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Sample records for heat of fusion

  1. Improved Heat-of-Fusion Energy Storage

    NASA Technical Reports Server (NTRS)

    Chen, K. H.; Manvi, R.

    1982-01-01

    Alkali metal/alkali-halide mixtures proposed for preventing solid buildup during energy recovery. When mixture melts (by absorption of heat of fusion), it forms two immiscible liquids. Salt-rich phase is heavier and has higher melting/recrysallization temperature; so during energy recovery salt crystallizes in this phase first. Since heat exchanger for energy recovery is in lighter metal-rich phase, solids do not form and there is no reduction of heat-recovery efficiency.

  2. Modular control of fusion power heating applications

    SciTech Connect

    Demers, D. R.

    2012-08-24

    This work is motivated by the growing demand for auxiliary heating on small and large machines worldwide. Numerous present and planned RF experiments (EBW, Lower Hybrid, ICRF, and ECH) are increasingly complex systems. The operational challenges are indicative of a need for components of real-time control that can be implemented with a moderate amount of effort in a time- and cost-effective fashion. Such a system will improve experimental efficiency, enhance experimental quality, and expedite technological advancements. The modular architecture of this control-suite serves multiple purposes. It facilitates construction on various scales from single to multiple controller systems. It enables expandability of control from basic to complex via the addition of modules with varying functionalities. It simplifies the control implementation process by reducing layers of software and electronic development. While conceived with fusion applications in mind, this suite has the potential to serve a broad range of scientific and industrial applications. During the Phase-I research effort we established the overall feasibility of this modular control-suite concept. We developed the fundamental modules needed to implement open-loop active-control and demonstrated their use on a microwave power deposition experiment.

  3. Fusion heating technology

    SciTech Connect

    Cole, A.J.

    1982-06-01

    John Lawson established the criterion that in order to produce more energy from fusion than is necessary to heat the plasma and replenish the radiation losses, a minimum value for both the product of plasma density and confinement time t, and the temperature must be achieved. There are two types of plasma heating: neutral beam and electromagnetic wave heating. A neutral beam system is shown. Main development work on negative ion beamlines has focused on the difficult problem of the production of high current sources. The development of a 30 keV-1 ampere multisecond source module is close to being accomplished. In electromagnetic heating, the launcher, which provides the means of coupling the power to the plasma, is most important. The status of heating development is reviewed. Electron cyclotron resonance heating (ECRH), lower hybrid heating (HHH), and ion cyclotron resonance heating (ICRH) are reviewed.

  4. Modeling of Heat and Mass Transfer in Fusion Welding

    SciTech Connect

    Zhang, Wei

    2011-01-01

    In fusion welding, parts are joined together by melting and subsequent solidification. Although this principle is simple, complex transport phenomena take place during fusion welding, and they determine the final weld quality and performance. The heat and mass transfer in the weld pool directly affect the size and shape of the pool, the solidification microstructure, the formation of weld defects such as porosity and humping, and the temperature distribution in the fusion zone and heat-affected zone (HAZ). Furthermore, the temperature evolution affects the kinetics and extent of various solid-state phase transformations, which in turn determine the final weld microstructure and mechanical properties. The formation of residual stresses and distortion originates from the thermal expansion and contraction during welding heating and cooling, respectively.

  5. Supplemental heating of conventional Inertial Confinement Fusion

    NASA Astrophysics Data System (ADS)

    Thomas, B. R.; Hughes, S. J.; Garbett, W. J.; Sircombe, N. J.

    2016-03-01

    We report a new ICF scheme whereby a capsule is imploded to near ignition conditions and subsequently flooded with hot electrons generated from a short-pulse laser- plasma interaction so as to heat the whole assembly by a few hundred eV. The cold dense shell pressure is increased by a larger factor than that of the hot spot at the capsule core, so that further heating and compression of the hot spot occurs. We suggest it may be possible to drive the capsule to ignition by the pressure augmentation supplied by this extra deposition of energy.

  6. Immiscible fluid: Heat of fusion heat storage system

    NASA Technical Reports Server (NTRS)

    Edie, D. D.; Melsheimer, S. S.; Mullins, J. C.

    1980-01-01

    Both heat and mass transfer in direct contact aqueous crystallizing systems were studied as part of a program desig- ned to evaluate the feasibility of direct contact heat transfer in phase change storage using aqueous salt system. Major research areas, discussed include (1) crystal growth velocity study on selected salts; (2) selection of salt solutions; (3) selection of immiscible fluids; (4) studies of heat transfer and system geometry; and (5) system demonstration.

  7. Radio frequency heating of ceramic windows in fusion applications

    SciTech Connect

    Fowler, J.D. Jr.

    1981-11-01

    Ceramic windows will be used as material barriers for radio frequency plasma heating in fusion reactors. This report examines the theory behind rf heating phenomena. Heating calculations are presented for various window materials, thicknesses, wavelengths, and power densities. The most pertinent material properties are loss tangent, thermal conductivity, dielectric constant, strength, and radiation resistance. Calculations indicate that among candidate materials, beryllium oxide offers the most promise because of its large thermal conductivity and relatively low loss tangent and dielectric constant. On the other hand, beryllia is susceptible to neutron damage, and this may adversely affect its electrical properties. Another promising candidate is sapphire, particularly at lower temperatures where the thermal conductivity is high. Fused silica suffers from low thermal conductivity and large positive temperature coefficient for loss tangent, but it may be useful under some conditions. In summary, calculations of heating can lead to elimination of some candidate materials and selection of others for further study.

  8. Fusion Plasma Theory: Task 3, Auxiliary radiofrequency heating of tokamaks

    SciTech Connect

    Scharer, J.E.

    1992-01-01

    The research performed under this grant during the past year has been concentrated on the following several key tokamak ICRF (Ion Cyclotron Range of Frequencies) coupling, heating and current drive issues: Efficient coupling during the L- to H- mode transition by analysis and computer simulation of ICRF antennas; analysis of ICRF cavity-backed coil antenna coupling to plasma edge profiles including fast and ion Bernstein wave coupling for heating and current drive; benchmarking the codes to compare with current JET, D-IIID and ASDEX experimental results and predictions for advanced tokamaks such as BPX and SSAT (Steady-State Advanced Tokamak); ICRF full-wave field solutions, power conservation, heating analyses and minority ion current drive; and the effects of fusion alpha particle or ion tail populations on the ICRF absorption. Research progress, publications, and conference and workshop presentations are summarized in this report.

  9. Review of controlled fusion research using laser heating.

    NASA Technical Reports Server (NTRS)

    Hertzberg, A.

    1973-01-01

    Development of methods for generating high laser pulse energy has stimulated research leading to new ideas for practical controlled thermonuclear fusion machines. A review is presented of some important efforts in progress, and two different approaches have been selected as examples for discussion. One involves the concept of very short pulse lasers with power output tailored, in time, to obtain a nearly isentropic compression of a deuterium-tritium pellet to very high densities and temperatures. A second approach utilizing long wavelength, long pulse, efficient gas lasers to heat a column of plasma contained in a solenoidal field is also discussed. The working requirements of the laser and various magnetic field geometries of this approach are described.

  10. Feasibility study of fusion plasma heating by relativistic high-current electron beams

    NASA Astrophysics Data System (ADS)

    Yakimenko, V.

    2017-03-01

    The goal of this research will be to study the feasibility of fusion plasma heating using ultra-short high intensity electron beam by dissipating the energy of excited wakes either in linear or nonlinear regimes.

  11. Technological issues of ion cyclotron heating of fusion plasmas

    SciTech Connect

    Hwang, D.Q.; Fortgang, C.M.

    1985-07-01

    With the recent promising results of plasma heating using electromagnetic waves (EM waves) in the ion cyclotron range of frequency (ICRF) on the Princeton Large Torus (PLT) tokamak the feasibility of employing ICRF heating to a reactor-like magnetic confinement device is increasing. The high power ICRF experiments funded on JET (Joint European Torus in England) and JT-60 (in Japan) will have rf source power in the range of 10-30 MW. The time scale for the duration of the RF pulse will range from seconds up to steady-state. The development of new RF components that can transmit and launch such high power, long pulse length, EM waves in a plasma environment is a major technological task. In general, the technology issues may be divided into two categories. The first category concerns the region where the plasma comes in contact with the wave launchers. The problems here are dominated by plasmamaterial interaction, heat deposition by the plasma onto the wave launcher, and erosion of the launcher material. It is necessary to minimize the heat deposition from the plasma, the losses of the RF wave energy in the structure, and to prevent sputtering of the antenna components. A solution involves a combined design using special materials and optimal shaping of the Faraday shield (the electrostatic shields which can be used both for an EM wave polarization adjustment and as a particle shield for the launcher). Recent studies by PPPL and McDonnell Douglas Corp. on the Faraday shield designs will be discussed. The second important area where technology development will be necessary is the transmission of high power RF waves through a gas/vacuum interface region. In the past, the vacuum feedthrough has been the bottle neck which prevented high power operation of the PLT antenna.

  12. The Measurement of the Specific Latent Heat of Fusion of Ice: Two Improved Methods.

    ERIC Educational Resources Information Center

    Mak, S. Y.; Chun, C. K. W.

    2000-01-01

    Suggests two methods for measuring the specific latent heat of ice fusion for high school physics laboratories. The first method is an ice calorimeter which is made from simple materials. The second method improves the thermal contact and allows for a more accurate measurement. Lists instructions for both methods. (Author/YDS)

  13. Heat deposition into the superconducting central column of a spherical tokamak fusion plant

    NASA Astrophysics Data System (ADS)

    Windsor, C. G.; Morgan, J. G.; Buxton, P. F.

    2015-02-01

    A key challenge in designing a fusion power plant is to manage the heat deposition into the central core containing superconducting toroidal field coils. Spherical tokamaks have limited space for shielding the central core from fast neutrons produced by fusion and the resulting gamma rays. This paper reports a series of three-dimensional computations using the Monte Carlo N-particle code to calculate the heat deposition into the superconducting core. For a given fusion power, this is considered as a function of plasma major radius R0, core radius rsc and shield thickness d. Computations over the ranges 0.6 m ⩽ R0 ⩽ 1.6 m, 0.15 m ⩽ rsc ⩽ 0.25 m and 0.15 m ⩽ d ⩽ 0.4 m are presented. The deposited power shows an exponential dependence on all three variables to within around 2%. The additional effects of source profile, the outer shield and shield material are all considered. The results can be interpolated to 2% accuracy and have been successfully incorporated into a system code. A possible pilot plant with 174 MW of fusion is shown to lead to a heat deposition into the superconducting core of order 30 kW. An estimate of 1.7 MW is made for the cryogenic plant power necessary for heat removal, and of 88 s running time for an adiabatic experiment where the heat deposition is absorbed by a 10 K temperature rise.

  14. Development of neutral beams for fusion plasma heating

    SciTech Connect

    Haselton, H.H.; Pyle, R.V.

    1980-01-01

    A state-of-the-art account of neutral beam technology at the LBL/LLNL and ORNL facilities is given with emphasis on positive-ion-based systems. The advances made in the last few years are elaborated and problem areas are identified. The ORNL program has successfully completed the neutral injection systems for PLT, ISX-B, and most recently, PDX and the ISX-B upgrade. All of these are high current (60 to 100 A), medium energy (40 to 50 keV) systems. This program is also engaged in the development of a reactor-grade advanced positive ion system (150 to 200 kV/100 A/5 to 10 s) and a multimegawatt, long pulse (30 s) heating system for ISX-C. In a joint program, LBL and LLNL are developing and testing neutral beam injection systems based on the acceleration of positive ions for application in the 80- to 160-keV range on MFTF-B, D-III, TFTR/TFM, ETF, MNS, etc. A conceptual design of a 160-keV injection system for the German ZEPHYR project is in progress at LBL/LLNL and independently at ORNL. The laboratories are also engaged in the development of negative-ion-based systems for future applications at higher energies.

  15. Estimated heats of fusion of fluoride salt mixtures suitable for thermal energy storage applications

    NASA Technical Reports Server (NTRS)

    Misra, A. K.; Whittenberger, J. D.

    1986-01-01

    The heats of fusion of several fluoride salt mixtures with melting points greater than 973 K were estimated from a coupled analysis of the available thermodynamic data and phase diagrams. Simple binary eutectic systems with and without terminal solid solutions, binary eutectics with congruent melting intermediate phases, and ternary eutectic systems were considered. Several combinations of salts were identified, most notable the eutectics LiF-22CaF2 and NaF-60MgF2 which melt at 1039 and 1273 K respectively which posses relatively high heats of fusion/gm (greater than 0.7 kJ/g). Such systems would seemingly be ideal candidates for the light weight, high energy storage media required by the thermal energy storage unit in advanced solar dynamic power systems envisioned for the future space missions.

  16. RF plasma heating in toroidal fusion devices

    SciTech Connect

    Golant, V.E.; Fedorov, V.I. )

    1989-01-01

    The purpose of the present book is to provide, in seven chapters, a unified overview of the methods for rf heating of plasmas in toroidal fusion experiments. In Chapter 1 the problem of plasma heating in tokamaks and stellarators is formulated and the requirements for auxiliary heating techniques are described. This chapter also contains a brief review of the results of research on tokamaks and stellarators. Chapter 2 is devoted to a theoretical description of the principal physical effects involved in the rf heating of plasmas, especially the characteristics of wave propagation, of the mechanisms by which waves are absorbed and plasma heating takes place, and of the nonlinear effects that accompany heating. The primary emphasis is on a qualitative physical picture of these effects. Chapters 3-6, in turn, deal with the major rf heating techniques currently under investigation, electron cyclotron (ECH), ion cyclotron (ICH), lower hybrid (LHH), and Alfven wave heating. In each of these chapters the main schemes for heating are described, the results of theoretical analyses and numerical simulations are discussed, the technology of the heating systems is briefly described, and experimental work published through the end of 1984 is reviewed. Finally, in Chapter 7 the different rf heating techniques are compared; they are contrasted with neutral beam injection, and the feasibility of adiabatic compression as a means of heating plasmas is examined. Separate abstracts were prepared for each chapter of this book. 246 refs.

  17. An Electrothermal Plasma Source Developed for Simulation of Transient Heat Loads in Future Large Fusion Devices

    NASA Astrophysics Data System (ADS)

    Gebhart, Trey; Baylor, Larry; Winfrey, Leigh

    2016-10-01

    The realization of fusion energy requires materials that can withstand high heat and particle fluxes at the plasma material interface. In this work, an electrothermal (ET) plasma source has been designed as a possible transient heat flux source for a linear plasma material interaction device. An ET plasma source operates in the ablative arc regime, which is driven by a DC capacitive discharge. The current travels through the 4mm bore of a boron nitride liner and subsequently ablates and ionizes the liner material. This results in a high density plasma with a large unidirectional bulk flow out of the source exit. The pulse length for the ET source has been optimized using a pulse forming network to have a duration of 1ms at full-width half maximum. The peak currents and maximum source energies seen in this system are 2kA and 5kJ. The goal of this work is to show that the ET source produces electron densities and heat fluxes that are comparable to transient events in future large magnetic confinement fusion devices. Heat flux, plasma temperature, and plasma density were determined for each test shot using infrared imaging and optical spectroscopy techniques. This work will compare the ET source output (heat flux, temperature, and density) with and without an applied magnetic field. Research sponsored by the Laboratory Directed Research and Development Program of Oak Ridge National Laboratory, managed by UT-Battelle, LLC, for the U. S. Department of Energy.

  18. Numerical analysis of the heat transfer and fluid flow in the butt-fusion welding process

    NASA Astrophysics Data System (ADS)

    Yoo, Jae Hyun; Choi, Sunwoong; Nam, Jaewook; Ahn, Kyung Hyun; Oh, Ju Seok

    2017-02-01

    Butt-fusion welding is an effective process for welding polymeric pipes. The process can be simplified into two stages. In heat soak stage, the pipe is heated using a hot plate contacted with one end of the pipe. In jointing stage, a pair of heated pipes is compressed against one another so that the melt regions become welded. In previous works, the jointing stage that is highly related to the welding quality was neglected. However, in this study, a finite element simulation is conducted including the jointing stage. The heat and momentum transfer are considered altogether. A new numerical scheme to describe the melt flow and pipe deformation for the butt-fusion welding process is introduced. High density polyethylene (HDPE) is used for the material. Flow via thermal expansion of the heat soak stage, and squeezing and fountain flow of the jointing stage are well reproduced. It is also observed that curling beads are formed and encounter the pipe body. The unique contribution of this study is its capability of directly observing the flow behaviors that occur during the jointing stage and relating them to welding quality.

  19. Application of amorphous filler metals in production of fusion reactor high heat flux components

    SciTech Connect

    Kalin, B.A.; Fedotov, V.T.; Grigoriev, A.E.

    1994-12-31

    The technology of Al-Si, Zr-Ti-Be and Ti-Zr-Cu-Ni amorphous filler metals for Be and graphite brazing with Cu, Mo and V was developed. The fusion reactor high heat flux components from Cu-Be, Cu-graphite, Mo-Be, Mo-graphite, V-Re and V-graphite materials were produced by brazing. Every component represents metallic base, to which Be or graphite plates are brazed. The distance between plates was equal 0.2 times the plate height. These components were irradiated by hydrogen plasma with 5 x 10{sup 6} W/m{sup 2} power. The microstructure and the element distribution in the brazed zone were investigated before and after heat plasma irradiation. Topography graphite plate surfaces and topography of metal surfaces between plates were also investigated after heat plasma irradiation. The results of microstructure investigation and material erosion are discussed.

  20. Two dimensional impinging jet cooling of high heat flux surface in magnetic confinement fusion reactor

    SciTech Connect

    Inoue, A.; Tanno, T.; Takahashi, M.

    1994-12-31

    Divertor surface of a magnetic confinement fusion reactor is exposed to strong radiation heating by high flux charged particles. According to standard design of the ITER, the heat flux of the divertor surface becomes average 15MW/m{sup 2} or more. In this study, a cooling by a two dimensional impinging jet flow is proposed to cool such high heat flux surface. For an impinging jet flow to flat heated surface, such as CHF is obtained only in the limited surface region where the jet flow hits directly. Apart from the region, the CHF decreases abruptly with the distance from the center. The main reason is that the pressure decreases abruptly as apart from the center region and the liquid flow is spread away from the heated surface region by the strong boiling. To overcome these difficulties, the authors propose that the impinging jet is applied to the heat transfer wall with a concave surface, because the pressure change becomes mild by the centrifugal force along the curved surface. The increase of the radial pressure gradient in the vertical direction to the curved surface promotes the departure of vapor bubbles near the wall region. It is expected that this mechanism as well as keeping high pressure along the flow works to enhance the CHF. To obtain the high heat flux in the wide region, a use of a two-dimensional impinging jet is suitable instead of a round jet.

  1. Development of Quasi-Optical Gyrotrons for Fusion Plasma Heating

    DTIC Science & Technology

    1988-07-11

    1987 - NRL Invention Award May 1987 - Elected to Sigma Xi 158 W Scientific Projects Managed 1) Toroidal Plasma Modeling, Department of Energy ...OFFICE SYMBOL 9 PROCUREMENT INSTRUMENT IDENTIFICATION NUMBER ORGANIZATION (If applicable) DeDartment of Energy 8c. ADDRESS (City, State, and ZIP Code) 10...Introduction The High Power Electromagnetic Radiation Branch (Code 4740) of the U. S. Naval Research Laboratory analyzes here for the Department of Energy a

  2. Energy Storage As Heat-of-Fusion in Containerized Salts.

    DTIC Science & Technology

    1980-06-27

    56 v APPENDIX A - Chemical vs. Thermal Storage for Solar Thermochem ical Power Systems...in Section V of this report. Major use of industrial scale solar power will impose requirements for massive energy storage. This report addresses the...efficiency. Once the availability of major solar thermal power becomes a reality, the energy storage problem becomes much more severe. We can expect that the

  3. Two-Dimensional Computation of Heat Transfer in Fusion Welding

    DTIC Science & Technology

    1988-09-01

    the material properties of 22 the experimental steel had to be approximated with data from the most similar alloy for which data were available (see...Transfer and Fluid Flow, p. 54, McGraw-Hill, 1980. 11. Touloukian , Y. S., Thermophysical Properties of Matter, vol. 1, pp. 925 and 1183; vol. IV, pp. 4 and...based upon the enthalpy formulation for phase change processes. Changes in thermal properties during the process have been accounted for. Temperature

  4. Development of high power radio frequency components for fusion plasma heating. Final report, Revision 3

    SciTech Connect

    1997-09-11

    The purpose of this CRADA was to develop advanced microwave heating systems for both ion cyclotron heating and electron cyclotron heating for magnetic fusion reactors. This involved low-frequency (UHF), high-power (millimeter-wave) microwave components, such as antennas, windows, and matching elements. This CRADA also involved developing conceptual designs for new microwave sources. General Atomics built and tested the distributed cooled window and provided LLNL with transmission and reflection test data in order to then benchmark the EM computer codes. The combline antenna built and analyzed by LLNL was based on a GA design. GA provided LLNL with a number of niobium plates for hot pressing and provided the necessary guidance to allow successful bonding. GA representatives were on site at LLNL on numerous occasions to consult and give guidance on the ferroelectric tuner, combline antenna and distributed window analysis.

  5. Response of materials to high heat fluxes during operation in fusion reactors

    SciTech Connect

    Hassanein, A.M.

    1988-07-01

    Very high energy deposition on first wall and other components of a fusion reactor is expected due to plasma instabilities during both normal and off-normal operating conditions. Off-normal operating conditions result from plasma disruptions where the plasma loses confinement and dumps its energy on the reactor components. High heat flux may also result from normal operating conditions due to fluctuations in plasma edge conditions. This high energy dump in a short time results in very high surface temperatures and may consequently cause melting and vaporization of these materials. The net erosion rates resulting from melting and vaporization are very important to estimate the lifetime of such components. The response of different candidate materials to this high heat fluxes is determined for different energy densities and deposition times. The analysis used a previously developed model to solve the heat conduction equation in two moving boundaries. One moving boundary is at the surface to account for surface recession due to vaporization and the second moving boundary is to account for the solid-liquid interface inside the material. The calculations are done parametrically for both the expected energy deposited and the deposition time. These ranges of energy and time are based on recent experimental observations in current fusion devices. The candidate materials analyzed are stainless steel, carbon, and tungsten. 8 refs., 9 figs.

  6. Possible generation of heat from nuclear fusion in Earth’s inner core

    NASA Astrophysics Data System (ADS)

    Fukuhara, Mikio

    2016-11-01

    The cause and source of the heat released from Earth’s interior have not yet been determined. Some research groups have proposed that the heat is supplied by radioactive decay or by a nuclear georeactor. Here we postulate that the generation of heat is the result of three-body nuclear fusion of deuterons confined in hexagonal FeDx core-centre crystals; the reaction rate is enhanced by the combined attraction effects of high-pressure (~364 GPa) and high-temperature (~5700 K) and by the physical catalysis of neutral pions: 2D + 2D + 2D → 21H + 4He + 2  + 20.85 MeV. The possible heat generation rate can be calculated as 8.12 × 1012 J/m3, based on the assumption that Earth’s primitive heat supply has already been exhausted. The H and He atoms produced and the anti-neutrino are incorporated as Fe-H based alloys in the H-rich portion of inner core, are released from Earth’s interior to the universe, and pass through Earth, respectively.

  7. Possible generation of heat from nuclear fusion in Earth’s inner core

    PubMed Central

    Fukuhara, Mikio

    2016-01-01

    The cause and source of the heat released from Earth’s interior have not yet been determined. Some research groups have proposed that the heat is supplied by radioactive decay or by a nuclear georeactor. Here we postulate that the generation of heat is the result of three-body nuclear fusion of deuterons confined in hexagonal FeDx core-centre crystals; the reaction rate is enhanced by the combined attraction effects of high-pressure (~364 GPa) and high-temperature (~5700 K) and by the physical catalysis of neutral pions: 2D + 2D + 2D → 21H + 4He + 2  + 20.85 MeV. The possible heat generation rate can be calculated as 8.12 × 1012 J/m3, based on the assumption that Earth’s primitive heat supply has already been exhausted. The H and He atoms produced and the anti-neutrino are incorporated as Fe-H based alloys in the H-rich portion of inner core, are released from Earth’s interior to the universe, and pass through Earth, respectively. PMID:27876860

  8. Possible generation of heat from nuclear fusion in Earth's inner core.

    PubMed

    Fukuhara, Mikio

    2016-11-23

    The cause and source of the heat released from Earth's interior have not yet been determined. Some research groups have proposed that the heat is supplied by radioactive decay or by a nuclear georeactor. Here we postulate that the generation of heat is the result of three-body nuclear fusion of deuterons confined in hexagonal FeDx core-centre crystals; the reaction rate is enhanced by the combined attraction effects of high-pressure (~364 GPa) and high-temperature (~5700 K) and by the physical catalysis of neutral pions: (2)D + (2)D + (2)D → 2(1)H + (4)He + 2  + 20.85 MeV. The possible heat generation rate can be calculated as 8.12 × 10(12) J/m(3), based on the assumption that Earth's primitive heat supply has already been exhausted. The H and He atoms produced and the anti-neutrino are incorporated as Fe-H based alloys in the H-rich portion of inner core, are released from Earth's interior to the universe, and pass through Earth, respectively.

  9. Heat-transfer characteristics of flowing and stationary particle-bed-type fusion-reactor blankets

    SciTech Connect

    Nietert, R.E.

    1983-02-01

    The heat-transfer characteristics of flowing and stationary packed-particle beds have recently become of interest in connection with conceptual designs of fusion reactor blankets. A detailed literature survey has shown that the processes taking place in such beds are not fully understood despite their widespread use in the chemical industry and other engineering disciplines for more than five decades. In this study, two experimental investigations were pursued. In the first, a heat-transfer loop was constructed through which glass microspheres were allowed to flow by rgravity at controlled rates through an electrically heated stainless steel tubular test section. In the second, an annular packed bed was constructed in which heat was applied through the outer wall by electric heating of a stainless steel tube. Cooling occurred at the inner wall of the annular bed by flowing air through the central tube. A second air stream was allowed to flow through the voids of the packed bed. An error-minimization technique was utilized in order to obtain the two-dimensional one-parameter effective conductivity for the bed by comparing the experimental and theoretically predicted temperature profiles. Experiments were conducted for various modified Reynolds numbers less than ten.

  10. Characteristics of GTA fusion zones and heat affected zones in superalloy 713C

    NASA Astrophysics Data System (ADS)

    Lachowicz, M. B.; Dudziński, W.

    2012-09-01

    In this paper, metallographic examinations, characterising microstructural changes in the 713C superalloy subjected to remelting by GTA method, are presented. In the fusion zone, precipitation of M23C6 or M6C carbides based on chromium and molybdenum was observed. Eutectic mixtures of ( γ- gg')-M x C y type with highly developed morphology were also perceived. It was found that, in the matrix areas with non-homogeneous chemical composition, the eutectic reaction γ-γ' can occur at the temperature close to that of the precipitation of the M x C y carbides. The presence of silicon in the carbide phases can be conducive to lowering their solidification point by creating low-melting compound NbSi. Both in the fusion zone (FZ) and in the heat-affected zone (HAZ), the secondary precipitates of the Ni3(AlTi)- γ' phase, varying in size from 50 to 100 nm, were found. The lattice mismatch factor of the γ and γ' particles was +0.48 % to +0.71 %, which is characteristic of the coherent precipitates of the Ni3Al phase enriched with titanium. No dislocations or stacking faults were observed in the microstructure of the FZ. In the HAZ, some primary undissolved γ' precipitates, with a part of aluminium probably replaced with niobium were observed, which raised their melting point.

  11. Initial confinement studies of ohmically heated plasmas in the Tokamak Fusion Test Reactor

    SciTech Connect

    Efthimion, P.C.; Bell, M.; Blanchard, W.R.; Bretz, N.; Cecchi, J.L.; Coonrod, J.; Davis, S.; Dylla, H.F.; Fonck, R.; Furth, H.P.

    1984-06-01

    Initial operation of the Tokamak Fusion Test Reactor (TFTR) has concentrated upon confinement studies of ohmically heated hydrogen and deuterium plasmas. Total energy confinement times (tau/sub E/) are 0.1 to 0.2 s for a line-average density range (anti n/sub e/) of 1 to 2.5 x 10/sup 19/ m/sup -3/ with electron temperatures of T/sub e/(o) approx. 1.2 to 2.2 keV, ion temperatures of T/sub i/(o) approx. 0.9 to 1.5 keV, and Z/sub eff/ approx. 3. A comparison of PLT, PDX, and TFTR plasma confinement supports a dimension-cubed scaling law.

  12. Conceptual design of a laser-fusion power plant. Part II. Two technical options: 1. JADE reactor; 2. Heat transfer by heat pipes

    SciTech Connect

    Not Available

    1981-07-01

    A laser fusion reactor concept is described that employs liquid metal walls. The concept envisions a porous medium, called the JADE, of specific geometry lining the reactor cavity. Some advantages and disadvantages of the concept are pointed out. The possibility of using heat pipes for passive cooling in ICF reactors is discussed. Some of the problems are outlined. (MOW)

  13. External Heat Transfer Coefficient Measurements on a Surrogate Indirect Inertial Confinement Fusion Target

    DOE PAGES

    Miles, Robin; Havstad, Mark; LeBlanc, Mary; ...

    2015-09-15

    External heat transfer coefficients were measured around a surrogate Indirect inertial confinement fusion (ICF) based on the Laser Inertial Fusion Energy (LIFE) design target to validate thermal models of the LIFE target during flight through a fusion chamber. Results indicate that heat transfer coefficients for this target 25-50 W/m2∙K are consistent with theoretically derived heat transfer coefficients and valid for use in calculation of target heating during flight through a fusion chamber.

  14. External Heat Transfer Coefficient Measurements on a Surrogate Indirect Inertial Confinement Fusion Target

    SciTech Connect

    Miles, Robin; Havstad, Mark; LeBlanc, Mary; Golosker, Ilya; Chang, Allan; Rosso, Paul

    2015-09-15

    External heat transfer coefficients were measured around a surrogate Indirect inertial confinement fusion (ICF) based on the Laser Inertial Fusion Energy (LIFE) design target to validate thermal models of the LIFE target during flight through a fusion chamber. Results indicate that heat transfer coefficients for this target 25-50 W/m2∙K are consistent with theoretically derived heat transfer coefficients and valid for use in calculation of target heating during flight through a fusion chamber.

  15. RF heating for fusion product studies

    SciTech Connect

    Hellsten, T. Johnson, T.; Sharapov, S. E.; Kiptily, V.; Rimini, F.; Eriksson, J.; Mantsinen, M.; Schneider, M.; Tsalas, M.

    2015-12-10

    Third harmonic cyclotron heating is an effective tool for accelerating deuterium (D) beams to the MeV energy range, suitable for studying ITER relevant fast particle physics in plasmas without significant tritium content. Such experiments were recently conducted in JET with an ITER like wall in D plasmas with {sup 3}He concentrations up to 30% in order to boost the fusion reactivity by D-{sup 3}He reactions. The harmonic cyclotron heating produces high-energy tails in the MeV range of D ions by on-axis heating and of {sup 3}He ions by tangential off-axis heating. The discharges are characterized by long sawtooth free periods and a rich spectrum of MHD modes excited by the fast D and {sup 3}He ions. The partitions of the power, which depend on the distribution function of D, vary strongly over several slowing down times. Self-consistent modelling of the distribution function with the SELFO-light code are presented and compared with experimental data from fast particle diagnostics.

  16. Achievement of Core Conditions for Alpha Heating in Direct-Drive Inertial Confinement Fusion

    NASA Astrophysics Data System (ADS)

    Bose, A.; Woo, K. M.; Betti, R.; Mangino, D.; Christopherson, A. R.; Theobald, W.; Campbell, E. M.; McCrory, R. L.; Regan, S. P.; Goncharov, V. N.; Sangster, T. C.; Forrest, C. J.; Glebov, V. Yu.; Knauer, J. P.; Marshall, F. J.; Stoeckl, C.; Nora, R.; Frenje, J. A.; Gatu Johnson, M.; Shvarts, D.

    2016-10-01

    It is shown for the first time that direct-drive implosions on the OMEGA laser have achieved core conditions that would lead to significant alpha heating at incident energies available at the National Ignition Facility (NIF) scale. The extrapolation of the experimental results from OMEGA to NIF energy assumes only that the implosion hydrodynamic efficiency is unchanged at higher energies. This approach is independent of the uncertainties in the physical mechanism that degrade implosions on OMEGA, and relies solely on a volumetric scaling of the experimentally observed core conditions. It is estimated that the current best-performing OMEGA implosion extrapolated to a 1.9-MJ laser driver with the same illumination configuration and laser-target coupling would produce 125 kJ of fusion energy with similar levels of alpha heating observed in current highest performing indirect-drive NIF implosions. This conclusion is reached using an analytic scaling as well as direct numerical simulations of energy-scaled targets. This material is based upon work supported by the Department of Energy National Nuclear Security Administration under Award Number DE-NA0001944.

  17. Alpha Heating and Burning Plasmas in Inertial Confinement Fusion

    NASA Astrophysics Data System (ADS)

    Betti, R.; Christopherson, A. R.; Bose, A.; Woo, K. M.

    2016-05-01

    Assessing the degree to which fusion alpha particles contribute to the fusion yield is essential to understanding the onset of the thermal runaway process of thermonuclear ignition. It is shown that in inertial confinement fusion, the yield enhancement due to alpha particle heating (before ignition occurs) depends on the generalized Lawson parameter that can be inferred from experimental observables. A universal curve valid for arbitrary laser-fusion targets shows the yield amplification due to alpha heating for a given value of the Lawson parameter. The same theory is used to determine the onset of the burning plasma regime when the alpha heating exceeds the compression work. This result can be used to assess the performance of current ignition experiments at the National Ignition Facility.

  18. Stand alone computer system to aid the development of Mirror Fusion Test Facility rf heating systems

    SciTech Connect

    Thomas, R.A.

    1983-12-01

    The Mirror Fusion Test Facility (MFTF-B) control system architecture requires the Supervisory Control and Diagnostic System (SCDS) to communicate with a LSI-11 Local Control Computer (LCC) that in turn communicates via a fiber optic link to CAMAC based control hardware located near the machine. In many cases, the control hardware is very complex and requires a sizable development effort prior to being integrated into the overall MFTF-B system. One such effort was the development of the Electron Cyclotron Resonance Heating (ECRH) system. It became clear that a stand alone computer system was needed to simulate the functions of SCDS. This paper describes the hardware and software necessary to implement the SCDS Simulation Computer (SSC). It consists of a Digital Equipment Corporation (DEC) LSI-11 computer and a Winchester/Floppy disk operating under the DEC RT-11 operating system. All application software for MFTF-B is programmed in PASCAL, which allowed us to adapt procedures originally written for SCDS to the SSC. This nearly identical software interface means that software written during the equipment development will be useful to the SCDS programmers in the integration phase.

  19. High-heat-flux testing of irradiated tungsten-based materials for fusion applications using infrared plasma arc lamps

    SciTech Connect

    Sabau, Adrian S.; Ohriner, Evan K.; Kiggans, Jim; Schaich, Charles R.; Ueda, Yoshio; Harper, David C.; Katoh, Yutai; Snead, Lance L.; Byun, Thak S.

    2014-11-01

    Testing of advanced materials and component mock-ups under prototypical fusion high-heat-flux conditions, while historically a mainstay of fusion research, has proved to be quite challenging, especially for irradiated materials. A new high-heat-flux–testing (HHFT) facility based on water-wall plasma arc lamps (PALs) is now introduced for materials and small-component testing. Two PAL systems, utilizing a 12 000°C plasma arc contained in a quartz tube cooled by a spiral water flow over the inside tube surface, provide maximum incident heat fluxes of 4.2 and 27 MW/m2 over areas of 9×12 and 1×10 cm2, respectively. This paper will present the overall design and implementation of a PAL-based irradiated material target station (IMTS). The IMTS is primarily designed for testing the effects of heat flux or thermal cycling on material coupons of interest, such as those for plasma-facing components. Temperature results are shown for thermal cycling under HHFT of tungsten coupon specimens that were neutron irradiated in HFIR. Finally, radiological surveys indicated minimal contamination of the 36×36×18 cm test section, demonstrating the capability of the new facility to handle irradiated specimens at high temperature.

  20. High-heat-flux testing of irradiated tungsten-based materials for fusion applications using infrared plasma arc lamps

    DOE PAGES

    Sabau, Adrian S.; Ohriner, Evan K.; Kiggans, Jim; ...

    2014-11-01

    Testing of advanced materials and component mock-ups under prototypical fusion high-heat-flux conditions, while historically a mainstay of fusion research, has proved to be quite challenging, especially for irradiated materials. A new high-heat-flux–testing (HHFT) facility based on water-wall plasma arc lamps (PALs) is now introduced for materials and small-component testing. Two PAL systems, utilizing a 12 000°C plasma arc contained in a quartz tube cooled by a spiral water flow over the inside tube surface, provide maximum incident heat fluxes of 4.2 and 27 MW/m2 over areas of 9×12 and 1×10 cm2, respectively. This paper will present the overall design andmore » implementation of a PAL-based irradiated material target station (IMTS). The IMTS is primarily designed for testing the effects of heat flux or thermal cycling on material coupons of interest, such as those for plasma-facing components. Temperature results are shown for thermal cycling under HHFT of tungsten coupon specimens that were neutron irradiated in HFIR. Finally, radiological surveys indicated minimal contamination of the 36×36×18 cm test section, demonstrating the capability of the new facility to handle irradiated specimens at high temperature.« less

  1. Alpha heating and burning plasmas in inertial confinement fusion

    SciTech Connect

    Betti, R.; Christopherson, A. R.; Spears, B. K.; Nora, R.; Bose, A.; Howard, J.; Woo, K. M.; Edwards, M. J.; Sanz, J.

    2015-06-01

    Estimating the level of alpha heating and determining the onset of the burning plasma regime is essential to finding the path towards thermonuclear ignition. In a burning plasma, the alpha heating exceeds the external input energy to the plasma. Using a simple model of the implosion, it is shown that a general relation can be derived, connecting the burning plasma regime to the yield enhancement due to alpha heating and to experimentally measurable parameters such as the Lawson ignition parameter. A general alpha-heating curve is found, independent of the target and suitable to assess the performance of all laser fusion experiments whether direct or indirect drive. The onset of the burning plasma regime inside the hot spot of current implosions on the National Ignition Facility requires a fusion yield of about 50 kJ.

  2. Critical heat flux investigations for fusion-relevant conditions with the use of a rastered electron beam apparatus

    SciTech Connect

    Koski, J.A.; Croessmann, C.D.

    1988-01-01

    With the use of a rastered electron beam apparatus, investigations of critical heat flux (CH) and associated noise, pressure and flow spectra have been completed for water-cooled test targets under conditions relevant to the design of high-heat-flux components for fusion energy applications. Targets tested were copper tubes with attached graphite armor tiles. Water flows with velocities ranging from 3 to 10 m/s were used, with axially uniform heat fluxes ranging from 10 to 60 MW/m/sup 2/ applied along only one side of the tube to simulate the heating pattern often encountered by plasma facing components in fusion applications. Targets included stainless steel twisted tapes mechanically locked into the tube bore to increase CH levels. Exit conditions typical of highly subcooled flow boiling were considered, e.g., exit qualities of about /minus/0.3, with exit pressures near 1 MPa, and exit temperatures in the 30 to 40 C range. Besides observation of CHF and the comparison to CHF correlations, the studies also examined possible means for predicting and preventing tube burnout. Diagnostics tried included acoustic amplitude and spectra in both the audible and above audible frequency ranges, exit pressure amplitude and spectra, and flow variations and spectra. During testing, signals from the diagnostics showed a large increase in amplitude before CHF occurred. 13 refs., 9 figs.

  3. Fusion Plasma Theory: Task 3, Auxiliary radiofrequency heating of tokamaks. Annual report, November 16, 1991--November 15, 1992

    SciTech Connect

    Scharer, J.E.

    1992-12-31

    The research performed under this grant during the past year has been concentrated on the following several key tokamak ICRF (Ion Cyclotron Range of Frequencies) coupling, heating and current drive issues: Efficient coupling during the L- to H- mode transition by analysis and computer simulation of ICRF antennas; analysis of ICRF cavity-backed coil antenna coupling to plasma edge profiles including fast and ion Bernstein wave coupling for heating and current drive; benchmarking the codes to compare with current JET, D-IIID and ASDEX experimental results and predictions for advanced tokamaks such as BPX and SSAT (Steady-State Advanced Tokamak); ICRF full-wave field solutions, power conservation, heating analyses and minority ion current drive; and the effects of fusion alpha particle or ion tail populations on the ICRF absorption. Research progress, publications, and conference and workshop presentations are summarized in this report.

  4. Investigation of heat transfer in liquid-metal flows under fusion-reactor conditions

    NASA Astrophysics Data System (ADS)

    Poddubnyi, I. I.; Pyatnitskaya, N. Yu.; Razuvanov, N. G.; Sviridov, V. G.; Sviridov, E. V.; Leshukov, A. Yu.; Aleskovskiy, K. V.; Obukhov, D. M.

    2016-12-01

    The effect discovered in studying a downward liquid-metal flow in vertical pipe and in a channel of rectangular cross section in, respectively, a transverse and a coplanar magnetic field is analyzed. In test blanket modules (TBM), which are prototypes of a blanket for a demonstration fusion reactor (DEMO) and which are intended for experimental investigations at the International Thermonuclear Experimental Reactor (ITER), liquid metals are assumed to fulfil simultaneously the functions of (i) a tritium breeder, (ii) a coolant, and (iii) neutron moderator and multiplier. This approach to testing experimentally design solutions is motivated by plans to employ, in the majority of the currently developed DEMO blanket projects, liquid metals pumped through pipes and/or rectangular channels in a transvers magnetic field. At the present time, experiments that would directly simulate liquid-metal flows under conditions of ITER TBM and/or DEMO blanket operation (irradiation with thermonuclear neutrons, a cyclic temperature regime, and a magnetic-field strength of about 4 to 10 T) are not implementable for want of equipment that could reproduce simultaneously the aforementioned effects exerted by thermonuclear plasmas. This is the reason why use is made of an iterative approach to experimentally estimating the performance of design solutions for liquid-metal channels via simulating one or simultaneously two of the aforementioned factors. Therefore, the investigations reported in the present article are of considerable topical interest. The respective experiments were performed on the basis of the mercury magneto hydrodynamic (MHD) loop that is included in the structure of the MPEI—JIHT MHD experimental facility. Temperature fields were measured under conditions of two- and one-sided heating, and data on averaged-temperature fields, distributions of the wall temperature, and statistical fluctuation features were obtained. A substantial effect of counter thermo gravitational

  5. NaOH-based high temperature heat-of-fusion thermal energy storage device

    NASA Technical Reports Server (NTRS)

    Cohen, B. M.; Rice, R. E.

    1978-01-01

    A material called Thermkeep, developed as a low-cost method for the storage of thermal energy for solar electric power generating systems is discussed. The storage device consists of an insulated cylinder containing Thermkeep in which coiled tubular heat exchangers are immersed. A one-tenth scale model of the design contains 25 heat-exchanger tubes and 1500 kg of Thermkeep. Its instrumentation includes thermocouples to measure internal Thermkeep temperatures, vessel surface, heated shroud surface, and pressure gauges to indicate heat-exchanger pressure drops. The test-circuit design is presented and experimental results are discussed.

  6. Proceedings of US/Japan workshop, Q219 on high heat flux components and plasma surface interactions for next fusion devices

    SciTech Connect

    Ulrickson, M.A.; Stevens, P.L.; Hino, T.; Hirohata, Y.

    1996-12-01

    This report contains the viewgraphs from the proceedings of US/Japan Workshop on High Heat Flux Components and Plasma Surface Interactions for Next Fusion Devices. Some of the general topics covered by this report are: PFC/PSI in tokamak and helical devices; development of high heat flux components; PSIS and plasma facing materials;tritium; and material damage.

  7. The design of a multimegawatt heat pipe radiator for an inertial fusion rocket powered manned Mars mission

    NASA Technical Reports Server (NTRS)

    Murray, K. A.

    1988-01-01

    A system of heat pipe radiators has been designed to provide waste heat rejection for an inertial fusion powered spacecraft capable of manned missions to other planets. The radiators are arrays of unfinned, arterial heat pipes operating at 1500 and 900 K. Liquid metal coolant carries up to 8000 MW of waste heat through feed pipes from on-board components (laser drivers and coil shield). The radiators do not rely on armor for protection from micrometeoroid penetration. An armored radiator design for this application with a 99 percent survivability would have a specific mass of 0.06 to 0.11 kg/kW at 1500 K. Instead, a segmentation of heat pipes is used, and bumpers are utilized to protect the feed pipes. This design reduces the specific mass to 0.015 to 0.04 kg/kW for the coil shield radiator (1500 K) and 0.06 to 0.12 kg/kW for the laser driver radiator (900 K).

  8. Experimental and analytical studies of high heat flux components for fusion experimental reactor

    NASA Astrophysics Data System (ADS)

    Araki, Masanori

    1993-03-01

    In this report, the experimental and analytical results concerning the development of plasma facing components of ITER are described. With respect to developing high heat removal structures for the divertor plates, an externally-finned swirl tube was developed based on the results of critical heat flux (CHF) experiments on various tube structures. As the result, the burnout heat flux, which also indicates incident CHF, of 41 (+/-) 1 MW/sq m was achieved in the externally-finned swirl tube. The applicability of existing CHF correlations based on uniform heating conditions was evaluated by comparing the CHF experimental data with the smooth and the externally-finned tubes under one-sided heating condition. As the results, experimentally determined CHF data for straight tube show good agreement, for the externally-finned tube, no existing correlations are available for prediction of the CHF. With respect to the evaluation of the bonds between carbon-based material and heat sink metal, results of brazing tests were compared with the analytical results by three dimensional model with temperature-dependent thermal and mechanical properties. Analytical results showed that residual stresses from brazing can be estimated by the analytical three directional stress values instead of the equivalent stress value applied. In the analytical study on the separatrix sweeping for effectively reducing surface heat fluxes on the divertor plate, thermal response of the divertor plate was analyzed under ITER relevant heat flux conditions and has been tested. As the result, it has been demonstrated that application of the sweeping technique is very effective for improvement in the power handling capability of the divertor plate and that the divertor mock-up has withstood a large number of additional cyclic heat loads.

  9. Fusion Plasma Theory Grant: Task 3, Auxiliary Radiofrequency Heating of Tokamaks. Annual report, November 16, 1992--November 15, 1993

    SciTech Connect

    Scharer, J.E.

    1993-06-01

    The research performed under this grant during the past year has been concentrated on the following several key tokamak ICRF (Ion Cyclotron Range of Frequencies) coupling, heating and current drive issues. We have made progress in developing a ``3-D`` cavity backed antenna array code to examine ICRF coupling to general plasma edge profiles. The effects of the finite antenna length and feeders as well as Faraday shield blade angle are being examined. We are also developing an analysis to examine large k{perpendicular}{rho} gyroradius interaction between alpha or beam particles and ICRF waves. This topic has important applications in the areas of ICRF heating for deuterium-tritium fusion plasmas, TAE modes, ash removal and minority ion current drive. Research progress, publications, and conference and workshop presentations are summarized in this report.

  10. Plasma Heating and Current Drive for Fusion Reactors

    NASA Astrophysics Data System (ADS)

    Holtkamp, Norbert

    2010-02-01

    ITER (in Latin ``the way'') is designed to demonstrate the scientific and technological feasibility of fusion energy. Fusion is the process by which two light atomic nuclei combine to form a heavier one and thus release energy. In the fusion process two isotopes of hydrogen - deuterium and tritium - fuse together to form a helium atom and a neutron. Thus fusion could provide large scale energy production without greenhouse effects; essentially limitless fuel would be available all over the world. The principal goals of ITER are to generate 500 megawatts of fusion power for periods of 300 to 500 seconds with a fusion power multiplication factor, Q, of at least 10. Q >= 10 (input power 50 MW / output power 500 MW). In a Tokamak the definition of the functionalities and requirements for the Plasma Heating and Current Drive are relevant in the determination of the overall plant efficiency, the operation cost of the plant and the plant availability. This paper summarise these functionalities and requirements in perspective of the systems under construction in ITER. It discusses the further steps necessary to meet those requirements. Approximately one half of the total heating will be provided by two Neutral Beam injection systems at with energy of 1 MeV and a beam power of 16 MW into the plasma. For ITER specific test facility is being build in order to develop and test the Neutral Beam injectors. Remote handling maintenance scheme for the NB systems, critical during the nuclear phase of the project, will be developed. In addition the paper will give an overview over the general status of ITER. )

  11. Material ejection and surface morphology changes during transient heat loading of tungsten as plasma-facing component in fusion devices

    NASA Astrophysics Data System (ADS)

    Suslova, A.; El-Atwani, O.; Harilal, S. S.; Hassanein, A.

    2015-03-01

    We investigated the effect of edge-localized mode like transient heat events on pristine samples for two different grades of deformed tungsten with ultrafine and nanocrystalline grains as potential candidates for plasma-facing components. Pulses from a laser beam with durations ∼1 ms and operating in the near infrared wavelength were used for simulating transient heat loading in fusion devices. We specifically focused on investigating and analysis of different mechanisms for material removal from the sample surface under repetitive transient heat loads. Several techniques were applied for analysing different mechanisms leading to material removal from the W surface under repetitive transient heat loads which include witness plates for collected ejected material, and subsequent analysis using x-ray photoelectron spectroscopy and scanning electron microscopy, visible imaging using fast-gated camera, and evaluating thermal emission from the particles using optical emission spectroscopy. Our results show a significantly improved performance of polycrystalline cold-rolled tungsten compared to tungsten produced using an orthogonal machining process under repetitive transient loads for a wide range of the power densities.

  12. Effect of Heat Treatment on Silicon Carbide Based Joining Materials for Fusion Energy

    SciTech Connect

    Lewinsohn, Charles A.; Jones, Russell H.; Nozawa, T.; Kotani, M.; Kishimoto, H.; Katoh, Y.; Kohyama, A.

    2001-10-01

    Two general approaches to obtaining silicon carbide-based joint materials were used. The first method relies on reactions between silicon and carbon to form silicon carbide, or to bond silicon carbide powders together. The second method consists of pyrolysing a polycarbosilane polymer to yield an amorphous, covalently bonded material. In order to assess the long-term durability of the joint materials, various heat treatments were performed and the effects on the mechanical properties of the joints were measured. Although the joints derived from the polycarbosilane polymer were not the strongest, the value of strength measured was not affected by heat treatment. On the other hand, the value of the strength of the reaction-based joints was affected by heat treatment, indicating the presence of residual stresses or unreacted material subsequent to processing. Further investigation of reaction-based joining should consist of detailed microscopic studies; however, continued study of joints derived from polymers is also warranted.

  13. Fast ignition when heating the central part of an inertial confinement fusion target by an ion beam

    SciTech Connect

    Gus’kov, S. Yu.; Zmitrenko, N. V.; Il’in, D. V.; Sherman, V. E.

    2014-11-15

    We investigate the ignition and burning of a precompressed laser fusion target when it is rapidly heated by an ion beam with the formation of a temperature peak in the central part of the target. We present the results of our comprehensive numerical simulations of the problem that include the following components: (1) the target compression under the action of a profiled laser pulse, (2) the heating of the compressed target with spatially nonuniform density and temperature distributions by a beam of high-energy ions, and (3) the burning of the target with the initial spatial density distribution formed at the instant of maximum target compression and the initial spatial temperature distribution formed as a result of the compressed-target heating by an ion beam. The dependences of the threshold energies of the igniting ion beam and the thermonuclear gain on the width of the Gaussian beam ion energy spectrum have been established. The peculiarities of fast ignition by an ion beam related to the spatial distribution of parameters for the target precompressed by a laser pulse are discussed.

  14. Simulation of Fusion Plasmas

    ScienceCinema

    Holland, Chris [UC San Diego, San Diego, California, United States

    2016-07-12

    The upcoming ITER experiment (www.iter.org) represents the next major milestone in realizing the promise of using nuclear fusion as a commercial energy source, by moving into the “burning plasma” regime where the dominant heat source is the internal fusion reactions. As part of its support for the ITER mission, the US fusion community is actively developing validated predictive models of the behavior of magnetically confined plasmas. In this talk, I will describe how the plasma community is using the latest high performance computing facilities to develop and refine our models of the nonlinear, multiscale plasma dynamics, and how recent advances in experimental diagnostics are allowing us to directly test and validate these models at an unprecedented level.

  15. Based on Landsat8 multi-resolution remote sensing image fusion of urban heat-island difference analysis

    NASA Astrophysics Data System (ADS)

    Zhang, Li; Zhou, Guoqing; Wang, Yuefeng; Ye, Siqi; Han, Caiyun

    2015-12-01

    Over the years, with the accelerating of city construction, urban heat-island effect has become increasingly significant.According to meteorological data of nearly ten years, some parts of the regional land surface temperature is higher, and then it influence people's introduction and living directly. At the same time it also affect the ecological environment of the earth.This article bases on the Landsat8 remote sensing image of 2014, through the different resolution of image fusion to analyze the differences surface temperature of the study area and forecast the future development tendency. Research finding: in different resolution, due to details of the objects reflecting obviously differences, affected by it, the surface temperature also exists obvious difference. The lower resolution, the surface temperature difference is smaller; on the contrary,the higher resolution makes surface temperature difference more significant. This shows that with the expansion of cities and the change of vegetation, water, the regional differences of heat-island effect is more obvious. In future development, how to coordinate and plan buildings, factories, vegetation, water, etc will affect the distribution of urban heat-island effect.

  16. Particle model for nonlocal heat transport in fusion plasmas.

    PubMed

    Bufferand, H; Ciraolo, G; Ghendrih, Ph; Lepri, S; Livi, R

    2013-02-01

    We present a simple stochastic, one-dimensional model for heat transfer in weakly collisional media as fusion plasmas. Energies of plasma particles are treated as lattice random variables interacting with a rate inversely proportional to their energy schematizing a screened Coulomb interaction. We consider both the equilibrium (microcanonical) and nonequilibrium case in which the system is in contact with heat baths at different temperatures. The model exhibits a characteristic length of thermalization that can be associated with an interaction mean free path and one observes a transition from ballistic to diffusive regime depending on the average energy of the system. A mean-field expression for heat flux is deduced from system heat transport properties. Finally, it is shown that the nonequilibrium steady state is characterized by long-range correlations.

  17. Design of a tunable 4-MW Free Electron Maser for heating fusion plasmas

    SciTech Connect

    Caplan, M.; Kamin, G.; Shang, C.C.; Lindquist, W.

    1993-09-01

    There is an ongoing program at the FOM institute, The Netherlands, to develop a 1-MW, long-pulse, 200-Ghz Free Electron Maser (FEM) using a DC accelerator system with depressed collector. We present an extrapolation of this design to more than 4MW of output microwave power in order to reduce the cost per kW and increase the power per module in a plasma heating system.

  18. Physics of Fusion Welding

    NASA Technical Reports Server (NTRS)

    Nunes, A. C., Jr.

    1986-01-01

    Applicabilities and limitations of three techniques analyzed. NASA technical memorandum discusses physics of electron-beam, gas/ tungsten-arc, and laser-beam welding. From comparison of capabilities and limitations of each technique with regard to various welding conditions and materials, possible to develop criteria for selecting best welding technique in specific application. All three techniques classified as fusion welding; small volume of workpiece melted by intense heat source. Heat source moved along seam, leaving in wake solid metal that joins seam edges together.

  19. Propagation of a laser beam in a time-varying waveguide. [plasma heating for controlled fusion

    NASA Technical Reports Server (NTRS)

    Chapman, J. M.; Kevorkian, J.

    1978-01-01

    The propagation of an axisymmetric laser beam in a plasma column having a radially parabolic electron density distribution is reported. For the case of an axially uniform waveguide it is found that the basic characteristics of alternating focusing and defocusing beams are maintained. However, the intensity distribution is changed at the foci and outer-beam regions. The features of paraxial beam propagation are discussed with reference to axially varying waveguides. Laser plasma coupling is considered noting the case where laser heating produces a density distribution radially parabolic near the axis and the energy absorbed over the focal length of the plasma is small. It is found that: (1) beam-propagation stability is governed by the relative magnitude of the density fluctuations existing in the axial variation of the waveguides due to laser heating, and (2) for beam propagation in a time-varying waveguide, the global instability of the propagation is a function of the initial fluctuation growth rate as compared to the initial time rate of change in the radial curvature of the waveguide.

  20. Transport of radial heat flux and second sound in fusion plasmas

    SciTech Connect

    Guercan, Oe. D.; Berionni, V.; Hennequin, P.; Morel, P.; Vermare, L.; Diamond, P. H.; Garbet, X.; Dif-Pradalier, G.; Kosuga, Y.

    2013-02-15

    Simple flux-gradient relations that involve time delay and radial coupling are discussed. Such a formulation leads to a rather simple description of avalanches and may explain breaking of gyroBohm transport scaling. The generalization of the flux-gradient relation (i.e., constitutive relation), which involve both time delay and spatial coupling, is derived from drift-kinetic equation, leading to kinetic definitions of constitutive elements such as the flux of radial heat flux. This allows numerical simulations to compute these cubic quantities directly. The formulation introduced here can be viewed as an extension of turbulence spreading to include the effect of spreading of cross-phase as well as turbulence intensity, combined in such a way to give the flux. The link between turbulence spreading and entropy production is highlighted. An extension of this formulation to general quasi-linear theory for the distribution function in the phase space of radial position and parallel velocity is also discussed.

  1. Microstructure evolution in the fusion welding of heat-treatable Al-Cu-Li alloys. Ph.D. Thesis

    SciTech Connect

    Hou, K.

    1994-01-01

    Aluminum alloys 2090 and 2195 and Al-2.5Cu were welded autogenously using the gas tungsten-arc (GTA) and CO2 laser beam (LB) welding processes. Relationships between microstructure and mechanical properties in the fusion zone (FZ) and the heat-affected zone (HAZ) in both the as-welded and the postweld heat-treated conditions were studied. Solute segregation due to non-equilibrium solidification in the FZ and its effect on precipitation after postweld aging was quantitatively investigated. After aging treatment, precipitates were found surrounding eutectic regions where higher solute content was measured. Fast cooling LB weld exhibited narrower solute enriched regions and narrower precipitate segregation zones (PSZ`s) adjacent to the eutectic. A partial recovery of strength and hardness in the FZ`s was achieved by postweld aging at 160 C and 190 C for 16 hours. A higher Li/Cu ratio in 2090 promoted the formation of uniformly distributed delta(prime) precipitates in the as-welded HAZ. An evident reduction in the FZ ductility occurred in the 2195 LB welds due to the existence of porosity and shrinkage cavities, and the constraint effect from narrower FZ`s. GTA welds in both 2090 and 2195 alloys exhibited a hardness recovery in the near HAZ, which was not obvious in the LB welds. Postweld aging enhanced this hardness variation. Overaging, dissolution and reprecipitation of various strengthening precipitates occurred in the different regions of the HAZ, and consequently induced the hardness variation. Higher heat inputs increased the HAZ width and enhanced the hardness increase in the near HAZ. Aged HAZ microstructure was affected by the precipitation in the as-welded condition. The formation of Li-containing precipitates in the GTA HAZ, especially alpha(prime) in Li-lean 2195, consumed Li from the matrix. Consequently, the precipitation of T1 was affected.

  2. Taming the heat flux problem: Advanced divertors towards fusion power

    SciTech Connect

    Kotschenreuther, M.; Mahajan, S.; Valanju, P. M.; Covele, B.; Waelbroeck, F. L.; Canik, John M.; LaBombard, Brian

    2015-09-11

    The next generation fusion machines are likely to face enormous heat exhaust problems. In addition to summarizing major issues and physical processes connected with these problems, we discuss how advanced divertors, obtained by modifying the local geometry, may yield workable solutions. We also point out that: (1) the initial interpretation of recent experiments show that the advantages, predicted, for instance, for the X-divertor (in particular, being able to run a detached operation at high pedestal pressure) correlate very well with observations, and (2) the X-D geometry could be implemented on ITER (and DEMOS) respecting all the relevant constraints. As a result, a roadmap for future research efforts is proposed.

  3. LiWall Fusion - The New Concept of Magnetic Fusion

    SciTech Connect

    L.E. Zakharov

    2011-01-12

    Utilization of the outstanding abilities of a liquid lithium layer in pumping hydrogen isotopes leads to a new approach to magnetic fusion, called the LiWall Fusion. It relies on innovative plasma regimes with low edge density and high temperature. The approach combines fueling the plasma by neutral injection beams with the best possible elimination of outside neutral gas sources, which cools down the plasma edge. Prevention of cooling the plasma edge suppresses the dominant, temperature gradient related turbulence in the core. Such an approach is much more suitable for controlled fusion than the present practice, relying on high heating power for compensating essentially unlimited turbulent energy losses.

  4. Review of fusion synfuels

    SciTech Connect

    Fillo, J.A.

    1980-01-01

    Thermonuclear fusion offers an inexhaustible source of energy for the production of hydrogen from water. Depending on design, electric generation efficiencies of approx. 40 to 60% and hydrogen production efficiencies by high-temperature electrolysis of approx. 50 to 65% are projected for fusion reactors using high-temperatures blankets. Fusion/coal symbiotic systems appear economically promising for the first generation of commercial fusion synfuels plants. Coal production requirements and the environmental effects of large-scale coal usage would be greatly reduced by a fusion/coal system. In the long term, there could be a gradual transition to an inexhaustible energy system based solely on fusion.

  5. Favorite Demonstrations: The Hair Roller as a Mind Bender: A Demonstration of Specific Heat and Heat of Fusion.

    ERIC Educational Resources Information Center

    Bonicamp, Judith M.; And Others

    1989-01-01

    Provides a demonstration for showing the usefulness of thermal principles to physical science students who have difficulty understanding conventional explanations. Outlines materials, procedures, discussion, and advantages of using this method. (RT)

  6. Kinetic advantage of controlled intermediate nuclear fusion

    SciTech Connect

    Guo Xiaoming

    2012-09-26

    The dominated process of controlled fusion is to let nuclei gain enough kinetic energy to overcome Coulomb barrier. As a result, a fusion scheme can consider two factors in its design: to increase kinetic energy of nuclei and to alter the Coulomb barrier. Cold Fusion and Hot fusion are all one-factor schemes while Intermediate Fusion is a twofactors scheme. This made CINF kinetically superior. Cold Fusion reduces deuteron-deuteron distance, addressing Coulomb barrier, and Hot Fusion heat up plasma into extreme high temperature, addressing kinetic energy. Without enough kinetic energy made Cold Fusion skeptical. Extreme high temperature made Hot Fusion very difficult to engineer. Because CIFN addresses both factors, CIFN is a more promising technique to be industrialized.

  7. Expression of a bioactive fusion protein of Escherichia coli heat-labile toxin B subunit to a synapsin peptide.

    PubMed

    Julia Scerbo, M; Bibolini, Mario J; Barra, José L; Roth, German A; Monferran, Clara G

    2008-06-01

    The B subunit of Escherichia coli heat-labile toxin (LTB) may function as an efficient carrier molecule for the delivery of genetically coupled antigens across the mucosal barrier. We constructed vectors for the expression of LTB and LTBSC proteins. LTBSC is a fusion protein that comprises the amino acid sequence from the C-domain of rat synapsin fused to the C-terminal end of LTB. Both constructions have a coding sequence for a 6His-tag fused in-frame. LTBSC was expressed in E. coli as inclusion bodies. The inclusion bodies were isolated and purified by Ni2+-chelating affinity chromatography under denaturing condition. Purified LTBSC was diluted in several refolding buffers to gain a soluble and biologically active protein. Refolded LTBSC assembled as an active oligomer which binds to the GM1 receptor in an enzyme-linked immunosorbent assay (ELISA). Soluble LTB in the E. coli lysate was also purified by Ni2+-chelating affinity chromatography and the assembled pentamer was able to bind with high affinity to GM1 in vitro. LTBSC and LTB were fed to rats and the ability to induce antigen-specific tolerance was tested. LTBSC inhibited the specific delayed-type hypersensitivity (DTH) response and induced decreased antigen-specific in vivo and in vitro cell proliferation more efficiently than LTB. Thus, the novel hybrid molecule LTBSC when orally delivered was able to elicit a systemic immune response. These results suggest that LTBSC could be suitable for exploring further therapeutic treatment of autoimmune inflammatory diseases involving antigens from central nervous system.

