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Computerized system for ultralow temperature polarized nuclei time reversal and parity experiments

Description: From joint meeting of the American Nuclear Society and the Atomic Industrial Forum and Nuclear Energy Exhibition; San Francisco, California, USA (11 Nov 1973). A system used for data acquisition, control, and analysis in polarized radioactive nuclei experiments is described. Experimental precision requires data accumulation over long periods of time, and a computer is used for data reduction while the experiment is in progress. (auth)
Date: January 1, 1973
Creator: Handy, L.E. & Steyert, W.A.
Partner: UNT Libraries Government Documents Department

The phylogeny of Mediterranean tortoises and their close relativesbased on complete mitochondrial genome sequences from museumspecimens

Description: As part of an ongoing project to generate a mitochondrial database for terrestrial tortoises based on museum specimens, the complete mitochondrial genome sequences of 10 species and a {approx}14 kb sequence from an eleventh species are reported. The sampling of the present study emphasizes Mediterranean tortoises (genus Testudo and their close relatives). Our new sequences are aligned, along with those of two testudinoid turtles from GenBank, Chrysemys picta and Mauremys reevesii, yielding an alignment of 14,858 positions, of which 3,238 are parsimony informative. We develop a phylogenetic taxonomy for Testudo and related species based on well-supported, diagnosable clades. Several well-supported nodes are recovered, including the monophyly of a restricted Testudo, T. kleinmanni + T. marginata (the Chersus clade), and the placement of the enigmatic African pancake tortoise (Malacochersustornieri) within the predominantly Palearctic greater Testudo group (Testudona tax. nov.). Despite the large amount of sequence reported, there is low statistical support for some nodes within Testudona and Sowe do not propose names for those groups. A preliminary and conservative estimation of divergence times implies a late Miocene diversification for the testudonan clade (6-12 million years ago), matching their first appearance in the fossil record. The multi-continental distribution of testudonan turtles can be explained by the establishment of permanent connections between Europe, Africa, and Asia at this time. The arrival of testudonan turtles to Africa occurred after one or more initial tortoise invasions gave rise to the diverse (>25 species) 'Geochelone complex.'Two unusual genomic features are reported for the mtDNA of one tortoise, M. tornieri: (1) nad4 has a shift of reading frame that we suggest is resolved by translational frameshifting of the mRNA on the ribosome during protein synthesis and (2) there are two copies of the control region and trnF, with the latter having experienced multiple nucleotide substitutions in a ...
Date: April 29, 2005
Creator: Parham, James F.; Macey, J. Robert; Papenfuss, Theodore J.; Feldman, Chris R.; Turkozan, Oguz; Polymeni, Rosa et al.
Partner: UNT Libraries Government Documents Department

Development and testing of the ORNL/PLT neutral beam lines for the Princeton Large Torus

Description: Four neutral beam lines have been designed, constructed, and tested by the Oak Ridge National Laboratory (ORNL) in cooperation with the Princeton Plasma Physics Laboratory (PPPL) for application on the Princeton Large Torus (PLT) at PPPL. Two neutral beam lines are counterinjectors and two are coinjectors for a total neutral beam power of greater than 3 MW at 40 keV and up to 300 msec. Each beam line utilizes a 40-kV times 60-A modified duoPIGatron ion source with a close-coupled, 1.0-m long gas cell. Species ratios produced by the ion source are 84:13:3:E: E/2:E/3 for H/sup 0/ components delivered to the torus. The arc efficiency is less than 1 kW of arc power per ampere of beam current. Gas efficiency is approximately 50 percent with a total gas throughput of approximately 20 T-l/sec including supplemental gas to the gas cell. Two LHe cryocondensation pumps are used, one in the ion source tank with a speed of approximately 400,000 l/sec and the other in the drift tube with a speed of approximately 20,000 l/sec. The first beam line has been operated on PLT and has delivered 500 kW to the tokamak calorimeter for 150 msec. Initial heating results at 400 kW indicate an increase in T/sub i/, the central ion temperature, from 0.8 keV to approximately 1.5 keV.
Date: January 1, 1977
Creator: Dagenhart, W.K.; Gardner, W.L.; Haselton, H.H.; Menon, M.M.; Schechter, D.E.; Stirling, W.L. et al.
Partner: UNT Libraries Government Documents Department

