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Sample records for lbl aecr source

  1. Improvements on the LBL AECR source

    SciTech Connect

    Xie, Z.Q.; Lyneis, C.M.

    1995-04-01

    Performance of the LBL AECR source was improved by simultaneously heating the plasma with microwaves of 10 and 14 GHz (two-frequency heating). Plasma stability was improved.and the ion charge state distribution shifted to higher charge state. Production of high charge state ions was increased a factor of 2 to 5 or higher for the very heavy ions such as bismuth and uranium, as compared to the case of single-frequency (14 GHz) heating. Fully stripped argon ions at intensity I {ge} 5 enA were directly identified by the AECR charge state analyzing system for the first time. High charge state ion beams of bismuth and uranium produced by the source were injected into the 88-Inch Cyclotron. After acceleration to energies greater than 6 MeV/nucleon, the extracted beam intensities were 1{times}10{sup 6}pps or higher for Bi{sup 50+,51+} and {sup 238}U{sup 52+,53+}. Tests in the AECR source have also shown Al{sub 2}O{sub 3} coating is an effective coating and a better method than the electron gun for providing cold electrons to the ECR plasma. The AECR source will be upgraded to raise its magnetic field strengths to obtain better plasma confinement and enhanced production of hi ah charge state heavy ions.

  2. Performance of the LBL AECR source at various frequencies

    SciTech Connect

    Xie, Z.Q.; Lyneis, C.M.; Lundgren, S.A.; Collins, D.

    1992-07-01

    To study the effects of frequency on an electron cyclotron resonance (ECR) ion source, the LBL Advanced ECR ion source (designed to operate at 14 GHz) has been tested at 6.4, 10, and 14 GHz with one plasma chamber (ID = 6.0 cm), a permanent sextuple magnet ( closed sextuple'') with a field strength of 0.84 Tesla at the chamber wall, and no radial vacuum pumping. Pure oxygen was used as the running gas for a fair comparison. The source was tested as a single stage, as well as with cold electron injection using an electron gun in place of a conventional microwave-driven first stage. Higher frequency, with a higher axial magnetic field to ensure a closed ECR zone for electron heating, does give better performance. As demonstrated before, at each frequency electron injection led to about a factor of two increase in the high charge state oxygen beam intensity. The 14 GHz performance of the AECR source with the closed sextuple magnet was compared to the slotted sextuple'' (a plasma chamber with radial pumping slots of 7.0-cm dia and a weaker magnet of 0.64 Tesla at the chamber wall). Results show that a stronger sextuple magnet alone does not automatically improve the source performance.

  3. Performance of the LBL AECR source at various frequencies

    SciTech Connect

    Xie, Z.Q.; Lyneis, C.M.; Lundgren, S.A.; Collins, D.

    1992-07-01

    To study the effects of frequency on an electron cyclotron resonance (ECR) ion source, the LBL Advanced ECR ion source (designed to operate at 14 GHz) has been tested at 6.4, 10, and 14 GHz with one plasma chamber (ID = 6.0 cm), a permanent sextuple magnet (``closed sextuple``) with a field strength of 0.84 Tesla at the chamber wall, and no radial vacuum pumping. Pure oxygen was used as the running gas for a fair comparison. The source was tested as a single stage, as well as with cold electron injection using an electron gun in place of a conventional microwave-driven first stage. Higher frequency, with a higher axial magnetic field to ensure a closed ECR zone for electron heating, does give better performance. As demonstrated before, at each frequency electron injection led to about a factor of two increase in the high charge state oxygen beam intensity. The 14 GHz performance of the AECR source with the closed sextuple magnet was compared to the ``slotted sextuple`` (a plasma chamber with radial pumping slots of 7.0-cm dia and a weaker magnet of 0.64 Tesla at the chamber wall). Results show that a stronger sextuple magnet alone does not automatically improve the source performance.

  4. Preliminary performance of the LBL AECR

    SciTech Connect

    Lyneis, C.M.; Xie, Zuqi; Clark, D.J.; Lam, R.S.; Lundgren, S.A.

    1990-11-01

    The AECR source, which operates at 14 GHz, is being developed for the 88-Inch Cyclotron at Lawrence Berkeley Laboratory. The AECR has been under source development since December 1989, when the mechanical construction was completed. The first AECR beams were injected into the cyclotron in June of 1990 and since then a variety of ion species from the AECR have been accelerated. The cyclotron recently accelerated {sup 209}Bi{sup 38+} to 954 MeV. An electron gun, which injects 10 to 150 eV electrons into the plasma chamber of the AECR, has been developed to increase the production of high charge state ions. With the electron gun the AECR has produced at 10 kV extraction voltage 131 e{mu}A of O{sup 7+}, 13 e{mu}A of O{sup 8+}, 17 e{mu}A of Ar{sup 14+}, 2.2 e{mu}A of Kr{sup 25+}, 1 e{mu}A of Xe{sup 31+}, and 0.2 e{mu}A of Bi{sup 38+}. The AECR was also tested as a single stage source with a coating of SiO{sub 2} on the plasma chamber walls. This significantly improved its performance compared to no coating, but direct injection of electrons with the electron gun produced the best results. 5 refs., 6 figs., 4 tabs.

  5. Recent developments on ECR sources at LBL

    SciTech Connect

    Xie, Z.Q.; Lyneis, C.M.

    1993-05-05

    After a number of refinements, the stability and ease of tuning of the LBL AECR ion source are greatly improved. Several nuclear science experiments have now used cyclotron ion beams injected by the AECR ion source and have taken advantage of its good short and long term-stability and high performance. Refinements include installation of a dc filament power supply for the electron gun, improved gas flow control.and temperature stabilization of parts of the microwave transmission network. Measurements of the mean plasma potential and plasma potential difference were made on the AECR and the LBL ECR sources. The absolute. mean potentials of plasmas of oxygen, argon, and argon mixed with oxygen in the AECR have been determined. These plasma potentials are positive with respect to the plasma wall and are on the order of a few tens of volts for microwave power up to 600 W and normal operating gas flow. Electrons injected by an electron gun into the AECR plasma reduce the plasma potentials. Beam energy spreads of oxygen, argon and argon mixed with oxygen have also been measured. Measurement of the plasma potential difference between the first and the second stage of the LBL ECR ion source shows that the plasma potential in the first stage is higher than the second stage. Such plasma potential differences range from about 10 to 200 volts depending on the microwave power and density of neutral atoms. With these potential differences, typically of 10 to 40 V at the LBL ECR running conditions, most of the 1+ ions produced by the first stage are probably not be confined by the second state plasma. Thus it appears that the main function of a microwave-driven first stage is to provide electrons to the second stage plasma, as is done with an electron gun in the AECR source.

  6. Integrating a Traveling Wave Tube into an AECR-U ion source

    SciTech Connect

    Covo, Michel Kireeff; Benitez, Janilee Y.; Ratti, Alessandro; Vujic, Jasmina L.

    2011-07-01

    An RF system of 500W - 10.75 to 12.75 GHz was designed and integrated into the Advanced Electron Cyclotron Resonance - Upgrade (AECR-U) ion source of the 88-Inch Cyclotron at Lawrence Berkeley National Laboratory. The AECR-U produces ion beams for the Cyclotron giving large flexibility of ion species and charge states. The broadband frequency of a Traveling Wave Tube (TWT) allows modifying the volume that couples and heats the plasma. The TWT system design and integration with the AECR-U ion source and results from commissioning are presented.

  7. The LBL advanced light source

    SciTech Connect

    Jackson, A.; Chattopadhyay, S.; Keller, R.; Kim, C.; Nishimura, H.; Selph, F.; Zisman, M.

    1988-06-01

    The LBL Advanced Light Source (ALS) will be a third generation synchrotron radiation facility. It is based on a low emittance 1--2 GeV electron storage ring (natural radial emittance <10 nm-rad), optimized to produce extremely bright beams of electromagnetic radiation (in the energy range from a few eV to around one keV) from insertion devices known as undulators. The storage ring is fed from an injection system consisting of a 50 MeV linac and a 1.5 GeV, 1 Hz, booster synchrotron, which can fill the ring to its normal operating current (400 mA, multibunch, or 7.6 mA, single bunch) in a few minutes. As well as high brightness (which is a consequence of the very small electron beam emittance in the storage ring), the design emphasizes: picosecond timestructure, laserlike coherence properties, narrow bandwidth, and long beam lifetimes. The more familiar continuous synchrotron radiation spectrum will be available from bending magnets and from wiggler magnets. This paper gives a general description of the ALS and discusses some of the significant design issues associated with the low emittance storage ring that is required for this new facility. 7 refs., 6 figs., 2 tabs.

  8. Operating experience with the LBL ECR source

    SciTech Connect

    Lyneis, C.M.

    1987-12-01

    The overall performance of the LBL ECR source in providing beam for the 88-Inch Cyclotron has been excellent. However, during the past two years there have been some fluctuations in the peak performance, particularly for the highest charge states. Among the factors which influence the peak performance are coatings from solid feeds or gases such as SiH/sub 4/ or CO/sub 2/, changes in first stage output, and variation in outgassing rates on the wall. Modifications made to the source have also affected its performance. In the plasma chamber the screens between the sextupole bars were removed to lower its Q/sub 0/. When the 9.2 GHz klystron used to power the first stage failed, it was replaced by a 10.3 GHz klystron. Tests were also made using 6.4 GHz to drive both first and second stages. The source performance in these various configuration will be reviewed.

  9. Vacuum system for the LBL Advanced Light Source (ALS)

    SciTech Connect

    Kennedy, K.; Henderson, T.; Meneghetti, J. )

    1989-03-01

    A 1.5 to 1.9 GeV synchrotron light source is being built at LBL. The vacuum system is designed to permit most synchrotron photons to escape the electron channel and be absorbed in an antechamber. The gas generated by the photons hitting the absorbers in the antechambers will be pumped by titanium sublimation pumps located directly under the absorbers. The electron channel and the antechamber are connected by a 10-mm-high slot that offers good electrodynamic isolation of the two chambers of frequencies affecting the store electron orbit. Twelve 10-meter-long vessels constitute the vacuum chambers for all the lattice magnets. Each chamber will be machined from two thick plates of 5083-H321 aluminum and welded at the perimeter. Machining both the inside and outside of the vacuum chamber permits the use of complex and accurate surfaces. The use of thick plates allows flanges to be machined directly into the wall of each chamber, thus avoiding much welding. 1 ref., 3 figs.

  10. Vacuum system for the LBL advanced light source (ALS)

    SciTech Connect

    Kennedy, K.

    1988-05-01

    A 1.5 to 1.9 GeV synchrotron light source is being built at LBL. The vacuum system is designed to permit all synchrotron photons on the median plane to escape the electron channel and go into an antechamber through a 10 mm high slot. This slot offers effective RF isolation between the electron duct and the antechamber. All unused synchrotron photons within a few mrad of the median plane will be stopped by 96 nearly horizontal absorbers located in the antechamber. The gas, generated by the photons hitting the absorbers, will be directed down to reactive titanium surfaces. Twelve 10 meter long vessels constitute the vacuum chambers for all the lattice magnets. Each chamber will be machined from two thick plates of 5083-H321 aluminum and welded at the perimeter. The nominal wall thickness of the vacuum chamber is 40 mm, which makes it possible to machine a flange into the chamber without the use of welding. 5 refs., 5 figs.

  11. Characterization of the plasma-switch interaction in the LBL HIF ion source

    SciTech Connect

    Hewett, D.W. ); Rutkowski, H.L. )

    1990-01-01

    A new way to characterize the performance of the LBL HIF ion source has been found. In the LBL source, ions are drawn from an arc-generated plasma reservoir in which the electrons are confined by a negative-biased switch'' mesh. Stagnation of the plasma is prevented by absorption of the excess ion flow on this mesh. The ion beam is generated by an external negative voltage that provides Child-Langmuir extraction of the ions through the switch mesh. We elucidate the physics requirements of the source and deduce switch mesh parameters needed for successful operation. 2 refs., 2 figs.

  12. Characterization of the plasma-switch interaction in the LBL HIF ion source

    SciTech Connect

    Hewett, D.W. ); Rutkowski, H.L. )

    1990-12-10

    A new way to characterize the performance of the LBL HIF ion source has been found. In the LBL source, ions are drawn from an arc-generated plasma reservoir in which the electrons are confined by a negative-biased switch'' mesh. Stagnation of the plasma is prevented by absorption of the excess ion flow on this mesh. The ion beam is generated by an external negative voltage that provides Child-Langmuir extraction of the ions through the switch mesh. We elucidate the physics requirements of the source and deduce switch mesh parameters needed for successful operation. 2 refs., 2 figs.

  13. Insertion devices for the Advanced Light Source at LBL

    SciTech Connect

    Hassenzahl, W.; Chin, J.; Halbach, K.; Hoyer, E.; Humphries, D.; Kincaid, B.; Savoy, R.

    1989-03-01

    The Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory will be the first of the new generation of dedicated synchrotron light sources to be put into operation. Specially designed insertion devices will be required to realize the high brightness photon beams made possible by the low emittance of the electron beam. The complement of insertion devices on the ALS will include undulators with periods as short as 3.9 cm and one or more high field wigglers. The first device to be designed is a 5 m long, 5 cm period, hybrid undulator. The goal of very high brightness and high harmonic output imposes unusually tight tolerances on the magnetic field quality and thus on the mechanical structure. The design process, using a generic structure for all undulators, is described. 5 refs., 4 figs., 1 tab.

  14. Measurements and simulations of emittance growth of an H - beam from an LBL volume source

    NASA Astrophysics Data System (ADS)

    Gammel, G.; Ng, Y.; Debiak, T.; Kuehne, F.

    1991-05-01

    Measurements of emittance and emittance growth in an H - beam extracted from an LBL volume source will be presented. Effects of introducing cesium into the arc chamber will be shown. Some differences are noted depending on whether cesium is actively entering the chamber, or whether the source is running on residual Cs. Also, the effect of beam perveance will be shown. At a fixed location, the dependence of emittance on perveance is similar to the dependence of beam width on perveance, as if emittance is proportional to beam divergence. This data will be compared with WOLF simulations of emittance growth at different currents, with a non-uniform initial current density distribution.

  15. ECR heavy-ion source for the LBL 88-inch cyclotron

    SciTech Connect

    Clark, D.J.; Kalnins, J.G.; Lyneis, C.M.

    1983-03-01

    An Electron Cyclotron Resonance (ECR) heavy-ion source is under construction at the LBL 88-Inch Cyclotron. This source will produce very-high-charge-state heavy ions, such as 0/sup 8 +/ and Ar/sup 12 +/, which will increase cyclotron energies by a factor of 2-4, up to A = 80. It is a two-stage source using room-temperature coils, a permanent-magnet sextupole, and a 6-9 GHz microwave system. Design features include adjustable first-to-second-stage plasma coupling, a variable second-stage mirror ratio, high-conductance radial pumping of the second stage, and a beam-diagnostic system. A remotely movable extraction electrode will optimize extraction efficiency. The project includes construction of a transport line and improvements to the cyclotron axial-injection system. The construction period is expected to be two years.

  16. Some novel design features of the LBL metal vapor vacuum arc ion sources

    SciTech Connect

    MacGill, R.A.; Brown, I.G.; Galvin, J.E.

    1989-06-01

    The family of MEVVA (metal vapor vacuum arc) high current metal ion sources developed at LBL over the past several years has grown to include a number of different source versions with a wide range of some of the design and operational parameters. The MicroMEVVA source is a particularly compact version, about 2 cm diameter and 10 cm long, while the MEVVA IV weighs some 30 kG. MEVVAs IV and V incorporate multiple cathode assemblies (16 and 18 separate cathodes, respectively), and the operating cathode can be switched rapidly and without down-time. The new MEVVA V embodiment is quite compact considering its broad beam (10 cm), high voltage (100 kV) and multiple cathode features. The large-area extractor grids used in the MEVVA V were fabricated using a particularly simple technique, and they are clamped into position and so can be changed simply and quickly. The electrical system used to drive the arc is particularly simple and incorporates several attractive features. In this paper we review and describe a number of the mechanical and electrical design features that have been developed for these sources. 9 refs., 5 figs.

  17. The U5.0 undulator design for the advanced light source at LBL

    NASA Astrophysics Data System (ADS)

    Hoyer, E.; Chin, J.; Halbach, K.; Hassenzahl, W.; Humphries, D.; Kincaid, B.; Lancaster, H.; Plate, D.; Savoy, R.

    1990-05-01

    The U5.0 undulator, currently under design, is the first in a series of insertion devices planned for the Advanced Light Source at LBL. U5.0 parameters include a 5-cm period and a 5-m length with an 0.837-T maximum field at a 14-mm gap. A hybrid configuration utilizing NdFeB permanent magnet material and vanadium permendur poles is used for the magnetic structure. Construction is modular with many pole assemblies attached to a pole mount, which in turn is fastened onto one of the backing beams. Vertical field integral correction at the ends is accomplished with permanent magnet rotators. The support structure features a four-post configuration, a rigid base with three kinematic floor supports, and two rigid 5-m long backing beams that fit within the 2.4-m-high accelerator enclosure. The drive system is computer-controlled using a stepper motor and shaft encoder coupled to a roller-screw/nut and chain drive train. Vacuum chamber design is a rigid configuration with a 10 mm vertical by 218 mm horizontal aperture of 5.5 m length. Chamber fabrication features a two-piece welded chamber of 5083 H321 aluminum. Pumping is with ion and titanium sublimation pumps.

  18. The U5. 0 undulator design for the advanced light source at LBL

    SciTech Connect

    Hoyer, E.; Chin, J.; Halbach, K.; Hassenzahl, W.; Humphries, D.; Kincaid, B.; Lancaster, H.; Plate, D.; Savoy, R.

    1989-08-01

    The U5.0 undulator, currently under design, is the first in a series of insertion devices planned for the Advanced Light Source at LBL. U5.0 parameters include a 5 cm period, 5 m length with a 0.837 T maximum field at a 14 mm gap. A hybrid configuration utilizing Nd-Fe-B permanent magnet material and Vanadium Permendur poles is used for the magnetic structure. Construction is modular with many pole assemblies attached to a pole mount, which in turn is fastened onto one of the backing beams. Vertical field integral correction at the ends is with permanent magnet rotators. The supports structure features a 4-post configuration, a rigid base with 3 kinematic floor supports and 2 rigid 5 m long backing beams that fit within the 2.4 m high accelerator enclosure. The drive system is computer controlled utilizing a stepper motor and shaft encode coupled to a roller-screw/nut and chain drive train. Vacuum chamber design is a rigid configuration with a 10 mm vertical by 218 mm horizontal aperture of 5.5 m length. Chamber fabrication features a two-piece welded chamber of 5083 H321 aluminum. Pumping is with ion and titanium sublimation pumps. 5 figs., 1 tab.

  19. Injection system design for the LBL (Lawrence Berkeley Laboratory) 1-2 GeV synchrotron radiation source

    SciTech Connect

    Selph, F.; Jackson, A.; Zisman, M.S.

    1987-03-01

    The injection system for the LBL 1 to 2 GeV Synchrotron Radiation Source is designed to provide an electron beam of 400 mA at 1.5 GeV to the storage ring in a filling time of less than 5 minutes. An alternate mode of operation requires that 7.6 mA be delivered to one, or a few rf bunches in the storage ring. To accomplish these tasks, a high intensity electron gun, a 50 MeV electron linac, and a 1.5 GeV booster synchrotron are used. The performance requirements of the injector complex are summarized. The electron gun and subharmonic buncher, linac design, and linac to booster and booster to storage ring transport are discussed as well as the booster synchrotron. (LEW)

  20. The LBL 1-2 GeV synchrotron radiation source

    SciTech Connect

    Selph, F.B.

    1987-06-01

    The design of the 1 to 2 GeV Synchrotron Radiation Source to be built at the Lawrence Berkeley Laboratory is described. The goal of this facility is to provide very high brightness photon beams in the ultraviolet and soft x-ray regions. The photon energy range to be served is from 0.5 eV to 10 keV, with the brightest beams available in the 1 eV to 1 keV interval. For time-resolved experiments, beam pulses of a few tens of picoseconds will be available. Emphasis will be on the use of undulators and wigglers to produce high quality, intense beams. Initially, four of the former and one of the latter devices will be installed, with six long straight sections left open for future installations. In addition, provision is being made for 48 beamlines from bending magnets. The storage ring is optimized for operation at 1.5 GeV, with a maximum energy of 1.9 GeV. The injection system includes a 1.5 GeV booster synchrotron for full energy injection at the nominal operating energy of the storage ring. Filling time for the maximum storage ring intensity of 400 mA is about 2 minutes, and beam lifetime will be about 6 hours. Attention has been given to the extraordinary requirements for beam stability, and to the need to independently control photon beam alignment. Typical rms beam size in insertion regions is 201 ..mu..m horizontal, and 38 ..mu..m vertical. The manner in which this design achieves very high spectral brightness from undulators and wigglers, while maintaining a modest value for the beam current, will be described. Primarily, this requires that the design of the lattice, the arrangement of bending magnets, focusing quadrupoles and straight sections, be done with this in mind.

  1. Calibration results of the ebit medium-energy flat-field spectrometer using the LBL advanced light source

    SciTech Connect

    Lepson, J K; Beiersdorfer, P; Brown, G V; Chen, H; Gullikson, E M; Schneider, M B; Utter, S B; Wong, K L

    2001-01-17

    The relative instrument response function of a flat-field grating extreme ultraviolet spectrometer was determined using the ALS synchrotron source in the wavelength region 40-200 {angstrom}. Details of the calibration procedure and results are given in the report.

  2. Design, fabrication, and calibration of curved integral coils for measuring transfer function, uniformity, and effective length of LBL ALS (Lawrence Berkeley Laboratory Advanced Light Source) Booster Dipole Magnets

    SciTech Connect

    Green, M.I.; Nelson, D.; Marks, S.; Gee, B.; Wong, W.; Meneghetti, J.

    1989-03-01

    A matched pair of curved integral coils has been designed, fabricated and calibrated at Lawrence Berkeley Laboratory for measuring Advanced Light Source (ALS) Booster Dipole Magnets. Distinctive fabrication and calibration techniques are described. The use of multifilar magnet wire in fabrication integral search coils is described. Procedures used and results of AC and DC measurements of transfer function, effective length and uniformity of the prototype booster dipole magnet are presented in companion papers. 8 refs.

  3. Calculation of collective effects and beam lifetimes for the LBL (Lawrence Berkeley Laboratory) 1-2 GeV synchrotron radiation source

    SciTech Connect

    Chattopadhyay, S.; Zisman, M.S.

    1987-03-01

    In designing a third-generation high brightness synchrotron radiation source, attention must be paid to the various collective effects that can influence beam performance. We report on calculations, performed with the code ZAP, of the bunch length, the transverse emittance and the beam lifetime (from both Touschek and gas scattering) for our 1-2 GeV storage ring. In addition, we estimate the growth times for both longitudinal and transverse coupled bunch instabilities. Bunch lengths of about 20 ps should be obtainable and intrabeam scattering emittance growth is small. For a limiting undulator gap of 1 cm and residual gas pressure of 1n Torr, the beam lifetime is about 5 hours in the single-bunch mode; in the multibunch mode, lifetimes in excess of 6 hours are expected. These results indicate that all performance goals for the facility should be achievable.

  4. Emittance measurements on the LBL ECR source

    SciTech Connect

    Clark, D.J.

    1987-11-01

    Measurements of radial emittance and the upper limit of energy spread have been made using a scanning Faraday cup after a waist, on beams of oxygen, argon and krypton. The general features are that the divergence seen at the scanning cup shows a central core and tails on each side. The un-normalized emittance of the beam core decreases with increasing Q/A in a way that is not explained by simple assumptions about the plasma or extraction system. Data from an experimental 1 mm diameter extraction aperture indicates that plasma density is about the same as over the standard aperture, but that the plasma energy spread is reduced to an upper limit of .2 to .4 V, and beam brightness is up by a factor of 10 for medium charge states. 9 refs., 10 figs., 1 tab.

  5. Multiple beam induction linac research at LBL

    SciTech Connect

    Garvey, T.; Eylon, S.; Fessenden, T.J.; Hahn, K.; Henestroza, E.; Keefe, D.

    1990-06-01

    We present results of progress on the LBL multiple beam induction linac experiment (MBE-4). This machine models the accelerator physics of the electric-focused portion of a driver for heavy ion inertial confinement fusion. Four beams of cesium ions are accelerated in common through twenty four induction gaps while being separately focused in individual electrostatic AG focusing channels. Early experiments have demonstrated current amplification in the linac, from 10 mA to 90 mA per beam. This is achieved both by acceleration (from 200 keV to 1 MeV) and by carefully controlled bunch compression. Recent experiments have concentrated on studies of beams extracted from an ion source which produces 5 mA cesium beams at emittances near 0.03 {pi} mm-mrad (normalized). Experiments and theory show a growth of emittance (by about a factor of 2) as these beams are accelerated through the linac. Results of recent measurements of the transverse emittance behavior of these strongly space-charge-dominated ion beams are reviewed and compared with theory. 9 refs., 3 figs.

  6. Swift observations of IBL and LBL objects

    NASA Astrophysics Data System (ADS)

    Massaro, F.; Giommi, P.; Tosti, G.; Cassetti, A.; Nesci, R.; Perri, M.; Burrows, D.; Gerehls, N.

    2008-10-01

    Context: BL Lacs are an enigmatic class of active galactic nuclei (AGNs), characterized by the non-thermal continuum typically attributed to synchrotron and inverse Compton emission. Depending on the frequency location of the maxima of these components, they are subdivided into three subclasses LBLs, IBLs, and HBLs. We present the results of a set of observations of eight BL Lac objects of LBL and IBL type performed by the XRT and UVOT detectors onboard the Swift satellite between January 2005 and November 2006. Aims: We are mainly interested in measuring the spectral parameters, and particularly the steepness between the UV and the X-ray band, useful for determining the classification of these sources. We compare the behavior of these sources with previous XMM-Newton, BeppoSAX observations and with historical data in the X-ray and in the optical band. We are also interested in classifying the sources in our sample on the basis of the Swift observations and comparing them with their classification presented in literature. Methods: We performed X-ray spectral analysis of observed BL Lac objects using a simple powerlaw and in a few cases the log-parabolic model. We also combined the UV emission with the low energy X-ray data to describe their spectral energy distribution. Results: We used Swift observational data to classify sources in our sample and derived parameters of their spectral energy distribution. Conclusions: We found that for the IBLs X-rays low states show features of the high energy component, usually interpreted as due to inverse Compton emission. Sources in our sample exhibit a range of temporal UV and X-ray behaviors, some objects having clear and neat correlated UV and X-ray variations (e.g. ON231) and other objects showing no clear (e.g. AO 0235+164) UV and X-ray correlation. Finally, we also note that our estimates of spectral curvature are in the range of that measured for the High frequency peaked BL Lac objects (HBLs).

