Minimum Field Strength in Ultrafast Magnetization Reversal (open access)

Minimum Field Strength in Ultrafast Magnetization Reversal

Ultrafast magnetic field pulses as short as 2 ps are able to reverse the magnetization in thin in-plane magnetized cobalt films. The field pulses are applied in the plane of the film and their direction encompasses all angles with the magnetization. At right angle to the magnetization maximum torque is exerted on the spins. In this geometry a precessional magnetization reversal can be triggered by fields as small as 184 kA/m. Applications in future ultrafast magnetic recording schemes can be foreseen.
Date: June 30, 1999
Creator: Garwin, Edward L
Object Type: Report
System: The UNT Digital Library
Final report for tank 241-U-102, cores 143 and 144 (open access)

Final report for tank 241-U-102, cores 143 and 144

None
Date: August 30, 1996
Creator: Steen, F.H., Westinghouse Hanford
Object Type: Report
System: The UNT Digital Library
Small Wind Turbine Applications: Current Practice in Colorado (open access)

Small Wind Turbine Applications: Current Practice in Colorado

Numerous small wind turbines are being used by homeowners in Colorado. Some of these installations are quite recent while others date back to the federal tax-credit era of the early 1980s. Through visits with small wind turbine owners in Colorado, I have developed case studies of six small wind energy applications focusing on the wind turbine technology, wind turbine siting, the power systems and electric loads, regulatory issues, and motivations about wind energy. These case studies offer a glimpse into the current state-of-the-art of small-scale wind energy and provide some insight into issues affecting development of a wider market.
Date: September 30, 1999
Creator: Green, J.
Object Type: Article
System: The UNT Digital Library
Water-Level Monitoring Plan for the Hanford Groundwater Monitoring Project (open access)

Water-Level Monitoring Plan for the Hanford Groundwater Monitoring Project

This document presents the water-level monitoring plan for the Hanford Groundwater Monitoring Project, conducted by the Pacific Northwest National Laboratory (PNNL). Water-level monitoring of the groundwater system beneath the Hanford Site is performed to fulfill the requirements of various state and federal regulations, orders, and agreements. The primary objective of this monitoring is to determine groundwater flow rates and directions. To meet this and other objectives, water-levels are measured annually in monitoring wells completed within the unconfined aquifer system, the upper basalt-confined aquifer system, and in the lower basalt-confined aquifers for surveillance monitoring. At regulated waste units, water levels are taken monthly, quarterly, semi-annually, or annually, depending on the hydrogeologic conditions and regulatory status of a given site. The techniques used to collect water-level data are described in this document along with the factors that affect the quality of the data and the strategies employed by the project to minimize error in the measurement and interpretation of water levels. Well networks are presented for monitoring the unconfined aquifer system, the upper basalt-confined aquifer system, and the lower basalt-confined aquifers, all at a regional scale (surveillance monitoring), as well as the local-scale well networks for each of the regulated waste units …
Date: September 30, 1999
Creator: Newcomer, D.R.; McDonald, J.P. & Chamness, M.A.
Object Type: Report
System: The UNT Digital Library
Maintenance of the Hanford cone penetrometer platform during fiscal year 1999 (open access)

Maintenance of the Hanford cone penetrometer platform during fiscal year 1999

This SOW describes services requested of Applied Research and Associates, Inc. (ARA), as a commercial provider of cone penetrometer equipment and services, to provide routine inspection and minimum preventive maintenance on the Hanford CP Platform (CPP) during Fiscal Year 1999. This SOW specifically pertains to the maintenance of the CPP and associated support equipment and is limited in scope to routine preventive maintenance and identification of any deficiencies. ARA is the original manufacturer of the CPP and will conduct this work following the vendor-prepared maintenance schedule.
Date: November 30, 1998
Creator: IWATATE, D.F.
Object Type: Report
System: The UNT Digital Library
Advanced secondary recovery demonstration for the Sooner Unit. Progress report, July 1--September 30, 1995 (open access)

Advanced secondary recovery demonstration for the Sooner Unit. Progress report, July 1--September 30, 1995

The objective of this project is to increase production from the Cretaceous ``D`` Sand in the Denver-Julesburg (D-J) Basin through geologically targeted infill drilling and improved reservoir management of waterflood operations. This project involves multi-disciplinary reservoir characterization using high-density 3-D seismic, detailed stratigraphy and reservoir simulation studies. Infill drilling, water-injection conversion and recompleting some wells to add short-radius laterals will be based on the results of the reservoir characterization studies. Production response will be evaluated using reservoir simulation and production tests. Technology transfer will utilize workshops, presentations and technical papers which will emphasize the economic advantages of implementing the demonstrated technologies. The success of this project and effective technology transfer should prompt-re-appraisal of older waterflood projects and implementation of new projects in oil provinces such as the D-J Basin. Three wells have been drilled by the project based on 3-D seismic and integrated reservoir characterization study. Oil production has increased in September to 54.0 m{sup 3}/D (340 bopd) after the completion of the SU 21-16-9. Combination-attribute maps from 3-D seismic data closely predicted the net-pay thickness of the new well. Inter-well tracer tests with sodium bromide indicate a high-permeability channel between two wells. An oral presentation was made at the …
Date: September 30, 1995
Creator: Sippel, M.A. & Cammon, T.J.
Object Type: Report
System: The UNT Digital Library
The cost of ethanol production from lignocellulosic biomass -- A comparison of selected alternative processes. Final report (open access)

