Energy Technology Data Exchange (ETDEWEB)

Ultra High Vacuum (UHV) test setup for electron gun testing has been developed. The development of next generation light sources and accelerators require development of klystron as a radio frequency power source, and in turn electron gun. This UHV electron gun test setup can be used to test the electron guns ranging from high average current, quasi-continuous wave to high peak current, single pulse etc. An electron gun has been designed, fabricated, assembled and tested for insulation up to 80 kV under the programme to develop high power klystron for future accelerators. Further testing includes the electron emission parameters characterization of the cathode, as it determines the development of a reliable and efficient electron gun with high electron emission current and high life time as well. This needs a clean ultra high vacuum to study these parameters particularly at high emission current. The ...

International Nuclear Information System (INIS)

Focussed ion beam (FIB) technology has the advantage of being a maskless process compatible with UHV processing. This makes it attractive for use in in situ processing and has been applied to the fabrication of various mesoscopic structures. The present paper reviews these results whilst putting emphasis on in situ processing by a combined FIB and molecular beam epitaxy system. The typical performance of present FIB systems is also presented. In order to utilize the potential advantages of FIB processing, reduction of damage and improvement of throughput are important, and much effort has been devoted to developing processing techniques which require a reduced dose. The importance of low-energy FIB is discussed. (author).

International Nuclear Information System (INIS)

The current--density profile of a focused ion beam (FIB) has a central peak accompanied by broader ''wings'' that, while unimportant in lithographic applications, can lead to unwanted effects during an implantation operation. The origin of the wings, and hence the best way to minimize them, is not clear and needs further study. We have measured the line profiles of several of the ions available in our FIB machine as a function of a number of variables, under ultrahigh vacuum (UHV) conditions. No effects are observed from changes in emission current or deliberate defocusing of the objective lens. There are some changes with beam aperture and/or current, but the biggest differences seem to be associated with a change of source type and hence, possibly, with a change in the source/extractor configuration or in the alloy and the emission process. The wing amplitudes are appreciably lower than many previously observed, and their profiles, at least ...

CERN Document Server

Introduction to electromagnetic compatibility

Energy Technology Data Exchange (ETDEWEB)

The use of the focused ion beam (FIB) systems has increased to a high level in recent years. The imaging, milling, and deposition capabilities of the FIB make it the ideal instrument for e.g., site-specific failure analysis, specimen preparation and nano-machining. Ion channelling contrast allows for selective imaging of polycrystalline and polyphase microstructures. In addition, the FIB and CrossBeam registered instruments are unique stand-alone analytical tools. Their vast capabilities have enabled numerous applications into the semiconductor and materials sciences applications. These integrated CrossBeam registered Tools enable the observation and direct control of the FIB operation in real time. In addition to the improved accuracy and resolution the electron beam adds analytical capabilities as STEM, EDS and EBSP to the instruments. To ensure a safe and reliable operation of the instrument, a dedicated vacuum system is needed. This type of instrument combines ...

International Nuclear Information System (INIS)

We present an approach for fabrication of intentionally positioned epitaxial InAs QDs in a micron sized light emitting diode. For site-selective growth, a combination of molecular beam epitaxy (MBE) and focused ion beam (FIB) implantation technology in an all-ultra-high-vacuum (UHV) setup has been employed. Single dot occupancy of almost 55 % on FIB patterned nano-depressions was successfully achieved. Thereafter, carrier injection and subsequent radiative recombination from the positioned InAs/GaAs self-assembled QDs was investigated by embedding these QDs in the intrinsic part of a GaAs-based micron sized p-i-n junction device. Few or single dot are expected to be electrically addressed in these devices. We report results from electroluminescence (EL) measurement which proves the single dot characteristics of our device. The EL spectra consist of sharp emission lines and their dependence on injection current shows linear behavior for exciton ...

Energy Technology Data Exchange (ETDEWEB)

TNF-doped Mylar is a new radiation-hard dielectric that has recently been qualified as a viable substitute for Mylar in capacitors. The advantage of TNF-doped Mylar is that it satisfies both the nuclear safety and radiation hardness requirements of weapons. Mylar is not radiation-hard. Aging and compatibility studies were carried out to insure that (1) TNF does not diffuse from the film during fabrication of the capacitor or during storage; and (2) there are no compatibility problems with aluminum foil (the conductor) or Fluorinert (the secondary dielectric). Losses of TNF were barely detectable during the vacuum bakes used in fabricating capacitors or during accelerated aging tests carried out below T{sub g} (70C) over a two year period in air. In other accelerated tests, no compatibility problems were detected with aluminum or Fluorinert. TNF-doped Mylar is now being used in the MC-4109 capacitor that ...

CERN Document Server

General relativity postulates the Minkowski space-time to be the standard flat geometry against which we compare all curved space-times and the gravitational ground state where particles, quantum fields and their vacuum states are primarily conceived. On the other hand, experimental evidences show that there exists a non-zero cosmological constant, which implies in a deSitter space-time, not compatible with the assumed Minkowski structure. Such inconsistency is shown to be a consequence of the lack of a application independent curvature standard in Riemann's geometry, leading eventually to the cosmological constant problem in general relativity. We show how the curvature standard in Riemann's geometry can be fixed by Nash's theorem on locally embedded Riemannian geometries, which imply in the existence of extra dimensions. The resulting gravitational theory is more general than general relativity, similar to brane-world gravity, but where the ...

CERN Document Server

In order to produce a low energy effective field theory from a string model, it is necessary to specify a vacuum state. In order that this vacuum be supersymmetric, it is well known that all field expectation values must be along so-called flat directions, leaving the F- and D-terms of the scalar potential to be zero. The situation becomes particularly interesting when one attempts to realize such directions while assigning VEVS to fields transforming under non-Abelian representations of the gauge group. Since the expectation value is now shared among multiple components of a field, satisfaction of flatness becomes an inherently geometrical problem in the group space. Furthermore, the possibility emerges that a single seemingly dangerous F-term might experience a self-cancellation among its components. The hope exists that the geometric language can provide an intuitive and immediate recognition of when the D and F conditions are simultaneously ...

Energy Technology Data Exchange (ETDEWEB)

Nanoimprinting is a fast-growing technique for nanoscale patterning. One of the remaining issues in nanoimprinting is the removal of the residual layer after nanoimprinting. Traditionally the residual layer is removed by an oxygen reactive-ion etching (RIE) step. The need for a vacuum environment and dedicated equipment in this step lowers the throughput and increases the cost of the nanoimprinting process. It also prevents the possibility of patterning isolated functional polymers because oxygen RIE destroys the functional materials. In this work, novel nanoimprinting schemes are developed to nondestructively remove the residual layer in thermal nanoimprinting by solvent developing and dewetting. Combined with a transfer-bonding technique, three-dimensional polymer scaffolds are achieved. The techniques developed here eliminate the RIE step in thermal nanoimprinting and are compatible with roller nanoimprinting for large-scale patterning of ...

Energy Technology Data Exchange (ETDEWEB)

A carbon-bonded carbon fiber (CBCF) insulation developed for a radioisotope heat source is made from chopped rayon fiber about 10 ..mu..m in diameter and 250 ..mu..m long, which is carbonized and bonded with phenolic resin particles. The CBCF is an excellent lightweight insulating material with a nominal density of 0.2 Mg/m/sup 3/ and a thermal conductivity of 0.24 W/(m-K) in vacuum at 2000/sup 0/C. Several attributes that make CBCF particularly suitable for the heat source application have been identified. These include light weight, low thermal conductivity, chemical compatibility, and high-temperature capabilities. The mechanical strength of CBCF insulation is satisfactory for the application. The basic fabrication technique was refined to eliminate undesirable large pores and cracks often present in materials fabricated by earlier techniques. Also, processing was scaled up to increase the fabrication rate by a factor of 10. The specific ...

Energy Technology Data Exchange (ETDEWEB)

The General-Purpose Heat Source (GPHS), an improved radioisotope heat source, employs a unique thermal insulation material, carbon-bonded carbon fiber (CBCF), to protect the fuel capsule and to help achieve the highest possible specific power. The CBCF insulation is made from chopped rayon fiber about 10 ..mu..m in diameter and 250 ..mu..m long, which is carbonized and bonded with phenolic resin particles. The CBCF shapes, both tubes and plates, are formed in a multiple molding facility by vacuum molding a water slurry of the carbonized chopped-rayon fiber (54 wt %) and phenolic resin (46 wt %). The molded shapes are subsequently dried and cured. Final carbonization of the resin is at 1600/sup 0/C. Machining to close tolerances (+-0.08 mm) is accomplished by conventional tooling and fixturing. The resulting material is an excellent lightweight insulation with a nominal density of 0.2 Mg/m/sup 3/ and a thermal conductivity of 0.24 W(m.K) in ...

KoreaScience (Korea)

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KoreaScience (Korea)

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International Nuclear Information System (INIS)

A study of the thin gold film growth, during the deposition on glass substrate under UHV conditions at low temperatures, is presented. The complementary methods, the atomic force microscopy and grazing incidence x-ray reflectometry, are used for the research. It is shown that due to variation of the time of deposition from 2 to 50 min different kinds of thin Au films nanostructures are obtained: from discontinuous films consisting of isolated islands, via formation of the chains of islands, up to continuous films. (author)

Energy Technology Data Exchange (ETDEWEB)

Hamiltonian light-front dynamics of quantum fields may provide a useful approach to systematic nonperturbative approximations to quantum field theories. The authors investigate inequivalent Hilbert-space representations of the light-front field algebra in which the stability group of the light front is implemented by unitary transformations. The Hilbert space representation of states is generated by the operator algebra from the vacuum state. There is a large class of vacuum states besides the Fock vacuum which meets all the invariance requirements. The light-front Hamiltonian must annihilate the vacuum and have a positive spectrum. Relations are exhibited of the Hamiltonian to the nontrivial vacuum structure. 30 refs.

International Nuclear Information System (INIS)

This document provides the detailed design requirements for the Spent Nuclear Fuel Project Cold Vacuum Drying Facility. Process, safety, and quality assurance requirements and interfaces are specified.

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

International Nuclear Information System (INIS)

Purpose: To enable the use of a vacuum container under a relatively high temperature or a high level radioactive dose. Constitution: Vacuum sealing materials for use in a vacuum container are made of resins such as polyimide and polyamide. The sealing materials are joined to the both surfaces of a plate-like insulator by means of adhesives or sealants, or the sealing materials are joined between two plate-like insulators by means of adhesives or sealants. They are situated within grooves of both of flanges, which are clamped tightly by insulation bolt and nut. Since the vacuum sealing materials are joined to the insulator by means of the adhesives or sealants, the reliability of the vacuum sealing can be improved without impairing the electrical insulation. The resin of the vacuum sealing material can be used for the radiation dose up to 10"8 rad, temperature up ...

Science.gov (United States)

Astron. J., 82, 890-901, doi:10.1086/112143. Ghil, M., B. Shkoller, and V. Yangarber, 1977: A balanced diagnostic system compatible with a barotropic prognostic model....

Science.gov (United States)

vehicles including the H2-A rocket and the space shuttle. .... The vacuum can's main function is to provide a high vacuum so that the science experiment and its sensors ... EMI-shielded power conversion from the incoming ISS power supply. 4. ...

Science.gov (United States)

Investigation of memory effects in air at 0.7 mbar pressure in the presence of vacuum electrical breakdown mechanism has been performed in this paper. The memory effect has been followed using the time delay method.

Science.gov (United States)

... more than expected in developing a unique bond strength measurement protocol that is important for a wide range of bond strength measurements. ...

Science.gov (United States)

... The nature of the vacuum breakdown mechanism presents just such a problem and the relative significance or total absence of several processes ...

International Nuclear Information System (INIS)

... bismuth chlorides bismuth 207 cadmium chlorides efficiency evaporation high

International Nuclear Information System (INIS)

This study describes the mechanical compatibility of the direct use of spent pressurized water reactor (PWR) fuel in Canada deuterium uranium (CANDU) reactors (DUPIC) fuel, when it is loaded into a CANDU reactor. The mechanical compatibility can be assessed for the fuel management, primary heat transport system, fuel channel, and the fuel handling system in the reactor core by both the experimental and analytic methods. Because the physical dimensions of the DUPIC fuel bundle adopt the CANDU flexible (CANFLEX) fuel bundle design which has already been demonstrated for a commercial use in CANDU reactors, the experimental compatibility analyses focused on the generation of material property data and the irradiation tests of the DUPIC fuel, which are used for the computational analysis. The intermediate results of the mechanical compatibility analysis have shown that the integrity of the DUPIC fuel is ...

International Nuclear Information System (INIS)

Development of a front end system for a high energy proton accelerator is in progress at Korea Atomic Energy Research Institute (KAERI) for basic science and industrial applications. The proper vacuum components has been installed and operated successfully between ion source and RFQ. The reliable operation of the accelerator has been completed at vacuum system in the high and ultra high vacuum range under operating conditions. Proper control system for the vacuum instruments, based on PC operated by Windows, has been designed and constructed by control group at PAL. As PC operated by windows with inherent instability does not proper, embedded system can be replaced for reliable operation system, such as VME system operated by vxWorks.

Energy Technology Data Exchange (ETDEWEB)

Alloy 800 is an austenitic Fe-Ni-Cr steel containing relatively minor but important amounts of carbon, aluminium and titanium. Special grades of alloy 800 known as 800H, 800HT and 800LC differ in the concentrations of these elements. In addition to these industrial specifications, further melts were prepared containing phosphorous or sulphur. Using a radioactive tracer method the bulk and grain-boundary diffusion of {sup 59}Fe was investigated in these alloys in the temperature range 800 to 1000 C. For evaluation of the diffusion profiles the approximation of Suzuoka was used, which considers the depletion of the tracer on the surface. By autoradiography it was confirmed that such depletion occurs. In alloy 800H the activation energy of grain-boundary diffusion of {sup 59}Fe was found to be (209{+-}17) kJ/mol; dissolved elements, especially phosphorous, increase the activation energy. The same materials - aged at 800 C for 100 h - were used for creep experiments at 800 C under constant ...

International Nuclear Information System (INIS)

An energy analyzer has been constructed and operated in UHV for the purpose of analyzing the energy of neutral atoms scattered from solid surfaces. The analyzer consists of a LiF single crystal located at an angle close to the normal to the sample crystal so that the diffraction pattern obtained by scanning the LiF crystal yields the energy of the scattered atoms. Two designs which have been used are described. The temperature of both sample and analyzer crystal is near 20 K and once cleaned they can be maintained in the state of initial preparation for many weeks. The sample was a (001) Cu surface in this case. Such an energy analyzer can only be used, in most cases, for He atom scattering although Ne atoms could be used if the scattered intensities were adequate. The detector developed in this study is able to detect about 2 x 10"5 atoms/s. The resolution of the spectrometer depends on the incident energy of the atom and is about 1 meV at an incident energy of 23 ...

Energy Technology Data Exchange (ETDEWEB)

Every cook knows that microwaves and metal don't mix. But scientists at the National Institute of Standards have devised a way to make them compatible. If it all pans out, hospitals may be able to sterilize medical instruments and waste in a device similar to a conventional microwave oven.

