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Sample records for heating solid quark

  1. Quarks

    Shekhter, V [AN SSSR, Leningrad. Inst. Yadernoj Fiziki

    1981-04-01

    The history is described of the concept of quarks, ie., hypothetical particles of which,hadrons (strongly interacting particles) are believed to consist. The quark properties differ from those of known elementary particles. The electric charge of quarks is 1/3 and 2/3 of the electron charge and they obviously only exist inside hadrons. Quark existence is generally recognized because it has been confirmed by experimental verification of predictions made using a quark model.

  2. Heat capacity of solid parahydrogen

    Bagatskij, M I; Minchina, I Ya; Manzhelij, V G [AN Ukrainskoj SSR, Kharkov. Fiziko-Tekhnicheskij Inst. Nizkikh Temperatur

    1984-10-01

    A vacuum adiabatic calorimeter has been developed to investigate cryocrystals and their solutions in the range 0.4-300 K. Heat capacity of hydrogen with the orthomodification concentration 5 x 10/sup -3/ at.% between 0.5 and 8 K has been investigated. The limiting Debye temperature at T ..-->.. 0 has been obtained: (THETA/sub 0/=118.5 +- 0.5 K). It has been shown that heat capacity of solid parahydrogen, as that of other cryocrystals with the central interaction and closely packed lattices (/sup 4/He, Ne, Ar, Kr, Xe), low temperatures is given by the universal relation proposed by Barron and Morrison Csub(V) AT/sup 3/(1+..cap alpha../sub 1/(T/THETA/sub 0/)/sup 2/ + ..cap alpha../sub 2/(T/THETA/sub 0/)/sup 4/ ...). The effect of the sample time prehistory on the experimental heat capacity values of hydrogen with g.21 at.% orthomodification has been studied, and the times during which configurational equilibration in this solution is reached have been estimated.

  3. Utilization of heat of finely divided solids

    1951-11-05

    A method pr preconditioning subdivided solids subjected to a high-temperature treatment in a high-temperature treating zone, comprises transferring a portion of the sensible heat of hot, subdivided, treated solids withdrawn from said treating zone, at a relatively high temperature level to said subdivided solids to be preconditioned, transferring another portion of said sensible heat at a relatively low temperature level to a material vaporizable at said low temperature level to generate a fluidizing medium and fluidizing said subdivided withdrawn solids by means of said fluidizing medium to improve the heat-transfer characteristics of said withdrawn solids.

  4. Heating (Gapless) Color-Flavor Locked Quark Matter

    Fukushima, Kenji; Kouvaris, Christoforos; Rajagopal, Krishna

    2005-01-01

    We explore the phase diagram of neutral quark matter at high baryon density as a function of the temperature T and the strange quark mass Ms. At T=0, there is a sharp distinction between the insulating color-flavor locked (CFL) phase, which occurs where Ms^2/mu 0 and Delta_2->0) cross. Because we...

  5. RX J1856.5-3754: A Strange Star with Solid Quark Surface?

    Zhang, Xiaoling; Xu, Renxin; Zhang, Shuangnan

    2003-01-01

    The featureless spectra of isolated 'neutron stars' may indicate that they are actually bare strange stars but a definitive conclusion on the nature of the compact objects cannot be reached until accurate and theoretically calculated spectra of the bare quark surface are known. However due to the complex nonlinearity of quantum chromodynamics it is almost impossible to present a definitive and accurate calculation of the density-dominated quark-gluon plasma from the first principles. Nevertheless it was suggested that cold quark matter with extremely high baryon density could be in a solid state. Within the realms of this possibility we have fitted the 500ks Chandra LETG/HRC data for the brightest isolated neutron star RX 51856.5-3754 with a phenomenological spectral model and found that electric conductivity of quark matter on the stellar surface is about 1.5 x 10(exp 16)/s.

  6. Solid state radiative heat pump

    Berdahl, P.H.

    1984-09-28

    A solid state radiative heat pump operable at room temperature (300 K) utilizes a semiconductor having a gap energy in the range of 0.03-0.25 eV and operated reversibly to produce an excess or deficit of change carriers as compared equilibrium. In one form of the invention an infrared semiconductor photodiode is used, with forward or reverse bias, to emit an excess or deficit of infrared radiation. In another form of the invention, a homogenous semiconductor is subjected to orthogonal magnetic and electric fields to emit an excess or deficit of infrared radiation. Three methods of enhancing transmission of radiation the active surface of the semiconductor are disclosed. In one method, an anti-refection layer is coated into the active surface of the semiconductor, the anti-reflection layer having an index of refraction equal to the square root of that of the semiconductor. In the second method, a passive layer is speaced trom the active surface of the semiconductor by a submicron vacuum gap, the passive layer having an index of refractive equal to that of the semiconductor. In the third method, a coupler with a paraboloid reflecting surface surface is in contact with the active surface of the semiconductor, the coupler having an index of refraction about the same as that of the semiconductor.

  7. Solid0Core Heat-Pipe Nuclear Batterly Type Reactor

    Ehud Greenspan

    2008-09-30

    This project was devoted to a preliminary assessment of the feasibility of designing an Encapsulated Nuclear Heat Source (ENHS) reactor to have a solid core from which heat is removed by liquid-metal heat pipes (HP).

  8. Solid-Solid Vacuum Regolith Heat-Exchanger for Oxygen Production, Phase I

    National Aeronautics and Space Administration — This SBIR Phase-1 project will demonstrate the feasibility of using a novel coaxial counterflow solid-solid heat exchanger to recover heat energy from spent regolith...

  9. Postaccident heat removal. II. Heat transfer from an internally heated liquid to a melting solid

    Faw, R.E.; Baker, L. Jr.

    1976-01-01

    Microwave heating has been used in studies of heat transfer from a horizontal layer of internally heated liquid to a melting solid. Experiments were designed to simulate heat transfer and meltthrough processes of importance in the analysis of postaccident heat removal capabilities of nuclear reactors. Glycerin, heated by 2.45-GHz microwave radiation, was used to simulate molten fuel. Paraffin wax was used to simulate a melting barrier confining the fuel. Experimentally measured heat fluxes and melting rates were consistent with a model based on downward heat transfer by conduction through a stagnant liquid layer and upward heat transfer augmented by natural convection. Melting and displacement of the barrier material occurred by upward-moving droplets randomly distributed across the melting surface. Results indicated that the melting and displacement process had no effect on the heat transfer process

  10. Developing and modelling of ohmic heating for solid food products

    Feyissa, Aberham Hailu; Frosch, Stina

    Heating of solid foods using the conventional technologies is time-consuming due to the fact that heat transfer is limited by internal conduction within the product. This is a big challenge to food manufactures who wish to heat the product faster to the desired core temperature and to ensure more...... uniform quality across the product. Ohmic heating is one of the novel technologies potentially solving this problem by allowing volumetric heating of the product and thereby reducing or eliminating temperature gradients within the product. However, the application of ohmic heating for solid food products...... such as meat and seafood is not industrially utilized yet. Therefore, the aim of the current work is to model and develop the ohmic heating technology for heating of solid meat and seafood. A 3D mathematical model of coupled heat transfer and electric field during ohmic heating of meat products has been...

  11. Heat transfer across the interface between nanoscale solids and gas.

    Cheng, Chun; Fan, Wen; Cao, Jinbo; Ryu, Sang-Gil; Ji, Jie; Grigoropoulos, Costas P; Wu, Junqiao

    2011-12-27

    When solid materials and devices scale down in size, heat transfer from the active region to the gas environment becomes increasingly significant. We show that the heat transfer coefficient across the solid-gas interface behaves very differently when the size of the solid is reduced to the nanoscale, such as that of a single nanowire. Unlike for macroscopic solids, the coefficient is strongly pressure dependent above ∼10 Torr, and at lower pressures it is much higher than predictions of the kinetic gas theory. The heat transfer coefficient was measured between a single, free-standing VO(2) nanowire and surrounding air using laser thermography, where the temperature distribution along the VO(2) nanowire was determined by imaging its domain structure of metal-insulator phase transition. The one-dimensional domain structure along the nanowire results from the balance between heat generation by the focused laser and heat dissipation to the substrate as well as to the surrounding gas, and thus serves as a nanoscale power-meter and thermometer. We quantified the heat loss rate across the nanowire-air interface, and found that it dominates over all other heat dissipation channels for small-diameter nanowires near ambient pressure. As the heat transfer across the solid-gas interface is nearly independent of the chemical identity of the solid, the results reveal a general scaling relationship for gaseous heat dissipation from nanostructures of all solid materials, which is applicable to nanoscale electronic and thermal devices exposed to gaseous environments.

  12. Transfer of heat to fluidized-solids beds

    1952-10-16

    The improvement in the method described and claimed in patent application 14,363/47 (136,186) for supplying heat to a dense turbulent mass of solid fluidized by a gas flowing upwardly therethrough and subjected to a high temperature in a treating zone, by heat transfer through heat-transfer surfaces of heat-transfer elements in contact with the said turbulent mass of finely divided solid and heated by means of a fluid heating medium, including burning fuels comprising contacting the said heat-transfer surfaces with a fuel and a combustion supporting gas under such conditions that the combustion of the fuel is localized in the heat-transfer element near the point of entry of the fuel and combustion-supporting gas and a substantial temperature gradient is maintained along the path of said fuel combustion-supporting gas and combustion products through the said heat-transfer element.

  13. Preparation and characterization of a novel polymeric based solid-solid phase change heat storage material

    Xi Peng; Gu Xiaohua; Cheng Bowen; Wang Yufei

    2009-01-01

    Here we reported a two-step procedure for preparing a novel polymeric based solid-solid phase change heat storage material. Firstly, a copolymer monomer containing a polyethylene glycol monomethyl ether (MPEG) phase change unit and a vinyl unit was synthesized via the modification of hydrogen group of MPEG. Secondly, by copolymerization of the copolymer monomer and phenyl ethylene, a novel polymeric based solid-solid phase change heat storage material was prepared. The composition, structure and properties of the novel polymeric based solid-solid phase change material were characterized by IR, 1 H NMR, DSC, WAXD, and POM, respectively. The results show that the novel polymeric based solid-solid phase change material possesses of excellent crystal properties and high phase change enthalpy.

  14. MODELING OF TEMPERATURE FIELDS IN A SOLID HEAT ACCUMULLATORS

    S. S. Belimenko

    2016-10-01

    Full Text Available Purpose. Currently, one of the priorities of energy conservation is a cost savings for heating in commercial and residential buildings by the stored thermal energy during the night and its return in the daytime. Economic effect is achieved due to the difference in tariffs for the cost of electricity in the daytime and at night. One of the most common types of devices that allow accumulating and giving the resulting heat are solid heat accumulators. The main purpose of the work: 1 software development for the calculation of the temperature field of a flat solid heat accumulator, working due to the heat energy accumulation in the volume of thermal storage material without phase transition; 2 determination the temperature distribution in its volumes at convective heat transfer. Methodology. To achieve the study objectives a heat transfer theory and Laplace integral transform were used. On its base the problems of determining the temperature fields in the channels of heat accumulators, having different cross-sectional shapes were solved. Findings. Authors have developed the method of calculation and obtained solutions for the determination of temperature fields in channels of the solid heat accumulator in conditions of convective heat transfer. Temperature fields over length and thickness of channels were investigated. Experimental studies on physical models and industrial equipment were conducted. Originality. For the first time the technique of calculating the temperature field in the channels of different cross-section for the solid heat accumulator in the charging and discharging modes was proposed. The calculation results are confirmed by experimental research. Practical value. The proposed technique is used in the design of solid heat accumulators of different power as well as full-scale production of them was organized.

  15. Creeping Viscous Flow around a Heat-Generating Solid Sphere

    Krenk, Steen

    1981-01-01

    The velocity field for creeping viscous flow around a solid sphere due to a spherically symmetric thermal field is determined and a simple thermal generalization of Stokes' formula is obtained. The velocity field due to an instantaneous heat source at the center of the sphere is obtained in closed...... form and an application to the storage of heat-generating nuclear waste is discussed....

  16. Heat pipes and solid sorption transformations fundamentals and practical applications

    Vasiliev, LL

    2013-01-01

    Developing clean energy and utilizing waste energy has become increasingly vital. Research targeting the advancement of thermally powered adsorption cooling technologies has progressed in the past few decades, and the awareness of fuel cells and thermally activated (heat pipe heat exchangers) adsorption systems using natural refrigerants and/or alternatives to hydrofluorocarbon-based refrigerants is becoming ever more important. Heat Pipes and Solid Sorption Transformations: Fundamentals and Practical Applications concentrates on state-of-the-art adsorption research and technologies for releva

  17. Problems of the heat transfer during the irradiation of solids

    Jahn, G.

    1981-03-01

    This report deals with the thermal problems during the irradiation of solids. Analytical and constructive solutions are outlined by some examples. Two cases are looked at: 1) the samples and the equipment are warmed up during irradiation. Thus they have to be cooled which yields a negative heat flux direction. 2) The samples shall have a suitable temperature higher than room temperature. Thus they have to be heated which yields a positive heat flux direction. (BHO)

  18. Estimating Nitrogen Availability of Heat-Dried Bio solids

    Cogger, C.G.; Bary, A.I.; Myhre, E.A.

    2011-01-01

    As heat-dried bio solids become more widely produced and marketed, it is important to improve estimates of N availability from these materials. Objectives were to compare plant-available N among three different heat-dried bio solids and determine if current guidelines were adequate for estimating application rates. Heat-dried bio solids were surface applied to tall fescue (Festuca arundinacea Schreb.) in Washington State, USA, and forage yield and N uptake measured for two growing seasons following application. Three rates of urea and a zero-N control were used to calculate N fertilizer efficiency regressions. Application year plant-available N (estimated as urea N equivalent) for two bio solids exceeded 60% of total N applied, while urea N equivalent for the third bio solids was 45%. Residual (second-year) urea N equivalent ranged from 5 to 10%. Guidelines for the Pacific Northwest USA recommend mineralization estimates of 35 to 40% for heat-dried bio solids, but this research shows that some heat-dried materials fall well above that range.

  19. The Little Heat Engine: Heat Transfer in Solids, Liquids and Gases

    Robitaille P.-M.

    2007-10-01

    Full Text Available In this work, an introductory exposition of the laws of thermodynamics and radiative heat transfer is presented while exploring the concepts of the ideal solid, the lattice, and the vibrational, translational, and rotational degrees of freedom. Analysis of heat transfer in this manner helps scientists to recognize that the laws of thermal radiation are strictly applicable only to the ideal solid. On the Earth, such a solid is best represented by either graphite or soot. Indeed, certain forms of graphite can approach perfect absorption over a relatively large frequency range. Nonetheless, in dealing with heat, solids will eventually sublime or melt. Similarly, liquids will give way to the gas phase. That thermal conductivity eventually decreases in the solid signals an inability to further dissipate heat and the coming breakdown of Planck’s law. Ultimately, this breakdown is reflected in the thermal emission of gases. Interestingly, total gaseous emissivity can de- crease with increasing temperature. Consequently, neither solids, liquids, or gases can maintain the behavior predicted by the laws of thermal emission. Since the laws of thermal emission are, in fact, not universal, the extension of these principles to non-solids constitutes a serious overextension of the work of Kirchhoff, Wien, Stefan and Planck.

  20. Heat transfer problems in gas-cooled solid blankets

    Fillo, J.A.; Powell, J.R.

    1976-01-01

    In all fusion reactors using the deuterium-tritium fuel cycle, a large fraction approximately 80 percent of the fusion energy will be released as approximately 14 MeV neutrons which must be slowed down in a relatively thick blanket surrounding the plasma, thereby, converting their kinetic energy to high temperature heat which can be continuously removed by a coolant stream and converted in part to electricity in a conventional power turbine. Because of the primary goal of achieving minimum radioactivity, to date Brookhaven blanket concepts have been restricted to the use of some form of solid lithium, with inert gas-cooling and in some design cases, water-cooling of the shell structure. Aluminum and graphite have been identified as very promising structural materials for fusion blankets, and conceptual designs based on these materials have been made. Depending on the thermal loading on the ''first'' wall which surrounds the plasma as well as blanket design, heat transfer problems may be noticeably different in gas-cooled solid blankets. Approaches to solution of heat removal problems as well as explanation of: (a) the after-heat problems in blankets; (b) tritium breeding in solids; and (c) materials selection for radiation shields relative to the minimum activity blanket efforts at Brookhaven are discussed

  1. Non Debye approximation on specific heat of solids

    Bhattacharjee, Ruma; Das, Anamika; Sarkar, A.

    2018-05-01

    A simple non Debye frequency spectrum is proposed. The normalized frequency spectrum is compared to that of Debye spectrum. The proposed spectrum, provides a good account of low frequency phonon density of states, which gives a linear temperature variation at low temperature in contrast to Debye T3 law. It has been analyzed that the proposed model provides a good account of excess specific heat for nanostructure solid.

  2. Quark-quark interactions

    Jacob, M.

    1982-01-01

    This chapter discusses interactions only at the constituent level, as observed in hadron-hadron collisions. It defines quarks and gluons as constituents of the colliding hadrons, reviews some applications of perturbative OCD, discussing in turn lepton pair production, which in lowest order approximation corresponds to the Drell-Yan process. It investigates whether quark-quark interactions could not lead to some new color structure different from those prevalent for known baryons and mesons, which could be created in hadron interactions, and whether color objects (not specifically quarks or gluons) could not appear as free particles. Discussed is perturbative QCD in hadron collisions; the quark approach to soft processes; and new color structures. It points out that perturbative QCD has been at the origin of much progress in the understanding of hadron interactions at the constituent level

  3. High-temperature process heat reactor with solid coolant and radiant heat exchange

    Alekseev, A.M.; Bulkin, Yu.M.; Vasil'ev, S.I.

    1984-01-01

    The high temperature graphite reactor with the solid coolant in which heat transfer is realized by radiant heat exchange is described. Neutron-physical and thermal-technological features of the reactor are considered. The reactor vessel is made of sheet carbon steel in the form of a sealed rectangular annular box. The moderator is a set of graphite blocks mounted as rows of arched laying Between the moderator rows the solid coolant annular layings made of graphite blocks with high temperature nuclear fuel in the form of coated microparticles are placed. The coolant layings are mounted onto ring movable platforms, the continuous rotation of which is realizod by special electric drives. Each part of the graphite coolant laying consecutively passes through the reactor core neutron cut-off zones and technological zone. In the core the graphite is heated up to the temperature of 1350 deg C sufficient for effective radiant heat transfer. In the neutron cut-off zone the chain reaction and further graphite heating are stopped. In the technological zone the graphite transfers the accumulated heat to the walls of technological channels in which the working medium moves. The described reactor is supposed to be used in nuclear-chemical complex for ammonia production by the method of methane steam catalytic conversion

  4. Applicability of Solid Solution Heat Treatments to Aluminum Foams

    Miguel Rodríguez-Pérez

    2012-12-01

    Full Text Available Present research work evaluates the influence of both density and size on the treatability of Aluminum-based (6000 series foam-parts subjected to a typical solid solution heat treatment (water quenching. The results are compared with those obtained for the bulk alloy, evaluating the fulfilment of cooling requirements. Density of the foams was modeled by tomography analysis and the thermal properties calculated, based on validated density-scaled models. With this basis, cooling velocity maps during water quenching were predicted by finite element modeling (FEM in which boundary conditions were obtained by solving the inverse heat conduction problem. Simulations under such conditions have been validated experimentally. Obtained results address incomplete matrix hardening for foam-parts bigger than 70 mm in diameter with a density below 650 kg/m3. An excellent agreement has been found in between the predicted cooling maps and final measured microhardness profiles.

  5. Pyrolysis Characteristics of Corn Stalk with Solid Heat Carrier

    Min Guo

    2015-05-01

    Full Text Available Pyrolysis of corn stalk with a solid heat carrier was studied under temperatures ranging from 430 to 620 °C. The solid heat carrier used was high-temperature ash from a CFB boiler. The yields of three products and their characteristics were investigated. Moreover, the distributions of sulfur and nitrogen in the products were determined. The results indicate that with increasing temperature, the char yield decreased, gas yield increased, and calorific value of the gas increased from 10.13 to 16.65 MJ/m3. The yield of bio-oil reached a maximum, 14.24 wt.%, at 510 °C. Light-oil in the bio-oil accounted for more than 69.12 wt.%. The elemental composition of the char and char ash were analyzed. The distribution of sulfur and nitrogen in the char decreased to 60.44 and 46.52 wt.%, respectively, depending on the raw materials used. These results provide basic data for the possible industrial application of corn stalk.

  6. The heat-transfer performance of gas—solid trickle flow over a regularly stacked packing

    Verver, A.B.; van Swaaij, Willibrordus Petrus Maria

    1986-01-01

    The heat-transfer behaviour of a countercurrent gas—solid trickle flow contactor is studied, using coarse sand particles as the solids phase. Experimental data on the overall heat-transfer rate constant between the gas flow and the solid particle flow were obtained in a 0.15 m square cross-section

  7. Heat-Assisted Multiferroic Solid-State Memory.

    Lepadatu, Serban; Vopson, Melvin M

    2017-08-25

    A heat-assisted multiferroic solid-state memory design is proposed and analysed, based on a PbNbZrSnTiO₃ antiferroelectric layer and Ni 81 Fe 19 magnetic free layer. Information is stored as magnetisation direction in the free layer of a magnetic tunnel junction element. The bit writing process is contactless and relies on triggering thermally activated magnetisation switching of the free layer towards a strain-induced anisotropy easy axis. A stress is generated using the antiferroelectric layer by voltage-induced antiferroelectric to ferroelectric phase change, and this is transmitted to the magnetic free layer by strain-mediated coupling. The thermally activated strain-induced magnetisation switching is analysed here using a three-dimensional, temperature-dependent magnetisation dynamics model, based on simultaneous evaluation of the stochastic Landau-Lifshitz-Bloch equation and heat flow equation, together with stochastic thermal fields and magnetoelastic contributions. The magnetisation switching probability is calculated as a function of stress magnitude and maximum heat pulse temperature. An operating region is identified, where magnetisation switching always occurs, with stress values ranging from 80 to 180 MPa, and maximum temperatures normalised to the Curie temperature ranging from 0.65 to 0.99.

  8. Solid-Core Heat-Pipe Nuclear Batterly Type Reactor

    Ehud Greenspan

    2008-01-01

    This project was devoted to a preliminary assessment of the feasibility of designing an Encapsulated Nuclear Heat Source (ENHS) reactor to have a solid core from which heat is removed by liquid-metal heat pipes (HP). Like the SAFE 400 space nuclear reactor core, the HPENHS core is comprised of fuel rods and HPs embedded in a solid structure arranged in a hexagonal lattice in a 3:1 ratio. The core is oriented horizontally and has a square rather cylindrical cross section for effective heat transfer. The HPs extend from the two axial reflectors in which the fission gas plena are embedded and transfer heat to an intermediate coolant that flows by natural-circulation. The HP-ENHS is designed to preserve many features of the ENHS including 20-year operation without refueling, very small excess reactivity throughout life, natural circulation cooling, walkaway passive safety, and robust proliferation resistance. The target power level and specific power of the HP-ENHS reactor are those of the reference ENHS reactor. Compared to previous ENHS reactor designs utilizing a lead or lead-bismuth alloy natural circulation cooling system, the HP-ENHS reactor offers a number of advantageous features including: (1) significantly enhanced passive decay heat removal capability; (2) no positive void reactivity coefficients; (3) relatively lower corrosion of the cladding (4) a core that is more robust for transportation; (5) higher temperature potentially offering higher efficiency and hydrogen production capability. This preliminary study focuses on five areas: material compatibility analysis, HP performance analysis, neutronic analysis, thermal-hydraulic analysis and safety analysis. Of the four high-temperature structural materials evaluated, Mo TZM alloy is the preferred choice; its upper estimated feasible operating temperature is 1350 K. HP performance is evaluated as a function of working fluid type, operating temperature, wick design and HP diameter and length. Sodium is the

  9. Heat capacity and solid solubility of iron in scandium

    Tsang, T.-W.E.

    1981-01-01

    The maximum solid solubility of iron in scandium was determined to be between 50 and 85 at.ppm in the as-cast condition. As the concentration of iron increases, it segregates along the grain boundary, as is evident from optical metallography and electron microprobe examinations. Annealing also causes the iron dissolved in scandium to separate out and cluster along the grain boundary. Heat capacity measurements show an anomaly in the C/T versus T 2 plots for iron concentrations of 19 at.ppm or greater. For iron dissolved in solid scandium the excess entropy due to the iron impurity is in agreement with the theoretical prediction of ck ln(2S + 1) for an impurity-conduction electron (Kondo) interaction, but is 4 - 8 times larger than the theoretical prediction when iron segregates along the grain boundary. Furthermore, our results suggest that most of the previously reported low temperature physical properties of scandium are probably in error because of either iron impurity-conduction electron interactions or Fe-Fe interactions in the precipitated second-phase Sc-Fe compound. (Auth.)

  10. Instability heating of solid-fiber Z pinches

    Riley, R.A. Jr.

    1994-02-01

    The Los Alamos High Density Z Pinch-II (HDZP-II) facility is used to study the dynamics of z-pinch plasmas generated from solid fibers of deuterated polyethylene CD 2 with a range in radii of 3--60 μm. HDZP-II is a pulsed-power generator that delivers a current that rises to 700 kA in 100 ns through an inductive load. A multiframe circular schlieren records the evolution of the shape and size of the plasma on seven images taken at 10-ns intervals. These circular-schlieren images show very strong m=0 instability at the onset of current and a rapid radial expansion of the plasma. No higher-order instabilities are observed. An interferometer is used to infer the electron density and electron line density, giving a measure of the fraction of plasma contained within the outline of the circular-schlieren image at one time during the multiframe sequence. A three-channel x-ray crystal-reflection spectrometer provides the time-resolved, spatially-averaged electron temperature. The magnitude of the x-ray emission at these energies also gives qualitative information about the electron temperature and density at late times. A lower bound on the ion temperature is inferred from the particle pressure needed to balance the magnetic field pressure. The ion temperature rose above that of the electrons, strongly suggesting an additional heating term that puts energy directly into the ions. An ion heating term is proposed to explain the observed rapid radial expansion and elevated ion temperatures. This heating term is based on the assumption that the observed m=0 instabilities reconnect, enclosing magnetic flux which degenerates into turbulence in the plasma. A 0-D simulation is developed to investigate the relevance of different physical models to the data presented

  11. Instability heating of solid-fiber Z pinches

    Riley, Jr., Ronald Alan [Univ. of California, San Diego, CA (United States)

    1994-02-01

    The Los Alamos High Density Z Pinch-II (HDZP-II) facility is used to study the dynamics of z-pinch plasmas generated from solid fibers of deuterated polyethylene CD2 with a range in radii of 3--60 μm. HDZP-II is a pulsed-power generator that delivers a current that rises to 700 kA in 100 ns through an inductive load. A multiframe circular schlieren records the evolution of the shape and size of the plasma on seven images taken at 10-ns intervals. These circular-schlieren images show very strong m=0 instability at the onset of current and a rapid radial expansion of the plasma. No higher-order instabilities are observed. An interferometer is used to infer the electron density and electron line density, giving a measure of the fraction of plasma contained within the outline of the circular-schlieren image at one time during the multiframe sequence. A three-channel x-ray crystal-reflection spectrometer provides the time-resolved, spatially-averaged electron temperature. The magnitude of the x-ray emission at these energies also gives qualitative information about the electron temperature and density at late times. A lower bound on the ion temperature is inferred from the particle pressure needed to balance the magnetic field pressure. The ion temperature rose above that of the electrons, strongly suggesting an additional heating term that puts energy directly into the ions. An ion heating term is proposed to explain the observed rapid radial expansion and elevated ion temperatures. This heating term is based on the assumption that the observed m=0 instabilities reconnect, enclosing magnetic flux which degenerates into turbulence in the plasma. A 0-D simulation is developed to investigate the relevance of different physical models to the data presented.

  12. Perspectives of advanced thermal management in solar thermochemical syngas production using a counter-flow solid-solid heat exchanger

    Falter, Christoph; Sizmann, Andreas; Pitz-Paal, Robert

    2017-06-01

    A modular reactor model is presented for the description of solar thermochemical syngas production involving counter-flow heat exchangers that recuperate heat from the solid phase. The development of the model is described including heat diffusion within the reactive material as it travels through the heat exchanger, which was previously identified to be a possibly limiting factor in heat exchanger design. Heat transfer within the reactive medium is described by conduction and radiation, where the former is modeled with the three-resistor model and the latter with the Rosseland diffusion approximation. The applicability of the model is shown by the analysis of heat exchanger efficiency for different material thicknesses and porosities in a system with 8 chambers and oxidation and reduction temperatures of 1000 K and 1800 K, respectively. Heat exchanger efficiency is found to rise strongly for a reduction of material thickness, as the element mass is reduced and a larger part of the elements takes part in the heat exchange process. An increase of porosity enhances radiation heat exchange but deteriorates conduction. The overall heat exchange in the material is improved for high temperatures in the heat exchanger, as radiation dominates the energy transfer. The model is shown to be a valuable tool for the development and analysis of solar thermochemical reactor concepts involving heat exchange from the solid phase.

  13. Slow heat release - solid fuel stove with acetat-trihydrate heat storage sodium; Slow heat release - Braendeovn med salthydratvarmelager

    Zielke, U.; Bjerrum, M.; Noergaard, T. (Teknologisk Institut, Aarhus (Denmark))

    2012-07-01

    Of the 700,000 solid fuel stoves in Denmark, 600,000 are installed in permanent residences, and 100,000 are installed in summer cottages. Recent examinations have shown that in the heating season, these stoves contribute with a not negligible share of air pollution in the cities. The reason is often inexpedient firing and an inappropriate performance of the stove. In many cases the thermal output of the stove exceeds the heating demand of a modern residence; and the user typically reduces the stove's combustion air supply with the purpose of lowering the temperature of the accommodation space. The result is a sooting combustion followed by undesired and environmentally damaging emissions. In worst case the user fires throughout the night reducing the air to an absolutely minimum. In these situations the fuel smoulders all night, and the stove emits large amounts of undesirable and unhealthy emissions. By constructing the stove with a heat storage that can accumulate the heat from the stove and emit the heat later (when not firing), the problem with the unhealthy ''night firings'' should be eliminated. The project started with a pre-examination regarding suitable materials for a heat storage and a literature study of the subject. By using an OGC material, in this case sodiumacetat-trihydrat, the weight of the stove, in spite of the heat storage, could be held within reasonable frames, since 130 kg PCM can contain the same heat amount as 1,200 kg stone. The great challenge was to compensate for PCM's poor heat conductivities, to distribute the heat in the whole heat storage, making it melt regularly without generating local boiling. This problem was solved by construction measures. The system with sodiumacetat-trihydrat, which melts by 58 deg. C, came to function satisfactorily. 14 hours after the last firing, the temperature of the heat storage was 30 deg. C. The tests with PCM were followed by an extensive emission measuring program

  14. Pre-critical phenomena of two-flavor color superconductivity in heated quark matter. Diquark-pair fluctuations and non-Fermi liquid behavior

    Kitazawa, Masakiyo; Kunihiro, Teiji; Koide, Tomoi; Nemoto, Yukio

    2005-01-01

    We investigate the fluctuations of the diquark-pair field and their effects on observables above the critical temperature T c in two-flavor color superconductivity (CSC) at moderate density using a Nambu-Jona-Lasinio-type effective model of QCD. Because of the strong-coupling nature of the dynamics, the fluctuations of the pair field develop a collective mode, which has a prominent strength even well above T c . We show that the collective mode is actually the soft mode of CSC. We examine the effects of the pair fluctuations on the specific heat and the quark spectrum for T above but close to T c . We find that the specific heat exhibits singular behavior because of the pair fluctuations, in accordance with the general theory of second-order phase transitions. The quarks display a typical non-Fermi liquid behavior, owing to the coupling with the soft mode, leading to a pseudo-gap in the density of states of the quarks in the vicinity of the critical point. Some experimental implications of the precursory phenomena are also discussed. (author)

  15. A matter of quarks

    Anon.

    1987-01-01

    Quarks are understood to interact through the 'colour' force, carried by gluons. Under normal conditions these quarks are confined - frozen together in 'colourless' states such as protons, neutrons and other strongly interacting particles. However if the quarks are compressed tightly together and/or are 'heated' by increasing their energy, they should eventually break loose from their colour bonds to form a new kind of matter – the so-called quark-gluon plasma. Although QGP has not yet been synthesized in the Laboratory, it was most likely the stuff of the Universe 10 -5 second after the Big Bang. Thus the search for this 'new' matter is attracting a growing number of physicists, theorists and experimenters from both the particle physics and nuclear physics fields

  16. A finite volume procedure for fluid flow, heat transfer and solid-body stress analysis

    Jagad, P. I.; Puranik, B. P.; Date, A. W.

    2018-01-01

    A unified cell-centered unstructured mesh finite volume procedure is presented for fluid flow, heat transfer and solid-body stress analysis. An in-house procedure (A. W. Date, Solution of Transport Equations on Unstructured Meshes with Cell

  17. Microwave heating in solid-phase peptide synthesis

    Pedersen, Søren Ljungberg; Shelton, Anne Pernille Tofteng; Malik, Leila

    2012-01-01

    synthesis, precise microwave irradiation to heat the reaction mixture during coupling and N(a)-deprotection has become increasingly popular. It has often provided dramatic reductions in synthesis times, accompanied by an increase in the crude peptide purity. Microwave heating has been proven especially...... relevant for sequences which might form ß-sheet type structures and for sterically difficult couplings. The beneficial effect of microwave heating appears so far to be due to the precise nature of this type of heating, rather than a peptide-specific microwave effect. However, microwave heating...... in microwave heating for peptide synthesis, with a focus on systematic studies and general protocols, as well as important applications. The assembly of ß-peptides, peptoids and pseudopeptides are also evaluated in this critical review (254 references)....

  18. Heat and water transfer in a rotating drum containing solid substrate particles

    Schutyser, M.A.I.; Weber, F.J.; Briels, W.J.; Rinzema, A.; Boom, R.M.

    2003-01-01

    In previous work we reported on the simulation of mixing behavior of a slowly rotating drum for solid-state fermentation (SSF) using a discrete particle model. In this investigation the discrete particle model is extended with heat and moisture transfer. Heat transfer is implemented in the model via

  19. Density Functional Calculations of Solid State Heats of Formation

    Politzer, Peter

    1999-01-01

    It is now feasible to compute quite accurate gas phase heats of formation for relatively small molecules by means of ab initio or density functional techniques and one of several possible approaches...

  20. Modelling of coupled heat and electric field distribution during ohmic heating of solid foods with varying sizes

    Feyissa, Aberham Hailu; Bøknæs, Niels; Nielsen, P.L.

    factors leading to variations and uncertainties in prediction of the right process parameters. The current work is focused on modelling of OH of solid food pieces of varying sizes cooked in one batch. A 3D mathematical model of coupled heat transfer and electric field during OH of shrimps has been...

  1. Quark confinement

    Joos, H.

    1976-07-01

    The main topics of these lectures are: phenomenological approach to quark confinement, standard Lagrangian of hadrondynamics, Lagrangian field theory and quark confinement, classical soliton solutions in a simple model, quantization of extended systems, colour charge screening and quantization on a lattice and remarks on applications. A survey of the scientific publications listed according to the topics until 26 March 1976 is supplemented. (BJ) [de

  2. Analysis of the vertical penetration of a heated fluid layer in a solid, miscible bed

    Eck, G.

    1982-03-01

    The present study investigates the mass and heat transfer for the vertical penetration of a heated fluid layer in a solid, miscible bed using water-salt solutions (ZnBr 2 , NaBr) and polyethylenglycol 1500 (PEG) as simulation materials. The time depending spatial distribution of the molten material (PEG) has been measured for the first time with conductivity probes. The dependence of the downward heat flux on the density ratio rho*, i.e. the density of the fluid / the density of the molten solid, has been investigated with two different methods of heating, planar heating with a heat exchanger in a defined initial distance to the PEG-surface and electrolytical volume heating with a defined and timely constant power input. For 1 2 two layers have been observed in the fluid. This phenomenon is caused among other things by an anomality of the mixture density of the system salt solution-PEG. This process affects the downward heat flux so strongly, that it is impossible to transfer the results of such a system in this region of rho* to another system, for example to a corecatcher. The discrepancies between the measured heat fluxes and heat transfer coefficients of this study and that of other authors can be explained by the different construction of the planar heater, or by different boundary conditions in the case of volume heating. (orig.) [de

  3. Heat and mass transfer involving droplets containing soluble solids

    Oscarson, J.L.; Briggs, D.E.

    1977-01-01

    The mass loss and temperature history of aqueous drops containing dissolved solids were measured under varying conditions of air velocity and temperature. The data taken from these drops were compared with the computer solution to a diffusional model. Very good agreement was obtained

  4. Solid-State Additive Manufacturing for Heat Exchangers

    Norfolk, Mark; Johnson, Hilary

    2015-03-01

    Energy densities in devices are increasing across many industries including power generation, high power electronics, manufacturing, and automotive. Increasingly, there is a need for very high efficiency thermal management devices that can pull heat out of a small area at higher and higher rates. Metal additive manufacturing (AM) technologies have the promise of creating parts with complex internal geometries required for integral thermal management. However, this goal has not been met due to constraints in fusion-based metal 3D printers. This work presents a new strategy for metal AM of heat exchangers using an ultrasonic sheet lamination approach.

  5. High energy bursts from a solid state laser operated in the heat capacity limited regime

    Albrecht, G.; George, E.V.; Krupke, W.F.; Sooy, W.; Sutton, S.B.

    1996-06-11

    High energy bursts are produced from a solid state laser operated in a heat capacity limited regime. Instead of cooling the laser, the active medium is thermally well isolated. As a result, the active medium will heat up until it reaches some maximum acceptable temperature. The waste heat is stored in the active medium itself. Therefore, the amount of energy the laser can put out during operation is proportional to its mass, the heat capacity of the active medium, and the temperature difference over which it is being operated. The high energy burst capacity of a heat capacity operated solid state laser, together with the absence of a heavy, power consuming steady state cooling system for the active medium, will make a variety of applications possible. Alternately, cooling takes place during a separate sequence when the laser is not operating. Industrial applications include new material working processes. 5 figs.

  6. Fluid Flow and Heat Transfer in Cellular Solids

    Ettrich, Jörg

    2014-01-01

    To determine the characteristics and properties of cellular solids for an application, and to allow a systematic practical use by means of correlations and modelling approaches, we perform experimental investigations and develop numerical methods. In view of coupled multi-physics simulations, we employ the phase-field method. Finally, the applicability is demonstrated exemplarily for open-cell metal foams, providing qualitative and quantitative comparison with experimental data.

  7. Gas-solid heat exchange in a fibrous metallic material measured by a heat regenerator technique

    Golombok, M.; Jariwala, H.; Shirvill, C.

    1990-01-01

    The convective heat transfer properties of a porous metallic fibre material used in gas surface combustion burners are studied. The important parameter governing the heat transfer between hot gas and metal fibre—the heat transfer coefficient—is measured using a non-steady-state method based on

  8. Heat Transfer to a Thin Solid Combustible in Flame Spreading at Microgravity

    Bhattacharjee, S.; Altenkirch, R. A.; Olson, S. L.; Sotos, R. G.

    1991-01-01

    The heat transfer rate to a thin solid combustible from an attached diffusion flame, spreading across the surface of the combustible in a quiescent, microgravity environment, was determined from measurements made in the drop tower facility at NASA-Lewis Research Center. With first-order Arrhenius pyrolysis kinetics, the solid-phase mass and energy equations along with the measured spread rate and surface temperature profiles were used to calculate the net heat flux to the surface. Results of the measurements are compared to the numerical solution of the complete set of coupled differential equations that describes the temperature, species, and velocity fields in the gas and solid phases. The theory and experiment agree on the major qualitative features of the heat transfer. Some fundamental differences are attributed to the neglect of radiation in the theoretical model.

  9. Airflow Obstruction and Use of Solid Fuels for Cooking or Heating: BOLD Results.

    Amaral, André F S; Patel, Jaymini; Kato, Bernet S; Obaseki, Daniel O; Lawin, Hervé; Tan, Wan C; Juvekar, Sanjay K; Harrabi, Imed; Studnicka, Michael; Wouters, Emiel F M; Loh, Li-Cher; Bateman, Eric D; Mortimer, Kevin; Buist, A Sonia; Burney, Peter G J

    2017-09-12

    Evidence supporting the association of COPD or airflow obstruction with use of solid fuels is conflicting and inconsistent. To assess the association of airflow obstruction with self-reported use of solid fuels for cooking or heating. We analysed 18,554 adults from the BOLD study, who had provided acceptable post-bronchodilator spirometry measurements and information on use of solid fuels. The association of airflow obstruction with use of solid fuels for cooking or heating was assessed by sex, within each site, using regression analysis. Estimates were stratified by national income and meta-analysed. We carried out similar analyses for spirometric restriction, chronic cough and chronic phlegm. We found no association between airflow obstruction and use of solid fuels for cooking or heating (ORmen=1.20, 95%CI 0.94-1.53; ORwomen=0.88, 95%CI 0.67-1.15). This was true for low/middle and high income sites. Among never smokers there was also no evidence of an association of airflow obstruction with use of solid fuels (ORmen=1.00, 95%CI 0.57-1.76; ORwomen=1.00, 95%CI 0.76-1.32). Overall, we found no association of spirometric restriction, chronic cough or chronic phlegm with the use of solid fuels. However, we found that chronic phlegm was more likely to be reported among female never smokers and those who had been exposed for ≥20 years. Airflow obstruction assessed from post-bronchodilator spirometry was not associated with use of solid fuels for cooking or heating.

  10. Heat supply from municipal solid waste incineration plants in Japan: Current situation and future challenges.

    Tabata, Tomohiro; Tsai, Peii

    2016-02-01

    The use of waste-to-energy technology as part of a municipal solid waste management strategy could reduce the use of fossil fuels and contribute to prevention of global warming. In this study, we examined current heat and electricity production by incineration plants in Japan for external use. Herein, we discuss specific challenges to the promotion of heat utilisation and future municipal solid waste management strategies. We conducted a questionnaire survey to determine the actual conditions of heat production by incineration plants. From the survey results, information of about 498 incineration plants was extracted. When we investigated the relationship between heat production for external use and population density where incineration plants were located, we found that regions with a population density situation. © The Author(s) 2015.

  11. Robust Modelling of Heat and Mass Transfer in Processing of Solid Foods

    Feyissa, Aberham Hailu

    The study is focused on combined heat and mass transfer during processing of solid foods such as baking and frying processes. Modelling of heat and mass transfer during baking and frying is a significant scientific challenge. During baking and frying, the food undergoes several changes...... in microstructure and other physical properties of the food matrix. The heat and water transport inside the food is coupled in a complex way, which for some food systems it is not yet fully understood. A typical example of the latter is roasting of meat in convection oven, where the mechanism of water transport...... is unclear. Establishing the robust mathematical models describing the main mechanisms reliably is of great concern. A quantitative description of the heat and mass transfer during the solid food processing, in the form of mathematical equations, implementation of the solution techniques, and the value...

  12. Repetitive 1 Hz fast-heating fusion driver HAMA pumped by diode pumped solid state laser

    Mori, Yoshitaka; Sekine, Takashi; Komeda, Osamu

    2014-01-01

    We describe a repetitive fast-heating fusion driver called HAMA pumped by Diode Pumped Solid State Laser (DPSSL) to realize the counter irradiation of sequential implosion and heating laser beams. HAMA was designed to activate DPSSL for inertial confinement fusion (ICF) research and to realize a unified ICF machine for power plants. The details of a four-beam alignment scheme and the results of the counter irradiation of stainless plates are shown. (author)

  13. On Heat Transfer through a Solid Slab Heated Uniformly and Periodically: Determination of Thermal Properties

    Rojas-Trigos, J. B.; Bermejo-Arenas, J. A.; Marin, E.

    2012-01-01

    In this paper, some heat transfer characteristics through a sample that is uniformly heated on one of its surfaces by a power density modulated by a periodical square wave are discussed. The solution of this problem has two contributions, comprising a transient term and an oscillatory term, superposed to it. The analytical solution is compared to…

  14. Molecular dynamics study of solid-liquid heat transfer and passive liquid flow

    Yesudasan Daisy, Sumith

    High heat flux removal is a challenging problem in boilers, electronics cooling, concentrated photovoltaic and other power conversion devices. Heat transfer by phase change is one of the most efficient mechanisms for removing heat from a solid surface. Futuristic electronic devices are expected to generate more than 1000 W/cm2 of heat. Despite the advancements in microscale and nanoscale manufacturing, the maximum passive heat flux removal has been 300 W/cm2 in pool boiling. Such limitations can be overcome by developing nanoscale thin-film evaporation based devices, which however require a better understanding of surface interactions and liquid vapor phase change process. Evaporation based passive flow is an inspiration from the transpiration process that happens in trees. If we can mimic this process and develop heat removal devices, then we can develop efficient cooling devices. The existing passive flow based cooling devices still needs improvement to meet the future demands. To improve the efficiency and capacity of these devices, we need to explore and quantify the passive flow happening at nanoscales. Experimental techniques have not advanced enough to study these fundamental phenomena at the nanoscale, an alternative method is to perform theoretical study at nanoscales. Molecular dynamics (MD) simulation is a widely accepted powerful tool for studying a range of fundamental and engineering problems. MD simulations can be utilized to study the passive flow mechanism and heat transfer due to it. To study passive flow using MD, apart from the conventional methods available in MD, we need to have methods to simulate the heat transfer between solid and liquid, local pressure, surface tension, density, temperature calculation methods, realistic boundary conditions, etc. Heat transfer between solid and fluids has been a challenging area in MD simulations, and has only been minimally explored (especially for a practical fluid like water). Conventionally, an

  15. Residential home heating: The potential for air source heat pump technologies as an alternative to solid and liquid fuels

    Kelly, J. Andrew; Fu, Miao; Clinch, J. Peter

    2016-01-01

    International commitments on greenhouse gases, renewables and air quality warrant consideration of alternative residential heating technologies. The residential sector in Ireland accounts for approximately 25% of primary energy demand with roughly half of primary home heating fuelled by oil and 11% by solid fuels. Displacing oil and solid fuel usage with air source heat pump (ASHP) technology could offer household cost savings, reductions in emissions, and reduced health impacts. An economic analysis estimates that 60% of homes using oil, have the potential to deliver savings in the region of €600 per annum when considering both running and annualised capital costs. Scenario analysis estimates that a grant of €2400 could increase the potential market uptake of oil users by up to 17% points, whilst a higher oil price, similar to 2013, could further increase uptake from heating oil users by 24% points. Under a combined oil-price and grant scenario, CO_2 emissions reduce by over 4 million tonnes per annum and residential PM_2_._5 and NO_X emissions from oil and peat reduce close to zero. Corresponding health and environmental benefits are estimated in the region of €100m per annum. Sensitivity analyses are presented assessing the impact of alternate discount rates and technology performance. This research confirms the potential for ASHP technology and identifies and informs policy design considerations with regard to oil price trends, access to capital, targeting of grants, and addressing transactions costs. - Highlights: • Air Source Heat Pumps can offer substantial savings over oil fired central heating. • Significant residential air and climate emission reductions are possible. • Associated health and environmental benefits are estimated up to €100m per annum. • Results can inform policy interventions in the residential market to support change.

  16. Finite element procedures for coupled linear analysis of heat transfer, fluid and solid mechanics

    Sutjahjo, Edhi; Chamis, Christos C.

    1993-01-01

    Coupled finite element formulations for fluid mechanics, heat transfer, and solid mechanics are derived from the conservation laws for energy, mass, and momentum. To model the physics of interactions among the participating disciplines, the linearized equations are coupled by combining domain and boundary coupling procedures. Iterative numerical solution strategy is presented to solve the equations, with the partitioning of temporal discretization implemented.

  17. T5 heat treatment of semi-solid metal processed aluminium alloy F357

    Moller, H

    2009-04-01

    Full Text Available The T5 heat treatment of semi-solid metal (SSM) processed alloy F357 was investigated by considering the effects of cooling rate and natural aging after casting, as well as artificial aging parameters on tensile properties. In addition, the tensile...

  18. Improvements in or relating to transfer of heat to fluidized-solid beds

    1952-01-30

    A method is described for supplying heat to a dense turbulent mass of finely divided solids fluidized by an upwardly flowing gas to resemble a boiling liquid having a well-defined upper level, which comprises contacting the mass with the surface of a heat-transfer element heated by a fluid combustion mixture burning in contact with the surface, the surface separating the mass from the mixture, wherein the burning of the combustion mixture is localized in the heat-transfer element near the point of entry of the combustion mixture. A substantial temperature gradient is maintained along the path of the combustion mixture and combustion products through the heat-transfer element.

  19. Heat transfer in solids using infrared photothermal radiometry and simulation by Com sol multi physics

    Suarez, V.; Hernandez W, J.; Calderon, A.; Rojas T, J. B.; Juarez, A. G.; Marin, E.; Castaneda, A.

    2012-10-01

    We investigate the heat transfer through a homogeneous and isotropic solid exited by periodic light beam on its front surface. For this, we use the infrared photothermal radiometry in order to obtain the evolution of the temperature difference on the rear surface of the silicon sample as a function of the exposure time. Also, we solved the heat conduction equation for this problem with the boundary conditions congruent with the physical situation, by means of application the Com sol multi physics software and the heat transfer module. Our results show a good agree between the experimental and simulated results, which demonstrate the utility of this methodology in the study of the thermal response in solids. (Author)

  20. Thermal characterization of indirectly heated axi-symmetric solid cathode electron beam gun for melting application

    Prakash, B.; Gupta, S.; Malik, P.; Mishra, K.K.; Jha, M.N.; Kandaswamy, E.; Martin, M.

    2015-01-01

    Electron beam melting gun with indirectly heated axi-symmetric solid cathode was designed, fabricated and characterized experimentally. The thermal simulation and optical analysis of the electron gun was carried out to estimate the power required to achieve the emission temperature of the solid cathode, to obtain the temperature distribution in the assembly and the beam transportation. On the basis of the thermal simulation and electron optics, the electron gun design was finalised. The electron gun assembly was fabricated and installed in the vacuum chamber for carrying out the experiment to find the actual temperature distribution. Thermocouple and two colour pyrometer were used to measure the temperature at various locations in the electron gun. The attenuation effect of the viewing port glass of the vacuum chamber was compensated in the final reading of the temperature measured by the pyrometer. The temperature of solid cathode obtained by the experiment was found to be 2800K which is the emission temperature of solid cathode. (author)

  1. Solid and liquid Equation of state for initially porous aluminum where specific heat is constant

    Forbes, Jerry W.; Lemar, E. R.; Brown, Mary

    2011-06-01

    A porous solid's initial state is off the thermodynamic surface of the non-porous solid to start with but when pressure is high enough to cause total pore collapse or crush up, then the final states are on the condensed matter thermodynamic surfaces. The Hugoniot for the fully compacted solid is above the Principle Hugoniot with pressure, temperature and internal energy increased at a given v. There are a number of ways to define this hotter Hugoniot, which can be referenced to other thermodynamic paths on this thermodynamic surface. The choice here was to use the Vinet isotherm to define a consistent thermodynamic surface for the solid and melt phase of 6061 aluminum where specific heat is constant for the P-v-T space of interest. Analytical equations are developed for PH and TH.

  2. On heat transfer through a solid slab heated uniformly and periodically: determination of thermal properties

    Rojas-Trigos, J B; Bermejo-Arenas, J A; Marín, E

    2012-01-01

    In this paper, some heat transfer characteristics through a sample that is uniformly heated on one of its surfaces by a power density modulated by a periodical square wave are discussed. The solution of this problem has two contributions, comprising a transient term and an oscillatory term, superposed to it. The analytical solution is compared to the experimental results obtained by using the approach first proposed by Ångström, which has become a well-known thermal wave experimental procedure used for the determination of thermal diffusivity. A number of conclusions are drawn from this comparison, which highlight the need to carefully consider the experimental setup employed when carrying out this type of measurement. The results may be of interest to those dealing with heat transfer problems, thermal characterization techniques and/or involved in the teaching of partial differential equations at undergraduate or graduate level. (paper)

  3. Ukrainian brown-coal tars recovered at low-temperature carbonization with solid heating medium

    Kuznetsov, V I; Govorova, R P; Fadeicheva, A G; Kigel, T B; Chernykh, M K

    1955-01-01

    Three samples of tar were recovered in the laboratory from brown coals carbonized at 375/sup 0/ to 456/sup 0/ +- 25/sup 0/ in a retort with inner heating by solid circulating medium, namely, semicoke (ratio: 4 or 3:1) first heated to 700/sup 0/. One comparative (parallel) experiment was carried out in a retort with inner heating by inert gases entering the retort at 580/sup 0/ to 600/sup 0/ and leaving it at 115/sup 0/ to 120/sup 0/. The tars that were recovered from the retort with the solid heating medium contained a high percentage of coal dust and moisture, which were separated from the tars in supercentrifuges (15,000 rpm). Four samples of cleaned tars were fractionated in a Cu flask with a 2-ball fractional column. The tars from the retort with the solid-heating medium are characterized by increased yield of the petroleum-ether fraction (16.3 or 19.3%) and decreased yield of the paraffin fraction (15.1 to 21.2%) in comparison with those of tar from the retort with gas heating (5.9% of the petroleum ether fraction and 36.5% of paraffin fraction). The yield of paraffin from the paraffin fraction also decreased from 90.6% to 62.6-74.3%. This result shows that in the first case the carbonized products were cracked to a higher degree than those from the retort with gas heating. In raw phenols recovered from fractions of investigated tars, the yield of the phenol-cresol fraction (182/sup 0/ to 204/sup 0/) decreased from 25.9% to 13.0-18.9%.

  4. CFD simulation of a dry scroll vacuum pump with clearances, solid heating and thermal deformation

    Spille-Kohoff, A.; Hesse, J.; Andres, R.; Hetze, F.