  8. Technical assessment of critical Plasma-Materials Interaction (PMI) and High Heat Flux (HHF) issues for alternative fusion concepts (AFCs)

    SciTech Connect

    Downing, J.N.

    1986-03-01

    A number of approaches to fusion energy are being pursued as alternative fusion concepts (AFCs). The goal of these systems is to provide a more desirable method of producing fusion energy than the mainline programs. Some of the AFCs have both a Low Power Density (LPD) option and a High Power Density (HPD) option. A summary of representative AFC programs and their associated PMI and HHF issues is followed by the technical assessment of the critical issues. These requirements are discussed relative to the mainline and/or HPD components. The HPD options are contrasted with a tabulation of the characteristics of components for the Reversed-Field Pinch (RFP), which is representative of the HPD concept.

  9. Magnetic fusion energy plasma interactive and high heat flux components. Volume II. Technical assessment of the critical issues and problem areas in high heat flux materials and component development

    SciTech Connect

    Abdou, M.A.; Boyd, R.D.; Easor, J.R.; Gauster, W.B.; Gordon, J.D.; Mattas, R.F.; Morgan, G.D.; Ulrickson, M.A,; Watson, R.D.; Wolfer, W.G,

    1984-06-01

    A technical assessment of the critical issues and problem areas for high heat flux materials and components (HHFMC) in magnetic fusion devices shows these problems to be of critical importance for the successful operation of near-term fusion experiments and for the feasibility and attractiveness of long-term fusion reactors. A number of subgroups were formed to assess the critical HHFMC issues along the following major lines: (1) source conditions, (2) systems integration, (3) materials and processes, (4) thermal hydraulics, (5) thermomechanical response, (6) electromagnetic response, (7) instrumentation and control, and (8) test facilities. The details of the technical assessment are presented in eight chapters. The primary technical issues and needs for each area are highlighted.

  10. Overview of fusion reactor safety

    SciTech Connect

    Cohen, S.; Crocker, J.G.

    1981-01-01

    Use of deuterium-tritium burning fusion reactors requires examination of several major safety and environmental issues: (1) tritium inventory control, (2) neutron activation of structural materials, fluid streams and reactor hall environment, (3) release of radioactivity from energy sources including lithium spill reactions, superconducting magnet stored energy release, and plasma disruptions, (4) high magnetic and electromagnetic fields associated with fusion reactor superconducting magnets and radio frequency heating devices, and (5) handling and disposal of radioactive waste. Early recognition of potential safety problems with fusion reactors provides the opportunity for improvement in design and materials to eliminate or greatly reduce these problems. With an early start in this endeavor, fusion should be among the lower risk technologies for generation of commercial electrical power.

  11. Determination of Heats of Fusion: Using Differential Scanning Calorimetry for the AP Chemistry Courses.

    ERIC Educational Resources Information Center

    Temme, Susan M.

    1995-01-01

    Describes an exercise designed to be used in an Advanced Placement (AP) chemistry course to accompany the study of thermodynamics. Uses Differential Scanning Calorimetry in teaching the concepts of thermochemistry and thermodynamics. (JRH)

  12. Measuring the Heats of Water.

    ERIC Educational Resources Information Center

    Hunt, James L.; Tegart, Tracy L.

    1994-01-01

    Uses common equipment (tea kettle and vacuum bottles) to precisely measure the specific heat, latent heat of fusion, and latent heat of vaporization of water. Provides descriptions for all three experiments. (MVL)

  13. Advanced latent heat of fusion thermal energy storage for solar power systems

    NASA Technical Reports Server (NTRS)

    Phillips, W. M.; Stearns, J. W.

    1985-01-01

    The use of solar thermal power systems coupled with thermal energy storage (TES) is being studied for both terrestrial and space applications. In the case of terrestrial applications, it was found that one or two hours of TES could shift the insolation peak (solar noon) to coincide with user peak loads. The use of a phase change material (PCM) is attractive because of the higher energy storage density which can be achieved. However, the use of PCM has also certain disadvantages which must be addressed. Proof of concept testing was undertaken to evaluate corrosive effects and thermal ratcheting effects in a slurry system. It is concluded that the considered alkali metal/alkali salt slurry approach to TES appears to be very viable, taking into account an elimination of thermal ratcheting in storage systems and the reduction of corrosive effects. The approach appears to be useful for an employment involving temperatures applicable to Brayton or Stirling cycles.

  14. Modeling and simulation support for ICRF heating of fusion plasmas. Annual report, 1990

    SciTech Connect

    1990-03-15

    Recent experimental, theoretical and computational results have shown the need and usefulness of a combined approach to the design, analysis and evaluation of ICH antenna configurations. The work at the University of Wisconsin (UW) in particular has shown that much needed information on the vacuum operation of ICH antennas can be obtained by a modest experimental and computational effort. These model experiments at UW and SAIC simulations have shown dramatically the potential for positive impact upon the ICRF program. Results of the UW-SAIC joint ICRF antenna analysis effort have been presented at several international meetings and numerous meetings in the United States. The PPPL bay M antenna has been modeled using the ARGUS code. The results of this effort are shown in Appendix C. SAIC has recently begun a collaboration with the ICRF antenna design and analysis group at ORNL. At present there are two separate projects underway. The first is associated with the simulation of and determination of the effect of adding slots in the antenna septum and side walls. The second project concerns the modeling and simulation of the ORNL folded waveguide (FWG) concept.

  15. Heat-transfer characteristics of flowing and stationary particle-bed-type fusion-reactor blankets

    SciTech Connect

    Nietert, R.E.

    1983-02-01

    The following five appendices are included: (1) physical properties of materials, (2) thermal entrance length Nusselt number variations, (3) stationary particle bed temperature variations, (4) falling bed experimental data and calculations, and (5) stationary bed experimental data and calculations. (MOW)

  16. Magnetic Fusion Energy Plasma Interactive and High Heat Flux Components: Volume 5, Technical assessment of critical issues in the steady state operation of fusion confinement devices

    SciTech Connect

    Not Available

    1988-01-01

    Critical issues for the steady state operation of plasma confinement devices exist in both the physics and technology fields of fusion research. Due to the wide range and number of these issues, this technical assessment has focused on the crucial issues associated with the plasma physics and the plasma interactive components. The document provides information on the problem areas that affect the design and operation of a steady state ETR or ITER type confinement device. It discusses both tokamaks and alternative concepts, and provides a survey of existing and planned confinement machines and laboratory facilities that can address the identified issues. A universal definition of steady state operation is difficult to obtain. From a physics point of view, steady state is generally achieved when the time derivatives approach zero and the operation time greatly exceeds the characteristic time constants of the device. Steady state operation for materials depends on whether thermal stress, creep, fatigue, radiation damage, or power removal are being discussed. For erosion issues, the fluence and availability of the machine for continuous operation are important, assuming that transient events such as disruptions do not limit the component lifetimes. The panel suggests, in general terms, that steady state requires plasma operation from 100 to 1000 seconds and an availability of more than a few percent, which is similar to the expectations for an ETR type device. The assessment of critical issues for steady state operation is divided into four sections: physics issues; technology issues; issues in alternative concepts; and devices and laboratory facilities that can address these problems.

  17. INTERACTION OF LASER RADIATION WITH MATTER. LASER PLASMA: Smoothing of ablation pressure nonuniformities in the laser-plasma corona during heating of laser fusion targets

    NASA Astrophysics Data System (ADS)

    Zhurovich, M. A.; Zhitkova, O. A.; Lebo, I. G.; Mikhailov, Yu A.; Sklizkov, G. V.; Starodub, Aleksandr N.; Tishkin, V. F.

    2009-06-01

    A method for smoothing ablation pressure nonuniformities during heating of laser fusion targets is described which utilises an extra laser pulse preceding the main pulse. Theoretical and experimental data are presented on heating of thin (3-10 μm) foils (simulating the target shell) by a spatially nonuniform laser beam. In the experiments, the laser pulse width at half maximum was 2 ns and the pulse energy was 2-30 J, which ensured a power density on the target surface from 1013 to 1014 W cm-2. The experimental data are analysed using two-dimensional numerical simulations. The experimental and simulation results demonstrate that this approach is sufficiently effective. The optimal laser prepulse parameters are determined.

  18. Genetic Fusions of a CFA/I/II/IV MEFA (Multiepitope Fusion Antigen) and a Toxoid Fusion of Heat-Stable Toxin (STa) and Heat-Labile Toxin (LT) of Enterotoxigenic Escherichia coli (ETEC) Retain Broad Anti-CFA and Antitoxin Antigenicity

    PubMed Central

    Ruan, Xiaosai; Sack, David A.; Zhang, Weiping

    2015-01-01

    Immunological heterogeneity has long been the major challenge in developing broadly effective vaccines to protect humans and animals against bacterial and viral infections. Enterotoxigenic Escherichia coli (ETEC) strains, the leading bacterial cause of diarrhea in humans, express at least 23 immunologically different colonization factor antigens (CFAs) and two distinct enterotoxins [heat-labile toxin (LT) and heat-stable toxin type Ib (STa or hSTa)]. ETEC strains expressing any one or two CFAs and either toxin cause diarrhea, therefore vaccines inducing broad immunity against a majority of CFAs, if not all, and both toxins are expected to be effective against ETEC. In this study, we applied the multiepitope fusion antigen (MEFA) strategy to construct ETEC antigens and examined antigens for broad anti-CFA and antitoxin immunogenicity. CFA MEFA CFA/I/II/IV [CVI 2014, 21(2):243-9], which carried epitopes of seven CFAs [CFA/I, CFA/II (CS1, CS2, CS3), CFA/IV (CS4, CS5, CS6)] expressed by the most prevalent and virulent ETEC strains, was genetically fused to LT-STa toxoid fusion monomer 3xSTaA14Q-dmLT or 3xSTaN12S-dmLT [IAI 2014, 82(5):1823-32] for CFA/I/II/IV-STaA14Q-dmLT and CFA/I/II/IV-STaN12S-dmLT MEFAs. Mice intraperitoneally immunized with either CFA/I/II/IV-STa-toxoid-dmLT MEFA developed antibodies specific to seven CFAs and both toxins, at levels equivalent or comparable to those induced from co-administration of the CFA/I/II/IV MEFA and toxoid fusion 3xSTaN12S-dmLT. Moreover, induced antibodies showed in vitro adherence inhibition activities against ETEC or E. coli strains expressing these seven CFAs and neutralization activities against both toxins. These results indicated CFA/I/II/IV-STa-toxoid-dmLT MEFA or CFA/I/II/IV MEFA combined with 3xSTaN12S-dmLT induced broadly protective anti-CFA and antitoxin immunity, and suggested their potential application in broadly effective ETEC vaccine development. This MEFA strategy may be generally used in multivalent

  19. Inertially confined fusion plasmas dominated by alpha-particle self-heating

    NASA Astrophysics Data System (ADS)

    Hurricane, O. A.; Callahan, D. A.; Casey, D. T.; Dewald, E. L.; Dittrich, T. R.; Döppner, T.; Haan, S.; Hinkel, D. E.; Berzak Hopkins, L. F.; Jones, O.; Kritcher, A. L.; Le Pape, S.; Ma, T.; Macphee, A. G.; Milovich, J. L.; Moody, J.; Pak, A.; Park, H.-S.; Patel, P. K.; Ralph, J. E.; Robey, H. F.; Ross, J. S.; Salmonson, J. D.; Spears, B. K.; Springer, P. T.; Tommasini, R.; Albert, F.; Benedetti, L. R.; Bionta, R.; Bond, E.; Bradley, D. K.; Caggiano, J.; Celliers, P. M.; Cerjan, C.; Church, J. A.; Dylla-Spears, R.; Edgell, D.; Edwards, M. J.; Fittinghoff, D.; Barrios Garcia, M. A.; Hamza, A.; Hatarik, R.; Herrmann, H.; Hohenberger, M.; Hoover, D.; Kline, J. L.; Kyrala, G.; Kozioziemski, B.; Grim, G.; Field, J. E.; Frenje, J.; Izumi, N.; Gatu Johnson, M.; Khan, S. F.; Knauer, J.; Kohut, T.; Landen, O.; Merrill, F.; Michel, P.; Moore, A.; Nagel, S. R.; Nikroo, A.; Parham, T.; Rygg, R. R.; Sayre, D.; Schneider, M.; Shaughnessy, D.; Strozzi, D.; Town, R. P. J.; Turnbull, D.; Volegov, P.; Wan, A.; Widmann, K.; Wilde, C.; Yeamans, C.

    2016-08-01

    Alpha-particle self-heating, the process of deuterium-tritium fusion reaction products depositing their kinetic energy locally within a fusion reaction region and thus increasing the temperature in the reacting region, is essential for achieving ignition in a fusion system. Here, we report new inertial confinement fusion experiments where the alpha-particle heating of the plasma is dominant with the fusion yield produced exceeding the fusion yield from the work done on the fuel (pressure times volume change) by a factor of two or more. These experiments have achieved the highest yield (26 +/- 0.5 kJ) and stagnation pressures (≍220 +/- 40 Gbar) of any facility-based inertial confinement fusion experiments, although they are still short of the pressures required for ignition on the National Ignition Facility (~300-400 Gbar). These experiments put us in a new part of parameter space that has not been extensively studied so far because it lies between the no-alpha-particle-deposition regime and ignition.

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

    PubMed

    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.

  1. Numerical Solution of the Electron Heat Transport Equation and Physics-Constrained Modeling of the Thermal Conductivity via Sequential Quadratic Programming Optimization in Nuclear Fusion Plasmas

    NASA Astrophysics Data System (ADS)

    Paloma, Cynthia S.

    The plasma electron temperature (Te) plays a critical role in a tokamak nu- clear fusion reactor since temperatures on the order of 108K are required to achieve fusion conditions. Many plasma properties in a tokamak nuclear fusion reactor are modeled by partial differential equations (PDE's) because they depend not only on time but also on space. In particular, the dynamics of the electron temperature is governed by a PDE referred to as the Electron Heat Transport Equation (EHTE). In this work, a numerical method is developed to solve the EHTE based on a custom finite-difference technique. The solution of the EHTE is compared to temperature profiles obtained by using TRANSP, a sophisticated plasma transport code, for specific discharges from the DIII-D tokamak, located at the DIII-D National Fusion Facility in San Diego, CA. The thermal conductivity (also called thermal diffusivity) of the electrons (Xe) is a plasma parameter that plays a critical role in the EHTE since it indicates how the electron temperature diffusion varies across the minor effective radius of the tokamak. TRANSP approximates Xe through a curve-fitting technique to match experimentally measured electron temperature profiles. While complex physics-based model have been proposed for Xe, there is a lack of a simple mathematical model for the thermal diffusivity that could be used for control design. In this work, a model for Xe is proposed based on a scaling law involving key plasma variables such as the electron temperature (Te), the electron density (ne), and the safety factor (q). An optimization algorithm is developed based on the Sequential Quadratic Programming (SQP) technique to optimize the scaling factors appearing in the proposed model so that the predicted electron temperature and magnetic flux profiles match predefined target profiles in the best possible way. A simulation study summarizing the outcomes of the optimization procedure is presented to illustrate the potential of the

  2. Two Horizons of Fusion

    ERIC Educational Resources Information Center

    Lo, Mun Ling; Chik, Pakey Pui Man

    2016-01-01

    In this paper, we aim to differentiate the internal and external horizons of "fusion." "Fusion" in the internal horizon relates to the structure and meaning of the object of learning as experienced by the learner. It clarifies the interrelationships among an object's critical features and aspects. It also illuminates the…

  3. FINAL Report on Analysis and direct numerical simulation of RF heating processes and advanced computational methods for fusion application

    SciTech Connect

    Cary, John R.

    2015-02-23

    This completes the description of the work done under the above referenced grant. In brief, we have discovered many nonlinear effects, frequency doubling, nonlinear decays, that can prevent effective use of EBWs for plasma heating.

  4. Heat Source - Materials Interactions during Fusion Welding.

    DTIC Science & Technology

    1982-04-30

    under these p conditions would be linear regardless of the natures of these compounds. In this respect, the oxygen pressure plots advocated herein...Dependence of the Equilibrium Oxygen Pressure in Metal Oxide Systems A. Block-Bolten and D. R. Sadoway 100 ___Accescion Fr N~TI GRA&I DTIC TAB...report describes work performed in the MIT Welding Laboratory under Office of Naval Research sponsorship. The work ii generally fundamental in nature

  5. Heat deposition rate measurements using a graphite quasi-adiabatic calorimeter and thermoluminescent dosimeters in a fusion environment of the LOTUS facility

    SciTech Connect

    Joneja, O.P.; Rosselet, M.; Luethi, A.; Ligou, J.; Anand, R.P.; Buchillier, T.

    1995-11-01

    Heat deposition rate measurements are made by an extremely sensitive quasi-adiabatic graphite calorimeter and thermoluminescent dosimeters (TLDs) in the fusion environment of the LOTUS facility. The reproducibility of these measurements is found to be better than 1% for a dose rate more than 60 cGy/min and better than 3.8% for dose rates in the range of 6 to 60 cGy/min. The heating rates are found to vary linearly with neutron source strength. The calculation to experiment (C/E) for the bare calorimeter is found to be 1.05, whereas inside the graphite block, C/E varies from 1.11 to 1.32. These measurements are analyzed by the MCNP Monte Carlo neutron and photon transport code using the BMCCS2, PHOTXS2, and EL2 cross-section libraries. The influence of wall-returned neutrons and gammas is found to be negligible. A detailed data treatment is done with the TLD outputs to arrive at the gamma heating component at different locations in the graphite by employing the Burlin theory. The gamma production is found to be well represented in the calculations. On the other hand, measured and calculated net nuclear heating in the graphite differ considerably. A downward revision of the neutron kerma factor would be desirable. 23 refs., 8 figs., 4 tabs.

  6. Effect of Heat Treatment on Residual Stresses in the Zone of Fusion of Austenitic and Vessel Steels

    NASA Astrophysics Data System (ADS)

    Khlybov, A. A.

    2016-11-01

    The effect of heat treatment on the structure and physical and mechanical properties of flat specimens cut from a massive billet from steel 15Kh2MFA with an austenitic facing on one side is studied. The hardness and the microhardness of the specimens are determined. Acoustic and x-ray studies are performed. The causes of residual stresses giving rise to deformation and formation of cracks in the faced steel are established. Ways to solve the problem are suggested.

  7. Irradiation creep and swelling of the U.S. fusion heats of HT9 and 9Cr-1Mo to 208 dpa at {approximately}400{degree}C

    SciTech Connect

    Toloczko, M.B.; Garner, F.A.; Eiholzer, C.R.

    1993-09-01

    Ferritic-martensite steels are being considered for structural applications in fusion reactors. In order to provide data on the response of such steels to radiation, a series of experiments have been conducted in FFTF. Here, the irradiation creep and swelling behaviors of the fusion heats of HT9 and 9Cr-1Mo at {approximately}400 C have been measured to exposures as large as 208 dpa, using both diametral and density measurements of helium-pressurized creep tubes. Void swelling was found in both alloys at 208 dpa to occur at rates of 0.012%/dpa or less, with the swelling of HT9 exhibiting a larger degree of stress enhancement than 9Cr-1Mo. The creep rate of HT9 is rather nonlinear in its response to hoop stress level in the range 0--200 MPa, but 9Cr-1Mo exhibits only slightly greater than linear behavior with stress level. The creep-swelling coupling coefficients for 9Cr-1Mo are consistent with values obtained for other steels.

  8. Glossary of fusion energy

    NASA Astrophysics Data System (ADS)

    Whitson, M. O.

    1985-02-01

    The Glossary of Fusion Energy is an attempt to present a concise, yet comprehensive collection of terms that may be beneficial to scientists and laymen who are directly or tangentially concerned with this burgeoning energy enterprise. Included are definitions of terms in theoretical plasma physics, controlled thermonuclear fusion, and some related physics concepts. Also, short descriptions of some of the major thermonuclear experiments currently under way in the world today are included.

  9. The fusion of Toxoplasma gondii SAG1 vaccine candidate to Leishmania infantum heat shock protein 83-kDa improves expression levels in tobacco chloroplasts.

    PubMed

    Albarracín, Romina M; Becher, Melina Laguía; Farran, Inmaculada; Sander, Valeria A; Corigliano, Mariana G; Yácono, María L; Pariani, Sebastián; López, Edwin Sánchez; Veramendi, Jon; Clemente, Marina

    2015-05-01

    Chloroplast transformation technology has emerged as an alternative platform offering many advantages over nuclear transformation. SAG1 is the main surface antigen of the intracellular parasite Toxoplasma gondii and a promising candidate to produce an anti-T. gondii vaccine. The aim of this study was to investigate the expression of SAG1 using chloroplast transformation technology in tobacco plants. In order to improve expression in transplastomic plants, we also expressed the 90-kDa heat shock protein of Leishmania infantum (LiHsp83) as a carrier for the SAG1 antigen. SAG1 protein accumulation in transplastomic plants was approximately 0.1-0.2 μg per gram of fresh weight (FW). Fusion of SAG1 to LiHsp83 significantly increased the level of SAG1 accumulation in tobacco chloroplasts (by up to 500-fold). We also evaluated the functionality of the chLiHsp83-SAG1. Three human seropositive samples reacted with SAG1 expressed in transplastomic chLiHsp83-SAG1 plants. Oral immunization with chLiHsp83-SAG1 elicited a significant reduction of the cyst burden that correlated with an increase of SAG1-specific antibodies. We propose the fusion of foreign proteins to LiHsp83 as a novel strategy to increase the expression level of the recombinant proteins using chloroplast transformation technology, thus addressing one of the current challenges for this approach in antigen protein production.

  10. Heat resistant reduced activation 12% Cr steel of 16Cr12W2VTaB type-advanced structural material for fusion and fast breeder power reactors

    NASA Astrophysics Data System (ADS)

    Ioltukhovskiy, A. G.; Leonteva-Smirnova, M. V.; Solonin, M. I.; Chernov, V. M.; Golovanov, V. N.; Shamardin, V. K.; Bulanova, T. M.; Povstyanko, A. V.; Fedoseev, A. E.

    2002-12-01

    Heat resistant 12% Cr steels of the 16Cr12W2VTaB type (12Cr-2W-V-Ta-B-0.16C) provide a reduced activation material that can be used as a structural material for fusion and fast breeder reactors. The composition under study meets scientific and engineering requirements and has an optimal base element composition to provide a δ-ferrite content of no more than 20%. It also has a minimum quantity of low melting impurity elements and non-metallic inclusions. Short-term tensile properties for the steel tested to 700 °C are provided after the standard heat treatment (normalization, temper). Rupture strength and creep properties for the steel depending on the initial heat treatment conditions are also given. The microstructural stability of the 16Cr12W2VTaB type steel at temperatures up to 650 °C is predicted to be good, and the properties of the steel after irradiation in BOR-60 are demonstrated.

  11. Probing Reliability of Transport Phenomena Based Heat Transfer and Fluid Flow Analysis in Autogeneous Fusion Welding Process

    NASA Astrophysics Data System (ADS)

    Bag, S.; de, A.

    2010-09-01

    The transport phenomena based heat transfer and fluid flow calculations in weld pool require a number of input parameters. Arc efficiency, effective thermal conductivity, and viscosity in weld pool are some of these parameters, values of which are rarely known and difficult to assign a priori based on the scientific principles alone. The present work reports a bi-directional three-dimensional (3-D) heat transfer and fluid flow model, which is integrated with a real number based genetic algorithm. The bi-directional feature of the integrated model allows the identification of the values of a required set of uncertain model input parameters and, next, the design of process parameters to achieve a target weld pool dimension. The computed values are validated with measured results in linear gas-tungsten-arc (GTA) weld samples. Furthermore, a novel methodology to estimate the overall reliability of the computed solutions is also presented.

  12. Heat generation above break-even from laser-induced fusion in ultra-dense deuterium

    SciTech Connect

    Holmlid, Leif

    2015-08-15

    Previous results from laser-induced processes in ultra-dense deuterium D(0) give conclusive evidence for ejection of neutral massive particles with energy >10 MeV u{sup −1}. Such particles can only be formed from nuclear processes like nuclear fusion at the low laser intensity used. Heat generation is of interest for future fusion energy applications and has now been measured by a small copper (Cu) cylinder surrounding the laser target. The temperature rise of the Cu cylinder is measured with an NTC resistor during around 5000 laser shots per measured point. No heating in the apparatus or the gas feed is normally used. The fusion process is suboptimal relative to previously published studies by a factor of around 10. The small neutral particles H{sub N}(0) of ultra-dense hydrogen (size of a few pm) escape with a substantial fraction of the energy. Heat loss to the D{sub 2} gas (at <1 mbar pressure) is measured and compensated for under various conditions. Heat release of a few W is observed, at up to 50% higher energy than the total laser input thus a gain of 1.5. This is uniquely high for the use of deuterium as fusion fuel. With a slightly different setup, a thermal gain of 2 is reached, thus clearly above break-even for all neutronicity values possible. Also including the large kinetic energy which is directly measured for MeV particles leaving through a small opening gives a gain of 2.3. Taking into account the lower efficiency now due to the suboptimal fusion process, previous studies indicate a gain of at least 20 during long periods.

  13. Primary heat transfer loop design for the Cascade inertial confinement fusion reactor

    SciTech Connect

    Murray, K.A.; McDowell, M.W.

    1984-05-01

    This study investigates a heat exchanger and balance of plant design to accompany the Cascade inertial confinement fusion reaction chamber concept. The concept uses solid Li/sub 2/O or other lithium-ceramic granules, held to the wall of a rotating reaction chamber by centrifugal action, as a tritium breeding blanket and first wall protection. The Li/sub 2/O granules enter the chamber at 800 K and exit at 1200 K after absorbing the thermal energy produced by the fusion process.

  14. Differences between single-side and uniform heating for fusion applications

    SciTech Connect

    Boyd, R.D.; Meng, X.

    1994-12-31

    Many international engineering activities are under way to support fusion reactor implementation for the production of economical energy in the distant future. Among the many key technological issues is the development of plasma-facing components for the International Thermonuclear Experimental Reactor (ITER) and the related engineering design activity. Such components will be exposed to single-side (i.e., internal flow channels will be heated externally from one side only) heat flux ranging from 0.1 to 10.0 MW/m{sup 2} over lengths up to 0.3 m. Although other heat-transfer techniques such as liquid-metal and high-velocity-helium cooling are being seriously considered, subcooled flow boiling (with water) is the leading contender for high heat-flux fusion accommodation (HHFFA). Accordingly, interest must be focused on both the local heat transfer and the critical heat-flux (CHF) phenomena. However, irrespective of the convective fluid used (helium, water, or liquid metal) the advantages and adverse consequences associated with single-side heating must be explored and accommodated in future component designs.

  15. Peaceful Uses of Fusion

    DOE R&D Accomplishments Database

    Teller, E.

    1958-07-03

    Applications of thermonuclear energy for peaceful and constructive purposes are surveyed. Developments and problems in the release and control of fusion energy are reviewed. It is pointed out that the future of thermonuclear power reactors will depend upon the construction of a machine that produces more electric energy than it consumes. The fuel for thermonuclear reactors is cheap and practically inexhaustible. Thermonuclear reactors produce less dangerous radioactive materials than fission reactors and, when once brought under control, are not as likely to be subject to dangerous excursions. The interaction of the hot plasma with magnetic fields opens the way for the direct production of electricity. It is possible that explosive fusion energy released underground may be harnessed for the production of electricity before the same feat is accomplished in controlled fusion processes. Applications of underground detonations of fission devices in mining and for the enhancement of oil flow in large low-specific-yield formations are also suggested.

  16. Ultra-wideband coaxial hybrid coupler for load resilient ion cyclotron range of frequency heating at fusion plasmas

    SciTech Connect

    Kim, H. J.; Bae, Y. S.; Yang, H. L.; Kwak, J.-G.; Wang, S. J.; Kim, B. K.; Choi, J. J.

    2012-06-25

    We designed a high power and ultra-wideband two-section 3 dB coaxial hybrid coupler for load resilient ion cyclotron range of frequency heating by configuring asymmetric impedance matching using a three-dimensional simulation code, hfss. By adjusting the characteristic impedances of main and coupled lines of the hybrid coupler, we realized that the bandwidth of the proposed circuit is not only wider than that of a conventional three-section coupler, but also that the bandwidth is almost twice as wide compared to the conventional two-section hybrid coupler while maintaining the identical overall size.

  17. A fusion of minds

    NASA Astrophysics Data System (ADS)

    Corfield, Richard

    2013-02-01

    Mystery still surrounds the visit of the astronomer Sir Bernard Lovell to the Soviet Union in 1963. But his collaboration - and that of other British scientists - eased geopolitical tensions at the height of the Cold War and paved the way for today's global ITER fusion project, as Richard Corfield explains.

  18. Fusion

    NASA Astrophysics Data System (ADS)

    Herman, Robin

    1990-10-01

    The book abounds with fascinating anecdotes about fusion's rocky path: the spurious claim by Argentine dictator Juan Peron in 1951 that his country had built a working fusion reactor, the rush by the United States to drop secrecy and publicize its fusion work as a propaganda offensive after the Russian success with Sputnik; the fortune Penthouse magazine publisher Bob Guccione sank into an unconventional fusion device, the skepticism that met an assertion by two University of Utah chemists in 1989 that they had created "cold fusion" in a bottle. Aimed at a general audience, the book describes the scientific basis of controlled fusion--the fusing of atomic nuclei, under conditions hotter than the sun, to release energy. Using personal recollections of scientists involved, it traces the history of this little-known international race that began during the Cold War in secret laboratories in the United States, Great Britain and the Soviet Union, and evolved into an astonishingly open collaboration between East and West.

  19. Functional Pentameric Formation via Coexpression of the Escherichia coli Heat-Labile Enterotoxin B Subunit and Its Fusion Protein Subunit with a Neutralizing Epitope of ApxIIA Exotoxin Improves the Mucosal Immunogenicity and Protection against Challenge by Actinobacillus pleuropneumoniae▿

    PubMed Central

    Kim, Jung-Mi; Park, Seung-Moon; Kim, Jung-Ae; Park, Jin-Ah; Yi, Min-Hee; Kim, Nan-Sun; Bae, Jong-Lye; Park, Sung Goo; Jang, Yong-Suk; Yang, Moon-Sik; Kim, Dae-Hyuk

    2011-01-01

    A coexpression strategy in Saccharomyces cerevisiae using episomal and integrative vectors for the Escherichia coli heat-labile enterotoxin B subunit (LTB) and a fusion protein of an ApxIIA toxin epitope produced by Actinobacillus pleuropneumoniae coupled to LTB, respectively, was adapted for the hetero-oligomerization of LTB and the LTB fusion construct. Enzyme-linked immunosorbent assay (ELISA) with GM1 ganglioside indicated that the LTB fusion construct, along with LTB, was oligomerized to make the functional heteropentameric form, which can bind to receptors on the mucosal epithelium. The antigen-specific antibody titer of mice orally administered antigen was increased when using recombinant yeast coexpressing the pentameric form instead of recombinant yeast expressing either the LTB fusion form or antigen alone. Better protection against challenge infection with A. pleuropneumoniae was also observed for coexpression in recombinant yeast compared with others. The present study clearly indicated that the coexpression strategy enabled the LTB fusion construct to participate in the pentameric formation, resulting in an improved induction of systemic and mucosal immune responses. PMID:22030372

  20. Proceedings of 1999 U.S./Japan Workshop (99FT-05) On High Heat Flux Components and Plasma Surface Interactions for Next Fusion Devices

    SciTech Connect

    NYGREN,RICHARD E.; STAVROS,DIANA T.

    2000-06-01

    The 1999 US-Japan Workshop on High Heat Flux Components and Plasma Surface Interactions in Next Step Fusion Devices was held at the St. Francis Hotel in Santa Fe, New Mexico, on November 1-4, 1999. There were 42 presentations as well as discussion on technical issues and planning for future collaborations. The participants included 22 researchers from Japan and the United States as well as seven researchers from Europe and Russia. There have been important changes in the programs in both the US and Japan in the areas of plasma surface interactions and plasma facing components. The US has moved away from a strong focus on the ITER Project and has introduced new programs on use of liquid surfaces for plasma facing components, and operation of NSTX has begun. In Japan, the Large Helical Device began operation. This is the first large world-class confinement device operating in a magnetic configuration different than a tokamak. In selecting the presentations for this workshop, the organizers sought a balance between research in laboratory facilities or confinement devices related to plasma surface interactions and experimental research in the development of plasma facing components. In discussions about the workshop itself, the participants affirmed their preference for a setting where ''work-in-progress'' could be informally presented and discussed.

  1. Fusion rates for hydrogen isotopic molecules of relevance for 'cold fusion'

    NASA Astrophysics Data System (ADS)

    Szalewicz, K.; Morgan, J. D., III; Monkhorst, H. J.

    1989-09-01

    In response to the recent announcements of evidence for room-temperature fusion in the electrolysis of D2O, an analysis is presented of how the fusion rate depends on the reduced mass of the fusing nuclei, the effective mass of a 'heavy' electron, and the degree of vibrational excitation. The results have been obtained both by accurately solving the Schroedinger equation for the hydrogen molecule and by using the WKB approximation. It is found that in light of the reported d-d fusion rate, the excess heat in the experiment by Fleischmann, Pons, and Hawkins is difficult to explain in terms of conventional nuclear processes.

  2. Effect of Fuelling Depth on the Fusion Performance and Particle Confinement of a Fusion Reactor

    NASA Astrophysics Data System (ADS)

    Wang, Shijia; Wang, Shaojie

    2016-12-01

    The fusion performance and particle confinement of an international thermonuclear experimental reactor (ITER)-like fusion device have been modeled by numerically solving the energy transport equation and the particle transport equation. The effect of fuelling depth has been investigated. The plasma is primarily heated by the fusion produced alpha particles and the loss process of particles and energy in the scrape-off layer has been taken into account. To study the effect of fuelling depth on fusion performance, the ITERH-98P(y,2) scaling law has been used to evaluate the transport coefficients. It is shown that the particle confinement and fusion performance are significantly dependent on the fuelling depth. Deviation of 10% of the minor radius on fuelling depth can make the particle confinement change by ∼ 61% and the fusion performance change by ∼ 108%. The enhancement of fusion performance is due to the better particle confinement induced by deeper particle fuelling. supported by National Natural Science Foundation of China (Nos. 11175178 and 11375196) and the National Magnetic Confinement Fusion Science Program of China (No. 2014GB113000)

  3. Physics of laser fusion. Vol. I. Theory of the coronal plasma in laser-fusion targets

    SciTech Connect

    Max, C.E.

    1981-12-01

    This monograph deals with the physics of the coronal region in laser fusion targets. The corona consists of hot plasma which has been evaporated from the initially solid target during laser heating. It is in the corona that the laser light is absorbed by the target, and the resulting thermal energy is conducted toward cold high-density regions, where ablation occurs. The topics to be discussed are theoretical mechanisms for laser light absorption and reflection, hot-electron production, and the physics of heat conduction in laser-produced plasmas. An accompanying monograph by H. Ahlstrom (Vol.II) reviews the facilities, diagnostics, and data from recent laser fusion experiments.

  4. Heat-precipitation allows the efficient purification of a functional plant-derived malaria transmission-blocking vaccine candidate fusion protein.

    PubMed

    Beiss, Veronique; Spiegel, Holger; Boes, Alexander; Kapelski, Stephanie; Scheuermayer, Matthias; Edgue, Gueven; Sack, Markus; Fendel, Rolf; Reimann, Andreas; Schillberg, Stefan; Pradel, Gabriele; Fischer, Rainer

    2015-07-01

    Malaria is a vector-borne disease affecting more than two million people and accounting for more than 600,000 deaths each year, especially in developing countries. The most serious form of malaria is caused by Plasmodium falciparum. The complex life cycle of this parasite, involving pre-erythrocytic, asexual and sexual stages, makes vaccine development cumbersome but also offers a broad spectrum of vaccine candidates targeting exactly those stages. Vaccines targeting the sexual stage of P. falciparum are called transmission-blocking vaccines (TBVs). They do not confer protection for the vaccinated individual but aim to reduce or prevent the transmission of the parasite within a population and are therefore regarded as an essential tool in the fight against the disease. Malaria predominantly affects large populations in developing countries, so TBVs need to be produced in large quantities at low cost. Combining the advantages of eukaryotic expression with a virtually unlimited upscaling potential and a good product safety profile, plant-based expression systems represent a suitable alternative for the production of TBVs. We report here the high level (300 μg/g fresh leaf weight (FLW)) transient expression in Nicotiana benthamiana leaves of an effective TBV candidate based on a fusion protein F0 comprising Pfs25 and the C0-domain of Pfs230, and the implementation of a simple and cost-effective heat treatment step for purification that yields intact recombinant protein at >90% purity with a recovery rate of >70%. The immunization of mice clearly showed that antibodies raised against plant-derived F0 completely blocked the formation of oocysts in a malaria transmission-blocking assay (TBA) making F0 an interesting TBV candidate or a component of a multi-stage malaria vaccine cocktail.

  5. Economic potential of inertial fusion

    SciTech Connect

    Nuckolls, J.H.

    1984-04-01

    Beyond the achievement of scientific feasibility, the key question for fusion energy is: does it have the economic potential to be significantly cheaper than fission and coal energy. If fusion has this high economic potential then there are compelling commercial and geopolitical incentives to accelerate the pace of the fusion program in the near term, and to install a global fusion energy system in the long term. Without this high economic potential, fusion's success depends on the failure of all alternatives, and there is no real incentive to accelerate the program. If my conjectures on the economic potential of inertial fusion are approximately correct, then inertial fusion energy's ultimate costs may be only half to two-thirds those of advanced fission and coal energy systems. Relative cost escalation is not assumed and could increase this advantage. Both magnetic and inertial approaches to fusion potentially have a two-fold economic advantage which derives from two fundamental properties: negligible fuel costs and high quality energy which makes possible more efficient generation of electricity. The wining approach to fusion may excel in three areas: electrical generating efficiency, minimum material costs, and adaptability to manufacture in automated factories. The winning approach must also rate highly in environmental potential, safety, availability factor, lifetime, small 0 and M costs, and no possibility of utility-disabling accidents.

  6. High heat flux issues for plasma-facing components in fusion reactors

    NASA Astrophysics Data System (ADS)

    Watson, Robert D.

    1993-02-01

    Plasma facing components in tokamak fusion reactors are faced with a number of difficult high heat flux issues. These components include: first wall armor tiles, pumped limiters, diverter plates, rf antennae structure, and diagnostic probes. Peak heat fluxes are 15 - 30 MW/m2 for diverter plates, which will operate for 100 - 1000 seconds in future tokamaks. Disruption heat fluxes can approach 100,000 MW/m2 for 0.1 ms. Diverter plates are water-cooled heat sinks with armor tiles brazed on to the plasma facing side. Heat sink materials include OFHC, GlidcopTM, TZM, Mo-41Re, and niobium alloys. Armor tile materials include: carbon fiber composites, beryllium, silicon carbide, tungsten, and molybdenum. Tile thickness range from 2 - 10 mm, and heat sinks are 1 - 3 mm. A twisted tape insert is used to enhance heat transfer and increase the burnout safety margin from critical heat flux limits to 50 - 60 MW/m2 with water at 10 m/s and 4 MPa. Tests using rastered electron beams have shown thermal fatigue failures from cracks at the brazed interface between tiles and the heat sink after only 1000 cycles at 10 - 15 MW/m2. These fatigue lifetimes need to be increased an order of magnitude to meet future requirements. Other critical issues for plasma facing components include: surface erosion from sputtering and disruption erosion, eddy current forces and runaway electron impact from disruptions, neutron damage, tritium retention and release, remote maintenance of radioactive components, corrosion-erosion, and loss-of-coolant accidents.

  7. Core conditions for alpha heating attained in direct-drive inertial confinement fusion

    DOE PAGES

    Bose, A.; Woo, K. M.; Betti, R.; ...

    2016-07-07

    It is shown that direct-drive implosions on the OMEGA laser have achieved core conditions that would lead to significant alpha heating at incident energies available on the National Ignition Facility (NIF) scale. The extrapolation of the experimental results from OMEGA to NIF energy assumes only that the implosion hydrodynamic efficiency is unchanged at higher energies. This approach is independent of the uncertainties in the physical mechanism that degrade implosions on OMEGA, and relies solely on a volumetric scaling of the experimentally observed core conditions. It is estimated that the current best-performing OMEGA implosion [Regan et al., Phys. Rev. Lett. 117,more » 025001 (2016)] extrapolated to a 1.9 MJ laser driver with the same illumination configuration and laser-target coupling would produce 125 kJ of fusion energy with similar levels of alpha heating observed in current highest performing indirect-drive NIF implosions.« less

  8. Core conditions for alpha heating attained in direct-drive inertial confinement fusion

    SciTech Connect

    Bose, A.; Woo, K. M.; Betti, R.; Campbell, E. M.; Mangino, D.; Christopherson, A. R.; McCrory, R. L.; Nora, R.; Regan, S. P.; Goncharov, V. N.; Sangster, T. C.; Forrest, C. J.; Frenje, J.; Gatu Johnson, M.; Glebov, V. Yu; Knauer, J. P.; Marshall, F. J.; Stoeckl, C.; Theobald, W.

    2016-07-07

    It is shown that direct-drive implosions on the OMEGA laser have achieved core conditions that would lead to significant alpha heating at incident energies available on the National Ignition Facility (NIF) scale. The extrapolation of the experimental results from OMEGA to NIF energy assumes only that the implosion hydrodynamic efficiency is unchanged at higher energies. This approach is independent of the uncertainties in the physical mechanism that degrade implosions on OMEGA, and relies solely on a volumetric scaling of the experimentally observed core conditions. It is estimated that the current best-performing OMEGA implosion [Regan et al., Phys. Rev. Lett. 117, 025001 (2016)] extrapolated to a 1.9 MJ laser driver with the same illumination configuration and laser-target coupling would produce 125 kJ of fusion energy with similar levels of alpha heating observed in current highest performing indirect-drive NIF implosions.

  9. Core conditions for alpha heating attained in direct-drive inertial confinement fusion

    NASA Astrophysics Data System (ADS)

    Bose, A.; Woo, K. M.; Betti, R.; Campbell, E. M.; Mangino, D.; Christopherson, A. R.; McCrory, R. L.; Nora, R.; Regan, S. P.; Goncharov, V. N.; Sangster, T. C.; Forrest, C. J.; Frenje, J.; Gatu Johnson, M.; Glebov, V. Yu; Knauer, J. P.; Marshall, F. J.; Stoeckl, C.; Theobald, W.

    2016-07-01

    It is shown that direct-drive implosions on the OMEGA laser have achieved core conditions that would lead to significant alpha heating at incident energies available on the National Ignition Facility (NIF) scale. The extrapolation of the experimental results from OMEGA to NIF energy assumes only that the implosion hydrodynamic efficiency is unchanged at higher energies. This approach is independent of the uncertainties in the physical mechanism that degrade implosions on OMEGA, and relies solely on a volumetric scaling of the experimentally observed core conditions. It is estimated that the current best-performing OMEGA implosion [Regan et al., Phys. Rev. Lett. 117, 025001 (2016), 10.1103/PhysRevLett.117.025001] extrapolated to a 1.9 MJ laser driver with the same illumination configuration and laser-target coupling would produce 125 kJ of fusion energy with similar levels of alpha heating observed in current highest performing indirect-drive NIF implosions.

  10. Core conditions for alpha heating attained in direct-drive inertial confinement fusion.

    PubMed

    Bose, A; Woo, K M; Betti, R; Campbell, E M; Mangino, D; Christopherson, A R; McCrory, R L; Nora, R; Regan, S P; Goncharov, V N; Sangster, T C; Forrest, C J; Frenje, J; Gatu Johnson, M; Glebov, V Yu; Knauer, J P; Marshall, F J; Stoeckl, C; Theobald, W

    2016-07-01

    It is shown that direct-drive implosions on the OMEGA laser have achieved core conditions that would lead to significant alpha heating at incident energies available on the National Ignition Facility (NIF) scale. The extrapolation of the experimental results from OMEGA to NIF energy assumes only that the implosion hydrodynamic efficiency is unchanged at higher energies. This approach is independent of the uncertainties in the physical mechanism that degrade implosions on OMEGA, and relies solely on a volumetric scaling of the experimentally observed core conditions. It is estimated that the current best-performing OMEGA implosion [Regan et al., Phys. Rev. Lett. 117, 025001 (2016)10.1103/PhysRevLett.117.025001] extrapolated to a 1.9 MJ laser driver with the same illumination configuration and laser-target coupling would produce 125 kJ of fusion energy with similar levels of alpha heating observed in current highest performing indirect-drive NIF implosions.

  11. Fusion production of solid dispersions containing a heat-sensitive active ingredient by hot melt extrusion and Kinetisol dispersing.

    PubMed

    Dinunzio, James C; Brough, Chris; Hughey, Justin R; Miller, Dave A; Williams, Robert O; McGinity, James W

    2010-02-01

    Many techniques for the production of solid dispersions rely on elevated temperatures and prolonged material residence times, which can result in decomposition of temperature-sensitive components. In this study, hydrocortisone was used as a model temperature-sensitive active ingredient to study the effect of formulation and processing techniques as well as to characterize the benefits of KinetiSol Dispersing for the production of solid dispersions. Preformulation studies were conducted using differential scanning calorimetry and hot stage microscopy to identify optimum carriers for the production of amorphous solid dispersions. After identification, solid dispersions were prepared by hot melt extrusion and KinetiSol Dispersing, with material characterized by X-ray diffraction, dissolution and potency testing to evaluate physicochemical properties. Results from the preformulation studies showed that vinylacetate:vinylpyrrolidone (PVPVA) copolymer allowed for hydrocortisone dissolution within the carrier at temperatures as low as 160 degrees C, while hydroxypropyl methylcellulose required temperatures upward of 180 degrees C to facilitate solubilization. Low substituted hydroxypropyl cellulose, a high glass transition temperature control, showed that the material was unable to solubilize hydrocortisone. Manufacturing process control studies using hot melt extruded compositions of hydrocortisone and PVPVA showed that increased temperatures and residence times negatively impacted product potency due to decomposition. Using KinetiSol Dispersing to reduce residence time and to facilitate lower temperature processing, it was possible to produce solid dispersions with improved product potency. This study clearly demonstrated the importance of carrier selection to facilitate lower temperature processing, as well as the effect of residence time on product potency. Furthermore, KinetiSol Dispersing provided significant advantages over hot melt extrusion due to the reduced

  12. EDITORIAL: Safety aspects of fusion power plants

    NASA Astrophysics Data System (ADS)

    Kolbasov, B. N.

    2007-07-01

    neutral beam injectors and the power supply systems were considered. This year the ion cyclotron resonant heating system is under evaluation. I. Cristescu et al (Germany) present the paper `Tritium inventories and tritium safety design principles for the fuel cycle of ITER'. She and her colleagues developed the dynamic mathematical model (TRIMO) for tritium inventory evaluation within each system of the ITER fuel cycle in various operational scenarios. TRIMO is used as a tool for trade-off studies within the fuel cycle systems with the final goal of global tritium inventory minimization. M. Matsuyama et al (Japan) describes a new technique for in situ quantitative measurements of high-level tritium inventory and its distribution in the VV and tritium systems of ITER and future fusion reactors. This technique is based on utilization of x-rays induced by beta-rays emitting from tritium species. It was applied to three physical states of high-level tritium: to gaseous, aqueous and solid tritium retained on/in various materials. Finally, there are four papers devoted to safety issues in fusion reactor decommissioning and waste management. A paper by R. Pampin et al (UK) provides the revised radioactive waste analysis of two models in the PPCS. Another paper by M. Zucchetti (Italy), S.A. Bartenev (Russia) et al describes a radiochemical extraction technology for purification of V-Cr-Ti alloy components from activation products to the dose rate of 10 µSv/h allowing their clearance or hands-on recycling which has been developed and tested in laboratory stationary conditions. L. El-Guebaly (USA) and her colleagues submitted two papers. In the first paper she optimistically considers the possibility of replacing the disposal of fusion power reactor waste with recycling and clearance. Her second paper considers the implications of new clearance guidelines for nuclear applications, particularly for slightly irradiated fusion materials.

  13. Thermal Studies of the Laser Inertial Fusion Energy (LIFE) Target during Injection into the Fusion Chamber

    SciTech Connect

    Miles, R. R.; Havstad, M.; LeBlanc, M.; Chang, A.; Golosker, I.; Rosso, P.

    2014-09-09

    The tests of the external heat transfer coefficient suggests that the values used in the numerical analysis for the temperature distribution within the fusion fuel target following flight into the target chamber are probably valid. The tests of the heat transfer phenomena occurring within the target due the rapid heating of the LEH window for the hot gasses within the fusion chamber show that the heat does indeed convect via the internal helium environment of the target towards the capsule and that the pressure in the front compartment of the target adjacent to the LEH window increases such that t bypass venting of the internal helium into the second chamber adjacent to the capsule is needed to prevent rupture of the membranes. The bypass flow is cooled by the hohlraum during this venting. However, the experiments suggest that our internal heat flow calculations may be low by about a factor of 2. Further studies need to be conducted to investigate the differences between the experiment and the numerical analysis. Future studies could also possibly bring the test conditions closer to those expected in the fusion chamber to better validate the results. A sacrificial layer will probably be required on the LEH window of the target and this can be used to mitigate any unexpected target heating.

  14. Effect of aniseikonia on fusion.

    PubMed

    Sharma, P; Prakash, P

    1991-01-01

    Physiological aniseikonia is the basis of stereopsis but beyond certain limits it becomes an obstacle to fusion. It is not well established as to how much aniseikonia can be tolerated by the fusional mechanism. Different tests under different testing conditions have given a wide range of variation. On the synoptophore we had observed tolerance upto 35% aniseikonia in some cases. Under more physiological conditions on a polaroid dissociation stereoprojector we observed lesser baseline fusional vergences but tolerance in about 70% of the cases upto 30% aniseikonia while 25% could tolerate even 35% aniseikonia. However we realise that these indicate the maximal potential and not the symptom free tolerable limits.

  15. Osmotic control of bilayer fusion.

    PubMed Central

    Fisher, L R; Parker, N S

    1984-01-01

    We have used photography and capacitance measurement to monitor the steps in the interaction and eventual fusion of optically black lipid bilayers (BLMs), hydrostatically bulged to approximately hemispherical shape and pushed together mechanically. A necessary first step is drainage of aqueous solution from between the bilayers to allow close contact of the bilayers. The drainage can be controlled by varying the osmotic difference across the bilayers. If the differences are such as to remove water from between the bilayers, fusion occurs after a time that depends on the net osmotic difference and the area of contact. If there is an osmotic flow of water into the space between the bilayers, fusion never occurs. In the fusion process, a single central bilayer forms from the original apposed pair of bilayers. The central bilayer may later burst to allow mixing of the two volumes originally bounded by the separate bilayer; the topological equivalent of exocytosis. Images FIGURE 2 PMID:6541065

  16. Control of mechanically activated polymersome fusion: Factors affecting fusion

    DOE PAGES

    Henderson, Ian M.; Paxton, Walter F.

    2014-12-15

    Previously we have studied the mechanically-activated fusion of extruded (200 nm) polymer vesicles into giant polymersomes using agitation in the presence of salt. In this study we have investigated several factors contributing to this phenomenon, including the effects of (i) polymer vesicle concentration, (ii) agitation speed and duration, and iii) variation of the salt and its concentration. It was found that increasing the concentration of the polymer dramatically increases the production of giant vesicles through the increased collisions of polymersomes. Our investigations also found that increasing the frequency of agitation increased the efficiency of fusion, though ultimately limited the sizemore » of vesicle which could be produced due to the high shear involved. Finally it was determined that salt-mediation of the fusion process was not limited to NaCl, but is instead a general effect facilitated by the presence of solvated ionic compounds, albeit with different salts initiating fusion at different concentration.« less

  17. Control of mechanically activated polymersome fusion: Factors affecting fusion

    SciTech Connect

    Henderson, Ian M.; Paxton, Walter F.

    2014-12-15

    Previously we have studied the mechanically-activated fusion of extruded (200 nm) polymer vesicles into giant polymersomes using agitation in the presence of salt. In this study we have investigated several factors contributing to this phenomenon, including the effects of (i) polymer vesicle concentration, (ii) agitation speed and duration, and iii) variation of the salt and its concentration. It was found that increasing the concentration of the polymer dramatically increases the production of giant vesicles through the increased collisions of polymersomes. Our investigations also found that increasing the frequency of agitation increased the efficiency of fusion, though ultimately limited the size of vesicle which could be produced due to the high shear involved. Finally it was determined that salt-mediation of the fusion process was not limited to NaCl, but is instead a general effect facilitated by the presence of solvated ionic compounds, albeit with different salts initiating fusion at different concentration.

  18. A novel hNIS/tdTomato fusion reporter for visualizing the relationship between the cellular localization of sodium iodide symporter and its iodine uptake function under heat shock treatment.

    PubMed

    Yeom, Chan Joo; Chung, Taemoon; Youn, Hyewon; Kang, Keon Wook; Lee, Dong Soo; Chung, June-Key

    2015-01-01

    The function of membrane-localized sodium iodide symporter (NIS) determines the efficacy of radioiodine therapy in thyroid cancer. Here, we describe a dual mode reporter fused with human NIS (hNIS) and a red fluorescent protein named tandem dimeric Tomato (tdTomato) for the in vitro and in vivo imaging of hNIS protein expression, localization, and iodide uptake function. Human cervical epithelial adenocarcinoma cell line (HeLa)-hNIS/tdTomato cells were established by transducing a fusion gene expressing hNIS/tdTomato under the control of a cytomegalovirus promoter. Fluorescence imaging, confocal microscopy, and an 125I uptake assay were performed to validate the integrity of the fusion protein. Actinomycin D and cycloheximide were used to block newly synthesized hNIS proteins. In vivo images were acquired using a gamma camera and a Maestro fluorescence imaging device. The fluorescence intensity of membrane-localized hNIS and 125I uptake both were increased after heat shock. Scintigraphy and fluorescence imaging indicated specific accumulation of the hNIS/tdTomato fusion protein in xenografted tumors, supporting the utility of this system for in vivo monitoring of hNIS expression and activity. We developed a novel hNIS/tdTomato dual mode reporter that enables visualization of the expression, localization, and iodine uptake function of hNIS in vitro and in vivo.

  19. Technological requisites of the magnetic fusion energy programme

    SciTech Connect

    Cooper, W.A.

    1983-01-01

    An integral part of magnetic fusion energy research is the development of the technologies necessary for the confinement and heating of reactor-level plasmas. Heating systems based on energetic neutral beam particle injection or radio frequency waves (or both) will be required to heat plasmas to the temperatures at which fusion is self-sustaining. These systems may be used also to drive plasma currents. The magnet systems required to confine reactor-sized plasmas rely on the development of effective superconductors. Issues associated with safety and tritium handling concerns become important considerations in designing reactor concepts.

  20. Task toward a Realization of Commercial Tokamak Fusion Plants in 2050 -The Role of ITER and the Succeeding Developments- 3.Fusion Plasma Research toward Fusion Power Plants

    NASA Astrophysics Data System (ADS)

    Kamada, Yutaka; Shimada, Michiya; Miura, Yukitoshi; Ogawa, Yuichi

    This section discusses fusion plasma research that needs to be carried out to develop fusion power plants. Burning plasma, in which self-heating by energetic alph aparticles plays an essential role, should be recognized as autonomous system. This is quite different from present plasma experiments, suggesting a possibility to yield some qualitative changes in fusion plasma research. Research with ITER is strongly expected to contribute to this burning plasma physics. In addition, plasma performance in steady-state and at high beta is very important in fusion power plants from the engineering and economical viewpoints. Plasma parameters expected for fusion power plants are discussed, and present status of experimental research is reviewed. Research in devices other than ITER with unique features would be instrumental for exploring high performance plasmas. A necessity of research complementary to ITER plasma is discussed.

  1. Nuclear Propulsion through Direct Conversion of Fusion Energy: The Fusion Driven Rocket

    NASA Technical Reports Server (NTRS)

    Slough, John; Pancotti, Anthony; Kirtley, David; Pihl, Christopher; Pfaff, Michael

    2012-01-01

    The future of manned space exploration and development of space depends critically on the creation of a dramatically more proficient propulsion architecture for in-space transportation. A very persuasive reason for investigating the applicability of nuclear power in rockets is the vast energy density gain of nuclear fuel when compared to chemical combustion energy. Current nuclear fusion efforts have focused on the generation of electric grid power and are wholly inappropriate for space transportation as the application of a reactor based fusion-electric system creates a colossal mass and heat rejection problem for space application.

  2. A review of pulse fusion propulsion

    NASA Astrophysics Data System (ADS)

    Cassenti, Brice N.

    2002-01-01

    During the last forty years there has been considerable interest in both internal and external pulse propulsion systems. Over this time the nuclear devices being considered have grown considerably smaller than those initially examined. Now pellets are normally in the range from 15 cm down to 2 cm in diameter, and fusion devices are generally preferred. High energy density triggers (such as lasers, particle beams or antiprotons) have been considered for detonating the fusion fuel. When antiprotons are considered it is more efficient to annihilate the antiprotons in a fissionable material, and then use the energy from the fission reaction to drive the fusion reaction in the pellet, than to use the annihilation energy directly. Finally, fissionable material can be used to boost the performance of a fusion system. The early concepts, which used critical mass devices, do not satisfy the ban on nuclear weapons in space, and are only rarely considered today. Concepts based on inertial confinement fusion are heavier than those that use antiprotons for the trigger since the mass associated with the lasers, or particle beams and their power supplies are considerably heavier than the traps used for antiprotons. Hence, from a performance, and even a political, point of view the antiproton-triggered approach is the most desirable, but it also requires more development. Not only is the trigger lighter but an external pulse propulsion rocket does not necessarily need radiators to reject excess heat and, hence, can be even lighter. Propulsion systems based on critical mass devices are clearly feasible, so the primary problem is to reduce the size of the explosive devices so that a critical mass is not required. If pulse nuclear fusion propulsion can become a reality then the performance is enough to complete manned missions to the inner planets in weeks and the outer planets in months. .

  3. The Parameter Space of Magnetized Target Fusion (aka Magneto-Inertial Fusion)

    NASA Astrophysics Data System (ADS)

    Lindemuth, Irvin

    2016-10-01

    Magnetized Target Fusion (MTF), aka Magneto-Inertial Fusion (MIF), is an approach to fusion that compresses a preformed, magnetized (but not necessarily magnetically confined) plasma with an imploding liner or pusher. MTF/MIF operates in a density regime in between the eleven orders of magnitude (1011) in density that separate inertial confinement fusion (ICF) from magnetic confinement fusion MCF. Compared to MCF, the higher density, shorter confinement times, and compressional heating as the dominant heating mechanism potentially reduce the impact of magnetic instabilities. Compared to ICF, the magnetically reduced thermal transport and lower density leads to orders-of-magnitude reduction in the difficult-to-achieve areal-density parameter and a significant reduction in required implosion velocity and radial convergence, potentially reducing the deleterious effects of implosion hydrodynamic instabilities. This tutorial presents fundamental analysis and simple time-dependent modeling to show where significant fusion gain might be achieved in the intermediate-density regime. The analysis shows that the fusion design space is potentially a continuum between ICF and MCF but practical considerations limit the space in which ignition might be obtained. Generic time-dependent modeling addresses the key physics requirements and defines ``ball-park'' values needed for target-plasma initial density, temperature, and magnetic field and implosion system size, energy, and velocity. The modeling shows energy gains greater than 30 can potentially be achieved and that high gain may be obtained at low convergence ratios, e.g., less than 15. A non-exhaustive review of past and present MTF/MIF efforts is presented and the renewed interest in MTF/MIF within the US (e.g., ARPA-E's ALPHA program) and abroad is noted.

  4. Vacuum fusion bonding of glass plates

    DOEpatents

    Swierkowski, Steve P.; Davidson, James C.; Balch, Joseph W.

    2000-01-01

    An improved apparatus and method for vacuum fusion bonding of large, patterned glass plates. One or both glass plates are patterned with etched features such as microstructure capillaries and a vacuum pumpout moat, with one plate having at least one hole therethrough for communication with a vacuum pumpout fixture. High accuracy alignment of the plates is accomplished by a temporary clamping fixture until the start of the fusion bonding heat cycle. A complete, void-free fusion bond of seamless, full-strength quality is obtained through the plates; because the glass is heated well into its softening point and because of a large, distributed force that is developed that presses the two plates together from the difference in pressure between the furnace ambient (high pressure) and the channeling and microstructures in the plates (low pressure) due to the vacuum drawn. The apparatus and method may be used to fabricate microcapillary arrays for chemical electrophoresis; for example, any apparatus using a network of microfluidic channels embedded between plates of glass or similar moderate melting point substrates with a gradual softening point curve, or for assembly of glass-based substrates onto larger substrates, such as in flat panel display systems.

  5. Vacuum fusion bonding of glass plates

    DOEpatents

    Swierkowski, Steve P.; Davidson, James C.; Balch, Joseph W.

    2001-01-01

    An improved apparatus and method for vacuum fusion bonding of large, patterned glass plates. One or both glass plates are patterned with etched features such as microstructure capillaries and a vacuum pumpout moat, with one plate having at least one hole therethrough for communication with a vacuum pumpout fixture. High accuracy alignment of the plates is accomplished by a temporary clamping fixture until the start of the fusion bonding heat cycle. A complete, void-free fusion bond of seamless, full-strength quality is obtained through the plates; because the glass is heated well into its softening point and because of a large, distributed force that is developed that presses the two plates together from the difference in pressure between the furnace ambient (high pressure) and the channeling and microstructures in the plates (low pressure) due to the vacuum drawn. The apparatus and method may be used to fabricate microcapillary arrays for chemical electrophoresis; for example, any apparatus using a network of microfluidic channels embedded between plates of glass or similar moderate melting point substrates with a gradual softening point curve, or for assembly of glass-based substrates onto larger substrates, such as in flat panel display systems.

  6. Review of methods for fusion bonding thermoplastic composites

    SciTech Connect

    Benatar, A.; Gutowski, T.G.

    1987-02-01

    Bonding of thermoplastic composites is a critical step in the manufacture of aerospace structures. The objective of this project is to investigate different methods for fusion bonding thermoplastic composites quickly, with a good bond strength, and without warping and deconsolidation. This is best accomplished by heating and melting the thermoplastic on the bond surface only, and then pressing the parts together for a fusion bond. For this purpose, a variety of surface heating techniques were examined for bonding of PEEK and J Polymer composites. These included: resistance heating, infrared heating, induction heating, dielectric/microwave heating, and ultrasonic welding. In resistance heating, a single prepreg ply was placed between the composites and heated by passing electric current through the graphite fibers. With induction heating, a single ply of nickel coated graphite fibers was placed between the composites and heated. Ultrasonic welding was done by molding thermoplastic-only energy directors into the composites; the ultrasonic vibration melted these energy directors thereby fusion bonding the parts. 20 references.

  7. Charge-exchange and fusion reaction measurements during compression experiments with neutral beam heating in the Tokamak Fusion Test Reactor

    SciTech Connect

    Kaita, R.; Heidbrink, W.W.; Hammett, G.W.; Chan, A.A.; England, A.C.; Hendel, H.W.; Medley, S.S.; Nieschmidt, E.; Roquemore, A.L.; Scott, S.D.

    1986-04-01

    Adiabatic toroidal compression experiments were performed in conjunction with high power neutral beam injection in the Tokamak Fusion Test Reactor (TFTR). Acceleration of beam ions to energies nearly twice the injection energy was measured with a charge-exchange neutral particle analyzer. Measurements were also made of 2.5 MeV neutrons and 15 MeV protons produced in fusion reactions between the deuterium beam ions and the thermal deuterium and /sup 3/He ions, respectively. When the plasma was compressed, the d(d,n)/sup 3/He fusion reaction rate increased a factor of five, and the /sup 3/He(d,p)/sup 4/He rate by a factor of twenty. These data were simulated with a bounce-averaged Fokker-Planck program, which assumed conservation of angular momentum and magnetic moment during compression. The results indicate that the beam ion acceleration was consistent with adiabatic scaling.

  8. The emissivities of liquid metals at their fusion temperatures

    NASA Technical Reports Server (NTRS)

    Bonnell, D. W.; Treverton, J. A.; Valerga, A. J.; Margrave, J. L.

