Developments in solid state detectors for personnel neutron dosimetry (open access)

Developments in solid state detectors for personnel neutron dosimetry

The personnel neutron exposure potential at the Lawrence Livermore National Laboratory is more diverse than at many other facilities, due to the wide range of neutron producing activities. Albedo energy response problems in the face of the diversity of sources, and a concern about possible photon interferences with the neutron albedo response, have prompted development of some additional dosimetry techniques to augment the personnel monitoring program. This work now consists of two programs - the dosimeter/spectrometer (DOSPEC) in which track etch detectors are added to the albedo badge to provide some energy evaluation and gamma insensitivity, and development of solid state thin film MOS detectors to provide a real time, gamma insensitive dosimeter.
Date: July 23, 1981
Creator: Griffith, R.V.; Davidson, K.J.; Miller, D.E. & Vindelov, K.E.
Object Type: Article
System: The UNT Digital Library
DART II documentation. Volume III. Appendices (open access)

DART II documentation. Volume III. Appendices

The DART II is a data acquisition system that can be used with air pollution monitoring equipment. This volume contains appendices that deal with the following topics: adjustment and calibration procedures (power supply adjustment procedure, ADC calibration procedure, analog multiplexer calibration procedure); mother board signature list; schematic diagrams; device specification sheets (microprocessor, asynchronous receiver/transmitter, analog-to-digital converter, arithmetic processing unit, 5-volt power supply, +- 15-volt power supply, 24-volt power supply, floppy disk formater/controller, random access static memory); ROM program listing; 6800 microprocessor instruction set, octal listing; and cable lists. (RR)
Date: May 23, 1979
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Materials considerations for the coupling of thermochemical hydrogen cycles to tandem mirror reactors (open access)

Materials considerations for the coupling of thermochemical hydrogen cycles to tandem mirror reactors

Candidate materials are discussed and initial choices made for the critical elements in a liquid Li-Na Cauldron Tandem Mirror blanket and the General Atomic Sulfur-Iodine Cycle for thermochemical hydrogen production. V and Ti alloys provide low neutron activation, good radiation damage resistance, and good chemical compatibility for the Cauldron design. Aluminide coated In-800H and siliconized SiC are materials choices for heat exchanger components in the thermochemical cycle interface.
Date: May 23, 1980
Creator: Krikorian, O.H.
Object Type: Article
System: The UNT Digital Library
Thermophysical properties of coal liquids. Final report. [300 to 600 K] (open access)

Thermophysical properties of coal liquids. Final report. [300 to 600 K]

Thermophysical properties for coal-solvent slurries were determined in the range 300 to 600 K, in some cases extending to 700 K. Density, viscosity, thermal conductivity, and enthalpy were determined. A recycle solvent from the Wilsonville SRC-I plant and a KY-9 coal were used. Rheology was studied with a reciprocating cylinder viscometer designed to operate at elevated pressure and temperature. Viscous properties were found to follow the Bingham plastic model. A high-viscosity peak in the range 500 to 600 K was characterized by very high values of yield stress. At other temperatures the slurries were nearly Newtonian. Time and temperature dependence of viscous behavior were studied. Densities were determined by high temperature pyknometer, thermal conductivities by the transient line-source technique, and enthalpies by drop calorimeter and by pressure DSC.
Date: April 23, 1982
Creator: Droege, J. W.; Stickford, G. H.; Longanbach, J. R.; Venkateswar, R. & Chauhan, S. P.
Object Type: Report
System: The UNT Digital Library
Focal spot size predictions for beam transport through a gas-filled reactor (open access)