    2017-08-01

    Although dry scroll vacuum pumps (DSPV) are essential devices in many different industrial processes, the CFD simulation of such pumps is not widely used and often restricted to simplified cases due to its complexity: The working principle with a fixed and an orbiting scroll leads to working chambers that are changing in time and are connected through moving small radial and axial clearances in the range of 10 to 100 μm. Due to the low densities and low mass flow rates in vacuum pumps, it is important to include heat transfer towards and inside the solid components. Solid heating is very slow compared to the scroll revolution speed and the gas behaviour, thus a special workflow is necessary to reach the working conditions in reasonable simulation times. The resulting solid temperature is then used to compute the thermal deformation, which usually results in gap size changes that influence leakage flows. In this paper, setup steps and results for the simulation of a DSVP are shown and compared to theoretical and experimental results. The time-varying working chambers are meshed with TwinMesh, a hexahedral meshing programme for positive displacement machines. The CFD simulation with ANSYS CFX accounts for gas flow with compressibility and turbulence effects, conjugate heat transfer between gas and solids, and leakage flows through the clearances. Time-resolved results for torques, chamber pressure, mass flow, and heat flow between gas and solids are shown, as well as time- and space-resolved results for pressure, velocity, and temperature for different operating conditions of the DSVP.

  5. Element composition of solid airborne particles deposited in snow in the vicinity of gas-fired heating plant

    Talovskaya, Anna Valerievna; Yazikov, Yegor (Egor) Grigoryevich; Filimonenko, Ekaterina Anatolievna; Samokhina, Nataljya Pavlovna; Shakhova, Tatiana Sergeevna; Parygina, Irina Alekseevna

    2016-01-01

    Local heating plants are the main pollution source of rural areas. Currently, there are few studies on the composition of local heating plants emissions. The article deals with the research results of air pollution level with solid airborne particles in the vicinity of local gas-fired heating plants of some districts of Tomsk region. The snow sampling was conducted for the purpose of solid airborne particles extraction from snow cover. The content of 28 chemical elements (heavy metals, rare e...

  6. Heavy quarks

    Khoze, V.A.

    1983-10-01

    We discuss the results accumulated during the last five years in heavy quark physics and try to draw a simple general picture of the present situation. The survey is based on a unified point of view resulting from quantum chromodynamics. (orig.)

  7. Nonlinear thermal interaction between a heat-generating particulate bed and a solid

    Cheung, F.B.; Stein, R.P.; Epstein, M.; Gabor, J.D.; Bingle, J.D.

    1980-01-01

    The process of combined conduction and radiation in a large, heat-generating, dry particulate bed in sudden contact with a semi-infinite solid is studied analytically by a successive approximation method and numerically by a finite difference method. The transient behavior of the system, in particular, the behavior of the temperature at the particulate bed-solid interface, is obtained as a function of two dimensionless controlling parameters. Also obtained are the conditions leading to incipient melting of the system. Based upon the finite difference solution, the present approximate method, which is shown to be rather simple and convenient to use, is found to yield rapidly converging and sufficiently accurate results

  8. High Temperature Gas-to-Gas Heat Exchanger Based on a Solid Intermediate Medium

    R. Amirante

    2014-04-01

    Full Text Available This paper proposes the design of an innovative high temperature gas-to-gas heat exchanger based on solid particles as intermediate medium, with application in medium and large scale externally fired combined power plants fed by alternative and dirty fuels, such as biomass and coal. An optimization procedure, performed by means of a genetic algorithm combined with computational fluid dynamics (CFD analysis, is employed for the design of the heat exchanger: the goal is the minimization of its size for an assigned heat exchanger efficiency. Two cases, corresponding to efficiencies equal to 80% and 90%, are considered. The scientific and technical difficulties for the realization of the heat exchanger are also faced up; in particular, this work focuses on the development both of a pressurization device, which is needed to move the solid particles within the heat exchanger, and of a pneumatic conveyor, which is required to deliver back the particles from the bottom to the top of the plant in order to realize a continuous operation mode. An analytical approach and a thorough experimental campaign are proposed to analyze the proposed systems and to evaluate the associated energy losses.

  9. An improved heat transfer configuration for a solid-core nuclear thermal rocket engine

    Clark, J.S.; Walton, J.T.; Mcguire, M.L.

    1992-07-01

    Interrupted flow, impingement cooling, and axial power distribution are employed to enhance the heat-transfer configuration of a solid-core nuclear thermal rocket engine. Impingement cooling is introduced to increase the local heat-transfer coefficients between the reactor material and the coolants. Increased fuel loading is used at the inlet end of the reactor to enhance heat-transfer capability where the temperature differences are the greatest. A thermal-hydraulics computer program for an unfueled NERVA reactor core is employed to analyze the proposed configuration with attention given to uniform fuel loading, number of channels through the impingement wafers, fuel-element length, mass-flow rate, and wafer gap. The impingement wafer concept (IWC) is shown to have heat-transfer characteristics that are better than those of the NERVA-derived reactor at 2500 K. The IWC concept is argued to be an effective heat-transfer configuration for solid-core nuclear thermal rocket engines. 11 refs

  10. A finite volume procedure for fluid flow, heat transfer and solid-body stress analysis

    Jagad, P. I.

    2018-04-12

    A unified cell-centered unstructured mesh finite volume procedure is presented for fluid flow, heat transfer and solid-body stress analysis. An in-house procedure (A. W. Date, Solution of Transport Equations on Unstructured Meshes with Cell-Centered Colocated Variables. Part I: Discretization, International Journal of Heat and Mass Transfer, vol. 48 (6), 1117-1127, 2005) is extended to include the solid-body stress analysis. The transport terms for a cell-face are evaluated in a structured grid-like manner. The Cartesian gradients at the center of each cell-face are evaluated using the coordinate transformation relations. The accuracy of the procedure is demonstrated by solving several benchmark problems involving different boundary conditions, source terms, and types of loading.

  11. Cellular interface morphologies in directional solidification. III - The effects of heat transfer and solid diffusivity

    Ungar, Lyle H.; Bennett, Mark J.; Brown, Robert A.

    1985-01-01

    The shape and stability of two-dimensional finite-amplitude cellular interfaces arising during directional solidification are compared for several solidification models that account differently for latent heat released at the interface, unequal thermal conductivities of melt and solid, and solute diffusivity in the solid. Finite-element analysis and computer-implemented perturbation methods are used to analyze the families of steadily growing cellular forms that evolve from the planar state. In all models a secondary bifurcation between different families of finite-amplitude cells exists that halves the spatial wavelength of the stable interface. The quantitative location of this transition is very dependent on the details of the model. Large amounts of solute diffusion in the solid retard the growth of large-amplitude cells.

  12. Solid particle effects on heat transfer in a multi-layered molten pool with gas injection

    Bilbao y Leon, Rosa Marina; Corradini, Michael L.

    2006-01-01

    In the very unlikely event of a severe reactor accident involving core melt and pressure vessel failure, it is important to identify the circumstances that would allow the molten core material to cool down and resolidify, bringing core debris to a stable coolable state. To achieve this, it has been proposed to flood the cavity with water from above forming a layered structure where upward heat loss from the molten pool to the water will cause the core material to quench and solidify. In this situation the molten pool would become a three-phase mixture: e.g., a solid and liquid slurry formed by the molten pool as it cools to a temperature below the temperature of liquidus, agitated by the gases formed in the concrete ablation process. The present work quantifies the partition of the heat losses upward and downward in this multi-layered configuration, considering the influence of the viscosity and the solid fraction in the pool, from test data obtained from intermediate scale experiments at the University of Wisconsin-Madison. These experimental results show heat transfer behavior for multi-layered pools for a range of viscosities and solid fractions. These results are compared to previous experimental studies and well known correlations and models

  13. Theoretical analysis for the specific heat and thermal parameters of solid C60

    Soto, J. R.; Calles, A.; Castro, J. J.

    1997-08-01

    We present the results of a theoretical analysis for the thermal parameters and phonon contribution to the specific heat in solid C60. The phonon contribution to the specific heat is calculated through the solution of the corresponding dynamical matrix, for different points in the Brillouin zone, and the construccion of the partial and generalized phonon density of states. The force constants are obtained from a first principle calculation, using a SCF Hartree-Fock wave function from the Gaussian 92 program. The thermal parameters reported are the effective temperatures and vibrational amplitudes as a function of temperature. Using this model we present a parametization scheme in order to reproduce the general behaviour of the experimental specific heat for these materials.

  14. A coupled theory for chemically active and deformable solids with mass diffusion and heat conduction

    Zhang, Xiaolong; Zhong, Zheng

    2017-10-01

    To analyse the frequently encountered thermo-chemo-mechanical problems in chemically active material applications, we develop a thermodynamically-consistent continuum theory of coupled deformation, mass diffusion, heat conduction and chemical reaction. Basic balance equations of force, mass and energy are presented at first, and then fully coupled constitutive laws interpreting multi-field interactions and evolving equations governing irreversible fluxes are constructed according to the energy dissipation inequality and the chemical kinetics. To consider the essential distinction between mass diffusion and chemical reactions in affecting free energy and dissipations of a highly coupled system, we regard both the concentrations of diffusive species and the extent of reaction as independent state variables. This new formulation then distinguishes between the energy contribution from the diffusive species entering the solid and that from the subsequent chemical reactions occurring among these species and the host solid, which not only interact with stresses or strains in different manners and on different time scales, but also induce different variations of solid microstructures and material properties. Taking advantage of this new description, we further establish a specialized isothermal model to predict precisely the transient chemo-mechanical response of a swelling solid with a proposed volumetric constraint that accounts for material incompressibility. Coupled kinetics is incorporated to capture the volumetric swelling of the solid caused by imbibition of external species and the simultaneous dilation arised from chemical reactions between the diffusing species and the solid. The model is then exemplified with two numerical examples of transient swelling accompanied by chemical reaction. Various ratios of characteristic times of diffusion and chemical reaction are taken into account to shed light on the dependency on kinetic time scales of evolution patterns for

  15. Influence of inlet velocity of air and solid particle feed rate on holdup mass and heat transfer characteristics in cyclone heat exchanger

    Mothilal, T.; Pitchandi, K.

    2015-01-01

    Present work elaborates the effect of inlet velocity of air and solid particle feed rate on holdup mass and heat transfer characteristics in a cyclone heat exchanger. The RNG k-ε turbulence model was adopted for modeling high turbulence flow and Discrete phase model (DPM) to track solid particles in a cyclone heat exchanger by ANSYS FLUENT software. The effect of inlet air velocity (5 to 25 m/s) and inlet solid particle feed rate of (0.2 to 2.5 g/s) at different particle diameter (300 to 500 μm) on holdup mass and heat transfer rate in cyclone heat exchanger was studied at air inlet temperature of 473 K. Results show that holdup mass and heat transfer rate increase with increase in inlet air velocity and inlet solid particle feed rate. Influence of solid particle feed rate on holdup mass has more significance. Experimental setup was built for high efficiency cyclone. Good agreement was found between experimental and simulation pressure drop. Empirical correlation was derived for dimensionless holdup mass and Nusselt number based on CFD data by regression technique. Correlation predicts dimensional holdup mass with +5% to -8% errors of experimental data and Nusselt number with +9% to -3%

  16. Influence of inlet velocity of air and solid particle feed rate on holdup mass and heat transfer characteristics in cyclone heat exchanger

    Mothilal, T. [T. J. S. Engineering College, Gummidipoond (India); Pitchandi, K. [Sri Venkateswara College of Engineering, Sriperumbudur (India)

    2015-10-15

    Present work elaborates the effect of inlet velocity of air and solid particle feed rate on holdup mass and heat transfer characteristics in a cyclone heat exchanger. The RNG k-ε turbulence model was adopted for modeling high turbulence flow and Discrete phase model (DPM) to track solid particles in a cyclone heat exchanger by ANSYS FLUENT software. The effect of inlet air velocity (5 to 25 m/s) and inlet solid particle feed rate of (0.2 to 2.5 g/s) at different particle diameter (300 to 500 μm) on holdup mass and heat transfer rate in cyclone heat exchanger was studied at air inlet temperature of 473 K. Results show that holdup mass and heat transfer rate increase with increase in inlet air velocity and inlet solid particle feed rate. Influence of solid particle feed rate on holdup mass has more significance. Experimental setup was built for high efficiency cyclone. Good agreement was found between experimental and simulation pressure drop. Empirical correlation was derived for dimensionless holdup mass and Nusselt number based on CFD data by regression technique. Correlation predicts dimensional holdup mass with +5% to -8% errors of experimental data and Nusselt number with +9% to -3%.

  17. Mathematical model of solid food pasteurization by ohmic heating: influence of process parameters.

    Marra, Francesco

    2014-01-01

    Pasteurization of a solid food undergoing ohmic heating has been analysed by means of a mathematical model, involving the simultaneous solution of Laplace's equation, which describes the distribution of electrical potential within a food, the heat transfer equation, using a source term involving the displacement of electrical potential, the kinetics of inactivation of microorganisms likely to be contaminating the product. In the model, thermophysical and electrical properties as function of temperature are used. Previous works have shown the occurrence of heat loss from food products to the external environment during ohmic heating. The current model predicts that, when temperature gradients are established in the proximity of the outer ohmic cell surface, more cold areas are present at junctions of electrodes with lateral sample surface. For these reasons, colder external shells are the critical areas to be monitored, instead of internal points (typically geometrical center) as in classical pure conductive heat transfer. Analysis is carried out in order to understand the influence of pasteurisation process parameters on this temperature distribution. A successful model helps to improve understanding of these processing phenomenon, which in turn will help to reduce the magnitude of the temperature differential within the product and ultimately provide a more uniformly pasteurized product.

  18. Experimental heat capacity of solid hydrogen as a function of molar volume

    Krause, J.K.

    1978-01-01

    Constant volume heat capacity measurements have been made on six solid hydrogen samples with low orthohydrogen concentrations. The measurements extend from approximately 1.5 K to the melting line, with molar volumes ranging from 22.787 cm 3 /mole to 16.193 cm 3 /mole. Although clustering of the ortho molecules was observed, the low temperature heat capacity anomaly due to the orthohydrogen pairs could be described quite well by the assumption of a fixed distribution. The data were corrected to obtain a lattice heat capacity which on extrapolation to T = 0 yielded Debye temperatures and a volume dependent Grueneisen parameter. A modified Mie-Grueneisen approximation was used to define a volume and temperature dependent Grueneisen parameter which was used to calculate the equation of state, P(V,T), and isothermal bulk modulus, B/sub T/(V,T), for the six isochores. An extrapolation of the equation of state to T = 0 and P = 0 by two different methods yields a molar volume which, when compared with other determinations, gives a recommended value of 23.20 +- 0.05 cm 3 /mole. A rapid increase in the conversion rate of orthohydrogen to parahydrogen was observed at approximately theta/sub o/12. The molar volumes along the melting curve also have been determined directly for the first time in this volume range. These results have been used to show that a low temperature Lindemann melting relation is only approximately valid for solid hydrogen to 50 K

  19. q-deformed Einstein's model to describe specific heat of solid

    Guha, Atanu; Das, Prasanta Kumar

    2018-04-01

    Realistic phenomena can be described more appropriately using generalized canonical ensemble, with proper parameter sets involved. We have generalized the Einstein's theory for specific heat of solid in Tsallis statistics, where the temperature fluctuation is introduced into the theory via the fluctuation parameter q. At low temperature the Einstein's curve of the specific heat in the nonextensive Tsallis scenario exactly lies on the experimental data points. Consequently this q-modified Einstein's curve is found to be overlapping with the one predicted by Debye. Considering only the temperature fluctuation effect(even without considering more than one mode of vibration is being triggered) we found that the CV vs T curve is as good as obtained by considering the different modes of vibration as suggested by Debye. Generalizing the Einstein's theory in Tsallis statistics we found that a unique value of the Einstein temperature θE along with a temperature dependent deformation parameter q(T) , can well describe the phenomena of specific heat of solid i.e. the theory is equivalent to Debye's theory with a temperature dependent θD.

  20. Quark matter and quark stars at finite temperature in Nambu-Jona-Lasinio model

    Chu, Peng-Cheng; Wang, Bin; Dong, Yu-Min; Jia, Yu-Yue; Wang, Shu-Mei; Ma, Hong-Yang [Qingdao Technological University, School of Science, Qingdao (China); Li, Xiao-Hua [University of South China, School of Nuclear Science and Technology, Hengyang (China); University of South China, Cooperative Innovation Center for Nuclear Fuel Cycle Technology and Equipment, Hengyang (China)

    2017-08-15

    We extend the SU(3) Nambu-Jona-Lasinio (NJL) model to include two types of vector interaction. Using these two types of vector interaction in NJL model, we study the quark symmetry free energy in asymmetric quark matter, the constituent quark mass, the quark fraction, the equation of state (EOS) for β-equilibrium quark matter, the maximum mass of QSs at finite temperature, the maximum mass of proto-quark stars (PQSs) along the star evolution, and the effects of the vector interaction on the QCD phase diagram. We find that comparing zero temperature case, the values of quark matter symmetry free energy get larger with temperature increasing, which will reduce the difference between the fraction of u, d and s quarks and stiffen the EoS for β-equilibrium quark matter. In particular, our results indicate that the maximum masses of the quark stars increase with temperature because of the effects of the quark matter symmetry free energy, and we find that the heating(cooling) process for PQSs will increase (decrease) the maximum mass within NJL model. (orig.)

  1. Quark bags

    Kerman, A.K.

    1981-01-01

    This short talk gives some very general comments on what I see as the impact on nuclear physics of the last ten years' developments in the picture of the nucleon and the hadron. On the other hand there may also be some nuclear physics lessons - lessons we've learned by trying to deal with the multi-fermion system over a long period - and I will discuss what those lessons might be for the problem at hand, hadron phy-physics up to 31 GeV. After that I will discuss a number of implications of quarks for low energy physics

  2. Confinement of quarks

    Nambu, J.

    1978-01-01

    Three quark models of hadron structure, which suggest an explanation of quarks confinement mechanism in hadrons are considered. Quark classifications, quark flawors and colours, symmetry model of hadron structure based on the colour theory of strong interaction are discussed. Diagrams of colour combinations of quarks and antiquarks, exchange of gluons, binding quarks in hadron. Quark confinement models based on the field theory, string model rotating and bag model are discussed. Diagrams of the colour charge distribution explaining the phenomena of infrared ''slavery'' and ultraviolet ''freedom'' are given. The models considered explain but some quark properties, creating prerequisites for the development of the consequent theory of hadron structure

  3. Quark mass effects in quark number susceptibilities

    Graf, Thorben; Petreczky, Peter

    2017-01-01

    The quark degrees of freedom of the QGP with special focus on mass effects are investigated. A next-to-leading-order perturbation theory approach with quark mass dependence is applied and compared to lattice QCD results. (paper)

  4. Heat Transfer Analysis and Modification of Thermal Probe for Gas-Solid Measurement

    Hong Zhang

    2016-01-01

    Full Text Available The presented work aims to measure the gas-solid two-phase mass flow-rate in pneumatic conveyor, and a novel modified thermal probe is applied. A new analysis of the local heat transfer coefficients of thermal probe is presented, while traditional investigations focus on global coefficients. Thermal simulations are performed in Fluent 6.2 and temperature distributions of the probe are presented. The results indicate that the probe has obviously stable and unstable heat transfer areas. Based on understanding of probe characteristics, a modified probe structure is designed, which makes the probe output signal more stable and widens the measuring range. The experiments are carried out in a special designed laboratory scale pneumatic conveyor, and the modified probe shows an unambiguous improvement of the performance compared with the traditional one.

  5. Heat Melt Compaction as an Effective Treatment for Eliminating Microorganisms from Solid Waste

    Hummerick, Mary P.; Strayer, Richard F.; McCoy, Lashelle E.; Richards, Jeffrey T.; Ruby, Anna Maria; Wheeler, Ray; Fisher, John

    2013-01-01

    One of the technologies being tested at NASA Ames Research Center (ARC) for the Advance Exploration Systems program and as part of the logistics and repurposing project is heat melt compaction (HMC) of solid waste. Reduces volume, removes water and renders a biologically stable and safe product. The HMC compacts and reduces the trash volume as much as 90o/o greater than the current manual compaction used by the crew.The project has three primary goals or tasks. 1. Microbiological analysis of HMC hardware surfaces before and after operation. 2. Microbiological and physical characterizations of heat melt tiles made from trash at different processing times and temperatures. 3. Long term storage and stability of HMC trash tiles or "Do the bugs grow back?"

  6. Transport phenomena in solid oxide fuel cell electrodes focusing on heat transfer related to chemical reactions

    Navasa, M; Andersson, M; Yuan, J; Sundén, B

    2012-01-01

    Solid oxide fuel cells (SOFCs) are widely studied for their advantages especially at high temperatures. However, operating at high temperatures represents a high cost due to the strict requirements the materials are expected to fulfill. Thus, the main goal in SOFC research has been to decrease the operating temperature so that the range of available materials is widened and hence, the operating cost can be reduced. In this paper, the different heat sources that contribute to the cell energy balance are presented with strong emphasis on the chemical reactions that take place in SOFCs. The knowledge of which heat sources or sinks taking place and their locations within the SOFC can provide useful information for further design and efficiency improvements.

  7. Radiometric probe design for the measurement of heat flux within a solid rocket motor nozzle

    Goldey, Charles L.; Laughlin, William T.; Popper, Leslie A.

    1996-11-01

    Improvements to solid rocket motor (SRM) nozzle designs and material performance is based on the ability to instrument motors during test firings to understand the internal combustion processes and the response of nozzle components to the severe heating environment. Measuring the desired parameters is very difficult because the environment inside of an SRM is extremely severe. Instrumentation can be quickly destroyed if exposed to the internal rocket motor environment. An optical method is under development to quantify the heating of the internal nozzle surface. A radiometric probe designed for measuring the thermal response and material surface recession within a nozzle while simultaneously confining the combustion products has been devised and demonstrated. As part of the probe design, optical fibers lead to calibrated detectors that measure the interior nozzle thermal response. This two color radiometric measurement can be used for a direct determination of the total heat flux impinging on interior nozzle surfaces. This measurement has been demonstrated using a high power CO2 laser to simulate SRM nozzle heating conditions on carbon phenolic and graphite phenolic materials.

  8. Dynamic modeling and evaluation of solid oxide fuel cell - combined heat and power system operating strategies

    Nanaeda, Kimihiro; Mueller, Fabian; Brouwer, Jacob; Samuelsen, Scott

    Operating strategies of solid oxide fuel cell (SOFC) combined heat and power (CHP) systems are developed and evaluated from a utility, and end-user perspective using a fully integrated SOFC-CHP system dynamic model that resolves the physical states, thermal integration and overall efficiency of the system. The model can be modified for any SOFC-CHP system, but the present analysis is applied to a hotel in southern California based on measured electric and heating loads. Analysis indicates that combined heat and power systems can be operated to benefit both the end-users and the utility, providing more efficient electric generation as well as grid ancillary services, namely dispatchable urban power. Design and operating strategies considered in the paper include optimal sizing of the fuel cell, thermal energy storage to dispatch heat, and operating the fuel cell to provide flexible grid power. Analysis results indicate that with a 13.1% average increase in price-of-electricity (POE), the system can provide the grid with a 50% operating range of dispatchable urban power at an overall thermal efficiency of 80%. This grid-support operating mode increases the operational flexibility of the SOFC-CHP system, which may make the technology an important utility asset for accommodating the increased penetration of intermittent renewable power.

  9. Invert 1.0: A program for solving the nonlinear inverse heat conduction problem for one-dimensional solids

    Snider, D.M.

    1981-02-01

    INVERT 1.0 is a digital computer program written in FORTRAN IV which calculates the surface heat flux of a one-dimensional solid using an interior-measured temperature and a physical description of the solid. By using two interior-measured temperatures, INVERT 1.0 can provide a solution for the heat flux at two surfaces, the heat flux at a boundary and the time dependent power, or the heat flux at a boundary and the time varying thermal conductivity of a material composing the solid. The analytical solution to inversion problem is described for the one-dimensional cylinder, sphere, or rectangular slab. The program structure, input instructions, and sample problems demonstrating the accuracy of the solution technique are included

  10. Two-Quark Condensate Changes with Quark Current Mass

    Lu Changfang; Lue Xiaofu; Wu Xiaohua; Zhan Yongxin

    2009-01-01

    Using the Schwinger-Dyson equation and perturbation theory, we calculate the two-quark condensates for the light quarks u, d, strange quark s and a heavy quark c with their current masses respectively. The results show that the two-quark condensate will decrease when the quark mass increases, which hints the chiral symmetry may be restored for the heavy quarks.

  11. Development of thermoelectric power generation system utilizing heat of combustible solid waste

    Kajikawa, T.; Ito, M.; Katsube, I.; Shibuya, E.

    1994-01-01

    The paper presents the development of thermoelectric power generation system utilizing heat of municipal solid waste. The systematic classification and design guideline are proposed in consideration of the characteristics of solid waste processing system. The conceptual design of thermoelectric power generation system is carried out for a typical middle scale incinerator system (200 ton/day) by the local model. Totally the recovered electricity is 926.5 kWe by 445 units (569,600 couples). In order to achieve detailed design, one dimensional steady state model taking account of temperature dependency of the heat transfer performance and thermoelectric properties is developed. Moreover, small scale on-site experiment on 60 W class module installed in the real incinerator is carried out to extract various levels of technological problems. In parallel with the system development, high temperature thermoelectric elements such as Mn-Si and so on are developed aiming the optimization of ternary compound and high performance due to controlled fine-grain boundary effect. The manganese silicide made by shrinking-rate controlled sintering method performs 5 (μW/cm K2) in power factor at 800 K. copyright 1995 American Institute of Physics

  12. Thermal-Flow Code for Modeling Gas Dynamics and Heat Transfer in Space Shuttle Solid Rocket Motor Joints

    Wang, Qunzhen; Mathias, Edward C.; Heman, Joe R.; Smith, Cory W.

    2000-01-01

    A new, thermal-flow simulation code, called SFLOW. has been developed to model the gas dynamics, heat transfer, as well as O-ring and flow path erosion inside the space shuttle solid rocket motor joints by combining SINDA/Glo, a commercial thermal analyzer. and SHARPO, a general-purpose CFD code developed at Thiokol Propulsion. SHARP was modified so that friction, heat transfer, mass addition, as well as minor losses in one-dimensional flow can be taken into account. The pressure, temperature and velocity of the combustion gas in the leak paths are calculated in SHARP by solving the time-dependent Navier-Stokes equations while the heat conduction in the solid is modeled by SINDA/G. The two codes are coupled by the heat flux at the solid-gas interface. A few test cases are presented and the results from SFLOW agree very well with the exact solutions or experimental data. These cases include Fanno flow where friction is important, Rayleigh flow where heat transfer between gas and solid is important, flow with mass addition due to the erosion of the solid wall, a transient volume venting process, as well as some transient one-dimensional flows with analytical solutions. In addition, SFLOW is applied to model the RSRM nozzle joint 4 subscale hot-flow tests and the predicted pressures, temperatures (both gas and solid), and O-ring erosions agree well with the experimental data. It was also found that the heat transfer between gas and solid has a major effect on the pressures and temperatures of the fill bottles in the RSRM nozzle joint 4 configuration No. 8 test.

  13. Structural transformation in mechanosynthesized bcc Fe-Al-Si(Ge) solid solutions during heating

    Kubalova, L.M.; Sviridov, I.A.; Vasilyeva, O.Ya.; Fadeeva, V.I.

    2007-01-01

    X-ray diffractometry and Moessbauer spectroscopy study of Fe 50 Al 25 Si 25 and Fe 50 Al 25 Ge 25 alloys obtained by mechanical alloying (MA) of elementary powders was carried out. Phase transformation during heating of synthesized products was studied using differential scanning calorimetry (DSC). After 2.5 h of MA monophase alloys containing bcc Fe(Al, Ge) solid solutions Fe(Al, Si) are formed. Fe(Al, Si) is partially ordered B2 type and Fe(Al, Ge) is completely disordered. DSC curves of synthesized alloys displayed the presence of exothermal peaks caused by phase transformation. The metastable Fe(Al, Si) solid solution transformed into FeAl 1-x Si x (B2) and FeSi 1-x Al x (B20) equilibrium phases. The Fe(Al, Ge) solid solution transformed into equilibrium phases through intermediate stage of Fe 6 Ge 3 Al 2 metastable phase formation. The Fe 6 Ge 3 Al 2 phase dissociated into three equilibrium phases: FeAl 1-x Ge x (B2), χ-Fe 6 Ge 5 and η-Fe 13 (Ge, Al) 8 (B8 2 ). The structure of Fe 6 Ge 3 Al 2 was calculated by Rietveld method, the distribution of Al and Ge in the elementary cell and its parameters were calculated. Moessbauer study showed that Fe(Al, Si) and Fe(Al, Ge) solid solutions are paramagnetic. In the equilibrium state the alloy containing Si is also paramagnetic while the alloy with Ge showed ferromagnetic properties

  14. Effects of Time, Heat, and Oxygen on K Basin Sludge Agglomeration, Strength, and Solids Volume

    Delegard, Calvin H.; Sinkov, Sergey I.; Schmidt, Andrew J.; Daniel, Richard C.; Burns, Carolyn A.

    2011-01-04

    Sludge disposition will be managed in two phases under the K Basin Sludge Treatment Project. The first phase is to retrieve the sludge that currently resides in engineered containers in the K West (KW) Basin pool at ~10 to 18°C. The second phase is to retrieve the sludge from interim storage in the sludge transport and storage containers (STSCs) and treat and package it in preparation for eventual shipment to the Waste Isolation Pilot Plant. The work described in this report was conducted to gain insight into how sludge may change during long-term containerized storage in the STSCs. To accelerate potential physical and chemical changes, the tests were performed at temperatures and oxygen partial pressures significantly greater than those expected in the T Plant canyon cells where the STSCs will be stored. Tests were conducted to determine the effects of 50°C oxygenated water exposure on settled quiescent uraninite (UO2) slurry and a full simulant of KW containerized sludge to determine the effects of oxygen and heat on the composition and mechanical properties of sludge. Shear-strength measurements by vane rheometry also were conducted for UO2 slurry, mixtures of UO2 and metaschoepite (UO3•2H2O), and for simulated KW containerized sludge. The results from these tests and related previous tests are compared to determine whether the settled solids in the K Basin sludge materials change in volume because of oxidation of UO2 by dissolved atmospheric oxygen to form metaschoepite. The test results also are compared to determine if heating or other factors alter sludge volumes and to determine the effects of sludge composition and settling times on sludge shear strength. It has been estimated that the sludge volume will increase with time because of a uranium metal → uraninite → metaschoepite oxidation sequence. This increase could increase the number of containers required for storage and increase overall costs of sludge management activities. However, the volume

  15. Effects of Time, Heat, and Oxygen on K Basin Sludge Agglomeration, Strength, and Solids Volume

    Delegard, Calvin H.; Sinkov, Sergey I.; Schmidt, Andrew J.; Daniel, Richard C.; Burns, Carolyn A.

    2011-01-01

    Sludge disposition will be managed in two phases under the K Basin Sludge Treatment Project. The first phase is to retrieve the sludge that currently resides in engineered containers in the K West (KW) Basin pool at ∼10 to 18 C. The second phase is to retrieve the sludge from interim storage in the sludge transport and storage containers (STSCs) and treat and package it in preparation for eventual shipment to the Waste Isolation Pilot Plant. The work described in this report was conducted to gain insight into how sludge may change during long-term containerized storage in the STSCs. To accelerate potential physical and chemical changes, the tests were performed at temperatures and oxygen partial pressures significantly greater than those expected in the T Plant canyon cells where the STSCs will be stored. Tests were conducted to determine the effects of 50 C oxygenated water exposure on settled quiescent uraninite (UO 2 ) slurry and a full simulant of KW containerized sludge to determine the effects of oxygen and heat on the composition and mechanical properties of sludge. Shear-strength measurements by vane rheometry also were conducted for UO 2 slurry, mixtures of UO2 and metaschoepite (UO 3 · 2H 2 O), and for simulated KW containerized sludge. The results from these tests and related previous tests are compared to determine whether the settled solids in the K Basin sludge materials change in volume because of oxidation of UO2 by dissolved atmospheric oxygen to form metaschoepite. The test results also are compared to determine if heating or other factors alter sludge volumes and to determine the effects of sludge composition and settling times on sludge shear strength. It has been estimated that the sludge volume will increase with time because of a uranium metal → uraninite → metaschoepite oxidation sequence. This increase could increase the number of containers required for storage and increase overall costs of sludge management activities. However, the

  16. Application of cascading thermoelectric generator and cooler for waste heat recovery from solid oxide fuel cells

    Zhang, Houcheng; Kong, Wei; Dong, Feifei; Xu, Haoran; Chen, Bin; Ni, Meng

    2017-01-01

    Highlights: • Cascading thermoelectric devices are proposed to recover waste heat from SOFCs. • A theoretical model is developed to analyze the new hybrid system performance. • Performance parameters for evaluating the hybrid system are specified. • Feasibility and effectiveness of the proposed system are demonstrated. • Effects of some important parameters on the system performance are discussed. - Abstract: Besides electricity generation, solid oxide fuel cells (SOFCs) produce a significant amount of waste heat, which needs to be immediately removed to ensure the normal operation of SOFCs. If the waste heat is recovered through bottoming thermal devices, the global efficiency of SOFCs can be improved. In this study, a new hybrid system mainly consisting of a thermoelectric generator, a thermoelectric cooler and an SOFC is proposed to recover the waste heat from SOFC for performance enhancement. The thermodynamic and electrochemical irreversible losses in each component are fully considered. An analytical relationship between the SOFC operating current density and the thermoelectric devices dimensionless electric current is derived, from which the range of SOFC operating current density that permits the thermoelectric devices to effectively work is determined. The equivalent power output and efficiency for the hybrid system are specified under different operating current density regions. The feasibility and effectiveness are illustrated by comparing the proposed hybrid system with the stand-alone SOFC. It is found that the power density and efficiency of the proposed system allow 2.3% and 4.6% larger than that of the stand-alone SOFC, respectively. Finally, various parametric analyses are performed to discuss the effects of some design and operation parameters on the hybrid system performance.

  17. Fully coupled heat conduction and deformation analyses of visco-elastic solids

    Khan, Kamran

    2012-04-21

    Visco-elastic materials are known for their capability of dissipating energy. This energy is converted into heat and thus changes the temperature of the materials. In addition to the dissipation effect, an external thermal stimulus can also alter the temperature in a viscoelastic body. The rate of stress relaxation (or the rate of creep) and the mechanical and physical properties of visco-elastic materials, such as polymers, vary with temperature. This study aims at understanding the effect of coupling between the thermal and mechanical response that is attributed to the dissipation of energy, heat conduction, and temperature-dependent material parameters on the overall response of visco-elastic solids. The non-linearly viscoelastic constitutive model proposed by Schapery (Further development of a thermodynamic constitutive theory: stress formulation, 1969,Mech. Time-Depend. Mater. 1:209-240, 1997) is used and modified to incorporate temperature- and stress-dependent material properties. This study also formulates a non-linear energy equation along with a dissipation function based on the Gibbs potential of Schapery (Mech. Time-Depend. Mater. 1:209-240, 1997). A numerical algorithm is formulated for analyzing a fully coupled thermo-visco-elastic response and implemented it in a general finite-element (FE) code. The non-linear stress- and temperature-dependent material parameters are found to have significant effects on the coupled thermo-visco-elastic response of polymers considered in this study. In order to obtain a realistic temperature field within the polymer visco-elastic bodies undergoing a non-uniform heat generation, the role of heat conduction cannot be ignored. © Springer Science+Business Media, B. V. 2012.

  18. Heat Melt Compaction as an Effective Treatment for Eliminating Microorganisms from Solid Waste

    Hummerick, Mary P.; Strayer, Richard F.; McCoy, Lashelle E.; Richards, Jeffrey T.; Ruby, Anna Maria; Wheeler, Ray; Fisher, John

    2013-01-01

    One of the technologies being tested at Ames Research Center as part of the logistics and repurposing project is heat melt compaction (HMC) of solid waste to reduce volume, remove water and render a biologically stable and safe product. Studies at Kennedy Space Center have focused on the efficacy of the heat melt compaction process for killing microorganisms in waste and specific compacter operation protocols, i.e., time and temperature required to achieve a sterile, stable product. The work. reported here includes a controlled study to examine the survival and potential re-growth of specific microorganisms over a 6-month period of storage after heating and compaction. Before heating and compaction, ersatz solid wastes were inoculated with Bacillus amyloliquefaciens and Rhodotorula mucilaginosa, previously isolated from recovered space shuttle mission food and packaging waste. Compacted HMC tiles were sampled for microbiological analysis at time points between 0 and 180 days of storage in a controlled environment chamber. In addition, biological indicator strips containing spores of Bacillus atrophaeus and Geobacillus stearothermophilus were imbedded in trash to assess the efficacy of the HMC process to achieve sterilization. Analysis of several tiles compacted at 180deg C for times of 40 minutes to over 2 hours detected organisms in all tile samples with the exception of one exposed to 180deg C for approximately 2 hours. Neither of the inoculated organisms was recovered, and the biological indicator strips were negative for growth in all tiles indicating at least local sterilization of tile areas. The findings suggest that minimum time/temperature combination is required for complete sterilization. Microbial analysis of tiles processed at lower temperatures from 130deg C-150deg C at varying times will be discussed, as well as analysis of the bacteria and fungi present on the compactor hardware as a result of exposure to the waste and the surrounding environment

  19. Accelerated testing of solid oxide fuel cell stacks for micro combined heat and power application

    Hagen, Anke; Høgh, Jens Valdemar Thorvald; Barfod, Rasmus

    2015-01-01

    State-of-the-art (SoA) solid oxide fuel cell (SOFC) stacks are tested using profiles relevant for use in micro combined heat and power (CHP) units. Such applications are characterised by dynamic load profiles. In order to shorten the needed testing time and to investigate potential acceleration...... of degradation, the profiles are executed faster than required for real applications. Operation with fast load cycling, both using hydrogen and methane/steam as fuels, does not accelerate degradation compared to constant operation, which demonstrates the maturity of SoA stacks and enables transferring knowledge...... effect for long life-times than regular short time changes of operation. In order to address lifetime testing it is suggested to build a testing program consisting of defined modules that represent different application profiles, such as one module at constant conditions, followed by modules at one set...

  20. Modeling the burnout of solid polydisperse fuel under the conditions of external heat transfer

    Skorik, I. A.; Goldobin, Yu. M.; Tolmachev, E. M.; Gal'perin, L. G.

    2013-11-01

    A self-similar burnout mode of solid polydisperse fuel is considered taking into consideration heat transfer between fuel particles, gases, and combustion chamber walls. A polydisperse composition of fuel is taken into account by introducing particle distribution functions by radiuses obtained for the kinetic and diffusion combustion modes. Equations for calculating the temperatures of particles and gases are presented, which are written for particles average with respect to their distribution functions by radiuses taking into account the fuel burnout ratio. The proposed equations take into consideration the influence of fuel composition, air excess factor, and gas recirculation ratio. Calculated graphs depicting the variation of particle and gas temperatures, and the fuel burnout ratio are presented for an anthracite-fired boiler.

  1. Formation of Ni(Al, Mo) solid solutions by mechanical alloying and their ordering on heating

    Portnoj, V.K.; Tomilin, I.A.; Blinov, A.M.; Kulik, T.

    2002-01-01

    The Ni(Al, Mo) solid solutions with different crystalline lattice periods (0.3592 and 0.3570 nm correspondingly) are formed in the course of the Ni 70 Al 25 Mo 5 and Ni 75 Al 20 Mo 5 powder mixtures mechanical alloying (MA) (through the mechanical activation in a vibrating mill). After MA the Mo atoms in the Ni 75 Al 20 Mo 5 mixture completely replace the aluminium positions with formation of the Ni 75 (AlMo) 25 (the L1 2 -type) ternary ordered phase, whereby such a distribution remains after heating up to 700 deg C. The Ni(Al, Mo) metastable solution is formed by MA in the Ni 75 Al 20 Mo 5 mixture, which decays with the release of molybdenum and the remained aluminide undergoes ordering by the L1 2 -type [ru

  2. Quark confinement in a constituent quark model

    Langfeld, K.; Rho, M.

    1995-01-01

    On the level of an effective quark theory, we define confinement by the absence of quark anti-quark thresholds in correlation function. We then propose a confining Nambu-Jona-Lasinio-type model. The confinement is implemented in analogy to Anderson localization in condensed matter systems. We study the model's phase structure as well as its behavior under extreme conditions, i.e. high temperature and/or high density

  3. Heat impact caused molecular level changes in solid and dissolved soil organic matter

    Hofmann, Diana; Steffen, Bernhard; Eckhardt, Kai-Uwe; Leinweber, Peter

    2015-04-01

    The ubiquitous abundance of pyrolysed, highly aromatic organic matter, called "Black Carbon" (BC), in all environmental compartments became increasingly important in different fields of research beyond intensive investigated atmospheric aerosol due to climatic relevance. Its predominant high resistance to abiotic and biotic degradation resulted in turnover times from less than a century to several millennia. This recalcitrance led to the enrichment of BC in soils, accounting for 1-6% (European forest soils) to 60% (Chernozems) of total soil organic matter (SOM). Hence, soil BC acts an important sink in the global carbon cycle. In contrast, consequences for the nitrogen cycle up to date are rather inconsistently discussed. Soil related dissolved organic matter (DOM) is a major controlling factor in soil formation, an important pathway of organic matter transport and one of the largest active carbon reservoirs on earth, if considering oceans and other bodies of water. The aim of this study was to evaluate the effects of artificially simulated wildfire by thermal treatment on the molecular composition of water extractable soil organic matter (DOM). Soils from two outdoor lysimeters with different management history were investigated. Soil samples, non-heated and heated up to 350°C were analyzed for elemental composition (carbon, nitrogen and sulfur) and for bulk molecular composition by Pyrolysis-Field Ionization Mass Spectrometry (Py-FIMS) and synchrotron-based X-ray Absorption Near-Edge Spectroscopy (XANES) at the C- and N K-edges. DOM-samples obtained by hot water extraction, desalting and concentration by solid phase extraction were subsequently analyzed by flow injection analysis in a Fourier Transform Ion Cyclotron Resonance Mass Spectrometer (FTICR-MS), equipped with an ESI source and a 7 T supra-conducting magnet (LTQ-FT Ultra, ThermoFisher Scientific). This technique is the key technique for the analysis of complex samples due to its outstanding mass

  4. A Microstructural Evaluation of Friction Stir Welded 7075 Aluminum Rolled Plate Heat Treated to the Semi-Solid State

    Ava Azadi Chegeni

    2018-01-01

    Full Text Available Two rolled plates of 7075 aluminum alloy were used as starting material. The plates were welded using a simultaneous double-sided friction stir welding (FSW process. One way of obtaining feedstock materials for Semi-solid processing or thixoforming is via deformation routes followed by partial melting in the semi-solid state. As both the base plate materials and the friction weld area have undergone extensive deformation specimens were subjected to a post welding heat-treatment in the semi-solid range at a temperature of 628 °C, for 3 min in order to observe the induced microstructural changes. A comparison between the microstructural evolution and mechanical properties of friction stir welded plates was performed before and after the heat-treatment in the Base Metal (BM, the Heat Affected Zone (HAZ, the Thermomechanically Affected Zone (TMAZ and the Nugget Zone (NZ using optical microscopy, Scanning Electron microscopy (SEM and Vickers hardness tests. The results revealed that an extremely fine-grained structure, obtained in the NZ after FSW, resulted in a rise of hardness from the BM to the NZ. Furthermore, post welding heat-treatment in the semi-solid state gave rise to a consistent morphology throughout the material which was similar to microstructures obtained by the thixoforming process. Moreover, a drop of hardness was observed after heat treatment in all regions as compared to that in the welded microstructure.

  5. Army Solid State Laser Program: Design, Operation, and Mission Analysis for a Heat-Capacity Laser

    Dane, C B; Flath, L; Rotter, M; Fochs, S; Brase, J; Bretney, K

    2001-01-01

    Solid-state lasers have held great promise for the generation of high-average-power, high-quality output beams for a number of decades. However, the inherent difficulty of scaling the active solid-state gain media while continuing to provide efficient cooling has limited demonstrated powers to 10X the diffraction limit. Challenges posed by optical distortions and depolarization arising from internal temperature gradients in the gain medium of a continuously cooled system are only increased for laser designs that would attempt to deliver the high average power in the form of high energy pulses (>25J) from a single coherent optical aperture. Although demonstrated phase-locking of multiple laser apertures may hold significant promise for the future scaling of solid-state laser systems,1 the continuing need for additional technical development and innovation coupled with the anticipated complexity of these systems effectively limits this approach for near-term multi-kW laser operation outside of a laboratory setting. We have developed and demonstrated a new operational mode for solid-state laser systems in which the cooling of the gain medium is separated in time from the lasing cycle. In ''heat-capacity'' operation, no cooling takes place during lasing. The gain medium is pumped very uniformly and the waste heat from the excitation process is stored in the solid-state gain medium. By depositing the heat on time scales that are short compared to thermal diffusion across the optical aperture, very high average power operation is possible while maintaining low optical distortions. After a lasing cycle, aggressive cooling can then take place in the absence of lasing, limited only by the fracture limit of the solid-state medium. This mode of operation is ideally suited for applications that require 1-30s engagements at very high average power. If necessary, multiple laser apertures can provide continuous operation. Land Combat mission analysis of a stressing air defense

  6. Numerical estimation of phase transformations in solid state during Yb:YAG laser heating of steel sheets

    Kubiak, Marcin, E-mail: kubiak@imipkm.pcz.pl; Piekarska, Wiesława; Domański, Tomasz; Saternus, Zbigniew [Institute of Mechanics and Machine Design Foundations, Częstochowa University of Technology, Dąbrowskiego 73, 42-200 Częstochowa (Poland); Stano, Sebastian [Welding Technologies Department, Welding Institute, Błogosławionego Czesława 16-18, 44-100 Gliwice (Poland)

    2015-03-10

    This work concerns the numerical modeling of heat transfer and phase transformations in solid state occurring during the Yb:YAG laser beam heating process. The temperature field is obtained by the numerical solution into transient heat transfer equation with convective term. The laser beam heat source model is developed using the Kriging interpolation method with experimental measurements of Yb:YAG laser beam profile taken into account. Phase transformations are calculated on the basis of Johnson - Mehl - Avrami (JMA) and Koistinen - Marburger (KM) kinetics models as well as continuous heating transformation (CHT) and continuous cooling transformation (CCT) diagrams for S355 steel. On the basis of developed numerical algorithms 3D computer simulations are performed in order to predict temperature history and phase transformations in Yb:YAG laser heating process.

  7. Recycling of hazardous solid waste material using high-temperature solar process heat

    Schaffner, B.; Meier, A.; Wuillemin, D.; Hoffelner, W.; Steinfeld, A.

    2003-03-01

    A novel high-temperature solar chemical reactor is proposed for the thermal recycling of hazardous solid waste material using concentrated solar power. A 10 kW solar reactor prototype was designed and tested for the carbothermic reduction of electric arc furnace dusts (EAFD). The reactor was subjected to mean solar flux intensities of 2000 kW/m2 and operated in both batch and continuous mode within the temperature range 1120-1400 K. Extraction of up to 99% and 90% of the Zn originally contained in the EAFD was achieved in the residue for the batch and continuous solar experiments, respectively. The condensed off-gas products consisted mainly of Zn, Pb, and Cl. No ZnO was detected when the O{sub 2} concentration remained below 2 vol.-%. The use of concentrated solar energy as the source of process heat offers the possibility of converting hazardous solid waste material into valuable commodities for processes in closed and sustainable material cycles. (author)

  8. Quarks and mesons in nuclei

    Rho, M.

    1981-01-01

    Quantum chromodynamics is believed to be candidate theory for the strong interactions and contains as its ingredients spinor quark fields and vector gluons, none of which can perhaps be ever liberated and detected in laboratories. A nucleus consists of nucleons bound by nuclear force which are however separately observable and which seem to preserve their identities even under extreme conditions. An intriguing question is: when compressed to high densities or heated to high temperature, at what point does a nuclear matter cease to be describable in terms of nucleon and meson degrees of freedom, but become a plasma of quarks and gluons; and how does this transition occur. This is not an idle question. If quarks and gluons are never to be observed isolated, then it may be that at low energies (or at low densities) they are not the right variables to do physics with. Instead hadrons must be. On the other hand, asymptotic freedom - the unique property of non-abelian gauge theories to which QCD belongs that quark-gluon and gluon-gluon interactions get weaker at short distances - tells us that at some large matter density the matter must necessarily be in the form of quark gas interacting only weakly. This means that a change in degrees of freedom must take place. We would like to know where this occurs and how. In this talk, I would like to address to this question by discussing first the large success we have had in understanding the role that mesons play in finite nuclei and nuclear matter and then attempting to correlate nucleon and meson degrees of freedom to quark-gluon degrees of freedom. In my opinion we are now at a stage where we feel fairly confident in our understanding of nucleon-meson structure of nuclei and nuclear matter and any further progress in deeper understanding of nuclear dynamics - and strong interactions - must come from QCD or its effective version, bags or strings. (orig.)

  9. Mass and Heat Transfer in Ion-Exchange Membranes Applicable to Solid Polymer Fuel Cells

    Otteroey, M

    1996-04-01

    In this doctoral thesis, an improved emf method for determination of transference numbers of two counter ions in ion-exchange membranes is presented. Transference numbers were obtained as a continuous function of the composition. The method avoids problems with diffusion by using a stack of membranes. Water transference coefficients in ion-exchange membranes is discussed and reversible and irreversible water transfer is studied by emf methods. Efforts were made to get data relevant to the solid polymer fuel cell. The results support the findings of other researchers that the reversible water transfer is lower than earlier predicted. A chapter on the conductivity of ion-exchange membranes establishes a method to separate the very thin liquid layers surrounding the membranes in a stack. Using the method it was found that the conductivity is obtained with high accuracy and that the liquid layer in a membrane stack can contribute significantly to the total measured resistance. A four point impedance method was tested to measure the conductivity of membranes under fuel cell conditions. Finally, there is a discussion of reversible heat effects and heat transfer in ion-exchange membranes. 155 refs., 45 figs., 13 tabs.

  10. Study of the heat conductivity of double and triple disordered solid solutions in the titanium-zirconium-hafnium system

    Zarichnyak, Yu.P.; Lisnenko, T.A.

    1977-10-01

    Measurements are presented of the heat physical properties of trinary alloys in the system Ti-Zr-Hf. The possibility is shown of summarizing the results of the measurement and prediction of the heat conductivity of trinary continuous disordered solid solutions. Comparison of calculated results with experimental data shows that the method of modeling of the structure and prediction of heat conductivity suggested yields good qualitative and quantitative agreement throughout the entire range of change of concentration of the components. The maximum disagreement between calculated and experimental results is about 10%. 8 references, 2 figures, 1 table.

  11. Study on subcooled-forced flow boiling heat transfer and critical heat flux of solid particle-water two-phase mixture

    Koizumi, Yasuo; Mochizuki, Manabu; Ohtake, Hiroyasu

    1999-01-01

    The effect of solid particle introduction on forced flow boiling and the critical heat flux was examined for the mixture of subcooled-water and 0.6 mm glass beads. When the particles were introduced, the growth on of a superheated layer near a wall seemed to be suppressed and the onset of nucleate boiling was delayed. The particles tempted for bubbles to condense at nucleation sites, and then the initiation of net vapor generation was also delayed and sifted to a high wall-superheat region. The nucleate boiling heat transfer was augmented by the particles, which considered to be caused by the combination of the suppression of the superheated layer growth and the promotion of the condensation and dissipation of the bubbles. The wall superheat at the critical heat flux condition was sifted to a high wall superheat region and the critical heat flux itself was also elevated a little. (author)

  12. Observability of quarks

    Bjorken, J.D.

    1985-12-01

    Even if stable hadrons with fractional charge do not exist, most of the criteria of observability used for ordinary elementary particles apply in principle to quarks as well. This is especially true in a simplified world containing only hadrons made of top quarks and gluons. In the real world containing light quarks, essential complications do occur, but most of the conclusions survive

  13. CONFERENCE: Quark matter 88

    Jacob, Maurice

    1988-01-01

    The 'Quark Matter' Conference caters for physicists studying nuclear matter under extreme conditions. The hope is that relativistic (high energy) heavy ion collisions allow formation of the long-awaited quark-gluon plasma, where the inter-quark 'colour' force is no longer confined inside nucleon-like dimensions

  14. Metallurgical features of the formation of a solid-phase metal joint upon electric-circuit heating

    Latypov, R. A.; Bulychev, V. V.; Zybin, I. N.

    2017-06-01

    The thermodynamic conditions of formation of a joint between metals using the solid-phase methods of powder metallurgy, welding, and deposition of functional coatings upon electric-current heating of the surfaces to be joined are studied. Relations are obtained to quantitatively estimate the critical sizes of the circular and linear active centers that result in the formation of stable bonding zones.

  15. Graded Reflectivity Mirror for the Solid State Heat Capacity Laser Final Report CRADA No. TC-2085-04

    Yamamoto, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Davis, J. A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-09-27

    This was a collaborative effort between The Regents of the University of California, Lawrence Livermore National Laboratory (LLNL) and the Boeing Company, to develop a Graded Reflectivity Mirror (GRM) to achieve improved near field fill and higher brightness in the far field output of LLNL’s Solid State Heat Capacity Laser (SSHCL).

  16. Wall-to-bed heat transfer in gas-solid fluidized beds: a computational and experimental study

    Patil, D.J.; Smit, J.; van Sint Annaland, M.; Kuipers, J.A.M.

