Ultrasonic off-normal imaging techniques for under sodium viewing. [LMFBR] (open access)

Ultrasonic off-normal imaging techniques for under sodium viewing. [LMFBR]

Advanced imaging methods have been evaluated for the purpose of constructing images of objects from ultrasonic data. Feasibility of imaging surfaces which are off-normal to the sound beam has been established. Laboratory results are presented which show a complete image of a typical core component. Using the previous system developed for under sodium viewing (USV), only normal surfaces of this object could be imaged. Using advanced methods, surfaces up to 60 degrees off-normal have been imaged. Details of equipment and procedures used for this image construction are described. Additional work on high temperature transducers, electronics, and signal analysis is required in order to adapt the off-normal viewing process described here to an eventual USV application.
Date: December 6, 1979
Creator: Michaels, T.E. & Horn, J.E.
Object Type: Article
System: The UNT Digital Library
Alternating gradient synchrotron (open access)

Alternating gradient synchrotron

With the start of a research and development effort directed towards the Superconducting Super Collider (SSC), it is essential that US industry become involved as soon as possible. For that reason, I describe what a conventional accelerator complex is like and therefore what the first stages of the SSC would entail.
Date: December 6, 1984
Creator: Lowenstein, D.I.
Object Type: Article
System: The UNT Digital Library
Processing of poly-Si electrodes for charge-coupled devices (open access)

Processing of poly-Si electrodes for charge-coupled devices

A technique has been developed to fabricate poly-Si electrodes for charge-coupled devices. By controlling the microstructure of a poly-Si film, an anisotropic etchant was selected to provide essentially uniform electrode width dimensions. The electrode widths have only a 6% variation for the majority of the devices over the area of a 2 inch silicon wafer.
Date: December 6, 1978
Creator: Sherohman, J.W. & Cook, F.D.
Object Type: Report
System: The UNT Digital Library
Diffusive transport enhancement by isolated resonances and distribution tails growth in hadronic beams (open access)

Diffusive transport enhancement by isolated resonances and distribution tails growth in hadronic beams

The escape rates and evolution of a distribution of particles are considered for a 2-D model of transverse motion of particles in hadronic storage rings, when nonlinear resonances and external diffusion are present. Dynamic enhancement of diffusion inside separatrices can develop under a certain geometry of resonance oscillations and relatively wide resonances, leading to the fast growth of distribution tails and escape rates. The phenomenon is absent in 1-D. 10 refs., 4 figs.
Date: December 6, 1990
Creator: Gerasimov, A.
Object Type: Article
System: The UNT Digital Library
Studies on the control of plant cell enlargement by cellular parameters (open access)

Studies on the control of plant cell enlargement by cellular parameters

The overall goal of this grant was to conduct research that would illuminate the mechanisms by which the plant hormone auxin induces plant cells to enlarge. A large body of knowledge already existed concerning this process. To begin with, it had been demonstrated, primarily by this laboratory during previous grant periods, that the effect of auxin is to cause a loosening of the cell wall, which is followed by turgor-driven wall expansion and water uptake. The wall contains a series of load-bearing wall bonds which must be cleaved in order to loosen the wall. The identification of these load-bearing bonds is one goal of this research. We proposed that an initial action of auxin is to cause cells to excrete protons, and that the resulting acidification of the apoplast activated enzymes responsible for wall loosening. Evidence has been obtained that indicates that the proton excretion is due to an enhanced activity of the plasma membrane H{sup +} {minus}ATPase. A critical question is how auxin activates this enzyme. The third project concerned the role of wall calcium as part of load-bearing wall bonds. It has long been thought that apoplastic calcium crosslinks carboxyl groups in the wall pectic substances and stiffens …
Date: December 6, 1991
Creator: Cleland, R.E.
Object Type: Report
System: The UNT Digital Library
Fuel adjacency effects on fast reactor cladding mechanical properties. [LMFBR] (open access)

Fuel adjacency effects on fast reactor cladding mechanical properties. [LMFBR]

