with single embryo transfer or in vitro fertilisation in a modified natural cycle with that of intrauterine insemination with controlled ovarian hyperstimulation in terms of a healthy child. Design Multicentre, open label, three arm,

  13. In vitro gastrointestinal digestion of pea protein isolate as a function of pH, food matrices, autoclaving, high-pressure and re-heat treatments

    OpenAIRE

    Laguna, Laura; PICOUET, Pierre; Guàrdia, M. Dolors; Renard, Catherine; Sarkar, Anwesha

    2017-01-01

    This study investigated the influence of pH and processing conditions (autoclave at 93 °C/13 min or high pressure processing (HPP) at 600 MPa/5 min without/with follow-up reheating at 80 °C/30 min) on the digestibility of pea protein isolate. Both aqueous solutions and real food matrices (apple and carrot purees) containing pea protein was examined at 37 °C. In vitro gastrointestinal digestion was followed using sodium dodecyl sulphate polyacrylamide gel electrophoresis, titrimetric technique...

  14. Gravitino or axino dark matter with reheat temperature as high as 10{sup 16} GeV

    Energy Technology Data Exchange (ETDEWEB)

    Co, Raymond T. [Berkeley Center for Theoretical Physics, Department of Physics, University of California,366 LeConte Hall MC 7300, Berkeley, CA 94720 (United States); Theoretical Physics Group, Lawrence Berkeley National Laboratory,1 Cyclotron Rd., Berkeley, CA 94720 (United States); D’Eramo, Francesco [Department of Physics, University of California Santa Cruz,1156 High Street, Santa Cruz, CA 95064 (United States); Santa Cruz Institute for Particle Physics,1156 High Street, Santa Cruz, CA 95064 (United States); Hall, Lawrence J. [Berkeley Center for Theoretical Physics, Department of Physics, University of California,366 LeConte Hall MC 7300, Berkeley, CA 94720 (United States); Theoretical Physics Group, Lawrence Berkeley National Laboratory,1 Cyclotron Rd., Berkeley, CA 94720 (United States)

    2017-03-01

    A new scheme for lightest supersymmetric particle (LSP) dark matter is introduced and studied in theories of TeV supersymmetry with a QCD axion, a, and a high reheat temperature after inflation, T{sub R}. A large overproduction of axinos (ã) and gravitinos (G̃) from scattering at T{sub R}, and from freeze-in at the TeV scale, is diluted by the late decay of a saxion condensate that arises from inflation. The two lightest superpartners are ã, with mass of order the TeV scale, and G̃ with mass m{sub 3/2} anywhere between the keV and TeV scales, depending on the mediation scale of supersymmetry breaking. Dark matter contains both warm and cold components: for G̃ LSP the warm component arises from ã→G̃a, while for ã LSP the warm component arises from G̃→ãa. The free-streaming scale for the warm component is predicted to be of order 1 Mpc (and independent of m{sub 3/2} in the case of G̃ LSP). T{sub R} can be as high as 10{sup 16} GeV, for any value of m{sub 3/2}, solving the gravitino problem. The PQ symmetry breaking scale V{sub PQ} depends on T{sub R} and m{sub 3/2} and can be anywhere in the range (10{sup 10}−10{sup 16}) GeV. Detailed predictions are made for the lifetime of the neutralino LOSP decaying to ã+h/Z and G̃+h/Z/γ, which is in the range of (10{sup −1}−10{sup 6})m over much of parameter space. For an axion misalignment angle of order unity, the axion contribution to dark matter is sub-dominant, except when V{sub PQ} approaches 10{sup 16} GeV.

  15. Conceptual Mean-Line Design of Single and Twin-Shaft Oxy-Fuel Gas Turbine in a Semiclosed Oxy-Fuel Combustion Combined Cycle.

    Science.gov (United States)

    Sammak, Majed; Thorbergsson, Egill; Grönstedt, Tomas; Genrup, Magnus

    2013-08-01

    The aim of this study was to compare single- and twin-shaft oxy-fuel gas turbines in a semiclosed oxy-fuel combustion combined cycle (SCOC-CC). This paper discussed the turbomachinery preliminary mean-line design of oxy-fuel compressor and turbine. The conceptual turbine design was performed using the axial through-flow code luax-t, developed at Lund University. A tool for conceptual design of axial compressors developed at Chalmers University was used for the design of the compressor. The modeled SCOC-CC gave a net electrical efficiency of 46% and a net power of 106 MW. The production of 95% pure oxygen and the compression of CO 2 reduced the gross efficiency of the SCOC-CC by 10 and 2 percentage points, respectively. The designed oxy-fuel gas turbine had a power of 86 MW. The rotational speed of the single-shaft gas turbine was set to 5200 rpm. The designed turbine had four stages, while the compressor had 18 stages. The turbine exit Mach number was calculated to be 0.6 and the calculated value of AN 2 was 40 · 10 6 rpm 2 m 2 . The total calculated cooling mass flow was 25% of the compressor mass flow, or 47 kg/s. The relative tip Mach number of the compressor at the first rotor stage was 1.15. The rotational speed of the twin-shaft gas generator was set to 7200 rpm, while that of the power turbine was set to 4800 rpm. A twin-shaft turbine was designed with five turbine stages to maintain the exit Mach number around 0.5. The twin-shaft turbine required a lower exit Mach number to maintain reasonable diffuser performance. The compressor turbine was designed with two stages while the power turbine had three stages. The study showed that a four-stage twin-shaft turbine produced a high exit Mach number. The calculated value of AN 2 was 38 · 10 6 rpm 2 m 2 . The total calculated cooling mass flow was 23% of the compressor mass flow, or 44 kg/s. The compressor was designed with 14 stages. The preliminary design parameters of the turbine and

  16. Prevention of multiple pregnancies in couples with unexplained or mild male subfertility: randomised controlled trial of in vitro fertilisation with single embryo transfer or in vitro fertilisation in modified natural cycle compared with intrauterine insemination with controlled ovarian hyperstimulation.

    Science.gov (United States)

    Bensdorp, A J; Tjon-Kon-Fat, R I; Bossuyt, P M M; Koks, C A M; Oosterhuis, G J E; Hoek, A; Hompes, P G A; Broekmans, F J M; Verhoeve, H R; de Bruin, J P; van Golde, R; Repping, S; Cohlen, B J; Lambers, M D A; van Bommel, P F; Slappendel, E; Perquin, D; Smeenk, J M; Pelinck, M J; Gianotten, J; Hoozemans, D A; Maas, J W M; Eijkemans, M J C; van der Veen, F; Mol, B W J; van Wely, M

    2015-01-09

    To compare the effectiveness of in vitro fertilisation with single embryo transfer or in vitro fertilisation in a modified natural cycle with that of intrauterine insemination with controlled ovarian hyperstimulation in terms of a healthy child. Multicentre, open label, three arm, parallel group, randomised controlled non-inferiority trial. 17 centres in the Netherlands. Couples seeking fertility treatment after at least 12 months of unprotected intercourse, with the female partner aged between 18 and 38 years, an unfavourable prognosis for natural conception, and a diagnosis of unexplained or mild male subfertility. Three cycles of in vitro fertilisation with single embryo transfer (plus subsequent cryocycles), six cycles of in vitro fertilisation in a modified natural cycle, or six cycles of intrauterine insemination with ovarian hyperstimulation within 12 months after randomisation. The primary outcome was birth of a healthy child resulting from a singleton pregnancy conceived within 12 months after randomisation. Secondary outcomes were live birth, clinical pregnancy, ongoing pregnancy, multiple pregnancy, time to pregnancy, complications of pregnancy, and neonatal morbidity and mortality 602 couples were randomly assigned between January 2009 and February 2012; 201 were allocated to in vitro fertilisation with single embryo transfer, 194 to in vitro fertilisation in a modified natural cycle, and 207 to intrauterine insemination with controlled ovarian hyperstimulation. Birth of a healthy child occurred in 104 (52%) couples in the in vitro fertilisation with single embryo transfer group, 83 (43%) in the in vitro fertilisation in a modified natural cycle group, and 97 (47%) in the intrauterine insemination with controlled ovarian hyperstimulation group. This corresponds to a risk, relative to intrauterine insemination with ovarian hyperstimulation, of 1.10 (95% confidence interval 0.91 to 1.34) for in vitro fertilisation with single embryo transfer and 0.91 (0

  17. The seed's protein and oil content, fatty acid composition, and growing cycle length of a single genotype of chia (Salvia hispanica L.) as affected by environmental factors.

    Science.gov (United States)

    Ayerza, Ricardo

    2009-01-01

    As a botanical source, variability in chia seed composition could be expected between growing locations, and between years within a location, due to genotype and environment effects as well genetic x environment's interactions. The objective of the present study was to determine the location effect on the growing cycle length, and seed's protein content, lipid content, and fatty acid profiles, of a single chia genotype. Seeds of chia genotype Tzotzol grown on eight sites in five different ecosystems were tested. One site was in Argentina, in the Semi-Arid Chaco ecosystem (T(5)); one was in Bolivia, in the Sub-Humid Chaco ecosystem (T(4)); and six in Ecuador, one in the Coastal Desert (T(3)), two on the Tropical Rain Forest (T(2)), and three in the Inter-Andean Dry Valley ecosystem (T(1)). Seeds from plants grown in T(4) and in T(3) contained significantly (P seeds from the other three ecosystems. No significant (P Seeds from T(1) and T(5) ecosystems, with 33.5 and 32.2%, respectively, were the numerically highest oil content producers, but their results were only significantly (P seeds. Significant (P oils from seeds grown in different ecosystems were detected, however. Oil of seeds grown in the T(3) ecosystem had the palmitic, stearic and oleic fatty acids' highest contents. Palmitic and oleic fatty acid levels were significantly (P seeds grown in the T(1) ecosystem, and stearic when was compared to that of seeds grown in the T(5) ecosystem; omega-6 linoleic fatty acid content was significantly (P oils of seeds produced in T(1), and T(2) than in those produced in T(3), T(4), and T(5) ecosystems; omega-3 alpha-linolenic fatty acid content was significantly (P seeds produced in T(1), than in those produced in T(3), T(4), and T(5), but not in those produced in T(2).

  18. Thermodynamic feasibility of alternative supercritical CO2 Brayton cycles integrated with an ejector

    International Nuclear Information System (INIS)

    Padilla, Ricardo Vasquez; Too, Yen Chean Soo; Benito, Regano; McNaughton, Robbie; Stein, Wes

    2016-01-01

    Highlights: • Three S-CO 2 Brayton cycle configurations assisted by ejector were proposed. • The Recompression with ejector and intercooling showed the best thermal efficiency. • The proposed cycles can achieve a reduction up to 77% in the heater inlet pressure. - Abstract: Supercritical CO 2 Brayton cycle has emerged as an alternative power block for Concentrated Solar Thermal (CST) systems and nuclear plants. In order to optimise the thermal performance of the Supercritical CO 2 Brayton cycles, a combination of high pressure and temperature are required. The high pressure of the S-CO 2 Brayton cycles has a remarkable effect on not only the thermal performance of the cycle but also the thermodynamic and mechanical performance of the solar receiver. In this paper, three S-CO 2 Brayton cycle configurations without reheat are proposed by introducing an ejector prior the heater, which reduces the pressure at the solar receiver. A comprehensive thermodynamic analysis and a multi-objective optimisation were performed to study the thermodynamic feasibility of the proposed cycles. The effect of the cycle pressure ratios, turbine split ratio, turbine inlet temperature and exit pressure of the ejector on the thermal performance and output parameters of the S-CO 2 Brayton cycles assisted by an ejector was analysed. The proposed configurations were compared with the conventional S-CO 2 Brayton cycles without reheat and referenced steam Rankine cycles (projected thermal efficiencies of 0.416–0.47 in 2020–2025). The results showed that under some operating conditions, the proposed configurations assisted by an ejector can achieve higher efficiencies than the referenced steam Rankine cycles. As the ejector exit pressure increased, the thermal performance of the proposed configurations approached the conventional supercritical CO 2 Brayton cycles.

  19. The extension of Ubungo power plant in Dar es Salaam, Tanzania, to a combined cycle - A prestudy

    Energy Technology Data Exchange (ETDEWEB)

    Grinneland, L.; Oehrstroem, K.

    1996-05-01

    The report deals with the consequences concerning a future extension of Ubungo Power Plant. Today the power plant consists of four gas turbines, two of model General Electric LM6000 and two of model ABB Stal GT10 of which the latter were the ones focused on. In the report four different applications are presented; Simple two pressure system, Two pressure system with reheat, Two pressure system with heat exchange between feedwater and condensate, and single pressure system with an additional evaporating loop. The calculations are divided into three sections; thermodynamic calculations, calculations of the heat exchanger surface areas, and economic calculations. From the thermodynamic calculations the applications with the highest thermal efficiency was selected. The power output increased with about 55% and the thermal efficiency of the complete combined cycle is 48.2%. This is, of course, a theoretical value calculated without consideration to a number of losses that will decrease both the power output and the thermal efficiency. At part load (50% load assumed, i.e. one gas turbine is operating) the thermal efficiency is 46.7%. The economic calculations indicated that the extension is highly worthwhile in an economic point of view; both cases studied have a payback time of less than six years for full load operation, provided that the charging system which is to be imposed by the World Bank has come into force. 18 refs, 33 figs

  20. Optimization of Initial Parameters and Fuel Afterburning Ratio in Heat-Recovery Boiler of Single- and Two-Loop Combined-Cycle Plant

    Directory of Open Access Journals (Sweden)

    B. V. Yakovlev

    2007-01-01

    Full Text Available An analysis of influence of initial parameters and fuel afterburning ratio on efficiency of sin­gle- and two-loop combined-cycle plant has been done in the paper.The paper contains fundamentals of combined-cycle plants initial parameters’ optimization and examples for the sets with gas turbines of various efficiency.

  1. Menstrual Cycle

    Science.gov (United States)

    ... To receive General email updates Enter email Submit Menstrual Cycle The menstrual cycle is the hormonal process ... Preventing problems with your menstrual cycle View more Menstrual Cycle resources Related information Endometriosis Infertility Polycystic ovary ...

  2. Indirect-fired gas turbine dual fuel cell power cycle

    Science.gov (United States)

    Micheli, Paul L.; Williams, Mark C.; Sudhoff, Frederick A.

    1996-01-01

    A fuel cell and gas turbine combined cycle system which includes dual fuel cell cycles combined with a gas turbine cycle wherein a solid oxide fuel cell cycle operated at a pressure of between 6 to 15 atms tops the turbine cycle and is used to produce CO.sub.2 for a molten carbonate fuel cell cycle which bottoms the turbine and is operated at essentially atmospheric pressure. A high pressure combustor is used to combust the excess fuel from the topping fuel cell cycle to further heat the pressurized gas driving the turbine. A low pressure combustor is used to combust the excess fuel from the bottoming fuel cell to reheat the gas stream passing out of the turbine which is used to preheat the pressurized air stream entering the topping fuel cell before passing into the bottoming fuel cell cathode. The CO.sub.2 generated in the solid oxide fuel cell cycle cascades through the system to the molten carbonate fuel cell cycle cathode.

  3. Infertility treatment strategy involving combined freeze-all embryos and single vitrified-warmed embryo transfer during hormonal replacement cycle for in vitro fertilization of women with hypogonadotropic hypogonadism.

    Science.gov (United States)

    Kuroda, Keiji; Ezoe, Kenji; Kato, Keiichi; Yabuuchi, Akiko; Segawa, Tomoya; Kobayashi, Tamotsu; Ochiai, Asako; Katoh, Noriko; Takeda, Satoru

    2018-02-13

    Hypogonadotropic hypogonadism (HH) is a condition caused by the deficient secretion of pituitary gonadotropins, leading to diminished ovarian function. Several studies of in vitro fertilization (IVF) in women with HH revealed acceptable clinical pregnancy outcomes but high multiple pregnancy rates after multiple fresh embryo transfer (ET). The purpose of this study was to analyze the outcomes of combined freeze-all embryos and single vitrified-warmed ET in women with HH. Of 91 infertile women with HH (basal luteinizing hormone and follicle-stimulating hormone levels <2.0 mIU/mL), we excluded patients aged ≥40 years (n = 2) and women who preferred fresh ET (n = 10). Seventy-nine women underwent 117 oocyte retrieval cycles and 135 vitrified-warmed ET during hormone replacement (HR) cycles from 2008 to 2014 at the Kato Ladies Clinic and Juntendo University Hospital. In 26 single cleavage ET cycles, the rates of clinical pregnancy and live birth were 34.6% (9/26 ET) and 26.9% (7/26 ET), respectively. Regarding the outcomes after single vitrified-warmed blastocyst transfer, clinical pregnancy and live birth rates were 65.1% (71/109 ET) and 50.5% (55/109 ET), respectively. Multiple conceptions and ovarian hyperstimulation syndrome did not occur in any of the women with HH. Our results demonstrated that IVF followed by single vitrified-warmed ET in adjusted endocrine milieu during the HR cycle is an effective fertility treatment for women with HH and decreases the incidence of complications, including multiple conceptions. © 2018 Japan Society of Obstetrics and Gynecology.

  4. Comparison of "sandwich chemo-radiotherapy" and six cycles of chemotherapy followed by adjuvant radiotherapy in patients with stage IIIC endometrial cancer: a single center experience.

    Science.gov (United States)

    Dogan, Nasuh Utku; Yavas, Guler; Yavas, Cagdas; Ata, Ozlem; Yılmaz, Setenay Arzu; Celik, Cetin

    2013-10-01

    To compare "sandwich chemo-radiotherapy" with six cycles of chemotherapy followed by adjuvant radiotherapy with respect to tolerability and acute toxicity. Twenty-five women with surgically staged IIIC endometrial cancer were included. Treatment consisted of either three cycles of paclitaxel (175 mg/m²) and carboplatin (AUC 6) on a q21-day schedule followed by irradiation (45-50.4 Gy) or six cycles of the same chemotherapy followed by radiotherapy. Acute toxicity related to either chemotherapy or radiotherapy was evaluated. Median age was 61.5 years (range 36-83 years). Eleven patients had sandwich chemo-radiotherapy, and the other 14 patients had 6 cycles of chemotherapy followed by radiotherapy. Three out of the five patients who could not complete all the cycles in the sandwich chemo-radiotherapy group had pelvic and para-aortic radiotherapy. Acute radiotherapy related grade 1-2 gastrointestinal system (GIS) and genitourinary system (GUS) toxicities were observed in 72.8 and 63.6 % of patients, respectively, for sandwich group. Undesired treatment breaks in the course of radiotherapy were observed in six patients for sandwich chemo-radiotherapy and in one patient receiving six cycles of chemotherapy followed by radiotherapy. All the patients who had undesired treatment breaks in the sandwich chemo-radiotherapy group had pelvic and para-aortic radiotherapy. Sandwich chemo-radiotherapy seems to be more toxic particularly for patients who had pelvic and para-aortic irradiation. Therefore, it might be more convenient to delay radiotherapy after six cycles of chemotherapy for patients with the indication of pelvic para-aortic radiotherapy.

  5. Control of lightness and firmness of cold and reheated frankfurter-type sausages using different spectroscopic methods applied to raw batter.

    Science.gov (United States)

    Egelandsdal, B; Dingstad, G I; Tøgersen, G; Hildrum, K I

    2007-03-01

    Muscle types and collagen, fat, and muscle protein minus collagen were varied in cooked frankfurter-type sausages made from beef and pork meat as well as pork backfat. The content of collagen was fixed at preset levels with pork rind. The amount of total muscle protein in the sausages varied between 5.9% and 11.9% and the fat between 16.1% and 22.1%. The collagen content varied between 1.3% and 4%. Spectroscopic measurements (near-infrared reflectance spectra 1100 to 2500 nm; front-face autofluorescence emission spectra 360 to 640 nm) on raw batters were used to predict the amounts of total muscle protein minus collagen, collagen, myoglobin, and fat (biochemical components), L* values from a Minolta chromameter, and firmness of cold (22 degrees C) and reheated sausages (60 degrees C). Lightness of sausages was most accurately determined from the batter data with a Minolta chromameter or the autofluorescence measurement system. Firmness of cold sausages could be described by the amounts of biochemical components plus the type of muscle used in the sausage. The 2nd-best approach was to use the shape of the near-infrared spectra to determine firmness. This was possible as the shape of near-infrared spectra depended on total protein content, and total protein content largely determined the firmness of cold sausages. If the sausages were reheated to 60 degrees C, near-infrared spectroscopy alone determined firmness of the sausages with a lower accuracy than a combined solution of fluorescence and near-infrared spectroscopy. The 2 spectroscopic techniques could thus be used to estimate the amount of biochemical components in sausages. Once these components were known, firmness could be calculated from a model between the amounts of biochemical components and firmness. For reheated sausages, as opposed to cold ones, there was a need to differentiate between collagen and the other muscle proteins in order to determine firmness. This was optimally achieved by using both

  6. Method for harvesting rare earth barium copper oxide single crystals

    Science.gov (United States)

    Todt, Volker R.; Sengupta, Suvankar; Shi, Donglu

    1996-01-01

    A method of preparing high temperature superconductor single crystals. The method of preparation involves preparing precursor materials of a particular composition, heating the precursor material to achieve a peritectic mixture of peritectic liquid and crystals of the high temperature superconductor, cooling the peritectic mixture to quench directly the mixture on a porous, wettable inert substrate to wick off the peritectic liquid, leaving single crystals of the high temperature superconductor on the porous substrate. Alternatively, the peritectic mixture can be cooled to a solid mass and reheated on a porous, inert substrate to melt the matrix of peritectic fluid while leaving the crystals melted, allowing the wicking away of the peritectic liquid.

  7. Coupling of Modular High-Temperature Gas-Cooled Reactor with Supercritical Rankine Cycle

    Directory of Open Access Journals (Sweden)

    Shutang Zhu

    2008-01-01

    Full Text Available This paper presents investigations on the possible combination of modular high-temperature gas-cooled reactor (MHTGR technology with the supercritical (SC steam turbine technology and the prospective deployments of the MHTGR SC power plant. Energy conversion efficiency of steam turbine cycle can be improved by increasing the main steam pressure and temperature. Investigations on SC water reactor (SCWR reveal that the development of SCWR power plants still needs further research and development. The MHTGR SC plant coupling the existing technologies of current MHTGR module design with operation experiences of SC FPP will achieve high cycle efficiency in addition to its inherent safety. The standard once-reheat SC steam turbine cycle and the once-reheat steam cycle with life-steam have been studied and corresponding parameters were computed. Efficiencies of thermodynamic processes of MHTGR SC plants were analyzed, while comparisons were made between an MHTGR SC plant and a designed advanced passive PWR - AP1000. It was shown that the net plant efficiency of an MHTGR SC plant can reach 45% or above, 30% higher than that of AP1000 (35% net efficiency. Furthermore, an MHTGR SC plant has higher environmental competitiveness without emission of greenhouse gases and other pollutants.

  8. Multi-stage versus single-stage inflation and deflation cycle for alternating low pressure air mattresses to prevent pressure ulcers in hospitalised patients: a randomised-controlled clinical trial.

    Science.gov (United States)

    Demarré, L; Beeckman, D; Vanderwee, K; Defloor, T; Grypdonck, M; Verhaeghe, S

    2012-04-01

    The duration and the amount of pressure and shear must be reduced in order to minimize the risk of pressure ulcer development. Alternating low pressure air mattresses with multi-stage inflation and deflation cycle of the air cells have been developed to relieve pressure by sequentially inflating and deflating the air cells. Evidence about the effectiveness of this type of mattress in clinical practice is lacking. This study aimed to compare the effectiveness of an alternating low pressure air mattress that has a standard single-stage inflation and deflation cycle of the air cells with an alternating low pressure air mattress with multi-stage inflation and deflation cycle of the air cells. A randomised controlled trial was performed in a convenience sample of 25 wards in five hospitals in Belgium. In total, 610 patients were included and randomly assigned to the experimental group (n=298) or the control group (n=312). In the experimental group, patients were allocated to an alternating low pressure air mattress with multi-stage inflation and deflation cycle of the air cells. In the control group, patients were allocated to an alternating low pressure air mattress with a standard single-stage inflation and deflation cycle of the air cells. The outcome was defined as cumulative pressure ulcer incidence (Grade II-IV). An intention-to-treat analysis was performed. There was no significant difference in cumulative pressure ulcer incidence (Grade II-IV) between both groups (Exp.=5.7%, Contr.=5.8%, p=0.97). When patients developed a pressure ulcer, the median time was 5.0 days in the experimental group (IQR=3.0-8.5) and 8.0 days in the control group (IQR=3.0-8.5) (Mann-Whitney U-test=113, p=0.182). The probability to remain pressure ulcer free during the observation period in this trial did not differ significantly between the experimental group and the control group (log-rank χ(2)=0.013, df=1, p=0.911). An alternating low pressure air mattress with multi-stage inflation

  9. Comparison of oxygen uptake during cycle ergometry with and without functional electrical stimulation in patients with COPD: protocol for a randomised, single-blind, placebo-controlled, cross-over trial.

    Science.gov (United States)

    Medrinal, Clément; Prieur, Guillaume; Debeaumont, David; Robledo Quesada, Aurora; Combret, Yann; Quieffin, Jean; Contal, Olivier; Lamia, Bouchra

    2016-01-01

    Chronic obstructive pulmonary disease (COPD) has systemic repercussions that can lead to peripheral muscle dysfunction. Muscle atrophy reduces aerobic capacity, greatly limiting activities of daily living and quality of life. Pulmonary rehabilitation is the gold standard treatment for these patients, however, patients may not be able to reach sufficient training intensities for benefits to occur. Technologies such as functional electrical stimulation (FES) are currently being adapted and tested to enhance exercise training. We hypothesise that FES coupled with cycling (FES-cycling) will improve maximal uptake of oxygen (VO2) and aerobic capacity more than endurance training with placebo stimulation. A randomised, single-blind, placebo-controlled crossover trial will be carried out to evaluate the effects of FES-cycling on VO2 during endurance exercise on a cycle ergometer in patients with COPD. 25 patients with COPD will carry out two 30 min sessions at a constant load; one session with active and one with placebo FES. The primary outcome is oxygen uptake recorded with a metabolic measurement system. Secondary outcomes include ventilation equivalent for oxygen, ventilation equivalent for carbon dioxide, cardiac output, lactate values, perceived dyspnoea and perceived muscle fatigue. Approval has been granted by our Institutional Review Board (Comité de Protection des Personnes Nord-Ouest 3). The results of the trial will be presented at national and international meetings and published in peer-reviewed journals. NCT02594722.

  10. A {sigma}-T diagram analysis regarding the {gamma}' inhibition in {beta} {r_reversible} {beta}' + {gamma}' cycling in CuAlNi single crystals

    Energy Technology Data Exchange (ETDEWEB)

    Gastien, R. [Dto. Ciencia y Tecnica de Materiales, Instituto de Investigaciones Cientificas y Tecnicas de las Fuerzas Armadas (CITEFA), J.B. de La Salle 4397, 1603 Villa Martelli, Buenos Aires (Argentina)]. E-mail: rgastien@citefa.gov.ar; Corbellani, C.E. [Dto. Ciencia y Tecnica de Materiales, Instituto de Investigaciones Cientificas y Tecnicas de las Fuerzas Armadas (CITEFA), J.B. de La Salle 4397, 1603 Villa Martelli, Buenos Aires (Argentina); Sade, M. [Centro Atomico Bariloche, Comision Nacional de Energia Atomica, 8400 S.C. de Bariloche, Rio Negro (Argentina); Lovey, F.C. [Centro Atomico Bariloche, Comision Nacional de Energia Atomica, 8400 S.C. de Bariloche, Rio Negro (Argentina)

    2006-04-15

    An effect of inhibition of the {gamma}' martensitic structure in thermal and pseudoelastic {beta} {r_reversible} {beta}' + {gamma}' cycling in CuAlNi single crystals reported previously [Gastien R, Corbellani CE, Alvarez Villar HN, Sade M, Lovey FC. Mater Sci Eng A 2003;349:191], and an experiment to determine the new thermodynamic parameters to obtain the stress-induced {gamma}' structure was performed [Gastien R, Corbellani CE, Sade M, Lovey FC. Acta Mater 2005;53:1685]. In this paper, a thermodynamic analysis of this effect using {sigma}-T diagrams is proposed, in order to obtain a proper estimation of the energy involved in the inhibition process for pseudoelastic {beta} {r_reversible} {beta}' + {gamma}' cycling.

  11. Live-cell time-lapse imaging and single-cell tracking of in vitro cultured neural stem cells - Tools for analyzing dynamics of cell cycle, migration, and lineage selection.

    Science.gov (United States)

    Piltti, Katja M; Cummings, Brian J; Carta, Krystal; Manughian-Peter, Ayla; Worne, Colleen L; Singh, Kulbir; Ong, Danier; Maksymyuk, Yuriy; Khine, Michelle; Anderson, Aileen J

    2018-01-15

    Neural stem cell (NSC) cultures have been considered technically challenging for time-lapse analysis due to high motility, photosensitivity, and growth at confluent densities. We have tested feasibility of long-term live-cell time-lapse analysis for NSC migration and differentiation studies. Here, we describe a method to study the dynamics of cell cycle, migration, and lineage selection in cultured multipotent mouse or human NSCs using single-cell tracking during a long-term, 7-14 day live-cell time-lapse analysis. We used in-house made PDMS inserts with five microwells on a glass coverslip petri-dish to constrain NSC into the area of acquisition during long-term live-cell imaging. In parallel, we have defined image acquisition settings for single-cell tracking of cell cycle dynamics using Fucci-reporter mouse NSC for 7 days as well as lineage selection and migration using human NSC for 14 days. Overall, we show that adjustments of live-cell analysis settings can extend the time period of single-cell tracking in mouse or human NSC from 24-72 h up to 7-14 days and potentially longer. However, we emphasize that experimental use of repeated fluorescence imaging will require careful consideration of controls during acquisition and analysis. Copyright © 2017. Published by Elsevier Inc.

  12. Research on structural integration of thermodynamic system for double reheat coal-fired unit with CO2 capture

    Science.gov (United States)

    Wang, Lanjing; Shao, Wenjing; Wang, Zhiyue; Fu, Wenfeng; Zhao, Wensheng

    2018-02-01

    Taking the MEA chemical absorption carbon capture system with 85% of the carbon capture rate of a 660MW ultra-super critical unit as an example,this paper puts forward a new type of turbine which dedicated to supply steam to carbon capture system. The comparison of the thermal systems of the power plant under different steam supply schemes by using the EBSILON indicated optimal extraction scheme for Steam Extraction System in Carbon Capture System. The results show that the cycle heat efficiency of the unit introduced carbon capture turbine system is higher than that of the usual scheme without it. With the introduction of the carbon capture turbine, the scheme which extracted steam from high pressure cylinder’ s steam input point shows the highest cycle thermal efficiency. Its indexes are superior to other scheme, and more suitable for existing coal-fired power plant integrated post combustion carbon dioxide capture system.

  13. Single field inflation in supergravity with a U(1) gauge symmetry

    Energy Technology Data Exchange (ETDEWEB)

    Heurtier, L. [Centre de Physique Théorique, École Polytechnique, CNRS, 91128 Palaiseau (France); Khalil, S.; Moursy, A., E-mail: lucien.heurtier@polytechnique.edu, E-mail: skhalil@zewailcity.edu.eg, E-mail: amoursy@zewailcity.edu.eg [Center for Fundamental Physics, Zewail City of Science and Technology, 6 October City, Cairo (Egypt)

    2015-10-01

    A single field inflation based on a supergravity model with a shift symmetry and U(1) extension of the MSSM is analyzed. We show that one of the real components of the two U(1) charged scalar fields plays the role of inflaton with an effective scalar potential similar to the ''new chaotic inflation'' scenario. Both non-anomalous and anomalous (with Fayet-Iliopoulos term) U(1) are studied. We show that the non-anomalous U(1) scenario is consistent with data of the cosmic microwave background and recent astrophysical measurements. A possible kinetic mixing between U(1) and U(1){sub B−L} is considered in order to allow for natural decay channels of the inflaton, leading to a reheating epoch. Upper limits on the reheating temperature thus turn out to favour an intermediate (∼ O(10{sup 13}) GeV) scale B−L symmetry breaking.

