Energy Technology Data Exchange (ETDEWEB)

A generic reactor model is used to examine the economic viability of electricity generation by magnetic fusion. The simple model uses components which are representative of those used in previous reactor studies of deuterium-tritium burning tokamaks, stellarators, bumpy tori, reverse field pinches and tandem mirrors. Conservative costing assumptions are made. The generic reactor is not a tokamak but rather it is intended to emphasize what is common to all magnetic fusion reactors. The reactor uses a superconducting toroidal coil set to produce the dominant magnetic field. To this extent it is a less good approximation to systems, such as the reversed field pinch in which the main field is produced by a plasma current. The main output of the study is the cost of electricity as a function of the weight and size of the ...

International Nuclear Information System (INIS)

High power and particle deposition on target materials are encountered in many applications including magnetic and inertial fusion devices, nuclear and high energy physics applications, and laser and discharge produced plasma devices. Surface and structural damage to plasma-facing components due to the frequent loss of plasma confinement remains a serious problem for the Tokamak reactor concept. The deposited plasma energy causes significant surface erosion, possible structural failure, and frequent plasma contamination.

International Nuclear Information System (INIS)

... S. Perfilov, SV Institute of Nuclear Fusion, RRC Kurchatov Institute, Moscow

Energy Technology Data Exchange (ETDEWEB)

Brookhaven National Laboratory is involved in a conceptual design study of a commercial nuclear power system which utilizes high-temperature electrolysis to produce synthetic fuels. The system is called HYFIRE. It includes a tokamak fusion power reactor supplying electrical and thermal energy to an array of electrolytes. The electrolytes produce hydrogen which can be used either directly as a fuel or in the production of hydrocarbons. The purpose of the study is to provide a mechanism for DOE to further assess the commercial potential of fusion using a tokamak reactor to produce synthetic fuel. The HYFIRE design is based on the tokamak commercial power reactor, STARFIRE. STARFIRE uses the deuterium/tritium/lithium fuel cycle. The HYFIRE study assumes the plasma shape and characteristics of STARFIRE study but uses a different blanket design. This study is particularly interested in ...

Energy Technology Data Exchange (ETDEWEB)

A tutorial account is given of the main characteristics and distinctive features of conceptual magnetic fusion systems employing the magnetic mirror principle. These features are related to the potential advantages that mirror-based fusion systems may exhibit for the generation of economic fusion power.

Energy Technology Data Exchange (ETDEWEB)

The prospects for the low-aspect-ratio (A) tokamak to fulfill the requirements of viable fusion power plants are considered relative to the present status in data and modeling. Desirable physics and design features for an attractive Blanket Test Facility and power reactors are estimated for low-A tokamaks based on calculations improved with the latest data from small pioneering experiments. While these experiments have confirmed some of the recent predictions for low-A, they also identify the remaining issues that require verification before reliable projections can be made for these deuterium-tritium applications. The results show that the low-A regime of small size, modest field, and high current offers a path complementary to the standard and high A tokamaks in developing the full potential of fusion power.

Energy Technology Data Exchange (ETDEWEB)

Pfirsch-Schlueter (P-S) current is an inherent property of a finite pressure toroidal equilibrium of tokamak and stellarator. However, it was pointed out recently (V.D. Pustovitov, Nuclear Fusion 36 (1996) 583) that the P-S current would be suppressed completely if the external vertical field could be adjusted to satisfy the condition {omega}=<{omega}> in an l=3 stellarator. Here {omega}=<B tilde{sup 2}>/B{sub 0}{sup 2}-2{epsilon} cos{theta}, l is a pole number, |B tilde| the vacuum helical magnetic field, B{sub 0} the toroidal field, {epsilon} the inverse aspect ratio, {theta} the poloidal angle and <...> denotes the average over the toroidal angle. An example of such a stellarator equilibrium is presented in this paper. For this stellarator equilibrium, behavior of rotational transform and Boozer magnetic spectrum is clarified when the pressure is increased. ...

Energy Technology Data Exchange (ETDEWEB)

This report continues the studies of simplified methods, of magnetic diagnostics in application to TCA/BR tokamak. Here we study the accuracy of known formula for {beta}{sub 1} + l{sub 1}/2 determination from the poloidal magnetic field asymmetry. Errors of the diamagnetic measurements due to vibrations of the vacuum vessel are also considered. (author). 3 refs., 1 fig., 1 tab.

International Nuclear Information System (INIS)

''Magnetic braking'' of the plasma toroidal rotation in the high confinement H mode by applied resonant, low m,n=1 static error fields is used in DIII-D [Nucl. Fusion 31, 875 (1991)] as an independent control to evaluate the E_rxB stabilization of microturbulence in the plasma core. In the core (#rho# approx-lt 0.9) of a tokamak, the radial electric field and its shear are dominated by toroidal rotation. The fundamental quantity for shear stabilization of microturbulence is shear in the velocity of the fluctuations v_p_e_r_p_e_n_d_i_c_u_l_a_r#approx#E_rxB/B#centre dot#B which in the core is v_p_e_r_p_e_n_d_i_c_u_l_a_r#approx#v_#phi#B_#theta#/ B_#phi#. With magnetic braking greatly decreasing the toroidal rotation and thus reducing the core radial electric field and shear, far infrared (FIR) measurements of density microturbulence show downshifting in frequency near #rho##approx#0.8 as a result of the ...

Science.gov (United States)

... in the design of such devices as fusion reactors, magnetohydrodynamic generators, magnetically levitated vehicles, magnetic forming devices, and ...

Energy Technology Data Exchange (ETDEWEB)

The calculated radioactive waste inventories of the Turkey Point pressurized water fission reactor (PWR) and the Starfire conceptual fusion tokamak are compared as a function of time from initial start-up to 10,000 years after decommissioning. Only material out of reactor at least one year is considered. The total activity in Ci/W(th) of the Starfire tokamak is slightly greater than that of the PWR during the active lifetimes of the two reactors and beyond 1000 years. However, using reduced activation materials in Starfire can result in about 1/2000 as much long-lived radioactivity as in the fission reactor. It is stressed that comparison of wastes on this basis is not straightforward, since the radioisotopes and methods required for their disposal are different for fusion and fission reactors. 2 refs., 1 fig., 2 tabs.

Energy Technology Data Exchange (ETDEWEB)

The activation aspects of pure fusion and hybrid fusion technology is studied to assess the radioactive safety of various fusion concepts including tokamak pure fusion, fissile fuel producing hybrid and radio waste transmuting hybrid. The activation properties of breeding, coolant and structural materials in fusion reactors might be quite different from those in fission reactors because of the high energy D-T fusion neutrons from the fusion cores. A study on the involved activation reactions and the uncertainties of the associated nuclear cross-sections is carried. The activation properties of various first wall concepts and blanket concepts are discussed. The radioactive inventory during the operation lifetime and the potential hazard of the radioactive nuclides with respect to near term (reprocessing) and long term ...

Energy Technology Data Exchange (ETDEWEB)

Power loadings experienced by tokamak plasma-facing components during normal operation and during off-normal events are discussed. A model for power and particle flow in the tokamak boundary layer is presented and model predictions are compared to infrared measurements of component heating. The inclusion of the full three-dimensional geometry of the components and of the magnetic flux surface is very important in the modeling. Experimental measurements show that misalignment of component armour tile surfaces by only a millimeter can lead to significant localized heating. An application to the design of plasma-facing components for future machines is presented. Finally, thermal loads expected during tokamak disruptions are discussed. The primary problems are surface melting and vaporization due to localized intense heating during the disruption thermal quench and volumetric heating of the component ...

International Nuclear Information System (INIS)

Contrary to previous plans for the preparation of diagnostic systems for D-T break-even experiments in the Tokamak Fusion Test Reactor (TFTR), it now appears that a limited Q#approx#1 demonstration can be carried out without constructing a close-fitting igloo radiation shield around the tokamak. In order to assess the impact of D-T operation of TFTR without an igloo shield, particularly with regard to hardening of diagonstic systems, we have mapped neutron and gamma fluxes inside the test cell and test cell basement, using a variety of radiation measurements. The measurements are sufficiently detailed to resolve massive hardware components, such as neutral beams and shielded diagnostic systems, and can be used to predict local fluxes. By comparing the measurements with transport code calculations for the case of a bare tokamak, we conclude that the models have substantially overestimated fluxes both ...

International Nuclear Information System (INIS)

Afterheat represents an important consideration in design of conceptual fusion power reactors, particularly during normal or unplanned shutdown. Afterheat calculations have been undertaken for various generic designs, but with special reference to the Culham DEMO reactor. These calculations have included the redistribution of heating by gamma ray transport. Selected temperature response calculations have been undertaken. (author).

International Nuclear Information System (INIS)

The Fusion Technology task performs analyses and systems studies of conceptual fusion reactors based upon inertial and high-#beta# magnetic confinement schemes. Progress in the areas of theoretical analysis (plasma and neutral-gas blanket models), specific reactor studies (toroidal and linear theta pinches, Z pinches, laser fusion) neutronic and nuclear data assessments, materials (metals and insulators) evaluation, and general engineering design is reported.

Energy Technology Data Exchange (ETDEWEB)

The heating and current drive systems are being developed to support long pulse, high {beta}, advanced tokamak fusion physics experiments in the KSTAR tokamak. The heating and current drive systems consisting of neutral beam injection (NBI), ion cyclotron waves (ICRF), lower hybrid waves (LHCD) and electron cyclotron waves (ECH/ECCD) have been designed to operate for pulse lengths up to 300 sec and to provide a range of control functions including current drive and profile control. Development of key technologies for high power, long pulse operation has been on going. Substantial progress has been made on areas such as RF launchers, ion source, and high power supplies.

Energy Technology Data Exchange (ETDEWEB)

A new, magnetically insulated negative ion source has recently been discovered which can produce pulsed negative ion beams (H/sup -/, Li/sup -/, and C/sup -/) with intensities of 100-300 A/cm/sup 2/ at 1-4 MeV. This source may provide the basis for a high energy neutral beam system for heating large tokamaks.

Energy Technology Data Exchange (ETDEWEB)

The use of deuterium-tritium fuel in the Compact Ignition Tokamak will require applying remote handling technology for ex-vessel maintenance and replacement of machine components. Highly activated and contaminated components of the fusion devices auxiliary systems, such as diagnostics and RF heating, must be replaced using remotely operated maintenance equipment in the test cell. In-vessel remote maintenance included replacement of divertor and first wall hardware, faraday shields, and for an in-vessel inspection system. Provision for remote replacement of a vacuum vessel sector, toroidal field coil or poloidal field ring coil was not included in the project baseline. As a result of recent coil failures experienced at a number of facilities, the CIT project decided to reconsider the question of remote recovery from a coil failure and, in January of 1990, initiated a coil replacement study. This study focused on the technical requirements and ...

