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1/m<sub>c</sub> Terms in lambda<sup>+</sup><sub>c</sub> Semileptonic Decays

Description: We use the heavy quark effective theory to investigate the form factors that describe the semileptonic decays lambda<sup>+</sup><sub>c</sub> -> lambda e<sup>+</sup> nu, to order 1/m<sub>c</sub>. We find that a total of four form factors are needed to this order, in contrast with two form factors to leading order, and six form factors in the most general case. We point out some relationships that arise among the general form factors.
Date: February 1, 1992
Creator: Roberts, Winston
Partner: UNT Libraries Government Documents Department
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A 2 to 4 nm high power FEL on the SLAC linac

Description: We report the results of preliminary studies of a 2 to 4 nm SASE FEL, using a photoinjector to produce the electron beam, and the SLAC linac to accelerate it to an energy up to 10 GeV. Longitudinal bunch compression is used to increases ten fold the peak current to 2.5 kA, while reducing the bunch length to the subpicosecond range. The saturated output power is in the multi-gigawatt range, producing about 10{sup 14} coherent photons within a bandwidth of about 0.2% rms, in a pulse of several millijoules. At 120Hz repetition rate the average power is about 1 W. The system is optimized for x-ray microscopy in the water window around 2 to 4 nm, and will permit imaging a biological sample in a single subpicosecond pulse.
Date: September 1, 1992
Creator: Pellegrini, C.; Rosenzweig, J.; Nuhn, H. D.; Pianetta, P.; Tatchyn, R.; Winick, H. et al.
Partner: UNT Libraries Government Documents Department
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3-D Field Computations for Accelerator Magnets Using Finite Element and Integral Codes

Description: Two dimensional (2-D) computation has been an accepted part of the design of accelerator magnets since the 1960's, but three-dimensional (3-D) computations are still not fully trusted. This paper describes the successes and limitations of 3-D computations, as applied to accelerator magnets for the Advanced Photon Source (APS) at Argonne National Laboratory (ANL). Both the finite element code TOSCA and the edge element volume integral code CORAL have been used in these computations. The ends of the dipole bending magnet for the injector synchrotron were designed using TOSCA; comparisons with measurements are described. Computation of other APS magnets are also described.
Date: 1992~
Creator: Turner, L. R.; Kim, S. H.; Kim, K. & Kettunen, L.
Partner: UNT Libraries Government Documents Department
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3-D field computations for accelerator magnets using finite element and integral codes

Description: Two dimensional (2-D) computation has been an accepted part of the design of accelerator magnets since the 1960`s, but three-dimensional (3-D) computations are still not fully trusted. This paper describes the successes and limitations of 3-D computations, as applied to accelerator magnets for the Advanced Photon Source (APS) at Argonne National Laboratory (ANL). Both the finite element code TOSCA and the edge element volume integral code CORAL have been used in these computations. The ends of the dipole bending magnet for the injector synchrotron were designed using TOSCA; comparisons with measurements are described. Computation of other APS magnets are also described.
Date: December 1, 1992
Creator: Turner, L. R.; Kim, S. H.; Kim, K. & Kettunen, L.
Partner: UNT Libraries Government Documents Department
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3-D numerical investigation of the mantle dynamics associated with the breakup of Pangea

Description: Three-dimensional finite element calculations in spherical geometry are performed to study the response of the mantle with platelike blocks at its surface to an initial condition corresponding to subduction along the margins of Pangea. The mantle is treated as an infinite Prandtl number Boussinesq fluid inside a spherical shell with isothermal, undeformable, free-slip boundaries. Nonsubducting rigid blocks to model continental lithosphere are included in the topmost layer of the computational mesh. At the beginning of the numerical experiments these blocks represent the present continents mapped to their approximate Pangean positions. Asymmetrical downwelling at the margins of these nonsubducting blocks results in a pattern of stresses that acts to pull the supercontinent apart. The calculations suggest that the breakup of Pangea and the subsequent global pattern of seafloor spreading was driven largely by the subduction at the Pangean margins.
Date: January 1, 1992
Creator: Baumgardner, J. R.
Partner: UNT Libraries Government Documents Department
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3-D numerical investigation of the mantle dynamics associated with the breakup of Pangea

