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Design, modeling, and current interpretations of the H-19 and H-11 tracer tests at the WIPP site

Description: Site-characterization studies at the Waste Isolation Pilot Plant (WIPP) site in southeastern New Mexico, US identified ground-water flow in the Culebra Dolomite Member of the Rustler Formation as the most likely geologic pathway for radionuclide transport to the accessible environment in the event of a breach of the WIPP repository through inadvertent human intrusion. The results of recent tracer tests, as well as hydraulic tests, laboratory measurements, and re-examination of Culebra geology and stratigraphy, have led to a significant refinement of the conceptual model for transport in the Culebra. Tracer test results and geologic observations suggest that flow occurs within fractures, and to some extent within interparticle porosity and vugs connected by microfractures. Diffusion occurs within all connected porosity. Numerical simulations suggest that the data from the tracer tests cannot be simulated with heterogeneous single-porosity models; significant matrix diffusion appears to be required. The low permeability and lack of significant tracer recovery from tracers injected into the upper Culebra suggest that transport primarily occurs in the lower Culebra.
Date: December 31, 1996
Creator: Meigs, L.C.; Beauheim, R.L.; McCord, J.T.; Tsang, Y.W. & Haggerty, R.

Design modeling of the 100-J diode-pumped solid-state laser for Project Mercury

Description: We present the energy, propagation, and thermal modeling for a diode-pumped solid-state laser called Mercury being designed and built at LLNL using Yb:S-FAP [i.e., Yb{sup 3+}-doped Sr{sub 5}(PO{sub 4}){sub 3}F crystals] for the gain medium. This laser is intended to produce 100 J pulses at 1 to 10 ns at 10 Hz with an electrical efficiency of {approximately}10%. Our modeling indicates that the laser will be able to meet its performance goals.
Date: February 23, 1998
Creator: Orth, C., LLNL

Design modifications, fabrication and test of HFDB-03 racetrack magnet wound with pre-reacted Nb3Sn Rutherford cable

Description: A 10 T racetrack magnet (HFDB-03) wound with pre-reacted Nb{sub 3}Sn Rutherford cable has been fabricated and tested at Fermilab. This magnet is the third one in a proof-of-principle series for the use of the React-and-Wind technology in common-coil dipole magnets for future accelerators. It consists of two flat racetrack coils (28 turns each) separated by 5 mm. The maximum field on the coil, at the short sample limit of 16530 A, is 10 tesla. The cable has 41 strands with 0.7 mm diameter and the minimum bend radius in the magnet ends is 90 mm. The predecessor of this magnet (HFDB-02) reached 78% of the short sample limit at 7.7 T. The mechanical design was improved and the fabrication procedure was slightly modified in order to address possible causes of limitation. In this paper we present the mechanical design and analysis of HFDB-03, the modifications to the fabrication procedure and the test results.
Date: October 7, 2003
Creator: al., Giorgio Ambrosio et

Design Modifications for Increasing the BOM and EOM Power Output and Reducing the Size and Mass of RTG for the Pluto Mission

Description: A companion paper analyzed the effect on source modules for three specific fuel options, and compared the predicted power output with JPL's latest goals for the Pluto Fast Flyby (PFF) mission. The results showed that a 5-module RTG cannot fully meet JPL's goals with any of the available fuels; and that a 6-module RTG more than meets those goals with Russian fuel, almost meets them with U.S. (Cassini-type) fuel, but still falls far short of meeting them with the depleted fuel from the aged (1982) Galileo spare RTG. The inadequacy of the aged fuel was disappointing,because heat source modules made from it already exist, and their use in PFF could result in substantial cost savings. The present paper describes additional analyses which showed that a six-module RTG with the aged fuel can meet JPL's stipulated power margin with a relatively simple design modification, that a second design modification makes it possible to recover all of the mass and size penalty for going from five to six heat source modules, and that a third modification could raise the EOM power margin to 16%. There are four copies in the file. Cross Reference ESD Files FSC-ESD-217-94-531 (CID #8572)
Date: June 1, 1994
Creator: Schock, Alfred; Or, Chuen T & Kumar, Vasanth

Design Modifications for Increasing the BOm and EOM Power Output and Reducing the Size and Mass of RTG for the Pluto Mission