Alignment and operability analysis of a vertical sodium pump

Description: With the objective of identifying important alignment features of pumps such as FFTF, HALLAM, EBR II, PNC, PHENIX, and CRBR, alignment of the vertical sodium pump for the Clinch River Breeder Reactor Plant (CRBRP) is investigated. The CRBRP pump includes a flexibly coupled pump shaft and motor shaft, two oil-film tilting-pad hydrodynamic radial bearings in the motor plus a vertical thrust bearing, and two sodium hydrostatic bearings straddling the double-suction centrifugal impeller in the pump.
Date: January 1, 1981
Creator: Gupta, V.K. & Fair, C.E.
Partner: UNT Libraries Government Documents Department

X-ray measurements of stresses and defects in EFG and large grained polycrystalline silicon ribbons

Description: The Bond method has been employed to measure the lattice parameter a in an area of 0.4 mm in diameter of EFG Si-ribbons to an accuracy of +- 0.00008 A. A Bond goniometer was built which included a goniostat with a special specimen holder to mount ribbons 1 m in length and 75 mm in width which could be rotated about two orthogonal axes, and a Leitz microscope for precision alignment of a particular area into the center of the goniostat and the small primary x-ray beam. The (321) planes were found to be parallel to the surface of the ribbons with an angular spread of about 15/sup 0/. The poles of the (111) planes clustered about an angle of 25/sup 0/ away from the surface normal, again with a spread of 10/sup 0/. The lattice parameter of a small piece of ribbon material was found to be a/sub 0/ = 5.43075 A. Converting the observed strain epsilon ( = (a-a/sub 0/)/a/sub 0/) into the sum of the principal surface stresses sigma/sub 1/ + sigma/sub 2/ assuming that the tilt angles of less than 15/sup 0/ can be neglected yielded values of sigma/sub 1/ + sigma/sub 2/ which were zero within the accuracy of our measurements of +- 10 MPa, but a maximum stress of 115 MPa was observed in a fractured ribbon which corresponded to the fracture stress of single crystals of Si.
Date: August 1, 1979
Creator: Wagner, C.N.J.
Partner: UNT Libraries Government Documents Department

Central Receiver Test Facility (CRTF) experiment manual

Description: The Central Receiver Test Facility is operated by Sandia Laboratories for the US Department of Energy. The CRTF is being used for component and subsystem evaluation within the Solar Thermal Large Power Systems Program. This experiment manual provides users of the CRTF detailed information about: (1) implementation of testing at the CRTF; (2) details of the CRTF capabilities and interfaces, and (3) requirements of experimenters.
Date: October 1, 1979
Creator: Holmes, J. T.; Matthews, L. K.; Seamons, L. O.; Davis, D. B. & King, D. L.
Partner: UNT Libraries Government Documents Department

Slicing of silicon into sheet material. Silicon sheet growth development for the large area silicon sheet task of the low cost silicon solar array project. Sixth quarterly report, June 18, 1977--September 18, 1977

Description: The ''Multiple Blade Alignment Device'' has been reported to JPL as a New Technology item, and is currently being reviewed for patent potential. The device has proven difficult to install on a blade package. Successful engagement of the device has resulted in an intrinsic parallelism of the ends of the package to within 3..mu.., compared to standard errors prior to correction of over 50..mu... Measurements of blade misalignment indicate an average runout of 50..mu.. in a 220 blade package. This compares well with predictions based on thickness variation measurements of blades and spacers. Early cutting tests with 0.15 mm blades and 10 cm diameter ingots show lower yield and accuracy and higher cutting speed than previous standard tests. This seems to be a result of effective high abrasive concentration on the blades as a result of the slurry application technique. A similar, more dramatic reduction of yield occurs with a thin slurry oil. This appears to occur by increased slurry transport to the blades and another effective increase of abrasive packing to the cutting region. Design of the large capacity MS saw is proceeding well, with a final conceptual design in progress. A flywheel system for work-piece drive is described. The design offers a practical conservative motion for the drive, requiring a minimum of power. 10 cm MS slices have been sent out for solar cell fabrication. 10 cm diameter and 2 cm square MS slices have been delivered for various surface preparations, and will be fabricated into cells and evaluated for performance. This will develop a minimum surface removal technique for both the damage and profiles peculiar to thin MS sices while allowing high efficiency cell production.
Date: September 30, 1977
Creator: Holden, S.C. & Fleming, J.R.
Partner: UNT Libraries Government Documents Department