Description: Three-dimensional finite element calculations in spherical geometry are performed to study the response of the mantle with platelike blocks at its surface to an initial condition corresponding to subduction along the margins of Pangea. The mantle is treated as an infinite Prandtl number Boussinesq fluid inside a spherical shell with isothermal, undeformable, free-slip boundaries. Nonsubducting rigid blocks to model continental lithosphere are included in the topmost layer of the computational mesh. At the beginning of the numerical experiments these blocks represent the present continents mapped to their approximate Pangean positions. Asymmetrical downwelling at the margins of these nonsubducting blocks results in a pattern of stresses that acts to pull the supercontinent apart. The calculations suggest that the breakup of Pangea and the subsequent global pattern of seafloor spreading was driven largely by the subduction at the Pangean margins.
Date: October 1, 1992
Creator: Baumgardner, J. R.
Partner: UNT Libraries Government Documents Department
open access

7-GeV Advanced Photon Source Instrumentation Initiative conceptual design report

Description: In this APS Instrumentation Initiative, 2.5-m-long and 5-m-long insertion-device x-ray sources will be built on 9 straight sections of the APS storage ring, and an additional 9 bending-magnet sources will also be put in use. The front ends for these 18 x-ray sources will be built to contain and safeguard access to these bright x-ray beams. In addition, funds will be provided to build state-of-the-art insertion-device beamlines to meet scientific and technological research demands well into the next century. This new initiative will also include four user laboratory modules and a special laboratory designed to meet the x-ray imaging research needs of the users. The Conceptual Design Report (CDR) for the APS Instrumentation Initiative describes the scope of all the above technical and conventional construction and provides a detailed cost and schedule for these activities. According to these plans, this new initiative begins in FY 1994 and ends in FY 1998. The document also describes the preconstruction R&D plans for the Instrumentation Initiative activities and provides the cost estimates for the required R&D.
Date: December 1992
Partner: UNT Libraries Government Documents Department
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7-GeV Advanced Photon Source Instrumentation Initiative. Conceptual Design Report

Description: In this APS Instrumentation Initiative, 2.5-m-long and 5-m-long insertion-device x-ray sources will be built on 9 straight sections of the APS storage ring, and an additional 9 bending-magnet sources will also be put in use. The front ends for these 18 x-ray sources will be built to contain and safeguard access to these bright x-ray beams. In addition, funds will be provided to build state-of-the-art insertion-device beamlines to meet scientific and technological research demands well into the next century. This new initiative will also include four user laboratory modules and a special laboratory designed to meet the x-ray imaging research needs of the users. The Conceptual Design Report (CDR) for the APS Instrumentation Initiative describes the scope of all the above technical and conventional construction and provides a detailed cost and schedule for these activities. According to these plans, this new initiative begins in FY 1994 and ends in FY 1998. The document also describes the preconstruction R & D plans for the Instrumentation Initiative activities and provides the cost estimates for the required R & D.
Date: October 1992
Creator: Argonne National Laboratory
Partner: UNT Libraries Government Documents Department
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7-GeV Advanced Photon Source Instrumentation Initiative conceptual design report

Description: In this APS Instrumentation Initiative, 2.5-m-long and 5-m-long insertion-device x-ray sources will be built on 9 straight sections of the APS storage ring, and an additional 9 bending-magnet sources will also be put in use. The front ends for these 18 x-ray sources will be built to contain and safeguard access to these bright x-ray beams. In addition, funds will be provided to build state-of-the-art insertion-device beamlines to meet scientific and technological research demands well into the next century. This new initiative will also include four user laboratory modules and a special laboratory designed to meet the x-ray imaging research needs of the users. The Conceptual Design Report (CDR) for the APS Instrumentation Initiative describes the scope of all the above technical and conventional construction and provides a detailed cost and schedule for these activities. According to these plans, this new initiative begins in FY 1994 and ends in FY 1998. The document also describes the preconstruction R D plans for the Instrumentation Initiative activities and provides the cost estimates for the required R D.
Date: December 1, 1992
Partner: UNT Libraries Government Documents Department
open access

9-{beta}-arabinofuranosyladenine preferentially sensitizes radioresistant squamous cell carcinoma cell lines to x-rays