  7. Debittering of Protein Hydrolysates by Lactobacillus LBL-4 Aminopeptidase

    PubMed Central

    Tchorbanov, Bozhidar; Marinova, Margarita; Grozeva, Lydia

    2011-01-01

    Yoghurt strain Lactobacillus LBL-4 cultivated for 8–10 h at pH ~6.0 was investigated as a considerable food-grade source of intracellular aminopeptidase. Cell-free extract manifesting >200 AP U/l was obtained from cells harvested from 1 L culture media. Subtilisin-induced hydrolysates of casein, soybean isolate, and Scenedesmus cell protein with degree of hydrolysis 20–22% incubated at 45°C for 10 h by 10 AP U/g peptides caused an enlarging of DH up to 40–42%, 46–48%, and 38–40% respectively. The DH increased rapidly during the first 4 h, but gel chromatography studies on BioGel P-2 showed significant changes occurred during 4–10 h of enzyme action when the DH increased gradually. After the digestion, the remained AP activity can be recovered by ultrafiltration (yield 40–50%). Scenedesmus protein hydrolysate with DH 20% was inoculated by Lactobacillus LBL-4 cells, and after 72 h cultivation the DH reached 32%. The protein hydrolysates (DH above 40%) obtained from casein and soybean isolate (high Q value) demonstrated a negligible bitterness while Scenedesmus protein hydrolysates (low Q value) after both treatments were free of bitterness. PMID:21876793

  8. INSTRUCTIONS FOR OPERATING LBL FORMALDEHYDE SAMPLER

    SciTech Connect

    Fanning, L.Z.; Allen, J.R.; Miksch, R.R.

    1981-09-01

    The LBL formaldehyde sampler consists of two parts: 1) a pump box and 2) a small refrigerator housing sampling bubblers. The pump box contains two pumps, a timer, a flow controller, an electrical cord, and a ten-foot piece of tubing to connect the refrigerator to the pump box. The small refrigerator contains four columns of bubbler sampling trains attached to a metal plate. Two sampling trains each are plumbed in parallel to two sampling ports on the back of the refrigerator. The two sampling lines supplied are to be attached to these ports to allow two locations to be sampled at once (usually one indoor and one outdoor). The refrigerator also contains a rack for holding bubbler tubes. In the sampling process, air is drawn through a sampling line attached to the fitting at the back of the refrigerator and into a prlmary bubbler containing a trapping solution. This trapping solution can be distilled water or an aqueous solution of some compound that reacts with formaldehyde. From this bubbler the air goes through a second bubbler containing the same trapping solution as the first bubbler. (To maintain sample integrity, all parts that the air sample contacts are made of Teflon, polypropylene, and stainless steel.) The air then goes into the third bubbler, which contains no liquid. This bubbler contains a hypodermic needle that serves as a flow-control orifice. The hypodermic needle, in conjunction with the flow controller in the pump box, ensures a constant a flow rate. The refrigerator contains four columns of these sets of three bubblers. After samples have been collected, the bubbler bottoms are detached and the contents of the first and second bubblers in each column are poured together, capped, and labeled. The use of a refrigerated primary and secondary bubbler whose contents are combined at the end of a sampling period ensures 95% collection efficiency. After the bubbler tubes are capped and labeled, they are stored either in the rack supplied in the

  9. Guidelines for generators of hazardous chemical waste at LBL and Guidelines for generators of radioactive and mixed waste at LBL

    SciTech Connect

    Not Available

    1991-07-01

    The purpose of this document is to provide the acceptance criteria for the transfer of hazardous chemical, radioactive, and mixed waste to Lawrence Berkeley Laboratory's (LBL) Hazardous Waste Handling Facility (HWHF). These guidelines describe how a generator of wastes can meet LBL's acceptance criteria for hazardous chemical, radioactive, and mixed waste. 9 figs.

  10. Triggering the LBL time projection chamber

    SciTech Connect

    Ronan, M.; Millaud, J.; McGathen, T.

    1981-10-01

    A fast digital trigger was built for the LBL Time Projection Chamber (TPC) installed in the PEP-4 detector at SLAC. The TPC is an innovative High Energy Physics detector which will provide particle identification from dE/dx information within the tracking volume. The TPC trigger uses discriminator signals from 2220 dE/dx wire channels to require a track of ionization in the TPC which originates from the colliding beam intersection region. The trigger processing is performed as the ionization drifts onto the proportional wires and is completed 17 ..mu..s after beam crossing. This report describes the basic operation of the TPC detector and its trigger; a pretrigger which uses prompt TPC information from the endcap region; and the electronic implementation. The trigger can be tested with realistic simulated patterns of ionization deposits in the TPC which are stored in local memories. Test results from electronic simulations and first results of a test with cosmic rays are shown.

  11. Transient Beam Dynamics in the LBL 2 MV Injector

    SciTech Connect

    Henestroza, E; Grote, D

    1999-12-07

    A driver-scale injector for the Heavy Ion Fusion Accelerator project has been built at LBL. This machine has exceeded the design goals of high voltage (> 2 MV), high current (> 0.8 A of K{sup +}) and low normalized emittance (< 1 {pi} mm-mr). The injector consists of a 750 keV gun pre-injector followed by an electrostatic quadrupole accelerator (ESQ) which provides strong (alternating gradient) focusing for the space-charge dominated beam, and simultaneously accelerates the ions to 2 MeV. A matching section is being built to match the beam to the electrostatic accelerator ELISE. The gun preinjector, designed to hold up to 1 MV with minimal breakdown risks, consists of a hot aluminosilicate source with a large curved emitting surface surrounded by a thick ''extraction electrode''. During beam turn-on the voltage at the source is biased from a negative potential, enough to reverse the electric field on the emitting surface and avoid emission, to a positive potential to start extracting the beam; it stays constant for about 1 {micro}s, and is reversed to turn-off the emission. Since the Marx voltage applied on the accelerating quadrupoles and the main pre-injector gap is a long, constant pulse (several {micro}s), the transient behavior is dominated by the extraction pulser voltage time profile. The transient longitudinal dynamics of the beam in the injector was simulated by running the Particle in Cell codes GYMNOS and WARP3d in a time dependent mode. The generalization and its implementation in WAIW3d of a method proposed by Lampel and Tiefenback to eliminate transient oscillations in a one-dimensional planar diode will be presented.

  12. Guidelines for generators of hazardous chemical waste at LBL and guidelines for generators of radioactive and mixed waste at LBL

    SciTech Connect

    Not Available

    1991-09-01

    In part one of this document the Governing Documents and Definitions sections provide general guidelines and regulations applying to the handling of hazardous chemical wastes. The remaining sections provide details on how you can prepare your waste properly for transport and disposal. They are correlated with the steps you must take to properly prepare your waste for pickup. The purpose of the second part of this document is to provide the acceptance criteria for the transfer of radioactive and mixed waste to LBL's Hazardous Waste Handling Facility (HWHF). These guidelines describe how you, as a generator of radioactive or mixed waste, can meet LBL's acceptance criteria for radioactive and mixed waste.

  13. Preliminary Ionization Efficiencies of {sup 11}C and {sup 14}O with the LBNL ECR Ion Sources

    SciTech Connect

    Xie, Z.Q.; Cerny, J.; Guo, F.Q.; Joosten, R.; Larimer, R.M.; Lyneis, C.M.; McMahan, P.; Norman, E.B.; O'Neil, J.P.; Powell, J.; Rowe, M.W.; VanBrocklin, H.F.; Wutte, D.; Xu, X.J.; Haustein, P.

    1998-10-05

    High charge states, up to fully stripped {sup 11}C and {sup 14}O ion, beams have been produced with the electron cyclotron resonance ion sources (LBNL, ECR and AECR-U) at Lawrence Berkeley National Laboratory. The radioactive atoms of {sup 11}C and {sup 14}O were collected in batch mode with an LN{sub 2} trap and then bled into the ECR ion sources. Ionization efficiency as high as 11% for {sup 11}C{sup 4+} was achieved.

  14. Reservoir technology research at LBL addressing geysers issues

    SciTech Connect

    Lippmann, M.J.; Bodvarsson, G.S.

    1990-04-01

    The Geothermal Technology Division of the Department of Energy is redirecting a significant part of its Reservoir Technology funding to study problems now being experienced at The Geysers. These include excessive pressure drawdown and associated decline in well flow rates, corrosion due to high chloride concentration in the produced steam and high concentration of noncondensible gases in some parts of the field. Lawrence Berkeley Laboratory (LBL) is addressing some of these problems through field, laboratory and theoretical studies. 11 refs., 6 figs.

  15. LBL/Industry fractured reservoir performance definition project

    SciTech Connect

    Benson, S.M.

    1995-04-01

    One of the problems facing the petroleum industry is the recovery of oil from heterogeneous, fractured reservoirs and from reservoirs that have been partially depleted. In response to this need, several companies, notably British Petroleum USA, (BP) and Continental Oil Company (CONOCO), have established integrated reservoir description programs. Concurrently, LBL is actively involved in developing characterization technology for heterogeneous, fractured rock, mainly for DOE`s Civilian Nuclear Waste Program as well as Geothermal Energy programs. The technology developed for these programs was noticed by the petroleum industry and resulted in cooperative research centered on the petroleum companies test facilities. The emphasis of this work is a tightly integrated interdisciplinary approach to the problem of characterizing complex, heterogeneous earth materials. In this approach we explicitly combine the geologic, geomechanical, geophysical and hydrologic information in a unified model for predicting fluid flow. The overall objective is to derive improved integrated approaches to characterizing naturally fractured gas reservoirs.

  16. Electron beam transport for the LBL IR-FEL

    SciTech Connect

    Staples, J.; Edighoffer, J.; Kim, Kwang-Je

    1992-07-01

    The infrared flee-electron laser (IR-FEL) proposed by LBL as part of the Combustion Dynamics Research Laboratory (CDRL) consists of a multiple-pass accelerator with superconducting cavities supplying a 55 MeV 12 mA beam to an undulator within a 24-meter optical cavity. Future options include deceleration through the same cavities for energy recovery and reducing the power in the beam dump. The electron transport system from the injector through the cavities and undulator must satisfy conditions of high order achromaticity, isochronicity, unity first-order transport matrix around the recirculation loop, variable betatron match into the undulator, ease of operation and economical implementation. This paper presents a workable solution that satisfies these requirements.

  17. Guidelines for Waste Accumulation Areas (WAAs) at LBL. Revision 1

    SciTech Connect

    Not Available

    1994-06-01

    The purpose of this document is to set conditions for establishing and containing areas for the accumulation of hazardous waste at LBL. Areas designed for accumulation of these wastes for up to 90 days in quantities greater than 55 gallons (208 liters) of hazardous waste, one quart (0.946 liter) of extremely hazardous waste, or one quart (0.946 liter) of acutely hazardous waste are called Waste Accumulation Areas (WAAs). Areas designed for accumulation of wastes in smaller amounts are called Satellite Accumulation Areas (SAAs). This document provides guidelines for employee and organizational responsibilities for WAAs, constructing a WAA, storing waste in a WAA, operating and maintaining a WAA, and responding to spills in a WAA.

  18. The 50 MeV Beam Test Facility at LBL

    SciTech Connect

    Leemans, W.; Behrsing, G.; Kim, K.J.; Krupnick, J.; Matuk, C.; Selph, F.; Chattopadhyay, S.

    1993-05-01

    A new beam line, expected to be built by September 1993, will transport the 50 MeV electron beam from the ALS LINAC into an experimental area to support various R&D activities in the Center for Beam Physics at LBL. A variety of experiments are planned involving the interaction of such a relativistic electron beam with plasmas (plasma focusing), laser beams (generation of femtosecond X-ray pulses) and electromagnetic cavities (Crab cavities etc....). The beam line is designed using the measured emittance and Twiss parameters of the ALS linac. It accommodates the different requirements of the various experiments on the electron beam properties (charge, energy, pulse length) and on the handling of the beam before and after the interaction point. Special attention has also been given to incorporate diagnostics for measuring the beam properties (such as the electron energy, bunch length and charge) needed in the interpretation of the experiments.

  19. LBL Magnetic-Measurements Data-Acquisition System

    SciTech Connect

    Green, M.I.; Nelson, D.H.

    1983-03-01

    The LBL Magnetic Measurements Engineering (MME) Group has developed a Real-Time Data Acquisition System (DAS) for magnetic measurements. The design objective was for a system that was versatile, portable, modular, expandable, quickly and easily reconfigurable both in hardware and software, and inexpensive. All objectives except the last were attained. An LSI 11/23 microcomputer is interfaced to a clock-calendar, printer, CRT control terminal, plotter with hard copy, floppy and hard disks, GPIB, and CAMAC buses. Off-the-shelf hardware and software have been used where possible. Operational capabilities include: (1) measurement of high permeability materials; (2) harmonic error analysis of (a) superconducting dipoles and (b) rare earth cobalt (REC) and conventional quadrupole magnets; and (3) 0.1% accuracy x-y mapping with Hall probes. Results are typically presented in both tabular and graphical form during measurements. Only minutes are required to switch from one measurement capability to another. Brief descriptions of the DAS capabilities, some of the special instrumentation developed to implement these capabilities, and planned developments are given below.

  20. AUV Positioning Method Based on Tightly Coupled SINS/LBL for Underwater Acoustic Multipath Propagation

    PubMed Central

    Zhang, Tao; Shi, Hongfei; Chen, Liping; Li, Yao; Tong, Jinwu

    2016-01-01

    This paper researches an AUV (Autonomous Underwater Vehicle) positioning method based on SINS (Strapdown Inertial Navigation System)/LBL (Long Base Line) tightly coupled algorithm. This algorithm mainly includes SINS-assisted searching method of optimum slant-range of underwater acoustic propagation multipath, SINS/LBL tightly coupled model and multi-sensor information fusion algorithm. Fuzzy correlation peak problem of underwater LBL acoustic propagation multipath could be solved based on SINS positional information, thus improving LBL positional accuracy. Moreover, introduction of SINS-centered LBL locating information could compensate accumulative AUV position error effectively and regularly. Compared to loosely coupled algorithm, this tightly coupled algorithm can still provide accurate location information when there are fewer than four available hydrophones (or within the signal receiving range). Therefore, effective positional calibration area of tightly coupled system based on LBL array is wider and has higher reliability and fault tolerance than loosely coupled. It is more applicable to AUV positioning based on SINS/LBL. PMID:26978361

  1. AUV Positioning Method Based on Tightly Coupled SINS/LBL for Underwater Acoustic Multipath Propagation.

    PubMed

    Zhang, Tao; Shi, Hongfei; Chen, Liping; Li, Yao; Tong, Jinwu

    2016-01-01

    This paper researches an AUV (Autonomous Underwater Vehicle) positioning method based on SINS (Strapdown Inertial Navigation System)/LBL (Long Base Line) tightly coupled algorithm. This algorithm mainly includes SINS-assisted searching method of optimum slant-range of underwater acoustic propagation multipath, SINS/LBL tightly coupled model and multi-sensor information fusion algorithm. Fuzzy correlation peak problem of underwater LBL acoustic propagation multipath could be solved based on SINS positional information, thus improving LBL positional accuracy. Moreover, introduction of SINS-centered LBL locating information could compensate accumulative AUV position error effectively and regularly. Compared to loosely coupled algorithm, this tightly coupled algorithm can still provide accurate location information when there are fewer than four available hydrophones (or within the signal receiving range). Therefore, effective positional calibration area of tightly coupled system based on LBL array is wider and has higher reliability and fault tolerance than loosely coupled. It is more applicable to AUV positioning based on SINS/LBL. PMID:26978361

  2. Design overview of a highly stable infrared free electron laser at LBL

    SciTech Connect

    Kim, K.J.; Berz, M.; Chattopadhyay, S.; Gough, R.; Kim, C.; Kung, A.H.; Xie, M. ); Edighoffer, J. ); Stein, W. )

    1990-11-01

    An infrared free electron laser (IRFEL) is being designed for the Chemical Dynamics Research Laboratory (CDRL) at LBL. The FEL is based on a 50 MeV RF linac operating in synchronization to the Advanced Light Source (ALS), and will produce intense (100 {mu}J per micropulse), narrow bandwidth (narrower than 0.1%) radiation between 3 {mu} and 50 {mu}. In the design, we pay particular attention to the FEL stability issues and require that the fluctuations in electron beam energy and in timing be less then 0.05% and 0.1 ps respectively. The FEL spectrum can then be stabilized to about 10{sup {minus}3}, or if grating is used, to 10{sup {minus}4}. We discuss various sources of fluctuations in the gun, the bunchers and the accelerator sections, as well as the feedback and feedforward schemes to reduce these fluctuations. The accelerator structure is chosen to be of the side coupled, standing wave type for easier control. The beam transport is made isochronous to avoid the coupling between the energy and the timing fluctuations. 12 refs., 1 fig.

  3. Requirements and design of a high stable infrared free electron laser at LBL

    SciTech Connect

    Kim, K.J.; Berz, M.; Chattopadhyay, S.; Gough, R.; Kim, C.; Kung, A.H.; Xie, M. ); Edighoffer, J. ); Stein, W. )

    1990-06-01

    An infrared free electron laser (IRFEL) is being designed for the Chemical Dynamics Research Laboratory (CDRL) at LBL. The FEL is based on a 50 MeV RF linac operating in synchronization to the Advanced Light Source (ALS), and will produce intense (100 {mu}J per micropulse), narrow bandwidth (narrower than 0.1%) radiation between 3 {mu} and 50 {mu}. In the design, we pay particular attention to the FEL stability issues and require that the fluctuations in electron beam energy and in timing be less than 0.05% and 0.1 ps, respectively. The FEL spectrum can then be stabilized to about 10{sup {minus}3}, or if grating is used, to 10{sup {minus}4}. We discuss various sources of fluctuations in the gun, the bunchers and the accelerator sections, as well as the feedback and feedforward schemes to reduce these fluctuations. The accelerator structure is chosen to be of the side coupled, standing wave type for easier control. The beam transport is made isochronous to avoid the coupling between the energy and the timing fluctuations. 9 refs., 2 figs.

  4. Report on the 1984 LBL workshop on detectors for relativistic nuclear collisions

    SciTech Connect

    Schroeder, L.S.

    1984-11-01

    Highlights of the Workshop on Detectors for Relativistic Nuclear Collisions, held March 26-30, 1984, at the Lawrence Berkeley Laboratory are reviewed. (Complete proceedings are available as report LBL-18225.) (WHK)

  5. Case study data base companion report 3 to simulation of geothermal subsidence (LBL-10571)

    SciTech Connect

    Miller, I.; Dershowitz, W.; Jones, K.; Myer, L.; Roman, K.; Schauer, M.

    1980-03-01

    The data base developed for selection and evaluation of geothermal subsidence case studies is presented. Data from this data base were used in case studies of Wairakei, The Geysers, and Austin Bayou Prospect (Report LBL 10571).

  6. Spray-assisted layer-by-Layer (LbL) assembly of anisotropic materials

    NASA Astrophysics Data System (ADS)

    de, Souvik; Suarez Martinez, Pilar; Kavarthapu, Avanti; Lutkenhaus, Jodie

    2015-03-01

    Layer-by-layer (LbL) assembly has gained tremendous interest as it allows one to incorporate a large variety of molecules with nano-scale precision and very good reproducibility. In addition to charged polymers, the technique has become extremely popular to fabricate tailor-made thin films containing anisotropic nanomaterials (e.g., graphene oxide sheets). The challenge is that a standard protocol to fabricate ``all-polyelectrolyte'' LbL films may not necessarily give rise to satisfactory film growth when applied to LbL assembly where one of the adsorbing components is an anisotropic nanomaterial. Therefore, in this contribution, we combine polymers and anisotropic nanomaterials via dip- and spray-assisted LbL assembly and investigate the effect of charge density, exfoliation, concentration etc. of the components on the growth behavior and the film quality. The end result is a conformal, pin-hole free coating on model substrates (glass, silicon, metal) over a large area.

  7. pH-indicators doped polysaccharide LbL coatings for hazardous gases optical sensing.

    PubMed

    Mironenko, A Yu; Sergeev, A A; Voznesenskiy, S S; Marinin, D V; Bratskaya, S Yu

    2013-01-30

    Sensitive layer-by-layer (LbL) coatings for optical detection of gaseous NH(3) and HCl were prepared by self-assembly of oppositely charged polysaccharides (chitosan and λ-carrageenan) followed by doping LbLs with pH-sensitive dyes - bromothymol blue (BTB) and Congo red (CR). It has been shown that CR, being an amphoteric dye, diffuses into LbL films regardless of the charge of the outermost polyelectrolyte layer, and the dye loading increases linearly with the LbL film thickness, whereas BTB diffuses into LbL films only when the outermost layer is positively charged, and linearity between dye loading and film thickness holds only up to 8-12 double layers (DLs) deposited. Formation of dye-doped LbL coatings at the surface of K(+)/Na(+) ion-exchanged glass has allowed fabrication of composite optical waveguide (OWG) gas sensor for detection of ammonia and hydrochloric acid vapors. The response time of BTB-doped composite OWG for ammonia detection was below 1s, and the detection limit was below 1 ppm. CR-doped OWG sensors have shown high sensitivity to HCl vapor but slow relaxation time (up to several hours for 12 DL LbL films). PMID:23218366

  8. Composite Layer-by-Layer (LBL) assembly with inorganic nanoparticles and nanowires.

    PubMed

    Srivastava, Sudhanshu; Kotov, Nicholas A

    2008-12-01

    New assembly techniques are required for creating advanced materials with enough structural flexibility to be tuned for specific applications, and to be practical, the techniques must be implemented at relatively low cost. Layer-by-layer (LBL) assembly is a simple, versatile, and significantly inexpensive approach by which nanocomponents of different groups can be combined to coat both macroscopically flat and non-planar (e.g., colloidal core-shell particles) surfaces. Compared with other available assembly methods, LBL assembly is simpler and more universal and allows more precise thickness control at the nanoscale. LBL can be used to combine a wide variety of species--including nanoparticles (NPs), nanosheets, and nanowires (NWs)--with polymers, thus merging the properties of each type of material. This versatility has led to recent exceptional growth in the use of LBL-generated nanocomposites. This Account will focus on the materials and biological applications of introducing inorganic nanocrystals into polymer thin films. Combining inorganic NPs and NWs with organic polymers allows researchers to manipulate the unique properties in the nanomaterial. We describe the LBL assembly technique for introducing metallic NPs into polymers in order to generate a material with combined optomechanical properties. Similarly, LBL assembly of highly luminescent semiconductor NPs like HgTe or CdTe with poly(diallyldimethylammonium chloride) (PDDA) was used to create uniform optical-quality coatings made on optical fibers and tube interiors. In addition, LBL assembly with inorganic nanosheets or clay molecules is reported for fabricating films with strong mechanical and ion transport properties, and the technique can also be employed to prepare Au/TiO(2) core/sheath NWs. The LBL approach not only will be useful for assembly of inorganic nanocrystals with various polymers but can be further applied to introduce specific functions. We discuss how the expanded use of NWs and

  9. Guidelines for generators of hazardous chemical waste at LBL and guidelines for generators of radioactive and mixed waste at LBL. Revision 1

    SciTech Connect

    Not Available

    1991-09-01

    In part one of this document the Governing Documents and Definitions sections provide general guidelines and regulations applying to the handling of hazardous chemical wastes. The remaining sections provide details on how you can prepare your waste properly for transport and disposal. They are correlated with the steps you must take to properly prepare your waste for pickup. The purpose of the second part of this document is to provide the acceptance criteria for the transfer of radioactive and mixed waste to LBL`s Hazardous Waste Handling Facility (HWHF). These guidelines describe how you, as a generator of radioactive or mixed waste, can meet LBL`s acceptance criteria for radioactive and mixed waste.

  10. LBL Research on the Geysers: Conceptual Models, Simulation and Monitoring Studies

    SciTech Connect

    Bodvarsson, G.S.; Lippmann, M.J.; Majer, E.L.; Pruess, K.

    1992-03-24

    As part of The Geysers research activities of DOE's Geothermal Reservoir Technology Program, LBL, in close cooperation with industry, is performing fundamental and applied studies of vapor-dominated geothermal systems. These studies include the development of new methods for evaluating cold water injection, monitoring of the seismic activity in The Geysers associated with injection and production, interpretation of pressure and geochemical changes measured during well tests and long-term production and injection operations, and improvement of existing models of the geothermal system. A review is given of the latest results of DOE-sponsored LBL reservoir engineering and seismic studies relevant to The Geysers.

  11. LBL research on The Geysers: Conceptual models, simulation and monitoring studies

    SciTech Connect

    Bodvarsson, G.S.; Lippmann, M.J.; Majer, E.L.; Pruess, K.

    1982-03-01

    As part of The Geysers research activities of DOE`s Geothermal Reservoir Technology Program, LBL, in close co-operation with industry, is performing fundamental and applied studies of vapor- dominated geothermal systems. These studies include the development of new methods for evaluating cold water injection, monitoring of the seismic activity in The Geysers associated with injection and production, interpretation of pressure and geochemical changes measured during well tests and long-term production and injection operations, and improvement of existing models of the geothermal system. A review is given of the latest results of DOE-sponsored LBL reservoir engineering and seismic studies relevant to The Geysers.

  12. LBL research on The Geysers: Conceptual models, simulation and monitoring studies

    SciTech Connect

    Bodvarsson, G.S.; Lippmann, M.J.; Majer, E.L.; Pruess, K.

    1992-03-01

    As part of The Geysers research activities of DOE's Geothermal Reservoir Technology Program, LBL, in close co-operation with industry, is performing fundamental and applied studies of vapor- dominated geothermal systems. These studies include the development of new methods for evaluating cold water injection, monitoring of the seismic activity in The Geysers associated with injection and production, interpretation of pressure and geochemical changes measured during well tests and long-term production and injection operations, and improvement of existing models of the geothermal system. A review is given of the latest results of DOE-sponsored LBL reservoir engineering and seismic studies relevant to The Geysers.

  13. 75 FR 64691 - Information Collection; Land Between The Lakes (LBL) Communication Effectiveness Study

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-20

    ... Effectiveness Study AGENCY: Forest Service, USDA. ACTION: Notice; request for comment. SUMMARY: In accordance... Effectiveness Study. DATES: Comments must be received in writing on or before December 20, 2010 to be assured of... (LBL) Communication Effectiveness Study. OMB Number: 0596--NEW. Type of Request: NEW. Abstract:...

  14. Volume H/sup -/ ion production experiments at LBL

    SciTech Connect

    Leung, K.N.; Ehlers, K.W.

    1983-11-01

    H/sup -/ ions formed by volume processes have been extracted from a multicusp ion source. It is shown that a permanent magnet filter together with a small positive bias voltage on the plasma grid can produce a very significant reduction in electron drain as well as a sizable increase in H/sup -/ ions available for extraction. A further reduction in electron current is achieved by installing a pair of small magnets at the extraction aperture. An H/sup -/ ion current density of 38 mA/cm/sup 2/ was obtained with a discharge current of approximately 350 A. Different techniques to increase the H/sup -/ ion yield have also been investigated.

  15. Survey and Alighment for the ALS Project at LBL Berkeley

    SciTech Connect

    Keller, R.; Lauritzen, T.; Friedsam, H.; /SLAC

    2005-08-12

    The Advanced Light Source (ALS), now under construction at Lawrence Berkeley Laboratory, is a synchrotron radiation source of the third generation designed to produce extremely bright photon beams in the UV and soft X-ray regions. Its main accelerator components are a 1-1.9 GeV electron storage ring with 196.8 m circumference and 12 super-periods, a 1.5 GeV booster synchrotron with 75.0 m circumference and 4 super-periods, and a 50 MeV linac, as shown in Fig. 1. The storage ring has particularly tight positioning tolerances for lattice magnets and other components to assure the required operational characteristics. The general survey and alignment concept for the ALS is based on a network of fixed monuments installed in the building floor, to which all component positions are referred. Measurements include electronic distance measurements and separate sightings for horizontal and vertical directions, partially with automated electronic data capture. Most of the data processing is accomplished by running a customized version of PC-GEONET. It provides raw data storage, data reduction, and the calculation of adjusted coordinates, as well as an option for error analysis. PC-GEONET has also been used to establish an observation plan for the monuments and calculate their expected position accuracies, based on approximate coordinates. Additionally, for local survey tasks, the commercial software package ECDS is used. In this paper, the ALS survey and alignment strategy and techniques are presented and critically discussed. First experiences with the alignment of the linac and booster components are described.