  14. Single field inflation in supergravity with a U(1) gauge symmetry

    Energy Technology Data Exchange (ETDEWEB)

    Heurtier, L. [Centre de Physique Théorique, École Polytechnique, CNRS,91128 Palaiseau (France); Khalil, S. [Center for Fundamental Physics, Zewail City of Science and Technology,6 October City, Cairo (Egypt); Department of Mathematics, Faculty of Science, Ain Shams University,Cairo, 11566 (Egypt); Moursy, A. [Center for Fundamental Physics, Zewail City of Science and Technology,6 October City, Cairo (Egypt)

    2015-10-19

    A single field inflation based on a supergravity model with a shift symmetry and U(1) extension of the MSSM is analyzed. We show that one of the real components of the two U(1) charged scalar fields plays the role of inflaton with an effective scalar potential similar to the “new chaotic inflation” scenario. Both non-anomalous and anomalous (with Fayet-Iliopoulos term) U(1) are studied. We show that the non-anomalous U(1) scenario is consistent with data of the cosmic microwave background and recent astrophysical measurements. A possible kinetic mixing between U(1) and U(1){sub B−L} is considered in order to allow for natural decay channels of the inflaton, leading to a reheating epoch. Upper limits on the reheating temperature thus turn out to favour an intermediate (∼O(10{sup 13}) GeV) scale B−L symmetry breaking.

  15. Analysis and comparison of solar-heat driven Stirling, Brayton and Rankine cycles for space power generation

    International Nuclear Information System (INIS)

    Toro, Claudia; Lior, Noam

    2017-01-01

    This paper presents an analysis of solar-heat driven Brayton, Rankine and Stirling cycles operating in space with different working fluids. Generation of power in space for terrestrial use can represent a great future opportunity: the low-temperature of space (∼3 K), allows the attainment of very high efficiency even with low-temperature heat inputs, and the solar energy input is higher in space than on earth. This paper shows a comparative analysis of advanced Brayton, Rankine and Stirling cycles to improve the understanding of the optimal trade-off between high efficiency and the smallest needed heat rejection area. The effect of the main cycles' operational parameters and plant layouts on efficiency and power to radiator area ratio have been analyzed. The thermal efficiency of regenerative-reheated-intercooled Brayton cycle was found to be the best among the investigated configurations. The power to radiator area ratio was found to increase with the introduction of reheating for both the Rankine and Brayton cycles. Stirling cycles efficiencies are lower than those obtained by the Brayton and Rankine cycles but with values of power to radiator area ratio equal to about half of those obtained by Brayton cycles but much higher than those obtained by the Rankine cycles. - Highlights: • The use of terrestrial thermal cycles for power generation in space has been investigated. • Solar-heat driven Stirling, Brayton and Rankine cycles have been simulated and analyzed. • Different layouts and working fluids have been investigated. • Thermal efficiency and power to radiator area ratio have been calculated for each cycle.

  16. A single preovulatory administration of ulipristal acetate affects the decidualization process of the human endometrium during the receptive period of the menstrual cycle.

    Science.gov (United States)

    Lira-Albarrán, Saúl; Durand, Marta; Barrera, David; Vega, Claudia; Becerra, Rocio García; Díaz, Lorenza; García-Quiroz, Janice; Rangel, Claudia; Larrea, Fernando

    2018-04-27

    In order to get further information on the effects of ulipristal acetate (UPA) upon the process of decidualization of endometrium, a functional analysis of the differentially expressed genes in endometrium (DEG) from UPA treated-versus control-cycles of normal ovulatory women was performed. A list of 1183 endometrial DEG, from a previously published study by our group, was submitted to gene ontology, gene enrichment and ingenuity pathway analyses (IPA). This functional analysis showed that decidualization was a biological process overrepresented. Gene set enrichment analysis identified LIF, PRL, IL15 and STAT3 among the most down-regulated genes within the JAK STAT canonical pathway. IPA showed that decidualization of uterus was a bio-function predicted as inhibited by UPA. The results demonstrated that this selective progesterone receptor modulator, when administered during the periovulatory phase of the menstrual cycle, may affect the molecular mechanisms leading to endometrial decidualization in response to progesterone during the period of maximum embryo receptivity. Copyright © 2018. Published by Elsevier B.V.

  17. Long-term persistence of a single Legionella pneumophila strain possessing the mip gene in a municipal shower despite repeated cycles of chlorination.

    Science.gov (United States)

    Cooper, I R; White, J; Mahenthiralingam, E; Hanlon, G W

    2008-10-01

    The ability of Legionella pneumophila to colonise domestic water systems is a primary cause of outbreaks of Legionnaire's disease in humans. World Health Organization guidelines recommend that drinking water is chlorinated to between 0.2 and 1mg/L [Chlorine in drinking-water. Guidelines for drinking-water quality, 2nd edn. Geneva: World Health Organization; 1996], but L. pneumophila is repeatedly isolated from chlorinated water systems, indicating that this treatment is not effective at preventing colonisation. Current UK guidelines recommend a one-off treatment of 20-50mg/L of free chlorine to remove the bacteria. In this study we report on the persistence of L. pneumophila serogroup 1 in a domestic shower system despite repeated cycles of chlorination at 50mg/L for 1h exposure time, over the course of two and a half years. Persisting isolates were subjected to in-vitro phenotypic analyses and polymerase chain reaction analysis for the toxin-encoding mip gene. Random amplified polymorphic DNA typing was also performed to determine whether the isolates recovered on different occasions were the same strain. We found that seven isolates of L. pneumophila recovered over a two-and-a-half year period are the same genetically defined strain, indicating that the bacteria can persist despite repeated cycles of chlorination after each successive isolation.

  18. SU-D-207A-07: The Effects of Inter-Cycle Respiratory Motion Variation On Dose Accumulation in Single Fraction MR-Guided SBRT Treatment of Renal Cell Carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Stemkens, B; Glitzner, M; Kontaxis, C; Prins, F; Crijns, SPM; Kerkmeijer, L; Lagendijk, J; Berg, CAT van den; Tijssen, RHN [Department of Radiotherapy, University Medical Center Utrecht, Utrecht (Netherlands); Denis de Senneville, B [Imaging Division, University Medical Center Utrecht, Utrecht (Netherlands); IMB, UMR 5251 CNRS/University of Bordeaux (France)

    2016-06-15

    Purpose: To assess the dose deposition in simulated single-fraction MR-Linac treatments of renal cell carcinoma, when inter-cycle respiratory motion variation is taken into account using online MRI. Methods: Three motion characterization methods, with increasing complexity, were compared to evaluate the effect of inter-cycle motion variation and drifts on the accumulated dose for an SBRT kidney MR-Linac treatment: 1) STATIC, in which static anatomy was assumed, 2) AVG-RESP, in which 4D-MRI phase-volumes were time-weighted, based on the respiratory phase and 3) PCA, in which 3D volumes were generated using a PCA-model, enabling the detection of inter-cycle variations and drifts. An experimental ITV-based kidney treatment was simulated in a 1.5T magnetic field on three volunteer datasets. For each volunteer a retrospectively sorted 4D-MRI (ten respiratory phases) and fast 2D cine-MR images (temporal resolution = 476ms) were acquired to simulate MR-imaging during radiation. For each method, the high spatio-temporal resolution 3D volumes were non-rigidly registered to obtain deformation vector fields (DVFs). Using the DVFs, pseudo-CTs (generated from the 4D-MRI) were deformed and the dose was accumulated for the entire treatment. The accuracies of all methods were independently determined using an additional, orthogonal 2D-MRI slice. Results: Motion was most accurately estimated using the PCA method, which correctly estimated drifts and inter-cycle variations (RMSE=3.2, 2.2, 1.1mm on average for STATIC, AVG-RESP and PCA, compared to the 2DMRI slice). Dose-volume parameters on the ITV showed moderate changes (D99=35.2, 32.5, 33.8Gy for STATIC, AVG-RESP and PCA). AVG-RESP showed distinct hot/cold spots outside the ITV margin, which were more distributed for the PCA scenario, since inter-cycle variations were not modeled by the AVG-RESP method. Conclusion: Dose differences were observed when inter-cycle variations were taken into account. The increased inter-cycle

  19. The kinetics of blood lactate in boys during and following a single and repeated all-out sprints of cycling are different than in men.

    Science.gov (United States)

    Engel, Florian Azad; Sperlich, Billy; Stockinger, Christian; Härtel, Sascha; Bös, Klaus; Holmberg, Hans-Christer

    2015-06-01

    This study characterized the impact of high-intensity interval training on the kinetics of blood lactate and performance in trained boys and men. Twenty-one boys (11.4 ± 0.8 years) and 19 men (29.4 ± 5.0 years) performed a set of four 30-s sprints with 2-min of rest and a single 30-s sprint on 2 separate occasions (randomized order) with assessment of performance. Blood lactate was assayed after each sprint and during 30 min of recovery from both tests. The individual time-curves of blood lactate concentration were fitted to the biexponential function as follows: [Formula: see text], where the velocity parameters γ1 and γ2 reflect the capacity to release lactate from the previously active muscle into the blood and to subsequently eliminate lactate from the organism, respectively. In both tests, peak blood lactate concentration was significantly lower in the boys (four 30-s sprints: 12.2 ± 3.6 mmol·L(-1); single 30-s sprint: 8.7 ± 1.8 mmol·L(-1)) than men (four 30-s sprints: 16.1 ± 3.3 mmol·L(-1); single 30-s sprint: 11.5 ± 2.1; p boys exhibited faster γ1 (1.4531 ± 0.65 min; p boys (9.2% ± 13.9%) than men (19.2% ± 11.5%; p = 0.01). In the present study boys, when compared with men, exhibited lower Peak blood lactate concentration; less pronounced decline in performance during the sprints concomitantly with more rapid release and elimination during the single 30-s sprint; and faster elimination of lactate following the four 30-s sprints.

  20. Ultrathin single-crystalline TiO2 nanosheets anchored on graphene to be hybrid network for high-rate and long cycle-life sodium battery electrode application

    Science.gov (United States)

    Shoaib, Anwer; Huang, Yongxin; Liu, Jia; Liu, Jiajia; Xu, Meng; Wang, Ziheng; Chen, Renjie; Zhang, Jiatao; Wu, Feng

    2017-02-01

    In view of the growing concern about energy management issues, sodium ion batteries (SIBs) as cheap and environmentally friendly devices have increasingly received wide research attentions. The high current rate and long cycle-life of SIBs are considered as two key parameters determining its potential for practical applications. In this work, the rigid single-crystalline anatase TiO2 nanosheets (NSs) with a thickness of ∼4 nm has been firstly prepared, based on which a stable nanostructured network consisting of ultrathin anatase TiO2 NSs homogeneously anchored on graphene through chemical bonding (TiO2 NSs-G) has fabricated by hydrothermal process and subsequent calcination treatment. The morphology, crystallization, chemical compositions and the intimate maximum contact between TiO2 NSs and graphene are confirmed by TEM, SEM, XRD, XPS and Raman characterizations. The results of electrochemical performance tests indicated that the TiO2 NSs-G hybrid network could be consider as a promising anode material for SIBs, in assessment of its remarkably high current rate and long cycle-life aside from the improved specific capacity, rate capability and cycle stability.

  1. Rolling cycle amplification based single-color quantum dots–ruthenium complex assembling dyads for homogeneous and highly selective detection of DNA

    Energy Technology Data Exchange (ETDEWEB)

    Su, Chen; Liu, Yufei; Ye, Tai; Xiang, Xia; Ji, Xinghu; He, Zhike, E-mail: zhkhe@whu.edu.cn

    2015-01-01

    Graphical abstract: A universal, label-free, homogeneous, highly sensitive, and selective fluorescent biosensor for DNA detection is developed by using rolling-circle amplification (RCA) based single-color quantum dots–ruthenium complex (QDs–Ru) assembling dyads. - Highlights: • The single-color QDs–Ru assembling dyads were applied in homogeneous DNA assay. • This biosensor exhibited high selectivity against base mismatched sequences. • This biosensor could be severed as universal platform for the detection of ssDNA. • This sensor could be used to detect the target in human serum samples. • This DNA sensor had a good selectivity under the interference of other dsDNA. - Abstract: In this work, a new, label-free, homogeneous, highly sensitive, and selective fluorescent biosensor for DNA detection is developed by using rolling-circle amplification (RCA) based single-color quantum dots–ruthenium complex (QDs–Ru) assembling dyads. This strategy includes three steps: (1) the target DNA initiates RCA reaction and generates linear RCA products; (2) the complementary DNA hybridizes with the RCA products to form long double-strand DNA (dsDNA); (3) [Ru(phen){sub 2}(dppx)]{sup 2+} (dppx = 7,8-dimethyldipyrido [3,2-a:2′,3′-c] phenanthroline) intercalates into the long dsDNA with strong fluorescence emission. Due to its strong binding propensity with the long dsDNA, [Ru(phen){sub 2}(dppx)]{sup 2+} is removed from the surface of the QDs, resulting in restoring the fluorescence of the QDs, which has been quenched by [Ru(phen){sub 2}(dppx)]{sup 2+} through a photoinduced electron transfer process and is overlaid with the fluorescence of dsDNA bonded Ru(II) polypyridyl complex (Ru-dsDNA). Thus, high fluorescence intensity is observed, and is related to the concentration of target. This sensor exhibits not only high sensitivity for hepatitis B virus (HBV) ssDNA with a low detection limit (0.5 pM), but also excellent selectivity in the complex matrix. Moreover

  2. The Effect of Chemical Composition on Microstructure and Properties of Intercritically Reheated Coarse-Grained Heat-Affected Zone in X70 Steels

    Science.gov (United States)

    Zhu, Zhixiong; Kuzmikova, Lenka; Li, Huijun; Barbaro, Frank

    2013-12-01

    The current study investigates the effect of different levels of Ti, N, and Ti/N ratios on microstructure and properties in the intercritically reheated coarse-grained heat-affected zone (ICCGHAZ) of two-pass submerged arc welds in API 5L grade X70 pipe. Gleeble simulation was employed to reproduce the ICCGHAZ of actual welds. Hardness and Charpy V-notch (CVN) tests were performed on the simulated samples. The microstructure of simulated ICCGHAZ was characterized by optical microscopy and scanning electron microscopy (SEM). LePera color etching technique was employed to identify and quantify the martensitic-austenitic (M-A) constituent. Results show that the simulated ICCGHAZ exhibited extremely low toughness, but in the studied range of Ti and N, there was no correlation with Ti/N ratio. The beneficial effect of near-stoichiometric Ti/N ratio observed in coarse-grained heat-affected zone (CGHAZ) did not translate to ICCGHAZ. This was because of the negative effect of the blocky M-A constituent formed on prior austenite grain boundaries.

  3. Computational Study on M1/POM Single-Atom Catalysts (M = Cu, Zn, Ag, and Au; POM = [PW12O40]3-): Metal-Support Interactions and Catalytic Cycle for Alkene Epoxidation.

    Science.gov (United States)

    Liu, Chun-Guang; Jiang, Meng-Xu; Su, Zhong-Min

    2017-09-05

    Geometrical structures, metal-support interactions, and infrared (IR) spectroscopy of a series of M 1 /POM (M = Cu, Zn, Ag, and Au; POM = [PW 12 O 40 ] 3- ) single-atom catalysts (SACs), and catalytic cycle for alkene epoxidation catalyzed by M 1 /POM SACs were studied using density functional theory (DFT) calculations. The calculations demonstrate that the most probable anchoring sties for the isolated single atoms studied here in the M 1 /POM SACs are the fourfold hollow sites on the surface of POM support. The bonding interaction between single metal atom and surface of POM support comes from the molecular orbitals with a mixture of d atomic orbital of metal and 2p group orbital of surface oxygen atoms of POM cage. The calculated adsorption energy of isolated metal atoms in these M 1 /POM SACs indicates that the early transition metals (Cu and Zn) have high thermal stability. The DFT-derived IR spectra show that the four characteristic peaks of free Keggin-type POM structure split into six because of introduction of isolated metal atom. Compared with other metal atoms, the Zn 1 /POM SAC has the high reactivity for activity of dioxygen molecule, because the dioxygen moiety in Zn 1 /POM SAC displays O 2 - · radical feature with [POM 4- ·Zn 2+ O 2 - ·] 3- configuration. Finally, a catalytic cycle for ethylene epoxidation by O 2 catalyzed by Zn 1 /POM SAC was proposed based on our DFT calculations. Supported noble-metal SACs are among the most important catalysts currently. However, noble metals are expensive and of limited supply. Development of non-noble-metal SACs is of essential importance. Therefore, the reported Zn 1 /POM SAC would be very useful to guide the search for SACs into non-noble metals.

  4. Superfluid thermodynamic cycle refrigerator

    Science.gov (United States)

    Swift, Gregory W.; Kotsubo, Vincent Y.

    1992-01-01

    A cryogenic refrigerator cools a heat source by cyclically concentrating and diluting the amount of .sup.3 He in a single phase .sup.3 He-.sup.4 He solution. The .sup.3 He in superfluid .sup.4 He acts in a manner of an ideal gas in a vacuum. Thus, refrigeration is obtained using any conventional thermal cycle, but preferably a Stirling or Carnot cycle. A single phase solution of liquid .sup.3 He at an initial concentration in superfluid .sup.4 He is contained in a first variable volume connected to a second variable volume through a superleak device that enables free passage of .sup.4 He while restricting passage of .sup.3 He. The .sup.3 He is compressed (concentrated) and expanded (diluted) in a phased manner to carry out the selected thermal cycle to remove heat from the heat load for cooling below 1 K.

  5. Effect of Administration of Single Dose GnRH Agonist in Luteal Phase on Outcome of ICSI-ET Cycles in Women with Previous History of IVF/ICSI Failure: A Randomized Controlled Trial

    Science.gov (United States)

    Zafardoust, Simin; Jeddi-Tehrani, Mahmood; Akhondi, Mohammad Mehdi; Sadeghi, Mohammad Reza; Kamali, Koroush; Mokhtar, Sara; Badehnoosh, Bita; Arjmand-Teymouri, Fatemeh; Fatemi, Farnaz; Mohammadzadeh, Afsaneh

    2015-01-01

    Background GnRH agonist administration in the luteal phase has been suggested to beneficially affect the outcome of intracytoplasmic sperm injection (ICSI) and embryo transfer (ET) cycles. This blind randomized controlled study evaluates the effect of GnRH (Gonadotropine Releasing Hormone) agonist administration on ICSI outcome in GnRH antagonist ovarian stimulation protocol in women with 2 or more previous IVF/ICSI-ET failures. Methods One hundred IVF failure women who underwent ICSI cycles and stimulated with GnRH antagonist ovarian stimulation protocol, were included in the study. Women were randomly assigned to intervention (received a single dose injection of GnRH agonist (0.1 mg of Decapeptil) subcutaneously 6 days after oocyte retrieval) and control (did not receive GnRH agonist) groups. Implantation and clinical pregnancy rates were the primary outcome measures. Results Although the age of women, the number of embryos transferred in the current cycle and the quality of the transferred embryos were similar in the two groups, there was a significantly higher rate of implantation (Mann Whitney test, p = 0.041) and pregnancy (32.6% vs. 12.5%, p = 0.030, OR = 3.3, 95%CI, 1.08 to 10.4) in the intervention group. Conclusion Our results suggested that, in addition to routine luteal phase support using progesterone, administration of 0.1 mg of Decapeptil 6 days after oocyte retrieval in women with previous history of 2 or more IVF/ICSI failures led to a significant improvement in implantation and pregnancy rates after ICSI following ovarian stimulation with GnRH antagonist protocol. PMID:25927026

  6. Making theory: I. Producing physics and physicists in postwar America. II. Post-inflation reheating in an expanding universe

    Science.gov (United States)

    Kaiser, David Isaac

    2000-11-01

    This dissertation examines the reinvention of theoretical physics in the United States through pedagogical means after World War II. Physics graduate student enrollments ballooned immediately after the war. The unprecedented enrollments forced questions of procedures and standards for graduate training as never before. At the same time, the crush of numbers spurred an increased bureaucratization and, at least some American physicists feared, a different system of values than what had prevailed during the quieter interwar period. Out of these new bureaucratic and pedagogical developments, theoretical physics became a recognized specialty within American physics, surrounded by new ideas about what theory was for and how students should be trained to do it. Two case studies focus on developments within theoretical physics after the war, using pedagogy as a lens through which to understand the links between practices and practitioners. Within nuclear and particle physics, as Part II discusses, young graduate students and postdoctoral fellows puzzled over how to calculate with, and how to interpret, the simple line-drawings introduced by Richard Feynman in 1948. The number of distinct pictorial forms, calculational roles, and attributed meanings for the simple stick-figures quickly multiplied: rather than commanding a single use or interpretation, the diagrams came to be used for a wide variety of distinct tasks. Some theorists clung to the diagrams even as they declared the original theoretical framework from which the diagrams had sprung to be ``sterile'' and ``dead.'' These young theorists drew the diagrams much the same way as Feynman had, yet read content into them which had no correlate in the older approaches. Part III uses pedagogy to make sense of a similar series of changes within the long-dormant field of gravitational physics. Einstein's gravitational field equations proved to be no more obvious or auto-interpreting than Feynman's diagrams had been

  7. Simultaneous monitoring of the two coupled motors of a single FoF1-ATP synthase by three-color FRET using duty cycle-optimized triple-ALEX

    Science.gov (United States)

    Zarrabi, N.; Ernst, S.; Düser, M. G.; Golovina-Leiker, A.; Becker, W.; Erdmann, R.; Dunn, S. D.; Börsch, M.

    2009-02-01

    FoF1-ATP synthase is the enzyme that provides the 'chemical energy currency' adenosine triphosphate, ATP, for living cells. The formation of ATP is accomplished by a stepwise internal rotation of subunits within the enzyme. Briefly, proton translocation through the membrane-bound Fo part of ATP synthase drives a 10-step rotary motion of the ring of c subunits with respect to the non-rotating subunits a and b. This rotation is transmitted to the γ and ɛ subunits of the F1 sector resulting in 120° steps. In order to unravel this symmetry mismatch we monitor subunit rotation by a single-molecule fluorescence resonance energy transfer (FRET) approach using three fluorophores specifically attached to the enzyme: one attached to the F1 motor, another one to the Fo motor, and the third one to a non-rotating subunit. To reduce photophysical artifacts due to spectral fluctuations of the single fluorophores, a duty cycle-optimized alternating three-laser scheme (DCO-ALEX) has been developed. Simultaneous observation of the stepsizes for both motors allows the detection of reversible elastic deformations between the rotor parts of Fo and F1.

  8. Liquid metal mist cooling and MHD Ericsson cycle for fusion energy conversion

    International Nuclear Information System (INIS)

    Greenspan, E.

    1989-01-01

    The combination of liquid metal mist coolant and a liquid metal MHD (LMMHD) energy conversion system (ECS) based on the Ericsson cycle is being proposed for high temperature fusion reactors. It is shown that the two technologies are highly matchable, both thermodynamically and physically. Thermodynamically, the author enables delivering the fusion energy to the cycle with probably the highest practical average temperature commensurate with a given maximum reactor design constraint. Physically, the mist cooling and LMMHD ECSs can be coupled directly, thus eliminating the need for primary heat exchangers and reheaters. The net result is expected to be a high efficiency, simple and reliable heat transport and ECS. It is concluded that the proposed match could increase the economic viability of fusion reactors, so that a thorough study of the two complementary technologies is recommended. 11 refs., 3 figs

  9. Energetic and Exergetic Analysis of Combined Cycle Power Plant: Part-1 Operation and Performance

    Directory of Open Access Journals (Sweden)

    Abdulrahman Almutairi

    2015-12-01

    Full Text Available Energetic and exergetic analyses are conducted using operating data for Sabiya, a combined cycle power plant (CCPP with an advanced triple pressure reheat heat recovery steam generator (HRSG. Furthermore, a sensitivity analysis is carried out on the HRSG using a recent approach to differentiate between the sources of irreversibility. The proposed system was modelled using the IPSEpro software and further validated by the manufacturer’s data. The performance of the Sabiya CCPP was examined for different climatic conditions, pressure ratios, pinch point temperatures, high-pressure steam, and condenser pressure values. The results confirmed that 60.9% of the total exergy destruction occurs in the combustion chamber, which constitutes the main source of irreversibilities within a system. The exergy destruction was significantly affected by both the pressure ratio and the high-pressure steam, where the relation between them was seen to be inversely proportional. The high-pressure stage contributes about 50% of the exergy destruction within the HRSG compared to other stages and the reheat system, due to the high temperature difference between the streams and the large number of components, which leads to high energy loss to the surroundings. Numerous possibilities for improving the CCPP’s performance are introduced, based on the obtained results.

  10. Energetic and exergetic analysis of Rankine cycles for solar power plants with parabolic trough and thermal storage

    Directory of Open Access Journals (Sweden)

    Cenuşă Victor-Eduard

    2016-01-01

    Full Text Available The paper analyzes the “secondary” circuit (for thermodynamic conversion of a Concentrated Solar Power (CSP plant with thermodynamic cycle, whose mirrors field supplies a thermal power, averaged over a sunny day, of about 100 MW heat. We study the case of parabolic trough solar collector using silicone oil in the “primary” circuit, which limits the peak temperature below 400 °C. The “primary” circuit uses thermal storage, allowing a delay between the power generation in rapport with the solar energy capture. We choose a water-steam cycle, type Hirn. For increasing its efficiency, it has regenerative feed water preheating and steam reheating. We compared, energetic and exergetic, two types of cycles, using a numerical model with iterative structure, developed by the authors. The results showed that the simplified design achieves practically the same thermodynamic performances with the advanced one.

  11. Happy Cycling

    DEFF Research Database (Denmark)

    Geert Jensen, Birgitte; Nielsen, Tom

    2013-01-01

    og Interaktions Design, Aarhus Universitet under opgave teamet: ”Happy Cycling City – Aarhus”. Udfordringen i studieopgaven var at vise nye attraktive løsningsmuligheder i forhold til cyklens og cyklismens integration i byrum samt at påpege relationen mellem design og overordnede diskussioner af...

  12. Glacial cycles

    DEFF Research Database (Denmark)

    Kaufmann, R. K.; Juselius, Katarina

    We use a statistical model, the cointegrated vector autoregressive model, to assess the degree to which variations in Earth's orbit and endogenous climate dynamics can be used to simulate glacial cycles during the late Quaternary (390 kyr-present). To do so, we estimate models of varying complexi...

  13. CYCLE CONTROL

    African Journals Online (AJOL)

    changed to gestodene. Although large- scale comparative trials are needed to confirm this finding, evidence suggests that cycle control with gestodene is better than for monophasic preparations containing desogestrel, norgestimate or levonorgestrel,10 as well as for levonorg- estrel-or norethisterone-containing triphasics.

  14. Coordination cycles

    Czech Academy of Sciences Publication Activity Database

    Steiner, Jakub

    2008-01-01

    Roč. 63, č. 1 (2008), s. 308-327 ISSN 0899-8256 Institutional research plan: CEZ:AV0Z70850503 Keywords : global games * coordination * crises * cycles and fluctuations Subject RIV: AH - Economics Impact factor: 1.333, year: 2008

  15. Coordination cycles

    Czech Academy of Sciences Publication Activity Database

    Steiner, Jakub

    -, č. 274 (2005), s. 1-26 ISSN 1211-3298 Institutional research plan: CEZ:AV0Z70850503 Keywords : coordination * crises * cycles and fluctuations Subject RIV: AH - Economics http://www.cerge-ei.cz/pdf/wp/Wp274.pdf

  16. Understanding Single Adulthood.

    Science.gov (United States)

    Stein, Peter J.

    The life styles and life chances of the unmarried include elements of choices. Singles may be grouped and characterized according to whether their status may be considered stable or temporary. A life cycle, or continuum model of singlehood is reviewed, including its different factors, or phases. A new model for singles is proposed--a life spiral…

  17. Thermodynamic assessment of a wind turbine based combined cycle

    International Nuclear Information System (INIS)

    Rabbani, M.; Dincer, I.; Naterer, G.F.

    2012-01-01

    Combined cycles use the exhaust gases released from a Gas Turbine (GT). Approximately 30–40% of the turbine shaft work is typically used to drive the Compressor. The present study analyzes a system that couples a Wind Turbine (WT) with a combined cycle. It demonstrates how a WT can be used to supply power to the Compressor in the GT cycle and pump fluid through a reheat Rankine cycle, in order to increase the overall power output. Three different configurations are discussed, namely high penetration, low penetration and wind power addition. In the case of a low electricity demand and high penetration configuration, extra wind power is used to compress air which can then be used in the low penetration configuration. During a high load demand, all the wind power is used to drive the pump and compressor and if required additional compressed air is supplied by a storage unit. The analysis shows that increasing the combustion temperature reduces the critical velocity and mass flow rate. Increases in wind speed reduce both energy and exergy efficiency of the overall system. -- Highlights: ► This study analyzes a system that couples a wind turbine with a combined power generation cycle. ► Surplus wind power is used to compress air, which is then stored and used at a later time. ► Increasing the pressure ratio will reduce the work ratio between the Rankine and Brayton cycles. ► A higher combustion temperature will increase the net work output, as well as the system energy and exergy efficiencies.

  18. Fuel cycle

    International Nuclear Information System (INIS)

    Bahm, W.

    1989-01-01

    The situation of the nuclear fuel cycle for LWR type reactors in France and in the Federal Republic of Germany was presented in 14 lectures with the aim to compare the state-of-the-art in both countries. In addition to the momentarily changing fuilds of fuel element development and fueling strategies, the situation of reprocessing, made interesting by some recent developmnts, was portrayed and differences in ultimate waste disposal elucidated. (orig.) [de

  19. Performance of a Supercritical CO2 Bottoming Cycle for Aero Applications

    Directory of Open Access Journals (Sweden)

    Florian Jacob

    2017-03-01

    Full Text Available By 2050, the evolutionary approach to aero engine research may no longer provide meaningful returns on investment, whereas more radical approaches to improving thermal efficiency and reducing emissions might still prove cost effective. One such radical concept is the addition of a secondary power cycle that utilizes the otherwise largely wasted residual heat in the core engine’s exhaust gases. This could provide additional shaft power. Supercritical carbon dioxide closed-circuit power cycles are currently being investigated primarily for stationary power applications, but their high power density and efficiency, even for modest peak cycle temperatures, makes them credible bottoming cycle options for aero engine applications. Through individual geometric design and performance studies for each of the bottoming cycle’s major components, it was determined that a simple combined cycle aero engine could offer a 1.9% mission fuel burn benefit over a state-of-the-art geared turbofan for the year 2050. However, the even greater potential of more complex systems demands further investigation. For example, adding inter-turbine reheat (ITR to the combined cycle is predicted to significantly improve the fuel burn benefit.

  20. Happy Cycling

    DEFF Research Database (Denmark)

    Geert Jensen, Birgitte; Nielsen, Tom

    2013-01-01

    Artiklens formål er at diskutere oplevede kvaliteter og adfærdsaspekter af mobilitet med udgangspunkt i spørgsmålet om cykling i byer og relationen mellem design og adfærd. Artiklen tager afsæt i et studie forløb der involverede studerende fra Urban Design, Industriel Design Arkitektskolen Aarhus...... og Interaktions Design, Aarhus Universitet under opgave teamet: ”Happy Cycling City – Aarhus”. Udfordringen i studieopgaven var at vise nye attraktive løsningsmuligheder i forhold til cyklens og cyklismens integration i byrum samt at påpege relationen mellem design og overordnede diskussioner af...

  1. Safe cycling!

    CERN Document Server

    Anaïs Schaeffer

    2012-01-01

    The HSE Unit will be running a cycling safety campaign at the entrances to CERN's restaurants on 14, 15 and 16 May. Pop along to see if they can persuade you to get back in the saddle!   With summer on its way, you might feel like getting your bike out of winter storage. Well, the HSE Unit has come up with some original ideas to remind you of some of the most basic safety rules. This year, the prevention campaign will be focussing on three themes: "Cyclists and their equipment", "The bicycle on the road", and "Other road users". This is an opportunity to think about the condition of your bike as well as how you ride it. From 14 to 16 May, representatives of the Swiss Office of Accident Prevention and the Touring Club Suisse will join members of the HSE Unit at the entrances to CERN's restaurants to give you advice on safe cycling (see box). They will also be organising three activity stands where you can test your knowle...