Energy Technology Data Exchange (ETDEWEB)

A low power polychromatic beam of microwaves is used to diagnose the behavior of turbulent fluctuations in the core of the JT-60U tokamak during the evolution of the internal transport barrier. A continuous reduction in the size of turbulent structures is observed concomitant with the reduction of the density scale length during the evolution of the internal transport barrier. The density correlation length decreases to the order of the ion gyroradius, in contrast to the much longer scale lengths observed earlier in the discharge, while the density fluctuation level remain similar to the level before transport barrier formation.

Energy Technology Data Exchange (ETDEWEB)

Concept Exploration (CE) experiments within the Innovative Confinement Concept Program have a unique role which impacts their contributions to the development of fusion energy. As stated in the FESAC ''Report on Alternate Concepts:'' These [CE] programs are aimed at innovation and basic understanding of relevant scientific phenomena. The emphasis on innovation motivates their application to the search for a better fusion reactor configuration. In addition, because of their unique character the CE experiments offer excellent opportunities to couple fusion-plasma physics to other sciences. A recent example of coupling is the fusion self-organized plasmas to reconnection physics and extra-terrestrial plasmas. Perhaps of even greater importance is the education of the future scientists needed for developing fusion energy. The CE experiments, both at ...

International Nuclear Information System (INIS)

The cross section database for electron impact excitation and electron impact ionization for hydrogen beam kinetic energies greater than 100 eV was considered, giving for each particular process a reference to a recommended publication of cross sections, as well as the accuracy or estimated accuracy. The work is motivated by the application of neutral beam injection in magnetic confinement devices, such as large tokamaks. 9 refs, 2 figs.

Energy Technology Data Exchange (ETDEWEB)

The paper describes a concept of extracting fusion power from D-{sup 3}He fueled IEC (Inertia Electrostatic Configuration) devices. The fusion system consists of a series of fusion modules and direct energy converters at an end or at both ends. This system of multiple units is linear and is connected by a magnetic field. A pair of coils anti-parallel to the magnetic field yields a field-null domain at the center of each unit as required for IEC operation. A stabilizing coil installed between the coil pairs eliminates the strong attractive force between the anti-parallel coils. Accessible regions for charged particle trajectories are essentially isolated from the coil structure. Thus, charged particles are directed along magnetic field lines to the direct energy converter without appreciable losses. A direct energy converter unit designed to be compatible to this ...

International Nuclear Information System (INIS)

The existing Tokamak Fusion Test Reactor Neutral Beam system is proposed to be modified for long pulse operation on the Tokamak Physics Experiment (TPX). Day one of TPX will call for one TFTR beamline modified for 1000 second pulse lengths oriented co-directional to the plasma current. The system design will be capable of accommodating an additional co-directional and a single counter directional beamline. For the TPX conceptual design, every attempt was made to use existing Neutral Beam hardware, plant facilities, auxiliary systems, service infrastructure, and control systems. This paper describes the moderate modifications required to the power systems, the ion sources, and the beam impinged surfaces of the ion dumps, the calorimeters, the various beam scrapers, and the neutralizers. Also described are the minimal modifications required to the vacuum, cryogenic, and gas systems and the major modification of replacing the ...

Energy Technology Data Exchange (ETDEWEB)

Solenoid transport of high current, heavy ion beams is considered for several stages of a heavy ion fusion driver. In general this option is more efficient than magnetic quadrupole transport at sufficiently low kinetic energy and/or large e/m, and for this reason it has been employed in electron induction linacs. Ideally an ion beam would be transported in a state of Brillouin flow, i.e. cold in the transverse plane and spinning at one half the cyclotron frequency. The design of appropriate solenoids and the equilibrium and stability of transported ion beams are discussed. An outline of application to a fusion driver is also presented.

Science.gov (United States)

Environmental characteristics of conceptual fusion-reactor systems based on magnetic confinement are examined quantitatively, and some comparisons with fission systems are made. Fusion, like all other energy sources, will not be completely free of environmental liabilities, but the most obvious of these-- tritium leakage and activation of structural materials by neutron bombardment-- are susceptible to significant reduction by ingenuity in choice of materials and design. Large fusion reactors can probably be designed so that worst-case releases of radioactivity owing to accident or sabotage would produce no prompt fatalities in the public. A world energy economy relying heavily on fusion could make heavy demands on scarce nonfuel materials, a topic deserving further attention. Fusion's potential environmental advantages are not ...

International Nuclear Information System (INIS)

Field reversed configuration (FRC) is a prospective high ? magnetic system for high efficiency D- 3He fusion reactor. Self-consistent FRC plasma profiles and static electric field for reactor calculations are discussed in framework of the model including flow equilibrium and collisionless transport equations. The extrapolations to reactor regimes of plasma confinement scaling laws are considered.

Science.gov (United States)

Mar 1, 2011 ... DIES (2) [x] : WELDING (2) [x] : GAS PRESSURE (2) [x] : WELD STRENGTH (2) [x] : MAGNETIC FORMING (2) [x] : FUSION WELDING (2) [x] ...

Energy Technology Data Exchange (ETDEWEB)

This report reviews Soviet R and D of (1) high-intensity negative ion sources and (2) transport and focusing of negative ion beams, using Soviet open literature of the past ten years, and correlates this data with data on Soviet institutes responsible for negative ion beam development. The Soviets are developing intense negative ion beams as the basis for creating neutral beams for injection into mirror traps and tokamaks, for inertial confinement fusion, and possibly for exoatmospheric beam weapon applications. The report focuses specifically on surface-plasma-type ion sources, which were first developed in the USSR and which show great promise for creating beams of high intensity, high brightness, and low emittance. Mechanisms for optimum negative ion beam transport are also discussed.

Energy Technology Data Exchange (ETDEWEB)

Linear properties of ion temperature gradient (ITG) modes in helical systems are studied. The real frequency, growth rate, and eigenfunction are obtained for both stable and unstable cases by solving a kinetic integral equation with proper analytic continuation performed in the complex frequency plane. Based on the model magnetic configuration for toroidal helical systems like the Large Helical Device (LHD), dependences of the ITG mode properties on various plasma equilibrium parameters are investigated. Particularly, relative effects of {nabla}B-curvature drifts driven by the toroidicity and by the helical ripples are examined in order to compare the ITG modes in helical systems with those in tokamaks. (author)

Energy Technology Data Exchange (ETDEWEB)

Taking the development of large current, negative ion sources which is in progress aiming at nuclear fusion reactors and the development of high luminance ion sources planned as a part of the Omega Project as the examples, the technology for generating high power ion beams is explained. Both these projects are positioned at the limit of the present technology of high power ion beam application as their targeted beam power reaches several tens MW. Consequently, the requirement for the ion sources is severe, and in particular, the generation of the ion beams having large current density with good convergence is beyond all precedents. The application of high power ion sources has been realized as the neutral beam injectors for large tokamaks. Also the hydrogen negative ion source of large current and the electrostatic acceleration technology for negative ion beams have been developed. Large plasma sources, the method of generating negative ions ...

Energy Technology Data Exchange (ETDEWEB)

The electron cyclotron resonance layer in a tokamak, {omega}={omega}{sub c}(r), is not accessible by the extraordinary wave from the low field side, because it is shielded by a cutoff layer. However, a X-mode launched with a nonzero toroidal angle propagates at the cutoff parallel to the magnetic field and has a circular polarization. Therefore it can already at the cutoff layer interact efficiency with electrons via the Doppler shifted resonance. The driven current can be substantially higher than that driven by the second harmonic X-mode. The applicability of this current drive scheme is limited to rather low values of {omega}{sub p}{sup 2}/{omega}{sub c}{sup 2}, but may be of interest for high magnetic field devices. (author)

International Nuclear Information System (INIS)

During the operation of a tokamak, the first wall elements suffer very high heat fluxes. Heat is removed by internal cooling by means of water, helium or fluid metal. The resulting inhomogeneous temperature field cause internal stresses which, due to the pulsed operation are of cyclic nature. Additional mechanical stresses in the first wall may be caused by disruptions or vertical plasma movements. During theses events high currents are induced in the metallic part of the first wall which by their interaction with the magnetic field of the tokamak lead to mechanical forces. These electromechanical stresses may lie beyond the yield stress of the structural material. From the interaction of thermal and mechanical forces, a complex stress state is achieved which under certain circumstances may lead to premature failure and/or to progressive plastic deformations (ratcheting). In order to study the boundary conditions for the ...

Energy Technology Data Exchange (ETDEWEB)

The economic prospects for magnetic fusion energy can be dramatically improved if for the same total power output the fusion neutron first-wall (FW) loading and the system power density can be increased by factors of 3 to 5 and 10 to 30, respectively. A number of compact fusion reactor embodiments have been proposed, all of which would operate with increased FW loadings, would use thin (0.5 to 0.6 m) blankets, and would confine quasi-steady-state plasma with resistive, water-cooled copper or aluminum coils. Increased system power density (5 to 15 MWt/m/sup 3/ versus 0.3 to 0.5 MW/m/sup 3/), considerably reduced physical size of the fusion power core (FPC), and appreciably reduced economic leverage exerted by the FPC and associated physics result. The unique materials requirements anticipated for these compact reactors are outlined against the well documented backdrop provided by ...

Energy Technology Data Exchange (ETDEWEB)

The most striking achievement in magnetic fusion experiments during last few years was the discovery of plasma detachment from material targets, a much needed effect for plasmas with high power fusion parameters. Due to the very low heat loads on the targets observed in these regimes and potentially low erosion of the targets, detached regimes look attractive from the International Thermonuclear Experimental Reactor (ITER) design point of view. Thus the author has experimental proof for the possibility for a co-existence of fusion relevant hot plasma in the core and a low temperature partly ionized plasma at the edge of magnetic fusion device. Although somewhat similar behavior of edge plasma was considered theoretically even before plasma detachment was found experimentally, it was not clear in the beginning how these theoretical and experimental findings would ...

International Nuclear Information System (INIS)

A strong toroidal rotation braking has been observed in plasmas with application of an n = 1 magnetic perturbation field on the JET tokamak. Calculation results from the momentum transport analysis show that the torque induced by the n = 1 perturbation field has a global profile. The maximal value of this torque is at the plasma core region (#rho# < 0.4) and it is about half of the neutral beam injection torque. The calculation shows that the plasma is mainly in the #nu#_-#sq root##nu# regime in the plasma core, but it is close to the transition between the 1/#nu# and #nu#_-#sq root##nu# regimes. The neoclassical toroidal viscosity (NTV) torque in the 1/#nu# and #nu#_-#sq root##nu# regimes is calculated. The observed torque is of a magnitude in between that of the NTV torque in the 1/#nu# and #nu#_-#sq root##nu# regimes. The NTV torque in the #nu#_-#sq root##nu# regimes is enhanced using the Lagrangian variation of the ...