Focal spot size predictions for beam transport through a gas-filled reactor

Results from calculations of focal spot size for beam transport through a gas-filled reactor are summarized. In the converging beam mode, we find an enlargement of the focal spot due to multiple scattering and zeroth order self-field effects. This enlargement can be minimized by maintaining small reactors together with a careful choice of the gaseous medium. The self-focused mode, on the other hand, is relatively insensitive to the reactor environment, but is critically dependent upon initial beam quality. This requirement on beam quality can be significantly eased by the injection of an electron beam of modest current from the opposite wall.
Date: January 23, 1980
Creator: Yu, S. S.; Lee, E. P. & Buchanan, H. L.
Object Type: Article
System: The UNT Digital Library
Electric utility application of wind energy conversion systems on the island of Oahu (open access)

Electric utility application of wind energy conversion systems on the island of Oahu

The objective of this study was to assess the potential for the application of Wind Energy Conversion Systems (a field of interconnected WTGs denoted in this report by the acronym WECS) in a specific utility contest to gain advance information concerning their economic feasibility; their optional problems; the criteria and procedures for site selection; environmental impacts; legal, social, and other problems; and the balance of cost and benefits from the point of view of the consumer and the utility. This study addresses the circumstances of the Hawaiian Electric Company operations onthe Island of Oahu.
Date: February 23, 1979
Creator: Lindley, C.A. & Melton, W.C.
Object Type: Report
System: The UNT Digital Library
Geothermal commercial power plant study. Monthly progress report, September 25-October 22, 1976 (open access)

Geothermal commercial power plant study. Monthly progress report, September 25-October 22, 1976

Efforts were concentrated on plant operating modes. The Heber plant, which was previously designed for consistant brine temperature, was reviewed and changes necessary to accomodate declining brine temperature were determined. Resultant required modifications to the computer code GEOTHM were made. The engineering, in terms of sketches and equipment lists, needed to support the capital cost estimate was determined. Attempts to use the computer program GEOTHM to develop the heat and mass balances for plants with declining geothermal fluid temperature disclosed that this code alone cannot be used for this purpose because it does not include turbine stage pressure-drop equations. It was determined that the most expedient method for obtaining the data needed for this study would be to develop a separate small computer program containing these turbine equations. With the assistance of a turbine consultant, the detailed methodology for the program was developed, and coding was started. (MHR)
Date: November 23, 1976
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Analysis of SBTF quadelliptical furnaces. [LMFBR] (open access)

Analysis of SBTF quadelliptical furnaces. [LMFBR]

A computer model was developed which predicts the axial temperature profile and heat flux at the outer surface of the test section of the Sodium Boiling Test Facility constructed by the Engineering Technology Division at ORNL. The model was in agreement with observed temperature profiles at furnace power levels representative of single phase, dual phase, and dry-out operations. A parametric study demonstrated the effect of sodium flow rate and surface emissivities on the predicted temperature profile. It was concluded that axial conduction in the Hastelloy tube and sodium must be incorporated into the model to improve accuracy.
Date: February 23, 1979
Creator: Anderson, F. E. & Schulz, R. B.
Object Type: Report
System: The UNT Digital Library
Computer circuit analysis of induced currents in the MFTF-B magnet system (open access)

Computer circuit analysis of induced currents in the MFTF-B magnet system

An analysis was made of the induced current behavior of the MFTF-B magnet system. Although the magnet system consists of 22 coils, because of its symmetry we considered only 11 coils in the analysis. Various combinations of the coils were dumped either singly or in groups, with the current behavior in all magnets calculated as a function of time after initiation of the dump.
Date: October 23, 1981
Creator: Magnuson, G.D. & Woods, E.L.
Object Type: Report
System: The UNT Digital Library
Applications of holographic interferometry to cryogenic ICF target characterization (open access)

Applications of holographic interferometry to cryogenic ICF target characterization

Uniformity of condensed layers of DT fuel in cryogenic ICF targets is a crucial parameter in their design. Measurements by classical interferometry lacks resolution to determine DT layer uniformity for targets with thick glass shells and/or thick ablative polymer coatings. We have developed holographic interferometry as an alternative tool for layer uniformity determination. This method is sensitive only to the fuel layer itself. We describe the technique and interference pattern analysis, and present preliminary results.
Date: September 23, 1981
Creator: Bernat, T. P.; Darling, D. H. & Sanchez, J. J.
Object Type: Article
System: The UNT Digital Library
NOVANET: communications network for a control system (open access)