  2. Integrated solar combined cycles using gas turbines with partial recuperation and solar integration at different pressure levels

    Science.gov (United States)

    Rovira, Antonio; Sánchez, Consuelo; Fernández, Santiago; Muñoz, Marta; Barbero, Rubén

    2017-06-01

    This work studies and compares two alternatives to improve the solar-to-electricity energy conversion efficiency in integrated solar combined cycle power plants (ISCC), which are based on the use of combined cycles including partial recuperative gas turbines. Each alternative has been integrated into dual and triple pressure levels with reheat heat recovery steam generators (HRSG). Partial recuperation conveys lower heat recovery at the steam generator than in conventional plants, because each MW exchanged in the recuperator is not available at the HRSG. This thermal power decrease at the HRSG may be overcome by the integration of solar energy that is implemented using parabolic trough collectors. Moreover, with such an implementation each solar thermal MW integrated allows a MW of heat recuperation and, thus a MW of fossil fuel saving, thus the solar heat-to-electricity energy conversion rate may reach values up to 50 %, which makes the proposal interesting.

  3. A combined gas cooled nuclear reactor and fuel cell cycle

    Science.gov (United States)

    Palmer, David J.

    Rising oil costs, global warming, national security concerns, economic concerns and escalating energy demands are forcing the engineering communities to explore methods to address these concerns. It is the intention of this thesis to offer a proposal for a novel design of a combined cycle, an advanced nuclear helium reactor/solid oxide fuel cell (SOFC) plant that will help to mitigate some of the above concerns. Moreover, the adoption of this proposal may help to reinvigorate the Nuclear Power industry while providing a practical method to foster the development of a hydrogen economy. Specifically, this thesis concentrates on the importance of the U.S. Nuclear Navy adopting this novel design for its nuclear electric vessels of the future with discussion on efficiency and thermodynamic performance characteristics related to the combined cycle. Thus, the goals and objectives are to develop an innovative combined cycle that provides a solution to the stated concerns and show that it provides superior performance. In order to show performance, it is necessary to develop a rigorous thermodynamic model and computer program to analyze the SOFC in relation with the overall cycle. A large increase in efficiency over the conventional pressurized water reactor cycle is realized. Both sides of the cycle achieve higher efficiencies at partial loads which is extremely important as most naval vessels operate at partial loads as well as the fact that traditional gas turbines operating alone have poor performance at reduced speeds. Furthermore, each side of the cycle provides important benefits to the other side. The high temperature exhaust from the overall exothermic reaction of the fuel cell provides heat for the reheater allowing for an overall increase in power on the nuclear side of the cycle. Likewise, the high temperature helium exiting the nuclear reactor provides a controllable method to stabilize the fuel cell at an optimal temperature band even during transients helping

  4. Reheat cracking of austenitic stainless steels - pre-strain effect on intergranular damage; Fissuration en relaxation des aciers inoxydables austenitiques - influence de l'ecrouissage sur l'endommagement intergranulaire

    Energy Technology Data Exchange (ETDEWEB)

    Auzoux, Q

    2004-01-01

    Welding process induces strain in 316 stainless steel affected zones. Their microstructure was reproduce by rolling of three different steels (316L, 316L(N) et 316H). Traction, creep and relaxation tests were performed at 550 deg C and 600 deg C on smooth, notched and pre-cracked specimens. Pre-strain by rolling increases the hardness and the creep resistance because of the high dislocation density but decreases ductility because of the fast development of intergranular damage. This embrittlement leads to crack propagation during relaxation tests on pre-strained steels without distinction in respect to their carbon or nitrogen content. A new intergranular damage model was built using local micro-cracks measurements and finite elements analysis. Pre-strain effect and stress triaxiality ratio effect are reproduced by the modelling so that the reheat cracking risk near welds can now be estimated. (author)

  5. Your Menstrual Cycle

    Science.gov (United States)

    ... during your menstrual cycle What happens during your menstrual cycle The menstrual cycle includes not just your period, but the ... tool is based on a sample 28-day menstrual cycle, but every woman is different in how ...

  6. Combined cycle plants: Yesterday, today, and tomorrow (review)

    Science.gov (United States)

    Ol'khovskii, G. G.

    2016-07-01

    Gas turbine plants (GTP) for a long time have been developed by means of increasing the initial gas temperature and improvement of the turbo-machines aerodynamics and the efficiency of the critical components air cooling within the framework of a simple thermodynamic cycle. The application of watercooling systems that were used in experimental turbines and studied approximately 50 years ago revealed the fundamental difficulties that prevented the practical implementation of such systems in the industrial GTPs. The steam cooling researches have developed more substantially. The 300 MW power GTPs with a closedloop steam cooling, connected in parallel with the intermediate steam heating line in the steam cycle of the combined cycle plant (CCP) have been built, tested, and put into operation. The designs and cycle arrangements of such GTPs and entire combined cycle steam plants have become substantially more complicated without significant economic benefits. As a result, the steam cooling of gas turbines has not become widespread. The cycles—complicated by the intermediate air cooling under compression and reheat of the combustion products under expansion and their heat recovery to raise the combustion chamber entry temperature of the air—were used, in particular, in the domestic power GTPs with a moderate (700-800°C) initial gas turbine entry temperature. At the temperatures being reached to date (1300-1450°C), only one company, Alstom, applies in their 240-300 MW GTPs the recycled fuel cycle under expansion of gases in the turbine. Although these GTPs are reliable, there are no significant advantages in terms of their economy. To make a forecast of the further improvement of power GTPs, a brief review and assessment of the water cooling and steam cooling of hot components and complication of the GTP cycle by the recycling of fuel under expansion of gases in the turbine has been made. It is quite likely in the long term to reach the efficiency for the

  7. Modeling and experimental results for condensing supercritical CO2 power cycles.

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Steven Alan; Conboy, Thomas M.; Radel, Ross F.; Rochau, Gary Eugene

    2011-01-01

    This Sandia supported research project evaluated the potential improvement that 'condensing' supercritical carbon dioxide (S-CO{sub 2}) power cycles can have on the efficiency of Light Water Reactors (LWR). The analytical portion of research project identified that a S-CO{sub 2} 'condensing' re-compression power cycle with multiple stages of reheat can increase LWR power conversion efficiency from 33-34% to 37-39%. The experimental portion of the project used Sandia's S-CO{sub 2} research loop to show that the as designed radial compressor could 'pump' liquid CO{sub 2} and that the gas-cooler's could 'condense' CO{sub 2} even though both of these S-CO{sub 2} components were designed to operate on vapor phase S-CO{sub 2} near the critical point. There is potentially very high value to this research as it opens the possibility of increasing LWR power cycle efficiency, above the 33-34% range, while lowering the capital cost of the power plant because of the small size of the S-CO{sub 2} power system. In addition it provides a way to incrementally build advanced LWRs that are optimally designed to couple to S-CO{sub 2} power conversion systems to increase the power cycle efficiency to near 40%.

  8. BWROPT: A multi-cycle BWR fuel cycle optimization code

    Energy Technology Data Exchange (ETDEWEB)

    Ottinger, Keith E.; Maldonado, G. Ivan, E-mail: Ivan.Maldonado@utk.edu

    2015-09-15

    Highlights: • A multi-cycle BWR fuel cycle optimization algorithm is presented. • New fuel inventory and core loading pattern determination. • The parallel simulated annealing algorithm was used for the optimization. • Variable sampling probabilities were compared to constant sampling probabilities. - Abstract: A new computer code for performing BWR in-core and out-of-core fuel cycle optimization for multiple cycles simultaneously has been developed. Parallel simulated annealing (PSA) is used to optimize the new fuel inventory and placement of new and reload fuel for each cycle considered. Several algorithm improvements were implemented and evaluated. The most significant of these are variable sampling probabilities and sampling new fuel types from an ordered array. A heuristic control rod pattern (CRP) search algorithm was also implemented, which is useful for single CRP determinations, however, this feature requires significant computational resources and is currently not practical for use in a full multi-cycle optimization. The PSA algorithm was demonstrated to be capable of significant objective function reduction and finding candidate loading patterns without constraint violations. The use of variable sampling probabilities was shown to reduce runtime while producing better results compared to using constant sampling probabilities. Sampling new fuel types from an ordered array was shown to have a mixed effect compared to random new fuel type sampling, whereby using both random and ordered sampling produced better results but required longer runtimes.

  9. Optimization of the fuel cycle

    International Nuclear Information System (INIS)

    Kidd, S.W.; Balu, K.; Boczar, P.G.; Krebs, W.D.

    1999-01-01

    The nuclear fuel cycle can be optimized subject to a wide range of criteria. Prime amongst these are economics, sustainability of resources, environmental aspects, and proliferation-resistance of the fuel cycle. Other specific national objectives will also be important. These criteria, and their relative importance, will vary from country to country, and with time. There is no single fuel cycle strategy that is optimal for all countries. Within the short term, the industry is attached to dominant thermal reactor technologies, which themselves have two main variants, a cycle closed by reprocessing of spent fuel and subsequent recycling and a once through one where spent fuel is stored in advance of geological disposal. However, even with current technologies, much can be done to optimize the fuel cycles to meet the relevant criteria. In the long term, resource sustainability can be assured for centuries through the use of fast breeder reactors, supporting high-conversion thermal reactors, possibly also utilizing the thorium cycle. These must, however, meet the other key criteria by being both economic and safe. (author)

  10. Changing global carbon cycle

    International Nuclear Information System (INIS)

    Canadell, Pep

    2007-01-01

    Full text: The increase in atmospheric carbon dioxide (C02) is the single largest human perturbation on the earth's radiative balance contributing to climate change. Its rate of change reflects the balance between anthropogenic carbon emissions and the dynamics of a number of terrestrial and ocean processes that remove or emit C02. It is the long term evolution of this balance that will determine to large extent the speed and magnitude of the human induced climate change and the mitigation requirements to stabilise atmospheric C02 concentrations at any given level. In this talk, we show new trends in global carbon sources and sinks, with particularly focus on major shifts occurring since 2000 when the growth rate of atmospheric C02 has reached its highest level on record. The acceleration in the C02 growth results from the combination of several changes in properties of the carbon cycle, including: acceleration of anthropogenic carbon emissions; increased carbon intensity of the global economy, and decreased efficiency of natural carbon sinks. We discuss in more detail some of the possible causes of the reduced efficiency of natural carbon sinks on land and oceans, such as the decreased net sink in the Southern Ocean and on terrestrial mid-latitudes due to world-wide occurrence of drought. All these changes reported here characterise a carbon cycle that is generating stronger than expected climate forcing, and sooner than expected

  11. A study of power cycles using supercritical carbon dioxide as the working fluid

    Science.gov (United States)

    Schroder, Andrew Urban

    A real fluid heat engine power cycle analysis code has been developed for analyzing the zero dimensional performance of a general recuperated, recompression, precompression supercritical carbon dioxide power cycle with reheat and a unique shaft configuration. With the proposed shaft configuration, several smaller compressor-turbine pairs could be placed inside of a pressure vessel in order to avoid high speed, high pressure rotating seals. The small compressor-turbine pairs would share some resemblance with a turbocharger assembly. Variation in fluid properties within the heat exchangers is taken into account by discretizing zero dimensional heat exchangers. The cycle analysis code allows for multiple reheat stages, as well as an option for the main compressor to be powered by a dedicated turbine or an electrical motor. Variation in performance with respect to design heat exchanger pressure drops and minimum temperature differences, precompressor pressure ratio, main compressor pressure ratio, recompression mass fraction, main compressor inlet pressure, and low temperature recuperator mass fraction have been explored throughout a range of each design parameter. Turbomachinery isentropic efficiencies are implemented and the sensitivity of the cycle performance and the optimal design parameters is explored. Sensitivity of the cycle performance and optimal design parameters is studied with respect to the minimum heat rejection temperature and the maximum heat addition temperature. A hybrid stochastic and gradient based optimization technique has been used to optimize critical design parameters for maximum engine thermal efficiency. A parallel design exploration mode was also developed in order to rapidly conduct the parameter sweeps in this design space exploration. A cycle thermal efficiency of 49.6% is predicted with a 320K [47°C] minimum temperature and 923K [650°C] maximum temperature. The real fluid heat engine power cycle analysis code was expanded to study a

  12. A Geometry-Based Cycle Slip Detection and Repair Method with Time-Differenced Carrier Phase (TDCP) for a Single Frequency Global Position System (GPS) + BeiDou Navigation Satellite System (BDS) Receiver

    OpenAIRE

    Qian, Chuang; Liu, Hui; Zhang, Ming; Shu, Bao; Xu, Longwei; Zhang, Rufei

    2016-01-01

    As the field of high-precision applications based on carriers continues to expand, the development of low-cost, small, modular receivers and their application in diverse scenarios and situations with complex data quality has increased the requirements of carrier-phase data preprocessing. A new geometry-based cycle slip detection and repair method based on Global Position System (GPS) + BeiDou Navigation Satellite System (BDS) is proposed. The method uses a Time-differenced Carrier Phase (TDCP...

  13. Re-austenitisation of chromium-bearing pressure vessel steels during the weld thermal cycle

    International Nuclear Information System (INIS)

    Dunne, Druce; Li, Huijun; Jones, Christopher

    2013-01-01

    Steels with chromium contents between 0.5 and 12 wt% are commonly used for fabrication of creep resistant pressure vessels (PV) for the power generation industry. Most of these steels are susceptible to Type IV creep failure in the intercritical and/ or grain refined regions of the heat affected zone (HAZ) of the parent metal. The re-austenitisation process plays a central role in establishing the transformed microstructures and the creep resistance of the various sub-zones of the HAZ. The high alloy content and the presence of alloy-rich carbides in the as-supplied parent plate can significantly retard the kinetics of transformation to austenite, resulting in both incomplete austenitisation and inhomogeneous austenite. Overlapping weld thermal cycles in multi-pass welds add further complexity to the progressive development of microstructure over the course of the welding process. In order to clarify structural evolution, thermal simulation has been used to study the effects of successive thermal cycles on the structures and properties of the HAZ of 2.25Cr-1Mo steel. The results showed that, before post-weld heat treatment (PWHT), the HAZ microstructures and properties, particularly in doubly reheated sub-zones, were highly heterogeneous and differed markedly from those of the base steel. It is concluded that close control of the thermal cycle by pre-heat, weld heat input and post-heat is necessary to obtain a heat affected zone with microstructures and properties compatible with those of the base plate.

  14. Innovation and Business Cycles

    OpenAIRE

    Festré, Agnès

    2002-01-01

    The main purpose of this chapter is to assess the originality of Schumpeter's theory of business cycles. The first section outlines the distinctive features of Schumpeter's approach to business cycles and economic dynamics. Section two looks at the mechanisms constituting the cycle in Schumpeter's two major contributions on this subject, the Theory of Economic Development (1911) and Business Cycles (1939).

  15. The fuel cycle

    International Nuclear Information System (INIS)

    2000-01-01

    In this brochure the fuel cycle is presented. The following fuel cycle steps are described: (1) Front of the fuel cycle (Mining and milling; Treatment; Refining, conversion and enrichment; Fuel fabrication); (2) Use of fuel in nuclear reactors; (3) Back end of the fuel cycle (Interim storage of spent fuel; spent fuel reprocessing; Final disposal of spent fuel)

  16. The chromosome cycle of prokaryotes

    Science.gov (United States)

    Kuzminov, Andrei

    2013-01-01

    Summary In both eukaryotes and prokaryotes, chromosomal DNA undergoes replication, condensation-decondensation and segregation, sequentially, in some fixed order. Other conditions, like sister-chromatid cohesion (SCC), may span several chromosomal events. One set of these chromosomal transactions within a single cell cycle constitutes the “chromosome cycle”. For many years it was generally assumed that the prokaryotic chromosome cycle follows major phases of the eukaryotic one: -replication-condensation-segregation-(cell division)-decondensation-, with SCC of unspecified length. Eventually it became evident that, in contrast to the strictly consecutive chromosome cycle of eukaryotes, all stages of the prokaryotic chromosome cycle run concurrently. Thus, prokaryotes practice “progressive” chromosome segregation separated from replication by a brief SCC, and all three transactions move along the chromosome at the same fast rate. In other words, in addition to replication forks, there are “segregation forks” in prokaryotic chromosomes. Moreover, the bulk of prokaryotic DNA outside the replication-segregation transition stays compacted. I consider possible origins of this concurrent replication-segregation and outline the “nucleoid administration” system that organizes the dynamic part of the prokaryotic chromosome cycle. PMID:23962352

  17. Metabolic Interaction between Urea Cycle and Citric Acid Cycle Shunt: A Guided Approach

    Science.gov (United States)

    Pesi, Rossana; Balestri, Francesco; Ipata, Piero L.

    2018-01-01

    This article is a guided pedagogical approach, devoted to postgraduate students specializing in biochemistry, aimed at presenting all single reactions and overall equations leading to the metabolic interaction between ureagenesis and citric acid cycle to be incorporated into a two-three lecture series about the interaction of urea cycle with other…

  18. Monitoring city wide patterns of cycling safety.

    Science.gov (United States)

    Boss, Darren; Nelson, Trisalyn; Winters, Meghan

    2018-02-01

    Many cities are making significant financial investments in cycling infrastructure with the aim of making cycling safer for riders of all ages and abilities. Methods for evaluating cycling safety tend to summarize average change for a city or emphasize change on a single road segment. Few spatially explicit approaches are available to evaluate how patterns of safety change throughout a city due to cycling infrastructure investments or other changes. Our goal is to demonstrate a method for monitoring changes in the spatial-temporal distribution of cycling incidents across a city. Using cycling incident data provided by the Insurance Corporation of British Columbia, we first compare planar versus network constrained kernel density estimation for visualizing incident intensity across the street network of Vancouver, Canada. Second, we apply a change detection algorithm explicitly designed for detecting statistically significant change in kernel density estimates. The utility of network kernel density change detection is demonstrated through the comparison of cycling incident densities following the construction of two cycle tracks in the downtown core of Vancouver. The methods developed and demonstrated for this study provide city planners, transportation engineers and researchers a means of monitoring city-wide change in the intensity of cycling incidents following enhancements to cycling infrastructure or other significant changes to the transportation network. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Proliferation in cycle

    Energy Technology Data Exchange (ETDEWEB)

    Piao Yunsong [College of Physical Sciences, Graduate School of Chinese Academy of Sciences, Beijing 100049 (China)], E-mail: yspiao@gucas.ac.cn

    2009-06-15

    In the contracting phase with w{approx_equal}0, the scale invariant spectrum of curvature perturbation is given by the increasing mode of metric perturbation. In this Letter, it is found that if the contracting phase with w{approx_equal}0 is included in each cycle of a cycle universe, since the metric perturbation is amplified on super horizon scale cycle by cycle, after each cycle the universe will be inevitably separated into many parts independent of one another, each of which corresponds to a new universe and evolves up to next cycle, and then is separated again. In this sense, a cyclic multiverse scenario is actually presented, in which the universe proliferates cycle by cycle. We estimate the number of new universes proliferated in each cycle, and discuss the implications of this result.

  20. Cycling in Sydney, Australia

    Directory of Open Access Journals (Sweden)

    Alexis Zander

    2013-01-01

    Full Text Available Introduction. Cycling can be an enjoyable way to meet physical activity recommendations and is suitable for older people; however cycling participation by older Australians is low. This qualitative study explored motivators, enablers, and barriers to cycling among older people through an age-targeted cycling promotion program. Methods. Seventeen adults who aged 50–75 years participated in a 12-week cycling promotion program which included a cycling skills course, mentor, and resource pack. Semistructured interviews at the beginning and end of the program explored motivators, enablers, and barriers to cycling. Results. Fitness and recreation were the primary motivators for cycling. The biggest barrier was fear of cars and traffic, and the cycling skills course was the most important enabler for improving participants’ confidence. Reported outcomes from cycling included improved quality of life (better mental health, social benefit, and empowerment and improved physical health. Conclusions. A simple cycling program increased cycling participation among older people. This work confirms the importance of improving confidence in this age group through a skills course, mentors, and maps and highlights additional strategies for promoting cycling, such as ongoing improvement to infrastructure and advertising.

  1. Life cycle assessment (LCA)

    DEFF Research Database (Denmark)

    Thrane, Mikkel; Schmidt, Jannick Andresen

    2004-01-01

    The chapter introduces Life Cycle Assessment (LCA) and its application according to the ISO 1404043 standards.......The chapter introduces Life Cycle Assessment (LCA) and its application according to the ISO 1404043 standards....

  2. Thorium fuel cycle management

    International Nuclear Information System (INIS)

    Zajac, R.; Darilek, P.; Breza, J.; Necas, V.

    2010-01-01

    In this presentation author deals with the thorium fuel cycle management. Description of the thorium fuels and thorium fuel cycle benefits and challenges as well as thorium fuel calculations performed by the computer code HELIOS are presented.

  3. Marine nitrogen cycle

    Digital Repository Service at National Institute of Oceanography (India)

    Naqvi, S.W.A.

    of the marine nitrogen cycle and its influence on atmospheric CO 2 , in: The Ocean Carbon Cycle and Climate, edited by: Follows, M., and Oguz, T., Kluwer Academic, Dordrecht, 97-148, 2004. ISBN 1402020864. Citation Naqvi, Syed. 2006. "Marine nitrogen cycle...]. cycle> All text is available under the terms of the Creative Commons Attribution-Share Alike license. Please see the Encyclopedia of Earth's website for Terms of Use information. Supported...

  4. Life Cycle Management

    DEFF Research Database (Denmark)

    Bey, Niki

    2017-01-01

    This chapter gives an overview of Life Cycle Management (LCM)—a discipline that deals with the managerial tasks related to practicing sustainable development in an organisation . Just as Life Cycle Assessment, LCM advocates the life cycle perspective , and it applies this perspective in decision...

  5. Cycling To Awareness.

    Science.gov (United States)

    Kozak, Stan

    1999-01-01

    Encourages environmental and outdoor educators to promote bicycling. In the community and the curriculum, cycling connects environmental issues, health and fitness, law and citizenship, appropriate technology, and the joy of being outdoors. Describes the Ontario Cycling Association's cycling strategy and its four components: school cycling…

  6. Combined-cycle power plant. 500 MW on a single shaft. Active stability improvement of the compressor - methods of analysis. Final report; GuD-Kraftwerk, 500 MW auf einer Welle. Aktive Stabilitaetsverbesserung am Verdichter - Analyseverfahren. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Stoff, H.; Methling, F.O.

    2002-07-01

    Various analysis techniques are tested as possible stall and surge avoidance monitoring systems on high-speed axial compressors. Measurements were taken in a 4-stage transonic compressor with igv in the region of stable operation as well as approaching and crossing the surge line with fully developed rotating stall. The measurements contain the static wall pressure in front of each blade row. Artificial neural networks, Fourier techniques and cepstral analysis are investigated. The different methods are checked on a single sensor signal to reduce the instrumentational effort. Using the cepstral analysis a characteristic parameter is calculated which is valid in all investigated regions of operation of the compressor. This characteristic parameter is based on the blade passing frequency, i.e. in the terms of cepstral analysis it is the intensity of the fundamental component as well as the intensities of all its higher harmonics which are covered by the sensor signal. (orig.)

  7. Fan cycling strategies and heat pipe heat exchangers provide energy efficient dehumidification

    Energy Technology Data Exchange (ETDEWEB)

    Shirey, D.B. III [Florida Solar Energy Center, Cape Canaveral, FL (United States)

    1995-03-01

    This article describes two methods to reduce energy consumption and peak demand in buildings that require humidity control that were demonstrated at the Salvador Dali Museum in St. Petersburg, Florida. The first method centered on alternative indoor fan cycling strategies and the second method involved the use of heat pipe heat exchangers. Both approaches increased the dehumidification performance of the existing air-conditioning systems and provided substantial savings. Simple, low cost alternative fan cycling strategies were used. When possible, auto fan control replaced constant fan operation to avoid excess fan energy consumption, ventilation load and compressor operation. The alternative fan control strategies reduced indoor humidity fluctuations in all zones, and significantly reduced overall humidity levels in the museum lobby and storage area. An HPHX was installed within one of the two gallery RTUs to improve the unit`s dehumidification performance. The passive HPHX significantly reduced electric reheat and compressor operation while maintaining the precise temperature and humidity requirements within the gallery. The second gallery RTU now operates primarily as a back-up unit to the heat pipe-assisted air-conditioning unit.

  8. International Nuclear Fuel Cycle Fact Book

    Energy Technology Data Exchange (ETDEWEB)

    Leigh, I.W.; Patridge, M.D.

    1991-05-01

    As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need has developed for a ready source of information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book was compiled to meet that need. The information contained in the International Nuclear Fuel Cycle Fact Book has been obtained from many unclassified sources: nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECN/NEA activities reports; not reflect any one single source but frequently represent a consolidation/combination of information.

  9. The identification of two Trypanosoma cruzi I genotypes from domestic and sylvatic transmission cycles in Colombia based on a single polymerase chain reaction amplification of the spliced-leader intergenic region

    Directory of Open Access Journals (Sweden)

    Lina Marcela Villa

    2013-11-01

    Full Text Available A single polymerase chain reaction (PCR reaction targeting the spliced-leader intergenic region of Trypanosoma cruzi I was standardised by amplifying a 231 bp fragment in domestic (TcIDOM strains or clones and 450 and 550 bp fragments in sylvatic strains or clones. This reaction was validated using 44 blind coded samples and 184 non-coded T. cruzi I clones isolated from sylvatic triatomines and the correspondence between the amplified fragments and their domestic or sylvatic origin was determined. Six of the nine strains isolated from acute cases suspected of oral infection had the sylvatic T. cruzi I profile. These results confirmed that the sylvatic T. cruzi I genotype is linked to cases of oral Chagas disease in Colombia. We therefore propose the use of this novel PCR reaction in strains or clones previously characterised as T. cruzi I to distinguish TcIDOMfrom sylvatic genotypes in studies of transmission dynamics, including the verification of population selection within hosts or detection of the frequency of mixed infections by both T. cruzi I genotypes in Colombia.

  10. The Solar Cycle

    Directory of Open Access Journals (Sweden)

    David H. Hathaway

    2015-09-01

    Full Text Available The solar cycle is reviewed. The 11-year cycle of solar activity is characterized by the rise and fall in the numbers and surface area of sunspots. A number of other solar activity indicators also vary in association with the sunspots including; the 10.7 cm radio flux, the total solar irradiance, the magnetic field, flares and coronal mass ejections, geomagnetic activity, galactic cosmic ray fluxes, and radioisotopes in tree rings and ice cores. Individual solar cycles are characterized by their maxima and minima, cycle periods and amplitudes, cycle shape, the equatorward drift of the active latitudes, hemispheric asymmetries, and active longitudes. Cycle-to-cycle variability includes the Maunder Minimum, the Gleissberg Cycle, and the Gnevyshev–Ohl (even-odd Rule. Short-term variability includes the 154-day periodicity, quasi-biennial variations, and double-peaked maxima. We conclude with an examination of prediction techniques for the solar cycle and a closer look at cycles 23 and 24.

  11. Structural changes induced by L50P and I61T single mutations of ubiquitin affect cell cycle progression while impairing its regulatory and degradative functions in Saccharomyces cerevisiae.

    Science.gov (United States)

    Doshi, Ankita; Sharma, Mrinal; Prabha, C Ratna

    2017-06-01

    Posttranslational conjugation of ubiquitin to proteins either regulates their function directly or concentration through ubiquitination dependent degradation. High degree of conservation of ubiquitin's sequence implies structural and functional importance of the conserved residues. Ubiquitin gene of Saccharomyces cerevisiae was evolved in vitro by us to study the significance of conserved residues. Present study investigates the structural changes in the protein resulting from the single mutations UbS20F, UbA46S, UbL50P, UbI61T and their functional consequences in the SUB60 strain of S. cerevisiae. Expression of UbL50P and UbI61T decreased Cdc28 protein kinase, enhanced Fus3 levels, caused dosage dependent lethality and at sublethal level produced drastic effects on stress tolerance, protein sorting, protein degradation by ubiquitin fusion degradation pathway and by lysosomes. UbS20F and UbA46S produced insignificant effects over the cells. All four mutations of ubiquitin were incorporated into polyubiquitin. However, polyubiquitination with K63 linkage decreased significantly in cells expressing UbL50P and UbI61T. Structural studies on UbL50P and UbI61T revealed distorted structure with greatly reduced α-helical and elevated β-sheet contents, while UbS20F and UbA46S show mild structural alterations. Our results on functional efficacy of ubiquitin in relation to structural integrity may be useful for designing inhibitors to investigate and modulate eukaryotic cellular dynamics. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Application of the Combined Cycle LWR-Gas Turbine to PWR for NPP Life Extension Safety Upgrade and Improving Economy

    International Nuclear Information System (INIS)

    Kuznetsov, Yu. N.

    2006-01-01

    Currently, some of the most important problem for the nuclear industry are life extension, advance competitiveness and safety of aging LWR NPPs. Based on results of studies performed in the USA (Battelle Memorial Institute) and in Russia (NIKIET), a new power technology, using a combined cycle gas-turbine facility CCGT - LWR, so called TD-Cycle, can significantly help in resolution of some problems of nuclear power industry. The nuclear steam and gas topping cycle is used for re-powering a light water pressurized reactor of PWR or VVER type. An existing NPP is topped with a gas turbine facility with a heat recovery steam generator (HRSG) generating steam from waste heat. The superheated steam of high pressure (P=90-165 bar, T=500-550 C) generated in the HRSG, is expanded in a high pressure (HP) turbine for producing electricity. The HP turbine can work on one shaft with the the gas turbine or at one shaft with intermediate (IP) or low (LP) pressure parts of the main nuclear steam turbine, or with a separate electric generator. The exhausted steam from the HP turbine is injected into the steam mixer where it is mixed with the saturated steam from the NPP steam generator (SG). The mixer is intended to superheat the main nuclear steam and should be characterized by minimum losses during mixing superheated and saturated steam. Steam from the mixer superheated by 20-60 C directs to the existing IP turbine, and then, through a separator-reheater flows into the LP turbine. Feed water re-heaters of LP and HP are actually unchanged in this case. Feed water extraction to the HRSG is supplied after one of LP water heaters. This proposal is intended to re-power existing LWR NPPs. To minimize cost, the IP and LP turbines and electric generator would remain the same. The reactor thermal power and fast neutron flux to the reactor vessel would decrease by 30-50 percent of nominal values. The external peripheral row of fuel elements can be replaced with metal absorber rods to

  13. Driving and engine cycles

    CERN Document Server

    Giakoumis, Evangelos G

    2017-01-01

    This book presents in detail the most important driving and engine cycles used for the certification and testing of new vehicles and engines around the world. It covers chassis and engine-dynamometer cycles for passenger cars, light-duty vans, heavy-duty engines, non-road engines and motorcycles, offering detailed historical information and critical review. The book also provides detailed examples from SI and diesel engines and vehicles operating during various cycles, with a focus on how the engine behaves during transients and how this is reflected in emitted pollutants, CO2 and after-treatment systems operation. It describes the measurement methods for the testing of new vehicles and essential information on the procedure for creating a driving cycle. Lastly, it presents detailed technical specifications on the most important chassis-dynamometer cycles around the world, together with a direct comparison of those cycles.

  14. Alternative fuel cycles

    International Nuclear Information System (INIS)

    Penn, W.J.

    1979-05-01

    Uranium resource utilization and economic considerations provide incentives to study alternative fuel cycles as future options to the PHWR natural uranium cycle. Preliminary studies to define the most favourable alternatives and their possible introduction dates are discussed. The important and uncertain components which influence option selection are reviewed, including nuclear capacity growth, uranium availability and demand, economic potential, and required technological developments. Finally, a summary of Ontario Hydro's program to further assess cycle selection and define development needs is given. (auth)

  15. Measuring Business Cycle Time

    OpenAIRE

    Stock, James H.

    1987-01-01

    The business cycle analysis of Arthur F. Burns and Wesley C. Mitchell and the National Bureau of Economic Research presumed that aggregate economic variables evolve on a time scale defined by business cycle turning points rather than by months or quarters. Do macroeconomic variables appear to evolve on an economic rather than a calendar time scale? Evidence presented here suggests that they do. However, the estimated economic time scales are only weakly related to business cycle time scales, ...