Simulated transient tests were conducted on 234 cladding specimens from EBR-II irradiated mixed oxide fuel pins; approximately 75% of the specimens were from the fuel column region, with the remainder from the plenum and below the fuel column. The cladding specimens were taken from the N-E, N-F,, PNL-9, PNL-10, PNL-11, P-23A, P-23B, P-23C, and WSA-3 fuel pins irradiated at 15.2 to 37 KW/cm to burnup levels from 11 to 110 MWd/Kg. All the fuel pins used 20% cold worked Type 316 stainless steel cladding. Irradiation temperatures ranged from 370 to 725/sup 0/C with a peak fluence of 10/sup 23/ n/cm/sup 2/ (E > 0.1 MeV).
Date: December 6, 1978
Creator: Hunter, C. W. & Johnson, G. D.
Object Type: Article
System: The UNT Digital Library
Log of exploratory hole 6, Tatum dome, Lamar County, Mississippi. Technical letter: Dribble-14 (open access)

Log of exploratory hole 6, Tatum dome, Lamar County, Mississippi. Technical letter: Dribble-14

None
Date: December 6, 1961
Creator: Armstrong, C. A.; Chafin, R. V.; Harris, H. B.; Taylor, R. E. & Stanford, J.
Object Type: Report
System: The UNT Digital Library
Monitoring conservative retrofits in single family buildings (open access)

Monitoring conservative retrofits in single family buildings

This study has provided detailed before-and-after information on the ambient and comfort conditions in nine single family buildings, and on the energy consumption of those buildings, for one or more energy conservation retrofits. The data were recorded in such a manner that as well as being able to determine the savings from the retrofits and the influence these retrofits have on the comfort conditions of the residence, the effects of the retrofits on time-of-day usage are also determinable. The following are included in appendices: a table of participant's names, site addresses and retrofit; significant dates and appropriate comments; a day of data and an annotated data set; pre-retrofit and post-retrofit audit data sheets; and usage history.
Date: December 6, 1992
Creator: Richardson, C.S.
Object Type: Report
System: The UNT Digital Library
Reference handbook: Nuclear criticality (open access)

Reference handbook: Nuclear criticality

The purpose for this handbook is to provide Rocky Flats personnel with the information necessary to understand the basic principles underlying a nuclear criticality.
Date: December 6, 1991
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Positive ion systems: state of the art and ultimate potential (open access)

Positive ion systems: state of the art and ultimate potential

The PLT or ISX-B ion source has been operated at 40-keV, 60-A, and 0.3-sec pulses with H(D) neutral injected power of 750 kW (approximately 1000 kW) on the PLT device. This report gives a brief description of this system and some future plans. (MOW)
Date: December 6, 1977
Creator: Haselton, H.H.
Object Type: Article
System: The UNT Digital Library
MFTF-B performance calculations (open access)

MFTF-B performance calculations

In this report we document the operating scenario models and calculations as they exist and comment on those aspects of the models where performance is sensitive to the assumptions that are made. We also focus on areas where improvements need to be made in the mathematical descriptions of phenomena, work which is in progress. To illustrate the process of calculating performance, and to be very specific in our documentation, part 2 of this report contains the complete equations and sequence of calculations used to determine parameters for the MARS mode of operation in MFTF-B. Values for all variables for a particular set of input parameters are also given there. The point design so described is typical, but should be viewed as a snapshot in time of our ongoing estimations and predictions of performance.
Date: December 6, 1982
Creator: Thomassen, K.I. & Jong, R.A.
Object Type: Report
System: The UNT Digital Library
Influence of centering forces on IFR hose instability (open access)

Influence of centering forces on IFR hose instability

The appropriate centering force terms are added to the ion-focused regime hose equations and their effect on hose development is calculated. It is found that while hose at very high frequencies is stabilized, the overall suppression is only moderate and other stabilization processes need to be explored.
Date: December 6, 1982
Creator: Buchanan, H.L.
Object Type: Report
System: The UNT Digital Library
Thermally Induced Structural Changes in Coal Combustion (open access)