    1972-01-01

    A survey of the literature through 1969 shows an almost total lack of experimental emissivity data for metals in the liquid state. The emissivities for several transition metals and various other metals and compounds in the liquid state at their fusion temperatures have been determined. The technique used involves electromagnetic levitation-induction heating of the materials in an inert atmosphere. The brightness temperature of the liquid phase of the material is measured as the material is heated through fusion. Given a reliable value of the fusion temperature, which is available for most pure substances, one may readily calculate an emissivity for the liquid phase at the fusion temperatures. Even in cases where melting points are poorly known, the brightness temperatures are unique parameters, independent of the temperature scale and measured for a chemically defined system at a fixed point. Better emissivities may be recalculated as better melting point data become available.

  9. Characterization of fusion genes and the significantly expressed fusion isoforms in breast cancer by hybrid sequencing.

    PubMed

    Weirather, Jason L; Afshar, Pegah Tootoonchi; Clark, Tyson A; Tseng, Elizabeth; Powers, Linda S; Underwood, Jason G; Zabner, Joseph; Korlach, Jonas; Wong, Wing Hung; Au, Kin Fai

    2015-10-15

    We developed an innovative hybrid sequencing approach, IDP-fusion, to detect fusion genes, determine fusion sites and identify and quantify fusion isoforms. IDP-fusion is the first method to study gene fusion events by integrating Third Generation Sequencing long reads and Second Generation Sequencing short reads. We applied IDP-fusion to PacBio data and Illumina data from the MCF-7 breast cancer cells. Compared with the existing tools, IDP-fusion detects fusion genes at higher precision and a very low false positive rate. The results show that IDP-fusion will be useful for unraveling the complexity of multiple fusion splices and fusion isoforms within tumorigenesis-relevant fusion genes.

  10. Rapid heating of matter using high power lasers

    SciTech Connect

    Bang, Woosuk

    2016-04-08

    This slide presentation describes motivation (uniform and rapid heating of a target, opportunity to study warm dense matter, study of nuclear fusion reactions), rapid heating of matter with intense laser-driven ion beams, visualization of the expanding warm dense gold and diamond, and nuclear fusion experiments using high power lasers (direct heating of deuterium spheres (radius ~ 10nm) with an intense laser pulse.

  11. Accelerator and Fusion Research Division: summary of activities, 1983

    SciTech Connect

    Not Available

    1984-08-01

    The activities described in this summary of the Accelerator and Fusion Research Division are diverse, yet united by a common theme: it is our purpose to explore technologically advanced techniques for the production, acceleration, or transport of high-energy beams. These beams may be the heavy ions of interest in nuclear science, medical research, and heavy-ion inertial-confinement fusion; they may be beams of deuterium and hydrogen atoms, used to heat and confine plasmas in magnetic fusion experiments; they may be ultrahigh-energy protons for the next high-energy hadron collider; or they may be high-brilliance, highly coherent, picosecond pulses of synchrotron radiation.

  12. Ultrastructural Analysis of Myoblast Fusion in Drosophila

    PubMed Central

    Zhang, Shiliang; Chen, Elizabeth H.

    2015-01-01

    Summary Myoblast fusion in Drosophila has become a powerful genetic system with which to unravel the mechanisms underlying cell fusion. The identification of important components of myoblast fusion by genetic analysis has led to a molecular pathway toward our understanding of this cellular process. In addition to the application of immunohistochemistry and live imaging techniques to visualize myoblast fusion at the light microscopic level, ultrastructural analysis using electron microscopy remains an indispensable tool to reveal fusion intermediates and specific membrane events at sites of fusion. In this chapter, we describe conventional chemical fixation and high-pressure freezing/freeze substitution methods for visualizing fusion intermediates during Drosophila myoblast fusion. Furthermore, we describe an immunoelectron microscopic method for localizing specific proteins relative to the fusion apparatus. PMID:18979250

  13. Rapid heating of matter using high power lasers

    SciTech Connect

    Bang, Woosuk

    2015-11-05

    This report describes rapid heating technology with ion sources. LANL calculated the expected heating per atom and temperatures of the target materials, used alumium ion beams to heat gold and diamond, produced deuterium fusion plasmas and then measured the ion temperature at the time of the fusion reactions.

  14. Cold fusion research

    SciTech Connect

    1989-11-01

    I am pleased to forward to you the Final Report of the Cold Fusion Panel. This report reviews the current status of cold fusion and includes major chapters on Calorimetry and Excess Heat, Fusion Products and Materials Characterization. In addition, the report makes a number of conclusions and recommendations, as requested by the Secretary of Energy.

  15. Magnetic flux and heat losses by diffusive, advective, and Nernst effects in magnetized liner inertial fusion-like plasma

    SciTech Connect

    Velikovich, A. L.; Giuliani, J. L.; Zalesak, S. T.

    2015-04-15

    The magnetized liner inertial fusion (MagLIF) approach to inertial confinement fusion [Slutz et al., Phys. Plasmas 17, 056303 (2010); Cuneo et al., IEEE Trans. Plasma Sci. 40, 3222 (2012)] involves subsonic/isobaric compression and heating of a deuterium-tritium plasma with frozen-in magnetic flux by a heavy cylindrical liner. The losses of heat and magnetic flux from the plasma to the liner are thereby determined by plasma advection and gradient-driven transport processes, such as thermal conductivity, magnetic field diffusion, and thermomagnetic effects. Theoretical analysis based on obtaining exact self-similar solutions of the classical collisional Braginskii's plasma transport equations in one dimension demonstrates that the heat loss from the hot compressed magnetized plasma to the cold liner is dominated by transverse heat conduction and advection, and the corresponding loss of magnetic flux is dominated by advection and the Nernst effect. For a large electron Hall parameter (ω{sub e}τ{sub e}≫1), the effective diffusion coefficients determining the losses of heat and magnetic flux to the liner wall are both shown to decrease with ω{sub e}τ{sub e} as does the Bohm diffusion coefficient cT/(16eB), which is commonly associated with low collisionality and two-dimensional transport. We demonstrate how this family of exact solutions can be used for verification of codes that model the MagLIF plasma dynamics.

  16. Magnetic flux and heat losses by diffusive, advective, and Nernst effects in magnetized liner inertial fusion-like plasma

    NASA Astrophysics Data System (ADS)

    Velikovich, A. L.; Giuliani, J. L.; Zalesak, S. T.

    2015-04-01

    The magnetized liner inertial fusion (MagLIF) approach to inertial confinement fusion [Slutz et al., Phys. Plasmas 17, 056303 (2010); Cuneo et al., IEEE Trans. Plasma Sci. 40, 3222 (2012)] involves subsonic/isobaric compression and heating of a deuterium-tritium plasma with frozen-in magnetic flux by a heavy cylindrical liner. The losses of heat and magnetic flux from the plasma to the liner are thereby determined by plasma advection and gradient-driven transport processes, such as thermal conductivity, magnetic field diffusion, and thermomagnetic effects. Theoretical analysis based on obtaining exact self-similar solutions of the classical collisional Braginskii's plasma transport equations in one dimension demonstrates that the heat loss from the hot compressed magnetized plasma to the cold liner is dominated by transverse heat conduction and advection, and the corresponding loss of magnetic flux is dominated by advection and the Nernst effect. For a large electron Hall parameter ( ωeτe≫1 ), the effective diffusion coefficients determining the losses of heat and magnetic flux to the liner wall are both shown to decrease with ωeτe as does the Bohm diffusion coefficient c T /(16 e B ) , which is commonly associated with low collisionality and two-dimensional transport. We demonstrate how this family of exact solutions can be used for verification of codes that model the MagLIF plasma dynamics.

  17. Successful anterior fusion following posterior cervical fusion for revision of anterior cervical discectomy and fusion pseudarthrosis.

    PubMed

    Elder, Benjamin D; Sankey, Eric W; Theodros, Debebe; Bydon, Mohamad; Goodwin, C Rory; Lo, Sheng-Fu; Kosztowski, Thomas A; Belzberg, Allen J; Wolinsky, Jean-Paul; Sciubba, Daniel M; Gokaslan, Ziya L; Bydon, Ali; Witham, Timothy F

    2016-02-01

    Pseudarthrosis occurs after approximately 2-20% of anterior cervical discectomy and fusion (ACDF) procedures; it is unclear if posterior or anterior revision should be pursued. In this study, we retrospectively evaluate the outcomes in 22 patients with pseudarthrosis following ACDF and revision via posterior cervical fusion (PCF). Baseline demographics, preoperative symptoms, operative data, time to fusion failure, symptoms of pseudarthrosis, and revision method were assessed. Fusion outcome and clinical outcome were determined at last follow-up (LFU). Thirteen females (59%) and 9 (41%) males experienced pseudarthrosis at a median of 11 (range: 3-151)months after ACDF. Median age at index surgery was 51 (range: 33-67)years. All patients with pseudarthrosis presented with progressive neck pain, with median visual analog scale (VAS) score of 8 (range: 0-10), and/or myeloradiculopathy. Patients with pseudarthrosis <12 months compared to >12 months after index surgery were older (p=0.013), had more frequent preoperative neurological deficits (p=0.064), and lower baseline VAS scores (p=0.006). Fusion was successful after PCF in all patients, with median time to fusion of 10 (range: 2-14)months. Eighteen patients fused both anteriorly and posteriorly, two patients fused anteriorly only, and two patients fused posteriorly only. Median VAS neck score at LFU significantly improved from the time of pseudarthrosis (p=0.012). While uncommon, pseudarthrosis may occur after ACDF. All patients achieved successful fusion after subsequent posterior cervical fusion, with 91% fusing a previous anterior pseudarthrosis after posterior stabilization. Neck pain significantly improved by LFU in the majority of patients in this study.

  18. Acidification triggers Andes hantavirus membrane fusion and rearrangement of Gc into a stable post-fusion homotrimer.

    PubMed

    Acuña, Rodrigo; Bignon, Eduardo A; Mancini, Roberta; Lozach, Pierre-Yves; Tischler, Nicole D

    2015-11-01

    The hantavirus membrane fusion process is mediated by the Gc envelope glycoprotein from within endosomes. However, little is known about the specific mechanism that triggers Gc fusion activation, and its pre- and post-fusion conformations. We established cell-free in vitro systems to characterize hantavirus fusion activation. Low pH was sufficient to trigger the interaction of virus-like particles with liposomes. This interaction was dependent on a pre-fusion glycoprotein arrangement. Further, low pH induced Gc multimerization changes leading to non-reversible Gc homotrimers. These trimers were resistant to detergent, heat and protease digestion, suggesting characteristics of a stable post-fusion structure. No acid-dependent oligomerization rearrangement was detected for the trypsin-sensitive Gn envelope glycoprotein. Finally, acidification induced fusion of glycoprotein-expressing effector cells with non-susceptible CHO cells. Together, the data provide novel information on the Gc fusion trigger and its non-reversible activation involving lipid interaction, multimerization changes and membrane fusion which ultimately allow hantavirus entry into cells.

  19. Evaluation of helium cooling for fusion divertors

    SciTech Connect

    Baxi, C.B.

    1993-09-01

    The divertors of future fusion reactors will have a power throughput of several hundred MW. The peak heat flux on the diverter surface is estimated to be 5 to 15 MW/m{sup 2} at an average heat flux of 2 MW/m{sup 2}. The divertors have a requirement of both minimum temperature (100{degrees}C) and maximum temperature. The minimum temperature is dictated by the requirement to reduce the absorption of plasma, and the maximum temperature is determined by the thermo-mechanical properties of the plasma facing materials. Coolants that have been considered for fusion reactors are water, liquid metals and helium. Helium cooling has been shown to be very attractive from safety and other considerations. Helium is chemically and neutronically inert and is suitable for power conversion. The challenges associated with helium cooling are: (1) Manifold sizes; (2) Pumping power; and (3) Leak prevention. In this paper the first two of the above design issues are addressed. A variety of heat transfer enhancement techniques are considered to demonstrate that the manifold sizes and the pumping power can be reduced to acceptable levels. A helium-cooled diverter module was designed and fabricated by GA for steady-state heat flux of 10 MW/m{sup 2}. This module was recently tested at Sandia National Laboratories. At an inlet pressure of 4 MPa, the module was tested at a steady-state heat flux of 10 MW/m{sup 2}. The pumping power required was less than 1% of the power removed. These results verified the design prediction.

  20. Magnetic fusion energy plasma interactive and high heat flux components. Volume I. Technical assessment of the critical issues and problem areas in the plasma materials interaction field

    SciTech Connect

    Conn, R.W.; Gauster, W.B.; Heifetz, D.; Marmar, E.; Wilson, K.L.

    1984-01-01

    A technical assessment of the critical issues and problem areas in the field of plasma materials interactions (PMI) in magnetic fusion devices shows these problems to be central for near-term experiments, for intermediate-range reactor devices including D-T burning physics experiments, and for long-term reactor machines. Critical technical issues are ones central to understanding and successful operation of existing and near-term experiments/reactors or devices of great importance for the long run, i.e., ones which will require an extensive, long-term development effort and thus should receive attention now. Four subgroups were formed to assess the critical PMI issues along four major lines: (1) PMI and plasma confinement physics experiments; (2) plasma-edge modelling and theory; (3) surface physics; and (4) materials technology for in-vessel components and the first wall. The report which follows is divided into four major sections, one for each of these topics.

  1. A Summary of the NASA Fusion Propulsion Workshop 2000

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Turchi, Peter J.; Santarius, John F.; Schafer, Charles (Technical Monitor)

    2001-01-01

    A NASA Fusion Propulsion Workshop was held on Nov. 8 and 9, 2000 at Marshall Space Flight Center (MSFC) in Huntsville, Alabama. A total of 43 papers were presented at the Workshop orally or by posters, covering a broad spectrum of issues related to applying fusion to propulsion. The status of fusion research was reported at the Workshop showing the outstanding scientific research that has been accomplished worldwide in the fusion energy research program. The international fusion research community has demonstrated the scientific principles of fusion creating plasmas with conditions for fusion burn with a gain of order unity: 0.25 in Princeton TFTR, 0.65 in the Joint European Torus, and a Q-equivalent of 1.25 in Japan's JT-60. This research has developed an impressive range of physics and technological capabilities that may be applied effectively to the research of possibly new propulsion-oriented fusion schemes. The pertinent physics capabilities include the plasma computational tools, the experimental plasma facilities, the diagnostics techniques, and the theoretical understanding. The enabling technologies include the various plasma heating, acceleration, and the pulsed power technologies.

  2. Chamber transport of ''foot'' pulses for heavy-ion fusion

    SciTech Connect

    Sharp, W.M.; Callahan-Miller, D.A.; Tabak, M.; Yu, S.S.; Peterson, P.F.

    2002-02-20

    Indirect-drive targets for heavy-ion fusion must initially be heated by ''foot'' pulses that precede the main heating pulses by tens of nanoseconds. These pulses typically have a lower energy and perveance than the main pulses, and the fusion-chamber environment is different from that seen by later pulses. The preliminary particle-in-cell simulations of foot pulses here examine the sensitivity of the beam focusing to ion-beam perveance, background-gas density, and pre-neutralization by a plasma near the chamber entry port.

  3. Evaluation of performance of select fusion experiments and projected reactors

    NASA Technical Reports Server (NTRS)

    Miley, G. H.

    1978-01-01

    The performance of NASA Lewis fusion experiments (SUMMA and Bumpy Torus) is compared with other experiments and that necessary for a power reactor. Key parameters cited are gain (fusion power/input power) and the time average fusion power, both of which may be more significant for real fusion reactors than the commonly used Lawson parameter. The NASA devices are over 10 orders of magnitude below the required powerplant values in both gain and time average power. The best experiments elsewhere are also as much as 4 to 5 orders of magnitude low. However, the NASA experiments compare favorably with other alternate approaches that have received less funding than the mainline experiments. The steady-state character and efficiency of plasma heating are strong advantages of the NASA approach. The problem, though, is to move ahead to experiments of sufficient size to advance in gain and average power parameters.

  4. Overview of US heavy ion fusion research

    SciTech Connect

    Logan, B.G.; Bieniosek, F.M.; Celata, C.M.; Henestroza, E.; Kwan,J.W.; Lee, E.P.; Leitner, M.; Roy, P.K.; Seidl, P.A.; Eylon, S.; Vay,J-L.; Waldron, W.L.; Yu, S.S.; Barnard, J.J.; Callahan, D.A.; Cohen,R.H.; Friedman, A.; Grote, D.P; Covo, Kireeff M.; Meier, W.R.; Molvik,A.W.; Lund, S.M.; Davidson, R.C.; Efthimion, P.C.; Gilson, E.P.; Grisham,L.R.; Kaganovich, I.D.; Qin, H.; Startsev, E.A.; Rose, D.V.; Welch, D.R.; Olson, C.L.; Kishek, R.A.; O'Shea, P.; Haber, I.; Prost, L.R.; Prost, L.

    2004-11-01

    Significant experimental and theoretical progress has been made in the U.S. heavy ion fusion program on high-current sources, injectors, transport, final focusing, chambers and targets for high energy density physics (HEDP) and inertial fusion energy (IFE) driven by induction linac accelerators. One focus of present research is the beam physics associated with quadrupole focusing of intense, space-charge dominated heavy-ion beams, including gas and electron cloud effects at high currents, and the study of long-distance-propagation effects such as emittance growth due to field errors in scaled experiments. A second area of emphasis in present research is the introduction of background plasma to neutralize the space charge of intense heavy ion beams and assist in focusing the beams to a small spot size. In the near future, research will continue in the above areas, and a new area of emphasis will be to explore the physics of neutralized beam compression and focusing to high intensities required to heat targets to high energy density conditions as well as for inertial fusion energy.

  5. Overview of US heavy ion fusion research

    SciTech Connect

    Logan, B.G.; Bieniosek, F.M.; Celata, C.M.; Henestroza, E.; Kwan,J.W.; Lee, E.P.; Leitner, M.; Roy, P.K.; Seidl, P.A.; Eylon, S.; Vay,J-L.; Waldron, W.L.; Yu, S.S.; Barnard, J.J.; Callahan, D.A.; Cohen,R.H.; Friedman, A.; Grote, D.P.; Kireeff Covo, M.; Meier, W.R.; Molvik,A.W.; Lund, S.M.; Davidson, R.C.; Efthimion, P.C.; Gilson, E.P.; Grisham,L.R.; Kaganovich, I.D.; Qin, H.; Startsev, E.A.; Rose, D.V.; Welch, D.R.; Olson, C.L.; Kishek, R.A.; O'Shea, P.; Haber, I.; Prost, L.R.

    2005-06-23

    Significant experimental and theoretical progress has been made in the U.S. heavy ion fusion program on high-current sources, injectors, transport, final focusing, chambers and targets for high energy density physics (HEDP) and inertial fusion energy (IFE) driven by induction linac accelerators. One focus of present research is the beam physics associated with quadrupole focusing of intense, space-charge dominated heavy-ion beams, including gas and electron cloud effects at high currents, and the study of long-distance-propagation effects such as emittance growth due to field errors in scaled experiments. A second area of emphasis in present research is the introduction of background plasma to neutralize the space charge of intense heavy ion beams and assist in focusing the beams to a small spot size. In the near future, research will continue in the above areas, and a new area of emphasis will be to explore the physics of neutralized beam compression and focusing to high intensities required to heat targets to high energy density conditions as well as for inertial fusion energy.

  6. Mechanisms of influenza viral membrane fusion.

    PubMed

    Blijleven, Jelle S; Boonstra, Sander; Onck, Patrick R; van der Giessen, Erik; van Oijen, Antoine M

    2016-12-01

    Influenza viral particles are enveloped by a lipid bilayer. A major step in infection is fusion of the viral and host cellular membranes, a process with large kinetic barriers. Influenza membrane fusion is catalyzed by hemagglutinin (HA), a class I viral fusion protein activated by low pH. The exact nature of the HA conformational changes that deliver the energy required for fusion remains poorly understood. This review summarizes our current knowledge of HA structure and dynamics, describes recent single-particle experiments and modeling studies, and discusses their role in understanding how multiple HAs mediate fusion. These approaches provide a mechanistic picture in which HAs independently and stochastically insert into the target membrane, forming a cluster of HAs that is collectively able to overcome the barrier to membrane fusion. The new experimental and modeling approaches described in this review hold promise for a more complete understanding of other viral fusion systems and the protein systems responsible for cellular fusion.

  7. High-power microwave transmission and launching systems for fusion plasma heating systems

    SciTech Connect

    Bigelow, T.S.

    1989-01-01

    Microwave power in the 30- to 300-GHz frequency range is becoming widely used for heating of plasma in present-day fusion energy magnetic confinement experiments. Microwave power is effective in ionizing plasma and heating electrons through the electron cyclotron heating (ECH) process. Since the power is absorbed in regions of the magnetic field where resonance occurs and launching antennas with narrow beam widths are possible, power deposition location can be highly controlled. This is important for maximizing the power utilization efficiency and improving plasma parameters. Development of the gyrotron oscillator tube has advanced in recent years so that a 1-MW continuous-wave, 140-GHz power source will soon be available. Gyrotron output power is typically in a circular waveguide propagating a circular electric mode (such as TE/sub 0,2/) or a whispering-gallery mode (such as TE/sub 15,2/), depending on frequency and power level. An alternative high-power microwave source currently under development is the free-electron laser (FEL), which may be capable of generating 2-10 MW of average power at frequencies of up to 500 GHz. The FEL has a rectangular output waveguide carrying the TE/sub 0,1/ mode. Because of its higher complexity and cost, the high-average-power FEL is not yet as extensively developed as the gyrotron. In this paper, several types of operating ECH transmission systems are discussed, as well systems currently being developed. The trend in this area is toward higher power and frequency due to the improvements in plasma density and temperature possible. Every system requires a variety of components, such as mode converters, waveguide bends, launchers, and directional couplers. Some of these components are discussed here, along with ongoing work to improve their performance. 8 refs.

  8. Equivalence of measurement space solution data fusion and complete fusion

    NASA Astrophysics Data System (ADS)

    Ceccherini, Simone

    2016-10-01

    Many observation systems are operating on space-borne and airborne platforms, as well as from ground-based stations, providing measurements of vertical profiles of atmospheric parameters. When independent measurements of the same profile are available data fusion methods can be used to combine them and exploit all the available information for a more comprehensive and accurate description of the atmospheric state. Several data fusion methods can be used. Among the others, both the measurement space solution data fusion method and the complete fusion method have the remarkable properties of using all the acquired information and of providing results that are independent from a priori information used in the individual retrievals. For this reason, though the two methods use two completely different procedures, it is reasonable to expect that they give the same results and in this paper the rigorous proof of the equivalence of the two methods is given. Therefore, the choice between them is only driven by the advantages of the different implementations.

  9. A review of data fusion techniques.

    PubMed

    Castanedo, Federico

    2013-01-01

    The integration of data and knowledge from several sources is known as data fusion. This paper summarizes the state of the data fusion field and describes the most relevant studies. We first enumerate and explain different classification schemes for data fusion. Then, the most common algorithms are reviewed. These methods and algorithms are presented using three different categories: (i) data association, (ii) state estimation, and (iii) decision fusion.

  10. A Review of Data Fusion Techniques

    PubMed Central

    2013-01-01

    The integration of data and knowledge from several sources is known as data fusion. This paper summarizes the state of the data fusion field and describes the most relevant studies. We first enumerate and explain different classification schemes for data fusion. Then, the most common algorithms are reviewed. These methods and algorithms are presented using three different categories: (i) data association, (ii) state estimation, and (iii) decision fusion. PMID:24288502

  11. Inspection of Fusion Joints in Plastic Pipe

    SciTech Connect

    Connie Reichert

    2005-09-01

    The standard method of joining plastic pipe in the field is the butt fusion process. As in any pipeline application, joint quality greatly affects overall operational safety of the system. Currently no simple, reliable, cost-effective method exists for assessing the quality of fusion joints in the field. Visual examination and pressure testing are current nondestructive approaches, which do not provide any assurance about the long-term pipeline performance. This project developed, demonstrated, and validated an in-situ nondestructive inspection method for butt fusion joints in gas distribution plastic pipelines. The inspection system includes a laser-based image-recognition system that automatically generates and interprets digital images of pipe joints and assigns them a pass/fail rating, which eliminates operator bias in evaluating joint quality. An EWI-patented process, the Weld Zone Inspection Method (WZIM) was developed in which local heat is applied to the joint region to relax the residual stresses formed by the original joining operation, which reveals the surface condition of the joint. In cases where the joint is not formed under optimal conditions, and the intermolecular forces between contacting surfaces are not strong enough, the relaxation of macromolecules in the surface layer causes the material to pull back, revealing a fusion line. If the joint is sound, the bond line image does not develop. To establish initial feasibility of the approach, welds were performed under standard and nonstandard conditions. These welds were subjected to the WZIM and two destructive forms of testing: short-term tensile testing and long-term creep rupture testing. There appears to be a direct correlation between the WZIM and the destructive testing results. Although WZIM appears to be more sensitive than destructive testing can verify, the approach appears valid.

  12. INSPECTION OF FUSION JOINTS IN PLASTIC PIPE

    SciTech Connect

    Alex Savitski; Connie Reichert; John Coffey

    2005-07-13

    The standard method of joining plastic pipe in the field is the butt fusion process. As in any pipeline application, joint quality greatly affects overall operational safety of the system. Currently no simple, reliable, cost effective method of assessing the quality of fusion joints in the field exists. Visual examination and pressure testing are current non-destructive approaches, which do not provide any assurance about the long-term pipeline performance. This project will develop, demonstrate, and validate an in-situ non-destructive inspection method for butt fusion joints in gas distribution plastic pipelines. The inspection system will include a laser based image-recognition system that will automatically generate and interpret digital images of pipe joints and assign them a pass/fail rating, which eliminates operator bias in evaluating joint quality. A Weld Zone Inspection Method (WZIM) is being developed in which local heat is applied to the joint region to relax the residual stresses formed by the original joining operation and reveal the surface condition of the joint. In cases where the joint is not formed under optimal conditions, and the intermolecular forces between contacting surfaces are not strong enough, the relaxation of macromolecules in the surface layer causes the material to pull back, revealing a fusion line. If the joint is sound, the bond line image does not develop. To establish initial feasibility of the approach, welds were performed under standard and nonstandard conditions. These welds were subjected to the WZIM and tensile testing. There appears to be a direct correlation between the WZIM and tensile testing results. Although WZIM appears to be more sensitive than tensile testing can verify, the approach appears valid.

  13. INSPECTION OF FUSION JOINTS IN PLASTIC PIPE

    SciTech Connect

    Alex Savitski; Connie Reichert; John Coffey

    2004-07-13

    The standard method of joining plastic pipe in the field is the butt fusion process. As in any pipeline application, joint quality greatly affects overall operational safety of the system. Currently no simple, reliable, cost effective method of assessing the quality of fusion joints in the field exists. Visual examination and pressure testing are current non-destructive approaches, which do not provide any assurance about the long-term pipeline performance. This project will develop, demonstrate, and validate an in-situ non-destructive inspection method for butt fusion joints in gas distribution plastic pipelines. The inspection system will include a laser based image-recognition system that will automatically generate and interpret digital images of pipe joints and assign them a pass/fail rating, which eliminates operator bias in evaluating joint quality. A Weld Zone Inspection Method (WZIM) is being developed in which local heat is applied to the joint region to relax the residual stresses formed by the original joining operation and reveal the surface condition of the joint. In cases where the joint is not formed under optimal conditions, and the intermolecular forces between contacting surfaces are not strong enough, the relaxation of macromolecules in the surface layer causes the material to pull back, revealing a fusion line. If the joint is sound, the bond line image does not develop. To establish initial feasibility of the approach, welds were performed under standard and non-standard conditions. These welds were subjected to the WZIM and tensile testing. There appears to be a direct correlation between the WZIM and tensile testing results. Although WZIM appears to be more sensitive than tensile testing can verify, the approach appears valid.

  14. INSPECTION OF FUSION JOINTS IN PLASTIC PIPE

    SciTech Connect

    Alex Savitski; Connie Reichert; John Coffey

    2004-10-29

    The standard method of joining plastic pipe in the field is the butt fusion process. As in any pipeline application, joint quality greatly affects overall operational safety of the system. Currently no simple, reliable, cost effective method of assessing the quality of fusion joints in the field exists. Visual examination and pressure testing are current non-destructive approaches, which do not provide any assurance about the long-term pipeline performance. This project will develop, demonstrate, and validate an in-situ non-destructive inspection method for butt fusion joints in gas distribution plastic pipelines. The inspection system will include a laser based image-recognition system that will automatically generate and interpret digital images of pipe joints and assign them a pass/fail rating, which eliminates operator bias in evaluating joint quality. A Weld Zone Inspection Method (WZIM) is being developed in which local heat is applied to the joint region to relax the residual stresses formed by the original joining operation and reveal the surface condition of the joint. In cases where the joint is not formed under optimal conditions, and the intermolecular forces between contacting surfaces are not strong enough, the relaxation of macromolecules in the surface layer causes the material to pull back, revealing a fusion line. If the joint is sound, the bond line image does not develop. To establish initial feasibility of the approach, welds were performed under standard and non-standard conditions. These welds were subjected to the WZIM and tensile testing. There appears to be a direct correlation between the WZIM and tensile testing results. Although WZIM appears to be more sensitive than tensile testing can verify, the approach appears valid.

  15. Control of Internal Transport Barriers in Magnetically Confined Fusion Plasmas

    NASA Astrophysics Data System (ADS)

    Panta, Soma; Newman, David; Sanchez, Raul; Terry, Paul

    2016-10-01

    In magnetic confinement fusion devices the best performance often involves some sort of transport barriers to reduce the energy and particle flow from core to edge. Those barriers create gradients in the temperature and density profiles. If gradients in the profiles are too steep that can lead to instabilities and the system collapses. Control of these barriers is therefore an important challenge for fusion devices (burning plasmas). In this work we focus on the dynamics of internal transport barriers. Using a simple 7 field transport model, extensively used for barrier dynamics and control studies, we explore the use of RF heating to control the local gradients and therefore the growth rates and shearing rates for barrier initiation and control in self-heated fusion plasmas. Ion channel barriers can be formed in self-heated plasmas with some NBI heating but electron channel barriers are very sensitive. They can be formed in self-heated plasmas with additional auxiliary heating i.e. NBI and radio-frequency(RF). Using RF heating on both electrons and ions at proper locations, electron channel barriers along with ion channel barriers can be formed and removed demonstrating a control technique. Investigating the role of pellet injection in controlling the barriers is our next goal. Work supported by DOE Grant DE-FG02-04ER54741.

  16. Role of Fusion Energy in a Sustainable Global Energy Strategy

    SciTech Connect

    Meier, W; Najmabadi, F; Schmidt, J; Sheffield, J

    2001-03-07

    Fusion energy is one of only a few truly long-term energy options. Since its inception in the 1950s, the vision of the fusion energy research program has been to develop a viable means of harnessing the virtually unlimited energy stored in the nuclei of light atoms--the primary fuel deuterium is present as one part in 6,500 of all hydrogen. This vision grew out of the recognition that the immense power radiated by the sun is fueled by nuclear fusion in its hot core. Such high temperatures are a prerequisite for driving significant fusion reactions. The fascinating fourth state of matter at high temperatures is known as plasma. It is only in this fourth state of matter that the nuclei of two light atoms can fuse, releasing the excess energy that was needed to separately bind each of the original two nuclei. Because the nuclei of atoms carry a net positive electric charge, they repel each other. Hydrogenic nuclei, such as deuterium and tritium, must be heated to approximately 100 million degrees Celsius to overcome this electric repulsion and fuse. There have been dramatic recent advances in both the scientific understanding of fusion plasmas and in the generation of fusion power in the laboratory. Today, there is little doubt that fusion energy production is feasible. For this reason, the general thrust of fusion research has focused on configuration improvements leading to an economically competitive product. The risk of conflicts arising from energy shortages and supply cutoffs, as well as the risk of severe environmental impacts from existing methods of energy production, are among the reasons to pursue these opportunities [1]. In this paper we review the tremendous scientific progress in fusion during the last 10 years. We utilize the detailed engineering design activities of burning plasma experiments as well as conceptual fusion power plant studies to describe our visions of attractive fusion power plants. We use these studies to compare technical requirements

  17. A Plan for the Development of Fusion Energy. Final Report to Fusion Energy Sciences Advisory Committee, Fusion Development Path Panel

    SciTech Connect

    None, None

    2003-03-05

    This report presents a plan for the deployment of a fusion demonstration power plant within 35 years, leading to commercial application of fusion energy by mid-century. The plan is derived from the necessary features of a demonstration fusion power plant and from the time scale defined by President Bush. It identifies critical milestones, key decision points, needed major facilities and required budgets.

  18. Fusion characteristics of volcanic ash relevant to aviation hazards

    NASA Astrophysics Data System (ADS)

    Song, Wenjia; Hess, Kai-Uwe; Damby, David E.; Wadsworth, Fabian B.; Lavallée, Yan; Cimarelli, Corrado; Dingwell, Donald B.

    2014-04-01

    The fusion dynamics of volcanic ash strongly impacts deposition in hot parts of jet engines. In this study, we investigate the sintering behavior of volcanic ash using natural ash of intermediate composition, erupted in 2012 at Santiaguito Volcano, Guatemala. A material science procedure was followed in which we monitored the geometrical evolution of cylindrical-shaped volcanic ash compact upon heating from 50 to 1400°C in a heating microscope. Combined morphological, mineralogical, and rheological analyses helped define the evolution of volcanic ash during fusion and sintering and constrain their sticking potential as well as their ability to flow at characteristic temperatures. For the ash investigated, 1240°C marks the onset of adhesion and flowability. The much higher fusibility of ash compared to that of typical test sands demonstrates for the need of a more extensive fusion characterization of volcanic ash in order to mitigate the risk posed on jet engine operation.

  19. Detection of antistaphylococcal and toxic compounds by biological assay systems developed with a reporter Staphylococcus aureus strain harboring a heat inducible promoter - lacZ transcriptional fusion.

    PubMed

    Chanda, Palas Kumar; Ganguly, Tridib; Das, Malabika; Lee, Chia Yen; Luong, Thanh T; Sau, Subrata

    2007-11-30

    Previously it was reported that promoter of groES-groEL operon of Staphylococcus aureus is induced by various cell-wall active antibiotics. In order to exploit the above promoter for identifying novel antistaphylococcal drugs, we have cloned the promoter containing region (P(g)) of groES-groEL operon of S. aureus Newman and found that the above promoter is induced by sublethal concentrations of many antibiotics including cell-wall active antibiotics. A reporter S. aureus RN4220 strain (designated SAU006) was constructed by inserting the P(g)-lacZ transcriptional fusion into its chromosome. Agarose-based assay developed with SAU006 shows that P(g) in single-copy is also induced distinctly by different classes of antibiotics. Data indicate that ciprofloxacin, rifampicin, ampicillin, and cephalothin are strong inducers, whereas, tetracycline, streptomycin and vancomycin induce the above promoter weakly. Sublethal concentrations of ciprofloxacin and ampicilin even have induced P(g) efficiently in microtiter plate grown SAU006. Additional studies show for the first time that above promoter is also induced weakly by arsenate salt and hydrogen peroxide. Taken together, we suggest that our simple and sensitive assay systems with SAU006 could be utilized for screening and detecting not only novel antistaphylococcal compounds but also different toxic chemicals.

  20. Control of a laser inertial confinement fusion-fission power plant

    DOEpatents

    Moses, Edward I.; Latkowski, Jeffery F.; Kramer, Kevin J.

    2015-10-27

    A laser inertial-confinement fusion-fission energy power plant is described. The fusion-fission hybrid system uses inertial confinement fusion to produce neutrons from a fusion reaction of deuterium and tritium. The fusion neutrons drive a sub-critical blanket of fissile or fertile fuel. A coolant circulated through the fuel extracts heat from the fuel that is used to generate electricity. The inertial confinement fusion reaction can be implemented using central hot spot or fast ignition fusion, and direct or indirect drive. The fusion neutrons result in ultra-deep burn-up of the fuel in the fission blanket, thus enabling the burning of nuclear waste. Fuels include depleted uranium, natural uranium, enriched uranium, spent nuclear fuel, thorium, and weapons grade plutonium. LIFE engines can meet worldwide electricity needs in a safe and sustainable manner, while drastically shrinking the highly undesirable stockpiles of depleted uranium, spent nuclear fuel and excess weapons materials.

  1. Photoinduced Fusion of Lipid Bilayer Membranes.

    PubMed

    Suzuki, Yui; Nagai, Ken H; Zinchenko, Anatoly; Hamada, Tsutomu

    2017-03-14

    We have developed a novel system for photocontrol of the fusion of lipid vesicles through the use of a photosensitive surfactant containing an azobenzene moiety (AzoTAB). Real-time microscopic observations clarified a change in both the surface area and internal volume of vesicles during fusion. We also determined the optimal cholesterol concentrations and temperature for inducing fusion. The mechanism of fusion can be attributed to a change in membrane tension, which is caused by the solubilization of lipids through the isomerization of AzoTAB. We used a micropipet technique to estimate membrane tension and discuss the mechanism of fusion in terms of membrane elastic energy. The obtained results regarding this novel photoinduced fusion could lead to a better understanding of the mechanism of membrane fusion in living cells and may also see wider applications, such as in drug delivery and biomimetic material design.

  2. Mechanisms of myoblast fusion during muscle development

    PubMed Central

    Kim, Ji Hoon; Jin, Peng; Duan, Rui; Chen, Elizabeth H.

    2015-01-01

    The development and regeneration of skeletal muscles require the fusion of mononulceated muscle cells to form multinucleated, contractile muscle fibers. Studies using a simple genetic model, Drosophila melanogaster, have discovered many evolutionarily conserved fusion-promoting factors in vivo. Recent work in zebrafish and mouse also identified several vertebrate-specific factors required for myoblast fusion. Here, we integrate progress in multiple in vivo systems and highlight conceptual advance in understanding how muscle cell membranes are brought together for fusion. We focus on the molecular machinery at the fusogenic synapse and present a three-step model to describe the molecular and cellular events leading to fusion pore formation. PMID:25989064

  3. Measuring time of flight of fusion products in an inertial electrostatic confinement fusion device for spatial profiling of fusion reactions

    SciTech Connect

    Donovan, D. C.; Boris, D. R.; Kulcinski, G. L.; Santarius, J. F.; Piefer, G. R.

    2013-03-15

    A new diagnostic has been developed that uses the time of flight (TOF) of the products from a nuclear fusion reaction to determine the location where the fusion reaction occurred. The TOF diagnostic uses charged particle detectors on opposing sides of the inertial electrostatic confinement (IEC) device that are coupled to high resolution timing electronics to measure the spatial profile of fusion reactions occurring between the two charged particle detectors. This diagnostic was constructed and tested by the University of Wisconsin-Madison Inertial Electrostatic Confinement Fusion Group in the IEC device, HOMER, which accelerates deuterium ions to fusion relevant energies in a high voltage ({approx}100 kV), spherically symmetric, electrostatic potential well [J. F. Santarius, G. L. Kulcinski, R. P. Ashley, D. R. Boris, B. B. Cipiti, S. K. Murali, G. R. Piefer, R. F. Radel, T. E. Radel, and A. L. Wehmeyer, Fusion Sci. Technol. 47, 1238 (2005)]. The TOF diagnostic detects the products of D(d,p)T reactions and determines where along a chord through the device the fusion event occurred. The diagnostic is also capable of using charged particle spectroscopy to determine the Doppler shift imparted to the fusion products by the center of mass energy of the fusion reactants. The TOF diagnostic is thus able to collect spatial profiles of the fusion reaction density along a chord through the device, coupled with the center of mass energy of the reactions occurring at each location. This provides levels of diagnostic detail never before achieved on an IEC device.

  4. Fusion bonding of non-pressurized process piping: A new technology and a new approach

    SciTech Connect

    Cooper, R.J.; Pinder, R.

    1996-07-01

    Perhaps the best-known method of thermoplastic fusion bonding for process piping is hot-plate or heated-tool butt welding. Despite the age of this method and the considerable research available on the subject, in practice, this method of heat fusion relies largely on the skill and knowledge of the machine operator. Hence, the quality of the completed fusion bond is largely dependent on human factors. Another method for joining thermoplastic process piping with heat fusion has been through the use of electrofusion fittings or couplings. A sleeve with an embedded resistance wire is slipped onto mating pipe ends, and welding takes place by electrically heating the resistance wire and forming a molecular bond on the outside surface of the mated pipes. While butt welding tends to rely heavily on the knowledge and experience of the machine operator, electrofusion fittings tend to rely more on automated mechanisms such as the software in the computerized fusion box. An alternative form of thermoplastic welding that employs the features of both butt welding and electrofusion couplings has recently been developed. This unique method employs the principles of electrofusion for performing butt welding. The authors have successfully demonstrated this technology at a major US chemical manufacturer`s facility to produce reliable, leak-tight fusion joints in non-pressurized, process piping applications. Research and practical experience were blended to provide consistent fusion quality based on monitoring key fusion parameters, while still relying on the experience and training of a fusion operator.

  5. Investigation of condensed matter fusion

    SciTech Connect

    Jones, S.E.; Berrondo, M.; Czirr, J.B.; Decker, D.L.; Harrison, K.; Jensen, G.L.; Palmer, E.P.; Rees, L.B.; Taylor, S.; Vanfleet, H.B.; Wang, J.C.; Bennion, D.N.; Harb, J.N.; Pitt, W.G.; Thorne, J.M.; Anderson, A.N.; McMurtry, G.; Murphy, N.; Goff, F.E.

    1990-12-01

    Work on muon-catalyzed fusion led to research on a possible new type of fusion occurring in hydrogen isotopes embedded in metal lattices. While the nuclear-product yields observed to date are so small as to require careful further checking, rates observed over short times appear sufficiently large to suggest that significant neutrons and triton yields could be realized -- if the process could be understood and controlled. During 1990, we have developed two charged-particle detection systems and three new neutron detectors. A segmented, high-efficiency neutron counter was taken into 600 m underground in a mine in Colorado for studies out of the cosmic-ray background. Significant neutron emissions were observed in this environment in both deuterium-gas-loaded metals and in electrolytic cells, confirming our earlier observations.

  6. Effects of selective fusion on the thermal history of the earth's mantle

    USGS Publications Warehouse

    Lee, W.H.K.

    1968-01-01

    A comparative study on the thermal history of the earth's mantle was made by numerical solutions of the heat equation including and excluding selective fusion of silicates. Selective fusion was approximated by melting in a multicomponent system and redistribution of radioactive elements. Effects of selective fusion on the thermal models are (1) lowering (by several hundred degrees centigrade) and stabilizing the internal temperature distribution, and (2) increasing the surface heat-flow. It was found that models with selective fusion gave results more compatible with observations of both present temperature and surface heat-flow. The results therefore suggest continuous differentiation of the earth's mantle throughout geologic time, and support the hypothesis that the earth's atmosphere, oceans, and crust have been accumulated throughout the earth's history by degassing and selective fusion of the mantle. ?? 1968.

  7. Studies on the fusion peptide of a paramyxovirus fusion glycoprotein: roles of conserved residues in cell fusion.

    PubMed Central

    Horvath, C M; Lamb, R A

    1992-01-01

    The role of residues in the conserved hydrophobic N-terminal fusion peptide of the paramyxovirus fusion (F) protein in causing cell-cell fusion was examined. Mutations were introduced into the cDNA encoding the simian virus 5 (SV5) F protein, the altered F proteins were expressed by using an eukaryotic vector, and their ability to mediate syncytium formation was determined. The mutant F proteins contained both single- and multiple-amino-acid substitutions, and they exhibited a variety of intracellular transport properties and fusion phenotypes. The data indicate that many substitutions in the conserved amino acids of the simian virus 5 F fusion peptide can be tolerated without loss of biological activity. Mutant F proteins which were not transported to the cell surface did not cause cell-cell fusion, but all of the mutants which were transported to the cell surface were fusion competent, exhibiting fusion properties similar to or better than those of the wild-type F protein. Mutant F proteins containing glycine-to-alanine substitutions had altered intracellular transport characteristics, yet they exhibited a great increase in fusion activity. The potential structural implications of this substitution and the possible importance of these glycine residues in maintaining appropriate levels of fusion activity are discussed. Images PMID:1548771

  8. Inertial Fusion Power Plant Concept of Operations and Maintenance

    SciTech Connect

    Anklam, T.; Knutson, B.; Dunne, A. M.; Kasper, J.; Sheehan, T.; Lang, D.; Roberts, V.; Mau, D.

    2015-01-15

    Parsons and LLNL scientists and engineers performed design and engineering work for power plant pre-conceptual designs based on the anticipated laser fusion demonstrations at the National Ignition Facility (NIF). Work included identifying concepts of operations and maintenance (O&M) and associated requirements relevant to fusion power plant systems analysis. A laser fusion power plant would incorporate a large process and power conversion facility with a laser system and fusion engine serving as the heat source, based in part on some of the systems and technologies advanced at NIF. Process operations would be similar in scope to those used in chemical, oil refinery, and nuclear waste processing facilities, while power conversion operations would be similar to those used in commercial thermal power plants. While some aspects of the tritium fuel cycle can be based on existing technologies, many aspects of a laser fusion power plant presents several important and unique O&M requirements that demand new solutions. For example, onsite recovery of tritium; unique remote material handling systems for use in areas with high radiation, radioactive materials, or high temperatures; a five-year fusion engine target chamber replacement cycle with other annual and multi-year cycles anticipated for major maintenance of other systems, structures, and components (SSC); and unique SSC for fusion target waste recycling streams. This paper describes fusion power plant O&M concepts and requirements, how O&M requirements could be met in design, and how basic organizational and planning issues can be addressed for a safe, reliable, economic, and feasible fusion power plant.

  9. Inertial fusion power plant concept of operations and maintenance

    NASA Astrophysics Data System (ADS)

    Knutson, Brad; Dunne, Mike; Kasper, Jack; Sheehan, Timothy; Lang, Dwight; Anklam, Tom; Roberts, Valerie; Mau, Derek

    2015-02-01

    Parsons and LLNL scientists and engineers performed design and engineering work for power plant pre-conceptual designs based on the anticipated laser fusion demonstrations at the National Ignition Facility (NIF). Work included identifying concepts of operations and maintenance (O&M) and associated requirements relevant to fusion power plant systems analysis. A laser fusion power plant would incorporate a large process and power conversion facility with a laser system and fusion engine serving as the heat source, based in part on some of the systems and technologies advanced at NIF. Process operations would be similar in scope to those used in chemical, oil refinery, and nuclear waste processing facilities, while power conversion operations would be similar to those used in commercial thermal power plants. While some aspects of the tritium fuel cycle can be based on existing technologies, many aspects of a laser fusion power plant presents several important and unique O&M requirements that demand new solutions. For example, onsite recovery of tritium; unique remote material handling systems for use in areas with high radiation, radioactive materials, or high temperatures; a five-year fusion engine target chamber replacement cycle with other annual and multi-year cycles anticipated for major maintenance of other systems, structures, and components (SSC); and unique SSC for fusion target waste recycling streams. This paper describes fusion power plant O&M concepts and requirements, how O&M requirements could be met in design, and how basic organizational and planning issues can be addressed for a safe, reliable, economic, and feasible fusion power plant.

  10. A viable process for producing hydrogen synfuel using nuclear fusion heat

    NASA Astrophysics Data System (ADS)

    Galloway, T. R.; Brown, L. C.

    Analytical and costing analyses of a thermochemical water splitting plant powered by a tandem mirror fusion reactor are presented. Design criteria indicated directing high quality steam to the chemical plant, where no liquid metal coolants would be used. Minimal pumping distances for high pressure He, multiple barriers between the neutron-activated blanket and the hydrogen product, and modular construction where possible are necessary. A He-Brayton topping cycle, coupled to a steam-Rankine bottoming cycle are selected. Slightly over 1111 MWt and about 720 MWe could be produced by the plant if all low grade waste heat is directed to the Rankine cycle. SO3 is used with water for the splitting process, then recombined. H2 is siphoned off as a fuel and O2 is delivered to a coal reforming plant. A 30 yr plant life is projected, operating at a 70% thermal efficiency for the splitting process and producing H2 at $10-12/GJ. The plant is expected to become economically viable in the year 2030 if debt financing is available at 12.25% per year.

  11. Magnetic fusion energy plasma interactive and high heat flux components. Volume III. Strategy for international collaborations in the areas of plasma materials interactions and high heat flux materials and components development

    SciTech Connect

    Gauster, W.B.; Bauer, W.; Roberto, J.B.; Post, D.E.

    1984-01-01

    The purpose of this summary is to assess opportunities for such collaborations in the specific areas of Plasma Materials Interaction and High Heat Flux Materials and Components Development, and to aid in developing a strategy to take advantage of them. After some general discussion of international collaborations, we summarize key technical issues and the US programs to address them. Then follows a summary of present collaborations and potential opportunities in foreign laboratories.

  12. Enhancement of Fusion Rate by Superthermal Tritium Ions

    NASA Astrophysics Data System (ADS)

    Castaldo, Carmine; Cardinali, Alessandro; Marinucci, Massimo

    2011-10-01

    We propose a new concept of a nuclear fusion reactor. It is based on the enhancement of the DT fusion rate in tokamak plasmas by a superthermal population of Tritium ions heated by ICRH. It was already shown that break-even conditions might be reached [C. Castaldo and A. Cardinali, Phys. Plasmas 17, 072513 (2010)]. Here we show that Q ~20, suitable for nuclear fusion power station, can be achieved in a compact tokamak configuration (major radius R=160cm, minor radius a=55cm, elongation k=1.9, triangularity δ=0.4, q95=3.5), operating with IP=8MA plasma current, BT=11.3T toroidal field, line averaged plasma density n=5X1020m-3, and 40% D, 35% H, 25% T concentrations of the Hydrogen isotopes. The burning plasma is obtained by the injection of 15 MW ICRF power, coupled by six antennas, with radiating areas of 0.25m2, at the operating frequency f=125 MHz and toroidal wave number n//=4. The heating scenario has been analyzed by the code TORIC, and approximated analytical equilibria are considered. As a result the total fusion power expected for the proposed scenario is about 350MW, with Q ~20, assuming that at least 70% of the fusion power carried by the α particles is absorbed by the electrons in the plasma core so that the expected central plasma temperature is about 10keV.

  13. Study of fusion Q-value rule in sub-barrier fusion of heavy ions

    NASA Astrophysics Data System (ADS)

    Liu, Xing-Xing; Zhang, Gao-Long; Zhang, Huan-Qiao

    2015-07-01

    A vast body of fusion data has been analyzed for different projectiles and target nuclei. It is indicated that the sub-barrier fusion depends on the fusion Q-value. In terms of a recently introduced fusion Q-value rule and an energy scaling reduction procedure, the experimental fusion excitation functions are reduced and compared with each other. It is found that the reduced fusion excitations of selected fusion systems show a similar trend. The fusion data for massive nuclei are in agreement with the Q-value rule. In the fusion process, the Q contribution should be considered. Within this approach, the sub-barrier fusion cross sections of most fusion systems can be predicted without involving any structure effects of colliding nuclei. Instances of disagreement are presented in a few fusion systems. The use of the energy scaling as a criterion of possible experimental data inconsistency is discussed. More precise experimental fusion data need to be measured. Supported by National Nature Science Foundation of China (11475013, 11035007, 11175011), State Key Laboratory of Software Development Environment (SKLSDE-2014ZX-08), Fundamental Research Funds for the Central Universities and the Key Laboratory of High Precision Nuclear Spectroscopy, Institute of Modern Physics, Chinese Academy of Sciences

  14. Spherically symmetric simulation of plasma liner driven magnetoinertial fusion

    SciTech Connect

    Samulyak, Roman; Parks, Paul; Wu Lingling

    2010-09-15

    Spherically symmetric simulations of the implosion of plasma liners and compression of plasma targets in the concept of the plasma jet driven magnetoinertial fusion have been performed using the method of front tracking. The cases of single deuterium and xenon liners and double layer deuterium-xenon liners compressing various deuterium-tritium targets have been investigated, optimized for maximum fusion energy gains, and compared with theoretical predictions and scaling laws of [P. Parks, Phys. Plasmas 15, 062506 (2008)]. In agreement with the theory, the fusion gain was significantly below unity for deuterium-tritium targets compressed by Mach 60 deuterium liners. The most optimal setup for a given chamber size contained a target with the initial radius of 20 cm compressed by a 10 cm thick, Mach 60 xenon liner, achieving a fusion energy gain of 10 with 10 GJ fusion yield. Simulations also showed that composite deuterium-xenon liners reduce the energy gain due to lower target compression rates. The effect of heating of targets by alpha particles on the fusion energy gain has also been investigated.

  15. Magnetic fusion driventransmutation of nuclear waste (FTW)

    SciTech Connect

    Peng, Yueng Kay Martin; Cheng, E.T.

    1993-01-01

    The possibility of magnetic Fusion driven Transmutation of Waste (FTW) was revisted and discussed recently. Nuclear wastes include all transuranium elements: Pu isotopes, minor actinides separated from the spent fission fuel, and fissile products. Elimination of thse long-life nuclear wastes is necessary for the long-term viability of fission power. A Small Business Innovative Research program has been initiated under the leadership of TSI Research to examine the efficacy of fusion transmutation of waste utilizing small fusion drivers.

  16. Estimating the melting point, entropy of fusion, and enthalpy of fusion of organic compounds via SPARC

    EPA Science Inventory

    The entropies of fusion, enthalies of fusion, and melting points of organic compounds can be estimated through three models developed using the SPARC (SPARC Performs Automated Reasoning in Chemistry) platform. The entropy of fusion is modeled through a combination of interaction ...

  17. Carbon Nanotubes Mediate Fusion of Lipid Vesicles.

    PubMed

    Bhaskara, Ramachandra M; Linker, Stephanie M; Vögele, Martin; Köfinger, Jürgen; Hummer, Gerhard

    2017-02-28

    The fusion of lipid membranes is opposed by high energetic barriers. In living organisms, complex protein machineries carry out this biologically essential process. Here we show that membrane-spanning carbon nanotubes (CNTs) can trigger spontaneous fusion of small lipid vesicles. In coarse-grained molecular dynamics simulations, we find that a CNT bridging between two vesicles locally perturbs their lipid structure. Their outer leaflets merge as the CNT pulls lipids out of the membranes, creating an hourglass-shaped fusion intermediate with still intact inner leaflets. As the CNT moves away from the symmetry axis connecting the vesicle centers, the inner leaflets merge, forming a pore that completes fusion. The distinct mechanism of CNT-mediated membrane fusion may be transferable, providing guidance in the development of fusion agents, e.g., for the targeted delivery of drugs or nucleic acids.

  18. History of Nuclear Fusion Research in Japan

    NASA Astrophysics Data System (ADS)

    Iguchi, Harukazu; Matsuoka, Keisuke; Kimura, Kazue; Namba, Chusei; Matsuda, Shinzaburo

    In the late 1950s just after the atomic energy research was opened worldwide, there was a lively discussion among scientists on the strategy of nuclear fusion research in Japan. Finally, decision was made that fusion research should be started from the basic, namely, research on plasma physics and from cultivation of human resources at universities under the Ministry of Education, Science and Culture (MOE). However, an endorsement was given that construction of an experimental device for fusion research would be approved sooner or later. Studies on toroidal plasma confinement started at Japan Atomic Energy Research Institute (JAERI) under the Science and Technology Agency (STA) in the mid-1960s. Dualistic fusion research framework in Japan was established. This structure has lasted until now. Fusion research activities over the last 50 years are described by the use of a flowchart, which is convenient to glance the historical development of fusion research in Japan.

  19. Review of alternative concepts for magnetic fusion

    SciTech Connect

    Krakowski, R.A.; Miller, R.L.; Hagenson, R.L.

    1980-01-01

    Although the Tokamak represents the mainstay of the world's quest for magnetic fusion power, with the tandem mirror serving as a primary backup concept in the US fusion program, a wide range of alternative fusion concepts (AFC's) have been and are being pursued. This review presents a summary of past and present reactor projections of a majority of AFC's. Whenever possible, quantitative results are given.

  20. Influence of breakup on fusion barrier distributions

    NASA Astrophysics Data System (ADS)

    Patel, D.; Nayak, B. K.; Mukherjee, S.; Biswas, D. C.; Mirgule, E. T.; John, B. V.; Gupta, Y. K.; Mukhopadhyay, S.; Prajapati, G.; Danu, L. S.; Rath, P. K.; Desai, V.; Deshmukh, N.; Saxena, A.

    2013-04-01

    Fusion barrier distributions have been extracted from the quasi-elastic scattering excitation functions, measured at backward angle θlab = 160° in reactions of 6,7Li+209Bi. The present results have been compared with the barrier distributions obtained from the fusion excitation function measurements for the above mentioned systems. The fusion barrier distributions from the quasi-elastic scattering excitation functions have been analyzed with simplified Coupled Channels calculations using Fresco. Inclusions of resonant states for both 6,7Li projectiles improve the predictions to describe the measured quasi-elastic scattering excitation functions and barrier distributions. For both the reactions peak positions of fusion barrier distributions are shifted towards a lower energy side in comparison to that obtained from the fusion excitation function measurements. The observed discrepancy in peak positions of barrier distributions obtained from quasi-elastic scattering and fusion excitation function measurements has been discussed in terms of total reaction threshold distribution.

  1. Observations of membrane fusion in a liposome dispersion: the missing fusion intermediate?

    PubMed Central

    Foldvari, Marianna

    2015-01-01

    Early intermediate structures of liposome-liposome fusion events were captured by freeze-fracture electron microscopic (EM) technique. The images show the morphology of the fusion interface at several different stages of the fusion event. One of the intermediates was captured at a serendipitous stage of two vesicles’ membranes (both leaflets) merging and their contents starting to intermix clearly showing the fusion interface with a previously unseen fusion rim. From the morphological information a hypothetical sequence of the fusion event and corresponding lipid structural arrangements are described. PMID:26069726

  2. Experimental Test of the Polarization Persistence in Inertial Confinement Fusion

    NASA Astrophysics Data System (ADS)

    Didelez, J. P.; Deutsch, C.; Fujiwara, M.; Nakai, M.; Utsuro, M.

    2016-03-01

    The complete deuteron and triton polarization in the DT fusion increases the reactivity by 50%. For Inertial Confinement Fusion (ICF), due to the dynamics of the fusion reaction process, the fusion rate could even be further increased. It has been argued that the polarization would survive as well in magnetic as in inertial confinements. Recently, we have proposed an experiment to test the persistence of the polarization in a fusion process, using a powerful laser hitting a polarized HD target.The polarized deuterons heated in the plasma induced by the laser can fuse. The corresponding reaction is: D + D → 3He + n. The angular distribution of the emitted neutrons and the change in the corresponding total cross section are signatures to estimate the polarization persistency. A proposal to test the persistence of the polarization in ICF has been accepted at ILE: the POLAF project (POlarization in LAser Fusion Process). It uses the polarized HD targets produced at RCNP and the powerful ILE lasers, as well as the neutron detectors existing there. Both institutions are on the same campus at Osaka University. The description of the POLAF experiment and of the corresponding set-up is given.

  3. Fusion of experimental data

    NASA Astrophysics Data System (ADS)

    Di Gesú, Vito; Maccarone, Maria Concetta

    The integration of information from various sensory systems is one of the most difficult challenges in understanding both perception and cognition. For example, the problem of auditory-visual integration is a correspondence problem between perceived auditory and visual scenes. Two main questions arise when designing data analysis systems: what is the useful information to be integrated?, and what are the integration rules? The problem of integrating information becomes relevant whenever: (a) the same kind of data are detected by spatially distributed sensors; (b) heterogeneous data are detected by different sensors; (c) heterogeneous distributed data are involved. General problems concerning the integration of experimental data are reviewed. The case of the BeppoSAX X-ray astronomical satellite is given as an example.

  4. Simulation of MTF experiments at General Fusion

    NASA Astrophysics Data System (ADS)

    Reynolds, Meritt; Froese, Aaron; Barsky, Sandra; Devietien, Peter; Toth, Gabor; Brennan, Dylan; Hooper, Bick

    2016-10-01

    General Fusion (GF) aims to develop a magnetized target fusion (MTF) power plant based on compression of magnetically-confined plasma by liquid metal. GF is testing this compression concept by collapsing solid aluminum liners onto spheromak or tokamak plasmas. To simulate the evolution of the compressing plasma in these experiments, we integrated a moving-mesh method into a finite-volume MHD code (VAC). The single-fluid model includes temperature-dependent resistivity and anisotropic heat transport. The trajectory of the liner is based on experiments and LS-DYNA simulations. During compression the geometry remains axially symmetric, but the MHD simulation is fully 3D to capture ideal and resistive plasma instabilities. We compare simulation to experiment through the primary diagnostic of Mirnov probes embedded in the inner coaxial surface against which the magnetic flux and plasma are compressed by the imploding liner. The MHD simulation reproduces the appearance of n=1 mode activity observed in experiments performed in negative D-shape geometry (MRT and PROSPECTOR machines). The same code predicts more favorable compression in spherical tokamak geometry, having positive D-shape (SPECTOR machine).

  5. The Dark Side of Cell Fusion

    PubMed Central

    Bastida-Ruiz, Daniel; Van Hoesen, Kylie; Cohen, Marie

    2016-01-01

    Cell fusion is a physiological cellular process essential for fertilization, viral entry, muscle differentiation and placental development, among others. In this review, we will highlight the different cancer cell-cell fusions and the advantages obtained by these fusions. We will specially focus on the acquisition of metastatic features by cancer cells after fusion with bone marrow-derived cells. The mechanism by which cancer cells fuse with other cells has been poorly studied thus far, but the presence in several cancer cells of syncytin, a trophoblastic fusogen, leads us to a cancer cell fusion mechanism similar to the one used by the trophoblasts. The mechanism by which cancer cells perform the cell fusion could be an interesting target for cancer therapy. PMID:27136533

  6. Linear optimal control of tokamak fusion devices

    SciTech Connect

    Kessel, C.E.; Firestone, M.A.; Conn, R.W.

    1989-05-01

    The control of plasma position, shape and current in a tokamak fusion reactor is examined using linear optimal control. These advanced tokamaks are characterized by non up-down symmetric coils and structure, thick structure surrounding the plasma, eddy currents, shaped plasmas, superconducting coils, vertically unstable plasmas, and hybrid function coils providing ohmic heating, vertical field, radial field, and shaping field. Models of the electromagnetic environment in a tokamak are derived and used to construct control gains that are tested in nonlinear simulations with initial perturbations. The issues of applying linear optimal control to advanced tokamaks are addressed, including complex equilibrium control, choice of cost functional weights, the coil voltage limit, discrete control, and order reduction. Results indicate that the linear optimal control is a feasible technique for controlling advanced tokamaks where the more common classical control will be severely strained or will not work. 28 refs., 13 figs.

  7. Modes of Paramyxovirus Fusion: a Henipavirus perspective

    PubMed Central

    Lee, Benhur; Akyol-Ataman, Zeynep

    2011-01-01

    Henipavirus is a new genus of paramyxovirus that uses protein-based receptors (EphrinB2 and EphrinB3) for virus entry. Paramyxovirus entry requires the coordinated action of the fusion (F) and attachment viral envelope glycoproteins. Receptor binding to the attachment protein triggers F to undergo a conformational cascade that results in membrane fusion. The accumulation of structural and functional studies on many paramyxoviral fusion and attachment proteins, including recent structures of Nipah and Hendra virus G bound and unbound to cognate ephrinB receptors, indicate that henipavirus entry and fusion differs mechanistically from paramyxoviruses that use glycan-based receptors. PMID:21511478

  8. Inhibition of HIV-1 by fusion inhibitors.

    PubMed

    Eggink, Dirk; Berkhout, Ben; Sanders, Rogier W

    2010-01-01

    The envelope glycoprotein complex (Env) is responsible for entry of the human immunodeficiency virus type 1 (HIV-1) into cells by mediating attachment to target cells and subsequent membrane fusion. Env consists of three gp120 subunits that mediate receptor and co-receptor attachment and three gp41 subunits responsible for membrane fusion. Several steps of the entry process can serve as drug targets. Receptor antagonists prevent attachment of gp120 to the receptor or co-receptor and conformational changes within gp41 required for membrane fusion can be inhibited by fusion inhibitors. Enfuvirtide (T20, Fuzeon) is a peptide based on the gp41 sequence and is the only approved fusion inhibitor. It prevents membrane fusion by competitively binding to gp41 and blocking the formation of the post-fusion structure. New generations of T20-like peptides have been developed with improved potency and stability. Besides T20 and derivatives, other fusion inhibitors have been developed that target different domains of gp41. Here we discuss the development of fusion inhibitors, their mode of action and their potential for incorporation in future drug regimens.