  16. Optimal production of power in a combined cycle from manure based biogas

    International Nuclear Information System (INIS)

    León, Erick; Martín, Mariano

    2016-01-01

    Highlights: • Manure based biogas is a promising renewable source to add value to waste. • Mathematical optimization is used to design a process including gas and steam turbines. • Two schemes for steam production and the effect of animal headcount are compared. • Direct use of flue gas for steam production is recommended. • Digestate economics is key for a competitive price of electricity. - Abstract: In this work, the production of power using a combined cycle gas turbine/steam turbine, which operates with biogas as fuel, is evaluated. The process begins with the production of biogas from pig and/or cattle slurry manure(s) using anaerobic digestion. Afterwards, the gas is cleaned up to remove humidity, hydrogen sulfide, carbon dioxide and ammonia. The cleaned gas (biomethane) is then used in a Brayton cycle (gas turbine) to produce energy. The flue gas that exits the Brayton cycle is typically at high temperature and it is further utilized to produce steam that generates power in a regenerative Rankine cycle (steam turbine). Two alternative steam production schemes are evaluated: either splitting the flue gas to have high temperature gas for the reheating step of the steam or sequential heating up. The model is formulated as a Mixer Integer Nonlinear Programming (MINLP) solved in GAMS® for the optimal production of power. For a typical production capacity of manure in farms, 2.6 MW are produced. The investment for the plant turns out to be 26 M€ and the production cost of the electricity is 0.35 €/kW h before including the credit from the conditioned digestate, that could be sold as fertilizer. The electricity cost goes down to 0.15 €/kW h considering a reasonable credit from the digestate, whose composition depends on the feedstock processed in the facility.

  17. Quantum heating as an alternative of reheating

    Science.gov (United States)

    Akhmedov, Emil T.; Bascone, Francesco

    2018-02-01

    To model a realistic situation for the beginning we consider massive real scalar ϕ4 theory in a (1 +1 )-dimensional asymptotically static Minkowski spacetime with an intermediate stage of expansion. To have an analytic headway we assume that scalars have a big mass. At past and future infinities of the background we have flat Minkowski regions which are joint by the inflationary expansion region. We use the tree-level Keldysh propagator in the theory in question to calculate the expectation value of the stress-energy tensor which is, thus, due to the excitations of the zero-point fluctuations. Then we show that even for large mass, if the de Sitter expansion stage is long enough, the quantum loop corrections to the expectation value of the stress-energy tensor are not negligible in comparison with the tree-level contribution. That is revealed itself via the excitation of the higher-point fluctuations of the exact modes: during the expansion stage a nonzero particle number density for the exact modes is generated. This density is not Planckian and serves as a quench which leads to a thermalization in the out Minkowski stage.

  18. Life Cycle Assessment On Environment

    International Nuclear Information System (INIS)

    Kim, Sang Yong

    1998-04-01

    This book deals with history of life cycle assessment, methodology of life cycle assessment, software system and database, simplification, application of life cycle assessment, life cycle design, calculation of cost of life cycle, application of public policy over life cycle, prospect in Europe, materials in life cycle assessment, application of life cycle assessment in business, system analysis, assessment of value as a state of influence valuation, application of LCA for management situation of solidity waste and view for the future.

  19. Cell cycle entry in C. elegans development

    NARCIS (Netherlands)

    Korzelius, J.P.

    2010-01-01

    Cell division is controlled by a mechanism that uses Cyclins, in association with their Cyclin-dependent kinase partners (Cdk’s), to regulate the transitions in the cell cycle.Studies in mammalian cell culture and single cell eukaryotes such as budding and fission yeast have uncovered much about how

  20. Internally regenerative engine cycle analysis - A parametric study

    Science.gov (United States)

    Keating, E. L.; Pouring, A. A.; Chute, R.

    1983-11-01

    The Air Standard analysis for the internal regenerative Otto and Diesel cycles occurring within a single piston-cylinder geometry was investigated analytically. The use of a constant temperature internal regenerative reservoir permits the absorption of heat from the hot gases and rejection to the cooler charge later in the cycle. A dimensionless analysis to obtain performance predictions for these cycles shows that with regeneration the Otto and Diesel cycles for equal compression ratios can exceed the performance of the corresponding basic cycles. It is also shown that, in certain cases, thermal efficiency and net work output can exceed the basic cycle and that external heat addition may be less than the basic cycle. Performance curves are provided for Otto and Diesel cycle regeneration with fixed Tmax and variable compression ratio.

  1. CANDU combined cycles featuring gas-turbine engines

    International Nuclear Information System (INIS)

    Vecchiarelli, J.; Choy, E.; Peryoga, Y.; Aryono, N.A.

    1998-01-01

    In the present study, a power-plant analysis is conducted to evaluate the thermodynamic merit of various CANDU combined cycles in which continuously operating gas-turbine engines are employed as a source of class IV power restoration. It is proposed to utilize gas turbines in future CANDU power plants, for sites (such as Indonesia) where natural gas or other combustible fuels are abundant. The primary objective is to eliminate the standby diesel-generators (which serve as a backup supply of class III power) since they are nonproductive and expensive. In the proposed concept, the gas turbines would: (1) normally operate on a continuous basis and (2) serve as a reliable backup supply of class IV power (the Gentilly-2 nuclear power plant uses standby gas turbines for this purpose). The backup class IV power enables the plant to operate in poison-prevent mode until normal class IV power is restored. This feature is particularly beneficial to countries with relatively small and less stable grids. Thermodynamically, the advantage of the proposed concept is twofold. Firstly, the operation of the gas-turbine engines would directly increase the net (electrical) power output and the overall thermal efficiency of a CANDU power plant. Secondly, the hot exhaust gases from the gas turbines could be employed to heat water in the CANDU Balance Of Plant (BOP) and therefore improve the thermodynamic performance of the BOP. This may be accomplished via several different combined-cycle configurations, with no impact on the current CANDU Nuclear Steam Supply System (NSSS) full-power operating conditions when each gas turbine is at maximum power. For instance, the hot exhaust gases may be employed for feedwater preheating and steam reheating and/or superheating; heat exchange could be accomplished in a heat recovery steam generator, as in conventional gas-turbine combined-cycle plants. The commercially available GateCycle power plant analysis program was applied to conduct a

  2. Contribution to the improvement of the thermodynamically bind between gas turbine installation and steam turbine installation in power plants with combined steam and gas cycles; Contribution a l'amelioration du couplage thermodynamique entre l'installation de la turbine a gaz et l'installation de la turbine a vapeur dans les centrales electriques a cycles combines gaz/vapeur

    Energy Technology Data Exchange (ETDEWEB)

    Cenusa, V.E.

    2004-10-01

    In 1. chapter is made: a) a presentation of the state of the art in gas turbines (GT) and combined cycles (CC); b) an analyze of CC which use 'H' technologies. The 2. chapter shows the original mathematical model and the computing program of GT, based on sheet data (manufacturer's data). The 3. and 4. chapters show the mathematical models and computing programs for the heat recovery steam generator (HRSG) exergetic optimization with one and two pressure level of steam production, by imposing the total heat transfer area. Into the 5. chapter is made a sensibility analysis of HRSG optimization. The 6. chapter shows the CC optimization with HRSG which have one or two pressure level of steam production without reheating. The final section contents the closing conclusions. (author)

  3. Fatigue diminishes motoneuronal excitability during cycling exercise.

    Science.gov (United States)

    Weavil, Joshua C; Sidhu, Simranjit K; Mangum, Tyler S; Richardson, Russell S; Amann, Markus

    2016-10-01

    Exercise-induced fatigue influences the excitability of the motor pathway during single-joint isometric contractions. This study sought to investigate the influence of fatigue on corticospinal excitability during cycling exercise. Eight men performed fatiguing constant-load (80% W peak ; 241 ± 13 W) cycling to exhaustion during which the percent increase in quadriceps electromyography (ΔEMG; vastus lateralis and rectus femoris) was quantified. During a separate trial, subjects performed two brief (∼45 s) nonfatiguing cycling bouts (244 ± 15 and 331 ± 23W) individually chosen to match the ΔEMG across bouts to that observed during fatiguing cycling. Corticospinal excitability during exercise was quantified by transcranial magnetic, electric transmastoid, and femoral nerve stimulation to elicit motor-evoked potentials (MEP), cervicomedullary evoked potentials (CMEP), and M waves in the quadriceps. Peripheral and central fatigue were expressed as pre- to postexercise reductions in quadriceps twitch force (ΔQ tw ) and voluntary quadriceps activation (ΔVA). Whereas nonfatiguing cycling caused no measureable fatigue, fatiguing cycling resulted in significant peripheral (ΔQ tw : 42 ± 6%) and central (ΔVA: 4 ± 1%) fatigue. During nonfatiguing cycling, the area of MEPs and CMEPs, normalized to M waves, similarly increased in the quadriceps (∼40%; P fatiguing cycling. As a consequence, the ratio of MEP to CMEP was unchanged during both trials (P > 0.5). Therefore, although increases in muscle activation promote corticospinal excitability via motoneuronal facilitation during nonfatiguing cycling, this effect is abolished during fatigue. We conclude that the unaltered excitability of the corticospinal pathway from start of intense cycling exercise to exhaustion is, in part, determined by inhibitory influences on spinal motoneurons obscuring the facilitating effects of muscle activation.

  4. Pipeline bottoming cycle study. Final report

    Energy Technology Data Exchange (ETDEWEB)

    1980-06-01

    The technical and economic feasibility of applying bottoming cycles to the prime movers that drive the compressors of natural gas pipelines was studied. These bottoming cycles convert some of the waste heat from the exhaust gas of the prime movers into shaft power and conserve gas. Three typical compressor station sites were selected, each on a different pipeline. Although the prime movers were different, they were similar enough in exhaust gas flow rate and temperature that a single bottoming cycle system could be designed, with some modifications, for all three sites. Preliminary design included selection of the bottoming cycle working fluid, optimization of the cycle, and design of the components, such as turbine, vapor generator and condensers. Installation drawings were made and hardware and installation costs were estimated. The results of the economic assessment of retrofitting bottoming cycle systems on the three selected sites indicated that profitability was strongly dependent upon the site-specific installation costs, how the energy was used and the yearly utilization of the apparatus. The study indicated that the bottoming cycles are a competitive investment alternative for certain applications for the pipeline industry. Bottoming cycles are technically feasible. It was concluded that proper design and operating practices would reduce the environmental and safety hazards to acceptable levels. The amount of gas that could be saved through the year 2000 by the adoption of bottoming cycles for two different supply projections was estimated as from 0.296 trillion ft/sup 3/ for a low supply projection to 0.734 trillion ft/sup 3/ for a high supply projection. The potential market for bottoming cycle equipment for the two supply projections varied from 170 to 500 units of varying size. Finally, a demonstration program plan was developed.

  5. The Oxygen Cycle.

    Science.gov (United States)

    Swant, Gary D.

    Produced for primary grades, this booklet provides study of the oxygen-carbon dioxide cycle in nature. Line drawings, a minimum amount of narrative, and a glossary of terms make up its content. The booklet is designed to be used as reading material, a coloring book, or for dramatic arts with students acting out parts of the cycle. This work was…

  6. Nutrient cycling strategies.

    NARCIS (Netherlands)

    Breemen, van N.

    1995-01-01

    This paper briefly reviews pathways by which plants can influence the nutrient cycle, and thereby the nutrient supply of themselves and of their competitors. Higher or lower internal nutrient use efficiency positively feeds back into the nutrient cycle, and helps to increase or decrease soil

  7. The carbon cycle revisited

    Science.gov (United States)

    Bolin, Bert; Fung, Inez

    1992-01-01

    Discussions during the Global Change Institute indicated a need to present, in some detail and as accurately as possible, our present knowledge about the carbon cycle, the uncertainties in this knowledge, and the reasons for these uncertainties. We discuss basic issues of internal consistency within the carbon cycle, and end by summarizing the key unknowns.

  8. Seeing the Carbon Cycle

    Science.gov (United States)

    Drouin, Pamela; Welty, David J.; Repeta, Daniel; Engle-Belknap, Cheryl A.; Cramer, Catherine; Frashure, Kim; Chen, Robert

    2006-01-01

    In this article, the authors present a classroom experiment that was developed to introduce middle school learners to the carbon cycle. The experiment deals with transfer of CO[subscript 2] between liquid reservoirs and the effect CO[subscript 2] has on algae growth. It allows students to observe the influence of the carbon cycle on algae growth,…

  9. Teaching the Krebs Cycle.

    Science.gov (United States)

    Akeroyd, F. Michael

    1983-01-01

    Outlines a simple but rigorous treatment of the Krebs Cycle suitable for A-level Biology students. The importance of the addition of water molecules in various stages of the cycle is stressed as well as the removal of hydrogen atoms by the oxidizing enzymes. (JN)

  10. Power Plant Cycling Costs

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, N.; Besuner, P.; Lefton, S.; Agan, D.; Hilleman, D.

    2012-07-01

    This report provides a detailed review of the most up to date data available on power plant cycling costs. The primary objective of this report is to increase awareness of power plant cycling cost, the use of these costs in renewable integration studies and to stimulate debate between policymakers, system dispatchers, plant personnel and power utilities.

  11. Life cycle management (LCM)

    DEFF Research Database (Denmark)

    Remmen, Arne; Thrane, Mikkel

    2004-01-01

    The chapter gives an introduction to Life Cycle Management (LCM) and shows how LCM can be practiced in different contexts and at different ambition levels.......The chapter gives an introduction to Life Cycle Management (LCM) and shows how LCM can be practiced in different contexts and at different ambition levels....

  12. Predicting the Sunspot Cycle

    Science.gov (United States)

    Hathaway, David H.

    2009-01-01

    The 11-year sunspot cycle was discovered by an amateur astronomer in 1844. Visual and photographic observations of sunspots have been made by both amateurs and professionals over the last 400 years. These observations provide key statistical information about the sunspot cycle that do allow for predictions of future activity. However, sunspots and the sunspot cycle are magnetic in nature. For the last 100 years these magnetic measurements have been acquired and used exclusively by professional astronomers to gain new information about the nature of the solar activity cycle. Recently, magnetic dynamo models have evolved to the stage where they can assimilate past data and provide predictions. With the advent of the Internet and open data policies, amateurs now have equal access to the same data used by professionals and equal opportunities to contribute (but, alas, without pay). This talk will describe some of the more useful prediction techniques and reveal what they say about the intensity of the upcoming sunspot cycle.

  13. Large-scale fuel cycle centres

    International Nuclear Information System (INIS)

    Smiley, S.H.; Black, K.M.

    1977-01-01

    The US Nuclear Regulatory Commission (NRC) has considered the nuclear energy centre concept for fuel cycle plants in the Nuclear Energy Centre Site Survey 1975 (NECSS-75) Rep. No. NUREG-0001, an important study mandated by the US Congress in the Energy Reorganization Act of 1974 which created the NRC. For this study, the NRC defined fuel cycle centres as consisting of fuel reprocessing and mixed-oxide fuel fabrication plants, and optional high-level waste and transuranic waste management facilities. A range of fuel cycle centre sizes corresponded to the fuel throughput of power plants with a total capacity of 50,000-300,000MW(e). The types of fuel cycle facilities located at the fuel cycle centre permit the assessment of the role of fuel cycle centres in enhancing the safeguard of strategic special nuclear materials - plutonium and mixed oxides. Siting fuel cycle centres presents a smaller problem than siting reactors. A single reprocessing plant of the scale projected for use in the USA (1500-2000t/a) can reprocess fuel from reactors producing 50,000-65,000MW(e). Only two or three fuel cycle centres of the upper limit size considered in the NECSS-75 would be required in the USA by the year 2000. The NECSS-75 fuel cycle centre evaluation showed that large-scale fuel cycle centres present no real technical siting difficulties from a radiological effluent and safety standpoint. Some construction economies may be achievable with fuel cycle centres, which offer opportunities to improve waste-management systems. Combined centres consisting of reactors and fuel reprocessing and mixed-oxide fuel fabrication plants were also studied in the NECSS. Such centres can eliminate shipment not only of Pu but also mixed-oxide fuel. Increased fuel cycle costs result from implementation of combined centres unless the fuel reprocessing plants are commercial-sized. Development of Pu-burning reactors could reduce any economic penalties of combined centres. The need for effective fissile

  14. Thermodynamic performance simulation and design optimisation of trilateral-cycle engines for waste heat recovery-to-power generation

    International Nuclear Information System (INIS)

    Ajimotokan, H.A.; Sher, I.

    2015-01-01

    Highlights: • Steady-state models of trilateral cycle (TLC) power plants are established and implemented. • Thermodynamic performance simulation and design optimisation of the TLCs are conducted. • Four configurations of the TLCs are analysed and compared their performance metrics. • Results show that thermal integration of the simple TLC enhanced energy conversion efficiency. • Comparative study shows that the recuperated TLC achieved the best performance metrics. - Abstract: The trilateral cycle (TLC) is one of the most promising alternatives among the heat recovery-to-power technologies, due to its compact system configuration and high performance at relatively low compression work and low-to-moderate expander inlet temperature. These feats make the TLC beneficial for off-grid applications particularly in remote or offshore applications where power-to-weight ratio of the power plant is of significance. This study presents the thermodynamic performance simulation and design optimisation of the TLCs using unconventional working fluid for heat recovery-to-power generation from low-grade waste heat, which is considered for process development and integration of the TLC. Four system configurations, comprising the simple TLC, recuperated TLC, reheat TLC and regenerative TLC are analysed and compared their performance metrics. Based on the theory of steady-state steady-flow thermodynamics, the simulation models of the TLC power plants, corresponding to their thermodynamic processes are established and implemented using engineering equation solver. The results show that the thermal efficiencies of the simple TLC, recuperated TLC, reheat TLC and regenerative TLC employing n-pentane are 11.85–21.97%, 12.32–23.91%, 11.86–22.07% and 12.01–22.9% respectively at subcritical operating conditions with low-grade heat in the temperature limit of 393–473 K. These suggest that the thermal integration of the optimised design of the simple TLC enhanced heat

  15. Watching single molecules dance

    Science.gov (United States)

    Mehta, Amit Dinesh

    Molecular motors convert chemical energy, from ATP hydrolysis or ion flow, into mechanical motion. A variety of increasingly precise mechanical probes have been developed to monitor and perturb these motors at the single molecule level. Several outstanding questions can be best approached at the single molecule level. These include: how far does a motor progress per energy quanta consumed? how does its reaction cycle respond to load? how many productive catalytic cycles can it undergo per diffusional encounter with its track? and what is the mechanical stiffness of a single molecule connection? A dual beam optical trap, in conjunction with in vitro ensemble motility assays, has been used to characterize two members of the myosin superfamily: muscle myosin II and chick brain myosin V. Both move the helical polymer actin, but myosin II acts in large ensembles to drive muscle contraction or cytokinesis, while myosin V acts in small numbers to transport vesicles. An optical trapping apparatus was rendered sufficiently precise to identify a myosin working stroke with 1nm or so, barring systematic errors such as those perhaps due to random protein orientations. This and other light microscopic motility assays were used to characterize myosin V: unlike myosin II this vesicle transport protein moves through many increments of travel while remaining strongly bound to a single actin filament. The step size, stall force, and travel distance of myosin V reveal a remarkably efficient motor capable of moving along a helical track for over a micrometer without significantly spiraling around it. Such properties are fully consistent with the putative role of an organelle transport motor, present in small numbers to maintain movement over long ranges relative to cellular size scales. The contrast between myosin II and myosin V resembles that between a human running on the moon and one walking on earth, where the former allows for faster motion when in larger ensembles but for less

  16. Aquatic cycling-What do we know? A scoping review on head-out aquatic cycling.

    Directory of Open Access Journals (Sweden)

    Stefanie Rewald

    Full Text Available Over the past few years, aquatic cycling has become a trending fitness activity. However, the literature has not been reviewed exhaustively. Therefore, using scoping review methodology, the aim of this review was to explore the current state of the literature concerning aquatic cycling. This study specifically focused on study designs, populations and outcomes. A comprehensive search of seven databases (PubMed, MEDLINE, Cinahl, Embase, PEDro,Web of Science, WorldCat was conducted up to 30th September 2016. GoogleScholar, World Cat, ResearchGate, specific aquatic therapy websites and aquatic therapy journals were searched to identify additional literature. Full-text publications in English, German or Dutch were included. Studies were included when the intervention involved head-out cycling carried out in 10° to 35° Celsius water. Exclusion criteria were the use of wet suits or confounding interventions that would affect participants' homeostasis. 63 articles were included and the study parameters of these studies were summarized. Using three grouping themes, included studies were categorised as 1 single session tests comparing aquatic versus land cycling, or 2 aquatic cycling only sessions investigating different exercise conditions and 3 aquatic cycling intervention programmes. Although the experimental conditions differed noticeably across the studies, shared characteristics were identified. Cardiovascular parameters were investigated by many of the studies with the results suggesting that the cardiac demand of aquatic cycling seems similar to land-based cycling. Only six studies evaluated the effect of aquatic cycling interventions. Therefore, future research should investigate the effects of aquatic cycling interventions, preferably in individuals that are expected to gain health benefits from aquatic cycling. Moreover, this comprehensive outline of available literature could serve as a starting point for systematic reviews or clinical

  17. Aquatic cycling-What do we know? A scoping review on head-out aquatic cycling.

    Science.gov (United States)

    Rewald, Stefanie; Mesters, Ilse; Lenssen, Antoine F; Bansi, Jens; Lambeck, Johan; de Bie, Rob A; Waller, Benjamin

    2017-01-01

    Over the past few years, aquatic cycling has become a trending fitness activity. However, the literature has not been reviewed exhaustively. Therefore, using scoping review methodology, the aim of this review was to explore the current state of the literature concerning aquatic cycling. This study specifically focused on study designs, populations and outcomes. A comprehensive search of seven databases (PubMed, MEDLINE, Cinahl, Embase, PEDro,Web of Science, WorldCat) was conducted up to 30th September 2016. GoogleScholar, World Cat, ResearchGate, specific aquatic therapy websites and aquatic therapy journals were searched to identify additional literature. Full-text publications in English, German or Dutch were included. Studies were included when the intervention involved head-out cycling carried out in 10° to 35° Celsius water. Exclusion criteria were the use of wet suits or confounding interventions that would affect participants' homeostasis. 63 articles were included and the study parameters of these studies were summarized. Using three grouping themes, included studies were categorised as 1) single session tests comparing aquatic versus land cycling, or 2) aquatic cycling only sessions investigating different exercise conditions and 3) aquatic cycling intervention programmes. Although the experimental conditions differed noticeably across the studies, shared characteristics were identified. Cardiovascular parameters were investigated by many of the studies with the results suggesting that the cardiac demand of aquatic cycling seems similar to land-based cycling. Only six studies evaluated the effect of aquatic cycling interventions. Therefore, future research should investigate the effects of aquatic cycling interventions, preferably in individuals that are expected to gain health benefits from aquatic cycling. Moreover, this comprehensive outline of available literature could serve as a starting point for systematic reviews or clinical studies on the

  18. The distribution of events in the human menstrual cycle.

    Science.gov (United States)

    Udry, J R; Morris, N M

    1977-11-01

    Daily reports of 85 married couples concerning their sexual behaviour for about 3 menstrual cycles per couple were organized according to menstrual events by using six techniques of aggregation. While there were some similarities among the different displays, including an apparent peak about 6 days before mid-cycle, different methods of aggregation produce widely different frequency curves. It is concluded that there is no single method of display of events of the menstrual cycle which will fit all investigations.

  19. Two Quantum Polytropic Cycles

    Science.gov (United States)

    Arias-Hernández, L. A.; Morales-Serrano, A. F.

    2002-11-01

    In this work we follow the Bender et al paper [1] to study the quantum analogues of the Stirling and Ericsson polytropic cycles. In the context of the classical thermodynamics, the Stirling and Ericsson cycles correspond to reversible heat engines with two isothermal processes joined by two polytropic branches which occur in a device called regenerator. If this device is an ideal one, the efficiency of these cycles is the Carnot efficiency. Here, we introduce the quantum analogues of the Stirling and Ericsson cycles, the first one based on a double square potential well with a finite potential barrier, since in this system the tunnel effect could be the analogue to the regeneration classical process, therefore the isochoric quantum branches would really correspond to an internal energy storage, and the last one with an unknown system where the isobaric quantum processes don't induce changes in its quantum state. With these systems the quantum engines have cycles consisting of polytropic and isothermal quantum processes analogues to the corresponding classical processes. We show that in both cases the quantum cycles have an efficiency given by ηCQM = 1 - EC/EH, which is the same expression for the quantum analogue of the Carnot cycle studied by Bender.

  20. Fuel cycle management

    International Nuclear Information System (INIS)

    Herbin, H.C.

    1977-01-01

    The fuel cycle management is more and more dependent on the management of the generation means among the power plants tied to the grid. This is due mainly because of the importance taken by the nuclear power plants within the power system. The main task of the fuel cycle management is to define the refuelling pattern of the new and irradiated fuel assemblies to load in the core as a function of: 1) the differences which exist between the actual conditions of the core and what was expected for the present cycle, 2) the operating constraints and the reactor availability, 3) the technical requirements in safety and the technological limits of the fuel, 4) the economics. Three levels of fuel cycle management can be considered: 1) a long term management: determination of enrichments and expected cycle lengths, 2) a mid term management whose aim corresponds to the evaluation of the batch to load within the core as a function of both: the next cycle length to achieve and the integrated power history of all the cycles up to the present one, 3) a short term management which deals with the updating of the loaded fuel utilisations to take into account the operation perturbations, or with the alteration of the loading pattern of the next batch to respect unexpected conditions. (orig.) [de

  1. Future fuel cycles

    International Nuclear Information System (INIS)

    Archinoff, G.H.

    1980-01-01

    A fuel cycle must offer both financial and resource savings if it is to be considered for introduction into Ontario's nuclear system. The most promising alternative CANDU fuel cycles are examined in the context of both of these factors over a wide range of installed capacity growth rates and economic assumptions, in order to determine which fuel cycle, or cycles, should be introduced, and when. It is concluded that the optimum path for the long term begins with the prompt introduction of the low-enriched-uranium fuel cycle. For a wide range of conditions, this cycle remains the optimum throughout the very long term. Conditions of rapid nuclear growth and very high uranium price escalation rates warrant the supersedure of the low-enriched-uranium cycle by either a plutonium-topped thorium cycle or plutonium recycle, beginning between 2010 and 2025. It is also found that the uranium resource position is sound in terms of both known resources and production capability. Moreover, introduction of the low-enriched-uranium fuel cycle and 1250 MWe reactor units will assure the economic viability of nuclear power until at least 2020, even if uranium prices increase at a rate of 3.5% above inflation. The interrelationship between these two conclusions lies in the tremendous incentive for exploration which will occur if the real uranium price escalation rate is high. From a competitive viewpoint, nuclear power can withstand increases in the price of uranium. However, such increases will likely further expand the resource base, making nuclear an even more reliable energy source. (auth)

  2. Optimizing design of converters using power cycling lifetime models

    DEFF Research Database (Denmark)

    Nielsen, Rasmus Ørndrup; Munk-Nielsen, Stig

    2015-01-01

    Converter power cycling lifetime depends heavily on converter operation point. A lifetime model of a single power module switched mode power supply with wide input voltage range is shown. A lifetime model is created using a power loss model, a thermal model and a model for power cycling capability...

  3. Thermodynamic analysis of a novel integrated solar combined cycle

    International Nuclear Information System (INIS)

    Li, Yuanyuan; Yang, Yongping

    2014-01-01

    Highlights: • A novel ISCC scheme with two-stage DSG fields has been proposed and analyzed. • HRSG and steam turbine working parameters have been optimized to match the solar integration. • New scheme exhibits higher solar shares in the power output and solar-to-electricity efficiency. • Thermodynamic performances between new and reference systems have been investigated and compared. - Abstract: Integrated solar combined cycle (ISCC) systems have become more and more popular due to their high fuel and solar energy utilization efficiencies. Conventional ISCC systems with direct steam generation (DSG) have only one-stage solar input. A novel ISCC with DSG system has been proposed and analyzed in this paper. The new system consists two-stage solar input, which would significantly increase solar share in the total power output. Moreover, how and where solar energy is input into ISCC system would have impact on the solar and system overall efficiencies, which have been analyzed in the paper. It has been found that using solar heat to supply latent heat for vaporization of feedwater would be superior to that to be used for sensible heating purposes (e.g. Superheating steam). The study shows that: (1) producing both the high- and low-pressure saturated steam in the DSG trough collector could be an efficient way to improve process and system performance; (2) for a given live steam pressure, the optimum secondary and reheat steam conditions could be matched to reach the highest system thermal efficiency and net solar-to-electricity efficiency; (3) the net solar-to-electricity efficiency could reach up to 30% in the novel two-stage ISCC system, higher than that in the one-stage ISCC power plant; (4) compared with the conventional combined cycle gas turbine (CCGT) power system, lower stack temperature could be achieved, owing to the elimination of the approach-temperature-difference constraint, resulting in better thermal match in the heat recovery steam generator

  4. Single-cycle Optical Pulses and Isolated Attosecond Pulse Generation

    Science.gov (United States)

    2012-02-29

    A. H. Curtis, S. P. Meehan, and J . J . Rocca , “Demonstration of all-diode-pumped soft x-ray laser,” Opt. Lett. 34, 3352 (2009). 40. K.-H. Hong, J ...Feb. 2012): <Journal paper> 1) J . Moses, C. Manzoni, S-W Huang, G.Cerullo, and F. X. Kärtner, “Temporal Optimization of Ultrabroadband High-Energy...OPCPA,” Opt. Express 17, 5540 (Mar, 2009). 2) J . Moses, S.-W. Huang, K.-H. Hong, O. D. Mücke, E. L. Falcão-Filho, A. Benedick, F. Ö. Ilday, A

  5. Product Life Cycle Planning

    National Research Council Canada - National Science Library

    Walaszek, Jeffrey

    2003-01-01

    .... This phase of work was undertaken to: (1) provide guidelines, technical support, and planning approaches for researchers that result in realistic life cycle plans for products emerging from the RSM...

  6. Cycles in graphs

    CERN Document Server

    Alspach, BR

    1985-01-01

    This volume deals with a variety of problems involving cycles in graphs and circuits in digraphs. Leading researchers in this area present here 3 survey papers and 42 papers containing new results. There is also a collection of unsolved problems.

  7. Fuel cycle studies

    International Nuclear Information System (INIS)

    Anon.

    1978-01-01

    Programs are being conducted in the following areas: advanced solvent extraction techniques, accident consequences, fuel cycles for nonproliferation, pyrochemical and dry processes, waste encapsulation, radionuclide transport in geologic media, hull treatment, and analytical support for LWBR

  8. Educational Business Cycles

    DEFF Research Database (Denmark)

    Tepe, Markus; Vanhuysse, Pieter

    2009-01-01

    Strong institutional constraints and better-informed voters may lead re-election seeking incumbents to shift the use of political business cycle mechanisms away from monetary and fiscal policy towards other policy domains that are more easily manipulable, targetable, and timeable. We investigate...... teacher employment patterns at the state level in Germany and find strong evidence of cycling mechanisms, in the form of electioneering and honeymooning. Against a backdrop of a continuously shrinking total teachers' pool, German state-level incumbents accelerate the hiring of new teachers during election...... periods and partly reverse this during politically safer points in the electoral cycle. Cycles are mediated by issue salience: heightened attention to German public schooling after the notorious PISA-2000 tests further strengthens the manipulation of new teacher hiring for electoral purposes....

  9. Educational Business Cycles

    DEFF Research Database (Denmark)

    Tepe, Markus; Vanhuysse, Pieter

    Strong institutional constraints and better-informed voters may lead re-election seeking incumbents to shift the use of political business cycle mechanisms away from monetary and fiscal policy towards other policy domains that are more easily manipulable, targetable, and timeable. We investigate...... teacher employment patterns at the state level in Germany and find strong evidence of cycling mechanisms, in the form of electioneering and honeymooning. Against a backdrop of a continuously shrinking total teachers' pool, German state-level incumbents accelerate the hiring of new teachers during election...... periods and partly reverse this during politically safer points in the electoral cycle. Cycles are mediated by issue salience: heightened attention to German public schooling after the notorious PISA-2000 tests further strengthens the manipulation of new teacher hiring for electoral purposes....

  10. Traffic Signal Cycle Lengths

    Data.gov (United States)

    Town of Chapel Hill, North Carolina — Traffic signal location list for the town of Chapel Hill. This data set includes light cycle information as well as as intersection information.The Town of Chapel...

  11. IFR fuel cycle

    International Nuclear Information System (INIS)

    Battles, J.E.; Miller, W.E.; Lineberry, M.J.; Phipps, R.D.

    1992-01-01

    The next major milestone of the IFR program is engineering-scale demonstration of the pyroprocess fuel cycle. The EBR-II Fuel Cycle Facility has just entered a startup phase, which includes completion of facility modifications and installation and cold checkout of process equipment. This paper reviews the development of the electrorefining pyroprocess, the design and construction of the facility for the hot demonstration, the design and fabrication of the equipment, and the schedule and initial plan for its operation

  12. The global carbon cycle

    International Nuclear Information System (INIS)

    Maier-Reimer, E.

