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A compact proton linac for fast neutron cancer therapy (open access)

A compact proton linac for fast neutron cancer therapy

None
Date: January 1, 1999
Creator: Lennox, Arlene Judith; /Fermilab; Hamm, Robert W. & /AccSys Tech., Pleasanton
System: The UNT Digital Library
Tensor Analyzing Powers for Quasi-Elastic Electron Scattering from Deuterium (open access)

Tensor Analyzing Powers for Quasi-Elastic Electron Scattering from Deuterium

We report on a first measurement of tensor analyzing powers in quasi-elastic electron-deuteron scattering at an average three-momentum transfer of 1.7 fm{sup -1}. Data sensitive to the spin-dependent nucleon density in the deuteron were obtained for missing momenta up to 150 MeV/c with a tensor polarized {sup 2}H target internal to an electron storage ring. The data are well described by a calculation that includes the effects of final-state interaction, meson-exchange and isobar currents, and leading-order relativistic contributions.
Date: January 1, 1999
Creator: Zhou, Z.-L.; Bouwhuis, M.; Ferro-Luzzi, M.; Passchier, E.; Alarcon, R.; Anghinolfi, M. et al.
System: The UNT Digital Library
A flexible package and interconnects for microfluidic systems (open access)

A flexible package and interconnects for microfluidic systems

A slide-together compression package and microfluidic interconnects for microfabricated devices requiring fluidic and electrical connections is presented. The package assembles without tools, is reusable, and requires no epoxy, wirebonds, or solder, making chip replacement fast and easy. The microfluidic interconnects use standard HPLC PEEK tubing, with the tip machined to accept either an o-ring or custom molded ring which serves the dual function of forming the seal and providing mechanical retention strength. One design uses a screw to compress the o-ring, while others are simply plugged into a cartridge retained in the package. The connectors are helium leak-tight, can withstand hundreds of psi, are easy to connect and disconnect, are low dead volume, have a small footprint, and are adaptable to a broad range of microfabricated devices.
Date: January 1, 1999
Creator: Benett, W & Krulevitch, P
System: The UNT Digital Library
Design of a TEM waveguide for ultra-wideband applications (open access)

Design of a TEM waveguide for ultra-wideband applications

None
Date: January 1, 1999
Creator: Pao, H Y & Poggio, A
System: The UNT Digital Library
Establishing the Value of Advanced Glazings (open access)

Establishing the Value of Advanced Glazings

Numerous glazing technologies are under development worldwide to improve the performance of building facades. High-performance glazings can provide substantial energy and related environmental benefits, but often at greatly increased first cost when compared to conventional design solutions. To increase market viability, we discuss strategies to reduce the actual and owner-perceived costs associated with developing and producing advanced window systems, specifically switchable electrochromic glazings, and we also suggest marketing strategies designed to appeal to early adopter and mainstream purchasers. These strategies may be applicable to a broad range of advanced glazing materials.
Date: January 1, 1999
Creator: Lee, E & Selkowitz, S.
System: The UNT Digital Library
Bottom production asymmetries at the LHC (open access)

Bottom production asymmetries at the LHC

We present results on bottom hadron production asymmetries at the LHC within both the Lund string fragmentation model and the intrinsic bottom model. The main aspects of the models are summarized and specific predictions for pp collisions at 14 TeV are given. Asymmetries are found to be very small at central rapidities increasing to a few percent at forward rapidities. At very large rapidities intrinsic production could dominate but this region is probably out of reach of any experiment.
Date: January 1, 1999
Creator: Norrbin, E. & Vogt, R.
System: The UNT Digital Library
Instrumentation for biomedical and environmental applications based on microtechnology lessons learned (open access)

Instrumentation for biomedical and environmental applications based on microtechnology lessons learned