International Nuclear Information System (INIS)

ARIES-AT is a 1000 MWe conceptual fusion power plant design with a very low projected cost of electricity. The design contains many innovative features to improve both the physics and engineering performance of the system. From the safety and environmental perspective, there is greater depth to the overall analysis than in past ARIES studies. For ARIES-AT, the overall spectrum of off-normal events to be examined has been broadened. They include conventional loss of coolant and loss of flow events, an ex-vessel loss of coolant, and in-vessel off-normal events that mobilize in-vessel inventories (e.g., tritium and tokamak dust) and bypass primary confinement such as a loss of vacuum and an in-vessel loss of coolant with bypass. This broader examination of accidents improves the robustness of the design from the safety perspective and gives additional confidence that the facility can meet the no-evacuation requirement under average weather ...

Energy Technology Data Exchange (ETDEWEB)

Liquid metal cooling for the first wall and blanket of a magnetic confinement fusion reactor has various advantages. However, it has the disadvantages of large magnetohydrodynamic pressure drops and heat transfer deterioration under a strong magnetic field. Thus, the present authors have proposed cooling with a helium-lithium annular mist flow as well as the cooling with a liquid metal boiling flow, and as fundamental studies, investigated the effect of a magnetic field on the flow characteristics and heat transfer of liquid metal two-phase systems since the 1970s. In the present paper we summarize the important findings obtained from our experimental studies for (i) an air-mercury stratified flow in a horizontal rectangular channel, (ii) a helium-lithium annular mist flow in a horizontal rectangular channel, (iii) the mercury pool boiling on a horizontal surface, and (iv) air-mercury upward flows in a ...

Energy Technology Data Exchange (ETDEWEB)

Modern imaging technologies visualize different aspects of disease in a non-invasive way. Considerable progress has been made in the fusion of images from different imaging modalities using software approaches. One goal of fusion software is to align anatomical and functional images and allow improved spatial localization of abnormalities. The resulting correlation of the anatomical and functional images may clarify the nature of the abnormality and help diagnose or stage the underlying disease. Whereas successful image fusion software has been developed for the brain, only limited success has been achieved for image alignment in other parts of the body. The development and current status of alternative approaches are presented. Dual-modality imaging is described with devices where two modalities are combined and mounted in a single gantry. The use of existing scanner technology ensures that no compromises are made in the ...

Energy Technology Data Exchange (ETDEWEB)

Neutral beam systems for the next generation of magnetic fusion devices will be based on negative ions. Developments are progressing steadily, and large negative ion-based systems are under preparation for JT60-U and LHD, and are being considered for ITER. An overview of the physics of the production, acceleration and neutralization of large negative ion beams is given. The present state of the art in R and D is also surveyed. (Author).

International Nuclear Information System (INIS)

The most important results of theoretical and experimental studies of plasmas, which have been achieved at the IPJ in Swierk and IPPLM in Warsaw recently, are presented. Studies of physical phenomena in PF discharges, development of diagnostic techniques and research on new plasma technologies, as performed at IPJ, have been summarized. Studies of dense magnetized plasmas, investigation of physics and applications of laser-produced plasmas; and research on the development of advanced diagnostic techniques for the EUROATOM fusion program, as performed at IPPLM, are also described.

International Nuclear Information System (INIS)

The importance of neutron measurements both as a succinct measure of the progress to fusion ignition using the magnetic confinement route and also as a diagnostic of plasma conditions is discussed. The various neutron diagnostic systems that have been or are being constructed by AERE Harwell for JET are described. The properties to be measured by such diagnostics are clearly identified and some results obtained with the installed diagnostics during d-d plasmas are presented.

CERN Document Server

The term ``dynamo'' means different things to the laboratory fusion plasma and astrophysical plasma communities. To alleviate the resulting confusion and to facilitate interdisciplinary progress, we pinpoint conceptual differences and similarities between laboratory plasma dynamos and astrophysical dynamos. We can divide dynamos into three types: 1. magnetically dominated helical dynamos which sustain a large scale magnetic field against resistive decay and drive the magnetic geometry toward the lowest energy state, 2. flow-driven helical dynamos which amplify or sustain large scale magnetic fields in an otherwise turbulent flow, and 3. flow-driven nonhelical dynamos which amplify fields on scales at or below the driving turbulence. We discuss how all three types occur in astrophysics whereas plasma confinement device dynamos are of the first type. Type 3 dynamos requires no ...

International Nuclear Information System (INIS)

In this article are presented main results on electric potential investigations in stellarator/torsatron TJ-II and tokamak T-10 in a comparable regimes of device operation.

Science.gov (United States)

Recent experiments with TFTR, D-III-D and JET involving the injection and trapping of low density beams of high energy large orbit ions indicate that large orbit non-adiabatic ions slow down and diffuse classically in the presence of anomalous fluctuations and transport of adiabatic majority particles. Accordingly, we consider conceptual fusion reactors(N. Rostoker, M.W. Binderbauer and H.J. Monkhorst, Science) 278, 1419 (1997). based on classical confinement of fuel ions and fusion products(M.W. Binderbauer and N. Rostoker, J. Plasma Phys.) 56, 451 (1996).. The magnetic confinement geometry of the proposed designs is a Field Reversed Configuration. A survey of experimental results on instabilities and their characteristics as related to these reactor concepts is presented. Particular focus will be given to long wavelength (as compared to gyro-radius) and low frequency (?<< c/r_o, r_o=3D major radius of annular ...

International Nuclear Information System (INIS)

... edge localized modes h-mode plasma confinement jet tokamak l-mode plasma

Energy Technology Data Exchange (ETDEWEB)

Pellet injectors are needed to fuel long pulse tokamak plasmas and other magnetic confinement devices. For this purpose, an apparatus has been developed that forms 1.3-mm-diam pellets of frozen deuterium at a rate of 40 pellets per second and accelerates them to a speed of 1 km/s. Pellets are formed by extruding a billet of solidified deuterium through a 1.3-mm-diam nozzle at a speed of 5 cm/s. The extruding deuterium is chopped with a razor knife, forming 1.3-mm right circular cylinders of solid deuterium. The pellets are accelerated by synchronously injecting them into a high speed rotating arbor containing a guide track, which carries them from a point near the center of rotation to the periphery. The pellets leave the wheel after 150/sup 0/ of rotation at double the tip speed. The centrifuge is formed in the shape of a centrifugal catenary and is constructed of high strength KEVLAR/epoxy composite. This arbon has been spin-tested to a tip ...

Energy Technology Data Exchange (ETDEWEB)

Neutral atom beams with energies above 200 keV may be required for various purposes in magnetic fusion devices following TFTR, JET and MFTF-B. These beams can be produced much more efficiently by electron detachment from negative ion beams than by electron capture by positive ions. We have investigated the efficiency with which such neutral atoms can be produced by electron detachment in partially ionized hydrogen plasma neutralizers.

Energy Technology Data Exchange (ETDEWEB)

Magnetic pulse welding, a cold solid state bonding process, is becoming a viable replacement for conventional fusion welding processes and explosive welding. The process is presented here along with its fundamental equations and applications of similar and dissimilar welds are illustrated along with typical interface microstructures. (orig.) [German] Magnetimpuls-schweissen, ein Verbindungsverfahren im kalten Festzustand, wird ein funktionsfaehiger Ersatz fuer das herkoemmliche Schmelzschweissverfahren und das Explosionsschweissverfahren. Das Verfahren wird hier mit seinen grundlegenden Gleichungen vorgestellt, und Anwendungen von aehnlichen und unaehnlichen Schweissungen werden mit typischen Schnittstellen-Mikrostrukturen veranschaulicht. (orig.)

International Nuclear Information System (INIS)

Thermal hydraulics of a liquid metal is important to design the blanket of a magnetic confined fusion reactor. Since a liquid metal has high thermal and electrical conductivity, the flow characteristics are often different from those of an ordinary liquid like water especially in thermal convection and under a magnetic field. It is difficult to simulate such flows in a liquid metal cooled blanket by water. Flow visualization is a popular method to study thermal hydraulics. Since most of metals are visible by neutron rays, neutron radiography is available to the flow visualization of a liquid metal. The purpose of this study is to develop a visualization technique of the flow in a liquid metal by real-time neutron radiography using the tracer and the dye injection methods. A real-time thermal neutron radiography system of JRR-3M in Japan Atomic Energy Research Institute was used for the visualization test.

Energy Technology Data Exchange (ETDEWEB)

By means of a global mode analysis of ideal MHD modes for Mercier-unstable equilibria in a planar axis L=2/M=10 heliotron/torsatron system with an inherently large Shafranov shift, the conjecture from local mode analysis for Mercier-unstable equilibria given in [N. Nakajima, Phys. Plasmas 3, 4556 (1996)] has been confirmed and the properties of pressure-driven modes, namely, ballooning modes and interchange modes, inherent to such three-dimensional systems have been clarified. The change of the local magnetic shear due to the Shafranov shift, which is related to toroidicity, reduces the field line bending stabilizing effects on ballooning modes. According to the degree of the reduction of the local magnetic shear by the Shafranov shift, the Mercier-unstable equilibria are categorized into toroidicity-dominant (strong reduction) and helicity-dominant (weak reduction) Mercier-unstable equilibria. Since the local magnetic ...

Energy Technology Data Exchange (ETDEWEB)

For heavy-ion beam driven inertial fusion ''liquid-protected'' reactor designs such as HYLIFE-II, a mixture of molten salts made of F{sup 10}, Li{sup -6}, Li{sup 7} and Be{sup 9} (called flibe) allows small chambers and final-focus magnets closer to the target with superconducting coils suffering higher radiation damage, though they can stand only a certain amount of energy deposited before quenching. This work has been primarily focusing on verifying that total energy deposited by fusion neutrons and induced gamma rays remain under such limit values and the final purpose is the optimization of the shielding of the magnetic lens system from the points of view of the geometrical configuration and of the physical nature of the materials adopted. The system is analyzed in terms of six geometrical models going from simplified up to much more realistic representations of a ...

Science.gov (United States)

Exploding Bridgewire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. Fusion Weld . ...