  16. Preparation of Simulated LBL Defects for Round Robin Experiment

    SciTech Connect

    Gerczak, Tyler J.; Baldwin, Charles A.; Hunn, John D.; Montgomery, Fred C.

    2015-12-01

    A critical characteristic of the TRISO fuel design is its ability to retain fission products. During reactor operation, the TRISO layers act as barriers to release of fission products not stabilized in the kernel. Each component of the TRISO particle and compact construction plays a unique role in retaining select fission products, and layer performance is often interrelated. The IPyC, SiC, and OPyC layers are barriers to the release of fission product gases such as Kr and Xe. The SiC layer provides the primary barrier to release of metallic fission products not retained in the kernel, as transport across the SiC layer is rate limiting due to the greater permeability of the IPyC and OPyC layers to many metallic fission products. These attributes allow intact TRISO coatings to successfully retain most fission products released from the kernel, with the majority of released fission products during operation being due to defective, damaged, or failed coatings. This dominant release of fission products from compromised particles contributes to the overall source term in reactor; causing safety and maintenance concerns and limiting the lifetime of the fuel. Under these considerations, an understanding of the nature and frequency of compromised particles is an important part of predicting the expected fission product release and ensuring safe and efficient operation.

  17. Scintillator characterization using the LBL Pulsed X-ray Facility

    SciTech Connect

    Moses, W.W.; Derenzo, S.E.; Weber, M.J.; Blankespoor, S.C.; Ho, M.H.; West, A.C.

    1994-10-01

    The authors have developed a bench-top pulsed x-ray system for measuring scintillation properties of compounds in crystal or powdered form. The source is a light-excited x-ray tube that produces 40 x-ray photons (mean energy 18.5 keV) per steradian in each 100 ps fwhm pulse. The repetition rate is adjustable from 0 to 10{sup 7} pulses per second. The fluorescent emanations from the x-ray excited samples are detected with either a sapphire-windowed microchannel plate photomultiplier tube (spectral range 150--650 nm, transit time jitter 40 ps fwhm) or a quartz windowed GaAs(Cs) photomultiplier tube (spectral range 160--930 nm, transit time jitter 4 ns fwhm). Decay time spectra are acquired using a TDC Havina 40 ps fwhm resolution over a 84 ms dynamic range. A computer controlled monochromator can be inserted into the optical path to measure the emission spectrum or wavelength resolved decay time spectrum. A computer controlled sample changer allows up to 64 samples to be measured without intervention.

  18. Spatio-temporal control of LbL films for biomedical applications: from 2D to 3D

    PubMed Central

    Monge, Claire; Almodóvar, Jorge; Boudou, Thomas; Picart, Catherine

    2015-01-01

    Introduced in the 90’s by Prof Moehwald, Lvov and Decher, the layer-by-layer (LbL) assembly of polyelectrolytes has become a popular technique to engineer various types of objects such as films, capsules and free standing membranes, with an unprecedented control at the nanometer and micrometer scales. The LbL technique allows to engineer biofunctional surface coatings, which may be dedicated to biomedical applications in vivo but also to fundamental studies and diagnosis in vitro. Initially mostly developed as 2D coatings and hollow capsules, the range of complex objects created by the LbL technique has greatly expanded in the past 10 years. In this review, our aim was to highlight the recent progress in the field of LbL films for biomedical applications and discuss the various ways to control spatially and temporally the biochemical and mechanical properties of multilayers. In particular, we will discuss three major developments of LbL films: 1) the new methods and templates to engineer LbL films and control cellular processes from adhesion to differentiation, 2) the major ways to achieve temporal control by chemical, biological and physical triggers and, 3) the combinations of LbL technique, cells and scaffolds for repairing 3D tissues, including cardio-vascular devices, bone implants and neuro-prosthetic devices. PMID:25627563

  19. Studies at LBL's Bevalac will help resolve uncertainties about radiation risks to astronauts

    SciTech Connect

    Kahn, J.

    1991-01-01

    Plans to operate the LBL's Bevalac facility for space research are discussed. The proposed program includes the use of cell cultures and animal models to assess the biological consequences of exposures to different particles that are components of the space radiation environment. Research will also be conducted on measures to counter radiation. Experiments will be carried out to examine how various materials that could be used in a spacecraft wall would alter the cascade of particles that would ultimately reach an astronaut.

  20. LbL multilayer capsules: recent progress and future outlook for their use in life sciences

    NASA Astrophysics Data System (ADS)

    Del Mercato, Loretta L.; Rivera-Gil, Pilar; Abbasi, Azhar Z.; Ochs, Markus; Ganas, Carolin; Zins, Inga; Sönnichsen, Carsten; Parak, Wolfgang J.

    2010-04-01

    In this review we provide an overview of the recent progress in designing composite polymer capsules based on the Layer-by-Layer (LbL) technology demonstrated so far in material science, focusing on their potential applications in medicine, drug delivery and catalysis. The benefits and limits of current systems are discussed and the perspectives on emerging strategies for designing novel classes of therapeutic vehicles are highlighted.

  1. Biomimetic LBL structured nanofibrous matrices assembled by chitosan/collagen for promoting wound healing.

    PubMed

    Huang, Rong; Li, Wangzhou; Lv, Xiaoxing; Lei, Zhanjun; Bian, Yongqian; Deng, Hongbing; Wang, Hongjun; Li, Jinqing; Li, Xueyong

    2015-06-01

    This paper reports the fabrication of biomimetic nanofibrous matrices via co-electrospinning of polycaprolactone (PCL)/cellulose acetate (CA) and layer-by-layer self-assembly (LBL) of positively charged chitosan (CS) and negatively charged Type Ⅰ collagen on the nanofibrous matrix. FE-SEM images indicate that the average fiber diameter increased from 392 to 541 nm when the coating bilayers varied from 5 to 20.5. Besides, the excellent biocompatibility and enhanced attachment and spreading of normal human dermal fibroblasts (NHDFs) of prepared nanofibrous mats are confirmed by MTT and SEM results. Furthermore, the LBL structured (CS/collagen)n nanofibrous mats greatly improve the cell migration in vitro, promote re-epithelialization and vascularization in vivo, and up-regulate the expression of collagen Ⅳ and α-tubulin, as well as the Integrin β1 and phosphorylation of focal adhesion kinase (FAK) at Tyr-397. The levels of expressed protein are significantly enhanced with increasing coating bilayers via immunohistochemistry and western blotting analyses. Collectively, these results suggest that the LBL structured biomimetic nanofibrous matrices may enhance cell migration and further promote the skin regeneration by up-regulating the secretion of ECM protein and triggering Integrin/FAK signaling pathway, which demonstrate the potential use of the nanofibrous mats to rapidly restore the structural and functional properties of wounded skin. PMID:25890707

  2. Bimodal Tumor-Targeting from Microenvironment Responsive Hyaluronan Layer-by-Layer (LbL) Nanoparticles

    PubMed Central

    2015-01-01

    Active targeting of nanoscale drug carriers can improve tumor-specific delivery; however, cellular heterogeneity both within and among tumor sites is a fundamental barrier to their success. Here, we describe a tumor microenvironment-responsive layer-by-layer (LbL) polymer drug carrier that actively targets tumors based on two independent mechanisms: pH-dependent cellular uptake at hypoxic tumor pH and hyaluronan-directed targeting of cell-surface CD44 receptor, a well-characterized biomarker for breast and ovarian cancer stem cells. Hypoxic pH-induced structural reorganization of hyaluronan-LbL nanoparticles was a direct result of the nature of the LbL electrostatic complex, and led to targeted cellular delivery in vitro and in vivo, with effective tumor penetration and uptake. The nanoscale drug carriers selectively bound CD44 and diminished cancer cell migration in vitro, while co-localizing with the CD44 receptor in vivo. Multimodal targeting of LbL nanoparticles is a powerful strategy for tumor-specific cancer diagnostics and therapy that can be accomplished using a single bilayer of polyamine and hyaluronan that, when assembled, produce a dynamic and responsive cell–particle interface. PMID:25100313

  3. Investigating the Impact of Land between the Lakes (LBL) and Land Use/Land Cover Change on Precipitation Patterns

    NASA Astrophysics Data System (ADS)

    Degu, A. M.; Hossain, F.

    2012-12-01

    Large dams/reservoirs as open water surface and as a mechanism of triggering land use/land cover changes in their vicinity have impacted local climate and extreme precipitation patterns as study show. Urbanization, agricultural development, and forestation are some of the Land Use/Land Cover Changes (LULCC) that are result of development of large dams/reservoirs. Thus creating heterogeneities. It is believed that such heterogeneities bring about a boundary of different air masses that triggers convection due to differential heating as well as variation in soil moisture. One such heterogeneities is of the Land Between the Lakes (LBL). LBL is an inland peninsula formed by Lake Kentucky on Tennessee River and Lake Barkley on Cumberland River in Western Kentucky. The development of the two lakes brought about an area of 680 sq.km forest cover. The LBL renders unique land use/land cover heterogeneities with in a shorter distance providing open water for evaporation and forest for evapotranspiration. Reports as well as a preliminary investigation of nearby weather radar data showed storms dying out as it approaches the inland peninsula and gaining strength east of LBL. The storm exhibits a wave like strength, attenuating before LBL and gaining strength after. The purpose of this study mainly is to investigate the impact of LBL and in general LULCC on precipitation in the area. In this study the following specific scientific question will be addressed a. Has the development of LBL modified precipitation in the region? b. Which LULCC predominately affects storm formation? Summer radar reflectivity data from Paducah, KY station along with North America Regional Reanalysis (NARR) geopotential height and wind direction data will be analyzed for identification of LBL effect precipitation and synoptic effect precipitation, respectively. A Weather Research and Forecasting Model (WRF) will be setup to investigate what land use/land cover predominately modifies precipitation in

  4. Effect of manufacturing errors on field quality of the LBL SSC dipoles

    SciTech Connect

    Meuser, R.B.

    1984-01-01

    A method is developed for determining the field aberrations resulting from specific kinds of manufacturing errors. This method is applied to the 40-mm i.d. dipoles under consideration at LBL, and also to similar ones with 30 and 50 mm i.d. The method is also applied to the CBA and Doubler/Saver magnets and the results compared with the measurements. The results obtained by this method are also compared with those obtained by assigning identical errors to the positions of the edges of all the coil sectors.

  5. Layer-by-Layer (LBL) Self-Assembled Biohybrid Nanomaterials for Efficient Antibacterial Applications.

    PubMed

    Wu, Yuanhao; Long, Yubo; Li, Qing-Lan; Han, Shuying; Ma, Jianbiao; Yang, Ying-Wei; Gao, Hui

    2015-08-12

    Although antibiotics have been widely used in clinical applications to treat pathogenic infections at present, the problem of drug-resistance associated with abuse of antibiotics is becoming a potential threat to human beings. We report a biohybrid nanomaterial consisting of antibiotics, enzyme, polymers, hyaluronic acid (HA), and mesoporous silica nanoparticles (MSNs), which exhibits efficient in vitro and in vivo antibacterial activity with good biocompatibility and negligible hemolytic side effect. Herein, biocompatible layer-by-layer (LBL) coated MSNs are designed and crafted to release encapsulated antibiotics, e.g., amoxicillin (AMO), upon triggering with hyaluronidase, produced by various pathogenic Staphylococcus aureus (S. aureus). The LBL coating process comprises lysozyme (Lys), HA, and 1,2-ethanediamine (EDA)-modified polyglycerol methacrylate (PGMA). The Lys and cationic polymers provided multivalent interactions between MSN-Lys-HA-PGMA and bacterial membrane and accordingly immobilized the nanoparticles to facilitate the synergistic effect of these antibacterial agents. Loading process was characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), and X-ray diffraction spectroscopy (XRD). The minimal inhibition concentration (MIC) of MSN-Lys-HA-PGMA treated to antibiotic resistant bacteria is much lower than that of isodose Lys and AMO. Especially, MSN-Lys-HA-PGMA exhibited good inhibition for pathogens in bacteria-infected wounds in vivo. Therefore, this type of new biohybrid nanomaterials showed great potential as novel antibacterial agents. PMID:26192024

  6. The effect of polysaccharide types on adsorption properties of LbL assembled multilayer films.

    PubMed

    Xu, Jie; Yang, Lixing; Hu, Xiaoxia; Xu, Shimei; Wang, Jide; Feng, Shun

    2015-03-01

    Three types of biocompatible films were fabricated via electrostatic layer-by-layer (LbL) adsorption of oppositely charged cationic polyurethane and anionic polysaccharides with different primary structures, including sodium hyaluronate, sodium carboxymethyl cellulose and sodium alginate. The adsorption behaviors of films were investigated by using the cationic dye methylene blue (MB) as a model drug at various pH values and salt concentrations. The relationship between the type of polysaccharide and the adsorption behavior of LbL films was comparatively studied. It was found that the adsorption capacity increased with an increase of the initial concentration of MB in the concentration range of the experiment to all of the films, and the pH of environment ranged from 3.0 to 9.0. The Langmuir equation fit perfectly to the experiment data. In addition, a pseudo second-order adsorption model can well describe the adsorption behaviors of MB for three films. The results showed that the type of side chains and the charge density of the polysaccharides played key roles in the adsorption properties of the PU/polysaccharide multilayer films. PMID:25609027

  7. LBL/JSU/AGMUS science consortium annual report, FY 1991--1992

    SciTech Connect

    Not Available

    1992-12-31

    In 1983, a formal Memorandum of Understanding joined the Ana G. Mendez University System (AGMUS), Jackson State University (JSU), and the Lawrence Berkeley Laboratory (LBL) in a consortium designed to advance the science and technology programs of JSU and AGMUS. This is the first such collaboration between a Hispanic university system, a historically Black university, and a national laboratory. The goals of this alliance are basic and direct: to develop and effect a long-term, comprehensive program that will enable the campuses of AGMUS and JSU to provide a broad, high-quality offering in the natural and computer sciences, to increase the number of minority students entering these fields, and to contribute to scientific knowledge and the federal government`s science mission through research. This report documents the progress toward these goals and includes individual success stories. The LBL/JSU/AGMUS Science Consortium has developed plans for utilizing its program successes to help other institutions to adopt or adapt those elements of the model that have produced the greatest results. Within the five-year plan formulated in 1990 are eight major components, each with defining elements and goals. These elements have become the components of the Science Consortium`s current plan for expansion and propagation.

  8. Direct-Write Maskless Lithography of LBL Nanocomposite Films and its Prospects for MEMS Technologies

    PubMed Central

    Bai, Yongxiao; Ho, Szushen; Kotov, Nicholas A.

    2012-01-01

    Application of nanocomposites in MEMS, flexible electronics, and biomedical devices is likely to demonstrate new performance standards and resolve a number of difficult technical problems enabled by the unique combinations of electrical, optical, and mechanical properties. This study explores the possibility of making microscale nanocomposite patterns using the fusion of two highly versatile techniques: direct-write maskless UV patterning and layer-by-layer assembly (LBL). Together they can be applied to production of a wide variety of nanostructured coatings with complex patterns. Single-walled carbon nanotube (SWNT) and gold nanoparticle LBL nanocomposites assembled with chitosan (CH) were made into prototypical patterns such as concentric helices and bus-line-and-stimulation pads (BLASP) used in flexible antennas and neuroprosthetic devices. The spatial resolution of the technique was established with the standard line grids to be at least 1μm. Gold nanoparticle films revealed better accuracy and higher resolution in direct-write patterning than SWNT composites possibly due to the granular rather than fibrous nature of the composites. The conductivity of the patterned composites was 6.45×10−5 Ω·m and 3.80×10−6 Ω·m at 20°C for nanotube and nanoparticle composites, respectively; in both cases it exceeds electrical parameters of similar composites. Fundamental and technological prospects of nanocomposite MEMS devices in different areas including implantable biomedical, sensing, and optical devices are discussed. PMID:22740054

  9. Electron beam transport for the LBL IR-FEL. [Infrared free-electron laser

    SciTech Connect

    Staples, J.; Edighoffer, J.; Kim, Kwang-Je.

    1992-07-01

    The infrared flee-electron laser (IR-FEL) proposed by LBL as part of the Combustion Dynamics Research Laboratory (CDRL) consists of a multiple-pass accelerator with superconducting cavities supplying a 55 MeV 12 mA beam to an undulator within a 24-meter optical cavity. Future options include deceleration through the same cavities for energy recovery and reducing the power in the beam dump. The electron transport system from the injector through the cavities and undulator must satisfy conditions of high order achromaticity, isochronicity, unity first-order transport matrix around the recirculation loop, variable betatron match into the undulator, ease of operation and economical implementation. This paper presents a workable solution that satisfies these requirements.

  10. AUV Underwater Positioning Algorithm Based on Interactive Assistance of SINS and LBL.

    PubMed

    Zhang, Tao; Chen, Liping; Li, Yao

    2015-01-01

    This paper studies an underwater positioning algorithm based on the interactive assistance of a strapdown inertial navigation system (SINS) and LBL, and this algorithm mainly includes an optimal correlation algorithm with aided tracking of an SINS/Doppler velocity log (DVL)/magnetic compass pilot (MCP), a three-dimensional TDOA positioning algorithm of Taylor series expansion and a multi-sensor information fusion algorithm. The final simulation results show that compared to traditional underwater positioning algorithms, this scheme can not only directly correct accumulative errors caused by a dead reckoning algorithm, but also solves the problem of ambiguous correlation peaks caused by multipath transmission of underwater acoustic signals. The proposed method can calibrate the accumulative error of the AUV position more directly and effectively, which prolongs the underwater operating duration of the AUV. PMID:26729120

  11. AUV Underwater Positioning Algorithm Based on Interactive Assistance of SINS and LBL

    PubMed Central

    Zhang, Tao; Chen, Liping; Li, Yao

    2015-01-01

    This paper studies an underwater positioning algorithm based on the interactive assistance of a strapdown inertial navigation system (SINS) and LBL, and this algorithm mainly includes an optimal correlation algorithm with aided tracking of an SINS/Doppler velocity log (DVL)/magnetic compass pilot (MCP), a three-dimensional TDOA positioning algorithm of Taylor series expansion and a multi-sensor information fusion algorithm. The final simulation results show that compared to traditional underwater positioning algorithms, this scheme can not only directly correct accumulative errors caused by a dead reckoning algorithm, but also solves the problem of ambiguous correlation peaks caused by multipath transmission of underwater acoustic signals. The proposed method can calibrate the accumulative error of the AUV position more directly and effectively, which prolongs the underwater operating duration of the AUV. PMID:26729120

  12. Transverse distribution of beam current oscillations of a 14 GHz electron cyclotron resonance ion source.

    PubMed

    Tarvainen, O; Toivanen, V; Komppula, J; Kalvas, T; Koivisto, H

    2014-02-01

    The temporal stability of oxygen ion beams has been studied with the 14 GHz A-ECR at JYFL (University of Jyvaskyla, Department of Physics). A sector Faraday cup was employed to measure the distribution of the beam current oscillations across the beam profile. The spatial and temporal characteristics of two different oscillation "modes" often observed with the JYFL 14 GHz ECRIS are discussed. It was observed that the low frequency oscillations below 200 Hz are distributed almost uniformly. In the high frequency oscillation "mode," with frequencies >300 Hz at the core of the beam, carrying most of the current, oscillates with smaller amplitude than the peripheral parts of the beam. The results help to explain differences observed between the two oscillation modes in terms of the transport efficiency through the JYFL K-130 cyclotron. The dependence of the oscillation pattern on ion source parameters is a strong indication that the mechanisms driving the fluctuations are plasma effects. PMID:24593488

  13. Experimental reestablishment of red wolves (Canis rufus) on the Tennessee Valley Authority's Land Between the Lakes (LBL)

    SciTech Connect

    Carley, C.J.; Mechler, J.L.

    1983-10-01

    For all practical purposes the red wolf (Canis rufus) is extirpated in its final range in southeast Texas and southwest Louisiana. Although the species can be preserved in captivity, the only means by which it can be preserved as a naturally occurring element of our national heritage is to reestablish viable populations within the wolf's historic range in the southeastern United States. This proposal outlines a suggested procedure for reestablishing red wolves at Land Between The Lakes (LBL) by initially releasing five adult mated pairs of animals on the area over a two-year period. Recommendations for additions, changes, and deletions to this proposal have been received from the Kentucky Department of Fish and Wildlife Resources, Tennessee Wildlife Resources Agency, other governmental agencies, and interested organizations and individuals in the surrounding area. This proposal includes information describing probable environmental impacts associated with the experimental reestablishment of red wolves at LBL. 39 references, 16 figures, 6 tables.

  14. Femtosecond X-ray generation through 90{sup o} Thomson scattering: Status of the LBL experiment

    SciTech Connect

    Leemans, W.; Schoenlein, R.; Chin, A.; Glover, E.; Conde, M.; Chattopadhyay, S.; Kim, K.J.; Shank, C.V.

    1994-11-01

    Scattering of femotosecond laser pulses off a low energy relativistic electron beam at 90{sup o} offers the possibility to generate ultrashort X-ray pulses. Experiments are under preparation in the Beam Test Facility of the Center for Beam Physics at LBL to demonstrate the generation and detection of such pulses. The experiments involve a relativistic electron beam (tunable from 25-50 MeV) with a bunch length of 10 ps containing 1-2 nC, and an ultra short pulse (50-200 fs), high peak power (>2 TW) 0.8 {mu}m Ti:Al{sub 2}O{sub 3} laser system. The electron beam, focused down to about a 50 {mu}m waist size intersects the focused laser beam at 90{sup o}. The laser field acts as an electromagnetic undulator with strength K (quiver velocity of an electron normalized to the speed of light) for the relativistic electron beam, generating radiation up-shifted by 2{gamma}{sup 2}/(1+K{sup 2}/2) and a pulse length given by the overlapped interaction length in time of the laser beam and the electron beam. Here {gamma} is the usual Lorentz factor. Wavelength tuning will be accomplished in the experiment by generating wiggler strengths on the order of one as well as by electron beam energy tuning. For a 50 MeV electron beam and a laser beam focused to an intensity on the order of 10{sup 16} W/cm{sup 2}, the authors expect 10{sup 5} photons at 0.4 {angstrom} (10% bandwidth) in a cone angle of 6 mrad in a 170 fs pulse.

  15. Transparent Conductors from Carbon Nanotubes LBL-Assembled with Polymer Dopant with π-π Electron Transfer

    PubMed Central

    Zhu, Jian; Shim, Bong Sup; Di Prima, Matthew; Kotov, Nicholas A.

    2011-01-01

    Single-walled carbon nanotube (SWNT) and other carbon-based coatings are being considered as replacements for indium tin oxide (ITO). The problems of transparent conductors (TCs) coatings from SWNT and similar materials include poor mechanical properties, high roughness, low temperature resilience, and fast loss of conductivity. The simultaneous realization of these desirable characteristics can be achieved using high structural control of layer-by-layer (LBL) deposition, which is demonstrated by the assembly of hydroethyl cellulose (HOCS) and sulfonated polyetheretherketone (SPEEK)-SWNTs. A new type of SWNT doping based on electron transfer from valence bands of nanotubes to unoccupied levels of SPEEK through π-π interactions was identified for this system. It leads to a conductivity of 1.1×105 S/m at 66wt% loadings of SWNT. This is better than other polymer/SWNT composites and translates into surface conductivity of 920 ohms/sq and transmittance of 86.7% at 550nm. The prepared LBL films also revealed unusually high temperature resilience up to 500°C, and low roughness of 3.5 nm (ITO glass - 2.4 nm). Tensile modulus, ultimate strength, and toughness of such coatings are 13±2 GPa, 366±35 MPa and 8±3 kJ/m3, respectively, and exceed corresponding parameters of all similar TCs. The cumulative figure of merit, ΠTC, which included the critical failure strain relevant for flexible electronics, was ΠTC = 0.022 and should be compared to ΠTC = 0.006 for commercial ITO. Further optimization is possible using stratified nanoscale coatings and improved doping from the macromolecular LBL components. PMID:21524068

  16. Improving the connection between wood and cement using LBL nanocoating to create a lightweight, eco-friendly structural material

    NASA Astrophysics Data System (ADS)

    Bejo, L.; Major, B.; Csoka, L.; Hantos, Z.; Karacsonyi, Zs

    2016-04-01

    Structural elements made out of cement bonded wood may be an excellent alternative to flammable organic bonded composite beams, and CO2 intensive, heavy and nonrenewable reinforced concrete. Unfortunately, preliminary studies showed that a sufficient load-bearing performance is difficult to achieve. Improving the compatibility of cement and wood by LbL nanocoating may be a significant step towards creating viable cement bonded wood load bearing elements. The study involved creating multi layer nanocoating on the surface of poplar veneer using various polyelectrolyte combinations and numbers of treatment cycles, and testing the withdrawal resistance of the samples from a cement matrix. PDDA-PSS treatment was found to form increasingly uniform coating on the surface of wood, while the results were less straightforward for PAH-PSS. Both types and all levels of treatment caused dramatic improvement in load withdrawal resistance. The best result - a more than tenfold improvement - was achieved by at least 10 cycles of PDDA-PSS treatment. PAH-PSS treatment yielded a somewhat more modest improvement, which was already evident after five treatment cycles. The results point to the excellent potential of LbL nanocoating for creating cement bonded structural wood based composite materials.

  17. A study on the interactions of cationic porphyrin with nano clay platelets in Layer-by-Layer (LbL) self assembled films

    NASA Astrophysics Data System (ADS)

    Bhattacharjee, J.; Banik, Soma; Hussain, S. A.; Bhattacharjee, D.

    2015-07-01

    In the present communication, interaction of tetracationic porphyrin, 5,10,15,10-tetrakis (1-methyl-4-pyrindino) porphyrin tetra (p-toluenesulfonate) (TMPyP) with anionic nano clay platelets laponite has been studied in aqueous clay dispersion and Layer-by-Layer (LbL) self assembled film. Electrostatic adsorption of TMPyP molecules on clay platelets resulted in the flattenening of meso-substituent groups which led to the development of a new adsorbed band in the UV-vis absorption spectra. J-band was also formed due to overlapped organizations of organo-clay hybrid molecules in the LbL film leading to J-aggregates. Atomic force microscopic (AFM) studies gave visual evidence of this favoured organization in the monolayer LbL film.

  18. The use of TOUGH2 for the LBL/USGS 3-dimensional site-scale model of Yucca Mountain, Nevada

    SciTech Connect

    Bodvarsson, G.; Chen, G.; Haukwa, C.; Kwicklis, E.

    1995-12-31

    The three-dimensional site-scale numerical model o the unsaturated zone at Yucca Mountain is under continuous development and calibration through a collaborative effort between Lawrence Berkeley Laboratory (LBL) and the United States Geological Survey (USGS). The site-scale model covers an area of about 30 km{sup 2} and is bounded by major fault zones to the west (Solitario Canyon Fault), east (Bow Ridge Fault) and perhaps to the north by an unconfirmed fault (Yucca Wash Fault). The model consists of about 5,000 grid blocks (elements) with nearly 20,000 connections between them; the grid was designed to represent the most prevalent geological and hydro-geological features of the site including major faults, and layering and bedding of the hydro-geological units. Submodels are used to investigate specific hypotheses and their importance before incorporation into the three-dimensional site-scale model. The primary objectives of the three-dimensional site-scale model are to: (1) quantify moisture, gas and heat flows in the ambient conditions at Yucca Mountain, (2) help in guiding the site-characterization effort (primarily by USGS) in terms of additional data needs and to identify regions of the mountain where sufficient data have been collected, and (3) provide a reliable model of Yucca Mountain that is validated by repeated predictions of conditions in new boreboles and the ESF and has therefore the confidence of the public and scientific community. The computer code TOUGH2 developed by K. Pruess at LBL was used along with the three-dimensional site-scale model to generate these results. In this paper, we also describe the three-dimensional site-scale model emphasizing the numerical grid development, and then show some results in terms of moisture, gas and heat flow.