  9. Optimization of the SHX Fusion Powered Transatmospheric Propulsion Concept

    NASA Technical Reports Server (NTRS)

    Adams, Robert B.; Landrum, D. Brian

    2001-01-01

    Existing propulsion technology has not achieved cost effective payload delivery rates to low earth orbit. A fusion based propulsion system, denoted as the Simultaneous Heating and eXpansion (SHX) engine, has been proposed in earlier papers. The SHX couples energy generated by a fusion reactor to the engine flowpath by use of coherent beam emitters. A quasi-one-dimensional flow model was used to quantify the effects of area expansion and energy input on propulsive efficiency for several beam models. Entropy calculations were included to evaluate the lost work in the system.

  10. Massachusetts Institute of Technology Plasma Fusion Center 1992--1993 report to the President

    SciTech Connect

    Not Available

    1993-07-01

    This report discusses research being conducted at MIT`s plasma fusion center. Some of the areas covered are: plasma diagnostics; rf plasma heating; gyrotron research; treatment of solid waste by arc plasma; divertor experiments; tokamak studies; and plasma and fusion theory.

  11. Lipids as modulators of membrane fusion mediated by viral fusion proteins.

    PubMed

    Teissier, Elodie; Pécheur, Eve-Isabelle

    2007-11-01

    Enveloped viruses infect host cells by fusion of viral and target membranes. This fusion event is triggered by specific glycoproteins in the viral envelope. Fusion glycoproteins belong to either class I, class II or the newly described third class, depending upon their arrangement at the surface of the virion, their tri-dimensional structure and the location within the protein of a short stretch of hydrophobic amino acids called the fusion peptide, which is able to induce the initial lipid destabilization at the onset of fusion. Viral fusion occurs either with the plasma membrane for pH-independent viruses, or with the endosomal membranes for pH-dependent viruses. Although, viral fusion proteins are parted in three classes and the subcellular localization of fusion might vary, these proteins have to act, in common, on lipid assemblies. Lipids contribute to fusion through their physical, mechanical and/or chemical properties. Lipids can thus play a role as chemically defined entities, or through their preferential partitioning into membrane microdomains called "rafts", or by modulating the curvature of the membranes involved in the fusion process. The purpose of this review is to make a state of the art on recent findings on the contribution of cholesterol, sphingolipids and glycolipids in cell entry and membrane fusion of a number of viral families, whose members bear either class I or class II fusion proteins, or fusion proteins of the recently discovered third class.

  12. Estimating the melting point, entropy of fusion, and enthalpy of fusion of organic compounds via SPARC.

    PubMed

    Whiteside, T S; Hilal, S H; Brenner, A; Carreira, L A

    2016-08-01

    The entropy of fusion, enthalpy of fusion, and melting point of organic compounds can be estimated through three models developed using the SPARC (SPARC Performs Automated Reasoning in Chemistry) platform. The entropy of fusion is modelled through a combination of interaction terms and physical descriptors. The enthalpy of fusion is modelled as a function of the entropy of fusion, boiling point, and flexibility of the molecule. The melting point model is the enthalpy of fusion divided by the entropy of fusion. These models were developed in part to improve SPARC's vapour pressure and solubility models. These models have been tested on 904 unique compounds. The entropy model has a RMS of 12.5 J mol(-1) K(-1). The enthalpy model has a RMS of 4.87 kJ mol(-1). The melting point model has a RMS of 54.4°C.

  13. Method of controlling fusion reaction rates

    DOEpatents

    Kulsrud, Russell M.; Furth, Harold P.; Valeo, Ernest J.; Goldhaber, Maurice

    1988-01-01

    A method of controlling the reaction rates of the fuel atoms in a fusion reactor comprises the step of polarizing the nuclei of the fuel atoms in a particular direction relative to the plasma confining magnetic field. Fusion reaction rates can be increased or decreased, and the direction of emission of the reaction products can be controlled, depending on the choice of polarization direction.

  14. Method of controlling fusion reaction rates

    DOEpatents

    Kulsrud, Russell M.; Furth, Harold P.; Valeo, Ernest J.; Goldhaber, Maurice

    1988-03-01

    A method of controlling the reaction rates of the fuel atoms in a fusion reactor comprises the step of polarizing the nuclei of the fuel atoms in a particular direction relative to the plasma confining magnetic field. Fusion reaction rates can be increased or decreased, and the direction of emission of the reaction products can be controlled, depending on the choice of polarization direction.

  15. Experimental Investigation of Ternary Alloys for Fusion Breeding Blankets

    SciTech Connect

    Choi, B. William; Chiu, Ing L.

    2015-10-26

    Future fusion power plants based on the deuterium-tritium (DT) fuel cycle will be required to breed the T fuel via neutron reactions with lithium, which will be incorporated in a breeding blanket that surrounds the fusion source. Recent work by LLNL proposed the used of liquid Li as the breeder in an inertial fusion energy (IFE) power plant. Subsequently, an LDRD was initiated to develop alternatives ternary alloy liquid metal breeders that have reduced chemical reactivity with water and air compared to pure Li. Part of the work plan was to experimentally investigate the phase diagrams of ternary alloys. Of particular interest was measurement of the melt temperature, which must be low enough to be compatible with the temperature limits of the steel used in the construction of the chamber and heat transfer system.

  16. Charge exchange recombination spectroscopy measurements in the extreme ultraviolet region of central carbon concentrations during high power neutral beam heating in TFTR (Tokamak Fusion Test Reactor)

    SciTech Connect

    Stratton, B.C.; Fonck, R.J.; Ramsey, A.T.; Synakowski, E.J.; Grek, B.; Hill, K.W.; Johnson, D.W.; Mansfield, D.K.; Park, H.; Taylor, G.; Valanju, P.M. . Plasma Physics Lab.; Texas Univ., Austin, TX . Fusion Research Center)

    1989-09-01

    The carbon concentration in the central region of TFTR discharges with high power neutral beam heating has been measured by charge-extracted recombination spectroscopy (CXRS) of the C{sup +5} n = 3--4 transition in the extreme ultraviolet region. The carbon concentrations were deduced from absolute measurements of the line brightness using a calculation of the beam attenuation and the appropriate cascade-corrected line excitation rates. As a result of the high ion temperatures in most of the discharges, the contribution of beam halo neutrals to the line brightness was significant and therefore had to be included in the modeling of the data. Carbon concentrations have been measured in discharges with I{sub p} = 1.0-1.6 MA and beam power in the range of 2.6-30 MW, including a number of supershots. The results are in good agreement with carbon concentrations deduced from the visible bremsstrahlung Z{sub eff} and metallic impurity concentrations measured by x-ray pulse-height analysis, demonstrating the reliability of the atomic rates used in the beam attenuation and line excitation calculations. Carbon is the dominant impurity species in these discharges; the oxygen concentration measured via CXRS in a high beam power case was 0.0006 of n{sub e}, compard to 0.04 for carbon. Trends with I{sub p} and beam power in the carbon concentration and the inferred deuteron concentration are presented. The carbon concentration is independent of I{sub p} and decreases from 0.13 at 2.6 MW beam power to 0.04 at 30 MW, while the deuteron concentration increases from 0.25 to 0.75 over the same range of beam power. These changes are primarily the result of beam particle fueling, as the carbon density did not vary significantly with beam power. The time evolutions of the carbon and deuteron concentrations during two high power beam pulses, one which exhibited a carbon bloom and one which did not, are compared. 30 refs., 12 figs., 2 tabs.

  17. Highlights of the heavy ion fusion symposium

    SciTech Connect

    Keefe, D.

    1986-07-01

    The current status and prospects for inertial confinement fusion based on the use of intense beams of heavy ions will be described in the light of results presented at the International Symposium on Heavy Ion Fusion, (Washington, DC, May 27-29, 1986).

  18. Computer Modeling of a Fusion Plasma

    SciTech Connect

    Cohen, B I

    2000-12-15

    Progress in the study of plasma physics and controlled fusion has been profoundly influenced by dramatic increases in computing capability. Computational plasma physics has become an equal partner with experiment and traditional theory. This presentation illustrates some of the progress in computer modeling of plasma physics and controlled fusion.

  19. Mechanics of membrane fusion/pore formation.

    PubMed

    Fuhrmans, Marc; Marelli, Giovanni; Smirnova, Yuliya G; Müller, Marcus

    2015-01-01

    Lipid bilayers play a fundamental role in many biological processes, and a considerable effort has been invested in understanding their behavior and the mechanism of topological changes like fusion and pore formation. Due to the time- and length-scale on which these processes occur, computational methods have proven to be an especially useful tool in their study. With their help, a number of interesting findings about the shape of fusion intermediates could be obtained, and novel hypotheses about the mechanism of topological changes and the involvement of peptides therein were suggested. In this work, we try to present a summary of these developments together with some hitherto unpublished results, featuring, among others, the shape of stalks and fusion pores, possible modes of action of the influenza HA fusion peptide and the SNARE protein complex, the mechanism of supported lipid bilayer formation by vesicle spreading, and the free energy and transition pathway of the fusion process.

  20. Introduction to Nuclear Fusion Power and the Design of Fusion Reactors. An Issue-Oriented Module.

    ERIC Educational Resources Information Center

    Fillo, J. A.

    This three-part module focuses on the principles of nuclear fusion and on the likely nature and components of a controlled-fusion power reactor. The physical conditions for a net energy release from fusion and two approaches (magnetic and inertial confinement) which are being developed to achieve this goal are described. Safety issues associated…

  1. Dependence of fusion on isospin dynamics

    NASA Astrophysics Data System (ADS)

    Godbey, K.; Umar, A. S.; Simenel, C.

    2017-01-01

    We introduce a new microscopic approach to calculate the dependence of fusion barriers and cross sections on isospin dynamics. The method is based on the time-dependent Hartree-Fock theory and the isoscalar and isovector properties of the energy density functional (EDF). The contribution to the fusion barriers originating from the isoscalar and isovector parts of the EDF is calculated. It is shown that, for nonsymmetric systems, the isovector dynamics influence the subbarrier fusion cross sections. For most systems this results in an enhancement of the subbarrier cross sections, while for others we observe differing degrees of hindrance. We use this approach to provide an explanation of recently measured fusion cross sections which show a enhancement at low Ec .m . energies for the system 40Ca+132Sn as compared with the more neutron-rich system 48Ca+132Sn and discuss the dependence of subbarrier fusion cross sections on transfer.

  2. Status of beryllium development for fusion applications

    SciTech Connect

    Billone, M.C.; Donne, M.D.; Macaulay-Newcombe, R.G.

    1994-05-01

    Beryllium is a leading candidate material for the neutron multiplier of tritium breeding blankets and the plasma facing component of first wall and divertor systems. Depending on the application, the fabrication methods proposed include hot-pressing, hot-isostatic-pressing, cold isostatic pressing/sintering, rotary electrode processing and plasma spraying. Product forms include blocks, tubes, pebbles, tiles and coatings. While, in general, beryllium is not a leading structural material candidate, its mechanical performance, as well its performance with regard to sputtering, heat transport, tritium retention/release, helium-induced swelling and chemical compatibility, is an important consideration in first-wall/blanket design. Differential expansion within the beryllium causes internal stresses which may result in cracking, thereby affecting the heat transport and barrier performance of the material. Overall deformation can result in loading of neighboring structural material. Thus, in assessing the performance of beryllium for fusion applications, it is important to have a good database in all of these performance areas, as well as a set of properties correlations and models for the purpose of interpolation/extrapolation.

  3. Status of cold fusion (2010).

    PubMed

    Storms, Edmund

    2010-10-01

    The phenomenon called cold fusion has been studied for the last 21 years since its discovery by Profs. Fleischmann and Pons in 1989. The discovery was met with considerable skepticism, but supporting evidence has accumulated, plausible theories have been suggested, and research is continuing in at least eight countries. This paper provides a brief overview of the major discoveries and some of the attempts at an explanation. The evidence supports the claim that a nuclear reaction between deuterons to produce helium can occur in special materials without application of high energy. This reaction is found to produce clean energy at potentially useful levels without the harmful byproducts normally associated with a nuclear process. Various requirements of a model are examined.

  4. Lenr and "cold Fusion" Excess Heat:. Their Relation to Other Anomalous Microphysical Energy Experiments and Emerging New Energy Technologies

    NASA Astrophysics Data System (ADS)

    Mallove, Eugene F.

    2005-12-01

    During the past 15 years, indisputable experimental evidence has built up for substantial excess heat (far beyond ordinary chemical energy) and low-energy nuclear reaction phenomena in specialized heavy hydrogen and ordinary hydrogen-containing systems.1 The primary theorists in the field that is properly designated Cold Fusion/LENR have generally assumed that the excess heat phenomena is commensurate with nuclear ash (such as helium), whether already identified or presumed to be present but not yet found. That was an excellent initial hypothesis. However, the commensurate nuclear ash hypothesis has not been proved, and appears to be approximately correct in only a few experiments. During this same period, compelling evidence although not as broadly verified as data from cold fusion/LENR has also emerged for other microphysical sources of energy that were previously unexpected by accepted physics. The exemplar of this has been the "hydrino" physics work of Dr. Randall Mills and his colleagues at Black-Light Power Corporation, which was a radical outgrowth from the cold fusion field that emerged publicly in May 1991.2 Even more far-reaching is the work in vacuum energy extraction pioneered by Dr. Paulo and Alexandra Correa, which first became public in 1996.3 This vacuum energy experimentation began in the early 1980s and has been reduced to prototype technological devices, such as the patented PAGDTM (pulsed abnormal glow discharge) electric power generator, as well as many published experiments that can be performed in table-top fashion to verify the Correa Aetherometry (non-luminiferous or non-electromagnetic aether measurement science).4 In an era when mainstream science and its media is all agog about dark matter and dark energy composing the vast bulk of the universe, there is a great need to reconcile, if possible, the significant bodies of evidence from these three major experimental and theoretical streams: cold fusion/LENR, hydrino physics, and

  5. Purdue Contribution of Fusion Simulation Program

    SciTech Connect

    Jeffrey Brooks

    2011-09-30

    . It will address the origins and structure of the plasma electric field, rotation, the L-H transition, and the wide variety of pedestal relaxation mechanisms. The Whole Device Model will predict the entire discharge evolution given external actuators (i.e., magnets, power supplies, heating, current drive and fueling systems) and control strategies. Based on components operating over a range of physics fidelity, the WDM will model the plasma equilibrium, plasma sources, profile evolution, linear stability and nonlinear evolution toward a disruption (but not the full disruption dynamics). The plan assumes that, as the FSP matures and demonstrates success, the program will evolve and grow, enabling additional science problems to be addressed. The next set of integration opportunities could include: 1) Simulation of disruption dynamics and their effects; 2) Prediction of core profile including 3D effects, mesoscale dynamics and integration with the edge plasma; 3) Computation of non-thermal particle distributions, self-consistent with fusion, radio frequency (RF) and neutral beam injection (NBI) sources, magnetohydrodynamics (MHD) and short-wavelength turbulence.

  6. The Fusion Gain Analysis of the Inductively Driven Liner Compression Based Fusion

    NASA Astrophysics Data System (ADS)

    Shimazu, Akihisa; Slough, John

    2016-10-01

    An analytical analysis of the fusion gain expected in the inductively driven liner compression (IDLC) based fusion is conducted to identify the fusion gain scaling at various operating conditions. The fusion based on the IDLC is a magneto-inertial fusion concept, where a Field-Reversed Configuration (FRC) plasmoid is compressed via the inductively-driven metal liner to drive the FRC to fusion conditions. In the past, an approximate scaling law for the expected fusion gain for the IDLC based fusion was obtained under the key assumptions of (1) D-T fuel at 5-40 keV, (2) adiabatic scaling laws for the FRC dynamics, (3) FRC energy dominated by the pressure balance with the edge magnetic field at the peak compression, and (4) the liner dwell time being liner final diameter divided by the peak liner velocity. In this study, various assumptions made in the previous derivation is relaxed to study the change in the fusion gain scaling from the previous result of G ml1 / 2 El11 / 8 , where ml is the liner mass and El is the peak liner kinetic energy. The implication from the modified fusion gain scaling on the performance of the IDLC fusion reactor system is also explored.

  7. Establishment of an Institute for Fusion Studies

    SciTech Connect

    Hazeltine, R.D.

    1992-07-01

    The Institute for Fusion Studies is a national center for theoretical fusion plasma physics research. Its purposes are: (1) to conduct research on theoretical questions concerning the achievement of controlled fusion energy by means of magnetic confinement--including both fundamental problems of long-range significance, as well as shorter-term issues; (2) to serve as a center for information exchange, nationally and internationally, by hosting exchange visits, conferences, and workshops; (3) and to train students and postdoctoral research personnel for the fusion energy program and plasma physics research areas. The theoretical research results that are obtained by the Institute contribute mainly to the progress of national and international efforts in nuclear fusion research, whose goal is the development of fusion power.as a basic energy source. In addition to its primary focus on fusion physics, the Institute is also involved with research in related fields, such as advanced computing techniques, nonlinear dynamics, plasma astrophysics, and accelerator physics. The work of EFS scientists continued to receive national and international recognition. Numerous invited papers were given during the past year at workshops, conferences, and scientific meetings. Last year IFS scientists published 95 scientific articles in technical journals and monographs.

  8. Self-organized helical equilibria as a new paradigm for ohmically heated fusion plasmas

    NASA Astrophysics Data System (ADS)

    Lorenzini, R.; Martines, E.; Piovesan, P.; Terranova, D.; Zanca, P.; Zuin, M.; Alfier, A.; Bonfiglio, D.; Bonomo, F.; Canton, A.; Cappello, S.; Carraro, L.; Cavazzana, R.; Escande, D. F.; Fassina, A.; Franz, P.; Gobbin, M.; Innocente, P.; Marrelli, L.; Pasqualotto, R.; Puiatti, M. E.; Spolaore, M.; Valisa, M.; Vianello, N.; Martin, P.; Martin, P.; Apolloni, L.; Puiatti, M. E.; Adamek, J.; Agostini, M.; Alfier, A.; Annibaldi, S. V.; Antoni, V.; Auriemma, F.; Barana, O.; Baruzzo, M.; Bettini, P.; Bolzonella, T.; Bonfiglio, D.; Bonomo, F.; Brombin, M.; Brotankova, J.; Buffa, A.; Buratti, P.; Canton, A.; Cappello, S.; Carraro, L.; Cavazzana, R.; Cavinato, M.; Chapman, B. E.; Chitarin, G.; Dal Bello, S.; de Lorenzi, A.; de Masi, G.; Escande, D. F.; Fassina, A.; Ferro, A.; Franz, P.; Gaio, E.; Gazza, E.; Giudicotti, L.; Gnesotto, F.; Gobbin, M.; Grando, L.; Guazzotto, L.; Guo, S. C.; Igochine, V.; Innocente, P.; Liu, Y. Q.; Lorenzini, R.; Luchetta, A.; Manduchi, G.; Marchiori, G.; Marcuzzi, D.; Marrelli, L.; Martini, S.; Martines, E.; McCollam, K.; Milani, F.; Moresco, M.; Novello, L.; Ortolani, S.; Paccagnella, R.; Pasqualotto, R.; Peruzzo, S.; Piovan, R.; Piovesan, P.; Piron, L.; Pizzimenti, A.; Pomaro, N.; Predebon, I.; Reusch, J. A.; Rostagni, G.; Rubinacci, G.; Sarff, J. S.; Sattin, F.; Scarin, P.; Serianni, G.; Sonato, P.; Spada, E.; Soppelsa, A.; Spagnolo, S.; Spolaore, M.; Spizzo, G.; Taliercio, C.; Terranova, D.; Toigo, V.; Valisa, M.; Vianello, N.; Villone, F.; White, R. B.; Yadikin, D.; Zaccaria, P.; Zamengo, A.; Zanca, P.; Zaniol, B.; Zanotto, L.; Zilli, E.; Zohm, H.; Zuin, M.

    2009-08-01

    In the quest for new energy sources, the research on controlled thermonuclear fusion has been boosted by the start of the construction phase of the International Thermonuclear Experimental Reactor (ITER). ITER is based on the tokamak magnetic configuration, which is the best performing one in terms of energy confinement. Alternative concepts are however actively researched, which in the long term could be considered for a second generation of reactors. Here, we show results concerning one of these configurations, the reversed-field pinch (RFP). By increasing the plasma current, a spontaneous transition to a helical equilibrium occurs, with a change of magnetic topology. Partially conserved magnetic flux surfaces emerge within residual magnetic chaos, resulting in the onset of a transport barrier. This is a structural change and sheds new light on the potential of the RFP as the basis for a low-magnetic-field ohmic fusion reactor.

  9. Ballistic contributions to heat pulse propagation on TFTR (Tokamak Fusion Test Reactor)

    SciTech Connect

    Fredrickson, E.D.; McGuire, K.; Cavallo, A.; Budny, R.; Janos, A.; Monticello, D.; Nagayama, Y.; Park, W.; Taylor, G.; Zarnstorff, M.C.

    1990-07-01

    Measurements on the TFTR tokamak of the electron temperature profile evolution and soft x-ray emissivity on a fast (10 {mu}sec) time scale during a sawtooth crash, show that significant heat is deposited beyond the mixing (or reconnection) radius within 200 {mu}sec following a sawtooth crash. This extended region in which electron heat is redistributed during the sawtooth crash substantially complicates the determination of heat transport properties from the subsequent heat pulse propagation. It is shown that the relaxation of this extended perturbation is consistent with the power balance estimates of the local thermal diffusivity. 19 refs., 6 figs.

  10. Intermediates and kinetics of membrane fusion.

    PubMed Central

    Bentz, J

    1992-01-01

    Recently, it has become clear that the influenza virus fusion protein, hemagglutinin (HA), produces membrane destabilization and fusion by a multistep process, which involves the aggregation of the HAs to form a fusion site. While the details of this process are under debate, it is important to recognize that proposing any sequence of "microscopic" fusion intermediates encumbers general "macroscopic" kinetic consequences, i.e., with respect to membrane mixing rates. Using a kinetic scheme which incorporates the essential elements of several recently proposed models, some of these measurable properties have been elucidated. First, a rigorous mathematical relationship between fusion intermediates and the fusion event itself is defined. Second, it is shown that what is measured as the macroscopic "fusion rate constant" is a simple function of all of the rate constants governing the transitions between intermediates, whether or not one of the microscopic steps is rate limiting. Third, while this kinetic scheme predicts a delay (or lag) time for fusion, as has been observed, it will be very difficult to extract reliable microscopic information from these data. Furthermore, it is predicted that the delay time can depend upon HA surface density even when the HA aggregation step is very rapid compared with fusion, i.e., the delay time need not be due to HA aggregation. Fourth, the inactivation process observed for influenza virions at low pH can be described within this kinetic scheme simply, yet rigorously, via the loss of the fusion intermediates. Fifth, predicted Arrhenius plots of fusion rates can be linear for this multistep scheme, even though there is no single rate-determining step and even when a branched step is introduced, i.e., where one pathway predominates at low temperature and the other pathway predominates at high temperature. Furthermore, the apparent activation energies obtained from these plots bear little or no quantitative resemblance to the

  11. Energy dependence of fusion cross sections

    SciTech Connect

    Bang, J.M.; Ferreira, L.S.; Maglione, E.; Hansteen, J.M.

    1996-01-01

    Observed enhancements of fusion cross sections at low energies are explained as caused by an underestimate of beam energy due to an overestimate of the stopping energy loss. {copyright} {ital 1996 The American Physical Society.}

  12. Performance limits of fusion first-wall structural materials.

    SciTech Connect

    Smith, D. L.; Majumdar, S.; Billone, M.; Mattas, R. F.

    1999-11-12

    Key features of fusion energy relate primarily to potential advantages associated with safety and environmental considerations and the near endless supply of fuel. However, it is generally concluded that high performance fusion power systems will be required in order to be economically competitive with other energy options. As in most energy systems, structural materials operating limits pose a primary constraint to the performance of fusion power systems. It is also recognized that for the case of fusion power, the first-wall/blanket system will have a dominant impact on both the economic and safety/environmental attractiveness of fusion energy. The first-wall blanket structure is particularly critical since it must maintain high integrity at relatively high temperatures during exposure to high radiation levels, high surface heat fluxes, and significant primary stresses. The performance limits of the first-wall/blanket structure will be dependent on the structural material properties, the coolant/breeder system, and the specific design configuration. Key factors associated with high performance structural materials include (1) high temperature operation, (2) a large operating temperature window, and (3) a long operating lifetime. High temperature operation is necessary to provide for high power conversion efficiency. As discussed later, low-pressure coolant systems provide significant advantages. A large operating temperature window is necessary to accommodate high surface heating and high power density. The operating temperature range for the structure must include the temperature gradient through the first wall and the coolant system AT required for efficient energy conversion. This later requirement is dependent on the coolant/breeder operating temperature limits. A long operating lifetime of the structure is important to improve system availability and to minimize waste disposition.

  13. A burning plasma program strategy to advance fusion energy. Report of the Fusion Energy Sciences Advisory Committee, Burning Plasma Strategy Panel

    SciTech Connect

    None, None

    2002-09-01

    Fusion energy shows great promise to contribute to securing the energy future of humanity. The risk of conflicts arising from energy shortages and supply cutoffs, as well as the risk of severe environmental impacts from existing methods of energy production, are strong reasons to pursue fusion energy now. The world effort to develop fusion energy is at the threshold of a new stage in its research: the investigation of burning plasmas. This investigation, at the frontier of the physics of complex systems, would be a huge step in establishing the potential of magnetic fusion energy to contribute to the world’s energy security. The defining feature of a burning plasma is that it is self-heated: the 100 million degree temperature of the plasma is maintained mainly by the heat generated by the fusion reactions themselves, as occurs in burning stars. The fusion-generated alpha particles produce new physical phenomena that are strongly coupled together as a nonlinear complex system. Understanding all elements of this system poses a major challenge to fundamental plasma physics. The technology needed to produce and control a burning plasma presents challenges in engineering science similarly essential to the development of fusion energy.

  14. Fundamental studies of fusion plasmas. Final report

    SciTech Connect

    Aamodt, R.E.

    1998-01-30

    Lodestar has carried out a vigorous research program in the areas of rf, edge plasma and divertor physics, with emphasis largely geared towards improving the understanding and performance of ion-cyclotron heating and current drive (ICRF) systems. Additionally, a research program in the field of edge plasma and divertor modeling was initiated. Theoretical work on high power rf sheath formation for multi-strap rf arrays was developed and benchmarked against recent experimental data from the new JET A2 antennas. Sophisticated modeling tools were employed to understand the sheath formation taking into account realistic three-dimensional antenna geometry. A novel physics explanation of an observed anomaly in the low power loading of antennas was applied to qualitatively interpret data on DIII-D in terms of rf sheaths, and potential applications of the idea to develop a near-field sheath diagnostic were explored. Other rf-wave related topics were also investigated. Full wave ICRF modeling studies were carried out in support of ongoing and planned tokamaks experiments, including the investigation of low frequency plasma heating and current drive regimes for IGNITOR. In a cross-disciplinary study involving both MHD and ICRF physics, ponderomotive feedback stabilization by rf was investigated as a potential means of controlling external kink mode disruptions. In another study, the instability of the ion hybrid wave (IHW) in the presence of fusion alpha particles was studied. In the field of edge plasma and divertor modeling studies, Lodestar began the development of a theory of generalized ballooning and sheath instabilities in the scrape off layer (SOL) of divertor tokamaks. A detailed summary of the technical progress in these areas during the contract period is included, as well as where references to published work can be found. A separate listing of publications, meeting abstracts, and other presentations is also given at the end of this final report.

  15. [Fusion implants of carbon fiber reinforced plastic].

    PubMed

    Früh, H J; Liebetrau, A; Bertagnoli, R

    2002-05-01

    Carbon fiber reinforced plastics (CFRP) are used in the medical field when high mechanical strength, innovative design, and radiolucency (see spinal fusion implants) are needed. During the manufacturing process of the material CFRP carbon fibers are embedded into a resin matrix. This resin material could be thermoset (e.g., epoxy resin EPN/DDS) or thermoplastic (e.g., PEAK). CFRP is biocompatible, radiolucent, and has higher mechanical capabilities compared to other implant materials. This publication demonstrates the manufacturing process of fusion implants made of a thermoset matrix system using a fiber winding process. The material has been used clinically since 1994 for fusion implants of the cervical and lumbar spine. The results of the fusion systems CORNERSTONE-SR C (cervical) and UNION (lumbar) showed no implant-related complications. New implant systems made of this CFRP material are under investigation and are presented.

  16. Modes of paramyxovirus fusion: a Henipavirus perspective.

    PubMed

    Lee, Benhur; Ataman, Zeynep Akyol

    2011-08-01

    Henipavirus is a new genus of Paramyxoviridae that uses protein-based receptors (ephrinB2 and ephrinB3) for virus entry. Paramyxovirus entry requires the coordinated action of the fusion (F) and attachment viral envelope glycoproteins. Receptor binding to the attachment protein triggers F to undergo a conformational cascade that results in membrane fusion. The accumulation of structural and functional studies on many paramyxoviral fusion and attachment proteins, including the recent elucidation of structures of Nipah virus (NiV) and Hendra virus (HeV) G glycoproteins bound and unbound to cognate ephrinB receptors, indicate that henipavirus entry and fusion could differ mechanistically from paramyxoviruses that use glycan-based receptors.

  17. Mechanisms of tissue fusion during development

    PubMed Central

    Ray, Heather J.; Niswander, Lee

    2012-01-01

    Tissue fusion events during embryonic development are crucial for the correct formation and function of many organs and tissues, including the heart, neural tube, eyes, face and body wall. During tissue fusion, two opposing tissue components approach one another and integrate to form a continuous tissue; disruption of this process leads to a variety of human birth defects. Genetic studies, together with recent advances in the ability to culture developing tissues, have greatly enriched our knowledge of the mechanisms involved in tissue fusion. This review aims to bring together what is currently known about tissue fusion in several developing mammalian organs and highlights some of the questions that remain to be addressed. PMID:22510983

  18. Bibliography of fusion product physics in tokamaks

    SciTech Connect

    Hively, L. M.; Sigmar, D. J.

    1989-09-01

    Almost 700 citations have been compiled as the first step in reviewing the recent research on tokamak fusion product effects in tokamaks. The publications are listed alphabetically by the last name of the first author and by subject category.

  19. Computational mathematics and physics of fusion reactors

    PubMed Central

    Garabedian, Paul R.

    2003-01-01

    Theory has contributed significantly to recent advances in magnetic fusion research. New configurations have been found for a stellarator experiment by computational methods. Solutions of a free-boundary problem are applied to study the performance of the plasma and look for islands in the magnetic surfaces. Mathematical analysis and numerical calculations have been used to study equilibrium, stability, and transport of optimized fusion reactors. PMID:14614129

  20. [Mechanical studies of lumbar interbody fusion implants].

    PubMed

    Bader, R J; Steinhauser, E; Rechl, H; Mittelmeier, W; Bertagnoli, R; Gradinger, R

    2002-05-01

    In addition to autogenous or allogeneic bone grafts, fusion cages composed of metal or plastic are being used increasingly as spacers for interbody fusion of spinal segments. The goal of this study was the mechanical testing of carbon fiber reinforced plastic (CFRP) fusion cages used for anterior lumbar interbody fusion. With a special testing device according to American Society for Testing and Materials (ASTM) standards, the mechanical properties of the implants were determined under four different loading conditions. The implants (UNION cages, Medtronic Sofamor Danek) provide sufficient axial compression, shear, and torsional strength of the implant body. Ultimate axial compression load of the fins is less than the physiological compression loads at the lumbar spine. Therefore by means of an appropriate surgical technique parallel grooves have to be reamed into the endplates of the vertebral bodies according to the fin geometry. Thereby axial compression forces affect the implants body and the fins are protected from damaging loading. Using a supplementary anterior or posterior instrumentation, in vivo failure of the fins as a result of physiological shear and torsional spinal loads is unlikely. Due to specific complications related to autogenous or allogeneic bone grafts, fusion cages made of metal or carbon fiber reinforced plastic are an important alternative implant in interbody fusion.

  1. Enhancement of viral fusion by nonadsorbing polymers.

    PubMed Central

    Herrmann, A; Clague, M J; Blumenthal, R

    1993-01-01

    Nonadsorbing polymers such as dextran and poly(ethylene glycol) enhance binding as well as extents of fusion of influenza virus with erythrocytes. Kinetics and extent of viral membrane fusion were measured using an assay based on lipid mixing of a fluorescent dye. The effects of nonadsorbing polymers were in the concentration range from 0 to 10 wt%, far below the concentration required to overcome hydration repulsion forces. The enhancing effects were dependent on the molecular weight of nonadsorbing polymer, and only occurred at molecular weight > 1500; this links the phenomena we observe to the so-called "excluded volume effect" of nonadsorbing polymers. The time delay between triggering and the onset of influenza virus fusion was significantly reduced in the presence of nonadsorbing polymers. High molecular weight poly(ethylene glycol) also induced fusion of vesicular stomatitis virus with intact erythrocytes, which do not serve as target of vesicular stomatitis virus fusion in the absence of the polymer. The forces between membranes which determine rate-limiting processes in viral fusion and how they are affected by nonadsorbing polymers are discussed. PMID:7690263

  2. Information Fusion of Conflicting Input Data

    PubMed Central

    Mönks, Uwe; Dörksen, Helene; Lohweg, Volker; Hübner, Michael

    2016-01-01

    Sensors, and also actuators or external sources such as databases, serve as data sources in order to realise condition monitoring of industrial applications or the acquisition of characteristic parameters like production speed or reject rate. Modern facilities create such a large amount of complex data that a machine operator is unable to comprehend and process the information contained in the data. Thus, information fusion mechanisms gain increasing importance. Besides the management of large amounts of data, further challenges towards the fusion algorithms arise from epistemic uncertainties (incomplete knowledge) in the input signals as well as conflicts between them. These aspects must be considered during information processing to obtain reliable results, which are in accordance with the real world. The analysis of the scientific state of the art shows that current solutions fulfil said requirements at most only partly. This article proposes the multilayered information fusion system MACRO (multilayer attribute-based conflict-reducing observation) employing the μBalTLCS (fuzzified balanced two-layer conflict solving) fusion algorithm to reduce the impact of conflicts on the fusion result. The performance of the contribution is shown by its evaluation in the scope of a machine condition monitoring application under laboratory conditions. Here, the MACRO system yields the best results compared to state-of-the-art fusion mechanisms. The utilised data is published and freely accessible. PMID:27801874

  3. Information Fusion of Conflicting Input Data.

    PubMed

    Mönks, Uwe; Dörksen, Helene; Lohweg, Volker; Hübner, Michael

    2016-10-29

    Sensors, and also actuators or external sources such as databases, serve as data sources in order to realise condition monitoring of industrial applications or the acquisition of characteristic parameters like production speed or reject rate. Modern facilities create such a large amount of complex data that a machine operator is unable to comprehend and process the information contained in the data. Thus, information fusion mechanisms gain increasing importance. Besides the management of large amounts of data, further challenges towards the fusion algorithms arise from epistemic uncertainties (incomplete knowledge) in the input signals as well as conflicts between them. These aspects must be considered during information processing to obtain reliable results, which are in accordance with the real world. The analysis of the scientific state of the art shows that current solutions fulfil said requirements at most only partly. This article proposes the multilayered information fusion system MACRO (multilayer attribute-based conflict-reducing observation) employing the μBalTLCS (fuzzified balanced two-layer conflict solving) fusion algorithm to reduce the impact of conflicts on the fusion result. The performance of the contribution is shown by its evaluation in the scope of a machine condition monitoring application under laboratory conditions. Here, the MACRO system yields the best results compared to state-of-the-art fusion mechanisms. The utilised data is published and freely accessible.

  4. Simulation of National Intelligence Process with Fusion

    DTIC Science & Technology

    2008-03-01

    modelled as zero mean Gaussian noise. The state estimate provided by a Kalman filter is statistically optimal in that it minimizes the mean squared error...the fusion methods above contain logical and mathematical algorithms based on either continuous or discrete quantifiable data, so to use these methods...method for capturing statistics about the performance of different architectures, it fails to capture the synergy of intelligence or information fusion

  5. Symbolic fusion of MMW and IR imagery

    NASA Astrophysics Data System (ADS)

    Eggleston, Peter A.; Kohl, Charles A.

    1988-01-01

    This paper describes the software architecture used to construct a multisensor knowledge-based Autonomous Target Recognizer (ATR). An Intermediate Symbolic Representation (SR) of processed data is employed to provide a very powerful method of associative access over data events and their features, thereby supporting data fusion algorithms at the symbolic level. This architecture supports data fusion from multiple sensors, and its operation is described here using MMW range and IR intensity data.

  6. Symbolic Fusion Of MMW And IR Imagery

    NASA Astrophysics Data System (ADS)

    Eggleston, Peter A.; Kohl, Charles A.

    1989-01-01

    This paper describes the software architecture used to construct a multi-sensor knowledge-based Autonomous Target Recognizer (ATR). An Intermediate Symbolic Representation (ISR) of processed data is employed to provide a very powerful method of associative access over data events and their features, thereby supporting data fusion algorithms at the symbolic level. This architecture supports data fusion from multiple sensors, and its operation is described here using MMW range and IR intensity data.

  7. Reactor applications of the Compact Fusion Advanced Rankine (CFAR) cycle for a D-T tokamak fusion reactor

    NASA Astrophysics Data System (ADS)

    Hoffman, H. A.; Logan, B. G.; Campbell, R. B.

    1988-03-01

    A preliminary design of a D-T fusion reactor blanket and MHD power conversion system is made based on the CFAR concept, and it was found that performance and costs for the reference cycle are very attractive. While much remains to be done, the potential advantage of liquid metal Rankine cycles for fusion applications are much clearer now. These include low pressures and mass flow rates, a nearly isothermal module shell which minimizes problems of thermal distortion and stresses, and an insensitivity to pressure losses in the blanket so that the two-phase MHD pressure drops in the boiling part of the blanket and the ordinary vapor pressure drops in the pebble-bed superheating zones are acceptable (the direct result of pumping a liquid rather than having to compress a gas). There are no moving parts in the high-temperature MHD power generators, no steam bottoming plant is required, only small vapor precoolers and condensers are needed because of the high heat rejection temperatures, and only a relatively small natural-draft heat exchanger is required to reject the heat to the atmosphere. The net result is a very compact fusion reactor and power conversion system which fit entirely inside an 18 meter radius reactor vault. Although a cost analysis has not yet been performed, preliminary cost estimates indicate low capital costs and a very attractive cost of electricity.

  8. Reply to "Comment on papers by K. Shanahan that propose to explain anomalous heat generated by cold fusion", E. Storms, Thermochim. Acta (2005)

    SciTech Connect

    Shanahan, Kirk

    2005-09-21

    Dr. E. Storms has published a Letter [1] in which he argues that in a sequence of recent papers [2-5], the apparent excess heat signal claimed by Dr. Shanahan to arise from a calibration constant shift is actually true excess heat. In particular he proposes that the mechanisms proposed that foster the proposed calibration constant shifts [3,5] cannot occur as postulated for several reasons. As well, he proposes Shanahan has ignored the extant data proving this. Because this Letter may lend unwarranted support to acceptance of cold fusion claims, these erroneous arguments used by Storms need to be answered.

  9. Neutron diffraction studies of viral fusion peptides

    NASA Astrophysics Data System (ADS)

    Bradshaw, Jeremy P.; J. M. Darkes, Malcolm; Katsaras, John; Epand, Richard M.

    2000-03-01

    Membrane fusion plays a vital role in a large and diverse number of essential biological processes. Despite this fact, the precise molecular events that occur during fusion are still not known. We are currently engaged on a study of membrane fusion as mediated by viral fusion peptides. These peptides are the N-terminal regions of certain viral envelope proteins that mediate the process of fusion between the viral envelope and the membranes of the host cell during the infection process. As part of this study, we have carried out neutron diffraction measurements at the ILL, BeNSC and Chalk River, on a range of viral fusion peptides. The peptides, from simian immunodeficiency virus (SIV), influenza A and feline leukaemia virus (FeLV), were incorporated into stacked phospholipid bilayers. Some of the peptides had been specifically deuterated at key amino acids. Lamellar diffraction data were collected and analysed to yield information on the peptide conformation, location and orientation relative to the bilayer.

  10. Moments of fusion-barrier distributions

    NASA Astrophysics Data System (ADS)

    Rehm, K. E.; Esbensen, H.; Jiang, C. L.; Back, B. B.; Stefanini, A. M.; Montagnoli, G.

    2016-10-01

    A study of fusion-barrier distributions through an analysis of their moments is presented. The moments can be obtained from least-squares fits of the energy-weighted fusion cross sections without the need of calculating second derivatives. The zeroth and first moments determine the fusion radius R and the Coulomb barrier VC. These two quantities are the same as the parameters R and VC that are used in the well-known expression, E σ =π R2(E -VC) , for the fusion cross section at high energies. The second and third moments, M2 and M3, determine the width and skewness of the barrier distribution, respectively. From these global parameters new correlations for the study of heavy-ion-induced fusion reactions can be obtained. Systems exhibiting a large coupling to transfer reactions show a small fusion radius as well as a large second moment. A negative third moment is correlated with a prolate deformation of the target nucleus.

  11. Ubiquitin fusion technology: bioprocessing of peptides.

    PubMed

    Pilon, A; Yost, P; Chase, T E; Lohnas, G; Burkett, T; Roberts, S; Bentley, W E

    1997-01-01

    Ubiquitin fusion technology represents an emerging method for economically producing peptides and small proteins in the bacterium Escherichia coli. Our focus is on peptide production where the need for cost-effective, scaleable processes has recently been highlighted by Kelley (1996). There are two principal features: (1) the expression system consists of a suitable E. coli host strain paired with a plasmid that encodes the ubiquitin fusion and (2) an ubiquitin-specific protease, UCH-L3, which cleaves only C-terminal extensions from ubiquitin. In this work, multigram yields were obtained of four ubiquitin fusions derived from cell paste generated in single 10-L fermentations. All were expressed intracellularly and remained soluble at extremely high levels of expression. Bacterial freeze--thaw lysates contained over 95% pure ubiquitin fusion protein. All four fusions were efficiently cleaved to ubiquitin and the peptide products. In one case, the final yield of peptide was 1.08 g from 3 L of low cell density bacterial culture. The combination of exceptional overexpression of the ubiquitin--peptide fusion proteins and a robust and specific protease are unique advantages contributing to a cost-effective, scaleable, and generic bioprocess for peptide production.

  12. Safety of magnetic fusion facilities: Requirements

    SciTech Connect

    1996-05-01

    This Standard identifies safety requirements for magnetic fusion facilities. Safety functions are used to define outcomes that must be achieved to ensure that exposures to radiation, hazardous materials, or other hazards are maintained within acceptable limits. Requirements applicable to magnetic fusion facilities have been derived from Federal law, policy, and other documents. In addition to specific safety requirements, broad direction is given in the form of safety principles that are to be implemented and within which safety can be achieved.

  13. Fusion of Images from Dissimilar Sensor Systems

    DTIC Science & Technology

    2004-12-01

    based fusion concepts and presents results demonstrating the robustness of the approach. Final remarks are provided in Chapter V. 3 II. BACKGROUND A...multiresolution analysis” methods. Image fusion by the statistical and numerical approach utilizes methods such as Principal Component Analysis ( PCA ) and...represent the pixel intensities in LWIR and MWIR sensors respectively. They are statistically decomposed using PCA into orthogonal components L1’ and

  14. Safety of magnetic fusion facilities: Guidance

    SciTech Connect

    1996-05-01

    This document provides guidance for the implementation of the requirements identified in DOE-STD-6002-96, Safety of Magnetic Fusion Facilities: Requirements. This guidance is intended for the managers, designers, operators, and other personnel with safety responsibilities for facilities designated as magnetic fusion facilities. While the requirements in DOE-STD-6002-96 are generally applicable to a wide range of fusion facilities, this Standard, DOE-STD-6003-96, is concerned mainly with the implementation of those requirements in large facilities such as the International Thermonuclear Experimental Reactor (ITER). Using a risk-based prioritization, the concepts presented here may also be applied to other magnetic fusion facilities. This Standard is oriented toward regulation in the Department of Energy (DOE) environment as opposed to regulation by other regulatory agencies. As the need for guidance involving other types of fusion facilities or other regulatory environments emerges, additional guidance volumes should be prepared. The concepts, processes, and recommendations set forth here are for guidance only. They will contribute to safety at magnetic fusion facilities.

  15. Score Fusion and Decision Fusion for the Performance Improvement of Face Recognition

    DTIC Science & Technology

    2013-07-01

    a face recognition system, we propose a fusion solution consisting of score fusion of multispectral images and decision fusion of stereo images...Univ. MultiSpectral Stereo face dataset that currently consists of the stereo face images of two spectral bands from 105 subjects. The experimental... consists of two stereo imaging cameras (Left and Right). Each side has two spectral bands, visible and thermal. The face scores from multiple matchers are

  16. Concept of DT fuel cycle for a fusion neutron source

    SciTech Connect

    Anan'ev, S.; Spitsyn, A.V.; Kuteev, B.V.; Cherkez, D.I.; Shirnin, P.N.; Kazakovsky, N.T.

    2015-03-15

    A concept of DT-fusion neutron source (FNS) with the neutron yield higher than 10{sup 18} neutrons per second is under design in Russia. Such a FNS is of interest for many applications: 1) basic and applied research (neutron scattering, etc); 2) testing the structural materials for fusion reactors; 3) control of sub-critical nuclear systems and 4) nuclear waste processing (including transmutation of minor actinides). This paper describes the fuel cycle concept of a compact fusion neutron source based on a small spherical tokamak (FNS-ST) with a MW range of DT fusion power and considers the key physics issues of this device. The major and minor radii are ∼0.5 and ∼0.3 m, magnetic field ∼1.5 T, heating power less than 15 MW and plasma current 1-2 MA. The system provides the fuel mixture with equal fractions of D and T (D:T = 1:1) for all FNS technology systems. (authors)

  17. Computational and experimental investigation of magnetized target fusion

    SciTech Connect

    Sheehey, P.T.; Guzik, J.A.; Kirkpatrick, R.C.; Lindemuth, I.R.; Scudder, D.W.; Shlachter, J.S.; Wysocki, F.J.

    1996-07-01

    In Magnetized Target Fusion (MTF), a preheated and magnetized target plasma is hydrodynamically compressed to fusion conditions. Because the magnetic field suppresses losses by electron thermal conduction in the fuel during the target implosion heating process, the compression may be over a much longer time scale than in traditional inertial confinement fusion (ICF). Bigger targets and much lower initial target densities than in ICF can be used, reducing radiative energy losses. Therefore, ``liner-on-plasma`` compressions, driven by relatively inexpensive electrical pulsed power, may be practical. Potential MTF target plasmas must meet minimum temperature, density, and magnetic field starting conditions, and must remain relatively free of high-Z radiation-cooling-enhancing contaminants. At Los Alamos National Laboratory, computational and experimental research is being pursued into MTF target plasmas, such as deuterium-fiber-initiated Z-pinches, and the Russian-originated MAGO plasma. In addition, liner-on-plasma compressions of such target plasmas to fusion conditions are being computationally modeled, and experimental investigation of such heavy liner implosions has begun. The status of the research will be presented.

  18. Plasma-Materials Interactions (PMI) and High-Heat-Flux (HHF) component research and development in the US Fusion Program

    SciTech Connect

    Conn, R.W.

    1986-10-01

    Plasma particle and high heat fluxes to in-vessel components such as divertors, limiters, RF launchers, halo plasma scrapers, direct converters, and wall armor, and to the vacuum chamber itself, represent central technical issues for fusion experiments and reactors. This is well recognized and accepted. It is also well recognized that the conditions at the plasma boundary can directly influence core plasma confinement. This has been seen most dramatically, on the positive side, in the discovery of the H-mode using divertors in tokamaks. It is also reflected in the attention devoted worldwide to the problems of impurity control. Nowadays, impurities are controlled by wall conditioning, special discharge cleaning techniques, special coatings such as carbonization, the use of low-Z materials for limiters and armor, a careful tailoring of heat loads, and in some machines, through the use of divertors. All programs, all experiments, and all designers are now keenly aware that PMI and HHF issues are key to the successful performance of their machines. In this brief report we present general issues in Section 2, critical issues in Section 3, existing US PMI/HHF experiments and facilities in Section 4, US International Cooperative PMI/HHF activities in Section 5, and conclude with a discussion on major tasks in PMI/HHF in Section 6.

  19. Recent magneto-inertial fusion experiments on the field reversed configuration heating experiment

    NASA Astrophysics Data System (ADS)

    Degnan, J. H.; Amdahl, D. J.; Domonkos, M.; Lehr, F. M.; Grabowski, C.; Robinson, P. R.; Ruden, E. L.; White, W. M.; Wurden, G. A.; Intrator, T. P.; Sears, J.; Weber, T.; Waganaar, W. J.; Frese, M. H.; Frese, S. D.; Camacho, J. F.; Coffey, S. K.; Makhin, V.; Roderick, N. F.; Gale, D. G.; Kostora, M.; Lerma, A.; McCullough, J. L.; Sommars, W.; Kiuttu, G. F.; Bauer, B.; Fuelling, S. R.; Siemon, R. E.; Lynn, A. G.; Turchi, P. J.

    2013-09-01

    Magneto-inertial fusion (MIF) approaches take advantage of an embedded magnetic field to improve plasma energy confinement by reducing thermal conduction relative to conventional inertial confinement fusion (ICF). MIF reduces required precision in the implosion and the convergence ratio. Since 2008 (Wurden et al 2008 IAEA 2008 Fusion Energy Conf. (Geneva, Switzerland, 13-18 October) IC/P4-13 LA-UR-08-0796) and since our prior refereed publication on this topic (Degnan et al 2008 IEEE Trans. Plasma Sci. 36 80), AFRL and LANL have developed further one version of MIF. We have (1) reliably formed, translated, and captured field reversed configurations (FRCs) in magnetic mirrors inside metal shells or liners in preparation for subsequent compression by liner implosion; (2) imploded a liner with interior magnetic mirror field, obtaining evidence for compression of a 1.36 T field to 540 T (3) performed a full system experiment of FRC formation, translation, capture, and imploding liner compression operation; (4) identified by comparison of 2D-MHD simulation and experiments factors limiting the closed-field lifetime of FRCs to about half that required for good liner compression of FRCs to multi-keV, 1019 ion cm-3, high energy density plasma (HEDP) conditions; and (5) designed and prepared hardware to increase that closed-field FRC lifetime to the required amount. Those lifetime experiments are now underway, with the goal of at least doubling closed-field FRC lifetimes and performing FRC implosions to HEDP conditions this year. These experiments have obtained imaging evidence of FRC rotation, and of initial rotation control measures slowing and stopping such rotation. Important improvements in fidelity of simulation to experiment have been achieved, enabling improved guidance and understanding of experiment design and performance.

  20. Fission-detector determination of D-D triton burnup fraction in beam-heated TFTR (Tokamak Fusion Test Reactor) plasmas

    SciTech Connect

    Jassby, D.L.; Hendel, H.W.; Barnes, C.W.; Bosch, S.; Cecil, F.E.; McCune, D.C.; Nieschmidt, E.B.; Strachan, J.D.

    1987-06-01

    After the end of a neutral-beam injection pulse into a low-density TFTR plasma, once the beam-injected deuterons have thermalized, the neutron emission is dominated by the 14-MeV neutron production from D-D triton burnup. Ordinary fission detectors can measure the 14-MeV emission rate, which can be extrapolated back in time to estimate the equilibrium triton burnup fraction. The fractional burnup determined by this method is in the range of 0.3 to 1.5% for TFTR discharges to date, and is consistent with classical confinement and slowing down. 10 refs., 3 figs.

  1. Dynamical Safety Analysis of the SABR Fusion-Fission Hybrid Reactor

    NASA Astrophysics Data System (ADS)

    Sumner, Tyler; Stacey, Weston; Ghiaassian, Seyed

    2009-11-01

    A hybrid fusion-fission reactor for the transmutation of spent nuclear fuel is being developed at Georgia Tech. The Subcritical Advanced Burner Reactor (SABR) is a 3000 MWth sodium-cooled, metal TRU-Zr fueled fast reactor driven by a tokamak fusion neutron source based on ITER physics and technology. We are investigating the accident dynamics of SABR's coupled fission, fusion and heat removal systems to explore the safety characteristics of a hybrid reactor. Possible accident scenarios such as loss of coolant mass flow (LOFA), of power (LOPA) and of heat sink (LOHSA), as well as inadvertent reactivity insertions and fusion source excursion are being analyzed using the RELAP5-3D code, the ATHENA version of which includes liquid metal coolants.

  2. A Tripartite Fusion, FaeG-FedF-LT192A2:B, of Enterotoxigenic Escherichia coli (ETEC) Elicits Antibodies That Neutralize Cholera Toxin, Inhibit Adherence of K88 (F4) and F18 Fimbriae, and Protect Pigs against K88ac/Heat-Labile Toxin Infection ▿

    PubMed Central

    Ruan, Xiaosai; Liu, Mei; Casey, Thomas A.; Zhang, Weiping

    2011-01-01

    Enterotoxigenic Escherichia coli (ETEC) strains expressing K88 (F4) or F18 fimbriae and heat-labile (LT) and/or heat-stable (ST) toxins are the major cause of diarrhea in young pigs. Effective vaccines inducing antiadhesin (anti-K88 and anti-F18) and antitoxin (anti-LT and anti-ST) immunity would provide broad protection to young pigs against ETEC. In this study, we genetically fused nucleotides coding for peptides from K88ac major subunit FaeG, F18 minor subunit FedF, and LT toxoid (LT192) A2 and B subunits for a tripartite adhesin-adhesin-toxoid fusion (FaeG-FedF-LT192A2:B). This fusion was used for immunizations in mice and pigs to assess the induction of antiadhesin and antitoxin antibodies. In addition, protection by the elicited antiadhesin and antitoxin antibodies against a porcine ETEC strain was evaluated in a gnotobiotic piglet challenge model. The data showed that this FaeG-FedF-LT192A2:B fusion elicited anti-K88, anti-F18, and anti-LT antibodies in immunized mice and pigs. In addition, the anti-porcine antibodies elicited neutralized cholera toxin and inhibited adherence against both K88 and F18 fimbriae. Moreover, immunized piglets were protected when challenged with ETEC strain 30302 (K88ac/LT/STb) and did not develop clinical disease. In contrast, all control nonvaccinated piglets developed severe diarrhea and dehydration after being challenged with the same ETEC strain. This study clearly demonstrated that this FaeG-FedF-LT192A2:B fusion antigen elicited antibodies that neutralized LT toxin and inhibited the adherence of K88 and F18 fimbrial E. coli strains and that this fusion could serve as an antigen for vaccines against porcine ETEC diarrhea. In addition, the adhesin-toxoid fusion approach used in this study may provide important information for developing effective vaccines against human ETEC diarrhea. PMID:21813665

  3. Ultrahigh heat flux plasma-facing components for magnetic fusion energy

    SciTech Connect

    Youchison, D. L.

    2012-03-01

    Sandia and Ultramet partnered to design and test refractory metal plasma-facing components and heat exchangers for advanced, high-temperature power conversion systems. These devices consisted of high-temperature helium-to-helium and lithium-to-helium heat exchangers that operate with high efficiency due to the porous foam inserts used in the gas stream, which promote turbulence and provide extended surface area for enhanced convection. Single- and multi-channel helium panels and the Li-He heat exchanger were fabricated from either pure molybdenum, TZM, or tungsten. The design was carried out through an Ultramet subcontractor. The flow path was carefully tailored to minimize the pressure drop while maximizing the heat transfer. The single- and multi-channel helium panels were tested at Sandia's PMTF using an electron beam system and the closed helium flow loop. In 2006, a single-channel tungsten tube was successfully tested to an average heat flux of 14 MW/m{sup 2} with a localized peak of 22 MW/m{sup 2} along the axial centerline at the outer radius. Under this CRADA, multiple square-channel molybdenum components were successfully tested to heat flux levels approaching 8.5 MW/m{sup 2}. The three multi-channel prototypes experienced mechanical failure due to issues related to the design of the large unsupported span of the heated faceplates in combination with prototype material and braze selection. The Li-He heat exchanger was both designed and partially tested at the PMTF for helium and lithium flow.

  4. Neutral particle measurements of fusion tritons in JET

    SciTech Connect

    Afanasyev, V. I.; Khudoleev, A. V.

    2010-08-15

    A neutral particle analyzer [A.D. Izvozchikov et al., JET Report No. JET-R(91)-12, 1991] operating in the MeV energy range was used to measure the flux of neutralized d-d fusion tritons emitted from the hot-ion H-mode deuterium plasma heated by deuterium neutral beams. It was found that tritons in the energy range of 0.3-1.1 MeV were largely neutralized by the beam atoms and the beam halo atoms. This enabled us to find the localized energy distribution function of the fusion tritons in the central plasma region. Simulation of the triton energy distribution function shows that MeV ions in the JET hot-ion H-mode plasma behave classically.

  5. Fusion plasma theory. Task 3: Auxiliary heating in Tokamaks and tandem mirrors

    NASA Astrophysics Data System (ADS)

    Scharer, J. E.

    1984-06-01

    The ICRF coupling, heating and breakeven studies for Tokamaks and ECRF fundamental second harmonic heating in tandem mirrors are examined. The studies have included ICRF Fokker-Planck heating and breakeven studies for large Tokamaks such as JET, fundamental work on a new wave power absorption and conservation relation for ICRF in inhomogeneous plasmas, a formulation and code development for ICRF waveguide coupling in Tokamak edge regions. The ECRF ray tracing studies were carried out for fundamental and second harmonic propagation, absorption and whistler microinstabilities in tandem mirror plug and barrier regions of Phaedrus, TMX-U and TASKA. The two-dimensional velocity space, time dependent Fokker-Planck heating studies have concentrated on D-T breakeven scenarios for fundamental minority deuterium and second harmonic tritium regimes.

  6. Review of the Inertial Fusion Energy Program

    SciTech Connect

    none,

    2004-03-29

    Igniting fusion fuel in the laboratory remains an alluring goal for two reasons: the desire to study matter under the extreme conditions needed for fusion burn, and the potential of harnessing the energy released as an attractive energy source for mankind. The inertial confinement approach to fusion involves rapidly compressing a tiny spherical capsule of fuel, initially a few millimeters in radius, to densities and temperatures higher than those in the core of the sun. The ignited plasma is confined solely by its own inertia long enough for a significant fraction of the fuel to burn before the plasma expands, cools down and the fusion reactions are quenched. The potential of this confinement approach as an attractive energy source is being studied in the Inertial Fusion Energy (IFE) program, which is the subject of this report. A complex set of interrelated requirements for IFE has motivated the study of novel potential solutions. Three types of “drivers” for fuel compression are presently studied: high-averagepower lasers (HAPL), heavy-ion (HI) accelerators, and Z-Pinches. The three main approaches to IFE are based on these drivers, along with the specific type of target (which contains the fuel capsule) and chamber that appear most promising for a particular driver.

  7. Development of our laser fusion integration simulation

    NASA Astrophysics Data System (ADS)

    Li, Jinghong; Zhai, Chuanlei; Li, Shuanggui; Li, Xin; Zheng, Wudi; Yong, Heng; Zeng, Qinghong; Hang, Xudeng; Qi, Jin; Yang, Rong; Cheng, Juan; Song, Peng; Gu, Peijun; Zhang, Aiqing; An, Hengbin; Xu, Xiaowen; Guo, Hong; Cao, Xiaolin; Mo, Zeyao; Pei, Wenbing; Jiang, Song; Zhu, Shao-ping

    2013-11-01

    In the target design of the Inertial Confinement Fusion (ICF) program, it is common practice to apply radiation hydrodynamics code to study the key physical processes happening in ICF process, such as hohlraum physics, radiation drive symmetry, capsule implosion physics in the radiation-drive approach of ICF. Recently, many efforts have been done to develop our 2D integrated simulation capability of laser fusion with a variety of optional physical models and numerical methods. In order to effectively integrate the existing codes and to facilitate the development of new codes, we are developing an object-oriented structured-mesh parallel code-supporting infrastructure, called JASMIN. Based on two-dimensional three-temperature hohlraum physics code LARED-H and two-dimensional multi-group radiative transfer code LARED-R, we develop a new generation two-dimensional laser fusion code under the JASMIN infrastructure, which enable us to simulate the whole process of laser fusion from the laser beams' entrance into the hohlraum to the end of implosion. In this paper, we will give a brief description of our new-generation two-dimensional laser fusion code, named LARED-Integration, especially in its physical models, and present some simulation results of holhraum.

  8. Information Fusion via the Wasserstein Barycenter in the Space of Probability Measures: Direct Fusion of Empirical Measures and Gaussian Fusion with Unknown Correlation

    DTIC Science & Technology

    2014-07-14

    metric captures the error in the expected value of a class of functions due to the approximation of one measure by another [22]. Thus, the fusion...result can be viewed as a measure with an expected value (for a class of function) that is minimally different (simultaneously) from the same expectation...Information Fusion via the Wasserstein Barycenter in the Space of Probability Measures : Direct Fusion of Empirical Measures and Gaussian Fusion with

  9. New applications of Spectral Edge image fusion

    NASA Astrophysics Data System (ADS)

    Hayes, Alex E.; Montagna, Roberto; Finlayson, Graham D.

    2016-05-01

    In this paper, we present new applications of the Spectral Edge image fusion method. The Spectral Edge image fusion algorithm creates a result which combines details from any number of multispectral input images with natural color information from a visible spectrum image. Spectral Edge image fusion is a derivative-based technique, which creates an output fused image with gradients which are an ideal combination of those of the multispectral input images and the input visible color image. This produces both maximum detail and natural colors. We present two new applications of Spectral Edge image fusion. Firstly, we fuse RGB-NIR information from a sensor with a modified Bayer pattern, which captures visible and near-infrared image information on a single CCD. We also present an example of RGB-thermal image fusion, using a thermal camera attached to a smartphone, which captures both visible and low-resolution thermal images. These new results may be useful for computational photography and surveillance applications.

  10. Methods of evaluating lumbar and cervical fusion.

    PubMed

    Gruskay, Jordan A; Webb, Matthew L; Grauer, Jonathan N

    2014-03-01

    Introduced in 1911, spinal fusion is now widely used to stabilize the cervical, thoracic, and lumbar spine. Despite advancements in surgical techniques, including the use of instrumentation and optimizing bone graft options, pseudarthrosis remains one of the most significant causes of clinical failure following attempted fusion. Diagnosis of this common complication is based on a focused clinical assessment and imaging studies. Pseudarthrosis classically presents with the onset of or return of axial or radicular symptoms during the first postoperative year. However, this diagnosis is complicated because other diagnoses can mimic these symptoms (such as infection or adjacent segment degeneration) and because many cases of pseudarthrosis are asymptomatic. Computed tomography and assessment of motion on flexion/extension radiographs are the two preferred imaging modalities for establishing the diagnosis of pseudarthrosis. The purpose of this article was to review the current status of imaging and clinical practices for assessing fusion following spinal arthrodesis.

  11. Midterm Summary of Japan-US Fusion Cooperation Program TITAN

    SciTech Connect

    Muroga, Takeo; Sze, Dai-Kai; Sokolov, Mikhail; Katoh, Yutai; Stoller, Roger E

    2011-01-01

    Japan-US cooperation program TITAN (Tritium, Irradiation and Thermofluid for America and Nippon) started in April 2007 as 6-year project. This is the summary report at the midterm of the project. Historical overview of the Japan-US cooperation programs and direction of the TITAN project in its second half are presented in addition to the technical highlights. Blankets are component systems whose principal functions are extraction of heat and tritium. Thus it is crucial to clarify the potentiality for controlling heat and tritium flow throughout the first wall, blanket and out-of-vessel recovery systems. The TITAN project continues the JUPITER-II activity but extends its scope including the first wall and the recovery systems with the title of 'Tritium and thermofluid control for magnetic and inertial confinement systems'. The objective of the program is to clarify the mechanisms of tritium and heat transfer throughout the first-wall, the blanket and the heat/tritium recovery systems under specific conditions to fusion such as irradiation, high heat flux, circulation and high magnetic fields. Based on integrated models, the breeding, transfer, inventory of tritium and heat extraction properties will be evaluated for some representative liquid breeder blankets and the necessary database will be obtained for focused research in the future.

  12. Some implications for mirror research of the coupling between fusion economics and fusion physics

    SciTech Connect

    Post, R.F.

    1980-01-01

    The thesis is made that physics understanding and innovation represent two of the most important ingredients of any program to develop fusion power. In this context the coupling between these and the econmics of yet-to-be realized fusion power plants is explored. The coupling is two-way: realistic evaluations of the economic (and environmental) requirements for fusion power systems can influence the physics objectives of present-day fusion research programs; physics understanding and innovative ideas can favorably impact the future economics of fusion power systems. Of equal importance is the role that physics/innovation can have on the time scale for the first practical demonstration of fusion power. Given the growing worldwide need for long-term solutions to the problem of energy it is claimed to be crucial that fusion research be carried out on a broad base and in a spirit that both facilitates the growth of physics understanding and fosters innovation. Developing this theme, some examples of mirror-based fusion system concepts are given that illustrate the coupling here described.