Science.gov (United States)

Ghil, M., B. Shkoller, and V. Yangarber, 1977: A balanced diagnostic system compatible with a barotropic prognostic model. M. Weather. Rev. , 105, 1223- 1238, ...

UK PubMed Central (United Kingdom)

Larvae of an anhydrobiotic insect, Polypedilum vanderplanki, accumulate very large amounts of trehalose as a compatible solute on desiccation, but the molecular mechanisms underlying...Full Text Available

Science.gov (United States)

A program was conducted to develop a pop-up artificial-foliage system compatible with the rural Maryland (summertime) background environment. The result of this Phase I effort was a self-expanding leaf module, a number of which are stored flat in a simple...

British Library Electronic Table of Contents (United Kingdom)

The properties of ZnO films were investigated as functions of annealing temperatures in H2/Ar and vacuum. The resistivities and mobilities of ZnO films decreased with increase of annealing temperatures in vacuum and H2/Ar ambients. However, the carrier densities of ZnO films increased with increase of annealing temperatures in vacuum and H2/Ar ambients. The resistivities of ZnO2 films annealed at 300degreeC were 2186cm and 798cm in H2/Ar and vacuum ambients, respectively. The resistivities of ZnO films annealed in vacuum and H2/Ar ambients at 600degreeC were similar with 0.040cm and 0.035cm, respectively. The hydrogen donor was more dominant than the oxygen vacancy or Zn interstitial donor in ZnO films annealed in ambient H2/Ar at low temperatures. The average optical transmission was >82%...

Energy Technology Data Exchange (ETDEWEB)

An independent chemical compatibility review of various wrapping and absorbent/padding materials was conducted to evaluate resistance to chemicals and constituents present in liquid waste from the Hanford underground tanks. These materials will be used to wrap long-length contaminated equipment when such equipment is removed from the tanks and prepared for transportation and subsequent disposal or storage. The materials studied were Cooley L18KU, Herculite, and Elephant Mat. The study concludes that these materials are appropriate for use in this application.

Energy Technology Data Exchange (ETDEWEB)

The Dental Investigation Service, USAFSAM, Brooks AFB, has outlined the need for a vacuum unit to be used in the Air Force dental clinics. The unit must be capable of effectively picking up mercury and at the same time not redistribute mercury vapors throughout the dental clinic during normal operations or mercury-spill situations. The Dental Investigation Service selected the MRS-3, Minuteman Mercury Recovery System, product of American Cleaning Equipment Corporation as the mercury vacuum to be used for T E. The USAF OEHL/ECH was requested by the Dental Investigation Service to perform the T E on the MRS-3 for possible health hazards due to exposures of mercury vapors.

CERN Document Server

We investigate the solar neutrino problem in the scenario of three generation neutrino oscillation hypothesis, taking into account other phenomenological constraints to the neutrino mixing and mass parameters.

Energy Technology Data Exchange (ETDEWEB)

A miniature x-ray source utilizing a hot filament cathode. The source has a millimeter scale size and is capable of producing broad spectrum x-ray emission over a wide range of x-ray energies. The miniature source consists of a compact vacuum tube assembly containing the hot filament cathode, an anode, a high voltage feedthru for delivering high voltage to the cathode, a getter for maintaining high vacuum, a connector for initial vacuum pump down and crimp-off, and a high voltage connection for attaching a compact high voltage cable to the high voltage feedthru. At least a portion of the vacuum tube wall is fabricated from highly x-ray transparent materials, such as sapphire, diamond, or boron nitride.

International Nuclear Information System (INIS)

A high-average power (kW) infrared (IR) free-electron laser (FEL) is currently being commissioned for the Jefferson Laboratory FEL User Facility. The IR FEL is driven by a unique superconducting rf linac which is recirculated to recover electron beam power that is not radiated in the FEL. The design and installation of the vacuum system for the FEL involved particular attention to minimizing particulate contamination which could cause problems with the superconducting acceleration cavities and the high power FEL optics. Particulate contamination levels of all vacuum components were monitored during the cleaning process using laser scattering. Cleaning, transport, and installation procedures were developed to minimize the contamination of the complete system. We will summarize a data base we compiled of particulate contamination levels of the various components installed in the FEL vacuum system.

Energy Technology Data Exchange (ETDEWEB)

Vacuum arc with cathode spots on the cold electrode is widely used as a plasma generator in a such kind of devices like metal ion sources, plasma cathode electron guns, thing films deposition facilities and others. Most vacuum arc devices utilize a high voltage discharge across an insulator surface to provide a trigger plasma which in turn initiates the main arc discharge. Operation of vacuum arc in a repetitively pulsed mode required a stable triggering system for the long time. But with a discharge across the insulators the number of stable pulses is limited by 100,000 or little bit more. The better method for vacuum arc ignition is low pressure discharge. As shown in this paper it is possible to increase the lifetime of the ignition system in 10 times at least, but negative characteristic of this system is a relatively high pressure (about 0.1 mtorr). In some kinds of vacuum arc ...

Energy Technology Data Exchange (ETDEWEB)

The Technical Safety Requirements (TSRs) for the Cold Vacuum Drying Facility define acceptable conditions, safe boundaries, bases thereof, and management or administrative controls required to ensure safe operation. Controls required for public safety, significant defense-in-depth, significant worker safety, and for maintaining radiological and toxicological consequences below risk evaluation guidelines are included.

Energy Technology Data Exchange (ETDEWEB)

An algebraic formulation of the electromagnetic field in which various quantization procedures can be described was chosen to discuss perturbation calculations. It is shown that the Feynman rules and the second order calculation of the self-energy of the electron can be developed on the basis of the Fermi method of quantization. The algebraic approach clarifies the problems in defining the vacuum and other states which are associated with calculations in terms of field algebra operators. It is demonstrated that the vacuum state defined on the field algebra by Schwinger leads to incorrect results in the self-energy calculation.

International Nuclear Information System (INIS)

We analyze the stability of the structure equations of the vacuum in the brane world models, by using both the linear (Lyapunov) stability analysis, and the Jacobi stability analysis, the Kosambi-Cartan-Chern theory. In the brane world models the four-dimensional effective Einstein equations acquire extra terms, called dark radiation and dark pressure, respectively, which arise from the embedding of the three-brane in the bulk. Generally, the spherically symmetric vacuum solutions of the brane gravitational field equations have properties quite distinct as compared to the standard black hole solutions of general relativity. We close the structure equations by assuming a simple linear equation of state for the dark pressure. In this case the vacuum is Jacobi stable only for a small range of values of the proportionality constant relating the dark pressure and the dark radiation. The unstable trajectories on the brane behave ...

Energy Technology Data Exchange (ETDEWEB)

To investigate the usefulness of a newly developed magnetic resonance (MR) image-guided surgical robotic system for minimally invasive laparoscopic surgery. The system consists of MR image guidance [interactive scan control (ISC) imaging, three-dimensional (3-D) navigation, and preoperative planning], an MR-compatible operating table, and an MR-compatible master-slave surgical manipulator that can enter the MR gantry. Using this system, we performed in vivo experiments with MR image-guided laparoscopic puncture on three pigs. We used a mimic tumor made of agarose gel and with a diameter of approximately 2 cm. All procedures were successfully performed. The operator only advanced the probe along the guidance device of the manipulator, which was adjusted on the basis of the preoperative plan, and punctured the target while maintaining the operative field using robotic forceps. The position of the probe was monitored continuously with 3-D ...

CERN Document Server

The network utility maximization (NUM) problem for multi-path is a problem which is non-strictly convex and non-separable. Using Jensen's inequality, we approximate the NUM to a strictly convex and separable problem which can be solved efficiently by the dual decomposition method. After a series of approximations, the result of the approximation problem converges to the globally optimal solution of the original NUM. Moreover, because of the separable and dual-based natures of the proposed algorithm, we utilize the reverse engineering frameworks of the current TCPs to develop a series of multi-path TCPs which are totally compatible with current TCPs. The multi-path users using our protocols can run simultaneously with the single-path users using the current TCPs. The simulations of our Multi-path Reno on ns-2 show the compatibility and the fairness among multi-path and single-path users.

Energy Technology Data Exchange (ETDEWEB)

This bill was introduced into the US House of Representatives on June 7, 1991 to provide for the designation of Wetlands Stewardship Trusts. This legislation amended the Internal Revenue Code of 1986 to establish special rules for contributions of wetlands and riparian lands to Wetlands Stewardship Trusts. Key features of the bill address the following: tax treatment of donations of wetlands and riparian lands to Wetlands Stewardship Trusts; amortization of expenditures to restore wetlands and riparian lands; expenditures for restoring wetlands and riparian lands; exclusion from gross income for amounts received from compatible uses of wetlands or riparian lands; and income from compatible uses of wetlands or riparian lands.

Energy Technology Data Exchange (ETDEWEB)

Problems relating to electromagnetic compatibility and power quality were discussed, combined with a discussion of the role that consulting engineers can play in resolving them. The need for the consulting engineer to be aware of design specifications of equipment was considered essential. Similarly, the interrelationship between installations using variable speed drives, halogenous lighting systems, capacitor banks, high-voltage power lines, power transformers, etc., and the need for familiarity with the operating characteristics of different types of power systems were stressed as key ingredients to success in ascertaining events and causes of equipment failure or power system problems on the network. The main sources of disturbances, impact of voltage variations, the importance of controlling voltage imbalance, and system protection were summarized. 4 figs.

Science.gov (United States)

Plastic composites have become a large class of construction material for exterior applications. One of the main disadvantages of wood plastic composites resides in the weak adhesion between the polar and hydrophilic surface of wood and the non-polar and hydrophobic polyolefin matrix, hindering the dispersion of the flour in the polymer matrix. To improve interfacial compatibility wood flour can be pretreated with environmentally friendly methods such as cold-atmospheric pressure plasma. The objective of this work is therefore to evaluate the potential of plasma polymerization of acetylene on wood flour to improve the compatibility with polyolefins. This presentation will describe the reactor design used to modify wood flour using acetylene plasma polymerization. The optimum conditions for plasma polymerization on wood particles will also be presented. Finally preliminary results on the wood flour surface properties and use in wood plastic ...

International Nuclear Information System (INIS)

On all steam turbines operating with condensation the air leakage penetrating from the part of the plant which is under vacuum must be eliminated, in order to maintain the vacuum created by physical conditions. In order to attain effective air bleed-off, the water-steam-air mixture is conveyed via the super-cooling bundles in the condenser. In this way the steam partial pressure decreases and the air partial pressure increases at a constant condenser pressure. In this procedure the mixture is supercooled by about 4"0C compared with the saturate steam temperature appertaining to the condenser pressure. The values of volume of air leakage are the result of a year's experience on existing plant. (orig.).

CERN Document Server

One hope to solve the cosmological constant problem is to identify a symmetry principle, based on which the cosmological constant can be reduced either to zero, or to a tiny value. Here, we note that requiring that the vacuum state is Lorentz invariant significantly reduces the theoretical value of the vacuum energy density. Hence, this also reduces the discrepancy between the observed value of the cosmological constant and its theoretical expectation, down from 123 orders of magnitude to 56 orders of magnitude. We find that, at one loop level, massless particles do not yield any contribution to the cosmological constant. Another important consequence of Lorentz symmetry is stabilization of the gravitational hierarchy: the cosmological constant (divided by Newton's constant) does not run as the quartic power of the renormalization group scale, but instead only logarithmically.

British Library Electronic Table of Contents (United Kingdom)

We have measured time-resolved laser-induced incandescence of flame-generated soot under high-vacuum conditions (4.1?10?6 mbar) at an excitation wavelength of 532 nm with laser fluences spanning 0.06?0.5 J/cm2. We generated soot in an ethylene/air diffusion flame, introduced it into the vacuum system with an aerodynamic lens, heated it using a pulsed laser with a spatially homogeneous and temporally smooth laser profile, and recorded LII temporal profiles at 685 nm. At low laser fluences LII signal decay rates are slow, and LII signals persist beyond the residence time of the soot particles in the detection region. At these fluences, the temporal maximum of the LII signal increases nearly linearly with increasing laser fluence until reaching a plateau at ?0.18?J/cm2. At higher fluences, th...

CERN Document Server

We study from a critical perspective several quantum-electrodynamic phenomena commonly related to vacuum electromagnetic (EM) fluctuations in complex media. We compute the resonance-shift, the spontaneous emission rate, the local density of states and the van-der-Waals-Casimir pressure in a dielectric medium using a microscopic diagrammatic approach. We find, in agreement with some recent works, that these effects cannot be attributed to variations on the energy of the EM vacuum but to variations of the dielectric self-energy. This energy is the result of the interaction of the bare polarizability of the dielectric constituents with the EM fluctuations of an actually polarized vacuum. We have found an exact expression for the spectrum of these fluctuations in a statistically homogeneous dielectric. Those fluctuations turn out to be different to the ones of normal radiative modes. It is the latter that carry the ...

International Nuclear Information System (INIS)

A scheme is presented for the generation of entangled states for two cavity mirrors. In the scheme each mirror initially in a vacuum state interacts with a weak coherent field, resulting in a photon-number dependent kick. The detection of a photon leaking from the cavities collapses the two mirrors to an entangled state.

International Nuclear Information System (INIS)

A Monte Carlo simulation of the vacuum Bianchi type-IX (mixmaster) cosmology yields a significant correlation between large universe volume and high anisotropy. An analog of the model's chaotic classical behavior is seen in the break up of the universe wave function at large volume into fingers in the corners of the minisuperspace anisotropy potential.

Science.gov (United States)

Spontaneous radiation by an atom in a Rydberg state is inhibited by use of parallel conducting planes to eliminate the vacuum modes at the transition frequency. Spontaneous radiation emission is observed to turn off abruptly at the cutoff frequency of the waveguidelike structure, and the natural lifetime is measured to increase by a factor of at least 20.

Science.gov (United States)

Bulk monomer MMA was impregnated into simul, a fuel wood of Bangladesh, under vacuum and under normal temperature and pressure conditions in order to compare the mode of impregnation and its effect on various characteristic parameters of wood plastic composites. Methanol (MeOH) was used as the swelling solvent with methylmethacrylate (MMA) at MMA: MeOH = 70:30, v/v. Impregnation of the bulk monomer was very high under vacuum compared to that at normal condition; but the difference of grafting of MMA to the wood cellulose under these two impregnating conditions was much lower as compared to that of the uptakes of impregnating solution MMA + MeOH under these two modes of impregnation. Incorporation of additives to MMA + MeOH has substantially enhanced grafting, tensile strength, bending strength and compression strength of the composite to such an extent that there is virtually very little difference between vacuum ...

Energy Technology Data Exchange (ETDEWEB)

Plasma surface interactions in tokamaks are known to create significant quantities of dust, which settles onto surfaces and accumulates in the vacuum vessel. In ITER, a loss of vacuum accident may result in the release of dust which will be radioactive and/or toxic, and provides increased surface area for chemical reactions or dust explosion. A new method of analysis has been developed for modeling dust resuspension and transport in loss of vacuum accidents. The aerosol dynamic equation is solved via the user defined scalar (UDS) capability in the commercial CFD code Fluent. Fluent solves up to 50 generic transport equations for user defined scalars, and allows customization of terms in these equations through user defined functions (UDF). This allows calculation of diffusion coefficients based on local flow properties, inclusion of body forces such as gravity and thermophoresis in the convection term, and user defined ...