  19. Arming embolic beads with anti-VEGF antibodies and controlling their release using LbL technology.

    PubMed

    Sakr, O S; Berndt, S; Carpentier, G; Cuendet, M; Jordan, O; Borchard, G

    2016-02-28

    Transarterial chemoembolization (TACE) is used to treat various types of hypervascular tumors such as hepatocellular carcinoma and renal cancer. However, embolization and blocking of blood vessels nourishing a tumor mass evokes an angiogenic response due to the secretion of vascular endothelial growth factor (VEGF), which results in the formation of new blood vessels and eventually limitation in therapeutic efficacy. The presented work investigates the feasibility of loading the clinically used embolic beads (DC Bead®) with Bevacizumab (BEV), an anti-VEGF antibody, and control its release kinetics via Layer-by-Layer (LbL) coating. This strategy has the aim to achieve high, localized and sustained concentrations of BEV at the tumor site and reduce drug exposure in the systemic circulation. High loading of BEV on lyophilized beads of about 76mg BEV/bead vial was achieved. LbL coating was carried out by depositing alternating layers of the biocompatible polymers alginate and poly-L-lysine. Coating was proven successful by monitoring the reversal of zeta potential after addition of each layer. Morphological changes of the bead surface before and after coating were illustrated using SEM imaging. Moreover, release profiles from different formulations were studied and results showed that optimizing the number of deposited layers effectively slows the release of BEV for three days. Activity of released BEV was studied in different 2D and 3D cell based assays. Released BEV fractions showed comparable activity to fresh BEV solution used as control after 3days. In conclusion, our results suggest the opportunity for loading anti-VEGF antibodies on commercially available embolic beads to increase the efficacy of TACE of hypervascular tumors. PMID:26780173

  20. Surface immobilization of a tetra-ruthenium substituted polyoxometalate water oxidation catalyst through the employment of conducting polypyrrole and the layer-by-layer (LBL) technique.

    PubMed

    Anwar, Nargis; Sartorel, Andrea; Yaqub, Mustansara; Wearen, Kevin; Laffir, Fathima; Armstrong, Gordon; Dickinson, Calum; Bonchio, Marcella; McCormac, Timothy

    2014-06-11

    A tetra Ru-substituted polyoxometalate Na10[{Ru4O4(OH)2(H2O)4}(γ-SiW10O36)2] (Ru4POM) has been successfully immobilised onto glassy carbon electrodes and indium tin oxide (ITO) coated glass slides through the employment of a conducting polypyrrole matrix and the layer-by-layer (LBL) technique. The resulting Ru4POM doped polypyrrole films showed stable redox behavior associated with the Ru centres within the Ru4POM, whereas, the POM's tungsten-oxo redox centres were not accessible. The films showed pH dependent redox behavior within the pH range 2-5 whilst exhibiting excellent stability towards redox cycling. The layer-by-layer assembly was constructed onto poly(diallyldimethylammonium chloride) (PDDA) modified carbon electrodes by alternate depositions of Ru4POM and a Ru(II) metallodendrimer. The resulting Ru4POM assemblies showed stable redox behavior for the redox processes associated with Ru4POM in the pH range 2-5. The charge transfer resistance of the LBL films was calculated through AC-Impedance. Surface characterization of both the polymer and LBL Ru4POM films was carried out using atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Initial investigations into the ability of the Ru4POM LBL films to electrocatalytically oxidise water at pH 7 have also been conducted. PMID:24758586

  1. Proceedings of the 10th international workshop on ECR ion sources

    SciTech Connect

    Meyer, F W; Kirkpatrick, M I

    1991-01-01

    This report contains papers on the following topics: Recent Developments and Future Projects on ECR Ion Sources; Operation of the New KVI ECR Ion Source at 10 GHz; Operational Experience and Status of the INS SF-ECR Ion Source; Results of the New ECR4'' 14.5 GHz ECRIS; Preliminary Performance of the AECR; Experimental Study of the Parallel and Perpendicular Particle Losses from an ECRIS Plasma; Plasma Instability in Electron Cyclotron Resonance Heated Ion Sources; The Hyperbolic Energy Analyzer; Status of ECR Source Development; The New 10 GHz CAPRICE Source; First Operation of the Texas A M ECR Ion Source; Recent Developments of the RIKEN ECR Ion Sources; The 14 GHz CAPRICE Source; Characteristics and Potential Applications of an ORNL Microwave ECR Multicusp Plasma Ion Source; ECRIPAC: The Production and Acceleration of Multiply Charged Ions Using an ECR Plasma; ECR Source for the HHIRF Tandem Accelerator; Feasibility Studies for an ECR-Generated Plasma Stripper; Production of Ion Beams by using the ECR Plasmas Cathode; A Single Stage ECR Source for Efficient Production of Radioactive Ion Beams; The Single Staged ECR Source at the TRIUMF Isotope Separator TISOL; The Continuous Wave, Optically Pumped H{sup {minus}} Source; The H{sup +} ECR Source for the LAMPF Optically Pumped Polarized Ion Source; Present Status of the Warsaw CUSP ECR Ion Source; An ECR Source for Negative Ion Production; GYRAC-D: A Device for a 200 keV ECR Plasma Production and Accumulation; Status Report of the 14.4 GHZ ECR in Legnaro; Status of JYFL-ECRIS; Report on the Uppsala ECRIS Facility and Its Planned Use for Atomic Physics; A 10 GHz ECR Ion Source for Ion-Electron and Ion-Atom Collision Studies; and Status of the ORNL ECR Source Facility for Multicharged Ion Collision Research.

  2. SciDAC - The Scientific Data Management Center (http://sdmcenter.lbl.gov)

    SciTech Connect

    Ling Liu Calton Pu

    2005-06-20

    In SciDAC SDM project, the main assignment to the Georgia Institute of Technology team (according to the proposed work) is to develop advanced information extraction and information integration technologies on top of the XWRAP technology originated from Georgia Tech [LPH01]. We have developed XWRAPComposer technology to enable the XWRAP code generator to generate Java information wrappers that are capable of extraction of data from multiple linked pages. These information wrappers are used as gateways or adaptors for scientific information mediators to access and fuse interesting data and answering complex queries over a large collection of heterogeneous scientific information sources. Our accomplishments over the SciDAC sponsored years (July 2001 to July 2004) can be summarized along two dimensions. Technically, we have produced a number of major software releases and published over 30 research papers in both international conferences and international journals. The planned software releases include 1. Five Java wrappers and five WDSL-enabled wrappers for SDM Pilot scenarios, which were released in early 2003, 2. The XWRAPComposer toolkit (command line version) which was first released in late 2003 and then released in Summer 2004, 3. Five Ptolemy wrapper actors which were released first in Summer 2003, and then released again in Fall 2005. 4. The decomposable XWRAPComposer actor in Ptolemy, which we have made it available as open source in end of 2004 and tested it in early 2005.

  3. A der(11)t(4;11)(q21;p15) in a T-ALL/LBL patient.

    PubMed

    Colli, Sandra; Furforo, Lilian; Rojo Pisarello, Eduardo; Maidana, Marcela; Martín, Carlos; Bordone, Javier; Slavutsky, Irma

    2016-04-01

    Translocation t(4;11)(q21;p15) is a rare recurrent change associated to T-cell acute leukemia. In most cases, this alteration appears as the only abnormality or as part of a simple karyotype. In this report, we present the first case of T acute lymphoblastic leukemia/lymphoma (T-ALL/LBL) with the unbalanced translocation der(11)t(4;11)(q21;p15) as part of a very complex karyotype with multiple chromosome abnormalities, most of them not previously described in the literature. FISH (fluorescence in situ hybridization) and spectral karyotype (HiSKY) analysis confirmed the presence of complex alterations. The patient, a 16-year-old male, showed poor response to treatment and short survival (11 months). A detailed review of previously reported cases with t(4;11)(q21;p15) is also provided. The description of this type of alterations may contribute to the identification of new molecular mechanism associated to neoplastic development. PMID:26883452

  4. Preliminary development of the LBL/USGS three-dimensional site-scale model of Yucca Mountain, Nevada

    SciTech Connect

    Wittwer, C.; Chen, G.; Bodvarsson, G.S.; Chornack, M.; Flint, A.; Flint, L.; Kwicklis, E.; Spengler, R.

    1995-06-01

    A 3-D model of moisture flow within the unsaturated zone at Yucca Mountain is being developed at LBL in cooperation with USGS. This site-scale model covers an area of about 34 km{sup 2} and is bounded by major faults to the north, east, and west. The relatively coarse-grid model includes about 300 horizontal grid-blocks and 17 layers. Contour maps and isopach maps are presented defining different types of infiltration zones, and the spatial distribution of Tiva Canyon, Paintbrush, and Topopah Spring hydrogeological units. Matrix flow is approximated using the van Genuchten model, and the equivalent continuum approximation is used to account for fracture flow in the welded units. One-, two-, and three-dimensional simulations are conducted using the TOUGH2 computer program. Steady-state simulations are performed with various uniform and nonuniform infiltration rates; results are interpreted in terms of effect of fault characteristics on moisture flow distribution, and on the location and formation of preferential pathways.

  5. Effect of Layer-by-Layer (LbL) Encapsulation of Nano-Emulsified Fish Oil on Their Digestibility Ex Vivo and Skin Permeability In Vitro

    PubMed Central

    Jung, Eun Young; Hong, Ki Bae; Son, Heung Soo; Suh, Hyung Joo; Park, Yooheon

    2016-01-01

    Omega-3 rich fish oils are extremely labile, thus requiring control of oxidation and off flavor development. A recently proposed emulsification method, layer-by-layer (LbL) deposition, was found to be a plausible method to enhance the characteristics of bioactive ingredients, especially lipids. The present work was designed to test the possibility of enhancing the uptake and utilization of omega-3 fatty acids present in fish oil. The bioavailability of nano-emulsified fish oil was monitored in terms of intestinal absorption as well as skin permeability by using the everted intestinal sac model and Franz cell model. The skin permeability and intestinal absorption characteristics was significantly improved by LbL emulsification with lecithin/chitosan/low methoxypectin. Multilayer encapsulation along with nano-emulsification can be a useful method to deliver biologically active lipids and related components, such as fish oil. The protective effect of this tool from lipid oxidation still needs to be verified. PMID:27390723

  6. Development of ion beams for space effects testing using an ECR ion source

    SciTech Connect

    Benitez, Janilee; Hodgkinson, Adrian; Johnson, Mike; Loew, Tim; Lyneis, Claude; Phair, Larry

    2013-04-19

    At LBNL's 88-Inch Cyclotron and Berkeley Accelerator Space Effects (BASE) Facility, a range of ion beams at energies from 1 to 55 MeV/nucleon are used for radiation space effects testing. By bombarding a component with ion beams the radiation component of the space environment can be simulated and single event effects (SEEs) determined. The performance of electronic components used in space flight and high altitude aircraft can then be evaluated. The 88- Inch Cyclotron is coupled to the three electron cyclotron resonance ion sources (ECR, AECR-U, VENUS). These ion sources provide a variety of ion species, ranging from protons to heavy ions such as bismuth, for these tests. In particular the ion sources have been developed to provide {sup c}ocktails{sup ,} a mixture of ions of similar mass-to-charge ratio, which can be simultaneously injected into the cyclotron, but selectively extracted from it. The ions differ in both their linear energy transfer (LET) deposited to the part and in their penetration depth into the tested part. The current heavy ion cocktails available are the 4.5, 10, 16, and 30 MeV per nucleon.

  7. Development of ion beams for space effects testing using an ECR ion source

    NASA Astrophysics Data System (ADS)

    Benitez, Janilee; Hodgkinson, Adrian; Johnson, Mike; Loew, Tim; Lyneis, Claude; Phair, Larry

    2013-04-01

    At LBNL's 88-Inch Cyclotron and Berkeley Accelerator Space Effects (BASE) Facility, a range of ion beams at energies from 1 to 55 MeV/nucleon are used for radiation space effects testing. By bombarding a component with ion beams the radiation component of the space environment can be simulated and single event effects (SEEs) determined. The performance of electronic components used in space flight and high altitude aircraft can then be evaluated. The 88- Inch Cyclotron is coupled to the three electron cyclotron resonance ion sources (ECR, AECR-U, VENUS). These ion sources provide a variety of ion species, ranging from protons to heavy ions such as bismuth, for these tests. In particular the ion sources have been developed to provide "cocktails", a mixture of ions of similar mass-to-charge ratio, which can be simultaneously injected into the cyclotron, but selectively extracted from it. The ions differ in both their linear energy transfer (LET) deposited to the part and in their penetration depth into the tested part. The current heavy ion cocktails available are the 4.5, 10, 16, and 30 MeV per nucleon.

  8. Heparin-mimicking multilayer coating on polymeric membrane via LbL assembly of cyclodextrin-based supramolecules.

    PubMed

    Deng, Jie; Liu, Xinyue; Ma, Lang; Cheng, Chong; Shi, Wenbin; Nie, Chuanxiong; Zhao, Changsheng

    2014-12-10

    In this study, multifunctional and heparin-mimicking star-shaped supramolecules-deposited 3D porous multilayer films with improved biocompatibility were fabricated via a layer-by-layer (LbL) self-assembly method on polymeric membrane substrates. Star-shaped heparin-mimicking polyanions (including poly(styrenesulfonate-co-sodium acrylate; Star-PSS-AANa) and poly(styrenesulfonate-co-poly(ethylene glycol)methyl ether methacrylate; Star-PSS-EGMA)) and polycations (poly(methyl chloride-quaternized 2-(dimethylamino)ethyl methacrylate; Star-PMeDMA) were first synthesized by atom transfer radical polymerization (ATRP) from β-cyclodextrin (β-CD) based cores. Then assembly of 3D porous multilayers onto polymeric membrane surfaces was carried out by alternating deposition of the polyanions and polycations via electrostatic interaction. The surface morphology and composition, water contact angle, blood activation, and thrombotic potential as well as cell viability for the coated heparin-mimicking films were systematically investigated. The results of surface ATR-FTIR spectra and XPS spectra verified successful deposition of the star-shaped supramolecules onto the biomedical membrane surfaces; scanning electron microscopy (SEM) and atomic force microscopy (AFM) observations revealed that the modified substrate had 3D porous surface morphology, which might have a great biological influence on the biointerface. Furthermore, systematic in vitro investigation of protein adsorption, platelet adhesion, human platelet factor 4 (PF4, indicates platelet activation), activate partial thromboplastin time (APTT), thrombin time (TT), coagulation activation (thrombin-antithrombin III complex (TAT, indicates blood coagulant)), and blood-related complement activation (C3a and C5a, indicates inflammation potential) confirmed that the heparin-mimicking multilayer coated membranes exhibited ultralow blood component activations and excellent hemocompatibility. Meanwhile, after surface coating

  9. A new 14 GHz Electron-Cyclotron-Resonance Ion Source (ECRIS) for the heavy ion accelerator facility ATLAS

    SciTech Connect

    Schlapp, M.; Pardo, R.C.; Vondrasek, R.C.; Billquist, P.J.; Szczech, J.

    1997-11-01

    A 14 GHz Electron-Cyclotron-Resonance Ion Source (ECRIS) has been designed and built at Argonne National Laboratory. The source is a modification of the AECR at Berkeley and incorporates the latest results from ECR developments to produce intense beams of highly charged ions, including an improved magnetic confinement of the plasma electrons with an axial mirror ratio of 3.5. The aluminum plasma chamber and extraction electrode as well as a biased disk on axis at the microwave injection side donates additional electrons to the plasma, making use of the large secondary electron yield from aluminum oxide. The source is capable of ECR plasma heating using two different frequencies simultaneously to increase the electron energy gain for the production of high charge states. The main design goal is to produce several e{mu}A of at least {sup 238}U{sup 35+} in order to accelerate the beam to coulomb-barrier energies without further stripping. First charge state distributions for gaseous elements have been measured and 210 e{mu}A {sup 16}O{sup 7+} has been achieved. A normalized 90% emittance from 0.1 to 0.2 {pi} mm{sm_bullet}mrad for krypton and oxygen beam has been found.

  10. Thermal and structural analysis of the LBL 10 x 40 cm long pulse accelerator and the 12 x 48 cm common long pulse accelerator for TFTR, doublet III-D, and MFTF-B

    SciTech Connect

    Wells, R.P.

    1985-11-01

    Stress and deflection of the grid rails of the existing, Lawrence Berkeley Laboratory (LBL) designed, 10 x 40 cm Long Pulse (neutral beam) Accelerator (40LPA) and the expanded 12 x 48 cm version, Common Long Pulse Source (CLPS), have been computed for a series of assumed heat load distributions. The combined stress from self-constraint of thermal expansion and rail holder reaction forces has been calculated. A simplification of the gradient grid rail holder was analyzed and was found to work as well or better than the original 40LPA design under the most probable operating conditions. Heat flux non-uniformity over the rail surface for both accelerator designs was estimated from 40LPA grid calorimetry data for arc and beam extraction operation. The extrapolated total heat load per rail for the CLPS was less than the 1.2 kW value used in this analysis. Under worst case assumptions, the maximum equivalent stress in any of the molybdenum grid rails was less than 20% of yield. For the anticipated heat load distribution on the gradient grid, the predicted deflection of the grid rail meets the 0.0457 mm position tolerance except under extremely non-uniform heat loads.

  11. Effects of total pressure on non-grey gas radiation transfer in oxy-fuel combustion using the LBL, SNB, SNBCK, WSGG, and FSCK methods

    NASA Astrophysics Data System (ADS)

    Chu, Huaqiang; Gu, Mingyan; Consalvi, Jean-Louis; Liu, Fengshan; Zhou, Huaichun

    2016-03-01

    The effects of total pressure on gas radiation heat transfer are investigated in 1D parallel plate geometry containing isothermal and homogeneous media and an inhomogeneous and non-isothermal CO2-H2O mixture under conditions relevant to oxy-fuel combustion using the line-by-line (LBL), statistical narrow-band (SNB), statistical narrow-band correlated-k (SNBCK), weighted-sum-of-grey-gases (WSGG), and full-spectrum correlated-k (FSCK) models. The LBL calculations were conducted using the HITEMP2010 and CDSD-1000 databases and the LBL results serve as the benchmark solution to evaluate the accuracy of the other models. Calculations of the SNB, SNBCK, and FSCK were conducted using both the 1997 EM2C SNB parameters and their recently updated 2012 parameters to investigate how the SNB model parameters affect the results under oxy-fuel combustion conditions at high pressures. The WSGG model considered is the recently developed one by Bordbar et al. [19] for oxy-fuel combustion based on LBL calculations using HITEMP2010. The total pressure considered ranges from 1 up to 30 atm. The total pressure significantly affects gas radiation transfer primarily through the increase in molecule number density and only slightly through spectral line broadening. Using the 1997 EM2C SNB model parameters the accuracy of SNB and SNBCK is very good and remains essentially independent of the total pressure. When using the 2012 EM2C SNB model parameters the SNB and SNBCK results are less accurate and their error increases with increasing the total pressure. The WSGG model has the lowest accuracy and the best computational efficiency among the models investigated. The errors of both WSGG and FSCK using the 2012 EM2C SNB model parameters increase when the total pressure is increased from 1 to 10 atm, but remain nearly independent of the total pressure beyond 10 atm. When using the 1997 EM2C SNB model parameters the accuracy of FSCK only slightly decreases with increasing the total pressure.

  12. Characterization and nanoindentation testing of thin ZrO 2 films synthesized using layer-by-layer (LbL) deposited organic templates

    NASA Astrophysics Data System (ADS)

    Zlotnikov, I.; Gotman, I.; Gutmanas, E. Y.

    2008-12-01

    Thin organic LbL (layer-by-layer) films with negatively charged surface were used as templates for biomimetic deposition of ZrO 2 on Si wafers by hydrolysis of Zr(SO 4) 2 solution. The as-deposited ceramic layers were fully amorphous and were composed of the mixture of zirconia and zirconium sulfate. During transmission electron microscopy (TEM) examination, the amorphous ZrO 2 crystallized almost instantaneously to tetragonal (t) ZrO 2 under the electron beam. The ≤110 nm thick as-deposited layers were crack-free and adhered well to the LbL surface. Annealing at 500 °C led to complete crystallization of amorphous ZrO 2 to nanocrystalline t-ZrO 2. Further heating to 900 °C resulted in transformation to monoclinic ZrO 2, complete removal of sulfur and twofold shrinkage of the ceramic layer thickness. Both the nanohardness and elastic modulus of the deposited zirconia layers were significantly improved following the heat treatments.

  13. LbL Assembly of Albumin on Nitric Oxide-Releasing Silica Nanoparticles Using Suramin, a Polyanion Drug, as an Interlayer Linker.

    PubMed

    Chou, Hung-Chang; Chiu, Shih-Jiuan; Hu, Teh-Min

    2015-08-10

    Preformed protein corona of nanoparticles can be utilized as a promising formulation strategy for improving nano drug delivery. Nitric oxide (NO) is a labile molecule with extensive therapeutic implications. In this study, we test whether preformation of protein coatings can enhance the performance of NO-delivering nanoparticles. S-Nitroso (SNO) silica nanoparticles (SNO-SiNPs) were prepared using a nanoprecipitation method. For the first time, bovine serum albumin (BSA) was used to coat NO-releasing nanoparticles, facilitated by a polyanionic drug, suramin, under a layer-by-layer (LbL) scheme. Bare and coated nanoparticles were characterized by zeta-potential, size, and spectroscopic measurements. We demonstrate that albumin/suramin-surface coassembly has advantages in preventing particle aggregation during lyophilization, controlling NO release and exerting an enhanced anticancer effect. PMID:26121207

  14. An improved layer-by-layer self-assembly technique to generate biointerfaces for platelet adhesion studies: Dynamic LbL

    NASA Astrophysics Data System (ADS)

    Lopez, Juan Manuel

    Layer-by-layer self-assembly (LbL) is a technique that generates engineered nano-scale films, coatings, and particles. These nanoscale films have recently been used in multiple biomedical applications. Concurrently, microfabrication methods and advances in microfluidics are being developed and combined to create "Lab-on-a-Chip" technologies. The potential to perform complex biological assays in vitro as a first-line screening technique before moving on to animal models has made the concept of lab on a chip a valuable research tool. Prior studies in the Biofluids Laboratory at Louisiana Tech have used layer-by-layer and in vitro biological assays to study thrombogenesis in a controlled, repeatable, engineered environment. The reliability of these previously established techniques was unsatisfactory for more complex cases such as chemical and shear stress interactions. The work presented in this dissertation was performed to test the principal assumptions behind the established laboratory methodologies, suggest improvements where needed, and test the impact of these improvements on accuracy and repeatability. The assumptions to be tested were: (1) The fluorescence microscopy (FM) images of acridine orange-tagged platelets accurately provide a measure of percent area of surface covered by platelets; (2) fibrinogen coatings can be accurately controlled, interact with platelets, and do not interfere with the ability to quantify platelet adhesion; and (3) the dependence of platelet adhesion on chemical agents, as measured with the modified methods, generally agrees with results obtained from our previous methods and with known responses of platelets that have been documented in the literature. The distribution of fibrinogen on the final LbL surface generated with the standard, static process (s-LbL) was imaged by tagging the fibrinogen with an anti-fibrinogen antibody bound to fluorescein isothiocyanate (FITC). FITC FM images and acridine orange FM images were taken

  15. LBL's Pollution Instrumentation Comparability Program.

    ERIC Educational Resources Information Center

    McLaughlin, R. D.; And Others

    1979-01-01

    Contained are condensed excerpts from the Lawrence Berkeley Laboratory Survey of Instrumentation for Environmental Monitoring. The survey describes instrumentation used to analyze air and water quality, radiation emissions, and biomedical impacts. (BB)

  16. XUV synchrotron optical components for the Advanced Light Source: Summary of the requirements and the developmental program

    SciTech Connect

    McKinney, W.; Irick, S.; Lunt, D.

    1992-07-01

    We give a brief summary of the requirements for water cooled optical components for the Advanced Light Source (ALS), a third generation synchrotron radiation source under construction at Lawrence Berkeley Laboratory (LBL). Materials choices, surface figure and smoothness specifications, and metrology systems for measuring the plated metal surfaces are discussed. Results from a finished water cooled copper alloy mirror will be used to demonstrate the state of the art in optical metrology with the Takacs Long Trace Profiler (LTP II).

  17. Electronic systems for transverse coupled-bunch feedback in the Advanced Light Source (ALS)

    SciTech Connect

    Barry, W.; Lambertson, G.R.; Lo, C.C.

    1993-10-01

    In order to effectively control a large number of transverse coupled-bunch modes in the LBL Advanced Light Source (ALS) storage ring, a broad-band, bunch-by-bunch feedback system has been designed, and is beginning to undergo testing and commissioning. This paper addresses, in some detail, the major electronic components of the feedback system. In particular, the components described include: broad-band microwave position detection receivers, closed orbit offset signal rejection circuitry, and baseband quadrature processing circuitry.

  18. A 6.3 T Bend Magnet for the Advanced Light Source

    SciTech Connect

    Taylor, C.E.; Caspi, S.

    1995-06-07

    The Advanced Light Source (ALS) is a 1.5 to 1.9 GeV high-brightness electron storage ring operating at Lawrence Berkeley Laboratory (LBL) that provides synchrotron radiation for a large variety of users. It Is proposed to replace three of the thirty six 1.5T, one meter long bend magnets with very sbort high-field superconductlng (SC) dipoles. These magnets would provide bend-magnet synchrotron radiation to six bcamlines with a critical energy of at least 6 keV that is much better suited for protein crystallography and other small-sample x-ray diffraction and adsorption studies, than is currently available at the ALS. The magnet design is described, including coil, yoke, magnetic field analysis, and cyrostat. A prototype magnet is under construction at LBL.

  19. Performance of the Advanced Light Source

    SciTech Connect

    Jackson, A.

    1994-06-01

    The Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory (LBL) is the first of the lower energy (1--2 GeV) third-generation synchrotron radiation facilities to come into operation. Designed with very small electron beam emittances to operate with long insertion devices producing very high brightness beams of synchrotron radiation in the VUV and soft x-ray regions of the spectrum, these facilities are complementary to the higher energy (6--9 GeV) facilities designed for harder x-radiation. The ALS storage ring began operation in October 1993. In this paper, we will review the operational performance of the ALS, including the effects of the 4.5 m long undulators (period 5 cm), and discuss the overall performance of the facility.

  20. Advanced Light Source beam position monitor

    SciTech Connect

    Hinkson, J.

    1991-10-28

    The Advanced Light Source (ALS) is a synchrotron radiation facility nearing completion at LBL. As a third-generation machine, the ALS is designed to produce intense light from bend magnets, wigglers, and undulators (insertion devices). The facility will include a 50 MeV electron linear accelerator, a 1.5 GeV booster synchrotron, beam transport lines, a 1--2 GeV storage ring, insertion devices, and photon beam lines. Currently, the beam injection systems are being commissioned, and the storage ring is being installed. Electron beam position monitors (BPM) are installed throughout the accelerator and constitute the major part of accelerator beam diagnostics. The design of the BPM instruments is complete, and 50 units have been constructed for use in the injector systems. We are currently fabricating 100 additional instruments for the storage ring. In this paper I discuss engineering fabrication, testing and performance of the beam pickup electrodes and the BPM electronics.