    2006-01-01

    The wall-to-bed heat transfer in gas-solid fluidized beds is mainly determined by phenomena prevailing in a thermal boundary layer with a thickness in the order of magnitude of the size of a single particle. In this thermal boundary layer the temperature gradients are very steep and the local

  17. 3D numerical simulation of fluid–solid coupled heat transfer with variable property in a LBE-helium heat exchanger

    Chen, Fei, E-mail: chenfei@iet.cn [Institute of Engineering Thermophysics, Chinese Academy of Sciences, 11 Beisihuanxi Road, Beijing 100190 (China); North China University of Water Resources and Electric Power, 36 Beihuan Road, Zhengzhou, Henan 450011 (China); Cai, Jun, E-mail: caijun@iet.cn [Institute of Engineering Thermophysics, Chinese Academy of Sciences, 11 Beisihuanxi Road, Beijing 100190 (China); Li, Xunfeng, E-mail: lixunfeng@iet.cn [Institute of Engineering Thermophysics, Chinese Academy of Sciences, 11 Beisihuanxi Road, Beijing 100190 (China); Huai, Xiulan, E-mail: hxl@iet.cn [Institute of Engineering Thermophysics, Chinese Academy of Sciences, 11 Beisihuanxi Road, Beijing 100190 (China); Wang, Yongwei, E-mail: wangyongwei@iet.cn [Institute of Engineering Thermophysics, Chinese Academy of Sciences, 11 Beisihuanxi Road, Beijing 100190 (China)

    2014-07-01

    Highlights: • Heat transfer in heat exchanger can be improved by increasing helium's flow rate. • The outlet temperature of helium decreases with increasing helium's flow rate. • Balance is necessary between good heat transfer and high helium outlet temperature. - Abstract: LBE-helium experimental loop of ADS (LELA) and LBE-helium heat exchanger have been designed and constructed with the supporting of the “ADS Transmutation System” project of Chinese Academy of Sciences. In order to investigate the flow and heat transfer characteristics between LBE and helium, 3D numerical simulation of fluid–solid coupled heat transfer with variable property in the LBE-helium heat exchanger is conducted in the present study. The effects of mass-flow-rates of helium and LBE in the shell-side and tube-side on the heat transfer performance are addressed. It is found that the heat transfer performance can be significantly improved by increasing helium mass-flow-rate in the shell-side. In order to easily and quickly obtain the outlet temperatures of helium and LBE, a concept of modified effectiveness is introduced and correlated as the function of tube-side to shell-side heat capacity rate ratio. The results show that the outlet temperature of helium decreases with increasing helium mass-flow-rate. Therefore, considering the utilization of high-temperature helium in the future, for example power generation, there should be a tradeoff between good heat transfer performance and high outlet helium temperature when confirming helium mass-flow-rate.

  18. Final Technical Report: Using Solid Particles as Heat Transfer Fluid for use in Concentrating Solar Power (CSP) Plants

    Lattanzi, Aaron [Univ. of Colorado, Boulder, CO (United States); Hrenya, Christine [Univ. of Colorado, Boulder, CO (United States)

    2016-03-31

    In today’s industrial economy, energy consumption has never been higher. Over the last 15 years the US alone has consumed an average of nearly 100 quadrillion BTUs per year [21]. A need for clean and renewable energy sources has become quite apparent. The SunShot Initiative is an ambitious effort taken on by the United States Department of Energy that targets the development of solar energy that is cost-competitive with other methods for generating electricity. Specifically, this work is concerned with the development of concentrating solar power plants (CSPs) with granular media as the heat transfer fluid (HTF) from the solar receiver. Unfortunately, the prediction of heat transfer in multiphase flows is not well understood. For this reason, our aim is to fundamentally advance the understanding of multiphase heat transfer, particularly in gas-solid flows, while providing quantitative input for the design of a near black body receiver (NBB) that uses solid grains (like sand) as the HTF. Over the course of this three-year project, a wide variety of contributions have been made to advance the state-of-the art description for non-radiative heat transfer in dense, gas-solid systems. Comparisons between a state-of-the-art continuum heat transfer model and discrete element method (DEM) simulations have been drawn. The results of these comparisons brought to light the limitations of the continuum model due to inherent assumptions in its derivation. A new continuum model was then developed for heat transfer at a solid boundary by rigorously accounting for the most dominant non-radiative heat transfer mechanism (particle-fluid-wall conduction). The new model is shown to be in excellent agreement with DEM data and captures the dependence of heat transfer on particle size, a dependency that previous continuum models were not capable of. DEM and the new continuum model were then employed to model heat transfer in a variety of receiver geometries. The results provided crucial

  19. Method for treatment of solid, frangible substances, in particular for their heating and drying and for gasification of fossil carbon

    1950-08-23

    A method is described for treating a solid, frangible material, characterized by mixing such solid in granular form with an evaporable liquid in sufficient quantity to form a fluid mixture, making such mixture pass as a confined current in a turbulent flux through a zone of heating in which such mixture is being heated to a temperature at least sufficient for the evaporation of substantially the whole of the liquid, thus forming a dispersion of solid particles in a current of the resulting vapor and subjecting the particles to the disintegrating action of the evaporation of the liquid from the surface of the particles and to the turbulent flux of the confined current of vapors.

  20. Numerical simulation of the induction heating of hybrid semi-finished materials into the semi-solid state

    Seyboldt, Christoph; Liewald, Mathias

    2017-10-01

    Current research activities at the Institute for Metal Forming Technology (IFU) of the University of Stuttgart are focusing on the manufacturing of hybrid components using semi-solid forming strategies. As part of the research project "Hybrid interaction during and after thixoforging of multi-material systems", which is founded by the German Research Foundation (DFG), a thixoforging process for producing hybrid components with cohesive metal-to-metal connections is developed. In this context, this paper deals with the numerical simulation of the inductive heating process of hybrid semi-finished materials, consisting of two different aluminium alloys. By reason of the skin effect that leads to inhomogeneous temperature distributions during inductive heating processes, the aluminium alloy with the higher melting point is thereby assembled in the outer side and the alloy with the lower melting point is assembled in the core of the semi-finished material. In this way, the graded heat distribution can be adapted to the used materialś flow properties that are heavily heat dependent. Without this graded heat distribution a proper forming process in the semi-solid state will not be possible. For numerically modelling the inductive heating system of the institute, a coupling of the magnetostatic and the thermal solver was realized by using Ansys Workbench. While the electromagnetic field and its associated heat production rate were solved in a frequency domain, the temperature development was solved in the time based domain. The numerical analysis showed that because of the high thermal conductivity of the aluminium, which leads to a rapid temperature equalization in the semi-finished material, the heating process has to be fast and with a high frequency for produce most heat in the outer region of the material. Finally, the obtained numerical results were validated with experimental heating tests.

  1. Co-flow anode/cathode supply heat exchanger for a solid-oxide fuel cell assembly

    Haltiner, Jr., Karl J.; Kelly, Sean M.

    2005-11-22

    In a solid-oxide fuel cell assembly, a co-flow heat exchanger is provided in the flow paths of the reformate gas and the cathode air ahead of the fuel cell stack, the reformate gas being on one side of the exchanger and the cathode air being on the other. The reformate gas is at a substantially higher temperature than is desired in the stack, and the cathode gas is substantially cooler than desired. In the co-flow heat exchanger, the temperatures of the reformate and cathode streams converge to nearly the same temperature at the outlet of the exchanger. Preferably, the heat exchanger is formed within an integrated component manifold (ICM) for a solid-oxide fuel cell assembly.

  2. Quark matter

    Csernai, L.; Kampert, K. H.

    1994-10-15

    Precisely one decade ago the GSI (Darmstadt)/LBL (Berkeley) Collaboration at the Berkeley Bevalac reported clear evidence for collective sidewards flow in high energy heavy ion collisions. This milestone observation clearly displayed the compression and heating up of nuclear matter, providing new insights into how the behaviour of nuclear matter changes under very different conditions. This year, evidence for azimuthally asymmetric transverse flow at ten times higher projectile energy (11 GeV per nucleon gold on gold collisions) was presented by the Brookhaven E877 collaboration at the recent European Research Conference on ''Physics of High Energy Heavy Ion Collisions'', held in Helsinki from 17-22 June.

  3. Computer program MCAP-TOSS calculates steady-state fluid dynamics of coolant in parallel channels and temperature distribution in surrounding heat-generating solid

    Lee, A. Y.

    1967-01-01

    Computer program calculates the steady state fluid distribution, temperature rise, and pressure drop of a coolant, the material temperature distribution of a heat generating solid, and the heat flux distributions at the fluid-solid interfaces. It performs the necessary iterations automatically within the computer, in one machine run.

  4. Hadron spectra and quarks

    Gasiorowicz, S.; Rosner, J.L.

    1982-01-01

    The quark model began as little more than a quantum-number counting device. After a brief period during which quarks only played a symmetry role, serious interest in quark dynamics developed. The marriage of the principle of local gauge invariance and quarks has been astonishingly productive. Although many questions still need to be be answered, there is little doubt that the strong, weak and electroweak interactions of matter are described by gauge theories of interactions of the quarks. This review is focussed on the successes

  5. Development of low temperature solid state joining technology of dissimilar for nuclear heat exchanger tube components

    NONE

    2010-08-15

    By conventional fusion welding process (TIG), a realization of reliable and sound joints for the nuclear heat exchanger components is very difficult, especially for the parts comprising of the dissimilar metal couples (Ti-STS, Ti-Cu alloy etc.). This is mainly attributed to the formation of brittle intermetallics (Ti{sub x}Cu{sub y}, Ti{sub x}Fe{sub y}, Ti{sub x}Ni{sub y} etc.) and wide difference in physical properties. Moreover, it usually employs very high thermal input, so making it difficult to obtain sound joints due to generations of high residual stresses and degradation of the adjacent base metals, even for similar metal combinations. In this project, the low temperature solid-state joining technology was established by developing new alloy fillers, e.g. the multi-component eutectic based alloys or amorphous alloys, and thereby lowering the joining temperature down to {approx}800 .deg. C without affecting the structural properties of base metals. Based on a low temperature joining, the interlayer engineering technology was then developed to be able to eliminate the brittleness of the joints for strong Ti-STS dissimilar joints, and the diffusion brazing technology of Ti-Ti with a superior joining strength and corrosion-resistance comparable to those of base metal were developed. By using those developed technologies, the joining procedures feasible for the heat exchanger components were finally established for the dissimilar metal joints including Ti tube sheet to super STS tube, Ti tube sheet to super STS tube sheet, and the joints of the Ti tube to Ti tube sheet

  6. Quark matter

    Csernai, L.; Kampert, K.H.

    1994-01-01

    Precisely one decade ago the GSI (Darmstadt)/LBL (Berkeley) Collaboration at the Berkeley Bevalac reported clear evidence for collective sidewards flow in high energy heavy ion collisions. This milestone observation clearly displayed the compression and heating up of nuclear matter, providing new insights into how the behaviour of nuclear matter changes under very different conditions. This year, evidence for azimuthally asymmetric transverse flow at ten times higher projectile energy (11 GeV per nucleon gold on gold collisions) was presented by the Brookhaven E877 collaboration at the recent European Research Conference on ''Physics of High Energy Heavy Ion Collisions'', held in Helsinki from 17-22 June

  7. On the Heat Transfer through a Solid Slab Heated Uniformly and Continuously on One of Its Surfaces

    Marin, E.; Lara-Bernal, A.; Calderon, A.; Delgado-Vasallo, O.

    2011-01-01

    Some peculiarities of the heat transfer through a sample that is heated by the superficial absorption of light energy under continuous uniform illumination are discussed. We explain, using a different approach to that presented in a recent article published in this journal (Salazar "et al" 2010 "Eur. J. Phys." 31 1053-9), that the front surface of…

  8. Effect of Heat Treatment on the Lithium Ion Conduction of the LiBH4–LiI Solid Solution

    Sveinbjörnsson, Dadi Þorsteinn; Mýrdal, Jón Steinar Garðarsson; Blanchard, Didier

    2013-01-01

    The LiBH4–LiI solid solution is a good Li+ conductor and a promising crystalline electrolyte for all-solid-state lithium based batteries. The focus of the present work is on the effect of heat treatment on the Li+ conduction. Solid solutions with a LiI content of 6.25–50% were synthesized by high...

  9. SOLID FUEL OF HYDROCARBON, WOOD AND AGRICULTURAL WASTE FOR LOCAL HEAT SUPPLY SYSTEMS

    B. M. Khroustalev

    2017-01-01

    Full Text Available In Belarus oil refining and oil producing industries are paid close attention. On the background of the active maintaining the level of oil processing and volume of oil extraction in our country and in the countries of the Eurasian Economic Union there is a steady formation of hydrocarbon-containing waste; therefore recycling of the latter is an urgent task to improve the competitiveness of production. The most cost-effective way of using hydrocarbon waste is the conversion of it into power resources. In this case it is possible to obtain significant power-saving and economic effect of the combined use of a hydrocarbon, wood, agricultural and other combustible waste, meanwhile improving the ecological situation at the sites of waste storage and creating a solid fuel with the necessary energy and specified physical-and-chemical properties. A comprehensive solution of a recycling problem makes it possible to use as energy resources a lot of waste that has not found application in other technologies, to produce alternative multi-component fuel which structure meets environmental and energy requirement for local heating systems. In addition, the implementation of such technology will make it possible to reduce power consumption of enterprises of various kinds that consume fuel and will also increase the share of local fuels in the energy balance of a particular region.

  10. Preliminary Analysis on Decay Heat Removal Capability of Helium Cooled Solid Breeder Test Blanket Module

    Ahn, Mu Young; Cho, Seung Yon; Kim, Duck Hoi; Lee, Eun Seok; Kim, Hyung Seok; Suh, Jae Seung; Yun, Sung Hwan; Cho, Nam Zin

    2007-01-01

    One of the main ITER goals is to test and validate design concepts of tritium breeding blankets relevant to DEMO or fusion power plants. Korea Helium-Cooled Solid Breeder (HCSB) Test Blanket Module (TBM) has been developed with overall objectives of achieving this goal. The TBM employs high pressure helium to cool down the First Wall (FW), Side Wall (SW) and Breeding Zone (BZ). Therefore, safety consideration is a part of the design process. Each ITER Party performing the TBM program is requested to reach a similar level of confidence in the TBM safety analysis. To meet ITER's request, Failure Mode and Effects Analysis (FMEA) studies have been performed on the TBM to identify the Postulated Initial Event (PIE). Although FMEA on the KO TBM has not been completed, in-vessel, in-box and ex-vessel Loss Of Coolant Accident (LOCA) are considered as enveloping cases of PIE in general. In this paper, accidental analyses for the three selected LOCA were performed to investigate the decay heat removal capability of the TBM. To simulate transient thermo-hydraulic behavior of the TBM for the selected scenarios, RELAP5/MOD3.2 code was used

  11. Space-Time Geometry of Quark and Strange Quark Matter

    2007-01-01

    We study quark and strange quark matter in the context of general relativity. For this purpose, we solve Einstein's field equations for quark and strange quark matter in spherical symmetric space-times. We analyze strange quark matter for the different equations of state (EOS) in the spherical symmetric space-times, thus we are able to obtain the space-time geometries of quark and strange quark matter. Also, we discuss die features of the obtained solutions. The obtained solutions are consistent with the results of Brookhaven Laboratory, i.e. the quark-gluon plasma has a vanishing shear (i.e. quark-gluon plasma is perfect).

  12. Experimental determination of convective heat transfer coefficients in the separated flow region of the Space Shuttle Solid Rocket Motor

    Whitesides, R. Harold; Majumdar, Alok K.; Jenkins, Susan L.; Bacchus, David L.

    1990-01-01

    A series of cold flow heat transfer tests was conducted with a 7.5-percent scale model of the Space Shuttle Rocket Motor (SRM) to measure the heat transfer coefficients in the separated flow region around the nose of the submerged nozzle. Modifications were made to an existing 7.5 percent scale model of the internal geometry of the aft end of the SRM, including the gimballed nozzle in order to accomplish the measurements. The model nozzle nose was fitted with a stainless steel shell with numerous thermocouples welded to the backside of the thin wall. A transient 'thin skin' experimental technique was used to measure the local heat transfer coefficients. The effects of Reynolds number, nozzle gimbal angle, and model location were correlated with a Stanton number versus Reynolds number correlation which may be used to determine the convective heating rates for the full scale Space Shuttle Solid Rocket Motor nozzle.

  13. Interface model conditions for a non-equilibrium heat transfer model for conjugate fluid/porous/solid domains

    Betchen, L.J.; Straatman, A.G.

    2005-01-01

    A mathematical and numerical model for the treatment of conjugate fluid flow and heat transfer problems in domains containing pure fluid, porous, and pure solid regions has been developed. The model is general and physically reasoned, and allows for local thermal non-equilibrium in the porous region. The model is developed for implementation on a simple collocated finite volume grid. Of particular novelty are the conditions implemented at the interfaces between porous regions, and those containing a pure solid or pure fluid. The model is validated by simulation of a three-dimensional porous plug problem for which experimental results are available. (author)

  14. Solid oxide fuel cell systems for residential micro-combined heat and power in the UK: Key economic drivers

    Hawkes, Adam; Leach, Matthew

    The ability of combined heat and power (CHP) to meet residential heat and power demands efficiently offers potentially significant financial and environmental advantages over centralised power generation and heat-provision through natural-gas fired boilers. A solid oxide fuel cell (SOFC) can operate at high overall efficiencies (heat and power) of 80-90%, offering an improvement over centralised generation, which is often unable to utilise waste heat. This paper applies an equivalent annual cost (EAC) minimisation model to a residential solid oxide fuel cell CHP system to determine what the driving factors are behind investment in this technology. We explore the performance of a hypothetical SOFC system—representing expectations of near to medium term technology development—under present UK market conditions. We find that households with small to average energy demands do not benefit from installation of a SOFC micro-CHP system, but larger energy demands do benefit under these conditions. However, this result is sensitive to a number of factors including stack capital cost, energy import and export prices, and plant lifetime. The results for small and average dwellings are shown to reverse under an observed change in energy import prices, an increase in electricity export price, a decrease in stack capital costs, or an improvement in stack lifetime.

  15. Taking a gamble on the top quark

    Flam, F.

    1994-01-01

    This article describes the possible discovery of the top quark at Fermilab. Evidence for its existence is now at the level of two standard deviations above background, but a solid claim for discovery will not be made until the probability is five standard deviations. That should require one more year of experimentation

  16. Exergy analysis of an integrated solid oxide fuel cell and organic Rankine cycle for cooling, heating and power production

    Al-Sulaiman, Fahad A.; Dincer, Ibrahim; Hamdullahpur, Feridun

    The study examines a novel system that combined a solid oxide fuel cell (SOFC) and an organic Rankine cycle (ORC) for cooling, heating and power production (trigeneration) through exergy analysis. The system consists of an SOFC, an ORC, a heat exchanger and a single-effect absorption chiller. The system is modeled to produce a net electricity of around 500 kW. The study reveals that there is 3-25% gain on exergy efficiency when trigeneration is used compared with the power cycle only. Also, the study shows that as the current density of the SOFC increases, the exergy efficiencies of power cycle, cooling cogeneration, heating cogeneration and trigeneration decreases. In addition, it was shown that the effect of changing the turbine inlet pressure and ORC pump inlet temperature are insignificant on the exergy efficiencies of the power cycle, cooling cogeneration, heating cogeneration and trigeneration. Also, the study reveals that the significant sources of exergy destruction are the ORC evaporator, air heat exchanger at the SOFC inlet and heating process heat exchanger.

  17. Duality and quarks

    Volkov, D.V.; Zheltukhin, A.A.; Pashnev, A.I.

    1975-01-01

    As it has shown, the study of vacuum transitions in dual models makes it possible to establish certain relations between duality, on the one hand, and the quark structure of resonances and the internal symmetries, on the other. In the case of Veneziano model the corresponding quark structure of resonances is determined by the infinity number of quarks of increasing mass. The intercents of the main trajectory and all adopted trajectories are additive with respect to squares of mass-forming quarks. The latter circumstance results in a number of important consequences: the presence of quadratic mass formulas for resonance states; the exact SU(infinity)-symmetry for the three-resonance coupling constants; the validity of Adler's self-consistency principle for external particles composed of different quarks and anti-quarks, etc

  18. Resource recovery from municipal solid waste by mechanical heat treatment: An opportunity

    Kamaruddin, Mohamad Anuar; Yusoff, Mohd Suffian; Ibrahim, Nurazim; Zawawi, Mohd Hafiz

    2017-04-01

    Municipal solid waste (MSW) stream in Malaysia consists of 50 to 60 % of food wastes. In general, food wastes are commingled in nature and very difficult to be managed in sustainable manner due to high moisture content. Consequently, by dumping food wastes together with inert wastes to the landfill as final disposal destination incurs large space area and reducing the lifespan of landfill. Therefore, certain fraction of the MSW as such; food wastes (FW) can be diverted from total disposal at the landfill that can improve landfill lifespan and environmental conservation. This study aims to determine the resource characteristics of FW extracted from USM cafeteria by means of mechanical heat treatment in the presence of autoclaving technology. Sampling of FW were conducted by collecting FW samples from disposal storage at designated area within USM campus. FW characteristics was performed prior and autoclaving process. The results have demonstrated that bones fraction was the highest followed by vegetable and rice with 39, 27 and 10%, respectively. Meanwhile, based on autoclaving technique, moisture content of the FW (fresh waste) were able to be reduced ranging from 65-85% to 59-69% (treated waste). Meanwhile, chemical characteristics of treated FW results in pH, TOC, TKN, C/N ratio, TP, and TK 5.12, 27,6%, 1.6%, 17.3%, 0.9% and 0.36%. The results revealed that autoclaving technology is a promising approach for MSW diversion that can be transformed into useful byproducts such as fertilizer, RDF and recyclable items.

  19. Heat and mass transfer analysis intermediate temperature solid oxide fuel cells (IT-SOFC)

    Timurkutluk, B.; Mat, M. M.; Kaplan, Y.

    2007-01-01

    Solid oxide fuel cells (SOFCs) have been considered as next generation energy conversion system due to their high efficiency, clean and quite operation with fuel flexibility. To date, yittria stabilized zirconia (YSZ) electrolytes have been mainly used for SOFC applications at high temperatures around 1000 degree C because of their high ionic conductivity, chemical stability and good mechanical properties. However, such a high temperature is undesirable for fuel cell operations in the viewpoint of stability. Moreover, high operation temperature necessitates high cost interconnect and seal materials. Thus, the reduction in the operation temperature of SOFCs is one of the key issues in the aspects of the cost reduction and the long term operation without degradation as well as commercialization of the SOFC systems. With the reducing temperature, not only low cost stainless steels and glass materials can be used as interconnect and sealing materials respectively but the manufacturing technology will also extend. Therefore, the design of complex geometrical SOFC component will also be possible. One way to reduce the operation temperature of SOFC is use of an alternative electrolyte material to YSZ showing acceptable properties at intermediate temperatures (600-800 degree C). As being one of IT-SOFC electrolyte materials, gadolinium doped ceria (GDC) has been taken great deals. In this study, a mathematical model for mass and heat transfer for a single cell GDC electrolyte SOFC system was developed and numerical solutions were evaluated. In order to verify the mathematical model, set of experiments were performed by taking species from four different samples randomly and five various temperature measurements. The numerical results reasonably agree with experimental data

  20. Solid state phase change materials for thermal energy storage in passive solar heated buildings

    Benson, D. K.; Christensen, C.

    1983-11-01

    A set of solid state phase change materials was evaluated for possible use in passive solar thermal energy storage systems. The most promising materials are organic solid solutions of pentaerythritol, pentaglycerine and neopentyl glycol. Solid solution mixtures of these compounds can be tailored so that they exhibit solid-to-solid phase transformations at any desired temperature within the range from less than 25 deg to 188 deg. Thermophysical properties such as thermal conductivity, density and volumetric expansion were measured. Computer simulations were used to predict the performance of various Trombe wall designs incorporating solid state phase change materials. Optimum performance was found to be sensitive to the choice of phase change temperatures and to the thermal conductivity of the phase change material. A molecular mechanism of the solid state phase transition is proposed and supported by infrared spectroscopic evidence.

  1. Heavy quark masses

    Testa, Massimo

    1990-01-01

    In the large quark mass limit, an argument which identifies the mass of the heavy-light pseudoscalar or scalar bound state with the renormalized mass of the heavy quark is given. The following equation is discussed: m(sub Q) = m(sub B), where m(sub Q) and m(sub B) are respectively the mass of the heavy quark and the mass of the pseudoscalar bound state.

  2. Quark diquark symmetry breaking

    Souza, M.M. de

    1980-01-01

    Assuming the baryons are made of quark-diquark pairs, the wave functions for the 126 allowed ground states are written. The quark creation and annihilations operators are generalized to describe the quark-diquark structure in terms of a parameter σ. Assuming that all quark-quark interactions are mediated by gluons transforming like an octet of vector mesons, the effective Hamiltonian and the baryon masses as constraint equations for the elements of the mass matrix is written. The symmetry is the SU(6) sub(quark)x SU(21) sub(diquark) broken by quark-quark interactions respectively invariant under U(6), U(2) sub(spin), U(3) and also interactions transforming like the eighth and the third components of SU(3). In the limit of no quark-diquark structure (σ = 0), the ground state masses is titted to within 1% of the experimental data, except for the Δ(1232), where the error is almost 2%. Expanding the decuplet mass equations in terms of σ and keeping terms only up to the second order, this error is reduced to 67%. (Author) [pt

  3. The Quark - A Decade Later

    Dakin, James T.

    1974-01-01

    Reviews theoretical principles underlying the quark model. Indicates that the agreement with experimental results and the understanding of the quark-quark force are two hurdles for the model to survive in the future. (CC)

  4. Heat transfer

    First page Back Continue Last page Overview Graphics. Heat transfer. Heat conduction in solid slab. Convective heat transfer. Non-linear temperature. variation due to flow. HEAT FLUX AT SURFACE. conduction/diffusion.

  5. Theoretical modelling and experimental study of air thermal conditioning process of a heat pump assisted solid desiccant cooling system

    Nie, Jinzhe; Li, Zan; Hu, Wenju

    2017-01-01

    purification aimed at improving indoor air quality and reducing building energy consumption. The heat and moisture transfer in adsorption desiccant rotor was theoretical modelled with one-dimensional partial differential equations. The theoretical model was validated with experimental measurements...... system, the energy performance of HP-SDC was more efficient mainly due to high efficient air purification capacity, reduction of cooling load and raised evaporation temperature. The energy performance of HP-SDC was sensitive to outdoor humidity ratio. Further improvements of HP-SDC energy efficiency......Taking the integrated gaseous contaminants and moisture adsorption potential of desiccant material, a new heat pump assisted solid desiccant cooling system (HP-SDC) was proposed based on the combination of desiccant rotor with heat pump. The HP-SDC was designed for dehumidification, cooling and air...

  6. Heavy-Quark Production

    Frixione, Stefano; Nason, Paolo; Ridolfi, Giovanni

    1997-01-01

    We review the present theoretical and experimental status of heavy quark production in high-energy collisions. In particular, we cover hadro- and photoproduction at fixed target experiments, at HERA and at the hadron colliders, as well as aspects of heavy quark production in e+e- collisions at the Z0 peak.

  7. Systematics of quark mass

    Frampton, P.H.; Jarlskog, C.

    1985-01-01

    It is shown that the quark mass matrices in the Standard Electroweak Model satisfy the empirical relation M = M 1 + Ψ(Λ 2 ), where M(M sp (')) refers to the mass matrix of the charge 2/3(-1/3) quarks normalized to the largest eigenvalue, m sub (t)(m sub (b)), and Λ = V sub (us) = 0.22

  8. Colourless confinement for quarks

    Anon.

    1994-01-01

    The enigma of quarks is that they are there, hidden deep inside nucleons and other strongly interacting particles, but refuse to come out. The tighter the quark bonds are stretched, the more difficult they are to break. This dogma has been accepted for some thirty years but has never been mathematically proved

  9. Quark radiation from LEP

    Cartwright, Susan

    1992-01-01

    Like any other electrically charged particles, quarks should give out electromagnetic radiation (photons) when they vibrate. One of the physics results from CERN's LEP collider is the first clear observation of this quark radiation from electron-positron collisions. At lower energies this radiation could only be inferred

  10. Quark radiation from LEP

    Cartwright, Susan

    1992-04-15

    Like any other electrically charged particles, quarks should give out electromagnetic radiation (photons) when they vibrate. One of the physics results from CERN's LEP collider is the first clear observation of this quark radiation from electron-positron collisions. At lower energies this radiation could only be inferred.

  11. Top Quark Physics

    Larios, F.

    2006-01-01

    We give an overview of the physics of the Top quark, from the experimental discovery to the studies of its properties. We review some of the work done on the Electroweak and Flavor Changing couplings associated with the Top quark in the Standard Model and beyond. We will focus on the specific contribution of phycisits working in Mexico and Mexican physicists working abroad

  12. Top quark theory

    Laenen, E.

    2012-01-01

    The theoretical aspects of a number of top quark properties such as its mass and its couplings are reviewed. Essential aspects in the theoretical description of top quark production, singly, in pairs and in association, as well as its decay related to spin and angular correlations are discussed.

  13. Heavy quarks and leptons

    Azimov, Ya.I.; Khoze, V.A.

    1979-01-01

    Experimental results which proved the reality of quarks are reviewed along with further experiments broadening the representation of quarks and leptons and providing the basis to develop the theory of elementary particles. The discovery of the J/psi particle is noted to give rise to the discovery of c-quark, the existance of which is confirmed by the discovery of charmed hadrons. The main aspects of quantum chromodynamics explaining the mechanism of strong interaction of quarks are considered along with those of the Weinberg-Salam theory proposed to describe weak and electromagnetic interactions of quarks and leptons. Experimental data testifying to the existance of heavy tausup(+-) leptons are presented. The history of discovery of γ mesons and of a new heavier b-quark is described. Perspectives for studying elementary particles are discussed. Further studies of γ mesons, discovery and investigation of charmed particles are noted to be immediate tasks along with the search for manifestation of t-quark considered to be a partner of b-quark from the viewpoint of the Weinberg-Salam model

  14. Smooth and robust solutions for Dirichlet boundary control of fluid-solid conjugate heat transfer problems

    Yan, Yan

    2015-01-01

    We study a new optimization scheme that generates smooth and robust solutions for Dirichlet velocity boundary control (DVBC) of conjugate heat transfer (CHT) processes. The solutions to the DVBC of the incompressible Navier-Stokes equations are typically nonsmooth, due to the regularity degradation of the boundary stress in the adjoint Navier-Stokes equations. This nonsmoothness is inherited by the solutions to the DVBC of CHT processes, since the CHT process couples the Navier-Stokes equations of fluid motion with the convection-diffusion equations of fluid-solid thermal interaction. Our objective in the CHT boundary control problem is to select optimally the fluid inflow profile that minimizes an objective function that involves the sum of the mismatch between the temperature distribution in the fluid system and a prescribed temperature profile and the cost of the control.Our strategy to resolve the nonsmoothness of the boundary control solution is based on two features, namely, the objective function with a regularization term on the gradient of the control profile on both the continuous and the discrete levels, and the optimization scheme with either explicit or implicit smoothing effects, such as the smoothed Steepest Descent and the Limited-memory Broyden-Fletcher-Goldfarb-Shanno (L-BFGS) methods. Our strategy to achieve the robustness of the solution process is based on combining the smoothed optimization scheme with the numerical continuation technique on the regularization parameters in the objective function. In the section of numerical studies, we present two suites of experiments. In the first one, we demonstrate the feasibility and effectiveness of our numerical schemes in recovering the boundary control profile of the standard case of a Poiseuille flow. In the second one, we illustrate the robustness of our optimization schemes via solving more challenging DVBC problems for both the channel flow and the flow past a square cylinder, which use initial

  15. Making quark matter at brook haven's new collider

    Jones, P.

    2002-01-01

    Quarks are believed to come in 6 flavours, only the lightest of which, the up and down quarks, are found in protons and neutrons. Isolated quarks have never been observed. As quarks are brought closer together, the force between them decreases dramatically, vanishing as the separation becomes very small. This suggests that quarks may become unbound if the density of quarks could be increased by squeezing a nucleus. The nucleus would have melted their constituent quarks, now free to roam the extended volume of the compressed nucleus. This situation would make a significant change in the structure of matter corresponding to a change of phase, rather like the transition from solid to liquid, but in this case from quark confined matter, to a quark gluon plasma (QGP). This new state of matter is thought to have been the natural phase of matter until 10 micro-seconds after the big-bang, and also to exist today in the core of neutron stars. Calculations show that the energy density needed to observe the phase transition is around 1 GeV/fm 3 , approximately 8 times that of normal nuclear matter. Attempts to recreate QGP have been underway at the relativistic heavy ion collider (RHIC) and at the CERN by colliding heavy-ion beams at the maximal energy possible. Between 4000 and 5000 charged particles are produced in the most violent events. The experimental challenge is to establish the existence of QGP from all this wealth of data. (A.C.)

  16. Experimental measurements of deep directional columnar heating by laser-generated relativistic electrons at near-solid density

    Koch, J.A.; Key, M.H.; Hatchett, S.P.; Lee, R.W.; Pennington, D.; Tabak, M.; Freeman, R.R.; Stephens, R.B.

    2002-01-01

    In our experiments, we irradiated solid CH targets with a 400 J, 5 ps, 3x10 19 W/cm 2 laser, and we used x-ray imaging and spectroscopic diagnostics to monitor the keV x-ray emission from thin Al or Au tracer layers buried within the targets. The experiments were designed to quantify the spatial distribution of the thermal electron temperature and density as a function of buried layer depth; these data provide insights into the behavior of relativistic electron currents which flow within the solid target and are directly and indirectly responsible for the heating. We measured ∼200-350 eV temperatures and near-solid densities at depths ranging from 5 to 100 μm beneath the target surface. Time-resolved x-ray spectra from Al tracers indicate that the tracers emit thermal x rays and cool slowly compared to the time scale of the laser pulse. Most intriguingly, we consistently observe annular x-ray images in all buried tracer-layer experiments, and these data show that the temperature distribution is columnar, with enhanced heating along the edges of the column. The ring diameters are much greater than the laser focal spot diameter and do not vary significantly with the depth of the tracer layer for depths greater than 30 μm. The local temperatures are 200-350 eV for all tracer depths. We discuss recent simulations of the evolution of electron currents deep within solid targets irradiated by ultra-high-intensity lasers, and we discuss how modeling and analytical results suggest that the annular patterns we observe may be related to locally strong growth of the Weibel instability. We also suggest avenues for future research in order to further illuminate the complex physics of relativistic electron transport and energy deposition inside ultra-high-intensity laser-irradiated solid targets

  17. Effects of the Solid Solution Heat Treatment on the Corrosion Resistance Property of SSC13 Cast Alloy

    Kim, Kuk-Jin [Hi-Sten Co., Ltd., Gimhae (Korea, Republic of); Lim, Su Gun [Gyeongsang National University, Jinju (Korea, Republic of); Pak, S. J. [Gachon BioNano Research Institute, Gachon University, Sungnam (Korea, Republic of)

    2015-04-15

    Recently, Stainless steels have been increasingly selected as the fitting or the valve materials of water pipes as the human health issue is getting higher and higher. Therefore, the connectors attached at pipes to deliver water are exposed to more severe environments than the pipes because crevice or galvanic corrosion is apt to occur at the fittings or the valves. Effects of the solid solution annealing, cooling rate after this heat treatment, and passivation on the corrosion properties of the shell mold casted SSC13 (STS304 alloy equivalent) were studied. The heating and quenching treatment more or less reduced hardness but effectively improved corrosion resistance. It was explained by the reduction of delta ferrite contents. Independent of heat treatment, the chemical passivation treatment also lowered corrosion rate but the improvement of corrosion resistance depended on temperature and time for passivation treatment indicating that the optimum conditions for passivation treatment were the bath temperature of 34 .deg. C and operating time of 10 minutes. Therefore it is suggested that the corrosion resistance of SSC13 can be effectively improved with the heat treatment, where SSC13 is heated for 10 minutes at 1120 °C and quenched and passivation treatment, where SSC13 is passivated for at least 10 seconds at 34 °C nitric acid solution.

  18. Heat Modeling and Material Development of Mg-Based Nanomaterials Combined with Solid Oxide Fuel Cell for Stationary Energy Storage

    Huaiyu Shao

    2017-11-01

    Full Text Available Mg-based materials have been investigated as hydrogen storage materials, especially for possible onboard storage in fuel cell vehicles for decades. Recently, with the development of large-scale fuel cell technologies, the development of Mg-based materials as stationary storage to supply hydrogen to fuel-cell components and provide electricity and heat is becoming increasingly promising. In this work, numerical analysis of heat balance management for stationary solid oxide fuel cell (SOFC systems combined with MgH2 materials based on a carbon-neutral design concept was performed. Waste heat from the SOFC is supplied to hydrogen desorption as endothermic heat for the MgH2 materials. The net efficiency of this model achieves 82% lower heating value (LHV, and the efficiency of electrical power output becomes 68.6% in minimizing heat output per total energy output when all available heat of waste gas and system is supplied to warm up the storage. For the development of Mg-based hydrogen storage materials, various nano-processing techniques have been widely applied to synthesize Mg-based materials with small particle and crystallite sizes, resulting in good hydrogen storage kinetics, but poor thermal conductivity. Here, three kinds of Mg-based materials were investigated and compared: 325 mesh Mg powers, 300 nm Mg nanoparticles synthesized by hydrogen plasma metal reaction, and Mg50Co50 metastable alloy with body-centered cubic structure. Based on the overall performances of hydrogen capacity, absorption kinetics and thermal conductivity of the materials, the Mg nanoparticle sample by plasma synthesis is the most promising material for this potential application. The findings in this paper may shed light on a new energy conversion and utilization technology on MgH2-SOFC combined concept.

  19. Modeling bubble heat transfer in gas-solid fluidized beds using DEM

    Patil, A.V.; Peters, E.A.J.F.; Kolkman, T.; Kuipers, J.A.M.

    2014-01-01

    Discrete element method (DEM) simulations of a pseudo 2-D fluidized bed at non-isothermal conditions are presented. First implementation details are discussed. This is followed by a validation study where heating of a packed column by a flow of heated fluid is considered. Next hot gas injected into

  20. Development of gas-solid direct contact heat exchanger by use of axial flow cyclone

    Shimizu, Akihiko; Yokomine, Takehiko [Kyushu University (Japan). Interdisciplinary Graduate School of Engineering Sciences; Nagafuchi, Tatsuro [Miura Co. Ltd., Matsuyamashi (Japan)

    2004-10-01

    A heat exchanger between particulate or granular materials and gas is developed. It makes use of a swirling gas flow similar to the usual cyclone separators but the difference from them is that the swirl making gas is issued into the cyclone chamber with downward axial velocity component. After it turns the flow direction near the bottom of the chamber, the low temperature gas receives heat from high temperature particles supplied from above at the chamber's center. Through this configuration, a direct contact and quasi counter-flow heat exchange pattern is realized so that the effective recovery of heat carried by particles is achieved. A model heat exchanger was manufactured via several numerical experiments and its performances of heat exchange as well as particle recovery were examined. Attaching a small particle diffuser below the particle-feeding nozzle brought about a drastic improvement of the heat exchange performance without deteriorating the particle recovery efficiency. The outlet gas temperature much higher than the particle outlet temperature was finally obtained, which is never realized in the parallel flow heat exchanger. (author)

  1. Quark confinement and the quark model

    Kuti, J.

    1977-01-01

    The CERN-JINR School of Physics is meant to give young experimental physicists and introduction to the theoretical aspects of recent advances in elementary particle physics. The purpose of the lectures contained in this paper is to discuss recent work on the quark model and its applications to hadron spectroscopy and some high-energy phenomena. (Auth.)

  2. Quark i mattoni del mondo

    Fritzsch, Harald

    1983-01-01

    Quark rossi, verdi e blu ; quark dotati di stranezza e di incanto ; quark 'su' e 'giù' : sembra che i fisici delle particelle giochino a confondere la curiosità del profano, con queste denominazioni fantasiose. Che cosa significano ? e, soprattutto, i quark sono i costituenti davvero elementari della materia ?

  3. Top Quark Properties at Tevatron

    Lysák, Roman [Prague, Inst. Phys.

    2017-11-27

    The latest CDF and D0 experiment measurements of the top quark properties except the top quark mass are presented. The final combination of the CDF and D0 forward-backward asymmetry measurements is shown together with the D0 measurements of the inclusive top quark pair cross-section as well as the top quark polarization.

  4. The decay width of the Z{sub c}(3900) as an axialvector tetraquark state in solid quark-hadron duality

    Wang, Zhi-Gang; Zhang, Jun-Xia [North China Electric Power University, Department of Physics, Baoding (China)

    2018-01-15

    In this article, we tentatively assign the Z{sub c}{sup ±}(3900) to be the diquark-antidiquark type axialvector tetraquark state, study the hadronic coupling constants G{sub Z{sub cJ/ψπ}}, G{sub Z{sub cη{sub cρ}}}, G{sub Z{sub cD}} {sub anti} {sub D{sup *}} with the QCD sum rules in details. We take into account both the connected and disconnected Feynman diagrams in carrying out the operator product expansion, as the connected Feynman diagrams alone cannot do the work. Special attentions are paid to matching the hadron side of the correlation functions with the QCD side of the correlation functions to obtain solid duality, the routine can be applied to study other hadronic couplings directly. We study the two-body strong decays Z{sub c}{sup +}(3900) → J/ψπ{sup +}, η{sub c}ρ{sup +}, D{sup +} anti D{sup *0}, anti D{sup 0}D{sup *+} and obtain the total width of the Z{sub c}{sup ±}(3900). The numerical results support assigning the Z{sub c}{sup ±}(3900) to be the diquark-antidiquark type axialvector tetraquark state, and assigning the Z{sub c}{sup ±}(3885) to be the meson-meson type axialvector molecular state. (orig.)

  5. Explosive Breakup of a Water Droplet with a Nontransparent Solid Inclusion Heated in a High-Temperature Gaseous Medium

    Dmitrienko Margarita A.

    2015-01-01

    Full Text Available This paper investigates the evaporation of a water droplet with a comparably sized solid nontransparent inclusion in a high-temperature (500–800 K gas medium. Water evaporates from the free surface of the inclusion. During this process, intensive vapor formation occurs on the inner interface “water droplet – solid inclusion” with the subsequent explosive decay of the droplet. Experiments have been conducted using high-speed (up to 105 fps video cameras “Phantom” and software “Phantom Camera Control”. The conditions of the explosive vapor formation of the heterogeneous water droplet were found. The typical phase change mechanisms of the heterogeneous water droplet under the conditions of intensive heat exchange were determined.

  6. Scrap tyre recycling process with molten zinc as direct heat transfer and solids separation fluid: A new reactor concept.

    Riedewald, Frank; Goode, Kieran; Sexton, Aidan; Sousa-Gallagher, Maria J

    2016-01-01

    Every year about 1.5 billion tyres are discarded worldwide representing a large amount of solid waste, but also a largely untapped source of raw materials. The objective of the method was to prove the concept of a novel scrap tyre recycling process which uses molten zinc as the direct heat transfer fluid and, simultaneously, uses this media to separate the solids products (i.e. steel and rCB) in a sink-float separation at an operating temperature of 450-470 °C. This methodology involved: •construction of the laboratory scale batch reactor,•separation of floating rCB from the zinc,•recovery of the steel from the bottom of the reactor following pyrolysis.

  7. Quark model and QCD

    Anisovich, V.V.

    1989-06-01

    Using the language of the quarks and gluons for description of the soft hadron physics it is necessary to take into account two characteristic phenomena which prevent one from usage of QCD Lagrangian in the straightforward way, chiral symmetry breaking, and confinement of colour particles. The topics discussed in this context are: QCD in the domain of soft processes, phenomenological Lagrangian for soft processes and exotic mesons, spectroscopy of low-lying hadrons (mesons, baryons and mesons with heavy quarks - c,b -), confinement forces, spectral integration over quark masses. (author) 3 refs.; 19 figs.; 3 tabs

  8. Quest for quark soup

    Goldhaber, J.

    1986-11-13

    The paper concerns the experimental search for quark-gluon plasma. The theory of a quark-gluon plasma is first given. Then the method which researchers hope will create the quark-gluon plasma is described; the idea is to use heavy ion beams in, the CERN SPS. The CERN 'heavy-ion programme' involves research groups mainly from CERN, Lawrence Berkeley Laboratory and Gellsellschaft fuer Schwerionenforschung. The experiments in the research programme are outlined, together with the detector equipment employed in the experiments.

  9. Top quark measurements at ATLAS

    Grancagnolo, Sergio; The ATLAS collaboration

    2017-01-01

    The top quark is the heaviest known fundamental particle. As it is the only quark that decays before it hadronizes, this gives us the unique opportunity to probe the properties of bare quarks at the Large Hadron Collider. This talk will present highlights of a few recent precision measurements by the ATLAS Collaboration of the top quark using 13 TeV and 8 TeV collision data: top-quark pair and single top production cross sections including differential distributions will be presented alongside top quark properties measurements. These measurements, including results using boosted top quarks, probe our understanding of top quark production in the TeV regime. Measurements of the top quark mass and searches for rare top quark decays are also presented.

  10. Top quark measurements at ATLAS

    AUTHOR|(INSPIRE)INSPIRE-00041686; The ATLAS collaboration

    2017-01-01

    The top quark is the heaviest known fundamental particle. As it is the only quark that decays before it hadronizes, it allows us to probe the properties of bare quarks at the Large Hadron Collider. Highlights of a few recent precision measurements by the ATLAS Collaboration of the top quark using 13 TeV and 8 TeV collision data will be presented: top-quark pair and single top production cross sections including differential distributions will be presented alongside measurements of top-quark properties, including results using boosted top quarks, probe our understanding of top-quark production in the TeV regime. Measurements of the top-quark mass and searches for rare top quark decays are also presented.

  11. Heat transfer monitoring in solids by means of finite element analysis software

    Hernandez W, J.; Suarez, V.; Guarachi, J.; Calderon, A.; Juarez, A. G.; Rojas T, J. B.; Marin, E.

    2012-10-01

    We study the radial heat transfer in a homogeneous and isotropic substance with a heat linear source in its axial axis. For this, we used hot wire photothermal technique in order to obtain the temperature distribution as a function of radial distance and time exposure. Also, the solution of the transient heat transport equation for this problem was obtained with appropriate boundary conditions, by means of finite element technique. The comparison of the experimental and simulated results shows a good agree, which demonstrate the utility of this methodology in the investigation of the thermal response of substances, in the radial configuration. (Author)

  12. Numerical simulation of a fractional model of temperature distribution and heat flux in the semi infinite solid

    Anupama Choudhary

    2016-03-01

    Full Text Available In this paper, a fractional model for the computation of temperature and heat flux distribution in a semi-infinite solid is discussed which is subjected to spatially decomposing, time-dependent laser source. The apt dimensionless parameters are identified and the reduced temperature and heat flux as a function of these parameters are presented in a numerical form. Some special cases of practical interest are also discussed. The solution is derived by the application of the Laplace transform, the Fourier sine transform and their derivatives. Also, we developed an alternative solution of it by using the Sumudu transform, the Fourier transform and their derivatives. These results are received in compact and graceful forms in terms of the generalized Mittag-Leffler function, which are suitable for numerical computation.

  13. Results of high heat flux tests and structural analysis of the new solid tungsten divertor tile for ASDEX Upgrade

    Jaksic, Nikola, E-mail: nikola.jaksic@ipp.mpg.de; Greuner, Henri; Herrmann, Albrecht; Böswirth, Bernd; Vorbrugg, Stefan

    2015-10-15

    Highlights: • The main motivation for the HHF investigation of tungsten tiles was an untypical deformation of some specimens under thermal loading, observed during the previous tests in GLADIS test facility. • A nonlinear finite element (FE) model for simulations of the GLADIS tests has been built. • The unexpected plastic deformations are mainly caused by internal stresses due to the manufacturing process. The small discrepancies among the FEA investigated and measured plastic deformations are most likely caused, beside of the practical difficulties by measuring of low items, also by tile internal stresses. • The influences of the residual stresses caused by special production processes have to be taken into account by design of the structural part made of solid tungsten. - Abstract: Tungsten as plasma-facing material for fusion devices is currently the most favorable candidate. In general solid tungsten is used for shielding the plasma chamber interior against the high heat generated from the plasma. For the purposes of implementation at ASDEX Upgrade and as a contribution to ITER the thermal performance of tungsten tiles has been extensively tested in the high heat flux test facility GLADIS during the development phase and beyond. These tests have been performed on full scale tungsten tile prototypes including their clamping and cooling structure. Simulating the adiabatically thermal loading due to plasma operation in ASDEX Upgrade, the tungsten tiles have been subjected to a thermal load with central heat flux of 10–24 MW/m{sup 2} and absorbed energy between 370 and 680 kJ. This loading results in maximum surface temperatures between 1300 °C and 2800 °C. The tests in GLADIS have been accompanied by intensive numerical investigations using FEA methods. For this purpose a multiple nonlinear finite element model has been set up. This paper discusses the main results of the high heat flux final tests and their numerical simulation. Moreover, first

  14. Results of high heat flux tests and structural analysis of the new solid tungsten divertor tile for ASDEX Upgrade

    Jaksic, Nikola; Greuner, Henri; Herrmann, Albrecht; Böswirth, Bernd; Vorbrugg, Stefan

    2015-01-01

    Highlights: • The main motivation for the HHF investigation of tungsten tiles was an untypical deformation of some specimens under thermal loading, observed during the previous tests in GLADIS test facility. • A nonlinear finite element (FE) model for simulations of the GLADIS tests has been built. • The unexpected plastic deformations are mainly caused by internal stresses due to the manufacturing process. The small discrepancies among the FEA investigated and measured plastic deformations are most likely caused, beside of the practical difficulties by measuring of low items, also by tile internal stresses. • The influences of the residual stresses caused by special production processes have to be taken into account by design of the structural part made of solid tungsten. - Abstract: Tungsten as plasma-facing material for fusion devices is currently the most favorable candidate. In general solid tungsten is used for shielding the plasma chamber interior against the high heat generated from the plasma. For the purposes of implementation at ASDEX Upgrade and as a contribution to ITER the thermal performance of tungsten tiles has been extensively tested in the high heat flux test facility GLADIS during the development phase and beyond. These tests have been performed on full scale tungsten tile prototypes including their clamping and cooling structure. Simulating the adiabatically thermal loading due to plasma operation in ASDEX Upgrade, the tungsten tiles have been subjected to a thermal load with central heat flux of 10–24 MW/m"2 and absorbed energy between 370 and 680 kJ. This loading results in maximum surface temperatures between 1300 °C and 2800 °C. The tests in GLADIS have been accompanied by intensive numerical investigations using FEA methods. For this purpose a multiple nonlinear finite element model has been set up. This paper discusses the main results of the high heat flux final tests and their numerical simulation. Moreover, first results

  15. Ecological solid fuels, effective heating devices for communal management and their testing methods

    Kubica, K.

    1995-12-31

    The national balance of primary energy consumption is almost 90% based upon coal. Coal is used not only in electricity production, but also in the communal sector - in heating facilities comprising chiefly local boiler houses and private households.

  16. Chemical Potential Dependence of the Dressed-Quark Propagator from an Effective Quark-Quark Interaction

    ZONG Hong-Shi; PING Jia-Lun; SUN Wei-Min; CHANG Chao-Hsi; WANG Fan

    2002-01-01

    We exhibit a method for obtaining the low chemical potential dependence of the dressed quark propagatorfrom an effective quark-quark interaction model. Within this approach we explore the chemical potential dependenceof the dressed-quark propagator, which provides a means of determining the behavior of the chiral and deconfinementorder parameters. A comparison with the results of previous researches is given.

  17. Efficient formulation of the finite element method for heat conduction in solids

    Sandsmark, N.; Aamodt, B.; Medonos, S.

    1977-01-01

    The purpose of the paper is to describe efficient methods and computer programs for analysis of heat conduction problems related to design and control of components of nuclear power plants and similar structures where thermal problems are of interest. A short presentation of basic equations and the finite element formulation of three-dimensional stationary and transient heat conduction is given. The finite element types that are used are isoparametric hexahedrons with eight or twenty nodes. The use of consistent as well as diagonal capacity matrices is discussed. Reduction of the transient heat conduction problem may be accomplished by means of the 'master-slave' technique. Furthermore, the superelement technique is discussed for both stationary and transient heat conduction. For the solution of transient problems, the trapezoidal time integration scheme is used. The methods and principles outlined in the paper are materialized in a computer program, NV615, which is one of the application programs in the program system SESAM-69. A brief description is given of NV615. Furthermore, attention is given to combined heat conduction and subsequent thermal stress analysis. Data representing geometry, calculated temperature distribution etc. may be transferred automatically from the heat conduction program to stress analysis programs. As an example of practical application the temperature distribution versus time in a turbine wheel during start up is analysed. Thermal stresses are calculated at selected time instants

  18. Our Breaths We Take: Outdoor Air Quality, Health, and Climate Change Consequences of Household Heating and Cooking with Solid Fuels

    Chafe, Zoe Anna

    Worldwide, nearly 3 billion people--40% of the global population--burn wood, coal, and other solid fuels every day to cook their food; this number is even larger when including those who heat their homes with solid fuels as well. Exposure to pollution from heating and cooking fires causes about 3 million deaths each year, making it one of the biggest environmental health problems the world faces. The harm from this smoke is not restricted to those who breathe it, however: it contains gases and particles that contribute to global climate change as well. Chapter 2 shows that household cooking with solid fuels caused an estimated 12% of population-weighted ambient PM2.5 worldwide in 2010. Exposure to this air pollution caused the loss of 370,000 lives and 9.9 million disability-adjusted life years (DALYs) globally in the same year. In Chapter 3 I demonstrate that household heating with solid fuels caused an estimated 21% of population-weighted ambient PM2.5 in 2010 in Central Europe, 13% in Eastern Europe, 12% in Western Europe, and 8% in North America. Exposure to this air pollution results caused approximately 60,000 premature deaths in Europe, and nearly 10,000 deaths in North America, as well as an estimated 1.0 million disability-adjusted life years (DALYs) in Europe and 160,000 DALYs in North America. Chapter 4 addresses drivers of household wood combustion pollution in the San Francisco Bay Area, where the sector is the largest source of PM 2.5 and regulators recently introduced amendments to wood burning rules for the airshed. Fireplaces are the source of the vast majority (84%) of PM 2.5 from residential wood combustion in the San Francisco Bay Area, despite their use primarily as an aesthetic or recreational combustion activity. By evaluating hypothetical fuel and combustion device changeouts, I find that replacing fireplaces with gas would yield significant health and economic benefits. Specifically, retrofitting frequently used fireplaces (300,000 units

  19. Thermodynamic analysis of Direct Urea Solid Oxide Fuel Cell in combined heat and power applications

    Abraham, F.; Dincer, I.