Description: Paper presented at the 29th IECEC in Monterey, CA in August 1994. A companion paper analyzed the effect on source modules for three specific fuel options, and compared the predicted power output with JPL's latest goals for the Pluto Fast Flyby (PFF) mission. The results showed that a 5-module RTG cannot fully meet JPL's goals with any of the available fuels; and that a 6-module RTG more than meets those goals with Russian fuel, almost meets them with U.S. (Cassini-type) fuel, but still falls far short of meeting them with the depleted fuel from the aged (1982) Galileo spare RTG. The inadequacy of the aged fuel was disappointing,because heat source modules made from it already exist, and their use in PFF could result in substantial cost savings. The present paper describes additional analyses which showed that a six-module RTG with the aged fuel can meet JPL's stipulated power margin with a relatively simple design modification, that a second design modification makes it possible to recover all of the mass and size penalty for going from five to six heat source modules, and that a third modification could raise the EOM power margin to 16%.
Date: August 1, 1994
Creator: Schock, Alfred; Or, Chuen T & Kumar, Vasanth

Design Modifications to the SRE during FY 1960

Description: Abstract: The means to prevent the recurrence of tetralin leakage into the SRE sodium systems are discussed. Included is a description of the redesign of system components to utilize alternate coolants such as nitrogen, air, and NaK.
Date: February 15, 1961
Creator: Deegan, G. E.; Dermer, M. D.; Flanagan, J. S.; Gower, G. C.; Hall, R. J.; Hinze, R. B. et al.

DESIGN MODIFICATIONS TO THE SRE DURING FY 1960

Description: The means used to prevent the recurrence of tetralin leakage into the SRE sodium systems are discussed. Included is a description of the redssign of system components to utilize alteraate coolants such as nitrogen, air, and NaK. The use of kerosene to replace tetralin, where double containment is provided, is discussed. The physical properties are compared, and kerosene is shown to be free of the undesirable characteristics of tetralin. The fuelelement cleaning systsm was redesigned for steam washing, followed by a water rinse and vacuum drying. Hydrogen gas evolved during washing is oxidized with copper oxide to eliminate the possibility of a hydrogen-oxygen explosion if air should accidentally enter the vent system. The fuel element was changed from a seven- to a five-rod cluster to provide additional clearance in the channel. Element hardware was modified to provide an orifice location which will permit more precise flow calculations; a redesigned hanger assembly which will minimize sodium holdup; and filter screene at the channel entrance to prevent in-cluster plugging. Diagnostic instrumentation was provided for the reactor to monitor: fission-product activity in the reactor cover gas; rapidly varying reactor parameters during a reactor scram; internnl and aheath fuel temperatures; and fuinctions being performed whioh wiIl indicate the mode of operation. The data wiIl provide additionul information to the reactor operator, as well as provide a more comprehereive coverage for reaotor analysis. (auth)
Date: February 15, 1961
Creator: Deegan, G.E.; Dermer, M.D.; Flanagan, J.S.; Gower, G.C.; Hall, R.J.; Hinze, R.B. et al.

Design Molecular Recognition Materials for Chiral Sensors, Separtations and Catalytic Materials

Description: The goal is the development of materials that are highly sensitive and selective for chid chemicals and biochemical (such as insecticides, herbicides, proteins, and nerve agents) to be used as sensors, catalysts and separations membranes. Molecular modeling methods are being used to tailor chiral molecular recognition sites with high affinity and selectivity for specified agents. The work focuses on both silicate and non-silicate materials modified with chirally-pure fictional groups for the catalysis or separations of enantiomerically-pure molecules. Surfactant and quaternary amine templating is being used to synthesize porous frameworks, containing mesopores of 30 to 100 angstroms. Computer molecukw modeling methods are being used in the design of these materials, especially in the chid surface- modi~ing agents. Molecular modeling is also being used to predict the catalytic and separations selectivities of the modified mesoporous materials. The ability to design and synthesize tailored asymmetric molecular recognition sites for sensor coatings allows a broader range of chemicals to be sensed with the desired high sensitivity and selectivity. Initial experiments target the selective sensing of small molecule gases and non-toxic model neural compounds. Further efforts will address designing sensors that greatly extend the variety of resolvable chemical species and forming a predictive, model-based method for developing advanced sensors.
Date: November 1, 1998
Creator: Jia, S.; Nenoff, T.M.; Provencio, P.; Qiu, Y.; Shelnutt, J.A.; Thoma, S.G. et al.