  13. Functional relevance of transmembrane domains in membrane fusion.

    PubMed

    Nikolaus, Jörg; Herrmann, Andreas

    2012-11-01

    Membrane fusion is ubiquitous in life. Fusion of biological membranes is mediated by specialized fusion proteins anchored to the bilayers destined to fuse. Here we describe these proteins as being instrumental in viral, intracellular and developmental fusion. Next, we review experimental and theoretical evidence that points to fusion in the different systems as following a common 'fusion through hemifusion' pathway. We also focus on the structure and dynamics of the transmembrane segment that anchors the fusion proteins to the bilayer, and its role in driving fusion. In particular, we highlight the influence of this single segment on the surrounding membrane lipids and on the overall shape of the membrane along the way to fusion.

  14. Expansion of the fusion stalk and its implication for biological membrane fusion.

    PubMed

    Risselada, Herre Jelger; Bubnis, Gregory; Grubmüller, Helmut

    2014-07-29

    Over the past 20 years, it has been widely accepted that membrane fusion proceeds via a hemifusion step before opening of the productive fusion pore. An initial hourglass-shaped lipid structure, the fusion stalk, is formed between the adjacent membrane leaflets (cis leaflets). It remains controversial if and how fusion proteins drive the subsequent transition (expansion) of the stalk into a fusion pore. Here, we propose a comprehensive and consistent thermodynamic understanding in terms of the underlying free-energy landscape of stalk expansion. We illustrate how the underlying free energy landscape of stalk expansion and the concomitant pathway is altered by subtle differences in membrane environment, such as leaflet composition, asymmetry, and flexibility. Nonleaky stalk expansion (stalk widening) requires the formation of a critical trans-leaflet contact. The fusion machinery can mechanically enforce trans-leaflet contact formation either by directly enforcing the trans-leaflets in close proximity, or by (electrostatically) condensing the area of the cis leaflets. The rate of these fast fusion reactions may not be primarily limited by the energetics but by the forces that the fusion proteins are able to exert.

  15. Expansion of the fusion stalk and its implication for biological membrane fusion

    PubMed Central

    Risselada, Herre Jelger; Bubnis, Gregory; Grubmüller, Helmut

    2014-01-01

    Over the past 20 years, it has been widely accepted that membrane fusion proceeds via a hemifusion step before opening of the productive fusion pore. An initial hourglass-shaped lipid structure, the fusion stalk, is formed between the adjacent membrane leaflets (cis leaflets). It remains controversial if and how fusion proteins drive the subsequent transition (expansion) of the stalk into a fusion pore. Here, we propose a comprehensive and consistent thermodynamic understanding in terms of the underlying free-energy landscape of stalk expansion. We illustrate how the underlying free energy landscape of stalk expansion and the concomitant pathway is altered by subtle differences in membrane environment, such as leaflet composition, asymmetry, and flexibility. Nonleaky stalk expansion (stalk widening) requires the formation of a critical trans-leaflet contact. The fusion machinery can mechanically enforce trans-leaflet contact formation either by directly enforcing the trans-leaflets in close proximity, or by (electrostatically) condensing the area of the cis leaflets. The rate of these fast fusion reactions may not be primarily limited by the energetics but by the forces that the fusion proteins are able to exert. PMID:25024174

  16. Use of .sup.3 He.sup.30 + ICRF minority heating to simulate alpha particle heating

    DOEpatents

    Post, Jr., Douglass E.; Hwang, David Q.; Hovey, Jane

    1986-04-22

    Neutron activation due to high levels of neutron production in a first heated deuterium-tritium plasma is substantially reduced by using Ion Cyclotron Resonance Frequency (ICRF) heating of energetic .sup.3 He.sup.++ ions in a second deuterium-.sup.3 He.sup.++ plasma which exhibit an energy distribution and density similar to that of alpha particles in fusion reactor experiments to simulate fusion alpha particle heating in the first plasma. The majority of the fast .sup.3 He.sup.++ ions and their slowing down spectrum can be studied using either a modulated hydrogen beam source for producing excited states of He.sup.+ in combination with spectrometers or double charge exchange with a high energy neutral lithium beam and charged particle detectors at the plasma edge. The maintenance problems thus associated with neutron activation are substantially reduced permitting energetic alpha particle behavior to be studied in near term large fusion experiments.

  17. Linker engineering for fusion protein construction: Improvement and characterization of a GLP-1 fusion protein.

    PubMed

    Kong, Yuelin; Tong, Yue; Gao, Mingming; Chen, Chen; Gao, Xiangdong; Yao, Wenbing

    2016-01-01

    Protein engineering has been successfully applied in protein drug discovery. Using this technology, we previously have constructed a fusion protein by linking the globular domain of adiponectin to the C-terminus of a glucagon-like peptide-1 (GLP-1) analog. Herein, to further improve its bioactivity, we reconstructed this fusion protein by introducing linker peptides of different length and flexibility. The reconstructed fusion proteins were overexpressed in Escherichia coli and purified using nickel affinity chromatography. Their agonist activity towards receptors of GLP-1 and adiponectin were assessed in vitro by using luciferase assay and AMP-activated protein kinase (AMPK) immunoblotting, respectively. The effects of the selected fusion protein on glucose and lipid metabolism were evaluated in mice. The fusion protein reconstructed using a linker peptide of AMGPSSGAPGGGGS showed high potency in activating GLP-1 receptor and triggering AMPK phosphorylation via activating the adiponectin receptor. Remarkably, the optimized fusion protein was highly effective in lowering blood glucose and lipids in mice. Collectively, these findings demonstrate that the bioactivity of this GLP-1 fusion protein can be significantly promoted by linker engineering, and indicate that the optimized GLP-1 fusion protein is a promising lead structure for anti-diabetic drug discovery.

  18. A semi-analytic model of magnetized liner inertial fusion

    SciTech Connect

    McBride, Ryan D.; Slutz, Stephen A.

    2015-05-15

    Presented is a semi-analytic model of magnetized liner inertial fusion (MagLIF). This model accounts for several key aspects of MagLIF, including: (1) preheat of the fuel (optionally via laser absorption); (2) pulsed-power-driven liner implosion; (3) liner compressibility with an analytic equation of state, artificial viscosity, internal magnetic pressure, and ohmic heating; (4) adiabatic compression and heating of the fuel; (5) radiative losses and fuel opacity; (6) magnetic flux compression with Nernst thermoelectric losses; (7) magnetized electron and ion thermal conduction losses; (8) end losses; (9) enhanced losses due to prescribed dopant concentrations and contaminant mix; (10) deuterium-deuterium and deuterium-tritium primary fusion reactions for arbitrary deuterium to tritium fuel ratios; and (11) magnetized α-particle fuel heating. We show that this simplified model, with its transparent and accessible physics, can be used to reproduce the general 1D behavior presented throughout the original MagLIF paper [S. A. Slutz et al., Phys. Plasmas 17, 056303 (2010)]. We also discuss some important physics insights gained as a result of developing this model, such as the dependence of radiative loss rates on the radial fraction of the fuel that is preheated.

  19. Gyrokinetic Simulation of TAE in Fusion plasmas

    NASA Astrophysics Data System (ADS)

    Wang, Zhixuan

    Linear gyrokinetic simulation of fusion plasmas finds a radial localization of the toroidal Alfvén eigenmodes (TAE) due to the non-perturbative energetic particles (EP) contribution. The EP-driven TAE has a radial mode width much smaller than that predicted by the magnetohydrodynamic (MHD) theory. The TAE radial position stays around the strongest EP pressure gradients when the EP profile evolves. The non-perturbative EP contribution is also the main cause for the breaking of the radial symmetry of the ballooning mode structure and for the dependence of the TAE frequency on the toroidal mode number. These phenomena are beyond the picture of the conventional MHD theory. Linear gyrokinetic simulation of the electron cyclotron heating (ECH) experiments on DIII-D successfully recover the TAE and RSAE. The EP profile, rather than the electron temperature, is found to be the key factor determining whether TAE or RSAE is the dominant mode in the system in our simulation. Investigation on the nonlinear gyrokinetic simulation model reveals a missing nonlinear term which has important contributions to the zonal magnetic fields. A new fluid-electron hybrid model is proposed to keep this nonlinear term in the lowest order fluid part. Nonlinear simulation of TAE using DIII-D parameters confirms the importance of this new term for the zonal magnetic fields. It is also found that zonal structures dominated by zonal electric fields are forced driven at about twice the linear growth rate of TAE in the linear phase. The zonal flows then limit the nonlinear saturation level by tearing the eigenmode structures apart. In the nonlinear phase of the simulation, the major frequency in the system chirps down by about 30% and stays there.

  20. Laser Intertial Fusion Energy: Neutronic Design Aspects of a Hybrid Fusion-Fission Nuclear Energy System

    SciTech Connect

    Kramer, Kevin James

    2010-04-08

    This study investigates the neutronics design aspects of a hybrid fusion-fission energy system called the Laser Fusion-Fission Hybrid (LFFH). A LFFH combines current Laser Inertial Confinement fusion technology with that of advanced fission reactor technology to produce a system that eliminates many of the negative aspects of pure fusion or pure fission systems. When examining the LFFH energy mission, a significant portion of the United States and world energy production could be supplied by LFFH plants. The LFFH engine described utilizes a central fusion chamber surrounded by multiple layers of multiplying and moderating media. These layers, or blankets, include coolant plenums, a beryllium (Be) multiplier layer, a fertile fission blanket and a graphite-pebble reflector. Each layer is separated by perforated oxide dispersion strengthened (ODS) ferritic steel walls. The central fusion chamber is surrounded by an ODS ferritic steel first wall. The first wall is coated with 250-500 μm of tungsten to mitigate x-ray damage. The first wall is cooled by Li17Pb83 eutectic, chosen for its neutron multiplication and good heat transfer properties. The Li17Pb83 flows in a jacket around the first wall to an extraction plenum. The main coolant injection plenum is immediately behind the Li17Pb83, separated from the Li17Pb83 by a solid ODS wall. This main system coolant is the molten salt flibe (2LiF-BeF2), chosen for beneficial neutronics and heat transfer properties. The use of flibe enables both fusion fuel production (tritium) and neutron moderation and multiplication for the fission blanket. A Be pebble (1 cm diameter) multiplier layer surrounds the coolant injection plenum and the coolant flows radially through perforated walls across the bed. Outside the Be layer, a fission fuel layer comprised of depleted uranium contained in Tristructural-isotropic (TRISO) fuel particles

  1. Asymptotics of loop quantum gravity fusion coefficients

    NASA Astrophysics Data System (ADS)

    Alesci, Emanuele; Bianchi, Eugenio; Magliaro, Elena; Perini, Claudio

    2010-05-01

    The fusion coefficients from SO(3) to SO(4) play a key role in the definition of spin foam models for the dynamics in loop quantum gravity. In this paper we give a simple analytic formula of the Engle-Pereira-Rovelli-Livine fusion coefficients. We study the large spin asymptotics and show that they map SO(3) semiclassical intertwiners into SU(2)L × SU(2)R semiclassical intertwiners. This non-trivial property opens the possibility for an analysis of the semiclassical behavior of the model.

  2. Fast Radiometry Guided Fusion of Disparity Images

    NASA Astrophysics Data System (ADS)

    Schmid, Stephan; Fritsch, Dieter

    2016-06-01

    Previous work on disparity map fusion has mostly focused on geometric or statistical properties of disparity maps. Since failure of stereo algorithms is often consistent in many frames of a scene, it cannot be detected by such methods. Instead, we propose to use radiometric information from the original camera images together with externally supplied camera pose information to detect mismatches. As radiometric information is local information, the computations in the proposed algorithm for disparity fusion can be decoupled and parallelized to a very large degree, which allows us to easily achieve real-time performance.

  3. Positional effects of fusion partners on the yield and solubility of MBP fusion proteins.

    PubMed

    Raran-Kurussi, Sreejith; Keefe, Karina; Waugh, David S

    2015-06-01

    Escherichia coli maltose-binding protein (MBP) is exceptionally effective at promoting the solubility of its fusion partners. However, there are conflicting reports in the literature claiming that (1) MBP is an effective solubility enhancer only when it is joined to the N-terminus of an aggregation-prone passenger protein, and (2) MBP is equally effective when fused to either end of the passenger. Here, we endeavor to resolve this controversy by comparing the solubility of a diverse set of MBP fusion proteins that, unlike those analyzed in previous studies, are identical in every way except for the order of the two domains. The results indicate that fusion proteins with an N-terminal MBP provide an excellent solubility advantage along with more robust expression when compared to analogous fusions in which MBP is the C-terminal fusion partner. We find that only intrinsically soluble passenger proteins (i.e., those not requiring a solubility enhancer) are produced as soluble fusions when they precede MBP. We also report that even subtle differences in inter-domain linker sequences can influence the solubility of fusion proteins.

  4. The possibilities of cold nuclear fusion of deuterium

    NASA Astrophysics Data System (ADS)

    Jin, Shangxian; Ding, Yibing; Liu, Yongzhen; Wu, Bailu; Yao, Decheng

    1990-01-01

    The possible mechanisms of deuteron-deuteron fusion during electrolytic infusion of deuterons into metallic palladium electrode are studied, and a rough estimations of the fusion rate are made. Our results show that D-D fusion rate in the equilibrium deuteron system at normal temperature and atmospheric pressure can not reach the level which can be measured experimentally.

  5. Functional Analysis of the Putative Fusion Domain of the Baculovirus Envelope Fusion Protein F

    PubMed Central

    Westenberg, Marcel; Veenman, Frank; Roode, Els C.; Goldbach, Rob W.; Vlak, Just M.; Zuidema, Douwe

    2004-01-01

    Group II nucleopolyhedroviruses (NPVs), e.g., Spodoptera exigua MNPV, lack a GP64-like protein that is present in group I NPVs but have an unrelated envelope fusion protein named F. In contrast to GP64, the F protein has to be activated by a posttranslational cleavage mechanism to become fusogenic. In several vertebrate viral fusion proteins, the cleavage activation generates a new N terminus which forms the so-called fusion peptide. This fusion peptide inserts in the cellular membrane, thereby facilitating apposition of the viral and cellular membrane upon sequential conformational changes of the fusion protein. A similar peptide has been identified in NPV F proteins at the N terminus of the large membrane-anchored subunit F1. The role of individual amino acids in this putative fusion peptide on viral infectivity and propagation was studied by mutagenesis. Mutant F proteins with single amino acid changes as well as an F protein with a deleted putative fusion peptide were introduced in gp64-null Autographa californica MNPV budded viruses (BVs). None of the mutations analyzed had an major effect on the processing and incorporation of F proteins in the envelope of BVs. Only two mutants, one with a substitution for a hydrophobic residue (F152R) and one with a deleted putative fusion peptide, were completely unable to rescue the gp64-null mutant. Several nonconservative substitutions for other hydrophobic residues and the conserved lysine residue had only an effect on viral infectivity. In contrast to what was expected from vertebrate virus fusion peptides, alanine substitutions for glycines did not show any effect. PMID:15194771

  6. Fragmentation of suddenly heated liquids

    SciTech Connect

    Blink, J.A.

    1985-03-01

    Fragmentation of free liquids in Inertial Confinement Fusion reactors could determine the upper bound on reactor pulse rate. The x-ray ablated materials must cool and recondense to allow driver beam propagation. The increased surface area caused by fragmentation will enhance the cooling and condensation rates. Relaxation from the suddenly heated state will move a liquid into the negative pressure region under the liquid-vapor P-V dome. The lithium equation of state was used to demonstrate that neutron-induced vaporization uses only a minor fraction of the added heat, much less than would be required to drive the expansion. A 77% expansion of the lithium is required before the rapid vaporization process of spinodal decomposition could begin, and nucleation and growth are too slow to contribute to the expansion.

  7. Overview of the Lockheed Martin Compact Fusion Reactor (CFR) T4B Experiment

    NASA Astrophysics Data System (ADS)

    McGuire, Thomas

    2016-10-01

    The Lockheed Martin Compact Fusion Reactor (CFR) Program endeavors to quickly develop a compact fusion power plant with favorable commercial economics and military utility. The CFR uses a diamagnetic, high beta, magnetically encapsulated, linear ring cusp plasma confinement scheme. The goal of the T4B experiment is to demonstrate a suitable plasma target for heating experiments and to characterize the behavior of plasma sources in the CFR configuration. The design of the T4B experiment will be presented, including discussion of predicted behavior, plasma sources, heating mechanisms, diagnostics suite and relevant numerical modeling. ©2016 Lockheed Martin Corporation. All Rights Reserved.

  8. The rhetoric of science: A case study of the cold fusion controversy

    SciTech Connect

    Hatfield, D.L.

    1992-01-01

    This dissertation examines the circumstances surrounding and the rhetoric involved in the cold fusion controversy begun on March 23, 1989, when two University of Utah electrochemists, Martin Fleischmann and Stanley Pons, announced by press conference the discovery of room-temperature nuclear fusion. The dissertation seeks to determine to what extent a rhetorical analysis of cold fusion discourse may increase understanding of the controversy; the success of Fleischmann and Pons as scientific rhetors; the ways in which scientists' attitudes, values, and assumptions manifest themselves in the discourse; and finally, what may be learned about scientific discourse by examining the cold fusion controversy in particular. Examined were Fleischmann and Pon's initial publication announcing the cold fusion discovery in the Journal of Electroanalytical Chemistry; Steven E. Jones's initial publication of his cold fusion discovery and several representative discourse samples from the journal Nature; and Fleischmann and Pons's latest article in the Journal of Fusion Technology. Cold fusion discourse addressed evidential issues, questioning the existence of the cold fusion phenomenon. Several lines of argument were evoked to address this issue, including experimental competence, experimental replication, external consistency, communality, and disinterestedness. Also discovered is division between electrochemists and physicists over what constitutes valid evidence: electrochemists looked to excess heat production as proof of fusion; physicists looked to neutron production. The study concludes that Fleischmann and Pons followed an unsuccessful rhetorical strategy in their initial published paper. An alternative rhetorical strategy was available to Fleischmann and Pons, one in which they could have interpreted their evidence, thereby evoking a less confrontational response from the scientific community.

  9. Analysis of Fusion Burn Control Approaches Using METIS

    NASA Astrophysics Data System (ADS)

    Boyer, Mark; Schuster, Eugenio; Bremond, Sylvain; Nouailletas, Remy; Artaud, Jean-Francois

    2012-10-01

    Controlling the fusion power through regulation of the plasma density and temperature is one of the most fundamental problems in fusion reactors and will be critical to the success of burning plasma experiments like ITER. In this work, a volume averaged model for the evolution of the density of energy, deuterium and tritium fuel ions, alpha-particles, and impurity ions is used to synthesize nonlinear feedback controllers for stabilizing and modulating the burn condition. Adaptive control techniques are used to account for modeling uncertainty. The control approaches make use of the different possible methods for altering the fusion power, including adjusting the temperature through auxiliary heating, modulating the density or isotopic mix through fueling, and altering the impurity density through impurity injection. The different methods are simulated and compared using a simulation framework based around METIS, a module of the CRONOS code. The simulations include the effects of 1D plasma profiles and particle recycling, and the framework allows for testing the robustness and performance of the controllers in various scenarios, including confinement changes, impurity content changes, and actuators faults.

  10. On some properties of SU(3) fusion coefficients

    NASA Astrophysics Data System (ADS)

    Coquereaux, Robert; Zuber, Jean-Bernard

    2016-11-01

    Three aspects of the SU(3) fusion coefficients are revisited: the generating polynomials of fusion coefficients are written explicitly; some curious identities generalizing the classical Freudenthal-de Vries formula are derived; and the properties of the fusion coefficients under conjugation of one of the factors, previously analyzed in the classical case, are extended to the affine algebra su ˆ (3) at finite level.

  11. Estimating the melting point, entropy of fusion, and enthalpy of ...

    EPA Pesticide Factsheets

    The entropies of fusion, enthalies of fusion, and melting points of organic compounds can be estimated through three models developed using the SPARC (SPARC Performs Automated Reasoning in Chemistry) platform. The entropy of fusion is modeled through a combination of interaction terms and physical descriptors. The enthalpy of fusion is modeled as a function of the entropy of fusion, boiling point, and fexibility of the molecule. The melting point model is the enthlapy of fusion divided by the entropy of fusion. These models were developed in part to improve SPARC's vapor pressure and solubility models. These models have been tested on 904 unique compounds. The entropy model has a RMS of 12.5 J mol-1K-1. The enthalpy model has a RMS of 4.87 kJ mol-1. The melting point model has a RMS of 54.4°C. Published in the journal, SAR and QSAR in Environmental Research

  12. Inertial Confinement Fusion alpha-heating signatures in prompt gamma-ray measurements at the National Ignition Facility

    NASA Astrophysics Data System (ADS)

    Church, Jennifer; Herrmann, Hans; Cerjan, Charlie; Sayre, Daniel; Carpenter, Arthur; Liebman, Judy; Stoeffl, Wolfgang; Kim, Yongho

    2015-11-01

    Prompt gamma-rays measured at the National Ignition Facility (NIF) with the Gamma-ray Reaction History detector (GRH) supply vital diagnostic information, such as the peak burn time, burn width, and total neutron yield, from prompt DT-fusion gamma-ray emission during high convergence implosion experiments. Additionally, the stagnated cold shell density distribution may be inferred from the time-integrated, calibrated 12C (n,n' γ) signal, thus providing estimates of remaining ablator carbon areal density. Furthermore, simulations suggest that alpha heating signatures might be accessible using more highly resolved temporal gamma-ray emission. Correlation of these signatures with time-dependent neutron emission will constrain the implosion dynamics immediately prior to thermonuclear burn. Measurement of these gamma-ray signatures will be discussed along with updates on our work toward inferred total DT yield and 12C areal density. This work performed under the auspices of the U.S. Dept. of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07-NA27344, LLNL-ABS-670282.

  13. Fusion Techniques for the Oxidation of Refractory Actinide Oxides

    SciTech Connect

    Rudisill, T.S.

    1999-04-15

    Small-scale experiments were performed to demonstrate the feasibility of fusing refractory actinide oxides with a series of materials commonly used to decompose minerals, glasses, and other refractories as a pretreatment to dissolution and subsequent recovery operations. In these experiments, 1-2 g of plutonium or neptunium oxide (PuO2 or NpO2) were calcined at 900 degrees Celsius, mixed and heated with the fusing reagent(s), and dissolved. For refractory PuO2, the most effective material tested was a lithium carbonate (Li2CO3)/sodium tetraborate (Na2B4O7) mixture which aided in the recovery of 90 percent of the plutonium. The fused product was identified as a lithium plutonate (Li3PuO4) by x-ray diffraction. The use of a Li2CO3/Na2B4O7 mixture to solubilize high-fired NpO2 was not as effective as demonstrated for refractory PuO2. In a small-scale experiment, 25 percent of the NpO2 was oxidized to a neptunium (VI) species that dissolved in nitric acid. The remaining neptunium was then easily recovered from the residue by fusing with sodium peroxide (Na2O2). Approximately 70 percent of the neptunium dissolved in water to yield a basic solution of neptunium (VII). The remainder was recovered as a neptunium (VI) solution by dissolving the residue in 8M nitric acid. In subsequent experiments with Na2O2, the ratio of neptunium (VII) to (VI) was shown to be a function of the fusion temperature, with higher temperatures (greater than approximately 400 degrees C) favoring the formation of neptunium (VII). The fusion of an actual plutonium-containing residue with Na2O2 and subsequent dissolution was performed to demonstrate the feasibility of a pretreatment process on a larger scale. Sodium peroxide was chosen due

  14. Application of Kalman Filter on Multisensor Fusion Tracking

    DTIC Science & Technology

    1992-12-01

    AD-A257 335 NAVAL POSTGRADUATE SCHOOL Monterey, California DTIC ELCT THESIS APPLICATION OF KALMAN FILTER ON MULTISENSOR FUSION TRACKING by Brian...WORK UNIT ELEMENT NO NO NO ACCESSION NO 11 TITLE (Include Security Classification) PPLICATION OF KALMAN FILTER ON MULTISENSOR FUSION TRACKING 12...FIELD GROUP SUB-GROUP fusion, Kalman Filter Multisensor Fusion Tracking 19 ABSTRACT (Continue on reverse if necessary and identify by block number)he

  15. Massachusetts Institute of Technology, Plasma Fusion Center, Technical Research Programs

    SciTech Connect

    Davidson, Ronald C.

    1980-08-01

    A review is given of the technical programs carried out by the Plasma Fusion Center. The major divisions of work areas are applied plasma research, confinement experiments, fusion technology and engineering, and fusion systems. Some objectives and results of each program are described. (MOW)

  16. Application of Fusion Gyrotrons to Enhanced Geothermal Systems (EGS)

    NASA Astrophysics Data System (ADS)

    Woskov, P.; Einstein, H.; Oglesby, K.

    2013-10-01

    The potential size of geothermal energy resources is second only to fusion energy. Advances are needed in drilling technology and heat reservoir formation to realize this potential. Millimeter-wave (MMW) gyrotrons and related technologies developed for fusion energy research could contribute to enabling EGS. Directed MMW energy can be used to advance rock penetration capabilities, borehole casing, and fracking. MMWs are ideally suited because they can penetrate through small particulate extraction plumes, can be efficiently guided long distances in borehole dimensions, and continuous megawatt sources are commercially available. Laboratory experiments with a 10 kW, 28 GHz CPI gyrotron have shown that granite rock can be fractured and melted with power intensities of about 1 kW/cm2 and minute exposure times. Observed melted rock MMW emissivity and estimated thermodynamics suggest that penetrating hot, hard crystalline rock formations may be economic with fusion research developed MMW sources. Supported by USDOE, Office of Energy Efficiency and Renewable Energy and Impact Technologies, LLC.

  17. Fusion welding of a modern borated stainless steel

    SciTech Connect

    Robino, C.V.; Cieslak, M.J.

    1997-01-01

    Experiments designed to assess the fabrication and service weldability of 304B4A borated stainless steel were conducted. Welding procedures and parameters for manual gas tungsten arc (GTA) welding, autogenous electron beam (EB) welding and filler-added EB welding were developed and found to be similar to those for austenitic stainless steels. Following the procedure development, four test welds were produced and evaluated by microstructural analysis and Charpy impact testing. Further samples were used for determination of the postweld heat treatment (PWHT) response of the welds. The fusion zone structure of welds in this alloy consists of primary austenite dendrites with an interdendritic eutectic-like austenite/boride constituent. Welds also show an appreciable partially molten zone that consists of the austenite/boride eutectic surrounding unmelted austenite islands. The microstructure of the EB welds was substantially finer than that of the GTA welds, and boride coarsening was not observed in the solid state heat-affected zone (HAZ) of either weld type. The impact toughness of as-welded samples was found to be relatively poor, averaging less than 10 J for both GTA and EB welds. For fusion zone notched GTA and EB samples and centerline notched EB samples, fracture generally occurred along the boundary between the partially molten and solid-state regions of the HAZ. The results of the PWHT study were very encouraging, with typical values of the impact energy for HAZ notched samples approaching 40 J, or twice the minimum code-acceptable value.

  18. Thrust enhancement of the gasdynamic mirror (GDM) fusion propulsion system

    NASA Astrophysics Data System (ADS)

    Kammash, Terry; Lee, Myoung-Jae; Poston, David I.

    1997-01-01

    The gasdynamic mirror propulsion system is a device that utilizes a magnetic mirror configuration to confine a hot plasma to allow fusion reactions to take place while ejecting a fraction of the energetic charged particles through one end to generate thrust. Because the fusion fuel is generally an isotope of hydrogen, e.g., deuterium or tritium, this propulsion device is capable of producing very large specific impulses (e.g., 200,000 seconds) but at modest thrusts. Since large thrusts are desirable, not only for reducing travel time but also for lifting sizable payloads, we have examined methods by which GDM's thrust could be enhanced. The first consists of utilizing the radiation generated by the plasma, namely bremsstrahlung and synchrotron radiation, to heat a hydrogen propellant which upon exhausting through a nozzle produces the additional thrust. We asses the performance in this case by using an ideal model that ignores heat transfer considerations of the chamber wall, and one that takes into account heat flow and wall temperature limitations. We find in the case of a DT burning plasma that although thrust enhancement is significant, it was more than offset by the large drop in the specific impulse and a concomitant increase in travel time. The second method consisted of not altering the original GDM operation, but simply increasing the density of the injected plasma to achieve higher thrust. It is shown that the latter approach is more effective since it is compatible with improved performance in that it reduces trip time but at the expense of larger vehicle mass. For a D-He3 burning device the use of hydrogen to enhance thrust appears to be more desirable since the radiated power that goes into heating the hydrogen propellant is quite large.

  19. Gene fusion analysis of membrane protein topology: a direct comparison of alkaline phosphatase and beta-lactamase fusions.

    PubMed Central

    Prinz, W A; Beckwith, J

    1994-01-01

    To compare two approaches to analyzing membrane protein topology, a number of alkaline phosphatase fusions to membrane proteins were converted to beta-lactamase fusions. While some alkaline phosphatase fusions near the N terminus of cytoplasmic loops of membrane proteins have anomalously high levels of activity, the equivalent beta-lactamase fusions do not. This disparity may reflect differences in the folding of beta-lactamase and alkaline phosphatase in the cytoplasm. PMID:7929016

  20. Fundamentals of heat measurement. [heat flux transducers

    NASA Technical Reports Server (NTRS)

    Gerashchenko, O. A.

    1979-01-01

    Various methods and devices for obtaining experimental data on heat flux density over wide ranges of temperature and pressure are examined. Laboratory tests and device fabrication details are supplemented by theoretical analyses of heat-conduction and thermoelectric effects, providing design guidelines and information relevant to further research and development. A theory defining the measure of correspondence between transducer signal and the measured heat flux is established for individual (isolated) heat flux transducers subject to space and time-dependent loading. An analysis of the properties of stacked (series-connected) transducers of various types (sandwich-type, plane, and spiral) is used to derive a similarity theory providing general governing relationships. The transducers examined are used in 36 types of derivative devices involving direct heat loss measurements, heat conduction studies, radiation pyrometry, calorimetry in medicine and industry and nuclear reactor dosimetry.

  1. Measurement of membrane fusion activity from viral membrane fusion proteins based on a fusion-dependent promoter induction system in insect cells

    PubMed Central

    Slack, J. M.; Blissard, G. W.

    2013-01-01

    Summary A number of viral membrane fusion proteins can be expressed alone on the surface of host cells, then triggered to induce cell-to-cell fusion or syncytium formation. Although rapid and easily observed, syncytium formation is not easily quantified and differences in fusion activity are not easily distinguished or measured. To address this problem, we developed a rapid and quantitative cell-to-cell fusion system that is useful for comparative analysis and may be suitable for high throughput screening. In this system, expression of a reporter protein, the enhanced green fluorescent protein (EGFP), is dependent on cell-to-cell fusion. Spodoptera frugiperda (Sf9) insect cells expressing a chimeric Lac Repressor-IE1 protein were fused to Sf9 cells containing an EGFP reporter construct under the control of a responsive lac operator containing promoter. Membrane fusion efficiency was measured from the resulting EGFP fluorescence activity. Sf9 cells expressing the Orgyia pseudotsugata Multicapsid Nucleopolyhedrovirus (OpMNPV) GP64 envelope fusion protein were used as a model to test this fusion assay. Subtle changes in fusion activities of GP64 proteins containing single amino acid substitutions in a putative membrane fusion domain were distinguished, and decreases in EGFP fluorescence corresponded to decreases in the hydrophobicity in the small putative membrane fusion domain. PMID:11562545

  2. The VISTA spacecraft: Advantages of ICF (Inertial Confinement Fusion) for interplanetary fusion propulsion applications

    SciTech Connect

    Orth, C.D.; Klein, G.; Sercel, J.; Hoffman, N.; Murray, K.; Chang-Diaz, F.

    1987-10-02

    Inertial Confinement Fusion (ICF) is an attractive engine power source for interplanetary manned spacecraft, especially for near-term missions requiring minimum flight duration, because ICF has inherent high power-to-mass ratios and high specific impulses. We have developed a new vehicle concept called VISTA that uses ICF and is capable of round-trip manned missions to Mars in 100 days using A.D. 2020 technology. We describe VISTA's engine operation, discuss associated plasma issues, and describe the advantages of DT fuel for near-term applications. Although ICF is potentially superior to non-fusion technologies for near-term interplanetary transport, the performance capabilities of VISTA cannot be meaningfully compared with those of magnetic-fusion systems because of the lack of a comparable study of the magnetic-fusion systems. We urge that such a study be conducted.

  3. The VISTA spacecraft: Advantages of ICF (Inertial Confinement Fusion) for interplanetary fusions propulsion applications

    NASA Technical Reports Server (NTRS)

    Orth, Charles D.; Klein, Gail; Sercel, Joel; Hoffman, Nate; Murray, Kathy; Chang-Diaz, Franklin

    1987-01-01

    Inertial Confinement Fusion (ICF) is an attractive engine power source for interplanetary manned spacecraft, especially for near-term missions requiring minimum flight duration, because ICF has inherent high power-to-mass ratios and high specific impulses. We have developed a new vehicle concept called VISTA that uses ICF and is capable of round-trip manned missions to Mars in 100 days using A.D. 2020 technology. We describe VISTA's engine operation, discuss associated plasma issues, and describe the advantages of DT fuel for near-term applications. Although ICF is potentially superior to non-fusion technologies for near-term interplanetary transport, the performance capabilities of VISTA cannot be meaningfully compared with those of magnetic-fusion systems because of the lack of a comparable study of the magnetic-fusion systems. We urge that such a study be conducted.

  4. Effect of particle pinch on the fusion performance and profile features of an international thermonuclear experimental reactor-like fusion reactor

    SciTech Connect

    Wang, Shijia Wang, Shaojie

    2015-04-15

    The evolution of the plasma temperature and density in an international thermonuclear experimental reactor (ITER)-like fusion device has been studied by numerically solving the energy transport equation coupled with the particle transport equation. The effect of particle pinch, which depends on the magnetic curvature and the safety factor, has been taken into account. The plasma is primarily heated by the alpha particles which are produced by the deuterium-tritium fusion reactions. A semi-empirical method, which adopts the ITERH-98P(y,2) scaling law, has been used to evaluate the transport coefficients. The fusion performances (the fusion energy gain factor, Q) similar to the ITER inductive scenario and non-inductive scenario (with reversed magnetic shear) are obtained. It is shown that the particle pinch has significant effects on the fusion performance and profiles of a fusion reactor. When the volume-averaged density is fixed, particle pinch can lower the pedestal density by ∼30%, with the Q value and the central pressure almost unchanged. When the particle source or the pedestal density is fixed, the particle pinch can significantly enhance the Q value by  60%, with the central pressure also significantly raised.

  5. Assessment of NDE Methods to Detect Lack of Fusion in HDPE Butt Fusion Joints

    SciTech Connect

    Crawford, Susan L.; Doctor, Steven R.; Cinson, Anthony D.; Watts, Michael W.; Moran, Traci L.; Anderson, Michael T.

    2011-07-31

    Studies at the Pacific Northwest National Laboratory (PNNL) in Richland, Washington, were conducted to evaluate nondestructive examinations (NDE) coupled with mechanical testing of butt fusion joints in high-density polyethylene (HDPE) pipe for assessing lack of fusion. The work provided information to the United States Nuclear Regulatory Commission (NRC) on the effectiveness of volumetric inspection techniques of HDPE butt fusion joints in Section III, Division 1, Class 3, buried piping systems in nuclear power plants. This paper describes results from assessments using ultrasonic and microwave nondestructive techniques and mechanical testing with the high-speed tensile impact test and the side-bend test for determining joint integrity. A series of butt joints were fabricated in 3408, 12-inch (30.5-cm) IPS DR-11 HDPE material by varying the fusion parameters to create good joints and joints containing a range of lack-of-fusion conditions. Six of these butt joints were volumetrically examined with time-of-flight diffraction (TOFD), phased-array (PA) ultrasound, and the Evisive microwave system. The outer diameter (OD) weld beads were removed for microwave evaluation and the pipes ultrasonically re-evaluated. In two of the six pipes, both the outer and inner diameter (ID) weld beads were removed and the pipe joints re-evaluated. Some of the pipes were sectioned and the joints destructively evaluated with the high-speed tensile test and the side-bend test. The fusion parameters, nondestructive and destructive evaluation results have been correlated to validate the effectiveness of what each NDE technology detects and what each does not detect. There was no single NDE method that detected all of the lack-of-fusion flaws but a combination of NDE methods did detect most of the flaws.

  6. Evaluation of taste solutions by sensor fusion

    SciTech Connect

    Kojima, Yohichiro; Sato, Eriko; Atobe, Masahiko; Nakashima, Miki; Kato, Yukihisa; Nonoue, Koichi; Yamano, Yoshimasa

    2009-05-23

    In our previous studies, properties of taste solutions were discriminated based on sound velocity and amplitude of ultrasonic waves propagating through the solutions. However, to make this method applicable to beverages which contain many taste substances, further studies are required. In this study, the waveform of an ultrasonic wave with frequency of approximately 5 MHz propagating through a solution was measured and subjected to frequency analysis. Further, taste sensors require various techniques of sensor fusion to effectively obtain chemical and physical parameter of taste solutions. A sensor fusion method of ultrasonic wave sensor and various sensors, such as the surface plasmon resonance (SPR) sensor, to estimate tastes were proposed and examined in this report. As a result, differences among pure water and two basic taste solutions were clearly observed as differences in their properties. Furthermore, a self-organizing neural network was applied to obtained data which were used to clarify the differences among solutions.

  7. Identification of targetable FGFR gene fusions in diverse cancers.

    PubMed

    Wu, Yi-Mi; Su, Fengyun; Kalyana-Sundaram, Shanker; Khazanov, Nickolay; Ateeq, Bushra; Cao, Xuhong; Lonigro, Robert J; Vats, Pankaj; Wang, Rui; Lin, Su-Fang; Cheng, Ann-Joy; Kunju, Lakshmi P; Siddiqui, Javed; Tomlins, Scott A; Wyngaard, Peter; Sadis, Seth; Roychowdhury, Sameek; Hussain, Maha H; Feng, Felix Y; Zalupski, Mark M; Talpaz, Moshe; Pienta, Kenneth J; Rhodes, Daniel R; Robinson, Dan R; Chinnaiyan, Arul M

    2013-06-01

    Through a prospective clinical sequencing program for advanced cancers, four index cases were identified which harbor gene rearrangements of FGFR2, including patients with cholangiocarcinoma, breast cancer, and prostate cancer. After extending our assessment of FGFR rearrangements across multiple tumor cohorts, we identified additional FGFR fusions with intact kinase domains in lung squamous cell cancer, bladder cancer, thyroid cancer, oral cancer, glioblastoma, and head and neck squamous cell cancer. All FGFR fusion partners tested exhibit oligomerization capability, suggesting a shared mode of kinase activation. Overexpression of FGFR fusion proteins induced cell proliferation. Two bladder cancer cell lines that harbor FGFR3 fusion proteins exhibited enhanced susceptibility to pharmacologic inhibition in vitro and in vivo. Because of the combinatorial possibilities of FGFR family fusion to a variety of oligomerization partners, clinical sequencing efforts, which incorporate transcriptome analysis for gene fusions, are poised to identify rare, targetable FGFR fusions across diverse cancer types.

  8. Exocytotic fusion pores are composed of both lipids and proteins

    PubMed Central

    Bao, Huan; Goldschen-Ohm, Marcel; Jeggle, Pia; Chanda, Baron; Edwardson, J Michael; Chapman, Edwin R

    2016-01-01

    During exocytosis, fusion pores form the first aqueous connection that allows escape of neurotransmitters and hormones from secretory vesicles. Although it is well established that SNARE proteins catalyze fusion, the structure and composition of fusion pores remain unknown. Here, we exploited the rigid framework and defined size of nanodiscs to interrogate the properties of reconstituted fusion pores, using the neurotransmitter glutamate as a content-mixing marker. Efficient Ca2+-stimulated bilayer fusion, and glutamate release, occurred with approximately two molecules of mouse synaptobrevin 2 reconstituted into ~6-nm nanodiscs. The transmembrane domains of SNARE proteins assumed distinct roles in lipid mixing versus content release and were exposed to polar solvent during fusion. Additionally, tryptophan substitutions at specific positions in these transmembrane domains decreased glutamate flux. Together, these findings indicate that the fusion pore is a hybrid structure composed of both lipids and proteins. PMID:26656855

  9. Experimental demonstration of fusion-relevant conditions in magnetized liner inertial fusion

    DOE PAGES

    Gomez, Matthew R.; Slutz, Stephen A..; Sefkow, Adam B.; ...

    2014-10-06

    This Letter presents results from the first fully integrated experiments testing the magnetized liner inertial fusion concept [S.A. Slutz et al., Phys. Plasmas 17, 056303 (2010)], in which a cylinder of deuterium gas with a preimposed axial magnetic field of 10 T is heated by Z beamlet, a 2.5 kJ, 1 TW laser, and magnetically imploded by a 19 MA current with 100 ns rise time on the Z facility. Despite a predicted peak implosion velocity of only 70 km/s, the fuel reaches a stagnation temperature of approximately 3 keV, with Te ≈ Ti, and produces up to 2e12 thermonuclearmore » DD neutrons. In this study, X-ray emission indicates a hot fuel region with full width at half maximum ranging from 60 to 120 μm over a 6 mm height and lasting approximately 2 ns. The number of secondary deuterium-tritium neutrons observed was greater than 1010, indicating significant fuel magnetization given that the estimated radial areal density of the plasma is only 2 mg/cm2.« less

  10. Experimental demonstration of fusion-relevant conditions in magnetized liner inertial fusion

    SciTech Connect

    Gomez, Matthew R.; Slutz, Stephen A..; Sefkow, Adam B.; Sinars, Daniel B.; Hahn, Kelly D.; Hansen, Stephanie B.; Harding, Eric C.; Knapp, Patrick F.; Schmit, Paul F.; Jennings, Christopher A.; Awe, Thomas James; Geissel, Matthias; Rovang, Dean C.; Chandler, Gordon A.; Cooper, Gary Wayne; Cuneo, Michael Edward; Harvey-Thompson, Adam James; Herrmann, Mark; Hess, M. H.; Johns, Owen; Lamppa, Derek C.; Martin, Matthew R.; McBride, Ryan D.; Peterson, Kyle J.; Porter, John L.; Robertson, Grafton Kincannon; Rochau, Gregory A.; Ruiz, Carlos L.; Savage, Mark E.; Smith, Ian C.; Stygar, William A.; Vesey, Roger A.

    2014-10-06

    This Letter presents results from the first fully integrated experiments testing the magnetized liner inertial fusion concept [S.A. Slutz et al., Phys. Plasmas 17, 056303 (2010)], in which a cylinder of deuterium gas with a preimposed axial magnetic field of 10 T is heated by Z beamlet, a 2.5 kJ, 1 TW laser, and magnetically imploded by a 19 MA current with 100 ns rise time on the Z facility. Despite a predicted peak implosion velocity of only 70 km/s, the fuel reaches a stagnation temperature of approximately 3 keV, with Te ≈ Ti, and produces up to 2e12 thermonuclear DD neutrons. In this study, X-ray emission indicates a hot fuel region with full width at half maximum ranging from 60 to 120 μm over a 6 mm height and lasting approximately 2 ns. The number of secondary deuterium-tritium neutrons observed was greater than 1010, indicating significant fuel magnetization given that the estimated radial areal density of the plasma is only 2 mg/cm2.

  11. Regulation of cell-cell fusion by nanotopography

    NASA Astrophysics Data System (ADS)

    Padmanabhan, Jagannath; Augelli, Michael J.; Cheung, Bettina; Kinser, Emily R.; Cleary, Barnett; Kumar, Priyanka; Wang, Renhao; Sawyer, Andrew J.; Li, Rui; Schwarz, Udo D.; Schroers, Jan; Kyriakides, Themis R.

    2016-09-01

    Cell-cell fusion is fundamental to a multitude of biological processes ranging from cell differentiation and embryogenesis to cancer metastasis and biomaterial-tissue interactions. Fusogenic cells are exposed to biochemical and biophysical factors, which could potentially alter cell behavior. While biochemical inducers of fusion such as cytokines and kinases have been identified, little is known about the biophysical regulation of cell-cell fusion. Here, we designed experiments to examine cell-cell fusion using bulk metallic glass (BMG) nanorod arrays with varying biophysical cues, i.e. nanotopography and stiffness. Through independent variation of stiffness and topography, we found that nanotopography constitutes the primary biophysical cue that can override biochemical signals to attenuate fusion. Specifically, nanotopography restricts cytoskeletal remodeling-associated signaling, which leads to reduced fusion. This finding expands our fundamental understanding of the nanoscale biophysical regulation of cell fusion and can be exploited in biomaterials design to induce desirable biomaterial-tissue interactions.

  12. Identification of Targetable FGFR Gene Fusions in Diverse Cancers

    PubMed Central

    Wu, Yi-Mi; Su, Fengyun; Kalyana-Sundaram, Shanker; Khazanov, Nick; Ateeq, Bushra; Cao, Xuhong; Lonigro, Robert J.; Vats, Pankaj; Wang, Rui; Lin, Su-Fang; Cheng, Ann-Joy; Kunju, Lakshmi P.; Siddiqui, Javed; Tomlins, Scott A.; Wyngaard, Peter; Sadis, Seth; Roychowdhury, Sameek; Hussain, Maha H.; Feng, Felix Y.; Zalupski, Mark M.; Talpaz, Moshe; Pienta, Kenneth J.; Rhodes, Daniel R.; Robinson, Dan R.; Chinnaiyan, Arul M.

    2013-01-01

    Through a prospective clinical sequencing program for advanced cancers, four index cases were identified which harbor gene rearrangements of FGFR2 including patients with cholangiocarcinoma, breast cancer, and prostate cancer. After extending our assessment of FGFR rearrangements across multiple tumor cohorts, we identified additional FGFR gene fusions with intact kinase domains in lung squamous cell cancer, bladder cancer, thyroid cancer, oral cancer, glioblastoma, and head and neck squamous cell cancer. All FGFR fusion partners tested exhibit oligomerization capability, suggesting a shared mode of kinase activation. Overexpression of FGFR fusion proteins induced cell proliferation. Two bladder cancer cell lines that harbor FGFR3 fusion proteins exhibited enhanced susceptibility to pharmacologic inhibition in vitro and in vivo. Due to the combinatorial possibilities of FGFR family fusion to a variety of oligomerization partners, clinical sequencing efforts which incorporate transcriptome analysis for gene fusions are poised to identify rare, targetable FGFR fusions across diverse cancer types. PMID:23558953

  13. Regulation of cell-cell fusion by nanotopography

    PubMed Central

    Padmanabhan, Jagannath; Augelli, Michael J.; Cheung, Bettina; Kinser, Emily R.; Cleary, Barnett; Kumar, Priyanka; Wang, Renhao; Sawyer, Andrew J.; Li, Rui; Schwarz, Udo D.; Schroers, Jan; Kyriakides, Themis R.

    2016-01-01

    Cell-cell fusion is fundamental to a multitude of biological processes ranging from cell differentiation and embryogenesis to cancer metastasis and biomaterial-tissue interactions. Fusogenic cells are exposed to biochemical and biophysical factors, which could potentially alter cell behavior. While biochemical inducers of fusion such as cytokines and kinases have been identified, little is known about the biophysical regulation of cell-cell fusion. Here, we designed experiments to examine cell-cell fusion using bulk metallic glass (BMG) nanorod arrays with varying biophysical cues, i.e. nanotopography and stiffness. Through independent variation of stiffness and topography, we found that nanotopography constitutes the primary biophysical cue that can override biochemical signals to attenuate fusion. Specifically, nanotopography restricts cytoskeletal remodeling-associated signaling, which leads to reduced fusion. This finding expands our fundamental understanding of the nanoscale biophysical regulation of cell fusion and can be exploited in biomaterials design to induce desirable biomaterial-tissue interactions. PMID:27615159

  14. Modelling third harmonic ion cyclotron acceleration of deuterium beams for JET fusion product studies experiments

    NASA Astrophysics Data System (ADS)

    Schneider, M.; Johnson, T.; Dumont, R.; Eriksson, J.; Eriksson, L.-G.; Giacomelli, L.; Girardo, J.-B.; Hellsten, T.; Khilkevitch, E.; Kiptily, V. G.; Koskela, T.; Mantsinen, M.; Nocente, M.; Salewski, M.; Sharapov, S. E.; Shevelev, A. E.; Contributors, JET

    2016-11-01

    Recent JET experiments have been dedicated to the studies of fusion reactions between deuterium (D) and Helium-3 (3He) ions using neutral beam injection (NBI) in synergy with third harmonic ion cyclotron radio-frequency heating (ICRH) of the beam. This scenario generates a fast ion deuterium tail enhancing DD and D3He fusion reactions. Modelling and measuring the fast deuterium tail accurately is essential for quantifying the fusion products. This paper presents the modelling of the D distribution function resulting from the NBI+ICRF heating scheme, reinforced by a comparison with dedicated JET fast ion diagnostics, showing an overall good agreement. Finally, a sawtooth activity for these experiments has been observed and interpreted using SPOT/RFOF simulations in the framework of Porcelli’s theoretical model, where NBI+ICRH accelerated ions are found to have a strong stabilizing effect, leading to monster sawteeth.

  15. Effects of magnetization on fusion product trapping and secondary neutron spectra

    SciTech Connect

    Knapp, Patrick F.; Schmit, Paul F.; Hansen, Stephanie B.; Gomez, Matthew R.; Hahn, Kelly D.; Sinars, Daniel Brian; Peterson, Kyle J.; Slutz, Stephen A.; Sefkow, Adam B.; Awe, Thomas James; Harding, Eric; Jennings, Christopher A.; Desjarlais, M. P.; Chandler, Gordon A.; Cooper, Gary Wayne; Cuneo, Michael Edward; Geissel, Matthias; Harvey-Thompson, Adam James; Porter, John L.; Rochau, Gregory A.; Rovang, Dean C.; Ruiz, Carlos L.; Savage, Mark E.; Smith, Ian C.; Stygar, William A.; Herrmann, Mark

    2015-05-14

    In magnetizing the fusion fuel in inertial confinement fusion (ICF) systems, we found that the required stagnation pressure and density can be relaxed dramatically. This happens because the magnetic field insulates the hot fuel from the cold pusher and traps the charged fusion burn products. This trapping allows the burn products to deposit their energy in the fuel, facilitating plasma self-heating. Here, we report on a comprehensive theory of this trapping in a cylindrical DD plasma magnetized with a purely axial magnetic field. Using this theory, we are able to show that the secondary fusion reactions can be used to infer the magnetic field-radius product, BR, during fusion burn. This parameter, not ρR, is the primary confinement parameter in magnetized ICF. Using this method, we analyze data from recent Magnetized Liner InertialFusion experiments conducted on the Z machine at Sandia National Laboratories. Furthermore, we show that in these experiments BR ≈ 0.34(+0.14/-0.06) MG · cm, a ~ 14× increase in BR from the initial value, and confirming that the DD-fusion tritons are magnetized at stagnation. Lastly, this is the first experimental verification of charged burn product magnetization facilitated by compression of an initial seed magnetic flux.

  16. Effects of magnetization on fusion product trapping and secondary neutron spectra

    SciTech Connect

    Knapp, P. F.; Schmit, P. F.; Hansen, S. B.; Gomez, M. R.; Hahn, K. D.; Sinars, D. B.; Peterson, K. J.; Slutz, S. A.; Sefkow, A. B.; Awe, T. J.; Harding, E.; Jennings, C. A.; Desjarlais, M. P.; Chandler, G. A.; Cooper, G. W.; Cuneo, M. E.; Geissel, M.; Harvey-Thompson, A. J.; Porter, J. L.; Rochau, G. A.; and others

    2015-05-15

    By magnetizing the fusion fuel in inertial confinement fusion (ICF) systems, the required stagnation pressure and density can be relaxed dramatically. This happens because the magnetic field insulates the hot fuel from the cold pusher and traps the charged fusion burn products. This trapping allows the burn products to deposit their energy in the fuel, facilitating plasma self-heating. Here, we report on a comprehensive theory of this trapping in a cylindrical DD plasma magnetized with a purely axial magnetic field. Using this theory, we are able to show that the secondary fusion reactions can be used to infer the magnetic field-radius product, BR, during fusion burn. This parameter, not ρR, is the primary confinement parameter in magnetized ICF. Using this method, we analyze data from recent Magnetized Liner Inertial Fusion experiments conducted on the Z machine at Sandia National Laboratories. We show that in these experiments BR ≈ 0.34(+0.14/−0.06) MG · cm, a ∼ 14× increase in BR from the initial value, and confirming that the DD-fusion tritons are magnetized at stagnation. This is the first experimental verification of charged burn product magnetization facilitated by compression of an initial seed magnetic flux.

  17. Effects of magnetization on fusion product trapping and secondary neutron spectra

    DOE PAGES

    Knapp, Patrick F.; Schmit, Paul F.; Hansen, Stephanie B.; ...

    2015-05-14

    In magnetizing the fusion fuel in inertial confinement fusion (ICF) systems, we found that the required stagnation pressure and density can be relaxed dramatically. This happens because the magnetic field insulates the hot fuel from the cold pusher and traps the charged fusion burn products. This trapping allows the burn products to deposit their energy in the fuel, facilitating plasma self-heating. Here, we report on a comprehensive theory of this trapping in a cylindrical DD plasma magnetized with a purely axial magnetic field. Using this theory, we are able to show that the secondary fusion reactions can be used tomore » infer the magnetic field-radius product, BR, during fusion burn. This parameter, not ρR, is the primary confinement parameter in magnetized ICF. Using this method, we analyze data from recent Magnetized Liner InertialFusion experiments conducted on the Z machine at Sandia National Laboratories. Furthermore, we show that in these experiments BR ≈ 0.34(+0.14/-0.06) MG · cm, a ~ 14× increase in BR from the initial value, and confirming that the DD-fusion tritons are magnetized at stagnation. Lastly, this is the first experimental verification of charged burn product magnetization facilitated by compression of an initial seed magnetic flux.« less

  18. Effects of magnetization on fusion product trapping and secondary neutron spectraa)

    NASA Astrophysics Data System (ADS)

    Knapp, P. F.; Schmit, P. F.; Hansen, S. B.; Gomez, M. R.; Hahn, K. D.; Sinars, D. B.; Peterson, K. J.; Slutz, S. A.; Sefkow, A. B.; Awe, T. J.; Harding, E.; Jennings, C. A.; Desjarlais, M. P.; Chandler, G. A.; Cooper, G. W.; Cuneo, M. E.; Geissel, M.; Harvey-Thompson, A. J.; Porter, J. L.; Rochau, G. A.; Rovang, D. C.; Ruiz, C. L.; Savage, M. E.; Smith, I. C.; Stygar, W. A.; Herrmann, M. C.

    2015-05-01

    By magnetizing the fusion fuel in inertial confinement fusion (ICF) systems, the required stagnation pressure and density can be relaxed dramatically. This happens because the magnetic field insulates the hot fuel from the cold pusher and traps the charged fusion burn products. This trapping allows the burn products to deposit their energy in the fuel, facilitating plasma self-heating. Here, we report on a comprehensive theory of this trapping in a cylindrical DD plasma magnetized with a purely axial magnetic field. Using this theory, we are able to show that the secondary fusion reactions can be used to infer the magnetic field-radius product, BR, during fusion burn. This parameter, not ρR, is the primary confinement parameter in magnetized ICF. Using this method, we analyze data from recent Magnetized Liner Inertial Fusion experiments conducted on the Z machine at Sandia National Laboratories. We show that in these experiments BR ≈ 0.34(+0.14/-0.06) MG . cm, a ˜ 14× increase in BR from the initial value, and confirming that the DD-fusion tritons are magnetized at stagnation. This is the first experimental verification of charged burn product magnetization facilitated by compression of an initial seed magnetic flux.

  19. Unusual Fusion Proteins of HIV-1

    PubMed Central

    Langer, Simon; Sauter, Daniel

    2017-01-01

    Despite its small genome size, the Human Immunodeficiency Virus 1 (HIV-1) is one of the most successful pathogens and has infected more than 70 million people worldwide within the last decades. In total, HIV-1 expresses 16 canonical proteins from only nine genes within its 10 kb genome. Expression of the structural genes gag, pol, and env, the regulatory genes rev and tat and the accessory genes vpu, nef, vpr, and vif enables assembly of the viral particle, regulates viral gene transcription, and equips the virus to evade or counteract host immune responses. In addition to the canonically expressed proteins, a growing number of publications describe the existence of non-canonical fusion proteins in HIV-1 infected cells. Most of them are encoded by the tat-env-rev locus. While the majority of these fusion proteins (e.g., TNV/p28tev, p186Drev, Tat1-Rev2, Tat^8c, p17tev, or Ref) are the result of alternative splicing events, Tat-T/Vpt is produced upon programmed ribosomal frameshifting, and a Rev1-Vpu fusion protein is expressed due to a nucleotide polymorphism that is unique to certain HIV-1 clade A and C strains. A better understanding of the expression and activity of these non-canonical viral proteins will help to dissect their potential role in viral replication and reveal how HIV-1 optimized the coding potential of its genes. The goal of this review is to provide an overview of previously described HIV-1 fusion proteins and to summarize our current knowledge of their expression patterns and putative functions. PMID:28119676

  20. Kinetic Modeling of Laser-Induced Fusion

    DTIC Science & Technology

    2007-09-01

    Thermal neutrons are of considerable interest to the Department of Defense and for commercial applications. Unlike high- energy photons, neutrons easily...develop a compact generator for thermal neutrons with large enough flux. The limited availability of radio-isotopes, combined with the relatively...Deuterium-Tritium (D-T) fusion, which generates Alpha particles and fast neutrons . In these sources, Deuterium ions are accelerated to about 130 keV and hit

  1. Overview of the RFX fusion science program

    NASA Astrophysics Data System (ADS)

    Martin, P.; Adamek, J.; Agostinetti, P.; Agostini, M.; Alfier, A.; Angioni, C.; Antoni, V.; Apolloni, L.; Auriemma, F.; Barana, O.; Barison, S.; Baruzzo, M.; Bettini, P.; Boldrin, M.; Bolzonella, T.; Bonfiglio, D.; Bonomo, F.; Boozer, A. H.; Brombin, M.; Brotankova, J.; Buffa, A.; Canton, A.; Cappello, S.; Carraro, L.; Cavazzana, R.; Cavinato, M.; Chacon, L.; Chitarin, G.; Cooper, W. A.; Dal Bello, S.; Dalla Palma, M.; Delogu, R.; De Lorenzi, A.; De Masi, G.; Dong, J. Q.; Drevlak, M.; Escande, D. F.; Fantini, F.; Fassina, A.; Fellin, F.; Ferro, A.; Fiameni, S.; Fiorentin, A.; Franz, P.; Gaio, E.; Garbet, X.; Gazza, E.; Giudicotti, L.; Gnesotto, F.; Gobbin, M.; Grando, L.; Guo, S. C.; Hirano, Y.; Hirshman, S. P.; Ide, S.; Igochine, V.; In, Y.; Innocente, P.; Kiyama, S.; Liu, S. F.; Liu, Y. Q.; Lòpez Bruna, D.; Lorenzini, R.; Luchetta, A.; Manduchi, G.; Mansfield, D. K.; Marchiori, G.; Marcuzzi, D.; Marrelli, L.; Martini, S.; Matsunaga, G.; Martines, E.; Mazzitelli, G.; McCollam, K.; Menmuir, S.; Milani, F.; Momo, B.; Moresco, M.; Munaretto, S.; Novello, L.; Okabayashi, M.; Ortolani, S.; Paccagnella, R.; Pasqualotto, R.; Pavei, M.; Perverezev, G. V.; Peruzzo, S.; Piovan, R.; Piovesan, P.; Piron, L.; Pizzimenti, A.; Pomaro, N.; Pomphrey, N.; Predebon, I.; Puiatti, M. E.; Rigato, V.; Rizzolo, A.; Rostagni, G.; Rubinacci, G.; Ruzzon, A.; Sakakita, H.; Sanchez, R.; Sarff, J. S.; Sattin, F.; Scaggion, A.; Scarin, P.; Schneider, W.; Serianni, G.; Sonato, P.; Spada, E.; Soppelsa, A.; Spagnolo, S.; Spolaore, M.; Spong, D. A.; Spizzo, G.; Takechi, M.; Taliercio, C.; Terranova, D.; Toigo, V.; Valisa, M.; Veranda, M.; Vianello, N.; Villone, F.; Wang, Z.; White, R. B.; Yadikin, D.; Zaccaria, P.; Zamengo, A.; Zanca, P.; Zaniol, B.; Zanotto, L.; Zilli, E.; Zollino, G.; Zuin, M.

    2011-09-01

    This paper summarizes the main achievements of the RFX fusion science program in the period between the 2008 and 2010 IAEA Fusion Energy Conferences. RFX-mod is the largest reversed field pinch in the world, equipped with a system of 192 coils for active control of MHD stability. The discovery and understanding of helical states with electron internal transport barriers and core electron temperature >1.5 keV significantly advances the perspectives of the configuration. Optimized experiments with plasma current up to 1.8 MA have been realized, confirming positive scaling. The first evidence of edge transport barriers is presented. Progress has been made also in the control of first-wall properties and of density profiles, with initial first-wall lithization experiments. Micro-turbulence mechanisms such as ion temperature gradient and micro-tearing are discussed in the framework of understanding gradient-driven transport in low magnetic chaos helical regimes. Both tearing mode and resistive wall mode active control have been optimized and experimental data have been used to benchmark numerical codes. The RFX programme also provides important results for the fusion community and in particular for tokamaks and stellarators on feedback control of MHD stability and on three-dimensional physics. On the latter topic, the result of the application of stellarator codes to describe three-dimensional reversed field pinch physics will be presented.

  2. Heat capacity of poly(trimethylene terephthalate)

    SciTech Connect

    Pyda, M.; Boller, A.; Wunderlich, B. |; Grebowicz, J.; Chuah, H.

    1997-12-01

    Thermal analysis of poly(trimethylene terephthalate) (PTT) has been carried out using standard differential scanning calorimetry and temperature-modulated differential scanning calorimetry. Heat capacities of the solid and liquid states of semicrystalline PTT are reported from 190 K to 570 K. The semicrystalline PTT has a glass transition temperature of about 331 K. Between 460 K and 480 K, PTT shows an exothermic ordering. The melting endotherm occurs between 480 K and 505 K with an onset temperature of 489.15 K (216 C). The heat of fusion of typical semicrystalline samples is 13.8 kJ/mol. For 100% crystalline PTT the heat of fusion is estimated to be 28--30 kJ/mol. The heat capacity of solid PTT is linked to an approximate group vibrational spectrum, and the Tarasov equation is used to estimate the skeletal vibrational heat capacity ({Theta}{sub 1} = 542 K and {Theta}{sub 3} = 42 K). A comparison of calculation and experimental heat capacities show agreement of better than {+-}2% between 190--300 K. The experimental heat capacity of liquid PTT can be expressed as a linear function of temperature: C{sub p} {sup L}(exp) = 211.6 + 0.434 T J/(K mol) and compares well with estimations from the ATHAS data bank using group contributions of other polymers with the same constituent groups ({+-} 0.5%). The change of heat capacity at T{sub g} of amorphous PTT has been estimated from the heat capacities of liquid and solid to be 86.4 J/(K mol). Knowing C{sub p} of the solid, liquid, and the transition parameters, the thermodynamic functions: enthalpy, entropy and Gibbs function were obtained.

  3. Heat pump augmentation of nuclear process heat

    SciTech Connect

    Koutz, S.L.