Thermally Induced Structural Changes in Coal Combustion

Research continued on coal combustion. The project objectives are (1) to measure the effect of devolatilization temperature and time on the properties of the char and (2) characterize and quantify the effect of thermal annealing on char reactivity during char burnout under conditions of pulverized combustion. Work done during this reporting period includes: coal devolatilization/char generation; char oxidation in the thermogravimetric analyzer (TGA). Oxidation was conducted at 500{degree}C in a 5% O{sub 2}-N{sub 2} mixture at 150 cm{sup 3}/min flowrate. Under these conditions external and intraparticle diffusional limitations were negligible. Three chars obtained from the Pittsburgh No. 8 coal were used in the experiments; oxidation of single char particles in the electrodynamic balance. Experiments were carried out with particles from the Pittsburgh No. 8 char and a spherocarb'' synthetic char obtained from a vendor. The spherocarb char was used because the particles are nearly spherical thus avoiding the complications of irregular particle shape. 15 figs., 1 tab.
Date: December 6, 1990
Creator: Gavalas, G. R. & Flagan, R. C.
Object Type: Report
System: The UNT Digital Library
Microbial field pilot study. [Quarterly report], July 1, 1992--September 30, 1992 (open access)

Microbial field pilot study. [Quarterly report], July 1, 1992--September 30, 1992

The objective of this project is to perform a microbial enhanced oil recovery field pilot test in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate-reducing bacteria will be stimulated to selectively plug flow paths which have been preferentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. During this quarter an additional tracer study was performed in the field to determine pre-treatment flow paths and the first nutrients were injected. 2 figs.
Date: December 6, 1991
Creator: Knapp, R. M.; McInerney, M. J. & Menzie, D. E.
Object Type: Report
System: The UNT Digital Library
Bench-scale testing of the multi-gravity separator in combination with microcel. Fourth quarterly report, July 1, 1993--September 30, 1993 (open access)

Bench-scale testing of the multi-gravity separator in combination with microcel. Fourth quarterly report, July 1, 1993--September 30, 1993

Work this quarter included equipment installation, shakedown testing, and the beginning of the detailed testing program. With the exception of ongoing Task 4: Sample Characterization, Tasks 1 through 8 are now complete. Task 10: Detailed Testing and Task 12: Sample Analysis began this quarter and will consume all available time during the 5th quarter. Installation and testing of the process equipment, mechanical systems, as well as the electrical systems were completed. The shakedown process uncovered several necessary modifications to the circuit which were subsequently completed. Most of the changes concerned piping and valving modifications which allowed for better material flow and sampling. The circuit was operated with coal to determine the time for each unit to reach steady state. The primary objective of the proposed work is to design, install, and operate an advanced fine coal processing circuit combining the Microcel{trademark} and Multi-Gravity-Separator (MGS) technologies. Both of these processes have specific advantages as stand-alone units. For example, the Microcel column effectively removes ash-bearing mineral matter, while the MGS efficiently removes coal-pyrite composites.
Date: December 6, 1993
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Production Test IP-467-C reducing minimum downtime (open access)

Production Test IP-467-C reducing minimum downtime

The objective of the Production Tests described in this report is to evaluate the operational aspects of a proposed method for reducing minimum downtime. The excess xenon poisoning, which occurs during the first 32--38 hours after the shutdown of a reactor from present equilibrium levels, will be partially overridden by a central enriched zone whose added reactivity contribution would be compensated during normal operation by means of poison splines. The test will be performed at B Reactor.
Date: December 6, 1961
Creator: Jaklevick, J. F.
Object Type: Report
System: The UNT Digital Library
Revisions to variable goal exposure plans for production type fuel elements (open access)

Revisions to variable goal exposure plans for production type fuel elements

The exposures calculated from these plans are designed to maximize plant return on the basis that the only restraint on metal usage is that imposed by the economics of the plutonium production process and associated uranium cycle. When metal throughput in limited by ex-reactor physical capabilities to a level lower than the unrestrained requirements, exposures higher than those recommended in this document would be indicated. In essence then, these plans represent minimum economical exposures for current production fuel types, on the basis of attempting to maximize plant returns. The adjustments recommended herein, stem solely from revised estimates of the metal performance level indicies (C{sub R} values) of the various metal types.
Date: December 6, 1960
Creator: Bloomstrand, R. R.
Object Type: Report
System: The UNT Digital Library
Quantifying the Contribution of Lubrication Oil to Particulate Emissions from a Diesel Engine (open access)

Quantifying the Contribution of Lubrication Oil to Particulate Emissions from a Diesel Engine