Energy Technology Data Exchange (ETDEWEB)

The effect of weak dissipation on drift orbits has been investigated making use of a simple mapping model in a helical magnetic field. It is found that, after many mapping iterations, any orbit tends to an attractor forming a vortex line even with very small dissipation. The convergence is faster for larger dissipation, i.e., the number of iteration N to converge within a certain distance from the attractor is inversely proportional to the amount of the dissipation. Although the behavior of orbits completely change, the basic stability characteristics of the system does not change, i.e, the coordinate of the attractors are determined by the stable fixed points in the area preserving system because the dissipation is very small. Since wide range of orbits are concentrated around the attractors after many toroidal circulations, a pinch effect is created by a small dissipation. Application of this pinch effect to fusion plasmas is discussed. ...

International Nuclear Information System (INIS)

The plastic deformation behavior of formed CICC for the superconducting Tokamac fusion device was examined and appropriate manufacturing information was provided. A relation between travel of the bending roller and spring back displacement was obtained via virtual manufacturing. The radius of CICC after forming was expressed as a function of the bend-roll travel. The maximum von Mises stress after spring back was also monitored for the SAGBO prediction. Next, the variation of the CICC cross-sectional area was examined during the first turn and during conduit bending with the largest curvature. Finally, the coil radius was measured and compared with the data generated from the virtual manufacturing. The measured data showed similar pattern as predicted one. Using the mapping function found to match with the real data, the data from the virtual manufacturing may facilitate accurate manufacturing.

International Nuclear Information System (INIS)

We discuss the current state of the art in the IGC Internal Tin Nb_3Sn process which routinely is delivering current densities greater than 1 x 10"3 A/mm"2 at 10 Tesla. We focus especially on the conductors suitability for high current density applications such as High Energy Physics and small magnets. Projections are also made as to its suitability for high field applications such as in Fusion. A discussion of the manufacturing process is given with comparisons made to other accepted Nb_3Sn processes and NbTi. Superconductor characteristics such as filament quality and Nb_3Sn phase uniformity are compared to those obtained in conventional bronze process.

Energy Technology Data Exchange (ETDEWEB)

A method to deduce the 2 x 2 transport matrix for coupled heat and particle transport in Tokamaks is proposed. The method applies to perturbative experiments, and is based on a Fourier transform of the measured signals of temperature and density. By analyzing different linear combinations of temperature and density, the eigenvectors and eigenvalues of the transport matrix are determined. The method is tested for a number of illustrative cases using simulated data, and the sensitivity to noise on the signals is evaluated. (author).

Energy Technology Data Exchange (ETDEWEB)

An interpretive theory of trace impurity transport in tokamaks is presented. It is based on an earlier phenomenological approach developed by the authors for describing tokamak plasma transport experiments. The present model is used to explain disparate phenomena observed in ALCATOR C and DITE in a unified phenomenological framework. Predictive numerical calculations are presented for DITE conditions. If experimentally confirmed, the model could be used to correlate plasma properties with trace impurity behaviour. (orig.)

Science.gov (United States)

This talk will summarize key features of three conceptual fusion neutron test facilities designed in the early 1980s: TASKA,^1 TDF,^2 and TASKA-M.^3 Motivated by the accessibility and maintainability of cylindrical geometry, these magnetic-mirror designs possess a simple central cell, as in a fusion neutron test facility based on the gas dynamic trap (GDT).^4 The TASKA-M design, like today's GDT designs, included the injection of neutral beams into the central cell to create a sloshing-ion distribution that gives density peaks near the materials test modules. In TASKA and TDF, the minimum-B end-cell designs contained thermal barriers, regions of low electrostatic potential to reduce electron flow between central cell and end cells. Thermal barriers improve performance but require more complicated input power systems, and their physics basis is less well established than that of simple mirrors. For TASKA-M, a more ...

Energy Technology Data Exchange (ETDEWEB)

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.

International Nuclear Information System (INIS)

... range magnetic fields magnetic susceptibility magnetization neutron diffraction

Science.gov (United States)

The potential public safety impacts from accidents in conceptual fusion power plants were investigated. Fusion was found to have some potential for accidents, as does any energy generating system. Functions of fusion power plants were identified that possess sufficient potential for an accidental release of toxic materials to the environment. An assessment was made of the impact of the potential accidents and recommendations are included for R and D that will allow incorporation of safety concerns in fusion power plant design. This work was based on a review of information available in conceptual design documents of fusion reactor systems.

International Nuclear Information System (INIS)

The most important and difficult part of materials research for fusion reactor is realized to be irradiation studies of fusion reactor materials. Irradiation studies of fusion reactor materials utilizing FFTF/MOTA, as one of Japan/U.S.A. Fusion Collaboration Programs, have important role to establish fundamental understanding of heavy irradiation effects on materials behavior and properties and to develop methods and technologies for advanced irradiation studies under fusion reactor environment. This paper briefly reviews the history, the state of the art, and the future of the FFTF/MOTA program. (author).

Science.gov (United States)

... the open source OpenMap Java toolkit from BBN ... 2001), Handbook of Multisensor Data Fusion ... Oxenham (2002), Sensor Registration Using Airlanes ...

International Nuclear Information System (INIS)

The major activities of the various Institute's departments are highlighted. The following departments are included: (i) Tokamak; (ii) Pulse plasma systems; (iii) Thermal plasma; (iv) Materials engineering; (v) Laser plasma; and (vi) Optical diagnosis. (P.A.)

International Nuclear Information System (INIS)

A clear and reproducible transition to a regime with an improved particle confinement is routinely observed on the CASTOR tokamak, if the biasing electrode is inserted deep enough into the plasma (r/a?0.5) and biased up to +250 V. The steepening of the radial profiles of the plasma density and potential demonstrate the formation of a transport barrier just inside the last closed flux surface. Fast relaxations of the edge plasma parameters, with a frequency of about 10 kHz, are observed when the average radial electric field within the barrier prevails values of about 20 kV/m. A detailed analysis of the spatial-temporal behaviour of these relaxations is presented.

Energy Technology Data Exchange (ETDEWEB)

Washboard (WB) modes (Smeulders P et al 1999 Plasma Phys. Control. Fusion 41 1303) are a very common edge instability regularly observed in the H-mode regime in JET. They are detected as (normally several) bands of continuously fluctuating magnetic activity rotating in the direction of the electron diamagnetic drift with typical frequencies in the range of 10-90 kHz. The time evolution of the WB mode frequency is found to follow qualitatively the evolution of the electron temperature measured near the pedestal top, probably due to the strong diamagnetic drift associated with the large pedestal gradients. Evidence for their involvement in the pedestal and ELM dynamics will be presented. Increasing WB mode amplitude is correlated with an increase in the time between consecutive type-I ELMs. In situations in which a sudden increase (decrease) of WB mode activity is observed, the build-up of the pedestal temperature (and, linked to this, also of ...

International Nuclear Information System (INIS)

... parameters magnetic fields magnetic properties magnetization monocrystals

International Nuclear Information System (INIS)

... of Sciences (Poland) [5.48 Megabytes] NUCLEAR PHYSICS AND RADIATION

Energy Technology Data Exchange (ETDEWEB)

The effect of nuclear scattering on the suprathermal fusion probability of recoiling d-t nuclei under the impact of fusion products, a 14.1-MeV neutron and a 3.5 MeV alpha particle, in thick pellets is investigated with the help of the Boltzmann-Fokker-Planck equation. Although the suprathermal fusion from alpha-particle recoils is quite small, the one originating from neutron recoils is considerable.

KoreaScience (Korea)

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International Nuclear Information System (INIS)

Electron and ion beam dynamics of the PF-1000 facility were investigated for the first time at its upper energy limit (?1 MJ) in relation to neutron emission, the pinch's plasma ('target') characteristics and some other parameters with the help of a number of diagnostics with ns temporal resolution. Special attention was paid to the temporal and the spatial cross correlations of different phenomena. Results of these experiments are in favour of a neutron emission model based on ion beam-plasma interaction with three important features: (1) the plasma target is hot and confined during a few 'inertial confinement times'; (2) the ions of the main part of the beam are magnetized and entrapped around the pinch plasma target for a period longer than the characteristic time of the plasma inductive storage system and (3) ion-ion collisions (both fusion collisions, due to head-on impacts and Coulomb collisions) are responsible for neutron emission. ...

Energy Technology Data Exchange (ETDEWEB)

The excellent high temperature strength and thermal conductivity of molybdenum-base alloys provide attractive features for components in advanced magnetic and inertial fusion devices. Refractory metal alloys react readily with oxygen and other gases. Oxidized molybdenum in turn is susceptible to losses from volatile molybdenum trioxide species, (MoO3)m, in air and the hydroxide, MoO2(OH)2, formed from water vapor. Transport of radioactivity by the volatilization, migration, and re-deposition of these volatile species during a potential accident involving a loss of vacuum or inert environment represents a safety issue. In this report we present experimental results on the oxidation, volatilization and re-deposition of molybdenum from TZM in flowing air between 400 and 800°C. These results are compared with calculations obtained from a vaporization mass transfer model using chemical thermodynamic data for vapor pressures of MoO3(g) over ...

International Nuclear Information System (INIS)

Fusion energy has been studied in many countries such as U.S., France, Japan, Korea etc. Because it would provide much more energy for a given weight of fuel than any technology currently in use, and the fuel itself (primarily deuterium) exists abundantly in the Earth's ocean. Nuclear fusion reactor uses tritium and deuterium as fuel while nuclear fission reactor uses uranium and plutonium as fuel. Besides, inherent design characteristics and driving condition of nuclear fusion reactor is different from those of nuclear fission reactor. Therefore, we cannot apply the regulation rules of nuclear fission reactor to nuclear fusion reactor without change and thus it is needed to development of the safety regulation concept which reflects the characteristics of nuclear fusion reactor. Safety regulation of nuclear fusion reactor employs deterministic approach until ...

DEFF Research Database (Denmark)

We present an experimental study of vesicle fusion using light and neutron scattering to monitor fusion events. Vesicles are reproducibly formed with an extrusion procedure using an single amphiphile triethylene glycol mono-n-decyl ether in water. They show long-term stability for temperatures around 20 C, but at temperatures above 26 C we observe an increase in the scattered intensity due to fusion. The system is unusually well suited for the study of basic mechanisms of vesicle fusion. The vesicles are flexible with a bending rigidity of only a few k(H)T. The monolayer spontaneous curvature, Ho, depends strongly on temperature in a known way and is thus tunable. For temperatures where H-0 > 0 vesicles tyre long-term stable, while in the range H-0 < 0 the fusion rate increases the more negative the Spontaneous curvature Through a quantitative;analysis of the ...