    1986-03-18

    A system is described for increasing the temperature of a working fluid heated by a nuclear reactor. The system consists of: a high temperature gas cooled nuclear reactor having a core and a primary cooling loop through which a coolant is circulated so as to undergo an increase in temperature, a closed secondary loop having a working fluid therein, the cooling and secondary loops having cooperative association with an intermediate heat exchanger adapted to effect transfer of heat from the coolant to the working fluid as the working fluid passes through the intermediate heat exchanger, a heat pump connected in the secondary loop and including a turbine and a compressor through which the working fluid passes so that the working fluid undergoes an increase in temperature as it passes through the compressor, a process loop including a process chamber adapted to receive a process fluid therein, the process chamber being connected in circuit with the secondary loop so as to receive the working fluid from the compressor and transfer heat from the working fluid to the process fluid, a heat exchanger for heating the working fluid connected to the process loop for receiving heat therefrom and for transferring heat to the secondary loop prior to the working fluid passing through the compressor, the secondary loop being operative to pass the working fluid from the process chamber to the turbine so as to effect driving relation thereof, a steam generator operatively associated with the secondary loop so as to receive the working fluid from the turbine, and a steam loop having a feedwater supply and connected in circuit with the steam generator so that feedwater passing through the steam loop is heated by the steam generator, the steam loop being connected in circuit with the process chamber and adapted to pass steam to the process chamber with the process fluid.

  4. Choice of coils for a fusion reactor

    PubMed Central

    Alexander, Romeo; Garabedian, Paul R.

    2007-01-01

    In a fusion reactor a hot plasma of deuterium and tritium is confined by a strong magnetic field to produce helium ions and release energetic neutrons. The 3D geometry of a stellarator provides configurations for such a device that reduce net toroidal current that might lead to disruptions. We construct smooth coils generating an external magnetic field designed to prevent the plasma from deteriorating. PMID:17640879

  5. Crystal Structure of the Pre-fusion Nipah Virus Fusion Glycoprotein Reveals a Novel Hexamer-of-Trimers Assembly

    PubMed Central

    Dutta, Somnath; Yan, Lianying; Feng, YanRu; Wang, Lin-Fa; Skiniotis, Georgios; Lee, Benhur; Zhou, Z. Hong; Broder, Christopher C.; Aguilar, Hector C.; Nikolov, Dimitar B.

    2015-01-01

    Nipah virus (NiV) is a paramyxovirus that infects host cells through the coordinated efforts of two envelope glycoproteins. The G glycoprotein attaches to cell receptors, triggering the fusion (F) glycoprotein to execute membrane fusion. Here we report the first crystal structure of the pre-fusion form of the NiV-F glycoprotein ectodomain. Interestingly this structure also revealed a hexamer-of-trimers encircling a central axis. Electron tomography of Nipah virus-like particles supported the hexameric pre-fusion model, and biochemical analyses supported the hexamer-of-trimers F assembly in solution. Importantly, structure-assisted site-directed mutagenesis of the interfaces between F trimers highlighted the functional relevance of the hexameric assembly. Shown here, in both cell-cell fusion and virus-cell fusion systems, our results suggested that this hexamer-of-trimers assembly was important during fusion pore formation. We propose that this assembly would stabilize the pre-fusion F conformation prior to cell attachment and facilitate the coordinated transition to a post-fusion conformation of all six F trimers upon triggering of a single trimer. Together, our data reveal a novel and functional pre-fusion architecture of a paramyxoviral fusion glycoprotein. PMID:26646856

  6. A quasi-optical electron cyclotron maser for fusion reactor heating. Final report

    SciTech Connect

    Morse, E.C.

    1990-12-31

    High power microwave and millimeter sources, such as the quasi-optical electron cyclotron maser (QOECM) are important in fusion research as well as in high-energy physics and in other applications. The interaction between the electromagnetic modes of a Fabry-Perot resonator and an electron beam gyrating through a magnetic field has been studied for both the cases of beams parallel and perpendicular to the resonator. The parallel case was theoretically first studied by Kurin for forward and backward wave interaction, and experimentally by Komlev and Kurin. Kreischer and Temkin reviewed the general case of the linear small signal interaction parallel and perpendicular to the resonator. Sprangle, et al discussed the perpendicular case in a self-consistent linear and nonlinear theoretical study using the Gaussian transverse profile of an open resonator with a single longitudinal mode. Experimental verification of the devices operation was first mentioned in work at the Naval Research Laboratory. Theoretical studies using a time-dependent analysis of a large number of longitudinal modes with similar transverse mode profiles have demonstrated that single longitudinal-mode operation can be achieved at equilibrium and that performance can be enhanced by prebunching the electron beam and tapering the magnetic field. The use of output coupling apertures in the mirrors has been studied theoretically in relation to the structure of the modes for both confocal and nonconfocal resonators by Permnoud; use of an open resonator with stepped mirrors has been studied in order to choose a particular longitudinal mode. Studies at the Naval Research Laboratory mirror used configurations that diffraction couple the energy from around the mirror edges, so that the transverse profile inside the resonator can be selective to the fundamental mode.

  7. A quasi-optical electron cyclotron maser for fusion reactor heating

    SciTech Connect

    Morse, E.C.

    1990-01-01

    High power microwave and millimeter sources, such as the quasi-optical electron cyclotron maser (QOECM) are important in fusion research as well as in high-energy physics and in other applications. The interaction between the electromagnetic modes of a Fabry-Perot resonator and an electron beam gyrating through a magnetic field has been studied for both the cases of beams parallel and perpendicular to the resonator. The parallel case was theoretically first studied by Kurin for forward and backward wave interaction, and experimentally by Komlev and Kurin. Kreischer and Temkin reviewed the general case of the linear small signal interaction parallel and perpendicular to the resonator. Sprangle, et al discussed the perpendicular case in a self-consistent linear and nonlinear theoretical study using the Gaussian transverse profile of an open resonator with a single longitudinal mode. Experimental verification of the devices operation was first mentioned in work at the Naval Research Laboratory. Theoretical studies using a time-dependent analysis of a large number of longitudinal modes with similar transverse mode profiles have demonstrated that single longitudinal-mode operation can be achieved at equilibrium and that performance can be enhanced by prebunching the electron beam and tapering the magnetic field. The use of output coupling apertures in the mirrors has been studied theoretically in relation to the structure of the modes for both confocal and nonconfocal resonators by Permnoud; use of an open resonator with stepped mirrors has been studied in order to choose a particular longitudinal mode. Studies at the Naval Research Laboratory mirror used configurations that diffraction couple the energy from around the mirror edges, so that the transverse profile inside the resonator can be selective to the fundamental mode.

  8. N-learners problem: Fusion of concepts

    SciTech Connect

    Rao, N.S.V.; Oblow, E.M.; Glover, C.W.; liepins, G.E. . Dept. of Computer Science)

    1991-09-01

    We are given N learners each capable of learning concepts (subsets) of a domain set X in the sense of Valiant, i.e. for any c {element of} C {improper subset} 2{sup X}, given a finite set of examples of the form < x{sub 1}, M{sub c}(x{sub 1}) >; < x{sub 2}, M{sub c}(x{sub 2}) >;...;< x{sub 1}, M{sub c}(x{sub 1}) > generated according to an unknown probability distribution P{sub X} on X, each learner produces a close approximation to c with a high probability. We are interested in combining the N learners using a single fuser or consolidator. We consider the paradigm of passive fusion, where each learner is first trained with the sample without the influence of the consolidator. The composite system is constituted by the fuser and the individual learners. We consider two cases: open and closed fusion. In open fusion the fuser is given the sample and the hypotheses of the individual learners; we show that the fusion rule can be obtained by formulating this problem as another learning problem. For the case all individual learners are trained with the same sample, we show sufficiency conditions that ensure the composite system to be better than the best of the individual: the hypothesis space of the consolidator (a) satisfies the isolation property of degree at least N, and (b) has Vapnik-Chervonenkis dimension less than or equal to that of every individual learner. If individual learners are trained by independently generated samples, we obtain a much weaker bound on the VC-dimension of the hypothesis space of the fuser. Second, in closed fusion the fuser does not have an access to either the training sample or the hypotheses of the individual learners. By suitable designing a linear threshold function of the outputs of individual learners, we show that the composite system can be made better than the best of the learners.

  9. Spinal Fusion

    MedlinePlus

    ... concept of fusion is similar to that of welding in industry. Spinal fusion surgery, however, does not ... bone taken from the patient has a long history of use and results in predictable healing. Autograft ...

  10. Fusion 2.0: The Next Generation of Fusion in California: Aligning State and Regional Fusion Centers

    DTIC Science & Technology

    2010-03-01

    again and bring their friends.” ( Walt Disney ) Succinctly put, the way fusion centers can maintain support and sustainability in today’s political...success just hours later at the Battle of Lexington. More than 226 years later, millions of Americans and people throughout the world would watch in... World Trade Center and Pentagon, killing thousands in the aftermath. Regrettably, there would be no modern day Paul Revere to warn of these attacks

  11. Oral cancer/endothelial cell fusion experiences nuclear fusion and acquisition of enhanced survival potential

    SciTech Connect

    Song, Kai; Song, Yong; Zhao, Xiao-Ping; Shen, Hui; Wang, Meng; Yan, Ting-lin; Liu, Ke; Shang, Zheng-jun

    2014-10-15

    Most previous studies have linked cancer–macrophage fusion with tumor progression and metastasis. However, the characteristics of hybrid cells derived from oral cancer and endothelial cells and their involvement in cancer remained unknown. Double-immunofluorescent staining and fluorescent in situ hybridization (FISH) were performed to confirm spontaneous cell fusion between eGFP-labeled human umbilical vein endothelial cells (HUVECs) and RFP-labeled SCC9, and to detect the expression of vementin and cytokeratin 18 in the hybrids. The property of chemo-resistance of such hybrids was examined by TUNEL assay. The hybrid cells in xenografted tumor were identified by FISH and GFP/RFP dual-immunofluoresence staining. We showed that SCC9 cells spontaneously fused with cocultured endothelial cells, and the resultant hybrid cells maintained the division and proliferation activity after re-plating and thawing. Such hybrids expressed markers of both parental cells and became more resistant to chemotherapeutic drug cisplatin as compared to the parental SCC9 cells. Our in vivo data indicated that the hybrid cells contributed to tumor composition by using of immunostaining and FISH analysis, even though the hybrid cells and SCC9 cells were mixed with 1:10,000, according to the FACS data. Our study suggested that the fusion events between oral cancer and endothelial cells undergo nuclear fusion and acquire a new property of drug resistance and consequently enhanced survival potential. These experimental findings provide further supportive evidence for the theory that cell fusion is involved in cancer progression. - Highlights: • The fusion events between oral cancer and endothelial cells undergo nuclear fusion. • The resulting hybrid cells acquire a new property of drug resistance. • The resulting hybrid cells express the markers of both parental cells (i.e. vimentin and cytokeratin 18). • The hybrid cells contribute to tumor repopulation in vivo.

  12. Uncertainty assessment of enthalpy of fusion measurements performed by using an improved Calvet calorimeter

    NASA Astrophysics Data System (ADS)

    Razouk, Refat; Hay, Bruno; Himbert, Marc

    2015-10-01

    The French National Metrology Institute LNE-LCM has developed a new in situ electrical calibration system which is integrated into a heat flux Calvet calorimeter in order to perform accurate and reliable measurements of enthalpy of fusion from 23 °C to 1000 °C. The measurement procedure consists in putting a sample inside the calibration system and in performing the heat calibration of the calorimeter by electrical substitution (Joule effect) before and after the enthalpy of fusion measurement during the same heating run. This procedure directly takes into account the temperature dependence of the calibration factor (sensitivity) and keeps the calibration and measurement experimental conditions strictly the same. Uncertainties of the enthalpy of fusion measurements, performed by using this facility and procedure, have been assessed according to the ‘guide to the expression of uncertainty in measurement’. The detailed uncertainty budgets are presented here in the case of three pure metallic materials (indium, tin and silver). The relative expanded uncertainty (k  =  2) of the enthalpy of fusion measurement is estimated to be less than 0.4% for the high purity indium and tin, and less than 1% in the case of silver.

  13. The ignition design space of magnetized target fusion

    SciTech Connect

    Lindemuth, Irvin R.

    2015-12-15

    The simple magnetized target implosion model of Lindemuth and Kirkpatrick [Nucl. Fusion 23, 263 (1983)] has been extended to survey the potential parameter space in which three types of magnetized targets—cylindrical with axial magnetic field, cylindrical with azimuthal magnetic field, and spherical with azimuthal magnetic field—might achieve ignition and produce large gain at achievable radial convergence ratios. The model has been used to compute the dynamic, time-dependent behavior of many initial parameter sets that have been based upon projected ignition conditions using the quasi-adiabatic and quasi-flux-conserving properties of magnetized target implosions. The time-dependent calculations have shown that energy gains greater than 30 can potentially be achieved for each type of target. By example, it is shown that high gain may be obtained at extremely low convergence ratios, e.g., less than 15, for appropriate initial conditions. It is also shown that reaching the ignition condition, i.e., when fusion deposition rates equal total loss rates, does not necessarily lead to high gain and high fuel burn-up. At the lower densities whereby fusion temperatures can be reached in magnetized targets, the fusion burn rate may be only comparable with the hydrodynamic heating/cooling rates. On the other hand, when the fusion burn rates significantly exceed the hydrodynamic rates, the calculations show a characteristic rapid increase in temperature due to alpha particle deposition with a subsequent increased burn rate and high gain. A major result of this paper is that each type of target operates in a different initial density-energy-velocity range. The results of this paper provide initial target plasma parameters and driver parameters that can be used to guide plasma formation and driver development for magnetized targets. The results indicate that plasmas for spherical, cylindrical with azimuthal field, and cylindrical with axial field targets must have an initial

  14. The ignition design space of magnetized target fusion

    NASA Astrophysics Data System (ADS)

    Lindemuth, Irvin R.

    2015-12-01

    The simple magnetized target implosion model of Lindemuth and Kirkpatrick [Nucl. Fusion 23, 263 (1983)] has been extended to survey the potential parameter space in which three types of magnetized targets—cylindrical with axial magnetic field, cylindrical with azimuthal magnetic field, and spherical with azimuthal magnetic field—might achieve ignition and produce large gain at achievable radial convergence ratios. The model has been used to compute the dynamic, time-dependent behavior of many initial parameter sets that have been based upon projected ignition conditions using the quasi-adiabatic and quasi-flux-conserving properties of magnetized target implosions. The time-dependent calculations have shown that energy gains greater than 30 can potentially be achieved for each type of target. By example, it is shown that high gain may be obtained at extremely low convergence ratios, e.g., less than 15, for appropriate initial conditions. It is also shown that reaching the ignition condition, i.e., when fusion deposition rates equal total loss rates, does not necessarily lead to high gain and high fuel burn-up. At the lower densities whereby fusion temperatures can be reached in magnetized targets, the fusion burn rate may be only comparable with the hydrodynamic heating/cooling rates. On the other hand, when the fusion burn rates significantly exceed the hydrodynamic rates, the calculations show a characteristic rapid increase in temperature due to alpha particle deposition with a subsequent increased burn rate and high gain. A major result of this paper is that each type of target operates in a different initial density-energy-velocity range. The results of this paper provide initial target plasma parameters and driver parameters that can be used to guide plasma formation and driver development for magnetized targets. The results indicate that plasmas for spherical, cylindrical with azimuthal field, and cylindrical with axial field targets must have an initial

  15. Comparison of additive image fusion vs. feature-level image fusion techniques for enhanced night driving

    NASA Astrophysics Data System (ADS)

    Bender, Edward J.; Reese, Colin E.; Van Der Wal, Gooitzen S.

    2003-02-01

    The Night Vision & Electronic Sensors Directorate (NVESD) has conducted a series of image fusion evaluations under the Head-Tracked Vision System (HTVS) program. The HTVS is a driving system for both wheeled and tracked military vehicles, wherein dual-waveband sensors are directed in a more natural head-slewed imaging mode. The HTVS consists of thermal and image-intensified TV sensors, a high-speed gimbal, a head-mounted display, and a head tracker. A series of NVESD field tests over the past two years has investigated the degree to which additive (A+B) image fusion of these sensors enhances overall driving performance. Additive fusion employs a single (but user adjustable) fractional weighting for all the features of each sensor's image. More recently, NVESD and Sarnoff Corporation have begun a cooperative effort to evaluate and refine Sarnoff's "feature-level" multi-resolution (pyramid) algorithms for image fusion. This approach employs digital processing techniques to select at each image point only the sensor with the strongest features, and to utilize only those features to reconstruct the fused video image. This selection process is performed simultaneously at multiple scales of the image, which are combined to form the reconstructed fused image. All image fusion techniques attempt to combine the "best of both sensors" in a single image. Typically, thermal sensors are better for detecting military threats and targets, while image-intensified sensors provide more natural scene cues and detect cultural lighting. This investigation will address the differences between additive fusion and feature-level image fusion techniques for enhancing the driver's overall situational awareness.

  16. Direct observation of intermediate states in model membrane fusion

    NASA Astrophysics Data System (ADS)

    Keidel, Andrea; Bartsch, Tobias F.; Florin, Ernst-Ludwig

    2016-03-01

    We introduce a novel assay for membrane fusion of solid supported membranes on silica beads and on coverslips. Fusion of the lipid bilayers is induced by bringing an optically trapped bead in contact with the coverslip surface while observing the bead’s thermal motion with microsecond temporal and nanometer spatial resolution using a three-dimensional position detector. The probability of fusion is controlled by the membrane tension on the particle. We show that the progression of fusion can be monitored by changes in the three-dimensional position histograms of the bead and in its rate of diffusion. We were able to observe all fusion intermediates including transient fusion, formation of a stalk, hemifusion and the completion of a fusion pore. Fusion intermediates are characterized by axial but not lateral confinement of the motion of the bead and independently by the change of its rate of diffusion due to the additional drag from the stalk-like connection between the two membranes. The detailed information provided by this assay makes it ideally suited for studies of early events in pure lipid bilayer fusion or fusion assisted by fusogenic molecules.

  17. Myomaker: A membrane activator of myoblast fusion and muscle formation

    PubMed Central

    Millay, Douglas P.; O’Rourke, Jason R.; Sutherland, Lillian B.; Bezprozvannaya, Svetlana; Shelton, John M.; Bassel-Duby, Rhonda; Olson, Eric N.

    2013-01-01

    Summary Fusion of myoblasts is essential for the formation of multi-nucleated muscle fibers. However, the identity of myogenic proteins that directly govern this fusion process has remained elusive. Here, we discovered a muscle-specific membrane protein, named Myomaker, that controls myoblast fusion. Myomaker is expressed on the cell surface of myoblasts during fusion and is down-regulated thereafter. Over-expression of Myomaker in myoblasts dramatically enhances fusion and genetic disruption of Myomaker in mice causes perinatal death due to an absence of multi-nucleated muscle fibers. Remarkably, forced expression of Myomaker in fibroblasts promotes fusion with myoblasts, demonstrating the direct participation of this protein in the fusion process. Pharmacologic perturbation of the actin cytoskeleton abolishes the activity of Myomaker, consistent with prior studies implicating actin dynamics in myoblast fusion. These findings reveal a long-sought myogenic fusion protein both necessary and sufficient for mammalian myoblast fusion and provide new insights into the molecular underpinnings of muscle formation. PMID:23868259

  18. Limitation of heavy-ion fusion: Fusion of aligned /sup 23/Na with /sup 23/Na

    SciTech Connect

    Blatt, K.; Becker, K.; Heck, B.; Jaensch, H.; Leucker, H.; Fick, D.; Chacekaplar, R.; Butsch, R.; Kraemer, D.; Moebius, K.h.

    1986-08-18

    The excitation function for fusion of /sup 23/Na with /sup 23/Na was measured in the energy range 40 less than or equal to E/sub c.m./less than or equal to 88.5 MeV. Additionally the tensor analyzing power T/sub 20/ was determined to be T/sub 20/ = -0.0060 +- 0.0125 at E/sub c.m./ = 85 MeV. The results are discussed in terms of an entrance-channel versus a compound-nucleus model for the observed limitation of fusion. A typical entrance-channel model, the surface-friction model, which is able to describe all fusion excitation functions leading to /sup 46/Ti, fails to reproduce the observed value of T/sub 20/. The data are consistent, on the other hand, with the compound-nucleus interpretation.

  19. Qubit-loss-free fusion of W states

    NASA Astrophysics Data System (ADS)

    Li, Ke; Kong, Fan-Zhen; Yang, Ming; Yang, Qing; Cao, Zhuo-Liang

    2016-12-01

    Fusion technique plays a key role in the preparation of large-scale W states, but the currently existing fusion schemes are suffering from the qubit loss problem, i.e., the number of the output entangled qubits is smaller than the sum of numbers of the input entangled qubits, which will inevitably decrease the fusion efficiency and increase the number of fusion steps as well as the requirement of quantum memories. In this paper, we design a fusion mechanism to fuse two small-size W states into a large-scale W state without qubit loss, and thus we call it qubit-loss-free (QLF) fusion mechanism. This QLF fusion mechanism is based on a two-outcome positive-operator valued measurement on two qubits extracting from two small-size W states, and works for both pure and mixed W states. The QLF nature of this fusion mechanism clearly increases the final size of the obtained W state, and greatly reduces the number of fusion steps as well as the requirement of quantum memories required to achieve a W state of a target size, so it is more efficient and feasible than the currently existing fusion schemes. There is no complete failure output in our QLF fusion scheme, and all the garbage states are recyclable. Two example schemes are proposed to realize this QLF fusion mechanism in a cavity quantum electrodynamics system and three-qubit Heisenberg XYZ model, respectively, which demonstrates the possibility of the physical realization of this QLF fusion mechanism.

  20. Optical imaging of cell fusion and fusion proteins in Caenorhabditis elegans.

    PubMed

    Ems, Star; Mohler, William A

    2008-01-01

    Cell fusion is a very dynamic process in which the entire membrane and cellular contents of two or more cells merge into one. Strategies developed to understand the component processes that make up a full fusion event require imaging to be performed over a range of space and time scales. These strategies must cover detection of nanometer-sized pores, monitoring cytoplasmic diffusion and the dynamic localization of proteins that induce fusion competence, and three-dimensional reconstruction of multinucleated cells. Caenorhabditis elegans' small size, predictable development, and transparent body make this organism optimal for microscopic investigations. In this chapter, focus is placed on light microscopy techniques that have been used thus far to study developmental fusion events in C. elegans and the insights that have been gained from them. There is also a general overview of the developmental timing of the cell fusion events. Additionally, several protocols are described for preparing both fixed and live specimens at various developmental stages of C. elegans for examination via optical microscopy.

  1. Repair welding of fusion reactor components. Final technical report

    SciTech Connect

    Chin, B.A.; Wang, C.A.

    1997-09-30

    The exposure of metallic materials, such as structural components of the first wall and blanket of a fusion reactor, to neutron irradiation will induce changes in both the material composition and microstructure. Along with these changes can come a corresponding deterioration in mechanical properties resulting in premature failure. It is, therefore, essential to expect that the repair and replacement of the degraded components will be necessary. Such repairs may require the joining of irradiated materials through the use of fusion welding processes. The present ITER (International Thermonuclear Experimental Reactor) conceptual design is anticipated to have about 5 km of longitudinal welds and ten thousand pipe butt welds in the blanket structure. A recent study by Buende et al. predict that a failure is most likely to occur in a weld. The study is based on data from other large structures, particularly nuclear reactors. The data used also appear to be consistent with the operating experience of the Fast Flux Test Facility (FFTF). This reactor has a fuel pin area comparable with the area of the ITER first wall and has experienced one unanticipated fuel pin failure after two years of operation. The repair of irradiated structures using fusion welding will be difficult due to the entrapped helium. Due to its extremely low solubility in metals, helium will diffuse and agglomerate to form helium bubbles after being trapped at point defects, dislocations, and grain boundaries. Welding of neutron-irradiated type 304 stainless steels has been reported with varying degree of heat-affected zone cracking (HAZ). The objectives of this study were to determine the threshold helium concentrations required to cause HAZ cracking and to investigate techniques that might be used to eliminate the HAZ cracking in welding of helium-containing materials.

  2. A neutron study of the feline leukaemia virus fusion peptide: Implications for biological fusion?

    NASA Astrophysics Data System (ADS)

    Davies, Sarah M. A.; Darkes, Malcolm J. M.; Bradshaw, Jeremy P.

    Neutron diffraction studies were performed on stacked phospholipid bilayers to determine the effects of the feline leukaemia virus (FeLV) fusion peptide on membrane structure. Bilayers were composed of dioleoylphosphatidylcholine with 50% (mol) dioleoylphosphatidylglycerol. Neutron scattering profiles with peptide present showed an increase in scattering density in the lipid-tails region, whilst scattering by the lipid headgroup region was decreased. This is interpreted as a lowering of the packing density of the lipid headgroups and an increase in the packing density of the lipid tails. Modelling studies and experimental evidence have suggested that fusion peptides catalyse fusion by increasing the negative curvature of the target membrane's outer monolayer. Our results presented here add support to this hypothesis for the fusion mechanism. The 2H 2O scattering profile was also slightly perturbed in the lipid headgroup region with 1% (mol)FeLV fusion peptide present. The FeLV peptide had no significant effect on the organisation of bilayers containing only dioleoylphosphatidylcholine.

  3. Oral cancer/endothelial cell fusion experiences nuclear fusion and acquisition of enhanced survival potential.

    PubMed

    Song, Kai; Song, Yong; Zhao, Xiao-Ping; Shen, Hui; Wang, Meng; Yan, Ting-Lin; Liu, Ke; Shang, Zheng-Jun

    2014-10-15

    Most previous studies have linked cancer-macrophage fusion with tumor progression and metastasis. However, the characteristics of hybrid cells derived from oral cancer and endothelial cells and their involvement in cancer remained unknown. Double-immunofluorescent staining and fluorescent in situ hybridization (FISH) were performed to confirm spontaneous cell fusion between eGFP-labeled human umbilical vein endothelial cells (HUVECs) and RFP-labeled SCC9, and to detect the expression of vementin and cytokeratin 18 in the hybrids. The property of chemo-resistance of such hybrids was examined by TUNEL assay. The hybrid cells in xenografted tumor were identified by FISH and GFP/RFP dual-immunofluoresence staining. We showed that SCC9 cells spontaneously fused with cocultured endothelial cells, and the resultant hybrid cells maintained the division and proliferation activity after re-plating and thawing. Such hybrids expressed markers of both parental cells and became more resistant to chemotherapeutic drug cisplatin as compared to the parental SCC9 cells. Our in vivo data indicated that the hybrid cells contributed to tumor composition by using of immunostaining and FISH analysis, even though the hybrid cells and SCC9 cells were mixed with 1:10,000, according to the FACS data. Our study suggested that the fusion events between oral cancer and endothelial cells undergo nuclear fusion and acquire a new property of drug resistance and consequently enhanced survival potential. These experimental findings provide further supportive evidence for the theory that cell fusion is involved in cancer progression.

  4. Impact properties of 500-kg heat of V-4Cr-4Ti

    SciTech Connect

    Chung, H.M.; Nowicki, L.; Gazda, J.

    1995-04-01

    Following previous reports of excellent properties of a laboratory heat of V-4Cr-4Ti, the alloy identified as the primary vanadium-based candidate for application as fusion reactor structural components, a large industrial-scale (500-kg) heat of the alloy was fabricated successfully. The objective of this work is to determine the impact properties of the industrial-scale heat.

  5. Optimization of Heat Exchangers

    SciTech Connect

    Ivan Catton

    2010-10-01

    The objective of this research is to develop tools to design and optimize heat exchangers (HE) and compact heat exchangers (CHE) for intermediate loop heat transport systems found in the very high temperature reator (VHTR) and other Generation IV designs by addressing heat transfer surface augmentation and conjugate modeling. To optimize heat exchanger, a fast running model must be created that will allow for multiple designs to be compared quickly. To model a heat exchanger, volume averaging theory, VAT, is used. VAT allows for the conservation of mass, momentum and energy to be solved for point by point in a 3 dimensional computer model of a heat exchanger. The end product of this project is a computer code that can predict an optimal configuration for a heat exchanger given only a few constraints (input fluids, size, cost, etc.). As VAT computer code can be used to model characteristics )pumping power, temperatures, and cost) of heat exchangers more quickly than traditional CFD or experiment, optimization of every geometric parameter simultaneously can be made. Using design of experiment, DOE and genetric algorithms, GE, to optimize the results of the computer code will improve heat exchanger disign.

  6. Estimated radiactive and shock loading of fusion reactor armor

    SciTech Connect

    Swift, D C

    2008-11-25

    Inertial confinement fusion (ICF) is of interest as a source of neutrons for proliferation-resistant and high burn-up fission reactor designs. ICF is a transient process, each implosion leading to energy release over a short period, with a continuous series of ICF operations needed to drive the fission reactor. ICF yields energy in the form of MeV-range neutrons and ions, and thermal x-rays. These radiations, particularly the thermal x-rays, can deposit a pulse of energy in the wall of the ICF chamber, inducing loading by isochoric heating (i.e. at constant volume before the material can expand) or by ablation of material from the surface. The explosion of the hot ICF system, and the compression of any fill material in the chamber, may also result in direct mechanical loading by a blast wave (decaying shock) reaching the chamber wall. The chamber wall must be able to survive the repetitive loading events for long enough for the reactor to operate economically. It is thus necessary to understand the loading induced by ICF systems in possible chamber wall designs, and to predict the response and life time of the wall. Estimates are given for the loading induced in the wall armor of the fusion chamber caused by ablative thermal radiation from the fusion plasma and by the hydrodynamic shock. Taking a version of the LIFE design as an example, the ablation pressure was estimated to be {approx}0.6 GPa with an approximately exponential decay with time constant {approx}0.6 ns. Radiation hydrodynamics simulations suggested that ablation of the W armor should be negligible.

  7. Use of data fusion to optimize contaminant transport predictions

    SciTech Connect

    Eeckhout, E. van

    1997-10-01

    The original data fusion workstation, as envisioned by Coleman Research Corp., was constructed under funding from DOE (EM-50) in the early 1990s. The intent was to demonstrate the viability of fusion and analysis of data from various types of sensors for waste site characterization, but primarily geophysical. This overall concept changed over time and evolved more towards hydrogeological (groundwater) data fusion after some initial geophysical fusion work focused at Coleman. This initial geophysical fusion platform was tested at Hanford and Fernald, and the later hydrogeological fusion work has been demonstrated at Pantex, Savannah River, the US Army Letterkenny Depot, a DoD Massachusetts site and a DoD California site. The hydrogeologic data fusion package has been spun off to a company named Fusion and Control Technology, Inc. This package is called the Hydrological Fusion And Control Tool (Hydro-FACT) and is being sold as a product that links with the software package, MS-VMS (MODFLOW-SURFACT Visual Modeling System), sold by HydroGeoLogic, Inc. MODFLOW is a USGS development, and is in the public domain. Since the government paid for the data fusion development at Coleman, the government and their contractors have access to the data fusion technology in this hydrogeologic package for certain computer platforms, but would probably have to hire FACT (Fusion and Control Technology, Inc.,) and/or HydroGeoLogic for some level of software and services. Further discussion in this report will concentrate on the hydrogeologic fusion module that is being sold as Hydro-FACT, which can be linked with MS-VMS.

  8. Wavelet analysis of fusion plasma transients

    SciTech Connect

    Dose, V.; Venus, G.; Zohm, H.

    1997-02-01

    Analysis of transient signals in the diagnostic of fusion plasmas often requires the simultaneous consideration of their time and frequency information. The newly emerging technique of wavelet analysis contains both time and frequency domains. Therefore it can be a valuable tool for the analysis of transients. In this paper the basic method of wavelet analysis is described. As an example, wavelet analysis is applied to the well-known phenomena of mode locking and fishbone instability. The results quantify the current qualitative understanding of these events in terms of instantaneous frequencies and amplitudes and encourage applications of the method to other problems. {copyright} {ital 1997 American Institute of Physics.}

  9. Fusion Welding of AerMet 100 Alloy

    SciTech Connect

    ENGLEHART, DAVID A.; MICHAEL, JOSEPH R.; NOVOTNY, PAUL M.; ROBINO, CHARLES V.

    1999-08-01

    A database of mechanical properties for weldment fusion and heat-affected zones was established for AerMet{reg_sign}100 alloy, and a study of the welding metallurgy of the alloy was conducted. The properties database was developed for a matrix of weld processes (electron beam and gas-tungsten arc) welding parameters (heat inputs) and post-weld heat treatment (PWHT) conditions. In order to insure commercial utility and acceptance, the matrix was commensurate with commercial welding technology and practice. Second, the mechanical properties were correlated with fundamental understanding of microstructure and microstructural evolution in this alloy. Finally, assessments of optimal weld process/PWHT combinations for cotildent application of the alloy in probable service conditions were made. The database of weldment mechanical properties demonstrated that a wide range of properties can be obtained in welds in this alloy. In addition, it was demonstrated that acceptable welds, some with near base metal properties, could be produced from several different initial heat treatments. This capability provides a means for defining process parameters and PWHT's to achieve appropriate properties for different applications, and provides useful flexibility in design and manufacturing. The database also indicated that an important region in welds is the softened region which develops in the heat-affected zone (HAZ) and analysis within the welding metallurgy studies indicated that the development of this region is governed by a complex interaction of precipitate overaging and austenite formation. Models and experimental data were therefore developed to describe overaging and austenite formation during thermal cycling. These models and experimental data can be applied to essentially any thermal cycle, and provide a basis for predicting the evolution of microstructure and properties during thermal processing.

  10. Structural characterization of Mumps virus fusion protein core

    SciTech Connect

    Liu Yueyong; Xu Yanhui; Lou Zhiyong; Zhu Jieqing; Hu Xuebo; Gao, George F.; Qiu Bingsheng . E-mail: Qiubs@sun.im.ac.cn; Rao Zihe . E-mail: raozh@xtal.tsinghua.edu.cn; Tien, Po . E-mail: tienpo@sun.im.ac.cn

    2006-09-29

    The fusion proteins of enveloped viruses mediating the fusion between the viral and cellular membranes comprise two discontinuous heptad repeat (HR) domains located at the ectodomain of the enveloped glycoproteins. The crystal structure of the fusion protein core of Mumps virus (MuV) was determined at 2.2 A resolution. The complex is a six-helix bundle in which three HR1 peptides form a central highly hydrophobic coiled-coil and three HR2 peptides pack against the hydrophobic grooves on the surface of central coiled-coil in an oblique antiparallel manner. Fusion core of MuV, like those of simian virus 5 and human respiratory syncytium virus, forms typical 3-4-4-4-3 spacing. The similar charecterization in HR1 regions, as well as the existence of O-X-O motif in extended regions of HR2 helix, suggests a basic rule for the formation of the fusion core of viral fusion proteins.

  11. InFusion: Advancing Discovery of Fusion Genes and Chimeric Transcripts from Deep RNA-Sequencing Data

    PubMed Central

    Okonechnikov, Konstantin; Imai-Matsushima, Aki; Seitz, Alexander; Meyer, Thomas F.; Garcia-Alcalde, Fernando

    2016-01-01

    Analysis of fusion transcripts has become increasingly important due to their link with cancer development. Since high-throughput sequencing approaches survey fusion events exhaustively, several computational methods for the detection of gene fusions from RNA-seq data have been developed. This kind of analysis, however, is complicated by native trans-splicing events, the splicing-induced complexity of the transcriptome and biases and artefacts introduced in experiments and data analysis. There are a number of tools available for the detection of fusions from RNA-seq data; however, certain differences in specificity and sensitivity between commonly used approaches have been found. The ability to detect gene fusions of different types, including isoform fusions and fusions involving non-coding regions, has not been thoroughly studied yet. Here, we propose a novel computational toolkit called InFusion for fusion gene detection from RNA-seq data. InFusion introduces several unique features, such as discovery of fusions involving intergenic regions, and detection of anti-sense transcription in chimeric RNAs based on strand-specificity. Our approach demonstrates superior detection accuracy on simulated data and several public RNA-seq datasets. This improved performance was also evident when evaluating data from RNA deep-sequencing of two well-established prostate cancer cell lines. InFusion identified 26 novel fusion events that were validated in vitro, including alternatively spliced gene fusion isoforms and chimeric transcripts that include intergenic regions. The toolkit is freely available to download from http:/bitbucket.org/kokonech/infusion. PMID:27907167

  12. Summary of progress in inertial confinement fusion

    SciTech Connect

    Younger, S.M.

    1992-12-31

    Progress in inertial confinement fusion (ICF) has been very rapid over the past two years. Significant advances have been made in the production of smooth laser beams, the focusing of light ions beams, and the development of heavy ion accelerators. The availability of advanced target diagnostics on several major drivers has resulted in an extensive database of target performance over a wide range of conditions. Theoretical models of ICF targets are approaching the predictive level with two and even three dimensional calculations becoming routine. Within the next several years information should be available to allow confident extrapolation to ignition on the next generation driver.

  13. Summary of progress in inertial confinement fusion

    SciTech Connect

    Younger, S.M.

    1992-01-01

    Progress in inertial confinement fusion (ICF) has been very rapid over the past two years. Significant advances have been made in the production of smooth laser beams, the focusing of light ions beams, and the development of heavy ion accelerators. The availability of advanced target diagnostics on several major drivers has resulted in an extensive database of target performance over a wide range of conditions. Theoretical models of ICF targets are approaching the predictive level with two and even three dimensional calculations becoming routine. Within the next several years information should be available to allow confident extrapolation to ignition on the next generation driver.

  14. Theory of supercompression of vapor bubbles and nanoscale thermonuclear fusion

    NASA Astrophysics Data System (ADS)

    Nigmatulin, Robert I.; Akhatov, Iskander Sh.; Topolnikov, Andrey S.; Bolotnova, Raisa Kh.; Vakhitova, Nailya K.; Lahey, Richard T.; Taleyarkhan, Rusi P.

    2005-10-01

    This paper provides the theoretical basis for energetic vapor bubble implosions induced by a standing acoustic wave. Its primary goal is to describe, explain, and demonstrate the plausibility of the experimental observations by Taleyarkhan et al. [Science 295, 1868 (2002); Phys. Rev. E 69, 036109 (2004)] of thermonuclear fusion for imploding cavitation bubbles in chilled deuterated acetone. A detailed description and analysis of these data, including a resolution of the criticisms that have been raised, together with some preliminary HYDRO code simulations, has been given by Nigmatulin et al. [Vestnik ANRB (Ufa, Russia) 4, 3 (2002); J. Power Energy 218-A, 345 (2004)] and Lahey et al. [Adv. Heat Transfer (to be published)]. In this paper a hydrodynamic shock (i.e., HYDRO) code model of the spherically symmetric motion for a vapor bubble in an acoustically forced liquid is presented. This model describes cavitation bubble cluster growth during the expansion period, followed by a violent implosion during the compression period of the acoustic cycle. There are two stages of the bubble dynamics process. The first, low Mach number stage, comprises almost all the time of the acoustic cycle. During this stage, the radial velocities are much less than the sound speeds in the vapor and liquid, the vapor pressure is very close to uniform, and the liquid is practically incompressible. This process is characterized by the inertia of the liquid, heat conduction, and the evaporation or condensation of the vapor. The second, very short, high Mach number stage is when the radial velocities are the same order, or higher, than the sound speeds in the vapor and liquid. In this stage high temperatures, pressures, and densities of the vapor and liquid take place. The model presented herein has realistic equations of state for the compressible liquid and vapor phases, and accounts for nonequilibrium evaporation/condensation kinetics at the liquid/vapor interface. There are interacting

  15. Theory of supercompression of vapor bubbles and nanoscale thermonuclear fusion

    SciTech Connect

    Nigmatulin, Robert I.; Akhatov, Iskander Sh.; Topolnikov, Andrey S.; Bolotnova, Raisa Kh.; Vakhitova, Nailya K.; Lahey, Richard T. Jr.; Taleyarkhan, Rusi P.

    2005-10-01

    This paper provides the theoretical basis for energetic vapor bubble implosions induced by a standing acoustic wave. Its primary goal is to describe, explain, and demonstrate the plausibility of the experimental observations by Taleyarkhan et al. [Science 295, 1868 (2002); Phys. Rev. E 69, 036109 (2004)] of thermonuclear fusion for imploding cavitation bubbles in chilled deuterated acetone. A detailed description and analysis of these data, including a resolution of the criticisms that have been raised, together with some preliminary HYDRO code simulations, has been given by Nigmatulin et al. [Vestnik ANRB (Ufa, Russia) 4, 3 (2002); J. Power Energy 218-A, 345 (2004)] and Lahey et al. [Adv. Heat Transfer (to be published)]. In this paper a hydrodynamic shock (i.e., HYDRO) code model of the spherically symmetric motion for a vapor bubble in an acoustically forced liquid is presented. This model describes cavitation bubble cluster growth during the expansion period, followed by a violent implosion during the compression period of the acoustic cycle. There are two stages of the bubble dynamics process. The first, low Mach number stage, comprises almost all the time of the acoustic cycle. During this stage, the radial velocities are much less than the sound speeds in the vapor and liquid, the vapor pressure is very close to uniform, and the liquid is practically incompressible. This process is characterized by the inertia of the liquid, heat conduction, and the evaporation or condensation of the vapor. The second, very short, high Mach number stage is when the radial velocities are the same order, or higher, than the sound speeds in the vapor and liquid. In this stage high temperatures, pressures, and densities of the vapor and liquid take place. The model presented herein has realistic equations of state for the compressible liquid and vapor phases, and accounts for nonequilibrium evaporation/condensation kinetics at the liquid/vapor interface. There are interacting

  16. Mutual control of membrane fission and fusion proteins.

    PubMed

    Peters, Christopher; Baars, Tonie L; Bühler, Susanne; Mayer, Andreas

    2004-11-24

    Membrane fusion and fission are antagonistic reactions controlled by different proteins. Dynamins promote membrane fission by GTP-driven changes of conformation and polymerization state, while SNAREs fuse membranes by forming complexes between t- and v-SNAREs from apposed vesicles. Here, we describe a role of the dynamin-like GTPase Vps1p in fusion of yeast vacuoles. Vps1p forms polymers that couple several t-SNAREs together. At the onset of fusion, the SNARE-activating ATPase Sec18p/NSF and the t-SNARE depolymerize Vps1p and release it from the membrane. This activity is independent of the SNARE coactivator Sec17p/alpha-SNAP and of the v-SNARE. Vps1p release liberates the t-SNAREs for initiating fusion and at the same time disrupts fission activity. We propose that reciprocal control between fusion and fission components exists, which may prevent futile cycles of fission and fusion.

  17. Evolution of an Intelligent Information Fusion System

    NASA Technical Reports Server (NTRS)

    Campbell, William J.; Cromp, Robert F.

    1990-01-01

    Consideration is given to the hardware and software needed to manage the enormous amount and complexity of data that the next generation of space-borne sensors will provide. An anthology is presented illustrating the evolution of artificial intelligence, science data processing, and management from the 1960s to the near future. Problems and limitations of technologies, data structures, data standards, and conceptual thinking are addressed. The development of an end-to-end Intelligent Information Fusion System that embodies knowledge of the user's domain-specific goals is proposed.

  18. Performance of advanced missions using fusion propulsion

    NASA Technical Reports Server (NTRS)

    Friedlander, Alan; Mcadams, Jim; Schulze, Norm

    1989-01-01

    A quantitive evaluation of the premise that nuclear fusion propulsion offers benefits as compared to other propulsion technologies for carrying out a program of advanced exploration of the solar system and beyond is presented. Using a simplified analytical model of trajectory performance, numerical results of mass requirements versus trip time are given for robotic missions beyond the solar system that include flyby and rendezvous with the Oort cloud of comets and with the star system Alpha Centauri. Round trip missions within the solar system, including robotic sample returns from the outer planet moons and multiple asteroid targets, and manned Mars exploration are also described.

  19. Local adaptation and the evolution of chromosome fusions.

    PubMed

    Guerrero, Rafael F; Kirkpatrick, Mark

    2014-10-01

    We use forward and coalescent models of population genetics to study chromosome fusions that reduce the recombination between two locally adapted loci. Under a continent-island model, a fusion spreads and reaches a polymorphic equilibrium when it causes recombination between locally adapted alleles to be less than their selective advantage. In contrast, fusions in a two-deme model always spread; whether it reaches a polymorphic equilibrium or becomes fixed depends on the relative recombination rates of fused homozygotes and heterozygotes. Neutral divergence around fusion polymorphisms is markedly increased, showing peaks at the point of fusion and at the locally adapted loci. Local adaptation could explain the evolution of many of chromosome fusions, which are some of the most common chromosome rearrangements in nature.

  20. Data fusion for the detection of buried land mines

    SciTech Connect

    Clark, G.A.; Sengupta, S.K.; Schaich, P.C.; Sherwood, R.J.; Buhl, M.R.; Hernandez, J.E.; Kane, R.J.; Barth, M.J.; Fields, D.J.; Carter, M.R.

    1993-10-01

    The authors conducted experiments to demonstrate the enhanced delectability of buried land mines using sensor fusion techniques. Multiple sensors, including imagery, infrared imagery, and ground penetrating radar, have been used to acquire data on a number of buried mines and mine surrogates. The authors present this data along with a discussion of the application of sensor fusion techniques for this particular detection problem. The authors describe the data fusion architecture and discuss some relevant results of these classification methods.

  1. Effects of entrance channel on fusion probability in hot fusion reactions

    NASA Astrophysics Data System (ADS)

    Zhu, Long; Su, Jun; Huang, Ching-Yuan; Zhang, Feng-Shou

    2016-12-01

    Within the framework of the dinuclear system (DNS) model, the fusion reactions leading to the compound nuclei 274Hs* and 286Cn* are investigated. The fusion probability as a function of DNS excitation energy is studied. The calculated results are in good agreement with the available experimental data. The obtained results show that the fusion probabilities are obviously enhanced for the reactions located at high place in potential energy surface, although these reactions may have small values of mass asymmetry. It is found that the enhancement is due to the large potential energy of the initial DNS. Supported by Natural Science Foundation of Guangdong Province China (2016A030310208). National Natural Science Foundation of China (11605296, 11405278, 11505150, 11635003), Fundamental Research Funds for the Central Universities (15 lgpy 30) and China Postdoctoral Science Foundation (2015M582730)

  2. Fusion for Space Propulsion

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Schafer, Charles (Technical Monitor)

    2001-01-01

    There is little doubt that humans will attempt to explore and develop the solar system in this century. A large amount of energy will be required for accomplishing this. The need for fusion propulsion is discussed. For a propulsion system, there are three important thermodynamical attributes: (1) The absolute amount of energy available, (2) the propellant exhaust velocity, and (3) the jet power per unit mass of the propulsion system (specific power). For human exploration and development of the solar system, propellant exhaust velocity in excess of 100 km/s and specific power in excess of 10 kW/kg are required. Chemical combustion can produce exhaust velocity up to about 5 km/s. Nuclear fission processes typically result in producing energy in the form of heat that needs to be manipulated at temperatures limited by materials to about 2,800 K. Using the energy to heat a hydrogen propellant increases the exhaust velocity by only a factor of about two. Alternatively the energy can be converted into electricity which is then used to accelerate particles to high exhaust velocity. The necessary power conversion and conditioning equipment, however, increases the mass of the propulsion system for the same jet power by more than two orders of magnitude over chemical system, thus greatly limits the thrust-to-weight ratio attainable. The principal advantage of the fission process is that its development is relatively mature and is available right now. If fusion can be developed, fusion appears to have the best of all worlds in terms of propulsion - it can provide the absolute amount, the propellant exhaust velocity, and the high specific jet power. An intermediate step towards pure fusion propulsion is a bimodal system in which a fission reactor is used to provide some of the energy to drive a fusion propulsion unit. The technical issues related to fusion for space propulsion are discussed. The technical priorities for developing and applying fusion for propulsion are

  3. Measuring the Fusion Cross-Section of Light Nuclei with Low-Intensity Beams

    NASA Astrophysics Data System (ADS)

    Steinbach, Tracy; Brown, Kyle; Hudan, Sylvie; Desouza, Romualdo

    2014-03-01

    Reactions between neutron-rich light nuclei have been proposed as a heat source in the crust of an accreting neutron star that triggers an X-ray superburst. To explore the probability of such fusion events as well as better understand the fusion dynamics between neutron-rich nuclei, an experimental program to measure the dependence of the fusion cross-section on neutron number has been initiated. Key to these measurements is developing an approach to measure the total fusion cross-section for beams of low-intensity light nuclei (<105 ions/s) on light targets. Fusion residues resulting from the fusion of oxygen nuclei with 12C at energies near and below the Coulomb barrier are directly measured and distinguished from unreacted beam particles on the basis of their energy and time-of-flight (TOF). The TOF is measured between a microchannel plate (MCP) detector and a segmented Si detector. Two initial problems were charge trapping in the Si detector and slit scattering in the MCP detector. These problems have both been minimized by implementing a gridless MCP detector and a new Si design making the measurement feasible. Supported by the US DOE under Grant No. DEFG02-88ER-40404

  4. Fusion of competing features is not serial.

    PubMed

    Herzog, Michael H; Parish, Landi; Koch, Christof; Fahle, Manfred

    2003-08-01

    How features of an object are bound into a unique percept is one of the puzzling problems in the cognitive and neuro-sciences. In order to investigate the spatio-temporal mechanisms of feature binding, we serially present two verniers with opposite offset directions for very short durations. Only one vernier is perceived with its offset dominated by the vernier presented second. This dominance reverses if the two verniers are followed by masking gratings, i.e. the first presented vernier dominates performance. Therefore, feature fusion can neither be explained completely by spatially local mechanisms nor by the temporal order of appearance of elements.

  5. Elements of Successful and Safe Fusion Experiment Operations

    SciTech Connect

    K. Rule, L. Cadwallader, Y. Takase, T. Norimatsu, O. Kaneko, M. Sato, and R. Savercool

    2009-02-03

    A group of fusion safety professionals contribute to a Joint Working Group (JWG) that performs occupational safety walkthroughs of US and Japanese fusion experiments on a routine basis to enhance the safety of visiting researchers. The most recent walkthrough was completed in Japan in March 2008 by the US Safety Monitor team. This paper gives the general conclusions on fusion facility personnel safety that can be drawn from the series of walkthroughs.

  6. Spatial Regulation of Membrane Fusion Controlled by Modification of Phosphoinositides

    PubMed Central

    Dumas, Fabrice; Byrne, Richard D.; Vincent, Ben; Hobday, Tina M. C.; Poccia, Dominic L.; Larijani, Banafshé

    2010-01-01

    Membrane fusion plays a central role in many cell processes from vesicular transport to nuclear envelope reconstitution at mitosis but the mechanisms that underlie fusion of natural membranes are not well understood. Studies with synthetic membranes and theoretical considerations indicate that accumulation of lipids characterised by negative curvature such as diacylglycerol (DAG) facilitate fusion. However, the specific role of lipids in membrane fusion of natural membranes is not well established. Nuclear envelope (NE) assembly was used as a model for membrane fusion. A natural membrane population highly enriched in the enzyme and substrate needed to produce DAG has been isolated and is required for fusions leading to nuclear envelope formation, although it contributes only a small amount of the membrane eventually incorporated into the NE. It was postulated to initiate and regulate membrane fusion. Here we use a multidisciplinary approach including subcellular membrane purification, fluorescence spectroscopy and Förster resonance energy transfer (FRET)/two-photon fluorescence lifetime imaging microscopy (FLIM) to demonstrate that initiation of vesicle fusion arises from two unique sites where these vesicles bind to chromatin. Fusion is subsequently propagated to the endoplasmic reticulum-derived membranes that make up the bulk of the NE to ultimately enclose the chromatin. We show how initiation of multiple vesicle fusions can be controlled by localised production of DAG and propagated bidirectionally. Phospholipase C (PLCγ), GTP hydrolysis and (phosphatidylinsositol-(4,5)-bisphosphate (PtdIns(4,5)P2) are required for the latter process. We discuss the general implications of membrane fusion regulation and spatial control utilising such a mechanism. PMID:20808914

  7. Fusion reactions of Ni,6458+124Sn

    NASA Astrophysics Data System (ADS)

    Jiang, C. L.; Stefanini, A. M.; Esbensen, H.; Rehm, K. E.; Almaraz-Calderon, S.; Avila, M. L.; Back, B. B.; Bourgin, D.; Corradi, L.; Courtin, S.; Fioretto, E.; Galtarossa, F.; Goasduff, A.; Haas, F.; Mazzocco, M. M.; Montanari, D.; Montagnoli, G.; Mijatovic, T.; Sagaidak, R.; Santiago-Gonzalez, D.; Scarlassara, F.; Strano, E. E.; Szilner, S.

    2015-04-01

    Measurements of fusion excitation functions of 58Ni+124Sn and 64Ni+124Sn are extended towards lower energy to cross sections of 1 μ b and are compared to detailed coupled-channels calculations. The calculations clearly show the importance of including transfer reactions in a coupled-channels treatment for such heavy systems. This result is different from the conclusion made in a previous article which claimed that the influence of transfer on fusion is not important for fusion reactions of Ni +Sn . In the energy region studied in this experiment no indication of fusion hindrance has been observed, which is consistent with a systematic study of this behavior.

  8. Multivariate Chemical Image Fusion of Vibrational Spectroscopic Imaging Modalities.

    PubMed

    Gowen, Aoife A; Dorrepaal, Ronan M

    2016-07-02

    Chemical image fusion refers to the combination of chemical images from different modalities for improved characterisation of a sample. Challenges associated with existing approaches include: difficulties with imaging the same sample area or having identical pixels across microscopic modalities, lack of prior knowledge of sample composition and lack of knowledge regarding correlation between modalities for a given sample. In addition, the multivariate structure of chemical images is often overlooked when fusion is carried out. We address these challenges by proposing a framework for multivariate chemical image fusion of vibrational spectroscopic imaging modalities, demonstrating the approach for image registration, fusion and resolution enhancement of chemical images obtained with IR and Raman microscopy.

  9. Gasification of high ash, high ash fusion temperature bituminous coals

    DOEpatents

    Liu, Guohai; Vimalchand, Pannalal; Peng, WanWang

    2015-11-13

    This invention relates to gasification of high ash bituminous coals that have high ash fusion temperatures. The ash content can be in 15 to 45 weight percent range and ash fusion temperatures can be in 1150.degree. C. to 1500.degree. C. range as well as in excess of 1500.degree. C. In a preferred embodiment, such coals are dealt with a two stage gasification process--a relatively low temperature primary gasification step in a circulating fluidized bed transport gasifier followed by a high temperature partial oxidation step of residual char carbon and small quantities of tar. The system to process such coals further includes an internally circulating fluidized bed to effectively cool the high temperature syngas with the aid of an inert media and without the syngas contacting the heat transfer surfaces. A cyclone downstream of the syngas cooler, operating at relatively low temperatures, effectively reduces loading to a dust filtration unit. Nearly dust- and tar-free syngas for chemicals production or power generation and with over 90%, and preferably over about 98%, overall carbon conversion can be achieved with the preferred process, apparatus and methods outlined in this invention.

  10. Fundamental studies of fusion plasmas

    SciTech Connect

    Aamodt, R.E.; Catto, P.J.; D'Ippolito, D.A.; Myra, J.R.; Russell, D.A.

    1992-05-26

    The major portion of this program is devoted to critical ICH phenomena. The topics include edge physics, fast wave propagation, ICH induced high frequency instabilities, and a preliminary antenna design for Ignitor. This research was strongly coordinated with the world's experimental and design teams at JET, Culham, ORNL, and Ignitor. The results have been widely publicized at both general scientific meetings and topical workshops including the speciality workshop on ICRF design and physics sponsored by Lodestar in April 1992. The combination of theory, empirical modeling, and engineering design in this program makes this research particularly important for the design of future devices and for the understanding and performance projections of present tokamak devices. Additionally, the development of a diagnostic of runaway electrons on TEXT has proven particularly useful for the fundamental understanding of energetic electron confinement. This work has led to a better quantitative basis for quasilinear theory and the role of magnetic vs. electrostatic field fluctuations on electron transport. An APS invited talk was given on this subject and collaboration with PPPL personnel was also initiated. Ongoing research on these topics will continue for the remainder fo the contract period and the strong collaborations are expected to continue, enhancing both the relevance of the work and its immediate impact on areas needing critical understanding.

  11. Safety and environmental constraints on space applications of fusion energy

    NASA Technical Reports Server (NTRS)

    Roth, J. Reece

    1990-01-01

    Some of the constraints are examined on fusion reactions, plasma confinement systems, and fusion reactors that are intended for such space related missions as manned or unmanned operations in near earth orbit, interplanetary missions, or requirements of the SDI program. Of the many constraints on space power and propulsion systems, those arising from safety and environmental considerations are emphasized since these considerations place severe constraints on some fusion systems and have not been adequately treated in previous studies.

  12. Fusion Studies in Japan

    NASA Astrophysics Data System (ADS)

    Ogawa, Yuichi

    2016-05-01

    A new strategic energy plan decided by the Japanese Cabinet in 2014 strongly supports the steady promotion of nuclear fusion development activities, including the ITER project and the Broader Approach activities from the long-term viewpoint. Atomic Energy Commission (AEC) in Japan formulated the Third Phase Basic Program so as to promote an experimental fusion reactor project. In 2005 AEC has reviewed this Program, and discussed on selection and concentration among many projects of fusion reactor development. In addition to the promotion of ITER project, advanced tokamak research by JT-60SA, helical plasma experiment by LHD, FIREX project in laser fusion research and fusion engineering by IFMIF were highly prioritized. Although the basic concept is quite different between tokamak, helical and laser fusion researches, there exist a lot of common features such as plasma physics on 3-D magnetic geometry, high power heat load on plasma facing component and so on. Therefore, a synergetic scenario on fusion reactor development among various plasma confinement concepts would be important.

  13. Physical measurements of inertial-fusion targets

    SciTech Connect

    Weinstein, B.W.

    1981-09-24

    Measurement of inertial-fusion targets has stimulated the development of many new techniques and instruments. This paper reviews the basis for selected target measurement requirements and the development of optical interferometry, optical scattering, microradiography and scanning electron microscopy as applied to target measurement. We summarize the resolution and speed which have been achieved to date, and describe several systems in which these are traded off to fill specific measurement applications. We point out the extent to which present capabilities meet the requirements for target measurement and the key problems which remain to be solved.

  14. Applications of Fusion Energy Sciences Research - Scientific Discoveries and New Technologies Beyond Fusion

    SciTech Connect

    Wendt, Amy; Callis, Richard; Efthimion, Philip; Foster, John; Keane, Christopher; Onsager, Terry; O'Shea, Patrick

    2015-09-01

    Since the 1950s, scientists and engineers in the U.S. and around the world have worked hard to make an elusive goal to be achieved on Earth: harnessing the reaction that fuels the stars, namely fusion. Practical fusion would be a source of energy that is unlimited, safe, environmentally benign, available to all nations and not dependent on climate or the whims of the weather. Significant resources, most notably from the U.S. Department of Energy (DOE) Office of Fusion Energy Sciences (FES), have been devoted to pursuing that dream, and significant progress is being made in turning it into a reality. However, that is only part of the story. The process of creating a fusion-based energy supply on Earth has led to technological and scientific achievements of far-reaching impact that touch every aspect of our lives. Those largely unanticipated advances, spanning a wide variety of fields in science and technology, are the focus of this report. There are many synergies between research in plasma physics (the study of charged particles and fluids interacting with self-consistent electric and magnetic fields), high-energy physics, and condensed matter physics dating back many decades. For instance, the formulation of a mathematical theory of solitons, solitary waves which are seen in everything from plasmas to water waves to Bose-Einstein Condensates, has led to an equal span of applications, including the fields of optics, fluid mechanics and biophysics. Another example, the development of a precise criterion for transition to chaos in Hamiltonian systems, has offered insights into a range of phenomena including planetary orbits, two-person games and changes in the weather. Seven distinct areas of fusion energy sciences were identified and reviewed which have had a recent impact on fields of science, technology and engineering not directly associated with fusion energy: Basic plasma science; Low temperature plasmas; Space and astrophysical plasmas; High energy density

  15. Muon sticking factor in muon catalyzed fusion and the other aspect of this fusion process

    SciTech Connect

    Takahashi, H.

    1986-01-01

    The effect of resonance nuclear fusion reaction on the initial muon sticking factor is formulated. The analysis shows that it is very sensitive to the resonance parameter, and the factor calculated, using the molecular wave function obtained by the Diffusion Monte Carlo method, is 0.1 +- 0.01 for the presently evaluated resonance parameter. The analysis of the multistep excitation effect on the reactivation factor shows that the effect is not so large, and the analysis of muonic x-ray spectra of ..mu../sup 3/He from P..mu..d and d..mu..d fusions is in good agreement with the values measured by Bossy et al.

  16. Stalk model of membrane fusion: solution of energy crisis.

    PubMed Central

    Kozlovsky, Yonathan; Kozlov, Michael M

    2002-01-01

    Membrane fusion proceeds via formation of intermediate nonbilayer structures. The stalk model of fusion intermediate is commonly recognized to account for the major phenomenology of the fusion process. However, in its current form, the stalk model poses a challenge. On one hand, it is able to describe qualitatively the modulation of the fusion reaction by the lipid composition of the membranes. On the other, it predicts very large values of the stalk energy, so that the related energy barrier for fusion cannot be overcome by membranes within a biologically reasonable span of time. We suggest a new structure for the fusion stalk, which resolves the energy crisis of the model. Our approach is based on a combined deformation of the stalk membrane including bending of the membrane surface and tilt of the hydrocarbon chains of lipid molecules. We demonstrate that the energy of the fusion stalk is a few times smaller than those predicted previously and the stalks are feasible in real systems. We account quantitatively for the experimental results on dependence of the fusion reaction on the lipid composition of different membrane monolayers. We analyze the dependence of the stalk energy on the distance between the fusing membranes and provide the experimentally testable predictions for the structural features of the stalk intermediates. PMID:11806930

  17. Coupled edge-core model of fusion reactor

    NASA Astrophysics Data System (ADS)

    Zagórski, R.; Kulinski, S.; Scholz, M.

    1997-10-01

    A model has been developed which is capable to describe in a self consistent way the plasma dynamics in the centre and edge region of a fusion reactor. The core plasma is treated in the frame of the 0D model in which an empirical scaling law for the energy confinement time is included. The model accounts for energy losses due to Bremsstrahlung and line radiation as well as alpha particle heating. A 1D analytical model for plasma and impurity transport outside the last close magnetic surface (LCMS) is applied. The model accounts for the strong gradients of the plasma parameters along the magnetic field lines in the divertor. The sputtering phenomena at the plate and radiating cooling by injected impurities are treated self consistently in the model. The model has been used to investigate operating regimes of the ignition experiment. Analysis have been performed for different first wall materials (C, Ni, Mo, W) for ITER like tokamak.

  18. Economic aspects of heavy ion fusion

    SciTech Connect

    Herrmannsfeldt, W.B.

    1984-01-01

    The usual parameter space for examining scenarios for heavy ion fusion power plants has generally been based on large, slow cycling, reactor chambers which are only marginally different from chambers proposed for laser drivers. This paper will examine the economic implications of assuming that an inexpensive, low gain pellet is available and that a suitable high-repetition rate reactor has been devised. Interesting scenarios are found that generate economically feasible power from a system with a minimum net capacity of approx. 1 GWe compared to the larger approx. 4 GWe required in previous studies.

  19. Opportunistic replacement of fusion power system parts

    SciTech Connect

    Day, J.A.; George, L.L.

    1981-10-26

    This paper describes a maintenance problem in a fusion power plant. The problem is to specify which life limited parts should be replaced when there is an opportunity. The objective is to minimize the cost rate of replacement parts and of maintenance actions while satisfying a power plant availability constraint. The maintenance policy is to look ahead and replace all parts that will reach their life limits within a time called a screen. Longer screens yield greater system availabilities because more parts are replaced prior to their life limits.

  20. A review of recent fusion neutronics experiments

    SciTech Connect

    Maekawa, Hiroshi; Oyama, Yukio; Ikeda, Yujiro

    1994-12-31

    This paper reviews experimental activities in fusion neutronics experiments since the last International Conference on Nuclear Data. Many experiments have been carried out in Japan at FNS/JAERI, OKTAVIAN /Osaka University and KURRI/Kyoto University. Experiments on Be were performed at INEL/USA, KfK/FRG, SINPC/PRC, OKTAVIAN/Japan and several institutes in CIS, Czech Republic and Ukraine. A new series of shielding experiments have been started at FNS, ENEA/Frascati, TUD and Russian institutes for ITER/EDA R&D program.

  1. Accelerator and Fusion Research Division: Summary of activities, 1986

    SciTech Connect

    Not Available

    1987-04-15

    This report contains a summary of activities at the Lawrence Berkeley Laboratory's Accelerator and Fusion Research Division for the year 1986. Topics and facilities investigated in individual papers are: 1-2 GeV Synchrotron Radiation Source, the Center for X-Ray Optics, Accelerator Operations, High-Energy Physics Technology, Heavy-Ion Fusion Accelerator Research and Magnetic Fusion Energy. Six individual papers have been indexed separately. (LSP)

  2. The effect of proton halo on fusion reactions

    NASA Astrophysics Data System (ADS)

    Lay, J. A.; Kumar, Raj; Vitturi, A.