    1991-01-01

    Basic concepts of the global carbon cycle on earth are described; by careful analyses of isotopic ratios, emission history and oceanic ventilation rates are derived, which provide crucial tests for constraining and calibrating models. Effects of deforestation, fertilizing, fossil fuel burning, soil erosion, etc. are quantified and compared, and the oceanic carbon process is evaluated. Oceanic and terrestrial biosphere modifications are discussed and a carbon cycle model is proposed

  13. Solar Cycle Predictions

    Science.gov (United States)

    Pesnell, William Dean

    2012-01-01

    Solar cycle predictions are needed to plan long-term space missions; just like weather predictions are needed to plan the launch. Fleets of satellites circle the Earth collecting many types of science data, protecting astronauts, and relaying information. All of these satellites are sensitive at some level to solar cycle effects. Predictions of drag on LEO spacecraft are one of the most important. Launching a satellite with less propellant can mean a higher orbit, but unanticipated solar activity and increased drag can make that a Pyrrhic victory as you consume the reduced propellant load more rapidly. Energetic events at the Sun can produce crippling radiation storms that endanger all assets in space. Solar cycle predictions also anticipate the shortwave emissions that cause degradation of solar panels. Testing solar dynamo theories by quantitative predictions of what will happen in 5-20 years is the next arena for solar cycle predictions. A summary and analysis of 75 predictions of the amplitude of the upcoming Solar Cycle 24 is presented. The current state of solar cycle predictions and some anticipations how those predictions could be made more accurate in the future will be discussed.

  14. Quantifying the Adaptive Cycle.

    Directory of Open Access Journals (Sweden)

    David G Angeler

    Full Text Available The adaptive cycle was proposed as a conceptual model to portray patterns of change in complex systems. Despite the model having potential for elucidating change across systems, it has been used mainly as a metaphor, describing system dynamics qualitatively. We use a quantitative approach for testing premises (reorganisation, conservatism, adaptation in the adaptive cycle, using Baltic Sea phytoplankton communities as an example of such complex system dynamics. Phytoplankton organizes in recurring spring and summer blooms, a well-established paradigm in planktology and succession theory, with characteristic temporal trajectories during blooms that may be consistent with adaptive cycle phases. We used long-term (1994-2011 data and multivariate analysis of community structure to assess key components of the adaptive cycle. Specifically, we tested predictions about: reorganisation: spring and summer blooms comprise distinct community states; conservatism: community trajectories during individual adaptive cycles are conservative; and adaptation: phytoplankton species during blooms change in the long term. All predictions were supported by our analyses. Results suggest that traditional ecological paradigms such as phytoplankton successional models have potential for moving the adaptive cycle from a metaphor to a framework that can improve our understanding how complex systems organize and reorganize following collapse. Quantifying reorganization, conservatism and adaptation provides opportunities to cope with the intricacies and uncertainties associated with fast ecological change, driven by shifting system controls. Ultimately, combining traditional ecological paradigms with heuristics of complex system dynamics using quantitative approaches may help refine ecological theory and improve our understanding of the resilience of ecosystems.

  15. Quantifying the adaptive cycle

    Science.gov (United States)

    Angeler, David G.; Allen, Craig R.; Garmestani, Ahjond S.; Gunderson, Lance H.; Hjerne, Olle; Winder, Monika

    2015-01-01

    The adaptive cycle was proposed as a conceptual model to portray patterns of change in complex systems. Despite the model having potential for elucidating change across systems, it has been used mainly as a metaphor, describing system dynamics qualitatively. We use a quantitative approach for testing premises (reorganisation, conservatism, adaptation) in the adaptive cycle, using Baltic Sea phytoplankton communities as an example of such complex system dynamics. Phytoplankton organizes in recurring spring and summer blooms, a well-established paradigm in planktology and succession theory, with characteristic temporal trajectories during blooms that may be consistent with adaptive cycle phases. We used long-term (1994–2011) data and multivariate analysis of community structure to assess key components of the adaptive cycle. Specifically, we tested predictions about: reorganisation: spring and summer blooms comprise distinct community states; conservatism: community trajectories during individual adaptive cycles are conservative; and adaptation: phytoplankton species during blooms change in the long term. All predictions were supported by our analyses. Results suggest that traditional ecological paradigms such as phytoplankton successional models have potential for moving the adaptive cycle from a metaphor to a framework that can improve our understanding how complex systems organize and reorganize following collapse. Quantifying reorganization, conservatism and adaptation provides opportunities to cope with the intricacies and uncertainties associated with fast ecological change, driven by shifting system controls. Ultimately, combining traditional ecological paradigms with heuristics of complex system dynamics using quantitative approaches may help refine ecological theory and improve our understanding of the resilience of ecosystems.

  16. Cycle improvement for nuclear steam power plant

    International Nuclear Information System (INIS)

    Silvestri, G.J. Jr.

    1976-01-01

    A pressure-increasig ejector element is disposed in an extraction line intermediate to a high pressure turbine element and a feedwater heater. The ejector utilizes high pressure fluid from a reheater drain as the motive fluid to increase the pressure at which the extraction steam is introduced into the feedwater heater. The increase in pressure of the extraction steam entering the feedwater heater due to the steam passage through the ejector increases the heat exchange capability of the extraction steam thus increasing the overall steam power plant efficiency

  17. Rapid Cycling and Its Treatment

    Science.gov (United States)

    ... Important security updates for DBSAlliance.org. Read more... Rapid Cycling and its Treatment What is bipolar disorder? ... Guide to Depression and Manic Depression . What is rapid cycling? Rapid cycling is defined as four or ...

  18. The Effect of Cycling Intensity on Cycling Economy During Seated and Standing Cycling.

    Science.gov (United States)

    Arkesteijn, Marco; Jobson, Simon; Hopker, James; Passfield, Louis

    2016-10-01

    Previous research has shown that cycling in a standing position reduces cycling economy compared with seated cycling. It is unknown whether the cycling intensity moderates the reduction in cycling economy while standing. The aim was to determine whether the negative effect of standing on cycling economy would be decreased at a higher intensity. Ten cyclists cycled in 8 different conditions. Each condition was either at an intensity of 50% or 70% of maximal aerobic power at a gradient of 4% or 8% and in the seated or standing cycling position. Cycling economy and muscle activation level of 8 leg muscles were recorded. There was an interaction between cycling intensity and position for cycling economy (P = .03), the overall activation of the leg muscles (P = .02), and the activation of the lower leg muscles (P = .05). The interaction showed decreased cycling economy when standing compared with seated cycling, but the difference was reduced at higher intensity. The overall activation of the leg muscles and the lower leg muscles, respectively, increased and decreased, but the differences between standing and seated cycling were reduced at higher intensity. Cycling economy was lower during standing cycling than seated cycling, but the difference in economy diminishes when cycling intensity increases. Activation of the lower leg muscles did not explain the lower cycling economy while standing. The increased overall activation, therefore, suggests that increased activation of the upper leg muscles explains part of the lower cycling economy while standing.

  19. Life Cycle Assessment of Concrete

    Energy Technology Data Exchange (ETDEWEB)

    Sjunnesson, Jeannette

    2005-09-15

    This is an environmental study on concrete that follows the standard protocol of life cycle assessment (LCA). The study is done for two types of concrete, ordinary and frost-resistant concrete, and has an extra focus on the superplasticizers used as admixtures. The utilization phase is not included in this study since the type of construction for which the concrete is used is not defined and the concrete is assumed to be inert during this phase. The results show that it is the production of the raw material and the transports involved in the life cycle of concrete that are the main contributors to the total environmental load. The one single step in the raw material production that has the highest impact is the production of cement. Within the transportation operations the transportation of concrete is the largest contributor, followed by the transportation of the cement. The environmental impact of frost-resistant concrete is between 24-41 % higher than that of ordinary concrete due to its higher content of cement. Superplasticizers contribute with approximately 0.4-10.4 % of the total environmental impact of concrete, the least to the global warming potential (GWP) and the most to the photochemical ozone creation potential (POCP). Also the toxicity of the superplasticizers is investigated and the conclusion is that the low amount of leakage of superplasticizers from concrete leads to a low risk for the environment and for humans.

  20. Chronoamperometry-Based Redox Cycling for Application to Immunoassays.

    Science.gov (United States)

    Lee, Ga-Yeon; Park, Jun-Hee; Chang, Young Wook; Cho, Sungbo; Kang, Min-Jung; Pyun, Jae-Chul

    2018-01-26

    In this work, the chronoamperometry-based redox cycling of 3,3',5,5'-tetramethylbenzidine (TMB) was performed by using interdigitated electrode (IDE). The signal was obtained from two sequential chronoamperometric profiles: (1) with the generator at the oxidative potential of TMB and the collector at the reductive potential of TMB, and (2) with the generator at the reductive potential of TMB and the collector at the oxidative potential of TMB. The chronoamperometry-based redox cycling (dual mode) showed a sensitivity of 1.49 μA/OD, and the redox cycling efficiency was estimated to be 94% (n = 10). The sensitivities of conventional redox cycling with the same interdigitated electrode and chronoamperometry using a single working electrode (single mode) were estimated to be 0.67 μA/OD and 0.18 μA/OD, respectively. These results showed that the chronoamperometry-based redox cycling (dual mode) could be more effectively used to quantify the oxidized TMB than other amperometric methods. The chronoamperometry-based redox cycling (dual mode) was applied to immunoassays using a commercial ELISA kit for medical diagnosis of the human hepatitis B virus surface antigen (hHBsAg). Finally, the chronoamperometry-based redox cycling (dual mode) provided more than a 10-fold higher sensitivity than conventional chronoamperometry using a single working electrode (single mode) when applied to a commercial ELISA kit for medical diagnosis of hHBsAg.

  1. Historicising the Hydrosocial Cycle

    Directory of Open Access Journals (Sweden)

    Jeremy J. Schmidt

    2014-02-01

    Full Text Available This paper examines the historical claims made in support of the hydrosocial cycle. In particular, it considers how arguments advancing the hydrosocial cycle make historical claims regarding modernist conceptions of what water is (i.e. H2O and its fit with society. The paper gives special emphasis to the society/nature dualism and to the notion of agency as key sites of contest in arguments regarding the hydrosocial cycle. It finds that, while several versions of the hydrosocial cycle seek to advance a political ecology more sensitive to non-human actions, these same accounts often do not address the robust account of non-human agency in the historical record. Evidence is presented regarding water’s agency amongst late 19th and early 20th century architects of key water management norms in the United States. This evidence troubles accounts of the hydrosocial cycle that critique the US experience and suggests new directions for rethinking the role of historical and institutional norms in water policy.

  2. Cascaded organic rankine cycles for waste heat utilization

    Science.gov (United States)

    Radcliff, Thomas D [Vernon, CT; Biederman, Bruce P [West Hartford, CT; Brasz, Joost J [Fayetteville, NY

    2011-05-17

    A pair of organic Rankine cycle systems (20, 25) are combined and their respective organic working fluids are chosen such that the organic working fluid of the first organic Rankine cycle is condensed at a condensation temperature that is well above the boiling point of the organic working fluid of the second organic Rankine style system, and a single common heat exchanger (23) is used for both the condenser of the first organic Rankine cycle system and the evaporator of the second organic Rankine cycle system. A preferred organic working fluid of the first system is toluene and that of the second organic working fluid is R245fa.

  3. International Nuclear Fuel Cycle Fact Book

    International Nuclear Information System (INIS)

    Leigh, I.W.; Mitchell, S.J.

    1990-01-01

    As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need has developed for a ready source of information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book was compiled to meet that need. The information contained in the International Nuclear Fuel Cycle Fact Book has been obtained from many unclassified sources: nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECD/NEA activities reports; proceedings of conferences and workshops, etc. The data listed do not reflect any one single source but frequently represent a consolidation/combination of information

  4. International Nuclear Fuel Cycle Fact Book

    Energy Technology Data Exchange (ETDEWEB)

    Leigh, I.W.

    1992-05-01

    As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need exists costs for a ready source of information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book has been compiled to meet that need. The information contained in the International Nuclear Fuel Cycle Fact Book has been obtained from many unclassified sources: nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECD/NMEA activities reports; and proceedings of conferences and workshops. The data listed typically do not reflect any single source but frequently represent a consolidation/combination of information.

  5. International nuclear fuel cycle fact book

    International Nuclear Information System (INIS)

    Leigh, I.W.; Lakey, L.T.; Schneider, K.J.; Silviera, D.J.

    1987-01-01

    As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need has developed for a ready source of information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book was compiled to meet that need. The information contained has been obtained from nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECD/NEA activities reports; proceedings of conferences and workshops; and so forth. Sources do not agree completely with each other, and the data listed herein does not reflect any one single source but frequently is a consolidation/combination of information. Lack of space as well as the intent and purpose of the Fact Book limit the given information to that pertaining to the Nuclear Fuel Cycle and to data considered of primary interest or most helpful to the majority of users

  6. International nuclear fuel cycle fact book

    International Nuclear Information System (INIS)

    Leigh, I.W.

    1988-01-01

    As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need has developed for a ready source or information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book was compiled to meet that need. The information contained has been obtained from nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECD/NEA activities reports; proceedings of conferences and workshops; and so forth. Sources do not agree completely with each other, and the data listed herein does not reflect any one single source but frequently is consolidation/combination of information. Lack of space as well as the intent and purpose of the Fact Book limit the given information to that pertaining to the Nuclear Fuel Cycle and to data considered of primary interest or most helpful to the majority of users

  7. International nuclear fuel cycle fact book

    Energy Technology Data Exchange (ETDEWEB)

    Leigh, I.W.

    1988-01-01

    As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need has developed for a ready source or information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book was compiled to meet that need. The information contained has been obtained from nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECD/NEA activities reports; proceedings of conferences and workshops; and so forth. Sources do not agree completely with each other, and the data listed herein does not reflect any one single source but frequently is consolidation/combination of information. Lack of space as well as the intent and purpose of the Fact Book limit the given information to that pertaining to the Nuclear Fuel Cycle and to data considered of primary interest or most helpful to the majority of users.

  8. International Nuclear Fuel Cycle Fact Book

    Energy Technology Data Exchange (ETDEWEB)

    Leigh, I W; Mitchell, S J

    1990-01-01

    As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need has developed for a ready source of information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book was compiled to meet that need. The information contained in the International Nuclear Fuel Cycle Fact Book has been obtained from many unclassified sources: nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECD/NEA activities reports; proceedings of conferences and workshops, etc. The data listed do not reflect any one single source but frequently represent a consolidation/combination of information.

  9. International Nuclear Fuel Cycle Fact Book

    International Nuclear Information System (INIS)

    Leigh, I.W.

    1992-05-01

    As the US Department of Energy (DOE) and DOE contractors have become increasingly involved with other nations in nuclear fuel cycle and waste management cooperative activities, a need exists costs for a ready source of information concerning foreign fuel cycle programs, facilities, and personnel. This Fact Book has been compiled to meet that need. The information contained in the International Nuclear Fuel Cycle Fact Book has been obtained from many unclassified sources: nuclear trade journals and newsletters; reports of foreign visits and visitors; CEC, IAEA, and OECD/NMEA activities reports; and proceedings of conferences and workshops. The data listed typically do not reflect any single source but frequently represent a consolidation/combination of information

  10. CO2 cycle

    Science.gov (United States)

    Titus, Timothy N.; Byrne, Shane; Colaprete, Anthony; Forget, Francois; Michaels, Timothy I.; Prettyman, Thomas H.

    2017-01-01

    This chapter discusses the use of models, observations, and laboratory experiments to understand the cycling of CO2 between the atmosphere and seasonal Martian polar caps. This cycle is primarily controlled by the polar heat budget, and thus the emphasis here is on its components, including solar and infrared radiation, the effect of clouds (water- and CO2-ice), atmospheric transport, and subsurface heat conduction. There is a discussion about cap properties including growth and regression rates, albedos and emissivities, grain sizes and dust and/or water-ice contamination, and curious features like cold gas jets and araneiform (spider-shaped) terrain. The nature of the residual south polar cap is discussed as well as its long-term stability and ability to buffer atmospheric pressures. There is also a discussion of the consequences of the CO2 cycle as revealed by the non-condensable gas enrichment observed by Odyssey and modeled by various groups.

  11. Fuel cycle based safeguards

    International Nuclear Information System (INIS)

    De Montmollin, J.M.; Higinbotham, W.A.; Gupta, D.

    1985-07-01

    In NPT safeguards the same model approach and absolute-quantity inspection goals are applied at present to all similar facilities, irrespective of the State's fuel cycle. There is a continuing interest and activity on the part of the IAEA in new NPT safeguards approaches that more directly address a State's nuclear activities as a whole. This fuel cycle based safeguards system is expected to a) provide a statement of findings for the entire State rather than only for individual facilities; b) allocate inspection efforts so as to reflect more realistically the different categories of nuclear materials in the different parts of the fuel cycle and c) provide more timely and better coordinated information on the inputs, outputs and inventories of nuclear materials in a State. (orig./RF) [de

  12. Political Budget Cycles

    DEFF Research Database (Denmark)

    Aaskoven, Lasse; Lassen, David Dreyer

    2017-01-01

    The political budget cycle—how elections affect government fiscal policy—is one of the most studied subjects in political economy and political science. The key theoretical question is whether incumbent governments can time or structure public finances in ways that improve their chances of reelec......The political budget cycle—how elections affect government fiscal policy—is one of the most studied subjects in political economy and political science. The key theoretical question is whether incumbent governments can time or structure public finances in ways that improve their chances...... on political budget cycles have recently focused on conditions under which such cycles are likely to obtain. Much recent research focuses on subnational settings, allowing comparisons of governments in similar institutional environments, and a consensus on the presences of cycles in public finances...

  13. The nuclear fuel cycle

    International Nuclear Information System (INIS)

    Jones, P.M.S.

    1987-01-01

    This chapter explains the distinction between fissile and fertile materials, examines briefly the processes involved in fuel manufacture and management, describes the alternative nuclear fuel cycles and considers their advantages and disadvantages. Fuel management is usually divided into three stages; the front end stage of production and fabrication, the back end stage which deals with the fuel after it is removed from the reactor (including reprocessing and waste treatment) and the stage in between when the fuel is actually in the reactor. These stages are illustrated and explained in detail. The plutonium fuel cycle and thorium-uranium-233 fuel cycle are explained. The differences between fuels for thermal reactors and fast reactors are explained. (U.K.)

  14. Dynamic Analysis of Fuel Cycle Transitioning

    International Nuclear Information System (INIS)

    Dixon, Brent; Piet, Steve; Shropshire, David; Matthern, Gretchen

    2009-01-01

    This paper examines the time-dependent dynamics of transitioning from a once-through fuel cycle to a closed fuel cycle. The once-through system involves only Light Water Reactors (LWRs) operating on uranium oxide fuel (UOX), while the closed cycle includes both LWRs and fast spectrum reactors (FRs) in either a single-tier system or two-tier fuel system. The single-tier system includes full transuranic recycle in FRs while the two-tier system adds one pass of mixed oxide uranium-plutonium (MOX U-Pu) fuel in the LWR. While the analysis primarily focuses on burner fast reactors, transuranic conversion ratios up to 1.0 are assessed and many of the findings apply to any fuel cycle transitioning from a thermal once-through system to a synergistic thermal-fast recycle system. These findings include uranium requirements for a range of nuclear electricity growth rates, the importance of back end fuel cycle facility timing and magnitude, the impact of employing a range of fast reactor conversion ratios, system sensitivity to used fuel cooling time prior to recycle, impacts on a range of waste management indicators, and projected electricity cost ranges for once-through, single-tier and two-tier systems. The study confirmed that significant waste management benefits can be realized as soon as recycling is initiated, but natural uranium savings are minimal in this century. The use of MOX in LWRs decouples the development of recycle facilities from fast reactor fielding, but also significantly delays and limits fast reactor deployment. In all cases, fast reactor deployment was significantly below than predicted by static equilibrium analyses.

  15. The thorium fuel cycle

    International Nuclear Information System (INIS)

    Merz, E.R.

    1977-01-01

    The utilization of the thorium fuel cycle has long since been considered attractive due to the excellent neutronic characteristics of 233 U, and the widespread and cheap thorium resources. Although the uranium ore as well as the separative work requirements are usually lower for any thorium-based fuel cycle in comparison to present uranium-plutonium fuel cycles of thermal water reactors, interest by nuclear industry has hitherto been marginal. Fast increasing uranium prices, public reluctance against widespread Pu-recycling and expected retardations for the market penetration of fast breeders have led to a reconsideration of the thorium fuel cycle merits. In addition, it could be learned in the meantime that problems associated with reprocessing and waste handling, but particularly with a remote refabrication of 233 U are certainly not appreciably more difficult than for Pu-recycling. This may not only be due to psychological constraints but be based upon technological as well as economical facts, which have been mostly neglected up till now. In order to diversify from uranium as a nuclear energy source it seems to be worthwhile to greatly intensify efforts in the future for closing the Th/ 233 U fuel cycle. HTGR's are particularly promising for economic application. However, further R and D activites should not be solely focussed on this reactor type alone. Light and heavy-water moderated reactors, as well as even fast breeders later on, may just as well take advantage of a demonstrated thorium fuel cycle. A summary is presented of the state-of-the-art of Th/ 233 U-recycling technology and the efforts still necessary to demonstrate this technology all the way through to its industrial application

  16. Cycles in fossil diversity

    Energy Technology Data Exchange (ETDEWEB)

    Rohde, Robert A.; Muller, Richard A.

    2004-10-20

    It is well-known that the diversity of life appears to fluctuate during the course the Phanerozoic, the eon during which hard shells and skeletons left abundant fossils (0-542 Ma). Using Sepkoski's compendium of the first and last stratigraphic appearances of 36380 marine genera, we report a strong 62 {+-} 3 Myr cycle, which is particularly strong in the shorter-lived genera. The five great extinctions enumerated by Raup and Sepkoski may be an aspect of this cycle. Because of the high statistical significance, we also consider contributing environmental factors and possible causes.

  17. Life Cycle Environmental Management

    DEFF Research Database (Denmark)

    Pedersen, Claus Stig; Jørgensen, Jørgen; Pedersen, Morten Als

    1996-01-01

    A precondition for environmentally conscious management is the awareness of the environmental impact potentials created by an industrial company. There is an obvious need for management tools to support the implementation of relevant environmental criteria into the industrial decision making...... processes. The discipline of life cycle environmental management (LCEM) focuses on the incorporation of environmental criteria from the life cycles of products and other company activities into the company management processes. This paper introduces the concept of LCEM as an important element...... of the complete set of environmental objects in an industrial manufacturing company....

  18. Cycling injuries and alcohol.

    Science.gov (United States)

    Airaksinen, Noora K; Nurmi-Lüthje, Ilona S; Kataja, J Matti; Kröger, Heikki P J; Lüthje, Peter M J

    2018-03-03

    Most of the cycling accidents that occur in Finland do not end up in the official traffic accident statistics. Thus, there is minimal information on these accidents and their consequences, particularly in cases in which alcohol was involved. The focus of the present study is on cycling accidents and injuries involving alcohol in particular. Data on patients visiting the emergency department at North Kymi Hospital because of a cycling accident was prospectively collected for two years, from June 1, 2004 to May 31, 2006. Blood alcohol concentration (BAC) was measured on admission with a breath analyser. The severity of the cycling injuries was classified according to the Abbreviated Injury Scale (AIS). A total of 217 cycling accidents occurred. One third of the injured cyclists were involved with alcohol at the time of visiting the hospital. Of these, 85% were males. A blood alcohol concentration of ≥ 1.2 g/L was measured in nearly 90% of all alcohol-related cases. A positive BAC result was more common among males than females (p < 0.001), and head injuries were more common among cyclists where alcohol was involved (AI) (60%) than among sober cyclists (29%) (p < 0.001). Two thirds (64%) of the cyclists with AI were not wearing a bicycle helmet. The figure for serious injuries (MAIS ≥ 3) was similar in both groups. Intoxication with an alcohol level of more than 1.5 g/L and the age of 15 to 24 years were found to be risk factors for head injuries. The mean cost of treatment was higher among sober cyclists than among cyclists with AI (€2143 vs. €1629), whereas in respect of the cost of work absence, the situation was the opposite (€1348 vs. €1770, respectively). Cyclists involved with alcohol were, in most cases, heavily intoxicated and were not wearing a bicycle helmet. Head injuries were more common among these cyclists than among sober cyclists. As cycling continues to increase, it is important to monitor cycling accidents, improve

  19. Global water cycle

    Science.gov (United States)

    Robertson, Franklin; Goodman, Steven J.; Christy, John R.; Fitzjarrald, Daniel E.; Chou, Shi-Hung; Crosson, William; Wang, Shouping; Ramirez, Jorge

    1993-01-01

    This research is the MSFC component of a joint MSFC/Pennsylvania State University Eos Interdisciplinary Investigation on the global water cycle extension across the earth sciences. The primary long-term objective of this investigation is to determine the scope and interactions of the global water cycle with all components of the Earth system and to understand how it stimulates and regulates change on both global and regional scales. Significant accomplishments in the past year are presented and include the following: (1) water vapor variability; (2) multi-phase water analysis; (3) global modeling; and (4) optimal precipitation and stream flow analysis and hydrologic processes.

  20. Investment Price Rigidities and Business Cycles

    OpenAIRE

    Moura, Alban

    2015-01-01

    I incorporate investment price rigidity in a two-sector monetary model of business cycles. Fit to quarterly U.S. time series, the model suggests that price sluggishness in the investment sector is the single most empirically relevant friction to match the data. Sticky investment prices constitute an important propagation mechanism to understand the sources of aggregate fluctuations, the dynamic effects of technology shocks, and the properties of the relative price of investment goods.

  1. Menstrual cycle pattern and fertility

    DEFF Research Database (Denmark)

    Kolstad, Henrik A.; Bonde, Jens Peter; Hjøllund, Niels Henrik

    1999-01-01

    To characterize how the menstrual cycle pattern relates to fertility regardless of potential biases caused by inappropriate coital timing during the menstrual cycle or early embryonal loss.......To characterize how the menstrual cycle pattern relates to fertility regardless of potential biases caused by inappropriate coital timing during the menstrual cycle or early embryonal loss....

  2. Entrepreneurship and the business cycle

    NARCIS (Netherlands)

    Koellinger, Philipp D.; Thurik, A. Roy

    2012-01-01

    We find new empirical regularities in the business cycle in a cross-country panel of 22 OECD countries for the period 1972 to 2007; entrepreneurship Granger-causes the cycles of the world economy. Furthermore, the entrepreneurial cycle is positively affected by the national unemployment cycle. We

  3. without intersecting short cycles

    Indian Academy of Sciences (India)

    2016-08-26

    Aug 26, 2016 ... ... Lecture Workshops · Refresher Courses · Symposia. Home; Journals; Proceedings – Mathematical Sciences; Volume 126; Issue 2. (3, 1)*-Choosability of graphs of nonnegative characteristic without intersecting short cycles. Haihui Zhang. Research Article Volume 126 Issue 2 May 2016 pp 159-165 ...

  4. Life Cycle Collection Management

    Directory of Open Access Journals (Sweden)

    Helen Shenton

    2003-09-01

    Full Text Available Life cycle collection management is a way of taking a long-term approach to the responsible stewardship of the British Library's collections and is one of the Library's strategic strands. It defines the different stages in a collection item's existence over time. These stages range from selection and acquisitions processing, cataloguing and press marking, through to preventive conservation, storage and retrieval. Life cycle collection management seeks to identify the costs of each stage in order to show the economic interdependencies between the phases over time. It thereby aims to demonstrate the long-term consequences of what the library takes into its collections, by making explicit the financial and other implications of decisions made at the beginning of the life cycle for the next 100 plus years. This paper describes the work over the past year at the British Library on this complex and complicated subject. It presents the emerging findings and suggests how it can be used for practical reasons (by individual curators and selectors and for economic, governance and political purposes. The paper describes the next steps in the project, for example, on a predictive data model. The British Library is seeking to benchmark itself against comparable organisations in this area. It intends to work with others on specific comparison for example, of life cycle costing of electronic and paper journals, as a prelude to eliding digital and 'traditional' formats.

  5. Educational Business Cycles

    DEFF Research Database (Denmark)

    Tepe, Markus; Vanhuysse, Pieter

    2009-01-01

    teacher employment patterns at the state level in Germany and find strong evidence of cycling mechanisms, in the form of electioneering and honeymooning. Against a backdrop of a continuously shrinking total teachers' pool, German state-level incumbents accelerate the hiring of new teachers during election...

  6. The Degree Cycle

    DEFF Research Database (Denmark)

    Wood, Johanna

    2016-01-01

    The grammaticalization of the demonstratives this, that and thus are investigated with respect to their functions as degree adverbs using empirical data from dictionaries and historical and modern corpora. It is first argued that thus participates in the CP cycle. With respect to this and that, e...

  7. Nuclear fuel cycle

    International Nuclear Information System (INIS)

    1993-01-01

    Status of different nuclear fuel cycle phases in 1992 is discussed including the following issues: uranium exploration, resources, supply and demand, production, market prices, conversion, enrichment; reactor fuel technology; spent fuel management, as well as trends of these phases development up to the year 2010. 10 refs, 11 figs, 15 tabs

  8. Fuel cycle centres

    International Nuclear Information System (INIS)

    Hagen, M.

    1977-01-01

    The concept of co-locating and integrating fuel cycle facilities at one site is discussed. This concept offers considerable advantages, especially in minimizing the amount of radioactive material to be transported on public roads. Safeguards and physical protection as relating to such an integrated system of facilities are analysed in detail, also industrial and commercial questions. An overall risk-benefit evaluation turns out to be in favour of fuel cycle centres. These centres seem to be specifically attractive with regard to the back end of the fuel cycle, including on-site disposal of radioactive wastes. The respective German approach is presented as an example. Special emphasis is given to the site selection procedures in this case. Time scale and cost for the implementation of this concept are important factors to be looked at. Since participation of governmental institutions in these centres seems to be indispensable their respective roles as compared to industry must be clearly defined. The idea of adjusting fuel cycle centres to regional rather than national use might be an attractive option, depending on the specific parameters in the region, though results of existing multinational ventures are inconclusive in this respect. Major difficulties might be expected e.g. because of different national safety regulations and standards as well as commercial conditions among partner countries. Public acceptance in the host country seems to be another stumbling block for the realization of this type of multinational facilities

  9. Re-Cycling

    Science.gov (United States)

    Brown, Robert W.; Covault, Corbin E.

    2015-01-01

    An old comedy routine on Saturday Night Live by Father Guido Sarducci introduced a "Five-Minute University," because five minutes is all that's remembered after graduation anyway. In counterpoint, we discuss "cycling," a teaching method for memory enhancement. Our principal implementation consists of offering a simple version…

  10. The Science of Cycling

    Science.gov (United States)

    Crompton, Zoe; Daniels, Shelley

    2014-01-01

    Children are engaged by finding out about science in the real world (Harlen, 2010). Many children will be cyclists or will have seen or heard about the success of British cyclists in the Olympics and the Tour de France. This makes cycling a good hook to draw children into learning science. It is also a good cross-curricular topic, with strong…

  11. Big Data and Cycling

    NARCIS (Netherlands)

    Romanillos, Gustavo; Zaltz Austwick, Martin; Ettema, Dick; De Kruijf, Joost

    2016-01-01

    Big Data has begun to create significant impacts in urban and transport planning. This paper covers the explosion in data-driven research on cycling, most of which has occurred in the last ten years. We review the techniques, objectives and findings of a growing number of studies we have classified

  12. Cycling in Switzerland

    NARCIS (Netherlands)

    Bernards, R.A.

    1996-01-01

    Progression through the cell cycle is mediated by the sequential activation of a number of cyclins that form active kinase complexes when bound to one of several cyclin-dependent kinases (CDKs). In GI, these kinases phosphorylate, amongst others, the retinoblastoma protein, which, when

  13. Skills, sunspots and cycles

    DEFF Research Database (Denmark)

    Busato, Francesco; Marchetti, Enrico

    This paper explores the ability of a class of one-sector,multi-input models to generate indeterminate equilibrium paths, andendogenous cycles, without relying on factors' hoarding. The modelpresents a novel theoretical economic mechanism that supportssunspot-driven expansions without requiring up...

  14. The plutonium fuel cycles

    International Nuclear Information System (INIS)

    Pigford, T.H.; Ang, K.P.