    2015-12-01

    This paper presents a comprehensive steady state modelling and thermodynamic analysis of Direct Urea Solid Oxide Fuel Cell integrated with Gas Turbine power cycle (DU-SOFC/GT). The use of urea as direct fuel mitigates public health and safety risks associated with the use of hydrogen and ammonia. The integration scheme in this study covers both oxygen ion-conducting solid oxide fuel cells (SOFC-O) and hydrogen proton-conducting solid oxide fuel cells (SOFC-H). Parametric case studies are carried out to investigate the effects of design and operating parameters on the overall performance of the system. The results reveal that the fuel cell exhibited the highest level of exergy destruction among other system components. Furthermore, the SOFC-O based system offers better overall performance than that with the SOFC-H option mainly due to the detrimental reverse water-gas shift reaction at the SOFC anode as well as the unique configuration of the system.

  20. Strong interactions - quark models

    Goto, M.; Ferreira, P.L.

    1979-01-01

    The variational method is used for the PSI and upsilon family spectra reproduction from the quark model, through several phenomenological potentials, viz.: linear, linear plus coulomb term and logarithmic. (L.C.) [pt

  1. Multileptons from heavy quarks

    Phillips, R.J.N.

    1984-03-01

    The paper is concerned with a brief look at the various multilepton signals that are expected at p-barp colliders from the production and cascade decay of top quarks, plus the backgrounds from b and c production. (author)

  2. Quarks in nuclei

    Roberts, R.G.

    1984-11-01

    The paper concerns the behaviour of quarks in nuclei. Confinement size changes and dynamical rescaling; A dependence; low-x region; gluons and confinement size; and nucleons in a nucleus; are all discussed. (U.K.)

  3. The quark bag model

    Hasenfratz, P.; Kuti, J.

    1978-01-01

    The quark bag model is reviewed here with particular emphasis on spectroscopic applications and the discussion of exotic objects as baryonium, gluonium, and the quark phase of matter. The physical vacuum is pictured in the model as a two-phase medium. In normal phase of the vacuum, outside hadrons, the propagation of quark and gluon fields is forbidden. When small bubbles in a second phase are created in the medium of the normal phase with a characteristic size of one fermi, the hadron constituent fields may propagate inside the bubbles in normal manner. The bubble (bag) is stabilized against the pressure of the confined hadron constituent fields by vacuum pressure and surface tension. Inside the bag the colored quarks and gluons are governed by the equations of quantum chromodynamics. (Auth.)

  4. Color quarks and octonions

    Guersey, F.

    1974-01-01

    A mathematical framework based on octonions is developed for the description of the color quark scheme in which quarks are unobservable, the color SU(3) is exact, and only color singlets correspond to observable hadrons. The fictitious Hilbert space in which quarks operate is taken to be a space of vectors with octonion components. This space admits as a gauge group an exact SU(3) identified with the color SU/sub C/(3). Because of the nonassociativity of the underlying algebra, nonsinglet representations of SU/sub C/(3) are unobservable, while the subspace of color singlets satisfies associativity along with conditions for observability. Octonion quark fields satisfy the commutation relations of parafermions of order 3, leading to the correct SU(6) multiplets for hadrons. (U.S.)

  5. Top quark discovered

    Anon.

    1995-01-01

    Nine months after a careful announcement of tentative evidence for the long-awaited sixth 'top' quark, physicists from the CDF and DO experiments at Fermilab's Tevatron proton-antiproton collider declared on 2 March that they had finally discovered the top quark. Last year (June 1994, page 1), the CDF experiment at the Tevatron reported a dozen candidate top events. These, said CDF, had all the characteristics expected of top, but the difficulties of extracting the tiny signal from a trillion proton-antiproton collisions made them shy of claiming a discovery. For its part, the companion DO Tevatron experiment reported a few similar events but were even more guarded about their interpretation as top quarks. Just after these hesitant announcements, performance at the Tevatron improved dramatically last summer. After the commissioning of a new linear accelerator and a magnet realignment, the machine reached a new world record proton-antiproton collision luminosity of 1.28 x 10 31 per sq cm per s, ten times that originally planned. Data began to pour in at an unprecedented rate and the data sample grew to six trillion collisions. Luminosity has subsequently climbed to 1.7 x 10 31 . The top quark is the final letter in the alphabet of Standard Model particles. According to this picture, all matter is composed of six stronglyinteracting subnuclear particles, the quarks, and six weakly interacting particles, the leptons. Both sextets are neatly arranged as three pairs in order of increasing mass. The fifth quark, the 'beauty' or 'b' quark, was also discovered at Fermilab, back in 1977. Since then physicists have been eagerly waiting for the top to turn up, but have been frustrated by its heaviness - the top is some 40 times the mass of its 'beautiful' partner. Not only is the top quark the heaviest by far, but it is the only quark which has been actively hunted. After the quarry was glimpsed last year, the net has now been

  6. Do Quarks Propagate?

    Sørensen, Paul Haase; Taylor, John C.

    1984-01-01

    Processes with coloured particles in the initial state are generally infrared divergent. We investigate the effect of this on processes with colourless particles in the initial state, when the amplitude is near an intermediate quark pole. The result is a characteristic logarithmic depedence...... on the 'binding energy'(even though spectator interactions are taken into account), and the result is gauge-invariant. Summed to all orders the logarithms could perhaps suppress the quark pole....

  7. Electricity and combined heat and power from municipal solid waste; theoretically optimal investment decision time and emissions trading implications.

    Tolis, Athanasios; Rentizelas, Athanasios; Aravossis, Konstantin; Tatsiopoulos, Ilias

    2010-11-01

    Waste management has become a great social concern for modern societies. Landfill emissions have been identified among the major contributors of global warming and climate changes with significant impact in national economies. The energy industry constitutes an additional greenhouse gas emitter, while at the same time it is characterized by significant costs and uncertain fuel prices. The above implications have triggered different policies and measures worldwide to address the management of municipal solid wastes on the one hand and the impacts from energy production on the other. Emerging methods of energy recovery from waste may address both concerns simultaneously. In this work a comparative study of co-generation investments based on municipal solid waste is presented, focusing on the evolution of their economical performance over time. A real-options algorithm has been adopted investigating different options of energy recovery from waste: incineration, gasification and landfill biogas exploitation. The financial contributors are identified and the impact of greenhouse gas trading is analysed in terms of financial yields, considering landfilling as the baseline scenario. The results indicate an advantage of combined heat and power over solely electricity production. Gasification, has failed in some European installations. Incineration on the other hand, proves to be more attractive than the competing alternatives, mainly due to its higher power production efficiency, lower investment costs and lower emission rates. Although these characteristics may not drastically change over time, either immediate or irreversible investment decisions might be reconsidered under the current selling prices of heat, power and CO(2) allowances.

  8. Semi-solid near-net shape rheocasting of heat treatable wrought aluminum alloys

    Curle, UA

    2010-09-01

    Full Text Available Flexibility of the CSIR-RCS, induction stirring with simultaneous air cooling process, in combination with high pressure die casting is successfully demonstrated by semi-solid rheocasting of plates performed on commercial 2024, 6082 and 7075 wrought...

  9. Optimizing the Costs of Solid Sorbent-Based CO2 Capture Process Through Heat Integration

    Sjostrom, Sharon [Ada-Es, Inc., Highlands Ranch, CO (United States)

    2016-03-18

    that reductions in adsorber pressure drop could negatively affect the CO2 adsorption characteristics for sorbents with certain isobar adsorption characteristics like sorbent BN. Thus, reductions in pressure drop do not provide the efficiency benefits expected. A techno-economic assessment conducted during the project revealed that without heat integration, the a metal organic framework (MOF) sorbent used in conjunction with the ADAsorb™ process provided the opportunity for improved performance over the benchmark MEA process. While the addition of a cross heat exchanger and heat integration was found to significantly improve net unit heat rate, the additional equipment costs required to realize these improvements almost always outweighed the improvement in performance. The exception to this was for a supported amine sorbent and the addition of a moving bed cross heat exchanger alone or in conjunction with waste heat from the compressor used for supplemental regenerator heating. Perhaps one of the most important points to be drawn from the work conducted during this project is the significant influence of sorbent characteristics alone on the projected COE and LCOE associated with the ADAsorb™ process, and the implications associated with future improvements to solid sorbent CO2 capture. The results from this project suggest that solid sorbent CO2 capture will continue to see performance gains and lower system costs as further sorbent improvements are realized.

  10. Transient solid-liquid He heat transfer and onset of film boiling

    Metzger, W.; Huebener, R.P.; Selig, K.P.

    1982-01-01

    The transient heat transfer between single-crystalline Ge chips and liquid helium is investigated during the application of light pulses with different optical power to the Ge sample. The strong temperature dependence of the electrical conductivity of Ge conveniently serves for monitoring the temporal behaviour of the sample temperature during the input of optical energy. After a certain time interval following the beginning of the light pulse an abrupt rise of the sample temperature is observed. This time interval is much longer than the thermal time constant expected for the sample. This abrupt rise of the sample temperature can be understood in terms of the onset of film boiling. The observed onset time of film boiling and its dependence upon the heat transfer power density agrees reasonably with earlier results by Steward (Int. J. Heat Mass Transfer 21; 863. (1978)). (author)

  11. The composition, heating value and renewable share of the energy content of mixed municipal solid waste in Finland

    Horttanainen, M.; Teirasvuo, N.; Kapustina, V.; Hupponen, M.; Luoranen, M.

    2013-01-01

    Highlights: • New experimental data of mixed MSW properties in a Finnish case region. • The share of renewable energy of mixed MSW. • The results were compared with earlier international studies. • The average share of renewable energy was 30% and the average LHVar 19 MJ/kg. • Well operating source separation decreases the renewable energy content of MSW. - Abstract: For the estimation of greenhouse gas emissions from waste incineration it is essential to know the share of the renewable energy content of the combusted waste. The composition and heating value information is generally available, but the renewable energy share or heating values of different fractions of waste have rarely been determined. In this study, data from Finnish studies concerning the composition and energy content of mixed MSW were collected, new experimental data on the compositions, heating values and renewable share of energy were presented and the results were compared to the estimations concluded from earlier international studies. In the town of Lappeenranta in south-eastern Finland, the share of renewable energy ranged between 25% and 34% in the energy content tests implemented for two sample trucks. The heating values of the waste and fractions of plastic waste were high in the samples compared to the earlier studies in Finland. These high values were caused by good source separation and led to a low share of renewable energy content in the waste. The results showed that in mixed municipal solid waste the renewable share of the energy content can be significantly lower than the general assumptions (50–60%) when the source separation of organic waste, paper and cardboard is carried out successfully. The number of samples was however small for making extensive conclusions on the results concerning the heating values and renewable share of energy and additional research is needed for this purpose

  12. The composition, heating value and renewable share of the energy content of mixed municipal solid waste in Finland

    Horttanainen, M., E-mail: mika.horttanainen@lut.fi; Teirasvuo, N.; Kapustina, V.; Hupponen, M.; Luoranen, M.

    2013-12-15

    Highlights: • New experimental data of mixed MSW properties in a Finnish case region. • The share of renewable energy of mixed MSW. • The results were compared with earlier international studies. • The average share of renewable energy was 30% and the average LHVar 19 MJ/kg. • Well operating source separation decreases the renewable energy content of MSW. - Abstract: For the estimation of greenhouse gas emissions from waste incineration it is essential to know the share of the renewable energy content of the combusted waste. The composition and heating value information is generally available, but the renewable energy share or heating values of different fractions of waste have rarely been determined. In this study, data from Finnish studies concerning the composition and energy content of mixed MSW were collected, new experimental data on the compositions, heating values and renewable share of energy were presented and the results were compared to the estimations concluded from earlier international studies. In the town of Lappeenranta in south-eastern Finland, the share of renewable energy ranged between 25% and 34% in the energy content tests implemented for two sample trucks. The heating values of the waste and fractions of plastic waste were high in the samples compared to the earlier studies in Finland. These high values were caused by good source separation and led to a low share of renewable energy content in the waste. The results showed that in mixed municipal solid waste the renewable share of the energy content can be significantly lower than the general assumptions (50–60%) when the source separation of organic waste, paper and cardboard is carried out successfully. The number of samples was however small for making extensive conclusions on the results concerning the heating values and renewable share of energy and additional research is needed for this purpose.

  13. Device for measuring high temperature heat conductivity of solids and melts

    Magomedov, Ya.B.; Gadzhiev, G.G.

    1990-01-01

    A modification of a device for measuring heat conductivity by a compensation method when a thermocouple with gadolinium sulfide being used is suggested. Such a device has less error of measurement (8%), wider interval of working temperatures (300-1600K) and it permits to investigate the material in the wide range of heat conductivity values (0.5-30 W/(mxK)). The stainless steel 12Kh18N10T, lanthanum sulfide and melted quartz were used for the device calibration. The results obtained and the literature data on these materials agree well between each other

  14. Prediction of new Quarks, Generations and Quark Masses

    Lach, Thedore

    2002-04-01

    The Standard model currently suggests no relationship between the quark and lepton masses. The CBM (model) of the nucleus has resulted in the prediction of two new quarks, an up quark mass of 237.31 MeV/c2 and a dn quark mass of 42.392 MeV/c2. These two new quarks help explain the numerical relationship between all the quark and lepton masses in a single function. The mass of each SNU-P (quark or lepton) is just the geometric mean of two related SNU-Ps, either in the same generation or in the same family. This numerology predicts the following masses for the electron family: 0.511000 (electron), 7.743828 (predicted), 117.3520, 1778.38, 26950.08 MeV. The resulting slope of these masses when plotted on semi log paper is "e" to 5 significant figures using the currently accepted mass for Tau. This theory suggests that all the "dn like" quarks have a mass of just 10X multiples of 4.24 MeV (the mass of the "d" quark). The first 3 "up like" quark masses are 38, 237 and 1500 MeV. This theory also predicts a new heavy generation with a lepton mass of 27 GeV, a "dn like" quark of 42.4 GeV, and an "up like" quark of 65 GeV. Significant evidence already exists for the existence of these quarks, and lepton.

  15. Nuclear heat-load limits for above-grade storage of solid transuranium wastes

    Clontz, B.G.

    1978-06-01

    Nuclear safety and heat load limits were established for above-grade storage of transuranium (TRU) wastes. Nuclear safety limits were obtained from a study by J.L. Forstner and are summarized. Heat load limits are based on temperature calculations for TRU waste drums stored in concrete containers (hats), and results are summarized. Waste already in storage is within these limits. The limiting factors for individual drum heat load limits were (1) avoidance of temperatures in excess of 190 0 F (decomposition temperature of anion resin) when anion resin is present in a concrete hat, and (2) avoidance of temperatures in excess of 450 0 F (ignition temperature of paper) at any point inside a waste drum. The limiting factor for concrete had heat load limits was avoidance of temperatures in excess of 265 0 F (melt point of high density polyethylene) at the drum liners. A temperature profile for drums and hats filled to recommended limits is shown. Equations and assumptions used were conservative

  16. The effect of heat currents on the stability of the liquid solid interface

    Bowley, R.M.; Nozieres, P.

    1992-01-01

    Rapid changing of the temperature of a liquid in equilibrium with its solid can lead to instabilities of the interface in two ways : the change in pressure, induced by a temperature change at the interface, leads to a uniaxial stress which can cause a Grinfeld instability at the capillary wavelength; a temperature gradient is set up which modifies the effective gravity at the interface. When the effective gravity becomes negative, the interface is unstable at very long wavelengths. For a superfluid, such as 4 He, the situation is more complex. If we ignore surface dissipation, there is still a small critical temperature gradient across the solid above which the interface is unstable. However surface dissipation -in particular the growth resistance- pushes the instability to huge temperature gradients, ones which cannot be realised experimentally. The only instability that can be seen is caused by uniaxial stress

  17. Heat-shrink tubing as a solid-phase microextraction coating for the enrichment and determination of phthalic acid esters.

    Luo, Xi; He, Chengxia; Zhang, Feifang; Wang, Hailong; Yang, Bingcheng; Liang, Xinmiao

    2014-12-01

    Heat-shrink tubing, which shrinks in one plane only (its diameter) when heated, commonly used for sealing protection in electrical engineering, was found to be able to function as a solid-phase microextraction coating. Its utility was demonstrated for the determination of phthalic acid esters in an aqueous solution combined with high-performance liquid chromatography equipped with a UV absorbance detector. The preparation procedure was rather simple and only ∼10 min was needed. The fiber cost is extremely low (∼10 cent each). The parameters affecting the extraction were optimized. Heat-shrink tubing fiber exhibited a significant enrichment effect for the three examined phthalic acid esters and up to 931-fold enrichment factor was obtained. The limit of detection was <10 μg/L for all analytes. The operation repeatability and fiber-to-fiber reproducibility were 1.2-8.3 and 5.4-9.1%, respectively. It was successfully applied for the analysis of bottled drinking water with recoveries ranging from 90.1-100.5%. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. A fluid-solid coupling simulation method for convection heat transfer coefficient considering the under-vehicle condition

    Tian, C.; Weng, J.; Liu, Y.

    2017-11-01

    The convection heat transfer coefficient is one of the evaluation indexes of the brake disc performance. The method used in this paper to calculate the convection heat transfer coefficient is a fluid-solid coupling simulation method, because the calculation results through the empirical formula method have great differences. The model, including a brake disc, a car body, a bogie and flow field, was built, meshed and simulated in the software FLUENT. The calculation models were K-epsilon Standard model and Energy model. The working condition of the brake disc was considered. The coefficient of various parts can be obtained through the method in this paper. The simulation result shows that, under 160 km/h speed, the radiating ribs have the maximum convection heat transfer coefficient and the value is 129.6W/(m2·K), the average coefficient of the whole disc is 100.4W/(m2·K), the windward of ribs is positive-pressure area and the leeward of ribs is negative-pressure area, the maximum pressure is 2663.53Pa.

  19. Effect of materials mixture on the higher heating value: Case of biomass, biochar and municipal solid waste.

    Boumanchar, Imane; Chhiti, Younes; M'hamdi Alaoui, Fatima Ezzahrae; El Ouinani, Amal; Sahibed-Dine, Abdelaziz; Bentiss, Fouad; Jama, Charafeddine; Bensitel, Mohammed

    2017-03-01

    The heating value describes the energy content of any fuel. In this study, this parameter was evaluated for different abundant materials in Morocco (two types of biochar, plastic, synthetic rubber, and cardboard as municipal solid waste (MSW), and various types of biomass). Before the evaluation of their higher heating value (HHV) by a calorimeter device, the thermal behavior of these materials was investigated using thermogravimetric (TGA) and Differential scanning calorimetry (DSC) analyses. The focus of this work is to evaluate the calorific value of each material alone in a first time, then to compare the experimental and theoretical HHV of their mixtures in a second time. The heating value of lignocellulosic materials was between 12.16 and 20.53MJ/kg, 27.39 for biochar 1, 32.60MJ/kg for biochar 2, 37.81 and 38.00MJ/kg for plastic and synthetic rubber respectively and 13.81MJ/kg for cardboard. A significant difference was observed between the measured and estimated HHVs of mixtures. Experimentally, results for a large variety of mixture between biomass/biochar and biomass/MSW have shown that the interaction between biomass and other compounds expressed a synergy of 2.37% for biochar 1 and 6.11% for biochar 2, 1.09% for cardboard, 5.09% for plastic and 5.01% for synthetic rubber. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Neutrino emission in inhomogeneous pion condensed quark matter

    Huang, Xuguang; Wang, Qun; Zhuang, Pengfei

    2008-01-01

    It is believed that quark matter can exist in neutron star interior if the baryon density is high enough. When there is a large isospin density, quark matter could be in a pion condensed phase. We compute neutrino emission from direct Urca processes in such a phase, particularly in the inhomogeneous Larkin-Ovchinnikov-Fulde-Ferrell (LOFF) states. The neutrino emissivity and specific heat are obtained, from which the cooling rate is estimated. (author)

  1. A high-temperature furnace and a heating/drawing device designed for time-resolved X-ray diffraction measurements of polymer solids using imaging plates

    Murakami, Syozo; Tanno, Kiyomitsu; Tsuji, Masaki; Kohjiya, Shinzo

    1995-01-01

    For time-resolved X-ray diffraction measurements using the imaging plate system in the drawing and/or heating process of polymer solids, a high-temperature furnace for heat treatment and a heating/drawing device were newly designed and constructed. Then, to demonstrate their performance, some experimental results obtained in the drawing process of an extruded/blown film of high-density polyethylene at room temperature and in the crystallization process of an oriented amorphous film of poly(ethylene naphthalene-2,6-dicarboxylate) by heating were presented. Other experimental results obtained using them were also briefly cited. (author)

  2. Bootstrapping quarks and gluons

    Chew, G.F.

    1979-04-01

    Dual topological unitarization (DTU) - the approach to S-matrix causality and unitarity through combinatorial topology - is reviewed. Amplitudes associated with triangulated spheres are shown to constitute the core of particle physics. Each sphere is covered by triangulated disc faces corresponding to hadrons. The leading current candidate for the hadron-face triangulation pattern employs 3-triangle basic subdiscs whose orientations correspond to baryon number and topological color. Additional peripheral triangles lie along the hadron-face perimeter. Certain combinations of peripheral triangles with a basic-disc triangle can be identified as quarks, the flavor of a quark corresponding to the orientation of its edges that lie on the hadron-face perimeter. Both baryon number and flavor are additively conserved. Quark helicity, which can be associated with triangle-interior orientation, is not uniformly conserved and interacts with particle momentum, whereas flavor does not. Three different colors attach to the 3 quarks associated with a single basic subdisc, but there is no additive physical conservation law associated with color. There is interplay between color and quark helicity. In hadron faces with more than one basic subdisc, there may occur pairs of adjacent flavorless but colored triangles with net helicity +-1 that are identifiable as gluons. Broken symmetry is an automatic feature of the bootstrap. T, C and P symmetries, as well as up-down flavor symmetry, persist on all orientable surfaces.

  3. The quark matter

    Rho, Mannque.

    1980-04-01

    The present status of our understanding of the physics of hadronic (nuclear or neutron) matter under extreme conditions, in particular at high densities is discussed. This is a problem which challenges three disciplines of physics: nuclear physics, astrophysics and particle physics. It is generally believed that we now have a correct and perhaps ultimate theory of the strong interactions, namely quantum chromodynamics (QCD). The constituents of this theory are quarks and gluons, so highly dense matters should be describable in terms of these constituents alone. This is a question that addresses directly to the phenomenon of quark confinement, one of the least understood aspects in particle physics. For nuclear physics, the possibility of a phase change between nuclear matter and quark matter introduces entirely new degrees of freedom in the description of nuclei and will bring perhaps a deeper understanding of nuclear dynamics. In astrophysics, the properties of neutron stars will be properly understood only when the equation of state of 'neutron' matter at densities exceeding that of nuclear matter can be realiably calculated. Most fascinating is the possibility of quark stars existing in nature, not entirely an absurd idea. Finally the quark matter - nuclear matter phase transition must have occured in the early stage of universe when matter expanded from high temperature and density; this could be an essential ingredient in the big-bang cosmology

  4. Bootstrapping quarks and gluons

    Chew, G.F.

    1979-04-01

    Dual topological unitarization (DTU) - the approach to S-matrix causality and unitarity through combinatorial topology - is reviewed. Amplitudes associated with triangulated spheres are shown to constitute the core of particle physics. Each sphere is covered by triangulated disc faces corresponding to hadrons. The leading current candidate for the hadron-face triangulation pattern employs 3-triangle basic subdiscs whose orientations correspond to baryon number and topological color. Additional peripheral triangles lie along the hadron-face perimeter. Certain combinations of peripheral triangles with a basic-disc triangle can be identified as quarks, the flavor of a quark corresponding to the orientation of its edges that lie on the hadron-face perimeter. Both baryon number and flavor are additively conserved. Quark helicity, which can be associated with triangle-interior orientation, is not uniformly conserved and interacts with particle momentum, whereas flavor does not. Three different colors attach to the 3 quarks associated with a single basic subdisc, but there is no additive physical conservation law associated with color. There is interplay between color and quark helicity. In hadron faces with more than one basic subdisc, there may occur pairs of adjacent flavorless but colored triangles with net helicity +-1 that are identifiable as gluons. Broken symmetry is an automatic feature of the bootstrap. T, C and P symmetries, as well as up-down flavor symmetry, persist on all orientable surfaces

  5. Light induced cooling of a heated solid immersed in liquid helium I

    Lezak, D.; Brodie, L.C.; Semura, J.S.

    1984-01-01

    This chapter investigates the marked enhancement in the transient heat transfer from the heater-thermometer to the liquid helium immediately following the application of a flash of visible light. This ''light effect'' is associated with increased bubble activity, and it is possible that the light induces a rapid nucleation of bubbles in the superheated liquid at or near the heater surface. A summary of the light effect is presented and some potential uses to which this effect could be applied are suggested. Quantification of the light effect and properties of the light effect are discussed. It is determined that the light effect is an additional cooling due to a light induced enhancement of boiling in superheated liquid helium I. The effect could be applied in practical cryogenic engineering and for the acquisition of fundamental knowledge of boiling heat transfer and nucleation in cryogenic liquids

  6. Heavy quark fragmentation functions in the heavy quark effective theory

    Martynenko, A.P.; Saleev, V.A.

    1996-01-01

    The fragmentation of b-bar-antiquark into polarized B c * -mesons and b-quark into P-wave (c-bar b) states in the Heavy Quark Effective Theory. The heavy quark fragmentation functions in longitudinally and transversely polarized S-wave b-bar c-states and P-wave mesons containing b-, c-quarks also, with the exact account of corrections of first order in 1/m b . 20 refs., 2 figs

  7. Structural characterization of heat treated pitch by solid state /sup 13/C nuclear magnetic resonance spectroscopy

    Sfihi, H.; Tougne, P.; Legrand, A.P.; Couderc, P.; Saint-Romain, J.L.

    1988-12-01

    The objective of this paper is to determine structural parameters (aromaticity factor, fractions of protonated and non-protonated aromatic carbons) of some pitches, and to follow their evolution as a function of the heat treatment duration. For such a determination, /sup 13/C-/sup 1/H cross polarization combined with magic angle spinning and dipolar dephasing (CP/MAS/DD) NMR was used. 15 refs., 4 figs., 1 tab.

  8. A non-linear, finite element, heat conduction code to calculate temperatures in solids of arbitrary geometry

    Tayal, M.

    1987-01-01

    Structures often operate at elevated temperatures. Temperature calculations are needed so that the design can accommodate thermally induced stresses and material changes. A finite element computer called FEAT has been developed to calculate temperatures in solids of arbitrary shapes. FEAT solves the classical equation for steady state conduction of heat. The solution is obtained for two-dimensional (plane or axisymmetric) or for three-dimensional problems. Gap elements are use to simulate interfaces between neighbouring surfaces. The code can model: conduction; internal generation of heat; prescribed convection to a heat sink; prescribed temperatures at boundaries; prescribed heat fluxes on some surfaces; and temperature-dependence of material properties like thermal conductivity. The user has a option of specifying the detailed variation of thermal conductivity with temperature. For convenience to the nuclear fuel industry, the user can also opt for pre-coded values of thermal conductivity, which are obtained from the MATPRO data base (sponsored by the U.S. Nuclear Regulatory Commission). The finite element method makes FEAT versatile, and enables it to accurately accommodate complex geometries. The optional link to MATPRO makes it convenient for the nuclear fuel industry to use FEAT, without loss of generality. Special numerical techniques make the code inexpensive to run, for the type of material non-linearities often encounter in the analysis of nuclear fuel. The code, however, is general, and can be used for other components of the reactor, or even for non-nuclear systems. The predictions of FEAT have been compared against several analytical solutions. The agreement is usually better than 5%. Thermocouple measurements show that the FEAT predictions are consistent with measured changes in temperatures in simulated pressure tubes. FEAT was also found to predict well, the axial variations in temperatures in the end-pellets(UO 2 ) of two fuel elements irradiated

  9. Simultaneous Effects of Total Solids Content, Milk Base, Heat Treatment Temperature and Sample Temperature on the Rheological Properties of Plain Stirred Yogurt

    Attilio Converti

    2006-01-01

    Full Text Available Response surface methodology was used to establish a relationship between total solids content, milk base, heat treatment temperature, and sample temperature, and consistency index, flow behaviour index, and apparent viscosity of plain stirred yogurts. Statistical treatments resulted in developments of mathematical models. All samples presented shear thinning fluid behaviour. The increase of the content of total solids (9.3–22.7 % and milk base heat treatment temperature (81.6–98.4 °C resulted in a significant increase in consistency index and a decrease in flow behaviour index. Increase in the sample temperature (1.6–18.4 °C caused a decrease in consistency index and increase in flow behaviour index. Apparent viscosity was directly related to the content of total solids. Rheological properties of yogurt were highly dependent on the content of total solids in milk.

  10. Detecting heavy quarks

    Benenson, G.; Chau, L.L.; Ludlam, T.; Paige, F.E.; Platner, E.D.; Protopopescu, S.D.; Rehak, P.

    1983-01-01

    In this exercise we examine the performance of a detector specifically configured to tag heavy quark (HQ) jets through direct observations of D-meson decays with a high resolution vertex detector. To optimize the performance of such a detector, we assume the small diamond beam crossing configuration as described in the 1978 ISABELLE proposal, giving a luminosity of 10 32 cm -2 sec -1 . Because of the very large backgrounds from light quark (LQ) jets, most triggering schemes at this luminosity require high P/sub perpendicular to/ leptons and inevitably give missing neutrinos. If alternative triggering schemes could be found, then one can hope to find and calculate the mass of objects decaying to heavy quarks. A scheme using the high resolution detector will also be discussed in detail. The study was carried out with events generated by the ISAJET Monte Carlo and a computer simulation of the described detector system

  11. Top Quark Mass

    Mulders, Martijn

    2016-01-01

    Ever since the discovery of the top quark at the Tevatron collider in 1995 the measurement of its mass has been a high priority. As one of the fundamental parameters of the Standard Theory of particle physics, the precise value of the top quark mass together with other inputs provides a test for the self-consistency of the theory, and has consequences for the stability of the Higgs field that permeates the Universe. In this review I will briefly summarize the experimental techniques used at the Tevatron and the LHC experiments throughout the years to measure the top quark mass with ever improving accuracy, and highlight the recent progress in combining all measurements in a single world average combination. As experimental measurements became more precise, the question of their theoretical interpretation has become important. The difficulty of relating the measured quantity to the fundamental top mass parameter has inspired alternative measurement methods that extract the top mass in complementary ways. I wil...

  12. The Quark's Model and Confinement

    Novozhilov, Yuri V.

    1977-01-01

    Quarks are elementary particles considered to be components of the proton, the neutron, and others. This article presents the quark model as a mathematical concept. Also discussed are gluons and bag models. A bibliography is included. (MA)

  13. Heavy quarks at hadron colliders

    Paige, F.E.

    1989-01-01

    This paper discusses a conference at which the standard model requiring the existence of a top quark + to form a weak isospin doublet with the b quark is explored. Collaboration suggestions are offered. Results are explored

  14. Reducing residential solid fuel combustion through electrified space heating leads to substantial air quality, health and climate benefits in China's Beijing-Tianjin-Hebei region

    Yang, J.; Mauzerall, D. L.

    2017-12-01

    During periods of high pollution in winter, household space heating can contribute more than half of PM2.5 concentrations in China's Beijing-Tianjin-Hebei (BTH) region. The majority of rural households and some urban households in the region still heat with small stoves and solid fuels such as raw coal, coal briquettes and biomass. Thus, reducing emissions from residential space heating has become a top priority of the Chinese government's air pollution mitigation plan. Electrified space heating is a promising alternative to solid fuel. However, there is little analysis of the air quality and climate implications of choosing various electrified heating devices and utilizing different electricity sources. Here we conduct an integrated assessment of the air quality, human health and climate implications of various electrified heating scenarios in the BTH region using the Weather Research and Forecasting model with Chemistry. We use the Multi-resolution Emission Inventory for China for the year 2012 as our base case and design two electrification scenarios in which either direct resistance heaters or air source heat pumps are installed to replace all household heating stoves. We initially assume all electrified heating devices use electricity from supercritical coal-fired power plants. We find that installing air source heat pumps reduces CO2 emissions and premature deaths due to PM2.5 pollution more than resistance heaters, relative to the base case. The increased health and climate benefits of heat pumps occur because they have a higher heat conversion efficiency and thus require less electricity for space heating than resistance heaters. We also find that with the same heat pump installation, a hybrid electricity source (40% of the electricity generated from renewable sources and the rest from coal) further reduces both CO2 emissions and premature deaths than using electricity only from coal. Our study demonstrates the air pollution and CO2 mitigation potential and

  15. Clustering in a quark gas

    Welke, G.M.; Heiss, W.D.

    1986-01-01

    In an infinite one-dimensional quark gas it is shown that a static color force, which increases at large distance, leads to a density fluctuation in the ground state. A self-consistent mean field can only be found for an effectively attractive quark-quark interaction that increases less than linearly at large distances. For a fixed coupling constant, the clustering disappears at high quark density

  16. Quark chemistry: charmonium molecules

    De Rujula, A.; Jaffe, R.L.

    1977-01-01

    The theoretical and experimental evidence for two quark-two antiquark hadrons is reviewed. Concentration is placed on predictions for S-wave ''charmonium molecules,'' built of a c anti c charmonium pair and a light quark-antiquark pair. Their spectrum and quantum numbers are predicted and an estimate of their decay couplings and their prediction in monochromatic pion decays from charmonium resonances produced in e + e - -annihilation is given. Some S-wave charmonium resonances should be detectable in these decays, but typical branching ratios are only at the 1% level. 19 references

  17. Thermodynamics of quark gas

    Biswas, S. N.

    1980-07-01

    The application of quantum statistical mechanics to a system of particles consisting of quarks is considered. Realistic theoretical investigations have been underway to understand highly dense objects such as white dwarfs and neutron stars. The various possibilities in the case of very high densities such as 10/sup 15/ or 10/sup 16/ g/cm/sup 3/ are enumerated. The thermodynamics of a phase transition from neutron matter phase to quark matter phase is analysed. Preliminary results based on quantum chromodynamics and other phenomenological models are reported.

  18. Quarks in nuclei

    Rho, M.; CEA Centre d'Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette

    1983-01-01

    Some features of quark degrees of freedom in nuclei are discussed in the light of recent developments in QCD. The principal aim of this talk is to propose, and give a tentative support to, the motion that one can study through nuclear matter different facets of the vacuum structure implied by quantum chromodynamics (QCD). This will be done using the recent (exciting) results obtained in particle physics, in particular lattice gauge calculations. Relevance of this aspect of problem to quark degrees of freedom as well as meson degrees of freedom in nuclei will be discussed. (orig.)

  19. Quark Orbital Angular Momentum

    Burkardt Matthias

    2015-01-01

    Full Text Available Definitions of orbital angular momentum based on Wigner distributions are used as a framework to discuss the connection between the Ji definition of the quark orbital angular momentum and that of Jaffe and Manohar. We find that the difference between these two definitions can be interpreted as the change in the quark orbital angular momentum as it leaves the target in a DIS experiment. The mechanism responsible for that change is similar to the mechanism that causes transverse single-spin asymmetries in semi-inclusive deep-inelastic scattering.

  20. Quark search conference

    Anon.

    1981-01-01

    In spite of (or perhaps because of) the present doctrine of total quark confinement held by the majority of particle theorists, experimental searches for free fractional charge and other anomalous stable particles in ordinary matter have been increasing in number during recent years, using a range of techniques of increasing sophistication and sensitivity. As a result, researchers in this area had a conference to themselves in June. About 40 participants and 150 observers gathered at San Francisco State University to report progress and discuss future plans, with representatives present from almost every group involved in quark searches

  1. Consistency in thermophysical properties: enthalpy, heat capacity, thermal conductivity and thermal diffusivity of solid UO2

    Fink, J.K.; Chasanov, M.G.; Leibowitz, L.

    Equations have been derived for the enthalpy, heat capacity, thermal conductivity, and thermal diffusivity of UO 2 . In selection of these equations, we considered the traditional criterion of lowest relative standard deviation between experimental data and the function chosen to fit these data as well as consistency between the thermophysical properties. In the latter case, we considered consistency in (1) thermodynamic relations among properties, (2) the choice of physical phenomena on which to base the theoretical formulation of the equations, and (3) the existence and temperature of phase transitions

  2. Experimental observations of the microlayer in vapor bubble growth on a heated solid

    Koffman, L.D.; Plesset, M.S.

    1983-01-01

    Experimental measurements of microlayer formation and of the time history of microlayer thickness change have been obtained for nucleate boiling of water and ethanol. These detailed measurements were obtained using laser interometry combined with high-speed cinematography. The measurement technique is discussed in detail with emphasis on the difficulties encountered in interpretation of the fringe patterns. The measurements for water can be reasonably applied to the data of Gunther and Kreith, in which case it is concluded that microlayer evaporate alone cannot account for the increased heat transfer rates observed in highly subcooled nucleate boiling. It appears that microconvection must play at least an equal role

  3. Thermo economic comparison of conventional micro combined heat and power systems with solid oxide fuel cell systems for small scale applications

    Batens, Ellen; Cuellar, Rafael; Marissal, Matthieu

    2013-01-01

    out a thermo economic comparison of a conventional micro combined heat and power systems with solid oxide fuel cell systems. A model to estimate the savings and cost targets for solid oxide fuel cell systems is presented. A comparison between fuel cell technologies in the danish market with “state......Fuel cells have the potential to reduce domestic energy consumption by providing both heat and electricity at the point of use. However, the cost of installing the fuel cell must be sufficiently competitive to be recovered by the savings made over its lifetime. The goal of this paper is to carry...... of the art” traditional heat and power generation technologies currently used in Denmark is considered. The conventional method of covering electrical, heating (e.g. hot water) and cooling (e.g. space cooling) load demands is by purchasing electricity from the electricity network grid and with a fossil fuel...

  4. Possibility of stable quark stars

    Bowers, R.L.; Gleeson, A.M.; Pedigo, R.D.

    1976-08-01

    A recent zero temperature equation of state which contains quark-partons separated from conventional baryons by a phase transition is used to investigate the stability of quark stars. The sensitivity to the input physics is also considered. The conclusions, which are found to be relatively model independent, indicate that a separately identifiable class of stable objects called quark stars does not exist

  5. 30 kV/10 mA solid state anode modulator for gyrotron plasma heating: design issues and results

    Fasel, D.; Lucia, C.; Ganuza, D.; Doyharzabal, I.

    2001-01-01

    Three 30 kV/10 mA solid state pulsed modulators have been delivered to the CRPP in Lausanne, by the company JEMA. Each modulator supplies the anode grid of a triode type gyrotron, used for heating purpose at the third harmonic in the TCV Tokamak. The main parameters of the final design are: the use of solid state technology, a floating output referred to the -80 kV of the gyrotron cathode potential, an output voltage range of -5 to 30 kV, 1 kHz square and sinusoidal modulation, fast switching off to -5 kV (10 μs) and pulsed operation (duty cycle of 1%). After studying and testing a solution based on regulated Mosfet transistors in series, a more stable alternative has been adopted. The final topology consists of a rectifier fed from an insulated 230 V input, a chopper, two inverter steps (for +30 and -5 kV) supplying two diode rectifiers bridges through HV transformers with two switches which commute the load to the positive or negative voltage, connected in series. This article presents the most significant aspects of the design, with special emphasis on the control principle. The final results will be presented in the context of normal operation, supplying a triode gyrotron

  6. The calculation of specific heats for some important solid components in hydrogen production process based on CuCl cycle

    Avsec Jurij

    2014-01-01

    Full Text Available Hydrogen is one of the most promising energy sources of the future enabling direct production of power and heat in fuel cells, hydrogen engines or furnaces with hydrogen burners. One of the last remainder problems in hydrogen technology is how to produce a sufficient amount of cheap hydrogen. One of the best options is large scale thermochemical production of hydrogen in combination with nuclear power plant. copper-chlorine (CuCl cycle is the most promissible thermochemical cycle to produce cheap hydrogen.This paper focuses on a CuCl cycle, and the describes the models how to calculate thermodynamic properties. Unfortunately, for many components in CuCl cycle the thermochemical functions of state have never been measured. This is the reason that we have tried to calculate some very important thermophysical properties. This paper discusses the mathematical model for computing the thermodynamic properties for pure substances and their mixtures such as CuCl, HCl, Cu2OCl2 important in CuCl hydrogen production in their fluid and solid phase with an aid of statistical thermodynamics. For the solid phase, we have developed the mathematical model for the calculation of thermodynamic properties for polyatomic crystals. In this way, we have used Debye functions and Einstein function for acoustical modes and optical modes of vibrations to take into account vibration of atoms. The influence of intermolecular energy we have solved on the basis of Murnaghan equation of state and statistical thermodynamics.

  7. Temperature dependence of the heat capacities in the solid state of 18 mono-, di-, and poly-saccharides

    Hernandez-Segura, Gerardo O.; Campos, Myriam; Costas, Miguel; Torres, Luis A.

    2009-01-01

    The temperature dependence of the heat capacities in solid state C p (T) of 18 mono-, di-, and poly-saccharides has been determined using a power-compensation differential scanning calorimeter. The saccharides were α-D-xylose, D-ribose, 2-deoxy-D-ribose, methyl-β-D-ribose, α-D-glucose, 2-deoxy-D-glucose, α-D-mannose, β-D-fructose, α-D-galactose, methyl-α-D-glucose, sucrose, maltose monohydrate, α-lactose monohydrate, cellobiose, maltotriose, N-acetyl-D-glucosamine, α-cyclodextrin, and β-cyclodextrin. The measurements were carried out at atmospheric pressure and from T = (288.15 to 358.15) K for 15 saccharides and from T = (288.15 to 328.15) K for D-ribose, 2-deoxy-D-ribose, and methyl-β-D-ribose. The present results are compared against literature values both at single temperatures, where most of the data are available, and throughout a range of temperatures, i.e., for C p (T). The predictions of a recently published correlation for organic solids are briefly discussed. By grouping saccharides in subsets, our present results can be used to compare amongst saccharide isomers and to assess the effect of different chemical groups and molecular size

  8. Solar Energy Gain and Space-Heating Energy Supply Analyses for Solid-Wall Dwelling Retrofitted with the Experimentally Achievable U-value of Novel Triple Vacuum Glazing

    Saim Memon

    2017-06-01

    Full Text Available A considerable effort is devoted to devising retrofit solutions for reducing space-heating energy in the domestic sector. Existing UK solid-wall dwellings, which have both heritage values and historic fabric, are being improved but they tend to have meagre thermal performance, partly, due to the heat-loss through glazings. This paper takes comparative analyses approach to envisage space-heating supply required in order to maintain thermal comfort temperatures and attainable solar energy gains to households with the retrofit of an experimentally achievable thermal performance of the fabricated sample of triple vacuum glazing to a UK solid-wall dwelling. 3D dynamic thermal models (timely regimes of heating, occupancy, ventilation and internal heat gains of an externally-insulated solid-wall detached dwelling with a range of existing glazing types along with triple vacuum glazings are modelled. A dramatic decrease of space-heating load and moderate increase of solar gains are resulted with the dwelling of newly achievable triple vacuum glazings (having centre-of-pane U-value of 0.33 Wm-2K-1 compared to conventional glazing types. The space-heating annual cost of single glazed dwellings was minimised to 15.31% (≈USD 90.7 with the retrofit of triple-vacuum glazings. An influence of total heat-loss through the fabric of solid-wall dwelling was analysed with steady-state calculations which indicates a fall of 10.23 % with triple vacuum glazings compared to single glazings.

  9. Studies report: methods for the evaluation and the prevention of accidental risks (DRA 35 - report Ω 11). Knowledge of solid fuels self-heating

    2005-02-01

    The aim of this document is to present a synthesis of the knowledge on risks bond to auto-heating phenomena which occur in solid fuels storage. It analyzes the role of some factors on the heating, and more specially the mass, temperature, oxygen content of the atmosphere and humidity. It presents a general methodology of risks evaluation and measures on the risks detection and prevention. (A.L.B.)

  10. Experimental study of the evaporation and expansion of a solid pellet in a plasma heated by an electron beam

    Akent'ev, R.Yu.; Arzhannikov, A.V.; Astrelin, V.T.; Burdakov, A.V.; Ivanov, I.A.; Kojdan, V.S.; Mekler, K.I.; Polosatkin, S.V.; Postupaev, V.V.; Rovenskikh, A.F.; Sinitskij, S.L.

    2004-01-01

    The results of experiments on the solid pellets injection into the plasma, heated by an electron beam at the GOL-3 facility, are presented. The polyethylene pellets with the mass of 0.1-1 mg and lithium deuteride pellets with the mass of 0.02-0.5 mg were used. The dense plasma bunch, scattering at first spherically, is formed during several microseconds after the beginning of the electron beam injection into the plasma. Thereafter the bunch periphery is heated and becomes magnetized. Further there takes place the expansion of the dense plasma along the magnetic field on the order of 300 km/s. Comparison of the observed values with the calculations by the hydrodynamic model indicates, that for explaining such a rate of the bunch expansion the density of the total energy, falling on the pellet, should be ∼1 kJ/cm 2 . This value exceeds the corresponding value for the main plasma, i.e. there is observed the energy concentration across the magnetic field into the dense bunch of the evaporated macroparticle [ru

  11. Oxygen control in solid fuel fired heating systems with zirconium oxide cells. Iltstyring af fastbraendselsfyrede anlaeg med zirkoniumoxidcelle

    Zielke, U.

    1988-10-15

    During the heating season 87-88 the Jutland Technological Institute has carried out investigations of the zirconium oxygen meters of solid fuel heating units. The aim was to investigate whether the combustion of inflammable flue gas components on the surface of the oxygen meter cell is of any importance to the running and emissions of the units. The used zirconium oxide oxygen meters normally measure lower concentrations of oxygen as the paramagnetic comparator of the laboratory. The relative deviation is lowest at coal fired units (5.5% and highest at straw fired units (20%)). At several units there is a clear tendency towards increasing development of CO at an increasing surplus of air. Because of too large a surplus of air, and in consequence of this the formation of CO, the chimney waste of the units is increased by up to 6%. Both the surplus of air and the concentration of CO have been included as long term average values. Especially at the straw fired units, periodically very high concentrations of non-inflammable flue gas components can be found, resulting in an undesirable influence on the environment. The development of improved control systems and regulation equipment is recommended.

  12. Research into properties of dust from domestic central heating boiler fired with coal and solid biofuels

    Konieczyński Jan

    2017-06-01

    Full Text Available The aim of this research was to assess the content and composition of the pollutants emitted by domestic central heating boilers equipped with an automatic underfeed fuel delivery system for the combustion chamber. The comparative research was conducted. It concerned fuel properties, flue gas parameters, contents of dust (fl y ash and gaseous substances polluting the air in the flue gases emitted from a domestic CH boiler burning bituminous coal, pellets from coniferous wood, cereal straw, miscanthus, and sunflower husks, coniferous tree bark, and oats and barley grain. The emission factors for dust and gaseous air pollutants were established as they are helpful to assess the contribution of such boilers in the atmospheric air pollution. When assessing the researched boiler, it was found out that despite the development in design and construction, flue gases contained fly ash with a significant EC content, which affected the air quality.

  13. Geothermal heat from solid rock - increased energy extraction through hydraulic pressurizing of drill wells

    Ramstad, Randi Kalskin; Hilmo, Bernt Olav; Skarphagen, Helge

    2005-01-01

    New equipment for hydraulic pressurizing, a double collar of the type FrakPak - AIP 410-550, is developed by the Broennteknologi AS. The equipment is tested in the laboratory and in the field at Lade in Trondheim. By the construction of two pilot plants for geothermal heat at Bryn and on the previous grounds of the energy company in Asker and Baerum (EAB) extensive studies connected to hydraulic pressurizing are carried out both with water and sand injection. The geothermal heat plants at Bryn and AEB were supposed to be based on pumped ground water from rock wells where increased effect was obtained through pumping up, returning and circulating the water. The aim of the study was to test and develop the methods for hydraulic pressurizing both with water and sand injection, document the effect of the various types of pressurizing as well as mapping the hydro- and rock geological conditions for this type of geothermal heat plants. In addition to stimulating 10 drill holes with hydraulic pressurizing with water and sand injection, the studies have carried out test pumping, water sampling, geophysical logging, measurements of alterations in the terrain, current and rock strain measurements and geothermal response tests. Furthermore an efficacy test and a theoretical model of the energy potential of the plants are carried out. The results from the pilot plant at Bryn show that the drill hole capacities are significantly increased both through hydraulic pressurizing with water and sand injection. There seems to be a greater need for sand as ''prepping agent'' or distance maker in cracks with high pressure resistance than in cracks with lower resistance. The grain size of the sand should be adapted to the resistance pressure and injection of coarser sand is recommended in cracks with lower resistance pressure. The rock strength and strain conditions determine the successes of hydraulic pressurizing at the reopening of existing or opening of new faults. Test pumping was

  14. Heavy quark spectroscopy

    Rosner, J.L.

    1985-10-01

    New experimental and theoretical developments in heavy quark spectroscopy are reviewed. From studies of J/psi decays, the eta' is found to have some ''glue'' or other inert component, while the iota (a glueball candidate) probably contains some quarks as well. The xi(2.2) persists in new Mark III data, but is not seen by the DM2 collaboration. The production of charmonium states by anti pp reactions is reviewed. First evidence for a P- wave charmed meson, D(2420), has been presented by the ARGUS group. Radiative UPSILON decay studies fail to confirm the zeta(8.3) and begin to place useful limits on Higgs bosons. First results from an experiment at Fermilab on low-background hadronic production of UPSILON states are shown. Accurate measurements of chi/sub b/(1P) masses by the ARGUS collaboration are noted, and interpreted as favoring scalar quark confinement. Studies of t and other heavy quarks will probe the q anti q interaction below 0.05 fm, are likely to be strongly affected by t anti t-Z interference, and can provide varied information on Higgs bosons. 144 refs., 21 figs

  15. Top quark theory

    2012-10-04

    Oct 4, 2012 ... The theoretical aspects of a number of top quark properties such as ... to the quadratic divergences of the Higgs self-energy, while yet, ..... given in the literature, each with the aim of recovering a well-behaved expansion in αs.

  16. Top quark properties

    eter for the tests of the electroweak theory, since radiative corrections to many ... The uncertainty due to jet energy scale (JES) is the dominating systematic .... In the Standard Model, the charge of the top quark is predicted to be that of a normal up- ..... non-negative and f+ + f0 < 1, and the star marks the expectation from the ...

  17. Heavy quarks photoproduction

    Cacciari, M.

    1996-08-01

    The state of the art of the theoretical calculations for heavy quarks photoproduction is reviewed. The full next-to-leading order calculation and two possible resummations, the high energy one for total cross sections and the large p T one for differential cross sections, are described. (orig.)

  18. Top quark mass measurement

    Maki, Tuula; Helsinki Inst. of Phys.; Helsinki U. of Tech.

    2008-01-01

    The top quark is the heaviest elementary particle. Its mass is one of the fundamental parameters of the standard model of particle physics, and an important input to precision electroweak tests. This thesis describes three measurements of the top-quark mass in the dilepton decay channel. The dilepton events have two neutrinos in the final state; neutrinos are weakly interacting particles that cannot be detected with a multipurpose experiment. Therefore, the signal of dilepton events consists of a large amount of missing energy and momentum carried off by the neutrinos. The top-quark mass is reconstructed for each event by assuming an additional constraint from a top mass independent distribution. Template distributions are constructed from simulated samples of signal and background events, and parameterized to form continuous probability density functions. The final top-quark mass is derived using a likelihood fit to compare the reconstructed top mass distribution from data to the parameterized templates. One of the analyses uses a novel technique to add top mass information from the observed number of events by including a cross-section-constraint in the likelihood function. All measurements use data samples collected by the CDF II detector

  19. Small quarks make big nuggets

    Deligeorges, S.

    1985-01-01

    After a brief recall on the classification of subatomic particles, this paper deals with quark nuggets, particle with more than three quarks, a big bag, which is called ''nuclearite''. Neutron stars, in fact, are big sacks of quarks, gigantic nuggets. Now, physicists try to calculate which type of nuggets of strange quark matter is stable, what has been the influence of quark nuggets on the primordial nucleosynthesis. At the present time, one says that if these ''nuggets'' exist, and in a large proportion, they may be candidates for the missing mass [fr

  20. Performance analysis of a solar-powered solid state heat engine for electricity generation

    Long, Rui; Li, Baode; Liu, Zhichun; Liu, Wei

    2015-01-01

    A hybrid system consisting of a CPC (compound parabolic collector) system, a SOE (solid oxide electrolyzer) system and a PEMFC (proton exchange membrane fuel cell) system was proposed to harvest solar energy. And a sensitivity analysis was conducted to evaluate the system performance. The impacts of operating temperatures of the SOE and PEMFC system, and the direct irradiation intensity of the sun on the performance characteristics were systematically analyzed. Results revealed that there exists an optimal SOE operating temperature leading to the maximum power output and maximum electrical efficiency simultaneously. Larger operating temperature of the PEMFC resulted in larger power output and higher efficiency. There also existed optimal direct irradiation intensities leading to the maximum power output and maximum electrical efficiency. Furthermore, the performance of the proposed solar energy harvesting system for practical use in real-life was also simulated. This may serve a clean technology for electricity generation. - Highlights: • A hybrid system consisting of CPC, SOE and PEMFC is proposed to harvest solar energy. • A sensitivity analysis was conducted to evaluate the system performance. • Power output and electrical efficiency have maximum values. • Performance of the proposed hybrid system for practical use was simulated.