The contribution of lubrication oil to particulate matter (PM) emissions from a Cummins B5.9 Diesel engine was measured using accelerator mass spectrometry to trace carbon isotope concentrations. The engine operated at fixed medium load (285 N-m (210 ft.lbs.) 1600 m) used 100% biodiesel fuel (B100) with a contemporary carbon-14 ({sup 14}C) concentration of 103 amol {sup 14}C/ mg C. The C concentration of the exhaust C02 and PM were 102 and 99 amol {sup 14}C/mg C, respectively. The decrease in I4C content in the PM is due to the consumption of lubrication oil which is {sup 14}C-free. Approximately 4% of the carbon in PM came from lubrication oil under these operating conditions. The slight depression in CO{sub 2} isotope content could be attributed to ambient CO{sub 2} levels and measurement uncertainty.
Date: December 6, 2002
Creator: Cheng, A. S.; Rich, D.; Dibble, R. W. & Buchholz, B. A.
Object Type: Article
System: The UNT Digital Library
Mechanical Properties of K Basin Sludge Constituents and Their Surrogates (open access)

Mechanical Properties of K Basin Sludge Constituents and Their Surrogates

A survey of the technical literature was performed to summarize the mechanical properties of inorganic components in K Basins sludge. The components included gibbsite, ferrihydrite, lepidocrocite and goethite, hematite, quartz, anorthite, calcite, basalt, Zircaloy, aluminum, and, in particular, irradiated uranium metal and uranium dioxide. Review of the technical literature showed that information on the hardness of uranium metal at irradiation exposures similar to those experienced by the N Reactor fuel present in the K Basins (typically up to 3000 MWd/t) were not available. Measurements therefore were performed to determine the hardness of coupons taken from three irradiated N Reactor uranium metal fuel elements taken from K Basins. Hardness values averaged 30 {+-} 8 Rockwell C units, similar to values previously reported for uranium irradiated to {approx}1200 MWd/t. The physical properties of candidate uranium metal and uranium dioxide surrogates were gathered and compared. Surrogates having properties closest to those of irradiated uranium metal appear to be alloys of tungsten. The surrogate for uranium dioxide, present both as particles and agglomerates in actual K Basin sludge, likely requires two materials. Cerium oxide, CeO2, was identified as a surrogate of the smaller UO2 particles while steel grit was identified for the UO2 agglomerates.
Date: December 6, 2004
Creator: Delegard, Calvin H.; Schmidt, Andrew J. & Chenault, Jeffrey W.
Object Type: Report
System: The UNT Digital Library
Low-Temperature Growth of DKDP for Improving Laser-Induced Damage resistance at 350nm (open access)

Low-Temperature Growth of DKDP for Improving Laser-Induced Damage resistance at 350nm

A set of twenty-three 20-L crystallizer runs exploring the importance of several engineering variables found that growth temperature is the most important variable controlling damage resistance of DKDP over the conditions investigated. Boules grown between 45 C and room temperature have a 50% probability of 3{omega} bulk damage that is 1.5 to 2 times higher than boules grown between 65 and 45 C. This raises their damage resistance above the NIF tripler specification for 8 J/cm{sup 2} operation by a comfortable margin. Solution impurity levels do not correlate with damage resistance for iron less than 200 ppb and aluminum less than 2000 ppb. The possibility that low growth temperatures could increase damage resistance in NIF-scale boules was tested by growing a large boule in a 1000-L crystallizer with a supplemental growth solution tank. Four samples representing early and late pyramid and prism growth are very close to the specification as best it is understood at the present. Implications of low temperature growth for meeting absorbance, homogeneity, and other material specifications are discussed.
Date: December 6, 2000
Creator: Burnham, A K; Runkel, M; Hawley-Fedder, R A; Carman, M L; Torres, R A & Whitman, P K
Object Type: Article
System: The UNT Digital Library
Full Wave Analysis of RF Signal Attenuation in a Lossy Cave using a High Order Time Domain Vector Finite Element Method (open access)

Full Wave Analysis of RF Signal Attenuation in a Lossy Cave using a High Order Time Domain Vector Finite Element Method