    1975-01-01

    The quantities of plutonium and other fuel actinides have been calculated for equilibrium fuel cycles for 1000-MW water reactors fueled with slightly enriched uranium, water reactors fueled with plutonium and natural uranium, fast-breder reactors, gas-cooled reactors fueled with thorium and highly enriched uranium, and gas-cooled reactors fueled with thorium, plutonium and recycled uranium. The radioactivity quantities of plutonium, americium and curium processed yearly in these fuel cycles are greatest for the water reactors fueled with natural uranium and recycled plutonium. The total amount of actinides processed is calculated for the predicted future growth of the U.S. nuclear power industry. For the same total installed nuclear power capacity, the introduction of the plutonium breeder has little effect upon the total amount of plutonium in this century. The estimated amount of plutonium in the low-level process wastes in the plutonium fuel cycles is comparable to the amount of plutonium in the high-level fission product wastes. The amount of plutonium processed in the nuclear fuel cycles can be considerably reduced by using gas-cooled reactors to consume plutonium produced in uranium-fueled water reactors. These, and other reactors dedicated for plutonium utilization, could be co-located with facilities for fuel reprocessing ad fuel fabrication to eliminate the off-site transport of separated plutonium. (author)

  15. Fuel cycle oriented approach

    International Nuclear Information System (INIS)

    Petit, A.

    1987-01-01

    The term fuel cycle oriented approach is currently used to designate two quite different things: the attempt to consider all or part of a national fuel cycle as one material balance area (MBA) or to consider individual MBAs existing in a state while designing a unique safeguards approach for each and applying the principle of nondiscrimination to fuel cycles as a whole, rather than to individual facilities. The merits of such an approach are acceptability by the industry and comparison with the contemplated establishment of long-term criteria. The following points concern the acceptability by the industry: (1) The main interest of the industry is to keep an open international market and therefore, to have effective and efficient safeguards. (2) The main concerns of the industry regarding international safeguards are economic burden, intrusiveness, and discrimination. Answers to these legitimate concerns, which retain the benefits of a fuel cycle oriented approach, are needed. More specifically, the problem of reimbursing the operator the costs that he has incurred for the safeguards must be considered

  16. The Geologic Nitrogen Cycle

    Science.gov (United States)

    Johnson, B. W.; Goldblatt, C.

    2013-12-01

    N2 is the dominant gas in Earth's atmosphere, and has been so through the majority of the planet's history. Originally thought to only be cycled in significant amounts through the biosphere, it is becoming increasingly clear that a large degree of geologic cycling can occur as well. N is present in crustal rocks at 10s to 100s of ppm and in the mantle at 1s to perhaps 10s of ppm. In light of new data, we present an Earth-system perspective of the modern N cycle, an updated N budget for the silicate Earth, and venture to explain the evolution of the N cycle over time. In an fashion similar to C, N has a fast, biologically mediated cycle and a slower cycle driven by plate tectonics. Bacteria fix N2 from the atmosphere into bioavailable forms. N is then cycled through the food chain, either by direct consumption of N-fixing bacteria, as NH4+ (the primary waste form), or NO3- (the most common inorganic species in the modern ocean). Some organic material settles as sediment on the ocean floor. In anoxic sediments, NH4+ dominates; due to similar ionic radii, it can readily substitute for K+ in mineral lattices, both in sedimentary rocks and in oceanic lithosphere. Once it enters a subduction zone, N may either be volatilized and returned to the atmosphere at arc volcanoes as N2 or N2O, sequestered into intrusive igneous rocks (as NH4+?), or subducted deep into the mantle, likely as NH4+. Mounting evidence indicates that a significant amount of N may be sequestered into the solid Earth, where it may remain for long periods (100s m.y.) before being returned to the atmosphere/biosphere by volcanism or weathering. The magnitude fluxes into the solid Earth and size of geologic N reservoirs are poorly constrained. The size of the N reservoirs contained in the solid Earth directly affects the evolution of Earth's atmosphere. It is possible that N now sequestered in the solid Earth was once in the atmosphere, which would have resulted in a higher atmospheric pressure, and

  17. The global water cycle

    Science.gov (United States)

    Oki, Taikan; Entekhabi, Dara; Harrold, Timothy Ives

    The global water cycle consists of the oceans, water in the atmosphere, and water in the landscape. The cycle is closed by the fluxes between these reservoirs. Although the amounts of water in the atmosphere and river channels are relatively small, the fluxes are high, and this water plays a critical role in society, which is dependent on water as a renewable resource. On a global scale, the meridional component of river runoff is shown to be about 10% of the corresponding atmospheric and oceanic meridional fluxes. Artificial storages and water withdrawals for irrigation have significant impacts on river runoff and hence on the overall global water cycle. Fully coupled atmosphere-land-river-ocean models of the world's climate are essential to assess the future water resources and scarcities in relation to climate change. An assessment of future water scarcity suggests that water shortages will worsen, with a very significant increase in water stress in Africa. The impact of population growth on water stress is shown to be higher than that of climate change. The virtual water trade, which should be taken into account when discussing the global water cycle and water scarcity, is also considered. The movement of virtual water from North America, Oceania, and Europe to the Middle East, North West Africa, and East Asia represents significant global savings of water. The anticipated world water crisis widens the opportunities for the study of the global water cycle to contribute to the development of sustainability within society and to the solution of practical social problems.

  18. On cycles in the transcription network of Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Berman Piotr

    2008-01-01

    Full Text Available Abstract Background We investigate the cycles in the transcription network of Saccharomyces cerevisiae. Unlike a similar network of Escherichia coli, it contains many cycles. We characterize properties of these cycles and their place in the regulatory mechanism of the cell. Results Almost all cycles in the transcription network of Saccharomyces cerevisiae are contained in a single strongly connected component, which we call LSCC (L for "largest", except for a single cycle of two transcription factors. The fact that LSCC includes almost all cycles is well explained by the properties of a random graph with the same in- and out-degrees of the nodes. Among different physiological conditions, cell cycle has the most significant relationship with LSCC, as the set of 64 transcription interactions that are active in all phases of the cell cycle has overlap of 27 with the interactions of LSCC (of which there are 49. Conversely, if we remove the interactions that are active in all phases of the cell cycle (25% of interactions to transcription factors, the LSCC would have only three nodes and 5 edges, many fewer than expected. This subgraph of the transcription network consists mostly of interactions that are active only in the stress response subnetwork. We also characterize the role of LSCC in the topology of the network. We show that LSCC can be used to define a natural hierarchy in the network and that in every physiological subnetwork LSCC plays a pivotal role. Conclusion Apart from those well-defined conditions, the transcription network of Saccharomyces cerevisiae is devoid of cycles. It was observed that two conditions that were studied and that have no cycles of their own are exogenous: diauxic shift and DNA repair, while cell cycle and sporulation are endogenous. We claim that in a certain sense (slow recovery stress response is endogenous as well.

  19. Planning and management of logistic cycle

    Directory of Open Access Journals (Sweden)

    V. N. Kudashkin

    2017-01-01

    the system – expected results to perform the logistics operations. We can talk about the effectiveness of the functional cycle structure due to the operational needs.The effectiveness of the functional cycle is directly related to the resource cost. The efficiency and productivity of the functional cycles are the key indicators in logistical management.Functional cycles are forming a single supply chain and link its participants. Thus, the functional cycle is the main object of the design and operational management in logistical systems, its structure is the basis for making the integrated logistics.

  20. The Effect of "Rogue" Active Regions on the Solar Cycle

    Science.gov (United States)

    Nagy, Melinda; Lemerle, Alexandre; Labonville, François; Petrovay, Kristóf; Charbonneau, Paul

    2017-11-01

    The origin of cycle-to-cycle variations in solar activity is currently the focus of much interest. It has recently been pointed out that large individual active regions with atypical properties can have a significant impact on the long-term behavior of solar activity. We investigate this possibility in more detail using a recently developed 2×2D dynamo model of the solar magnetic cycle. We find that even a single "rogue" bipolar magnetic region (BMR) in the simulations can have a major effect on the further development of solar activity cycles, boosting or suppressing the amplitude of subsequent cycles. In extreme cases, an individual BMR can completely halt the dynamo, triggering a grand minimum. Rogue BMRs also have the potential to induce significant hemispheric asymmetries in the solar cycle. To study the effect of rogue BMRs in a more systematic manner, a series of dynamo simulations were conducted, in which a large test BMR was manually introduced in the model at various phases of cycles of different amplitudes. BMRs emerging in the rising phase of a cycle can modify the amplitude of the ongoing cycle, while BMRs emerging in later phases will only affect subsequent cycles. In this model, the strongest effect on the subsequent cycle occurs when the rogue BMR emerges around cycle maximum at low latitudes, but the BMR does not need to be strictly cross-equatorial. Active regions emerging as far as 20° from the equator can still have a significant effect. We demonstrate that the combined effect of the magnetic flux, tilt angle, and polarity separation of the BMR on the dynamo is via their contribution to the dipole moment, δ D_{BMR}. Our results indicate that prediction of the amplitude, starting epoch, and duration of a cycle requires an accurate accounting of a broad range of active regions emerging in the previous cycle.

  1. Cycling and erectile dysfunction

    Directory of Open Access Journals (Sweden)

    Ina Šibli

    2015-01-01

    Full Text Available Abstract: For many years medical studies have implicated bicycle riding is causing erectile dysfunction (ED in association with higher perineal pressure. This review focuses upon epidemiological studies assesing the impact of cycling on ED, pathogenesis of ED in cyclists  as well as on research considering changes of perineal pressure, hemodynamics, and nerve conduction when cycling. Investigestors were also interested in different saddle sizes, materials and geometry and also in the impact of saddle and riders position on changes to the perineum. Research on female cyclists is very limited but indicates similar genitourinary disorders as in male cyclists. We also review  research on preventative and therapeutic options regarding bicycle riding and ED.

  2. Fuel cycle services

    International Nuclear Information System (INIS)

    Gruber, Gerhard J.

    1990-01-01

    TRIGA reactor operators are increasingly concerned about the back end of their Fuel Cycle due to a new environmental policy in the USA. The question how to close the Fuel Cycle will have to be answered by all operators sooner or later. Reprocessing of the TRIGA fuel elements is not available. Only long term storage and final disposal can be considered. But for such a storage or disposal a special treatment of the fuel elements and of course a final depository is necessary. NUKEM plans to undertake efforts to assist the TRIGA operators in this area. For that reason we need to know your special needs for today and tomorrow - so that potential processors can consider whether to offer these services on the market. (orig.)

  3. Carbon cycle makeover

    DEFF Research Database (Denmark)

    Canfield, Donald Eugene; Kump, Lee R.

    2013-01-01

    In 1845, the French chemist and mining engineer Jacques-Joseph Ebelman figured out why Earth's atmosphere contains oxygen (1). Oxygen is produced by plants during photosynthesis, but almost all of this oxygen is used again in respiration. Ebelman reasoned that small amounts of organic matter rema...... geochemical cycle. But Earth is an old planet, and oxygen levels have changed through time (2). On page 540 of this issue, Schrag et al. (3) challenge the most commonly used geochemical approach to assess long-term changes in the coupled oxygen and carbon cycles....... remaining in sediments after respiration leave a residual of oxygen in the atmosphere. The source of oxygen to the atmosphere represented by organic matter burial is balanced by oxygen sinks associated with rock weathering and chemical reaction with volcanic gases. This is the long-term carbon and oxygen...

  4. Life Cycle Sustainability Dashboard

    DEFF Research Database (Denmark)

    Traverso, Marzia; Finkbeiner, Matthias; Jørgensen, Andreas

    2012-01-01

    One method to assess the sustainability performance of products is life cycle sustainability assessment (LCSA), which assesses product performance considering the environmental,economic, and social dimensions of the life cycle. The results of LCSA can be used to compare different products...... or to support decision making toward sustainable production and consumption. In both cases, LCSA results could be too disaggregated and consequently too difficult to understand and interpret by decision makers. As non-experts are usually the target audience of experts and scientists, and are also involved...... in decision-making processes, the necessity for a straightforward but comprehensive presentation of LCSA results is becoming strategically important. The implementation of the dashboard of sustainability proposed in this article offers a possible solution. An outstanding characteristic of the dashboard...

  5. Effect of sprint interval versus continuous cycling on postprandial lipaemia.

    Science.gov (United States)

    Tan, Min Sze; Mok, Alexander; Yap, Mei Chan; Burns, Stephen F

    2013-01-01

    The present study compares the effect of a single bout of sprint interval cycling against continuous cycling on postprandial lipaemia. Participants were nine healthy volunteers (five male), aged 20-26 years. Each participant undertook three 2-d trials in a random order. On day 1, participants rested (control), undertook a single 20 minute bout of continuous cycling at 70% of maximum oxygen uptake or completed four 30-second bouts of sprint interval cycling on a cycle ergometer, separated by 4.5 minutes of recovery. On day 2, participants rested and consumed a test meal (75% fat). Triacylglycerol concentrations were measured fasting and for 6 hours after the meal. The total area under the triacylglycerol concentration against time curve was similar among trials (mean (SD): control, 9.51 (3.50) mmol · l(-1) compared with continuous cycling, 8.58 (3.08) mmol · l(-1) compared with sprint interval cycling, 9.28 (1.89) mmol · l(-1); P = 0.517). There was no difference in the pattern of TAG response to the test meal among trials (trial × time interaction, P = 0.637). The present study found no effect of sprint interval or continuous cycling on postprandial lipaemia, with the reason for this finding unclear. Future studies need to more precisely determine the relationship between exercise and postprandial lipaemia across different types of exercise.

  6. Assessing Cycling Participation in Australia

    Directory of Open Access Journals (Sweden)

    Chris Rissel

    2013-01-01

    Full Text Available Planning and evaluating cycling programs at a national or state level requires accurate measures of cycling participation. However, recent reports of cycling participation have produced very different estimates. This paper examines the reported rates of cycling in five recent population surveys of cycling. Three surveys (one national and two from Sydney asking respondents when they last rode a bicycle generated cycling participation (cycled in the past year estimates of 29.7%, 34.1% and 28.9%. Two other national surveys which asked participants to recall (unprompted any physical activity done for exercise, recreation or sport in the previous 12 months, estimated cycling in the past year as 11.1% and 6.5%. While unprompted recall of cycling as a type of physical activity generates lower estimates of cycling participation than specific recall questions, both assessment approaches produced similar patterns of cycling by age and sex with both approaches indicating fewer women and older adults cycling. The different question styles most likely explain the substantial discrepancies between the estimates of cycling participation. Some differences are to be expected due to sampling variability, question differences, and regional variation in cycling.

  7. HCl removal using cycled carbide slag from calcium looping cycles

    International Nuclear Information System (INIS)

    Xie, Xin; Li, Yingjie; Wang, Wenjing; Shi, Lei

    2014-01-01

    Highlights: • Cycled carbide slag from calcium looping cycles is used to remove HCl. • The optimum temperature for HCl removal of cycled carbide slag is 700 °C. • The presence of CO 2 restrains HCl removal of cycled carbide slag. • CO 2 capture conditions have important effects on HCl removal of cycled carbide slag. • HCl removal capacity of carbide slag drops with cycle number rising from 1 to 50. - Abstract: The carbide slag is an industrial waste from chlor-alkali plants, which can be used to capture CO 2 in the calcium looping cycles, i.e. carbonation/calcination cycles. In this work, the cycled carbide slag from the calcium looping cycles for CO 2 capture was proposed to remove HCl in the flue gas from the biomass-fired and RDFs-fired boilers. The effects of chlorination temperature, HCl concentration, particle size, presence of CO 2 , presence of O 2 , cycle number and CO 2 capture conditions in calcium looping cycles on the HCl removal behavior of the carbide slag experienced carbonation/calcination cycles were investigated in a triple fixed-bed reactor. The chlorination product of the cycled carbide slag from the calcium looping after absorbing HCl is not CaCl 2 but CaClOH. The optimum temperature for HCl removal of the cycled carbide slag from the carbonation/calcination cycles is 700 °C. The chlorination conversion of the cycled carbide slag increases with increasing the HCl concentration. The cycled carbide slag with larger particle size exhibits a lower chlorination conversion. The presence of CO 2 decreases the chlorination conversions of the cycled carbide slag and the presence of O 2 has a trifling impact. The chlorination conversion of the carbide slag experienced 1 carbonation/calcination cycle is higher than that of the uncycled calcined sorbent. As the number of carbonation/calcination cycles increases from 1 to 50, the chlorination conversion of carbide slag drops gradually. The high calcination temperature and high CO 2

  8. Stirling cycle engine

    Science.gov (United States)

    Lundholm, Gunnar

    1983-01-01

    In a Stirling cycle engine having a plurality of working gas charges separated by pistons reciprocating in cylinders, the total gas content is minimized and the mean pressure equalization among the serial cylinders is improved by using two piston rings axially spaced at least as much as the piston stroke and by providing a duct in the cylinder wall opening in the space between the two piston rings and leading to a source of minimum or maximum working gas pressure.

  9. Forests and water cycle

    Directory of Open Access Journals (Sweden)

    Iovino F

    2009-06-01

    Full Text Available Based on a comprehensive literature analysis, a review on factors that control water cycle and water use in Mediterranean forest ecosystems is presented, including environmental variables and silvicultural treatments. This important issue is considered in the perspective of sustainable forest management of Mediterranean forests, with special regard to crucial environmental hazards such as forest fires and desertification risks related to climate change.

  10. International Business Cycle

    Directory of Open Access Journals (Sweden)

    Marek Lubiński

    2007-06-01

    Full Text Available Prime stylized facts of international business cycle theory refer to positive correlation in the cyclical components of important macroeconomic variables across countries. However a number of indicators of business cycle synchronization do not point to clear trends. It can be ascribed to the fact that different forces influence level of business cycle correlation. When investigating into the forces behind the commonness in aggregate fluctuations economic research seems to have pointed in two directions. One strand of the literature examines the idea of common exogenous shocks that affect economies simultaneously. In addition to that economic interdependencies such as trade in goods and services or capital account transactions may serve as the channels through which disturbances spill over across countries.The observed degree of output co movement reflects both the nature of the shocks that have occurred and the degree of economic interdependence. In the periods when common shocks prevail level of synchronization is usually higher than in times of transmission dominance.

  11. Terrestrial Carbon Cycle Variability.

    Science.gov (United States)

    Baldocchi, Dennis; Ryu, Youngryel; Keenan, Trevor

    2016-01-01

    A growing literature is reporting on how the terrestrial carbon cycle is experiencing year-to-year variability because of climate anomalies and trends caused by global change. As CO 2 concentration records in the atmosphere exceed 50 years and as satellite records reach over 30 years in length, we are becoming better able to address carbon cycle variability and trends. Here we review how variable the carbon cycle is, how large the trends in its gross and net fluxes are, and how well the signal can be separated from noise. We explore mechanisms that explain year-to-year variability and trends by deconstructing the global carbon budget. The CO 2 concentration record is detecting a significant increase in the seasonal amplitude between 1958 and now. Inferential methods provide a variety of explanations for this result, but a conclusive attribution remains elusive. Scientists have reported that this trend is a consequence of the greening of the biosphere, stronger northern latitude photosynthesis, more photosynthesis by semi-arid ecosystems, agriculture and the green revolution, tropical temperature anomalies, or increased winter respiration. At the global scale, variability in the terrestrial carbon cycle can be due to changes in constituent fluxes, gross primary productivity, plant respiration and heterotrophic (microbial) respiration, and losses due to fire, land use change, soil erosion, or harvesting. It remains controversial whether or not there is a significant trend in global primary productivity (due to rising CO 2 , temperature, nitrogen deposition, changing land use, and preponderance of wet and dry regions). The degree to which year-to-year variability in temperature and precipitation anomalies affect global primary productivity also remains uncertain. For perspective, interannual variability in global gross primary productivity is relatively small (on the order of 2 Pg-C y -1 ) with respect to a large and uncertain background (123 +/- 4 Pg-C y -1 ), and

  12. The Contemporary Carbon Cycle

    Science.gov (United States)

    Houghton, R. A.

    2003-12-01

    The global carbon cycle refers to the exchanges of carbon within and between four major reservoirs: the atmosphere, the oceans, land, and fossil fuels. Carbon may be transferred from one reservoir to another in seconds (e.g., the fixation of atmospheric CO2 into sugar through photosynthesis) or over millennia (e.g., the accumulation of fossil carbon (coal, oil, gas) through deposition and diagenesis of organic matter). This chapter emphasizes the exchanges that are important over years to decades and includes those occurring over the scale of months to a few centuries. The focus will be on the years 1980-2000 but our considerations will broadly include the years ˜1850-2100. Chapter 8.09, deals with longer-term processes that involve rates of carbon exchange that are small on an annual timescale (weathering, vulcanism, sedimentation, and diagenesis).The carbon cycle is important for at least three reasons. First, carbon forms the structure of all life on the planet, making up ˜50% of the dry weight of living things. Second, the cycling of carbon approximates the flows of energy around the Earth, the metabolism of natural, human, and industrial systems. Plants transform radiant energy into chemical energy in the form of sugars, starches, and other forms of organic matter; this energy, whether in living organisms or dead organic matter, supports food chains in natural ecosystems as well as human ecosystems, not the least of which are industrial societies habituated (addicted?) to fossil forms of energy for heating, transportation, and generation of electricity. The increased use of fossil fuels has led to a third reason for interest in the carbon cycle. Carbon, in the form of carbon dioxide (CO2) and methane (CH4), forms two of the most important greenhouse gases. These gases contribute to a natural greenhouse effect that has kept the planet warm enough to evolve and support life (without the greenhouse effect the Earth's average temperature would be -33

  13. How well can business cycle accounting account for business cycles?

    OpenAIRE

    Keisuke Otsu

    2012-01-01

    The business cycle accounting method introduced by Chari, Kehoe and McGrattan (2007) is a useful tool to decompose business cycle fluctuations into their contributing factors. However, the model estimated by the maximum likelihood method cannot replicate business cycle moments computed from data. Moment-based estimation might be an attractive alternative if the purpose of the research is to study business cycle properties such as volatility, persistence and cross-correlation of variables inst...

  14. Bridging the gap between financial reporting and the revenue cycle.

    Science.gov (United States)

    Clark, Kari; Bang, Derek A

    2012-09-01

    Implementing a standardized financial reporting and revenue cycle monitoring platform can help healthcare organizations improve their net revenue reporting and budgeting processes. Consistent, standardized data help the finance office estimate accounts receivable reserves more accurately, streamline the month-end closing process, and strengthen internal controls. The benefits of standardizing the finance and revenue cycle functions are particularly significant in large organizations with multiple facilities, but even single-facility providers can benefit from improved communication between the business office and finance.

  15. Fictitious Supercontinent Cycles

    Science.gov (United States)

    Marvin Herndon, J.

    2014-05-01

    "Supercontinent cycles" or "Wilson cycles" is the idea that before Pangaea there were a series of supercontinents that each formed and then broke apart and separated before colliding again, re-aggregating, and suturing into a new supercontinent in a continuing sequence. I suggest that "supercontinent cycles" are artificial constructs, like planetary orbit epicycles, attempts to describe geological phenomena within the framework of problematic paradigms, namely, planetesimal Earth formation and plate tectonics' mantle convection. The so-called 'standard model of solar system formation' is problematic as it would lead to insufficiently massive planetary cores and necessitates additional ad hoc hypotheses such as the 'frost line' between Mars and Jupiter to explain planetary differences and whole-planet melting to explain core formation from essentially undifferentiated matter. The assumption of mantle convection is crucial for plate tectonics, not only for seafloor spreading, but also for continental movement; continent masses are assumed to ride atop convection cells. In plate tectonics, plate collisions are thought to be the sole mechanism for fold-mountain formation. Indeed, the occurrence of mountain chains characterized by folding which significantly predate the breakup of Pangaea is the primary basis for assuming the existence of supercontinent cycles with their respective periods of ancient mountain-forming plate collisions. Mantle convection is physically impossible. Rayleigh Number justification has been misapplied. The mantle bottom is too dense to float to the surface by thermal expansion. Sometimes attempts are made to obviate the 'bottom heavy' prohibition by adopting the tacit assumption that the mantle behaves as an ideal gas with no viscous losses, i.e., 'adiabatic'. But the mantle is a solid that does not behave as an ideal gas as evidenced by earthquakes occurring at depths as great as 660 km. Absent mantle convection, plate tectonics is not valid

  16. GEOSS Water Cycle Integrator

    Science.gov (United States)

    Koike, Toshio; Lawford, Richard; Cripe, Douglas

    2013-04-01

    It is critically important to recognize and co-manage the fundamental linkages across the water-dependent domains; land use, including deforestation; ecosystem services; and food-, energy- and health-securities. Sharing coordinated, comprehensive and sustained observations and information for sound decision-making is a first step; however, to take full advantage of these opportunities, we need to develop an effective collaboration mechanism for working together across different disciplines, sectors and agencies, and thereby gain a holistic view of the continuity between environmentally sustainable development, climate change adaptation and enhanced resilience. To promote effective multi-sectoral, interdisciplinary collaboration based on coordinated and integrated efforts, the intergovernmental Group on Earth Observations (GEO) is implementing the Global Earth Observation System of Systems (GEOSS). A component of GEOSS now under development is the "GEOSS Water Cycle Integrator (WCI)", which integrates Earth observations, modeling, data and information, management systems and education systems. GEOSS/WCI sets up "work benches" by which partners can share data, information and applications in an interoperable way, exchange knowledge and experiences, deepen mutual understanding and work together effectively to ultimately respond to issues of both mitigation and adaptation. (A work bench is a virtual geographical or phenomenological space where experts and managers collaborate to use information to address a problem within that space). GEOSS/WCI enhances the coordination of efforts to strengthen individual, institutional and infrastructure capacities, especially for effective interdisciplinary coordination and integration. GEO has established the GEOSS Asian Water Cycle Initiative (AWCI) and GEOSS African Water Cycle Coordination Initiative (AfWCCI). Through regional, inter-disciplinary, multi-sectoral integration and inter-agency coordination in Asia and Africa, GEOSS

  17. On the Importance of Cycle Minimum in Sunspot Cycle Prediction

    Science.gov (United States)

    Wilson, Robert M.; Hathaway, David H.; Reichmann, Edwin J.

    1996-01-01

    The characteristics of the minima between sunspot cycles are found to provide important information for predicting the amplitude and timing of the following cycle. For example, the time of the occurrence of sunspot minimum sets the length of the previous cycle, which is correlated by the amplitude-period effect to the amplitude of the next cycle, with cycles of shorter (longer) than average length usually being followed by cycles of larger (smaller) than average size (true for 16 of 21 sunspot cycles). Likewise, the size of the minimum at cycle onset is correlated with the size of the cycle's maximum amplitude, with cycles of larger (smaller) than average size minima usually being associated with larger (smaller) than average size maxima (true for 16 of 22 sunspot cycles). Also, it was found that the size of the previous cycle's minimum and maximum relates to the size of the following cycle's minimum and maximum with an even-odd cycle number dependency. The latter effect suggests that cycle 23 will have a minimum and maximum amplitude probably larger than average in size (in particular, minimum smoothed sunspot number Rm = 12.3 +/- 7.5 and maximum smoothed sunspot number RM = 198.8 +/- 36.5, at the 95-percent level of confidence), further suggesting (by the Waldmeier effect) that it will have a faster than average rise to maximum (fast-rising cycles have ascent durations of about 41 +/- 7 months). Thus, if, as expected, onset for cycle 23 will be December 1996 +/- 3 months, based on smoothed sunspot number, then the length of cycle 22 will be about 123 +/- 3 months, inferring that it is a short-period cycle and that cycle 23 maximum amplitude probably will be larger than average in size (from the amplitude-period effect), having an RM of about 133 +/- 39 (based on the usual +/- 30 percent spread that has been seen between observed and predicted values), with maximum amplitude occurrence likely sometime between July 1999 and October 2000.

  18. Cycle 7 outage experience

    International Nuclear Information System (INIS)

    Gadeken, A.D.

    1986-03-01

    The scheduled 58-day refueling outage in preparation for the seventh operating cycle of the Fast Flux Test Facility (FFTF) was successfully completed three days ahead of schedule. The planning and execution of the outage was greatly aided by Project/2 automated scheduling capabilities. For example, the use of ''maintenance windows'' and resource loading capabilities was particularly effective. The value of the planning process was demonstrated by the smooth transition into the outage phase after an early shutdown and set the stage for our best outage to date

  19. Elementary cycles of time

    Directory of Open Access Journals (Sweden)

    Dolce Donatello

    2013-09-01

    Full Text Available Elementary particles, i.e. the basic constituents of nature, are characterized by quantum recurrences in time. The flow of time of every physical system can be therefore decomposed in elementary cycles of time. This allows us to enforce the local nature of relativistic time, yielding interesting unified descriptions of fundamental aspects of modern physics, as shown in recent publications. Every particle can be regarded as a reference clock with time resolution of the order of the Compton time particle, many orders of magnitude more accurate than the atomic clocks. Here we report basic implications about the resulting notion of time.

  20. The nuclear fuel cycle

    International Nuclear Information System (INIS)

    1998-05-01

    After a short introduction about nuclear power in the world, fission physics and the French nuclear power plants, this brochure describes in a digest way the different steps of the nuclear fuel cycle: uranium prospecting, mining activity, processing of uranium ores and production of uranium concentrates (yellow cake), uranium chemistry (conversion of the yellow cake into uranium hexafluoride), fabrication of nuclear fuels, use of fuels, reprocessing of spent fuels (uranium, plutonium and fission products), recycling of energetic materials, and storage of radioactive wastes. (J.S.)

  1. Nuclear Fuel Cycle Objectives

    International Nuclear Information System (INIS)

    2013-01-01

    . The four Objectives publications include Nuclear General Objectives, Nuclear Power Objectives, Nuclear Fuel Cycle Objectives, and Radioactive Waste management and Decommissioning Objectives. This publication sets out the objectives that need to be achieved in the area of the nuclear fuel cycle to ensure that the Nuclear Energy Basic Principles are satisfied. Within each of these four Objectives publications, the individual topics that make up each area are addressed. The five topics included in this publication are: resources; fuel engineering and performance; spent fuel management and reprocessing; fuel cycles; and the research reactor nuclear fuel cycle

  2. The software life cycle

    CERN Document Server

    Ince, Darrel

    1990-01-01

    The Software Life Cycle deals with the software lifecycle, that is, what exactly happens when software is developed. Topics covered include aspects of software engineering, structured techniques of software development, and software project management. The use of mathematics to design and develop computer systems is also discussed. This book is comprised of 20 chapters divided into four sections and begins with an overview of software engineering and software development, paying particular attention to the birth of software engineering and the introduction of formal methods of software develop

  3. Ocean Thermal Energy Conversion Using Double-Stage Rankine Cycle

    Directory of Open Access Journals (Sweden)

    Yasuyuki Ikegami

    2018-03-01

    Full Text Available Ocean Thermal Energy Conversion (OTEC using non-azeotropic mixtures such as ammonia/water as working fluid and the multistage cycle has been investigated in order to improve the thermal efficiency of the cycle because of small ocean temperature differences. The performance and effectiveness of the multistage cycle are barely understood. In addition, previous evaluation methods of heat exchange process cannot clearly indicate the influence of the thermophysical characteristics of the working fluid on the power output. Consequently, this study investigated the influence of reduction of the irreversible losses in the heat exchange process on the system performance in double-stage Rankine cycle using pure working fluid. Single Rankine, double-stage Rankine and Kalina cycles were analyzed to ascertain the system characteristics. The simple evaluation method of the temperature difference between the working fluid and the seawater is applied to this analysis. From the results of the parametric performance analysis it can be considered that double-stage Rankine cycle using pure working fluid can reduce the irreversible losses in the heat exchange process as with the Kalina cycle using an ammonia/water mixture. Considering the maximum power efficiency obtained in the study, double-stage Rankine and Kalina cycles can improve the power output by reducing the irreversible losses in the cycle.

  4. Sometimes "Newton's Method" Always "Cycles"

    Science.gov (United States)

    Latulippe, Joe; Switkes, Jennifer

    2012-01-01

    Are there functions for which Newton's method cycles for all non-trivial initial guesses? We construct and solve a differential equation whose solution is a real-valued function that two-cycles under Newton iteration. Higher-order cycles of Newton's method iterates are explored in the complex plane using complex powers of "x." We find a class of…

  5. Kondratieff's Long-Wave Cycle.

    Science.gov (United States)

    Volland, Craig S.