NOVANET: communications network for a control system

NOVANET is a control system oriented fiber optic local area network that was designed to meet the unique and often conflicting requirements of the Nova laser control system which will begin operation in 1984. The computers and data acquisition devices that form the distributed control system for a large laser fusion research facility need reliable, high speed communications. Both control/status messages and experimental data must be handled. A subset of NOVANET is currently operating on the two beam Novette laser system.
Date: May 23, 1983
Creator: Hill, J.R.; Severyn, J.R. & VanArsdall, P.J.
Object Type: Article
System: The UNT Digital Library
Preparation and properties of SYNROC D containing simulated Savannah River Plant high-level defense waste (open access)

Preparation and properties of SYNROC D containing simulated Savannah River Plant high-level defense waste

We describe in detail the formulation and processing steps used to prepare all SYNROC D samples tested in the Comparative Leach Testing Program at the Savannah River Laboratory. We also discuss how the composition of the Savannah River Plant sludge influences the formulation and ultimate preparation of SYNROC D. Mechanical properties are reported in the categories of elastic constants, flexural and compressive strengths, and microhardness; thermal expansion and thermal conductivity results are presented. The thermal expansion data indicated the presence of significant residual strain and the possibility of an unidentified amorphous or glassy phase in the microstructure. We summarize the standardized (MCC) leaching results for both crushed Synroc and monoliths in deionized water, silicate water, and salt brine at 90/sup 0/C and 150/sup 0/C.
Date: July 23, 1981
Creator: Hoenig, C.; Rozsa, R.; Bazan, F.; Otto, R. & Grens, J.
Object Type: Report
System: The UNT Digital Library
Economic impact of an improved methanol catalyst. [Forecasting to 2000] (open access)

Economic impact of an improved methanol catalyst. [Forecasting to 2000]

The economic future of methanol is reviewed in light of its potential uses as a substitute for traditional hydrocarbon fuels and feedstocks as well as some evolving new uses. Methanol's future market position will depend strongly on its production cost in comparison with competitive products. One promising way to reduce the production cost is by use of an improved catalyst in the process by which methanol is obtained from the feedstock - which can be either natural gas or a similar product such as synthesis gas from coal gasification. To estimate the potential cost savings with an improved catalyst, we have based our analysis on a recent study which assumed use of synthesis gas from underground coal gasification as a feedstock for making methanol. The improved catalyst we studied was an actinide oxide whose features include high tolerance to sulfur and heat, and a yield of about 4 mol% methanol per pass with a 2/1 mixture of H/sub 2//CO. We calculated the effect of this catalyst on methanol production costs in a 12,000-bbl/day plant. The result was a saving of from 1 cent to 2.5 cent per gallon on the total methanol synthesis cost of 23 cents per gallon (i.e., …
Date: June 23, 1983
Creator: Grens, J.; Borg, I.; Stephens, D. & Colmenares, C.
Object Type: Report
System: The UNT Digital Library
Colorado State University Program for Developing, Testing, Evaluating and Optimizing Solar Heating and Cooling Systems (open access)

Colorado State University Program for Developing, Testing, Evaluating and Optimizing Solar Heating and Cooling Systems

The objective is to develop and test various integrated solar heating, cooling and domestic hot water systems, and to evaluate their performance. Systems composed of new, as well as previously tested, components are carefully integrated so that effects of new components on system performance can be clearly delineated. The SEAL-DOE program includes six tasks which have received funding for the 1991--92 fifteen-month period. These include: (1) a project employing isothermal operation of air and liquid solar space heating systems, (2) a project to build and test several generic solar water heaters, (3) a project that will evaluate advanced solar domestic hot water components and concepts and integrate them into solar domestic hot water systems, (4) a liquid desiccant cooling system development project, (5) a project that will perform system modeling and analysis work on solid desiccant cooling systems research, and (6) a management task. The objectives and progress in each task are described in this report.
Date: March 23, 1992
Creator: unknown
Object Type: Report
System: The UNT Digital Library
A computer modeling study of isotopically selective, laser photodissociation of OCS in cryogenic solutions (open access)