Probing Interactions at the Nanoscale: Sensing Protein Molecules

Description: Introduction We have developed a high-frequency electronic biosensor of parallel-plate geometry that is embedded within a microfluidic device. This novel biosensor allows us to perform dielectric spectroscopy on a variety of biological samples—from cells to molecules—in solution. Because it is purely electronic, the sensor allows for rapid characterization with no sample preparation or chemical alteration. In addition, it is capable of probing length scales from millimeters to microns over a frequency range 50 MHz to 40 GHz, and sample volumes as small as picoliters [1,2]. Our high-frequency biosensor has evolved from previous device designs based on a coplanar waveguide (CPW) geometry [2]. For our current device, we employ microfluidic tectonics (µFT) [3] to embed two microstrip conductors within a microfluidic channel. The electronic coupling between the two conductors is greater than in our previous CPW design and more importantly, leads to an enhanced sensitivity. Our utilization of µFT allows us to incorporate easily this high-frequency electronic biosensor with a variety of lab-on-a-chip architectures. Device Description Figure 1 is a schematic of our high-frequency electronic biosensor. We fabricate this sensor by first depositing a 500 Å seed layer of gold onto two glass microscope slides. We then use photolithography to pattern the gold that is subsequently electroplated to a thickness of 4-6 µm. After reactive-ion etching the photoresist and removing the unplated gold with a standard iodine-based gold etchant, we align the two slides under a microscope such that the microstrip conductors overlap one another in a parallel-plate geometry (80 µm x 500 µm). We control the separation between the microstrip conductors using gold foil spacers 3–25 µm thick. The foil additionally ensures coupling between the grounds on each slide. Following alignment, we employ µFT to bond the two glass slides together and to create a microfluidic channel running perpendicular to ...
Date: September 15, 2003
Creator: Sohn, Lydia; Weiss, Ron & Tavazoie, Saeed
Partner: UNT Libraries Government Documents Department

Use of high index substrates to enable dislocation filtering in large mismatch systems

Description: We report results in three areas of research relevant to the fabrication of a wide range of optoelectronic devices: The development of a new x-ray diffraction technique that can be used to rapidly determine the optimal period of a strained layer superlattice to maximize the dislocation filtering; The optimal MBE growth parameters for the growth of CdTe on GaAs(211); The determination of the relative efficiency of dislocation filtering in the (211) and (100) orientations; and The surface quality of InSb grown by MOCVD on InSb substrates is affected by the misorientation of the substrate.
Date: January 1, 1997
Creator: Reno, J.L.; Biefeld, R.M.; Kurtz, S.R. & Baucom, K.C.
Partner: UNT Libraries Government Documents Department

Opto-mechanical design and fabrication services. Final report

Description: Each of the seven tasks defined under this contract are discussed here. They include: (1) design support for an x-ray spectrometer for the ``Panchuela`` down-hole experiment at the Nevada Test Site; (2) development and demonstration of an optical alignment method for aligning the 180 degree bend achromatic magnetic section of the Ground Test Accelerator; (3) development of magnet support and manipulation concepts for the 17 magnets of the Ground Test Accelerator; (4) design support for the triplett magnet telescope assembly and its support structure (Neutral Particle Beam Program); (5) design and support for the beam diagnostic system for the Argonne Particle Beam experiment; (6) conceptual design for the modification of an Antares Marx tank for use in the Aurora Laser Program; and (7) design of poloidal gap for the Los Alamos ZTH reversed-field pinch machine.
Date: February 28, 1988
Partner: UNT Libraries Government Documents Department