Design note of an air-cooled 2 ft x 2 ft x 10. 5 ft long muon spoiler

Description: This note describes the construction of a muon spoiler (magnetized steel assembly) with a cross section of 2 ft by 2 ft and a length of 10.5 ft. Two such spoilers are operated in series at an average field of about 15 kGauss, from one 100 ADC, 40 V power supply. The purpose of the spoilers is to prevent muons from easily escaping beyond the muon laboratory experimental area by bending them down so that they have to pass through more earth. The spoilers reduce the muon dose rate beyond the experimental area by about a factor of 15 to 20. These types of spoilers are not precision devices. They were inexpensive to build from scrap materials using rough flame cutting methods. It took about 14 days to fabricate them.
Date: January 6, 1988
Creator: Visser, A. & Pathiyil, J.

Design notes for the next generation persistent object manager for CAP

Description: The CAP query system software at Fermilab has several major components, including SQS (for managing the query), the retrieval system (for fetching auxiliary data), and the query software itself. The central query software in particular is essentially a modified version of the `ptool` product created at UIC (University of Illinois at Chicago) as part of the PASS project under Bob Grossman. The original UIC version was designed for use in a single-user non-distributed Unix environment. The Fermi modifications were an attempt to permit multi-user access to a data set distributed over a set of storage nodes. (The hardware is an IBM SP-x system - a cluster of AIX POWER2 nodes with an IBM-proprietary high speed switch interconnect). Since the implementation work of the Fermi-ized ptool, the CAP members have learned quite a bit about the nature of queries and where the current performance bottlenecks exist. This has lead them to design a persistent object manager that will overcome these problems. For backwards compatibility with ptool, the ptool persistent object API will largely be retained, but the implementation will be entirely different.
Date: May 1, 1995
Creator: Isely, M.; Fischler, M. & Galli, M.

DESIGN OF 2.4 GHZ CMOS DIRECT CONVERSION LNA AND MIXER COMBINATION FOR WIRLESS DATA LINK TRANSCEIVER.

Description: Three LNA and mixer combinations in 0.6{micro}m and 0.4{micro}m standard CMOS processes for direct-conversion receiver of 2.4GHz ISM band short-range wireless data-link applications are described in this paper. Taking low power dissipation as first consideration, these designs, employing differential common-source LNA and double balanced mixer architectures, achieve total conversion gain as high as 42.4dB, DSB noise figure as low as 9.5dB, output-referred IP3 as high as of 21.3dBm at about 4mA DC current consumption. This proves it is possible to apply standard CMOS process to implement receiver front-end with low power dissipation for this kind of application, but gain changeable LNA is needed to combat the dominant flicker noise of the mixer in order to achieve acceptable sensitivity and dynamic range at the same time.
Date: April 10, 2002
Creator: ZHAO, D. & OCONNOR, P.

Design of 2-4 GHz Equalizers for the Antiproton Accumulator Stacktail System

Description: The antiproton source at Fermilab requires storage of antiprotons during the production of antiprotons. A fundamental part of the storage process involves stochastic cooling, which requires that the frequency spectrum from the pickups has notches at the revolution frequency and harmonics of the revolution frequency of the antiprotons in the storage ring. A system has been developed for broadband notches but suffers from dispersion. The dispersion inhibits the cooling process and therefore an equalizer is required. The process for designing the equalizers is described and results shown.
Date: January 1, 1999
Creator: Deibele, C. & /Wisconsin U., Madison

Design of 9-meter carbon-fiberglass prototype blades : CX-100 and TX-100 : final project report.

Description: TPI Composites, Inc. (TPI), Global Energy Concepts, LLC (GEC), and MDZ Consulting (MDZ) have collaborated on a project to design, manufacture, and test prototype carbon-fiberglass hybrid wind turbine blades of 9-m length. The project, funded by Sandia National Laboratories, involves prototype blades in both conventional (unidirectional spar fibers running along the blade span) and ''adaptive'' (carbon fibers in off-axis orientation to achieve bend-twist-coupling) configurations. After manufacture, laboratory testing is being conducted to determine the static and fatigue strength of the prototypes, in conjunction with field testing to evaluate the performance under operational conditions.
Date: September 1, 2007
Creator: Berry, Derek (TPI Composites, Inc., Warren, RI)