  1. Heavy quarks - experimental

    Hollebeek, R.

    1990-01-01

    The purpose of these lectures, given at the 1989 SLAC Summer School, was to discuss the experimental aspects of heavy quark production. A companion set of lectures on the theoretical point of view were to be given by Keith Ellis. An experimentalist should gather together the measurements which have been made by various groups, compare, contrast and tabulate them, and if possible point out the ways in which these measurements confirm or contradict current theories. Here the authors has tried to do this, although the reader who expects to find here the latest of all experimental measurements should probably be forewarned that the field is moving extremely rapidly. In some cases, he has added and updated materials where crucial new information became available after or during the summer of 1989, but not in all cases. He has concentrated on trying to select those measurements which are at the moment most crucial in refining our understanding of heavy quarks as opposed to those which merely measure things which are perhaps too complicated to be enlightening at the moment. While theorists worry primarily about production mechanisms, cross sections, QCD corrections, and to some extent about signatures, the experimentalist must determine which measurements he is interested in making, and which signatures for heavy quark production are realistic and likely to produce results which will shed some new light on the underlying production model without undo theoretical complications. Experimentalists also need to evaluate the available experimental equipment, both machines and detectors to find the best way to investigate the properties of heavy quarks. In many cases, the things which we would like to measure are severely restricted by what we can measure. Nevertheless, many properties of heavy quark production and decay can be measured, and the results have already taught us much about the weak interactions and QCD

  2. Coefficient of solid-gas heat transfer in particle fixed bed; Coeficiente de transferencia de calor gas-solido em leito fixo de particulas

    Fernandes Filho, Francisco

    1991-03-01

    The work presents a study on heat transfer between gas and solid phases for fixed beds in the absence of mass transfer and chemical reactions. Mathematical models presented in the literature were analyzed concerning to the assumptions made on axial dispersion in the fluid phase and interparticle thermal conductivity. Heat transfer coefficients and their dependency on flow conditions, particles and packed bed characteristics were experimentally determined through the solution of the previous mathematical models. Pressure drop behaviour for the packed beds used for the heat transfer study was also included. (author) 32 refs., 12 figs.

  3. Quark effects in nuclear physics

    Miller, G.A.

    1983-01-01

    A phenomenological approach which enables the size of quark effects in various nuclear processes is discussed. The principle of conservation of probability provides significant constraints on six quark wave functions. Using this approach, it is found that the low-energy proton-proton weak interaction can be explained in terms of W and Z boson exchanges between quarks. That the value of the asymptotic ratio of D to S state wave functions is influenced (at the 5% level) by quark effects, is another result of our approach. We have not discovered a nuclear effect that can be uniquely explained by quark-quark interactions. However it does seem that quark physics is very relevant for nuclear physics. 52 references

  4. 100 kV solid-state switch for fusion heating systems

    Beaumont, B.; Bertrand, E.; Brugnetti, R.; Chatroux, D.; Kazarian, F.; Milly, R.; Prou, M.; Rigole, H.

    2005-01-01

    Power switching in RF heating systems is a delicate function as it is often linked to high power tube protection. In most RF systems, the end stage power tube is fed by a high voltage power supply (HVPS), which connection to the tube has to be interrupted in case of arc suspicion. The amount of energy that is allowable to be dissipated in the arc is in the range of 10-50 J, to limit the degradations observed on the tube structures. The protection function is usually performed by a crowbar. Furthermore, the HVPS is often shared by several power tubes, and the loss of all the power from the group of tubes is to be avoided to minimize the perturbation on the plasma experiment. A description of a 40 kV thyristor based crowbar and a 100 kV, 25 A MOSFET switch is given, as well as the contours of the existing components for high power switching applications. By combining small components, such as thyristors or MOSFET, in matrix, highly compact and reliable units have been built and implemented in Tore Supra RF systems

  5. Comparison of ANN (MLP), ANFIS, SVM, and RF models for the online classification of heating value of burning municipal solid waste in circulating fluidized bed incinerators.

    You, Haihui; Ma, Zengyi; Tang, Yijun; Wang, Yuelan; Yan, Jianhua; Ni, Mingjiang; Cen, Kefa; Huang, Qunxing

    2017-10-01

    The heating values, particularly lower heating values of burning municipal solid waste are critically important parameters in operating circulating fluidized bed incineration systems. However, the heating values change widely and frequently, while there is no reliable real-time instrument to measure heating values in the process of incinerating municipal solid waste. A rapid, cost-effective, and comparative methodology was proposed to evaluate the heating values of burning MSW online based on prior knowledge, expert experience, and data-mining techniques. First, selecting the input variables of the model by analyzing the operational mechanism of circulating fluidized bed incinerators, and the corresponding heating value was classified into one of nine fuzzy expressions according to expert advice. Development of prediction models by employing four different nonlinear models was undertaken, including a multilayer perceptron neural network, a support vector machine, an adaptive neuro-fuzzy inference system, and a random forest; a series of optimization schemes were implemented simultaneously in order to improve the performance of each model. Finally, a comprehensive comparison study was carried out to evaluate the performance of the models. Results indicate that the adaptive neuro-fuzzy inference system model outperforms the other three models, with the random forest model performing second-best, and the multilayer perceptron model performing at the worst level. A model with sufficient accuracy would contribute adequately to the control of circulating fluidized bed incinerator operation and provide reliable heating value signals for an automatic combustion control system. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Energetic and Exergetic Analysis of a Heat Exchanger Integrated in a Solid Biomass-Fuelled Micro-CHP System with an Ericsson Engine

    Marie Creyx

    2016-04-01

    Full Text Available A specific heat exchanger has been developed to transfer heat from flue gas to the working fluid (hot air of the Ericsson engine of a solid biomass-fuelled micro combined heat and power (CHP. In this paper, the theoretical and experimental energetic analyses of this heat exchanger are compared. The experimental performances are described considering energetic and exergetic parameters, in particular the effectiveness on both hot and cold sides. A new exergetic parameter called the exergetic effectiveness is introduced, which allows a comparison between the real and the ideal heat exchanger considering the Second Law of Thermodynamics. A global analysis of exergetic fluxes in the whole micro-CHP system is presented, showing the repartition of the exergy destruction among the components.

  7. A second-order coupled immersed boundary-SAMR construction for chemically reacting flow over a heat-conducting Cartesian grid-conforming solid

    Kedia, Kushal S.; Safta, Cosmin; Ray, Jaideep; Najm, Habib N.; Ghoniem, Ahmed F.

    2014-01-01

    In this paper, we present a second-order numerical method for simulations of reacting flow around heat-conducting immersed solid objects. The method is coupled with a block-structured adaptive mesh refinement (SAMR) framework and a low-Mach number operator-split projection algorithm. A "buffer zone" methodology is introduced to impose the solid-fluid boundary conditions such that the solver uses symmetric derivatives and interpolation stencils throughout the interior of the numerical domain; irrespective of whether it describes fluid or solid cells. Solid cells are tracked using a binary marker function. The no-slip velocity boundary condition at the immersed wall is imposed using the staggered mesh. Near the immersed solid boundary, single-sided buffer zones (inside the solid) are created to resolve the species discontinuities, and dual buffer zones (inside and outside the solid) are created to capture the temperature gradient discontinuities. The development discussed in this paper is limited to a two-dimensional Cartesian grid-conforming solid. We validate the code using benchmark simulations documented in the literature. We also demonstrate the overall second-order convergence of our numerical method. To demonstrate its capability, a reacting flow simulation of a methane/air premixed flame stabilized on a channel-confined bluff-body using a detailed chemical kinetics model is discussed. © 2014 Elsevier Inc.

  8. A second-order coupled immersed boundary-SAMR construction for chemically reacting flow over a heat-conducting Cartesian grid-conforming solid

    Kedia, Kushal S.

    2014-09-01

    In this paper, we present a second-order numerical method for simulations of reacting flow around heat-conducting immersed solid objects. The method is coupled with a block-structured adaptive mesh refinement (SAMR) framework and a low-Mach number operator-split projection algorithm. A "buffer zone" methodology is introduced to impose the solid-fluid boundary conditions such that the solver uses symmetric derivatives and interpolation stencils throughout the interior of the numerical domain; irrespective of whether it describes fluid or solid cells. Solid cells are tracked using a binary marker function. The no-slip velocity boundary condition at the immersed wall is imposed using the staggered mesh. Near the immersed solid boundary, single-sided buffer zones (inside the solid) are created to resolve the species discontinuities, and dual buffer zones (inside and outside the solid) are created to capture the temperature gradient discontinuities. The development discussed in this paper is limited to a two-dimensional Cartesian grid-conforming solid. We validate the code using benchmark simulations documented in the literature. We also demonstrate the overall second-order convergence of our numerical method. To demonstrate its capability, a reacting flow simulation of a methane/air premixed flame stabilized on a channel-confined bluff-body using a detailed chemical kinetics model is discussed. © 2014 Elsevier Inc.

  9. The small-scale production of hydrogen, with the co-production of electricity and district heat, by means of the gasification of municipal solid waste

    Hognert, Johannes; Nilsson, Lars

    2016-01-01

    Highlights: • Outline of a process for handling municipal solid waste potentially leading to reduced use of fossil transportation fuels. • The integration of waste gasification into a district heat plant leads to excellent energy efficiency. • Analysis based on actual production data from a district heat plant over the period of one year. • Simulation of a plant with productions of heat, power and gaseous hydrogen. - Abstract: Reducing the use of fossil fuels and increasing the recycling of waste are two important challenges for a sustainable society. Fossil fuels contribute to global warming whilst waste causes the pollution of land, water and air. Alternative fuels and innovative waste management systems are needed to address these issues. In this study a gasification process, fuelled with municipal solid waste, was assumed to be integrated into a heat plant to produce hydrogen, electricity and district heat. A whole system, which includes a gasification reactor, heat plant, steam cycle, pressure swing adsorption, gas turbine and compressors was modelled in Microsoft Excel and an energy balance of the system was solved. Data from the scientific literature were used when setting up the heat and mass balances of the gasification process as well as for assessment of the composition of the syngas. The allocation of energy of the products obtained in the process is 29% hydrogen, 26% electricity and 45% district heat. A significant result of the study is the high energy efficiency (88%) during the cold period of the year when the produced heat in the system is utilized for district heat. The system also shows a competitive energy efficiency (56.5%) all year round.

  10. Dilepton production from quark gluon plasma using non-equilibrium thermodynamics

    Sinha, B.

    1984-01-01

    The importance of the approach phase to the thermodynamic equilibrium has been investigated for dilepton production from quark-gluon plasma - an effective temperature for the quarks as Brounian particle in a heat bath of gluons has been suggested. The spectrum for low invariant mass is, as a consequence, sharper

  11. Impurity transport studies by means of tracer-encapsulated solid pellet injection in neutral beam heated plasmas on LHD

    Tamura, N; Sudo, S; Khlopenkov, K V; Kato, S; Sergeev, V Yu; Muto, S; Sato, K; Funaba, H; Tanaka, K; Tokuzawa, T; Yamada, I; Narihara, K; Nakamura, Y; Kawahata, K; Ohyabu, N; Motojima, O

    2003-01-01

    The quantitative properties of impurity transport in large helical device (LHD) plasmas heated by neutral beam injection have been investigated by means of tracer-encapsulated solid pellet (TESPEL) injection. In the case of a titanium (Ti) tracer, the behaviour of the emission lines from the highly ionized Ti impurity, Ti Kα(E He-like ∼ 4.7 keV) and Ti XIX (λ = 16.959 nm), has been observed clearly by a soft x-ray pulse height analyzer and a vacuum ultraviolet spectrometer, respectively. A fairly longer decay time of the Ti Kα emission lines is obtained above the value of a line-averaged electron density, 3.0x10 19 m -3 . The dependence of the behaviour of the Ti tracer impurity on the line-averaged electron density below the value of that, 3.5x10 19 m -3 is in qualitative agreement with the characteristics obtained from the observation of the behaviour of an intrinsic metallic impurity in neutral beam heated plasmas on LHD. In order to estimate the properties of the Ti impurity transport quantitatively, the one-dimensional impurity transport code, MIST has been used. As a result of the transport analysis with the MIST code, even an small inward convection should be necessary to account for the experimental results with the value of the line-averaged electron density, 3.5x10 19 m -3 . In order to examine the experimentally obtained transport coefficients, neoclassical analysis with respect to the radial impurity flux has been performed. The inferred rise of the inward convection cannot be explained solely by neoclassical impurity transport. Therefore, in order to account for the inward convection, the effect of a radial electric field and/or some other effect must be taken into account additionally

  12. Heat and Mass Transfer during Solid-Liquid Phase Transition of n-Alkanes in the C{sub 16} to C{sub 19} Range

    Holmen, Rune

    2002-07-01

    The main goal of this project has been to study heat and mass transfer during solid-liquid phase transition of n-alkanes in the in the C{sub 16} to C{sub 19} range. Phase transitions of both mixtures and pure components have been investigated. All experiments and simulations have been performed without any convection. Thermal conductivities have been determined at the melting point for solid and liquid unbranched alkanes ranging from C{sub 16} to C{sub 19}. An assessment of the error of the method has been performed. The measurements of solid conductivities are in accordance with measurements reported previously and confirm the applicability of the method. Liquid conductivities are higher than extrapolated values from the literature. The enhanced conductivity is believed to be caused by structural changes close to the melting point which is not taken into account when extrapolating values from the literature. Experiments have been performed for the purpose of investigating the freezing of mixtures of n-alkanes in the C{sub 16}-C{sub 19} range. The positions of the solid-liquid interfaces have been measured as freezing occurred. Calculations of the ratio of liquid and solid conductivities show that the solid structure of mixtures of the investigated n-alkanes is predominantly in a rotator structure at the temperatures investigated. There are indications of a transformation into an orthorhombic structure at lower temperatures. The temperatures on the solid-liquid interface have been measured, and compared with calculated values from chapter 4. The temperature of the interface is represented better by the measured interfacial temperatures than by the calculated interfacial temperatures. The experimental results indicate that the diffusion of heat is the limiting mechanism of phase transition. This result in a homogeneous liquid composition. A numerical model has been developed in order to simulate the experimental freezing of mixtures. The model represents the results

  13. Qualitative quark confinement

    Jackson, T.L.

    1976-01-01

    The infrared limit in asymptotically free non-abelian gauge theories using recently developed non-perturbative methods which allow derivation of zero momentum theorems for Green's functions and vertices is described. These low-energy theorems are compared to the infrared behavior predicted from the renormalization group equation when the existence of an infrared fixed point is assumed. A set of objects is exhibited whose low energy theorems violate the scaling behavior predicted by the renormalization group. This shows that the assumed fixed point cannot exist and that in the Landau gauge the effective charge becomes infinite in the infrared. Qualitatively this implies that as an attempt is made to separate elementary quanta the interaction between the quanta becomes arbitrarily strong. This indicates at least that the theories studied are capable of color confinement. Results are true only for theories with large numbers of quarks. This opens the possibility that large numbers of quarks are actually necessary for confinement

  14. Nucleon quark distributions in a covariant quark-diquark model

    Cloet, I.C. [Special Research Centre for the Subatomic Structure of Matter and Department of Physics and Mathematical Physics, University of Adelaide, SA 5005 (Australia) and Jefferson Lab, 12000 Jefferson Avenue, Newport News, VA 23606 (United States)]. E-mail: icloet@physics.adelaide.edu.au; Bentz, W. [Department of Physics, School of Science, Tokai University, Hiratsuka-shi, Kanagawa 259-1292 (Japan)]. E-mail: bentz@keyaki.cc.u-tokai.ac.jp; Thomas, A.W. [Jefferson Lab, 12000 Jefferson Avenue, Newport News, VA 23606 (United States)]. E-mail: awthomas@jlab.org

    2005-08-18

    Spin-dependent and spin-independent quark light-cone momentum distributions and structure functions are calculated for the nucleon. We utilize a modified Nambu-Jona-Lasinio model in which confinement is simulated by eliminating unphysical thresholds for nucleon decay into quarks. The nucleon bound state is obtained by solving the Faddeev equation in the quark-diquark approximation, where both scalar and axial-vector diquark channels are included. We find excellent agreement between our model results and empirical data.

  15. Prediction of new Quarks, Generations & low Mass Quarks

    Lach, Theodore

    2003-04-01

    The CBM (model) of the nucleus has resulted in the prediction of two new quarks, an "up" quark of mass 237.31 MeV/c2 and a "dn" quark of mass 42.392 MeV/c2. These two new predicted quarks helped to determine that the masses of the quarks and leptons are all related by a geometric progression relationship. The mass of each quark or lepton is just the "geometric mean" of two related elementary particles, either in the same generation or in the same family. This numerology predicts the following masses for the electron family: 0.511000 (electron), 7.74 (predicted), 117.3, 1778.4 (tau), 26950.1 MeV. The geometric ratio of this progression is 15.154 (e to the power e). The mass of the tau in this theory agrees very well with accepted values. This theory suggests that all the "dn like" quarks have a mass of just 10X multiples of 4.24 MeV (the mass of the "d" quark). The first 3 "up like" quark masses are 38, 237.31 and 1500 MeV. This theory also predicts a new heavy generation with a lepton mass of 27 GeV, a "dn like" quark of 42.4 GeV, and an "up like" quark of 65 GeV. Significant evidence already exists for the existence of these new quarks, and lepton. Ref. Masses of the Sub-Nuclear Particles, nucl-th/ 0008026, @ http://xxx.lanl.gov. Infinite Energy, Vol 5, issue 30.

  16. Quark-Gluon Plasma

    1990-01-01

    This volume contains 14 review articles on the theory and phenomenology of the creation and diagnosis of quark-gluon plasma. They are written by active investigators of in the various research topics, which range from the QCD foundation through transport theory and thermalization models to the examination of possible signatures. The monograph should be useful not only to the experienced researchers in the subject but also to newcomers.

  17. Quarks, culture, combogenesis

    Wood, Barry

    2018-01-01

    The value of Tyler Volk’s Quarks to Culture is evident when the book is placed against popular histories of the universe, dozens of which have provided evidence for an immense cosmic past. But such histories are often anecdotal, like early British histories of the kings of England. Unlike these works, Volk artfully presents the case for structural continuity and systematic cre­ativity across 13.8 billion years of cosmic history.

  18. Quarks and partons

    Paschos, E.A.

    1976-08-01

    The quark parton model describes the inclusive electro- and neutrino production data if a clear distinction is made between reactions which take place at high and at low energies. For the low energy region the classical view of six structure functions of the proton is still adequate. For the high energy region models can be constructed which are consistent with the experimental data. (BJ) [de

  19. The conventional quark picture

    Dalitz, R.H.

    1976-01-01

    For baryons, mesons and deep inelastic phenomena the ideas and the problems of the conventional quark picture are pointed out. All observed baryons fit in three SU(3)-multiplets which cluster into larger SU(6)-multiplets. No mesons are known which have quantum numbers inconsistent with belonging to a SU(3) nonet or octet. The deep inelastic phenomena are described in terms of six structure functions of the proton. (BJ) [de

  20. Quark gluon plasma

    Nayak, Tapan; Sarkar, Sourav

    2014-01-01

    At extremely high temperatures and densities, protons and neutrons may dissolve into a "soup" of quarks and gluons, called the Quark-Gluon Plasma (QGP). For a few microseconds, shortly after the Big Bang, the Universe was filled with the QGP matter. The search and study of Quark-Gluon Plasma (QGP) is one of the most fundamental research topics of our times. The QGP matter has been probed by colliding heavy ions at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory, New York and the Large Hadron Collider at CERN, Geneva. By colliding heavy-ions at a speed close to that of light, scientists aim to obtain - albeit over a tiny volume of the size of a nucleus and for an infinitesimally short instant - a QGP state. This QGP state can be observed by dedicated experiments, as it reverts to hadronic matter through expansion and cooling. This volume presents some of the current theoretical and experimental understandings in the field of QGP.

  1. The quark gluon plasma

    Granier de Cassagnac, R.

    2010-01-01

    The quark-gluon plasma (QGP) is a state of matter in which the universe was expected to be a few micro-seconds after the big-bang. Violent collisions of heavy ions are supposed to re-create this state in particle accelerators. Numerous signatures of this fugacious state have already been observed at the RHIC (relativistic heavy ion collider). The first evidence of the violence of collisions is the number of generated particles: about 6000 per collision, mostly hadrons. This figure seems high but in fact is less than theoretically expected and is the first sign of the formation of a QGP that saturates the density of gluons. Another sign, observed at the RHIC is the damping of the particle jets that are produced in the collision. This damping is consistent with the crossing of a medium whose density is so high that it can not be made of hadrons but of partons. In the RHIC experiments the collective behaviour of quarks and gluons shows that they are strongly interacting with one another. This fact supports the idea that the QGP is more a perfect liquid rather than an ideal gas in which quarks and gluons move freely. (A.C.)

  2. Fields, symmetries, and quarks

    Mosel, U.

    1989-01-01

    'Fields, symmetries, and quarks' covers elements of quantum field theory, symmetries, gauge field theories and phenomenological descriptions of hadrons, with special emphasis on topics relevant to nuclear physics. It is aimed at nuclear physicists in general and at scientists who need a working knowledge of field theory, symmetry principles of elementary particles and their interactions and the quark structure of hadrons. The book starts out with an elementary introduction into classical field theory and its quantization. As gauge field theories require a working knowledge of global symmetries in field theories this topic is then discussed in detail. The following part is concerned with the general structure of gauge field theories and contains a thorough discussion of the still less widely known features of Non-Abelian gauge field theories. Quantum Chromodynamics (QCD), which is important for the understanding of hadronic matter, is discussed in the next section together with the quark compositions of hadrons. The last two chapters give a detailed discussion of phenomenological bag-models. The MIT bag is discussed, so that all theoretical calculations can be followed step by step. Since in all other bag-models the calculational methods and steps are essentially identical, this chapter should enable the reader to actually perform such calculations unaided. A last chapter finally discusses the topological bag-models which have become quite popular over the last few years. (orig.)

  3. Mathematical Analysis of the Solidification Behavior of Plain Steel Based on Solute- and Heat-Transfer Equations in the Liquid-Solid Zone

    Fujimura, Toshio; Takeshita, Kunimasa; Suzuki, Ryosuke O.

    2018-04-01

    An analytical approximate solution to non-linear solute- and heat-transfer equations in the unsteady-state mushy zone of Fe-C plain steel has been obtained, assuming a linear relationship between the solid fraction and the temperature of the mushy zone. The heat transfer equations for both the solid and liquid zone along with the boundary conditions have been linked with the equations to solve the whole equations. The model predictions ( e.g., the solidification constants and the effective partition ratio) agree with the generally accepted values and with a separately performed numerical analysis. The solidus temperature predicted by the model is in the intermediate range of the reported formulas. The model and Neuman's solution are consistent in the low carbon range. A conventional numerical heat analysis ( i.e., an equivalent specific heat method using the solidus temperature predicted by the model) is consistent with the model predictions for Fe-C plain steels. The model presented herein simplifies the computations to solve the solute- and heat-transfer simultaneous equations while searching for a solidus temperature as a part of the solution. Thus, this model can reduce the complexity of analyses considering the heat- and solute-transfer phenomena in the mushy zone.

  4. Transversity quark distributions in a covariant quark-diquark model

    Cloet, I.C. [Physics Division, Argonne National Laboratory, Argonne, IL 60439-4843 (United States)], E-mail: icloet@anl.gov; Bentz, W. [Department of Physics, School of Science, Tokai University, Hiratsuka-shi, Kanagawa 259-1292 (Japan)], E-mail: bentz@keyaki.cc.u-tokai.ac.jp; Thomas, A.W. [Jefferson Lab, 12000 Jefferson Avenue, Newport News, VA 23606 (United States); College of William and Mary, Williamsburg, VA 23187 (United States)], E-mail: awthomas@jlab.org

    2008-01-17

    Transversity quark light-cone momentum distributions are calculated for the nucleon. We utilize a modified Nambu-Jona-Lasinio model in which confinement is simulated by eliminating unphysical thresholds for nucleon decay into quarks. The nucleon bound state is obtained by solving the relativistic Faddeev equation in the quark-diquark approximation, where both scalar and axial-vector diquark channels are included. Particular attention is paid to comparing our results with the recent experimental extraction of the transversity distributions by Anselmino et al. We also compare our transversity results with earlier spin-independent and helicity quark distributions calculated in the same approach.

  5. Quark core stars, quark stars and strange stars

    Grassi, F.

    1988-01-01

    A recent one flavor quark matter equation of state is generalized to several flavors. It is shown that quarks undergo a first order phase transition. In addition, this equation of state depends on just one parameter in the two flavor case, two parameters in the three flavor case, and these parameters are constrained by phenomenology. This equation of state is then applied to the hadron-quark transition in neutron stars and the determination of quark star stability, the investigation of strange matter stability and possible strange star existence. 43 refs., 6 figs

  6. Top quark pair production and top quark properties at CDF

    Moon, Chang-Seong [INFN, Pisa

    2016-06-02

    We present the most recent measurements of top quark pairs production and top quark properties in proton-antiproton collisions with center-of-mass energy of 1.96 TeV using CDF II detector at the Tevatron. The combination of top pair production cross section measurements and the direct measurement of top quark width are reported. The test of Standard Model predictions for top quark decaying into $b$-quarks, performed by measuring the ratio $R$ between the top quark branching fraction to $b$-quark and the branching fraction to any type of down quark is shown. The extraction of the CKM matrix element $|V_{tb}|$ from the ratio $R$ is discussed. We also present the latest measurements on the forward-backward asymmetry ($A_{FB}$) in top anti-top quark production. With the full CDF Run II data set, the measurements are performed in top anti-top decaying to final states that contain one or two charged leptons (electrons or muons). In addition, we combine the results of the leptonic forward-backward asymmetry in $t\\bar t$ system between the two final states. All the results show deviations from the next-to-leading order (NLO) standard model (SM) calculation.

  7. The impact of household cooking and heating with solid fuels on ambient PM2.5 in peri-urban Beijing

    Liao, Jiawen; Zimmermann Jin, Anna; Chafe, Zoë A.; Pillarisetti, Ajay; Yu, Tao; Shan, Ming; Yang, Xudong; Li, Haixi; Liu, Guangqing; Smith, Kirk R.

    2017-09-01

    Household cooking and space heating with biomass and coal have adverse impacts on both indoor and outdoor air quality and are associated with a significant health burden. Though household heating with biomass and coal is common in northern China, the contribution of space heating to ambient air pollution is not well studied. We investigated the impact of space heating on ambient air pollution in a village 40 km southwest of central Beijing during the winter heating season, from January to March 2013. Ambient PM2.5 concentrations and meteorological conditions were measured continuously at rooftop sites in the village during two winter months in 2013. The use of coal- and biomass-burning cookstoves and space heating devices was measured over time with Stove Use Monitors (SUMs) in 33 households and was coupled with fuel consumption data from household surveys to estimate hourly household PM2.5 emissions from cooking and space heating over the same period. We developed a multivariate linear regression model to assess the relationship between household PM2.5 emissions and the hourly average ambient PM2.5 concentration, and a time series autoregressive integrated moving average (ARIMA) regression model to account for autocorrelation. During the heating season, the average hourly ambient PM2.5 concentration was 139 ± 107 μg/m3 (mean ± SD) with strong autocorrelation in hourly concentration. The average primary PM2.5 emission per hour from village household space heating was 0.736 ± 0.138 kg/hour. The linear multivariate regression model indicated that during the heating season - after adjusting for meteorological effects - 39% (95% CI: 26%, 54%) of hourly averaged ambient PM2.5 was associated with household space heating emissions from the previous hour. Our study suggests that a comprehensive pollution control strategy for northern China, including Beijing, should address uncontrolled emissions from household solid fuel combustion in surrounding areas, particularly

  8. A new parametric equation of state and quark stars

    Na Xuesen; Xu Renxin

    2011-01-01

    It is still a matter of debate to understand the equation of state of cold matter with supra-nuclear density in compact stars because of unknown non-perturbative strong interaction between quarks. Nevertheless, it is speculated from an astrophysical view point that quark clusters could form in cold quark matter due to strong coupling at realistic baryon densities. Although it is hard to calculate this conjectured matter from first principles, one can expect that the inter-cluster interaction will share some general features with the nucleon- nucleon interaction successfully depicted by various models. We adopt a two-Gaussian component soft-core potential with these general features and show that quark clusters can form stable simple cubic crystal structure if we assume that the wave function of quark clusters have a Gaussian form. With this parametrization, the Tolman-Oppenheimer-Volkoff equation is solved with reasonably constrained parameter space to give mass-radius relations of crystalline solid quark stars. With baryon number densities truncated at 2n 0 at surface and the range of the interaction fixed at 2 fm we can reproduce similar mass-radius relations to that obtained with bag model equations of state. The maximum mass ranges from ∼ 0.5 solar mass to approx.> 3 solar mass . The recently measured high pulsar mass (approx.> 2 solar mass ) is then used to constrain the parameters of this simple interaction potential. (authors)

  9. Performance of LiCl Impregnated Mesoporous Material Coating over Corrugated Heat Exchangers in a Solid Sorption Chiller

    Hongzhi Liu

    2018-06-01

    Full Text Available The composite material made by impregnating 40 wt. % lithium chloride (LiCl into the mesopores of a kind of natural porous rock (Wakkanai Siliceous Shale: WSS micropowders (short for “WSS + 40 wt. % LiCl” had been developed previously, and can be regenerated below 100 °C with a cooling coefficient of performance (COP of approximately 0.3 when adopted as a sorbent in a sorption cooler. In this study, experiments have been carried out on an intermittent solid sorption chiller with the WSS + 40 wt. % LiCl coating over two aluminum corrugated heat exchangers. Based on the experimental condition (regeneration temperature of 80 °C, condensation temperature of 30 °C in the desorption process; sorption temperature of 30 °C and evaporation temperature of 12 °C in the sorption process, the water sorption amount changes from 20 wt. % to 70 wt. % in one sorption cooling cycle. Moreover, a specific cooling power (SCP of 86 W/kg, a volumetric specific cooling power (VSCP of 42 W/dm3, and a specific sorption power of 170 W/kg can be achieved with a total sorption and desorption time of 20 min. The obtained cooling COP is approximately 0.16.

  10. Quarks for hadrons and leptons

    Lopes, J.L.

    1975-01-01

    The simplest, naive, model for a unified description of leptons and hadrons consists in postulating, besides the usual quarks p, n, lambda a fourth quark, with very heavy mass and very high binding to pairs like anti p n and anti p lambda. In a SU(4) scheme the fourth quark has a quantum number charm which may be taken as proportional to the lepton number. Muons would be distinguished from electrons by the occurence of a lambda-quark instead of a n-quark in their structure. The forces among these quarks would have to be such as to give leptons an almost point-like structure at the experimentally known energies as well as absence of strong interactions at these energies. However, one would expect the display of strong interactions by leptons at extremely high energies [pt

  11. Static quark-antiquark potential

    Deo, B.B.; Barik, B.K.

    1983-01-01

    A heavy-quark--antiquark potential is suggested which connects asymptotic freedom and quark confinement in a unified manner by formal methods of field theory using some plausible assumptions. The potential has only one additional adjustable parameter B which is proportional to (M/sub q//m/sub q/), where M/sub q/ and m/sub q/ are the constituent and current quark masses, respectively

  12. Infrared slavery and quark confinement

    Alabiso, C

    1976-01-01

    The question is considered of whether the so-called infrared slavery mechanism as, e.g., being manifest in non-Abelian gauge theories, necessarily confines quarks. Making a specific ansatz for the long- range forces, the Schwinger-Dyson equation is solved for the quark Green function. Besides having a confining solution, it appears that quarks may by-pass the long-range forces and be produced. (20 refs).

  13. Infrared slavery and quark confinement

    Alabiso, C.; Schierholz, G.

    1976-01-01

    The question of whether the so-called infrared slavery mechanism as, e.g., being manifest in non-Abelian gauge theories, necessarily confines quarks is posed. Making a specific ansatz for the long-range forces, the Schwinger-Dyson equation is solved for the quark Green function. Besides having a confining solution, it appears that quarks may by-pass the long-range forces and be produced. (Auth.)

  14. Exotic Signals of Vectorlike Quarks

    Dobrescu, Bogdan A. [Fermilab; Yu, Felix [U. Mainz, PRISMA

    2016-12-06

    Vectorlike fermions are an important target for hadron collider searches. We show that the vectorlike quarks may predominantly decay via higher-dimensional operators into a quark plus a couple of other Standard Model fermions. Pair production of vectorlike quarks of charge 2/3 at the LHC would then lead to a variety of possible final states, including $t\\bar t + 4\\tau$, $t\\bar b\

  15. Phenomenology of heavy quark systems

    Gilman, F.J.

    1987-03-01

    The spectroscopy of heavy quark systems is examined with regards to spin independent and spin dependent potentials. It is shown that a qualitative picture exists of the spin-independent forces, and that a semi-quantitative understanding exists for the spin-dependent effects. A brief review is then given of the subject of the decays of hadrons containing heavy quarks, including weak decays at the quark level, and describing corrections to the spectator model

  16. Quark matter or new particles?

    Michel, F. Curtis

    1988-01-01

    It has been argued that compression of nuclear matter to somewhat higher densities may lead to the formation of stable quark matter. A plausible alternative, which leads to radically new astrophysical scenarios, is that the stability of quark matter simply represents the stability of new particles compounded of quarks. A specific example is the SU(3)-symmetric version of the alpha particle, composed of spin-zero pairs of each of the baryon octet (an 'octet' particle).

  17. Influence of forced internal air circulation on airflow distribution and heat transfer in a gas double-dynamic solid-state fermentation bioreactor.

    Chen, Hongzhang; Qin, Lanzhi; Li, Hongqiang

    2014-02-01

    Internal air circulation affects the temperature field distribution in a gas double-dynamic solid-state fermentation bioreactor (GDSFB). To enhance heat transfer through strengthening internal air circulation in a GDSFB, we put an air distribution plate (ADP) into the bioreactor and studied the effects of forced internal air circulation on airflow, heat transfer, and cellulase activity of Trichoderma viride L3. Results showed that ADP could help form a steady and uniform airflow distribution, and with gas-guide tubes, air reversal was formed inside the bioreactor, thus resulting in a smaller temperature difference between medium and air by enhancing convective heat transfer inside the bioreactor. Using an ADP of 5.35 % aperture ratio caused a 1 °C decrease in the average temperature difference during the solid-state fermentation process of T. viride L3. Meanwhile, the cellulase activity of T. viride L3 increased by 13.5 %. The best heat-transfer effect was attained when using an ADP of 5.35 % aperture ratio and setting the fan power to 125 V (4.81 W) in the gas double-dynamic solid-state fermentation (GDSF) process. An option of suitable aperture ratio and fan power may be conducive to ADPs' industrial amplification.

  18. Effect of culture levels, ultrafiltered retentate addition, total solid levels and heat treatments on quality improvement of buffalo milk plain set yoghurt.

    Yadav, Vijesh; Gupta, Vijay Kumar; Meena, Ganga Sahay

    2018-05-01

    Studied the effect of culture (2, 2.5 and 3%), ultrafiltered (UF) retentate addition (0, 11, 18%), total milk solids (13, 13.50, 14%) and heat treatments (80 and 85 °C/30 min) on the change in pH and titratable acidity (TA), sensory scores and rheological parameters of yoghurt. With 3% culture levels, the required TA (0.90% LA) was achieved in minimum 6 h incubation. With an increase in UF retentate addition, there was observed a highly significant decrease in overall acceptability, body and texture and colour and appearance scores, but there was highly significant increase in rheological parameters of yoghurt samples. Yoghurt made from even 13.75% total solids containing nil UF retentate was observed to be sufficiently firm by the sensory panel. Most of the sensory attributes of yoghurt made with 13.50% total solids were significantly better than yoghurt prepared with either 13 or 14% total solids. Standardised milk heated to 85 °C/30 min resulted in significantly better overall acceptability in yoghurt. Overall acceptability of optimised yoghurt was significantly better than a branded market sample. UF retentate addition adversely affected yoghurt quality, whereas optimization of culture levels, totals milk solids and others process parameters noticeably improved the quality of plain set yoghurt with a shelf life of 15 days at 4 °C.

  19. Four-quark bound states

    Zouzou, S.

    1986-01-01

    In the framework of simple non-relativistic potential models, we examine the system consisting of two quarks and two antiquarks with equal or unequal masses. We search for possible bound states below the threshold for the spontaneous dissociation into two mesons. We solve the four body problem by empirical or systematic variational methods and we include the virtual meson-meson components of the wave function. With standard two-body potentials, there is no proliferation of multiquarks. With unequal quark masses, we obtain however exotic (anti Qanti Qqq) bound states with a baryonic antidiquark-quark-quark structure very analogous to the heavy flavoured (Q'qq) baryons. (orig.)

  20. Hadron production at RHIC: recombination of quarks

    Fries, Rainer J [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States)

    2005-01-01

    We discuss quark recombination applied to the hadronization of a quark gluon plasma. It has been shown that the quark recombination model can explain essential features of hadron production measured in high energy heavy ion collisions.

  1. Cold quark matter in compact stars

    Franzon, B.; Fogaca, D. A.; Navarra, F. S. [Instituto de Fisica, Universidade de Sao Paulo Rua do Matao, Travessa R, 187, 05508-090 Sao Paulo, SP (Brazil); Horvath, J. E. [Instituto de Astronomia, Geofisica e Ciencias Atmosfericas, Universidade de Sao Paulo, Rua do Matao, 1226, 05508-090, Sao Paulo, SP (Brazil)

    2013-03-25

    We used an equation of state for the cold quark matter to the study of properties of quark stars. We also discuss the absolute stability of quark matter and compute the mass-radius relation for self-bound stars.

  2. Models of quark bags and their consequences

    Bogolubov, P.N.

    1977-01-01

    The development of the first Dubna Quark Bag and the results obtained in this way are considered. The idea of the first Dubna Quark Bag is as follows: baryons are constructed of three quarks measons are constructed of two quarks, and each quark is interpreted as the Dirac particle which moves in a scalar square well. The so-called quasiindependent quark model is considered too. It is a simple quark model based on an analogy with the shell model for nuclei. The quarks are considered as moving in an arbitrary radially-symmetric field, and their one-particle wave function satisfies the usual Dirac equation. Such quark model can give at least the same results as the relativistic bag model. A possibility exists to improve the results of the relativistic quark model with the oscillator interaction between quarks. The results of the MIT-Bag model and the quasiindependent quark model coincide

  3. Quark and Gluon Relaxation in Quark-Gluon Plasmas

    Heiselberg, H.; Pethick, C. J.

    1993-01-01

    The quasiparticle decay rates for quarks and gluons in quark-gluon plasmas are calculated by solving the kinetic equation. Introducing an infrared cutoff to allow for nonperturbative effects, we evaluate the quasiparticle lifetime at momenta greater than the inverse Debye screening length to leading order in the coupling constant.

  4. From hadrons to quarks in neutron stars: a review

    Baym, Gordon; Hatsuda, Tetsuo; Kojo, Toru; Powell, Philip D.; Song, Yifan; Takatsuka, Tatsuyuki

    2018-05-01

    In recent years our understanding of neutron stars has advanced remarkably, thanks to research converging from many directions. The importance of understanding neutron star behavior and structure has been underlined by the recent direct detection of gravitational radiation from merging neutron stars. The clean identification of several heavy neutron stars, of order two solar masses, challenges our current understanding of how dense matter can be sufficiently stiff to support such a mass against gravitational collapse. Programs underway to determine simultaneously the mass and radius of neutron stars will continue to constrain and inform theories of neutron star interiors. At the same time, an emerging understanding in quantum chromodynamics (QCD) of how nuclear matter can evolve into deconfined quark matter at high baryon densities is leading to advances in understanding the equation of state of the matter under the extreme conditions in neutron star interiors. We review here the equation of state of matter in neutron stars from the solid crust through the liquid nuclear matter interior to the quark regime at higher densities. We focus in detail on the question of how quark matter appears in neutron stars, and how it affects the equation of state. After discussing the crust and liquid nuclear matter in the core we briefly review aspects of microscopic quark physics relevant to neutron stars, and quark models of dense matter based on the Nambu–Jona–Lasinio framework, in which gluonic processes are replaced by effective quark interactions. We turn then to describing equations of state useful for interpretation of both electromagnetic and gravitational observations, reviewing the emerging picture of hadron-quark continuity in which hadronic matter turns relatively smoothly, with at most only a weak first order transition, into quark matter with increasing density. We review construction of unified equations of state that interpolate between the reasonably well

  5. The discovery of the top quark

    Sinervo, P.K.

    1995-12-01

    The top quark and the Higgs boson are the heaviest elementary particles predicted by the standard model. The four lightest quark flavours, the up, down, strange and charm quarks, were well-established by the mid-1970's. The discovery in 1977 of the Τ resonances, a new family of massive hadrons, required the introduction of the fifth quark flavour. Experimental and theoretical studies have indicated that this quark also has a heavier partner, the top quark

  6. The Discovery of the Top Quark

    Sinervo, P.K.

    1995-12-01

    The top quark and the Higgs boson are the heaviest elementary particles predicted by the standard model. The four lightest quark flavours, the up, down, strange and charm quarks, were well-established by the mid-1970's. The discovery in 1977 of the {Tau} resonances, a new family of massive hadrons, required the introduction of the fifth quark flavour. Experimental and theoretical studies have indicated that this quark also has a heavier partner, the top quark.

  7. Heating-induced inner-sphere substitution and reduction-oxidation reactions of the solid phenanthroline containing cobalt (2) and cobalt (3) complexes

    Palade, D.M.

    1996-01-01

    The results of the differential thermal and thermogravimetric analyses of solid phenanthroline-containing complexes of cobalt (2) and cobalt (3) in the atmosphere of the air have been analyzed. Mechanism of redox reactions occurring when cobalt (3) complexes are heated has been discussed. It is shown that some of gaseous products of the redox processes appear as a result of secondary reactions and not the processes of the ligands oxidation by Co 3+ . The influence of certain inner-sphere and coordinated anions (of I, inclusively) on cobalt (3) complexes behaviour during heating has been considered

  8. Quark matter 93

    Otterlund, Ingvar; Ruuskanen, Vesa

    1993-12-15

    In his welcome address to the 10th International Conference on Ultra- Relativistic Nucleus-Nucleus Collisions (Quark Matter '93), held in Borlange, Sweden, from 20-24 June, Hans-Ake Gustafsson was puzzled why this year's conference was billed as the tenth in the series. He had tried to count but could only find eight forerunners - Bielefeld (1982), Brookhaven (1983), Helsinki (1984), Asilomar (1986), Nordkirchen (1987), Lenox (1988), Menton (1990), Gatlinburg (1991), making this year's meeting at Borlange the ninth. The answer was given by Helmut Satz in his introductory talk, pointing out that at the time of the Bielefeld meeting, a few conferences dealing with similar topics had already been held. The Bielefeld organizers thus did not consider their conference the first. Whatever its pedigree, the Borlange meeting covered particle production in highly excited and compressed nuclear matter, fluctuations and correlations, quark phenomena (quantum chromodynamics - QCD) in nuclear collisions, probes and signatures of Quark-Gluon Plasma (QGP), future collider experiments and instrumentation. The theoretical talks were split between the fundamental properties of the hot and dense matter at or near equilibrium, and the interface between theory and experiment. The phenomenological modelling of heavy ion collisions seems to reproduce at least all the main features of the data with hadrons, resonances and strings as the degrees of freedom. However secondary interactions among the produced hadrons or strings need to be added. Hydrodynamic calculations lead to results which reproduce the main features of the collisions. With increasing collision energy, the parton degrees of freedom become more important. Klaus Geiger described an ambitious scheme treating the whole nucleus-nucleus collision in terms of a kinetic parton (quark/gluon) cascade. The initial parton distribution at the beginning of the collision is determined from the quark-gluon nuclear structure and the

  9. Quark matter 93

    Otterlund, Ingvar; Ruuskanen, Vesa

    1993-01-01

    In his welcome address to the 10th International Conference on Ultra- Relativistic Nucleus-Nucleus Collisions (Quark Matter '93), held in Borlange, Sweden, from 20-24 June, Hans-Ake Gustafsson was puzzled why this year's conference was billed as the tenth in the series. He had tried to count but could only find eight forerunners - Bielefeld (1982), Brookhaven (1983), Helsinki (1984), Asilomar (1986), Nordkirchen (1987), Lenox (1988), Menton (1990), Gatlinburg (1991), making this year's meeting at Borlange the ninth. The answer was given by Helmut Satz in his introductory talk, pointing out that at the time of the Bielefeld meeting, a few conferences dealing with similar topics had already been held. The Bielefeld organizers thus did not consider their conference the first. Whatever its pedigree, the Borlange meeting covered particle production in highly excited and compressed nuclear matter, fluctuations and correlations, quark phenomena (quantum chromodynamics - QCD) in nuclear collisions, probes and signatures of Quark-Gluon Plasma (QGP), future collider experiments and instrumentation. The theoretical talks were split between the fundamental properties of the hot and dense matter at or near equilibrium, and the interface between theory and experiment. The phenomenological modelling of heavy ion collisions seems to reproduce at least all the main features of the data with hadrons, resonances and strings as the degrees of freedom. However secondary interactions among the produced hadrons or strings need to be added. Hydrodynamic calculations lead to results which reproduce the main features of the collisions. With increasing collision energy, the parton degrees of freedom become more important. Klaus Geiger described an ambitious scheme treating the whole nucleus-nucleus collision in terms of a kinetic parton (quark/gluon) cascade. The initial parton distribution at the beginning of the collision is determined from the quark-gluon nuclear structure

  10. Hot nuclear matter in the modified quark-meson coupling model with quark-quark correlations

    Zakout, I.; Jaqaman, H.R.

    2000-01-01

    Short-range quark-quark correlations in hot nuclear matter are examined within the modified quark-meson coupling (MQMC) model by adding repulsive scalar and vector quark-quark interactions. Without these correlations, the bag radius increases with the baryon density. However, when the correlations are introduced the bag size shrinks as the bags overlap. Also as the strength of the scalar quark-quark correlation is increased, the decrease of the effective nucleon mass M* N with the baryonic density is slowed down and tends to saturate at high densities. Within this model we study the phase transition from the baryon-meson phase to the quark-gluon plasma (QGP) phase with the latter modelled as an ideal gas of quarks and gluons inside a bag. Two models for the QGP bag parameter are considered. In one case, the bag is taken to be medium-independent and the phase transition from the hadron phase to QGP is found to occur at five to eight times ordinary nuclear matter density for temperatures less than 60 MeV. For lower densities, the transition takes place at a higher temperature, reaching up to 130 MeV at zero density. In the second case, the QGP bag parameter is considered to be medium-dependent as in the MQMC model for the hadronic phase. In this case, it is found that the phase transition occurs at much lower densities. (author)

  11. Quark fragmentation function and the nonlinear chiral quark model

    Zhu, Z.K.

    1993-01-01

    The scaling law of the fragmentation function has been proved in this paper. With that, we show that low-P T quark fragmentation function can be studied as a low energy physocs in the light-cone coordinate frame. We therefore use the nonlinear chiral quark model which is able to study the low energy physics under scale Λ CSB to study such a function. Meanwhile the formalism for studying the quark fragmentation function has been established. The nonlinear chiral quark model is quantized on the light-front. We then use old-fashioned perturbation theory to study the quark fragmentation function. Our first order result for such a function shows in agreement with the phenomenological model study of e + e - jet. The probability for u,d pair formation in the e + e - jet from our calculation is also in agreement with the phenomenological model results

  12. Cool quark matter

    Kurkela, Aleksi

    2016-07-20

    We generalize the state-of-the-art perturbative Equation of State of cold quark matter to nonzero temperatures, needed in the description of neutron star mergers and core collapse processes. The new result is accurate to order g^5 in the gauge coupling, and is based on a novel framework for dealing with the infrared sensitive soft field modes of the theory. The zero Matsubara mode sector is treated using a dimensionally reduced effective theory, while the soft non-zero modes are resummed using the Hard Thermal Loop approximation. This combination of known effective descriptions offers unprecedented access to small but nonzero temperatures, both in and out of beta equilibrium.

  13. Heavy Quark Effective Theory

    Manohar, A. V.

    2003-02-01

    These lecture notes present some of the basic ideas of heavy quark effective theory. The topics covered include the classification of states, the derivation of the HQET Lagrangian at tree level, hadron masses, meson form factors, Luke's theorem, reparameterization invariance and inclusive decays. Radiative corrections are discussed in some detail, including an explicit computation of a matching correction for HQET. Borel summability, renormalons, and their connection with the QCD perturbation series is covered, as well as the use of the upsilon expansion to improve the convergence of the perturbation series.

  14. Performance of hybrid quad generation system consisting of solid oxide fuel cell system and absorption heat pump

    Cachorro, Irene Albacete; Daraban, Iulia Maria; Lainé, Guillaume

    2013-01-01

    . The heat pump is a heat driven system and is running with the heat recovered by a heat exchanger from the exhausted gases from SOFC. The working fluid pair is NH3-H2O and is driven in two evaporators which are working at two different pressures. Thus, the heat pump will operate at tree pressure level...... with natural gas. The natural gas is first converted to a mixture of H2 and CO which feed the anode after a preheating step. The cathode is supplied with preheated air and gives, as output, electrical energy. The anode output is the exhaust gas which represents the thermal energy reservoir for heating...

  15. Study of quark structure functions

    Dao, F.T.; Flaminio, E.; Lai, K.; Metcalf, M.; Wang, L.

    1977-01-01

    The quark structure functions of the proton are determined through a combined analysis of the reactions pN → ll-barX and eN → eX. The valence-quark structure function of the pion is also given by analyzing the πN → μμ-barX data measured by the Branson et al

  16. Hadron interactions in quark models

    Narodetskij, I.M.

    1987-01-01

    Some recent developments on the study of quark degrees of freedom in hadron scattering at intermediate energy are reviewed. Physical foundations of the P-matrix approach and the Quark Compound Bag method are discussed including applications to pion-pion, pion-nucleon, nucleon-nucleon and three-nucleon systems

  17. Quark models in hadron physics

    Phatak, Shashikant C.

    2007-01-01

    In this talk, we review the role played by the quark models in the study of interaction of strong, weak and electromagnetic probes with hadrons at intermediate and high momentum transfers. By hadrons, we mean individual nucleons as well as nuclei. We argue that at these momentum transfers, the structure of hadrons plays an important role. The hadron structure of the hadrons is because of the underlying quark structure of hadrons and therefore the quark models play an important role in determining the hadron structure. Further, the properties of hadrons are likely to change when these are placed in nuclear medium and this change should arise from the underlying quark structure. We shall consider some quark models to look into these aspects. (author)

  18. Heavy quark hadron mass scale

    Anderson, J.T.

    1994-01-01

    Without the spin interactions the hardron masses within a multiplet are degenerate. The light quark hadron degenerate mulitplet mass spectrum is extended from the 3 quark ground state multiplets at J P =0 - , 1/2 + , 1 - to include the excited states which follow the spinorial decomposition of SU(2)xSU(2). The mass scales for the 4, 5, 6, .. quark hadrons are obtained from the degenerate multiplet mass m 0 /M=n 2 /α with n=4, 5, 6, .. The 4, 5, 6, .. quark hadron degenerate multiplet masses follow by splitting of the heavy quark mass scales according to the spinorial decomposition of SU(2)xSU(2). (orig.)

  19. Quark matter and cosmology

    Schramm, D.N.; Fields, B.; Thomas, D.

    1992-01-01

    The possible implications of the quark-hadron transition for cosmology are explored. Possible surviving signatures are discussed. In particular, the possibility of generating a dark matter candidate such as strange nuggets or planetary mass black holes is noted. Much discussion is devoted to the possible role of the transition for cosmological nucleosynthesis. It is emphasized that even an optimized first order phase transition will not significantly alter the nucleosynthesis constraints on the cosmological baryon density nor on neutrino counting. However, it is noted that Be and B observations in old stars may eventually be able to be a signature of a cosmologically significant quark-hadron transition. It is pointed out that the critical point in this regard is whether the observed B/Be ratio can be produced by spallation processes or requires cosmological input. Spallation cannot produce a B/Be ratio below 7.6. A supporting signature would be Be and B ratios to oxygen that greatly exceed galactic values. At present, all data is still consistent with a spallagenic origin

  20. PREFACE: Quark Matter 2008

    Jan-e~Alam; Subhasis~Chattopadhyay; Tapan~Nayak

    2008-10-01

    Quark Matter 2008—the 20th International Conference on Ultra-Relativistic Nucleus-Nucleus Collisions was held in Jaipur, the Pink City of India, from 4-10 February, 2008. Organizing Quark Matter 2008 in India itself indicates the international recognition of the Indian contribution to the field of heavy-ion physics, which was initiated and nurtured by Bikash Sinha, Chair of the conference. The conference was inaugurated by the Honourable Chief Minister of Rajasthan, Smt. Vasundhara Raje followed by the key note address by Professor Carlo Rubbia. The scientific programme started with the theoretical overview, `SPS to RHIC and onwards to LHC' by Larry McLerran followed by several theoretical and experimental overview talks on the ongoing experiments at SPS and RHIC. The future experiments at the LHC, FAIR and J-PARC, along with the theoretical predictions, were discussed in great depth. Lattice QCD predictions on the nature of the phase transition and critical point were vigorously debated during several plenary and parallel session presentations. The conference was enriched by the presence of an unprecedented number of participants; about 600 participants representing 31 countries across the globe. This issue contains papers based on plenary talks and oral presentations presented at the conference. Besides invited and contributed talks, there were also a large number of poster presentations. Members of the International Advisory Committee played a pivotal role in the selection of speakers, both for plenary and parallel session talks. The contributions of the Organizing Committee in all aspects, from helping to prepare the academic programme down to arranging local hospitality, were much appreciated. We thank the members of both the committees for making Quark Matter 2008 a very effective and interesting platform for scientific deliberations. Quark Matter 2008 was financially supported by: Air Liquide (New Delhi) Board of Research Nuclear Sciences (Mumbai) Bose

  1. Energy density and storage capacity cost comparison of conceptual solid and liquid sorption seasonal heat storage systems for low-temperature space heating

    Scapino, L.; Zondag, H.A.; Van Bael, J.; Diriken, J.; Rindt, C.C.M.