International Nuclear Information System (INIS)

We prove a generalization of the Verlinde formula to fermionic rational conformal field theories. The fusion coefficients of the fermionic theory are equal to sums of fusion coefficients of its bosonic projection. In particular, fusion coefficients of the fermionic theory connecting two conjugate Ramond fields with the identity are either one or two. Therefore, one is forced to weaken the axioms of fusion algebras for fermionic theories. We show that in the special case of fermionic W(2, #delta#)-algebras these coefficients are given by the dimensions of the irreducible representations of the horizontal subalgebra on the highest weight. As concrete examples we discuss fusion algebras of rational models of fermionic W(2, #delta#)-algebras including minimal models of the N = 1 super Virasoro algebra as well as N = 1 super W-algebras SW(3/2, #delta#). (orig.).

Science.gov (United States)

... Title : Refining the Magnetic Forming Capability. ... Abstract : The purpose of this project was to refine the in-house magnetic forming capability. ...

Science.gov (United States)

... Examples include magnetic forming tools, magnetic shielding, magnetohydrodynamic propulsion systems, and various magnetic containment ...

J-STORE (Japan)

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International Nuclear Information System (INIS)

Particulate (i.e. tokamak dust) has been collected from the DIII-D tokamak located at General Atomics in San Diego, CA, USA. Two methods were used to collect particulate with the goal of preserving the particle size distribution and physical characteristics of the particulate. Vacuum collection on substrates and adhesion removal with metallurgical replicating tape were chosen as non-intrusive sampling methods. Sampling was completed in four toroidal locations of the machine; the 0-90 area, the 90-180 area, the 180-270 area, and the 270-360 area. The 0 direction designates the north side of the DIII-D machine. Four tiles in each area were sampled; the first vertical tile above the floor on the centerpost, a floor tile next to the center post, a tile on the isolated ring, and the first tile up from the isolated ring on the divertor. In addition, samples were collected from underneath the floor tiles at the 275 and the 75 locations. The count ...

UK PubMed Central (United Kingdom)

The hemagglutinin (HA) glycoprotein of influenza virus performs two critical roles during infection: it binds virus to cell surface sialic acids, and under mildly acidic conditions it induces fusion...Full Text Available

UK PubMed Central (United Kingdom)

The fusogenic orthoreoviruses express nonstructural fusion-associated small transmembrane (FAST) proteins that induce cell-cell fusion and syncytium formation. It has been speculated that the FAST proteins...Full Text Available

UK PubMed Central (United Kingdom)

To gain insight into the process of mitochondrial transmission in yeast, we directly labeled mitochondrial proteins and mitochondrial DNA (mtDNA) and observed their fate after the fusion of two cells....Full Text Available

UK PubMed Central (United Kingdom)

The existence and importance of an accelerated adjacent segment disc degeneration (ASD) after lumbar fusion have previously not been demonstrated by RCTs. The objectives of this study were, to determine...Full Text Available

International Nuclear Information System (INIS)

Tokamaks with sufficiently strong supplementary heating develop non-Maxwellian electron velocity distributions. Because the absorption of electron cyclotron power is proportional to #nabla#_Vf, even small deviations from a Maxwellian distribution can significantly affect power deposition. Following an approach used to study microinstabilities in a plasma with an arbitrary, numerically specified, electron distribution, we have developed a computational module to study electron cyclotron power deposition in plasmas that have distributions motivated by those in actual tokamaks. Also, we compare the deposition results obtained using an energy balance approach with those obtained using a Taylor expansion of the dielectric tensor. We illustrate the limitations of the latter approach.

Science.gov (United States)

To estimate the waste management needs of a fusion power reactor, a scheme for handling radioactive waste from a fusion plant has been devised. The handling scheme proceeds with radioactive waste, primarily from blanket replacement, being stored on-site; waste in cooled and shielded casks is then isolated off-site; finally, the materials are recycled. Using activities and component lifetimes supplied by designers, several conceptual fusion power reactors have been analyzed and their waste streams compared to fission reactors with regard to total activity, specific activity, and lifetimes of activity.

KoreaScience (Korea)

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Science.gov (United States)

For abstract, see NSA 29 07, number 17425.

Science.gov (United States)

The maximum fissile fuel production capacity of three conceptual fusion breeder systems is examined on the basis of the dominant isotopic-balance processes. Compact relationships involving system power output, plasma and energy multiplication, and parameters which describe the fuel cycle and neutron spectrum in the blanket are established. It is found that the fusion breeder, as characterized herein, possesses a substantial fissile fuel breeding capacity the extent of which is governed primarily by the neutron spectrum in the conversion blanket and the break-even condition of the plasma.

CERN Document Server

Specification of the steel sheet for the 300 GeV magnet system

International Nuclear Information System (INIS)

... fields magnetic moments neel temperature neutron diffraction order-disorder

Science.gov (United States)

Magnetic forming coil design and development

CERN Document Server

Large scale magnetic field measurements and mapping

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

The effect of a sawtooth crash on the radial distribution of the slowing down fusion product tritons and on beams ions, is examined with measurements of the 2.5 MeV and 14 MeV neutron emission line-integrals before and after sawtooth crashes. In deuterium discharges, the 14 MeV neutron production was wholly attributable to burnup of the 1 MeV fusion product tritons from d-d fusion. The local emissivity of 14 MeV neutrons, and hence of the profile of thermalizing tritons, is shown to be only weakly affected by crashes in the discharges studied. This is in contradiction with the apparent behaviour of injected beam ions as deduced from a study of the considerable changes in local emissivity of the 2.5 MeV neutrons. Nevertheless, the behaviour of the fusion product tritons is consistent with the scaling of the beam injected deuterium. 1 ref., 6 figs.

Energy Technology Data Exchange (ETDEWEB)

A summary of the topics covered in papers presented at the 1995 Brookhaven joint conference on production, neutralization, and application of negative ion beams is given. The conference topics covered included plasma ion sources, plasma seeding of these sources for increased ion production, beam extraction and transport, computer simulation and design studies, and operation of existing and experimental ion source facilities. Application of the sources to accelerator, tokamak, and thin film deposition are discussed. (AIP) {copyright} {ital 1996 American Institute of Physics.}

International Nuclear Information System (INIS)

Comparison of plasma density increase was carried out in outer and inner channels of the interferometer in T-11M tokamak. There were two cases of gas puffing: by outer valve or upper one. Amplitude of difference of the plasma density increase consisted of 9% near the outer valve. Perturbation of the electric potential e?1/Te can have similar value. This perturbation can lead to appearance of the additional losses.

International Nuclear Information System (INIS)

This issue of the newsletter on Engineering Design Activities (EDA) for the ITER Tokamak project contains a report on Second International Industries' Liaison meeting which was held in Tokyo on 2-4 April 1997 (by Y. Kaneki, JAIF, Japan); an overview report on the Blanket project (by A. Cardella, I.Ioki (ITER Central Team), W. Daenner (EU Home Team)); and a progress report on microwave reflectometry (by J. Sanchez, Madrid, Spain).

Energy Technology Data Exchange (ETDEWEB)

The effect of finite gyroradius on the current diffusive ballooning mode is examined. Starting from the reduced MHD equations including turbulent transports, coupling with drift motion and finite gyroradius effect of ions, we derive a ballooning mode equation with complex transport coefficients. The eigenfrequency, saturation level and thermal diffusivity are evaluated numerically from the marginal stability condition. Preliminary results of their parameter dependence is presented. (author)

International Nuclear Information System (INIS)

A linear induction accelerator that produces a beam of energetic heavy ions (T #approx =# 10 GeV, A #approx =# 200 am#mu#) is a prime candidate as a driver for an inertial fusion power plant. Some early perceptions were that heavy-ion driven fusion would not be cost-competitive with other power sources because of the high cost of the accelerators. However, improved understanding of the physics of heavy-ion transport and acceleration (supported by experimental results), combined with advances in accelerator technology, have resulted in accelerator design costs -- 50% of previous estimates. As a result, heavy-ion driven fusion power plants conceptual fusion power plants. A brief formulation of transport and acceleration physics is presented here, along with a description of the induction Linac cost optimization code LIACEP. Cost trends are presented and discussed, along with specific cost estimates for ...

International Nuclear Information System (INIS)

The results of experiments with a short period (9.6 mm) wiggler sheet electron beam (1.0 mm x 2.0 cm) millimeter-wave free electron laser (FEL) amplifier are presented. This FEL amplifier utilized a strong wiggler field for sheet beam confinement in the narrow beam dimension and an offset-pole side-focusing technique for the wide dimension beam confinement. The beam analysis herein includes finite emittance and space-charge effects. High-current beam propagation was achieved as a result of extensive analytical studies and experimental optimization. A design optimization resulted in a low sensitivity to structure errors and beam velocity spread, as well as a low required beam energy. A maximum gain of 24 dB was achieved with a 1-kW injected signal power at 86 GHz, a 450-kV beam voltage, 17-A beam current, 3.8-kG wiggler magnetic field, and a 74-period wiggler length. The maximum gain with a one-watt injected millimeter-wave power was observed to be over 30 dB. The ...

International Nuclear Information System (INIS)

We investigate the magnetic braking of the core of an axisymmetric cloud whose rotation axis is parallel to the mean direction of the magnetic field. (author).

Energy Technology Data Exchange (ETDEWEB)

The magnetic fluid is a colloidal suspension of magnetite in kerosene, prepared by a low-cost process. Separation is accomplished in an open trough filled with magnetic fluid. A magnetic field is established in the fluid, by energizing an electromagnet having poles on each side of the trough. Due to the design of the magnet poles and air gaps, the magnetic field is strongest at the bottom, about 10,000 oersteds, and uniformly decreases in strength to about 2000 oersteds at the top of the fluid. Therefore, the magnetic field gradient increases with depth. The magnetic force attracts the entire separation medium (magnetic fluid) creating a reaction force of equal magnitude and acting in the opposite direction. This reaction created within a magnetic fluid/magnetic field combination ...

International Nuclear Information System (INIS)

The cold fusion reactions leading to superheavy elements with Z=104-116 has been discussed in our model recently [5]. Presently we shortly discuss our model and extend our consideration to fusion reactions ("8"6Kr, "8"7Rb, "8"8Sr)+"2"0"8Pb and "8"6Kr+"2"0"9Bi leading to elements with Z=118-120. The available experimental cross-section data for the reactions are well described.

Energy Technology Data Exchange (ETDEWEB)

In this paper the diffusion of tritiated water vapor into concrete walls is studied to evaluate tritiated water retention capacity of a fusion reactor concrete building. Using a model of the tritiated water diffusion determined form experimental results, depth profiles of tritiated water in concrete are calculated in the case of being exposed to air containing tritiated water vapor during the normal operational condition of a fusion reactor. A 0.5-m-thick concrete is sufficient for reactor hall walls from a viewpoint of the tritium containment.