A computer modeling study of isotopically selective, laser photodissociation of OCS in cryogenic solutions

Computer model calculations are presented for enrichments of carbon, oxygen, and sulfur isotopes by two-step, IR/UV, laser photodissociation of OCS in rare gas liquid solutions. The model calculations are based on previously measured fundamental physical properties, including spectroscopic parameters of the IR absorption bands of OCS in cryogenic solution, UV photodissociation cross sections for specific vibrational levels of OCS, and rates for vibrational relaxation of OCS by cryogenic solvents. Results are presented for both pulsed and continuous wave laser sources. Photodissociation through both the 2{nu}{sub 2} and {nu}{sub 1} intermediate vibrational levels of OCS is investigated. The laser characteristics required to obtain optimum enrichments are determined by modeling the dependence of enrichment on laser wavelength and intensity, as well as pulse width and timing for pulsed sources. Optimum carbon and oxygen isotope enrichment factors of 9--14 are found for two-step photodissociation through the OCS(2{nu}{sub 2}) vibrational level, using pulsed CO{sub 2} and KrF excimer laser sources. Optimum sulfur isotope enrichment factors of 5--6 are found for photodissociation through the OCS({nu}{sub 1}) level, using a pulsed 12 {mu}m laser and a KrF excimer laser. The enrichments found for continuous wave laser sources are smaller than those for pulsed sources. 19 figs., …
Date: December 23, 1991
Creator: Zittel, P.F.
Object Type: Report
System: The UNT Digital Library
Adapting Existing Spatial Data Sets to New Uses: An Example from Energy Modeling (open access)

Adapting Existing Spatial Data Sets to New Uses: An Example from Energy Modeling

Energy modeling and analysis often relies on data collected for other purposes such as census counts, atmospheric and air quality observations, and economic projections. These data are available at various spatial and temporal scales, which may be different from those needed by the energy modeling community. If the translation from the original format to the format required by the energy researcher is incorrect, then resulting models can produce misleading conclusions. This is of increasing importance, because of the fine resolution data required by models for new alternative energy sources such as wind and distributed generation. This paper addresses the matter by applying spatial statistical techniques which improve the usefulness of spatial data sets (maps) that do not initially meet the spatial and/or temporal requirements of energy models. In particular, we focus on (1) aggregation and disaggregation of spatial data, (2) imputing missing data and (3) merging spatial data sets.
Date: June 23, 2006
Creator: Johanesson, G; Stewart, J S; Barr, C; Sabeff, L B; George, R; Heimiller, D et al.
Object Type: Article
System: The UNT Digital Library
Accurate labeling of the light-actinide O4,5 ionization edges (open access)

Accurate labeling of the light-actinide O4,5 ionization edges

In this short article the accurate labeling of the O4,5 edges of the light actinides is addressed. The O4 and O5 edges are both contained in what is termed the ''giant resonance'' and the smaller ''pre-peak'' that is observed is a consequence of first-order perturbation by the 5d spin-orbit interaction. Thus, the small prepeak in the actinide 5d {yields} 5f transition should not be labeled the O5 peak, but rather the {Delta}S=1 peak.
Date: August 23, 2006
Creator: Moore, K & der Laan, G v
Object Type: Article
System: The UNT Digital Library
A Virtual Reality Framework to Optimize Design, Operation and Refueling of GEN-IV Reactors. (open access)

A Virtual Reality Framework to Optimize Design, Operation and Refueling of GEN-IV Reactors.