    2015-04-01

    In a recent brief report [Kumar et al., Phys. Rev. C 89, 027601 (2014)] we proposed a method to include the effect of a large break up in fusion reactions with neutron and proton halo nuclei. A stronger enhancement on the total fusion cross section was found for the proton case. However, neither complete nor incomplete fusion was studied and only one target was considered. Here, we revisit the problem in order to address the importance of complete and incomplete fusion. The sensitivity of the cross section to the target is also explored.

  3. Development of a Multifilament PIT V3Ga Conductor for Fusion Applications

    SciTech Connect

    Distin, J.S.; Ghosh, A.; Motowidlo, L.R.; Lee, P.J.; Larbalestier, D.C.; Lu, X.F.; Cheggour, N.; Stauffer, T.C.; Goodrich, L.F.

    2011-08-03

    Previous studies on V{sub 3}Ga assert its suitability for use in proposed fusion reactors. V{sub 3}Ga may outperform Nb{sub 3}Sn in a fusion reactor environment based on its relatively flat critical-current profile in the 15 T-20 T range, resilience to applied strain, and reduced risk of induced radioactivity. A multifilament powder-in-tube V{sub 3}Ga conductor was designed, fabricated and tested with a focus on evaluating critical current versus applied field and applied strain performance, wire drawing difficulties, heat-treatment optimization, and overall feasibility of the concept.

  4. Adaptive fusion of infrared and visible images in dynamic scene

    NASA Astrophysics Data System (ADS)

    Yang, Guang; Yin, Yafeng; Man, Hong; Desai, Sachi

    2011-11-01

    Multiple modalities sensor fusion has been widely employed in various surveillance and military applications. A variety of image fusion techniques including PCA, wavelet, curvelet and HSV has been proposed in recent years to improve human visual perception for object detection. One of the main challenges for visible and infrared image fusion is to automatically determine an optimal fusion strategy for different input scenes along with an acceptable computational cost. This paper, we propose a fast and adaptive feature selection based image fusion method to obtain high a contrast image from visible and infrared sensors for targets detection. At first, fuzzy c-means clustering is applied on the infrared image to highlight possible hotspot regions, which will be considered as potential targets' locations. After that, the region surrounding the target area is segmented as the background regions. Then image fusion is locally applied on the selected target and background regions by computing different linear combination of color components from registered visible and infrared images. After obtaining different fused images, histogram distributions are computed on these local fusion images as the fusion feature set. The variance ratio which is based on Linear Discriminative Analysis (LDA) measure is employed to sort the feature set and the most discriminative one is selected for the whole image fusion. As the feature selection is performed over time, the process will dynamically determine the most suitable feature for the image fusion in different scenes. Experiment is conducted on the OSU Color-Thermal database, and TNO Human Factor dataset. The fusion results indicate that our proposed method achieved a competitive performance compared with other fusion algorithms at a relatively low computational cost.

  5. Modeling and numerical analysis of a magneto-inertial fusion concept with the target created through FRC merging

    NASA Astrophysics Data System (ADS)

    Li, Chenguang; Yang, Xianjun

    2016-10-01

    The Magnetized Plasma Fusion Reactor concept is proposed as a magneto-inertial fusion approach based on the target plasma created through the collision merging of two oppositely translating field reversed configuration plasmas, which is then compressed by the imploding liner driven by the pulsed-power driver. The target creation process is described by a two-dimensional magnetohydrodynamics model, resulting in the typical target parameters. The implosion process and the fusion reaction are modeled by a simple zero-dimensional model, taking into account the alpha particle heating and the bremsstrahlung radiation loss. The compression on the target can be 2D cylindrical or 2.4D with the additive axial contraction taken into account. The dynamics of the liner compression and fusion burning are simulated and the optimum fusion gain and the associated target parameters are predicted. The scientific breakeven could be achieved at the optimized conditions.

  6. Office of Fusion Energy Sciences. A ten-year perspective (2015-2025)

    SciTech Connect

    2015-12-01

    The vision described here builds on the present U.S. activities in fusion plasma and materials science relevant to the energy goal and extends plasma science at the frontier of discovery. The plan is founded on recommendations made by the National Academies, a number of recent studies by the Fusion Energy Sciences Advisory Committee (FESAC), and the Administration’s views on the greatest opportunities for U.S. scientific leadership.This report highlights five areas of critical importance for the U.S. fusion energy sciences enterprise over the next decade: 1) Massively parallel computing with the goal of validated whole-fusion-device modeling will enable a transformation in predictive power, which is required to minimize risk in future fusion energy development steps; 2) Materials science as it relates to plasma and fusion sciences will provide the scientific foundations for greatly improved plasma confinement and heat exhaust; 3) Research in the prediction and control of transient events that can be deleterious to toroidal fusion plasma confinement will provide greater confidence in machine designs and operation with stable plasmas; 4) Continued stewardship of discovery in plasma science that is not expressly driven by the energy goal will address frontier science issues underpinning great mysteries of the visible universe and help attract and retain a new generation of plasma/fusion science leaders; 5) FES user facilities will be kept world-leading through robust operations support and regular upgrades. Finally, we will continue leveraging resources among agencies and institutions and strengthening our partnerships with international research facilities.

  7. Validation test of fusion grade superconductors

    NASA Astrophysics Data System (ADS)

    Prasad, U.; Pradhan, S.; Raj, P.; Varmora, P.; Panchal, A.; Bano, A.; Ghate, M.

    2017-02-01

    The need of high magnetic field for long pulse operation of Tokamaks and future fusion reactors is an essential requirement. The superconducting magnets operating at low temperature, high current and produce high magnetic field for long time can certainly full-fill this requirement. Three types of magnets namely central solenoid, toroidal filed and poloidal filed are used for initiation, confinement and equilibrium of plasma. The presently available basic conductors for these magnets are Nb3Sn, Nb3Al, NbTi and MgB2. The presently operating SST-1 Tokamak has superconducting magnets made up of NbTi as basic conductor. The design and prototype initiative for SST-2 magnets has also begun at IPR. The low temperature and high magnetic field characterization of in-house developed and commercial superconducting strands have also been initiated in the custom made standard test facility at IPR. Encouraging results on testing of Nb3Sn, NbTi and MgB2 have been found for suitability of these conductors for magnets and current leads. The basic test set up and test results of fusion grade conductors will be discussed in this presentation.

  8. Tissue fusion bursting pressure and the role of tissue water content

    NASA Astrophysics Data System (ADS)

    Cezo, James; Kramer, Eric; Taylor, Kenneth; Ferguson, Virginia; Rentschler, Mark

    2013-02-01

    Tissue fusion is a complex, poorly understood process which bonds collagenous tissues together using heat and pressure. The goal of this study is to elucidate the role of hydration in bond efficacy. Hydration of porcine splenic arteries (n=30) was varied by pre-fusion treatments: 24-48 hour immersion in isotonic, hypotonic, or hypertonic baths. Treated arteries were fused in several locations using Conmed's Altrus thermal fusion device and the bursting pressure was then measured for each fused segment. Artery sections were then weighed before and after lyophilization, to quantify water content. Histology (HE, EVG staining) enabled visualization of the bonding interface. Bursting pressure was significantly greater (p=4.17 E-ll) for the hypotonic group (607.6 +/- 83.2mmHg), while no significant difference existed between the isotonic (332.6 +/- 44.7mmHg) and hypertonic (348.7 +/- 44.0mmHg) treatment groups. Total water content varied (p=8.80 E-24) from low water content in the hypertonic samples (72.5% weight +/- 0.9), to high water content in the hypotonic samples (83.1% weight +/- 1.9), while the isotonic samples contained 78.8% weight +/- 1.1. Strength differences between the treated vessels imply that bound water driven from the tissue during fusion may reveal available collagen crosslinking sites to facilitate bond formation during the fusion process. Thus when the tissue contains greater bound water volumes, more crosslinking sites may become available during fusion, leading to a stronger bond. This study provides an important step towards understanding the chemistry underlying tissue fusion and the mechanics of tissue fusion as a function of bound water within the tissue.

  9. Fusion of radar and satellite target measurements

    NASA Astrophysics Data System (ADS)

    Moy, Gabriel; Blaty, Donald; Farber, Morton; Nealy, Carlton

    2011-06-01

    A potentially high payoff for the ballistic missile defense system (BMDS) is the ability to fuse the information gathered by various sensor systems. In particular, it may be valuable in the future to fuse measurements made using ground based radars with passive measurements obtained from satellite-based EO/IR sensors. This task can be challenging in a multitarget environment in view of the widely differing resolution between active ground-based radar and an observation made by a sensor at long range from a satellite platform. Additionally, each sensor system could have a residual pointing bias which has not been calibrated out. The problem is further compounded by the possibility that an EO/IR sensor may not see exactly the same set of targets as a microwave radar. In order to better understand the problems involved in performing the fusion of metric information from EO/IR satellite measurements with active microwave radar measurements, we have undertaken a study of this data fusion issue and of the associated data processing techniques. To carry out this analysis, we have made use of high fidelity simulations to model the radar observations from a missile target and the observations of the same simulated target, as gathered by a constellation of satellites. In the paper, we discuss the improvements seen in our tests when fusing the state vectors, along with the improvements in sensor bias estimation. The limitations in performance due to the differing phenomenology between IR and microwave radar are discussed as well.

  10. Radioscapholunate Fusions

    PubMed Central

    McGuire, Duncan Thomas; Bain, Gregory Ian

    2012-01-01

    Radiocarpal fusions are performed for a variety of indications, most commonly for debilitating painful arthritis. The goal of a wrist fusion is to fuse the painful, diseased joints and to preserve motion through the healthy joints. Depending on the extent of the disease process, radiocarpal fusions may take the form of radiolunate, radioscapholunate, or total wrist fusions. Surgical techniques and instrumentation have advanced over the last few decades, and consequently the functional outcomes have improved and complications decreased. Techniques for partial carpal fusions have improved and now include distal scaphoid and triquetrum excision, which improves range of motion and fusion rates. In this article we discuss the various surgical techniques and fixation methods available and review the corresponding evidence in the literature. The authors' preferred surgical technique of radioscapholunate fusion with distal scaphoid and triquetrum excision is outlined. New implants and new concepts are also discussed. PMID:24179717

  11. Improvement on the thermal stability and activity of plant cytosolic ascorbate peroxidase 1 by tailing hyper-acidic fusion partners.

    PubMed

    Zhang, Mengru; Gong, Ming; Yang, Yumei; Li, Xujuan; Wang, Haibo; Zou, Zhurong

    2015-04-01

    Cytosolic ascorbate peroxidase 1 (APX1) plays a crucial role in regulating the level of plant cellular reactive oxygen species and its thermolability is proposed to cause plant heat-susceptibility. Herein, several hyper-acidic fusion partners, such as the C-terminal peptide tails, were evaluated for their effects on the thermal stability and activity of APX1 from Jatropha curcas and Arabidopsis. The hyper-acidic fusion partners efficiently improved the thermostability and prevented thermal inactivation of APX1 in both plant species with an elevated heat tolerance of at least 2 °C. These hyper-acidified thermostable APX1 fusion variants are of considerable biotechnological potential and can provide a new route to enhance the heat tolerance of plant species especially of inherent thermo-sensitivity.

  12. Degenerative spondylolisthesis: contemporary review of the role of interbody fusion.

    PubMed

    Baker, Joseph F; Errico, Thomas J; Kim, Yong; Razi, Afshin

    2017-02-01

    Degenerative spondylolisthesis is a common presentation, yet the best surgical treatment continues to be a matter of debate. Interbody fusion is one of a number of options, but its exact role remains ill defined. The aim of this study was to provide a contemporary review of the literature to help determine the role, if any, of interbody fusion in the surgical treatment of degenerative spondylolisthesis. A systematic review of the literature since 2005 was performed. Details on study size, patient age, surgical treatments, levels of slip, patient reported outcome measures, radiographic outcomes, complications and selected utility measures were recorded. Studies that compared a cohort treated with interbody fusion and at least one other surgical intervention for comparison were included for review. Only studies examining the effect in degenerative spondylolisthesis were included. Two authors independently reviewed the manuscripts and extracted key data. Thirteen studies were included in the final analysis. A total of 565 underwent interbody fusion and 761 underwent other procedures including decompression alone, interspinous stabilisation and posterolateral fusion with or without instrumentation. Most studies were graded Level III evidence. Heterogeneous reporting of outcomes prevented formal statistical analysis. However, in general, studies reviewed concluded no significant clinical or radiographic difference in outcome between interbody fusion and other treatments. Two small studies suggested interbody fusion is a better option in cases of definite instability. Interbody fusion only provided outcomes as good as instrumented posterolateral fusion. However, most studies were Level III, and hence, we remain limited in defining the exact role of interbody fusion-cases with clear instability appear to be most appropriate. Future work should use agreed-upon common outcome measures and definitions.

  13. Effective Thermal Conductivity of Lithium Ceramic Pebble Beds for Fusion Blankets: A Review

    SciTech Connect

    Abou-Sena, A.; Ying, A.; Abdou, M.

    2005-05-15

    The use of lithium ceramic pebble beds has been considered in many blanket designs for the fusion reactors. Lithium ceramics have received a significant interest as tritium breeders for the fusion blankets during the last three decades. The thermal performance of the lithium ceramic pebble beds plays a key role for the fusion blankets. In order to study the heat transfer in the blanket, the effective thermal conductivity of the lithium ceramics pebble beds has to be well measured and characterized. The data of effective thermal conductivity of lithium ceramic pebble beds is important for the blanket design. Several studies have been dedicated to investigate the effective conductivity of the lithium ceramics pebble beds. The objective of this work is to review and compare the available data, presented by various studies, of effective conductivity of lithium ceramic pebble beds in order to address the current status of these data.

  14. Cold fusion, Alchemist's dream

    SciTech Connect

    Clayton, E.D.

    1989-09-01

    In this report the following topics relating to cold fusion are discussed: muon catalysed cold fusion; piezonuclear fusion; sundry explanations pertaining to cold fusion; cosmic ray muon catalysed cold fusion; vibrational mechanisms in excited states of D{sub 2} molecules; barrier penetration probabilities within the hydrogenated metal lattice/piezonuclear fusion; branching ratios of D{sub 2} fusion at low energies; fusion of deuterons into {sup 4}He; secondary D+T fusion within the hydrogenated metal lattice; {sup 3}He to {sup 4}He ratio within the metal lattice; shock induced fusion; and anomalously high isotopic ratios of {sup 3}He/{sup 4}He.

  15. The cytoplasmic domain of the gamete membrane fusion protein HAP2 targets the protein to the fusion site in Chlamydomonas and regulates the fusion reaction

    PubMed Central

    Liu, Yanjie; Pei, Jimin; Grishin, Nick; Snell, William J.

    2015-01-01

    Cell-cell fusion between gametes is a defining step during development of eukaryotes, yet we know little about the cellular and molecular mechanisms of the gamete membrane fusion reaction. HAP2 is the sole gamete-specific protein in any system that is broadly conserved and shown by gene disruption to be essential for gamete fusion. The wide evolutionary distribution of HAP2 (also known as GCS1) indicates it was present in the last eukaryotic common ancestor and, therefore, dissecting its molecular properties should provide new insights into fundamental features of fertilization. HAP2 acts at a step after membrane adhesion, presumably directly in the merger of the lipid bilayers. Here, we use the unicellular alga Chlamydomonas to characterize contributions of key regions of HAP2 to protein location and function. We report that mutation of three strongly conserved residues in the ectodomain has no effect on targeting or fusion, although short deletions that include those residues block surface expression and fusion. Furthermore, HAP2 lacking a 237-residue segment of the cytoplasmic region is expressed at the cell surface, but fails to localize at the apical membrane patch specialized for fusion and fails to rescue fusion. Finally, we provide evidence that the ancient HAP2 contained a juxta-membrane, multi-cysteine motif in its cytoplasmic region, and that mutation of a cysteine dyad in this motif preserves protein localization, but substantially impairs HAP2 fusion activity. Thus, the ectodomain of HAP2 is essential for its surface expression, and the cytoplasmic region targets HAP2 to the site of fusion and regulates the fusion reaction. PMID:25655701

  16. The cytoplasmic domain of the gamete membrane fusion protein HAP2 targets the protein to the fusion site in Chlamydomonas and regulates the fusion reaction.

    PubMed

    Liu, Yanjie; Pei, Jimin; Grishin, Nick; Snell, William J

    2015-03-01

    Cell-cell fusion between gametes is a defining step during development of eukaryotes, yet we know little about the cellular and molecular mechanisms of the gamete membrane fusion reaction. HAP2 is the sole gamete-specific protein in any system that is broadly conserved and shown by gene disruption to be essential for gamete fusion. The wide evolutionary distribution of HAP2 (also known as GCS1) indicates it was present in the last eukaryotic common ancestor and, therefore, dissecting its molecular properties should provide new insights into fundamental features of fertilization. HAP2 acts at a step after membrane adhesion, presumably directly in the merger of the lipid bilayers. Here, we use the unicellular alga Chlamydomonas to characterize contributions of key regions of HAP2 to protein location and function. We report that mutation of three strongly conserved residues in the ectodomain has no effect on targeting or fusion, although short deletions that include those residues block surface expression and fusion. Furthermore, HAP2 lacking a 237-residue segment of the cytoplasmic region is expressed at the cell surface, but fails to localize at the apical membrane patch specialized for fusion and fails to rescue fusion. Finally, we provide evidence that the ancient HAP2 contained a juxta-membrane, multi-cysteine motif in its cytoplasmic region, and that mutation of a cysteine dyad in this motif preserves protein localization, but substantially impairs HAP2 fusion activity. Thus, the ectodomain of HAP2 is essential for its surface expression, and the cytoplasmic region targets HAP2 to the site of fusion and regulates the fusion reaction.

  17. Single residue deletions along the length of the influenza HA fusion peptide lead to inhibition of membrane fusion function

    SciTech Connect

    Langley, William A.; Thoennes, Sudha; Bradley, Konrad C.; Galloway, Summer E.; Talekar, Ganesh R.; Cummings, Sandra F.; Vareckova, Eva; Russell, Rupert J.; Steinhauer, David A.

    2009-11-25

    A panel of eight single amino acid deletion mutants was generated within the first 24 residues of the fusion peptide domain of the of the hemagglutinin (HA) of A/Aichi/2/68 influenza A virus (H3N2 subtype). The mutant HAs were analyzed for folding, cell surface transport, cleavage activation, capacity to undergo acid-induced conformational changes, and membrane fusion activity. We found that the mutant DELTAF24, at the C-terminal end of the fusion peptide, was expressed in a non-native conformation, whereas all other deletion mutants were transported to the cell surface and could be cleaved into HA1 and HA2 to activate membrane fusion potential. Furthermore, upon acidification these cleaved HAs were able to undergo the characteristic structural rearrangements that are required for fusion. Despite this, all mutants were inhibited for fusion activity based on two separate assays. The results indicate that the mutant fusion peptide domains associate with target membranes in a non-functional fashion, and suggest that structural features along the length of the fusion peptide are likely to be relevant for optimal membrane fusion activity.

  18. Swelling of nuclei embedded in neutron-gas and consequences for fusion

    NASA Astrophysics Data System (ADS)

    Umar, A. S.; Oberacker, V. E.; Horowitz, C. J.; Reinhard, P.-G.; Maruhn, J. A.

    2015-08-01

    Fusion of very neutron rich nuclei may be important to determine the composition and heating of the crust of accreting neutron stars. We present an exploratory study of the effect of the neutron-gas environment on the structure of nuclei and the consequences for pycnonuclear fusion cross sections in the neutron drip region. We studied the formation and properties of oxygen and calcium isotopes embedded in varying neutron-gas densities. We observe that the formed isotope is the drip-line nucleus for the given effective interaction. Increasing the neutron-gas density leads to the swelling of the nuclear density. We have used these densities to study the effect of this swelling on the fusion cross sections using the São Paulo potential. At high neutron-gas densities the cross section is substantially increased but at lower densities the modification is minimal.

  19. Complexity versus availability for fusion: The potential advantages of inertial fusion energy

    SciTech Connect

    Perkins, L.J.,

    1996-09-05

    Probably the single largest advantage of the inertial route to fusion energy (IFE) is the perception that its power plant embodiments could achieve acceptable capacity factors. This is a result of its relative simplicity, the decoupling of the driver and reactor chamber, and the potential to employ thick liquid walls. We examine these issues in terms of the complexity, reliability, maintainability and, therefore, availability of both magnetic and inertial fusion power plants and compare these factors with corresponding scheduled and unscheduled outage data from present day fission experience. We stress that, given the simple nature of a fission core, the vast majority of unplanned outages in fission plants are due to failures outside the reactor vessel itself Given we must be prepared for similar outages in the analogous plant external to a fusion power core, this puts severe demands on the reliability required of the fusion core itself. We indicate that such requirements can probably be met for IFE plants. We recommend that this advantage be promoted by performing a quantitative reliability and availability study for a representative IFE power plant and suggest that databases are probably adequate for this task.

  20. Variable control of neutron albedo in toroidal fusion devices

    DOEpatents

    Jassby, D.L.; Micklich, B.J.

    1983-06-01

    This invention pertains to methods of controlling in the steady state, neutron albedo in toroidal fusion devices, and in particular, to methods of controlling the flux and energy distribution of collided neutrons which are incident on an outboard wall of a toroidal fusion device.

  1. Integrated simulation of magnetic-field-assist fast ignition laser fusion

    NASA Astrophysics Data System (ADS)

    Johzaki, T.; Nagatomo, H.; Sunahara, A.; Sentoku, Y.; Sakagami, H.; Hata, M.; Taguchi, T.; Mima, K.; Kai, Y.; Ajimi, D.; Isoda, T.; Endo, T.; Yogo, A.; Arikawa, Y.; Fujioka, S.; Shiraga, H.; Azechi, H.

    2017-01-01

    To enhance the core heating efficiency in fast ignition laser fusion, the concept of relativistic electron beam guiding by external magnetic fields was evaluated by integrated simulations for FIREX class targets. For the cone-attached shell target case, the core heating performance deteriorates by applying magnetic fields since the core is considerably deformed and most of the fast electrons are reflected due to the magnetic mirror formed through the implosion. On the other hand, in the case of a cone-attached solid ball target, the implosion is more stable under the kilo-tesla-class magnetic field. In addition, feasible magnetic field configuration is formed through the implosion. As a result, the core heating efficiency doubles by magnetic guiding. The dependence of core heating properties on the heating pulse shot timing was also investigated for the solid ball target.

  2. Estimating heat capacity and heat content of rocks

    USGS Publications Warehouse

    Robertson, Eugene C.; Hemingway, Bruch S.

    1995-01-01

    Our measured heat-capacity values for rocks and other measurements of heat capacity or heat content of rocks found in the literature have been compared with estimated rock heat capacities calculated from the summation of heat capacities of both minerals and oxide components. The validity of calculating the heat content or heat capacity of rocks to better than about ± 3% from its mineral or chemical composition is well demonstrated by the data presented here.

  3. Preliminary analysis of patent trends for magnetic fusion technology

    SciTech Connect

    Levine, L.O.; Ashton, W.B.; Campbell, R.S.

    1984-02-01

    This study presents a preliminary analysis of development trends in magnetic fusion technology based on data from US patents. The research is limited to identification and description of general patent activity and ownership characteristics for 373 patents. The results suggest that more detailed studies of fusion patents could provide useful R and D planning information.

  4. Enhancement of data analysis through multisensor data fusion technology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This paper focuses on application of multisensor data fusion for high quality data analysis and processing in measurement and instrumentation. A practical, general data fusion scheme is established on the basis of feature extraction and merging of data from multiple sensors. This scheme integrates...

  5. Botulinum toxin in the management of acquired motor fusion deficiency

    PubMed Central

    Murthy, Ramesh; Kesarwani, Siddharth

    2009-01-01

    Acquired disruption of motor fusion is a rare condition characterized by intractable diplopia. Management of these patients is extremely difficult. Prisms in any combination or even surgery may not help relieve their symptoms. We describe a longstanding case of acquired motor fusion disruption which was managed successfully with botulinum toxin injection. PMID:19861751

  6. Base of the Measles Virus Fusion Trimer Head Receives the Signal That Triggers Membrane Fusion*

    PubMed Central

    Apte-Sengupta, Swapna; Negi, Surendra; Leonard, Vincent H. J.; Oezguen, Numan; Navaratnarajah, Chanakha K.; Braun, Werner; Cattaneo, Roberto

    2012-01-01

    The measles virus (MV) fusion (F) protein trimer executes membrane fusion after receiving a signal elicited by receptor binding to the hemagglutinin (H) tetramer. Where and how this signal is received is understood neither for MV nor for other paramyxoviruses. Because only the prefusion structure of the parainfluenza virus 5 (PIV5) F-trimer is available, to study signal receipt by the MV F-trimer, we generated and energy-refined a homology model. We used two approaches to predict surface residues of the model interacting with other proteins. Both approaches measured interface propensity values for patches of residues. The second approach identified, in addition, individual residues based on the conservation of physical chemical properties among F-proteins. Altogether, about 50 candidate interactive residues were identified. Through iterative cycles of mutagenesis and functional analysis, we characterized six residues that are required specifically for signal transmission; their mutation interferes with fusion, although still allowing efficient F-protein processing and cell surface transport. One residue is located adjacent to the fusion peptide, four line a cavity in the base of the F-trimer head, while the sixth residue is located near this cavity. Hydrophobic interactions in the cavity sustain the fusion process and contacts with H. The cavity is flanked by two different subunits of the F-trimer. Tetrameric H-stalks may be lodged in apposed cavities of two F-trimers. Because these insights are based on a PIV5 homology model, the signal receipt mechanism may be conserved among paramyxoviruses. PMID:22859308

  7. Indirect drive targets for fusion power

    DOEpatents

    Amendt, Peter A.; Miles, Robin R.

    2016-10-11

    A hohlraum for an inertial confinement fusion power plant is disclosed. The hohlraum includes a generally cylindrical exterior surface, and an interior rugby ball-shaped surface. Windows over laser entrance holes at each end of the hohlraum enclose inert gas. Infrared reflectors on opposite sides of the central point reflect fusion chamber heat away from the capsule. P2 shields disposed on the infrared reflectors help assure an enhanced and more uniform x-ray bath for the fusion fuel capsule.

  8. Gyrokinetic Simulation of Energetic Particles Turbulence and Transport in Fusion Plasmas

    NASA Astrophysics Data System (ADS)

    Zhang, Wenlu; Lin, Zhihong; Holod, Ihor; Xiao, Yong; Bierwage, Andreas; Spong, Donald; Chu, Ming

    2009-05-01

    The confinement of the energetic particles (EP) is a critical issue in the International Thermonuclear Experimental Reactor (ITER), since that ignition relies on the self-heating by the fusion products. Shear Alfven wave excitations by EP in toroidal systems, for example Toroidal Alfven Eigenmode (TAE) and Energetic Particle Mode (EPM) have been investigated as primary candidate for fluctuation-induced transport of EP in fusion plasma. In this work, TAE excitations by energetic particles are investigated in large scale first-principle simulations of fusion plasmas using the global gyrokinetic toroidal code (GTC) [Lin, Science 1998]. Comprehensive linear benchmarking results are reported between GTC, GYRO, fluid code TAEFL, and Magnetohydrodynamic-gyrokinetic hybrid code HMGC.

  9. Nanodisc-cell fusion: control of fusion pore nucleation and lifetimes by SNARE protein transmembrane domains

    PubMed Central

    Wu, Zhenyong; Auclair, Sarah M.; Bello, Oscar; Vennekate, Wensi; Dudzinski, Natasha R.; Krishnakumar, Shyam S.; Karatekin, Erdem

    2016-01-01

    The initial, nanometer-sized connection between the plasma membrane and a hormone- or neurotransmitter-filled vesicle –the fusion pore– can flicker open and closed repeatedly before dilating or resealing irreversibly. Pore dynamics determine release and vesicle recycling kinetics, but pore properties are poorly known because biochemically defined single-pore assays are lacking. We isolated single flickering pores connecting v-SNARE-reconstituted nanodiscs to cells ectopically expressing cognate, “flipped” t-SNAREs. Conductance through single, voltage-clamped fusion pores directly reported sub-millisecond pore dynamics. Pore currents fluctuated, transiently returned to baseline multiple times, and disappeared ~6 s after initial opening, as if the fusion pore fluctuated in size, flickered, and resealed. We found that interactions between v- and t-SNARE transmembrane domains (TMDs) promote, but are not essential for pore nucleation. Surprisingly, TMD modifications designed to disrupt v- and t-SNARE TMD zippering prolonged pore lifetimes dramatically. We propose that the post-fusion geometry of the proteins contribute to pore stability. PMID:27264104

  10. General principles of magnetic fusion confinement

    SciTech Connect

    Hogan, J.T.

    1980-01-01

    A few of the areas are described in which there is close interaction between atomic/molecular (A and M) and magnetic fusion physics. The comparisons between predictions of neoclassical transport theory and experiment depend on knowledge of ionization and recombination rate coefficients. Modeling of divertor/scrapeoff plasmas requires better low energy charge exchange cross sections for H + A/sup n+/ collisions. The range of validity of neutral beam trapping cross sections must be broadened, both to encompass the energies typical of present injection experiments and to deal with the problem of prompt trapping of highly excited beam atoms at high energy. Plasma fueling models present certain anomalies that could be resolved by calculation and measurement of low energy (<1 keV) charge exchange cross sections.

  11. Auto-fusion and the shaping of neurons and tubes.

    PubMed

    Soulavie, Fabien; Sundaram, Meera V

    2016-12-01

    Cells adopt specific shapes that are necessary for specific functions. For example, some neurons extend elaborate arborized dendrites that can contact multiple targets. Epithelial and endothelial cells can form tiny seamless unicellular tubes with an intracellular lumen. Recent advances showed that cells can auto-fuse to acquire those specific shapes. During auto-fusion, a cell merges two parts of its own plasma membrane. In contrast to cell-cell fusion or macropinocytic fission, which result in the merging or formation of two separate membrane bound compartments, auto-fusion preserves one compartment, but changes its shape. The discovery of auto-fusion in C. elegans was enabled by identification of specific protein fusogens, EFF-1 and AFF-1, that mediate cell-cell fusion. Phenotypic characterization of eff-1 and aff-1 mutants revealed that fusogen-mediated fusion of two parts of the same cell can be used to sculpt dendritic arbors, reconnect two parts of an axon after injury, or form a hollow unicellular tube. Similar auto-fusion events recently were detected in vertebrate cells, suggesting that auto-fusion could be a widely used mechanism for shaping neurons and tubes.

  12. Enhancement of Data Analysis Through Multisensor Data Fusion Technology

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Multi-sensor data fusion is an emerging technology that fuses data from multiple sensors in order to make a more accurate estimation of the environment through measurement and detection. Applications of multi-sensor data fusion cross a wide spectrum in military and civilian areas. With the rapid e...

  13. Training The Next Generation Of Fusion Scientists And Engineers: Summer High School Fusion Science Workshop

    NASA Astrophysics Data System (ADS)

    Punjabi, Alkesh

    2005-10-01

    The goal of the education and outreach activities of the Hampton University Center for Fusion Research and Training (HU CFRT) is to create a high school-to-Ph.D. pipeline in plasma physics, fusion science, and related sciences for underrepresented minorities and female students. The HU CFRT Summer High School Fusion Research Workshop is an integral component of this pipeline. This workshop has been extraordinarily successful. The workshop participants are chosen from a national pool of young and talented minority and female high school students through the NASA SHARP program. These students come to HU from all over US and its possessions for eight weeks during the summer. Over the last ten years, these workshops have provided one-on-one high quality research experiences in fusion science to the best and the brightest minority and female high school students in the nation. Our high school students have presented over 25 contributed papers at APS/DPP annual meetings, twice reached semi-finalist positions in Siemens-Westinghouse competitions, won awards and prizes, admissions and scholarships to prestigious universities, and won high praises from the fusion research community and other educators and researchers. We wish to emphasize that we have been able to achieve these results with limited human and fiscal resources and a meager infrastructure. Here we will present the details of how this workshop has evolved over the years, the approaches, the activities, and the structure that we have used to train, motivate, and provide valuable research experiences to the next generation of our national leaders in science. We thank the U.S. DOE OFES for supporting these efforts. We also thank Dr. Allen Boozer and Dr. Thomas Simonen for their invaluable help in the workshop and in all our efforts.

  14. LIFE: The Case for Early Commercialization of Fusion Energy

    SciTech Connect

    Anklam, T; Simon, A J; Powers, S; Meier, W R

    2010-11-30

    This paper presents the case for early commercialization of laser inertial fusion energy (LIFE). Results taken from systems modeling of the US electrical generating enterprise quantify the benefits of fusion energy in terms of carbon emission, nuclear waste and plutonium production avoidance. Sensitivity of benefits-gained to timing of market-entry is presented. These results show the importance of achieving market entry in the 2030 time frame. Economic modeling results show that fusion energy can be competitive with other low-carbon energy sources. The paper concludes with a description of the LIFE commercialization path. It proposes constructing a demonstration facility capable of continuous fusion operations within 10 to 15 years. This facility will qualify the processes and materials needed for a commercial fusion power plant.

  15. Major achievements and challenges of fusion research

    NASA Astrophysics Data System (ADS)

    Tendler, Michael

    2015-09-01

    The ITER project is truly at the frontier of knowledge, a collective effort to explore the tantalizing future of free, clean and inexhaustible energy offered by nuclear fusion. Where the Large Hadron Collider at CERN pushes the boundaries of physics to find the origins of matter, the ITER Project seeks to give humans an endless stream of power which could have potentially game-changing consequences for the entire planet. Seminal contributions to the general physics knowledge accomplished by the plasma physics research for the benefit of the ITER project will be brought to light. The legacy of Professor H Alfvén within the framework of the ITER project will be described.

  16. Mechanical-engineering aspects of mirror-fusion technology

    SciTech Connect

    Fisher, D.K.; Doggett, J.N.

    1982-07-15

    The mirror approach to magnetic fusion has evolved from the original simple mirror cell to today's mainline effort: the tandem-mirror machine with thermal barriers. Physics and engineering research is being conducted throughout the world, with major efforts in Japan, the USSR, and the US. At least one facility under construction (MFTF-B) will approach equivalent energy breakeven in physics performance. Significant mechanical engineering development is needed, however, before a demonstration reactor can be constructed. The principal areas crucial to mirror reactor development include large high-field superconducting magnets, high-speed continuous vacuum-pumping systems, long-pulse high-power neutral-beam and rf-plasma heating systems, and efficient high-voltage high-power direct converters. Other areas common to all fusion systems include tritium handling technology, first-wall materials development, and fusion blanket design.

  17. 76 FR 4645 - Fusion Energy Sciences Advisory Committee; Notice of Open Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-26

    ... Fusion Nuclear Sciences Pathways Assessment Activities Public Comments Public Participation: The meeting... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Fusion... Science. SUMMARY: This notice announces a meeting of the Fusion Energy Sciences Advisory Committee....

  18. Numerical Studies of Impurities in Fusion Plasmas

    DOE R&D Accomplishments Database

    Hulse, R. A.

    1982-09-01

    The coupled partial differential equations used to describe the behavior of impurity ions in magnetically confined controlled fusion plasmas require numerical solution for cases of practical interest. Computer codes developed for impurity modeling at the Princeton Plasma Physics Laboratory are used as examples of the types of codes employed for this purpose. These codes solve for the impurity ionization state densities and associated radiation rates using atomic physics appropriate for these low-density, high-temperature plasmas. The simpler codes solve local equations in zero spatial dimensions while more complex cases require codes which explicitly include transport of the impurity ions simultaneously with the atomic processes of ionization and recombination. Typical applications are discussed and computational results are presented for selected cases of interest.

  19. Overview of Indian activities on fusion reactor materials

    NASA Astrophysics Data System (ADS)

    Banerjee, Srikumar

    2014-12-01

    This paper on overview of Indian activities on fusion reactor materials describes in brief the efforts India has made to develop materials for the first wall of a tokamak, its blanket and superconducting magnet coils. Through a systematic and scientific approach, India has developed and commercially produced reduced activation ferritic/martensitic (RAFM) steel that is comparable to Eurofer 97. Powder of low activation ferritic/martensitic oxide dispersion strengthened steel with characteristics desired for its application in the first wall of a tokamak has been produced on the laboratory scale. V-4Cr-4Ti alloy was also prepared in the laboratory, and kinetics of hydrogen absorption in this was investigated. Cu-1 wt%Cr-0.1 wt%Zr - an alloy meant for use as heat transfer elements for hypervapotrons and heat sink for the first wall - was developed and characterized in detail for its aging behavior. The role of addition of a small quantity of Zr in its improved fatigue performance was delineated, and its diffusion bonding with both W and stainless steel was achieved using Ni as an interlayer. The alloy was produced in large quantities and used for manufacturing both the heat transfer elements and components for the International Thermonuclear Experimental Reactor (ITER). India has proposed to install and test a lead-lithium cooled ceramic breeder test blanket module (LLCB-TBM) at ITER. To meet this objective, efforts have been made to produce and characterize Li2TiO3 pebbles, and also improve the thermal conductivity of packed beds of these pebbles. Liquid metal loops have been set up and corrosion behavior of RAFM steel in flowing Pb-Li eutectic has been studied in the presence as well as absence of magnetic fields. To prevent permeation of tritium and reduce the magneto-hydro-dynamic drag, processes have been developed for coating alumina on RAFM steel. Apart from these activities, different approaches being attempted to make the U-shaped first wall of the TBM box

  20. Physical and mechanical characteristics and chemical compatibility of aluminum nitride insulator coatings for fusion reactor applications

    SciTech Connect

    Natesan, K.; Rink, D.L.

    1996-04-01

    The blanket system is one of the most important components in a fusion reactor because it has a major impact on both the economics and safety of fusion energy. The primary functions of the blanket in a deuterium/tritium-fueled fusion reactor are to convert the fusion energy into sensible heat and to breed tritium for the fuel cycle. The Blanket Comparison and Selection Study, conducted earlier, described the overall comparative performance of various concepts, including liquid metal, molten salt, water, and helium. Based on the requirements for an electrically insulating coating on the first-wall structural material to minimize the MHD pressure drop during the flow of liquid metal in a magnetic field, AlN was selected as a candidate coating material for the Li self-cooled blanket concept. This report discusses the results from an ongoing study of physical and mechanical characteristics and chemical compatibility of AlN electrical insulator coatings in a liquid Li environment. Details are presented on the AlN coating fabrication methods, and experimental data are reported for microstructures, chemistry of coatings, pretreatment of substrate, heat treatment of coatings, hardness data for coatings, coating/lithium interactions, and electrical resistance before and after exposure to lithium. Thermodynamic calculations are presented to establish regions of stability for AlN coatings in an Li environment as a function of O concentration and temperature, which can aid in-situ development of AlN coatings in Li.

  1. Current Status of Lumbar Interbody Fusion for Degenerative Spondylolisthesis

    PubMed Central

    TAKAHASHI, Toshiyuki; HANAKITA, Junya; OHTAKE, Yasufumi; FUNAKOSHI, Yusuke; OICHI, Yuki; KAWAOKA, Taigo; WATANABE, Mizuki

    2016-01-01

    Instrumented lumbar fusion can provide immediate stability and assist in satisfactory arthrodesis in patients who have pain or instability of the lumbar spine. Lumbar adjunctive fusion with decompression is often a good procedure for surgical management of degenerative spondylolisthesis (DS). Among various lumbar fusion techniques, lumbar interbody fusion (LIF) has an advantage in that it maintains favorable lumbar alignment and provides successful fusion with the added effect of indirect decompression. This technique has been widely used and represents an advancement in spinal instrumentation, although the rationale and optimal type of LIF for DS remains controversial. We evaluated the current status and role of LIF in DS treatment, mainly as a means to augment instrumentation. We addressed the basic concept of LIF, its indications, and various types including minimally invasive techniques. It also has acceptable biomechanical features, and offers reconstruction with ideal lumbar alignment. Postsurgical adverse events related to each LIF technique are also addressed. PMID:27169496

  2. Methods of detection using a cellulose binding domain fusion product

    DOEpatents

    Shoseyov, Oded; Shpiegl, Itai; Goldstein, Marc A.; Doi, Roy H.

    1999-01-01

    A cellulose binding domain (CBD) having a high affinity for crystalline cellulose and chitin is disclosed, along with methods for the molecular cloning and recombinant production thereof. Fusion products comprising the CBD and a second protein are likewise described. A wide range of applications are contemplated for both the CBD and the fusion products, including drug delivery, affinity separations, and diagnostic techniques.

  3. Measurements of fusion product emission profiles in tokamaks

    SciTech Connect

    Strachan, J.D.; Heidbrink, W.W.; Hendel, H.W.; Lovberg, J.; Murphy, T.J.; Nieschmidt, E.B.; Tait, G.D.; Zweben, S.J.

    1986-11-01

    The techniques and results of fusion product emission profile measurements are reviewed. While neutron source strength profile measurements have been attempted by several methods, neutron scattering is a limitation to the results. Profile measurements using charged fusion products have recently provided an alternative since collimation is much easier for the charged particles.

  4. Methods of detection using a cellulose binding domain fusion product

    DOEpatents

    Shoseyov, O.; Shpiegl, I.; Goldstein, M.A.; Doi, R.H.

    1999-01-05

    A cellulose binding domain (CBD) having a high affinity for crystalline cellulose and chitin is disclosed, along with methods for the molecular cloning and recombinant production. Fusion products comprising the CBD and a second protein are likewise described. A wide range of applications are contemplated for both the CBD and the fusion products, including drug delivery, affinity separations, and diagnostic techniques. 34 figs.

  5. Mitochondrial fusion and inheritance of the mitochondrial genome.

    PubMed

    Takano, Hiroyoshi; Onoue, Kenta; Kawano, Shigeyuki

    2010-03-01

    Although maternal or uniparental inheritance of mitochondrial genomes is a general rule, biparental inheritance is sometimes observed in protists and fungi,including yeasts. In yeast, recombination occurs between the mitochondrial genomes inherited from both parents.Mitochondrial fusion observed in yeast zygotes is thought to set up a space for DNA recombination. In the last decade,a universal mitochondrial fusion mechanism has been uncovered, using yeast as a model. On the other hand, an alternative mitochondrial fusion mechanism has been identified in the true slime mold Physarum polycephalum.A specific mitochondrial plasmid, mF, has been detected as the genetic material that causes mitochondrial fusion in P. polycephalum. Without mF, fusion of the mitochondria is not observed throughout the life cycle, suggesting that Physarum has no constitutive mitochondrial fusion mechanism.Conversely, mitochondria fuse in zygotes and during sporulation with mF. The complete mF sequence suggests that one gene, ORF640, encodes a fusogen for Physarum mitochondria. Although in general, mitochondria are inherited uniparentally, biparental inheritance occurs with specific sexual crossing in P. polycephalum.An analysis of the transmission of mitochondrial genomes has shown that recombinations between two parental mitochondrial genomes require mitochondrial fusion,mediated by mF. Physarum is a unique organism for studying mitochondrial fusion.

  6. A survey of multi-sensor data fusion systems

    NASA Astrophysics Data System (ADS)

    Linn, R. J.; Hall, D. L.; Llinas, J.

    1991-08-01

    Multisensor data fusion integrates data from multiple sensors (and types of sensors) to perform inferences which are more accurate and specific than those from processing single-sensor data. Levels of inference range from target detection and identification to higher level situation assessment and threat assessment. This paper provides a survey of more than 50 data fusion systems and summarizes their application, development environment, system status and key techniques. The techniques are mapped to a taxonomy previously developed by Hall and Linn (1990); these include positional fusion techniques, such as association and estimation, and identity fusion methods, including statistical methods, nonparametric methods, and cognitive techniques (e.g. templating, knowledge-based systems, and fuzzy reasoning). An assessment of the state of fusion system development is provided.

  7. Decommissioning of the Tokamak Fusion Test Reactor

    SciTech Connect

    E. Perry; J. Chrzanowski; C. Gentile; R. Parsells; K. Rule; R. Strykowsky; M. Viola

    2003-10-28

    The Tokamak Fusion Test Reactor (TFTR) at the Princeton Plasma Physics Laboratory was operated from 1982 until 1997. The last several years included operations with mixtures of deuterium and tritium. In September 2002, the three year Decontamination and Decommissioning (D&D) Project for TFTR was successfully completed. The need to deal with tritium contamination as well as activated materials led to the adaptation of many techniques from the maintenance work during TFTR operations to the D&D effort. In addition, techniques from the decommissioning of fission reactors were adapted to the D&D of TFTR and several new technologies, most notably the development of a diamond wire cutting process for complex metal structures, were developed. These techniques, along with a project management system that closely linked the field crews to the engineering staff who developed the techniques and procedures via a Work Control Center, resulted in a project that was completed safely, on time, and well below budget.

  8. Organotypic three-dimensional culture model of mesenchymal and epithelial cells to examine tissue fusion events.

    EPA Science Inventory

    Tissue fusion during early mammalian development requires coordination of multiple cell types, the extracellular matrix, and complex signaling pathways. Fusion events during processes including heart development, neural tube closure, and palatal fusion are dependent on signaling ...

  9. Production of specific antibodies against protein A fusion proteins.

    PubMed Central

    Löwenadler, B; Nilsson, B; Abrahmsén, L; Moks, T; Ljungqvist, L; Holmgren, E; Paleus, S; Josephson, S; Philipson, L; Uhlén, M

    1986-01-01

    The gene for Staphylococcal protein A was fused to the coding sequence of bacterial beta-galactosidase, alkaline phosphatase and human insulin-like growth factor I (IGF-I). The fusion proteins, expressed in bacteria, were purified by affinity chromatography on IgG-Sepharose and antibodies were raised in rabbits. All three fusion proteins elicited specific antibodies against both the inserted protein sequences and the protein A moiety. In the case of IGF-I, the protein A moiety in the fusion protein may act as an adjuvant since native IGF-I alone is a poor immunogen. The results suggest that the protein A fusion system can be used for efficient antibody production against peptides or proteins expressed from cloned or synthetic genes. To facilitate such gene fusions a set of optimized vectors have been constructed. Images Fig. 2. Fig. 3. Fig. 4. Fig. 6. PMID:3096719

  10. Negative specific heat of a magnetically self-confined plasma torus

    PubMed Central

    Kiessling, Michael K.-H.; Neukirch, Thomas

    2003-01-01

    It is shown that the thermodynamic maximum-entropy principle predicts negative specific heat for a stationary, magnetically self-confined current-carrying plasma torus. Implications for the magnetic self-confinement of fusion plasma are considered. PMID:12576553

  11. Laboratory simulation of heat exchange for liquids with Pr > 1: Heat transfer

    NASA Astrophysics Data System (ADS)

    Belyaev, I. A.; Zakharova, O. D.; Krasnoshchekova, T. E.; Sviridov, V. G.; Sukomel, L. A.

    2016-02-01

    Liquid metals are promising heat transfer agents in new-generation nuclear power plants, such as fast-neutron reactors and hybrid tokamaks—fusion neutron sources (FNSs). We have been investigating hydrodynamics and heat exchange of liquid metals for many years, trying to reproduce the conditions close to those in fast reactors and fusion neutron sources. In the latter case, the liquid metal flow takes place in a strong magnetic field and strong thermal loads resulting in development of thermogravitational convection in the flow. In this case, quite dangerous regimes of magnetohydrodynamic (MHD) heat exchange not known earlier may occur that, in combination with other long-known regimes, for example, the growth of hydraulic drag in a strong magnetic field, make the possibility of creating a reliable FNS cooling system with a liquid metal heat carrier problematic. There exists a reasonable alternative to liquid metals in FNS, molten salts, namely, the melt of lithium and beryllium fluorides (Flibe) and the melt of fluorides of alkali metals (Flinak). Molten salts, however, are poorly studied media, and their application requires detailed scientific substantiation. We analyze the modern state of the art of studies in this field. Our contribution is to answer the following question: whether above-mentioned extremely dangerous regimes of MHD heat exchange detected in liquid metals can exist in molten salts. Experiments and numerical simulation were performed in order to answer this question. The experimental test facility represents a water circuit, since water (or water with additions for increasing its electrical conduction) is a convenient medium for laboratory simulation of salt heat exchange in FNS conditions. Local heat transfer coefficients along the heated tube, three-dimensional (along the length and in the cross section, including the viscous sublayer) fields of averaged temperature and temperature pulsations are studied. The probe method for measurements in

  12. Heat pipes and use of heat pipes in furnace exhaust

    DOEpatents

    Polcyn, Adam D.

    2010-12-28

    An array of a plurality of heat pipe are mounted in spaced relationship to one another with the hot end of the heat pipes in a heated environment, e.g. the exhaust flue of a furnace, and the cold end outside the furnace. Heat conversion equipment is connected to the cold end of the heat pipes.

  13. Membrane fusion triggers rapid degradation of two gamete-specific, fusion-essential proteins in a membrane block to polygamy in Chlamydomonas.

    PubMed

    Liu, Yanjie; Misamore, Michael J; Snell, William J

    2010-05-01

    The plasma membranes of gametes are specialized for fusion, yet, once fusion occurs, in many organisms the new zygote becomes incapable of further membrane fusion reactions. The molecular mechanisms that underlie this loss of fusion capacity (block to polygamy) remain unknown. During fertilization in the green alga Chlamydomonas, the plus gamete-specific membrane protein FUS1 is required for adhesion between the apically localized sites on the plasma membranes of plus and minus gametes that are specialized for fusion, and the minus-specific membrane protein HAP2 is essential for completion of the membrane fusion reaction. HAP2 (GCS1) family members are also required for fertilization in Arabidopsis, and for the membrane fusion reaction in the malaria organism Plasmodium berghei. Here, we tested whether Chlamydomonas gamete fusion triggers alterations in FUS1 and HAP2 and renders the plasma membranes of the cells incapable of subsequent fusion. We find that, even though the fusogenic sites support multi-cell adhesions, triploid zygotes are rare, indicating a fusion-triggered block to the membrane fusion reaction. Consistent with the extinction of fusogenic capacity, both FUS1 and HAP2 are degraded upon fusion. The rapid, fusion-triggered cleavage of HAP2 in zygotes is distinct from degradation occurring during constitutive turnover in gametes. Thus, gamete fusion triggers specific degradation of fusion-essential proteins and renders the zygote incapable of fusion. Our results provide the first molecular explanation for a membrane block to polygamy in any organism.

  14. Membrane fusion triggers rapid degradation of two gamete-specific, fusion-essential proteins in a membrane block to polygamy in Chlamydomonas

    PubMed Central

    Liu, Yanjie; Misamore, Michael J.; Snell, William J.

    2010-01-01

    The plasma membranes of gametes are specialized for fusion, yet, once fusion occurs, in many organisms the new zygote becomes incapable of further membrane fusion reactions. The molecular mechanisms that underlie this loss of fusion capacity (block to polygamy) remain unknown. During fertilization in the green alga Chlamydomonas, the plus gamete-specific membrane protein FUS1 is required for adhesion between the apically localized sites on the plasma membranes of plus and minus gametes that are specialized for fusion, and the minus-specific membrane protein HAP2 is essential for completion of the membrane fusion reaction. HAP2 (GCS1) family members are also required for fertilization in Arabidopsis, and for the membrane fusion reaction in the malaria organism Plasmodium berghei. Here, we tested whether Chlamydomonas gamete fusion triggers alterations in FUS1 and HAP2 and renders the plasma membranes of the cells incapable of subsequent fusion. We find that, even though the fusogenic sites support multi-cell adhesions, triploid zygotes are rare, indicating a fusion-triggered block to the membrane fusion reaction. Consistent with the extinction of fusogenic capacity, both FUS1 and HAP2 are degraded upon fusion. The rapid, fusion-triggered cleavage of HAP2 in zygotes is distinct from degradation occurring during constitutive turnover in gametes. Thus, gamete fusion triggers specific degradation of fusion-essential proteins and renders the zygote incapable of fusion. Our results provide the first molecular explanation for a membrane block to polygamy in any organism. PMID:20335357

  15. Photothermal heating of nanoribbons

    NASA Astrophysics Data System (ADS)

    Smith, Bennett E.; Zhou, Xuezhe; Davis, E. James; Pauzauskie, Peter J.

    2017-01-01

    Nanoscale optical materials are of great interest for building future optoelectronic devices for information processing and sensing applications. Although heat transfer ultimately limits the maximum power at which nanoscale devices may operate, gaining a quantitative experimental measurement of photothermal heating within single nanostructures remains a challenge. Here, we measure the nonlinear optical absorption coefficient of optically trapped cadmium-sulfide nanoribbons at the level of single nanostructures through observations of their Brownian dynamics during single-beam laser trapping experiments. A general solution to the heat transfer partial differential equation is derived for nanostructures having rectilinear morphology including nanocubes and nanoribbons. Numerical electromagnetic calculations using the discrete-dipole approximation enable the simulation of the photothermal heating source function and the extraction of nonlinear optical absorption coefficients from experimental observations of single nanoribbon dynamics.

  16. Physics of laser fusion. Volume II. Diagnostics of experiments on laser fusion targets at LLNL

    SciTech Connect

    Ahlstrom, H.G.

    1982-01-01

    These notes present the experimental basis and status for laser fusion as developed at LLNL. There are two other volumes in this series: Vol. I, by C.E. Max, presents the theoretical laser-plasma interaction physics; Vol. III, by J.F. Holzrichter et al., presents the theory and design of high-power pulsed lasers. A fourth volume will present the theoretical implosion physics. The notes consist of six sections. The first, an introductory section, provides some of the history of inertial fusion and a simple explanation of the concepts involved. The second section presents an extensive discussion of diagnostic instrumentation used in the LLNL Laser Fusion Program. The third section is a presentation of laser facilities and capabilities at LLNL. The purpose here is to define capability, not to derive how it was obtained. The fourth and fifth sections present the experimental data on laser-plasma interaction and implosion physics. The last chapter is a short projection of the future.

  17. Reinvestigation of the charge density distribution in arc discharge fusion system

    SciTech Connect

    Sheng, Lin Horng; Yee, Lee Kim; Nan, Phua Yeong; Thung, Yong Yun; Khok, Yong Thian; Rahman, Faidz Abd

    2015-04-24

    A continual arc discharge system has been setup and the light intensity of arc discharge has been profiled. The mathematical model of local energy density distribution in arc discharge fusion has been simulated which is in good qualitative agreement with light intensity profile of arc discharge in the experiments. Eventually, the local energy density distribution of arc discharge system is able to be precisely manipulated to act as heat source in the fabrication of fused fiber devices.

  18. Evaluation of autologous platelet concentrate for intertransverse process lumbar fusion.

    PubMed

    Sethi, Paul M; Miranda, Jose J; Kadiyala, Sudha; Patel, Tushar Ch; Panjabi, Manohar; Troiano, Nancy; Friedlaender, Gary E

    2008-04-01

    Data on the role of platelet concentrate (PC) in spinal fusion are limited. Using the New Zealand white rabbit model, we compared fusion rates at L5-L6 using 2 different volumes (1.5 cm(3), 3.0 cm(3)) of iliac crest autograft with and without PC (4 groups total, 10 animals in each). PC was collected from donor rabbits and adjusted to a concentration of 1 x 10(6) platelets/mL. Bone growth and fusion were evaluated using biomechanical, radiographic, and histologic testing. At 1.5 cm(3), autograft alone had a 29% fusion rate, compared with autograft plus PC, which had a 57% fusion rate (P = .06). At 3.0 cm(3), the fusion rate approached 90% in both groups. Radiologic fusion had a 70% correlation with biomechanical test results. Huo/Friedlaender scores were 4.3 (SD, 2.9) for 1.5-cm(3) autograft alone; 5.0 (SD, 3.5) for 1.5-cm(3) autograft plus PC; 4.7 (SD, 2.5) for 3.0-cm(3) autograft alone; and 7.7 (SD, 0.6) for 3.0-cm(3) autograft plus PC. For 1.5-cm(3) autograft, a trend toward improvement in biomechanically defined fusion was found when PC was added, which suggests that, when the amount of bone graft is limited, PC may function as a graft extender in posterolateral fusion. At higher volumes of bone graft, no appreciable difference was noted between groups. Although radiography revealed fusion masses, the technique was not useful in identifying pseudarthrosis. On histologic analysis, adding PC seemed to result in more mature bone at both volumes, with the most mature bone in the group with 3.0-cm(3) autograft plus PC.

  19. Application of Magnetized Target Fusion to High-Energy Space Propulsion

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. F.; Schmidt, G. R.; Kirkpatrick, R. C.; Rodgers, Stephen L. (Technical Monitor)

    2001-01-01

    Most fusion propulsion concepts that have been investigated in the past employ some form of inertial or magnetic confinement. Although the prospective performance of these concepts is excellent, the fusion processes on which these concepts are based still require considerable development before they can be seriously considered for actual applications. Furthermore, these processes are encumbered by the need for sophisticated plasma and power handling systems that are generally quite inefficient and have historically resulted in large, massive spacecraft designs. Here we present a comparatively new approach, Magnetized Target Fusion (MTF), which offers a nearer-term avenue for realizing the tremendous performance benefits of fusion propulsion'. The key advantage of MTF is its less demanding requirements for driver energy and power processing. Additional features include: 1) very low system masses and volumes, 2) high gain and relatively low waste heat, 3) substantial utilization of energy from product neutrons, 4) efficient, low peak-power drivers based on existing pulsed power technology, and 5) very high Isp, specific power and thrust. MTF overcomes many of the problems associated with traditional fusion techniques, thus making it particularly attractive for space applications. Isp greater than 50,000 seconds and specific powers greater than 50 kilowatts/kilogram appear feasible using relatively near-term pulse power and plasma gun technology.

  20. Summary of the IEA workshop/working group meeting on ferritic/martensitic steels for fusion

    SciTech Connect

    Klueh, R.L.

    1997-04-01

    An International Energy Agency (IEA) Working Group on Ferritic/Martensitic Steels for Fusion Applications, consisting of researchers from Japan, the European Union, the United States, and Switzerland, met at the headquarters of the Joint European Torus (JET), Culham, United Kingdom, 24-25 October 1996. At the meeting preliminary data generated on the large heats of steel purchased for the IEA program and on other heats of steels were presented and discussed. The second purpose of the meeting was to continue planning and coordinating the collaborative test program in progress on reduced-activation ferritic/martensitic steels. The next meeting will be held in conjunction with the International Conference on Fusion Reactor Materials (ICFRM-8) in Sendai, Japan, 23-31 October 1997.

  1. Evaluation of a fusion-driven thruster for interplanetary and earth-to-orbit flight

    NASA Astrophysics Data System (ADS)

    Froning, H. D.; Watrus, John J.; Frese, Michael H.; Gerwin, Richard A.

    2000-01-01

    Investigations performed under a NASA Small Business Independent Research (SBIR) Phase I Award have shown that hydrogen propellant heating from fusion energy on the order of a few 1014 W/kg, corresponding to power absorption rates of a few GW, can produce on the order of 100 kN of thrust with a 0.5 kg/s propellant mass flow rate. .

  2. Magnetic-compression/magnetized-target fusion (MAGO/MTF): A marriage of inertial and magnetic confinement

    SciTech Connect

    Lindemuth, I.R.; Ekdahl, C.A.; Kirkpatrick, R.C.

    1996-12-31

    Intermediate between magnetic confinement (MFE) and inertial confinement (ICF) in time and density scales is an area of research now known in the US as magnetized target fusion (MTF) and in Russian as MAGO (MAGnitnoye Obzhatiye--magnetic compression). MAGO/MTF uses a magnetic field and preheated, wall-confined plasma fusion fuel within an implodable fusion target. The magnetic field suppresses thermal conduction losses in the fuel during the target implosion and hydrodynamic compression heating process. In contrast to direct, hydrodynamic compression of initially ambient-temperature fuel (i.e., ICF), MAGO/MTF involves two steps: (a) formation of a warm (e.g., 100 eV or higher), magnetized (e.g., 100 kG) plasma within a fusion target prior to implosion; (b) subsequent quasi-adiabatic compression by an imploding pusher, of which a magnetically driven imploding liner is one example. In this paper, the authors present ongoing activities and potential future activities in this relatively unexplored area of controlled thermonuclear fusion.

  3. Confinement and heating of a deuterium-tritium plasma

    SciTech Connect

    Hawryluk, R. J.; Adler, H.; Alling, P.; Synakowski, E.

    1994-03-01

    The Tokamak Fusion Test Reactor (TFTR) has performed initial high-power experiments with the plasma fueled by deuterium and tritium to nominally equal densities. Compared to pure deuterium plasmas, the energy stored in the electron and ions increased by ~20%. These increases indicate improvements in confinement associated with the use of tritium and possibly heating of electrons by α-particles.

  4. Formation of Vesicles Within the Fusion Crust of Eucritic Meteorites

    NASA Astrophysics Data System (ADS)

    Nicolau-Kuklińska, A.; Łosiak, A. I.

    2016-08-01

    Studying the development of fusion crusts will allow for the determination of the extent to which re-processing during atmospheric passage is changing the initial material of both meteorites and micrometeorites.

  5. Fusion breeder

    SciTech Connect

    Moir, R.W.

    1982-04-20

    The fusion breeder is a fusion reactor designed with special blankets to maximize the transmutation by 14 MeV neutrons of uranium-238 to plutonium or thorium to uranium-233 for use as a fuel for fission reactors. Breeding fissile fuels has not been a goal of the US fusion energy program. This paper suggests it is time for a policy change to make the fusion breeder a goal of the US fusion program and the US nuclear energy program. The purpose of this paper is to suggest this policy change be made and tell why it should be made, and to outline specific research and development goals so that the fusion breeder will be developed in time to meet fissile fuel needs.

  6. Fusion breeder

    SciTech Connect

    Moir, R.W.

    1982-02-22

    The fusion breeder is a fusion reactor designed with special blankets to maximize the transmutation by 14 MeV neutrons of uranium-238 to plutonium or thorium to uranium-233 for use as a fuel for fission reactors. Breeding fissile fuels has not been a goal of the US fusion energy program. This paper suggests it is time for a policy change to make the fusion breeder a goal of the US fusion program and the US nuclear energy program. The purpose of this paper is to suggest this policy change be made and tell why it should be made, and to outline specific research and development goals so that the fusion breeder will be developed in time to meet fissile fuel needs.

  7. Effect of structural forbiddenness in fusion of heavy nuclei

    NASA Astrophysics Data System (ADS)

    Adamian, G. G.; Antonenko, N. V.; Tchuvil'Sky, Yu. M.

    1999-04-01

    With a microscopic approach based on the formalism of irreducible representations of the SU(3) group the influence of structural forbiddenness on the fusion of heavy nuclei and the dinuclear system phenomenon are investigated for different symmetric and asymmetric reactions used in the synthesis of heavy and superheavy nuclei. The energy thresholds for complete fusion in relative distance and mass asymmetry degrees of freedom are estimated.

  8. Examination of the energy dependence of the fusion process

    NASA Astrophysics Data System (ADS)

    Torabi, F.; Ghodsi, O. N.; Pahlavani, M. R.

    2017-03-01

    In this study, the role of bombarding energy in analyzing the interaction potentials and describing the densities of interacting nuclei during fusion is investigated. For this purpose, the fusion cross sections of the 40Ca+48Ca , 16O+92Zr , and 40Ca+90Zr systems are calculated by the use of potentials derived from the semiclassical Skyrme energy density functional and the coupled-channel formalism. The comparisons drawn between the theoretical fusion data and the experimental ones demonstrate the energy-dependence behavior of the potentials employed in the calculations. Considering this dependence, we also show the variations of the density parameters of the colliding nuclei with the bombarding energy. The obtained results indicate that with increasing energy, the fusion barrier heights increase, while the diffuseness parameters of the densities decrease.

  9. Influence of incomplete fusion on complete fusion: Observation of a large incomplete fusion fraction at E {approx_equal}5-7 MeV/nucleon

    SciTech Connect

    Singh, Pushpendra P.; Singh, B. P.; Sharma, Manoj Kumar; Unnati,; Singh, Devendra P.; Prasad, R.; Kumar, Rakesh; Golda, K. S.