  1. Parameter studies of candidate lattices for the 1-2 GeV synchrotron radiation source

    SciTech Connect

    Zisman, M.S.

    1986-01-13

    This document discusses the implications of various collective phenomena on the required performance of candidate lattices for the LBL 1 to 2 GeV Synchrotron Radiation Source. The performance issues considered include bunch length, emittance growth, and beam lifetime. In addition, the possible use of the 1 to 2 GeV Synchrotron Radiation Source as a high-gain FEL is explored briefly. Generally, the differences between lattices are minor. It appears that the most significant feature distinguishing the various alternatives will be the beam lifetime.

  2. ECR (Electron Cyclotron Resonance) ion sources for cyclotrons

    SciTech Connect

    Lyneis, C.M.

    1986-10-01

    In the last decade ECR (Electron Cyclotron Resonance) ion sources have evolved from a single large, power consuming, complex prototype into a variety of compact, simple, reliable, efficient, high performance sources of high charge state ions for accelerators and atomic physics. The coupling of ECR sources to cyclotrons has resulted in significant performance gains in energy, intensity, reliability, and variety of ion species. Seven ECR sources are in regular operation with cyclotrons and numerous other projects are under development or in the planning stag. At least four laboratories have ECR sources dedicated for atomic physics research and other atomic physics programs share ECR sources with cyclotrons. An ECR source is now installed on the injector for the CERN SPS synchrotron to accelerate O/sup 8 +/ to relativistic energies. A project is underway at Argonne to couple an ECR source to a superconducting heavy-ion linac. Although tremendous progress has been made, the field of ECR sources is still a relatively young technology and there is still the potential for further advances both in source development and understanding of the plasma physics. The development of ECR sources is reviewed. The important physics mechanisms which come into play in the operation of ECR Sources are discussed, along with various models for charge state distributions (CSD). The design and performance of several ECR sources are compared. The 88-Inch Cyclotron and the LBL ECR is used as an example of cyclotron+ECR operation. The future of ECR sources is considered.

  3. Measurements of neutral beam species, impurities, spatial divergence, energy dispersion, pressure, and reionization for the TFTR (Tokamak Fusion Test Reactor) US Common Long Pulse Ion Source

    SciTech Connect

    Kugel, H.W.; Gammel, G.M.; Grisham, L.R.; Kaita, R.; Kamperschroer, J.H.; Langley, R.A.; Magee, C.W.; Medley, S.S.; Murphy, T.J.; Roquemore, A.L.; Williams, M.D.

    1988-06-01

    Physical characteristics of TFTR neutral beams were measured during the first tests and initial operating experience with production TFTR US Common Long Pulse Ion Sources on beamlines in the TFTR experimental environment under actual user conditions. These measurements were performed with different power supply systems, controls, diagnostics, and operating methods compared to those used at LBL during the development phase. The set of diagnostics included water calorimetry, thermocouples, vacuum ionization gauges, photodiodes, neutron, gamma-ray and charged particle backscatter spectroscopy, and implantation/secondary ion mass spectroscopy. These systems were used to perform complementary measurements of neutral beam species, measurements were performed either in the neutralizer region, where the beam contained both ions and neutrals, or in the region of the output neutral beam. In general, consistent with estimates made during the LBL development phase. They can provide guidance for the optimization of TFTR neutral beam heating operations and the understanding of auxilliary heated TFTR plasmas. 21 refs., 28 figs., 2 tabs.

  4. ZAP and its application to the optimization of synchrotron light source parameters

    SciTech Connect

    Zisman, M.S.

    1987-03-01

    The design of electron storage rings for the production of synchrotron radiation has become increasingly sophisticated in recent years. To assist in the optimization of such storage rings, a new, user-friendly code to treat the relevant collective phenomena, called ZAP, has been written at LBL. The code is designed primarily to carry out parameter studies of electron storage rings, although options for protons or heavy ions are included where appropriate. In this paper, we first describe the contents of the code itself, and then illustrate, via selected examples, how the collective effects treated by ZAP manifest themselves in the new generation of synchrotron light sources.

  5. LBL resistivity studies at Cerro Prieto

    SciTech Connect

    Wilt, M.J.; Goldstein, N.E.; Razo, A.M.

    1980-01-01

    A series of dc resistivity studies were performed at the Cerro Prieto geothermal field. In the present study dipole-dipole resistivity data have been collected and two-dimensional modeling studies have been performed using these and existing Schlumberger data taken by the CFE. 10 refs.

  6. The LBL geothermal reservoir technology program

    SciTech Connect

    Lippmann, M.J.

    1991-03-01

    The main objective of the DOE/GD-funded Geothermal Reservoir Technology Program at Lawrence Berkeley Laboratory is the development and testing of new and improved methods and tools needed by industry in its effort to delineate, characterize, evaluate, and exploit hydrothermal systems for geothermal energy. This paper summarizes the recent and ongoing field, laboratory, and theoretical research activities being conducted as part of the Geothermal Reservoir Technology Program. 28 refs., 4 figs.

  7. COMBUSTION AREA SOURCES: DATA SOURCES

    EPA Science Inventory

    The report identifies, documents, and evaluates data sources for stationary area source emissions, including solid waste and agricultural burning. Area source emissions of particulate matter, sulfur dioxide, oxides of nitrogen, reactive volatile organic compounds, and carbon mon...

  8. COMBUSTION AREA SOURCES: DATA SOURCES

    EPA Science Inventory

    The report identifies, documents, and evaluates data sources for stationary area source emissions, including solid waste and agricultural burning. rea source emissions of particulate matter, sulfur dioxide, oxides of nitrogen, reactive volatile organic compounds, and carbon monox...

  9. Wigglers at the Advanced Light Source

    SciTech Connect

    Hoyer, E.; Akre, J.; Humphries, D.

    1995-04-01

    Two 3.4 m long wigglers are being designed and constructed at Lawrence Berkeley Laboratory`s (LBL) Advanced Light Source (ALS). A 19 period planar wiggler with 16.0 cm period length is designed to provide photons up to 12.4 keV for protein crystallography. This device features a hybrid permanent magnet structure with tapered poles and designed to achieve 2.0 T at a 1.4 cm magnetic gap. An elliptical wiggler is being designed to provide circularly polarized photons in the energy range of 50 eV to 10 keV for magnetic circular dichroism spectroscopy. This device features vertical and horizontal magnetic structures of 14 and 14 {1/2} periods respectively of 20 cm period length. The vertical magnetic structure is a 2.0 T hybrid permanent magnet configuration. The horizontal structure is an iron core electromagnetic design, shifted longitudinally {1/4} period with respect to the vertical magnetic structure. A maximum horizontal peak field of 0.1 T at an oscillating frequency up to 1 Hz will be achieved by excitation of the horizontal poles with a trapezoidal current waveform.

  10. First undulators for the Advanced Light Source

    SciTech Connect

    Hoyer, E.; Akre, J.; Chin, J.

    1993-05-01

    The first three undulators, each 4.6 m in length, for the Advanced Light source (ALS) at Lawrence Berkeley Laboratory (LBL), are near completion and are undergoing qualification tests before installation into the storage ring. Two devices have 5.0-cm period lengths, 89 periods, and achieve an effective field of 0.85 T at the 14 mm minimum magnetic gap. The other device has a period length of 8.0 cm, 55 periods, and an effective field of 1.2 T at the minimum 14 mm gap. Measurements on the first 5 cm period device show the uncorrelated field errors to be 0.23%, which is less than the required 0.25%. Measurements of gap control show reproducibility of {plus_minus}5 microns or better. The first vacuum chamber, 5.0 m long, is flat to within 0.53 mm over the 4.6 m magnetic structure section and a 4 x 10{sup -11} Torr pressure was achieved during vacuum tests. Device description, fabrication, and measurements are presented.

  11. A figure of merit for blazar-like source identification in the gamma-ray energy band

    SciTech Connect

    Cavazzuti, Elisabetta; Pittori, Carlotta; Giommi, Paolo; Colafrancesco, Sergio

    2007-07-12

    The microwave to gamma-ray slope {alpha}{mu}{gamma} can be used as a viable figure of merit for blazar-like source identification in gamma-rays. Taking into account the constraints from the observed extragalactic gamma-ray background, one can estimate the maximum duty cycle allowed for a selected sample of low energy peaked (LBL) blazars, in order to be detectable for the nominal sensitivity values of AGILE and GLAST gamma-ray experiments. This work is based on the results of a recently derived blazar radio LogN-LogS obtained by combining several multi-frequency surveys. We present our estimates of duty cycle constraints applied on a sample composed by 146 high latitude and 74 medium latitude LBL blazars from the new WMAP3 yr catalog. Our results can be used as an indicator to identify good gamma-ray blazar candidates: sources with high values of duty cycle can in principle be detectable also in a ''steady'' state by AGILE and GLAST without over-predicting the extragalactic background.

  12. Preliminary design report of a relativistic-Klystron two-beam-accelerator based power source for a 1 TeV center-of-mass next linear collider

    SciTech Connect

    Yu, S.; Goffeney, N.; Henestroza, E.

    1995-02-22

    A preliminary point design for an 11.4 GHz power source for a 1 TeV center-of-mass Next Linear Collider (NLC) based on the Relativistic-Klystron Two-Beam-Accelerator (RK-TBA) concept is presented. The present report is the result of a joint LBL-LLNL systems study. consisting of three major thrust areas: physics, engineering, and costing. The new RK-TBA point design, together with our findings in each of these areas, are reported.

  13. Selection Sources.

    ERIC Educational Resources Information Center

    Kerby, Ramona

    2002-01-01

    Discusses library collection development by school library media specialists and describes selection sources for new books and materials; retrospective selection sources for materials published in preceding years; and an acquisition source. Provides an overview of the selection process and includes 10 suggestions for selection. (LRW)

  14. Nonpoint Sources.

    ERIC Educational Resources Information Center

    Browne, F. X.

    1978-01-01

    Presented a literature review of nonpoint source effects on water quality and pollution covering: (1) water quality effects; (2) watershed studies; (3) nonpoint source models; and nonpoint source controls. A list of 122 references published in 1976 and 1977 is also presented. (HM)

  15. Nonpoint sources

    SciTech Connect

    Selzer, L.

    1994-12-31

    Nonpoint source pollution remains the most pervasive water quality issue faced today. Unlike pollution from point sources, nonpoint source pollution is diffuse both in terms of its origin and the manner in which it enters ground and surface waters. It results from a great variety of human activities that take place over a wide geographic area perhaps many hundreds or even thousands of acres. And unlike pollutants from point sources--which enter the environment at well-defined locations and in relatively even, continuous discharges--pollutants from nonpoint sources usually find their way into surface and ground waters in sudden surges associated with rainfall, thunderstorms, or snowmelt. The author discusses some of the most significant sources of nonpoint source pollution.

  16. Laser sources and techniques for spectroscopy and dynamics

    SciTech Connect

    Kung, A.H.

    1993-12-01

    This program focuses on the development of novel laser and spectroscopic techniques in the IR, UV, and VUV regions for studying combustion related molecular dynamics at the microscopic level. Laser spectroscopic techniques have proven to be extremely powerful in the investigation of molecular processes which require very high sensitivity and selectivity. The authors approach is to use quantum electronic and non-linear optical techniques to extend the spectral coverage and to enhance the optical power of ultrahigh resolution laser sources so as to obtain and analyze photoionization, fluorescence, and photoelectron spectra of jet-cooled free radicals and of reaction products resulting from unimolecular and bimolecular dissociations. New spectroscopic techniques are developed with these sources for the detection of optically thin and often short-lived species. Recent activities center on regenerative amplification of high resolution solid-state lasers, development of tunable high power mid-IR lasers and short-pulse UV/VUV tunable lasers, and development of a multipurpose high-order suppressor crossed molecular beam apparatus for use with synchrotron radiation sources. This program also provides scientific and technical support within the Chemical Sciences Division to the development of LBL`s Combustion Dynamics Initiative.

  17. Ion source

    DOEpatents

    Leung, Ka-Ngo; Ehlers, Kenneth W.

    1984-01-01

    A magnetic filter for an ion source reduces the production of undesired ion species and improves the ion beam quality. High-energy ionizing electrons are confined by the magnetic filter to an ion source region, where the high-energy electrons ionize gas molecules. One embodiment of the magnetic filter uses permanent magnets oriented to establish a magnetic field transverse to the direction of travel of ions from the ion source region to the ion extraction region. In another embodiment, low energy 16 eV electrons are injected into the ion source to dissociate gas molecules and undesired ion species into desired ion species.

  18. ION SOURCE

    DOEpatents

    Martina, E.F.

    1958-04-22

    An improved ion source particularly adapted to provide an intense beam of ions with minimum neutral molecule egress from the source is described. The ion source structure includes means for establishing an oscillating electron discharge, including an apertured cathode at one end of the discharge. The egress of ions from the source is in a pencil like beam. This desirable form of withdrawal of the ions from the plasma created by the discharge is achieved by shaping the field at the aperture of the cathode. A tubular insulator is extended into the plasma from the aperture and in cooperation with the electric fields at the cathode end of the discharge focuses the ions from the source,

  19. Light Source

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Research on food growth for long duration spacecraft has resulted in a light source for growing plants indoors known as Qbeam, a solid state light source consisting of a control unit and lamp. The light source, manufactured by Quantum Devices, Inc., is not very hot, although it generates high intensity radiation. When Ron Ignatius, an industrial partner of WCSAR, realized that terrestrial plant research lighting was not energy efficient enough for space use, he and WCSAR began to experiment with light emitting diodes. A line of LED products was developed, and QDI was formed to market the technology. An LED-based cancer treatment device is currently under development.

  20. NEUTRON SOURCES

    DOEpatents

    Richmond, J.L.; Wells, C.E.

    1963-01-15

    A neutron source is obtained without employing any separate beryllia receptacle, as was formerly required. The new method is safer and faster, and affords a source with both improved yield and symmetry of neutron emission. A Be container is used to hold and react with Pu. This container has a thin isolating layer that does not obstruct the desired Pu--Be reaction and obviates procedures previously employed to disassemble and remove a beryllia receptacle. (AEC)

  1. An RF driven H{sup {minus}} source and a low energy beam injection system for RFQ operation

    SciTech Connect

    Leung, K.N.; Bachman, D.A.; Chan, C.F.; McDonald, D.S.

    1992-12-31

    An RF driven H{sup {minus}} source has been developed at LBL for use in the Superconducting Super Collider (SSC). To date, an H{sup {minus}} current of {approx}40 mA can be obtained from a 5.6-cm-diam aperture with the source operated at a pressure of about 12 m Torr and 50 kW of RF power. In order to match the accelerated H{sup {minus}} beam into the SSC RFQ, a low-energy H{sup {minus}} injection system has been designed. This injector produces an outgoing H{sup {minus}} beam free of electron contamination, with small radius, large convergent angle and small projectional emittance.

  2. ION SOURCE

    DOEpatents

    Leland, W.T.

    1960-01-01

    The ion source described essentially eliminater the problem of deposits of nonconducting materials forming on parts of the ion source by certain corrosive gases. This problem is met by removing both filament and trap from the ion chamber, spacing them apart and outside the chamber end walls, placing a focusing cylinder about the filament tip to form a thin collimated electron stream, aligning the cylinder, slits in the walls, and trap so that the electron stream does not bombard any part in the source, and heating the trap, which is bombarded by electrons, to a temperature hotter than that in the ion chamber, so that the tendency to build up a deposit caused by electron bombardment is offset by the extra heating supplied only to the trap.

  3. Neutron source

    DOEpatents

    Cason, J.L. Jr.; Shaw, C.B.

    1975-10-21

    A neutron source which is particularly useful for neutron radiography consists of a vessel containing a moderating media of relatively low moderating ratio, a flux trap including a moderating media of relatively high moderating ratio at the center of the vessel, a shell of depleted uranium dioxide surrounding the moderating media of relatively high moderating ratio, a plurality of guide tubes each containing a movable source of neutrons surrounding the flux trap, a neutron shield surrounding one part of each guide tube, and at least one collimator extending from the flux trap to the exterior of the neutron source. The shell of depleted uranium dioxide has a window provided with depleted uranium dioxide shutters for each collimator. Reflectors are provided above and below the flux trap and on the guide tubes away from the flux trap.

  4. Crowd Sourcing.

    PubMed

    Baum, Neil

    2016-01-01

    The Internet has contributed new words and slang to our daily vernacular. A few terms, such as tweeting, texting, sexting, blogging, and googling, have become common in most vocabularies and in many languages, and are now included in the dictionary. A new buzzword making the rounds in industry is crowd sourcing, which involves outsourcing an activity, task, or problem by sending it to people or groups outside a business or a practice. Crowd sourcing allows doctors and practices to tap the wisdom of many instead of relying only on the few members of their close-knit group. This article defines "crowd sourcing," offers examples, and explains how to get started with this approach that can increase your ability to finish a task or solve problems that you don't have the time or expertise to accomplish. PMID:27039640

  5. NEUTRON SOURCE

    DOEpatents

    Reardon, W.A.; Lennox, D.H.; Nobles, R.G.

    1959-01-13

    A neutron source of the antimony--beryllium type is presented. The source is comprised of a solid mass of beryllium having a cylindrical recess extending therein and a cylinder containing antimony-124 slidably disposed within the cylindrical recess. The antimony cylinder is encased in aluminum. A berylliunn plug is removably inserted in the open end of the cylindrical recess to completely enclose the antimony cylinder in bsryllium. The plug and antimony cylinder are each provided with a stud on their upper ends to facilitate handling remotely.

  6. RADIATION SOURCES

    DOEpatents

    Brucer, M.H.

    1958-04-15

    A novel long-lived source of gamma radiation especially suitable for calibration purposes is described. The source of gamma radiation is denoted mock iodine131, which comprises a naixture of barium-133 and cesium-137. The barium and cesium are present in a barium-cesium ratio of approximately 5.7/1 to 14/1, uniformly dispersed in an ion exchange resin and a filter surrounding the resin comprised of a material of atomic number below approximately 51, and substantially 0.7 to 0.9 millimeter thick.

  7. Superluminal sources.

    PubMed Central

    Vermeulen, R C

    1995-01-01

    Predictions for the apparent velocity statistics under simple beaming models are presented and compared to the observations. The potential applications for tests of unification models and for cosmology (source counts, measurements of the Hubble constant H0 and the deceleration parameter q0) are discussed. First results from a large homogeneous survey are presented. The data do not show compelling evidence for the existence of intrinsically different populations of galaxies, BL Lacertae objects, or quasars. Apparent velocities betaapp in the range 1-5 h-1, where h = H0/100 km.s-1.Mpc-1 [1 megaparsec (Mpc) = 3.09 x 10(22) m], occur with roughly equal frequency; higher values, up to betaapp = 10 h-1, are rather more scarce than appeared to be the case from earlier work, which evidently concentrated on sources that are not representative of the general population. The betaapp distribution suggests that there might be a skewed distribution of Lorentz factors over the sample, with a peak at gammab approximately 2 h-1 and a tail up to at least gammab approximately 10 h-1. There appears to be a clearly rising upper envelope to the betaapp distribution when plotted as a function of observed 5-GHz luminosity; a combination of source counts and the apparent velocity statistics in a larger sample could provide much insight into the properties of radio jet sources. PMID:11607604

  8. Terahertz sources

    NASA Astrophysics Data System (ADS)

    Shumyatsky, Pavel; Alfano, Robert R.

    2011-03-01

    We present an overview and history of terahertz (THz) sources for readers of the biomedical and optical community for applications in physics, biology, chemistry, medicine, imaging, and spectroscopy. THz low-frequency vibrational modes are involved in many biological, chemical, and solid state physical processes.

  9. ION SOURCE

    DOEpatents

    Bell, W.A. Jr.; Love, L.O.; Prater, W.K.

    1958-01-28

    An ion source is presented capable of producing ions of elements which vaporize only at exceedingly high temperatures, i.e.,--1500 degrees to 3000 deg C. The ion source utilizes beams of electrons focused into a first chamber housing the material to be ionized to heat the material and thereby cause it to vaporize. An adjacent second chamber receives the vaporized material through an interconnecting passage, and ionization of the vaporized material occurs in this chamber. The ionization action is produced by an arc discharge sustained between a second clectron emitting filament and the walls of the chamber which are at different potentials. The resultant ionized material egresses from a passageway in the second chamber. Using this device, materials which in the past could not be processed in mass spectometers may be satisfactorily ionized for such applications.

  10. ION SOURCE

    DOEpatents

    Blue, C.W.; Luce, J.S.

    1960-07-19

    An ion source is described and comprises an arc discharge parallel to the direction of and inside of a magnetic field. an accelerating electrode surrounding substantially all of the discharge except for ion exit apertures, and means for establishing an electric field between that electrode and the arc discharge. the electric field being oriented at an acute angle to the magnetic field. Ions are drawn through the exit apertures in the accelrating electrcde in a direction substantially divergent to the direction of the magnetic field and so will travel in a spiral orbit along the magnetic field such that the ions will not strike the source at any point in their orbit within the magnetic field.

  11. Ion source

    DOEpatents

    Brobeck, W. M.

    1959-04-14

    This patent deals with calutrons and more particularly to an arrangement therein whereby charged bottles in a calutron source unit may be replaced without admitting atmospheric air to the calutron vacuum chamber. As described, an ion unit is disposed within a vacuum tank and has a reservoir open toward a wall of the tank. A spike projects from the source into the reservoir. When a charge bottle is placed in the reservoir, the spike breaks a frangible seal on the bottle. After the contents of the bottle are expended the bottle may be withdrawn and replaced with another charge bottle by a vacuum lock arrangement in conjunction with an arm for manipulating the bottle.

  12. ION SOURCE

    DOEpatents

    Brobeck, W.M.

    1959-04-14

    This patent deals with calutrons and more particularly to an arrangement therein whereby charged bottles in a calutron source unit may be replaced without admitting atmospheric air to the calutron vacuum chamber. As described, an ion unit is disposed within a vacuum tank and has a reservoir open toward a wall of the tank. A spike projects from thc source into the reservoir. When a charge bottle is placed in the reservoir, the spike breaks a frangible seal on the bottle. After the contents of the bottle are expended the bottle may be withdrawn and replaced with another charge bottle by a varuum lock arrangement in conjunction with an arm for manipulating the bottle.

  13. New conditioning procedure derived from operating experience with the Common Long-Pulse Ion Source

    SciTech Connect

    Scoville, B.G.; Madruga, M.; Hong, R.M.; Phillips, J.C.

    1993-10-01

    The DIII-D neutral beam system utilizes an 80 kV version of the Common Long-Pulse Ion Source designed by Lawrence Berkeley Laboratories (LBL) and originally built by RCA. Eight of these ion sources are mounted on four beamlines to provide a total of 20 MW of injected deuterium neutral power to the DIII-D tokamak. To support the DIII-D one-shift operation, neutral beams must be readied in a relatively short period of time each day, typically one hour. During non-operating periods conditioning time for the ion sources is limited, due to the costs of associated support services and the need to perform corrective and preventive maintenance. The experience gained over a six year period has resulted in finely tuned procedures for the conditioning and operation of these ion sources. Recently, an ion source was conditioned which had been accidentally filled with water for several days, resulting in surface corrosion and deconditioning of the grids and surfaces. The method of successful recovery along with data, experience and procedures derived this event and normal operations will be detailed and discussed.

  14. Low-emittance uniform density Cs sup + sources for heavy ion fusion accelerators studies

    SciTech Connect

    Eylon, S.; Henestroza, E.; Garvey, T.; Johnson, R.; Chupp, W.

    1991-04-01

    Low-emittance (high-brightness) Cs{sup +} thermionic sources were developed for the heavy ion induction linac experiment MBE-4 at LBL. The MBE-4 linac accelerates four 10 mA beams from 200 ke V to 900 ke V while amplifying the current up to a factor of nine. Recent studies of the transverse beam dynamics suggested that characteristics of the injector geometry were contributing to the normalized transverse emissions growth. Phase-space and current density distribution measurements of the beam extracted from the injector revealed overfocusing of the outermost rays causing a hollow density profile. We shall report on the performance of a 5 mA scraped beam source (which eliminates the outermost beam rays in the diode) and on the design of an improved 10 mA source. The new source is based on EGUN calculations which indicated that a beam with good emissions and uniform current density could be obtained by modifying the cathode Pierce electrodes and using a spherical emitting surface. The measurements of the beam current density profile on a test stand were found to be in agreement with the numerical simulations. 3 refs., 6 figs.

  15. Radiation source

    DOEpatents

    Thode, Lester E.

    1981-01-01

    A device and method for relativistic electron beam heating of a high-density plasma in a small localized region. A relativistic electron beam generator or accelerator produces a high-voltage electron beam which propagates along a vacuum drift tube and is modulated to initiate electron bunching within the beam. The beam is then directed through a low-density gas chamber which provides isolation between the vacuum modulator and the relativistic electron beam target. The relativistic beam is then applied to a high-density target plasma which typically comprises DT, DD, or similar thermonuclear gas at a density of 10.sup.17 to 10.sup.20 electrons per cubic centimeter. The target gas is ionized prior to application of the relativistic electron beam by means of a laser or other preionization source to form a plasma. Utilizing a relativistic electron beam with an individual particle energy exceeding 3 MeV, classical scattering by relativistic electrons passing through isolation foils is negligible. As a result, relativistic streaming instabilities are initiated within the high-density target plasma causing the relativistic electron beam to efficiently deposit its energy into a small localized region of the high-density plasma target.

  16. LBL/Industry Heterogeneous Reservoir Performance Definition Project

    SciTech Connect

    Benson, S.M.; Majer, E.L.; Long, J.C.S.

    1993-12-31

    In this paper the investigator discusses hydrologic and seismic characterization of a fractured limestone and shale/sandstone formations based on a set of interference test data and vertical seismic profile (VSP)/tomographic imaging. Numerical inversions have been carried to build conceptual models for the Ft. Riley formation based on ``equivalent discontinuum`` and ``variable aperture continuum`` approaches. The analysis suggests the following conclusions: Stochastic inverse approaches were successful in reproducing the transient pressure behavior at the pumping and observation wells and appear to be viable means for characterizing fractured formation. The conceptual models for the Ft. Riley formation derived based on both continuum as well as discontinuum approaches indicate presence of a preferential pathway between wells GW-2 and GW-5 to the north of well GW-3. An attempt was made to verify the conceptual models by predicting the build data during the test Pump 58. The field data was affected by rainfall; however, the conceptual models appear to generate the expected trend. Multi-component VSP is useful for determining fracture orientation. High frequency (up to 5000 hz) imaging of the subsurface is possible at moderate scales (few hundred meters). P-wave imaging of fractured rocks using traveltime and amplitude studies give useful information on fracture density, location, and orientation.

  17. Progress report on LBL's numerical modeling studies on Cerro Prieto

    SciTech Connect

    Halfman-Dooley, S.E.; Lippman, M.J.; Bodvarsson, G.S.

    1989-04-01

    An exploitation model of the Cerro Prieto geothermal system is needed to assess the energy capacity of the field, estimate its productive lifetime and develop an optimal reservoir management plan. The model must consider the natural state (i.e., pre-exploitation) conditions of the system and be able to predict changes in the reservoir thermodynamic conditions (and fluid chemistry) in response to fluid production (and injection). This paper discusses the results of a three-dimensional numerical simulation of the natural state conditions of the Cerro Prieto field and compares computed and observed pressure and temperature/enthalpy changes for the 1973--1987 production period. 16 refs., 24 figs., 2 tabs.