Design of 10 GeV laser wakefield accelerator stages with shaped laser modes

Description: We present particle-in-cell simulations, using the VORPAL framework, of 10 GeV laser plasma wakefield accelerator stages. Scaling of the physical parameters with the plasma density allows us to perform these simulations at reasonable cost and to design high performance stages. In particular we show that, by choosing to operate in the quasi-linear regime, we can use higher order laser modes to tailor the focusing forces. This makes it possible to increase the matched electron beam radius and hence the total charge in the bunch while preserving the low bunch emittance required for applications.
Date: September 25, 2009
Creator: Cormier-Michel, Estelle; Esarey, E.; Geddes, C.G.R.; Geddes, C.G.R.; Leemans, W.P.; Bruhwiler, D.L. et al.

Design of 15 mm collars for SSC dipole magnets

Description: Ten 1-m long dipole magnets of the SSC design ''D'' cross section have been constructed and tested. In each model a collar type structure was used to contain and support the coil assembly at assembly and during operation at 4K. The collar structure must provide enough coil compression to minimize training and guarantee the coil cross section dimensions. Three types of collar designs were used. The behavior, measured and predicted, of two types of 15 mm stainless steel collars used on eight of the ten models is examined. The mechanical measurement of the 15 mm stainless steel collars used on eight 1-m dipole models are given. Observed behavior and preliminary design criteria are discussed. In order to better understand observed collar behavior and to evaluate new designs, finite element analysis of the collar designs was undertaken, and results are correlated with measured behavior. The behavior of alternate collar designs is predicted. 3 refs., 19 figs. (LEW)
Date: March 1, 1986
Creator: Peters, C.

Design of 57.5 MHz cw RFQ structure for the rare isotope accelerator facility.

Description: The Rare Isotope Accelerator (RIA) facility includes a driver linac for production of 400 kW CW heavy-ion beams. The initial acceleration of heavy-ions delivered from an ECR ion source can be effectively performed by a 57.5 MHz four-meter long RFQ. The principal specifications of the RFQ are: (1) formation of extremely low longitudinal emittance; (2) stable operation over a wide range of voltage for acceleration of various ion species needed for RIA operation; (3) simultaneous acceleration of two-charge states of uranium ions. CW operation of an accelerating structure leads to a number of requirements for the resonators such as high shunt impedance, efficient water cooling of all parts of the resonant cavity, mechanical stability together with precise alignment, reliable rf contacts, a stable operating mode and fine tuning of the resonant frequency during operation. To satisfy these requirements a new resonant structure has been developed. This paper discusses beam dynamics and electrodynamics design of the RFQ cavity, as well as, some aspects of the mechanical design of this low-frequency CW RFQ.
Date: January 29, 2002
Creator: Ostroumov, P. N.; Kolomiets, A. A.; Kashinsky, D. A.; Minaev, S. A.; Pershin, V. I.; Yaramishev, S. G. et al.

Design of 118 MHz twelfth harmonic cavity of APS PAR

Description: Two radio frequency (RF) cavities are needed in the Positron Accumulator Ring (PAR) of the Advanced Photon Source. One is for the first harmonic frequency at 9.8 MHz, and the other is for the twelfth harmonic frequency at 118 MHz. This note reports on the design of the 118 MHz RF cavity. Computer models are used to find the mode frequencies, impedances, Q-factors, and field distributions in the cavity. The computer codes MAFIA, URMEL, and URMEL-T are useful tools which model and simulate the resonance characteristics of a cavity. These codes employ the finite difference method to solve Maxwell`s equations. MAFIA is a three-dimensional problem solver and uses square patches to approximate the inner surface of a cavity. URMEL and URMEL-T are two-dimensional problem solvers and use rectangular and triangular meshes, respectively. URMEL-T and MAFIA can handle problems with arbitrary dielectric materials located inside the boundary. The cavity employs a circularly cylindrical ceramic window to limit the vacuum to the beam pipe. The ceramic window used in the modeling will have a wall thickness of 0.9 cm. This wall thickness is not negligible in determining the resonant frequencies of the cavity. In the following, results of two- and three-dimensional modeling of the cavities using the URMEL-T and MAFIA codes are reported.
Date: October 22, 1992
Creator: Kang, Y.W.; Kustom, R.L. & Bridges, J.F.