Electrical Transport Through a Single Nanoscale SemiconductorBranch Point

Description: Semiconductor tetrapods are three dimensional branched nanostructures, representing a new class of materials for electrical conduction. We employ the single electron transistor approach to investigate how charge carriers migrate through single nanoscale branch points of tetrapods. We find that carriers can delocalize across the branches or localize and hop between arms depending on their coupling strength. In addition, we demonstrate a new single-electron transistor operation scheme enabled by the multiple branched arms of a tetrapod: one arm can be used as a sensitive arm-gate to control the electrical transport through the whole system. Electrical transport through nanocrystals, molecules, nanowires and nanotubes display novel quantum phenomena. These can be studied using the single electron transistor approach to successively change the charge state by one, to reveal charging energies, electronic level spacings, and coupling between electronic, vibrational, and spin degrees of freedom. The advent of colloidal synthesis methods that produce branched nanostructures provides a new class of material which can act as conduits for electrical transport in hybrid organic-inorganic electrical devices such as light emitting diodes and solar cells. Already, the incorporation of branched nanostructures has yielded significant improvements in nanorod/polymer solar cells, where the specific pathways for charge migration can have a significant impact on device performance. Progress in this area requires an understanding of how electrons and holes migrate through individual branch points, for instance do charges delocalize across the branches or do they localize and hop between arms. Here we employ the single electron transistor approach to investigate the simplest three dimensional branched nanostructure, the semiconductor tetrapod, which consists of a pyramidal shaped zinc blende-structured ''core'' with four wurzite-structured arms projecting out at the tetrahedral angle. Monodisperse CdTe tetrapods with arms 8 nm in diameter and 150 nm in length were synthesized as previously reported. The tetrapods dispersed in ...
Date: June 9, 2005
Creator: Cui, Yi; Banin, Uri; Bjork, Mikael T. & Alivisatos, A. Paul
Partner: UNT Libraries Government Documents Department

The Rail Alignment Environmental Impact Statement: An Update

Description: On July 23,2002, the President of the United States signed into law a joint resolution of the United States Congress designating the Yucca Mountain site in Nye County, Nevada, for development as a geologic repository for the disposal of spent nuclear fuel and high-level radioactive waste. If the US. Nuclear Regulatory Commission authorizes construction of the repository and receipt and possession of spent nuclear fuel and high-level radioactive at Yucca Mountain, the U.S. Department of Energy (DOE) would be responsible for transporting these materials to the Yucca Mountain repository as part of its obligation under the Nuclear Waste Policy Act. Part of the site recommendation decision included the analysis of a nation-wide shipping campaign to the proposed repository site. The ''Final Environmental Impact Statement for a Geologic Repository for the Disposal of Spent Nuclear Fuel and High-Level Radioactive Waste at Yucca Mountain, Nye County, Nevada'' (February 2002) (Repository EIS) evaluated the potential impacts of the transportation of 70,000 Metric Tons of Heavy Metal spent nuclear fuel and high-level radioactive waste from 77 locations around the nation to the potential repository in Nevada over a 24 year shipping campaign. In the Repository EIS, DOE identified mostly rail as its preferred mode of transportation, both nationally and in the State of Nevada. In December 2003, based on public comments and the environmental analyses in the Repository EIS, DOE identified a preference for the Caliente rail corridor in Nevada. On April 8, 2004, DOE issued a Record of Decision (ROD) on the Mode of Transportation and Nevada Rail Corridor for the Disposal of Spent Nuclear Fuel and High-Level Radioactive Waste at Yucca Mountain, Nye County, Nevada. In this ROD, the DOE announced that it had decided to select the mostly rail scenario analyzed in the Repository EIS as the transportation mode both on ...
Date: January 20, 2005
Creator: Sweeney, R.
Partner: UNT Libraries Government Documents Department

Resonator design for a visible wavelength free-electron laser (*)