    1985-01-01

    The legendary Soviet economist's classic work, "Long-Wave Cycle," has been republished. Admirers believe that it explains how the world's economy works. According to Kondratieff, the world economy follows cycles lasting from 48 to 55 years. His cycle theory is discussed. (Author/RM)

  6. Entrepreneurship and the Business Cycle

    NARCIS (Netherlands)

    Ph.D. Koellinger (Philipp); A.R. Thurik (Roy)

    2011-01-01

    textabstractWe find new empirical regularities in the business cycle in a cross-country panel of 22 OECD countries for the period 1972-2007; entrepreneurship Granger-causes the cycles of the world economy. Furthermore, the entrepreneurial cycle is positively affected by the national unemployment

  7. Kozai Cycles and Tidal Friction

    Energy Technology Data Exchange (ETDEWEB)

    L, K; P.P., E

    2009-07-17

    Several studies in the last three years indicate that close binaries, i.e. those with periods of {approx}< 3 d, are very commonly found to have a third body in attendance. We argue that this proves that the third body is necessary in order to make the inner period so short, and further argue that the only reasonable explanation is that the third body causes shrinkage of the inner period, from perhaps a week or more to the current short period, by means of the combination of Kozai cycles and tidal friction (KCTF). In addition, once KCTF has produced a rather close binary, magnetic braking also combined with tidal friction (MBTF) can decrease the inner orbit further, to the formation of a contact binary or even a merged single star. Some of the products of KCTF that have been suggested, either by others or by us, are W UMa binaries, Blue Stragglers, X-ray active BY Dra stars, and short-period Algols. We also argue that some components of wide binaries are actually merged remnants of former close inner pairs. This may include such objects as rapidly rotating dwarfs (AB Dor, BO Mic) and some (but not all) Be stars.

  8. Nuclear plant life cycle costs

    International Nuclear Information System (INIS)

    Durante, R.W.

    1994-01-01

    Life cycle costs of nuclear power plants in the United States are discussed. The author argues that these costs have been mishandled or neglected. Decommissioning costs have escalated, e.g. from $328 per unit in 1991 to $370 in 1993 for the Sacramento Municipal Utility District, though they still only amount to less than 0.1 cent per kWh. Waste management has been complicated in the U.S. by the decision to abandon civilian reprocessing; by the year 2000, roughly 30 U.S. nuclear power units will have filled their storage pools; dry storage has been delayed, and will be an expense not originally envisaged. Some examples of costs of major component replacement are provided. No single component has caused as much operational disruption and financial penalties as the steam generator. Operation and maintenance costs have increased steadily, and now amount to more than 70% of production costs. A strategic plan by the Nuclear Power Oversight Committee (of U.S. utilities) will ensure that the ability to correctly operate and maintain a nuclear power plant is built into the original design. 6 figs

  9. Nuclear Fuel Cycle; (USA)

    Energy Technology Data Exchange (ETDEWEB)

    Cason, D.L.; Hicks, S.C. (eds.)

    1991-01-01

    Nuclear Fuel Cycle (NFC) announces on a monthly basis the current worldwide information available from the open literature on all aspects of the fuel cycle except in-reactor properties and performance of fuels. More information related to radioactive waste and to the transport and storage of spent fuel is included in the current awareness publication, Radioactive Waste Management. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database (EDB) during the past month. Also included are other US information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency's Technology Data Exchange, the International Atomic Energy Agency's International Nuclear Information System, or government-to-government agreements. The digests in NFC on nuclear fuel back to 1948 are available for online searching and retrieval in EDB and Nuclear Science Abstracts (NSA) database. Current information, added daily to EDB, is available to DOE and its contractors through the DOE Integrated Technical Information System. Customized profiles can be developed to provide current information to meet each user's needs.

  10. The sunspot cycle revisited

    International Nuclear Information System (INIS)

    Lomb, Nick

    2013-01-01

    The set of sunspot numbers observed since the invention of the telescope is one of the most studied time series in astronomy and yet it is also one of the most complex. Fourteen frequencies are found in the yearly mean sunspot numbers from 1700 to 2011using the Lomb-Scargle periodogram and prewhitening. All of the frequencies corresponding to shorter term periods can be matched with simple algebraic combinations of the frequency of the main 11-year period and the frequencies of the longer term periods in the periodogram. This is exactly what can be expected from amplitude and phase modulation of an 11.12-year periodicity by longer term variations. Similar, though not identical, results are obtained after correcting the sunspot number series as proposed by Svalgaard. On looking separately at the amplitude and phase modulation a clear relationship is found between the two modulations although this relationship has broken down for the last four solar cycles. The phase modulation implies that there is a definite underlying period for the solar cycle. Such a clock mechanism does seem to be a possibility in models of the solar dynamo incorporating a conveyor-belt-like meridional circulation between high polar latitudes and the equator.

  11. Fast breeder fuel cycle

    International Nuclear Information System (INIS)

    1978-07-01

    This contribution is prepared for the answer to the questionnaire of working group 5, subgroup B. B.1. is the short review of the fast breeder fuel cycles based on the reference large commercial Japanese LMFBR. The LMFBRs are devided into two types. FBR-A is the reactor to be used before 2000, and its burnup and breeding ratio are relatively low. The reference fuel cycle requirement is calculated based on the FBR-A. FBR-B is the one to be used after 2000, and its burnup and breeding ratio are relatively high. B.2. is basic FBR fuel reprocessing scheme emphasizing the differences with LWR reprocessing. This scheme is based on the conceptual design and research and development work on the small scale LMFBR reprocessing facility of Japan. The facility adopts a conventional PUREX process except head end portions. The report also describes the effects of technical modifications of conventional reprocessing flow sheets, and the problems to be solved before the adoption of these alternatives

  12. Coming Full Cycle.

    Science.gov (United States)

    Fay, Lindsey; Carll-White, Allison; Harrell, James

    2017-04-01

    This article illustrates a collaborative, full cycle diagnostic postoccupancy evaluation (POE) conducted in an emergency department (ED) to demonstrate methods of planning a POE, conducting research to capture meaningful data, and applying outcomes through the use of a design charrette. POEs often end with the reporting of findings rather than suggesting how this knowledge feeds forward. A design charrette presents an opportunity to engage with POE evidence and integrate research into practice. Planning for the POE resulted in a multiphased, multimethodological study. Data collection and analysis utilized objective and subjective measures yielding both qualitative and quantitative data. The design charrette then served as an interactive method to assist design practitioners in both understanding and applying the research findings in the redesign of the entry/triage sequence of the ED. POE findings revealed four key issues impacting the ED experience. These include workflow, communication, privacy and confidentiality, and safety and security. In analyzing the use of the charrette to link POE findings to design application, it was determined that the charrette should include an all-inclusive, collaborative process, easily interpreted evidence, active participant engagement, and feasible outcomes grounded in research. Taking the POE process full cycle is a critical component in bridging the gap between research and its application to design. The charrette process offers a positive mark of completion to the POE and helps participants gain sensitivity to the importance of evidence-based decision-making.

  13. Part 5. Fuel cycle options

    International Nuclear Information System (INIS)

    Lineberry, M.J.; McFarlane, H.F.; Amundson, P.I.; Goin, R.W.; Webster, D.S.

    1980-01-01

    The results of the FBR fuel cycle study that supported US contributions to the INFCE are presented. Fuel cycle technology is reviewed from both generic and historical standpoints. Technology requirements are developed within the framework of three deployment scenarios: the reference international, the secured area, and the integral cycle. Reprocessing, fabrication, waste handling, transportation, and safeguards are discussed for each deployment scenario. Fuel cycle modifications designed to increase proliferation defenses are described and assessed for effectiveness and technology feasibility. The present status of fuel cycle technology is reviewed and key issues that require resolution are identified

  14. Ammonia-water Rankine cycle

    International Nuclear Information System (INIS)

    Bo Hanliang; Ma Changwen; Wu Shaorong

    1997-01-01

    On characteristics of heating source and cooling source in nuclear heating reactor cooperation, the authors advance a new kind of power cycle in which a multicomponent mixture as the work fluid, ammonia-water Rankine cycle, describe its running principle, and compare it with steam Rankine cycle in the same situation. The result is that: the new kind of power cycle, ammonia-water Rankine cycle has higher electricity efficiency; it suits for the situation of heating source and cooling source which offered by nuclear heating reactor cooperation. For low temperature heating source, it maybe has a widely application

  15. Single Particle Studies of Heterogeneous Atmospheric Chemistry on Aluminum Oxide Particles in a Quadrupole Trap

    National Research Council Canada - National Science Library

    Hunter, A

    2000-01-01

    ... on upper atmospheric chemical cycles and ozone. The experimental investigation employs a laboratory quadrupole trap electrodynamic levitation apparatus to study heterogeneous processes on single aluminum oxide particles representative...

  16. Krebs Cycle Wordsearch

    Science.gov (United States)

    Helser, Terry L.

    2001-04-01

    This puzzle embeds 46 names, terms, abbreviations, and acronyms about the citric acid (Krebs) cycle in a 14- x 17-letter matrix. A descriptive narrative beside it describes important features of the pathway. All the terms a student needs to find are embedded there with the first letter followed by underlined blanks to be completed. Therefore, the students usually must find the terms to know how to spell them, correctly fill in the blanks in the narrative with the terms, and then find and highlight the terms in the letter matrix. When all are found, the 24 unused letters complete a sentence that describes a major feature of this central pathway. The puzzle may be used as homework, an extra-credit project, or a group project in the classroom in any course where basic metabolism is learned. It disguises as fun the hard work needed to learn the names of the intermediates, enzymes, and cofactors.

  17. Open cycle thermoacoustics

    Energy Technology Data Exchange (ETDEWEB)

    Reid, Robert Stowers [Georgia Inst. of Technology, Atlanta, GA (United States)

    2000-01-01

    A new type of thermodynamic device combining a thermodynamic cycle with the externally applied steady flow of an open thermodynamic process is discussed and experimentally demonstrated. The gas flowing through this device can be heated or cooled in a series of semi-open cyclic steps. The combination of open and cyclic flows makes possible the elimination of some or all of the heat exchangers (with their associated irreversibility). Heat is directly exchanged with the process fluid as it flows through the device when operating as a refrigerator, producing a staging effect that tends to increase First Law thermodynamic efficiency. An open-flow thermoacoustic refrigerator was built to demonstrate this concept. Several approaches are presented that describe the physical characteristics of this device. Tests have been conducted on this refrigerator with good agreement with a proposed theory.

  18. The planning cycle.

    Science.gov (United States)

    Johnson, William

    2005-01-01

    Information technology planning can be described as a continuous cyclical process composed of three phases whose primary purpose is optimum allocation of scarce resources. In the assessment phase, planners assess user needs, environmental factors, business objectives, and IT infrastructure needs to develop IT projects that address needs in each of these areas. A major goal of this phase is to develop a broad IT inventory. The prioritization phase seeks to ensure optimum allocation of scarce resources by prioritizing ITprojects based on: Costs--total life cycle costs. Benefits--both quantitative and non-quantitative, including support for the organization's strategic business objectives. Risks--subjective assessments of technological and non-technological risks. Implementation requirements--time and personnel requirements to implement the system. The scheduling phase incorporates sequencing considerations, personnel availability, and budgetary constraints to produce an IT plan in which project priorities are adjusted to meet organizational realities.

  19. The nuclear fuel cycle

    International Nuclear Information System (INIS)

    Vernaz, Etienne

    2015-10-01

    The author proposes an overview of the different steps of the nuclear fuel cycle: uranium mining (applied processes, formation of Yellow Cake), conversion into uranium hexafluoride (UF 6 ) for enrichment purposes, enrichment (physical methods and plants), nuclear fuel fabrication (description of a fuel assembly), physical, chemical and radiological evolution of the nuclear fuel in the reactor, spent fuel warehousing, spent fuel processing (dissolution, methods of liquid/liquid extraction, output products), effluents and by-products, recycling of valuable materials (URE, MOX, RNR and others), waste containment for the different waste types regarding their radioactivity level and lifetime (vitrification, shell compacting, cementation, and other processes). The author also presents the French policy and choices regarding spent fuel processing and waste management

  20. The Pyrogenic Carbon Cycle

    Science.gov (United States)

    Bird, Michael I.; Wynn, Jonathan G.; Saiz, Gustavo; Wurster, Christopher M.; McBeath, Anna

    2015-05-01

    Pyrogenic carbon (PyC; includes soot, char, black carbon, and biochar) is produced by the incomplete combustion of organic matter accompanying biomass burning and fossil fuel consumption. PyC is pervasive in the environment, distributed throughout the atmosphere as well as soils, sediments, and water in both the marine and terrestrial environment. The physicochemical characteristics of PyC are complex and highly variable, dependent on the organic precursor and the conditions of formation. A component of PyC is highly recalcitrant and persists in the environment for millennia. However, it is now clear that a significant proportion of PyC undergoes transformation, translocation, and remineralization by a range of biotic and abiotic processes on comparatively short timescales. Here we synthesize current knowledge of the production, stocks, and fluxes of PyC as well as the physical and chemical processes through which it interacts as a dynamic component of the global carbon cycle.

  1. Variable cycle engine

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, A.P.; Sprunger, E.V.

    1980-09-16

    A variable cycle turboshaft engine includes a remote fan system and respective high and low pressure systems for selectively driving the fan system in such a manner as to provide VTOL takeoff capability and minimum specific fuel consumption (SFC) at cruise and loiter conditions. For takeoff the fan system is primarily driven by the relatively large low pressure system whose combustor receives the motive fluid from a core bypass duct and, for cruise and loiter conditions, the fan system is driven by both a relatively small high pressure core and the low pressure system with its combustor inoperative. A mixer is disposed downstream of the high pressure system for mixing the relatively cold air from the bypass duct and the relatively hot air from the core prior to its flow to the low pressure turbine.

  2. HTGR fuel cycle

    International Nuclear Information System (INIS)

    1987-08-01

    In the spring of 1987, the HTGR fuel cycle project has been existing for ten years, and for this reason a status seminar has been held on May 12, 1987 in the Juelich Nuclear Research Center, that gathered the participants in this project for a discussion on the state of the art in HTGR fuel element development, graphite development, and waste management. The papers present an overview of work performed so far and an outlook on future tasks and goals, and on taking stock one can say that the project has been very successful so far: The HTGR fuel element now available meets highest requirements and forms the basis of today's HTGR safety philosophy; research work on graphite behaviour in a high-temperature reactor has led to complete knowledge of the temperature or neutron-induced effects, and with the concept of direct ultimate waste disposal, the waste management problem has found a feasible solution. (orig./GL) [de

  3. Life Cycle Inventory Analysis

    DEFF Research Database (Denmark)

    Bjørn, Anders; Moltesen, Andreas; Laurent, Alexis

    2017-01-01

    The inventory analysis is the third and often most time-consuming part of an LCA. The analysis is guided by the goal and scope definition, and its core activity is the collection and compilation of data on elementary flows from all processes in the studied product system(s) drawing on a combination...... of different sources. The output is a compiled inventory of elementary flows that is used as basis of the subsequent life cycle impact assessment phase. This chapter teaches how to carry out this task through six steps: (1) identifying processes for the LCI model of the product system; (2) planning...... and collecting data; (3) constructing and quality checking unit processes; (4) constructing LCI model and calculating LCI results; (5) preparing the basis for uncertainty management and sensitivity analysis; and (6) reporting....

  4. Analysis of Cell Cycle Dynamics using Probabilistic Cell Cycle Models

    Science.gov (United States)

    Gurkan-Cavusoglu, Evren; Schupp, Jane E.; Kinsella, Timothy J.; Loparo, Kenneth A.

    2013-01-01

    In this study, we develop asynchronous probabilistic cell cycle models to quantitatively assess the effect of ionizing radiation on a human colon cancer cell line. We use both synchronous and asynchronous cell populations and follow treated cells for up to 2 cell cycle times. The model outputs quantify the changes in cell cycle dynamics following ionizing radiation treatment, principally in the duration of both G1 and G2/M phases. PMID:22254270

  5. The Hamburg oceanic carbon cycle circulation model. Cycle 1

    International Nuclear Information System (INIS)

    Maier-Reimer, E.; Heinze, C.

    1992-02-01

    The carbon cycle model calculates the prognostic fields of oceanic geochemical carbon cycle tracers making use of a 'frozen' velocity field provided by a run of the LSG oceanic circulation model (see the corresponding manual, LSG=Large Scale Geostrophic). The carbon cycle model includes a crude approximation of interactions between sediment and bottom layer water. A simple (meridionally diffusive) one layer atmosphere model allows to calculate the CO 2 airborne fraction resulting from the oceanic biogeochemical interactions. (orig.)

  6. Automated Single Cell Data Decontamination Pipeline

    Energy Technology Data Exchange (ETDEWEB)

    Tennessen, Kristin [Lawrence Berkeley National Lab. (LBNL), Walnut Creek, CA (United States). Dept. of Energy Joint Genome Inst.; Pati, Amrita [Lawrence Berkeley National Lab. (LBNL), Walnut Creek, CA (United States). Dept. of Energy Joint Genome Inst.

    2014-03-21

    Recent technological advancements in single-cell genomics have encouraged the classification and functional assessment of microorganisms from a wide span of the biospheres phylogeny.1,2 Environmental processes of interest to the DOE, such as bioremediation and carbon cycling, can be elucidated through the genomic lens of these unculturable microbes. However, contamination can occur at various stages of the single-cell sequencing process. Contaminated data can lead to wasted time and effort on meaningless analyses, inaccurate or erroneous conclusions, and pollution of public databases. A fully automated decontamination tool is necessary to prevent these instances and increase the throughput of the single-cell sequencing process

  7. Menstrual cycle pattern and fertility

    DEFF Research Database (Denmark)

    Kolstad, Henrik A.; Bonde, Jens Peter; Hjøllund, Niels Henrik

    1999-01-01

    OBJECTIVE: To characterize how the menstrual cycle pattern relates to fertility regardless of potential biases caused by inappropriate coital timing during the menstrual cycle or early embryonal loss. DESIGN: Prospective follow-up study. SETTING: Healthy couples recruited throughout Denmark....... PATIENT(S): Two hundred ninety-five couples who were planning their first pregnancy were followed up from the discontinuation of birth control until a pregnancy was recognized within six menstrual cycles. Early embryonal losses were detected by changes in urinary hCG levels. INTERVENTION(S): None. MAIN...... OUTCOME MEASURE(S): The probability of pregnancy occurring within one menstrual cycle (fecundity). RESULT(S): In women who had a cycle length that differed by >10 days from the usual cycle length, fecundity was approximately 25% that of women who had no variation (odds ratio 0.25, 95% confidence interval...

  8. Removing Cycles in Esterel Programs

    Directory of Open Access Journals (Sweden)

    Reinhard von Hanxleden

    2007-05-01

    Full Text Available Esterel belongs to the family of synchronous programming languages, which are affected by cyclic signal dependencies. This prohibits a static scheduling, limiting the choice of available compilation techniques for programs with such cycles. This work proposes an algorithm that, given a constructive synchronous Esterel program, performs a semantics-preserving source code level transformation that removes cyclic signal dependencies. The transformation is divided into two parts: detection of cycles and iterative resolution of these cycles. It is based on the replacement of cycle signals by a signal expression involving no other cycle signals, thereby breaking the cycle. This transformation of cyclic Esterel programs enables the use of efficient compilation techniques, which are only available for acyclic programs. Furthermore, experiments indicate that the code transformation can even improve code quality produced by compilers that can already handle cyclic programs.

  9. The Global Nitrogen Cycle

    Science.gov (United States)

    Galloway, J. N.

    2003-12-01

    Once upon a time nitrogen did not exist. Today it does. In the intervening time the universe was formed, nitrogen was created, the Earth came into existence, and its atmosphere and oceans were formed! In this analysis of the Earth's nitrogen cycle, I start with an overview of these important events relative to nitrogen and then move on to the more traditional analysis of the nitrogen cycle itself and the role of humans in its alteration.The universe is ˜15 Gyr old. Even after its formation, there was still a period when nitrogen did not exist. It took ˜300 thousand years after the big bang for the Universe to cool enough to create atoms; hydrogen and helium formed first. Nitrogen was formed in the stars through the process of nucleosynthesis. When a star's helium mass becomes great enough to reach the necessary pressure and temperature, helium begins to fuse into still heavier elements, including nitrogen.Approximately 10 Gyr elapsed before Earth was formed (˜4.5 Ga (billion years ago)) by the accumulation of pre-assembled materials in a multistage process. Assuming that N2 was the predominate nitrogen species in these materials and given that the temperature of space is -270 °C, N2 was probably a solid when the Earth was formed since its boiling point (b.p.) and melting point (m.p.) are -196 °C and -210 °C, respectively. Towards the end of the accumulation period, temperatures were probably high enough for significant melting of some of the accumulated material. The volcanic gases emitted by the resulting volcanism strongly influenced the surface environment. Nitrogen was converted from a solid to a gas and emitted as N2. Carbon and sulfur were probably emitted as CO and H2S (Holland, 1984). N2 is still the most common nitrogen volcanic gas emitted today at a rate of ˜2 TgN yr-1 (Jaffee, 1992).Once emitted, the gases either remained in the atmosphere or were deposited to the Earth's surface, thus continuing the process of biogeochemical cycling. The rate of

  10. Phloem-specific expression of Yang cycle genes and identification of novel Yang cycle enzymes in Plantago and Arabidopsis.

    Science.gov (United States)

    Pommerrenig, Benjamin; Feussner, Kirstin; Zierer, Wolfgang; Rabinovych, Valentyna; Klebl, Franz; Feussner, Ivo; Sauer, Norbert

    2011-05-01

    The 5-methylthioadenosine (MTA) or Yang cycle is a set of reactions that recycle MTA to Met. In plants, MTA is a byproduct of polyamine, ethylene, and nicotianamine biosynthesis. Vascular transcriptome analyses revealed phloem-specific expression of the Yang cycle gene 5-METHYLTHIORIBOSE KINASE1 (MTK1) in Plantago major and Arabidopsis thaliana. As Arabidopsis has only a single MTK gene, we hypothesized that the expression of other Yang cycle genes might also be vascular specific. Reporter gene studies and quantitative analyses of mRNA levels for all Yang cycle genes confirmed this hypothesis for Arabidopsis and Plantago. This includes the Yang cycle genes 5-METHYLTHIORIBOSE-1-PHOSPHATE ISOMERASE1 and DEHYDRATASE-ENOLASE-PHOSPHATASE-COMPLEX1. We show that these two enzymes are sufficient for the conversion of methylthioribose-1-phosphate to 1,2-dihydroxy-3-keto-5-methylthiopentene. In bacteria, fungi, and animals, the same conversion is catalyzed in three to four separate enzymatic steps. Furthermore, comparative analyses of vascular and nonvascular metabolites identified Met, S-adenosyl Met, and MTA preferentially or almost exclusively in the vascular tissue. Our data represent a comprehensive characterization of the Yang cycle in higher plants and demonstrate that the Yang cycle works primarily in the vasculature. Finally, expression analyses of polyamine biosynthetic genes suggest that the Yang cycle in leaves recycles MTA derived primarily from polyamine biosynthesis.

  11. Entrepreneurship and the business cycle

    OpenAIRE

    Roy Thurik

    2014-01-01

    Entrepreneurship has a cyclical component, raising two questions. Is the entrepreneurship cycle related to the business cycle? And is there causality? A two-way relationship between entrepreneurship and the business cycle would be in line with the two faces of entrepreneurs: as agents of change creating upswings (opportunity entrepreneurship) and as rational actors escaping unemployment by setting up a business (necessity entrepreneurship). Nascent entrepreneurship can indeed be precyclical, ...

  12. Hamiltonian cycles in polyhedral maps

    Indian Academy of Sciences (India)

    Dipendu Maity

    2017-08-24

    Aug 24, 2017 ... Let v be a vertex of K. The link of v is a cycle, say C1(v1, ..., vr ). Since the cycle C is Hamiltonian cycle in EG(K), so, it contains all the vertices of K ..... spanning tree in G . If it does not contain spanning tree then search its forest. By Kruskal's algorithm, it takes O((m − n)log(m − n)) times. If G is connected i.e. ...

  13. Soleus stretch reflex during cycling

    DEFF Research Database (Denmark)

    Grey, Michael James; Pierce, C. W.; Milner, T. E.

    2001-01-01

    the crank cycle, producing ankle dorsiflexion perturbations of similar trajectory. The stretch reflex was greatest during the power phase of the crank cycle and was decreased to the level of background EMG during recovery. Matched perturbations were induced under static conditions at the same crank angle...... active cycling as has been shown with the H-reflex. This lack of depression may reflect a decreased susceptibility of the stretch reflex to inhibition, possibly originating from presynaptic mechanisms....

  14. Interception of FH spread-spectrum signals: Performance advantages of cycle detectors

    Science.gov (United States)

    Fresa, Antonio; Izzo, Luciano; Paura, Luigi

    The interception of weak frequency-hopped (FH) spread-spectrum signals corrupted by broadband noise with unknown and changing power spectral density level is discussed. The doubly stochastic processes are considered to model the noise level as a random variable. The deflection is utilized to compare the performances of the conventional radiometer and the recently proposed single-cycle detector. The results confirm that, for long collect times, the single-cycle detector can outperform the radiometer for relatively small uncertainty in the noise level. Moreover, the Conditions are thus established for the bit rate and the carrier frequency separation to assure a significant superiority of the single-cycle detector.

  15. Analysis of an integrated solar combined cycle with steam and organic Rankine cycles as bottoming cycles

    International Nuclear Information System (INIS)

    Shaaban, S.

    2016-01-01

    Highlights: • A novel ISCC with steam and organic Rankine cycles ORC as bottoming cycles was introduced. • The operating conditions of the cycle were optimized using the genetic optimization algorithm. • R1234ze(z) was found to be the best working fluid for the bottoming ORC. • The output power was improved by 19.5% with solar contribution and 23.1% without solar contribution. • The proposed cycle is less affected by variations of the ambient temperature. - Abstract: Integrated Solar Combined Cycles (ISCC) are currently used in countries with high incident solar radiation in order to increase the net output power and decrease the specific fuel consumption. The present work introduces a modified ISCC with two bottoming cycles. The first bottoming cycle is a steam Rankine cycle while the second one is an Organic Rankine Cycle ORC. Multistage compression with intercooling was considered for the gas turbine unit. The ORC was used in order to intercool the compressed air and produce a net power from the received thermal energy. The proposed cycle performance was studied and optimized. Fifteen working fluids were investigated for use with the ORC. Results showed that R1234ze(z) introduces a good compromise between thermodynamics, economic, safety and environmental considerations. The cycle with R1234ze(z) as a working fluid showed an increase of the output power by 19.5% with solar contribution and 23.1% without solar contribution. The increase of the net output power with the application of the proposed cycle is higher than the power produced from a 50 MW solar field. Moreover, the proposed cycle is less affected by variations of the ambient temperature.

  16. Regenerative superheated steam turbine cycles

    Science.gov (United States)

    Fuller, L. C.; Stovall, T. K.

    1980-01-01

    PRESTO computer program was developed to analyze performance of wide range of steam turbine cycles with special attention given to regenerative superheated steam turbine cycles. It can be used to model standard turbine cycles, including such features as process steam extraction, induction and feedwater heating by external sources, peaking, and high back pressure. Expansion line efficiencies, exhaust loss, leakages, mechanical losses, and generator losses are used to calculate cycle heat rate and generator output. Program provides power engineer with flexible aid for design and analysis of steam turbine systems.

  17. The nitrogen cycle.

    Science.gov (United States)

    Stein, Lisa Y; Klotz, Martin G

    2016-02-08

    Nitrogen is the fourth most abundant element in cellular biomass, and it comprises the majority of Earth's atmosphere. The interchange between inert dinitrogen gas (N2) in the extant atmosphere and 'reactive nitrogen' (those nitrogen compounds that support, or are products of, cellular metabolism and growth) is entirely controlled by microbial activities. This was not the case, however, in the primordial atmosphere, when abiotic reactions likely played a significant role in the inter-transformation of nitrogen oxides. Although such abiotic reactions are still important, the extant nitrogen cycle is driven by reductive fixation of dinitrogen and an enzyme inventory that facilitates dinitrogen-producing reactions. Prior to the advent of the Haber-Bosch process (the industrial fixation of N2 into ammonia, NH3) in 1909, nearly all of the reactive nitrogen in the biosphere was generated and recycled by microorganisms. Although the Haber-Bosch process more than quadrupled the productivity of agricultural crops, chemical fertilizers and other anthropogenic sources of fixed nitrogen now far exceed natural contributions, leading to unprecedented environmental degradation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. The earth's hydrological cycle

    CERN Document Server

    Bonnet, R-M; Calisto, M; Destouni, G; Gurney, R; Johannessen, J; Kerr, Y; Lahoz, WA; Rast, M

    2014-01-01

    This book gives a comprehensive presentation of our present understanding of the Earth's Hydrological cycle and the problems, consequences and impacts that go with this topic. Water is a central component in the Earth's system. It is indispensable for life on Earth in its present form and influences virtually every aspect of our planet's life support system. On relatively short time scales, atmospheric water vapor interacts with the atmospheric circulation and is crucial in forming the Earth's climate zones. Water vapor is the most powerful of the greenhouse gases and serves to enhance the tropospheric temperature. The dominant part of available water on Earth resides in the oceans. Parts are locked up in the land ice on Greenland and Antarctica and a smaller part is estimated to exist as groundwater. If all the ice over the land and all the glaciers were to melt, the sea level would rise by some 80 m. In comparison, the total amount of water vapor in the atmosphere is small; it amounts to ~ 25 kg/m2, or the ...

  19. Life-cycle management

    International Nuclear Information System (INIS)

    Economic factors have contributed to the decision to close Yankee Rowe, San Onofre Unit 1, and Trojan nuclear plants. As nuclear plants age, uncertainties related to major component and system replacement can affect their capital cost contribution to the price of electricity. These costs, their timing, and associated uncertainties can be prohibitive if the remaining plant life is too short. However, these costs may be acceptable if plant service life is extended. Life-cycle management (LCM) is a method of evaluating those options which ultimately affect the useful life of a power plant. This paper presents the methods and an example of an LCM evaluation of a Salt Water Service Water System. Cost-benefit analyses were developed by quantifying age-related degradation mechanisms for various lining and replacement materials, determining their probabilistic life distributions, and developing service repair/replacement alternatives. For each alternative, the maintenance requirements and life expectancy and their associated costs were determined. The probabilistic approach and sensitivity analyses demonstrated the confidence in and the economic value of each alternative. To determine the effect of license renewal and to fully appreciate the value of the repair/replacement alternatives, the PVRR costs were determined with and without a 20-year license renewal. The use of this method also allowed the identification of technical and cost parameters critical to the decision making process

  20. Biomass Gasification Combined Cycle

    Energy Technology Data Exchange (ETDEWEB)

    Judith A. Kieffer

    2000-07-01

    Gasification combined cycle continues to represent an important defining technology area for the forest products industry. The ''Forest Products Gasification Initiative'', organized under the Industry's Agenda 2020 technology vision and supported by the DOE ''Industries of the Future'' program, is well positioned to guide these technologies to commercial success within a five-to ten-year timeframe given supportive federal budgets and public policy. Commercial success will result in significant environmental and renewable energy goals that are shared by the Industry and the Nation. The Battelle/FERCO LIVG technology, which is the technology of choice for the application reported here, remains of high interest due to characteristics that make it well suited for integration with the infrastructure of a pulp production facility. The capital cost, operating economics and long-term demonstration of this technology area key input to future economically sustainable projects and must be verified by the 200 BDT/day demonstration facility currently operating in Burlington, Vermont. The New Bern application that was the initial objective of this project is not currently economically viable and will not be implemented at this time due to several changes at and around the mill which have occurred since the inception of the project in 1995. The analysis shows that for this technology, and likely other gasification technologies as well, the first few installations will require unique circumstances, or supportive public policies, or both to attract host sites and investors.