many GEN-IV candidate designs are currently under investigation. Technical issues related to material, safety and economics are being addressed at research laboratories, industry and in academia. After safety, economic feasibility is likely to be the most important crterion in the success of GEN-IV design(s). Lessons learned from the designers and operators of GEN-II (and GEN-III) reactors must play a vital role in achieving both safety and economic feasibility goals.
Date: April 23, 2008
Creator: Rizwan-uddin; Karancevic, Nick; Markidis, Stefano; Dixon, Joel; Luo, Cheng & Reynolds, Jared
Object Type: Report
System: The UNT Digital Library
Beyond Boltzmann-Gibbs statistics: Maximum entropy hyperensemblesout-of-equilibrium (open access)

Beyond Boltzmann-Gibbs statistics: Maximum entropy hyperensemblesout-of-equilibrium

What is the best description that we can construct of athermodynamic system that is not in equilibrium, given only one, or afew, extra parameters over and above those needed for a description ofthe same system at equilibrium? Here, we argue the most appropriateadditional parameter is the non-equilibrium entropy of the system, andthat we should not attempt to estimate the probability distribution ofthe system, but rather the metaprobability (or hyperensemble) that thesystem is described by a particular probability distribution. The resultis an entropic distribution with two parameters, one a non-equilibriumtemperature, and the other a measure of distance from equilibrium. Thisdispersion parameter smoothly interpolates between certainty of acanonical distribution at equilibrium and great uncertainty as to theprobability distribution as we move away from equilibrium. We deducethat, in general, large, rare fluctuations become far more common as wemove away from equilibrium.
Date: February 23, 2006
Creator: Crooks, Gavin E.
Object Type: Article
System: The UNT Digital Library
DHS Student Report (open access)

DHS Student Report

Throughout this project I have been involved in every step of the protocol. After proper training, I was introduced to the necessary lab techniques for the project. From then on it has been my responsibility to perform the necessary tasks to identify and isolate the mutants. This includes carrying out a detailed protocol of mixing reagents, streaking and incubating plates, inoculating cultures and evaluating any results in order to guide my actions for the next antibiotic concentration level. Simultaneously, I have been running PCR and sequencing reactions on all mutants in order to obtain the genetic sequence of the genes of interest for comparison. Once I have the gene sequences of interest I am able, with the aid of a sequencing program (Sequencher 4.2.2), to analyze the sequences of the mutants against that of a wild type strain. This entails aligning the DNA sequences of a given gene for each of the mutants and locating any base changes from the wild types bacteria's genes. These polymorphisms allow me to identify the QRDR for that particular gene. Depending on whether the polymorphism occurred at a low antibiotic concentration level or high concentration level, we can evaluate whether that change is necessary …
Date: July 23, 2007
Creator: Wynne, Elizabeth K.
Object Type: Report
System: The UNT Digital Library
Multipole Shimming of Permanent Magnets Using Harmonic CorrectorRings (open access)

Multipole Shimming of Permanent Magnets Using Harmonic CorrectorRings

Shimming systems are required to provide sufficient fieldhomogeneity for high resolution NMR. In certain specialized applications,such as rotating-field NMR and portable (ex-situ) NMR, permanentmagnet-based shimming systems can provide considerable advantages. Wepresent a simple two-dimensional shimming method based on harmoniccorrector rings which can provide arbitrary multipole order shimmingcorrections. Results demonstrate, for example, that quadrupolar ordershimming improves the linewidth by up to and order of magnitude. Anadditional order of magnitude reduction is in principle achievable byultilizing this shimming method for z-gradient correction and higherorder xy gradients.
Date: October 23, 2006
Creator: Jachmann, Rebecca C.; Trease, David R.; Bouchard, Louis-S.; Sakellariou, Dimitris; Martin, Rachel W.; Schlueter, Ross D. et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the Semileptonic Decays B->D tau nu and B->D* tau nu (open access)