Description: The effect of 9-{beta}-arabinofuranosyladenine (ara-A) on sensitivity to the deleterious effects of x-rays was studied in six squamous cell carcinoma cell lines. Three lines were relatively radioresistant, having D{sub 0} values of 2.31 to 2.89 Gy, and the other three lines were relatively radiosensitive, having D{sub 0} values of between 1.07 and 1.45 Gy. Ara-A (50 or 500 {mu}M) was added to cultures 30 min prior to irradiation and removed 30 min after irradiation, and sensitivity was measured in terms of cell survival. The radiosensitizing effect of ara-A was very dependent on the inherent radiosensitivity of the tumor cell line. Fifty micromolar concentrations of ara-A sensitized only the two most radioresistant lines, SCC-12B.2 and JSQ-3. Five hundred micromolar concentrations of ara-A sensitized the more sensitive cell lines, SQ-20B and SQ-9G, but failed to have any effect on the radiation response of the two most sensitive cell lines, SQ-38 and SCC-61. Concentrations of ara-A as low as 10 {mu}M were equally efficient in inhibiting DNA synthesis in all six cell lines. These results suggest that the target for the radiosensitizing effect of ara-A is probably related to the factor controlling the inherent radiosensitivity of human tumor cells. Therefore, ara-A might be useful in overcoming radiation resistance in vivo.
Date: June 1, 1992
Creator: Heaton, D.; Mustafi, R. & Schwartz, J. L.
Partner: UNT Libraries Government Documents Department
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The 17 keV neutrino and neutrino tagging

Description: P-788 at FNAL proposed to search for neutrino oscillations in a tagged neutrino line. A K{sub L} beam and the decay modes K{sub L} {yields} {pi}{mu}{nu}{sub {mu}} and K {sub L} {yields} {pi}e{nu}{sub e} provides the neutrino flux. An upstream tagging spectrometer then identifies the hadron and lepton and reconstructs the K{sub L} decay; the lepton identification will specifies the neutrino as {nu}{sub e} or {nu}{sub {mu}} and distinguishes {nu} from {bar {nu}} at the decay vertex. A neutrino detector modeled after an existing deep-inelastic scattering spectrometer (rates have been worked out for the CCFR apparatus) can be used to associate the K{sub L} with a neutrino interaction, measure the neutrino energy, and analyze outgoing muons. Monte Carlo studies show that 30K {nu}{sub e} and 20K {nu}{sub {mu}} could be obtained in two fixed target runs at the Tevatron.
Date: February 1, 1992
Creator: Bernstein, R.H.
Partner: UNT Libraries Government Documents Department
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The 17 keV neutrino and neutrino tagging

Description: P-788 at FNAL proposed to search for neutrino oscillations in a tagged neutrino line. A K{sub L} beam and the decay modes K{sub L} {yields} {pi}{mu}{nu}{sub {mu}} and K {sub L} {yields} {pi}e{nu}{sub e} provides the neutrino flux. An upstream tagging spectrometer then identifies the hadron and lepton and reconstructs the K{sub L} decay; the lepton identification will specifies the neutrino as {nu}{sub e} or {nu}{sub {mu}} and distinguishes {nu} from {bar {nu}} at the decay vertex. A neutrino detector modeled after an existing deep-inelastic scattering spectrometer (rates have been worked out for the CCFR apparatus) can be used to associate the K{sub L} with a neutrino interaction, measure the neutrino energy, and analyze outgoing muons. Monte Carlo studies show that 30K {nu}{sub e} and 20K {nu}{sub {mu}} could be obtained in two fixed target runs at the Tevatron.
Date: February 1, 1992
Creator: Bernstein, R. H.
Partner: UNT Libraries Government Documents Department
open access

A 50 mm bore superconducting dipole with a unique iron yoke structure

Description: A 50 mm bore superconducting dipole with a thin stainless steel collar and a close in elliptical iron yoke was designed in order to obtain a high transfer function SW low saturation effects on the multipoles, and a one meter model was built and tested. Training behavior of the first 1 m model, called D19, is presented at 4.3 K and 1.8 K. At 1.8 K it reached the record field of 10.06 T. The two layer cos [theta] winding uses 30 and 36 strand cables identical to the cables of the 50 mm bore SSC dipole and it has an operating field of 6.6 T at 4.35 K with a current of 5800 A. To evaluate behavior at high fields, the mechanical structure for the model was designed for 10 T. The thin collar itself provides only a minimum prestress of 10 MPa. and the full prestress of 70 MPa is given by the iron yoke. An aluminum spacer is used to control the gap size in the vertically split iron yoke. The tapered gap in the yoke is determined by the size of the Al spacer so that during cooldown there is no loss of coil prestress and the gap remains closed when the magnet is energized.
Date: August 1, 1992
Creator: Dell'Orco, D.; Caspi, S.; O'Neill, J.; Lietzke, A.; Scanlan, R.; Taylor, C. E. et al.
Partner: UNT Libraries Government Documents Department
open access