We present a computational study of signal propagation and attenuation of a 200 MHz dipole antenna in a cave environment. The cave is modeled as a straight and lossy random rough wall. To simulate a broad frequency band, the full wave Maxwell equations are solved directly in the time domain via a high order vector finite element discretization using the massively parallel CEM code EMSolve. The simulation is performed for a series of random meshes in order to generate statistical data for the propagation and attenuation properties of the cave environment. Results for the power spectral density and phase of the electric field vector components are presented and discussed.
Date: December 6, 2004
Creator: Pingenot, J; Rieben, R & White, D
Object Type: Article
System: The UNT Digital Library
Estimates of DWPF canister production (open access)

Estimates of DWPF canister production

Specification 1.2 of the repository program's Waste Acceptance Preliminary Specifications requires that the DWPF estimate the radionuclide inventory, and provide the error of the estimate, for each waste type (assumed to be each sludge batch). The inventory of any radionuclide is directly proportional to the number of canisters produced from that sludge batch. Thus, estimating the number of canisters to be produced from each sludge batch is an important part of complying with this specification. In this report, the number of canisters to be produced from each batch of sludge is estimated. This leads to the conclusion that approximately 5200 canisters will be produced by the DWPF through the year 2010. Thereafter, it is conservatively estimated that up to 124 canisters will be produced each year. The errors in these estimates are also discussed.
Date: December 6, 1991
Creator: Plodinec, M. J.
Object Type: Report
System: The UNT Digital Library
ALPHA SPECTROMETRIC EVALUATION OF SRM-995 AS A POTENTIAL URANIUM/THORIUM DOUBLE TRACER SYSTEM FOR AGE-DATING URANIUM MATERIALS (open access)

ALPHA SPECTROMETRIC EVALUATION OF SRM-995 AS A POTENTIAL URANIUM/THORIUM DOUBLE TRACER SYSTEM FOR AGE-DATING URANIUM MATERIALS

Uranium-233 (t{sub 1/2} {approx} 1.59E5 years) is an artificial, fissile isotope of uranium that has significant importance in nuclear forensics. The isotope provides a unique signature in determining the origin and provenance of uranium-bearing materials and is valuable as a mass spectrometric tracer. Alpha spectrometry was employed in the critical evaluation of a {sup 233}U standard reference material (SRM-995) as a dual tracer system based on the in-growth of {sup 229}Th (t{sub 1/2} {approx} 7.34E3 years) for {approx}35 years following radiochemical purification. Preliminary investigations focused on the isotopic analysis of standards and unmodified fractions of SRM-995; all samples were separated and purified using a multi-column anion-exchange scheme. The {sup 229}Th/{sup 233}U atom ratio for SRM-995 was found to be 1.598E-4 ({+-} 4.50%) using recovery-corrected radiochemical methods. Using the Bateman equations and relevant half-lives, this ratio reflects a material that was purified {approx} 36.8 years prior to this analysis. The calculated age is discussed in contrast with both the date of certification and the recorded date of last purification.
Date: December 6, 2011
Creator: Beals, D.
Object Type: Article
System: The UNT Digital Library
Deriving Daytime Variables From the AmeriFlux Standard Eddy Covariance Data Set (open access)

Deriving Daytime Variables From the AmeriFlux Standard Eddy Covariance Data Set

A gap-filled, quality assessed eddy covariance dataset has recently become available for the AmeriFluxnetwork. This dataset uses standard processing and produces commonly used science variables. This shared dataset enables robust comparisons across different analyses. Of course, there are many remaining questions. One of those is how to define 'during the day' which is an important concept for many analyses. Some studies have used local time ?for example 9am to 5pm; others have used thresholds on photosynthetic active radiation (PAR). A related question is how to derive quantities such as the Bowen ratio. Most studies compute the ratio of the averages of the latent heat (LE) and sensible heat (H). In this study, we use different methods of defining 'during the day' for GPP, LE, and H. We evaluate the differences between methods in two ways. First, we look at a number of statistics of GPP. Second, we look at differences in the derived Bowen ratio. Our goal is not science per se, but rather informatics in support of the science.
Date: December 6, 2008
Creator: Ingen, Catharine van; Agarwal, Deborah A.; Humphrey, Marty & Li, Jie
Object Type: Article
System: The UNT Digital Library