    Sorption heat storage can potentially store thermal energy for long time periods with a higher energy density compared to conventional storage technologies. A performance comparison in terms of energy density and storage capacity costs of different sorption system concepts used for seasonal heat

  2. Using a quasi-heat-pulse method to determine heat and moisture transfer properties for porous orthotropic wood products or cellular solid materials

    M. A. Dietenberger

    2006-01-01

    Understanding heat and moisture transfer in a wood specimen as used in the K-tester has led to an unconventional numerical solution arid intriguing protocol to deriving the transfer properties. Laplace transform solutions of Luikov’s differential equations are derived for one-dimensional heat and moisture transfer in porous hygroscopic orthotropic materials and for a...

  3. Electromagnetic properties of light and heavy baryons in the relativistic quark model

    Nicmorus Marinescu, Diana

    2007-01-01

    One of the main challenges of nowadays low-energy physics remains the description of the internal structure of hadrons, strongly connected to the electromagnetic properties of matter. In this vein, the success of the relativistic quark model in the analysis of the hadron structure constitutes a solid motivation for the study carried out throughout this work. The relativistic quark model is extended to the investigation of static electromagnetic properties of both heavy and light baryons. The bare contributions to the magnetic moments of the single-, double- and triple-heavy baryons are calculated. Moreover, the relativistic quark model allows the study of the electromagnetic properties of the light baryon octet incorporating meson cloud contributions in a perturbative manner. The long disputed values of the multipole ratios E2/M1 and C2/M1 and the electromagnetic form factors of the N→Δγ transition are successfully reproduced. The relativistic quark model can be viewed as a quantum field theory approach based on a phenomenological Lagrangian coupling light and heavy baryons to their constituent quarks. In our approach the baryon is a composite object of three constituent quarks, at least in leading order. The effective interaction Lagrangian is written in terms of baryon and constituent quark fields. The effective action preserves Lorentz covariance and gauge invariance. The main ingredients of the model are already introduced at the level of the interaction Lagrangian: the three-quark baryon currents, the Gaussian distribution of the constituent quarks inside the baryon and the compositeness condition which sets an upper limit for the baryon-quark vertex. The S-matrix elements are expressed by a set of Feynman quark-diagrams. The model contains only few parameters, namely, the cut-off parameter of the Gaussian quark distribution and the free quark propagator, which are unambiguously determined from the best fit to the data. The heavy quark limit within this

  4. Electromagnetic properties of light and heavy baryons in the relativistic quark model

    Nicmorus Marinescu, Diana

    2007-06-14

    One of the main challenges of nowadays low-energy physics remains the description of the internal structure of hadrons, strongly connected to the electromagnetic properties of matter. In this vein, the success of the relativistic quark model in the analysis of the hadron structure constitutes a solid motivation for the study carried out throughout this work. The relativistic quark model is extended to the investigation of static electromagnetic properties of both heavy and light baryons. The bare contributions to the magnetic moments of the single-, double- and triple-heavy baryons are calculated. Moreover, the relativistic quark model allows the study of the electromagnetic properties of the light baryon octet incorporating meson cloud contributions in a perturbative manner. The long disputed values of the multipole ratios E2/M1 and C2/M1 and the electromagnetic form factors of the N{yields}{delta}{gamma} transition are successfully reproduced. The relativistic quark model can be viewed as a quantum field theory approach based on a phenomenological Lagrangian coupling light and heavy baryons to their constituent quarks. In our approach the baryon is a composite object of three constituent quarks, at least in leading order. The effective interaction Lagrangian is written in terms of baryon and constituent quark fields. The effective action preserves Lorentz covariance and gauge invariance. The main ingredients of the model are already introduced at the level of the interaction Lagrangian: the three-quark baryon currents, the Gaussian distribution of the constituent quarks inside the baryon and the compositeness condition which sets an upper limit for the baryon-quark vertex. The S-matrix elements are expressed by a set of Feynman quark-diagrams. The model contains only few parameters, namely, the cut-off parameter of the Gaussian quark distribution and the free quark propagator, which are unambiguously determined from the best fit to the data. The heavy quark limit

  5. Effect of constant and uniform heat generation on the thermal behaviour of porous solids with asymmetric boundary conditions

    Heggs, P.J.; Dare, J.

    2007-01-01

    The generation of heat due to chemical reaction will have a significant effect on the temperature profile and heat transfer within a porous body. Most forms of analysis only consider the symmetric situation or else make use of various assumptions that greatly simplify the analysis, for example: the Semenov or the Frak-kamenetskii models. The objective of this paper is to develop an improved understanding of the thermal behaviour of a porous body with uniform internal heat generation, which is in contact with two fluids at different temperatures and with different heat transfer coefficients. The mathematical representation is a one dimensional Poisson equation with asymmetric boundary conditions. The analytical solution reveals four regimes for heat flow: (a) purely conduction at zero heat generation, (b) a combination of heat flow by conduction through the body between the hot and cold fluids and all heat generated passing to the colder fluid, (c) no heat flow by conduction between the two fluids and all heat generated passing the cold flow - the so-called critical heat generation, and (d) the heat generated passes to both the cold and hot fluids and there is a maximum temperature within the body greater than that of the hot fluid, the so-called supercritical region. Expressions are developed to allow predictions of the conditions pertaining to each regime. This new representation covers the Semenov and Frank-Kamenetskii models and all possible solutions intermediate of the them. (authors)

  6. Rapid, non-destructive and non-contact inspection of solid foods by means of photothermal radiometry; thermal effusivity and initial heating coefficient

    Gijsbertsen, A.; Bicanic, D.; Gielen, J. L. W.; Chirtoc, M.

    2004-03-01

    CO 2-laser photothermal radiometry (PTR) was demonstrated to be suitable for the non-destructive and non-contact characterization (both optical and thermal) of solid phase agricultural commodities (fresh vegetables, fruits) and confectionery products (candy). Proper interpretation of PTR signals enable one to calculate two parameters, i.e. the well known thermal effusivity e ( e= λρc p, where λ and ρcp are the thermal conductivity and the volume specific heat, respectively) and a newly introduced physical quantity termed 'initial heating coefficient' chi ( χ= β/( ρcp), β is the absorption coefficient). Obtained values for e are in a good agreement with data reported in the literature. PTR enables one to rapidly determine e via a single measurement. As opposed to this, the knowledge of two out of three thermophysical parameters (thermal diffusivity, thermal conductivity and volume specific heat) is a condition sine qua non for determining effusivity in the conventional manner.

  7. Effect of radiation and magnetohydrodynamic free convection boundary layer flow on a solid sphere with Newtonian heating in a micropolar fluid

    Alkasasbeh, Hamzeh Taha; Sarif, Norhafizah Md; Salleh, Mohd Zuki; Tahar, Razman Mat; Nazar, Roslinda; Pop, Ioan

    2015-01-01

    In this paper, the effect of radiation on magnetohydrodynamic free convection boundary layer flow on a solid sphere with Newtonian heating in a micropolar fluid, in which the heat transfer from the surface is proportional to the local surface temperature, is considered. The transformed boundary layer equations in the form of nonlinear partial differential equations are solved numerically using an implicit finite difference scheme known as the Keller-box method. Numerical solutions are obtained for the local wall temperature and the local skin friction coefficient, as well as the velocity, angular velocity and temperature profiles. The features of the flow and heat transfer characteristics for various values of the Prandtl number Pr, micropolar parameter K, magnetic parameter M, radiation parameter N R , the conjugate parameter γ and the coordinate running along the surface of the sphere, x are analyzed and discussed

  8. Effect of radiation and magnetohydrodynamic free convection boundary layer flow on a solid sphere with Newtonian heating in a micropolar fluid

    Alkasasbeh, Hamzeh Taha, E-mail: zukikuj@yahoo.com; Sarif, Norhafizah Md, E-mail: zukikuj@yahoo.com; Salleh, Mohd Zuki, E-mail: zukikuj@yahoo.com [Futures and Trends Research Group, Faculty of Industrial Science and Technology, Universiti Malaysia Pahang, 26300 UMP Kuantan, Pahang (Malaysia); Tahar, Razman Mat [Faculty of Technology, Universiti Malaysia Pahang, 26300 UMP Kuantan, Pahang (Malaysia); Nazar, Roslinda [School of Mathematical Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor (Malaysia); Pop, Ioan [Department of Mathematics, Babeş-Bolyai University, R-400084 Cluj-Napoca (Romania)

    2015-02-03

    In this paper, the effect of radiation on magnetohydrodynamic free convection boundary layer flow on a solid sphere with Newtonian heating in a micropolar fluid, in which the heat transfer from the surface is proportional to the local surface temperature, is considered. The transformed boundary layer equations in the form of nonlinear partial differential equations are solved numerically using an implicit finite difference scheme known as the Keller-box method. Numerical solutions are obtained for the local wall temperature and the local skin friction coefficient, as well as the velocity, angular velocity and temperature profiles. The features of the flow and heat transfer characteristics for various values of the Prandtl number Pr, micropolar parameter K, magnetic parameter M, radiation parameter N{sub R}, the conjugate parameter γ and the coordinate running along the surface of the sphere, x are analyzed and discussed.

  9. Light-quark, heavy-quark systems: An update

    Grinstein, B.

    1993-06-01

    We review many of the recently developed applications of Heavy Quark Effective Theory techniques. After a brief update on Luke's theorem, we describe striking relations between heavy baryon form factors, and how to use them to estimate the accuracy of the extraction of (vert bar)V(sub cb)(vert bar). We discuss factorization and compare with experiment. An elementary presentation, with sample applications, of reparametrization invariance comes next. The final and most extensive chapter in this review deals with phenomenological lagrangians that incorporate heavy-quark spin-flavor as well as light quark chiral symmetries. We compile many interesting results and discuss the validity of the calculations.

  10. Light-quark, heavy-quark systems: An update

    Grinstein, B.

    1993-01-01

    The author reviews many of the recently developed applications of Heavy Quark Effective Theory techniques. After a brief update on Luke's theorm, he describes striking relations between heavy baryon form factors, and how to use them to estimate the accuracy of the extraction of |B cb |. He discusses factorization and compares with experiment. An elementary presentation, with sample applications, of reparametrization invariance comes next. The final and most extensive chapter in this review deals with phenomenological lagrangians that incorporate heavy-quark spin-flavor as well as light quark chiral symmetries. He compiles many interesting results and discuss the validity of the calculations

  11. A Model-Independent Discussion of Quark Number Density and Quark Condensate at Zero Temperature and Finite Quark Chemical Potential

    Xu Shu-Sheng; Shi Chao; Cui Zhu-Fang; Zong Hong-Shi; Jiang Yu

    2015-01-01

    Generally speaking, the quark propagator is dependent on the quark chemical potential in the dense quantum chromodynamics (QCD). By means of the generating functional method, we prove that the quark propagator actually depends on p_4 + iμ from the first principle of QCD. The relation between quark number density and quark condensate is discussed by analyzing their singularities. It is concluded that the quark number density has some singularities at certain μ when T = 0, and the variations of the quark number density as well as the quark condensate are located at the same point. In other words, at a certain μ the quark number density turns to nonzero, while the quark condensate begins to decrease from its vacuum value. (paper)

  12. A comparison between two methods of generating power, heat and refrigeration via biomass based Solid Oxide Fuel Cell: A thermodynamic and environmental analysis

    Mortazaei, M.; Rahimi, M.

    2016-01-01

    Highlights: • Two novel trigeneration systems based biomass and Solid Oxide Fuel Cell are compared. • A complete environmental analysis for three different cases is conducted. • Digester based system has 14.56% more exergetic efficiency than gasifier based one. • Gasifier based system has 14.31% more energetic efficiency than Digester based one. • Gasifier, Digester and air heat exchanger have the highest exergy destruction. - Abstract: Utilization of biomass energy is of prevalence focus these days. Using these fuels to run the fuel cells is of primary interest. In this regard, two new trigeneration systems (producing power and heating alongside with cooling) based on solid oxide fuel cell fed by either the syngas or biogas are proposed. The performance of systems is analyzed and compared with each other from the thermodynamic viewpoint. Applying the conservation of mass and energy as well as the exergy for each system component and using the engineering equation solver, the system’s performance are modeled. Through a parametric study, the effects of some key variables such as the current density and the fuel utilization factor in the systems’ performance are investigated. In addition, considering the system as a combination of three subsystems, that is, the power generation system, heat and power generation system and trigeneration system, an environmental impact assessment in terms of Carbon dioxide emission is carried out for both digester based Solid Oxide Fuel Cell and gasifier based one. It is observed that using biogas from digester leads to more exergetic (which is 14.56%) and less energetic efficiency (Which is 14.31%), with a Carbon dioxide emission of 17.87 ton/MW h for the tri-generation system. The value of this parameter is 21.32 ton/MW h when gasifier is used as the supplier of fuel for solid oxide fuel cell.

  13. How the physicists nailed the quarks

    Anon.

    1985-01-01

    The paper reviews quarks, from its prediction in 1962, to the experiments confirming its existence in the 1970's and 1980's. The elementary particles of matter; building particles from quarks; why quarks can never be isolated; and the six quarks; are all discussed. (U.K.)

  14. Baryons in the unquenched quark model

    Bijker, R.; Díaz-Gómez, S. [Instituto de Ciencias Nucleares, Universidad Nacional Autónoma de México, AP 70-543, 04510 Mexico DF (Mexico); Lopez-Ruiz, M. A. [Physics Department and Center for Exploration of Energy and Matter, Indiana University, Bloomington, IN 47408 (United States); Santopinto, E. [Istituto Nazionale di Fisica Nucleare, Sezione di Genova, via Dodecaneso 33, I-16146 Italy (Italy)

    2016-07-07

    In this contribution, we present the unquenched quark model as an extension of the constituent quark model that includes the effects of sea quarks via a {sup 3}P{sub 0} quark-antiquark pair-creation mechanism. Particular attention is paid to the spin and flavor content of the proton, magnetic moments and β decays of octet baryons.

  15. Heavy baryons in the relativistic quark model

    Ebert, D.; Faustov, R.N.; Galkin, V.O.; Martynenko, A.P.; Saleev, V.A.

    1996-07-01

    In the framework of the relativistic quasipotential quark model the mass spectrum of baryons with two heavy quarks is calculated. The quasipotentials for interactions of two quarks and of a quark with a scalar and axial vector diquark are evaluated. The bound state masses of baryons with J P =1/2 + , 3/2 + are computed. (orig.)

  16. Top quark physics

    Menzione, A.

    1995-10-01

    Most of the material presented in this report, comes from contributions to the parallel session PL20 of this conference. We summarise the experimental results of direct production of Top quarks, coming from the CDF and C0 Collaborations at Fermilab, and compare these results to what one expects within current theoretical understanding. Particular attention is given to new results such as all hadronic modes of t bar t decay. As far as the mass is concerned, a comparison is made with precision measurements of related quantities, coming from LEP and other experiments. An attempt is made to look at the medium-term future and understand which variables and with what accuracy one can measure them with increased integrated luminosity

  17. Quarks and partons

    Close, F.E.

    1976-01-01

    The studies of inelastic electron scattering at SLAC and of neutrino scattering at CERN have been widely interpreted as giving support to the idea that the nucleon is built from elementary constituents, called partons, and that these partons have the same quantum numbers as the quarks that are familiar in spectroscopy. In particular, a very simple regularity in the data, known as scale invariance or just 'scaling' was seen at least at moderate energies (2 2 > approximately 1 GeV) which is natural in the parton model. The data on e + e - annihilation also appear to be consistent with scaling when Esub(cm) approximately 5 GeV. These lectures are concerned with the scaling phenomena. One may expect the new hadronic degree of freedom to generate scaling violations in inelastic electron and neutrino scattering. These are mentioned briefly in these lectures. (Auth.)

  18. Quarks and numerical simulation

    Weingarten, D.

    1996-01-01

    This work deals with the quantum chromodynamics and the theory of quarks's behaviour. The experimentation supports this theory but until now no computation have prove it. The resolution of the mathematic equations were far beyond the capability of human or the quickest computer of the seventies. A dedicated computer was built: the GF11. The mass of eight hadrons was computed in 91. In 95, a new particle was found by computation. The author explains the mathematical modeling of chromodynamics and the methods to solve it. It requires 10 17 arithmetic operations. So specific computer is needed. GF11 uses 566 processors in parallel. New machines hundred of times more efficient will be needed to go further. That will be a new tool for theorician physicists. (O.M.). 9 refs., 2 figs., 1 tab

  19. Indoor concentrations of nitrogen dioxide and sulfur dioxide from burning solid fuels for cooking and heating in Yunnan Province, China

    Seow, Wei Jie; Downward, George S; Wei, Hu; Rothman, Nathaniel; Reiss, Boris; Xu, Jun; Bassig, Bryan A; Li, Jihua; He, Jun; Hosgood, H Dean; Wu, Guoping; Chapman, Robert S; Tian, Linwei; Wei, Fusheng; Caporaso, Neil E; Vermeulen, Roel; Lan, Qing

    2016-01-01

    The Chinese national pollution census has indicated that the domestic burning of solid fuels is an important contributor to nitrogen dioxide (NO2 ) and sulfur dioxide (SO2 ) emissions in China. To characterize indoor NO2 and SO2 air concentrations in relation to solid fuel use and stove ventilation

  20. Resource Letter Q-1: quarks

    Greenberg, O.W.

    1982-01-01

    Quarks as fundamental constituents of hadrons play a central role in elementary particle physics. We give an annotated bibliography of references to quarks and related topics in elementary particle physics, as well as to the role of quarks in areas outside elementary particle physics, such as nuclear physics, and astrophysics and cosmology. We label references E (elementary), I (intermediate), and A (advanced) to guide the reader. Articles selected for incorporation in a reprint volume (to be published separately by the American Association of Physics Teachers) are indicated by an an asterisk. A short list of particularly helpful elementary and intermediate references is indicated by a star

  1. Weak decays of heavy quarks

    Gaillard, M.K.

    1978-08-01

    The properties that may help to identify the two additional quark flavors that are expected to be discovered. These properties are lifetime, branching ratios, selection rules, and lepton decay spectra. It is also noted that CP violation may manifest itself more strongly in heavy particle decays than elsewhere providing a new probe of its origin. The theoretical progress in the understanding of nonleptonic transitions among lighter quarks, nonleptonic K and hyperon decay amplitudes, omega minus and charmed particle decay predictions, and lastly the Kobayashi--Maskawa model for the weak coupling of heavy quarks together with the details of its implications for topology and bottomology are treated. 48 references

  2. Holographic lessons for quark dynamics

    Chernicoff, Mariano; García, J. Antonio; Güijosa, Alberto; Pedraza, Juan F.

    2012-05-01

    We give a brief overview of recent results obtained through the gauge/gravity correspondence, concerning the propagation of a heavy quark in strongly coupled conformal field theories (such as {N}=4 super-Yang-Mills), both at zero and finite temperature. In the vacuum, we discuss energy loss, radiation damping, signal propagation and radiation-induced fluctuations. In the presence of a thermal plasma, our emphasis is on early-time energy loss, screening and quark-antiquark evolution after pair creation. Throughout, quark dynamics is seen to be efficiently encapsulated in the usual string worldsheet dynamics.

  3. How many quarks are there

    Harari, H

    1976-01-01

    The experimental information which was accumulated in the last 18 months in e/sup +/e/sup -/ collisions and ..nu..N scattering indicates that more than four kinds of quarks are already present. Six different pieces of evidence for the existence of six quarks: the triangle anomalies, the value of R, psi-spectroscopy, neutrino processes, CP-violation and the possible existence of V+A currents are discussed. It is concluded that there is strong (but not yet conclusive) evidence for the existence of six quarks and six leptons.

  4. How many quarks are there

    Harari, Haim

    The experimental information which was accumulated in the last 18 months in e + e - collisions and neutrino+N scattering indicates that more than four kinds of quarks are already present. Six different pieces of evidence for the existence of six quarks are discussed: the triangle anomalies, the value of R, psi-spectroscopy, neutrino processes, CP-violation and the possible existence of V+A currents. It is concluded that there is strong (but not yet conclusive) evidence for the existence of six quarks and six leptons

  5. Decays of the b quark

    Thorndike, E.H.; Poling, R.A.

    1988-01-01

    Recent experimental results on the decay of b-flavored hadrons are reviewed. Substantial progress has been made in the study of exclusive and inclusive B-meson decays, as well as in the theoretical understanding of these processes. The two most prominent developments are the continuing failure to observe evidence of decays of the b quark to a u quark rather than a c quark, and the surprisingly high level of B 0 -anti B 0 mixing which has recently been reported by the ARGUS collaboration. Notwithstanding these results, we conclude that the health of the Standard Model is excellent. (orig.)

  6. Quark chiral condensate from the overlap quark propagator

    Wang, Chao; Bi, Yujiang; Cai, Hao; Chen, Ying; Gong, Ming; Liu, Zhaofeng

    2017-05-01

    From the overlap lattice quark propagator calculated in the Landau gauge, we determine the quark chiral condensate by fitting operator product expansion formulas to the lattice data. The quark propagators are computed on domain wall fermion configurations generated by the RBC-UKQCD Collaborations with N f = 2+1 flavors. Three ensembles with different light sea quark masses are used at one lattice spacing 1/a = 1.75(4) GeV. We obtain in the SU(2) chiral limit. Supported by National Natural Science Foundation of China (11575197, 11575196, 11335001, 11405178), joint funds of NSFC (U1632104, U1232109), YC and ZL acknowledge the support of NSFC and DFG (CRC110)

  7. Diquark condensation and the quark-quark interaction

    Bloch, J. C. R.; Roberts, C. D.; Schmidt, S. M.

    1999-01-01

    We employ a bispinor gap equation to study superfluidity at nonzero chemical potential, μ≠0, in two- and three-color QCD, exploring the gap's sensitivity to the nature of the quark-quark interaction. The two-color theory, QC 2 D, is an excellent exemplar; the order of truncation of the quark-quark scattering kernel K has no qualitative impact, which allows a straightforward elucidation of the effects of μ when the coupling is strong. In the three-color theory the rainbow-ladder truncation admits diquark bound states, a defect that is eliminated by an improvement of K. The corrected gap equation describes a superfluid phase that is semiquantitatively similar to that obtained using the rainbow truncation. A model study suggests that the width of the superfluid gap and the transition point in QC 2 D provide reliable quantitative estimates of those quantities in QCD. (c) 1999 The American Physical Society

  8. Quark-anti-quark potential in N=4 SYM

    Gromov, Nikolay [Mathematics Department, King’s College London,The Strand, London WC2R 2LS (United Kingdom); St. Petersburg INP,Gatchina, 188 300, St.Petersburg (Russian Federation); Levkovich-Maslyuk, Fedor [Mathematics Department, King’s College London,The Strand, London WC2R 2LS (United Kingdom); Nordita, KTH Royal Institute of Technology and Stockholm University, Roslagstullsbacken 23, SE-106 91 Stockholm (Sweden)

    2016-12-22

    We construct a closed system of equations describing the quark-anti-quark potential at any coupling in planar N=4 supersymmetric Yang-Mills theory. It is based on the Quantum Spectral Curve method supplemented with a novel type of asymptotics. We present a high precision numerical solution reproducing the classical and one-loop string predictions very accurately. We also analytically compute the first 7 nontrivial orders of the weak coupling expansion. Moreover, we study analytically the generalized quark-anti-quark potential in the limit of large imaginary twist to all orders in perturbation theory. We demonstrate how the QSC reduces in this case to a one-dimensional Schrodinger equation. In the process we establish a link between the Q-functions and the solution of the Bethe-Salpeter equation.

  9. Top quark studies at hadron colliders

    Sinervo, P.K. [Univ. of Toronto, Ontario (Canada)

    1997-01-01

    The techniques used to study top quarks at hadron colliders are presented. The analyses that discovered the top quark are described, with emphasis on the techniques used to tag b quark jets in candidate events. The most recent measurements of top quark properties by the CDF and DO Collaborations are reviewed, including the top quark cross section, mass, branching fractions, and production properties. Future top quark studies at hadron colliders are discussed, and predictions for event yields and uncertainties in the measurements of top quark properties are presented.

  10. Quark virtuality and QCD vacuum condensates

    Zhou Lijuan; Ma Weixing

    2004-01-01

    Based on the Dyson-Schwinger equations (DSEs) in the 'rainbow' approximation, the authors investigate the quark virtuality in the vacuum state and quantum-chromodynamics (QCD) vacuum condensates. In particular, authors calculate the local quark vacuum condensate and quark-gluon mixed condensates, and then the virtuality of quark. The calculated quark virtualities are λ u,d 2 =0.7 GeV 2 for u, d quarks, and λ s 2 =1.6 GeV 2 for s quark. The theoretical predictions are consistent with empirical values used in QCD sum rules, and also fit to lattice QCD predictions

  11. Top quark studies at hadron colliders

    Sinervo, P.K.

    1997-01-01

    The techniques used to study top quarks at hadron colliders are presented. The analyses that discovered the top quark are described, with emphasis on the techniques used to tag b quark jets in candidate events. The most recent measurements of top quark properties by the CDF and DO Collaborations are reviewed, including the top quark cross section, mass, branching fractions, and production properties. Future top quark studies at hadron colliders are discussed, and predictions for event yields and uncertainties in the measurements of top quark properties are presented

  12. Top quark studies at hadron colliders

    Sinervo, P.K.

    1996-08-01

    The techniques used to study top quarks at hadron colliders are presented. The analyses that discovered the top quark are described, with emphasis on the techniques used to tag b quark jets in candidate events. The most recent measurements of top quark properties by the CDF and D null collaborations are reviewed, including the top quark cross section, mass, branching fractions and production properties. Future top quark studies at hadron colliders are discussed, and predictions for event yields and uncertainties in the measurements of top quark properties are presented

  13. Properties of the Top Quark

    Wicke, Daniel; /Wuppertal U., Dept. Math.

    2009-08-01

    The aim of particle physics is the understanding of elementary particles and their interactions. The current theory of elementary particle physics, the Standard Model, contains twelve different types of fermions which (neglecting gravity) interact through the gauge bosons of three forces. In addition a scalar particle, the Higgs boson, is needed for theoretical consistency. These few building blocks explain all experimental results found in the context of particle physics, so far. Nevertheless, it is believed that the Standard Model is only an approximation to a more complete theory. First of all the fourth known force, gravity, has withstood all attempts to be included until now. Furthermore, the Standard Model describes several features of the elementary particles like the existence of three families of fermions or the quantisation of charges, but does not explain these properties from underlying principles. Finally, the lightness of the Higgs boson needed to explain the symmetry breaking is difficult to maintain in the presence of expected corrections from gravity at high scales. This is the so called hierarchy problem. In addition astrophysical results indicate that the universe consists only to a very small fraction of matter described by the Standard Model. Large fractions of dark energy and dark matter are needed to describe the observations. Both do not have any correspondence in the Standard Model. Also the very small asymmetry between matter and anti-matter that results in the observed universe built of matter (and not of anti-matter) cannot be explained until now. It is thus an important task of experimental particle physics to test the predictions of the Standard Model to the best possible accuracy and to search for deviations pointing to necessary extensions or modifications of our current theoretical understanding. The top quark was predicted to exist by the Standard Model as the partner of the bottom quark. It was first observed in 1995 by the

  14. Properties of the Top Quark

    Wicke, Daniel

    2009-01-01

    The aim of particle physics is the understanding of elementary particles and their interactions. The current theory of elementary particle physics, the Standard Model, contains twelve different types of fermions which (neglecting gravity) interact through the gauge bosons of three forces. In addition a scalar particle, the Higgs boson, is needed for theoretical consistency. These few building blocks explain all experimental results found in the context of particle physics, so far. Nevertheless, it is believed that the Standard Model is only an approximation to a more complete theory. First of all the fourth known force, gravity, has withstood all attempts to be included until now. Furthermore, the Standard Model describes several features of the elementary particles like the existence of three families of fermions or the quantisation of charges, but does not explain these properties from underlying principles. Finally, the lightness of the Higgs boson needed to explain the symmetry breaking is difficult to maintain in the presence of expected corrections from gravity at high scales. This is the so called hierarchy problem. In addition astrophysical results indicate that the universe consists only to a very small fraction of matter described by the Standard Model. Large fractions of dark energy and dark matter are needed to describe the observations. Both do not have any correspondence in the Standard Model. Also the very small asymmetry between matter and anti-matter that results in the observed universe built of matter (and not of anti-matter) cannot be explained until now. It is thus an important task of experimental particle physics to test the predictions of the Standard Model to the best possible accuracy and to search for deviations pointing to necessary extensions or modifications of our current theoretical understanding. The top quark was predicted to exist by the Standard Model as the partner of the bottom quark. It was first observed in 1995 by the

  15. Heat-transfer resistance at solid-liquid interfaces: a tool for the detection of single-nucleotide polymorphisms in DNA.

    van Grinsven, Bart; Vanden Bon, Natalie; Strauven, Hannelore; Grieten, Lars; Murib, Mohammed; Monroy, Kathia L Jiménez; Janssens, Stoffel D; Haenen, Ken; Schöning, Michael J; Vermeeren, Veronique; Ameloot, Marcel; Michiels, Luc; Thoelen, Ronald; De Ceuninck, Ward; Wagner, Patrick

    2012-03-27

    In this article, we report on the heat-transfer resistance at interfaces as a novel, denaturation-based method to detect single-nucleotide polymorphisms in DNA. We observed that a molecular brush of double-stranded DNA grafted onto synthetic diamond surfaces does not notably affect the heat-transfer resistance at the solid-to-liquid interface. In contrast to this, molecular brushes of single-stranded DNA cause, surprisingly, a substantially higher heat-transfer resistance and behave like a thermally insulating layer. This effect can be utilized to identify ds-DNA melting temperatures via the switching from low- to high heat-transfer resistance. The melting temperatures identified with this method for different DNA duplexes (29 base pairs without and with built-in mutations) correlate nicely with data calculated by modeling. The method is fast, label-free (without the need for fluorescent or radioactive markers), allows for repetitive measurements, and can also be extended toward array formats. Reference measurements by confocal fluorescence microscopy and impedance spectroscopy confirm that the switching of heat-transfer resistance upon denaturation is indeed related to the thermal on-chip denaturation of DNA. © 2012 American Chemical Society

  16. Effects of dynamical quarks in UKQCD simulations

    Allton, Chris

    2002-01-01

    Recent results from the UKQCD Collaboration's dynamical simulations are presented. The main feature of these ensembles is that they have a fixed lattice spacing and volume, but varying sea quark mass from infinite (corresponding to the quenched simulation) down to roughly that of the strange quark mass. The main aim of this work is to uncover dynamical quark effects from these 'matched' ensembles. We obtain some evidence of dynamical quark effects in the static quark potential with less effects in the hadronic spectrum

  17. Heavy quarks and CP: Moriond 1985

    Bjorken, J.D.

    1985-03-01

    The presentations at the Fifth Moriond Workshop on Heavy Quarks, Flavor Mixing, and CP Violation (La Plagne, France, January 13-19, 1985) are summarized. The following topics are reviewed. What's New (beyond the top, top quarks, bottom quarks, charm quarks, strange quarks, and others); why is all this being done (strong interactions and hadron structure, and electroweak properties); and what next (facilities and can one see CP violation in the B-anti B system). 64 refs., 10 figs

  18. Study on Enhancement of Sub-Cooled Flow Boiling Heat Transfer and Critical Heat Flux of Solid-Water Two-Phase Mixture

    Yasuo Koizumi; Hiroyasu Ohtake; Tomoyuki Suzuki

    2002-01-01

    The influence of particle introduction into a subcooled water flow on boiling heat transfer and critical heat flux (CHF) was examined. When the water velocity was low, the particles crowded on the bottom wall of the flow channel and flowed just like sliding on the wall. When the water velocity was high, the particles were well dispersed in the water flow. In the non-boiling region, the heat transfer was augmented by the introduction of the particles into the water flow. As the introduction of the particles were increased, the augmentation was also increased in the high water flow rate region. However, it was independent upon the particle introduction rate in the low water flow rate region. The onset of boiling was delayed by the particle inclusion. The boiling heat transfer was enhanced by the particles. However, it was rather decreased in the high heat flux fully-developed-boiling region. The CHF was decreased by the particle inclusion in the low water flow region and was not affected in the high water flow region. (authors)

  19. Quark effects in nuclear physics

    Scholten, O.

    1990-01-01

    The magnitude of the quark effect for low-energy nuclear physics is investigated. Coulomb energy is studied in the A=3 system in order to determine the effect of the composite structure of the nucleon. In the actual calculations a non-relativistic quark-cluster model description has been used. A nucleon size b=0.617 fm, the width of the relative wave function Φ of the quarks in the nucleon, has been assumed. It is concluded that the contribution to Coulomb energies due to quark effects are significant compared to the observed Nolen-Schiffer anomaly. However these do not provide the long searched for 'smoking gun'. When the free parameters that appear in the calculation are adjusted to reproduce the same charge form factor, the calculated anomalies are not significantly different. 2 figs., 2 tabs., 8 refs.2

  20. Heavy quark and magnetic moment

    Mubarak, Ahmad; Jallu, M.S.

    1979-01-01

    The magnetic moments and transition moments of heavy hadrons including the conventional particles are obtained under the SU(5) truth symmetry scheme. To this end state vectors are defined and the quark additivity principle is taken into account. (author)

  1. Quark potential of spontaneous strings

    German, G.; Kleinert, H.

    1989-01-01

    The authors present some recent developments in string models with an extrinsic curvature term in action. Particular emphasis is placed upon the static quark potential and on the thermal deconfinement properties of spontaneous strings

  2. Top quark properties at ATLAS

    Dilip, Jana

    2008-01-01

    The ATLAS potential for the study of the top quark properties and physics beyond the Standard Model in the top quark sector, is described. The measurements of the top quark charge, the spin and spin correlations, the Standard Model decay (t-> bW), rare top quark decays associated to flavour changing neutral currents (t-> qX with X = gluon, Z, photon) and ttbar resonances are discussed. The sensitivity of the ATLAS experiment is estimated for an expected luminosity of 1fb-1 at the LHC. The full simulation of the ATLAS detector is used. For the Standard Model measurements the expected precision is presented. For the tests of physics beyond the Standard Model, the 5 sigma discovery potential (in the presence of a signal) and the 95% Confidence Level (CL) limit (in the absence of a signal) are given.

  3. Top Quark Physics with CMS

    CERN. Geneva

    2011-01-01

    Higgs mechanism. There are various hints at deviations from the Standard Model expectation which have been observed recently by Tevatron experiments in top final states. Several signatures of new physics accessible at the LHC either suffer from top-quark production as a significant background or contain top quarks themselves. In this talk, we present results on top quark physics obtained from the first LHC data collected by the CMS experiment.They include measurements of the top pair production cross section in various channels and their combination, measurements of the top quark mass, the single top cross section, a search for new particles decaying into top pairs, and a first look at the charge asymmetry.

  4. Lab cooks up quark soup

    Dumé, Belle

    2003-01-01

    "Physicists working at the Relativistic Heavy Ion Collider (RHIC) at the Brookhaven National Laboratory in the US say that they have come closer than ever before to creating a quark-gluon plasma" (0.5 page)

  5. Colour screening and quark confinement

    Mack, G.

    1978-03-01

    It is proposed that in Quantum Chromodynamics the colour charge of gluons and of anything with zero triality is screened by a dynamical Higgs mechanism with Higgs scalars made out of gluons. The center Z 3 of the gauge group SU(3) is left unbroken in this way, and single quarks, which have nonzero triality, cannot be screened. Long range forces between them persist therefore. Given that the Higgs mechanism produces a mass gap, the most favorable configuration of field lines between e.g. quark and antiquark will be in strings analogous to magnetic field lines in a superconductor. The strings confine the quarks. The screening mechanism, on the other hand, produces not only the mass gap (which leads to string formation) but is also responsible for saturation of forces, i.e. absence of bound states of six quarks etc. (orig.) [de

  6. Colour screening and quark confinement

    Mack, G.

    1978-01-01

    It is proposed that in quantum chromodynamics the colour charge of gluons and of anything with zero triality is screened by a dynamic Higgs mechanism with Higgs scalars made out of gluons, but the center Z 3 of the gauge group SU(3) is left unbroken, and single quarks, which have nonzero triality, are not screened. Long range forces between them persist therefore. Given that the Higgs mechanism produces a mass gap, the most favourable configuration of field lines between e.g., quark and antiquark will be in strings analogous to magnetic field lines in a superconductor. The string confine the quarks. The screening mechanism, on the other hand, produces not only the mass gap (which leads to string formation) but is also responsible for saturation of forces, i.e. absence of bound states of six quarks, etc. (Auth.)

  7. Thermodynamic modeling and evaluation of high efficiency heat pipe integrated biomass Gasifier–Solid Oxide Fuel Cells–Gas Turbine systems

    Santhanam, S.; Schilt, C.; Turker, B.; Woudstra, T.; Aravind, P.V.

    2016-01-01

    This study deals with the thermodynamic modeling of biomass Gasifier–SOFC (Solid Oxide Fuel Cell)–GT (Gas Turbine) systems on a small scale (100 kW_e). Evaluation of an existing biomass Gasifier–SOFC–GT system shows highest exergy losses in the gasifier, gas turbine and as waste heat. In order to reduce the exergy losses and increase the system's efficiency, improvements are suggested and the effects are analyzed. Changing the gasifying agent for air to anode gas gave the largest increase in the electrical efficiency. However, heat is required for an allothermal gasification to take place. A new and simple strategy for heat pipe integration is proposed, with heat pipes placed in between stacks in series, rather than the widely considered approach of integrating the heat pipes within the SOFC stacks. The developed system based on a Gasifier–SOFC–GT combination improved with heat pipes and anode gas recirculation, increases the electrical efficiency from approximately 55%–72%, mainly due to reduced exergy losses in the gasifier. Analysis of the improved system shows that operating the system at possibly higher operating pressures, yield higher efficiencies within the range of the operating pressures studied. Further the system was scaled up with an additional bottoming cycle achieved electrical efficiency of 73.61%. - Highlights: • A new and simple strategy for heat pipe integration between SOFC and Gasifier is proposed. • Anode exhaust gas is used as a gasifying agent. • The new proposed Gasifier–SOFC–GT system achieves electrical efficiency of 72%. • Addition of steam rankine bottoming cycle to proposed system increases electrical efficiency to 73.61%.

  8. Quark nuclear physics at JHF

    Toki, H.

    2000-01-01

    We discuss the research fields to be studied by the Japan Hadron Facility being planned in the site of JAERI as a joint project with Neutron Science Project. We would expect to reveal the most microscopic structure of matter using the intensity frontier proton machine. In particular, we would like to develop Quark Nuclear Physics to describe hadrons and nuclei in terms of quarks and gluons. (author)

  9. Heavy quark production and spectroscopy

    Appel, J.A.

    1993-11-01

    This review covers many new experimental results on heavy flavor production and spectroscopy. It also shows some of the increasingly improved theoretical understanding of results in light of basic perturbative QCD and heavy quark symmetry. At the same time, there are some remaining discrepancies among experiments as well as significant missing information on some of the anticipated lowest lying heavy quark states. Most interesting, perhaps, are some clearly measured production effects awaiting full explanation

  10. Quark effects in nuclear structure

    Watt, A.

    1987-01-01

    Some experimental data in nuclear structure physics cannot be explained on the assumption that nuclei consist of inert protons and neutrons. The quark model attributes a definite internal structure to nucleons and implies that their properties should change when embedded in a nucleus. This article reviews some of the experimental evidence for these effects and discusses some new aspects of nuclear structure predicted by the quark model

  11. Sextet quarks and light pseudoscalars

    Clark, T.E.; Leung, C.N.; Love, S.T.; Rosner, J.L.; Chicago Univ., IL

    1986-01-01

    Light pseudoscalar bosons are a very general consequence of the existence of higher-color representations (such as sextets) of quarks. It is shown that if the condensate vertical stroke vertical stroke=F 3 defines a scale F>>Λ QCD , as has been expected on the basis of perturbative and lattice calculations, then present limits on axions exclude a wide range of values of F. Such limits therefore serve as complements to direct accelerator searches for higher-color quarks. (orig.)

  12. Polarization in heavy quark decays

    Alimujiang, K.

    2006-07-01

    In this thesis I concentrate on the angular correlations in top quark decays and their next.to.leading order (NLO) QCD corrections. I also discuss the leading.order (LO) angular correlations in unpolarized and polarized hyperon decays. In the first part of the thesis I calculate the angular correlation between the top quark spin and the momentum of decay products in the rest frame decay of a polarized top quark into a charged Higgs boson and a bottom quark in Two-Higgs-Doublet-Models: t({up_arrow}) {yields} b + H{sup +}. I provide closed form formulae for the O({alpha}{sub s}) radiative corrections to the unpolarized and the polar correlation functions for m{sub b}{ne}0 and m{sub b}=0. In the second part I concentrate on the semileptonic rest frame decay of a polarized top quark into a bottom quark and a lepton pair: t({up_arrow}){yields}X{sub b}+l{sup +}+{nu}{sub l}. I present closed form expressions for the O({alpha}{sub s}) radiative corrections to the unpolarized part and the polar and azimuthal correlations for m{sub b}{ne}0 and m{sub b}=0. In the last part I turn to the angular distribution in semileptonic hyperon decays. Using the helicity method I derive complete formulas for the leading order joint angular decay distributions occurring in semileptonic hyperon decays including lepton mass and polarization effects. (orig.)

  13. Modeling of hydrogen/deuterium dynamics and heat generation on palladium nanoparticles for hydrogen storage and solid-state nuclear fusion

    Katsuaki Tanabe

    2016-01-01

    Full Text Available We modeled the dynamics of hydrogen and deuterium adsorbed on palladium nanoparticles including the heat generation induced by the chemical adsorption and desorption, as well as palladium-catalyzed reactions. Our calculations based on the proposed model reproduce the experimental time-evolution of pressure and temperature with a single set of fitting parameters for hydrogen and deuterium injection. The model we generated with a highly generalized set of formulations can be applied for any combination of a gas species and a catalytic adsorbent/absorbent. Our model can be used as a basis for future research into hydrogen storage and solid-state nuclear fusion technologies.

  14. Modeling of hydrogen/deuterium dynamics and heat generation on palladium nanoparticles for hydrogen storage and solid-state nuclear fusion.

    Tanabe, Katsuaki

    2016-01-01

    We modeled the dynamics of hydrogen and deuterium adsorbed on palladium nanoparticles including the heat generation induced by the chemical adsorption and desorption, as well as palladium-catalyzed reactions. Our calculations based on the proposed model reproduce the experimental time-evolution of pressure and temperature with a single set of fitting parameters for hydrogen and deuterium injection. The model we generated with a highly generalized set of formulations can be applied for any combination of a gas species and a catalytic adsorbent/absorbent. Our model can be used as a basis for future research into hydrogen storage and solid-state nuclear fusion technologies.

  15. Quark-diquark approximation of the three-quark structure of baryons in the quark confinement model

    Efimov, G.V.; Ivanov, M.A.; Lyubovitskij, V.E.

    1990-01-01

    Octet (1 + /2) and decuplet (3 + /2) of baryons as relativistic three-quark states are investigated in the quark confinement model (QCM), the relativistic quark model, based on some assumptions about hadronization and quark confinement. The quark-diquark approximation of the three-quark structure of baryons is proposed. In the framework of this approach the description of the main low-energy characteristics of baryons as magnetic moments, electromagnetic radii and form factors, ratio of axial and vector constants in semileptonic baryon octet decays, strong form factors and decay widths is given. The obtained results are in agreement with experimental data. 31 refs.; 4 figs.; 5 tabs

  16. 1 Hz fast-heating fusion driver HAMA pumped by a 10 J green diode-pumped solid-state laser

    Mori, Y.; Komeda, O.; Nakayama, S.; Ishii, K.; Hanayama, R.; Fujita, K.; Okihara, S.; Sekine, T.; Satoh, N.; Kurita, T.; Kawashima, T.; Kan, H.; Nakamura, N.; Kondo, T.; Fujine, M.; Azuma, H.; Hioki, T.; Kakeno, M.; Motohiro, T.; Nishimura, Y.

    2013-01-01

    A Ti : sapphire laser HAMA pumped by a diode-pumped solid-state laser (DPSSL) is developed to enable a high-repetitive inertial confinement fusion (ICF) experiment to be conducted. To demonstrate a counter-irradiation fast-heating fusion scheme, a 3.8 J, 0.4 ns amplified chirped pulse is divided into four beams: two counter-irradiate a target with intensities of 6 × 10 13 W cm −2 , and the remaining two are pulse-compressed to 110 fs for heating the imploded target with intensities of 2 × 10 17 W cm −2 . HAMA contributed to the first demonstration by showing that a 10 J class DPSSL is adaptable to ICF experiments and succeeded in DD neutron generation in the repetition mode. Based on HAMA, we can design and develop an integrated repetitive ICF experiment machine by including target injection and tracking. (paper)

  17. The abundant excess heat production during low energy nuclear reaction in the nano scale solid state the cold fusion, 14 years' legacy

    Woo, Tae Ho; Miley, George H.; Lipson, Andrei; Kim, Sung O.; Luo, Nie; Castano, Carlos H.

    2002-01-01

    The quite abundant excess heat and radioactive materials are found during the solid state reaction. This phenomenon has done during the Low Energy Nuclear Reaction (LENR) in the nano scale molecular structure electrodes and Hydrogen compound electrolytes. The Palladium (or Nickel) and Platinum are incorporated as the electrode and the Light Water (H 2 O) as the electrolyte. The excess heat was produced up to 40% in year 2001. The Alpha particles are also detected. The computer code, Coherent Lattice Accelerator Inter-Ionic Reaction Enhancer (CLAIRE) Code System, is constructed for the simulation. The 0.1 A of the distance between two the Hydrogen ion (proton) and Palladium nucleus is the critical point for the nuclear fusion reaction

  18. The abundant excess heat production during low energy nuclear reaction in the nano scale solid state the cold fusion, 14 years' legacy

    Woo, Tae Ho; Miley, George H.; Lipson, Andrei; Kim, Sung O.; Luo, Nie; Castano, Carlos H. [The University of Illinois, Urbana (United States)

    2002-05-01

    The quite abundant excess heat and radioactive materials are found during the solid state reaction. This phenomenon has done during the Low Energy Nuclear Reaction (LENR) in the nano scale molecular structure electrodes and Hydrogen compound electrolytes. The Palladium (or Nickel) and Platinum are incorporated as the electrode and the Light Water (H{sub 2}O) as the electrolyte. The excess heat was produced up to 40% in year 2001. The Alpha particles are also detected. The computer code, Coherent Lattice Accelerator Inter-Ionic Reaction Enhancer (CLAIRE) Code System, is constructed for the simulation. The 0.1 A of the distance between two the Hydrogen ion (proton) and Palladium nucleus is the critical point for the nuclear fusion reaction.

  19. Reforming processes for micro combined heat and powersystem based on solid oxide fuel cell

    Liso, Vincenzo; Nielsen, Mads Pagh; Kær, Søren Knudsen

    2009-01-01

    Solid oxide fuel cell (SOFC) is a promising technology for decentralized power generation and cogeneration. This technology has several advantages: the high electric efficiency, which can be theoretically improved through integration in power cycles; the low emissions; and the possibility of using...... a large variety of gaseous fuels. The high operating temperature (700-1000°C) of SOFCs has a number of consequences, the most important of which are the possibility to partially reform the raw fuel in the fuel cell anode compartment and the possibility to use high quality heat for cogeneration....... In this work, different configurations of SOFC systems for decentralized electricity production are considered and studied. The balance of plant (BoP) components will be identified including fuel and air supply, fuel management, start-up steam, anode re-circulation, exhaust gas heat management, power...

  20. Composite quarks and their magnetic moments

    Parthasarathy, R.

    1980-08-01

    A composite quark model based on the symmetry group SU(10)sub(flavour) x SU(10)sub(colour) with the assumption of mass non-degenerate sub-quarks is considered. Magnetic moments of quarks and sub-quarks are obtained from the observed nucleon magnetic moments. Using these quark and sub-quark magnetic moments, a satisfactory agreement for the radiative decays of vector mesons (rho,ω) is obtained. The ratio of the masses of the sub-quarks constituting the u,d,s quarks are found to be Msub(p)/Msub(n) = 0.3953 and Msub(p)/Msub(lambda) = 0.596, indicating a mass hierarchy Msub(p) < Msub(n) < Msub(lambda) for the sub-quarks. (author)

  1. Top quark production at the LHC

    Gilles, Geoffrey; The ATLAS collaboration

    2018-01-01

    The top quark is the heaviest known fundamental particle. As it is the only quark that decays before it hadronizes, it gives us the unique opportunity to probe the properties of bare quarks at the Large Hadron Collider. This talk will present highlights of a few recent precision measurements of the top quark using 13 TeV and 8 TeV collision data: top-quark pair and single top production cross sections, including differential distributions and production in association with bosons, will be presented alongside top quark properties measurements. These measurements, including results using boosted top quarks, probe our understanding of top quark production in the TeV regime. Measurements of the top quark mass are also presented.

  2. Quarks and leptons

    Harari, H.

    1977-01-01

    The physics of quarks and leptons within the framework of gauge theories for the weak and electromagnetic interactions is reviewed. The Weinberg-Salam SU(2)xU(1) theory is used as a ''reference point'' but models based on larger gauge groups, especially SU(2)sub(L)xSU(2)sub(R)xU(1), are discussed. We distinguish among three ''Generations'' of fundamental fermions: The first generation (e - , νsub(e), u, d), the second generation (μ - , νsub(μ), c, s) and the third generation (tau - , νsub(tau), t, b). For each generation are discussed the classification of all fermions, the charged and neutral weak currents, possible right-handed currents, parity and CP-violation, fermion masses and Cabibbo-like angles and related problems. Theoretical ideas as well as experimental evidence, emphasizing open theoretical problems and possible experimental tests are reviewed, as well as the possibility of unifying the weak, electromagnetic and strong interactions in a grand unification scheme. The problems and their possible solutions are presented, generation by generation, but a brief subject-index (following the table of contents) enbales the interested reader to follow any specific topic throughout the three generations. (author)

  3. Heavy quarks in proton

    AUTHOR|(SzGeCERN)655637

    The measurement of prompt photon associated with a b jet in proton-proton interactions can provide us insight into the inner structure of proton. This is because precision of determination of parton distribution functions of b quark and gluon can be increased by such a measurement. The measurement of cross-section of prompt photon associated with a b jet (process $pp\\longrightarrow \\gamma + b + X$) at $\\sqrt{s}$= 8 TeV with the ATLAS detector is presented. Full 8 TeV dataset collected by ATLAS during the year 2012 was used in this analysis. Corresponding integrated luminosity is 20.3 $fb^{-1}$. Fiducial differential cross-section as a function of photon transverse momentum at particle level was extracted from data and compared with the prediction of leading order event generator Pythia 8. Cross-section extracted from data is normalised independently on the Monte Carlo prediction. Values of data distribution lie above Monte Carlo values. The difference can be explained by presence of higher order effects not ...

  4. Modeling and simulation of a novel 4.5 kW_e multi-stack solid-oxide fuel cell prototype assembly for combined heat and power

    Anyenya, Gladys A.; Sullivan, Neal P.; Braun, Robert J.

    2017-01-01

    Highlights: • A novel CHP application of SOFC technology in unconventional oil and gas processing. • Thermo-electrochemical performance model of a multi-stack solid-oxide fuel cell (SOFC) assembly is described. • Parametric study explores a wider range of operating conditions than can be experimentally tested. • Geothermic Fuel Cell operational characteristics are reviewed. - Abstract: The United States Geological Survey estimates that over four trillion barrels of crude oil are currently trapped within U.S. oil shale reserves. However, no cost-effective, environmentally sustainable method for oil production from oil shale currently exists. Given the continuing demand for low-cost fossil-fuel production, alternative methods for shale-oil extraction are needed. Geothermic Fuel Cells™ (GFC) harness the heat generated by high-temperature solid oxide fuel cells during electricity generation to process oil shale into “sweet” crude oil. In this paper, a thermo-electrochemical model is exercised to simulate the performance of a 4.5 kW_e (gross) Geothermic Fuel Cell module for in situ oil-shale processing. The GFC analyzed in this work is a prototype which contains three 1.5 kW_e solid oxide fuel cell (SOFC) stack-and-combustor assemblies packaged within a 0.3 m diameter, 1.8 m tall, stainless-steel housing. The high-temperature process heat produced by the SOFCs during electricity generation is used to retort oil shale within underground geological formations into high-value shale oil and natural gas. A steady-state system model is developed in Aspen Plus™ using user-defined subroutines to predict the stack electrochemical performance and the heat-rejection from the module. The model is validated against empirical data from independent single-stack performance testing and full GFC-module experiments. Following model validation, further simulations are performed for different values of current, fuel and air utilization to study their influence on system

  5. Effects of magnesium-based hydrogen storage materials on the thermal decomposition, burning rate, and explosive heat of ammonium perchlorate-based composite solid propellant.

    Liu, Leili; Li, Jie; Zhang, Lingyao; Tian, Siyu

    2018-01-15

    MgH 2 , Mg 2 NiH 4 , and Mg 2 CuH 3 were prepared, and their structure and hydrogen storage properties were determined through X-ray photoelectron spectroscopy and thermal analyzer. The effects of MgH 2 , Mg 2 NiH 4 , and Mg 2 CuH 3 on the thermal decomposition, burning rate, and explosive heat of ammonium perchlorate-based composite solid propellant were subsequently studied. Results indicated that MgH 2 , Mg 2 NiH 4 , and Mg 2 CuH 3 can decrease the thermal decomposition peak temperature and increase the total released heat of decomposition. These compounds can improve the effect of thermal decomposition of the propellant. The burning rates of the propellant increased using Mg-based hydrogen storage materials as promoter. The burning rates of the propellant also increased using MgH 2 instead of Al in the propellant, but its explosive heat was not enlarged. Nonetheless, the combustion heat of MgH 2 was higher than that of Al. A possible mechanism was thus proposed. Copyright © 2017. Published by Elsevier B.V.