Over the last ten years, LLNL has been developing Microtechnology for instrumentation with applications in the biosciences and environment. In order to build and field high-performance instruments, they have often had to alter their original premises and assumptions, significantly. This meant that they were forced to abandon materials and dimensions that were appealing to them when they began the R and D. Examples include work on silicon-based electrophoresis systems, etched-fluidics for sample/sheath flow nozzles in flow cytometers, and polymerase-chain-reaction thermal-cycling chambers based on silicon-nitride. This presentation discusses these and their work on other devices and instruments.
Date: January 1, 1999
Creator: Mariella, Jr., R P
System: The UNT Digital Library
The effect of carbonate soil on transport and dose estimates for long-lived radionuclides at a U.S. Pacific test site (open access)

The effect of carbonate soil on transport and dose estimates for long-lived radionuclides at a U.S. Pacific test site

The US conducted a series of nuclear tests from 1946 to 1958 at Bikini, a coral atoll, in the Marshall Islands (MI). The aquatic and terrestrial environments of the atoll are still contaminated with several long-lived radionuclides that were generated during testing. The four major radionuclides found in terrestrial plants and soils are Cesium-137 ({sup 137}Cs), Strontium-90 ({sup 90}Sr), Plutonium-239+240 ({sup 239+240}Pu) and Americium-241 ({sup 241}Am). {sup 137}Cs in the coral soils is more available for uptake by plants than {sup 137}Cs associated with continental soils of North America or Europe. Soil-to-plant {sup 137}Cs median concentration ratios (CR) (kBq kg{sup {minus}1} dry weight plant/kBq kg{sup {minus}1} dry weight soil) for tropical fruits and vegetables range between 0.8 and 36, much larger than the range of 0.005 to 0.5 reported for vegetation in temperate zones. Conversely, {sup 90}Sr median CRs range from 0.006 to 1.0 at the atoll versus a range from 0.02 to 3.0 for continental silica-based soils. Thus, the relative uptake of {sup 137}Cs and {sup 90}Sr by plants in carbonate soils is reversed from that observed in silica-based soils. The CRs for {sup 239+240}Pu and {sup 241}Am are very similar to those observed in continental soils. Values range …
Date: January 1, 1999
Creator: Conrado, C L; Hamilton, T F; Robison, W L & Stoker, A C
System: The UNT Digital Library
Comparison of Analytical Methods: Direct Emission versus First-Derivative Fluorometric Methods for Quinine Determination in Tonic Waters (open access)

Comparison of Analytical Methods: Direct Emission versus First-Derivative Fluorometric Methods for Quinine Determination in Tonic Waters

Article on a comparison of analytical methods and a direct emission versus first-derivative fluorometric methods for quinine determination in tonic waters.
Date: January 1, 1999
Creator: Pandey, Siddharth; Borders, Tammie L.; Hernández, Carmen E.; Roy, Lindsay Elizabeth; Reddy, Gaddum D.; Martinez, Geo L. et al.
System: The UNT Digital Library
X-Ray Shawdowgraph Camera Design (open access)

X-Ray Shawdowgraph Camera Design

An imagining camera that is used with X-Ray radiography systems in high explosive experiments has been built and fielded. The camera uses a 40mm diameter Micro-Channel Plate Itensifier (MCPI) for optical gain and photographic film for image recording. In the normal location of the X-ray film pack, a scintillating screen is placed instead. The camera system views the screen and records the image. The sensitivity of the MCPI to light makes the camera design sensitive to small details that a film pack does not need to consider. The X-ray image recording system was designed and bulit for situations where the film pack of the X-ray shadowgraph is not retrievable after the experiment. The system has been used in a number of experiments.
Date: January 1, 1999
Creator: McCrea, Edward J.; Doman, Michael J. & Rohde, Randy A.
System: The UNT Digital Library
A microchannel electrophoresis DNA sequencing system (open access)