A 50 mm bore superconducting dipole with a unique iron yoke structure

Description: A 50 mm bore superconducting dipole with a thin stainless steel collar and a close in elliptical iron yoke was designed in order to obtain a high transfer function SW low saturation effects on the multipoles, and a one meter model was built and tested. Training behavior of the first 1 m model, called D19, is presented at 4.3 K and 1.8 K. At 1.8 K it reached the record field of 10.06 T. The two layer cos {theta} winding uses 30 and 36 strand cables identical to the cables of the 50 mm bore SSC dipole and it has an operating field of 6.6 T at 4.35 K with a current of 5800 A. To evaluate behavior at high fields, the mechanical structure for the model was designed for 10 T. The thin collar itself provides only a minimum prestress of 10 MPa. and the full prestress of 70 MPa is given by the iron yoke. An aluminum spacer is used to control the gap size in the vertically split iron yoke. The tapered gap in the yoke is determined by the size of the Al spacer so that during cooldown there is no loss of coil prestress and the gap remains closed when the magnet is energized.
Date: August 1, 1992
Creator: Dell`Orco, D.; Caspi, S.; O`Neill, J.; Lietzke, A.; Scanlan, R.; Taylor, C. E. et al.
Partner: UNT Libraries Government Documents Department

92-204

Description: The background of this painting consists of gradations of red, orange, pink and gray hues layered with lines created by many dots of paint. Overlayed are images of running dogs and small geometric shapes.
Date: 1992
Creator: Falsetta, Vincent
Partner: UNT College of Visual Arts + Design
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100 MeV laser accelerator demonstration and 1 GeV baseline design development. 1992 Annual report

Description: The acceleration of relativistic electrons using the inverse Cerenkov effect was first demonstrated at Stanford University in 1981. Later, Fontana and Pantell developed an improved configuration for the inverse Cerenkov acceleration (ICA) process. A radially polarized laser beam is focused by an axicon onto the e-beam traveling through a gas-filled interaction region. The light intersects the e-beam at the Cerenkov angle {theta}{sub c}, where {theta}{sub c} = cos{sup {minus}1}(1/n{beta}), n is the index of refraction of the gas, and {beta} is the ratio of the electron velocity to the speed of light. The goal of the present program is to demonstrate improved laser acceleration using the Fontana and Pantell configuration. The experiments will be performed on the Accelerator Test Facility (ATF) located at Brookhaven National Laboratory (BNL). This facility features a 50 MeV linac fed by a Nd:YAG (4{omega}) laser-driven photocathode e-gun. It will be upgraded to 65 MeV in the near future. The ATF also has a high peak power CO{sub 2} laser, which was developed for laser acceleration studies. The present ICA experiment was divided into two phases. Phase 1 was to examine certain experimental issues in preparation for Phase 2. Phase 1 was successfully completed in the spring of 1992. Phase 2 is to perform the actual laser acceleration experiments on the ATF e-beam. The authors are currently waiting for the availability of the e-beam so that they can begin the Phase 2 experiments. In this section, the theory and experimental hardware for the present program are described. The results of the Phase 1 experiments are presented, and an update on the Phase 2 experiment is given.
Date: December 1, 1992
Partner: UNT Libraries Government Documents Department
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101-SY Hydrogen Safety Project chemical analysis support: Window ``C`` total organic carbon analysis

Description: Core samples taken from Hanford double-shell waste tank 101-SY during Window ``C`` (after the May 1991 gas release event) were analyzed for total organic carbon by the staff of the Analytical Chemistry Laboratory at Pacific Northwest Laboratory. The procedure uses the oxidation/extraction method of hot acid persulfate oxidation. Evolved CO{sub 2} is measured by a UIC Coulometric Carbon Analyzer coulometry detector. Samples are acidified with heated sulfuric acid to drive off all inorganic carbonate carbon as CO{sub 2}. Excess potassium persulfate oxidant, along with a silver catalyst, is then added to the heated sulfuric acid solution. All organic carbon is oxidized to CO{sub 2}, swept away by the carrier gas to the Coulometrics Analyzer, and the results calculated and displayed directly as {mu}g carbon titrated.
Date: January 1, 1992
Creator: Gillespie, B. M.; Stromatt, R. W.; Baldwin, D. L. & Hoopes, F. V.
Partner: UNT Libraries Government Documents Department
open access

101-SY Hydrogen Safety Project chemical analysis support: Window C'' total organic carbon analysis