Description: Design requirements for a visible wavelength free-electron laser being developed at the Accelerator Test Facility at Brookhaven National Laboratory are presented along with predictions of laser performance from 3-D numerical simulations. The design and construction of the optical resonator, its alignment and control systems are also described. 15 refs., 8 figs., 4 tabs.
Date: January 1, 1990
Creator: Bhowmik, A.; Lordi, N. (Rockwell International Corp., Canoga Park, CA (United States). Rocketdyne Div.); Ben-Zvi, I. & Gallardo, J. (Brookhaven National Lab., Upton, NY (United States))
Partner: UNT Libraries Government Documents Department

Results of magnetic field measurements of 40 mm aperture 17-m long SSC model collider dipole magnets

Description: Magnetic field measurements have been made on twelve 17 m-long, 40 mm-aperture R D superconducting dipoles. Data on dipole field strength, multipole coefficients, and alignment have been obtained. The data indicate that the magnets as built are generally within the expectations for this design. 7 refs., 5 figs.
Date: January 1, 1991
Creator: Wanderer, P.; Anerella, M.; Cottingham, J.; Ganetis, G.; Garber, M.; Ghosh, A. et al.
Partner: UNT Libraries Government Documents Department

Status of the visible Free-Electron Laser at the Brookhaven Accelerator Test Facility

Description: The 500 nm Free-Electron Laser (ATF) of the Brookhaven National Laboratory is reviewed. We present an overview of the ATF, a high-brightness, 50-MeV, electron accelerator and laser complex which is a users' facility for accelerator and beam physics. A number of laser acceleration and FEL experiments are under construction at the ATF. The visible FEL experiment is based on a novel superferric 8.8 mm period undulator. The electron beam parameters, the undulator, the optical resonator, optical and electron beam diagnostics are discussed. The operational status of the experiment is presented. 22 refs., 7 figs.
Date: January 1, 1991
Creator: Batchelor, K.; Ben-Zvi, I.; Fernow, R.C.; Fisher, A.S.; Friedman, A.; Gallardo, J. et al.
Partner: UNT Libraries Government Documents Department

Oscilloscope trace photograph digitizing system (TRACE). [FAWTEK code]

Description: The digitizing system allows digitization of photographs or sketches of waveforms and then the computer is used to reduce and analyze the data. The software allows for alignment, calibration, removal of baselines, removal of unwanted points and addition of new points which makes for a fairly versatile system as far as data reduction and manipulation are concerned. System considerations are introduced first to orient the potential user to the process of digitizing information. The start up and actual commands for TRACE are discussed. Detailed descriptions of each subroutine and program section are also provided. Three general examples of typical photographs are included. A partial listing of FAWTEK is made available. Once suitable arrays that contain the data are arranged, ''GO FA'' (active FAWTEK) and many mathematical operations to further analyze the data may be performed.
Date: October 1, 1977
Creator: Richards, M. & Dabbs, R.D.
Partner: UNT Libraries Government Documents Department

Heavy Ion Fusion Accelerator Research (HIFAR)

Description: This report discusses the following topics: emittance variations in current-amplifying ion induction lina; transverse emittance studies of an induction accelerator of heavy ions; drift compression experiments on MBE-4 and related emittance; low emittance uniform- density C{sub s}+ sources for heavy ion fusion accelerator studies; survey of alignment of MBE-4; time-of-flight dependence on the MBE-4 quadrupole voltage; high order calculation of the multiple content of three dimensional electrostatic geometries; an induction linac injector for scaled experiments; induction accelerator test module for HIF; longitudinal instability in HIF beams; and analysis of resonant longitudinal instability in a heavy ion induction linac.
Date: April 1, 1991
Partner: UNT Libraries Government Documents Department