Energy Technology Data Exchange (ETDEWEB)

Molar enthalpies of sublimation of 1,2,4-, 1,2,3-, and 1,3,5-tri-hydroxy-benzene, were obtained from the temperature dependence of the vapor pressure measured by the transpiration method. The molar enthalpies of fusion and molar heat capacities of these compounds were measured by DSC. The measured data sets of vaporization, sublimation and fusion enthalpies were checked for internal consistency. Strength of the inter- and intra-molecular hydrogen bonding in di- and tri-hydroxy-benzenes have been assessed.

International Nuclear Information System (INIS)

The problem of fast wave plasma heating in reactor-torsatron at the ICRF range in scenarios, optimal for fusion reactor, is numerically studied.

UK PubMed Central (United Kingdom)

This paper proposes a new approach based on missing value pattern discovery for classifying incomplete data. This approach is particularly designed for classification of datasets with a small...Full Text Available

British Library Electronic Table of Contents (United Kingdom)

LLNL is developing the nuclear fusion based Laser Inertial Fusion Energy (LIFE) power plant concept. The baseline design uses a depleted uranium (DU) fission fuel blanket with a flowing molten salt coolant (flibe) that also breeds the tritium needed to sustain the fusion energy source. Indirect drive targets, similar to those that will be demonstrated on the National Ignition Facility (NIF), are ignited at 13Hz providing a 500MW fusion source. The DU is in the form of a uranium oxycarbide kernel in modified TRISO-like fuel particles distributed in a carbon matrix forming 2-cm-diameter pebbles. The thermal power is held at 2000MW by continuously varying the 6Li enrichment in the coolants. There are many options to be considered in the engine design including target yield, U-to-C ratio in th...

International Nuclear Information System (INIS)

Microstructure and properties of a Mg AZ31B laser beam weld without filler are studied using electron microscopy, X-ray diffraction and mechanical tests. The microstructure of the weld is characterized by a narrow heat affected zone, columnar grains and precipitate coarsening in the fusion zone. Texture in the fusion zone is significantly different from the texture of the base material. The residual stress distribution observed is similar at the top and the bottom of the weld, maximum tensile residual stress values are observed in the fusion zone. Tensile tests reveal differences in the mechanical behavior of the fusion zone and the parent material, which can be related to the differences of texture and the resulting deformation mechanisms.

Science.gov (United States)

goals for multisensor co-registration and fusion. 6 - 12.5 Km ..... Beta-Test toolkit for cyclogenesis and early evolution of cyclones ...

Science.gov (United States)

... coordinates to allow for multisensor fusion, trajectory ... of an image processing toolkit (iPTK ... effectiveness of data-driven registration processing, spatial ...

Science.gov (United States)

... Title : ERG Expression Levels in Prostate Tumors Reflect Functional Status of the Androgen Receptor (AR) as a Consequence of Fusion of ERG ...

Energy Technology Data Exchange (ETDEWEB)

It is planned to bulk-heat a unit cell of a fusion reactor solid-breeder blanket in a fission reactor to study thermo-mechanical and thermal-hydraulic properties of fusion blankets. This study investigates the neutronic feasibility of using the Power Burst Facility (PBF) for this purpose. Heating rates were calculated for a Li/sub 2/O experiment placed in the PBF test space. The ANISN code and a 56-group coupled neutron-gamma library based on FLUNG and VITAMIN C were used to compute the heating rates. The results show that an average heating rate level of 1-3 W/cc can be produced in PBF with a local power profile that should be typical of a fusion blanket unit cell.

Energy Technology Data Exchange (ETDEWEB)

A simple semianalytical calculation is used to study how a star reacts when its central stock of hydrogen is exhausted and before the next fusion reaction based on helium begins.

Energy Technology Data Exchange (ETDEWEB)

Both travelers were members of a nine-person US delegation that participated in an international workshop on accelerator-based 14 MeV neutron sources for fusion materials research hosted by the University of Tokyo. Presentations made at the workshop reviewed the technology developed by the FMIT Project, advances in accelerator technology, and proposed concepts for neutron sources. One traveler then participated in the initial meeting of the IEA Working Group on High Energy, High Flux Neutron Sources in which efforts were begun to evaluate and compare proposed neutron sources; the Fourth FFTF/MOTA Experimenters' Workshop which covered planning and coordination of the US-Japan collaboration using the FFTF reactor to irradiate fusion reactor materials; and held discussions with several JAERI personnel on the US-Japan collaboration on fusion reactor materials.

KoreaScience (Korea)

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KoreaScience (Korea)

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KoreaScience (Korea)

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J-STORE (Japan)

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KoreaScience (Korea)

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International Nuclear Information System (INIS)

... radiations isotopes magnetic moments nuclear cascades nuclear properties

Science.gov (United States)

... magnetic containment field lines which is zero on the center line of the toroidal containment tube and increases in magnitude with ...

KoreaScience (Korea)

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International Nuclear Information System (INIS)

In order to examine the state of technology of all areas of magnetic suspension and to review related recent developments in sensors and controls approaches, superconducting magnet technology, and design/implementation practices, a symposium was held. The proceedings are presented. The sessions covered the areas of bearings, sensors and controls, microgravity and vibration isolation, superconductivity, manufacturing applications, wind tunnel magnetic suspension systems, magnetically levitated trains (MAGLEV), space applications, and large gap magnetic suspension systems.

Science.gov (United States)

The macroscopic rotation of plasma in a toroidal containment device is an important feature of the equilibrium. Toroidal and polidal rotation in the high-beta tokamak Torus II is measured experimentally by examining the Doppler shift of the 4685.75 A He II line emitted from the plasma. The toroidal flow at an average velocity of 1.6 x 10/sup 6/ cm/sec, a small fraction of the ion thermal speed, moves in the same direction as the toroidal-plasma current. The poloidal flow follows the ion diamagnetic current direction, also at an average speed of 1.6 x 10/sup 6/ cm/sec. In view of certain ordering parameters, the toroidal flow is compared with predictions from neoclassical theory in the collisional, Pfirsch-Schluter regime. The poloidal motion, however, results from an E x B drift in a positive radial electric field, approaching a stable ambipolar state. This radial electric field is determined from theory by using the measured poloidal velocity. Mechanisms for the ...

International Nuclear Information System (INIS)

The study of the scrape-off layer (SOL) during Alfven wave heating may lead to a better understanding of the antenna-plasma interaction. The scrape-off layer of the TCA tokamak has been widely investigated by means of Langmuir probes. The aim of this work is to present measurements on the influence of the Alfven wave spectrum on the scrape-off layer. These experiments have shown that the plasma boundary layer is strongly affected by the wave field, in particular the ion saturation current and the floating potential. In TCA, as the spectrum evolves due to a density rise, the passage of the Alfven continua and their associated eigenmodes, the Discrete Alfven Wave (DAW) induces a strong depletion in the edge density of up to 70% during the continuum part and a density increase during the crossing of an eigenmode. The floating potential becomes negative during the continua and even more negative crossing the eigenmodes. In case of MHD mode activity, this behaviour ...

International Nuclear Information System (INIS)

A non-contact method, using magnetic drag force principle, was proposed to design the braking systems to improve the shortcomings of the conventional braking systems. The extensive literature detailing all aspects of the magnetic braking is briefly reviewed, however little of this refers specifically to upright magnetic braking system, which is useful for industries. One of the major issues to design upright magnetic system is to find out the magnetic flux. The changing magnetic flux induces eddy currents in the conductor. These currents dissipate energy in the conductor and generate drag force to slow down the motion. Therefore, a finite element model is developed to analyze the phenomena of magnetic flux density when air gap and materials of track are varied. The verification shows the predicted magnetic flux is within ...

Energy Technology Data Exchange (ETDEWEB)

This report discusses the following topics: Fusion-fission in light nuclear systems; High-resolution Q-value measurement for the {sup 24}Mg+{sup 24}Mg reaction; Heavy-ion reactions and limits to fusion; and Hybrid MWPC-Bragg curve detector development.

Energy Technology Data Exchange (ETDEWEB)

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.

International Nuclear Information System (INIS)

The conceptual system requirements for the control, data, robotics, and project management (CDRM) system for the next generation of fusion experiments are developed by drawing on the success of the Tara control and data system. The requirements are described in terms of an integrated but separable matrix of well-defined interfaces among the various systems and subsystems. The study stresses modularity, performance, cost effectiveness, and exportability.

International Nuclear Information System (INIS)

This illustrated booklet describes the fission process; the use of uranium to produce power in nuclear power stations (and a brief explanation of the differences between the principal types of reactor); the formation of plutonium and fission products; radioactive wastes and their management; nuclear fusion and a conceptual fusion reactor; alpha, beta and gamma radiations; radioisotopes and their applications. (U.K.).

International Nuclear Information System (INIS)

Under the direction of the NASA-Glenn Research Center, the Edison Welding Institute (EWI) in Columbus, OH performed a series of non-fusion joining experiments to determine the feasibility of joining refractory metals or refractory metal alloys to Ni-based superalloys. Results, as reported by EWI, can be found in the project report for EWI Project 48819GTH (Attachment A, at the end of this document), dated October 10, 2005. The three joining methods used in this investigation were inertia welding, magnetic pulse welding, and electro-spark deposition joining. Five materials were used in these experiments: Mo-47Re, T-111, Hastelloy X, Mar M-247 (coarse-grained, 0.5 mm to several millimeter average grain size), and Mar M-247 (fine-grained, approximately 50 (micro)m average grain size). Several iterative trials of each material combination with each joining method were performed to determine the best practice joining method. Mo-47Re was found to be ...

Energy Technology Data Exchange (ETDEWEB)

Three-dimensional dynamics of a compact toroid (CT) plasmoid, which is injected into a magnetized target plasma region is investigated by using magnetohydrodynamic (MHD) numerical simulations. It is found that the process of the CT penetration into this region is much more complicated than what has been analyzed so far by using a conducting sphere (CS) model. The injected CT suffers from a tilting instability, which grows with the similar time scale as the CT penetration. The instability is accompanied by magnetic reconnection between the CT magnetic field and the target magnetic field, which disrupts the magnetic configuration of the CT. Magnetic reconnection plays a role to supply the high density plasma initially confined in the CT magnetic field into the target region. Also, the penetration depth of the CT high density plasma is ...

International Nuclear Information System (INIS)

Potassium clusters arrayed in zeolite A are known to show ferromagnetic properties at low temperature. The origin of the spontaneous magnetization has been explained by a model of spin-canting in an antiferromagnetically ordered state. The direct information for the magnetic structure, however, has not been obtained so far. In the present work, we measure the neutron powder diffraction by using pulsed neutron source at KEK-KENS below and above the Curie temperature. No significant temperature-dependence was, however, obtained within the statistical errors, namely, magnetic scattering could not be detected separately. We also estimate the intensity of magnetic scattering by assuming some possible magnetic structures with considering the magnetic form factor of the cluster wave function. The intensity of magnetic scattering is estimated to be ...