The cost of ethanol production from lignocellulosic biomass -- A comparison of selected alternative processes. Final report

The purpose of this report is to compare the cost of selected alternative processes for the conversion of lignocellulosic biomass to ethanol. In turn, this information will be used by the ARS/USDA to guide the management of research and development programs in biomass conversion. The report will identify where the cost leverages are for the selected alternatives and what performance parameters need to be achieved to improve the economics. The process alternatives considered here are not exhaustive, but are selected on the basis of having a reasonable potential in improving the economics of producing ethanol from biomass. When other alternatives come under consideration, they should be evaluated by the same methodology used in this report to give fair comparisons of opportunities. A generic plant design is developed for an annual production of 25 million gallons of anhydrous ethanol using corn stover as the model substrate at $30/dry ton. Standard chemical engineering techniques are used to give first order estimates of the capital and operating costs. Following the format of the corn to ethanol plant, there are nine sections to the plant; feed preparation, pretreatment, hydrolysis, fermentation, distillation and dehydration, stillage evaporation, storage and denaturation, utilities, and enzyme production. There are …
Date: April 30, 1993
Creator: Grethlein, H.E. & Dill, T.
Object Type: Report
System: The UNT Digital Library
Dielectric Properties and Depoling Characteristics of Pb(Zr(0.95)Ti(0.05))O(3) Based Ceramics: Near-Critical Grain Size Behavior (open access)

Dielectric Properties and Depoling Characteristics of Pb(Zr(0.95)Ti(0.05))O(3) Based Ceramics: Near-Critical Grain Size Behavior

Chemically prepared Pb(Zr{sub 0.951}Ti{sub 0.949}){sub 0.982}Nb{sub 0.018}O{sub 3} ceramics were fabricated that were greater than 95% dense for sintering temperatures as low as 925 C. Achieving high density at low firing temperatures permitted isolation of the effects of grain size, from those due to porosity, on both dielectric and pressure induced transformation properties. Specifically, two samples of similar high density, but with grain sizes of 0.7 {micro}m and 8.5 {micro}m, respectively, were characterized. The hydrostatic ferroelectric (FE) to antiferroelectric (AFE) transformation pressure was substantially less (150 MPa) for the lower grain size material than for the larger grain size material. In addition, the dielectric constant increased and the Curie temperature decreased for the sample with lower grain size. All three properties: dielectric constant magnitude, Curie point shift, and FE to AFE phase transformation pressure were shown to be semi-quantitatively consistent with internal stress levels on the order of 100 MPa.
Date: September 30, 1999
Creator: Rodriguez, Mark A.; Scofield, Timothy W.; Tuttle, Bruce A.; Voigt, James A.; Yang, Pin & Zeuch, David H.
Object Type: Article
System: The UNT Digital Library
Numerical simulation of MHD for electromagnetic edge dam in continuous casting. (open access)

Numerical simulation of MHD for electromagnetic edge dam in continuous casting.

A computer model was developed to predict eddy currents and fluid flows in molten steel. The model was verified by comparing predictions with experimental results of liquid-metal containment and fluid flow in electromagnetic (EM) edge dams (EMDs) designed at Inland Steel for twin-roll casting. The model can optimize the EMD design so it is suitable for application, and minimize expensive, time-consuming full-scale testing. Numerical simulation was performed by coupling a three-dimensional (3-D) finite-element EM code (ELEKTRA) and a 3-D finite-difference fluids code (CaPS-EM) to solve heat transfer, fluid flow, and turbulence transport in a casting process that involves EM fields. ELEKTRA is able to predict the eddy-current distribution and the electromagnetic forces in complex geometries. CaPS-EM is capable of modeling fluid flows with free surfaces. Results of the numerical simulation compared measurements obtained from a static test.
Date: March 30, 1999
Creator: Chang, F. C.
Object Type: Article
System: The UNT Digital Library
Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells Multiple Hydraulic Fractures (open access)

Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells Multiple Hydraulic Fractures

This project attempts to demonstrate the effectiveness of exploiting thin-layered, low-energy deposits at the distal margin of a prograding turbidite complex through the use of hydraulically fractured horizontal or high-angle wells. The combination of a horizontal or high-angle well and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thin interbedded layers and the wellbore. A high-angle well will be drilled in the fan-margin portion of a slope-basin clastic reservoir and will be completed with multiple hydraulic-fracture treatments. Geologic modeling, reservoir characterization, and fine-grid reservoir simulation will be used to select the well location and orientation. Design parameters for the hydraulic-fracture treatments will be determined, in part, by fracturing an existing test well. Fracture azimuth will be predicted by passive seismic monitoring of a fracture-stimulation treatment in the test well using logging tools in an offset well.
Date: October 30, 1997
Creator: Laue, Mike L.
Object Type: Report
System: The UNT Digital Library
Practical superconductor development for electrical power applications quarterly report for the period ending September 30, 1997 (open access)