Description: Core samples taken from Hanford double-shell waste tank 101-SY during Window C'' (after the May 1991 gas release event) were analyzed for total organic carbon by the staff of the Analytical Chemistry Laboratory at Pacific Northwest Laboratory. The procedure uses the oxidation/extraction method of hot acid persulfate oxidation. Evolved CO{sub 2} is measured by a UIC Coulometric Carbon Analyzer coulometry detector. Samples are acidified with heated sulfuric acid to drive off all inorganic carbonate carbon as CO{sub 2}. Excess potassium persulfate oxidant, along with a silver catalyst, is then added to the heated sulfuric acid solution. All organic carbon is oxidized to CO{sub 2}, swept away by the carrier gas to the Coulometrics Analyzer, and the results calculated and displayed directly as {mu}g carbon titrated.
Date: January 1, 1992
Creator: Gillespie, B. M.; Stromatt, R. W.; Baldwin, D. L. & Hoopes, F. V.
Partner: UNT Libraries Government Documents Department
open access

The 400 MeV Linac Upgrade at Fermilab

Description: The Fermilab Linac Upgrade in planned to increase the energy of the H[sup [minus]] linac from 200 to 400 MeV. This is intended to reduce the incoherent space-charge tuneshift at injection into the 8 GeV Booster which limit either the brightness or the total intensity of the beam. The Linac Upgrade will be achieved by replacing the last four 201.25 MHs drift-tube linac (DTL) tanks which accelerate the beam from 116 to 200 MeV, with seven 805 MRs side-coupled cavity modules operating at an average axial field of about 7.5 MV/meter. This will allow acceleration to 400 MeV in the existing Linac enclosure. Each accelerator module will be driven with a 12 MW klystron-based rf power supply. Three of seven accelerator modules have been fabricated, power tested and installed in their temporary location adjacent to the existing DTL. All seven RF Modulators have been completed and klystron installation has begun. Waveguide runs have completed from the power supply gallery to the accelerator modules. The new linac will be powered in the temporary position without beam in order to verify overall system reliability until the laboratory operating schedule permits final conversion to 400 MeV operation.
Date: December 1, 1992
Creator: Noble, R.J.
Partner: UNT Libraries Government Documents Department
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The 400 MeV Linac Upgrade at Fermilab

Description: The Fermilab Linac Upgrade in planned to increase the energy of the H{sup {minus}} linac from 200 to 400 MeV. This is intended to reduce the incoherent space-charge tuneshift at injection into the 8 GeV Booster which limit either the brightness or the total intensity of the beam. The Linac Upgrade will be achieved by replacing the last four 201.25 MHs drift-tube linac (DTL) tanks which accelerate the beam from 116 to 200 MeV, with seven 805 MRs side-coupled cavity modules operating at an average axial field of about 7.5 MV/meter. This will allow acceleration to 400 MeV in the existing Linac enclosure. Each accelerator module will be driven with a 12 MW klystron-based rf power supply. Three of seven accelerator modules have been fabricated, power tested and installed in their temporary location adjacent to the existing DTL. All seven RF Modulators have been completed and klystron installation has begun. Waveguide runs have completed from the power supply gallery to the accelerator modules. The new linac will be powered in the temporary position without beam in order to verify overall system reliability until the laboratory operating schedule permits final conversion to 400 MeV operation.
Date: December 1992
Creator: Noble, Robert J.
Partner: UNT Libraries Government Documents Department
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500 MW demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NO[sub x]) emissions from coal-fired boilers

Description: The project provides a stepwise retrofit of an advanced overfire air (AOFA) system followed by low NO[sub x] burners (LNB). During each test phase of the project, diagnostic, performance, long-term, and verification testing will be performed. These tests are used to quantify the NO[sub x] reductions of each technology and evaluate the effects of those reductions on other combustion parameters such as particulatecharacteristics and boiler efficiency. Baseline, AOFA, and LNB without AOFA test segments have been completed. Analysis of the 94 days of LNB long-term data collected show the full-load NO[sub x] emission levels to be approximately 0.65 lb/MBtu. Flyash LOI values for the LNB configuration are approximately 8 percent at full-load. Corresponding values for the AOFA configuration are 0.94 lb/MBtu and approximately 10 percent. Abbreviated diagnostic tests for the LNB+AOFA configuration indicate that at 500 MWe, NO[sub x] emissions are approximately 0.55 lb/MBtu with corresponding flyash LOI values of approximately 11 percent. For comparison, the long-term full-load, baseline NO[sub x] emission level was approximately 1.24 lb/MBtu at 5.2 percent LOI. Comprehensive testing of the LNB+AOFA configuration will be performed when the stackparticulate emissions issue is resolved. Testing of a process optimization package on Plant Hammond Unit 4 was performed during this quarter. The software was configured to minimize NO[sub x] emissions using total combustion air flow and advanced overfire air distribution as the controlled parameters. Preliminary results from this testing indicate that this package shows promise in reducing NO[sub x] emissions while maintaining or improving other boiler performance parameters.
Date: January 1, 1992
Partner: UNT Libraries Government Documents Department
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500 MW demonstration of advanced wall-fired combustion techniques for the reduction of nitrogen oxide (NO{sub x}) emissions from coal-fired boilers. Third quarterly progress report, 1992: Innovative Clean Coal Technology (ICCT)