Science.gov (United States)

The evolution of the Doublet III neutral beam armor is followed from the initial design of a radiation cooled metallic tile to the present actively cooled graphite design. Results of the thermal and stress analyses that dictated the present design are reviewed.

Energy Technology Data Exchange (ETDEWEB)

We provide an example in which the Heisenberg and the Schroedinger pictures of quantum mechanics give different results, thus confirming the statement of P.A.M. Dirac that the two pictures may lead to inequivalent results. We consider a one-dimensional nonrelativistic charged harmonic oscillator (frequency {omega}{sub 0} and mass m), and take into account the action of the radiation reaction and the vacuum electromagnetic forces on the charged oscillator. We show that the Heisenberg picture gives the correct value, {Dirac_h}{omega}{sub 0}/2, for the ground state energy of the harmonic oscillator in both cases of classical and quantized vacuum fields. In the case of the Schroedinger picture, considering classical vacuum fields, and using a simple calculation for the classical radiation reaction force that is valid in the limit of large mass (mc{sup 2} >> {Dirac_h}{omega}{sub 0}), we obtain the value ...

CERN Document Server

A four-block collimator installed on a control table for positioning the alignment reference marks. Designed for use with SPS secondary beams, the collimator operates under vacuum conditions. See Annual Report 1976 p. 121 and photo 7701014.

Energy Technology Data Exchange (ETDEWEB)

The Minami-Iwaki trunk line now under construction by Tokyo Electric Power Company is an UHV transmission line which covers 130km from the central region of the Abukuma highlands, Fukushima Prefecture, through the northern ridge of the Kanto Plain to Imaichi City, Tochigi Prefecture and has 235 steel towers. About 30% of the ground along the above route is mainly layers of sand and gravel. Accordingly it has become urgent to design rationally the pile foundations in the sand and gravel layers. Hence the company has studied an estimation method of the ultimate bearing power of cast-in-place piles penetrating the sand and gravel layers and the displacement of pile heads. In this report, the result of the above study is described. The company has so far used the equations in accordance to the Meyerhof equations for the estimations of the ultimate bearing power and this time, this equations have been examined for its application to the sand and gravel layers, and for ...

Energy Technology Data Exchange (ETDEWEB)

The vacuum polarization splitting of the M-shell states in muonic hydrogen can have a profound influence on the muonit de-excitation cascade in deuterium and tritium targets. The cascade also shows sensitive dependence on the precise rate of transfer processes between certain excited muonic deuterium and tritium atoms. Recent experimental data, where a much greater population of the (d..mu..) qs state (1/sub 1//sub //sub s/) was found than previously predicted, can be explained if the transfer rates from the (d..mu..) M-shell are assumed to be strongly suppressed.

Energy Technology Data Exchange (ETDEWEB)

The fatigue properties of EP539LM alloy with an Al-Nb-Si fused slurry coating and a Co-Cr-Al-Y electron-beam coating are investigated experimentally in vacuum and in air at 900 C. It is found that the protective coatings reduce the fatigue life of the specimens both in vacuum and in air, with the electron-beam coating affecting the fatigue life of the alloy to a lesser degree than the fused slurry coating. The negative effect of the coatings on the fatigue life of the alloy is attributed largely to the properties of the coating material. 7 references.

International Nuclear Information System (INIS)

The nitric acid solution dissolving nuclear fuel material is transferred with the three way valve called VCV (VCV: vide-casse-vide in Fr.) using vacuum in the Tokai Reprocessing Plant. The initial VCV was not reliable because it had broken with in 1 or 2 years. The cause of failure was damage of the plastic diaphragms in the moving parts. Then, the new VCV valve with stainless-steel bellows was developed. There is no failure in moving parts in 20 years, therefore reliability is significantly improved. (author)

CERN Document Server

If quantum fields exist in extra compact dimensions, they will give rise to a quantum vacuum or Casimir energy. That vacuum energy will manifest itself as a cosmological constant. The fact that supernova and cosmic microwave background data indicate that the cosmological constant is of the same order as the critical mass density to close the universe supplies a lower bound on the size of the extra dimensions. Recent laboratory constraints on deviations from Newton's law place an upper limit. The allowed region is so small as to suggest that either extra compact dimensions do not exist, or their properties are about to be tightly constrained by experimental data.

Energy Technology Data Exchange (ETDEWEB)

We consider the dynamics toward the initial singularity of Bianchi type IX vacuum and orthogonal perfect fluid models with a linear equation of state. The 'Bianchi type IX attractor theorem' states that the past asymptotic behavior of generic type IX solutions is governed by Bianchi type I and II vacuum states (Mixmaster attractor). We give a comparatively short and self-contained new proof of this theorem. The proof we give is interesting in itself, but more importantly it illustrates and emphasizes that type IX is special, and to some extent misleading when one considers the broader context of generic models without symmetries.

CERN Document Server

We consider the dynamics towards the initial singularity of Bianchi type IX vacuum and orthogonal perfect fluid models with a linear equation of state. The `Bianchi type IX attractor theorem' states that the past asymptotic behavior of generic type IX solutions is governed by Bianchi type I and II vacuum states (Mixmaster attractor). We give a comparatively short and self-contained new proof of this theorem. The proof we give is interesting in itself, but more importantly it illustrates and emphasizes that type IX is special, and to some extent misleading when one considers the broader context of generic models without symmetries.

Energy Technology Data Exchange (ETDEWEB)

As waste disposal methods and long-term precautionary care of the environment are closely related, disposal of non-avoidable and intractable residual products is to be viewed primarily from a safety angle. Also, thermal processes airm mainly at treatment, not utilization. 'Safety' in this context addresses both the environmental compatibility of the products and the process itself. In other words, only mature techniques (i.e., safe, proven ones) are employed. (orig.)

International Nuclear Information System (INIS)

Soil placed over any sealant/barrier system can provide a protective mantle if the soil is not lost by erosion. Vegetation is an attractive choice for controlling erosion because it can provide an economical self-renewing cover that serves to reduce erosion by both wind and water. The objective of this research and development effort is to select and test vegetation strategies, including the choice of species and methods for revegetation that are compatible with sealant/barrier systems and are suited to soils and climates at inactive uranium mill tailings sites.

Energy Technology Data Exchange (ETDEWEB)

HEW is operating one of the biggest district heating networks of the Federal Republic of Germany. The paper discusses a number of projects which in recent years have been engaged in extensive air pollution abatement measures to make district heating an environmentally compatible energy source. Emphasis is placed on the hot gas cleanup system of block 2 of the harbor power plant. The system is the first of its kind to have realized an SCR system connected with the desulfurization system for industrial denitrification purposes.

Energy Technology Data Exchange (ETDEWEB)

Qualifying corrosion inhibitors for use in high velocity multiphase flowlines in arctic or subsea environments is discussed. The tests include high velocity flow loop corrosion tests, pumpability through 0.125 (0.318 cm) inch capillary at low temperatures, compatibility with Nylon 11, emulsion tendency testing, and partitioning characteristics. Laboratory and field data show the importance for using the above criteria for inhibitor selection.

International Nuclear Information System (INIS)

Computed tomography was performed on 5 patients with chronic cerebral paragonimiasis. CT showed solitary or multiple, amorphous, round, or oval calcifications, and ventricular enlargement in all 5 cases. A large low-density area is also found in 4 of the 5 cases. These CT findings are compatible with previously reported findings of simple X-ray films of the skull, pneumoencephalography, and pathological studies. (author).

CERN Document Server

An S-brane solution with two non-composite electric branes and a set of l scalar fields is considered. The intersection rule for branes corresponds to the Lie algebra A_2. The solution contains five factor spaces with the fifth one interpreted as ``our'' 3-dimensional space. It is shown that there exists a time interval where accelerating expansion of ``our'' 3-dimensional space is compatible with small enough value of effective gravitational ``constant'' variation.

Energy Technology Data Exchange (ETDEWEB)

The simulation of the Auxiliary Charcoal Bed (ACB) Vacuum System was performed to evaluate the original vacuum system design, detect and identify design deficiencies, investigate the effects of proposed corrections on system performance, and generally aid in refining the system design before construction and mockup testing. The simulation was performed by using the Advanced Continuous Simulation Language (ACSL). The vacuum system design goals are to provide approximately 20 SCFM of both booster gas and purge gas through the system and maintain a flow of approximately 40 SCFM with a velocity of 50 to 75 f/sec at the entrance to the cyclone separator. The model results showed that the original system design was incapable of meeting the system performance goals. Further simulations showed that the following modifications to the original vacuum system design were required to make the system performance ...

Energy Technology Data Exchange (ETDEWEB)

Vanadium alloys exhibit important advantages as a candidate structural material for fusion first wall/blanket applications. These advantages include fabricability, favorable safety and environmental features, high temperature and high wall load capability, and long lifetime under irradiation. Vanadium alloys with (3-5)% chromium and (3-5)% titanium appear to offer the best combination of properties for first wall/blanket applications. A V-4Cr-4Ti alloy is recommended as the reference composition for the ITER application. This report provides a summary of the R&D conducted during 1994 in support of the ITER Engineering Design Activity. Progress is reported for Vanadium Alloy Production, Welding, Physical Properties, Baseline Mechanical Properties, Corrosion/Compatibility, Neutron Irradiation Effects, Helium Transmutation Effects on Irradiated Alloys, and the Status of Irradiation Experiments. Separate abstracts have been prepared for individual reports from this ...

International Nuclear Information System (INIS)

Materials Scientists need information on the kinetics of the microstructural evolution processes that determine the finished microstructure, and hence the properties, of any material. E.g. recrystallisation, grain growth and phase changes. Such kinetic information requires reliable discrimination of differently oriented crystallites and/or different crystal phases coupled with useful spatial resolution and temporal resolution (i.e. high frame rates). These imaging results must be realised from a hot and changing specimen, in an instrument that is compatible with that hot specimen and with a practical specimen heater. Focused Ion Beams (FIB) offer strong contrast between crystallites and phases, and hence offer the ability to discriminate between these features even while imaging at fast frame rates, however their compatibility with hot specimens was unproven. Here we report results from a novel combination of FIB with an in-situ heating stage, ...

CERN Document Server

In this work we develop a new propagation model for the Galactic cosmic rays based on the GALPROP code, including contributions from dark matter annihilation. The model predicts compatible Galactic diffuse $\\gamma$ ray spectra with EGRET data in all sky regions. It also gives consistent results of the diffuse $\\gamma$ ray longitude and latitude distributions. Further the results for B/C, $^{10}$Be/$^9$Be, proton, electron and antiproton spectra are also consistent with cosmic ray measurements. In the model we have taken a universal proton spectrum throughout the Galaxy without introducing large fluctuation for the proton energy loss is negligible. The dark matter annihilation signals are `boosted' after taking the contribution from subhalos into account. Another interesting feature of the model is that it gives better description of the diffuse $\\gamma$ rays when taking the source distribution compatible with supernova remnants data, which ...

Energy Technology Data Exchange (ETDEWEB)

The motivation of this work is to develop high reflectance normal-incidence multilayer mirrors in the 8-12 nm wavelength region for applications in astronomy and extreme ultraviolet lithography. To achieve this goal, Mo/Sr and Mo/Y multilayers were studied. These multilayers were deposited with a UHV magnetron sputtering system and their reflectances were measured with synchrotron radiation. High normal-incidence reflectances of 23% at 8.8 nm, 40.8% at 9.4 nm, and 48.3% at 10.5 nm were achieved. However, the reflectance of Mo/Sr multilayers decreased rapidly after exposure to air. Attempts to use thin layers of carbon to passivate the surface of Mo/Sr multilayers were unsuccessful. Experimental results on the refractive index {tilde n} = 1-{delta} + i{beta} of yttrium and molybdenum in the 50-1300 eV energy region are reported in this work. This is the first time ever that values on the refractive index of yttrium are measured in this energy range. The absorption ...

Energy Technology Data Exchange (ETDEWEB)

We revisited the quantum Zeno paradox, which claims that a generic quantum system prepared in a state which is not an eigenstate of the Hamiltonian operator and is continuously observed never decays. Since any perfectly isolated quantum system always interact with a vacuum field, we analyze the possibility of using this fact to solve the above mentioned conceptual problem. Therefore we discuss a two-level system or qubit-Bose field interaction Hamiltonians. We consider the quantum dynamics of this two-level system, prepared in the excited state interacting with a Bose field prepared in the Poincare invariant vacuum state. Using a first-order approximation in time-dependent perturbation theory, we evaluate the probability of spontaneous decay of the two-level system driven by the vacuum field. This probability is evaluated for a finite time interval. Using the standard argument to obtain the quantum Zeno paradox, we consider ...

Energy Technology Data Exchange (ETDEWEB)

Aiming to realize ball bearings operable in a vacuum and under high temperature, silicon nitride (Si3N4) ceramic ball bearings were tested. The tested ball bearings were angular contact ball bearings composed of silicon nitride with sputtered molybdenum disulfide coating using a retainer of hot-pressed self-lubricating composite material. The time variation of the frictional torque was examined for the operations under the conditions at 500{degree}C in a vacuum at a rotational speed of 600 rpm and 50N thrust load for 5{times}10{sup 7}revolutions (1400 hours) and for 1.5{times}10{sup 8}revolutions (4200 hours). Excellent tribological performance was obtained. The ball bearings are lubricated with the molybdenum disulfide film at the initial stage of the operation and with a transfer film formed from the retainer material to the balls. In a test at 650{degree}C, low and stable frictional torque was observed up to 500 hours of operation as of the ...

Energy Technology Data Exchange (ETDEWEB)

The decays of charmed mesons into two body nonleptonic final states are investigated. Weak interaction amplitudes of interest in these decays are extracted from lattice four-point correlation functions using a effective weak Hamiltonian including effects to order G{sub f} in the weak interactions yet containing effects to all orders in the strong interactions. The lattice calculation allows a quantitative examination of non-spectator processes in charm decays helping to elucidate the role of effects such as color coherence, final state interactions and the importance of the so called weak annihilation process. For D {yields} K{pi}, we find that the non-spectator weak annihilation diagram is not small, and we interpret this as evidence for large final state interactions. Moreover, there is indications of a resonance in the isospin {1/2} channel to which the weak annihilation process contributes exclusively. Findings from the lattice calculation are compared to results from the continuum ...

CERN Document Server

An electroweak model with running coupling constants described by an energy dependent entire function is utraviolet complete and avoids unitarity violations for energies above 1 TeV. The action contains no physical scalar fields and no Higgs particle and the physical electroweak model fields are local and satisfy microcausality. The $W$ and $Z$ masses are compatible with a symmetry breaking $SU(2)_L\\times U(1)_Y \\rightarrow U(1)_{\\rm em}$, which retains a massless photon. The vertex couplings possess an energy scale $\\Lambda_W > 1$ TeV predicting scattering amplitudes that can be tested at the LHC.