  18. Optimizing proton therapy at the LBL medical accelerator. Final report

    SciTech Connect

    Alonso, J.

    1992-03-01

    This Grant has marked the beginning of a multi-year study process expected to lead to design and construction of at least one, possibly several hospital-based proton therapy facilities in the United States.

  19. Optimizing proton therapy at the LBL medical accelerator

    SciTech Connect

    Alonso, J.

    1992-03-01

    This Grant has marked the beginning of a multi-year study process expected to lead to design and construction of at least one, possibly several hospital-based proton therapy facilities in the United States.

  20. Monitoring the source monitoring.

    PubMed

    Luna, Karlos; Martín-Luengo, Beatriz

    2013-11-01

    The hypothesis that the retrieval of correct source memory cues, those leading to a correct source attribution, increases confidence, whereas the retrieval of incorrect source memory cues, those leading to a source misattribution, decreases confidence was tested. Four predictions were derived from this hypothesis: (1) confidence should be higher for correct than incorrect source attribution except; (2) when no source cues are retrieved; (3) only the source misattributions inferred from the retrieval of incorrect source cues will be rated with low confidence; and (4) the number of source cues retrieved, either correct or incorrect, will affect the confidence in the source attributions. To test these predictions, participants read two narratives from two witnesses to a bank robbery, a customer and a teller. Then, participants completed a source monitoring test with four alternatives, customer, teller, both, or neither, and rated their confidence in their source attribution. Results supported the first three predictions, but they also suggested that the number of correct source monitoring cues retrieved did not play a role in the monitoring of the accuracy of the source attributions. Attributions made from the recovery of incorrect source cues could be tagged as dubious or uncertain, thus leading to lowered confidence irrespective of the number of incorrect source cues or whether another correct source cue was also recovered. This research has potential applications for eyewitness memory because it shows that confidence can be an indicator of the accuracy of a source attribution. PMID:23553316

  1. LISA source confusion

    SciTech Connect

    Crowder, Jeff; Cornish, Neil J.

    2004-10-15

    The Laser Interferometer Space Antenna will detect thousands of gravitational wave sources. Many of these sources will be overlapping in the sense that their signals will have a nonzero cross correlation. Such overlaps lead to source confusion, which adversely affects how well we can extract information about the individual sources. Here we study how source confusion impacts parameter estimation for galactic compact binaries, with emphasis on the effects of the number of overlaping sources, the time of observation, the gravitational wave frequencies of the sources, and the degree of the signal correlations. Our main findings are that the parameter resolution decays exponentially with the number of overlapping sources and superexponentially with the degree of cross correlation. We also find that an extended mission lifetime is key to disentangling the source confusion as the parameter resolution for overlapping sources improves much faster than the usual square root of the observation time.

  2. Modeling Frequency Comb Sources

    NASA Astrophysics Data System (ADS)

    Li, Feng; Yuan, Jinhui; Kang, Zhe; Li, Qian; Wai, P. K. A.

    2016-06-01

    Frequency comb sources have revolutionized metrology and spectroscopy and found applications in many fields. Stable, low-cost, high-quality frequency comb sources are important to these applications. Modeling of the frequency comb sources will help the understanding of the operation mechanism and optimization of the design of such sources. In this paper,we review the theoretical models used and recent progress of the modeling of frequency comb sources.

  3. Brain protein deciphered at Advanced Light Source

    SciTech Connect

    2010-01-01

    This computer-generated model of a rat glutamate receptor is the first complete portrait of this important link in the nervous system. At the top of the Y-shaped protein, a pair of molecules splay outward like diverging prongs. The bottom section, which is embedded in a neuronal membrane, houses the ion channel. The resolution of this image is 3.6 angstroms per pixel, or just under four ten-billionths of a meter per image unit. http://newscenter.lbl.gov/feature-stories/2010/01/21/glutamate-receptor/

  4. The Chandra Source Catalog

    NASA Astrophysics Data System (ADS)

    Evans, Ian N.; Primini, F. A.; Glotfelty, K. J.; Anderson, C. S.; Bonaventura, N. R.; Chen, J. C.; Davis, J. E.; Doe, S. M.; Evans, J. D.; Fabbiano, G.; Galle, E.; Gibbs, D. G.; Grier, J. D.; Hain, R.; Hall, D. M.; Harbo, P. N.; He, X.; Houck, J. C.; Karovska, M.; Lauer, J.; McCollough, M. L.; McDowell, J. C.; Miller, J. B.; Mitschang, A. W.; Morgan, D. L.; Nichols, J. S.; Nowak, M. A.; Plummer, D. A.; Refsdal, B. L.; Rots, A. H.; Siemiginowska, A. L.; Sundheim, B. A.; Tibbetts, M. S.; Van Stone, D. W.; Winkelman, S. L.; Zografou, P.

    2009-01-01

    The Chandra Source Catalog (CSC) is the definitive catalog of X-ray sources detected by the Chandra X-ray Observatory. When compared to all previous and current X-ray missions, Chandra breaks the resolution barrier with an arcsecond scale on-axis point spread function. The combination of excellent spatial resolution, a reasonable field of view, and low instrumental background translate into a high detectable-source density, with low confusion and good astrometry. The wealth of information that can be extracted from identified serendipitous sources is a powerful and valuable resource for astronomy. The aim of the CSC is to disseminate this wealth of information by characterizing the X-ray sky as seen by Chandra. The CSC provides simple access to Chandra data for individual sources or sets of sources matching user-specified search criteria. The catalog is intended to satisfy the needs of a broad-based group of scientists, including those who may be less familiar with astronomical data analysis in the X-ray regime. For each detected X-ray source, the catalog lists the source position and a detailed set of source properties, including multi-band aperture fluxes, X-ray colors and hardness ratios, spectra, temporal variability information, and source extent estimates. In addition to these traditional elements, the catalog includes file-based data products that can be manipulated interactively, including images, photon event lists, light curves, and spectra for each source individually from each observation in which a source is detected. The first release of the CSC includes information for 150,000 X-ray sources detected in a subset of public imaging observations from the first eight years of the Chandra mission. Only point sources, and compact sources with extents < 30 arcsec, are included. Highly extended sources, and sources located in selected fields containing bright, highly extended sources, are excluded from this release. This work is supported by NASA contract NAS

  5. The Chandra Source Catalog

    NASA Astrophysics Data System (ADS)

    Evans, Ian N.; Primini, Francis A.; Glotfelty, Kenny J.; Anderson, Craig S.; Bonaventura, Nina R.; Chen, Judy C.; Davis, John E.; Doe, Stephen M.; Evans, Janet D.; Fabbiano, Giuseppina; Galle, Elizabeth C.; Gibbs, Danny G., II; Grier, John D.; Hain, Roger M.; Hall, Diane M.; Harbo, Peter N.; (Helen He, Xiangqun; Houck, John C.; Karovska, Margarita; Kashyap, Vinay L.; Lauer, Jennifer; McCollough, Michael L.; McDowell, Jonathan C.; Miller, Joseph B.; Mitschang, Arik W.; Morgan, Douglas L.; Mossman, Amy E.; Nichols, Joy S.; Nowak, Michael A.; Plummer, David A.; Refsdal, Brian L.; Rots, Arnold H.; Siemiginowska, Aneta; Sundheim, Beth A.; Tibbetts, Michael S.; Van Stone, David W.; Winkelman, Sherry L.; Zografou, Panagoula

    2010-07-01

    The Chandra Source Catalog (CSC) is a general purpose virtual X-ray astrophysics facility that provides access to a carefully selected set of generally useful quantities for individual X-ray sources, and is designed to satisfy the needs of a broad-based group of scientists, including those who may be less familiar with astronomical data analysis in the X-ray regime. The first release of the CSC includes information about 94,676 distinct X-ray sources detected in a subset of public Advanced CCD Imaging Spectrometer imaging observations from roughly the first eight years of the Chandra mission. This release of the catalog includes point and compact sources with observed spatial extents lsim30''. The catalog (1) provides access to the best estimates of the X-ray source properties for detected sources, with good scientific fidelity, and directly supports scientific analysis using the individual source data; (2) facilitates analysis of a wide range of statistical properties for classes of X-ray sources; and (3) provides efficient access to calibrated observational data and ancillary data products for individual X-ray sources, so that users can perform detailed further analysis using existing tools. The catalog includes real X-ray sources detected with flux estimates that are at least 3 times their estimated 1σ uncertainties in at least one energy band, while maintaining the number of spurious sources at a level of lsim1 false source per field for a 100 ks observation. For each detected source, the CSC provides commonly tabulated quantities, including source position, extent, multi-band fluxes, hardness ratios, and variability statistics, derived from the observations in which the source is detected. In addition to these traditional catalog elements, for each X-ray source the CSC includes an extensive set of file-based data products that can be manipulated interactively, including source images, event lists, light curves, and spectra from each observation in which a

  6. The Chandra Source Catalog

    NASA Astrophysics Data System (ADS)

    Evans, Ian; Primini, Francis A.; Glotfelty, Kenny J.; Anderson, Craig S.; Bonaventura, Nina R.; Chen, Judy C.; Davis, John E.; Doe, Stephen M.; Evans, Janet D.; Fabbiano, Giuseppina; Galle, Elizabeth C.; Gibbs, Danny G., II; Grier, John D.; Hain, Roger; Hall, Diane M.; Harbo, Peter N.; He, Xiang Qun (Helen); Houck, John C.; Karovska, Margarita; Kashyap, Vinay L.; Lauer, Jennifer; McCollough, Michael L.; McDowell, Jonathan C.; Miller, Joseph B.; Mitschang, Arik W.; Morgan, Douglas L.; Mossman, Amy E.; Nichols, Joy S.; Nowak, Michael A.; Plummer, David A.; Refsdal, Brian L.; Rots, Arnold H.; Siemiginowska, Aneta L.; Sundheim, Beth A.; Tibbetts, Michael S.; van Stone, David W.; Winkelman, Sherry L.; Zografou, Panagoula

    2009-09-01

    The first release of the Chandra Source Catalog (CSC) was published in 2009 March, and includes information about 94,676 X-ray sources detected in a subset of public ACIS imaging observations from roughly the first eight years of the Chandra mission. This release of the catalog includes point and compact sources with observed spatial extents <˜30''.The CSC is a general purpose virtual X-ray astrophysics facility that provides access to a carefully selected set of generally useful quantities for individual X-ray sources, and is designed to satisfy the needs of a broad-based group of scientists, including those who may be less familiar with astronomical data analysis in the X-ray regime.The catalog (1) provides access to the best estimates of the X-ray source properties for detected sources, with good scientific fidelity, and directly supports medium sophistication scientific analysis on using the individual source data; (2) facilitates analysis of a wide range of statistical properties for classes of X-ray sources; (3) provides efficient access to calibrated observational data and ancillary data products for individual X-ray sources, so that users can perform detailed further analysis using existing tools; and (4) includes real X-ray sources detected with flux significance greater than a predefined threshold, while maintaining the number of spurious sources at an acceptable level. For each detected X-ray source, the CSC provides commonly tabulated quantities, including source position, extent, multi-band fluxes, hardness ratios, and variability statistics, derived from the observations in which the source is detected. In addition to these traditional catalog elements, for each X-ray source the CSC includes an extensive set of file-based data products that can be manipulated interactively, including source images, event lists, light curves, and spectra from each observation in which a source is detected.

  7. Self-assembled films containing crude extract of avocado as a source of tyrosinase for monophenol detection.

    PubMed

    Vieira, Nirton C S; Ferreira, Reginaldo A; da Cruz Rodrigues, Valquiria; Guimarães, Francisco E G; de Queiroz, Alvaro A A

    2013-10-01

    This paper reports on the use of the crude extract of avocado (CEA) fruit (Persea americana) as a source of tyrosinase enzyme. CEA was immobilized via layer by layer (LbL) technique onto indium tin oxide (ITO) substrates and applied in the detection of monophenol using a potentiometric biosensor. Poly(propylene imine) dendrimer of generation 3 (PPI-G3) was used as a counter ion in the layer by layer process due to its highly porous structure and functional groups suitable for enzyme linkage. After the immobilization of the crude CEA as multilayered films, standard samples of monophenol were detected in the 0.25-4.00 mM linear range with approximately 28 mV mM(-1) of sensitivity. This sensitivity is 14 times higher than the values found in the literature for a similar system. The results show that it is possible to obtain efficient and low-cost biosensors for monophenol detection using potentiometric transducers and alternative sources of enzymes without purification. PMID:23910293

  8. Who goes there. A dialogue of questions and answers about benign hacking. [Securing access to computer from outside sources

    SciTech Connect

    Stevens, D.F.

    1987-04-01

    On August 23, 1986, it was noticed that the accounting files for one of LBL's computing systems failed to balance. On August 24, we received word that an unauthorized person was attempting entry into a US Navy computer from LBL. Preliminary investigation indicated that LBL was the victim of a benign hacker, where ''benign'' is used in the medical sense. It was thought that the perpetrator was a graduate student from a neighboring university, and that it would provide a useful object lesson to other such folk if he were caught and admonished. LBL therefore embarked upon a journey of detection and containment instead of prevention. That journey continues today, having led first across the country, then across the Atlantic. In the course of the journey we have gathered a number of observations that should be of interest to anyone running a computer with any connection to the outside world.

  9. European Spallation Source

    NASA Astrophysics Data System (ADS)

    Eshraqi, Mohammad; McGinnis, David; Lindroos, Mats

    The following sections are included: * Neutron usage and historical background * Spallation * History of spallation sources * The ESS facility * The ESS linac * Beam physics * The front-end and the normal conducting linac * Superconducting linac * RF sources * Summary * References

  10. Source Water Quality Monitoring

    EPA Science Inventory

    Presentation will provide background information on continuous source water monitoring using online toxicity monitors and cover various tools available. Conceptual and practical aspects of source water quality monitoring will be discussed.

  11. Artificial light sources.

    PubMed

    Anderson, T F

    1986-04-01

    A wide variety of artificial light sources exists for use in the diagnosis and treatment of photosensitivity disorders. A discussion of the advantages and disadvantages of these light sources (including gas discharge arcs, fluorescent lamps, and other apparatus) illustrates the importance of matching the emission spectrum of the light source, the spectral response of the radiometer, and the photobiologic action spectrum. Environmental and occupational exposure to artificial light sources may contribute to photosensitivity disorders. PMID:3955892

  12. Theory on acoustic sources

    NASA Technical Reports Server (NTRS)

    Wright, S. E.

    1978-01-01

    A theory is described for the radiation emission emission from acoustic multipole sources. The sources can be stationary or moving at speeds including supersonic and experience stationary or moving disturbances. The effect of finite source distributions and disturbances is investigated as well as the manner in which they interact. Distinction is made between source distributions that responsed as a function of time and those that respond as a function of space.

  13. Familiarity in Source Memory

    PubMed Central

    Mollison, Matthew V.; Curran, Tim

    2012-01-01

    Familiarity and recollection are thought to be separate processes underlying recognition memory. Event-related potentials (ERPs) dissociate these processes, with an early (approximately 300–500 ms) frontal effect relating to familiarity (the FN400) and a later (500–800 ms) parietal old/new effect relating to recollection. It has been debated whether source information for a studied item (i.e., contextual associations from when the item was previously encountered) is only accessible through recollection, or whether familiarity can contribute to successful source recognition. It has been shown that familiarity can assist in perceptual source monitoring when the source attribute is an intrinsic property of the item (e.g., an object’s surface color), but few studies have examined its contribution to recognizing extrinsic source associations. Extrinsic source associations were examined in three experiments involving memory judgments for pictures of common objects. In Experiment 1, source information was spatial and results suggested that familiarity contributed to accurate source recognition: the FN400 ERP component showed a source accuracy effect, and source accuracy was above chance for items judged to only feel familiar. Source information in Experiment 2 was an extrinsic color association; source accuracy was at chance for familiar items and the FN400 did not differ between correct and incorrect source judgments. Experiment 3 replicated the results using a within-subjects manipulation of spatial vs. color source. Overall, the results suggest that familiarity’s contribution to extrinsic source monitoring depends on the type of source information being remembered. PMID:22789677

  14. Extragalactic Radio Sources

    ERIC Educational Resources Information Center

    Kellerman, Kenneth I.

    1973-01-01

    Discusses new problems arising from the growing observational data through radio telescope arrays, involving the origin of radio sources, apparent superluminal velocities, conversion of radio sources to relativistic particles, and the nature of compact opaque and extended transparent sources. New physics may be needed to answer these cosmological…

  15. Sources of pulsed radiation

    SciTech Connect

    Sauer, M.C. Jr.

    1981-01-01

    Characteristics of various sources of pulsed radiation are examined from the viewpoint of their importance to the radiation chemist, and some examples of uses of such sources are mentioned. A summary is given of the application of methods of physical dosimetry to pulsed sources, and the calibration of convenient chemical dosimeters by physical dosimetry is outlined. 7 figures, 1 table.

  16. Investigating Primary Source Literacy

    ERIC Educational Resources Information Center

    Archer, Joanne; Hanlon, Ann M.; Levine, Jennie A.

    2009-01-01

    Primary source research requires students to acquire specialized research skills. This paper presents results from a user study testing the effectiveness of a Web guide designed to convey the concepts behind "primary source literacy". The study also evaluated students' strengths and weaknesses when conducting primary source research. (Contains 3…

  17. The Chandra Source Catalog

    NASA Astrophysics Data System (ADS)

    Evans, Ian N.; Primini, F. A.; Glotfelty, K. J.; Anderson, C. S.; Bonaventura, N. R.; Chen, J. C.; Davis, J. E.; Doe, S. M.; Evans, J. D.; Fabbiano, G.; Galle, E. C.; Gibbs, D. G., II; Grier, J. D.; Hain, R. M.; Hall, D. M.; Harbo, P. N.; He, X.; Houck, J. C.; Karovska, M.; Kashyap, V. L.; Lauer, J.; McCollough, M. L.; McDowell, J. C.; Miller, J. B.; Mitschang, A. W.; Morgan, D. L.; Mossman, A. E.; Nichols, J. S.; Nowak, M. A.; Plummer, D. A.; Refsdal, B. L.; Rots, A. H.; Siemiginowska, A.; Sundheim, B. A.; Tibbetts, M. S.; Van Stone, D. W.; Winkelman, S. L.; Zografou, P.

    2010-03-01

    The Chandra Source Catalog (CSC) is a general purpose virtual X-ray astrophysics facility that provides access to a carefully selected set of generally useful quantities for individual X-ray sources, and is designed to satisfy the needs of a broad-based group of scientists, including those who may be less familiar with astronomical data analysis in the X-ray regime. The first release of the CSC includes information about 94,676 distinct X-ray sources detected in a subset of public ACIS imaging observations from roughly the first eight years of the Chandra mission. This release of the catalog includes point and compact sources with observed spatial extents < 30". The catalog (1) provides access to estimates of the X-ray source properties for detected sources with good scientific fidelity; (2) facilitates analysis of a wide range of statistical properties for classes of X-ray sources; and (3) provides efficient access to calibrated observational data and ancillary data products for individual X-ray sources. The catalog includes real X-ray sources detected with flux estimates that are at least 3 times their estimated 1σ uncertainties in at least one energy band, while maintaining the number of spurious sources at a level of < 1 false source per field for a 100 ks observation. For each detected source, the CSC provides commonly tabulated quantities, including source position, extent, multi-band fluxes, hardness ratios, and variability statistics. In addition, for each X-ray source the CSC includes an extensive set of file-based data products that can be manipulated interactively, including source images, event lists, light curves, and spectra. Support for development of the CSC is provided by the National Aeronautics and Space Administration through the Chandra X-ray Center, which is operated by the Smithsonian Astrophysical Observatory for and on behalf of the National Aeronautics and Space Administration under contract NAS 8-03060.

  18. 600 eV falcon-linac thomson x-ray source

    SciTech Connect

    Crane, J K; LeSage, G P; Ditmire, T; Cross, R; Wharton, K; Moffitt, K; Cowan, T E; Hays, G; Tsai, V; Anderson, G; Shuttlesworth, R; Springer, P

    2000-12-15

    The advent of 3rd generation light sources such as the Advanced Light Source (ALS) at LBL, and the Advanced Photon Source at Argonne, have produced a revolution in x-ray probing of dense matter during the past decade. These machines use electron-synchrotrons in conjunction with undulator stages to produce 100 psec x-ray pulses with photon energies of several kiloelectronvolts (keV). The applications for x-ray probing of matter are numerous and diverse with experiments in medicine and biology, semiconductors and materials science, and plasma and solid state physics. In spite of the success of the 3rd generation light sources there is strong motivation to push the capabilities of x-ray probing into new realms, requiring shorter pulses, higher brightness and harder x-rays. A 4th generation light source, the Linac Coherent Light Source (LCLS), is being considered at the Stanford Linear Accelerator [1]. The LCLS will produce multi-kilovolt x-rays of subpicosecond duration that are 10 orders of magnitude brighter than today's 3rd generation light sources.[1] Although the LCLS will provide unprecedented capability for performing time-resolved x-ray probing of ultrafast phenomena at solid densities, this machine will not be completed for many years. In the meantime there is a serious need for an ultrashort-pulse, high-brightness, hard x-ray source that is capable of probing deep into high-Z solid materials to measure dynamic effects that occur on picosecond time scales. Such an instrument would be ideal for probing the effects of shock propagation in solids using Bragg and Laue diffraction. These techniques can be used to look at phase transitions, melting and recrystallization, and the propagation of defects and dislocations well below the surface in solid materials. [2] These types of dynamic phenomena undermine the mechanical properties of metals and are of general interest in solid state physics, materials science, metallurgy, and have specific relevance to stockpile

  19. DC source assemblies

    DOEpatents

    Campbell, Jeremy B; Newson, Steve

    2013-02-26

    Embodiments of DC source assemblies of power inverter systems of the type suitable for deployment in a vehicle having an electrically grounded chassis are provided. An embodiment of a DC source assembly comprises a housing, a DC source disposed within the housing, a first terminal, and a second terminal. The DC source also comprises a first capacitor having a first electrode electrically coupled to the housing, and a second electrode electrically coupled to the first terminal. The DC source assembly further comprises a second capacitor having a first electrode electrically coupled to the housing, and a second electrode electrically coupled to the second terminal.

  20. Neuromagnetic source reconstruction

    SciTech Connect

    Lewis, P.S.; Mosher, J.C.; Leahy, R.M.

    1994-12-31

    In neuromagnetic source reconstruction, a functional map of neural activity is constructed from noninvasive magnetoencephalographic (MEG) measurements. The overall reconstruction problem is under-determined, so some form of source modeling must be applied. We review the two main classes of reconstruction techniques-parametric current dipole models and nonparametric distributed source reconstructions. Current dipole reconstructions use a physically plausible source model, but are limited to cases in which the neural currents are expected to be highly sparse and localized. Distributed source reconstructions can be applied to a wider variety of cases, but must incorporate an implicit source, model in order to arrive at a single reconstruction. We examine distributed source reconstruction in a Bayesian framework to highlight the implicit nonphysical Gaussian assumptions of minimum norm based reconstruction algorithms. We conclude with a brief discussion of alternative non-Gaussian approachs.

  1. Markov information sources

    NASA Technical Reports Server (NTRS)

    Massey, J. L.

    1975-01-01

    A regular Markov source is defined as the output of a deterministic, but noisy, channel driven by the state sequence of a regular finite-state Markov chain. The rate of such a source is the per letter uncertainty of its digits. The well-known result that the rate of a unifilar regular Markov source is easily calculable is demonstrated, where unifilarity means that the present state of the Markov chain and the next output of the deterministic channel uniquely determine the next state. At present, there is no known method to calculate the rate of a nonunifilar source. Two tentative approaches to this unsolved problem are given, namely source identical twins and the master-slave source, which appear to shed some light on the question of rate calculation for a nonunifilar source.

  2. Microwave ion source

    DOEpatents

    Leung, Ka-Ngo; Reijonen, Jani; Thomae, Rainer W.

    2005-07-26

    A compact microwave ion source has a permanent magnet dipole field, a microwave launcher, and an extractor parallel to the source axis. The dipole field is in the form of a ring. The microwaves are launched from the middle of the dipole ring using a coaxial waveguide. Electrons are heated using ECR in the magnetic field. The ions are extracted from the side of the source from the middle of the dipole perpendicular to the source axis. The plasma density can be increased by boosting the microwave ion source by the addition of an RF antenna. Higher charge states can be achieved by increasing the microwave frequency. A xenon source with a magnetic pinch can be used to produce intense EUV radiation.

  3. Unveiling Unidentified Fermi Sources

    NASA Astrophysics Data System (ADS)

    Zhang, Lizhong; South Pole Telescope

    2016-01-01

    The Fermi γ-ray Space Telescope (Fermi) has surveyed the entire sky at the highest-energy band of the electromagnetic spectrum. The majority of Fermi sources have counterpart identifications from multi-wavelength large-area surveys, particularly in the radio and x-ray bands. However, around 35% of Fermi sources remain unidentified, a problem exasperated by the low resolution of the telescope. Understanding the nature of unidentified Fermi sources is one of the most pressing problems in γ-ray astronomy. The South Pole Telescope (SPT) has completed a survey covering a 2500 square degrees of the southern extragalactic sky with arcminute resolution at millimeter wavelengths. The mm wavelength is the most efficient means to identify blazars and unidentified Fermi sources. Our analysis shows that the SPT point source catalog provides candidate associations for 40% of the unidentified Fermi sources, showing them to be flat-spectrum radio quasars which are extraordinarily bright at millimeter (mm) wavelengths.

  4. Pulsed spallation Neutron Sources

    SciTech Connect

    Carpenter, J.M.

    1994-12-31

    This paper reviews the early history of pulsed spallation neutron source development at Argonne and provides an overview of existing sources world wide. A number of proposals for machines more powerful than currently exist are under development, which are briefly described. The author reviews the status of the Intense Pulsed Neutron Source, its instrumentation, and its user program, and provides a few examples of applications in fundamental condensed matter physics, materials science and technology.

  5. Pulsed spallation neutron sources

    SciTech Connect

    Carpenter, J.M.

    1996-05-01

    This paper reviews the early history of pulsed spallation neutron source development ar Argonne and provides an overview of existing sources world wide. A number of proposals for machines more powerful than currently exist are under development, which are briefly described. The author reviews the status of the Intense Pulsed Neutron Source, its instrumentation, and its user program, and provide a few examples of applications in fundamental condensed matter physics, materials science and technology.

  6. ION SOURCE FOR CALUTRONS

    DOEpatents

    Tolmie, J.R.

    1958-09-16

    An improvement is presented in ion sources of the type employed in calutron devices. The described ion source has for its inventive contribution the incorporation of a plate-like cathode having the general configuration of a polygon including a given number of apices. When a polyphase source of current has a phase connected to each of the apices, the cathode is heated and rendered electron emissive. This particular cathode configuration is of sturdy construction and provides unuform emission over a considerable area.

  7. Radioisotopic heat source

    DOEpatents

    Sayell, E.H.

    1973-10-23

    A radioisotopic heat source is described which includes a core of heat productive, radioisotopic material, an impact resistant layer of graphite surrounding said core, and a shell of iridium metal intermediate the core and the impact layer. The source may also include a compliant mat of iridium between the core and the iridium shell, as well as an outer covering of iridium metal about the entire heat source. (Official Gazette)

  8. Source and replica calculations

    SciTech Connect

    Whalen, P.P.