A microchannel electrophoresis DNA sequencing system

In order to increase the DNA sequencing throughput of the Joint Genome Institute, we have developed a microchannel electrophoresis system. The critical new and unique elements of this system include 1) a process for the production of arrays of 96 and 384 microchannels on bonded glass substrates up to 14 x 58 cm and 2) new sieving media for high resolution and high speed separations. With custom fabrication apparatus, microchannels are etched in a borosilicate substrate, and then fusion bonded to a top substrate 1.1 mm thick that has access holes formed in it. SEM examination shows a typical microchannel to be 40 micrometers deep x 180 micrometers wide by 46 cm long. This technology offers significant advantages over discrete capillaries or conventional slab-gel approaches. High throughput DNA sequencing with over 550 base pairs resolution has been achieved in roughly half the time of conventional sequencers. In February 1999, we begin a pre-production evaluation protocol for the microchannel and for three glass capillary electrophoresis systems (two from industry and one developed by Lawrence Berkeley National Laboratory for the Joint Genome Institute). In order to utilize these instruments for DNA production sequencing, we have been evaluating and implementing software to convert …
Date: January 1, 1999
Creator: Madabhushi, R. S.; Warth, T.; Balch, J. W.; Bass, M.; Brewer, L. R.; Copeland, A. C. et al.
System: The UNT Digital Library
Challenges and Potential Solutions for Reducing Climate Control Loads in Conventional and Hybrid Vehicles (open access)

Challenges and Potential Solutions for Reducing Climate Control Loads in Conventional and Hybrid Vehicles

The National Renewable Energy Laboratory, a U.S. Department of Energy national laboratory, is collaborating with U.S. automotive manufacturers to develop innovative techniques to reduce national fuel consumption and vehicle tailpipe emissions by reducing vehicle climate control loads. A new U.S. emissions test, the Supplemental Federal Test Procedure (SFTP), will soon begin measuring tailpipe emissions with the air conditioning system operating. Modeled results show that emissions of oxides of nitrogen (NOx) and carbon monoxide (CO) more than double during the air conditioning part of the SFTP. Reducing the transmittance of the glazing can have a greater impact on the cabin soak temperature than ventilating the vehicle during a hot soak. Reducing the amount of outside air can decrease cooling and heating loads but requires that the recirculated air be cleaned. We discuss a photocatalytic oxidation air-cleaning process for removing volatile organic compounds and bioareosols. We conclude with an example of modeling the thermal comfort of the occupants. An auxiliary load increase of only 400 Watts (W) results in a 0.4 km/L (1 mpg) decrease for a conventional 11.9-L/100-km (28-mpg) vehicle. If every vehicle in the United States were to save only 0.4 km/L (1 mpg), $4 billion (U.S. dollars) would be …
Date: January 1, 1999
Creator: Farrington, R.B., Anderson, R., Blake, D.M., Burch, S.D. & Cuddy, M.R., Keyser, M.A., Rugh, J.P.
System: The UNT Digital Library
Process Simulation as Applied to Transuranic Waste Management (open access)

Process Simulation as Applied to Transuranic Waste Management

The National Transuranic Waste System Model (the Model) is a computer simulation designed to evaluate the preparation and flow of TRU waste from generator sites throughout the Department of Energy (the Department) complex to the Waste Isolation Pilot Plant (WIPP) facility for disposal. The Model uses process simulation software to predict waste outputs of waste management operations as a function of time over the life of the WIPP. Process simulation modeling is a tool used by many industries, both private and public, to evaluate complex systems. For example a manufacturing plant might use process simulation to determine the possible effects of increasing the rate of production: will there be adequate resources (labor pool, raw goods, transportation capability); can the new production rate be sustained for an indefinite period of time without adding additional infrastructure. Process simulation modeling is also used by various military branches to ensure adequate supplies are delivered in a timely manner. The Department currently uses this technique as the basis for its National TRU Waste Management Plan Rev. 1 (DOE, 1997).
Date: January 1, 1999
Creator: Brown, M.; Downes, S. & Trone, J.
System: The UNT Digital Library
An Approach for Designing Thermal Management Systems for Electric and Hybrid Vehicle Battery Packs (open access)