International Nuclear Information System (INIS)

We compare the existing observational data on type Ia supernovae with the evolutions of the Universe predicted by a one-parameter family of tachyon models which we have introduced recently [Phys. Rev. D 69, 123512 (2004)]. Among the set of the trajectories of the model which are compatible with the data there is a consistent subset for which the Universe ends up in a new type of soft cosmological singularity dubbed big brake. This opens up yet another scenario for the future history of the Universe besides the one predicted by the standard #LAMBDA#CDM model.

Energy Technology Data Exchange (ETDEWEB)

As part of our effort to develop a semicontinuous PuO/sub 2/ reduction process, we are investigating promising materials for containing a 900/sup 0/C molten CaCl/sub 2/ . CaO chlorination reaction. We want the material to contain this reaction and to be reusable. We tested candidate materials in a simulated salt (no plutonium) using anhydrous HCl as the chlorinating agent. Data are presented on the performance of 36 metals and alloys, 9 ceramics, and 3 coatings.

CERN Document Server

We investigate stability properties of indirectly damped systems of evolution equations in Hilbert spaces, under new compatibility assumptions. We prove polynomial decay for the energy of solutions and optimize our results by interpolation techniques, obtaining a full range of power-like decay rates. In particular, we give explicit estimates with respect to the initial data. We discuss several applications to hyperbolic systems with {\\em hybrid} boundary conditions, including the coupling of two wave equations subject to Dirichlet and Robin type boundary conditions, respectively.

Energy Technology Data Exchange (ETDEWEB)

On September 25, 1986, an elderly Virginia couple had their home fumigated by a local pest extermination company for the control of wood-boring insects. Two hundred and fifty pounds of sulfurylfluoride (SF), a colorless, odorless fumigant gas commonly used for this purpose, was applied in the approximately 80,000-cubic-foot home that date. Within 1 week, both husband and wife were dead. Because both deaths occurred within a short period of time and the wife's illness was compatible with toxic gas inhalation, these deaths were then thought to be related to the home fumigation.

CERN Document Server

If (S,h) is an open book with disconnected binding then we can form a new open book (S',h') by capping off one of the boundary components of S with a disk. We define a U-equivariant map on Heegaard Floer homology which sends c^+(S',h') to c^+(S,h), and we discuss various applications. In particular, we compute the 3-dimensional invariant associated to any contact structure with non-vanishing contact invariant which is compatible with a genus one open book with periodic monodromy.

International Nuclear Information System (INIS)

The diagonal and symmetric Bianchi type IX models are coupled to a homogeneous spinor field. An action for the combined fields is constructed, where the orthonormal basis used is given explicitly in terms of the metric. This allows one to vary the action with respect to the metric and the spinor fields only. Next, a Hamiltonian formulation is given, and a qualitative solution for the problem is presented. We also show that the k = +1 FRW (Friedmann--Robertson--Walker) model is not compatible with a homogeneous spinor field, while the more complicated models are.

Energy Technology Data Exchange (ETDEWEB)

The present research has been made to develop and review critically the functional requirements of the specific safety systems of CANDU such as SOS-1, SOS-2, ECCS and containment. Based on R documents for this, a systematic study was made to develop the domestic regulation statements. Also, the conventional laws are carefully reviewed to see the compatibility to CANDU. Also, the safety assessment method for CANDU was studied by reviewing C documents and recommendation of IAEA. Through the present works, the vague policy in the CANDU safety regulation is cleaning up in a systematic form and a new frame to measure the objective risk of nuclear power plants was developed.

International Nuclear Information System (INIS)

During unit wise conditioning of unit 8, the vacuum started deteriorating inside the tube after a spark. The RGA reading was taken and it was found out that residual gas inside tube was sulphur hexafluoride. A leak was detected in second tube of unit number eight in between electrode 6 to 8. Leak was sealed with the sealant. Again leak check was done and no leak was found. The tank was closed and conditioning was started again. During the same unit number eight conditioning, leak developed again followed by a spark. So the damaged tube was replaced with a new accelerator tube. During the installation time the alignment of the machine was taken care. Again leak checking was done and the tube was baked properly. The tank was closed again and this particular unit was conditioned for about four days. The maximum voltage it has attained was 1.1 MV. (author)

CERN Document Server

We present experimental studies on the photoionization and photodissociation processes (photodestruction) of gaseous amino acids and nucleobases in interstellar and interplanetary radiation conditions analogs. The measurements have been undertaken at the Brazilian Synchrotron Light Laboratory (LNLS), employing vacuum ultraviolet (VUV) and soft X-ray photons. The experimental set up basically consists of a time-of-flight mass spectrometer kept under high vacuum conditions. Mass spectra were obtained using photoelectron photoion coincidence technique. We have shown that the amino acids are effectively more destroyed (up to 70-80%) by the stellar radiation than the nucleobases, mainly in the VUV. Since polycyclic aromatic hydrocarbons have the same survival capability and seem to be ubiquitous in the ISM, it is not unreasonable to predict that nucleobases could survive in the interstellar medium and/or in comets, even as a stable cation.

British Library Electronic Table of Contents (United Kingdom)

The light-emitting properties of cubic silicon carbide films grown by vacuum vapor phase epitaxy on Si(100) and Si(111) substrates under conditions of decreased growth temperatures (T gr ? 900?700?C) have been discussed. Structural investigations have revealed a nanocrystalline structure and, simultaneously, a homogeneity of the phase composition of the grown 3C-SiC films. Photoluminescence spectra of these structures under excitation of the electronic subsystem by a helium-cadmium laser (?excit = 325 nm) are characterized by a rather intense luminescence band with the maximum shifted toward the ultraviolet (?3 eV) region of the spectral range. It has been found that the integral curve of photoluminescence at low temperatures of measurements is split into a set of Lorentzian components. Th...

British Library Electronic Table of Contents (United Kingdom)

In this study three types of scanning electron microscopes were used for the size determination of spermatozoa of sterlet Acipenser ruthenus - high vacuum scanning electron microscope (SEM, JEOL 6300), environmental scanning electron microscope (ESEM, Quanta 200 FEG), field emission scanning electron microscope (FESEM, JEOL 7401F) with cryoattachment Alto 2500 (Gatan) and transmission electron microscope (TEM, JEOL 1010). The use of particular microscopes was tied with different specimen preparation techniques. The aim of this study was to evaluate to what degree the type of used electron microscope can influence the size of different parts of spermatozoa. For high vacuum SEM the specimen was prepared using two slightly different procedures. After chemical fixation with 2.5% glutaraldehyde...

International Nuclear Information System (INIS)

The present article will review recent advances in focused ion beam (FIB) technology. With increasing demands for scale of integration, microfabrication technology is becoming more important and various new microfabrication tools and processing techniques are desired. FIB is one of the promising tools for future microfabrication technology. This provides maskless patterning capability, which is of importance for process simplification, nanofabrication and in the development of in situ vacuum processing. In situ vacuum processing systems are being developed by combining FIB and a molecular beam epitaxy system. Radiation damage may limit applications of FIB. However, it was demonstrated that low energy FIB (<1 keV) with very high brightness was reached and promising results for low damage processing have been obtained. (orig.).

International Nuclear Information System (INIS)

The KSTAR cooling water system (CWS) consists of a primary cooling water system (PCWS), a secondary cooling water system (SCWS), and a de-mineralizing and de-ionized water system (DIWS). The PCWS cooling loops have been made for the poloidal field (PF) and toroidal field (TF) magnet power supplies (MPS), vacuum vessel (VV), electron cyclotron heating (ECH), ion cyclotron heating (ICRH), vacuum pumps, diagnostics, helium facility, etc. The CWS had been done individual commissioning of each system to confirm the design specifications by the end of 2006 and had gradually begun operation for the KSTAR ancillary devices by March 2008

International Nuclear Information System (INIS)

This paper discusses the mechanisms of gas breakdown at low values of pressure and inter-electrode gap, i.e. in the vicinity of the Paschen minimum. In this area of pressure and inter-electrode gap values, breakdown occurs either through gas or vacuum mechanisms, and also the so called anomalous Paschen effect appears. Electrical breakdown of electropositive, electronegative and noble gases has been investigated theoretically, experimentally and numerically. Based on the results obtained, regions in which particular breakdown mechanisms appear have been demarcated. Special attention has been devoted to the anomalous Paschen effect as well as to the avalanche vacuum breakdown mechanism.

International Nuclear Information System (INIS)

Within the framework of the Bianchi type-IX homogeneous space, we set up a system of coupled equations for the cosmic scale factors, scalar field, and radiative energy density. At the tree level, the equations are written in a self-consistent, Hartree-Fock form. For phi"4 theory, the system of nine first-order differential equations is solved numerically for a varying ratio of the energy of anisotropy to the vacuum energy. As the vacuum energy increases, there appears to be less reheating, since the energy of anisotropy is more efficiently converted into isotropic expansion. If the energy of anisotropy is large enough, the inflationary phase is prevented. In this case, a series of cosmological phase transitions will take place each time the square of the effective mass changes its sign.

Science.gov (United States)

A full-scale model of a rigid sectorial ring and a set of bellows which was covered with a temperature control layer and a coolant supply equipment was constructed to verify the adequacy of the heating and cooling system designed for JT-60. To cool and heat it effectively and to decrease the temperature differences among the various parts in the vacuum vessel, heater units and cooling pipes were located on the surface of the ring. The temperature control layer is to heat the vessel to 500/degree/sub //C within 70 hours and to maintain it at the temperature for 48 hours for simulating the state of bakeout. Subsequently the vessel is cooled down within about the same time as in heating. Prior to the series of tests, numerical analyses were performed to predict the cooling and heating efficiencies on the model and to examine the method of the temperature regulation.

British Library Electronic Table of Contents (United Kingdom)

By assuming that not only counter-ions but DNA molecules as well are thermally distributed according to a Boltzmann law, we propose a modified Poisson-Boltzmann equation, at the classical level, as a starting point to compute the effects of quantum fluctuations of the electric field on the interaction among DNA-cation complexes. The latter are modeled here as infinite one-dimensional wires (?-functions). Our goal is to single out such quantum-vacuum-driven interaction from the counterion-induced and water-related interactions. We obtain a universal, frustration-free Casimir-like (codimension 2) interaction that extensive numerical analysis show to be a good candidate to explain the formation and stability of DNA aggregates. Such Casimir energy is computed for a variety of configurations of...

CERN Document Server

Disorder on the string theory landscape may significantly affect dynamics of eternal inflation leading to the possibility for some vacua on the landscape to become dynamically preferable over others. We systematically study effects of a generic disorder on the landscape starting by identifying a sector with built-in disorder -- a set of de Sitter vacua corresponding to compactifications of the Type IIB string theory on Calabi-Yau manifolds with a number of warped Klebanov-Strassler throats attached randomly to the bulk part of the Calabi-Yau. Further, we derive continuum limit of the vacuum dynamics equations on the landscape. Using methods of dynamical renormalization group we determine the late time behavior of the probability distribution for an observer to measure a given value of the cosmological constant. We find the diffusion of the probability distribution to significantly slow down in sectors of the landscape where the number of nearest neighboring vacua ...

Energy Technology Data Exchange (ETDEWEB)

The use of vacuum multifoil (VMF) container for thermal insulation in long-life thermal batteries was investigated in a proof-of-concept demonstration. An InvenTek-designed VMF container 4.9 inches in diameter by 10 inches long was used with an internally heated aluminum block, to simulate a thermal-battery stack. The block was heated to 525 C or 600 C and allowed to cool while monitoring the temperature of the block and the external case at three locations with time. The data indicate that it should be possible to build an equivalent-sized thermal battery that should last up to six hours, which would meet the requirements for a long-life sonobuoy application.

International Nuclear Information System (INIS)

We investigate the quantum cosmology of spatially homogeneous models with compact spatial sections admitting a u(2) isometry algebra. The metric ansatz in these models is that of Bianchi type IX with two scale factors set to be equal. We apply the Hartle-Hawking no-boundary path integral prescription and find the semi-classical contributions to the wave function. Exact formulae are obtainable for certain contributions and otherwise the limits of large and small anisotropy (for the pure vacuum case) and large spatial volume or small anisotropy (for the case with a positive cosmological constant) are considered. For the pure vacuum case we find no semiclassical components which would correspond to Lorentzian universes. For the case with a cosmological constant the Hartle-Hawking boundary conditions formally constrain one of the parameters in the Lorentzian solutions to be purely imaginary. Possible interpretations of this imaginary parameter are ...

British Library Electronic Table of Contents (United Kingdom)

The design and operating principle of a small (50 mm in diameter and 100 mm in height) ???-73C vacuum spark gap are described. It is shown that it can be efficiently switched using a control circuit with a low (?900 V) supply voltage, which is based on an inductive energy storage and a diode opening switch that forms a high-voltage igniting pulse with a rise time of nanosecond duration. The ???-73C switching process is investigated at different rise times of igniting voltage pulses and different igniting current amplitudes. The results of tests of the spark gap operating in regimes of switching current pulses with an amplitude of 12 kA and a rise time of 800 ns are presented.

CERN Document Server

We have developed a liquid jet injector system that can be used for hydrated sample delivery at X-ray Free Electron Laser (XFEL) sources and 3rd generation synchrotron sources. The injector is based on the Gas Dynamic Virtual Nozzle (GDVN), which generates a liquid jet with diameter ranging from 300 nm to 20 {\\mu}m without the clogging problems associated with conventional Rayleigh jets. An improved nozzle design is presented here. A differential pumping system protects the vacuum chamber and an in-vacuum microscope allows observation of the liquid jet for diagnostics while it is being exposed to the X-ray beam. A fiber optically coupled pump laser illuminating the jet is incorporated for pump-probe experiments. First results with this injector system have been obtained at the LCLS.

Energy Technology Data Exchange (ETDEWEB)

A Bianchi type-IX cosmological model has been found as a solution of Einstien's vacuum field equations with a cosmological constant. The solution represents a rotating generalziation fo the de Sitter universe. This universe shows a transition to exponential expansion and the vorticity begins to decay exponentially at the grand-unified-theory time. The point of time for this transition is independent of the magnitude of the vorticity. During the Guth inflationary era the vorticity decays by a factor of the order 10 US.

International Nuclear Information System (INIS)

This paper extends the development of a new formulation of the theory of tachyons to encompass the dynamics of tachyons. Energy and momentum are discussed along with the proper mass of a tachyon. The transformation of force in extended relativity (ER) is derived. Acceleration in ER is also discussed, as well as the relationship between force and acceleration. Two simple examples relating to the motion of a charged tachyon are discussed, followed by a brief explanation of why tachyons cannot emit Cerenkov radiation in a vacuum. 13 refs., 3 figs.

Energy Technology Data Exchange (ETDEWEB)

The motion of an accelerated charge in a vacuum is analyzed, via the superposition principle and Fourier analysis, into uniform-motion components, which include bradyonic as well as tachyonic contributions. It is shown that the former contribute only to the induction fields whereas the latter are the source of the radiation emitted by the charge, via the Sommerfeld-Cerenkov mechanism. This result calls for a reexamination of some recently formulated theories of superluminal particles.