  6. Simultaneous fluid-flow, heat-transfer and solid-stress computation in a single computer code

    Spalding, D B [Concentration Heat and Momentum Ltd, London (United Kingdom)

    1998-12-31

    Computer simulation of flow- and thermally-induced stresses in mechanical-equipment assemblies has, in the past, required the use of two distinct software packages, one to determine the forces and the temperatures, and the other to compute the resultant stresses. The present paper describes how a single computer program can perform both tasks at the same time. The technique relies on the similarity of the equations governing velocity distributions in fluids to those governing displacements in solids. The same SIMPLE-like algorithm is used for solving both. Applications to 1-, 2- and 3-dimensional situations are presented. It is further suggested that Solid-Fluid-Thermal, ie SFT analysis may come to replace CFD on the one hand and the analysis of stresses in solids on the other, by performing the functions of both. (author) 7 refs.

  7. Simultaneous fluid-flow, heat-transfer and solid-stress computation in a single computer code

    Spalding, D.B. [Concentration Heat and Momentum Ltd, London (United Kingdom)

    1997-12-31

    Computer simulation of flow- and thermally-induced stresses in mechanical-equipment assemblies has, in the past, required the use of two distinct software packages, one to determine the forces and the temperatures, and the other to compute the resultant stresses. The present paper describes how a single computer program can perform both tasks at the same time. The technique relies on the similarity of the equations governing velocity distributions in fluids to those governing displacements in solids. The same SIMPLE-like algorithm is used for solving both. Applications to 1-, 2- and 3-dimensional situations are presented. It is further suggested that Solid-Fluid-Thermal, ie SFT analysis may come to replace CFD on the one hand and the analysis of stresses in solids on the other, by performing the functions of both. (author) 7 refs.

  8. Inclusive production of large-p/sub T/ protons and quark-quark elastic scattering

    Chen, C.K.

    1978-01-01

    A proton-formation process in combination with hard quark-quark scattering is capable of explaining the observed large-p/sub T/ single-proton inclusive production data. This model implies that the inclusive production of two large-p/sub T/ protons at opposite directions is dominated by large-angle elastic scattering of two up quarks, and becomes an ideal place to study elastic quark-quark scattering. This two-proton inclusive production process is also ideal for the study of the spin structure of quark-quark elastic scattering, so the assumptions of pure vector-type quark-quark interaction and of colored quarks can be checked empirically. The consistency of applying the quark-elastic-scattering idea to large-angle elastic proton-proton scattering and to the inclusive production of large-p/sub T/ protons is also demonstrated

  9. Heavy quark energy loss in nuclear medium

    Zhang, Benr-Wei; Wang, Enke; Wang, Xin-Nian

    2003-01-01

    Multiple scattering, modified fragmentation functions and radiative energy loss of a heavy quark propagating in a nuclear medium are investigated in perturbative QCD. Because of the quark mass dependence of the gluon formation time, the medium size dependence of heavy quark energy loss is found to change from a linear to a quadratic form when the initial energy and momentum scale are increased relative to the quark mass. The radiative energy loss is also significantly suppressed relative to a light quark due to the suppression of collinear gluon emission by a heavy quark

  10. Strange Quark Matter Status and Prospects

    Sandweiss, J.

    2004-01-01

    The existence of quark states with more than three quarks is allowed in QCD. The stability of such quark matter states has been studied with lattice QCD and phenomenological bag models, but is not well constrained by theory. The addition of strange quarks to the system allows the quarks to be in lower energy states despite the additional mass penalty. There is additional stability from reduced Coulomb repulsion. SQM is expected to have a low Z/A. Stable or metastable massive multiquark states contain u, d, and s quarks.

  11. Searches for new heavy quarks in ATLAS

    Nikiforou, Nikiforos; The ATLAS collaboration

    2018-01-01

    A search for new heavy quarks focusing on recent vector-like quark searches with the ATLAS detector at the CERN Large Hadron Collider is presented. Two recent searches targeting the pair production of type vector-like quarks are described. The first search is sensitive to vector-like up-type quark (T ) decays to a t quark and either a Standard Model Higgs boson or a Z boson. The second search is primarily sensitive to T decays to W boson and a b quark. Additionally, the results can be interpreted for alternative VLQ decays.

  12. Nuclear matter from effective quark-quark interaction.

    Baldo, M; Fukukawa, K

    2014-12-12

    We study neutron matter and symmetric nuclear matter with the quark-meson model for the two-nucleon interaction. The Bethe-Bruckner-Goldstone many-body theory is used to describe the correlations up to the three hole-line approximation with no extra parameters. At variance with other nonrelativistic realistic interactions, the three hole-line contribution turns out to be non-negligible and to have a substantial saturation effect. The saturation point of nuclear matter, the compressibility, the symmetry energy, and its slope are within the phenomenological constraints. Since the interaction also reproduces fairly well the properties of the three-nucleon system, these results indicate that the explicit introduction of the quark degrees of freedom within the considered constituent quark model is expected to reduce the role of three-body forces.

  13. Kaon quark distribution functions in the chiral constituent quark model

    Watanabe, Akira; Sawada, Takahiro; Kao, Chung Wen

    2018-04-01

    We investigate the valence u and s ¯ quark distribution functions of the K+ meson, vK (u )(x ,Q2) and vK (s ¯)(x ,Q2), in the framework of the chiral constituent quark model. We judiciously choose the bare distributions at the initial scale to generate the dressed distributions at the higher scale, considering the meson cloud effects and the QCD evolution, which agree with the phenomenologically satisfactory valence quark distribution of the pion and the experimental data of the ratio vK (u )(x ,Q2)/vπ (u )(x ,Q2) . We show how the meson cloud effects affect the bare distribution functions in detail. We find that a smaller S U (3 ) flavor symmetry breaking effect is observed, compared with results of the preceding studies based on other approaches.

  14. A model for radiative heat transfer in mixtures of a hot solid or molten material with water and steam

    Vaeth, L.

    1997-05-01

    A model has been devised for describing the radiative heat transfer in mixtures of a hot radiant material with water and steam, to be used, e.g., in the framework of a multiphase, multicomponent flow simulation. The main features of the model are: 1. The radiative heat transfer is modelled for a homogeneous mixture of one continuous material with droplets/bubbles of the other two, of the kind normally assumed for the material distribution in one cell of a bigger calculational problem. Neither the heat transfer over the cell boundaries nor the finite dimensions of the cell are taken into account. 2. The geometry of the mixture (radiant material continuous or discontinuous, droplet/bubble diameters and number densities) is taken into account. 3. The optical properties of water and water vapour are modelled as functions of the temperature of the radiant and, in the case of water vapour, also of the absorbing material. 4. The model distinguishes between heat transfer to the surface of the water (leading to evaporation) and into the bulk of the water (pure heating). (orig./DG) [de

  15. Spin effects in high energy quark-quark scattering

    Goloskokov, S.V.; Selyugin, O.V.

    1993-01-01

    The spin amplitudes in high-energy quark-quark scattering at /t/>1 GeV 2 are analyzed. It is shown that the gluon contributions in the QCDα s 3 order lead to the spin-flip amplitude growing as s. This means the existence of the spin-flip part in pomeron exchange. The resulting T f is about few per cent of the spin-non-flip contribution. The factorization of the large-distance and high-energy effects in the spin-flip amplitude is obtained. 13 refs.; 2 figs.; 1 tab

  16. Electronic contributions to the transport properties and specific heat of solid UO2: an empirical, self-consistent analysis

    Hyland, G.J.; Ralph, J.

    1982-07-01

    From an empirical, self-consistent analysis of new high temperature data on the thermo-electric Seebeck coefficient and d.c. electrical conductivity, the value of the free energy controlling the equilibrium of the thermally induced reaction, 2U 4+ reversible U 3+ + U 5+ is determined (treating the U 3+ and U 5+ as small polarons) and used to calculate the contribution of the process to the high temperature thermal conductivity and specific heat of UO 2 . It is found that the transport properties can be completely accounted for in this way, but not the anomalous rise in specific heat - the origin of which remains obscure. (U.K.)

  17. Physical properties and component contents of brown coal tars obtained in semicoking with a solid heat transfer semicoke

    Kuznetsov, V I; Bobrova, A A

    1955-01-01

    Tar obtained in low-temperature carbonization of brown coals with brown-coal semicoke as a heat-transfer medium contains more water and dust, has a lower drop point, and a higher specific gravity, and contains more asphaltene and less paraffin than does tar from the same coal produced in rotating retorts or in shaft kilns. The brown-coal semicoke used as a heat-transfer medium produces partial thermal cracking of the fuel and polymerization of the products of secondary decompositions. The yield of asphaltenes is lowered when the carbonization temperature is raised.

  18. Theoretical study on volatile organic compound removal and energy performance of a novel heat pump assisted solid desiccant cooling system

    Nie, Jinzhe; Fang, Lei; Zhang, Ge

    2015-01-01

    for cooling, dehumidification and indoor air cleaning in normal office, commercial or residential buildings. The desiccant rotor was used for dehumidification and indoor air cleaning; the heat pump provided sensible cooling and regeneration heat for the desiccant rotor. The theoretical model consisted of two...... and predicted. The theoretical model was validated by experimental data. Validating results showed that the model could be used to predict the performance of HP-SDC. The results also showed that the HP-SDC could clean air borne contaminants effectively and could provide an energy efficient choice...

  19. Quark exchange and nuclear dynamics

    Moniz, E.J.

    1985-01-01

    This paper gives a qualitative understanding of hadronic phenomena in terms of quark degrees of freedom. The basic model which incorporates saturating confining interactions and the study of hadron-hadron scattering has been carried through in collaboration with F. Lenz, J.T. Londergan, R. Rosenfelder, M. Stingl and K. Yazaki. It is shown that minimal confining dynamics together with exchange symmetry indeed leads to a remarkable range of phenomena at both the nuclear and particle energy scales. Most observables are well described by an effective hadron theory, the quark momentum distribution being the major exception. These features emerge even in the simplest model, namely, U(1) color and hadrons composed of two quarks (anti qq or qq). The author concentrates here on this model. In the concluding section, he remarks on the SU(N) results, particularly on the extent to which the color-hidden dynamics are constrained by examining the systematics of nuclear and hadronic phenomena. (Auth.)

  20. Compositeness of quarks and leptons

    Peskin, M.E.

    1981-01-01

    I review along grand lines the theoretical ideas associated with the notion that quarks and leptons are composite. I first discuss various constituent pictures which have been proposed to account for the quantum numbers of the observed quarks and leptons, a study I call the Quantum Numerology. I then discuss some new theoretical developments of the past two years which bear on the subject of composite fermions and which make plausible (or rule out) some of the major dynamical assumptions of these constituent models. Finally, I discuss the consequences of the compositeness of quarks and leptons by setting up a series of scenarios for this compositeness and exploring, for each scenario, its experimental implications. (orig./HSI)

  1. Measuring the sea quark polarization

    Makdisi, Y.

    1993-01-01

    Spin is a fundamental degree of freedom and measuring the spin structure functions of the nucleon should be a basic endeavor for hadron physics. Polarization experiments have been the domain of fixed target experiments. Over the years large transverse asymmetries have been observed where the prevailing QCD theories predicted little or no asymmetries, and conversely the latest deep inelastic scattering experiments of polarized leptons from polarized targets point to the possibility that little of the nucleon spin is carried by the valence quarks. The possibility of colliding high luminosity polarized proton beams in the Brookhaven Relativistic Heavy Ion Collider (RHIC) provides a great opportunity to extend these studies and systematically probe the spin dependent parton distributions specially to those reactions that are inaccessible to current experiments. This presentation focuses on the measurement of sea quark and possibly the strange quark polarization utilizing the approved RHIC detectors

  2. Waves in magnetized quark matter

    Fogaça, D. A.; Sanches, S. M.; Navarra, F. S.

    2018-05-01

    We study wave propagation in a non-relativistic cold quark-gluon plasma immersed in a constant magnetic field. Starting from the Euler equation we derive linear wave equations and investigate their stability and causality. We use a generic form for the equation of state, the EOS derived from the MIT bag model and also a variant of the this model which includes gluon degrees of freedom. The results of this analysis may be relevant for perturbations propagating through the quark matter phase in the core of compact stars and also for perturbations propagating in the low temperature quark-gluon plasma formed in low energy heavy ion collisions, to be carried out at FAIR and NICA.

  3. Heavy quark spectroscopy and decay

    Schindler, R.H.

    1987-01-01

    The understanding of q anti q systems containing heavy, charmed, and bottom quarks has progressed rapidly in recent years, through steady improvements in experimental techniques for production and detection of their decays. These lectures are meant to be an experimentalist's review of the subject. In the first of two lectures, the existing data on the spectroscopy of the bound c anti c and b anti b systems will be discussed. Emphasis is placed on comparisons with the theoretical models. The second lecture covers the rapidly changing subject of the decays of heavy mesons (c anti q and b anti q), and their excited states. In combination, the spectroscopy and decays of heavy quarks are shown to provide interesting insights into both the strong and electroweak interactions of the heavy quarks. 103 refs., 39 figs

  4. Quark matter brings heavy ions to Oakland

    Klein, Spencer; Nystrand, Joakim

    2004-01-01

    The Quark Matter 2004 conference, held in Oakland, California, in January, provided participants with evidence for the elusive quark-gluon plasma. Spencer Klein and Joakim Nystrand describe the highlights of the meeting

  5. On the Coulomb gauge quark propagator

    Kloker, M.; Alkofer, R.; Krassnigg, A.; Krenn, R.

    2006-01-01

    Full text: A solution of the quark Dyson-Schwinger equation including transverse gluons is presented. The corresponding retardation effects in the quark propagator are discussed. Especially, their effects on confinement properties and dynamical mass generation are described. (author)

  6. Quark degrees of freedom in compact stars

    Marranghello, G.F.; Vasconcellos, C.A.Z. [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Inst. de Fisica. Dept. de Fisica; Hadjimichef, D. [Pelotas Univ., RS (Brazil). Inst. de Fisica e Matematica. Dept. de Fisica

    2001-07-01

    Nuclear matter may show a phase transition at high densities, where quarks and gluons are set free, forming a so called quark-gluon plasma. At the same range of densities, neutron stars are formed. In this work we have grouped both ideas in the study of the quark-gluon plasma formation inside compact stars, here treated as pure neutron star, hybrid star and pure quark matter star. (author)

  7. Quark degrees of freedom in compact stars

    Marranghello, G.F.; Vasconcellos, C.A.Z.; Hadjimichef, D.

    2001-01-01

    Nuclear matter may show a phase transition at high densities, where quarks and gluons are set free, forming a so called quark-gluon plasma. At the same range of densities, neutron stars are formed. In this work we have grouped both ideas in the study of the quark-gluon plasma formation inside compact stars, here treated as pure neutron star, hybrid star and pure quark matter star. (author)

  8. The weak conversion rate in quark matter

    Heiselberg, H.

    1992-01-01

    The weak conversion rate of strange to down quarks, s + u ↔ u + d, is calculated analytically for degenerate u, d and s quark matter to leading orders in temperature and deviations from chemical equilibrium. The rate is applied to burning of neutron matter into quark matter, to evaporation from quark nuggets in the early universe, for estimating the lifetime of strangelets, and to pulsar glitches

  9. Top quark production at the Tevatron

    Varnes, Erich W.; /Arizona U.

    2010-09-01

    The Fermilab Tevatron has, until recently, been the only accelerator with sufficient energy to produce top quarks. The CDF and D0 experiments have collected large samples of top quarks. We report on recent top quark production measurements of the single top and t{bar t} production cross sections, as well as studies of the t{bar t} invariant mass distribution and a search for highly boosted top quarks.

  10. Free-quark phases in dense stars

    Keister, B D; Kisslinger, L S [Carnegie-Mellon Univ., Pittsburgh, Pa. (USA). Dept. of Physics

    1976-08-30

    The possibility is examined that superdense matter can undergo a transition to a phase of free quarks within models which assume that the quark confinement potential is screened at high densities. The results imply that a phase of pure quarks of this type is unlikely to be found in stable stellar systems although they do not preclude the possible existence of a transition region which contains quarks and neutrons in equilibrium at the center of neutron stars.

  11. Triplicity of hadrons, quarks and subquarks

    Terazawa, Hidezumi.

    1989-11-01

    Triplicity of hadrons, quarks and subquarks asserting that a certain physical quantity such as the weak current is taken equally well as either one of a composite operator of hadrons, that of quarks and that of subquarks is proposed. Among other things, the weak mixing angle, the quark mixing matrix and the mass sum rules for quarks and leptons are revisited, reinterpreted and discussed in detail in triplicity. (author)

  12. An alternative approach to heavy quark bags

    Baacke, J.; Kasperidus, G.

    1980-01-01

    We discuss a formulation of quark bags where the quark wave function depends only on the relative coordinate and the bag boundary is fixed with respect to the center of mass of the quark system. For technical reasons we have to restrict ourselves to a heavy quark-antiquark system in an s-wave with spherical boundary. A phenomenological application to quarkonium states encourages further investigation of the approach. (orig.)

  13. Characterization of simultaneous heat and mass transfer phenomena for water vapour condensation on a solid surface in an abiotic environment--application to bioprocesses.

    Tiwari, Akhilesh; Kondjoyan, Alain; Fontaine, Jean-Pierre

    2012-07-01

    The phenomenon of heat and mass transfer by condensation of water vapour from humid air involves several key concepts in aerobic bioreactors. The high performance of bioreactors results from optimised interactions between biological processes and multiphase heat and mass transfer. Indeed in various processes such as submerged fermenters and solid-state fermenters, gas/liquid transfer need to be well controlled, as it is involved at the microorganism interface and for the control of the global process. For the theoretical prediction of such phenomena, mathematical models require heat and mass transfer coefficients. To date, very few data have been validated concerning mass transfer coefficients from humid air inflows relevant to those bioprocesses. Our study focussed on the condensation process of water vapour and developed an experimental set-up and protocol to study the velocity profiles and the mass flux on a small size horizontal flat plate in controlled environmental conditions. A closed circuit wind tunnel facility was used to control the temperature, hygrometry and hydrodynamics of the flow. The temperature of the active surface was controlled and kept isothermal below the dew point to induce condensation, by the use of thermoelectricity. The experiments were performed at ambient temperature for a relative humidity between 35-65% and for a velocity of 1.0 ms⁻¹. The obtained data are analysed and compared to available theoretical calculations on condensation mass flux.

  14. Case Study for the ARRA-funded Ground Source Heat Pump (GSHP) Demonstration at Wilders Grove Solid Waste Service Center in Raleigh, NC

    Liu, Xiaobing [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Malhotra, Mini [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Xiong, Zeyu [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-11-01

    High initial costs and lack of public awareness of ground-source heat pump (GSHP) technology are the two major barriers preventing rapid deployment of this energy-saving technology in the United States. Under the American Recovery and Reinvestment Act (ARRA), 26 GSHP projects have been competitively selected and carried out to demonstrate the benefits of GSHP systems and innovative technologies for cost reduction and/or performance improvement. This paper highlights the findings of a case study of one of the ARRA-funded GSHP demonstration projects, a distributed GSHP system for providing all the space conditioning, outdoor air ventilation, and 100% domestic hot water to the Wilders Grove Solid Waste Service Center of City of Raleigh, North Carolina. This case study is based on the analysis of measured performance data, construction costs, and simulations of the energy consumption of conventional central heating, ventilation, and air-conditioning (HVAC) systems providing the same level of space conditioning and outdoor air ventilation as the demonstrated GSHP system. The evaluated performance metrics include the energy efficiency of the heat pump equipment and the overall GSHP system, pumping performance, energy savings, carbon emission reductions, and cost-effectiveness of the GSHP system compared with conventional HVAC systems. This case study also identified opportunities for reducing uncertainties in the performance evaluation and improving the operational efficiency of the demonstrated GSHP system.

  15. Pion electromagnetic polarizabilities and quarks

    Llanta, E.; Tarrach, R.

    1980-01-01

    The electric and magnetic polarizabilities of the neutral and charged pion are calculated in a coloured quark field theory at the one-loop level. The theory has as free parameter the quark mass but our results do not depend on it. We have found that the electric polarizabilities are αsub(π+-) = -0.04 α/m 3 sub(π), αsub(π 0 ) = -0.4 α/m 3 sub(π). These values are compared with calculations in other models and some comments are made about the polarizability sum rules. (orig.)

  16. Effects of quarks in nuclei

    Rho, M.

    1983-11-01

    The issue as to whether or not quarks will manifest themselves explicitly in nuclear processes is discussed in the light of the recently discovered topological structure of the baryon. Due to the leakage of the baryon charge from a confinement region (bag) into a meson-cloud region, there emerges a sort of topological equivalence principle which renders physically equivalent the description in terms of Goldstone meson fields alone (the Skyrmion) and the description in terms of a bag (confining quarks) surrounded by a meson cloud (the chiral bag model). How this new structure will modify our understanding of the nucleon and the nucleus is examined

  17. The unconfined quarks and gluons

    Abdus Salam

    1977-01-01

    The consequences of the lepton-hadron gauge unification hypothesis with unconfined quarks and gluons being the hall-mark are discussed. Quark and gluon decays into leptons are shown to provide a new source of multileptonic production in NN, νN and μN collisions. A theorem is stated and proved which highlights the differences between the dynamics of gauge versus non-gauge 1 - particles. Empirical manifestations of gauge coloured mesons are discussed. The question of exact confinement or not is concluded to be in the end an empirical one and must be settled in the laboratory

  18. Simulating at realistic quark masses. Light quark masses

    Goeckeler, M.; Streuer, T.

    2006-11-01

    We present new results for light quark masses. The calculations are performed using two flavours of O(a) improved Wilson fermions. We have reached lattice spacings as small as a ∝0.07 fm and pion masses down to m π ∝340 MeV in our simulations. This gives us significantly better control on the chiral and continuum extrapolations. (orig.)

  19. New theoretical results in heavy quark hadroproduction

    Nason, P.

    1992-01-01

    We describe the status of the heavy quark hadroproduction theory. In particular, we discuss recent developments on production of heavy quarks in the high energy limit, and the results of a new calculation to next-to-leading accuracy of the fully exclusive parton cross section for heavy quark production. (orig.)

  20. ''Follow that quark!'' (and other exclusive stories)

    Carroll, A.S.

    1987-01-01

    Quarks are considered to be the basic constituents of matter. In a series of recent experiments, Carroll studied exclusive reactions as a means of determining the interactions between quarks. Quantum Chromo-dynamics (QCD) is the modern theory of the interaction of quarks. This theory explains how quarks are held together via the strong interaction in particles known as hadrons. Hadrons consisting of three quarks are called baryons. Hadrons made up of a quark and an antiquark are called mesons. In his lecture, Carroll describes what happens when two hadrons collide and scatter to large angles. The violence of the collision causes the gluons that bind the quarks in a particular hadron to temporarily lose their grip on particular quarks. Quarks scramble toward renewed unity with other quarks, and they undergo rearrangement, which generally results in additional new particles. A two-body exclusive reaction has occurred when the same number of particles exist before and after the collisions. At large angles these exclusive reactions are very rare. The labels on the quarks known as flavor enable the experimenter to follow the history of individual quarks in detail during these exclusive reactions. Carroll describes the equipment used in the experiment to measure short distance, hard collisions at large angles. The collisions he discusses occur when a known beam of mesons or protons collide with a stationary proton target. Finally, Carroll summarizes what the experiments have shown from the study of exclusive reactions and what light some of their results shed on the theory of QCD

  1. Quark fragmentation in e+e- collisions

    Oddone, P.

    1984-12-01

    This brief review of new results in quark and gluon fragmentation observed in e + e - collisions concentrates mostly on PEP results and, within PEP, mostly on TPC results. The new PETRA results have been reported at this conference by M. Davier. It is restricted to results on light quark fragmentation since the results on heavy quark fragmentation have been reported by J. Chapman

  2. Planar quark diagrams and binary spin processes

    Grigoryan, A.A.; Ivanov, N.Ya.

    1986-01-01

    Contributions of planar diagrams to the binary scattering processes are analyzed. The analysis is based on the predictions of quark-gluon picture of strong interactions for the coupling of reggeons with quarks as well as on the SU(6)-classification of hadrons. The dependence of contributions of nonplanar corrections on spins and quark composition of interacting particles is discussed

  3. Charm-quarks and new elementary particles

    Petersen, J.L.

    1978-01-01

    This is the first part of an extensive paper which discusses: the Nobel prize in physics 1976; discovery of the J/psi-particle; elementary particles and elementary building blocks; the four reciprocal effects; gauge theories; quark-antiquark reciprocal effects; the high-energy approximation; a simple quark-antiquark potential; and quark diagrams and the Zweig rule. (Auth.)

  4. Variational approach to chiral quark models

    Futami, Yasuhiko; Odajima, Yasuhiko; Suzuki, Akira

    1987-03-01

    A variational approach is applied to a chiral quark model to test the validity of the perturbative treatment of the pion-quark interaction based on the chiral symmetry principle. It is indispensably related to the chiral symmetry breaking radius if the pion-quark interaction can be regarded as a perturbation.

  5. A variational approach to chiral quark models

    Futami, Yasuhiko; Odajima, Yasuhiko; Suzuki, Akira.

    1987-01-01

    A variational approach is applied to a chiral quark model to test the validity of the perturbative treatment of the pion-quark interaction based on the chiral symmetry principle. It is indispensably related to the chiral symmetry breaking radius if the pion-quark interaction can be regarded as a perturbation. (author)

  6. Pole masses of quarks in dimensional reduction

    Avdeev, L.V.; Kalmykov, M.Yu.

    1997-01-01

    Pole masses of quarks in quantum chromodynamics are calculated to the two-loop order in the framework of the regularization by dimensional reduction. For the diagram with a light quark loop, the non-Euclidean asymptotic expansion is constructed with the external momentum on the mass shell of a heavy quark

  7. Thermal evolution of massive compact objects with dense quark cores

    Hess, Daniel; Sedrakian, Armen

    2011-01-01

    We examine the thermal evolution of a sequence of compact objects containing low-mass hadronic and high-mass quark-hadronic stars constructed from a microscopically motivated equation of state. The dependence of the cooling tracks in the temperature versus age plane is studied on the variations of the gaplessness parameter (the ratio of the pairing gap for red-green quarks to the electron chemical potential) and the magnitude of blue quark gap. The pairing in the red-green channel is modeled assuming an inhomogeneous superconducting phase to avoid tachionic instabilities and anomalies in the specific heat; the blue colored condensate is modeled as a Bardeen-Cooper-Schrieffer (BCS)-type color superconductor. We find that massive stars containing quark matter cool faster in the neutrino-cooling era if one of the colors (blue) is unpaired and/or the remaining colors (red-green) are paired in a inhomogeneous gapless superconducting state. The cooling curves show significant variations along the sequence, as the mass (or the central density) of the models is varied. This feature provides a handle for fine-tuning the models to fit the data on the surface temperatures of same-age neutron stars. In the late-time photon cooling era we observe inversion in the temperature arrangement of models, i.e., stars experiencing fast neutrino cooling are asymptotically hotter than their slowly cooling counterparts.

  8. Designing a miniaturised heated stage for in situ optical measurements of solid oxide fuel cell electrode surfaces, and probing the oxidation of solid oxide fuel cell anodes using in situ Raman spectroscopy

    Brightman, E.; Maher, R.; Offer, G. J.; Duboviks, V.; Heck, C.; Cohen, L. F.; Brandon, N. P.

    2012-01-01

    A novel miniaturised heated stage for in operando optical measurements on solid oxide fuel cell electrode surfaces is described. The design combines the advantages of previously reported designs, namely, (i) fully controllable dual atmosphere operation enabling fuel cell pellets to be tested in operando with either electrode in any atmosphere being the focus of study, and (ii) combined electrochemical measurements with optical spectroscopy measurements with the potential for highly detailed study of electrochemical processes; with the following advances, (iii) integrated fitting for mounting on a mapping stage enabling 2-D spatial characterisation of the surface, (iv) a compact profile that is externally cooled, enabling operation on an existing microscope without the need for specialized lenses, (v) the ability to cool very rapidly, from 600 °C to 300 °C in less than 5 min without damaging the experimental apparatus, and (vi) the ability to accommodate a range of pellet sizes and thicknesses. © 2012 American Institute of Physics.

  9. High order ADER schemes for a unified first order hyperbolic formulation of continuum mechanics: Viscous heat-conducting fluids and elastic solids

    Dumbser, Michael; Peshkov, Ilya; Romenski, Evgeniy; Zanotti, Olindo

    2016-01-01

    Highlights: • High order schemes for a unified first order hyperbolic formulation of continuum mechanics. • The mathematical model applies simultaneously to fluid mechanics and solid mechanics. • Viscous fluids are treated in the frame of hyper-elasticity as generalized visco-plastic solids. • Formal asymptotic analysis reveals the connection with the Navier–Stokes equations. • The distortion tensor A in the model appears to be well-suited for flow visualization. - Abstract: This paper is concerned with the numerical solution of the unified first order hyperbolic formulation of continuum mechanics recently proposed by Peshkov and Romenski [110], further denoted as HPR model. In that framework, the viscous stresses are computed from the so-called distortion tensor A, which is one of the primary state variables in the proposed first order system. A very important key feature of the HPR model is its ability to describe at the same time the behavior of inviscid and viscous compressible Newtonian and non-Newtonian fluids with heat conduction, as well as the behavior of elastic and visco-plastic solids. Actually, the model treats viscous and inviscid fluids as generalized visco-plastic solids. This is achieved via a stiff source term that accounts for strain relaxation in the evolution equations of A. Also heat conduction is included via a first order hyperbolic system for the thermal impulse, from which the heat flux is computed. The governing PDE system is hyperbolic and fully consistent with the first and the second principle of thermodynamics. It is also fundamentally different from first order Maxwell–Cattaneo-type relaxation models based on extended irreversible thermodynamics. The HPR model represents therefore a novel and unified description of continuum mechanics, which applies at the same time to fluid mechanics and solid mechanics. In this paper, the direct connection between the HPR model and the classical hyperbolic–parabolic Navier

  10. High order ADER schemes for a unified first order hyperbolic formulation of continuum mechanics: Viscous heat-conducting fluids and elastic solids

    Dumbser, Michael, E-mail: michael.dumbser@unitn.it [Department of Civil, Environmental and Mechanical Engineering, University of Trento, Via Mesiano 77, 38123 Trento (Italy); Peshkov, Ilya, E-mail: peshkov@math.nsc.ru [Open and Experimental Center for Heavy Oil, Université de Pau et des Pays de l' Adour, Avenue de l' Université, 64012 Pau (France); Romenski, Evgeniy, E-mail: evrom@math.nsc.ru [Sobolev Institute of Mathematics, 4 Acad. Koptyug Avenue, 630090 Novosibirsk (Russian Federation); Novosibirsk State University, 2 Pirogova Str., 630090 Novosibirsk (Russian Federation); Zanotti, Olindo, E-mail: olindo.zanotti@unitn.it [Department of Civil, Environmental and Mechanical Engineering, University of Trento, Via Mesiano 77, 38123 Trento (Italy)

    2016-06-01

    Highlights: • High order schemes for a unified first order hyperbolic formulation of continuum mechanics. • The mathematical model applies simultaneously to fluid mechanics and solid mechanics. • Viscous fluids are treated in the frame of hyper-elasticity as generalized visco-plastic solids. • Formal asymptotic analysis reveals the connection with the Navier–Stokes equations. • The distortion tensor A in the model appears to be well-suited for flow visualization. - Abstract: This paper is concerned with the numerical solution of the unified first order hyperbolic formulation of continuum mechanics recently proposed by Peshkov and Romenski [110], further denoted as HPR model. In that framework, the viscous stresses are computed from the so-called distortion tensor A, which is one of the primary state variables in the proposed first order system. A very important key feature of the HPR model is its ability to describe at the same time the behavior of inviscid and viscous compressible Newtonian and non-Newtonian fluids with heat conduction, as well as the behavior of elastic and visco-plastic solids. Actually, the model treats viscous and inviscid fluids as generalized visco-plastic solids. This is achieved via a stiff source term that accounts for strain relaxation in the evolution equations of A. Also heat conduction is included via a first order hyperbolic system for the thermal impulse, from which the heat flux is computed. The governing PDE system is hyperbolic and fully consistent with the first and the second principle of thermodynamics. It is also fundamentally different from first order Maxwell–Cattaneo-type relaxation models based on extended irreversible thermodynamics. The HPR model represents therefore a novel and unified description of continuum mechanics, which applies at the same time to fluid mechanics and solid mechanics. In this paper, the direct connection between the HPR model and the classical hyperbolic–parabolic Navier

  11. A performance analysis of integrated solid oxide fuel cell and heat recovery steam generator for IGFC system

    Rudra, Souman; Lee, Jinwook; Rosendahl, Lasse

    2010-01-01

    efficiencies can be achieved. The outputs from SOFC can be utilized by heat recovery steam generator (HRSG), which drives the steam turbine for electricity production. The SOFC stack model was developed using the process flow sheet simulator Aspen Plus, which is of the equilibrium type. Various ranges...... of syngas properties gathered from different literature were used for the simulation. The results indicate a trade-off efficiency and power with respect to a variety of SOFC inputs. The HRSG located after SOFC was included in the current simulation study with various operating parameters. This paper...... describes IGFC power plants, particularly the optimization of HRSG to improve the efficiency of the heat recovery from the SOFC exhaust gas and to maximize the power production in the steam cycle in the IGFC system. HRSG output from different pressure levels varies depending on the SOFC output. The steam...

  12. Removal of Persistent Organic Pollutants from a Solid Matrix by Thermal Desorption Technology Using Conventional and Microwave Heating

    Mašín, P.; Hendrych, J.; Kroužek, J.; Kubal, M.; Kochánková, L.; Sobek, Jiří

    2013-01-01

    Roč. 22, č. 7A (2013), s. 2017-2021 ISSN 1018-4619. [International Conference on Environmental Management , Engineering, Planning and Economics (CEMEPE 2011) & SECOTOX Conference /3./. Skiathos Island, 19.06.2011-24.06.2011] Grant - others:GA MŽP(CZ) SP/2f3/133/08 Institutional support: RVO:67985858 Keywords : thermal desorption * microwave heating * remediation * persistent pollutants * pilot scale Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 0.527, year: 2013

  13. Thermophysical properties of 22 pure metals in the solid and liquid state - The pulse-heating data collection

    Hüpf, T.; Cagran, C.; Pottlacher, G.

    2011-05-01

    The workgroup of subsecond thermophysics in Graz has a long tradition in performing fast pulseheating experiments on metals and alloys. Thereby, wire-shaped specimens are rapidly heated (108 K/s) by a large current-pulse (104 A). This method provides thermophysical properties like volume-expansion, enthalpy and electrical resistivity up to the end of the liquid phase. Today, no more experiments on pure metals are to be expected, because almost all elements, which are suitable for pulse-heating so far, have been investigated. The requirements for pulse-heating are: a melting point which is high enough to enable pyrometric temperature measurements and the availability of wire-shaped specimens. These elements are: Co, Cu, Au, Hf, In, Ir, Fe, Pb, Mo, Ni, Nb, Pd, Pt, Re, Rh, Ag, Ta, Ti, W, V, Zn, and Zr. Hence, it is the correct time to present the results in a collected form. We provide data for the above mentioned quantities together with basic information on each material. The uniqueness of this compilation is the high temperature range covered and the homogeneity of the measurement conditions (the same method, the same laboratory, etc.). The latter makes it a good starting point for comparative analyses (e.g. a comparison of all 22 enthalpy traces is in first approximation conform with the rule of Dulong-Petit which states heat capacity - the slope of enthalpy traces - as a function of the number of atoms). The data is useful for input parameters in numerical simulations and it is a major purpose of our ongoing research to provide data for simulations of casting processes for the metal working industry. This work demonstrates some examples of how a data compilation like this can be utilized. Additionally, the latest completive measurement results on Ag, Ni, Ti, and Zr are described.

  14. Thermophysical properties of 22 pure metals in the solid and liquid state – The pulse-heating data collection

    Pottlacher G.

    2011-05-01

    Full Text Available The workgroup of subsecond thermophysics in Graz has a long tradition in performing fast pulseheating experiments on metals and alloys. Thereby, wire-shaped specimens are rapidly heated (108 K/s by a large current-pulse (104 A. This method provides thermophysical properties like volume-expansion, enthalpy and electrical resistivity up to the end of the liquid phase. Today, no more experiments on pure metals are to be expected, because almost all elements, which are suitable for pulse-heating so far, have been investigated. The requirements for pulse-heating are: a melting point which is high enough to enable pyrometric temperature measurements and the availability of wire-shaped specimens. These elements are: Co, Cu, Au, Hf, In, Ir, Fe, Pb, Mo, Ni, Nb, Pd, Pt, Re, Rh, Ag, Ta, Ti, W, V, Zn, and Zr. Hence, it is the correct time to present the results in a collected form. We provide data for the above mentioned quantities together with basic information on each material. The uniqueness of this compilation is the high temperature range covered and the homogeneity of the measurement conditions (the same method, the same laboratory, etc.. The latter makes it a good starting point for comparative analyses (e.g. a comparison of all 22 enthalpy traces is in first approximation conform with the rule of Dulong-Petit which states heat capacity – the slope of enthalpy traces – as a function of the number of atoms. The data is useful for input parameters in numerical simulations and it is a major purpose of our ongoing research to provide data for simulations of casting processes for the metal working industry. This work demonstrates some examples of how a data compilation like this can be utilized. Additionally, the latest completive measurement results on Ag, Ni, Ti, and Zr are described.

  15. The influence of gas–solid reaction kinetics in models of thermochemical heat storage under monotonic and cyclic loading

    Nagel, T.; Shao, H.; Roßkopf, C.; Linder, M.; Wörner, A.; Kolditz, O.

    2014-01-01

    Highlights: • Detailed analysis of cyclic and monotonic loading of thermochemical heat stores. • Fully coupled reactive heat and mass transport. • Reaction kinetics can be simplified in systems limited by heat transport. • Operating lines valid during monotonic and cyclic loading. • Local integral degree of conversion to capture heterogeneous material usage. - Abstract: Thermochemical reactions can be employed in heat storage devices. The choice of suitable reactive material pairs involves a thorough kinetic characterisation by, e.g., extensive thermogravimetric measurements. Before testing a material on a reactor level, simulations with models based on the Theory of Porous Media can be used to establish its suitability. The extent to which the accuracy of the kinetic model influences the results of such simulations is unknown yet fundamental to the validity of simulations based on chemical models of differing complexity. In this article we therefore compared simulation results on the reactor level based on an advanced kinetic characterisation of a calcium oxide/hydroxide system to those obtained by a simplified kinetic model. Since energy storage is often used for short term load buffering, the internal reactor behaviour is analysed under cyclic partial loading and unloading in addition to full monotonic charge/discharge operation. It was found that the predictions by both models were very similar qualitatively and quantitatively in terms of thermal power characteristics, conversion profiles, temperature output, reaction duration and pumping powers. Major differences were, however, observed for the reaction rate profiles themselves. We conclude that for systems not limited by kinetics the simplified model seems sufficient to estimate the reactor behaviour. The degree of material usage within the reactor was further shown to strongly vary under cyclic loading conditions and should be considered when designing systems for certain operating regimes

  16. In situ characterization of thermal conductivities of irradiated solids by using ion beam heating and infrared imaging

    Mondrik, Nicholas; Gigax, Jonathan; Wang, Xuemei; Price, Lloyd [Department of Nuclear Engineering, Texas A and M University, College Station, TX 77843 (United States); Wei, Chaochen [Materials Science and Engineering Department, Texas A and M University, College Station, TX 77843 (United States); Shao, Lin, E-mail: lshao@tamu.edu [Department of Nuclear Engineering, Texas A and M University, College Station, TX 77843 (United States); Materials Science and Engineering Department, Texas A and M University, College Station, TX 77843 (United States)

    2014-08-01

    We propose a method to characterize thermal properties of ion irradiated materials. This method uses an ion beam as a heating source to create a hot spot on sample surface. Infrared imaging is used as a surface temperature mapping tool to record hot zone spreading. Since ion energy, ion flux, and ion penetration depth can be precisely controlled, the beam heating data is highly reliable and repeatable. Using a high speed infrared camera to capture lateral spreading of the hot zone, thermal diffusivity can be readily extracted. The proposed method has advantages in studying radiation induced thermal property changes, for which radiation damage can be introduced by using an irradiating beam over a relatively large beam spot and beam heating can be introduced by using a focused testing beam over a relatively small beam spot. These two beams can be switched without breaking vacuum. Thus thermal conductivity changes can be characterized in situ with ion irradiation. The feasibility of the technique is demonstrated on a single crystal quartz substrate.

  17. In situ characterization of thermal conductivities of irradiated solids by using ion beam heating and infrared imaging

    Mondrik, Nicholas; Gigax, Jonathan; Wang, Xuemei; Price, Lloyd; Wei, Chaochen; Shao, Lin

    2014-01-01

    We propose a method to characterize thermal properties of ion irradiated materials. This method uses an ion beam as a heating source to create a hot spot on sample surface. Infrared imaging is used as a surface temperature mapping tool to record hot zone spreading. Since ion energy, ion flux, and ion penetration depth can be precisely controlled, the beam heating data is highly reliable and repeatable. Using a high speed infrared camera to capture lateral spreading of the hot zone, thermal diffusivity can be readily extracted. The proposed method has advantages in studying radiation induced thermal property changes, for which radiation damage can be introduced by using an irradiating beam over a relatively large beam spot and beam heating can be introduced by using a focused testing beam over a relatively small beam spot. These two beams can be switched without breaking vacuum. Thus thermal conductivity changes can be characterized in situ with ion irradiation. The feasibility of the technique is demonstrated on a single crystal quartz substrate

  18. Fragmentation of quarks and gluons

    Soeding, P.

    1983-10-01

    The author presents a review about quark and gluon jets. He describes the particle contents of the different types of jets. Finally he considers the hadronization mechanism with special regards to three-jet events in e + e - annihilation and hadronization in nuclear matter. (HSI)

  19. Quarks, history of a discovery

    Husson, D.

    2000-01-01

    This book gives a presentation of quarks and stresses on the historical aspects of the studies that led to their discovery. The 'aesthetical' motivations of the scientists in their research are explained with only a minimum of mathematical concepts. (J.S.)

  20. Phase space quark counting rule

    Wei-gin, C.; Lo, S.

    1980-01-01

    A simple quark counting rule based on phase space consideration suggested before is used to fit all 39 recent experimental data points on inclusive reactions. Parameter free relations are found to agree with experiments. Excellent detail fits are obtained for 11 inclusive reactions

  1. Correlations among static quark masses

    Lewin, K.; Motz, G.B.

    1987-01-01

    Nonrelativistic heavy quarkonia potentials with Coulomb and linearly rising limiting behaviour are correlated additively by Taylor expansion extracting the limiting structure and a constant term. Relations between fit parameters of different potentials including the quark masses m b and m c , are obtained. The known stability of the difference m b -m c , appears as direct consequence of flavour invariance of the potentials

  2. Quark-gluon plasma 2

    1995-01-01

    This is a sequel to the review volume Quark-Gluon Plasma. There are 13 articles contributed by leading investigators in the field, covering a wide range of topics about the theoretical approach to the subject. These contributions are timely reviews of nearly all the actively pursued problems, written in a pedagogical style suitable for beginners as well as experienced researchers.

  3. Quark Matter '87: Concluding remarks

    Gyulassy, M.

    1988-03-01

    This year marked the beginning of the experimental program at BNL and CERN to probe the properties of ultra dense hadronic matter and to search for the quark-gluon plasma phase of matter. Possible implications of the preliminary findings are discussed. Problems needing further theoretical and experimental study are pointed out. 50 refs

  4. Observation of the Top Quark

    Kim, S. B.

    1995-08-01

    Top quark production is observed in{bar p}p collisions at{radical}s= 1.8 TeV at the Fermilab Tevatron. The Collider Detector at Fermilab (CDF) and D{O} observe signals consistent with t{bar t} to WWb{bar b}, but inconsistent with the background prediction by 4.8{sigma} (CDF), 4.6a (D{O}). Additional evidence for the top quark Is provided by a peak in the reconstructed mass distribution. The kinematic properties of the excess events are consistent with the top quark decay. They measure the top quark mass to be 176{plus_minus}8(stat.){plus_minus}10(sys.) GeV/c{sup 2} (CDF), 199{sub -21}{sup+19}(stat.){plus_minus}22(sys.) GeV/c{sup 2} (D{O}), and the t{bar t} production cross section to be 6.8{sub -2.4}{sup+3.6}pb (CDF), 6.4{plus_minus}2.2 pb (D{O}).

  5. Hydrodynamics of a quark droplet

    Bjerrum-Bohr, Johan J.; Mishustin, Igor N.; Døssing, Thomas

    2012-01-01

    We present a simple model of a multi-quark droplet evolution based on the hydrodynamical description. This model includes collective expansion of the droplet, effects of the vacuum pressure and surface tension. The hadron emission from the droplet is described following Weisskopf's statistical...

  6. Physics of the Quark Model

    Young, Robert D.

    1973-01-01

    Discusses the charge independence, wavefunctions, magnetic moments, and high-energy scattering of hadrons on the basis of group theory and nonrelativistic quark model with mass spectrum calculated by first-order perturbation theory. The presentation is explainable to advanced undergraduate students. (CC)

  7. NA60 frees the quarks

    2003-01-01

    Fitted with new state-of-the-art silicon detectors, NA60 is prepared to study the phase transition from confined hadronic matter to a deconfined (free) quark-gluon plasma, a state of matter which probably existed an instant after the Big Bang.

  8. Quark-Gluon Plasma Signatures

    Vogt, Ramona

    1998-01-01

    Aspects of quark-gluon plasma signatures that can be measured by CMS are discussed. First the initial conditions of the system from minijet production are introduced, including shadowing effects. Color screening of the Upsilon family is then presented, followed by energy loss effects on charm and bottom hadrons, high Pt jets and global observables.

  9. Pions to Quarks

    Brown, Laurie Mark; Dresden, Max; Hoddeson, Lillian

    2009-01-01

    Part I. Introduction; 1. Pions to quarks: particle physics in the 1950s Laurie M Brown, Max Dresden and Lillian Hoddeson; 2. Particle physics in the early 1950s Chen Ning Yang; 3. An historian's interest in particle physics J. L. Heilbron; Part II. Particle discoveries in cosmic rays; 4. Cosmic-ray cloud-chamber contributions to the discovery of the strange particles in the decade 1947-1957 George D. Rochester; 5. Cosmic-ray work with emulsions in the 1940s and 1950s Donald H. Perkins; Part III. High-energy nuclear physics; Learning about nucleon resonances with pion photoproduction Robert L. Walker; 7. A personal view of nucleon structure as revealed by electron scattering Robert Hofstadter; 8. Comments on electromagnetic form factors of the nucleon Robert G. Sachs and Kameshwar C. Wali; Part IV. The new laboratory; 9. The making of an accelerator physicist Matthew Sands; 10. Accelerator design and construction in the 1950s John P. Blewett; 11. Early history of the Cosmotron and AGS Ernest D. Courant; 12. Panel on accelerators and detectors in the 1950s Lawrence W. Jones, Luis W. Alvarez, Ugo Amaldi, Robert Hofstadter, Donald W. Kerst, Robert R. Wilson; 13. Accelerators and the Midwestern Universities Research Association in the 1950s Donald W. Kerst; 14. Bubbles, sparks and the postwar laboratory Peter Galison; 15. Development of the discharge (spark) chamber in Japan in the 1950s Shuji Fukui; 16. Early work at the Bevatron: a personal account Gerson Goldhaber; 17. The discovery of the antiproton Owen Chamberlain; 18. On the antiproton discovery Oreste Piccioni; Part V. The Strange Particles; 19. The hydrogen bubble chamber and the strange resonances Luis W. Alvarez; 20. A particular view of particle physics in the fifties Jack Steinberger; 21. Strange particles William Chinowsky; 22. Strange particles: production by Cosmotron beams as observed in diffusion cloud chambers William B. Fowler; 23. From the 1940s into the 1950s Abraham Pais; Part VI. Detection of the

  10. Top quark physics at the LHC

    Jeong Kim Tae

    2014-04-01

    Full Text Available In 2011, an integrated luminosity of more than 5 fb−1 at 7 TeV has been delivered by the LHC. The measurement of the cross section in top quark pair production and in single top quark production, top quark mass, top quark properties and new physics searches in top quark decays have been performed at the CMS experiment with various integrated luminosities. An overview of the latest results of these measurements and searches by the time of ICFP 2012 conference will be presented.

  11. Simulation of volumetrically heated pebble beds in solid breeding blankets for fusion reactors. Modelling, experimental validation and sensitivity studies

    Hernandez Gonzalez, Francisco Alberto

    2016-01-01

    The Breeder Units contains pebble beds of lithium orthosilicate (Li_4SiO_4) as tritium breeder material and beryllium as neutron multiplier. In this dissertation a closed validation strategy for the thermo-mechanical validation of the Breeder Units has been developed. This strategy is based on the development of dedicated testing and modeling tools, which are needed for the qualification of the thermo-mechanical functionality of these components in an out-of-pile experimental campaign. The neutron flux in the Breeder Units induces a nonhomogeneous volumetric heating in the pebble beds that must be mimicked in an out-of-pile experiment with an external heating system minimizing the intrusion in the pebble beds. Therefore, a heater system that simulates this volumetric heating has been developed. This heater system is based on ohmic heating and linear heater elements, which approximates the point heat sources of the granular material by linear sources. These linear sources represent ''linear pebbles'' in discrete locations close enough to relatively reproduce the thermal gradients occurring in the functional materials. The heater concept has been developed for the Li_4SiO_4 and it is based on a hexagonal matrix arrangement of linear and parallel heater elements of diameter 1 mm separated by 7 mm. A set of uniformly distributed thermocouples in the transversal and longitudinal direction in the pebble bed midplane allows a 2D temperature reconstruction of that measurement plane by means of biharmonic spline interpolation. This heating system has been implemented in a relevant Breeder Unit region and its proof-of-concept has been tested in a PRE-test Mock-Up eXperiment (PREMUX) that has been designed and constructed in the frame of this dissertation. The packing factor of the pebble bed with and without the heating system does not show significant differences, giving an indirect evidence of the low intrusion of the system. Such low intrusion has been confirmed by in

  12. Simulation of volumetrically heated pebble beds in solid breeding blankets for fusion reactors. Modelling, experimental validation and sensitivity studies

    Hernandez Gonzalez, Francisco Alberto

    2016-10-14

    The Breeder Units contains pebble beds of lithium orthosilicate (Li{sub 4}SiO{sub 4}) as tritium breeder material and beryllium as neutron multiplier. In this dissertation a closed validation strategy for the thermo-mechanical validation of the Breeder Units has been developed. This strategy is based on the development of dedicated testing and modeling tools, which are needed for the qualification of the thermo-mechanical functionality of these components in an out-of-pile experimental campaign. The neutron flux in the Breeder Units induces a nonhomogeneous volumetric heating in the pebble beds that must be mimicked in an out-of-pile experiment with an external heating system minimizing the intrusion in the pebble beds. Therefore, a heater system that simulates this volumetric heating has been developed. This heater system is based on ohmic heating and linear heater elements, which approximates the point heat sources of the granular material by linear sources. These linear sources represent ''linear pebbles'' in discrete locations close enough to relatively reproduce the thermal gradients occurring in the functional materials. The heater concept has been developed for the Li{sub 4}SiO{sub 4} and it is based on a hexagonal matrix arrangement of linear and parallel heater elements of diameter 1 mm separated by 7 mm. A set of uniformly distributed thermocouples in the transversal and longitudinal direction in the pebble bed midplane allows a 2D temperature reconstruction of that measurement plane by means of biharmonic spline interpolation. This heating system has been implemented in a relevant Breeder Unit region and its proof-of-concept has been tested in a PRE-test Mock-Up eXperiment (PREMUX) that has been designed and constructed in the frame of this dissertation. The packing factor of the pebble bed with and without the heating system does not show significant differences, giving an indirect evidence of the low intrusion of the system. Such

  13. Intensive heat method for using non-segregate fine tailings for generating hot process water and stable solids that can support traffic

    Betzer-Zilevitch, M. [Ex-Tar Technologies Inc., AB (Canada)

    2010-07-01

    This power point presentation described a method developed to extract energy from non-segregated fine tailings for generating hot process water. The method produced stable solids that were able to support traffic. Discharged non-segregated tailings passed through a zero liquid discharge direct contact steam generator (DCSG) and were then further treated and returned to the oil sands mine and bitumen extraction facility. A direct contact heat exchanger and condenser removed contaminates. Laboratory analyses confirmed that the DCSG condensate was toxic. Light organics were not destroyed. The method was then simulated in order to investigate the impact of pressure on performance. The study demonstrated that the method is both simple and robust. Non-segregated asphaltene-rich fine tailing streams can be used, and no changes to extraction, oil separation, or froth treatment equipment is needed. A cost benefit analysis was included. tabs., figs.

  14. Decentralised power generation using solid biomass - Know-how on combined heat and power generation for investors; Dezentrale Stromerzeugung mit Feststoffbiomasse

    Schmid, M.; Gaegauf, Ch.; Sattler, M.

    2007-01-15

    This comprehensive report made by the Centre of Appropriate Technology and Social Ecology in Langenbruck, Switzerland presents a summary of know-how for investors on combined heat and power generation using solid biomass in installations with an electrical rating of up to one megawatt. Topics covered include a review of the reasons for using biomass to generate electricity - with the results of an analysis of potential in Switzerland and the European Union - and of economic assessment methods for the choice of technology and manufacturers. A SWOT (strengths, weaknesses, opportunities and threats) analysis of technologies is presented and existing biomass-fired installations in Switzerland are listed. A comparison with centrally-refined combustibles is presented and examples of cost and profitability calculations are given. Finally technological background information is presented, including information on 'forgotten' technologies.