An Approach for Designing Thermal Management Systems for Electric and Hybrid Vehicle Battery Packs

If battery packs for electric vehicles (EVs) and hybrid electric vehicles (HEVs) are to operate effectively in all climates, thermal management of the packs is essential. In this paper, we will review a systematic approach for designing and evaluating battery pack thermal management systems. A thermal management system using air as the heat transfer medium is less complicated than a system using liquid cooling/heating. Generally, for parallel HEVs, an air thermal management system is adequate, whereas for EVs and series HEVs, liquid-based systems may be required for optimum thermal performance. Further information on battery thermal management can be found on the Web site www.ctts.nrel.gov/BTM
Date: January 1, 1999
Creator: Pesaran, A.; Keyser, M. & Burch, S.
System: The UNT Digital Library
Top Quark Production and Decay Measurements from CDF (open access)

Top Quark Production and Decay Measurements from CDF

The CDF collaboration is completing a number of studies on the top quark, based on samples collected during Run I of the Tevatron Collider. The production and decay properties of the top quark are being examined in most of the t {anti t} decay channels, and many of these results have recently been published. The study of the top quark has moved beyond measurements of its mass and production cross section, to detailed studies of W polarization in top decays, single top production, branching fractions, the W - t - b coupling, and search for rare decays.
Date: January 1, 1999
Creator: Tollefson, K.
System: The UNT Digital Library
Enabling Field Spectroscopies (open access)

Enabling Field Spectroscopies

Environmental measurements are significantly enhanced by a complement of field-worthy spectrosopic instrumentation. These improvements can result in rapid turn around time, more representative sampling of larger areas, and lower overall costs. The qualities that make instrumentation field-worthy include real-time analysis, ruggedness, size/portability, analyte selectivity or specificity, detectability and, of course, sufficient accuracy and precision. The Characterization, Monitoring & Sensor Technology Crosscutting Program (CMST-CP) within the U.S. Department of Energy Environmental Management supports a wiede range of spectroscopic applications directly related to accelerating their cleanup efforts. Examples include tunable near infrared diode laser, laser-induced breakdown, imaging, beta, and mass spectroscopic technologies. Awarness of new technologies is crucial. An overview of these technologies will be presented.
Date: January 1, 1999
Creator: Weeks, Stephan J.
System: The UNT Digital Library
User`s information for the Monte Carlo burnup code monteburns (open access)

User`s information for the Monte Carlo burnup code monteburns

monteburns, a burnup computer code that uses the Monte Carlo technique, was developed at Los Alamos National Laboratory to be applied to a variety of nuclear design calculations (see accompanying paper on the development of monteburns). It is a fully automated burnup code that incorporates multiple irradiation steps and many other options. However, two of the most important aspects of developing a code are describing how to use it and benchmarking it. Thus, the operational aspects and benchmarking results from monteburns are discussed in this summary.
Date: January 1, 1999
Creator: Trellue, H.R. & Poston, D.I.
System: The UNT Digital Library
Importance of Deviatoric Stress in Modeling Void Growth in Ductile Fracture (open access)

Importance of Deviatoric Stress in Modeling Void Growth in Ductile Fracture

In this paper, the authors extend an upper bound result of Cocks [1989] to obtain a formula for porosity growth in ductile metals. Pressure and deviatoric stress are included. The matrix plasticity model involves the plastic strain rate as a power of the deviatoric stress, with a yield stress. The results show that the deviatoric stress cannot be neglected in calculating the porosity growth, even for high triaxialities.
Date: January 1, 1999
Creator: Tonks, D.L.; Zurek, A.K.; Thissell, W.R.; Rivera, J.M. & Hixson, R.S.
System: The UNT Digital Library
Operational Optimization of Large-Scale SRF Accelerators (open access)