Energy Technology Data Exchange (ETDEWEB)

A Monte Carlo simulation of the vacuum Bianchi type-IX (mixmaster) cosmology yields a significant correlation between large universe volume and high anisotropy. An analog of the model's chaotic classical behavior is seen in the break up of the universe wave function at large volume into fingers in the corners of the minisuperspace anisotropy potential.

Energy Technology Data Exchange (ETDEWEB)

To suppress space charge blowup in an ion beam passing through a photoneutralizer, it is necessary to introduce some background gas. An analysis is presented of the neutralization of a high-energy, >200-keV negative deuterium ion beam, exposed to photodetachment while in the presence of deuterium. With a gas thickness of <0.01 Torr.cm, the neutral fraction in the output beam is found to be about the same as that gotten from the photoneutralizer operating in vacuum. Neutral atom beam injection for plasma heating is discussed.

Energy Technology Data Exchange (ETDEWEB)

An F-theory dual of a non-supersymmetric orientifold is considered. It is argued that the condensation of both open and closed string tachyons in the orientifold corresponds to the annihilation of branes and antibranes in the F-theory dual. One likely end-point of tachyon condensation is thus expected to be the vacuum of Type-IIB superstring. Some speculations are presented about the F-theory dual of the bosonic string and tachyon condensation thereof.

International Nuclear Information System (INIS)

A new external-PIXE system utilizing a differential pumping technique, which can completely protect the accelerator and vacuum pumps when the exit foil breaks down, has been developed. Applications to analyses of liquid and heavily-outgassing samples were successfully achieved. Also, experiments for evaluating the efficiency of the system were performed and results will be presented. (author)

Wastenet

... The products can be categorised as glazed flat-plate collectors, evacuated glass-tube collectors, and unglazed plastic or low temperature collectors. Glazed flat-plate collectors and vacuum tubes are widely used for solar water heating and space heating systems in all types of buildings. Unglazed plastic collectors are used exclusively for lower temperature applications, such as outdoor swimming pools or the agrarian business. Flat-plate solar collectors are likely to ...

Energy Technology Data Exchange (ETDEWEB)

In-situ air stripping employs horizontal wells to inject or sparge air into the ground water and vacuum extract VOC`S from vadose zone soils. The horizontal wells provide better access to the subsurface contamination, and the air sparging eliminates the need for surface ground water treatment systems and treats the subsurface in-situ. A full-scale demonstration was conducted at the Savannah River Plant in an area polluted with trichloroethylene and tetrachloroethylene. Results are described.

Energy Technology Data Exchange (ETDEWEB)

This document describes measurements of the directional spectral emittance of four ceramic mold materials. The work was performed with the samples at {approximately} 900{degree}C in a vacuum vessel pumped to {approximately}3 {times} 10{sup {minus}6}Torr. Results conform to expectations derived from prior work done with similar samples.

Energy Technology Data Exchange (ETDEWEB)

We have developed a novel insulator concept that involves the use of alternating layers of conductors and insulators with periods less than 1 mm. We have demonstrated that these structures perform 2 to 5 times better than conventional insulators in long pulse, short pulse, and alternating polarity applications. We present new testing results showing exceptional behavior at DC, with gradients in excess of 110kV/cm in vacuum.

International Nuclear Information System (INIS)

A higher-dimensional homogeneous spacetime is investigated satisfying the vacuum Einstein equations. It is assumed that the algebra of Killing vectors L admits a non-trivial Levi decomposition L=N+so(3), i.e. that the subalgebras N and so(3) do not commute. It is found that the model behaves in a non-chaotic way and cosmological dimensional reduction inevitably occurs. This model completes all the possible types within the class of higher-dimensional extensions of Bianchi type-IX cosmology. (orig.).

British Library Electronic Table of Contents (United Kingdom)

A web-based decision support tool, zone mapping application for precision farming (ZoneMAP, External Reference Not Shown ), has been developed to automatically determine the optimal number of management zones and delineate them using satellite imagery and field data provided by users. Application rates, such as of fertilizer, can be prescribed for each zone and downloaded in a variety of formats to ensure compatibility with GPS-enabled farming equipment. ZoneMAP is linked to Digital Northern Great Plains, a web-based application which hosts an archive of satellite imagery, as well as high resolution imagery from airborne sensors. Management zones created by ZoneMAP mapped natural variation of the soil organic matter and other nutrients relatively well and were consistent with zone maps cre...

Energy Technology Data Exchange (ETDEWEB)

As the Electric Power Industry is actively preparing for a restructured future where retail wheeling is practiced ideally and efficiently in a competitive market-based environment, concerns may arise legitimately on how system reliability and integrity can be ensured in an environment where markets have an enhanced role. As these concerns may be justified, at least for a transition period, this paper presents a proposal which outlines how the generally accepted requisite capacity, energy, and ancillary services standards may be satisfied through market reliance and minimal coordination by a Reliability Monitoring and Ancillary Services Managing Entity or Independent System Operator. A Strawman detailing one -- and by no means the only -- future scenario inspired by the recent NEPOOL restructuring discussions in New England is presented to demonstrate that market-based competition and flexibility are compatible with a reliable Power System.

Energy Technology Data Exchange (ETDEWEB)

This report covers the progress made on the title project for the project period. Four major areas of inquiry are being pursued. Advanced solid state NMR methods are being developed to assay the distribution of the various important functional groups that determine the reactivity of coals. Special attention is being paid to methods that are compatible with the very high magic angle sample spinning rates needed for operation at the high magnetic field strengths available today. Polarization inversion methods utilizing the difference in heat capacities of small groups of spins are particularly promising. Methods combining proton-proton spin diffusion with [sup 13]C CPMAS readout are being developed to determine the connectivity of functional groups in coals in a high sensitivity relay type of experiment. Additional work is aimed at delineating the role of methyl group rotation in the proton NMR relaxation behavior of coals.

British Library Electronic Table of Contents (United Kingdom)

Abstract Thermomechanical behavior of membranes based on blends of poly(vinyl alcohol) (PVA) with different weight percentage (wt %) of glycerol has been studied. Solid-state PVA/Glycerol polymer membranes were prepared by a solution casting method. The films were studied for thermal characteristics by differential scanning calorimetry (DSC) and thermogravimetric analysis and for the mechanical properties including hardness and modulus by nanoindentation method. The dispersion of glycerol within the polymer matrix was examined using scanning electron microscopy. Fourier transform infrared spectroscopy was used to confirm the formation of hydrogen bonding between the plasticizer and PVA in their blends and also to provide information on compatibility and physical interactions between the gl...

International Nuclear Information System (INIS)

Simple hydroxamic acids are shown to be useful reagents for the separation of Np and Pu from U within simplified, single cycle Purex flowsheets. They are compatible with the use of centrifugal contactors and laboratory scale flowsheet trials with aceto-hydroxamic acid have demonstrated high actinide recoveries and decontamination factors on products for active feeds of up to 40 wt.% Pu. They therefore show many ideal characteristics for Pu and Np recovery within flowsheet options for actinide recovery in advanced fuel cycles. Furthermore, in order to optimise the routing of Np with the Pu product in advanced flowsheets, additional studies of Np extraction in the primary co-decontamination contactor, prior to U/Pu partition, have been undertaken, combining experiment, modelling and flowsheet tests. (author)

CERN Document Server

We perform a systematic analysis of an extension of the Standard Model that includes a complex singlet scalar field and is scale invariant at the tree level. We call such a model the Minimal Scale Invariant extension of the Standard Model (MSISM). The tree-level scale invariance of the model is explicitly broken by quantum corrections, which can trigger electroweak symmetry breaking and potentially provide a mechanism for solving the gauge hierarchy problem. Even though the scale invariant Standard Model is not a realistic scenario, the addition of a complex singlet scalar field may result in a perturbative and phenomenologically viable theory. We present a complete classification of the flat directions which may occur in the classical scalar potential of the MSISM. After calculating the one-loop effective potential of the MSISM, we investigate a number of representative scenarios and determine their scalar boson mass spectra, as well as their perturbatively allowed parameter space ...

Energy Technology Data Exchange (ETDEWEB)

A full scale co-digestion system for sludge and Olive oil mill effluent (OME) and a regional sludge management plan has been set-up to solve urgent environmental problems, modifying an existing cold municipal digester, by means of simple and effective technology. Monitoring of the full scale system demonstrated good compatibility between OME and sludge, up to 20% mixture, and high removal of organics compounds. Coagulant compounds present in OME (mainly Fats), promoted aggregation and settling of anaerobic sludge and also its acetoclastic activity, minimizing the load returned to the wastewater treatment line and improving also the activated sludge system. The co-digestion of OME with sludge agreed the project purposes, and produced large quantity of biogas and electric energy.

International Nuclear Information System (INIS)

Over the last few years it has become increasingly clear that low energy, but high precision experiments provide a powerful and complementary window to physics beyond the Standard Model. In this note we illuminate this by using minicharged particles as an example. We argue that minicharged particles arise naturally in extensions of the Standard Model. Compatibility with charge quantization arguments suggests that minicharged particles typically arise together with a massless hidden sector U(1) gauge field. We present several low energy experiments employing strong lasers, electric and magnetic fields that can be used to search for (light) minicharged particles and their accompanying U(1) gauge boson.

Energy Technology Data Exchange (ETDEWEB)

This paper introduces the method of seismic stability analysis for the increase of fuel storage capacity of wet storage stacks by one or two more stack floor at Wolsung Nuclear Unit 2,3,4, which had been originally licensed assuming 16 tray stack-o-storage. As a basic procedure, tipping and sliding stability of the structure is checked at first thru seismic analysis and the resultant load from dynamic analysis is applied for static stress analysis, and the result of which is reviewed for compatability with applicable standard. As a result, sliding and overturning are not expected under design basis earthquakes for increased storage cases of 17 tray and 18 tray stacks. And it is anticipated the result of stress analysis will be acceptable.

CERN Document Server

We have searched for neutron-antineutron oscillations using the 5.56 fiducial kiloton-year exposure of the Soudan 2 iron tracking calorimeter. We require candidate n-nbar occurrences to have .GE. 4 prongs (tracks and showers) and to have kinematics compatible with nbar-N annihilation within a nucleus. We observe five candidate events, with an estimated background from atmospheric neutrino and cosmic ray induced events of 4.5 \\pm 1.2 events. Previous experiments with smaller exposures observed no candidates, with estimated background rates similar to this experiment. We set a lifetime lower limit for oscillation time in iron: T_A(Fe) > 7.2x10^{31} years. The corresponding lower limit for oscillation of free neutrons is \\tau_{n-nbar} > 1.3x10^8 seconds.

Energy Technology Data Exchange (ETDEWEB)

Process residues are generated at both the Rocky Flats Plant (RFP) and the Savannah River Plant (SRP) during aqueous chemical and pyrochemical operations. Frequently, process operations will result in either impure products or produce residues sufficiently contaminated with transuranics to be nondiscardable as waste. Purification and recovery flowsheets for process residues have been developed to generate solutions compatible with subsequent Purex operations and either solid or liquid waste suitable for disposal. The ''scrub alloy'' and the ''anode heel alloy'' are examples of materials generated at RFP which have been processed at SRP using the developed recovery flowsheets. Examples of process residues being generated at SRP for which flowsheets are under development include LECO crucibles and alpha-contaminated hydraulic oil.

British Library Electronic Table of Contents (United Kingdom)

Abstract Melamine cyanurate (MCA) was utilized as an environmental friendly additive to prepare the nonhalogen flame retardant MCA/Nylon 66 composites by melt blending technique. Because of the strong hydrogen bond interactions and fine interfacial compatibility between MCA and Nylon 66, the resultant even dispersion of MCA filler in polymer matrix leads to the better toughness and strength of MCA/Nylon 66 composites than those of neat Nylon 66. Both Nylon 66 and MCA/Nylon 66 composites exhibit similar -crystalline structure, but the presence of MCA influences the distribution of 1 and 2 crystalline phases in Nylon 66 by inducing its hydrogen-bonded sheet separation. Moreover, the blending of MCA and Nylon 66 increases the crystallization temperature and exothermicity but decreases the the...

Energy Technology Data Exchange (ETDEWEB)

The use of solvating polymers of polyether type is an interesting solution for the manufacturing of high capacity lithium batteries with lithium metal anodes and which can operate at T > 50 deg. C. These operating conditions are perfectly compatible with electric-powered vehicle and stationary battery applications. In order to improve the ionic conductivity of polymer electrolytes, new aprotic and amorphous polyether lattices have been synthesized having a good conductivity but also good thermal, mechanical and electrochemical stabilities. Two type of 3-D polyether lattices obtained by reticulation of linear pre-polymers have been selected as host polymers: unsaturated poly-condensate and unsaturated co-polyethers. (J.S.) 18 refs.

CERN Document Server

This thesis describes hadron reconstruction at the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC) at CERN, Geneva. The focus is on the particle flow reconstruction of these objects. This thesis revisits the subject of the CMS calorimeters' non-linear response to hadrons. Data from testbeam experiments conducted in 2006 & 2007 is compared with simulations and substantial differences are found. A particle flow calibration to correct the energy response of the testbeam data is evaluated. The reconstructed jet response is found to change by ~ 5% when a data-driven calibration is used in place of the calibration derived from simulation. Collision data taken at the early stage of CMS' commissioning is also presented. The hadron response in data is determined to be compatible with testbeam results presented in this thesis. This thesis also details the use of neural networks to improve the energy measurement of hadrons at CMS. The networks ...

Energy Technology Data Exchange (ETDEWEB)

The flow of current inside a conductor leads to its overheating. This conductor is also submitted to other climatic phenomena, such as wind, sun light and ambient temperature. The knowledge of this overheating is important to ensure a functioning temperature compatible with the materials used for the conductor manufacturing and with the dip of overhead power lines above the ground and buildings. On the other hand, according to the Laplace works, the flow of current inside parallel conductors induces electromagnetic forces inside them, proportional to the product of currents in both conductors. In the case of short-circuit between aerial power lines or between flexible cables, electrodynamical stresses (traction and flexion) are applied to insulators and holders and important swinging of the lines can be observed. These stresses can be extremely important and must be considered in the design of overhead lines. These two phenomena are analyzed in this chapter. (J.S.)

Energy Technology Data Exchange (ETDEWEB)

Theoretical investigations of fatty acids as a phase change material (PCM) for energy storage system have been conducted in this study. The selected fatty acids were capric acid, lauric acid, myristic acid, palmitic acid and stearic acid. For the two-dimensional simulation model based on the enthalpy approach, calculations have been made for the melt fraction with conduction only. Glass, stainless steel, tin, aluminium mixed, aluminium and copper were used as heat exchanger materials in the numerical calculations. Theoretical results show that capric acid was found good compatibility with latent heat storage system. The large value of thermal conductivity of heat exchanger materials did not make significant contribution on the melt fraction. (author)

CERN Document Server

We present a detailed analysis of the self-organization phenomenon in which the stylized facts originate from finite size effects with respect to the number of agents considered and disappear in the limit of an infinite population. By introducing the possibility that agents can enter or leave the market depending on the behavior of the price, it is possible to show that the system self-organizes in a regime with a finite number of agents which corresponds to the stylized facts. The mechanism to enter or leave the market is based on the idea that a too stable market is unappealing for traders while the presence of price movements attracts agents to enter and speculate on the market. We show that this mechanism is also compatible with the idea that agents are scared by a noisy and risky market at shorter time scales. We also show that the mechanism for self-organization is robust with respect to variations of the exit/entry rules and that the attempt to trigger the ...