    1994-02-01

    The starting point of the Hiroshima-Nagasaki Dose Reevaluation Program is the energy and directional distributions of the prompt neutron and gamma-ray radiation emitted from the exploding bombs. A brief introduction to the neutron source calculations is presented. The development of our current understanding of the source problem is outlined. It is recommended that adjoint calculations be used to modify source spectra to resolve the neutron discrepancy problem.

  9. Dynamic radioactive particle source

    DOEpatents

    Moore, Murray E.; Gauss, Adam Benjamin; Justus, Alan Lawrence

    2012-06-26

    A method and apparatus for providing a timed, synchronized dynamic alpha or beta particle source for testing the response of continuous air monitors (CAMs) for airborne alpha or beta emitters is provided. The method includes providing a radioactive source; placing the radioactive source inside the detection volume of a CAM; and introducing an alpha or beta-emitting isotope while the CAM is in a normal functioning mode.

  10. Rf power sources

    SciTech Connect

    Allen, M.A.

    1988-05-01

    This paper covers RF power sources for accelerator applications. The approach has been with particular customers in mind. These customers are high energy physicists who use accelerators as experimental tools in the study of the nucleus of the atom, and synchrotron light sources derived from electron or positron storage rings. This paper is confined to electron-positron linear accelerators since the RF sources have always defined what is possible to achieve with these accelerators. 11 refs., 13 figs.

  11. Source identification with GLAST

    SciTech Connect

    Lonjou, Vincent; Knoedlseder, Juergen

    2007-07-12

    With more than 50% of unidentified sources, the third EGRET catalogue reflects the complexity of source identification in the GeV domain. In that context, we developed a dedicated GLAST ScienceTool dubbed gtsrcid for the general purpose of source identification. gtsrcid has been designed in a very flexible way and allows cross correlation with any counterpart catalogue using user-definable figures-of-merit. Our source identification strategy, the results for DC2 as well as possible improvements of our identification procedures are presented.

  12. Improved ion source

    DOEpatents

    Leung, K.N.; Ehlers, K.W.

    1982-05-04

    A magnetic filter for an ion source reduces the production of undesired ion species and improves the ion beam quality. High-energy ionizing electrons are confined by the magnetic filter to an ion source region, where the high-energy electrons ionize gas molecules. One embodiment of the magnetic filter uses permanent magnets oriented to establish a magnetic field transverse to the direction of travel of ions from the ion source region to the ion extraction region. In another embodiment, low energy 16 eV electrons are injected into the ion source to dissociate gas molecules and undesired ion species into desired ion species,

  13. Opportunities for high aspect ratio micro-electro-magnetic-mechanical systems (HAR-MEMMS) at Lawrence Berkeley Laboratory

    SciTech Connect

    Hunter, S.

    1993-10-01

    This report contains viewgraphs on the following topics: Opportunities for HAR-MEMMS at LBL; Industrial Needs and Opportunities; Deep Etch X-ray Lithography; MEMS Activities at BSAC; DNA Amplification with Microfabricated Reaction Chamber; Electrochemistry Research at LBL; MEMS Activities at LLNL; Space Microsensors and Microinstruments; The Advanced Light Source; Institute for Micromaching; IBM MEMS Interests; and Technology Transfer Opportunities at LBL.

  14. Workshop on detectors for third-generation synchrotron sources: Proceedings

    SciTech Connect

    1994-12-01

    The aims of the workshop were (1) to acquaint APS users with current R and D being carried out on detectors, (2) to identify new detector systems possible during the next five years, (3) to identify new detectors theoretically possible in the future, (4) to stimulate interactions between user groups and detector developers, and (5) to obtain recommendations from expert panels on technical issues needing resolution. Development of detectors at ESRF, Spring-8, BNL, CERN and LBL are included.

  15. Noncontact Electromagnetic Vibration Source

    NASA Technical Reports Server (NTRS)

    Namkung, Min; Fulton, James P.; Wincheski, Buzz A.

    1994-01-01

    Metal aircraft skins scanned rapidly in vibration tests. Relatively simple combination of permanent magnets and electromagnet serves as noncontact vibration source for nondestructive testing of metal aircraft skins. In test, source excites vibrations, and vibration waveforms measured, then analyzed for changes in resonances signifying cracks and other flaws.

  16. Acoustic emission source location

    NASA Astrophysics Data System (ADS)

    Promboon, Yajai

    The objective of the research program was development of reliable source location techniques. The study comprised two phases. First, the research focused on development of source location methods for homogeneous plates. The specimens used in the program were steel railroad tank cars. Source location methods were developed and demonstrated for empty and water filled tanks. The second phase of the research was an exploratory study of source location method for fiber reinforced composites. Theoretical analysis and experimental measurement of wave propagation were carried out. This data provided the basis for development of a method using the intersection of the group velocity curves for the first three wave propagation modes. Simplex optimization was used to calculate the location of the source. Additional source location methods have been investigated and critically examined. Emphasis has been placed on evaluating different methods for determining the time of arrival of a wave. The behavior of wave in a water filled tank was studied and source location methods suitable for use in this situation have been examined through experiment and theory. Particular attention is paid to the problem caused by leaky Lamb waves. A preliminary study into the use of neural networks for source location in fiber reinforced composites was included in the research program. A preliminary neural network model and the results from training and testing data are reported.

  17. Leading Education Reference Sources.

    ERIC Educational Resources Information Center

    Spencer, Michael D.

    This annotated bibliography focuses on, but is not limited to, reference sources on education found in the library at St. Bonaventure University, New York. The ERIC database leads the list of leading education reference sources. Also mentioned are the "Thesaurus of ERIC Descriptors" and the Academic Index (InfoTrak) computer system. Other…

  18. Energy Sources and Development.

    ERIC Educational Resources Information Center

    Crank, Ron

    This instructional unit is one of 10 developed by students on various energy-related areas that deals specifically with energy sources and development. Its objective is for the student to be able to discuss energy sources and development related to the historical perspective, biological development, current aspects, and future expectations…

  19. New Source Performance Standards

    ERIC Educational Resources Information Center

    Jenkins, Richard E.; McCutchen, Gary D.

    1972-01-01

    This feature article outlines the concept and procedures followed in establishing performance standards for new emission sources and summarizes the standards that have been established to date. Five source catagories are enumerated: fossil fuel-fired steam generators, municipal incinerators, Portland cement plants, nitric acid plants, and sulfuric…

  20. 1972 Microfilm Source Book.

    ERIC Educational Resources Information Center

    1972

    The 1972 Microfilm Source Book has been designed to give sources of supply for important services and equipment related to microfilm. Events in the microfilm industry during 1971 are reviewed first, and a calendar is provided of major meetings and conferences held during 1972. The next section contains an index to products which lists them…

  1. Creating Open Source Conversation

    ERIC Educational Resources Information Center

    Sheehan, Kate

    2009-01-01

    Darien Library, where the author serves as head of knowledge and learning services, launched a new website on September 1, 2008. The website is built with Drupal, an open source content management system (CMS). In this article, the author describes how she and her colleagues overhauled the library's website to provide an open source content…

  2. Open Source Vision

    ERIC Educational Resources Information Center

    Villano, Matt

    2006-01-01

    Increasingly, colleges and universities are turning to open source as a way to meet their technology infrastructure and application needs. Open source has changed life for visionary CIOs and their campus communities nationwide. The author discusses what these technologists see as the benefits--and the considerations.

  3. Spherical ion source

    NASA Technical Reports Server (NTRS)

    Hall, L. G.

    1969-01-01

    Radial focusing of electrons in ion source produces greater ion densities, resulting in higher resolution and focus capability for a given source volume. Electron beam is focused near exit aperture by spherical fields. High density ions allow focusing ion beam to high density at echo, allowing high current through small aperture.

  4. Radiation Source Replacement Workshop

    SciTech Connect

    Griffin, Jeffrey W.; Moran, Traci L.; Bond, Leonard J.

    2010-12-01

    This report summarizes a Radiation Source Replacement Workshop in Houston Texas on October 27-28, 2010, which provided a forum for industry and researchers to exchange information and to discuss the issues relating to replacement of AmBe, and potentially other isotope sources used in well logging.

  5. PORTABLE SOURCE OF RADIOACTIVITY

    DOEpatents

    Goertz, R.C.; Ferguson, K.R.; Rylander, E.W.; Safranski, L.M.

    1959-06-16

    A portable source for radiogiaphy or radiotherapy is described. It consists of a Tl/sup 170/ or Co/sup 60/ source mounted in a rotatable tungsten alloy plug. The plug rotates within a brass body to positions of safety or exposure. Provision is made for reloading and carrying the device safely. (T.R.H.)

  6. Nonpoint Source Pollution.

    PubMed

    Ahmad, Zaki Uddin; Sakib, Salman; Gang, Daniel Dianchen

    2016-10-01

    Research advances on non-point source pollution in the year 2015 have been depicted in this review paper. Nonpoint source pollution is mainly caused by agricultural runoff, urban stormwater, and atmospheric deposition. Modeling techniques of NPS with different tools are reviewed in this article. PMID:27620104

  7. Using Primary Source Documents.

    ERIC Educational Resources Information Center

    Mintz, Steven

    2003-01-01

    Explores the use of primary sources when teaching about U.S. slavery. Includes primary sources from the Gilder Lehrman Documents Collection (New York Historical Society) to teach about the role of slaves in the Revolutionary War, such as a proclamation from Lord Dunmore offering freedom to slaves who joined his army. (CMK)

  8. Radioisotopic heat source

    DOEpatents

    Jones, G.J.; Selle, J.E.; Teaney, P.E.

    1975-09-30

    Disclosed is a radioisotopic heat source and method for a long life electrical generator. The source includes plutonium dioxide shards and yttrium or hafnium in a container of tantalum-tungsten-hafnium alloy, all being in a nickel alloy outer container, and subjected to heat treatment of from about 1570$sup 0$F to about 1720$sup 0$F for about one h. (auth)

  9. Industrial ion source technology

    NASA Technical Reports Server (NTRS)

    Kaufman, H. R.

    1976-01-01

    A 30 cm electron bombardment ion source was designed and fabricated for micromachining and sputtering applications. This source has a multipole magnetic field that employs permanent magnets between permeable pole pieces. An average ion current density of 1 ma/sq cm with 500 eV argon ions was selected as a design operating condition. The ion beam at this operating condition was uniform and well collimated, with an average variation of plus or minus 5 percent over the center 20 cm of the beam at distances up to 30 cm from the ion source. A variety of sputtering applications were undertaken with a small 10 cm ion source to better understand the ion source requirements in these applications. The results of these experimental studies are also included.

  10. On source radiation

    NASA Technical Reports Server (NTRS)

    Levine, H.

    1980-01-01

    The power output from given sources is usually ascertained via an energy flux integral over the normal directions to a remote (far field) surface; an alternative procedure, which utilizes an integral that specifies the direct rate of working by the source on the resultant field, is described and illustrated for both point and continuous source distribution. A comparison between the respective procedures is made in the analysis of sound radiated from a periodic dipole source whose axis performs a periodic plane angular movement about a fixed direction. Thus, adopting a conventional approach, Sretenskii (1956) characterizes the rotating dipole in terms of an infinite number of stationary ones along a pari of orthogonal directions in the plane, and through the far field representation of the latter, arrives at a series development for the instantaneous radiated power, whereas the local manner of power calculation dispenses with the equivalent infinite aggregate of sources and yields a compact analytical result.

  11. Photonic crystal light source

    DOEpatents

    Fleming, James G.; Lin, Shawn-Yu; Bur, James A.

    2004-07-27

    A light source is provided by a photonic crystal having an enhanced photonic density-of-states over a band of frequencies and wherein at least one of the dielectric materials of the photonic crystal has a complex dielectric constant, thereby producing enhanced light emission at the band of frequencies when the photonic crystal is heated. The dielectric material can be a metal, such as tungsten. The spectral properties of the light source can be easily tuned by modification of the photonic crystal structure and materials. The photonic crystal light source can be heated electrically or other heating means. The light source can further include additional photonic crystals that exhibit enhanced light emission at a different band of frequencies to provide for color mixing. The photonic crystal light source may have applications in optical telecommunications, information displays, energy conversion, sensors, and other optical applications.

  12. Piezotube borehole seismic source

    SciTech Connect

    Daley, Tom M; Solbau, Ray D; Majer, Ernest L

    2014-05-06

    A piezoelectric borehole source capable of permanent or semipermanent insertion into a well for uninterrupted well operations is described. The source itself comprises a series of piezoelectric rings mounted to an insulative mandrel internally sized to fit over a section of well tubing, the rings encased in a protective housing and electrically connected to a power source. Providing an AC voltage to the rings will cause expansion and contraction sufficient to create a sonic pulse. The piezoelectric borehole source fits into a standard well, and allows for uninterrupted pass-through of production tubing, and other tubing and electrical cables. Testing using the source may be done at any time, even concurrent with well operations, during standard production.

  13. Pulsed ion beam source

    DOEpatents

    Greenly, John B.

    1997-01-01

    An improved pulsed ion beam source having a new biasing circuit for the fast magnetic field. This circuit provides for an initial negative bias for the field created by the fast coils in the ion beam source which pre-ionize the gas in the source, ionize the gas and deliver the gas to the proper position in the accelerating gap between the anode and cathode assemblies in the ion beam source. The initial negative bias improves the interaction between the location of the nulls in the composite magnetic field in the ion beam source and the position of the gas for pre-ionization and ionization into the plasma as well as final positioning of the plasma in the accelerating gap. Improvements to the construction of the flux excluders in the anode assembly are also accomplished by fabricating them as layered structures with a high melting point, low conductivity material on the outsides with a high conductivity material in the center.

  14. Neutron sources and applications

    SciTech Connect

    Price, D.L.; Rush, J.J.

    1994-01-01

    Review of Neutron Sources and Applications was held at Oak Brook, Illinois, during September 8--10, 1992. This review involved some 70 national and international experts in different areas of neutron research, sources, and applications. Separate working groups were asked to (1) review the current status of advanced research reactors and spallation sources; and (2) provide an update on scientific, technological, and medical applications, including neutron scattering research in a number of disciplines, isotope production, materials irradiation, and other important uses of neutron sources such as materials analysis and fundamental neutron physics. This report summarizes the findings and conclusions of the different working groups involved in the review, and contains some of the best current expertise on neutron sources and applications.

  15. Advanced positron sources

    NASA Astrophysics Data System (ADS)

    Variola, A.

    2014-03-01

    Positron sources are a critical system for the future lepton colliders projects. Due to the large beam emittance at the production and the limitation given by the target heating and mechanical stress, the main collider parameters fixing the luminosity are constrained by the e+ sources. In this context also the damping ring design boundary conditions and the final performance are given by the injected positron beam. At present different schemes are being taken into account in order to increase the production and the capture yield of the positron sources, to reduce the impact of the deposited energy in the converter target and to increase the injection efficiency in the damping ring. The final results have a strong impact not only on the collider performance but also on its cost optimization. After a short introduction illustrating their fundamental role, the basic positron source scheme and the performance of the existing sources will be illustrated. The main innovative designs for the future colliders advanced sources will be reviewed and the different developed technologies presented. Finally the positrons-plasma R&D experiments and the futuristic proposals for positron sources will reviewed.

  16. Biographical Sources for Astronomers

    NASA Astrophysics Data System (ADS)

    Dick, Wolfgang R.

    2006-12-01

    This paper describes the different types of published sources for biographical data from the history of astronomy - well known ones like encyclopaedias, biographical dictionaries, and obituaries, as well as less known ones like membership directories of societies, annual reports, and lists of solar-system nomenclature. Also online sources such as web pages and databases are considered. Existing bio-bibliographies are discussed and a new "Biographical Index of Astronomy" (BIA) is introduced. It lists biographical and bio-bibliographical sources for more than 16,000 persons.

  17. CALUTRON ION SOURCE

    DOEpatents

    Lofgren, E.J.

    1959-02-17

    An improvement is described in ion source mechanisms whereby the source structure is better adapted to withstanid the ravages of heat, erosion, and deterioration concomitant with operation of an ion source of the calutron type. A pair of molybdenum plates define the exit opening of the arc chamber and are in thermal contact with the walls of the chamber. These plates are maintained at a reduced temperature by a pair of copper blocks in thermal conducting contact therewith to form subsequent diverging margins for the exit opening.

  18. Public Geospatial Data Sources

    NASA Astrophysics Data System (ADS)

    Nering, Konrad

    2013-12-01

    In recent years there has been tremendous progress in the field of software for managing geographic information (GIS - Geographic Information System). Data processing capabilities expand with every new version of GIS applications. Similarly, the processing power of computers to process and manage geographic data. Once we have got such a powerful tool, the question arises: where to get the relevant data from? There are many sources of data (public, paid for), but after closer examination it turns out that they are mostly processed data from other sources. In this article I will present the primary source of data that can be used to suit one's needs. All of these data are publicly available

  19. Nuclear electric power sources

    NASA Technical Reports Server (NTRS)

    Singh, J. J.

    1978-01-01

    Measurements on radioactive commercial p-n junction silicon cells show that these units are capable of delivering several hundred microwatts per curie of Am-241 alpha source, indicating their usefulness in such electronic devices as hearing aids, heart pacemakers, electronic watches, delay timers and nuclear dosimeter chargers. It is concluded that the Am-241 sources are superior to the beta sources used previously, because of higher alpha specific ionization and simultaneous production of low energy photons which are easily converted into photoelectrons for additional power.

  20. Microfabricated diffusion source

    DOEpatents

    Oborny, Michael C.; Frye-Mason, Gregory C.; Manginell, Ronald P.

    2008-07-15

    A microfabricated diffusion source to provide for a controlled diffusion rate of a vapor comprises a porous reservoir formed in a substrate that can be filled with a liquid, a headspace cavity for evaporation of the vapor therein, a diffusion channel to provide a controlled diffusion of the vapor, and an outlet to release the vapor into a gas stream. The microfabricated diffusion source can provide a calibration standard for a microanalytical system. The microanalytical system with an integral diffusion source can be fabricated with microelectromechanical systems technologies.

  1. Alternative fuel information sources

    SciTech Connect

    Not Available

    1994-06-01

    This short document contains a list of more than 200 US sources of information (Name, address, phone number, and sometimes contact) related to the use of alternative fuels in automobiles and trucks. Electric-powered cars are also included.

  2. Sources of Assistance.

    ERIC Educational Resources Information Center

    Ahumada, Martin M.; Hefferlin, JB Lon

    1986-01-01

    Information about materials on environmental scanning is offered. Suggestions about sources of data for scanning are provided, organized into six facets of the environment: demographic, economic, political, organizational, technological, and social-cultural. (MLW)

  3. National Synchrotron Light Source

    ScienceCinema

    None

    2010-01-08

    A tour of Brookhaven's National Synchrotron Light Source (NSLS). The NSLS is one of the world's most widely used scientific research facilities, hosting more than 2,500 guest researchers each year. The NSLS provides intense beams of infrared, ultraviole

  4. Calcium source (image)

    MedlinePlus

    Getting enough calcium to keep bones from thinning throughout a person's life may be made more difficult if that person has ... as a tendency toward kidney stones, for avoiding calcium-rich food sources. Calcium deficiency also effects the ...

  5. National Synchrotron Light Source

    SciTech Connect

    2009-03-10

    A tour of Brookhaven's National Synchrotron Light Source (NSLS). The NSLS is one of the world's most widely used scientific research facilities, hosting more than 2,500 guest researchers each year. The NSLS provides intense beams of infrared, ultraviole

  6. Air pollution source identification

    NASA Technical Reports Server (NTRS)

    Fordyce, J. S.

    1975-01-01

    Techniques for air pollution source identification are reviewed, and some results obtained with them are evaluated. Described techniques include remote sensing from satellites and aircraft, on-site monitoring, and the use of injected tracers and pollutants themselves as tracers. The use of a large number of trace elements in ambient airborne particulate matter as a practical means of identifying sources is discussed in detail. Sampling and analysis techniques are described, and it is shown that elemental constituents can be related to specific source types such as those found in the earth's crust and those associated with specific industries. Source identification sytems are noted which utilize charged particle X-ray fluorescence analysis of original field data.

  7. Air pollution source identification

    NASA Technical Reports Server (NTRS)

    Fordyce, J. S.

    1975-01-01

    The techniques available for source identification are reviewed: remote sensing, injected tracers, and pollutants themselves as tracers. The use of the large number of trace elements in the ambient airborne particulate matter as a practical means of identifying sources is discussed. Trace constituents are determined by sensitive, inexpensive, nondestructive, multielement analytical methods such as instrumental neutron activation and charged particle X-ray fluorescence. The application to a large data set of pairwise correlation, the more advanced pattern recognition-cluster analysis approach with and without training sets, enrichment factors, and pollutant concentration rose displays for each element is described. It is shown that elemental constituents are related to specific source types: earth crustal, automotive, metallurgical, and more specific industries. A field-ready source identification system based on time and wind direction resolved sampling is described.

  8. National Synchrotron Light Source

    ScienceCinema

    BNL

    2009-09-01

    A tour of Brookhaven's National Synchrotron Light Source (NSLS), hosted by Associate Laboratory Director for Light Sources, Stephen Dierker. The NSLS is one of the world's most widely used scientific research facilities, hosting more than 2,500 guest researchers each year. The NSLS provides intense beams of infrared, ultraviolet, and x-ray light for basic and applied research in physics, chemistry, medicine, geophysics, environmental, and materials sciences.

  9. Magnetron sputtering source

    DOEpatents

    Makowiecki, D.M.; McKernan, M.A.; Grabner, R.F.; Ramsey, P.B.

    1994-08-02

    A magnetron sputtering source for sputtering coating substrates includes a high thermal conductivity electrically insulating ceramic and magnetically attached sputter target which can eliminate vacuum sealing and direct fluid cooling of the cathode assembly. The magnetron sputtering source design results in greater compactness, improved operating characteristics, greater versatility, and low fabrication cost. The design easily retrofits most sputtering apparatuses and provides for safe, easy, and cost effective target replacement, installation, and removal. 12 figs.

  10. Magnetron sputtering source

    DOEpatents

    Makowiecki, Daniel M.; McKernan, Mark A.; Grabner, R. Fred; Ramsey, Philip B.

    1994-01-01

    A magnetron sputtering source for sputtering coating substrates includes a high thermal conductivity electrically insulating ceramic and magnetically attached sputter target which can eliminate vacuum sealing and direct fluid cooling of the cathode assembly. The magnetron sputtering source design results in greater compactness, improved operating characteristics, greater versatility, and low fabrication cost. The design easily retrofits most sputtering apparatuses and provides for safe, easy, and cost effective target replacement, installation, and removal.

  11. Hubble Source Catalog

    NASA Astrophysics Data System (ADS)

    Lubow, S.; Budavári, T.

    2013-10-01

    We have created an initial catalog of objects observed by the WFPC2 and ACS instruments on the Hubble Space Telescope (HST). The catalog is based on observations taken on more than 6000 visits (telescope pointings) of ACS/WFC and more than 25000 visits of WFPC2. The catalog is obtained by cross matching by position in the sky all Hubble Legacy Archive (HLA) Source Extractor source lists for these instruments. The source lists describe properties of source detections within a visit. The calculations are performed on a SQL Server database system. First we collect overlapping images into groups, e.g., Eta Car, and determine nearby (approximately matching) pairs of sources from different images within each group. We then apply a novel algorithm for improving the cross matching of pairs of sources by adjusting the astrometry of the images. Next, we combine pairwise matches into maximal sets of possible multi-source matches. We apply a greedy Bayesian method to split the maximal matches into more reliable matches. We test the accuracy of the matches by comparing the fluxes of the matched sources. The result is a set of information that ties together multiple observations of the same object. A byproduct of the catalog is greatly improved relative astrometry for many of the HST images. We also provide information on nondetections that can be used to determine dropouts. With the catalog, for the first time, one can carry out time domain, multi-wavelength studies across a large set of HST data. The catalog is publicly available. Much more can be done to expand the catalog capabilities.

  12. Field emission electron source

    DOEpatents

    Zettl, Alexander Karlwalter; Cohen, Marvin Lou

    2000-01-01

    A novel field emitter material, field emission electron source, and commercially feasible fabrication method is described. The inventive field emission electron source produces reliable electron currents of up to 400 mA/cm.sup.2 at 200 volts. The emitter is robust and the current it produces is not sensitive to variability of vacuum or the distance between the emitter tip and the cathode. The novel emitter has a sharp turn-on near 100 volts.

  13. Source Inspection Scheduling Calendar

    NASA Technical Reports Server (NTRS)

    Hollis, Brayden

    2011-01-01

    Quality is an essential component for creating flight hardware travelling through space since the hardware is extremely expensive and cannot be reworked or repaired once launched. An important step in this process is ensuring the quality of hardware procured from Jet Propulsion Laboratory's (JPL) suppliers. An important element of determining supplier quality is source inspection. Source inspections are performed at suppliers' facilities by JPL employeesto ensure that hardware characteristics are acceptable before being covered up and/or delivered to JPL.

  14. Field emission electron source

    SciTech Connect

    Zettl, A.K.; Cohen, M.L.

    2000-05-02

    A novel field emitter material, field emission electron source, and commercially feasible fabrication method is described. The inventive field emission electron source produces reliable electron currents of up to 400 mA/cm{sup 2} at 200 volts. The emitter is robust and the current it produces is not sensitive to variability of vacuum or the distance between the emitter tip and the cathode. The novel emitter has a sharp turn-on near 100 volts.

  15. Source circuit design considerations

    NASA Astrophysics Data System (ADS)

    Noel, G. T.

    1983-11-01

    The cost of several circuit configurations for large (5MW) array fields were investigated to assess the relative costs of high and low voltage configurations. Three source circuit NOC voltages were evaluated: 400V (ungrounded), 800V (+ or 400V center grounded), and 2000V (+ or - 1000V center grounded). Four source circuit configurations were considered for each of the three NOC voltages. The configurations correspond to source circuit currents of 15, 30, 45, and 60 amperes, respectively. Conceptual layouts for 5MW building blocks for each of the above configurations were developed. The designs were optimized to minimize BOS electrical and structural costs. Only the BOS electrical costs were evaluated. The designs were broken down into the following elements for cost: (1) basic source circuit intermodule wiring, bypass diodes and associated hardware, source circuit to J-Box wiring, etc; (2) J-Box blocking diodes, varistors, heat sinks, and housing; (3) disconnects source circuit disconnects, fuses, and housing; (4) bus cabling J-Box to PCU interface wiring, and trenching; (5) interface bus bar, group disconnects, and fuses; and (6) fault detection shunts, signal wire, electronics, and alarm. It is concluded that high voltage low current circuits are not economical, at higher currents high and low voltage circuit costs approach each other, high voltage circuits are not likely to offer near term advantage, and development work/manufacturer stimulation is needed to develop low cost high voltage hardware.

  16. Source circuit design considerations

    NASA Technical Reports Server (NTRS)

    Noel, G. T.

    1983-01-01

    The cost of several circuit configurations for large (5MW) array fields were investigated to assess the relative costs of high and low voltage configurations. Three source circuit NOC voltages were evaluated: 400V (ungrounded), 800V (+ or 400V center grounded), and 2000V (+ or - 1000V center grounded). Four source circuit configurations were considered for each of the three NOC voltages. The configurations correspond to source circuit currents of 15, 30, 45, and 60 amperes, respectively. Conceptual layouts for 5MW building blocks for each of the above configurations were developed. The designs were optimized to minimize BOS electrical and structural costs. Only the BOS electrical costs were evaluated. The designs were broken down into the following elements for cost: (1) basic source circuit intermodule wiring, bypass diodes and associated hardware, source circuit to J-Box wiring, etc; (2) J-Box blocking diodes, varistors, heat sinks, and housing; (3) disconnects source circuit disconnects, fuses, and housing; (4) bus cabling J-Box to PCU interface wiring, and trenching; (5) interface bus bar, group disconnects, and fuses; and (6) fault detection shunts, signal wire, electronics, and alarm. It is concluded that high voltage low current circuits are not economical, at higher currents high and low voltage circuit costs approach each other, high voltage circuits are not likely to offer near term advantage, and development work/manufacturer stimulation is needed to develop low cost high voltage hardware.