Operational Optimization of Large-Scale SRF Accelerators

Unlike other types of accelerator subsystems, because of the flexibility in setting the gradient in each cavity, an SRF linac has many operational degrees of freedom. The overall linac has an operational envelope (beam voltage and current) that depends on acceptable reliability, cryogenic capacity, and RF power budget. For economic and end-user physics reasons, one typically wants to run as close to the edge of the operational envelope as possible. With about 160 cavities in each of the CEBAF linacs, we have been forced to treat this problem in a very general way, and satisfy other non-fundamental needs as energy lock and rapid recovery from failures. We present a description of the relevant diverse constraints and the solution developed for CEBAF.
Date: January 1, 1999
Creator: Delayen, J. R.; Doolittle, L. R. & Reece, C. E.
System: The UNT Digital Library
Beyond the adiabatic approximation: The impact of thresholds on the hadronic spectrum (open access)

Beyond the adiabatic approximation: The impact of thresholds on the hadronic spectrum

In the adiabatic approximation, most of the effects of quark-antiquark loops on spectroscopy can be absorbed into a static interquark potential. The author develops a formalism which can be used to treat the residual nonadiabatic effects associated with the presence of nearby hadronic thresholds for heavy quarks. He then defines a potential which includes additional high energy corrections to the adiabatic limit which would be present for finite quark masses. This improved potential allows a systematic low energy expansion of the impact of thresholds on hadronic spectra.
Date: January 1, 1999
Creator: Isgur, N.
System: The UNT Digital Library
Strangeness in the Nucleon or the quark model beyond the valence approximation (open access)

Strangeness in the Nucleon or the quark model beyond the valence approximation

Simple arguments based on unitarity indicate that meson loops diagrams, induced by an underlying qq pair creation process, should badly disturb the phenomenologically successful spectroscopy and dynamics of the valence quark model, including such simple but mysterious regularities as the OZI rule. The author discusses some recent progress in adding pair creation to the valence quark model in a way which provides rationale for the quark model's success.
Date: January 1, 1999
Creator: Isgur, Nathan
System: The UNT Digital Library
Thermoacoustic Engines and Refrigerators: A Short Course (open access)

Thermoacoustic Engines and Refrigerators: A Short Course

None
Date: January 1, 1999
Creator: Swift, G.W.
System: The UNT Digital Library
Aspen Winter Conference Series (open access)

Aspen Winter Conference Series

(B204) The meeting will bring together observers and theorists in a highly interactive format, to further connect the local and cosmological star formation communities. Forward looking talks, aimed at the other communities, will survey terminology, achievements, problems and aspirations. Discussion will focus on the definition of the key questions, how the different communities can help each other, and preparations for the incorporation of realistic star formation into cosmological simulations.
Date: January 1, 1999
Creator: unknown
System: The UNT Digital Library
The Goldberger-Treiman Discrepancy in SU(3) (open access)

The Goldberger-Treiman Discrepancy in SU(3)

The Goldberger-Treiman discrepancy in SU(3) is analyzed in the framework of heavy baryon chiral perturbation theory (HBChPT). It is shown that the discrepancy at leading order is entirely given by counterterms from the order p{sup 3} Lagrangian, and that the first subleading corrections are suppressed by two powers in the HBChPT expansion. These subleading corrections include meson-loop contributions as well as counterterms from the order p{sup 5} Lagrangian. Some one-loop contributions are calculated and found to be small. Using the three discrepancies ({pi}NN, KN{Lambda} and KN{Sigma}) which can be extracted from existing experimental data, the authors find that the HBChPT calculation favors the smaller g({pi}NN) values obtained in recent partial wave analyses.
Date: January 1, 1999
Creator: Goity, J. L.; Lewis, R.; Schvellinger, M. & Zhang, L.
System: The UNT Digital Library