Energy Technology Data Exchange (ETDEWEB)

A noninvasive method is described for estimating local cerebral blood flow (LCBF) and local partition coefficients by means of computed tomographic scanning during inhalation of 30% stable xenon gas in oxygen. Time-dependent xenon concentrations in arterial blood and brain tissue during the wash-in and washout phases are used to calculate partition coefficients and LCBF values by means of a least-squares curve-fitting analysis. Control values for partition coefficient and LCBF obtained from control subjects with minor head trauma in the chronic stage were compatible with those in several past reports, and reproducibility was satisfactory. The theoretic grounds underlying this new method of curve-fitting analysis are discussed.

British Library Electronic Table of Contents (United Kingdom)

Considering the status of knowledge on corrosion and corrosion protection and especially the need for long term compatibility data of structural materials in HLM a set of experiments to generate reliable long term data was defined and performed. The long term corrosion behaviour of the two structural materials foreseen in ADS, 316L and T91, was investigated in the design relevant temperature field, i.e. from 300 to 550degreeC. The operational window of the two steels in this temperature range was identified and all oxidation data were used to develop and validate the models of oxide scale growth in PbBi. A mechanistic model capable to predict the oxidation rate applying some experimentally fitted parameters has been developed. This model assumes parabolic oxidation and might be used for de...

British Library Electronic Table of Contents (United Kingdom)

In this work, a highly-sensitive polymeric membrane ion selective electrode for determination of tetracycline was constructed by using molecularly imprinted polymer (MIP) particles as quasi-ionophore. The water-compatible MIP particles targeting tetracycline were synthesized with tetracycline as a template molecule, methacrylic acid as a functional monomer, ethylene glycol dimethacrylate as a cross-linker, 2,2?-azobisisobutyronitrile as an initiator and lanthanum ion as a mediator. Benefited from the distinctive performance of the quasi-ionophore and the optimized composition of the membrane and the inner filling solution, the lower detection limit of the electrode was decreased to about 1 ? 10?8 mol/l. It exhibited a good electrode slope 59.8 mV/decade near the theoretical Nernstian one, ...

Science.gov (United States)

In this work, the half-life of the {sup 155}Sm beta{sup -} decay was determined using enriched {sup 154}Sm samples submitted to irradiation in the IEA-R1 reactor of IPEN; the activity of the samples were followed for 4-5 consecutive half lives using a 198 cm{sup 3} HPGe detector. The data was corrected using a non paralizable dead time correction and fitted to an exponential decay function using a non linear fitting procedure developed on the MatLab platform. The resulting value--T{sub 1/2} = 22.180(26) min--was compatible to the one found in the literature, with a lower uncertainty.

Energy Technology Data Exchange (ETDEWEB)

The purpose of this note is to provide guidance to those who have duties under the Health and Safety at Work Act and other relevant legislation. It gives guidance on the practical application of legislation, concerning radiotherapy equipment. Two particular issues arise out of the requirements of Regulation 33 of the Ionising Radiations Regulations 1985 (IRR85) in relation to equipment which is used for medical exposures. These are the requirement to select, install and maintain this type of equipment in such a way that it is capable of restricting, so far as reasonably practicable, the medical exposure of any person where this is compatible with the intended clinical purpose, including the need to ensure that equipment used for radiotherapy is properly calibrated, and the requirement to notify the Health and Safety Executive (HSE) when an incident occurs involving a malfunction or defect in any 'radiation equipment' which gives rise to a medical ...

International Nuclear Information System (INIS)

An estimation method of plasma density based on surface plasmons theory for surface-wave plasmas is proposed. The number of standing-wave is obtained directly from the discharge image, and the propagation constant is calculated with the trim size of the apparatus in this methods, then plasma density can be determined with the value of 9.1 x 1017 m-3. Plasma density is measured using a Langmuir probe, the value is 8.1 x 1017 m-3 which is very close to the predicted value of surface plasmons theory. Numerical simulation is used to check the number of standing-wave by the finite-difference time-domain (FDTD) method also. All results are compatible both of theoretical analysis and experimental measurement. (authors)

Energy Technology Data Exchange (ETDEWEB)

Environmental compatibility is nowadays a very important part in the case of planing, construction, operation and maintainance of cable systems. A lot of laws and orders have to be observed. Some new aspects concerning the removal of oil filled cables and the consideration of electromagnetic fields even for cabels will be presented. (orig.) [Deutsch] Der Umweltschutz ist heute unverzichtbarer Bestandteil der Planung, Bau, Betrieb und Instandhaltung von Kabelanlagen. Zahlreiche Gesetze und Verordnungen sind hierbei zu beachten. Der Verfasser stellt einige Neuerungen im Zusammenhang mit dem Ausbau und Oelkabeln vor und erlaeutert die auch bei Kabeln zu beruecksichtigenden elektromagnetischen Felder. (orig.)

British Library Electronic Table of Contents (United Kingdom)

Statement of problem Titanium is the most biocompatible metal used for dental casting; however, there is concern about its marginal accuracy after porcelain application since this aspect has direct influence on marginal fit. Purpose The purpose of this study was to determine the effect that metal selection and the porcelain firing procedure have on the marginal accuracy of metal ceramic prostheses. Material and methods Cast CP Ti, milled CP Ti, cast Ti-6Al-7Nb, and cast Ni-Cr copings (n=5) were fired with compatible porcelains (Triceram for titanium-based metals and VITA VMK 95 for Ni-Cr alloy). The Ni-Cr alloy fired with its porcelain served as the control. Photographs of metal copings placed on a master die were made. Marginal discrepancy was determined on the photographs using an image ...

International Nuclear Information System (INIS)

The energy levels, wavelengths, oscillator strengths, Auger rates and level-to-level dielectronic recombination rate coefficients describing dielectronic recombination into excited levels of Ne-like titanium from F-like low-lying states are calculated. Our calculations are based on Dr. R.D. Cowan's semi-relativistic mass-velocity and Darwin corrections are included in the Hamiltonian, and the distorted-wave model is used for the calculation of free electron wavefunctions. In order to set the recombination rate coefficients on a level by level basis, in a manner compatible with detailed level population kinetics modelling of highly-stripped ions in plasma, the dielectronic recombination rate coefficients as a function of free electron temperatures are given in an analytical form, which is not only very convenient in practice, but also hopefully accurate compared with the exactly calculated numerical results. (orig.).

Energy Technology Data Exchange (ETDEWEB)

Contact scanner system in Wolsung NPP(model ESE-1565) is early `70 equipment so most of components are obsolete. To make 100% compatible PCBs for this system is main object of the study. Most of components used in the system are now not available in the electric market, furthermore original system maker no longer supplies spare parts. System supplier(AECL) quoted lots of money than general PCBs prices in case of spare PCBs are re-marked by canada maker. Contents and scope of the study are specifications research and system analysis, improvements of repairability and reliability, circuit design and simulations using computer aided tools(CAE), make arbitrary mechanical contacts signal generator for test system. Now the long-run test of home made PCBs are conducting at Wolsung NPP. (author). 20 refs., 42 figs.

Energy Technology Data Exchange (ETDEWEB)

Accelerated aging tests on gold bridgewired detonator assemblies to determine compatibility of the Au and Pd-In-Sn solder with the organic explosive, PENT, have revealed an unusual corrosion process. These tests, conducted at 74/sup 0/C and 54/sup 0/C indicated a preferential attack of the gold. A matrix of corrosion test units was established to study this corrosion problem with accelerating temperatures up to 100/sup 0/C. Scanning electron microscopy (SEM), energy dispersive x-ray (EDX), and x-ray diffraction techniques were used to determine the extent of the corrosion and identify the corrosion products. Results indicate the preferential attack of the gold was due to HCN formed by decomposition of the explosive powder (PETN) at high temperatures. Other associated reactions were also observed including subsequent attack of the solder by the gold corrosion product and degradation of the plastic header.

Energy Technology Data Exchange (ETDEWEB)

The relationship between X chromosome-linked adrenoleukodystrophy and the red/green color pigment gene cluster on Xq28 was investigated in a large kindred. The DNA in a hemizygous male showed altered restriction fragment sizes compatible with at least a deletion extending from the 5[prime] end of the color pigment genes. Segregation analysis using a DNA probe within the color pigment gene cluster showed significant linkage with adrenoleukodystrophy (logarithm of odds score of 3.19 at [theta] = 0.0). These data demonstrate linkage, rather than association, between a unique molecular rearrangement in the color pigment gene cluster and adrenoleukodystrophy. The DNA changes in this region are thus likely to be helpful for determining the location and identity of the responsible gene. 33 refs., 4 figs.

British Library Electronic Table of Contents (United Kingdom)

In the present study, we report the occurrence of Lyme's borreliosis in patients from the Brazilian Amazon Region. Borreliosis was investigated by immunohistochemistry and focus floating microscopy for Borrelia burgdorferi in skin biopsy samples from 22 patients with both clinical and histopathology evidences compatible with Erythema Migrans. Spirochetes were detected by specific immunohistochemistry and focus floating microscopy for B. burgdorferi in samples from five patients. Clinical cure of the cutaneous lesions was observed in all the patients after treatment with doxycycline regimen as proposed by the Center Disease Control guidelines. A limitation of our study was the fact that we were not able to isolate and culture these organisms. These are the first known Brazilian cases of bor...

Energy Technology Data Exchange (ETDEWEB)

The overall aim is to develope programme modules for a Danish integrated computer system for projecting buildings and to ensure that Danish programmes are compatible with international systems. The programmes to be integrated here were AutoCAD and SCRIBE-Models and the simulation programme tsbi3 for the calculation of indoor climate conditions, power demand and energy consumption in buildings. For the calculation of humidity and temperature conditions in constructions a certain amount of integration is carried out with the MATCH programme (Moisture And Temperature calculations for Constructions of Hygroscopic materials). The activities embodied in the pilot projects are described in this working report in addition to individual computer programmes and prototypes, and examples and diagrams are presented. The programmes described deal with handling design elements in relation to AutoCAD designs, and the formatting of a building`s data from AutoCAD to tsbi3 format. ...

Energy Technology Data Exchange (ETDEWEB)

AZ31 Mg alloy samples were extruded by an equal channel angular extrusion (ECAE) process and subsequently annealed to obtain fine-grained material with a low dislocation density. Tensile tests at room temperature exhibited an apparent steady-state deformation region and a large tensile elongation of 47%. The deformed microstructure at an elongation of 2% indicated a substantial cross-slip to nonbasal planes possibly induced by grain-boundary compatibility effects. The nonbasal segments of dislocations were found to consist of 40% of the total dislocation density at a yield anisotropy factor of only 1.1 instead of an expected value of 100 from single-crystal experiments. (orig.)

International Nuclear Information System (INIS)

Until the last decade it had been almost universally held that a consequence of the special theory of relativity was that particle velocities greater than the velocity of light were not possible. It was however pointed out that provided super-luminary particles were created and remained super-luminary, then a redefinition of their mass was possible which was compatible with relativity. There was thus no a priori reason for dismissing the existence of tachyons. Work has been done at Adelaide to detect effects which appear to precede substantially the highly relativistic particles in cosmic ray showers and could therefore be associated with tachyons. Results seem to suggest that some non-random effects may be observable in the time period up to 100#mu#s before the observation of air showers. (author).

Energy Technology Data Exchange (ETDEWEB)

This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The main objective of this project was to engineer and procure an electron beamline compatible with the operation of a 1-kW free-electron laser (FEL). Another major task is the physics design of the electron beam line from the end of the wiggler to the electron beam dump. This task is especially difficult because electron beam is expected to have 20 kW of average power and to simultaneously have a 25% energy spread. The project goals were accomplished. The high-power electron design was completed. All of the hardware necessary for high-power operation was designed and procured.

International Nuclear Information System (INIS)

Given the local observables in the vacuum sector fulfilling a few basic principles of local quantum theory, we show that the superselection structure, intrinsically determined a priori, can always be described by a unique compact global gauge group acting on a field algebra generated by field operators which commute or anticommute at spacelike separations. The field algebra and the gauge group are constructed simultaneously from the local observables. There will be sectors obeying parastatistics, and intrinsic notion derived from the observables, if and only if the gauge group is non-Abelian. Topological charges would manifest themselves in field operators associated with spacelike cones but not localizable in bounded regions of Minkowski space. No assumption on the particle spectrum or even on the covariance of the theory is made. However the notion of superselection sector is tailored to theories without massless particles. When translation or Poincare covariance ...

International Nuclear Information System (INIS)

Alcaptonuria is a rare autosomal recessive metabolic disease, due to the lack of homogentisic acid oxidase. The following accumulation of homogentisic acid brings about a black discoloration of both the urine alcaptonuria) and connective tissue (ochronosis). The ochronotic alterations into joint cartilages cause degenerative arthropathy and osteopenia. The radiological features of three unrelated cases of alcaptonuria are reported. Radiographic abnormalities of ochconotic arthropathy are found in both the spine and the extraspinal joints. In the spine, the progressive calcification and ''vacuum'' phenomenon of disc spaces are the most characteristic findings. Disc space narrowing is associated with calcification and marginal sclerosis of vertebral bodies and is accentuated by osteopenia. Osteophytes are usually absent or of small size; neverthless progressive formation of marginal intervertebral bridges and obliteration of disc spaces at multiple levels ...

International Nuclear Information System (INIS)

The far infrared free electron laser (FEL) has been being developed since 1990 using the L-band electron linac at the Institute of Scientific and Industrial Research, Osaka University. The first lasing was obtained in 1994 at wavelengths from 32 to 40 #mu#m. The FEL is now being modified suitable for user experiments. The wiggler with a fixed magnet gap used in the original FEL has been remodeled to make the magnet gap variable. In order to optimize the variable range of the gap, the gain and the diffraction loss were calculated. The peak gain is calculated to be 270% and the diffraction loss to be 22% at 150 #mu#m. The wavelength is expected to be variable from 25 up to at least 150 #mu#m. The two bending magnets in the optical resonator have been remodeled and the vacuum chambers with larger vertical sizes for them have been newly made so that the diffraction loss in these parts becomes smaller than that in the vacuum chamber of the wiggler. ...

International Nuclear Information System (INIS)

Measurements of the Kapitza conductance to liquid helium II across the (100) surface of single crystals of copper are presented. The temperature range of these measurements was 1.6-- 2.1 K. The sample surfaces were subjected to several different treatments. Some surfaces were cleaned by low-energy argon ion bombardment, annealed in an ultrahigh-vacuum system, and preserved under vacuum until purified liquid helium was admitted. Other surfaces were intentionally damaged by machining and/or exposure to the atmosphere. The conductance after these latter treatments was found to be about a factor of three higher than that of the more ideally cleaned and annealed surfaces, and a significant difference in the temperature dependence of the conductance was also observed. Conductances were reproducible for similarly treated surfaces and correlated with surface damage determined by x-ray diffraction. The relationship of these results to the numerous ...