Measurement of the Semileptonic Decays B->D tau nu and B->D* tau nu

The authors present measurements of the semileptonic decays B{sup -} {yields} D{sup 0} {tau}{sup -} {bar {nu}}{sub {tau}}, B{sup -} {yields} D*{sup 0} {tau}{sup -}{bar {nu}}{sub {tau}}, {bar B}{sup 0} {yields} D{sup +} {tau}{sup -} {bar {nu}}{sub {tau}}, and {bar B}{sup 0} {yields} D*{sup +} {tau}{sup -}{bar {nu}}{sub {tau}}, which are sensitive to non-Standard Model amplitudes in certain scenarios. The data sample consists of 232 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider. They select events with a D or D* meson and a light lepton ({ell} = e or {mu}) recoiling against a fully reconstructed B meson. They perform a fit to the joint distribution of lepton momentum and missing mass squared to distinguish signal B {yields} D{sup (*)}{tau}{sup -} {bar {nu}}{sub {tau}} ({tau}{sup -} {yields} {ell}{sup -} {bar {nu}}{sub {ell}}{nu}{sub {tau}}) events from the backgrounds, predominantly B {yields} D{sup (*)} {ell}{sup -}{bar {nu}}{sub {ell}}. They measure the branching-fraction ratios R(D) {triple_bond} {Beta}(B {yields} D{tau}{sup -} {bar {nu}}{sub {tau}})/{Beta}(B {yields} D{ell}{sup -} {bar {nu}}{sub {ell}}) and R(D*) {triple_bond} {Beta}(B {yields} D*{tau}{sup -} {bar {nu}}{sub {tau}})/{Beta}(B {yields} D* {ell}{sup -} {bar {nu}}{sub {ell}}) and, from a combined fit …
Date: February 23, 2009
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Target life time of laser ion source for low charge state ion production (open access)

Target life time of laser ion source for low charge state ion production

Laser ion source (LIS) produces ions by irradiating pulsed high power laser shots onto the solid state target. For the low charge state ion production, laser spot diameter on the target can be over several millimeters using a high power laser such as Nd:YAG laser. In this case, a damage to the target surface is small while there is a visible crater in case of the best focused laser shot for high charge state ion production (laser spot diameter can be several tens of micrometers). So the need of target displacement after each laser shot to use fresh surface to stabilize plasma is not required for low charge state ion production. We tested target lifetime using Nd:YAG laser with 5 Hz repetition rate. Also target temperature and vacuum condition were recorded during experiment. The feasibility of a long time operation was verified.
Date: June 23, 2008
Creator: Kanesue,T.; Tamura, J. & Okamura, M.
Object Type: Article
System: The UNT Digital Library
Reactive Distillation for Esterification of Bio-based Organic Acids (open access)

Reactive Distillation for Esterification of Bio-based Organic Acids

The following is the final report of the three year research program to convert organic acids to their ethyl esters using reactive distillation. This report details the complete technical activities of research completed at Michigan State University for the period of October 1, 2003 to September 30, 2006, covering both reactive distillation research and development and the underlying thermodynamic and kinetic data required for successful and rigorous design of reactive distillation esterification processes. Specifically, this project has led to the development of economical, technically viable processes for ethyl lactate, triethyl citrate and diethyl succinate production, and on a larger scale has added to the overall body of knowledge on applying fermentation based organic acids as platform chemicals in the emerging biorefinery. Organic acid esters constitute an attractive class of biorenewable chemicals that are made from corn or other renewable biomass carbohydrate feedstocks and replace analogous petroleum-based compounds, thus lessening U.S. dependence on foreign petroleum and enhancing overall biorefinery viability through production of value-added chemicals in parallel with biofuels production. Further, many of these ester products are candidates for fuel (particularly biodiesel) components, and thus will serve dual roles as both industrial chemicals and fuel enhancers in the emerging bioeconomy. The …
Date: September 23, 2008
Creator: Fields, Nathan; Miller, Dennis J.; Asthana, Navinchandra S.; Kolah, Aspi K.; Vu, Dung & Lira, Carl T.
Object Type: Report
System: The UNT Digital Library