Energy Technology Data Exchange (ETDEWEB)

A number of interactions between magnetic fields and matter is reviewed. The resulting forces range in magnitude from the very large, obtained in high-energy fields, to the weak ones caused by the magnetostriction of ferromagnets. The fundamentals of these interactions are highlighted, and the examples discussed are forces on dipoles, particle alignment, magnetostrictive forces, magnetic forming, magnetic stirring, levitation melting, and magnetic pulsing of tool steels. (orig.)

Energy Technology Data Exchange (ETDEWEB)

The integrity of a pipeline system is determined by its weakest links which may be the joints. Heat fusion is the most common method for joining gas distribution polyethylene (PE) piping. There are procedural, thermal, and mechanical aspects of making fusion joints. Acceptable procedural aspects, such as heater calibration and cleanliness, can be assured by rigorous training and certification of the operators. Thermal and mechanical aspects consist of specifying joining conditions such as the heater temperature, heating time, and joining pressure. In the absence of procedural errors, the strength of a fusion joint should depend on the pipe material, pipe dimensions, and the thermal and mechanical joining conditions. Socket heat fusion was studied both experimentally and analytically to determine how the strength of the joint varied with the conditions under which it was made. The standard tensile impact ...

International Nuclear Information System (INIS)

Tungsten (W) coating on fusion candidate V-4Cr-4Ti (NIFS-HEAT-2) substrate was demonstrated with plasma spray process for the purpose of applying to protection of the plasma facing surface of a fusion blanket. Increase in plasma input power and temperature of the substrate was effective to reduce porosity of the coating, but resulted in hardening of the substrate and degradation of impact property at 77 K. The hardening seemed to be due to contamination with gaseous impurities and deformation by thermal stress during the coating process. Since all the samples showed good ductility at room temperature, further heating seems to be acceptable for the vanadium substrate. The fracture stress of the W coating was estimated from bending tests as at least 313 MPa, which well exceeds the design stress for the vanadium structure in fusion blanket. (author)

Energy Technology Data Exchange (ETDEWEB)

The subscale Varestraint test has been used to determine the relative hot cracking susceptibility of the fusion zone in four commercial heats of alloy 800. Although all four heats were susceptible to cracking, one heat exhibited a significant increase in cracking relative to the other three. Optical metallography revealed that nearly all the cracking was localized along fusion zone grain boundaries. Microprobe analysis of the grain boundaries detected high concentrations of titanium, silicon, and niobium resulting from partitioning during solidification. The fusion zone hot cracking mechanism in alloy 800 involves the complex interaction of titanium, silicon, niobium, and carbon along the solidification boundaries. SEM and Auger analyses of the hot crack fracture surfaces revealed the presence of (Ti, Nb)-rich carbides, suggesting that these particles precipitate from the liquid which solidifies last on the fracture ...

CERN Document Server

We provide a first-principles, perturbative derivation of the AdS5/CFT4 Y-system that has been proposed to solve the spectrum problem of N=4 SYM. The proof relies on the computation of quantum effects in the fusion of some loop operators, namely the transfer matrices. More precisely we show that the leading quantum corrections in the fusion of transfer matrices induce the correct shifts of the spectral parameter in the T-system. As intermediate steps we study UV divergences in line operators up to first order and compute the fusion of line operators up to second order for the pure spinor string in AdS5xS5. We also argue that the derivation can be easily extended to other integrable models, some of which describe string theory on AdS4, AdS3 and AdS2 spacetimes.

Energy Technology Data Exchange (ETDEWEB)

An analytic model of magnetic torques applied to an accreting neutron star is employed to evaluate the magnetic dipole moments of x-ray pulsars. A new type of close binary system containing a neutron star is suggested.

Science.gov (United States)

The past decade has seen the development of eddy current probes for inspection of the mildly ferro-magnetic alloy Monel 400. Due to the rapid advances in permanent magnet technology similar probes have been upgraded to magnetically saturate, and hence ins...

International Nuclear Information System (INIS)

Parameters of permanent magnets result from the combination of intrinsic properties such as saturation magnetization, magnetic exchange, and magnetocrystalline energy, as well as microstructural parameters such as phase structure, grain size, and orientation. Reduction of grain size into nanocrystalline regime (#approx# 50 nm) leads to the enhanced remanence which derives from ferromagnetic exchange coupling between highly refined grains. In this study the fundamental phenomena, quantities, and structure parameters, which define nanophase permanent magnets are presented and discussed. The theoretical considerations are confronted with experimental data for nanocrystalline Sm-Fe-N type permanent magnets. (author)

UK PubMed Central (United Kingdom)

OBJECTIVE--The study was performed to examine the influence of the exposure to magnetic fields in the potrooms of an electrolysis plant on the occurrence of musculoskeletal symptoms among the employees....Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The Muon Ionization Cooling Experiment (MICE) focusing solenoid magnets focus the muon beam within the MICE cooling channel on a liquid or solid absorber that is within the warm bore of solenoid. The focusing magnet has a warm bore of 470 mm. his magnet consists of two coils 210-mm long that is separated by an aluminum mandrel that is 200 mm long. Each of the coils has its own leads. The coils may be operated in either the non-flip mode (solenoid mode with both coils at the same polarity) or the lip mode (quadrupole focusing mode where both coils are at opposite polarity). This report describes the focusing solenoid magnet design that will be built by the vendor. The progress on the construction of the first of the focusing magnets will also be discussed in this report. Ultimately three of these magnets will be built. These magnets will be ...

Science.gov (United States)

... 31. New electric forming methods offer potentials for light metals; magnetic forming and plasma forming. ... 3, 25 Magnetic Forming ..... ...

International Nuclear Information System (INIS)

Highly ordered arrays of Ni nanoholes and Fe20Ni80 antidots have been prepared, respectively, by replica/antireplica processing and sputtering techniques using nanoporous alumina membranes as templates. Geometrical characteristics as nanohole/antidot diameter, interpore distance and the overall hexagonal symmetry of arrays are controlled through the original templates. Experimental data on their hysteresis and magnetic domain structure have been taken by vibrating sample magnetometry and magnetic force microscopy, respectively. An analysis of the magnetization process, resulting magnetic anisotropy and magnetic domain structure is summarized considering the influence of those geometry aspects. In particular, the hexagonal symmetry and the density of nanohole/antidots determine the overall magnetic behavior, which is of interest in future high-density ...

Science.gov (United States)

... M(TH) in applied magnetic fields up to ± 7 T and for temperatures ranging from 2 to 300 K. The superparamagnetic (SPM) behavior of these metallic ...

International Science & Technology Center (ISTC)

Development of Portable Normobaric Hypoxia and Pulsed Magnetic Field Firmware System for Enhancement of Radio- and Non-specific Resistance in Workers of Environmentally Hazardous Industries

International Nuclear Information System (INIS)

... dipole moments magnetic fields monocrystals neutron diffraction order-disorder

Science.gov (United States)

With the increased costs of maintaining boilers and chillers entrepreneurs around the country have offered magnetic and similar devices to facilities as viable alternatives to their maintenance program. This report gives a brief history of some of the pre...

Science.gov (United States)

Magnetic coil pressure wave generation for magnetic forming

Energy Technology Data Exchange (ETDEWEB)

From optical point of view and due to the magnetic interaction of the cold neutrons with the unpaired electron shell, magnetic materials hae a neutron spin-dependent refractive index n[sup +] [spin up] and n[sup -] [spin down]. Magnetic media such as Fe, Co and Ni react like birefringent uniaxial crystals in ordinary optica. n[sup +] and n[sup -] are the equivalent of the ordinary and extraordinary refractive indices. The specular reflection of spin polarized neutrons which is due to the discontinuity of the magnetic induction at the surface of the ferromagnet is a sensitive probe of surface and interface magnetism. We shall first give the background of the art of polarized neutron optics. Secondly, some recent examples from surface and interface magnetism will be given to illustrate the power of this technique such as the magnetic coupling ...

Science.gov (United States)

magnet research at several national laboratories through its Advanced Accelerator Technology Program. The HEP Conductor Development Program, a collaboration among national...

Science.gov (United States)

as for direct energy conversion in specialized direct electrical energy conversion plants. Figure 1. An energetic (~163KeV) proton and a 11boron nucleus fuse ...

Energy Technology Data Exchange (ETDEWEB)

The purpose of this study is to determine the thermal reliability of stearic acid, palmitic acid, myristic acid and lauric acid as latent heat energy storage materials with respect to various numbers of thermal cycles. The fatty acids, as phase change materials (PCMs), of industrial grade (purity between 90% and 97%) were subjected to accelerated thermal cycle tests. The differential scanning calorimetry (DSC) analysis technique was applied to the PCMs after 0, 120, 560, 850 and 1200 melt/freeze cycles in order to measure the melting temperatures and the latent heats of fusion of the PCMs. The DSC results indicated that the change in melting temperature for the PCMs was in the range of 0.07-7.87 deg. C, and the change in latent heat of fusion was -1.0% to -27.7%, except for stearic acid between 560 and 1200 melt/freeze cycles. However, the decrease in the latent heats of fusion for all the PCMs was not regular with ...

Energy Technology Data Exchange (ETDEWEB)

Heat fusion is the most common joining method for polyethylene gas distribution piping. Butt fusion was studied with the intent of relating the quality of the joint to the joining conditions. A semi-empirical approach was used. The thermofluid consequences of joining conditions such as heater temperature, heating time and joining parameter were calculated using a computer model. The model was validated by instrumented tests. The strength of the joints was gauged by destructive mechanical testing. Tensile and tensile impact tests were used. Over 150 joints were fabricated using four different polyethylene resins. Most of the data are given in GRI Report No. 88/0276.2 -- Volume 2: Technical Reference on Butt Heat Fusion Joining of Polyethylene Gas Pipes. A parameter, termed the Joining Parameter, was found to characterize the joining conditions. Of the mechanical tests parameters, the impact energy was found to have the best ...