    2008-01-15

    Experiments have been carried out to explore the reaction dynamics leading to incomplete fusion of heavy ions at moderate excitation energies. Excitation functions for {sup 168}Lu{sup m}, {sup 167}Lu, {sup 167}Yb, {sup 166}Tm, {sup 179}Re, {sup 177}Re, {sup 177}W, {sup 178}Ta, and {sup 177}Hf radio-nuclides populated via complete and/or incomplete fusion of {sup 16}O with {sup 159}Tb and {sup 169}Tm have been studied over the wide projectile energy range E{sub proj}{approx_equal}75-95 MeV. Recoil-catcher technique followed by off-line {gamma}-spectrometry has been employed in the present measurements. Experimental data have been compared with the predictions of theoretical model code PACE2. The experimentally measured production cross sections of {alpha}-emitting channels were found to be larger as compared to the theoretical model predictions and may be attributed to incomplete fusion at these energies. During the analysis of experimental data, incomplete fusion has been found to be competing with complete fusion. As such, an attempt has been made to estimate the incomplete fusion fraction for both the systems, and has been found to be sensitive for projectile energy and mass asymmetry of interacting partners.

  10. Discovery and Classification of Fusion Transcripts in Prostate Cancer and Normal Prostate Tissue.

    PubMed

    Luo, Jian-Hua; Liu, Silvia; Zuo, Ze-Hua; Chen, Rui; Tseng, George C; Yu, Yan P

    2015-07-01

    Fusion transcript formation is one of the fundamental mechanisms that drives the development of prostate cancer. Because of the advance of high-throughput parallel sequencing, many fusion transcripts have been discovered. However, the discovery rate of fusion transcripts specific for prostate cancer is lagging behind the discoveries made on chromosome abnormalities of prostate cancer. Recent analyses suggest that many fusion transcripts are present in both benign and cancerous tissues. Some of these fusion transcripts likely represent important components of normal gene expression in cells. It is necessary to identify the criteria and features of fusion transcripts that are specific for cancer. In this review, we discuss optimization of RNA sequencing depth for fusion transcript discovery and the characteristics of fusion transcripts in normal prostate tissues and prostate cancer. We also propose a new classification of cancer-specific fusion transcripts on the basis of their tail gene fusion protein product and the roles that these fusions may play in cancer development.

  11. [Early clinical effect of intervertebral fusion of lumbar degenerative disease using nano-hydroxyapatite/polyamide 66 intervertebral fusion cage].

    PubMed

    Yang, Bo; Ou, Yunsheng; Jiang, Dianming; An, Hong; Liu, Bo; Zhang, Jian; Li, Kaiting

    2014-10-01

    The present study is aimed to investigate the early clinical effects of nano-hydroxyapatite/polyamide 66 intervertebral fusion cage (n-HA/PA66 cage) for the treatment of lumbar degenerative diseases. We selected 27 patients with lumbar degenerative diseases who were managed by posterior decompression or reset operation combined with n-HA/PA66 cage intervertebral fusion and internal fixation from August 2010 to January 2012. The oswestry disability index (ODI), low back and leg pain visual analogue score (VAS), and intervertebral height (IH) were evaluated at preoperation, 1 week postoperation and the last follow-up period, respectively. Intervertebral bony fusion was evaluated at the last follow-up time. The patients were followed up for 12-24 months (averaged 19 months). The ODI, VAS and IH were significantly improved at 1 week postoperation and the last follow-up time compared with those at preoperative period (P < 0.05). But there was no significant difference between 1 week postoperative and the last follow-up time (P < 0.05). Brantigan's standard was used to evaluate fusion at the last follow-up time. There were 19 patients with grade 5 fusion, 8 with grade 4 fusion, with a fusion rate of 100%, and none with grade 1-3 fusions. There was no cage translocation and internal fixation breakage. These results suggested that n-HA/PA66 cage was an ideal biological material in the posterior lumbar interbody fusion and internal fixation operation for treatment of lumbar degenerative diseases. It can effectively maintain the intervertebral height and keep a high rate of bony fusion. The early clinical effect has been satisfactory.

  12. Demonstration of thermonuclear conditions in magnetized liner inertial fusion experimentsa)

    NASA Astrophysics Data System (ADS)

    Gomez, M. R.; Slutz, S. A.; Sefkow, A. B.; Hahn, K. D.; Hansen, S. B.; Knapp, P. F.; Schmit, P. F.; Ruiz, C. L.; Sinars, D. B.; Harding, E. C.; Jennings, C. A.; Awe, T. J.; Geissel, M.; Rovang, D. C.; Smith, I. C.; Chandler, G. A.; Cooper, G. W.; Cuneo, M. E.; Harvey-Thompson, A. J.; Herrmann, M. C.; Hess, M. H.; Lamppa, D. C.; Martin, M. R.; McBride, R. D.; Peterson, K. J.; Porter, J. L.; Rochau, G. A.; Savage, M. E.; Schroen, D. G.; Stygar, W. A.; Vesey, R. A.

    2015-05-01

    The magnetized liner inertial fusion concept [S. A. Slutz et al., Phys. Plasmas 17, 056303 (2010)] utilizes a magnetic field and laser heating to relax the pressure requirements of inertial confinement fusion. The first experiments to test the concept [M. R. Gomez et al., Phys. Rev. Lett. 113, 155003 (2014)] were conducted utilizing the 19 MA, 100 ns Z machine, the 2.5 kJ, 1 TW Z Beamlet laser, and the 10 T Applied B-field on Z system. Despite an estimated implosion velocity of only 70 km/s in these experiments, electron and ion temperatures at stagnation were as high as 3 keV, and thermonuclear deuterium-deuterium neutron yields up to 2 × 1012 have been produced. X-ray emission from the fuel at stagnation had widths ranging from 50 to 110 μm over a roughly 80% of the axial extent of the target (6-8 mm) and lasted approximately 2 ns. X-ray yields from these experiments are consistent with a stagnation density of the hot fuel equal to 0.2-0.4 g/cm3. In these experiments, up to 5 × 1010 secondary deuterium-tritium neutrons were produced. Given that the areal density of the plasma was approximately 1-2 mg/cm2, this indicates the stagnation plasma was significantly magnetized, which is consistent with the anisotropy observed in the deuterium-tritium neutron spectra. Control experiments where the laser and/or magnetic field were not utilized failed to produce stagnation temperatures greater than 1 keV and primary deuterium-deuterium yields greater than 1010. An additional control experiment where the fuel contained a sufficient dopant fraction to substantially increase radiative losses also failed to produce a relevant stagnation temperature. The results of these experiments are consistent with a thermonuclear neutron source.

  13. Demonstration of thermonuclear conditions in magnetized liner inertial fusion experiments

    DOE PAGES

    Gomez, Matthew R.; Slutz, Stephen A.; Sefkow, Adam B.; ...

    2015-04-29

    In this study, the magnetized liner inertial fusion concept [S. A. Slutz et al., Phys. Plasmas17, 056303 (2010)] utilizes a magnetic field and laser heating to relax the pressure requirements of inertial confinement fusion. The first experiments to test the concept [M. R. Gomez et al., Phys. Rev. Lett. 113, 155003 (2014)] were conducted utilizing the 19 MA, 100 ns Z machine, the 2.5 kJ, 1 TW Z Beamlet laser, and the 10 T Applied B-field on Z system. Despite an estimated implosion velocity of only 70 km/s in these experiments, electron and ion temperatures at stagnation were as highmore » as 3 keV, and thermonuclear deuterium-deuterium neutron yields up to 2 × 1012 have been produced. X-ray emission from the fuel at stagnation had widths ranging from 50 to 110 μm over a roughly 80% of the axial extent of the target (6–8 mm) and lasted approximately 2 ns. X-ray yields from these experiments are consistent with a stagnation density of the hot fuel equal to 0.2–0.4 g/cm3. In these experiments, up to 5 ×1010 secondary deuterium-tritium neutrons were produced. Given that the areal density of the plasma was approximately 1–2 mg/cm2, this indicates the stagnation plasma was significantly magnetized, which is consistent with the anisotropy observed in the deuterium-tritium neutron spectra. Control experiments where the laser and/or magnetic field were not utilized failed to produce stagnation temperatures greater than 1 keV and primary deuterium-deuterium yields greater than 1010. An additional control experiment where the fuel contained a sufficient dopant fraction to substantially increase radiative losses also failed to produce a relevant stagnation temperature. The results of these experiments are consistent with a thermonuclear neutron source.« less

  14. Inner membrane fusion mediates spatial distribution of axonal mitochondria

    PubMed Central

    Yu, Yiyi; Lee, Hao-Chih; Chen, Kuan-Chieh; Suhan, Joseph; Qiu, Minhua; Ba, Qinle; Yang, Ge

    2016-01-01

    In eukaryotic cells, mitochondria form a dynamic interconnected network to respond to changing needs at different subcellular locations. A fundamental yet unanswered question regarding this network is whether, and if so how, local fusion and fission of individual mitochondria affect their global distribution. To address this question, we developed high-resolution computational image analysis techniques to examine the relations between mitochondrial fusion/fission and spatial distribution within the axon of Drosophila larval neurons. We found that stationary and moving mitochondria underwent fusion and fission regularly but followed different spatial distribution patterns and exhibited different morphology. Disruption of inner membrane fusion by knockdown of dOpa1, Drosophila Optic Atrophy 1, not only increased the spatial density of stationary and moving mitochondria but also changed their spatial distributions and morphology differentially. Knockdown of dOpa1 also impaired axonal transport of mitochondria. But the changed spatial distributions of mitochondria resulted primarily from disruption of inner membrane fusion because knockdown of Milton, a mitochondrial kinesin-1 adapter, caused similar transport velocity impairment but different spatial distributions. Together, our data reveals that stationary mitochondria within the axon interconnect with moving mitochondria through fusion and fission and that local inner membrane fusion between individual mitochondria mediates their global distribution. PMID:26742817

  15. Inner membrane fusion mediates spatial distribution of axonal mitochondria.

    PubMed

    Yu, Yiyi; Lee, Hao-Chih; Chen, Kuan-Chieh; Suhan, Joseph; Qiu, Minhua; Ba, Qinle; Yang, Ge

    2016-01-08

    In eukaryotic cells, mitochondria form a dynamic interconnected network to respond to changing needs at different subcellular locations. A fundamental yet unanswered question regarding this network is whether, and if so how, local fusion and fission of individual mitochondria affect their global distribution. To address this question, we developed high-resolution computational image analysis techniques to examine the relations between mitochondrial fusion/fission and spatial distribution within the axon of Drosophila larval neurons. We found that stationary and moving mitochondria underwent fusion and fission regularly but followed different spatial distribution patterns and exhibited different morphology. Disruption of inner membrane fusion by knockdown of dOpa1, Drosophila Optic Atrophy 1, not only increased the spatial density of stationary and moving mitochondria but also changed their spatial distributions and morphology differentially. Knockdown of dOpa1 also impaired axonal transport of mitochondria. But the changed spatial distributions of mitochondria resulted primarily from disruption of inner membrane fusion because knockdown of Milton, a mitochondrial kinesin-1 adapter, caused similar transport velocity impairment but different spatial distributions. Together, our data reveals that stationary mitochondria within the axon interconnect with moving mitochondria through fusion and fission and that local inner membrane fusion between individual mitochondria mediates their global distribution.

  16. Inner membrane fusion mediates spatial distribution of axonal mitochondria

    NASA Astrophysics Data System (ADS)

    Yu, Yiyi; Lee, Hao-Chih; Chen, Kuan-Chieh; Suhan, Joseph; Qiu, Minhua; Ba, Qinle; Yang, Ge

    2016-01-01

    In eukaryotic cells, mitochondria form a dynamic interconnected network to respond to changing needs at different subcellular locations. A fundamental yet unanswered question regarding this network is whether, and if so how, local fusion and fission of individual mitochondria affect their global distribution. To address this question, we developed high-resolution computational image analysis techniques to examine the relations between mitochondrial fusion/fission and spatial distribution within the axon of Drosophila larval neurons. We found that stationary and moving mitochondria underwent fusion and fission regularly but followed different spatial distribution patterns and exhibited different morphology. Disruption of inner membrane fusion by knockdown of dOpa1, Drosophila Optic Atrophy 1, not only increased the spatial density of stationary and moving mitochondria but also changed their spatial distributions and morphology differentially. Knockdown of dOpa1 also impaired axonal transport of mitochondria. But the changed spatial distributions of mitochondria resulted primarily from disruption of inner membrane fusion because knockdown of Milton, a mitochondrial kinesin-1 adapter, caused similar transport velocity impairment but different spatial distributions. Together, our data reveals that stationary mitochondria within the axon interconnect with moving mitochondria through fusion and fission and that local inner membrane fusion between individual mitochondria mediates their global distribution.

  17. Disassembly of the fusion-1 capsule after irradiation in the BOR-60 reactor

    SciTech Connect

    Tsai, H.; Kazakov, V.A.; Chakin, V.P.

    1997-04-01

    A U.S./Russia (RF) collaborative irradiation experiment, Fusion-1, was completed in June 1996 after reaching a peak exposure of {approx}17 dpa in the BOR-60 fast reactor at the Research Institute of Atomic Reactors (RIAR) in Russia. The specimens were vanadium alloys, mainly of recent heats from both countries. In this reporting period, the capsule was disassembled at the RIAR hot cells and all test specimens were successfully retrieved. For the disassembly, an innovative method of using a heated diffusion oil to melt and separate the lithium bond from the test specimens was adopted. This method proved highly successful.

  18. The Multifaceted Role of SNARE Proteins in Membrane Fusion.

    PubMed

    Han, Jing; Pluhackova, Kristyna; Böckmann, Rainer A

    2017-01-01

    Membrane fusion is a key process in all living organisms that contributes to a variety of biological processes including viral infection, cell fertilization, as well as intracellular transport, and neurotransmitter release. In particular, the various membrane-enclosed compartments in eukaryotic cells need to exchange their contents and communicate across membranes. Efficient and controllable fusion of biological membranes is known to be driven by cooperative action of SNARE proteins, which constitute the central components of the eukaryotic fusion machinery responsible for fusion of synaptic vesicles with the plasma membrane. During exocytosis, vesicle-associated v-SNARE (synaptobrevin) and target cell-associated t-SNAREs (syntaxin and SNAP-25) assemble into a core trans-SNARE complex. This complex plays a versatile role at various stages of exocytosis ranging from the priming to fusion pore formation and expansion, finally resulting in the release or exchange of the vesicle content. This review summarizes current knowledge on the intricate molecular mechanisms underlying exocytosis triggered and catalyzed by SNARE proteins. Particular attention is given to the function of the peptidic SNARE membrane anchors and the role of SNARE-lipid interactions in fusion. Moreover, the regulatory mechanisms by synaptic auxiliary proteins in SNARE-driven membrane fusion are briefly outlined.

  19. The Multifaceted Role of SNARE Proteins in Membrane Fusion

    PubMed Central

    Han, Jing; Pluhackova, Kristyna; Böckmann, Rainer A.

    2017-01-01

    Membrane fusion is a key process in all living organisms that contributes to a variety of biological processes including viral infection, cell fertilization, as well as intracellular transport, and neurotransmitter release. In particular, the various membrane-enclosed compartments in eukaryotic cells need to exchange their contents and communicate across membranes. Efficient and controllable fusion of biological membranes is known to be driven by cooperative action of SNARE proteins, which constitute the central components of the eukaryotic fusion machinery responsible for fusion of synaptic vesicles with the plasma membrane. During exocytosis, vesicle-associated v-SNARE (synaptobrevin) and target cell-associated t-SNAREs (syntaxin and SNAP-25) assemble into a core trans-SNARE complex. This complex plays a versatile role at various stages of exocytosis ranging from the priming to fusion pore formation and expansion, finally resulting in the release or exchange of the vesicle content. This review summarizes current knowledge on the intricate molecular mechanisms underlying exocytosis triggered and catalyzed by SNARE proteins. Particular attention is given to the function of the peptidic SNARE membrane anchors and the role of SNARE-lipid interactions in fusion. Moreover, the regulatory mechanisms by synaptic auxiliary proteins in SNARE-driven membrane fusion are briefly outlined. PMID:28163686

  20. BOOK REVIEW: Fundamentals of Plasma Physics and Controlled Fusion

    NASA Astrophysics Data System (ADS)

    Brambilla, Marco

    1998-04-01

    general part concludes with a few chapters on waves, again covering a broad spectrum of topics in a very condensed form: cold plasma waves, Landau and cyclotron absorption, quasi-linear theory, power flow and ray tracing in non-uniform plasmas, the main radiofrequency heating scenarios (ion cyclotron, lower hybrid and electron cyclotron) and the most common velocity space instabilities. The second part describes tokamaks, reversed field pinches, stellarators and open ended systems, and ends with a short chapter on inertial fusion. Although more descriptive in nature, this part offers a succinct introduction to relatively advanced topics, particularly for the tokamak: MHD stability and density limits, non-inductive current drive, bootstrap current, improved confinement regimes and scaling laws of the confinement. Reference to the first, general part, allows an introduction to and explanation of many of the formulas in current use for the interpretation of experimental results. A nice feature of this part is also the concise but very readable introduction to the history of fusion research. The level of the presentation corresponds well to what one would expect in a course for postgraduate students: most topics are discussed rather briefly, but always quantitatively, the mathematics being mostly worked out in full. As should be clear from the description of the content, there is a strong bias towards concrete applications, at the expense of general principles: this goes so far that the derivation of the energy principle for ideal MHD instabilities and of the dielectric tensor of the hot plasma are relegated to appendices, in spite of the fact that the mathematics involved is by no means more complex than that of the applications discussed in the main text. The equations of magnetohydrodynamics are derived in Chapter 5 not as a particular closure of the hierarchy of moments of the Vlasov equation, but using a phenomenological approach. The space devoted to comments and

  1. Dilation of fusion pores by crowding of SNARE proteins.

    PubMed

    Wu, Zhenyong; Bello, Oscar D; Thiyagarajan, Sathish; Auclair, Sarah Marie; Vennekate, Wensi; Krishnakumar, Shyam S; O'Shaughnessy, Ben; Karatekin, Erdem

    2017-03-27

    Hormones and neurotransmitters are released through fluctuating exocytotic fusion pores that can flicker open and shut multiple times. Cargo release and vesicle recycling depend on the fate of the pore, which may reseal or dilate irreversibly. Pore nucleation requires zippering between vesicle-associated v- and target membrane t-SNAREs, but the mechanisms governing the subsequent pore dilation are not understood. Here, we probed dilation of single fusion pores using v-SNARE-reconstituted ~23 nm diameter discoidal nanolipoprotein particles (vNLPs) as fusion partners with cells ectopically expressing cognate, 'flipped' t-SNAREs. Pore nucleation required a minimum of 2, and reached a maximum above ~4 copies per face, but the probability of pore dilation was far from saturating at 15 copies, the NLP capacity. Our experimental and computational results suggest SNARE availability may be pivotal in determining whether neurotransmitters or hormones are released through a transient (kiss & run) or an irreversibly dilating pore (full fusion).

  2. Environmental and safety issues of the fusion fuel cycle

    SciTech Connect

    Crocker, J.G.

    1980-01-01

    This paper discusses the environmental and safety concerns inherent in the development of fusion energy, and the current Department of Energy programs seeking to: (1) develop safe and reliable techniques for tritium control; (2) reduce the quantity of activation products produced; and (3) provide designs to limit the potential for accidents that could result in release of radioactive materials. Because of the inherent safety features of fusion and the early start that has been made in safety problem recognition and solution, fusion should be among the lower risk technologies for generation of commercial power.

  3. The Mechanism of Henipavirus Fusion: Examining the Relationships between the Attachment and Fusion Glycoproteins

    DTIC Science & Technology

    2009-04-01

    class ephrin protein receptor triggering conformational alterations leading to the activation of the viral fusion (F) glycoprotein. The analysis of...membrane proteins with the molecule’s amino (N)-terminus oriented towards the cytoplasm and the protein’s carboxy (C)-terminus facing the...henipavirus G glycoprotein, contain a globular head domain, a stalk region, transmembrane domain, and a short cytoplasmic tail (9, 57) The

  4. Overexpression of calpastatin inhibits L8 myoblast fusion

    SciTech Connect

    Barnoy, Sivia; E-mail: sivia@post.tau.ac.il; Maki, Masatoshi; Kosower, Nechama S.

    2005-07-08

    The formation of skeletal muscle fibers involves cessation of myoblast division, myoblast alignment, and fusion to multinucleated myofibers. Calpain is one of the factors shown to be involved in myoblast fusion. Using L8 rat myoblasts, we found that calpain levels did not change significantly during myoblast differentiation, whereas calpastatin diminished prior to myoblast fusion and reappeared after fusion. The transient diminution in calpastatin allows the Ca{sup 2+}-promoted activation of calpain and calpain-induced membrane proteolysis, which is required for myoblast fusion. Here we show that calpastatin overexpression in L8 myoblasts does not inhibit cell proliferation and alignment, but prevents myoblast fusion and fusion-associated protein degradation. In addition, calpastatin appears to modulate myogenic gene expression, as indicated by the lack of myogenin (a transcription factor expressed in differentiating myoblasts) in myoblasts overexpressing calpastatin. These results suggest that, in addition to the role in membrane disorganization in the fusing myoblasts, the calpain-calpastatin system may also modulate the levels of factors required for myoblast differentiation.

  5. Fusion research at ORNL

    SciTech Connect

    Not Available

    1982-03-01

    The ORNL Fusion Program includes the experimental and theoretical study of two different classes of magnetic confinement schemes - systems with helical magnetic fields, such as the tokamak and stellarator, and the ELMO Bumpy Torus (EBT) class of toroidally linked mirror systems; the development of technologies, including superconducting magnets, neutral atomic beam and radio frequency (rf) heating systems, fueling systems, materials, and diagnostics; the development of databases for atomic physics and radiation effects; the assessment of the environmental impact of magnetic fusion; and the design of advanced demonstration fusion devices. The program involves wide collaboration, both within ORNL and with other institutions. The elements of this program are shown. This document illustrates the program's scope; and aims by reviewing recent progress.

  6. Management of adjacent segment disease after cervical spinal fusion.

    PubMed

    Kepler, Christopher K; Hilibrand, Alan S

    2012-01-01

    Adjacent segment disease (ASD) was described after long-term follow-up of patients treated with cervical fusion. The term describes new-onset radiculopathy or myelopathy referable to a motion segment adjacent to previous arthrodesis and often attributed to alterations in the biomechanical environment after fusion. Evidence suggests that ASD affects between 2% and 3% of patients per year. Although prevention of ASD was one major impetus behind the development of motion-sparing surgery, the literature does not yet clearly distinguish a difference in the rate of ASD between fusion and disk replacement. Surgical techniques during index surgery may reduce the rate of ASD.

  7. Molecular mechanism of Ca(2+)-catalyzed fusion of phospholipid micelles.

    PubMed

    Tsai, Hui-Hsu Gavin; Juang, Wei-Fu; Chang, Che-Ming; Hou, Tsai-Yi; Lee, Jian-Bin

    2013-11-01

    Although membrane fusion plays key roles in intracellular trafficking, neurotransmitter release, and viral infection, its underlying molecular mechanism and its energy landscape are not well understood. In this study, we employed all-atom molecular dynamics simulations to investigate the fusion mechanism, catalyzed by Ca(2+) ions, of two highly hydrated 1-palmitoyl-2-oleoyl-sn-3-phosphoethanolamine (POPE) micelles. This simulation system mimics the small contact zone between two large vesicles at which the fusion is initiated. Our simulations revealed that Ca(2+) ions are capable of catalyzing the fusion of POPE micelles; in contrast, we did not observe close contact of the two micelles in the presence of only Na(+) or Mg(2+) ions. Determining the free energy landscape of fusion allowed us to characterize the underlying molecular mechanism. The Ca(2+) ions play a key role in catalyzing the micelle fusion in three aspects: creating a more-hydrophobic surface on the micelles, binding two micelles together, and enhancing the formation of the pre-stalk state. In contrast, Na(+) or Mg(2+) ions have relatively limited effects. Effective fusion proceeds through sequential formation of pre-stalk, stalk, hemifused-like, and fused states. The pre-stalk state is the state featuring lipid tails exposed to the inter-micellar space; its formation is the rate-limiting step. The stalk state is the state where a localized hydrophobic core is formed connecting two micelles; its formation occurs in conjunction with water expulsion from the inter-micellar space. This study provides insight into the molecular mechanism of fusion from the points of view of energetics, structure, and dynamics.

  8. Welcome Back: Responses of Female Bonobos (Pan paniscus) to Fusions.

    PubMed

    Moscovice, Liza R; Deschner, Tobias; Hohmann, Gottfried

    2015-01-01

    In species with a high degree of fission-fusion social dynamics, fusions may trigger social conflict and thus provide an opportunity to identify sources of social tension and mechanisms related to its alleviation. We characterized behavioral and endocrine responses of captive female bonobos (Pan paniscus) to fusions within a zoo facility designed to simulate naturalistic fission-fusion social dynamics. We compared urinary cortisol levels and frequencies of aggression, grooming and socio-sexual interactions between female bonobos while in stable sub-groups and when one "joiner" was reunited with the "residents" of another sub-group. We hypothesized that fusions would trigger increases in aggression and cortisol levels among reunited joiners and resident females. We further predicted that females who face more uncertainty in their social interactions following fusions may use grooming and/or socio-sexual behavior to reduce social tension and aggression. The only aggression on reunion days occurred between reunited females, but frequencies of aggression remained low across non-reunion and reunion days, and there was no effect of fusions on cortisol levels. Fusions did not influence patterns of grooming, but there were increases in socio-sexual solicitations and socio-sexual interactions between joiners and resident females. Joiners who had been separated from residents for longer received the most solicitations, but were also more selective in their acceptance of solicitations and preferred to have socio-sexual interactions with higher-ranking residents. Our results suggest that socio-sexual interactions play a role in reintegrating female bonobos into social groups following fusions. In addition, females who receive a high number of solicitations are able to gain more control over their socio-sexual interactions and may use socio-sexual interactions for other purposes, such as to enhance their social standing.

  9. Welcome Back: Responses of Female Bonobos (Pan paniscus) to Fusions

    PubMed Central

    Moscovice, Liza R.; Deschner, Tobias; Hohmann, Gottfried

    2015-01-01

    In species with a high degree of fission-fusion social dynamics, fusions may trigger social conflict and thus provide an opportunity to identify sources of social tension and mechanisms related to its alleviation. We characterized behavioral and endocrine responses of captive female bonobos (Pan paniscus) to fusions within a zoo facility designed to simulate naturalistic fission-fusion social dynamics. We compared urinary cortisol levels and frequencies of aggression, grooming and socio-sexual interactions between female bonobos while in stable sub-groups and when one “joiner” was reunited with the “residents” of another sub-group. We hypothesized that fusions would trigger increases in aggression and cortisol levels among reunited joiners and resident females. We further predicted that females who face more uncertainty in their social interactions following fusions may use grooming and/or socio-sexual behavior to reduce social tension and aggression. The only aggression on reunion days occurred between reunited females, but frequencies of aggression remained low across non-reunion and reunion days, and there was no effect of fusions on cortisol levels. Fusions did not influence patterns of grooming, but there were increases in socio-sexual solicitations and socio-sexual interactions between joiners and resident females. Joiners who had been separated from residents for longer received the most solicitations, but were also more selective in their acceptance of solicitations and preferred to have socio-sexual interactions with higher-ranking residents. Our results suggest that socio-sexual interactions play a role in reintegrating female bonobos into social groups following fusions. In addition, females who receive a high number of solicitations are able to gain more control over their socio-sexual interactions and may use socio-sexual interactions for other purposes, such as to enhance their social standing. PMID:25996476

  10. Comparison of Semidistributed Multinode TOA-DOA Fusion Localization and GPS-Aided TOA (DOA) Fusion Localization for MANETs

    NASA Astrophysics Data System (ADS)

    Wang, Zhonghai; Zekavat, Seyed

    2008-12-01

    This paper evaluates the performance of a semidistributed multinode time-of-arrival (TOA) and direction-of-arrival (DOA) fusion localization technique in terms of localization circular error probability (CEP). The localization technique is applicable in mobile ad hoc networks (MANETs) when global positioning system (GPS) is not available (GPS denied environments). The localization CEP of the technique is derived theoretically and verified via simulations. In addition, we theoretically derive the localization CEP of GPS-aided TOA fusion and GPS-aided DOA fusion techniques, which are also applicable in MANETs. Finally, we compare these three localization techniques theoretically and via simulations. The comparison confirms that in moderate scale MANETs, the multinode TOA-DOA fusion localization technique achieves the best performance; while in large scale MANETs, GPS-aided TOA fusion leads to the best performance.

  11. Impact of physics and technology innovations on compact tokamak fusion pilot plants

    NASA Astrophysics Data System (ADS)

    Menard, Jonathan

    2016-10-01

    For magnetic fusion to be economically attractive and have near-term impact on the world energy scene it is important to focus on key physics and technology innovations that could enable net electricity production at reduced size and cost. The tokamak is presently closest to achieving the fusion conditions necessary for net electricity at acceptable device size, although sustaining high-performance scenarios free of disruptions remains a significant challenge for the tokamak approach. Previous pilot plant studies have shown that electricity gain is proportional to the product of the fusion gain, blanket thermal conversion efficiency, and auxiliary heating wall-plug efficiency. In this work, the impact of several innovations is assessed with respect to maximizing fusion gain. At fixed bootstrap current fraction, fusion gain varies approximately as the square of the confinement multiplier, normalized beta, and major radius, and varies as the toroidal field and elongation both to the third power. For example, REBCO high-temperature superconductors (HTS) offer the potential to operate at much higher toroidal field than present fusion magnets, but HTS cables are also beginning to access winding pack current densities up to an order of magnitude higher than present technology, and smaller HTS TF magnet sizes make low-aspect-ratio HTS tokamaks potentially attractive by leveraging naturally higher normalized beta and elongation. Further, advances in kinetic stabilization and feedback control of resistive wall modes could also enable significant increases in normalized beta and fusion gain. Significant reductions in pilot plant size will also likely require increased plasma energy confinement, and control of turbulence and/or low edge recycling (for example using lithium walls) would have major impact on fusion gain. Reduced device size could also exacerbate divertor heat loads, and the impact of novel divertor solutions on pilot plant configurations is addressed. For

  12. Laser inertial fusion-based energy: Neutronic design aspects of a hybrid fusion-fission nuclear energy system

    NASA Astrophysics Data System (ADS)

    Kramer, Kevin James

    This study investigates the neutronics design aspects of a hybrid fusion-fission energy system called the Laser Fusion-Fission Hybrid (LFFH). A LFFH combines current Laser Inertial Confinement fusion technology with that of advanced fission reactor technology to produce a system that eliminates many of the negative aspects of pure fusion or pure fission systems. When examining the LFFH energy mission, a significant portion of the United States and world energy production could be supplied by LFFH plants. The LFFH engine described utilizes a central fusion chamber surrounded by multiple layers of multiplying and moderating media. These layers, or blankets, include coolant plenums, a beryllium (Be) multiplier layer, a fertile fission blanket and a graphite-pebble reflector. Each layer is separated by perforated oxide dispersion strengthened (ODS) ferritic steel walls. The central fusion chamber is surrounded by an ODS ferritic steel first wall. The first wall is coated with 250-500 mum of tungsten to mitigate x-ray damage. The first wall is cooled by Li17Pb83 eutectic, chosen for its neutron multiplication and good heat transfer properties. The Li17Pb 83 flows in a jacket around the first wall to an extraction plenum. The main coolant injection plenum is immediately behind the Li17Pb83, separated from the Li17Pb83 by a solid ODS wall. This main system coolant is the molten salt flibe (2LiF-BeF2), chosen for beneficial neutronics and heat transfer properties. The use of flibe enables both fusion fuel production (tritium) and neutron moderation and multiplication for the fission blanket. A Be pebble (1 cm diameter) multiplier layer surrounds the coolant injection plenum and the coolant flows radially through perforated walls across the bed. Outside the Be layer, a fission fuel layer comprised of depleted uranium contained in Tristructural-isotropic (TRISO) fuel particles having a packing fraction of 20% in 2 cm diameter fuel pebbles. The fission blanket is cooled by

  13. Safety of magnetic fusion facilities: Volume 2, Guidance

    SciTech Connect

    1995-07-01

    This document provides guidance for the implementation of the requirements identified in Vol. 1 of this Standard. This guidance is intended for the managers, designers, operators, and other personnel with safety responsibilities for facilities designated as magnetic fusion facilities. While Vol. 1 is generally applicable in that requirements there apply to a wide range of fusion facilities, this volume is concerned mainly with large facilities such as the International Thermonuclear Experimental Reactor (ITER). Using a risk-based prioritization, the concepts presented here may also be applied to other magnetic fusion facilities. This volume is oriented toward regulation in the Department of Energy (DOE) environment.

  14. The MARVEL domain protein, Singles Bar, is required for progression past the pre-fusion complex stage of myoblast fusion

    PubMed Central

    Estrada, Beatriz; Maeland, Anne D.; Gisselbrecht, Stephen S.; Bloor, James W.; Brown, Nicholas H.; Michelson, Alan M.

    2007-01-01

    Summary Multinucleated myotubes develop by the sequential fusion of individual myoblasts. Using a convergence of genomic and classical genetic approaches, we have discovered a novel gene, singles bar (sing), that is essential for myoblast fusion. sing encodes a small multipass transmembrane protein containing a MARVEL domain, which is found in vertebrate proteins involved in processes such as tight junction formation and vesicle trafficking where—as in myoblast fusion—membrane apposition occurs. sing is expressed in both founder cells and fusion competent myoblasts preceding and during myoblast fusion. Examination of embryos injected with double-stranded sing RNA or embryos homozygous for ethane methyl sulfonate-induced sing alleles revealed an identical phenotype: replacement of multinucleated myofibers by groups of single, myosin-expressing myoblasts at a stage when formation of the mature muscle pattern is complete in wild-type embryos. Unfused sing mutant myoblasts form clusters, suggesting that early recognition and adhesion of these cells is unimpaired. To further investigate this phenotype, we undertook electron microscopic ultrastructural studies of fusing myoblasts in both sing and wild-type embryos. These experiments revealed that more sing mutant myoblasts than wild-type contain pre-fusion complexes, which are characterized by electron-dense vesicles paired on either side of the fusing plasma membranes. In contrast, embryos mutant for another muscle fusion gene, blown fuse (blow), have a normal number of such complexes. Together, these results lead to the hypothesis that sing acts at a step distinct from that of blow, and that sing is required on both founder cell and fusion-competent myoblast membranes to allow progression past the pre-fusion complex stage of myoblast fusion, possibly by mediating fusion of the electron-dense vesicles to the plasma membrane. PMID:17537424

  15. Report of the Fusion Energy Sciences Advisory Committee. Panel on Integrated Simulation and Optimization of Magnetic Fusion Systems

    SciTech Connect

    Dahlburg, Jill; Corones, James; Batchelor, Donald; Bramley, Randall; Greenwald, Martin; Jardin, Stephen; Krasheninnikov, Sergei; Laub, Alan; Leboeuf, Jean-Noel; Lindl, John; Lokke, William; Rosenbluth, Marshall; Ross, David; Schnack, Dalton

    2002-11-01

    Fusion is potentially an inexhaustible energy source whose exploitation requires a basic understanding of high-temperature plasmas. The development of a science-based predictive capability for fusion-relevant plasmas is a challenge central to fusion energy science, in which numerical modeling has played a vital role for more than four decades. A combination of the very wide range in temporal and spatial scales, extreme anisotropy, the importance of geometric detail, and the requirement of causality which makes it impossible to parallelize over time, makes this problem one of the most challenging in computational physics. Sophisticated computational models are under development for many individual features of magnetically confined plasmas and increases in the scope and reliability of feasible simulations have been enabled by increased scientific understanding and improvements in computer technology. However, full predictive modeling of fusion plasmas will require qualitative improvements and innovations to enable cross coupling of a wider variety of physical processes and to allow solution over a larger range of space and time scales. The exponential growth of computer speed, coupled with the high cost of large-scale experimental facilities, makes an integrated fusion simulation initiative a timely and cost-effective opportunity. Worldwide progress in laboratory fusion experiments provides the basis for a recent FESAC recommendation to proceed with a burning plasma experiment (see FESAC Review of Burning Plasma Physics Report, September 2001). Such an experiment, at the frontier of the physics of complex systems, would be a huge step in establishing the potential of magnetic fusion energy to contribute to the world’s energy security. An integrated simulation capability would dramatically enhance the utilization of such a facility and lead to optimization of toroidal fusion plasmas in general. This science-based predictive capability, which was cited in the FESAC

  16. Variable control of neutron albedo in toroidal fusion devices

    DOEpatents

    Jassby, Daniel L.; Micklich, Bradley J.

    1986-01-01

    An arrangement is provided for controlling neutron albedo in toroidal fusion devices having inboard and outboard vacuum vessel walls for containment of the neutrons of a fusion plasma. Neutron albedo material is disposed immediately adjacent the inboard wall, and is movable, preferably in vertical directions, so as to be brought into and out of neutron modifying communication with the fusion neutrons. Neutron albedo material preferably comprises a liquid form, but may also take pebble, stringer and curtain-like forms. A neutron flux valve, rotatable about a vertical axis is also disclosed.

  17. Design of the 1.5 MW, 30-96 MHz ultra-wideband 3 dB high power hybrid coupler for Ion Cyclotron Resonance Frequency (ICRF) heating in fusion grade reactor

    SciTech Connect

    Yadav, Rana Pratap Kumar, Sunil; Kulkarni, S. V.

    2016-01-15

    Design and developmental procedure of strip-line based 1.5 MW, 30-96 MHz, ultra-wideband high power 3 dB hybrid coupler has been presented and its applicability in ion cyclotron resonance heating (ICRH) in tokamak is discussed. For the high power handling capability, spacing between conductors and ground need to very high. Hence other structural parameters like strip-width, strip thickness coupling gap, and junction also become large which can be gone upto optimum limit where various constrains like fabrication tolerance, discontinuities, and excitation of higher TE and TM modes become prominent and significantly deteriorates the desired parameters of the coupled lines system. In designed hybrid coupler, two 8.34 dB coupled lines are connected in tandem to get desired coupling of 3 dB and air is used as dielectric. The spacing between ground and conductors are taken as 0.164 m for 1.5 MW power handling capability. To have the desired spacing, each of 8.34 dB segments are designed with inner dimension of 3.6 × 1.0 × 40 cm where constraints have been significantly realized, compensated, and applied in designing of 1.5 MW hybrid coupler and presented in paper.

  18. Benchmarking of data fusion algorithms in support of earth observation based Antarctic wildlife monitoring

    NASA Astrophysics Data System (ADS)

    Witharana, Chandi; LaRue, Michelle A.; Lynch, Heather J.

    2016-03-01

    Remote sensing is a rapidly developing tool for mapping the abundance and distribution of Antarctic wildlife. While both panchromatic and multispectral imagery have been used in this context, image fusion techniques have received little attention. We tasked seven widely-used fusion algorithms: Ehlers fusion, hyperspherical color space fusion, high-pass fusion, principal component analysis (PCA) fusion, University of New Brunswick fusion, and wavelet-PCA fusion to resolution enhance a series of single-date QuickBird-2 and Worldview-2 image scenes comprising penguin guano, seals, and vegetation. Fused images were assessed for spectral and spatial fidelity using a variety of quantitative quality indicators and visual inspection methods. Our visual evaluation elected the high-pass fusion algorithm and the University of New Brunswick fusion algorithm as best for manual wildlife detection while the quantitative assessment suggested the Gram-Schmidt fusion algorithm and the University of New Brunswick fusion algorithm as best for automated classification. The hyperspherical color space fusion algorithm exhibited mediocre results in terms of spectral and spatial fidelities. The PCA fusion algorithm showed spatial superiority at the expense of spectral inconsistencies. The Ehlers fusion algorithm and the wavelet-PCA algorithm showed the weakest performances. As remote sensing becomes a more routine method of surveying Antarctic wildlife, these benchmarks will provide guidance for image fusion and pave the way for more standardized products for specific types of wildlife surveys.

  19. Investigation of materials for fusion power reactors

    NASA Astrophysics Data System (ADS)

    Bouhaddane, A.; Slugeň, V.; Sojak, S.; Veterníková, J.; Petriska, M.; Bartošová, I.

    2014-06-01

    The possibility of application of nuclear-physical methods to observe radiation damage to structural materials of nuclear facilities is nowadays a very actual topic. The radiation damage to materials of advanced nuclear facilities, caused by extreme radiation stress, is a process, which significantly limits their operational life as well as their safety. In the centre of our interest is the study of the radiation degradation and activation of the metals and alloys for the new nuclear facilities (Generation IV fission reactors, fusion reactors ITER and DEMO). The observation of the microstructure changes in the reactor steels is based on experimental investigation using the method of positron annihilation spectroscopy (PAS). The experimental part of the work contains measurements focused on model reactor alloys and ODS steels. There were 12 model reactor steels and 3 ODS steels. We were investigating the influence of chemical composition on the production of defects in crystal lattice. With application of the LT 9 program, the spectra of specimen have been evaluated and the most convenient samples have been determined.

  20. Fusion of Dependent and Independent Biometric Information Sources

    DTIC Science & Technology

    2005-03-01

    recognition. A novel Borda count for fusion based on ranks and confidence was proposed. All experiments were performed on real-world handwritten words...r k r j kjRM xg 2 21 1 21 1 1 0 .))(( )( ),( Λ Λ xα xα α αα Experiments showed that the fusion methods can improve the performance of person...fusing three biometrics DRDC Ottawa CR 2005-052 39 6.4 Soft decision-level fusion The sixth experiment shows the FRR and FAR of the

  1. Magnetic reconnection in plasma under inertial confinement fusion conditions driven by heat flux effects in Ohm's law.

    PubMed

    Joglekar, A S; Thomas, A G R; Fox, W; Bhattacharjee, A

    2014-03-14

    In the interaction of high-power laser beams with solid density plasma there are a number of mechanisms that generate strong magnetic fields. Such fields subsequently inhibit or redirect electron flows, but can themselves be advected by heat fluxes, resulting in complex interplay between thermal transport and magnetic fields. We show that for heating by multiple laser spots reconnection of magnetic field lines can occur, mediated by these heat fluxes, using a fully implicit 2D Vlasov-Fokker-Planck code. Under such conditions, the reconnection rate is dictated by heat flows rather than Alfvènic flows. We find that this mechanism is only relevant in a high β plasma. However, the Hall parameter ωcτei can be large so that thermal transport is strongly modified by these magnetic fields, which can impact longer time scale temperature homogeneity and ion dynamics in the system.

  2. Accident consequences analysis of the HYLIFE-II inertial fusion energy power plant design

    SciTech Connect

    Reyes, S; Gomez del Rio, J; Sanz, J

    2000-02-23

    Previous studies of the safety and environmental (S and E) aspects of the HYLIFE-II inertial fusion energy (IFE) power plant design have used simplistic assumptions in order to estimate radioactivity releases under accident conditions. Conservatisms associated with these traditional analyses can mask the actual behavior of the plant and have revealed the need for more accurate modeling and analysis of accident conditions and radioactivity mobilization mechanisms. In the present work a set of computer codes traditionally used for magnetic fusion safety analyses (CHEMCON, MELCOR) has been applied for simulating accident conditions in a simple model of the HYLIFE-II IFE design. Here the authors consider a severe lost of coolant accident (LOCA) producing simultaneous failures of the beam tubes (providing a pathway for radioactivity release from the vacuum vessel towards the containment) and of the two barriers surrounding the chamber (inner shielding and containment building it self). Even though containment failure would be a very unlikely event it would be needed in order to produce significant off-site doses. CHEMCON code allows calculation of long-term temperature transients in fusion reactor first wall, blanket, and shield structures resulting from decay heating. MELCOR is used to simulate a wide range of physical phenomena including thermal-hydraulics, heat transfer, aerosol physics and fusion product release and transport. The results of these calculations show that the estimated off-site dose is less than 6 mSv (0.6 rem), which is well below the value of 10 mSv (1 rem) given by the DOE Fusion Safety Standards for protection of the public from exposure to radiation during off-normal conditions.

  3. Fusion for Space Propulsion

    NASA Technical Reports Server (NTRS)

    Thio, Y. C. Francis; Schmidt, George R.; Santarius, John F.; Turchi, Peter J.; Siemon, Richard E.; Rodgers, Stephen L. (Technical Monitor)

    2002-01-01

    The need for fusion propulsion for interplanetary flights is discussed. For a propulsion system, there are three important system attributes: (1) The absolute amount of energy available, (2) the propellant exhaust velocity, and (3) the jet power per unit mass of the propulsion system (specific power). For efficient and affordable human exploration of the solar system, propellant exhaust velocity in excess of 100 km/s and specific power in excess of 10 kW/kg are required. Chemical combustion obviously cannot meet the requirement in propellant exhaust velocity. Nuclear fission processes typically result in producing energy in the form of heat that needs to be manipulated at temperatures limited by materials to about 2,800 K. Using the fission energy to heat a low atomic weight propellant produces propellant velocity of the order of 10 kinds. Alternatively the fission energy can be converted into electricity that is used to accelerate particles to high exhaust velocity. However, the necessary power conversion and conditioning equipment greatly increases the mass of the propulsion system. Fundamental considerations in waste heat rejection and power conditioning in a fission electric propulsion system place a limit on its jet specific power to the order of about 0.2 kW/kg. If fusion can be developed for propulsion, it appears to have the best of all worlds - it can provide the largest absolute amount of energy, the propellant exhaust velocity (> 100 km/s), and the high specific jet power (> 10 kW/kg). An intermediate step towards fusion propulsion might be a bimodal system in which a fission reactor is used to provide some of the energy to drive a fusion propulsion unit. There are similarities as well as differences between applying fusion to propulsion and to terrestrial electrical power generation. The similarities are the underlying plasma and fusion physics, the enabling component technologies, the computational and the diagnostics capabilities. These physics and

  4. Heat-pump cool storage in a clathrate of freon

    NASA Astrophysics Data System (ADS)

    Tomlinson, J. J.

    Presented are the analytical description and assessment of a unique heat pump/storage system in which the conventional evaporator of the vapor compression cycle is replaced by a highly efficient direct contract crystallizer. The thermal storage technique requires the formation of a refrigerant gas hydrate (a clathrate) and exploits an enthalpy of reaction comparable to the heat of fusion of ice. Additional system operational benefits include cool storage at the favorable temperatures of 4 to 7 C (40 to 45 F), and highly efficient heat transfer ates afforded by he direct contact mechanism. In addition, the experimental approach underway at ORNL to study such a system is discussed.

  5. Impact of Fast Ignition on Laser Fusion Energy Development

    NASA Astrophysics Data System (ADS)

    Mirna, Kunioki

    2016-10-01

    Reviewed are the early history of Japanese laser fusion research and the recent achievement of fast ignition research at Institute of Laser Engineering (ILE), Osaka University. After the achievement of high density compression at Osaka University, LLE of University Rochester, and LLNL, the critical issue of Inertial Fusion Energy (IFE) research became the formation of hot spark in a compressed plasma. In this lecture, the history of the fast ignition research will be reviewed and future prospects are presented.

  6. Survey of nuclear fusion technology. A prospect analysis of Tokamak fusion research

    NASA Astrophysics Data System (ADS)

    Hwang, W. K.

    The fusion research evaluation model for analyzing various R and D sinarios, the trend analysis of Tokamak research, and the near-term technologies are discussed. A computer code, FUSREV, was developed. It consists of the plasma power model and the cost/benefit model. Since the state-of-the-arts which are expected to be achieve as the result of subproject R and D's can only be obtained in the form of probability distribution functions Monte Carlo method is employed. The test computation of the code shows acceptable results. However, FUSREV was continuously modified employing new models for both technology and economics.

  7. Visualization of heat transport in heat pipes using thermocamera

    NASA Astrophysics Data System (ADS)

    Nemec, Patrik; Čaja, Alexander; Lenhard, Richard

    2010-10-01

    Heat pipes, as passive elements show a high level of reliability when taking heat away and they can take away heat flows having a significantly higher density than systems with forced convection. A heat pipe is a hermetically closed duct, filled with working fluid. Transport of heat in heat pipes is procured by the change of state of the working fluid from liquid state to steam and vice versa and depends on the hydrodynamic and heat processes in the pipe. This study have been focused on observing the impact these processes have on the heat process, the transport of heat within the heat pipe with the help of thermovision. The experiment is oriented at scanning the changes in the surface temperatures of the basic structural types of capillary heat pipes in vertical position.

  8. Fusion of neutron-rich oxygen isotopes in the crust of accreting neutron stars

    SciTech Connect

    Horowitz, C. J.; Dussan, H.; Berry, D. K.

    2008-04-15

    Fusion reactions in the crust of an accreting neutron star are an important source of heat, and the depth at which these reactions occur is important for determining the temperature profile of the star. Fusion reactions depend strongly on the nuclear charge Z. Nuclei with Z{<=}6 can fuse at low densities in a liquid ocean. However, nuclei with Z=8 or 10 may not burn until higher densities where the crust is solid and electron capture has made the nuclei neutron rich. We calculate the S factor for fusion reactions of neutron rich nuclei including {sup 24}O+{sup 24}O and {sup 28}Ne+{sup 28}Ne. We use a simple barrier penetration model. The S factor could be further enhanced by dynamical effects involving the neutron rich skin. This possible enhancement in S should be studied in the laboratory with neutron rich radioactive beams. We model the structure of the crust with molecular dynamics simulations. We find that the crust of accreting neutron stars may contain micro-crystals or regions of phase separation. Nevertheless, the screening factors that we determine for the enhancement of the rate of thermonuclear reactions are insensitive to these features. Finally, we calculate the rate of thermonuclear {sup 24}O+{sup 24}O fusion and find that {sup 24}O should burn at densities near 10{sup 11} g/cm{sup 3}. The energy released from this and similar reactions may be important for the temperature profile of the star.

  9. Coupling of transit time instabilities in electrostatic confinement fusion devices

    SciTech Connect

    Gruenwald, J. Fröhlich, M.

    2015-07-15

    A model of the behavior of transit time instabilities in an electrostatic confinement fusion reactor is presented in this letter. It is demonstrated that different modes are excited within the spherical cathode of a Farnsworth fusor. Each of these modes is dependent on the fusion products as well as the acceleration voltage applied between the two electrodes and they couple to a resulting oscillation showing non-linear beat phenomena. This type of instability is similar to the transit time instability of electrons between two resonant surfaces but the presence of ions and the occurring fusion reactions alter the physics of this instability considerably. The physics of this plasma instability is examined in detail for typical physical parameter ranges of electrostatic confinement fusion devices.

  10. Analytical and Experimental Investigations of Sodium Heat Pipes and Thermal Energy Storage Systems.

    DTIC Science & Technology

    1982-01-01

    evaporator length was 1.25 in. in length with the condenser 5 in. in length. The heat pipe wick consisted of a double wrap of 60 mesh nickel screen spot welded ...the heat pipes . Four Inconel sheathed Chromel-Alumel thermocouples were attached by resistance spot welding Inconel tabs to the heat pipe outside...accumulated. After this processing the heat pipes were closed using an electrode fusion weld to crimp and weld the filled tubes. The cleaning procedures

  11. Observation of Nuclear Fusion in Sonoluminescence

    SciTech Connect

    Taleyarkhan, Rusi

    2004-07-14

    The intense implosive collapse of bubbles, including acoustic cavitation bubbles, can lead to extremely high compressions and temperatures, and to the generation of light flashes attributed to sonoluminescence (SL). A novel technique was developed to induce ultra-high compressions and temperatures during SL events. Time spectra of neutron and SL emissions were measured in cavitation experiments with deuterated acetone. Statistically significant neutron and gamma ray emissions were measured with a calibrated liquid-scintillation detector along with SL emissions. The neutron and SL emissions were found to be time correlated over the time of significant bubble cluster dynamics. The neutron emission energy corresponded to < 2.45 MeV and had an emission rate of up to {approx}4-5 x 10{sup 5} n/s accompanied with gamma rays. Measurements of tritium production were also performed and these data implied a neutron emission rate due to D-D nuclear fusion which agreed with what was measured. In contrast, control experiments using normal acetone did not result in statistically significant tritium activity, or neutron or gamma ray emissions. The speaker will discuss experimental, modeling/simulation aspects along with remaining challenges and opportunities.

  12. Image fusion

    NASA Technical Reports Server (NTRS)

    Pavel, M.

    1993-01-01

    The topics covered include the following: a system overview of the basic components of a system designed to improve the ability of a pilot to fly through low-visibility conditions such as fog; the role of visual sciences; fusion issues; sensor characterization; sources of information; image processing; and image fusion.

  13. An Alternate View Of Munition Sensor Fusion

    NASA Astrophysics Data System (ADS)

    Mayersak, J. R.

    1988-08-01

    An alternate multimode sensor fusion scheme is treated. The concept is designed to acquire and engage high value relocatable targets in a lock-on-after-launch sequence. The approach uses statistical decision concepts to determine the authority to be assigned to each mode in the acquisition sequence voting and decision process. Statistical target classification and recognition in the engagement sequence is accomplished through variable length feature vectors set by adaptive logics. The approach uses multiple decision for acquisition and classification, in the number of spaces selected, is adaptively weighted and adjusted. The scheme uses type of climate -- arctic, temperate, desert, and equatorial -- diurnal effects --- time of day -- type of background, type of countermeasures present -- signature suppresssion or obscuration, false target decoy or electronic warfare -- and other factors to make these selections. The approach is discussed in simple terms. Voids and deficiencies in the statistical data base used to train such algorithms is discussed. The approach is being developed to engage deep battle targets such as surface-to-surface missile systems, air defense units and self-propelled artillery.

  14. Neutronics issues and inertial fusion energy: a summary of findings

    SciTech Connect

    Latkowski, J. F., LLNL

    1998-05-29

    We have analyzed and compared five major inertial fusion energy (IFE) and two representative magnetic fusion energy (MFE) power plant designs for their environment, safety, and health (ES&H) characteristics. Our work has focussed upon the neutronics of each of the designs and the resulting radiological hazard indices. The calculation of a consistent set of hazard indices allows comparisons to be made between the designs. Such comparisons enable identification of trends in fusion ES&H characteristics and may be used to increase the likelihood of fusion achieving its full potential with respect to ES&H characteristics. The present work summarizes our findings and conclusions. This work emphasizes the need for more research in low-activation materials and for the experimental measurement of radionuclide release fractions under accident conditions.

  15. On the Grothendieck rings of equivariant fusion categories

    SciTech Connect

    Burciu, Sebastian

    2015-07-15

    In this paper, we describe a Mackey type decomposition for group actions on abelian categories. This allows us to define new Mackey functors which associates to any subgroup the K-theory of the corresponding equivariantized abelian category. In the case of an action by tensor autoequivalences, the Mackey functor at the level of Grothendieck rings has a Green functor structure. As an application we give a description of the Grothendieck rings of equivariantized fusion categories under group actions by tensor autoequivalences on graded fusion categories. In this settings, a new formula for the tensor product of any two simple objects of an equivariantized fusion category is given, simplifying the fusion formula from Burciu and Natale [J. Math. Phys. 54, 013511 (2013)].

  16. The Gaussian curvature elastic energy of intermediates in membrane fusion.

    PubMed

    Siegel, David P

    2008-12-01

    The Gaussian curvature elastic energy contribution to the energy of membrane fusion intermediates has usually been neglected because the Gaussian curvature elastic modulus, kappa, was unknown. It is now possible to measure kappa for phospholipids that form bicontinuous inverted cubic (Q(II)) phases. Here, it is shown that one can estimate kappa for lipids that do not form Q(II) phases by studying the phase behavior of lipid mixtures. The method is used to estimate kappa for several lipid compositions in excess water. The values of kappa are used to compute the curvature elastic energies of stalks and catenoidal fusion pores according to recent models. The Gaussian curvature elastic contribution is positive and similar in magnitude to the bending energy contribution: it increases the total curvature energy of all the fusion intermediates by 100 units of k(B)T or more. It is important to note that this contribution makes the predicted intermediate energies compatible with observed lipid phase behavior in excess water. An order-of-magnitude fusion rate equation is used to estimate whether the predicted stalk energies are consistent with the observed rates of stalk-mediated processes in pure lipid systems. The current theory predicts a stalk energy that is slightly too large, by approximately 30 k(B)T, to rationalize the observed rates of stalk-mediated processes in phosphatidylethanolamine or N-monomethylated dioleoylphosphatidylethanolamine systems. Despite this discrepancy, the results show that models of fusion intermediate energy are accurate enough to make semiquantitative predictions about how proteins mediate biomembrane fusion. The same rate model shows that for proteins to drive biomembrane fusion at observed rates, they have to perform mediating functions corresponding to a reduction in the energy of a purely lipidic stalk by several tens of k(B)T. By binding particular peptide sequences to the monolayer surface, proteins could lower fusion intermediate

  17. Studies of electron and proton isochoric heating for fast ignition

    SciTech Connect

    Mackinnon, A; Key, M; Akli, K; Beg, F; Clarke, R; Clarke, D; Chen, M; Chung, H; Chen, S; Freeman, R; Green, J; Gu, P; Gregori, G; Highbarger, K; Habara, H; Hatchett, S; Hey, D; Heathcote, R; Hill, J; King, J; Kodama, R; Koch, J; Lancaster, K; Langdon, B; Murphy, C; Norreys, P; Neely, D; Nakatsutsumi, M; Nakamura, H; Patel, N; Patel, P; Pasley, J; Snavley, R; Stephens, R; Stoeckl, C; Foord, M; Tabak, M; Theobald, W; Storm, M; Tanaka, K; Tempo, M; Toley, M; Town, R; Wilks, S; VanWoerkom, L; Weber, R; Yabuuchi, T; Zhang, B

    2006-10-02

    Isochoric heating of inertially confined fusion plasmas by laser driven MeV electrons or protons is an area of great topical interest in the inertial confinement fusion community, particularly with respect to the fast ignition (FI) proposal to use this technique to initiate burn in a fusion capsule. Experiments designed to investigate electron isochoric heating have measured heating in two limiting cases of interest to fast ignition, small planar foils and hollow cones. Data from Cu K{alpha} fluorescence, crystal x-ray spectroscopy of Cu K shell emission, and XUV imaging at 68eV and 256 eV are used to test PIC and Hybrid PIC modeling of the interaction. Isochoric heating by focused proton beams generated at the concave inside surface of a hemi-shell and from a sub hemi-shell inside a cone have been studied with the same diagnostic methods plus imaging of proton induced K{alpha}. Conversion efficiency to protons has also been measured and modeled. Conclusions from the proton and electron heating experiments will be presented. Recent advances in modeling electron transport and innovative target designs for reducing igniter energy and increasing gain curves will also be discussed.

  18. The National Network of Fusion Centers: Perception and Reality

    DTIC Science & Technology

    2014-12-01

    NETWORK OF FUSION CENTERS: PERCEPTION AND REALITY by Nicholas Klem December 2014 Thesis Co-Advisors: Lauren Wollman Patrick Miller THIS...Thesis 4. TITLE AND SUBTITLE THE NATIONAL NETWORK OF FUSION CENTERS: PERCEPTION AND REALITY 6. AUTHOR(S) Nicholas Klem 7. PERFORMING...held of the Netv.•ork appear at times to be based on perceptions incongment with some of the realities of cw1·ent Network operations and which lead

  19. Fusion Cross Sections of Astrophysics Interest Within the STELLA Project

    NASA Astrophysics Data System (ADS)

    Courtin, Sandrine; Fruet, Guillaume; Jenkins, David G.; Heine, Marcel; Montanari, Daniele; Morris, Luke G.; Lotay, Gavin; Regan, Patrick H.; Kirsebom, Oliver S.; Della Negra, Serge; Hammache, Faïrouz; de Sereville, Nicolas; Bastin, Beyhan; de Oliveira, François; Randisi, Giacomo; Stodel, Christelle; Beck, Christian; Haas, Florent

    Low energy fusion between light heavy-ions is a key feature of the evolution of massive stars. In systems of astrophysical interest, the process may be strongly affected by molecular configurations of the compound nucleus, leading to resonant S factors. In particular, the 12C+12C fusion reaction has been the object of numerous experimental investigations. The STELLA project has been developed to extend these investigations to lower energies towards the Gamow window.

  20. Fusion of {sup 9}Li with {sup 208}Pb

    SciTech Connect

    Vinodkumar, A. M.; Loveland, W.; Sprunger, P. H.; Prisbrey, L.; Trinczek, M.; Dombsky, M.; Machule, P.; Kolata, J. J.; Roberts, A.

    2009-11-15

    We have measured the fusion excitation function for the {sup 9}Li+{sup 208}Pb reaction for near-barrier projectile center-of-mass energies of 23.9 to 43.0 MeV using the ISAC2 facility at TRIUMF. The {alpha}-emitting evaporation residues ({sup 211-214}At) were stopped in the {sup 208}Pb target, and their decay was measured. The isotopic yields at each energy were in good agreement with the predictions of a statistical model code (HIVAP). The measured fusion excitation function shows evidence for substantial sub-barrier fusion enhancement not predicted by current theoretical models. There is a suppression of the above barrier cross sections relative to these model predictions. The implications of this measurement for studying the fusion of {sup 11}Li with {sup 208}Pb are discussed.

  1. Properties of ecosystems that are vulnerable during eco-fusion

    PubMed Central

    Yoshida, Katsuhiko; Tokita, Kei

    2015-01-01

    When two ecosystems with separate evolutionary histories come into contact (eco-fusion), reciprocal invasions occur during their fusion. Asymmetries in the migration direction or extinction rate then occur (e.g., during the Great American Biotic Interchange, GABI). Hypotheses have been proposed to describe this process, but the ecosystem properties have not been adequately discussed. To identify the ecosystem properties that create vulnerability to species loss during eco-fusion, we conducted computer simulations of the fusion of ecosystems with independent evolutionary histories. With asymmetrical species extinction rates, the ecosystem with a higher extinction rate had a shorter food chain, a higher ratio of animal species to plant species, and a lower ratio of carnivores to herbivores. Most ecosystems that have undergone isolated evolution are vulnerable. These results may explain the vulnerability of South America's ecosystem during the GABI and that of modern Australia. PMID:25631294

  2. Properties of ecosystems that are vulnerable during eco-fusion.

    PubMed

    Yoshida, Katsuhiko; Tokita, Kei

    2015-01-29

    When two ecosystems with separate evolutionary histories come into contact (eco-fusion), reciprocal invasions occur during their fusion. Asymmetries in the migration direction or extinction rate then occur (e.g., during the Great American Biotic Interchange, GABI). Hypotheses have been proposed to describe this process, but the ecosystem properties have not been adequately discussed. To identify the ecosystem properties that create vulnerability to species loss during eco-fusion, we conducted computer simulations of the fusion of ecosystems with independent evolutionary histories. With asymmetrical species extinction rates, the ecosystem with a higher extinction rate had a shorter food chain, a higher ratio of animal species to plant species, and a lower ratio of carnivores to herbivores. Most ecosystems that have undergone isolated evolution are vulnerable. These results may explain the vulnerability of South America's ecosystem during the GABI and that of modern Australia.

  3. [Pathophysiology of heat illness].

    PubMed

    Aruga, Tohru; Miyake, Yasufumi

    2012-06-01

    Human core temperature is strictly controlled by mechanism of radiation, conduction, convection, and evaporation from skin surface. Serial hot and humid climate induces dehydration which interferes heat pump-out from the body. Heart dysfunction is the third factor to rise body temperature. Hyperthermia and hypo-perfusion caused by dehydration and heart failure deteriorate specific organ functions, i.e. central nervous system, liver and renal functions and coagulation system. Disseminated intravascular coagulopathy is one of the standard indicators of severity and mortality of heat stroke.

  4. Tidal heating of Ariel

    NASA Astrophysics Data System (ADS)

    Tittemore, William C.

    1990-09-01

    During evolution through the 4:1 commensurability early in the history of the Uranian system, over 3.8 billion years ago, tidal heating may have raised the internal temperature of Ariel by up to about 20 K; the internal temperature of Ariel may already have been high in virtue of both accretional and radiogenic heating. The additional increase in Ariel's temperature could then have triggered the geological activity that led to a late resurfacing, by decreasing lithospheric thickness and exacerbating thermal stresses on it to the point where observed cracks and faults formed.

  5. Tidal heating of Ariel

    NASA Technical Reports Server (NTRS)

    Tittemore, William C.

    1990-01-01

    During evolution through the 4:1 commensurability early in the history of the Uranian system, over 3.8 billion years ago, tidal heating may have raised the internal temperature of Ariel by up to about 20 K; the internal temperature of Ariel may already have been high in virtue of both accretional and radiogenic heating. The additional increase in Ariel's temperature could then have triggered the geological activity that led to a late resurfacing, by decreasing lithospheric thickness and exacerbating thermal stresses on it to the point where observed cracks and faults formed.

  6. Role of the synaptobrevin C terminus in fusion pore formation

    PubMed Central

    Ngatchou, Annita N.; Kisler, Kassandra; Fang, Qinghua; Walter, Alexander M.; Zhao, Ying; Bru