  15. The effect of dynamical quark mass on the calculation of a strange quark star's structure

    Gholam Hossein Bordbar; Babak Ziaei

    2012-01-01

    We discuss the dynamical behavior of strange quark matter components,in particular the effects of density dependent quark mass on the equation of state of strange quark matter.The dynamical masses of quarks are computed within the Nambu-Jona-Lasinio model,then we perform strange quark matter calculations employing the MIT bag model with these dynamical masses.For the sake of comparing dynamical mass interaction with QCD quark-quark interaction,we consider the one-gluon-exchange term as the effective interaction between quarks for the MIT bag model.Our dynamical approach illustrates an improvement in the obtained equation of state values.We also investigate the structure of the strange quark star using TolmanOppenheimer-Volkoff equations for all applied models.Our results show that dynamical mass interaction leads to lower values for gravitational mass.

  16. Effect of recycling activities on the heating value of solid waste: case study of the Greater Vancouver Regional District (Metro Vancouver).

    Abedini, Ali R; Atwater, James W; Fu, George Yuzhu

    2012-08-01

    Two main goals of the integrated solid waste management system (ISWMS) of Metro Vancouver (MV) include further recycling of waste and energy recovery via incineration of waste. These two very common goals, however, are not always compatible enough to fit in an ISWMS depending on waste characteristics and details of recycling programs. This study showed that recent recycling activities in MV have negatively affected the net heating value (NHV) of municipal solid waste (MSW) in this regional district. Results show that meeting MV's goal for additional recycling of MSW by 2015 will further reduce the NHV of waste, if additional recycling activities are solely focused on more extensive recycling of packaging materials (e.g. paper and plastic). It is concluded that 50% additional recycling of paper and plastic in MV will increase the overall recycling rate to 70% (as targeted by the MV for 2015) and result in more than 8% reduction in NHV of MSW. This reduction translates to up to 2.3 million Canadian dollar (CAD$) less revenue at a potential waste-to-energy (WTE) plant with 500 000 tonnes year(-1) capacity. Properly designed recycling programmes, however, can make this functional element of ISWMS compatible with green goals of energy recovery from waste. Herein an explanation of how communities can increase their recycling activities without affecting the feasibility of potential WTE projects is presented.

  17. An extended analytical model for solid-state phase transformation upon continuous heating and cooling processes: Application in γ/α transformation

    Jiang, Y.-H.; Liu, F.; Song, S.-J.

    2012-01-01

    An extended analytical model is derived for non-isothermal solid-state phase transformation assuming interface-controlled growth mode, e.g. polymorphic or allotropic transformation. In the modeling, incorporation of thermodynamic factor into kinetics of nucleation and growth is performed, so that the model can be used to describe the transformation occurring either near or far from the equilibrium state. Furthermore, the effect of the initial transformation temperature is included through a special treatment for the “temperature integral”, so that the model can be used to depict the transformation during either continuous heating or continuous cooling. Numerical calculations demonstrate that the extended analytical model is accurate enough for practical use. On this basis, a general rate equation for non-isothermal (isochronal heating and cooling) transformation is derived. Applying the present model, the overall kinetic behavior of γ/α transformation in binary substitutional Fe-based alloys (e.g. Fe–Mn and Fe–Cu) upon cooling, measured by dilatometry, is described successfully. Compared with previous work, where a site saturation assumption is generally made, the prevalence of continuous nucleation deduced using the present model prediction seems more reasonable.

  18. Simulating at realistic quark masses. Light quark masses

    Goeckeler, M. [Regensburg Univ. (Germany). Inst. fuer Physik 1 - Theoretische Physik; Horsley, R.; Zanotti, J.M. [Edinburgh Univ. (United Kingdom). School of Physics; Nakamura, Y.; Pleiter, D. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC; Rakow, P.E.L. [Liverpool Univ. (United Kingdom). Dept. of Mathematical Sciences; Schierholz, G. [Deutsches Elektronen-Synchrotron (DESY), Zeuthen (Germany). John von Neumann-Inst. fuer Computing NIC]|[Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); Streuer, T. [Kentucky Univ., Lexington, KY (United States). Dept. of Physics and Astronomy; Stueben, H. [Konrad-Zuse-Zentrum fuer Informationstechnik Berlin (ZIB) (Germany)

    2006-11-15

    We present new results for light quark masses. The calculations are performed using two flavours of O(a) improved Wilson fermions. We have reached lattice spacings as small as a {proportional_to}0.07 fm and pion masses down to m{sub {pi}} {proportional_to}340 MeV in our simulations. This gives us significantly better control on the chiral and continuum extrapolations. (orig.)

  19. Heat capacity and thermodynamics of solid and liquid pyridine-3-carboxylic acid (nicotinic acid) over the temperature range 296 K to 531 K

    Joseph, Abhinav; Bernardes, Carlos E.S.; Minas da Piedade, Manuel E.

    2012-01-01

    Highlights: ► We determined the heat capacity of solid and liquid nicotinic acid by DSC. ► We determined Δ 357.8K 305.6K H m o (NA,crII) by Calvet microcalorimetry. ► We studied the thermodynamics of the cr II → cr I phase transition. ► We determined the Δ f G m o –T diagram of nicotinic acid for T = (296 to 531) K. - Abstract: The molar heat capacity of pyridine-3-carboxylic acid (nicotinic acid) for T = (296 to 531) K was investigated by differential scanning calorimetry (DSC) and Calvet-drop microcalorimetry. The measurements extended up to the liquid range and also covered the interval where a reversible and fast solid-solid (cr II → cr I) phase transition occurs. The molar enthalpies and entropies of that phase transition and of fusion were obtained as T trs = (455.0 ± 0.2) K, Δ trs H m o = (0.90 ± 0.10) kJ ⋅ mol −1 , Δ trs S m o = (1.98 ± 0.22) J ⋅ K −1 ⋅ mol −1 , T fus = (509.91 ± 0.04) K, Δ fus H m o = (28.2 ± 0.1) kJ ⋅ mol −1 , and Δ fus S m o = (55.30 ± 0.16) J ⋅ K −1 ⋅ mol −1 . By combining these experimental results with the previously reported Δ sub H m (NA,cr II) at T = 366.5 K, the corresponding entropy in the gaseous state calculated at the B3LYP/6-31+G(d,p) level of theory, and Δ f H m o (NA),cr II) at T = 298.15 K, it was possible to estimate the standard molar Gibbs energy of formation functions necessary for the construction of the Δ f G m ∘ vs. T diagram illustrating the enantiotropic nature of this system.

  20. QCD phase transition with chiral quarks and physical quark masses.

    Bhattacharya, Tanmoy; Buchoff, Michael I; Christ, Norman H; Ding, H-T; Gupta, Rajan; Jung, Chulwoo; Karsch, F; Lin, Zhongjie; Mawhinney, R D; McGlynn, Greg; Mukherjee, Swagato; Murphy, David; Petreczky, P; Renfrew, Dwight; Schroeder, Chris; Soltz, R A; Vranas, P M; Yin, Hantao

    2014-08-22

    We report on the first lattice calculation of the QCD phase transition using chiral fermions with physical quark masses. This calculation uses 2+1 quark flavors, spatial volumes between (4 fm)(3) and (11 fm)(3) and temperatures between 139 and 196 MeV. Each temperature is calculated at a single lattice spacing corresponding to a temporal Euclidean extent of N(t) = 8. The disconnected chiral susceptibility, χ(disc) shows a pronounced peak whose position and height depend sensitively on the quark mass. We find no metastability near the peak and a peak height which does not change when a 5 fm spatial extent is increased to 10 fm. Each result is strong evidence that the QCD "phase transition" is not first order but a continuous crossover for m(π) = 135 MeV. The peak location determines a pseudocritical temperature T(c) = 155(1)(8) MeV, in agreement with earlier staggered fermion results. However, the peak height is 50% greater than that suggested by previous staggered results. Chiral SU(2)(L) × SU(2)(R) symmetry is fully restored above 164 MeV, but anomalous U(1)(A) symmetry breaking is nonzero above T(c) and vanishes as T is increased to 196 MeV.

  1. Results on top-quark physics and top-quark-like signatures by CMS

    Chabert, Eric; CMS Collaboration

    2017-07-01

    This report reviews the results obtained by the CMS Collaboration on top quark physics, focusing on the latest ones based on p-p collisions provided by the LHC at \\sqrt{s}=13{{TeV}} during Run II. It covers measurements of single-top, top quark pairs and associated productions as well as measurements of top quark properties. Finally several beyond the standard model searches involving top quark in the final states are presented, such as searches for supersymmetry in the third generation, heavy resonances decaying into a top quark pair, or dark matter produced in association to a single-top or a top quark pair.

  2. Hadron matrix elements of quark operators in the relativistic quark model, 2. Model calculation

    Arisue, H; Bando, M; Toya, M [Kyoto Univ. (Japan). Dept. of Physics; Sugimoto, H

    1979-11-01

    Phenomenological studies of the matrix elements of two- and four-quark operators are made on the basis of relativistic independent quark model for typical three cases of the potentials: rigid wall, linearly rising and Coulomb-like potentials. The values of the matrix elements of two-quark operators are relatively well reproduced in each case, but those of four-quark operators prove to be too small in the independent particle treatment. It is suggested that the short-range two-quark correlations must be taken into account in order to improve the values of the matrix elements of the four-quark operators.

  3. Effect of graphene layer thickness and mechanical compliance on interfacial heat flow and thermal conduction in solid-liquid phase change materials.

    Warzoha, Ronald J; Fleischer, Amy S

    2014-08-13

    Solid-liquid phase change materials (PCMs) are attractive candidates for thermal energy storage and electronics cooling applications but have limited applicability in state-of-the-art technologies due to their low intrinsic thermal conductivities. Recent efforts to incorporate graphene and multilayer graphene into PCMs have led to the development of thermal energy storage materials with remarkable values of bulk thermal conductivity. However, the full potential of graphene as a filler material for the thermal enhancement of PCMs remains unrealized, largely due to an incomplete understanding of the physical mechanisms that govern thermal transport within graphene-based nanocomposites. In this work, we show that the number of graphene layers (n) within an individual graphene nanoparticle has a significant effect on the bulk thermal conductivity of an organic PCM. Results indicate that the bulk thermal conductivity of PCMs can be tuned by over an order of magnitude simply by adjusting the number of graphene layers (n) from n = 3 to 44. Using scanning electron microscopy in tandem with nanoscale analytical techniques, the physical mechanisms that govern heat flow within a graphene nanocomposite PCM are found to be nearly independent of the intrinsic thermal conductivity of the graphene nanoparticle itself and are instead found to be dependent on the mechanical compliance of the graphene nanoparticles. These findings are critical for the design and development of PCMs that are capable of cooling next-generation electronics and storing heat effectively in medium-to-large-scale energy systems, including solar-thermal power plants and building heating and cooling systems.

  4. Quark interactions and colour chemistry

    Hong-Mo, C.

    1982-01-01

    The interaction between quarks, according to the current theory of quantum chromodynamics, is similar to the electromagnetic interaction between electrons and nucleons, both being governed by locally gauge-invariant field theories. It is tempting therefore to discuss the spectroscopy of hadrons, which are quark composites bound by colour forces, in the same language as the spectroscopy of atoms and molecules which are bound states of electrons and nucleons held together by e.m. forces. Because of the difference in gauge groups, however, the dynamics are very different. Nonetheless, it appears likely that metastable multiquark hadron states can exist which are analogous to atoms and molecules in QED. In these lectures, tentative steps are taken in developing the rudiments of a new colour chemistry' of these 'atoms' and 'molecules'. (author)

  5. Mesons and quarks in nuclei

    Oset, E.

    1980-01-01

    A short review of the topic of mesons in nuclei is exposed paying particular attention to the relationship between several mesonic processes. Special emphasis is put into the microscopic pictures that can ultimately relate all these processes with the elementary coupling of mesons to the nuclear hadronic components. The importance of the short range part of the nuclear interaction opens the doors to a more basic understanding in terms of the quark components of nucleons and isobars. (orig.)

  6. Cooking Up Hot Quark Soup

    Walsh, Karen McNulty

    2011-03-28

    Near-light-speed collisions of gold ions provide a recipe for in-depth explorations of matter and fundamental forces. The Relativistic Heavy Ion Collider (RHIC) has produced the most massive antimatter nucleus ever discovered?and the first containing an anti-strange quark. The presence of strange antimatter makes this antinucleus the first to be entered below the plane of the classic Periodic Table of Elements, marking a new frontier in physics.

  7. Spin interactions of light quarks

    Simonov, Yu.A.

    1989-01-01

    Spin-spin and spin-orbit interactions of light quarks is calculated exactly, i.e. without use of perturbation expansion in (mass) -1 . Vacuum gluonic fields are represented by bilocal correlators and higher order correlators are neglected. Perturbative contribution is reproduced in lowest order by a simple modification of the bilocal correlator, and the smearing of the function in the hyperfine term is discussed. 12 refs

  8. Sea Quarks in the Proton

    Reimer Paul E

    2016-01-01

    Full Text Available The proton is a composite particle in which the binding force is responsible for the majority of its mass. To understand this structure, the distributions and origins of the quark-antiquark pairs produced by the strong force must be measured. The SeaQuest collaboration is using the Drell-Yan process to elucidate antiquark distributions in the proton and to study their modification when the proton is held within a nucleus.

  9. Quarks in high energy interactions

    Landshoff, P.V.

    1978-01-01

    The great interest of the quark parton model is that is seems to provide a successful way of relating together a variety of apparently very different reactions. In these lectures the author reviews the principal applications of the model. The following reactions are discussed: 1) Deep inelastic scattering of electrons, muons and neutrinos, 2) Production of lepton pairs, J/psi and W in hadronic collisions, 3) Electron-positron annihilation, 4) Large transverse momentum hadronic processes. (Auth.)

  10. Heavy quark and sparticle phenomenology

    Barger, V.

    1985-01-01

    Data from the CERN p anti p collider provide a new avenue for the study of heavy-quark production and possibly also provide the first indication for the sparticles of supersymmetry. This discussion of the associated phenomenology begins with charm and bottom quarks, proceeds to the strategies that lead to top quark identification, and concludes with possible supersymmetry scenarios to explain the events observed by the UA1 collaboration with large missing transverse momentum. The fusion predictions of single muon and dimuon rates are in the ballpark of UA1 observations. The discovery of isolated like-sign dimuons is at present an anomaly. The p anti p collider is a good place to do B physics, and answer the question of whether B 0 - anti B 0 mixing occurs. Also, it should soon be possible to identify a few dimuon events of W → t anti b and t anti t origins. Finally, enhanced charm in jets, if established, would have to be ascribed to non-perturbative QCD effects. In conclusion, if the UA1 monojets are of supersymmetry origin, then squark and gluino masses are already tightly constrained and dijet events with large missing transverse momentum should help distinguish between the two most promising scenarios. The top signal is not being faked by sparticles. (Nogami, K.)

  11. PEP quark search proportional chambers

    Parker, S I; Harris, F; Karliner, I; Yount, D [Hawaii Univ., Honolulu (USA); Ely, R; Hamilton, R; Pun, T [California Univ., Berkeley (USA). Lawrence Berkeley Lab.; Guryn, W; Miller, D; Fries, R [Northwestern Univ., Evanston, IL (USA)

    1981-04-01

    Proportional chambers are used in the PEP Free Quark Search to identify and remove possible background sources such as particles traversing the edges of counters, to permit geometric corrections to the dE/dx and TOF information from the scintillator and Cerenkov counters, and to look for possible high cross section quarks. The present beam pipe has a thickness of 0.007 interaction lengths (lambdasub(i)) and is followed in both arms each with 45/sup 0/ <= theta <= 135/sup 0/, ..delta..phi=90/sup 0/ by 5 proportional chambers, each 0.0008 lambdasub(i) thick with 32 channels of pulse height readout, and by 3 thin scintillator planes, each 0.003 lambdasub(i) thick. Following this thin front end, each arm of the detector has 8 layers of scintillator (one with scintillating light pipes) interspersed with 4 proportional chambers and a layer of lucite Cerenkov counters. Both the calculated ion statistics and measurements using He-CH/sub 4/ gas in a test chamber indicate that the chamber efficiencies should be >98% for q=1/3. The Landau spread measured in the test was equal to that observed for normal q=1 traversals. One scintillator plane and thin chamber in each arm will have an extra set of ADC's with a wide gate bracketing the normal one so timing errors and tails of earlier pulses should not produce fake quarks.

  12. Quark cluster model and confinement

    Koike, Yuji; Yazaki, Koichi

    2000-01-01

    How confinement of quarks is implemented for multi-hadron systems in the quark cluster model is reviewed. In order to learn the nature of the confining interaction for fermions we first study 1+1 dimensional QED and QCD, in which the gauge field can be eliminated exactly and generates linear interaction of fermions. Then, we compare the two-body potential model, the flip-flop model and the Born-Oppenheimer approach in the strong coupling lattice QCD for the meson-meson system. Having shown how the long-range attraction between hadrons, van der Waals interaction, shows up in the two-body potential model, we discuss two distinct attempts beyond the two-body potential model: one is a many-body potential model, the flip-flop model, and the other is the Born-Oppenheimer approach in the strong coupling lattice QCD. We explain how the emergence of the long-range attraction is avoided in these attempts. Finally, we present the results of the application of the flip-flop model to the baryon-baryon scattering in the quark cluster model. (author)

  13. Do bound color octet states of liberated quarks exist

    Lipkin, H.J.

    1979-01-01

    In models where quarks are liberated and color can be excited, the three-quark color-octet state is shown to be unbound and unstable against breakup into free quarks and diquarks. The signature for color excitation in deep inelastic processes will not be a bound three-quark state which decays electromagnetically but a final state containing free quarks. (author)

  14. Comparative study of ageing, heat treatment and accelerated carbonation for stabilization of municipal solid waste incineration bottom ash in view of reducing regulated heavy metal/metalloid leaching.

    Santos, Rafael M; Mertens, Gilles; Salman, Muhammad; Cizer, Özlem; Van Gerven, Tom

    2013-10-15

    This study compared the performance of four different approaches for stabilization of regulated heavy metal and metalloid leaching from municipal solid waste incineration bottom ash (MSWI-BA): (i) short term (three months) heap ageing, (ii) heat treatment, (iii) accelerated moist carbonation, and (iv) accelerated pressurized slurry carbonation. Two distinct types of MSWI-BA were tested in this study: one originating from a moving-grate furnace incineration operation treating exclusively household refuse (sample B), and another originating from a fluid-bed furnace incineration operation that treats a mixture of household and light industrial wastes (sample F). The most abundant elements in the ashes were Si (20-27 wt.%) and Ca (16-19 wt.%), followed by significant quantities of Fe, Al, Na, S, K, Mg, Ti, and Cl. The main crystalline substances present in the fresh ashes were Quartz, Calcite, Apatite, Anhydrite and Gehlenite, while the amorphous fraction ranged from 56 to 73 wt.%. The leaching values of all samples were compared to the Flemish (NEN 7343) and the Walloon (DIN 38414) regulations from Belgium. Batch leaching of the fresh ashes at natural pH showed that seven elements exceeded at least one regulatory limit (Ba, Cr, Cu, Mo, Pb, Se and Zn), and that both ashes had excess basicity (pH > 12). Accelerated carbonation achieved significant reduction in ash basicity (9.3-9.9); lower than ageing (10.5-12.2) and heat treatment (11.1-12.1). For sample B, there was little distinction between the leaching results of ageing and accelerated carbonation with respect to regulatory limits; however carbonation achieved comparatively lower leaching levels. Heat treatment was especially detrimental to the leaching of Cr. For sample F, ageing was ineffective and heat treatment had marginally better results, while accelerated carbonation delivered the most effective performance, with slurry carbonation meeting all DIN limits. Slurry carbonation was deemed the most

  15. Vector Susceptibility of QCD Vacuum from an Effective Quark-Quark Interaction

    ZONG Hong-Shi; QI Shi; CHEN Wei; WU Xiao-Hua

    2003-01-01

    .A new approach for calculating vacuum susceptibilities from an effective quark-quark interaction model is derived. As a special case, the vector vacuum susceptibility is calculated. A comparison with the results of the previous approaches is given.

  16. Comment on ``Brown dwarfs, quark stars, and quark-hadron phase transition``

    Kubis, S.; Kutschera, M. [Institute of Nuclear Physics, Cracow (Poland)

    1995-12-01

    It is shown that the cosmological quark-hadron phase transition within the Lee-Wick model with a high degree of supercooling cannot be completed. No quark stars could be produced in this scenario. (author). 2 refs.

  17. Comment on ''Brown dwarfs, quark stars, and quark-hadron phase transition''

    Kubis, S.; Kutschera, M.

    1995-12-01

    It is shown that the cosmological quark-hadron phase transition within the Lee-Wick model with a high degree of supercooling cannot be completed. No quark stars could be produced in this scenario. (author). 2 refs

  18. The significance of the heavy top quark

    Simmons, Elizabeth H.

    1997-01-01

    Experiment shows that the top quark is far heavier than the other elementary fermions. This finding has stimulated research on theories of electroweak and flavor symmetry breaking that include physics beyond the standard model. Efforts to accommodate a heavy top quark within existing frameworks have revealed constraints on model-building. Other investigations have started from the premise that a large top quark mass could signal a qualitative difference between the top quark and other fermions, perhaps in the form of new interactions peculiar to the top quark. Such new dynamics may also help answer existing questions about electroweak and flavor physics. This talk explores the implications of the heavy top quark in the context of weakly-coupled (e.g., SUSY) and strongly-coupled (e.g., technicolor) theories of electroweak symmetry breaking

  19. Top quark physics in ATLAS (CORFU 2014)

    Moreno Llácer, M; The ATLAS collaboration

    2014-01-01

    The top quark is the heaviest elementary particle observed to date. Being heavier than a W boson, it is the only quark that decays weakly, i.e. into a real W boson and a b quark, before hadronization can occur. In addition, it is the only quark whose Yukawa coupling to the Higgs boson is order of unity. For these reasons the top quark plays a special role in the Standard Model of Particle Physics and in many of its extensions. An accurate knowledge of its properties (mass, couplings, production cross section, decay branching ratios, etc.) can bring key information on fundamental interactions at the electroweak breaking scale and beyond. In this talk the latest measurements of the characteristics of the top quark carried out in the ATLAS experiment at the Large Hadron Collider are presented.

  20. Quark matter in a chiral chromodielectric model

    Broniowski, W.; Kutschera, M.; Cibej, M.; Rosina, M.

    1989-03-01

    Zero and finite temperature quark matter is studied in a chiral chromodielectric model with quark, meson and chromodielectric degrees of freedom. Mean field approximation is used. Two cases are considered: two-flavor and three-flavor quark matter. It is found that at sufficiently low densities and temperatures the system is in a chirally broken phase, with quarks acquiring effective masses of the order of 100 MeV. At higher densities and temperatures a chiral phase transition occurs and the quarks become massless. A comparison to traditional nuclear physics suggests that the chirally broken phase with massive quark gas may be the ground state of matter at densities of the order of a few nuclear saturation densities. 24 refs., 5 figs. (author)

  1. Studies report: methods for the evaluation and the prevention of accidental risks (DRA 35 - report {omega} 11). Knowledge of solid fuels self-heating; Rapport d'etude: methodes pour l'evaluation et la prevention des risques accidentels (DRA 35 - rapport {omega} 11). Connaissance des phenomenes d'autoechauffement des solides combustibles

    NONE

    2005-02-15

    The aim of this document is to present a synthesis of the knowledge on risks bond to auto-heating phenomena which occur in solid fuels storage. It analyzes the role of some factors on the heating, and more specially the mass, temperature, oxygen content of the atmosphere and humidity. It presents a general methodology of risks evaluation and measures on the risks detection and prevention. (A.L.B.)

  2. The antitumour drug 7-ethyl-10-hydroxycamptothecin monohydrate and its solid-state hydrolysis mechanism on heating.

    Ali, Md Ashraf; Noguchi, Shuji; Watanabe, Miteki; Iwao, Yasunori; Itai, Shigeru

    2016-10-01

    7-Ethyl-10-hydroxycamptothecin [systematic name: (4S)-4,11-diethyl-4,9-dihydroxy-1H-pyrano[3',4':6,7]indolizino[1,2-b]quinoline-3,14(4H,12H)-dione, SN-38] is an antitumour drug which exerts activity through the inhibition of topoisomerase I. The crystal structure of SN-38 as the monohydrate, C 22 H 20 N 2 O 5 ·H 2 O, reveals that it is a monoclinic crystal, with one SN-38 molecule and one water molecule in the asymmetric unit. When the crystal is heated to 473 K, approximately 30% of SN-38 is hydrolyzed at its lactone ring, resulting in the formation of the inactive carboxylate form. The molecular arrangement around the water molecule and the lactone ring of SN-38 in the crystal structure suggests that SN-38 is hydrolyzed by the water molecule at (x, y, z) nucleophilically attacking the carbonyl C atom of the lactone ring at (x - 1, y, z - 1). Hydrogen bonding around the water molecules and the lactone ring appears to promote this hydrolysis reaction: two carbonyl O atoms, which are hydrogen bonded as hydrogen-bond acceptors to the water molecule at (x, y, z), might enhance the nucleophilicity of this water molecule, while the water molecule at (-x, y + 1/2, -z), which is hydrogen bonded as a hydrogen-bond donor to the carbonyl O atom at (x - 1, y, z - 1), might enhance the electrophilicity of the carbonyl C atom.

  3. Top Quark Production at Hadron Colliders

    Phaf, Lukas Kaj [Univ. of Amsterdam (Netherlands)

    2004-03-01

    This thesis describes both theoretical and experimental research into top quark production. The theoretical part contains a calculation of the single-top quark production cross section at hadron colliders, at Next to Leading Order (NLO) accuracy. The experimental part describes a measurement of the top quark pair production cross section in proton-antiproton collisions, at a center of mass energy of 1.96 TeV.

  4. Phenomenology of heavy leptons and heavy quarks

    Gilman, F.J.

    1978-11-01

    The review of the quark and lepton family includes properties of the tau, SU(2) x U(1) classification of the tau and its decays, heavier leptons, the spectroscopy of heavy hadrons composed of quarks, their strong and electromagnetic decays, the weak interaction properties of the c, b, and t quarks, and the decays of hadrons containing them expected within the context of the standard SU(2) x U(1) model. 76 references

  5. Heavy quarks and their experimental consequences

    Appelquist, T.

    1975-09-01

    Recent theoretical work on heavy quark dynamics is reviewed. In the context of a color gauge theory of strong interactions, the structure of heavy quark-antiquark bound states and their decay properties is discussed. The emphasis is on the dynamical differences between heavy and light quark bound states. It is suggested that the former will more directly reflect the structure of the underlying field theory

  6. QCD thermodynamics with two flavors of quarks

    Bernard, C.; Ogilvie, M.C.; DeGrand, T.A.; DeTar, C.; Gottlieb, S.; Krasnitz, A.; Sugar, R.L.; Toussaint, D.

    1992-01-01

    We present results of numerical simulations of quantum chromo-dynamics at finite temperature on the Intel iPSC/860 parallel processor. We performed calculations with two flavors of Kogut-Susskind quarks and of Wilson quarks on 6 x 12 3 lattices in order to study the crossover from the low temperature hadronic regime to the high temperature regime. We investigate the properties of the objects whose exchange gives static screening lengths by reconstructing their correlated quark-antiquark structure. (orig.)

  7. The Skyrmions and quarks in nuclei

    Rho, M.

    1984-08-01

    It is proposed that the quark-bag description and the Skyrmion description of baryons are related to each other by quantized parameters. Topology (through a chiral anomaly) plays an important role in bridging the fundamental theory of the strong interactions (QCD) to effective theories. Some consequences on the efforts to see quark degrees of freedom in nuclear matter are discussed. It is suggested that at low energies there will be no ''smoking gun'' evidences for quark presence in nuclei

  8. The proton's spin: A quark model perspective

    Close, F.E.

    1989-01-01

    Magnetic moments and g A /g V provide information on the correlations among quark spins and flavors in the proton. I compare this information with the deep inelastic polarized data from EMC which has been claimed to show that very little of the proton's spin is due to the quarks. The possibility that there is significant polarization of strange quarks within protons is discussed. 38 refs

  9. A single quark effective potential model

    Bodmann, B.E.J.; Vasconcellos, C.A.Z.

    1994-01-01

    In the present work we construct a radial spherical symmetric single quark potential model for the nucleon, consistent with asymptotic freedom and confinement. The quark mass enters as potential parameter and that way induces indirectly an isospin dependence in the interaction. As a consequence, a contribution to the negative charge square radius of the neutron arises an an effect of the quark core, which simulates an isospin symmetry breaking effect in the nucleon due to strong interaction. (author)

  10. Test of quark fragmentation in the quark-parton model framework

    Derrick, M.; Barish, S.J.; Barnes, V.E.

    1979-08-01

    The hadronic system produced in charged-current antineutrino interactions is used to study fragmentation of the d-quark. Some problems encountered in separating the current quark-fragments are discussed. The fragmentation function for the current quark is in good agreement with the expectations of the naive quark-parton model and, in particular, there is no evidence of either a Q 2 - or x/sub BJ/-dependence. 10 references

  11. Single top quark production with CMS

    Piccolo Davide

    2013-11-01

    Full Text Available Measurements of single top quark production performed using the CMS experiment [1] data collected in 2011 at centre-of-mass energies of 7 TeV and in 2012 at 8 TeV, are presented. The cross sections for the electroweak production of single top quarks in the t-channel and in association with W-bosons is measured and the results are used to place constraints on the CKM matrix element Vtb. Measurements of top quark properties in single top quark production are also presented. The results include the measurement of the charge ratio in the single top t-channel.

  12. Thermal recombination: Beyond the valence quark approximation

    Mueller, B. [Department of Physics, Duke University, Durham, NC 27708 (United States); Fries, R.J. [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States)]. E-mail: fries@physics.umn.edu; Bass, S.A. [Department of Physics, Duke University, Durham, NC 27708 (United States); RIKEN BNL Research Center, Brookhaven National Laboratory, Upton, NY 11973 (United States)

    2005-07-07

    Quark counting rules derived from recombination models agree well with data on hadron production at intermediate transverse momenta in relativistic heavy-ion collisions. They convey a simple picture of hadrons consisting only of valence quarks. We discuss the inclusion of higher Fock states that add sea quarks and gluons to the hadron structure. We show that, when recombination occurs from a thermal medium, hadron spectra remain unaffected by the inclusion of higher Fock states. However, the quark number scaling for elliptic flow is somewhat affected. We discuss the implications for our understanding of data from the Relativistic Heavy Ion Collider.

  13. Heavy quark production in quantum chromodynamics

    Brodsky, S.J.

    1986-09-01

    For very heavy quark masses, the inclusive hadronic production of hadron pairs containing heavy quarks is predicted to be governed by QCD fusion subprocesses. For intermediate mass scales other QCD mechanisms can be important including higher-twist intrinsic contributions and low relative velocity enchancements, possibly accounting for the anomalies observed in charm hadroproduction, such as the nuclear number dependence, the longitudinal momentum distributions, and beam flavor dependence. We also discuss scaling laws for exclusive processes involving heavy quarks and diffractive excitation into heavy quark systems

  14. The quark model and asymptotic freedom

    Anon.

    1986-01-01

    The authors stress that it is not their task to provide a detailed account of the quark model (this is given in many monographs and reviews). This chapter is merely a prolog to the complex contemporary problems of high-energy physics which form the main subject of the present monograph. The quark model is based on the idea that there exist hypothetical fundamental particles - quarks, which they shall denote by q-bar/sub i/ (the index i characterizes the type of quark). From these particles and their antiparticles one constructs bound states, which are identified with the known hadrons. It turns out that all the observed mesons can be constructed from a quark q/sub i/ and an antiquark q-bar/sub i/, while the baryons (antibaryons) can be constructed from three quarks (antiquarks). To make it possible to build up all the observed hadrons and their characteristics, the authors must postulate that the quarks (antiquarks) possess the following properties: 1) spin 1/2; 2) isospin. It is necessary to introduce isospin 1/2 for the construction of the nonstrange hadrons. It has been proposed to denote the quark with isospin projection tau/sub 3/ = 1/2 by the symbol u (from the English ''up'') and the quark with isospin projection tau/sub 3/ = -1/2 by the symbol d (from the English ''down'')

  15. CP Violation in Single Top Quark Production

    Geng, Weigang [Michigan State Univ., East Lansing, MI (United States)

    2012-01-01

    We present a search for CP violation in single top quark production with the DØ experiment at the Tevatron proton-antiproton collider. CP violation in the top electroweak interaction results in different single top quark production cross sections for top and antitop quarks. We perform the search in the single top quark final state using 5.4 fb-1 of data, in the s-channel, t-channel, and for both combined. At this time, we do not see an observable CP asymmetry.

  16. Quarks as quasiparticles of bound states

    Tyapkin, A.A.

    1977-01-01

    Interpretation of quarks as strongly bound subsystems of the baryon structure, being in various states with integer the quantum numbers Q and B, is considered. Three original quark states, distinguished by Q, B, and J, are unambiguously determined from the condition that the quarks have the corresponding fractional quantum numbers while the integer quantum numbers for the whole system are known. With this in view the new quantum number ''colour'' is interpreted as a quantity, specifying the appearance of the subsystems in various eigen-states. Basing on the generalized Sakata model, the self-consistency of change of the colour states in the three-quark system is explained

  17. Measurements and searches with top quarks

    Peters, Reinhild Yvonne

    2008-01-01

    In 1995 the last missing member of the known families of quarks, the top quark, was discovered by the CDF and D0 experiments at the Tevatron, a proton-antiproton collider at Fermilab near Chicago. Until today, the Tevatron is the only place where top quarks can be produced. The determination of top quark production and properties is crucial to understand the Standard Model of particle physics and beyond. The most striking property of the top quark is its mass--of the order of the mass of a gold atom and close to the electroweak scale--making the top quark not only interesting in itself but also as a window to new physics. Due to the high mass, much higher than of any other known fermion, it is expected that the top quark plays an important role in electroweak symmetry breaking, which is the most prominent candidate to explain the mass of particles. In the Standard Model, electroweak symmetry breaking is induced by one Higgs field, producing one additional physical particle, the Higgs boson. Although various searches have been performed, for example at the Large Electron Positron Collider (LEP), no evidence for the Higgs boson could yet be found in any experiment. At the Tevatron, multiple searches for the last missing particle of the Standard Model are ongoing with ever higher statistics and improved analysis techniques. The exclusion or verification of the Higgs boson can only be achieved by combining many techniques and many final states and production mechanisms. As part of this thesis, the search for Higgs bosons produced in association with a top quark pair (t(bar t)H) has been performed. This channel is especially interesting for the understanding of the coupling between Higgs and the top quark. Even though the Standard Model Higgs boson is an attractive candidate, there is no reason to believe that the electroweak symmetry breaking is induced by only one Higgs field. In many models more than one Higgs boson are expected to exist, opening even more channels

  18. The quark revolution and the ZGS - new quarks physics since the ZGS

    Lipkin, H.J.

    1994-01-01

    Overwhelming experimental evidence for quarks as real physical constituents of hadrons along with the QCD analogs of the Balmer Formula, Bohr Atom and Schroedinger Equation already existed in 1966 but was dismissed as heresy. ZGS experiments played an important role in the quark revolution. This role is briefly reviewed and subsequent progress in quark physics is described

  19. Quark Physics without Quarks: A Review of Recent Developments in S-Matrix Theory.

    Capra, Fritjof

    1979-01-01

    Reviews the developments in S-matrix theory over the past five years which have made it possible to derive results characteristic of quark models without any need to postulate the existence of physical quarks. In the new approach, the quark patterns emerge as a consequence of combining the general S-matrix principles with the concept of order.…

  20. Emission and economic performance assessment of a solid oxide fuel cell micro-combined heat and power system in a domestic building

    Elmer, Theo; Worall, Mark; Wu, Shenyi; Riffat, Saffa B.

    2015-01-01

    Combined heat and power (CHP) is a promising technological configuration for reducing energy consumption and increasing energy security in the domestic built environment. Fuel cells, on account of their: high electrical efficiency, low emissions and useful heat output have been identified as a key technological option for improving both building energy efficiency and reducing emissions in domestic CHP applications. The work presented in this paper builds upon results currently reported in the literature of fuel cells operating in domestic building applications, with an emission and economic performance assessment of a real, commercially available SOFC mCHP system operating in a real building; under a UK context. This paper aims to assess the emission and economic performance of a commercially available solid oxide fuel cell (SOFC) mCHP system, operating at The University of Nottingham's Creative Energy Homes. The performance assessment evaluates, over a one year period, the associated carbon (emission assessment) and operational costs (economic assessment) of the SOFC mCHP case compared to a ‘base case’ of grid electricity and a highly efficient gas boiler. Results from the annual assessment show that the SOFC mCHP system can generate annual emission reductions of up to 56% and cost reductions of 177% compared to the base case scenario. However support mechanisms such as; electrical export, feed in tariff and export tariff, are required in order to achieve this, the results are significantly less without. A net present value (NPV) analysis shows that the base case is still more profitable over a 15 year period, even though the SOFC mCHP system generates annual revenue; this is on account of the SOFC's high capital cost. In summary, grid interaction and incubator support is essential for significant annual emission and cost reductions compared to a grid electricity and gas boiler scenario. Currently capital cost is the greatest barrier to the economic

  1. Non-diagonal processes of singlet and ordinary quark production

    Bejlin, V.A.; Vereshkov, G.M.; Kuksa, V.I.

    1995-01-01

    Non-diagonal processes of singlet and ordinary quark production are analyzed in the model where the down singlet quark mixes with the ordinary ones. The possibility of experimental selection of h-quark effects is demonstrated

  2. A higher twist correction to heavy quark production

    Brodsky, S.J.; Gunion, J.F.; Soper, D.E.

    1987-06-01

    The leading twist prediction for heavy quark production and a model for a higher twist correction that may be important for charm production was discussed. The correction arises from the interaction of the charm quark with spectator quarks

  3. Strange quark matter in the Universe and accelerator nuclear beams

    Okonov, Eh.

    1995-01-01

    An almost symmetric mixture of u, d and s-quarks - Strange Quark Matter (SQM) is strongly argued to be the ground and absolutely stable of the matter. Astrophysical objects, supposed to be the SQM states, could be formed as the result of the Big Bang (in the early Universe) and the conversion of neutron stars into strange ones. Such objects are considered to be favourable candidates as black holes. The unique possibility to produce the SQM under terrestrial conditions (at accelerator laboratories) are violent relativistic nucleus-nucleus collisions so called 'little big bang'. The expected singulares of SQM are reviewed which could be revealed from astrophysical observations of peculiarities of large SQM objects as well as from accelerator experiments with searching smaller SQM states including the simplest one - metastable six-quark H dihyperon. The first results of the Dubna search experiments, with considerable heating of matter and formation a dense strangeness abundant fireball (mixed phase?) in central nuclear collisions, is presented. Under these favourable conditions a candidate for H dihyperon is observed and an upper limit of production cross sections of this SQM state is estimated. Some prospects and advantages of further searches for light SQM states, using the JINR new superconducting accelerator - Nuclotron with energy 5-6 GeV per nucleon, are briefly outlined. 19 refs., 7 figs

  4. Large Psub(tr) and quark-quark cross section in the dynamical model of factorizing quarks

    Kapshay, V.N.; Sidorov, A.V.; Skachkov, N.B.

    1978-01-01

    Dynamical model of factorizing quarks containing the quark mass as free model parameter was described. Model calculations were compared with the experimental data on the cross section of the inclusive πsup(o) meson production in the proton-proton interaction. It is shown that the results of the paper are in good agreement with experiments

  5. Highlights of top quark properties measurements at ATLAS

    Barranco Navarro, Laura; The ATLAS collaboration

    2017-01-01

    The top quark is the heaviest known fundamental particle. As it is the only quark that decays before it hadronizes, this gives the unique opportunity to probe the properties of bare quarks. This talk focuses on a few recent precision measurements of top quark properties in production and decay by the ATLAS Collaboration. Measurements of the top quark mass and searches for rare top quark decays are also presented.

  6. Highlights of top quark properties measurements at ATLAS

    Barranco Navarro, Laura; The ATLAS collaboration

    2017-01-01

    The top quark is the heaviest known fundamental particle. As it is the only quark that decays before it hadronizes, this gives the unique opportunity to probe the properties of bare quarks. This talk will focus on a few recent precision measurements of top quark properties in production and decay by the ATLAS Collaboration. Measurements of the top quark mass and searches for rare top quark decays are also presented.

  7. Lattice calculation of the leading strange quark-connected contribution to the muon $g-2$

    Blum, T.; Del Debbio, L.; Hudspith, R.J.; Izubuchi, T.; Jüttner, A.; Lehner, C.; Lewis, R.; Maltman, K.; Krstić Marinković, M.; Portelli, A.; Spraggs, M.

    2016-04-11

    We present results for the leading hadronic contribution to the muon anomalous magnetic moment due to strange quark-connected vacuum polarisation effects. Simulations were performed using RBC--UKQCD's $N_f=2+1$ domain wall fermion ensembles with physical light sea quark masses at two lattice spacings. We consider a large number of analysis scenarios in order to obtain solid estimates for residual systematic effects. Our final result in the continuum limit is $a_\\mu^{(2)\\,{\\rm had},\\,s}=53.1(9)\\left(^{+1}_{-3}\\right)\\times10^{-10}$.

  8. Lattice calculation of the leading strange quark-connected contribution to the muon g−2

    Blum, T. [Physics Department, University of Connecticut,Storrs, CT 06269-3046 (United States); Boyle, P.A.; Debbio, L. Del [School of Physics and Astronomy, University of Edinburgh,Peter Guthrie Tait Road, Edinburgh EH9 3JZ (United Kingdom); Hudspith, R.J. [Department of Physics and Astronomy, York University,4700 Keele Street, Toronto, Ontario, M3J 1P3 (Canada); Izubuchi, T. [Physics Department, Brookhaven National Laboratory,Upton, NY 11973 (United States); RIKEN-BNL Research Center, Brookhaven National Laboratory,Upton, NY 11973 (United States); Jüttner, A. [School of Physics and Astronomy, University of Southampton,Southampton SO17 1BJ (United Kingdom); Lehner, C. [Physics Department, Brookhaven National Laboratory,Upton, NY 11973 (United States); Lewis, R. [Department of Physics and Astronomy, York University,4700 Keele Street, Toronto, Ontario, M3J 1P3 (Canada); Maltman, K. [Department of Mathematics and Statistics, York University,4700 Keele Street, Toronto, Ontario, M3J 1P3 (Canada); CSSM, University of Adelaide,Adelaide, SA 5005 (Australia); Marinković, M. Krstić [School of Physics and Astronomy, University of Southampton,Southampton SO17 1BJ (United Kingdom); CERN, Theoretical Physics Department, CERN,Geneva (Switzerland); Portelli, A. [School of Physics and Astronomy, University of Edinburgh,Peter Guthrie Tait Road, Edinburgh EH9 3JZ (United Kingdom); School of Physics and Astronomy, University of Southampton,Southampton SO17 1BJ (United Kingdom); Spraggs, M. [School of Physics and Astronomy, University of Southampton,Southampton SO17 1BJ (United Kingdom); Collaboration: The RBC/UKQCD collaboration

    2016-04-11

    We present results for the leading hadronic contribution to the muon anomalous magnetic moment due to strange quark-connected vacuum polarisation effects. Simulations were performed using RBC-UKQCD’s N{sub f}=2+1 domain wall fermion ensembles with physical light sea quark masses at two lattice spacings. We consider a large number of analysis scenarios in order to obtain solid estimates for residual systematic effects. Our final result in the continuum limit is a{sub μ}{sup (2)} {sup had,} {sup s}=53.1(9)({sub −3}{sup +1})×10{sup −10}.

  9. Lattice calculation of the leading strange quark-connected contribution to the muon g−2

    Blum, T.; Boyle, P.A.; Debbio, L. Del; Hudspith, R.J.; Izubuchi, T.; Jüttner, A.; Lehner, C.; Lewis, R.; Maltman, K.; Marinković, M. Krstić; Portelli, A.; Spraggs, M.

    2016-01-01

    We present results for the leading hadronic contribution to the muon anomalous magnetic moment due to strange quark-connected vacuum polarisation effects. Simulations were performed using RBC-UKQCD’s N f =2+1 domain wall fermion ensembles with physical light sea quark masses at two lattice spacings. We consider a large number of analysis scenarios in order to obtain solid estimates for residual systematic effects. Our final result in the continuum limit is a μ (2) had, s =53.1(9)( −3 +1 )×10 −10 .

  10. Quarks and leptons; what next

    Veltman, M.

    1979-01-01

    The theory of strong interactions is supposedly quantum chromodynamics, an unbroken gauge theory based on the group SU(3). The theory of weak and e.m. interactions is believed to be described by the Weinberg-GIM model, based on the spontaneously broken symmetry SU(2) x U(1). There are many uncertainties around these theories. Quantum chromodynamics has met with many successes, but the most important feature, quark confinement, has not been proven. Also other things, such as PCAC, have not yet been understood. And we have no reasonable calculation of particle masses (pion, proton, etc.). Nevertheless we consider quantum chromodynamics a reasonably respectable theory, and in this talk we will take that theory for granted. The situation with respect to the SU(2) x U(1) theory is much more difficult. No vector bosons have yet been observed, and the Higgs system is more obscure than ever. Glashow's model has been turned into a renormalizable model by Weinberg through the use of the Higgs system, but up to now no radiative corrections of the appropriate type have been measured. The only thing we know is that at low energies this Glashow model reduces to a four-fermion theory involving certain currents, and this has been checked reasonably well. Also, the discovery of charm (and hopefully the discovery of a top quark) fits beautifully into the picture along the lines of the GIM mechanism. CP violation could be due to complex quark masses according to the Kobayashi-Maskawa scheme. The point of view is taken that the existence of vector bosons is not evident, and the Higgs mechanism is a possibility at best. It is the purpose of this talk to outline and clarify this view

  11. Solid-state mAbs and ADCs subjected to heat-stress stability conditions can be covalently modified with buffer and excipient molecules.

    Valliere-Douglass, John F; Lewis, Patsy; Salas-Solano, Oscar; Jiang, Shan

    2015-02-01

    We report that a unique type of chemical modification occurs on lyophilized proteins. Freeze-dried mAbs and antibody-drug conjugates (ADCs) can be covalently modified with buffer and excipient molecules on the side chains of Glu, Asp, Thr, and Ser amino acids when subjected to temperature stress. The reaction occurs primarily via condensation of common buffers and excipients such as histidine, tris, trehalose and sucrose, with Glu and Asp carboxylates in the primary sequence of proteins. The reaction was also found to proceed through condensation of carboxylate containing buffers such as citrate, with Thr and Ser hydroxyls in the primary sequence of proteins. Based on the mass of the covalent adducts observed on mAbs and ADCs, it is apparent that the reaction produces water as a product and is thus favored in a low moisture environments such as a lyophilized protein cake. Herein, we present the evidence for the covalent modification of proteins drawn from case studies of in-depth characterization of heat-stressed mAbs and ADCs in the solid state. We also demonstrate how common charge variant assays such as imaged capillary isoelectric focusing and mass spectrometry can be used to monitor this specific class of protein modification. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

  12. 4E analysis and multi objective optimization of a micro gas turbine and solid oxide fuel cell hybrid combined heat and power system

    Sanaye, Sepehr; Katebi, Arash

    2014-02-01

    Energy, exergy, economic and environmental (4E) analysis and optimization of a hybrid solid oxide fuel cell and micro gas turbine (SOFC-MGT) system for use as combined generation of heat and power (CHP) is investigated in this paper. The hybrid system is modeled and performance related results are validated using available data in literature. Then a multi-objective optimization approach based on genetic algorithm is incorporated. Eight system design parameters are selected for the optimization procedure. System exergy efficiency and total cost rate (including capital or investment cost, operational cost and penalty cost of environmental emissions) are the two objectives. The effects of fuel unit cost, capital investment and system power output on optimum design parameters are also investigated. It is observed that the most sensitive and important design parameter in the hybrid system is fuel cell current density which has a significant effect on the balance between system cost and efficiency. The selected design point from the Pareto distribution of optimization results indicates a total system exergy efficiency of 60.7%, with estimated electrical energy cost 0.057 kW-1 h-1, and payback period of about 6.3 years for the investment.

  13. Hadronic physics of q anti q light quark mesons, quark molecules and glueballs

    Lindenbaum, S.J.

    1980-10-01

    A brief introduction reviews the development of QCD and defines quark molecules and glueballs. This review is concerned primarily with u, d, and s quarks, which provide practically all of the cross section connected with hadronic interactions. The following topics form the bulk of the paper: status of quark model classification for conventional u, d, s quark meson states; status of multiquark or quark molecule state predictions and experiments; glueballs and how to find them; and the OZI rule in decay and production and how glueballs might affect it. 17 figures, 1 table

  14. Are quarks and leptons composite

    Harari, H.

    1982-01-01

    The possibility that quarks and leptons are composite was studied. A line of reasoning was pursued which followed several steps. The standard model was assumed and the need to go beyond it was demonstrated. Different classes of ideas were considered. The notion of compositeness and its general difficulties, mainly the scale problem, were studied. A connection between composite massless fermions and an unbroken chiral symmetry was assumed. A general framework based on hypercolor and a chiral symmetry was established. The general requirements for a candidate model were established. A minimal scheme was found and its successes and failures were studied. (HK)

  15. CONFERENCE: Quark Matter '95

    Anon.

    1995-01-01

    High energy heavy ion collisions have become one of the major growth areas of modern physics. Providing common ground between particle and nuclear physics, it has produced a wave of new interest and a series of major projects to provide beams of higher energies and increasing nuclear complexity. Reflecting this interest, and despite record rainstorms, over 450 enthusiastic high energy heavy ion followers met in Monterey, California, at the 11th International Conference on Ultra-relativistic Nucleus-Nucleus Collisions. Named Quark Matter '95, the meeting was characterized by its own flood of new results from experiments studying collisions of gold nuclei at the Brookhaven Alternating Gradient Synchrotron (AGS) and with silicon beams at the CERN SPS synchrotron, as well as preliminary results from the first run with lead beams at CERN late last year (December 1994, page 15). A striking aspect of the Conference was the growth in attendance and, in particular, the large number of young physicists who attended the meeting, underlining the vitality and appeal of this important field. The new preliminary data from CERN experiments NA44, NA49, NA52, WA97, and WA98, made available with remarkable speed following the initial lead beam run in November and December 1994, represent a significant step in the study of heavy ion collisions. Physicists have finally come close to conditions where it is possible to consider event-by-event analysis of these very complex final states. The importance of this emerging approach to relativistic heavy ion collisions was emphasized by Reinhard Stock (Frankfurt) and other speakers in a pre-conference workshop devoted to physics with the collider detectors at big new projects now in the pipeline - RHIC at Brookhaven and LHC at CERN. The study of collisions of heavy nuclei at relativistic energies is dominated by the search for the Quark-Gluon Plasma, the 'soup' of free quarks and gluons expected to have played an important role

  16. Diffractive dissociation and new quarks

    White, A.R.

    1983-04-01

    We argue that the chiral limit of QCD can be identified with the strong (diffractive dissociation) coupling limit of reggeon field theory. Critical Pomeron scaling at high energy must then be directly related to an infra-red fixed-point of massless QCD and so requires a large number of flavors. This gives a direct argument that the emergence of diffraction-peak scaling, KNO scaling etc. at anti p-p colliders are evidence of a substantial quark structure still to be discovered

  17. Quark mass effects in QCD

    Shirkov, D.V.

    1982-01-01

    In this paper recent studies of invariant QCD coupling anti asub(s)(Qsup(2)) in the 2-loop approximation with account of fermionic mass effects are summarized. The main results are: An explicit expression for anti asub(s)(Qsup(2)) in the 2-loop approximation with accurate account of heavy quark masses. A quantitative analysis on the basis of the above-mentioned expression for anti asub(s)(Qsup(2)) of the energy dependence of the scale QCD parameter ν and the conclusion about its inadequacy in the modern energy range

  18. Chiral quarks and proton decay

    Chadha, S.; Daniel, M.; Gounaris, G.J.; Murphy, A.J.

    1984-04-01

    The authors calculate the hadronic matrix elements of baryon decay operators using a chiral effective Lagrangian with quarks, gluons and Goldstone boson fields. The cases where the ΔB=1 operators arise from supersymmetric SU(5) GUT as well as the minimal SU(5) GUT model are studied. In each model the results depend on two parameters. In particular there is a range of values for the two parameters, where the dominant decay modes in the minimal SU(5) GUT are: p→etae + and n→π - e + . (author)

  19. Colour isomers in quark material

    Hoegaasen, H.

    1981-01-01

    Quantum chromodynamics is stated to be analogous to quantum electrodynamics and colour to electric charge. However since there are eight gluon fields and only one photon field, and gluons have colour while photons are electrically neutral, QCD is much more complicated than QED. The concept of colour confine confinement is introduced and the addition rules for colour multiplets are discussed. It is shown that quark colour leads to isomeric meson states. Bubble chamber films from CERN groups have been examined and hyperons and (sup a)Y* resonance particles have been found, which appears to confirm the theory. (JIW)

  20. Constituent quarks as clusters in quark-gluon-parton model. [Total cross sections, probability distributions

    Kanki, T [Osaka Univ., Toyonaka (Japan). Coll. of General Education

    1976-12-01

    We present a quark-gluon-parton model in which quark-partons and gluons make clusters corresponding to two or three constituent quarks (or anti-quarks) in the meson or in the baryon, respectively. We explicitly construct the constituent quark state (cluster), by employing the Kuti-Weisskopf theory and by requiring the scaling. The quark additivity of the hadronic total cross sections and the quark counting rules on the threshold powers of various distributions are satisfied. For small x (Feynman fraction), it is shown that the constituent quarks and quark-partons have quite different probability distributions. We apply our model to hadron-hadron inclusive reactions, and clarify that the fragmentation and the diffractive processes relate to the constituent quark distributions, while the processes in or near the central region are controlled by the quark-partons. Our model gives the reasonable interpretation for the experimental data and much improves the usual ''constituent interchange model'' result near and in the central region (x asymptotically equals x sub(T) asymptotically equals 0).