UK PubMed Central (United Kingdom)

The purpose of this paper was to inform the reader that prolonged upper airway obstruction after posterior cervical spine surgery is a possible complication for patients with metastatic tumor of upper...Full Text Available

UK PubMed Central (United Kingdom)

Hypoxia, or reduced oxygen, occurs in a variety of clinical and environmental situations. Hypoxic exposure is associated with decreased muscle mass and a concomitant reduction in exercise capacity,...Full Text Available

International Nuclear Information System (INIS)

A quantitative energy pathway comparison is made between a modern oil refinery and genetic fusion hydrogen plant supporting hybrid-electric cars powered by gasoline and hydrogen-optimized internal combustion engines, respectively, both meeting President Clinton's goal for advanced car goal of 80 mpg gasoline equivalent. The comparison shows that a fusion electric plant producing hydrogen by water electrolysis at 80% efficiency must have an electric capacity of 10 GWe to support as many hydrogen-powered hybrid cars as one modern 200,000 bbl/day-capacity oil refinery could support in gasoline-powered hybrid cars. A 10 GWe fusion electric plant capital cost is limited to 12.5 B$ to produce electricity at 2.3 cents/kWehr, and hydrogen production by electrolysis at 8 $/GJ, for equal consumer fuel cost per passenger mile as in the oil-gasoline-hybrid pathway.

International Nuclear Information System (INIS)

Through the innovative design of a novel end plug scheme employing octopole MHD stabilization, the authors present the conceptual design of ''MINIMARS'', a small commercial fusion reactor based on the tandem mirror principle. The current baseline for MINIMARS has a net electric output of 600 MWe and they have configured the design for short construction times, factory-built modules, inherently safe blanket systems, and multiplexing in station sizes of #approx =# 600-2400 MWe. They demonstrate that the compact octopole end cell provides a number of advantages over the more conventional quadrupole (yin-yang) end cell encountered in the MARS tandem mirror reactor study, and enables ignition to be achieved with much shorter central cell lengths. Accordingly, being economic in small sizes, MINIMARS provides an attractive alternative to the more conventional larger conceptual fusion reactors encountered to date, and would contribute significantly to ...

UK PubMed Central (United Kingdom)

To define the import pathway for apoiso-1-cytochrome c in vivo, the coding region for bacterial chloramphenicol acetyltransferase (CAT) or yeast copper metallothionein (CuMT) was fused to the carboxy...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The subject of FDD (fault detection and diagnosis) has gained widespread industrial interest in machine condition monitoring applications. This is mainly due to the potential advantage to be achieved from reduced maintenance costs, improved productivity and increased machine availability. This paper presents a new FDD scheme for condition machinery of an industrial steam turbine using a data fusion methodology. Fusion of a SVM (support vector machine) classifier with an ANFIS (adaptive neuro-fuzzy inference system) classifier, integrated into a common framework, is utilized to enhance the fault detection and diagnostic tasks. For this purpose, a multi-attribute data is fused into aggregated values of a single attribute by OWA (ordered weighted averaging) operators. The simulation studies indicate that the resulting fusion-based scheme outperforms the individual SVM and ANFIS systems to detect and diagnose incipient steam ...

International Nuclear Information System (INIS)

A comprehensive dataset of NDV genome sequences was evaluated using bioinformatics to characterize the evolutionary forces affecting NDV genomes. Despite evidence of recombination in most genes, only one event in the fusion gene of genotype V viruses produced evolutionarily viable progenies. The codon-associated rate of change for the six NDV proteins revealed that the highest rate of change occurred at the fusion protein. All proteins were under strong purifying (negative) selection; the fusion protein displayed the highest number of amino acids under positive selection. Regardless of the phylogenetic grouping or the level of virulence, the cleavage site motif was highly conserved implying that mutations at this site that result in changes of virulence may not be favored. The coding sequence of the fusion gene and the genomes of viruses from wild birds displayed higher yearly rates of change in ...

UK PubMed Central (United Kingdom)

Porous Nitinol (PNT) has found vast applications in the medical industry as interbody fusion devices, synthetic bone grafts, etc. However, the tendency of the PNT to corrode is anticipated to...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The newly developed techniques by the Hot Laboratory (JMTR HL) have provided for us the key information on behavior of specimens due to mechanical / physical / chemical / synergistic effects of radiation, stress and water for fission and fusion reactor environment. These techniques are focused on several topics as follows; (1) miniaturized specimen test for the development of fusion reactor materials, (2) slow strain rate tensile testing (SSRT) and crack propagation measuring tests for the study of Irradiation Assisted Stress Corrosion Cracking (IASCC) of core internals of LWR, (3) handling technique on specimens including tritium for the research and development of tritium breeders and neutron multiplier as fusion blanket materials, (4) joining method using the Tungsten Inert Gas (TIG) welding technique for re-assembling of capsule and re-fabrication of specimen and (5) nondestructive evaluation using ultrasonic wave and ...

UK PubMed Central (United Kingdom)

Mechanical forces can regulate various functions in living cells. The cytoskeleton is a crucial element for the transduction of forces in cell-internal signals and subsequent biological responses. Accordingly,...Full Text Available

International Nuclear Information System (INIS)

A conceptual fusion synfuel production system has been developed with the unique features of: (1) a fusion blanket producing high-temperature (1250"0C) process heat, and (2) the GA sulfur-iodine thermochemical cycle. The system incorporates a two-zone blanket which achieves a tritium breeding ratio of 1.1 while delivering a high fraction (30%) of the fusion heat at high temperatures (1250"0C). The multiple barriers to tritium permeation in the blanket design permit the hydrogen product to meet 10CFR20 regulatory requirements without stringent requirements on the tritium recovery systems. A ceramic heat exchanger, incorporating SiC tubes and headers to contain the process stream and a cooled, Inconel 718 pressure shell to contain the helium, was designed for transferring the heat from the high-temperature coolant to the process. A good heat-line match of the blanket heatsource temperature distribution to the requirements of ...

Energy Technology Data Exchange (ETDEWEB)

This paper describes a concept for a current drive system based on negative ions with beam energy > 1 MeV. Preliminary physics calculations show that the core current necessary for stability enhancement can best be achieved by beams with energy ranging from 1 to 4 MeV. Further study and experiments will better define the optimum energy. Work under way at Oak Ridge National Laboratory (ORNL) and at collaborating institutes in Canada and the Federal Republic of Germany is defining a system, its elements, a configuration and operational scenarios deemed appropriate for such devices as ITER and other future steady-state tokamaks, and the requisite research and development to provide such a system. 7 refs., 2 figs.

Energy Technology Data Exchange (ETDEWEB)

A study on development of magnetic drive packless valves for commercial purpose showed the results as follows; 1. Study on the radial rays effecting to the permanent magnets -Measurement of the strength of Nd-magnets according to irradiation of radial rays. 2. Effects of temperature on the magnetic driving device -Temperature dependency of the Nd-casting magnets. -Effects of temperature on the heat releasing fins of high-temperature valve. 3. Optimization of torque -Arranging method of permanent magnets -Measuring method and results of torque. 4. Design, manufacture and test for the pressure-resisting structure of magnetic power transmitting device -Calculation and design for the flat circular plates under pressure of the magnetic power transmitting device -Design, manufacture and test for the pressure-resisting ...

Energy Technology Data Exchange (ETDEWEB)

Tests have recently been performed at Fermilab in order to measure the energy losses due to eddy currents and iron and superconductor magnetization. These measurements were performed on six 1.5m long model magnets and eight 15m long full scale collider dipole magnets. AC losses were measured as a function of ramp rate using sawtooth ramps from 500, to 5000 Amps for both types of magnets, while bipolar studies were additionally performed on some of the short magnets. The measured magnet voltage and current for a complete cycle are digitally integrated to yield the energy loss per cycle. Measurement reproducibility is typically 5%, with good agreement between long magnet measurements and extrapolations from short magnet measurement results. Magnetization loss measurements among similar ...

Energy Technology Data Exchange (ETDEWEB)

Heat-of-fusion storage materials for low temperature latent heat storage in the temperature range 0-120 C are reviewed. Organic and inorganic heat storage materials classified as paraffins, fatty acids, inorganic salt hydrates and eutectic compounds are considered. The melting and freezing behavior of the various substances is investigated using the techniques of Thermal Analysis and Differential Scanning Calorimetry. The importance of thermal cycling tests for establishing the long-term stability of the storage materials is discussed. Finally, some data pertaining to the corrosion compatibility of heat-of-fusion substances with conventional materials of construction is presented.

Energy Technology Data Exchange (ETDEWEB)

The Joint European Torus (JET) fusion machine is the only device capable of operation with tritium (as fuel) and Be (as plasma facing component), what makes it best suited to study ITER relevant issues. A large variety of activities are performed within the JET Fusion Technology Task Force. In this paper, some topics such as erosion/deposition and material transport, flakes characterization and detritiation techniques are highlighted. Recent results obtained using a pumping cryo-panel and on plasma facing component characterisation are given. Finally, issues that will be addressed in the forthcoming JET work-programme are presented, such as a beryllium main wall for JET and in-situ laser detritiation. (authors)

Energy Technology Data Exchange (ETDEWEB)

Negative ion based neutral beam injector is one of the most attractive heating system in future fusion reactors. In realizing the system, the crucial device which has to be developed is a high intensity negative ion source. Significant progress has been made on the negative ion source in these years. Among them, a few ampere negative ion beam were produced stably, while the divergence of negative ion beams becomes to be as low as < 10 mrad. We consider these results are demonstrating the potential of the negative ion source for the heating device in future reactors.

Energy Technology Data Exchange (ETDEWEB)

One example of basic and applied research at LLNL that has produced major, highly visible scientific and engineering advances has been the research related to controlled fusion energy. Continuing experimentation at LLNL and elsewhere is likely to demonstrate that fusion is a viable, inexhaustible alternative source of energy. Having conducted major fusion energy experiments for over 30 years at LLNL, it scientists and engineers recognized the enormous challenges that lay ahead in this important endeavor. To be successful, it was clear that collaborative efforts with universities, private industry, and other national laboratories would need to be greatly expanded. Along with invention and scientific discovery would come the challenge of transferring the myriad of new technologies from the laboratories to the private sector for commercialization of the fusion energy process and the application of related ...

Science.gov (United States)

PMID:10860471

International Nuclear Information System (INIS)

Three different magnetic regimes; aerial, surface and buried; each with three different forces, have been used to investigate their effects on the water contents and photosynthetic pigments of sweet basil plants (Ocimum basilicum L.). Two groups of sweet basil seeds, Ocimum basilicum L. have been cultivated, one under normal conditions and the second has been subdivided into three portion (aerial, surface and buried) to examine the effect of different magnetic forces coming from the three directions on the resulted plants. At all directions of magnets, water contents have been significantly affected by the magnetic forces. Chlorophyll A and carotene contents have been affected, as well, according to the three magnetic forces coming from soil surface regime only. Chlorophyll B did not significantly affected by differences magnetic forces in the three regimes, but ...

KoreaScience (Korea)

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KoreaScience (Korea)

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KoreaScience (Korea)

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UK PubMed Central (United Kingdom)