Energy Technology Data Exchange (ETDEWEB)

Pd was deposited onto Si (111) 7x7 surface at approximately 700 K inside an ultrahigh vacuum transmission electron microscope. Plan-viewed transmission electron microscopy (TEM) observation indicated that the islands have two kinds of shapes, round and rectangular (one-dimensional) ones. In a diffraction pattern for the rectangular islands, extra spots along the <110> direction of the Si surface, spacing of which is 1/8 times as long as that of Si (220) spots, were seen. A high resolution TEM image showed the corresponding superstructure in the rectangular islands. In situ observation of the growing process of the rectangular islands showed repeat of introduction and relief of strains during the growth, suggesting that such superstructure would be constructed by stacking compositionally different phases or introducing defects so that the periodically maximized strain is relieved.

International Nuclear Information System (INIS)

The quantum behavior of the vacuum Bianchi type-IX universe with the cosmological constant is investigated in terms of the Ashtekar variables. An exact solution to the quantum Hamiltonian constraint in the holomorphic representation is given. This solution reduces to the Hartle-Hawking wave function in the spatially isotropic sector and extends in the triad representation to the classically forbidden region where the determinant of the spatial metric becomes negative. The analysis of the quantum Robertson-Walker universe indicates that if the superspace is extended to such a classically forbidden region, the holomorphic representation picks up some restricted class of solutions in general. This observation leads to a new ansatz on the boundary condition of the Universe. In particular, the behavior of the Lorentzian and Euclidean WKB orbits corresponding to the solution suggests a new picture on the semiclassical behavior of the quantum Universe: that the Universe ...

International Nuclear Information System (INIS)

The principle and history of free-electron laser (FEL), first evidenced in 1977, the relationship between FEL wavelength and output power, the high-power FEL driven by the superconducting linac, the X-ray FEL by the linac, and the medical use are described. FEL is the vacuum oscillator tube and essentially composed from the high-energy linac, undulator and light-resonator. It utilizes free electrons in the vacuum to generate the beam with wavelength ranging from microwave to gamma ray. The first high-power FEL developed in Japanese Atomic Energy Research Institute (JAERI) is based on the development of superconducting linac for oscillating the highest power beam. In the medical field, applications to excise brain tumors (in US) and to reconstruct experimentally blood vessels in the pig heart (in Gunma University) by lasing and laser coagulator are in progress with examinations to remove intra-vascular cholesterol mass by irradiation of 5.7#mu#m ...

International Nuclear Information System (INIS)

Ceramic matrix composites in the TiC-Ti, Y-TZP system can be synthesized by the reaction between carbon and the TiO_2-Y_2O_3-ZrO_2 solid solution nanopowder. This method results in the more homogeneous powders than those prepared by the physical mixing of TiC and zirconia s.s. powders. Twelve TiO_2-Y_2O_3-ZrO_2 solid solution nanopowders differing in the proportions of the constituent oxides were prepared by the coprecipitation- calcination route. They were reacted with the pyrolytic carbon evenly distributed within the system. Carbon was introduced by the thermal decomposition of the phenol-formaldehyde resin dissolved in ethyl alcohol and mixed with the zirconia s.s. nanopowder. Reaction was performed in vacuum. Compacts of the composite powders sintered in vacuum give dense materials of evenly distributed TiC inclusions of sizes not surpassing 400 nm. Hardness of such materials was dependent on their chemical and phase composition but was ...

International Nuclear Information System (INIS)

We investigate the quantum cosmology of spatially homogeneous models with compact spatial sections admitting a u(2) isometry algebra. The metric ansatz in these models is that of Bianchi type IX with two scale factors set to be equal. We apply the Hartle-Hawking no-boundary path integral prescription and find the semi-classical contributions to the wave function. Exact formulae are obtainable for certain contributions and otherwise the limits of large and small anisotropy (for the pure vacuum case) and large spatial volume or small anisotropy (for the case with a positive cosmological constant) are considered. For the pure vacuum case we find no rapidly oscillating semiclassical components in the wave function, and hence do not recover lorentzian space-time as a prediction of the no-boundary proposal. For the case with a cosmological constant the wave function does contain rapidly oscillating components and thus predicts approximately ...

International Nuclear Information System (INIS)

The structure of a demountable vacuum joint designed for operation from -120 to +120 deg C is developed and tested. Requirements of especially low gas release from the materials used have been fulfilled; the same concerns low sealing efforts, repeated action and keeping tightness under loads, indium being used as a sealant. Experimental studies of demountable vacuum joints, dia 100,125,140,160,180 and 200 mm, with an indium sealant permit to make the following conclusions: 1. The joints are sealed at sealing specific efforts of 0.4 kg/mm (without considering atmospheric pressure). 2. The joints retain tightness at opening and closing a cover five times and under +-120 deg C. 3. To ensure repeated operation of the joint with continued stable sealing effort, one should make sure the sealed surfaces coincide at repeated sealing. 4. When operating demountable vaccum joints with indium sealant, one must take into account the time factor, since time ...

Energy Technology Data Exchange (ETDEWEB)

A nuclear battery based on the direct energy conversion of the fission products is presented. Such energy conversion is possible by using a nuclear reactor with ultra-thin fuel elements of 0.2 {mu}m of {sup 242m}Am. The amount of nuclear fuel is 376 g and the dimensions of the battery are 2.4x2.4x2.4 m{sup 3} (including the vacuum spacing), with a BeO moderator and Be electrodes. The total power of the reactor is 10.6 MW and the electrical power is 0.652 MW.

Energy Technology Data Exchange (ETDEWEB)

This paper reports on the results of experiments into efficient higher-order anti-Stokes Raman conversion of tunable short-pulse XeCl laser radiation. The maximum output energy of the pumping laser, in which the radiation of a frequency-doubled dye laser is amplified by two XeCl laser amplifiers, is 55 mJ with a pulse duration of 1 ns FWHM. Using hydrogen gas as a Raman medium, a series of anti-Stokes lines up to the 12th order (121.5 nm) is generated in the vacuum ultraviolet (VUV) region. 16 references.

Science.gov (United States)

A nitrogen liquefier and computer controlled valving system have been added to the Bevatron cryoliner vacuum system to cut operating costs by reducing liquid nitrogen consumption. The computer and interface electronic systems, which control the temperatures of twenty-eight liquid nitrogen circuits, have been chosen and designed to operate in the Bevatron's pulsating magnetic field. The nitrogen exhaust is routed back to a liquefier, of about five kilowatt capacity, liquefied, and rerouted through the cooling circuits. A description of the system and operating results are presented.

British Library Electronic Table of Contents (United Kingdom)

Methods of X-ray diffraction and transmission electron microscopy were used to study the microstructure of dispersion-strengthened Cu-Al2O3 nanocomposites obtained by the method of simultaneous deposition of Cu and Al2O3 from the vapor phase. The effect of the size of particles of the oxide (Al2O3) and of their content on the electrical resistance of the composite has been considered. The results obtained make it possible to suppose that the main structural factor that determines the electrical resistance of the composite are nanodispersed particles of Al2O3 with a size of less than 20 nm.

CERN Document Server

We study quantum Darwinism -- the redundant recording of information about a decohering system by its environment -- in zero-temperature quantum Brownian motion. An initially nonlocal quantum state leaves a record whose redundancy increases rapidly with its spatial extent. Significant delocalization (e.g., a Schroedinger's Cat state) causes high redundancy: many observers can measure the system's position without perturbing it. This explains the objective (i.e. classical) existence of einselected, decoherence-resistant pointer states of macroscopic objects.

International Nuclear Information System (INIS)

We construct a phenomenological model which describes the dynamical chiral symmetry breaking (DCSB) of a QCD vacuum and reproduces meson spectra. Quark condensates, the pion decay constant, and meson spectra are well reproduced by the phenomenological interaction which consists of a linear confining potential, a Coulombic potential, and the close-quote t Hooft determinant interaction. In this model, the close-quote t Hooft determinant interaction plays an important role to not only the mass difference between the #eta# and #eta#"' mesons, but other meson masses through DCSB. copyright 1997 The American Physical Society.

Energy Technology Data Exchange (ETDEWEB)

Procedures are described to mechanize partially harvesting, cleaning, and pretreatment of guayule achenes. Achenes are harvested with a vacuum insect net and cleaned by a series of screening, threshing, and forced air separations, then treated to overcome seed coat impermeability in a semiautomatic system that presoaks, treats with 0.5% sodium hypochlorite, and rinses. Achenes may be sown immediately or dried for storage. Procedures outlined involve commercially available equipment with a minimum of custom construction and are adaptable to small or large operations. (Refs. 11).

Science.gov (United States)

Self-magnetically insulated, high-voltage transmission lines are used in inertial confinement fusion particle accelerators in order to transmit power from the vacuum insulator to the diode. This paper describes a time-dependent 2-D code (MITL) for calculating (for planar or triplate geometries) the motion of test electrons through the tapered input or output convolutes of such lines. MITL results show that the electron canonical momentum in the direction of the flow changes as the electron passes through the convoluted geometry; it is suggested that these electrons lead to losses observed in long self-magnetically insulated lines.

International Nuclear Information System (INIS)

Laser gain of the NIJI-IV compact storage-ring-based Free Electron Laser (FEL) system at AIST reached #approx#9% at 200 nm for an average beam current of 16.3 mA. In addition to such a drastic gain enhancement, improvement of the laser-cavity performance has led to successful FEL lasing in the vacuum ultraviolet below 200 nm even in a compact system. Temporal and spectral characteristics of the NIJI-IV FEL were examined around 200 nm. FEL performance will be briefly discussed from the application point of view.

CERN Document Server

The influence of motion of ions and electron temperature on nonlinear one-dimensional plasma waves with velocity close to the speed of light in vacuum investigated. It is shown that although the wavebreaking field weakly depends on mass of ions, the nonlinear relativistic wavelength essentially changes. The nonlinearity leads to the increase of the strong plasma wavelength, while the motion of ions leads to the decrease of the wavelength. Both hydrodynamic approach and kinetic one, based on Vlasov-Poisson equations, are used to investigate the relativistic strong plasma waves in a warm plasma. The existence of relativistic solitons in a thermal plasma is predicted.

Energy Technology Data Exchange (ETDEWEB)

In situ air stripping (ISAS) technology was developed to remediate soils and ground water contaminated with volatile organic compounds (VOCs) both above and below the water table. ISAS employs horizontal wells to inject (sparge) air into the ground water and vacuum extract VOCs from vadose zone soils. The innovation is creation of a system that combines two somewhat innovative technologies, air sparging and horizontal wells, with a baseline technology, soil vapor extraction, to produce a more efficient in situ remediation system.

Energy Technology Data Exchange (ETDEWEB)

In Situ Bioremediation (ISB), which is the term used in this report for Gaseous Nutrient Injection for In Situ Bioremediation, remediates soils and ground water contaminated with volatile organic compounds (VOCs) both above and below the water table. ISB involves injection of air and nutrients (sparging and biostimulation) into the ground water and vacuum extraction to remove .VOCs from the vadose zone concomitant with biodegradation of VOCs. The innovation is in the combination of 3 emerging technologies, air stripping, horizontal wells, and bioremediation via gaseous nutrient injection with a baseline technology, soil vapor extraction, to produce a more efficient in situ remediation system.

CERN Document Server

We carry out a Lie group analysis of the Sachs equations for a time-dependent axisymmetric non-rotating space-time in which the Ricci tensor vanishes. These equations, which are the first two members of the set of Newman-Penrose equations, define the characteristic initial-value problem for the space-time. We find a particular form for the initial data such that these equations admit a Lie symmetry, and so defines a geometrically special class of such spacetimes. These should additionally be of particular physical interest because of this special geometric feature.

Energy Technology Data Exchange (ETDEWEB)

The authors investigated phase equilibria in the system carbon dioxide-hexametapol. Vacuum-distilled solvent of ''pure'' grade was used. The solubility of CO/sub 2/ in hexametapol under pressures at various temperatures and the temperature dependence of the Henry's law coefficient is show. It is concluded that the solubility of carbon dioxide in hexametapol in the temperature and pressure ranges corresponding to the operating conditions of industrial equipment for removing CO/sub 2/ from gases conforms to the Krichevskii-II'inskaya equation. The experimental data can be used for equipment design.

International Nuclear Information System (INIS)

The fabrication of the ZT-40 torus, a large complex all-ceramic toroidal plasma containment vessel, is described. Several glass sealants covering the temperature range of 500 to 1300"0C, were developed and used to ''braze'' segments of the torus together, sapphire windows to the torus and the required pump-out and diagnostic parts to the ceramic vacuum vessel. Designs of window seals were developed that allowed sealing of the sapphire windows in a vertical position with minimum sealing glass flow.

International Nuclear Information System (INIS)

Two species of wood, viz. Haldu (Adina Cordifolia) and Jamun (Syzygium Cumini) were vacuum-impregnated with two styrene-based monomer systems and polymerized in situ with gamma radiation from a cobalt-60 source. The electrical conductivity of these specimens was determined at various polymer loadings under dry conditions, after wetting and after wet recovery as per ASTM standards. The water absorption characteristics are also presented. The results are discussed with special reference to the role of water. Potential applications are also discussed. 7 figures.

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In order to investigate the influence of grain boundary cavities on the life time of Alloy 800 H various fatigue tests have been performed at 800/sup 0/C. Cavity formation has been observed only in asymmetrical tests. Compared to the corresponding symmetrical tests, the cyclic life time is shorter. As the cavitation damage increases, the ratio of life times in vacuum and in air steadily decreases from an initial value of 5. In extreme cases it can reach a value close to 1. In this case, cavitation damage dominates over the usual damage mechanism, which is cracks from the surface.

International Nuclear Information System (INIS)

The current status of research and development in the realm of physics and technology of collective ion acceleration in systems with a virtual cathode (VC) is reviewed. Three major acceleration methods and devices developed on their basis are considered: reflex triodes and their modifications, gas-filled vircators, and vacuum vircators with a Luce diode. Experimental data are outlined and the principal physical models interpreting these data are described. New ion acceleration techniques whose realization involves the production and disappearance of the VC are also discussed. All methods of collective ion acceleration are compared and the possible ways for the further development of this promising scientific field are highlighted. (reviews of topical problems)

International Nuclear Information System (INIS)

The inelastic scattering of the beam and the residual gas molecules in RHIC could represent one of the limitations on the beam life time and emittance growth. This report covers the dominant central nuclear collisions influence on the beam lifetime and transverse emittance growth. The cross sections for the beam-gas electron radiative captures are an order of magnitude smaller. The capture cross sections include the radiative and non-radiative capture, and the capture from the electron-positron pair creation from the 'vacuum capture'.