  17. Radiation source search toolkit

    NASA Astrophysics Data System (ADS)

    Young, Jason S.

    The newly developed Radiation Source Search Toolkit (RSST) is a toolkit for generating gamma-ray spectroscopy data for use in the testing of source search algorithms. RSST is designed in a modular fashion to allow for ease of use while still maintaining accuracy in developing the output spectra. Users are allowed to define a real-world path for mobile radiation detectors to travel as well as radiation sources for possible detection. RSST can accept measured or simulated radiation spectrum data for generation into a source search simulation. RSST handles traversing the path, computing distance related attenuation, and generating the final output spectra. RSST also has the ability to simulate anisotropic shielding as well as traffic conditions that would impede a ground-based detection platform in a real-world scenario. RSST provides a novel fusion between spectral data and geospatial source search data generation. By utilizing the RSST, researchers can easily generate multiple datasets for testing detection algorithms without the need for actual radiation sources and mobile detector platforms.

  18. HIGH VOLTAGE ION SOURCE

    DOEpatents

    Luce, J.S.

    1960-04-19

    A device is described for providing a source of molecular ions having a large output current and with an accelerated energy of the order of 600 kv. Ions are produced in an ion source which is provided with a water-cooled source grid of metal to effect maximum recombination of atomic ions to molecular ions. A very high accelerating voltage is applied to withdraw and accelerate the molecular ions from the source, and means are provided for dumping the excess electrons at the lowest possible potentials. An accelerating grid is placed adjacent to the source grid and a slotted, grounded accelerating electrode is placed adjacent to the accelerating grid. A potential of about 35 kv is maintained between the source grid and accelerating grid, and a potential of about 600 kv is maintained between the accelerating grid and accelerating electrode. In order to keep at a minimum the large number of oscillating electrons which are created when such high voltages are employed in the vicinity of a strong magnetic field, a plurality of high voltage cascaded shields are employed with a conventional electron dumping system being employed between each shield so as to dump the electrons at the lowest possible potential rather than at 600 kv.

  19. Deep source gas

    SciTech Connect

    Not Available

    1985-02-01

    Three separate emplacement concepts could explain the occurrence of gas at extreme depths: abiogenesis (a primordial, nonbiologic origin source); subducted, organic-origin gas (involving the deep, tectonic subduction emplacement of hydrocarbon-generating ocean sediments); and deep sedimentary basin gas (the more conventional emplacement of sedimentary rocks by deep downwarping of the Earth's crust). Of these concepts, Deep Source Gas research focuses on the subducted, organic-origin concept. The purpose of Deep Source Gas research is to verify natural gas arising from depths in excess of 30,000 feet, to relate these occurrences to conceptual models, to define the limits of target areas, to quantify the resource, and to determine the significance of the gas to the nation's reserves. The research emphasizes an Earth science study (geology, geochemistry, and geophysics) of the Cordilleran Geologic Province of western North America. This area is considered a prospective source largely because of known and suspected plate tectonic structures and their youthful emplacement, which increase the likelihood of a timely entrapment of deep-source generated hydrocarbons. Detailed geochemical studies indicate that the deep-source-gas generating capacity of the Aleutian Trench area of southern Alaska is high. Furthermore, geophysical studies show that an apparent fossil subduction zone exists in western Washington. This zone appears to have very thick sedimentary rock units, the existence of which will be evaluated through a more detailed seismic study and possibly through drilling activities. Structural observations made in the northern Brooks Range and central Alaskan Range indicate that overthrusting and compressional features may serve as large-scale target areas for deep source gas generation and occurrence. 12 figures, 2 tables.

  20. Pulsed ion beam source

    DOEpatents

    Greenly, J.B.

    1997-08-12

    An improved pulsed ion beam source is disclosed having a new biasing circuit for the fast magnetic field. This circuit provides for an initial negative bias for the field created by the fast coils in the ion beam source which pre-ionize the gas in the source, ionize the gas and deliver the gas to the proper position in the accelerating gap between the anode and cathode assemblies in the ion beam source. The initial negative bias improves the interaction between the location of the nulls in the composite magnetic field in the ion beam source and the position of the gas for pre-ionization and ionization into the plasma as well as final positioning of the plasma in the accelerating gap. Improvements to the construction of the flux excluders in the anode assembly are also accomplished by fabricating them as layered structures with a high melting point, low conductivity material on the outsides with a high conductivity material in the center. 12 figs.

  1. Terahertz Schottky Multiplier Sources

    NASA Technical Reports Server (NTRS)

    Schlecht, Erich T.

    2007-01-01

    This viewgraph presentation reviews the multiplier source technologies and the status/Performance of THz multiplier sources. An example of a THz application is imaging radar. The presentation reviews areas of requirements for THz sources: (1) Figures of merit, (i.e., Frequency Terahertz for high resolution Bandwidth of at least 15 GHz for high range resolution Efficiency (i.e., minimize power supply requirements) (2) Output power: (i.e., Milliwatts below 800 GHz, 10s of microwatts above 1 THz, 1-2 microwatts near 2 THz (3) Mechanical--stability, compact, low mass (4) Environmental -- radiation, vibration, thermal. Several sources for 0.3 - 2 THz are reviewed: FIR lasers, quantum cascade lasers (QCL), backward-wave oscillator (BWO), and Multiplier sources. The current state of the art (SoA) is shown as Substrateless Technology. It also shows where the SoA is for devices beyond 1 THz. The presentation concludes by reviewing the options for future development, and 2 technology roadmaps

  2. Astrophysics Source Code Library

    NASA Astrophysics Data System (ADS)

    Allen, A.; DuPrie, K.; Berriman, B.; Hanisch, R. J.; Mink, J.; Teuben, P. J.

    2013-10-01

    The Astrophysics Source Code Library (ASCL), founded in 1999, is a free on-line registry for source codes of interest to astronomers and astrophysicists. The library is housed on the discussion forum for Astronomy Picture of the Day (APOD) and can be accessed at http://ascl.net. The ASCL has a comprehensive listing that covers a significant number of the astrophysics source codes used to generate results published in or submitted to refereed journals and continues to grow. The ASCL currently has entries for over 500 codes; its records are citable and are indexed by ADS. The editors of the ASCL and members of its Advisory Committee were on hand at a demonstration table in the ADASS poster room to present the ASCL, accept code submissions, show how the ASCL is starting to be used by the astrophysics community, and take questions on and suggestions for improving the resource.

  3. Nutrition information sources.

    PubMed

    Farrell, L

    1972-10-01

    Medical personnel and medical librarians may tend to think of nutrition in medical terms and to forget its interdisciplinary aspects. For this reason, it is desirable for medical librarians to become familiar with a variety of sources of information on the composition of foods, nutrient values, food additives, and food protection. Many of these are government publications from such agencies as the U.S. Department of Agriculture, the National Research Council, and the Food and Agriculture Organization. Less familiar sources include nutrition materials from state agricultural experiment stations and extension services and important data published in a wide range of scientific or agricultural journals, which may be located through Nutrition Abstracts and Reviews, Food Science and Technology Abstracts, and the Bibliography of Agriculture. Sources of current information on nutrition research in progress include the Department of Agriculture's Current Research Information System (CRIS) and selective listings from the Smith-sonian Information Exchange. PMID:4563540

  4. Dual source heat pump

    DOEpatents

    Ecker, Amir L.; Pietsch, Joseph A.

    1982-01-01

    What is disclosed is a heat pump apparatus for conditioning a fluid characterized by a fluid handler and path for circulating the fluid in heat exchange relationship with a refrigerant fluid; at least two refrigerant heat exchangers, one for effecting heat exchange with the fluid and a second for effecting heat exchange between refrigerant and a heat exchange fluid and the ambient air; a compressor for efficiently compressing the refrigerant; at least one throttling valve for throttling liquid refrigerant; a refrigerant circuit; refrigerant; a source of heat exchange fluid; heat exchange fluid circulating device and heat exchange fluid circuit for circulating the heat exchange fluid in heat exchange relationship with the refrigerant; and valves or switches for selecting the heat exchangers and direction of flow of the refrigerant therethrough for selecting a particular mode of operation. The heat exchange fluid provides energy for defrosting the second heat exchanger when operating in the air source mode and also provides a alternate source of heat.

  5. Sources of gravitational waves

    NASA Technical Reports Server (NTRS)

    Schutz, Bernard F.

    1989-01-01

    Sources of low frequency gravitational radiation are reviewed from an astrophysical point of view. Cosmological sources include the formation of massive black holes in galactic nuclei, the capture by such holes of neutron stars, the coalescence of orbiting pairs of giant black holes, and various means of producing a stochastic background of gravitational waves in the early universe. Sources local to our Galaxy include various kinds of close binaries and coalescing binaries. Gravitational wave astronomy can provide information that no other form of observing can supply; in particular, the positive identification of a cosmological background originating in the early universe would be an event as significant as was the detection of the cosmic microwave background.

  6. COASTING ARC ION SOURCE

    DOEpatents

    Foster, J.S. Jr.

    1957-09-10

    An improved ion source is described and in particular a source in which the ions are efficiently removed. The plasma is generated in a tubular amode structure by the oscillation of electrons in an axial magnetic field, as in the Phillips Ion Gage. The novel aspect of the source is the expansion of the plasma as it leaves the anode structure, so as to reduce the ion density at the axis of the anode and present a uniform area of plasma to an extraction grid. The structure utilized in the present patent to expand the plasma comprises flange members of high permeability at the exitgrid end of the amode to diverge the magnetic field adjacent the exit.

  7. Nutrition Information Sources

    PubMed Central

    Farrell, Lois

    1972-01-01

    Medical personnel and medical librarians may tend to think of nutrition in medical terms and to forget its interdisciplinary aspects. For this reason, it is desirable for medical librarians to become familiar with a variety of sources of information on the composition of foods, nutrient values, food additives, and food protection. Many of these are government publications from such agencies as the U.S. Department of Agriculture, the National Research Council, and the Food and Agriculture Organization. Less familiar sources include nutrition materials from state agricultural experiment stations and extension services and important data published in a wide range of scientific or agricultural journals, which may be located through Nutrition Abstracts and Reviews, Food Science and Technology Abstracts, and the Bibliography of Agriculture. Sources of current information on nutrition research in progress include the Department of Agriculture's Current Research Information System (CRIS) and selective listings from the Smith-sonian Information Exchange. PMID:4563540

  8. Interferometry for rotating sources

    NASA Astrophysics Data System (ADS)

    Velle, S.; Mehrabi Pari, S.; Csernai, L. P.

    2016-06-01

    The two particle interferometry method to determine the size of the emitting source after a heavy ion collision is extended. Following the extension of the method to spherical expansion dynamics, here we extend the method to rotating systems. It is shown that rotation of a cylindrically symmetric system leads to modifications, which can be perceived as spatial asymmetry by the "azimuthal HBT" method. We study an exact rotating and expanding solution of the fluid dynamical model of heavy ion reactions. We consider a source that is azimuthally symmetric in space around the axis of rotation, and discuss the features of the resulting two particle correlation function. This shows the azimuthal asymmetry arising from the rotation. We show that this asymmetry leads to results similar to those given by spatially asymmetric sources.

  9. MEMS Incandescent Light Source

    NASA Technical Reports Server (NTRS)

    Tuma, Margaret; King, Kevin; Kim, Lynn; Hansler, Richard; Jones, Eric; George, Thomas

    2001-01-01

    A MEMS-based, low-power, incandescent light source is being developed. This light source is fabricated using three bonded chips. The bottom chip consists of a reflector on Silicon, the middle chip contains a Tungsten filament bonded to silicon and the top layer is a transparent window. A 25-micrometer-thick spiral filament is fabricated in Tungsten using lithography and wet-etching. A proof-of-concept device has been fabricated and tested in a vacuum chamber. Results indicate that the filament is electrically heated to approximately 2650 K. The power required to drive the proof-of-concept spiral filament to incandescence is 1.25 W. The emitted optical power is expected to be approximately 1.0 W with the spectral peak at 1.1 microns. The micromachining techniques used to fabricate this light source can be applied to other MEMS devices.

  10. The Sources of Radio News.

    ERIC Educational Resources Information Center

    Whitney, D. Charles

    To examine the production of programing material in a radio newsroom, a study was undertaken of the sources presented to the newsroom, of sources within the sources, of sources actively sought by the news staff, of degrees of processing of news items, and of the sources comprising the news output. Information in each of these areas was collected…

  11. Femtosecond tunable light source

    NASA Astrophysics Data System (ADS)

    Miesak, Edward Jozef

    1999-09-01

    A practical source of continuously tunable coherent visible and infrared light would have an enormous impact on science, medicine and technology. While microwave and radio transmitters offer wide tunability at the ``turn of a knob,'' the best known source of coherent optical radiation, the laser, does not possess the same versatility. Dye lasers provide some degree of tunability, but many dyes are needed to cover even the visible region. Ti:sapphire lasers are tunable only over the red to near infra-red portion of the spectrum (about 65 0 nm to about 1.1μm). This presentation documents the development of a unique pulsed light source tunable across the visible and near infrared portion of the spectrum, a femtosecond optical parametric amplifier (OPA). Much work was expended in developing the system itself. But a great deal of work was also done in developing the support equipment (hardware and software) necessary to build as well as maintain and operate an OPA. Once completed, the system characteristics were measured and documented. Initially it possessed ``personality'' which had to be understood and removed as much as possible. In addition, the pump source for this OPA, a regenerative amplifier, is unique in that it uses Cr3+:LiSGaF as the gain medium. This regen was also characterized and compared to other more standard regenerative amplifiers. System verification was done by performing a standard experiment (Z-scan) on well known samples, several of which are well characterized at specific wavelengths (1.06 μm, 0.523 μm) in the nanosecond and picosecond regimes. The results were compared against previously published results. The OPA was also compared against another very similar system which became commercially available during the time of this research. The results were helpful in analyzing the light source(s) and data acquisition systems for areas that could be improved.

  12. Intense fusion neutron sources

    NASA Astrophysics Data System (ADS)

    Kuteev, B. V.; Goncharov, P. R.; Sergeev, V. Yu.; Khripunov, V. I.

    2010-04-01

    The review describes physical principles underlying efficient production of free neutrons, up-to-date possibilities and prospects of creating fission and fusion neutron sources with intensities of 1015-1021 neutrons/s, and schemes of production and application of neutrons in fusion-fission hybrid systems. The physical processes and parameters of high-temperature plasmas are considered at which optimal conditions for producing the largest number of fusion neutrons in systems with magnetic and inertial plasma confinement are achieved. The proposed plasma methods for neutron production are compared with other methods based on fusion reactions in nonplasma media, fission reactions, spallation, and muon catalysis. At present, intense neutron fluxes are mainly used in nanotechnology, biotechnology, material science, and military and fundamental research. In the near future (10-20 years), it will be possible to apply high-power neutron sources in fusion-fission hybrid systems for producing hydrogen, electric power, and technological heat, as well as for manufacturing synthetic nuclear fuel and closing the nuclear fuel cycle. Neutron sources with intensities approaching 1020 neutrons/s may radically change the structure of power industry and considerably influence the fundamental and applied science and innovation technologies. Along with utilizing the energy produced in fusion reactions, the achievement of such high neutron intensities may stimulate wide application of subcritical fast nuclear reactors controlled by neutron sources. Superpower neutron sources will allow one to solve many problems of neutron diagnostics, monitor nano-and biological objects, and carry out radiation testing and modification of volumetric properties of materials at the industrial level. Such sources will considerably (up to 100 times) improve the accuracy of neutron physics experiments and will provide a better understanding of the structure of matter, including that of the neutron itself.

  13. INEEL Source Water Assessment

    SciTech Connect

    Sehlke, Gerald

    2003-03-01

    The Idaho National Engineering and Environmental Laboratory (INEEL) covers approximately 890 mi2 and includes 12 public water systems that must be evaluated for Source water protection purposes under the Safe Drinking Water Act. Because of its size and location, six watersheds and five aquifers could potentially affect the INEEL’s drinking water sources. Based on a preliminary evaluation of the available information, it was determined that the Big Lost River, Birch Creek, and Little Lost River Watersheds and the eastern Snake River Plain Aquifer needed to be assessed. These watersheds were delineated using the United States Geologic Survey’s Hydrological Unit scheme. Well capture zones were originally estimated using the RESSQC module of the Environmental Protection Agency’s Well Head Protection Area model, and the initial modeling assumptions and results were checked by running several scenarios using Modflow modeling. After a technical review, the resulting capture zones were expanded to account for the uncertainties associated with changing groundwater flow directions, a thick vadose zone, and other data uncertainties. Finally, all well capture zones at a given facility were merged to a single wellhead protection area at each facility. A contaminant source inventory was conducted, and the results were integrated with the well capture zones, watershed and aquifer information, and facility information using geographic information system technology to complete the INEEL’s Source Water Assessment. Of the INEEL’s 12 public water systems, three systems rated as low susceptibility (EBR-I, Main Gate, and Gun Range), and the remainder rated as moderate susceptibility. No INEEL public water system rated as high susceptibility. We are using this information to develop a source water management plan from which we will subsequently implement an INEEL-wide source water management program. The results are a very robust set of wellhead protection areas that will

  14. OLED area illumination source

    DOEpatents

    Foust, Donald Franklin; Duggal, Anil Raj; Shiang, Joseph John; Nealon, William Francis; Bortscheller, Jacob Charles

    2008-03-25

    The present invention relates to an area illumination light source comprising a plurality of individual OLED panels. The individual OLED panels are configured in a physically modular fashion. Each OLED panel comprising a plurality of OLED devices. Each OLED panel comprises a first electrode and a second electrode such that the power being supplied to each individual OLED panel may be varied independently. A power supply unit capable of delivering varying levels of voltage simultaneously to the first and second electrodes of each of the individual OLED panels is also provided. The area illumination light source also comprises a mount within which the OLED panels are arrayed.

  15. FABRICATION OF NEUTRON SOURCES

    DOEpatents

    Birden, J.H.

    1959-04-21

    A method is presented for preparing a neutron source from polonium-210 and substances, such as beryllium and boron, characterized by emission of neutrons upon exposure to alpha particles from the polonium. According to the invention, a source is prepared by placing powdered beryllium and a platinum foil electroplated with polonium-2;.0 in a beryllium container. The container is sealed and then heated by induction to a temperature of 450 to 1100 deg C to volatilize the polonium off the foil into the powder. The heating step is terminated upon detection of a maximum in the neutron flux level.

  16. Ultrashort pulsed neutron source.

    PubMed

    Pomerantz, I; McCary, E; Meadows, A R; Arefiev, A; Bernstein, A C; Chester, C; Cortez, J; Donovan, M E; Dyer, G; Gaul, E W; Hamilton, D; Kuk, D; Lestrade, A C; Wang, C; Ditmire, T; Hegelich, B M

    2014-10-31

    We report on a novel compact laser-driven neutron source with an unprecedented short pulse duration (<50  ps) and high peak flux (>10(18)  n/cm(2)/s), an order of magnitude higher than any existing source. In our experiments, high-energy electron jets are generated from thin (<3  μm) plastic targets irradiated by a petawatt laser. These intense electron beams are employed to generate neutrons from a metal converter. Our method opens venues for enhancing neutron radiography contrast and for creating astrophysical conditions of heavy element synthesis in the laboratory. PMID:25396373

  17. Ultrashort Pulsed Neutron Source

    NASA Astrophysics Data System (ADS)

    Pomerantz, I.; McCary, E.; Meadows, A. R.; Arefiev, A.; Bernstein, A. C.; Chester, C.; Cortez, J.; Donovan, M. E.; Dyer, G.; Gaul, E. W.; Hamilton, D.; Kuk, D.; Lestrade, A. C.; Wang, C.; Ditmire, T.; Hegelich, B. M.

    2014-10-01

    We report on a novel compact laser-driven neutron source with an unprecedented short pulse duration (<50 ps ) and high peak flux (>1018 n /cm2/s ), an order of magnitude higher than any existing source. In our experiments, high-energy electron jets are generated from thin (<3 μ m ) plastic targets irradiated by a petawatt laser. These intense electron beams are employed to generate neutrons from a metal converter. Our method opens venues for enhancing neutron radiography contrast and for creating astrophysical conditions of heavy element synthesis in the laboratory.

  18. Radially uniform electron source

    NASA Technical Reports Server (NTRS)

    Mccomas, D.; Bame, S. J.

    1982-01-01

    A thermionic electron source capable of producing uniform count rates in a number of channel electron multipliers simultaneously was required for conditioning multipliers for an extended space mission. It was found that a straight tungsten filament in the center of a cylindrically symmetric geometry surrounded by an array of multipliers emits a radially asymmetric distribution of electrons that changes with time. A source was developed which successfully produces a time-independent radially uniform distribution of electrons by moving the filament out of the direct line of sight and replacing it with a centrally located electron 'cloud.'

  19. An independent hydrogen source

    SciTech Connect

    Kobzenko, G.F.; Chubenko, M.V.; Kobzenko, N.S.; Senkevich, A.I.; Shkola, A.A.

    1985-10-01

    Descriptions are given of the design and operation of an independent hydrogen source used in purifying and storing hydrogen. If LaNi/sub 5/ or TiFe is used as the sorbent, one can store about 500 liter of chemically bound hydrogen in a vessel of 0.9 liter. Molecular purification of the desorbed hydrogen is used. The IHS is a safe hydrogen source, since the hydrogen is trapped in the sorbent in the chemically bound state and in equilibrium with LaNi/sub 5/Hx at room temperature. If necessary, the IHS can serve as a compressor and provide higher hydrogen pressures. The device is compact and transportable.

  20. CALUTRON ION SOURCE

    DOEpatents

    Oppenheimer, F.

    1958-08-19

    The construction of an ion source is descrtbed wherein a uniform and elongated arc is established for employment in a calutron. The novel features of the . source include the positioning of a cathode at one end of an elongated extt slit of an arc chamber. and anode electrodes defintng the longitudinal margins of the exit opening. When the exit slit is orientated in a parallel relation to a magnetic field, the arc extends in the direction of the magnetic field along and between the anode electrodes, which are held at a positsve potential with respect to the cathode.

  1. ATLAS OF SOURCE EMISSION PARTICLES

    EPA Science Inventory

    An atlas of various source emission particles characterized by electron optical techniques has been compiled for use by air pollution investigators. The particles studied were emitted by mobile, stationary, and natural sources. Sources included automobiles, manufacturing operatio...

  2. SOLE SOURCE AQUIFER BOUNDARY DATA

    EPA Science Inventory

    There are 7 polygons representing 6 individual sole source aquifer boundaries and one streamflow source area in California, Arizona, and Nevada. Various efforts were combined to create the final product, which represents the Federal Register boundary description. Sole source aqu...

  3. Evaluating Open Source Portals

    ERIC Educational Resources Information Center

    Goh, Dion; Luyt, Brendan; Chua, Alton; Yee, See-Yong; Poh, Kia-Ngoh; Ng, How-Yeu

    2008-01-01

    Portals have become indispensable for organizations of all types trying to establish themselves on the Web. Unfortunately, there have only been a few evaluative studies of portal software and even fewer of open source portal software. This study aims to add to the available literature in this important area by proposing and testing a checklist for…

  4. Incoherent Light Sources

    NASA Astrophysics Data System (ADS)

    Bertram, Dietrich; Born, Matthias; Jüstel, Thomas

    Since the invention and industrialization of incandescent lamps at the end radiation of the 19th century electrical lighting has become a commodity in our daily life. Today, incoherent light sources are used for numerous application areas. Major improvements have been achieved over the past decades with respect to lamp efficiency (Fig. 10.1), lifetime and color properties.

  5. Incoherent Light Sources

    NASA Astrophysics Data System (ADS)

    Bertram, Dietrich; Born, Matthias; Jüstel, Thomas

    Since the invention and industrialization of incandescent lamps at the end of the 19th century electrical lighting has become a commodity in our daily life. Today, incoherent light sources are used for numerous application areas. Major improvements have been achieved over the past decades with respect to lamp efficiency Fig. 10.1, lifetime and color properties.

  6. Does Source Reduction Work?

    ERIC Educational Resources Information Center

    Allaway, David

    1992-01-01

    Suggests that quantification is essential to establish the cost-effectiveness of source reduction (SR). Presents case studies of monitoring methods for seven different kinds of SR efforts: (1) packaging changes, (2) SR businesses, (3) waste exchanges, (4) individual nonresidential efforts, (5) variable garbage rates, (6) yard waste reduction, and…

  7. Detecting Illicit Radioactive Sources

    SciTech Connect

    McDonald, Joseph C.; Coursey, Bert; Carter, Michael

    2004-11-01

    Specialized instruments have been developed to detect the presence of illicit radioactive sources that may be used by terrorists in radiation dispersal devices, so-called ''dirty bombs'' or improvised nuclear devices. This article discusses developments in devices to detect and measure radiation.

  8. Selective ion source

    DOEpatents

    Leung, Ka-Ngo

    1996-01-01

    A ion source is described wherein selected ions maybe extracted to the exclusion of unwanted ion species of higher ionization potential. Also described is a method of producing selected ions from a compound, such as P.sup.+ from PH.sub.3. The invention comprises a plasma chamber, an electron source, a means for introducing a gas to be ionized by electrons from the electron source, means for limiting electron energy from the electron source to a value between the ionization energy of the selected ion species and the greater ionization energy of an unwanted ion specie, and means for extracting the target ion specie from the plasma chamber. In one embodiment, the electrons are generated in a plasma cathode chamber immediately adjacent to the plasma chamber. A small extractor draws the electrons from the plasma cathode chamber into the relatively positive plasma chamber. The energy of the electrons extracted in this manner is easily controlled. The invention is particularly useful for doping silicon with P.sup.+, AS.sup.+, and B.sup.+ without the problematic presence of hydrogen, helium, water, or carbon oxide ions. Doped silicon is important for manufacture of semiconductors and semiconductor devices.

  9. Selective ion source

    DOEpatents

    Leung, K.N.

    1996-05-14

    A ion source is described wherein selected ions maybe extracted to the exclusion of unwanted ion species of higher ionization potential. Also described is a method of producing selected ions from a compound, such as P{sup +} from PH{sub 3}. The invention comprises a plasma chamber, an electron source, a means for introducing a gas to be ionized by electrons from the electron source, means for limiting electron energy from the electron source to a value between the ionization energy of the selected ion species and the greater ionization energy of an unwanted ion specie, and means for extracting the target ion specie from the plasma chamber. In one embodiment, the electrons are generated in a plasma cathode chamber immediately adjacent to the plasma chamber. A small extractor draws the electrons from the plasma cathode chamber into the relatively positive plasma chamber. The energy of the electrons extracted in this manner is easily controlled. The invention is particularly useful for doping silicon with P{sup +}, As{sup +}, and B{sup +} without the problematic presence of hydrogen, helium, water, or carbon oxide ions. Doped silicon is important for manufacture of semiconductors and semiconductor devices. 6 figs.

  10. Oceanography Information Sources 70.

    ERIC Educational Resources Information Center

    Vetter, Richard C.

    This booklet lists oceanography information sources in the first section under industries, laboratories and departments of oceanography, and other organizations which can provide free information and materials describing programs and activities. Publications listed in the second section include these educational materials: bibliographies, career…