Calculation of magnetic error fields in hybrid insertion devices

Description: The Advanced Light Source (ALS) at the Lawrence Berkeley Laboratory requires insertion devices with fields sufficiently accurate to take advantage of the small emittance of the ALS electron beam. To maintain the spectral performance of the synchrotron radiation and to limit steering effects on the electron beam these errors must be smaller than 0.25%. This paper develops a procedure for calculating the steering error due to misalignment of the easy axis of the permanent magnet material. The procedure is based on a three dimensional theory of the design of hybrid insertion devices developed by one of us. The acceptable tolerance for easy axis misalignment is found for a 5 cm period undulator proposed for the ALS. 11 refs., 5 figs.
Date: August 1, 1989
Creator: Savoy, R.; Halbach, K.; Hassenzahl, W.; Hoyer, E.; Humphries, D. & Kincaid, B.
Partner: UNT Libraries Government Documents Department

Electron-beam sensitivity study of the Los Alamos Advanced Free-Electron Laser beam line

Description: A sensitivity study that used the particle tracking code PARMELA was performed on the Advanced Free-Electron Laser (AFEL). The tolerances on the alignment of the beam-line elements and the magnetic-field strengths were examined. Two base-line configurations were determined at the beginning of the study. The electron beam was then matched into the wiggler. The optimized beam-line parameters were varied independently and their sensitivities were judged with the criterion that the free-electron laser (FEL) effective-detuning parameter should not fluctuate more than 10%. The results of this study set the specifications for the alignment, for the sensitivity of the steering magnets, and for the accuracy of the magnetic field in the quadrupoles and dipoles. 5 figs., 3 figs., 3 tabs.
Date: January 1, 1991
Creator: Hartman, S. (California Univ., Los Angeles, CA (United States). Dept. of Physics); Lombardi, A.; Sheffield, R. & Wang, Tai-Sen (Los Alamos National Lab., NM (United States))
Partner: UNT Libraries Government Documents Department

J/. psi. and. Upsilon. production at CDF

Description: Characteristics of J/{psi} and {Upsilon} produced at the Tevatron and detected in the dimuon channel at CDF are reviewed. The masses of the J/{psi} and {Upsilon} are measured to be 3.096 {plus minus} 0.001 GeV/c{sup 2} and 9.469 {plus minus} 0.010 GeV/c{sup 2} respectively. These mass measurements are used to determine the systematic uncertainty on the momentum scale in the central tracking chamber. 2 refs., 14 figs.
Date: January 1, 1990
Creator: Liss, T. (Illinois Univ., Urbana, IL (USA))
Partner: UNT Libraries Government Documents Department

Assessment of magnetic field asymmetries in ELMO Bumpy Square

Description: There exist two separate and independent magnetic field asymmetries in the ELMO Bumpy Square (EBS). One is associated with the small perturbations in the magnetic field, known as the field errors, caused by coil misalignments during installation, imperfection in coil winding, etc. The second source of asymmetry is the magnetic field ripple in the high-field toroidal solenoids (corners) produced by the finiteness of the number of coils. In general, these two sources of asymmetry introduce enhanced transport losses (in addition to other effects) to the system, although they affect different classes of particles. Toroidally passing (circulating) particles (v/sub parallel//v approx. 1) are influenced by the field errors, whereas trapped particles (v/sub parallel//v approx. 0) in the corners are influenced by the field ripple. In this paper we discuss these two effects separately and calculate the allowable magnitudes of the field error and field ripple in EBS, both for an experimental-size device and for a reactor.
Date: January 1, 1985
Creator: Uckan, T. & Uckan, N.A.
Partner: UNT Libraries Government Documents Department

Measurements of magnetic field alignment

Description: The procedure for installing Superconducting Super Collider (SSC) dipoles in their respective cryostats involves aligning the average direction of their field with the vertical to an accuracy of 0.5 mrad. The equipment developed for carrying on these measurements is described and the measurements performed on the first few prototypes SSC magnets are presented. The field angle as a function of position in these 16.6 m long magnets is a characteristic of the individual magnet with possible feedback information to its manufacturing procedure. A comparison of this vertical alignment characteristic with a magnetic field intensity (by NMR) characteristic for one of the prototypes is also presented. 5 refs., 7 figs.
Date: November 6, 1987
Creator: Kuchnir, M. & Schmidt, E.E.
Partner: UNT Libraries Government Documents Department