  1. Uso de antagonista de GnRH (cetrorelix em dose única para evitar ovulações prematuras em ciclos de fertilização assistida Single dose of GnRH antagonist (cetrorelix to avoid premature ovulation in assisted fertilization cycles

    Directory of Open Access Journals (Sweden)

    Pedro Luís Rosan

    2003-09-01

    gravidez foram semelhantes entre os dois grupos. Estudos prospectivos com maior número de pacientes são necessários para confirmar estes achados.PURPOSE: to verify the efficacy of a single subcutaneous dose of cetrorelix acetate to avoid premature ovulation in assisted fertilization cycles. METHODS: this is a prospective, controlled and randomized study, with 20 women undergoing ovarian stimulation for assisted fertilization, 10 of whom were submitted to classical GnRH agonist protocol (control group while 10 utilized a 3-mg subcutaneous dose of the GnRH antagonist on the 7th day of ovarian stimulation (cetrorelix group. Serum FSH, LH, estradiol and progesterone concentrations were assessed on the first, seventh, HCG administration and oocyte retrieval days. Both groups were compared for pituitary suppression (progesterone concentration on HCG day and assisted fertilization cycle performance (gonadotropin ampoules utilized, follicles over 18 mm, retrieved oocytes, fertilization, implantation and pregnancy rates, utilizing Mann-Whitney and Fisher exact tests. RESULTS: no significant difference was observed between control and cetrorelix groups, respectively, for medians of age (31.5 and 34 years, body mass index (24 and 22, gonadotropin ampoles utilized (34 and 32, follicles over 18 mm (3.5 and 3.3, retrieved oocytes (11 and 5, obtained embryos (4 and 3, fertilization (93,7 and 60%, p=0.07 and pregnancy rates (50 and 60%, p=0.07. Efficient pituitary blockade through the ovarian stimulation period was observed for both groups. CONCLUSIONS: these results confirm the efficacy of a 3-mg dose of cetrorelix acetate to prevent premature ovulation in patients undergoing assisted fertilization and suggest a tendency towards a smaller number of embryos and fertilization rates in the cetrorelix group than in the control group. Implantation and pregnancy rates were similar between groups. Other prospective studies with a greater number of patients should be performed to confirm

  2. 'Benefits cycle' replacing premium cycle as consumerism takes hold.

    Science.gov (United States)

    2002-05-01

    The traditional premium cycle of ups and downs in rates is giving way to a new phenomenon--driven by the advent of consumerism in health care--termed the "benefits cycle" by one consultant. Rather than shifts in rates, he argues, the future will see shifts in benefits packages.

  3. Effect of a weight cycle on visceral fat accumulation

    NARCIS (Netherlands)

    van der Kooy, K; Leenen, R; Seidell, J C; Deurenberg, P.; Hautvast, J.G.A.J.

    1993-01-01

    Magnetic resonance imaging was used to study the effect of a single weight cycle on three fat depots: the visceral and subcutaneous abdominal depots and the subcutaneous depot at the trochanter level. Obese subjects (17 men, 15 women) were examined before and after weight-loss intervention and 67 wk

  4. A 9 K conical Stirling-cycle cryocooler

    International Nuclear Information System (INIS)

    Myrtle, K.; Winter, C.; Gygax, S.

    1982-01-01

    A low power closed cycle Stirling refrigerator with a conical glass-fibre reinforced epoxy displacer/regenerator and an external compressor is described. The single stage device has demonstrated cooling to 9 K directly from room temperature and may be used for cooling SQUID systems. (author)

  5. Analysis of Decentralized Control for Absorption Cycle Heat Pumps

    DEFF Research Database (Denmark)

    Vinther, Kasper; Just Nielsen, Rene; Nielsen, Kirsten Mølgaard

    2015-01-01

    Email Print Request Permissions This paper investigates decentralized control structures for absorption cycle heat pumps and a dynamic nonlinear model of a single-effect LiBr-water absorption system is used as case study. The model has four controllable inputs, which can be used to stabilize...

  6. Capabilities For Modelling Of Conversion Processes In Life Cycle Assessment

    DEFF Research Database (Denmark)

    Damgaard, Anders; Zarrin, Bahram; Tonini, Davide

    Life cycle assessment was traditionally used for modelling of product design and optimization. This is also seen in the conventional LCA software which is optimized for the modelling of single materials streams of a homogeneous nature that is assembled into a final product. There has therefore been...

  7. Hamiltonian Cycles on a Random Three-coordinate Lattice

    DEFF Research Database (Denmark)

    Eynard, B.; Guitter, E.; Kristjansen, C.

    1998-01-01

    Consider a random three-coordinate lattice of spherical topology having 2v vertices and being densely covered by a single closed, self-avoiding walk, i.e. being equipped with a Hamiltonian cycle. We determine the number of such objects as a function of v. Furthermore we express the partition...

  8. Uncertainty in Life Cycle Assessment of Nanomaterials

    Science.gov (United States)

    Seager, T. P.; Linkov, I.

    Despite concerns regarding environmental fate and toxicology, engineered nanostructured material manufacturing is expanding at an increasingly rapid pace. In particular, the unique properties of single walled carbon nanotubes (SWCNT) have made them attractive in many areas, including high-tech power applications such as experimental batteries, fuel cells or electrical wiring. The intensity of research interest in SWCNT has raised questions regarding the life cycle environmental impact of nanotechnologies, including assessment of: worker and consumer safety, greenhouse gas emissions, toxicological risks associated with production or product emissions and the disposition of nanoproducts at end of life. However, development of appropriate nanotechnology assessment tools has lagged progress in the nanotechnologies themselves. In particular, current approaches to life cycle assessment (LCA) — originally developed for application in mature manufacturing industries such as automobiles and chemicals — suffer from several shortcomings that make applicability to nanotechnologies problematic. Among these are uncertainties related to the variability of material properties, toxicity and risk, technology performance in the use phase, nanomaterial degradation and change during the product life cycle and the impact assessment stage of LCA. This chapter expounds upon the unique challenges presented by nanomaterials in general, specifies sources of uncertainty and variability in LCA of SWCNT for use in electric and hybrid vehicle batteries and makes recommendations for modeling and decision-making using LCA in a multi-criteria decision analysis framework under conditions of high uncertainty.1

  9. The sweet side of the cell cycle.

    Science.gov (United States)

    Tan, Ee Phie; Duncan, Francesca E; Slawson, Chad

    2017-04-15

    Cell division (mitosis) and gamete production (meiosis) are fundamental requirements for normal organismal development. The mammalian cell cycle is tightly regulated by different checkpoints ensuring complete and precise chromosomal segregation and duplication. In recent years, researchers have become increasingly interested in understanding how O -GlcNAc regulates the cell cycle. The O -GlcNAc post-translation modification is an O -glycosidic bond of a single β- N -acetylglucosamine sugar to serine/threonine residues of intracellular proteins. This modification is sensitive toward changes in nutrient levels in the cellular environment making O -GlcNAc a nutrient sensor capable of influencing cell growth and proliferation. Numerous studies have established that O-GlcNAcylation is essential in regulating mitosis and meiosis, while loss of O-GlcNAcylation is lethal in growing cells. Moreover, aberrant O-GlcNAcylation is linked with cancer and chromosomal segregation errors. In this review, we will discuss how O -GlcNAc controls different aspects of the cell cycle with a particular emphasis on mitosis and meiosis. © 2017 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

  10. Weight and power optimization of steam bottoming cycle for offshore oil and gas installations

    OpenAIRE

    Nord, Lars O.; Martelli, Emanuele; Bolland, Olav

    2014-01-01

    Offshore oil and gas installations are mostly powered by simple cycle gas turbines. To increase the efficiency, a steam bottoming cycle could be added to the gas turbine. One of the keys to the implementation of combined cycles on offshore oil and gas installations is for the steam cycle to have a low weight-to-power ratio. In this work, a detailed combined cycle model and numerical optimization tools were used to develop designs with minimum weight-to-power ratio. Within the work, single-obj...

  11. Project for rationalization measures for international energy conservation. Model project concerning efficient consumption of energy for international energy conservation (Model project of waste heat recovery on billet reheating furnace); 1999 nendo kokusai energy shiyo gorika nado taisaku jigyo seika hokokusho. Kokusai energy shohi koritsuka nado model jigyo (kozai kanetsuro hainetsu kaishu model jigyo)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-03-01

    For the purpose of curtailing energy consumption in the steel industry, a heavy energy consuming industry in Thailand, a model project was carried out for waste heat recovery on a billet reheating furnace, with the fiscal 1999 results compiled. This model project is to install a high efficiency recuperator and the latest combustion control system in the existing furnace in a SISCO (The Siam Iron and Steel Co., Ltd.) plant in Thailand. This year, following the preceding year, the construction manual was prepared, as were the test run manual, performance verification manual, operation and maintenance manual, etc. Supervisors were also dispatched to the site, giving guidance of the installation work, test run and the demonstrative operation, on the basis of these documents. Operation for verifying performance of the equipment was implemented on November 17, 1999, with the intended results obtained. Subsequently, operation maintenance instructors were dispatched, with energy saving effect proved through the collection/analysis of operation data and monitoring, for example. Further, as the dissemination activities, pamphlets and videos were prepared, and seminars were held, among others. (NEDO)

  12. Oxy-fuel technology - Rebox flameless - for reheating and annealing furnaces to increase capacity and reduce operation costs - industrial results; Tecnologia oxi-combustivel - Rebox 'flameless' - em fornos de reaqucimento e recozimento par aumento da capacidade produtiva e reducao dos custos energeticos - resultados industriais

    Energy Technology Data Exchange (ETDEWEB)

    Kfouri, Carlos Eduardo [The Linde Group, Munich (Germany). Iron Foundry and Steel; Nunes, Paulo Rogerio [The Linde Group, Munich (Germany). Metalurgia; Lugnet, Anders [The Linde Group, Munich (Germany). Steel Application Development; Scheele, Joachim von [The Linde Group, Munich (Germany). Metals and Glass Industries

    2010-07-01

    Most steel producers need solutions for higher production throughput in their reheat and annealing furnaces. The goals are to sell more and to improve utilization of investments in existing rolling mills and annealing operations, but also to facilitate the possible restructuring of business and to better manage peak volume demand. Additional throughput capacity also allows for repair and maintenance activities. Removing the nitrogen ballast from the combustion and heat transfer process improves furnace operation drastically. It has in over 120 all Rebox oxy fuel installations been reported that if replacing the combustion air with industrial grade oxygen, that furnace throughput can be boosted by up to 50%, and fossil fuel consumption cut by 50%. It facilitates the use of low-grade fuels since the necessary high flame temperatures can be achieved. Rebox is compact and powerful for a cost-effective retrofit in an existing or new furnace. It complies with ever-stricter requirements for emissions of CO{sub 2} and NO{sub x}. (author)

  13. Evolution of high duty cycle echolocation in bats

    DEFF Research Database (Denmark)

    Fenton, M. B.; Faure, P. A.; Ratcliffe, J. M.

    2012-01-01

    Duty cycle describes the relative 'on time' of a periodic signal. In bats, we argue that high duty cycle (HDC) echolocation was selected for and evolved from low duty cycle (LDC) echolocation because increasing call duty cycle enhanced the ability of echolocating bats to detect, lock onto and track...... fluttering insects. Most echolocators (most bats and all birds and odontocete cetaceans) use LDC echolocation, separating pulse and echo in time to avoid forward masking. They emit short duration, broadband, downward frequency modulated (FM) signals separated by relatively long periods of silence....... In contrast, bats using HDC echolocation emit long duration, narrowband calls dominated by a single constant frequency (CF) separated by relatively short periods of silence. HDC bats separate pulse and echo in frequency by exploiting information contained in Doppler-shifted echoes arising from their movements...

  14. Brucella abortus Cell Cycle and Infection Are Coordinated.

    Science.gov (United States)

    De Bolle, Xavier; Crosson, Sean; Matroule, Jean-Yves; Letesson, Jean-Jacques

    2015-12-01

    Brucellae are facultative intracellular pathogens. The recent development of methods and genetically engineered strains allowed the description of cell-cycle progression of Brucella abortus, including unipolar growth and the ordered initiation of chromosomal replication. B. abortus cell-cycle progression is coordinated with intracellular trafficking in the endosomal compartments. Bacteria are first blocked at the G1 stage, growth and chromosome replication being resumed shortly before reaching the intracellular proliferation compartment. The control mechanisms of cell cycle are similar to those reported for the bacterium Caulobacter crescentus, and they are crucial for survival in the host cell. The development of single-cell analyses could also be applied to other bacterial pathogens to investigate their cell-cycle progression during infection. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. The LifeCycle model

    DEFF Research Database (Denmark)

    Krink, Thiemo; Løvbjerg, Morten

    2002-01-01

    Adaptive search heuristics are known to be valuable in approximating solutions to hard search problems. However, these techniques are problem dependent. Inspired by the idea of life cycle stages found in nature, we introduce a hybrid approach called the LifeCycle model that simultaneously applies...

  16. Emissions from photovoltaic life cycles

    NARCIS (Netherlands)

    Fthenakis, V.M.; Kim, H.C.; Alsema, E.A.|info:eu-repo/dai/nl/073416258

    2008-01-01

    Photovoltaic (PV) technologies have shown remarkable progress recently in terms of annual production capacity and life cycle environmental performances, which necessitate timely updates of environmental indicators. Based on PV production data of 2004–2006, this study presents the life-cycle

  17. Economic growth and business cycles

    NARCIS (Netherlands)

    Canton, E.J.F.

    1997-01-01

    This thesis contains five essays on economic growth and business cycles. The main focus is on the interaction between economic growth and the cycle: is cyclical variability good or bad for the long-run rate of economic growth? The introduction aims to provide some empirical evidence for an

  18. Hamiltonian cycles in polyhedral maps

    Indian Academy of Sciences (India)

    We present a necessary and sufficient condition for existence of a contractible, non-separating and non-contractible separating Hamiltonian cycle in the edge graph of polyhedral maps on surfaces.We also present algorithms to construct such cycles whenever it exists where one of them is linear time and another is ...

  19. Credit cycles and macro fundamentals

    NARCIS (Netherlands)

    Koopman, S.J.; Kraeussl, R.G.W.; Lucas, A.; Monteiro, A.

    2009-01-01

    We use an intensity-based framework to study the relation between macroeconomic fundamentals and cycles in defaults and rating activity. Using Standard and Poor's U.S. corporate rating transition and default data over the period 1980-2005, we directly estimate the default and rating cycle from micro

  20. Cycling, modernity and national culture.

    NARCIS (Netherlands)

    Oosterhuis, Harry

    2016-01-01

    This historiographical essay provides an overview of extensive recent work on the history of cycling to show the diverse ways in which the bicycle was adopted and experienced across Western societies. Two key aspects are explored. Firstly, it discusses the complex relationship between cycling and

  1. Prospects for Predicting Cycle 24

    Indian Academy of Sciences (India)

    2016-01-27

    feeding' information about the polar field at the minima. Following this process, we find that our model fits the observed sunspot numbers of cycles 21–23 reasonably well and predicts that cycle 24 will be the weakest in a century.

  2. The water cycle for kids

    Science.gov (United States)

    Neno, Stephanie; Morgan, Jim; Zonolli, Gabriele; Perlman, Howard; Gonthier, Gerard

    2013-01-01

    The U.S. Geological Survey (USGS) and the Food and Agriculture Organization of the United Nations (FAO) have created a water-cycle diagram for use in elementary and middle schools. The diagram is available in many languages. This diagram is part of the USGS's Water Science School, in which the water cycle is described in detail.

  3. Fuel cycle optimization in PWR'S

    International Nuclear Information System (INIS)

    Castro Lobo, P.D. de; Amorim, E.S. do.

    1979-08-01

    Neutronics aspects of a reactor core throughout its cycle were investigated in a search for increasing in-core utilization of the residual fissile isotopes content in the cycle discharged disposal. The effects due to design modifications introduced at burnup levels near the end-of-cycle, in an equilibrium cycle condition, have indicated the possibility of a better in-core utilization of the residual fissile isotopes existing in the cycle discharged disposal. The potential benefits are significant to warranty an examination of the mechanical and thermal hydraulic involved. At convenient burnup levels, change in H 2 O/UO 2 volume ratio were introduced allowing an intense depletion of the residual fissile isotopes existing in assemblies with high exposures levels. (Author) [pt

  4. Transition cycles optimization for PWRs

    International Nuclear Information System (INIS)

    Kocic, A.; Dimitrijevic, Z.

    1981-01-01

    In this paper a selection of optimal reload strategy for the cycles of transition in PWRs has been discusses. First step is a selection of alternative reload batch sizes. A general reloading strategy can be established allowing variable number of fuel assemblies hold-out in the reactor storage pool. As a second step a neutronics calculation of transient cycles should be done to obtain feed enrichment and cycle lengths for each cycle. The same program also calculates region-wise burnup sharing each cycle and isotopics at discharge as data needed for economic calculation of full costs in the format of the program FUELCASH, which is used for the different strategy economic evaluation. (author)

  5. Thermodynamic Study of Multi Pressure HRSG in Gas/Steam Combined Cycle Power Plant

    Science.gov (United States)

    Sharma, Meeta; Singh, Onkar

    2018-01-01

    Combined cycle power plants have a combination of gas based topping cycle and steam based bottoming cycle through the use of Heat Recovery Steam Generator (HRSG). These HRSG may be either of single pressure (SP) or dual pressure (DP) or multiple pressure type. Here in this study thermodynamic analysis is carried out for optimal performance of HRSG using different types of HRSG layout for combined cycle efficiency improvement. Performance of single pressure HRSG and dual pressure HRSG, utilized in gas/steam combined cycle is analyzed and presented here. In comparison to single pressure, dual pressure HRSG offers 10 to 15% higher reduction in stack temperature due to greater heat recovery and thus improved plant efficiency.

  6. A New, Highly Improved Two-Cycle Engine

    Science.gov (United States)

    Wiesen, Bernard

    2008-01-01

    The figure presents a cross-sectional view of a supercharged, variable-compression, two-cycle, internal-combustion engine that offers significant advantages over prior such engines. The improvements are embodied in a combination of design changes that contribute synergistically to improvements in performance and economy. Although the combination of design changes and the principles underlying them are complex, one of the main effects of the changes on the overall engine design is reduced (relative to prior two-cycle designs) mechanical complexity, which translates directly to reduced manufacturing cost and increased reliability. Other benefits include increases in the efficiency of both scavenging and supercharging. The improvements retain the simplicity and other advantages of two-cycle engines while affording increases in volumetric efficiency and performance across a wide range of operating conditions that, heretofore have been accessible to four-cycle engines but not to conventionally scavenged two-cycle ones, thereby increasing the range of usefulness of the two-cycle engine into all areas now dominated by the four-cycle engine. The design changes and benefits are too numerous to describe here in detail, but it is possible to summarize the major improvements: Reciprocating Shuttle Inlet Valve The entire reciprocating shuttle inlet valve and its operating gear is constructed as a single member. The shuttle valve is actuated in a lost-motion arrangement in which, at the ends of its stroke, projections on the shuttle valve come to rest against abutments at the ends of grooves in a piston skirt. This shuttle-valve design obviates the customary complex valve mechanism, actuated from an engine crankshaft or camshaft, yet it is effective with every type of two-cycle engine, from small high-speed single cylinder model engines, to large low-speed multiple cylinder engines.

  7. Fuel management options to extend the IRIS reactor cycle

    International Nuclear Information System (INIS)

    Petrovic, B.; Franceschini, F.

    2004-01-01

    To optimize plant operation, reduce scheduled maintenance outage, and increase capacity factor, IRIS is designed to enable extended cycles of up to four years. However, due to the enrichment licensing limitation (less than 5% enriched uranium oxide) there is a tradeoff between the achievable cycle length and fuel utilization, i.e., the average fuel discharge burnup. The longest individual cycle may be achieved with the single-batch straight burn, but at the expense of a lower burnup. Considering the IRIS basic performance requirements, a cycle length in the range of three to four years is deemed desirable. This paper examines different fuel management options, i.e., the influence of the required cycle length on the corresponding reloading strategy, including a two-batch and a three-batch reloading. A reference two-batch core design has been developed for the first cycle, as well as for the transition cycles leading to equilibrium. Main core performance parameters are evaluated. This core design provides the framework for the safety analyses needed to prepare the IRIS safety evaluations. Alternate designs are also considered.(author)

  8. Limit cycles in quantum systems

    Energy Technology Data Exchange (ETDEWEB)

    Niemann, Patrick

    2015-04-27

    In this thesis we investigate Limit Cycles in Quantum Systems. Limit cycles are a renormalization group (RG) topology. When degrees of freedom are integrated out, the coupling constants flow periodically in a closed curve. The presence of limit cycles is restricted by the necessary condition of discrete scale invariance. A signature of discrete scale invariance and limit cycles is log-periodic behavior. The first part of this thesis is concerned with the study of limit cycles with the similarity renormalization group (SRG). Limit cycles are mainly investigated within conventional renormalization group frameworks, where degrees of freedom, which are larger than a given cutoff, are integrated out. In contrast, in the SRG potentials are unitarily transformed and thereby obtain a band-diagonal structure. The width of the band structure can be regarded as an effective cutoff. We investigate the appearance of limit cycles in the SRG evolution. Our aim is to extract signatures as well as the scaling factor of the limit cycle. We consider the 1/R{sup 2}-potential in a two-body system and a three-body system with large scattering lengths. Both systems display a limit cycle. Besides the frequently used kinetic energy generator we apply the exponential and the inverse generator. In the second part of this thesis, Limit Cycles at Finite Density, we examine the pole structure of the scattering amplitude for distinguishable fermions at zero temperature in the medium. Unequal masses and a filled Fermi sphere for each fermion species are considered. We focus on negative scattering lengths and the unitary limit. The properties of the three-body spectrum in the medium and implications for the phase structure of ultracold Fermi gases are discussed.

  9. How can a life cycle inventory parametric model streamline life cycle assessment in the wooden pallet sector?

    DEFF Research Database (Denmark)

    Niero, Monia; Di Felice, Francesco; Ren, Jingzheng

    2014-01-01

    ; these correlations can be used to improve the design of new wooden pallets.The conceptual scheme for defining the model is based on ISO14040-44 standards. First of all, the product system was defined identifying the life cycle of a generic wood pallet, as well as its life cycle stages. A list of independent......, as the information required for fulfilling the LCI are standard information about the features of the wooden pallet and its manufacturing process. The contribution analysis on the reference product revealed that the most contributing life cycle stages are wood and nails extraction and manufacturing (positive value......This study discusses the use of parameterization within the life cycle inventory (LCI) in the wooden pallet sector, in order to test the effectiveness of LCI parametric models to calculate the environmental impacts of similar products. Starting from a single case study, the objectives of this paper...

  10. Out-of-core fuel cycle optimization for nonequilibrium cycles

    International Nuclear Information System (INIS)

    Comes, S.A.; Turinsky, P.J.

    1988-01-01

    A methodology has been developed for determining the family of near-optimum fuel management schemes that minimize the levelized fuel cycle costs of a light water reactor over a multicycle planning horizon. Feed batch enrichments and sizes, burned batches to reinsert, and burnable poison loadings are determined for each cycle in the planning horizon. Flexibility in the methodology includes the capability to assess the economic benefits of various partially burned bath reload strategies as well as the effects of using split feed enrichments and enrichment palettes. Constraint limitations are imposed on feed enrichments, discharge burnups, moderator temperature coefficient, and cycle energy requirements

  11. Cycling infrastructure for reducing cycling injuries in cyclists.

    Science.gov (United States)

    Mulvaney, Caroline A; Smith, Sherie; Watson, Michael C; Parkin, John; Coupland, Carol; Miller, Philip; Kendrick, Denise; McClintock, Hugh

    2015-12-10

    Cycling is an attractive form of transport. It is beneficial to the individual as a form of physical activity that may fit more readily into an individual's daily routine, such as for cycling to work and to the shops, than other physical activities such as visiting a gym. Cycling is also beneficial to the wider community and the environment as a result of fewer motorised journeys. Cyclists are seen as vulnerable road users who are frequently in close proximity to larger and faster motorised vehicles. Cycling infrastructure aims to make cycling both more convenient and safer for cyclists. This review is needed to guide transport planning. To:1. evaluate the effects of different types of cycling infrastructure on reducing cycling injuries in cyclists, by type of infrastructure;2. evaluate the effects of cycling infrastructure on reducing the severity of cycling injuries in cyclists;3. evaluate the effects of cycling infrastructure on reducing cycling injuries in cyclists with respect to age, sex and social group. We ran the most recent search on 2nd March 2015. We searched the Cochrane Injuries Group Specialised Register, CENTRAL (The Cochrane Library), MEDLINE (OvidSP), Embase Classic + Embase(OvidSP), PubMed and 10 other databases. We searched websites, handsearched conference proceedings, screened reference lists of included studies and previously published reviews and contacted relevant organisations. We included randomised controlled trials, cluster randomised controlled trials, controlled before-after studies, and interrupted time series studies which evaluated the effect of cycling infrastructure (such as cycle lanes, tracks or paths, speed management, roundabout design) on cyclist injury or collision rates. Studies had to include a comparator, that is, either no infrastructure or a different type of infrastructure. We excluded studies that assessed collisions that occurred as a result of competitive cycling. Two review authors examined the titles and

  12. Single atom spintronics

    International Nuclear Information System (INIS)

    Sullivan, M. R.; Armstrong, J. N.; Hua, S. Z.; Chopra, H. D.

    2005-01-01

    Full text: Single atom spintronics (SASS) represents the ultimate physical limit in device miniaturization. SASS is characterized by ballistic electron transport, and is a fertile ground for exploring new phenomena. In addition to the 'stationary' (field independent) scattering centers that have a small and fixed contribution to total transmission probability of electron waves, domain walls constitute an additional and enhanced source of scattering in these magnetic quantum point contacts (QPCs), the latter being both field and spin-dependent. Through the measurement of complete hysteresis loops as a function of quantized conductance, we present definitive evidence of enhanced backscattering of electron waves by atomically sharp domain walls in QPCs formed between microfabricated thin films [1]. Since domain walls move in a magnetic field, the magnitude of spin-dependent scattering changes as the QPC is cycled along its hysteresis loop. For example, as shown in the inset in Fig. 1, from zero towards saturation in a given field direction, the resistance varies as the wall is being swept away, whereas the resistance is constant upon returning from saturation towards zero, since in this segment of the hysteresis loop no domain wall is present across the contact. The observed spin-valve like behavior is realized by control over wall width and shape anisotropy. This behavior also unmistakably sets itself apart from any mechanical artifacts; additionally, measurements made on single atom contacts provide an artifact-free environment [2]. Intuitively, it is simpler to organize the observed BMR data according to all possible transitions between different conductance plateaus, as shown by the dotted line in Fig. 1; the solid circles show experimental data for Co, which follows the predicted scheme. Requisite elements for the observation of the effect will be discussed in detail along with a review of state of research in this field. Practically, the challenge lies in making

  13. Thermodynamic Cycle and CFD Analyses for Hydrogen Fueled Air-breathing Pulse Detonation Engines

    Science.gov (United States)

    Povinelli, Louis A.; Yungster, Shaye

    2002-01-01

    This paper presents the results of a thermodynamic cycle analysis of a pulse detonation engine (PDE) using a hydrogen-air mixture at static conditions. The cycle performance results, namely the specific thrust, fuel consumption and impulse are compared to a single cycle CFD analysis for a detonation tube which considers finite rate chemistry. The differences in the impulse values were indicative of the additional performance potential attainable in a PDE.

  14. 78 FR 50317 - Special Conditions: Cessna Aircraft Company, Model J182T; Diesel Cycle Engine Installation

    Science.gov (United States)

    2013-08-19

    ... Motorisation Aeronautiques (SMA) Engines, Inc. SR305-230E-C1 which is a four-stroke, air cooled, diesel cycle... approved under Type Certificate No. 3A13, is an aluminum, four place, single engine airplane with a... obtained by multiplying the mean torque by a factor of four for diesel cycle engines. (1) If a factor of...

  15. The fuel cycle scoping system

    International Nuclear Information System (INIS)

    Dooley, G.D.; Malone, J.P.

    1986-01-01

    The Fuel Cycle Scoping System (FCSS) was created to fill the need for a scoping tool which provides the utilities with the ability to quickly evaluate alternative fuel management strategies, tails assay choices, fuel fabrication quotes, fuel financing alternatives, fuel cycle schedules, and other fuel cycle perturbations. The FCSS was specifically designed for PC's that support dBASE-III(TM), a relational data base software system by Ashton-Tate. However, knowledge of dBASE-III is not necessary in order to utilize the FCSS. The FCSS is menu driven and can be utilized as a teaching tool as well as a scoping tool

  16. Menstrual cycle and skin reactivity

    DEFF Research Database (Denmark)

    Agner, T; Damm, P; Skouby, S O

    1991-01-01

    The hypothesis was tested that a cyclic variation exists in skin reactivity to irritant stimuli. Twenty-nine healthy women with regular menstrual cycles were challenged with sodium lauryl sulfate as an irritant patch test at day 1 and at days 9 through 11 of the menstrual cycle. The skin response...... in the menstrual cycle as evaluated by visual scoring (p less than 0.05) as well as by measurement of transepidermal water loss (p less than 0.05) and edema formation (p less than 0.005)....

  17. Introducing Life Cycle Impact Assessment

    DEFF Research Database (Denmark)

    Hauschild, Michael Zwicky; Huijbregts, Mark AJ

    2015-01-01

    methodology projects and presents the international scientific discussions and methodological consensus attempts in consecutive working groups under the auspices of the Society of Environmental Toxicology and Chemistry (SETAC) as well as the UNEP/ SETAC Life Cycle Initiative, and the (almost) parallel......This chapter serves as an introduction to the presentation of the many aspects of life cycle impact assessment (LCIA) in this volume of the book series ‘LCA Compendium’. It starts with a brief historical overview of the development of life cycle impact assessment driven by numerous national LCIA...

  18. An application for impedance spectroscopy in the characterisation of the glass transition during the lyophilization cycle: the example of a 10% w/v maltodextrin solution.

    Science.gov (United States)

    Smith, Geoff; Arshad, Muhammad Sohail; Polygalov, Eugene; Ermolina, Irina

    2013-11-01

    Impedance spectroscopy has been used for the measurement of the glass transition of a 10 % maltodextrin solution contained within a glass vial, with externally attached electrodes. Features of the pseudo-relaxation process, associated with the composite impedance of the glass vial-solution assembly, were characterised by the peak amplitude, C(peak)(″), and peak frequency, f(peak), of the capacitance spectra and the equivalent circuit elements that model the impedance spectra (i.e. the solution resistance and solution capacitance) and monitored every 3 min during re-heating of the solution. The time derivatives of all four parameters studied provided a glass transition in close agreement with DSC measurements (-17 °C) and at a precision of ± 0.5 °C. The temperature dependencies of the solution resistance and peak frequency were then characterised with the Arrhenius and Vogel-Fulcher-Tammann fit functions, at temperatures below and above Tg, respectively. The energy of activation (below Tg) was estimated at ~20 kJ mol(-1), and the fragility index (If) of the glass forming liquid (above Tg) was estimated at 0.9. The significance of the fragility index to the development, optimisation and control of the freeze-drying cycle is highlighted. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Life-cycle cost analysis of adsorption cycles for desalination

    KAUST Repository

    Thu, Kyaw

    2010-08-01

    This paper presents the thermo-economic analysis of the adsorption desalination (AD) cycle that is driven by low-temperature waste heat from exhaust of industrial processes or renewable sources. The AD cycle uses an adsorbent such as the silica gel to desalt the sea or brackish water. Based on an experimental prototype AD plant, the life-cycle cost analysis of AD plants of assorted water production capacities has been simulated and these predictions are translated into unit cost of water production. Our results show that the specific energy consumption of the AD cycle is 1.38 kWh/m3 which is the lowest ever reported. For a plant capacity of 1000 m3/d, the AD cycle offers a unit cost of $0.457/m3 as compared to more than $0.9 for the average RO plants. Besides being cost-effective, the AD cycle is also environment-friendly as it emits less CO2 emission per m3 generated, typically 85% less, by comparison to an RO process. © 2010 Desalination Publications.

  20. Influence of the type of working fluid in the lower cycle and superheated steam parameters in the upper cycle on effectiveness of operation of binary power plant

    Directory of Open Access Journals (Sweden)

    Stachel Aleksander A.

    2015-03-01

    Full Text Available In the paper presented have been the results of the analysis of effectiveness of operation of binary power plant consisting of combined two Clausius-Rankine cycles, namely the binary cycle with water as a working fluid in the upper cycle and organic substance as a working fluid in the lower cycle, as well as a single fluid component power plant operating also in line with the C-R cycle for superheated steam, with water as a working fluid. The influence of the parameters of superheated steam in the upper cycle has been assessed as well as the type of working fluid in the lower cycle. The results of calculations have been referred to the single-cycle classical steam power plant operating at the same parameters of superheated steam and the same mass flow rate of water circulating in both cycles. On the basis of accomplished analysis it has been shown that the binary power plant shows a greater power with respect to the reference power plant.