Description: The project provides a stepwise retrofit of an advanced overfire air (AOFA) system followed by low NO{sub x} burners (LNB). During each test phase of the project, diagnostic, performance, long-term, and verification testing will be performed. These tests are used to quantify the NO{sub x} reductions of each technology and evaluate the effects of those reductions on other combustion parameters such as particulatecharacteristics and boiler efficiency. Baseline, AOFA, and LNB without AOFA test segments have been completed. Analysis of the 94 days of LNB long-term data collected show the full-load NO{sub x} emission levels to be approximately 0.65 lb/MBtu. Flyash LOI values for the LNB configuration are approximately 8 percent at full-load. Corresponding values for the AOFA configuration are 0.94 lb/MBtu and approximately 10 percent. Abbreviated diagnostic tests for the LNB+AOFA configuration indicate that at 500 MWe, NO{sub x} emissions are approximately 0.55 lb/MBtu with corresponding flyash LOI values of approximately 11 percent. For comparison, the long-term full-load, baseline NO{sub x} emission level was approximately 1.24 lb/MBtu at 5.2 percent LOI. Comprehensive testing of the LNB+AOFA configuration will be performed when the stackparticulate emissions issue is resolved. Testing of a process optimization package on Plant Hammond Unit 4 was performed during this quarter. The software was configured to minimize NO{sub x} emissions using total combustion air flow and advanced overfire air distribution as the controlled parameters. Preliminary results from this testing indicate that this package shows promise in reducing NO{sub x} emissions while maintaining or improving other boiler performance parameters.
Date: December 31, 1992
Partner: UNT Libraries Government Documents Department
open access

600 kV modulator design for the SLAC Next Linear Collider Test Accelerator

Description: Preliminary design for the SLAC Next Linear Collider Test Accelerator (NLCTA) requires a pulse power source to produce a 600 kV, 600 A, 1.4 {mu}s, 0.1% flat top pulse with rise and fall times of approximately 100 ns to power an X-Band klystron with a microperveance of 1.25 at {approx} 100 MW peak RF power. The design goals for the modulator, including those previously listed, are peak modulator pulse power of 340 MW operating at 120 Hz. A three-stage darlington pulse-forming network, which produces a >100 kV, 1.4 {mu}s pulse, is coupled to the klystron load through a 6:1 pulse transformer. Careful consideration of the transformer leakage inductance, klystron capacitance, system layout, and component choice is necessary to produce the very fast rise and fall times at 600 kV operating continuously at 120 Hz.
Date: July 1, 1992
Creator: Harris, K.; de Lamare, J.; Nesterov, V. & Cassel, R.
Partner: UNT Libraries Government Documents Department
open access

600 kV modulator design for the SLAC Next Linear Collider Test Accelerator

Description: Preliminary design for the SLAC Next Linear Collider Test Accelerator (NLCTA) requires a pulse power source to produce a 600 kV, 600 A, 1.4 {mu}s, 0.1% flat top pulse with rise and fall times of approximately 100 ns to power an X-Band klystron with a microperveance of 1.25 at {approx} 100 MW peak RF power. The design goals for the modulator, including those previously listed, are peak modulator pulse power of 340 MW operating at 120 Hz. A three-stage darlington pulse-forming network, which produces a >100 kV, 1.4 {mu}s pulse, is coupled to the klystron load through a 6:1 pulse transformer. Careful consideration of the transformer leakage inductance, klystron capacitance, system layout, and component choice is necessary to produce the very fast rise and fall times at 600 kV operating continuously at 120 Hz.
Date: July 1, 1992
Creator: Harris, K.; de Lamare, J.; Nesterov, V. & Cassel, R.
Partner: UNT Libraries Government Documents Department
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