Energy Technology Data Exchange (ETDEWEB)

The formation of a quasiequilibrium beam distribution matched to an alternating-gradient quadrupole focusing lattice by means of the adiabatic turn-on of the oscillating focusing field is studied numerically using particle-in-cell simulations. Quiescent beam propagation over several hundred lattice periods is demonstrated for a broad range of beam intensities and vacuum phase advances describing the strength of the oscillating focusing field. Properties of the matched-beam distribution are investigated. In particular, self-similar evolution of the beam density profile is observed over a wide range of system parameters. The numerical simulations are performed using the WARP particle-in-cell code.

International Nuclear Information System (INIS)

The economic value of environmental goods is commonly determined using the concepts of willingness to pay (WTP) or willingness to accept (WTA). However, the WTP/WTA observed in different countries (or between individuals) will differ according to socio-economic characteristics, in particular income. This notion of differentiated values for otherwise identical goods (say, a given reduction in mortality risk) has been criticized as unethical, most recently in the context of the 'social cost' chapter of the IPCC Second Assessment Report. These critics argue that, being a function of income, WTP/WTA estimates reflect the unfairness in the current income distribution, and for equity reasons uniform per-unit values should therefore be applied across individuals and countries. This paper analyses the role of equity in the aggregation of climate change damage estimates, using basic tools of welfare economics. It shows one way of how WTP/WTA estimates can be corrected in aggregation if the ...

International Nuclear Information System (INIS)

The complex phase relationships near the BaO-poor region of the quaternary Ba-Sm-Y-Cu-O oxide system prepared in pure air (pO2=22 kPa, 950 oC) and in 0.1% O2 (pO2=100 Pa, 810 oC) have been determined. This investigation also included the subsolidus compatibilities in ten subsystems (Ba-Sm-Y-O, Ba-Sm-Cu-O, Ba-Y-Cu-O, Sm-Y-Cu-O, Ba-Sm-O, Ba-Y-O, Ba-Cu-O, Sm-Y-O, Sm-Cu-O, and Y-Cu-O), and the homogeneity range of five solid solutions (Ba(SmxY2-x)CuO5, (Sm,Y)2O3, (Sm,Y)2CuO4, (Y,Sm)2Cu2O5, and Ba(Sm,Y)2O4). The single phase range of the superconductor solid solution, (Ba2-xSmx)(Sm1-yYy)Cu3O6+z, and the phase compatibilities in its vicinity, which are particularly important for processing, are described in detail. The phase equilibrium data of the Ba-Sm-Y-Cu-O system will enable the improvement of the intrinsic superconducting properties of second-generation wires, and facilitate the flux-pinning process. -- Graphical Abstract: Phase diagram ...

International Nuclear Information System (INIS)

Fracture toughness data of pre-cracked Charpy single-edge bend, SE(B), specimens are compared with those of standard compact, C(T), specimens in the upper shelf and ductile-to-brittle transition regimes. Charpy sized SE(B) specimens provide ductile fracture toughness data, which are compatible with those of standard C(T) specimens. Statistical methods such as the exponential curve fitting method (ECF), the engineering lower bound toughness method (ELB), and the Master Curve method (MC) are used to provide meaningful lower bound cleavage fracture toughness estimates from the toughness scatter of the Charpy sized SE(B) specimens in the ductile-to-brittle transition regime. In this regime, according to the ELB and MC methods, SE(B) specimens provide cleavage toughness data, which tend to be non-conservative compared to those of standard C(T) specimens. However, analyses based on the exponential curve fitting method show good agreement between the fracture toughness ...

Energy Technology Data Exchange (ETDEWEB)

The objective of this research project is to investigate the biocompatibility of N-isopropylacrylamide (NIPAAm) monomers and poly(N-isopropylacrylamide) (PNIPAAm) nanoparticles in vitro. PNIPAAm nanoparticles of different sizes were synthesized and characterized by transmission electron microscopy and dynamic light scattering. Cytotoxicity studies using MTS assays were conducted on fibroblasts, smooth muscle cells, and endothelial cells. In addition, the concentration of NIPAAm monomers remaining on PNIPAAm nanoparticles was determined using bromination and spectrophotometry. The cytotoxicity results did not show a significant difference in cell survival when cells were exposed to different particle sizes (100, 300, and 500 nm). Dose studies showed that all three cell types exposed to 100 nm PNIPAAm nanoparticles at concentrations less than or equal to 5 mg/mL were compatible, while cells exposed to NIPAAm monomers exhibited toxicity even at very low ...

Science.gov (United States)

Magnolia bark and ginger rhizome is a drug pair in many prescriptions for treatment of mental disorders in traditional Chinese medicine (TCM). However, compatibility and synergism mechanism of two herbs on antidepressant actions have not been reported. The aim of this study was to approach the rationale of the drug pair in TCM. We evaluated antidepressant-like effects of mixture of honokiol and magnolol (HMM), polysaccharides (PMB) from magnolia bark, essential oil (OGR) and polysaccharides (PGR) from ginger rhizome alone, and the possibility of synergistic interactions in their combinations in the mouse forced swimming test (FST) and tail suspension test (TST). Serotonin (5-HT) and noradrenaline (NE) levels in prefrontal cortex, hippocampus and striatum were also examined. 30 mg/kg HMM decreased immobility in the FST and TST in mice after one- and two-week treatment. OGR (19.5 or 39 mg/kg) alone was ineffective. The combination of an ineffective dose of 39 mg/kg ...

International Nuclear Information System (INIS)

Earlier research by Zel'manov and by Hoenl and Dehnen has shown how the geodesic equation for a charged test particle can be written as a Lorentz force law in which the four-velocity u"i of an observer in the physical three-space #gamma#_#alpha#_#beta# = -g_#alpha#_#beta# + g_0_#alpha# g_0_#beta# / g_0_0 is regarded as a gravitational vector potential. Analysing this analogy further, we write the four ("i_0) components of the Einstein equations in a form resembling a non-linear Maxwell system, which, for a stationary field, is most clearly understood from the Kaluza-Klein perspective, the projection being from four dimensions to three, rather than from five dimensions to four. For the vacuum theory defined by vanishing energy-momentum tensor, T_i_j = 0, these equations exhibit the structure of a non-linear sigma model, found by Ernst, and investigated by Gibbons and Hawking and by Sanchez, the scalar potentials of which we here relate to the gravito-electromagnetic ...

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This report contains information about the effect of frequency on the breakdown voltage of an air gap at standard pressure and temperature, 76 mm Hg and O{degrees}C, respectively. The frequencies of interest are 47 MHz and 60 MHz. Additionally, the breakdown in vacuum is briefly considered. The breakdown mechanism is explained on the basis of collision and ionization. The presence of the positive ions produced by ionization enhances the field in the gap, and thus determines the breakdown. When a low-frequency voltage is applied across the gap, the breakdown mechanism is the same as that caused by the DC or static voltage. However, when the frequency exceeds the first critical value f{sub c}, the positive ions are trapped in the gap, increasing the field considerably. This makes the breakdown occur earlier; in other words, the breakdown voltage is lowered. As the frequency increases two decades or more, the second critical frequency, f{sub ce}, is reached. This time ...

Energy Technology Data Exchange (ETDEWEB)

Improvement in efficiency and profitability of hydrogenation reaction of heavy hydrocarbon resources is the most important matter to be done. In this study, coprocessing of coal and heavy oil vacuum residue was conducted using syngas-water as a hydrogen source. For the investigation of effect of the reaction temperature during the coprocessing of Wandoan coal and Arabian heavy vacuum residue using Fe(CO)5 as a catalyst, the conversion, 66.0% was obtained at 425{degree}C. For the investigation of effect of reaction time, the yield of light fractions further increased during the two stage reaction at 400{degree}C for 60 minutes and at 425{degree}C for 60 minutes. Finally, almost 100% of THF-soluble matter was obtained through the reaction using 2 mmol of Fe(CO)5 catalyst at 400{degree}C for 60 minutes, and hydrogenation of heavy oil was proceeded simultaneously. When comparing coprocessing reactions using three kinds of hydrogen sources, i.e., ...

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A cryocondensation pump was designed for the baffle chamber of General Atomics DIII-D tokamak and will be installed in the fall of 1992. The purpose of the pump is to study plasma density control by pumping the divertor. The pump is toroidally continuous, approximately 10 m long and located in the lower outer corner of the vacuum chamber of the machine. It consists of a 1 m{sup 2} liquid helium-cooled surface surrounded by a liquid nitrogen-cooled shield to limit the heat load on the helium-cooled surface. The liquid nitrogen-cooled surface is surrounded by a radiation/particle shield to prevent energetic particles from impacting and releasing condensed water molecules. A thermal enhancement coating was applied to the nitrogen shell to lower the maximum temperature of the shell. The coating is non-continuous to keep the toroidal electrical resistance high. The whole pump is supported off the water-cooled vacuum vessel wall. Supports for the ...

Energy Technology Data Exchange (ETDEWEB)

Red mud, which is a pollutant residue from the extraction of alumina from bauxite ore, was utilized as an additive to a well blended mixture of three Egyptian clays, feldspar, quartz and grog. This was added in gradual proportions to study its effect on the vitrification properties of fired samples. Samples were moulded under a pressure of 20.7 MPa and fired at temperatures ranging from 950 C to 1100 C for soaking periods up to three hours. Compressive strength was determined as function of percent red mud added and firing temperature. A semi-exponential relation was established between strength and apparent porosity. 50 x 50 mm tiles containing 70% red mud addition and fired at 1100 C for one hour were tested. They were found to match the standards required for glazed wall tiles bodies. Tiles fired at 1100 C for 3 hours were compatible with the standards for glazed floor tiles. (orig.)

Energy Technology Data Exchange (ETDEWEB)

This report covers the progress made on the title project for the project period. Four major areas of inquiry are being pursued. Advanced solid state NMR methods are being developed to assay the distribution of the various important functional groups that determine the reactivity of coals. Special attention is being paid to methods that are compatible with the very high magic angle sample spinning rates needed for operation at the high magnetic field strengths available today. Polarization inversion methods utilizing the difference in heat capacities of small groups of spins are particularly promising. Methods combining proton-proton spin diffusion with {sup 13}C CPMAS readout are being developed to determine the connectivity of functional groups in coals in a high sensitivity relay type of experiment. Additional work is aimed at delineating the role of methyl group rotation in the proton NMR relaxation behavior of coals.

Science.gov (United States)

Simple hydroxamic acids have been shown to have useful applications in an Advanced Purex process for the reprocessing of irradiated nuclear fuel. They are especially suited to the separation of neptunium (IV) from uranium (VI) by the selective formation of a hydrophilic complex with Np(IV). U(VI) extraction in to 30% tributyl phosphate is unaffected. However, they have also been shown to be very fast reducing agents for Np(VI). The timescales of the reduction have been defined under a range of typical Purex Process conditions although the accurate determination of the reaction kinetics was not possible due to the rapidity of the reaction. U(VI) was shown not to be reduced. Therefore, Np(VI) can be efficiently reductively stripped when solvent phase (30% tributyl phosphate in odourless kerosene) solutions of Np(VI) and U(VI) are contacted with aqueous phase hydroxamic acid solutions. The slow reduction of plutonium (IV) to Pu(III) has also been observed and this is apparently enhanced ...

Energy Technology Data Exchange (ETDEWEB)

A couple of domestic institutions have been investigating the application of vitrification technology to treat low- and intermediate-level radioactive wastes in Korea. In the case that such investigations prove to be successful, it is expected that commercial vitrification plants will be constructed. The safety insuring on vitrification plants could not be compatible with criterion on radioactive waste management because the facilities are at high temperature and contain a variety of accommodations for the exhaust gases and residual products. Therefore, it is necessary to suggest a new strategy or modifications of criterion of radioactive waste management on considerations related with the vitrification technology. In order to ensure the safety of vitrification plants, a technical guideline or standard for design and operation of vitrification plants must be established too. A study on the safety assessment of vitrification plants in consideration with general ...

Energy Technology Data Exchange (ETDEWEB)

A system for real-time neutron radiography of moving objects is described. It comprise a source adapted to generate a continuous uninterrupted series of neutron pulses. Each pulse has a predetermined peak power and duration compatible with the framing times of a real-time video imaging system. A transporter moves an object to be examined to bring sequentially position selected portions of the object in the path of the pulses. Where the object itself has moving components, pulses are sequentially incident on the object. According to any dissimilarities, the object will alter the intensity of the neutrons passing therethrough. In order to record separately the changes in the neutron intensity, for each pulse, an imager is positioned to receive the neutron beam pulses which have been altered by their passage through the object and produce images indicating intensity alterations. A refrigerated beryllium filter can be used to effectively eliminate thermal neutrons from ...

CERN Document Server

Extensive investigations have been and are being carried out on a stiff clay from an underground research laboratory located at Mol (Belgium) called Boom clay, in the context of research into deep nuclear waste disposal. Suction effects in deep Boom clay block samples were investigated through the characterisation of the water retention and of the swelling properties of the clay. The data obtained allowed an estimation of the sample initial suction that was reasonably compatible with the in-situ state of stress at a depth of 223 m. The relationship between suction and stress changes during loading and unloading sequences were also examined by running oedometer tests with suction measurements. A rather wide range of the ratio s/sigma 'v (being s the suction and sigma 'v the effective vertical stress) was obtained (0.61 - 1), different from that proposed by Bishop et al; (1974). Finally, the effect of suction release under an isotropic stress close to the estimated ...

British Library Electronic Table of Contents (United Kingdom)

Sm"1"."8Ce"0"."2CuO"4-xCe"0"."9Gd"0"."1O"1"."9"5 (SCC-xCGO, x=0-12vol.%) composite cathodes supported on Ce"0"."9Gd"0"."1O"1"."9"5 (CGO) electrolyte are studied for applications in IT-SOFCs. Results show that Sm"1"."8Ce"0"."2CuO"4 material is chemically compatible with Ce"0"."9Gd"0"."1O"1"."9"5 at 1000^oC. The composite electrode exhibits optimum microstructure and forms good contact with the electrolyte after sintering at 1000^oC for 4h. The polarization resistance (R"p) reduces to the minimum value of 0.17@Wcm^2 at 750^oC in air for SCC-CGO06 composite cathode. The relationship between R"p and oxygen partial pressure indicates that the reaction rate-limiting step is the surface diffusion of the dissociative adsorbed oxygen on the composite cathode.

CERN Document Server

We apply the permutation symmetry S3 to both charged-lepton and neutrino mass matrices, and suggest a useful symmetry-breaking scheme, in which the flavor symmetry is explicitly broken down via S3 -> Z3 -> nothing in the charged-lepton sector and via S3 -> Z2 -> nothing in the neutrino sector. Such a two-stage breaking scenario is reasonable in the sense that both Z3 and Z2 are the subgroups of S3, while Z3 and Z2 only have a trivial subgroup. In this scenario, we can naturally obtain a relatively large value of the smallest neutrino mixing angle, e.g., theta13 ~ 9 degrees, which is compatible with the recent result from T2K experiment and will be precisely measured in the ongoing Double Chooz and Daya Bay reactor neutrino experiments. Moreover, the maximal atmospheric mixing angle theta23 ~ 45 degrees can also be obtained while the best-fit value of solar mixing angle theta12 ~ 34 degrees is assumed, which cannot be achieved in previous S3 symmetry ...