Practical superconductor development for electrical power applications quarterly report for the period ending September 30, 1997

This is a multiyear experimental research program focused on improving relevant material properties of high-T{sub c} superconductors and on development of fabrication methods that can be transferred to industry for production of commercial conductors. The development of teaming relationships through agreements with industrial partners is a key element of this program. Recent work on strain tolerance of Bi-2223 tapes, AC downlink construction, fundamental studies of flux pinning, and application of coils from powder-in-tube tapes to particle detectors is discussed.
Date: October 30, 1997
Creator: unknown
Object Type: Report
System: The UNT Digital Library
NANOMETER PRECISION IN LARGE SURFACE PROFILOMETRY. (open access)

NANOMETER PRECISION IN LARGE SURFACE PROFILOMETRY.

The Long Trace Profiler (LTP) is in use at many synchrotron radiation (SR) laboratories throughout the world and by a number of manufacturers who specialize in fabricating grazing incidence mirrors for SR and x-ray telescope applications. Recent improvements in the design and operation of the LTP system have reduced the statistical error in slope profile measurement to the 1 standard deviation level of 0.3 microradian for 0.5 meter long mirrors. This corresponds to a height error on the order of 10-20 nanometers. This level of performance allows one to measure with confidence the absolute shape of large cylindrical aspheres and spheres that have kilometer radii of curvature in the axial direction. The LTP is versatile enough to make measurements of a mirror in the face up, sideways, and face down configurations. We will illustrate the versatility of the current version of the instrument, the LTP II, and present results from two new versions of the instrument: the in situ LTP (ISLTP) and the Vertical Scan LTP (VSLTP). Both of them are based on the penta prism LTP (ppLTP) principle that utilizes a stationary optical head and moving penta prism. The ISLTP is designed to measure the distortion of high heat …
Date: August 30, 1999
Creator: TAKACS,P.Z.
Object Type: Article
System: The UNT Digital Library
{sup 129}I Interlaboratory comparison: phase I and phase II (open access)

{sup 129}I Interlaboratory comparison: phase I and phase II

An interlaboratory comparison exercise for {sup 129}I was organized and conducted. Nine laboratories participated in the exercise to either a full or limited extent. In Phase I of the comparison, 11 samples were measured. The suite of samples contained both synthetic ''standard type'' materials (i.e., AgI) and environmental materials. The isotopic {sup 129}I/{sup 127}I ratios of the samples varied from 10{sup {minus}8} to 10{sup {minus}14}. In this phase, each laboratory was responsible for its own chemical preparation of the samples. In Phase I, the {sup 129}I AMS measurements for prepared AgI were in good agreement. However, large discrepancies were seen in {sup 129}I AMS measurements of environmental samples. Because of the large discrepancies seen in the Phase I {sup 129}I intercomparison, a subsequent study was conducted. In Phase II of the {sup 129}I intercomparison, three separate laboratories prepared AgI from two environmental samples (IAEA 375 soil and maples leaves). Each laboratory used its own chemical preparation method with each of the methods being distinctly different. The resulting six samples (two sets of three) were then re-distributed to the participating {sup 129}I AMS facilities and {sup 129}I/{sup 127}I ratios measured. Results and discussion of both the Phase I and Phase II …
Date: September 30, 1999
Creator: Caffee, M W & Roberts, M L
Object Type: Article
System: The UNT Digital Library
The measurement and analysis of wavefront structure from large aperture ICF optics (open access)

The measurement and analysis of wavefront structure from large aperture ICF optics

This paper discusses the techniques, developed over the past year, for high spatial resolution measurement and analysis of the transmitted and/or reflected wavefront of large aperture ICF optical components. Parts up to 400 mm {times} 750 mm have been measured and include: laser slabs, windows, KDP crystals and lenses. The measurements were performed using state-of-the-art commercial phase shifting interferometers at a wavelength of 633 {mu}m. Both 1 and 2-D Fourier analysis have been used to characterize the wavefront; specifically the Power Spectral Density, (PSD), function was calculated. The PSDs of several precision optical components will be shown. The PSD(V) is proportional to the (amplitude){sup 2} of components of the Fourier frequency spectrum. The PSD describes the scattered intensity and direction as a function of scattering angle in the wavefront. The capability of commercial software is limited to 1-D Fourier analysis only. We are developing our own 2-D analysis capability in support of work to revise specifications for NIF optics. 2-D analysis uses the entire wavefront phase map to construct 2D PSD functions. We have been able to increase the signal-to-noise relative to 1-D and can observe very subtle wavefront structure.
Date: May 30, 1995
Creator: Wolfe, C. R. & Lawson, J. K.
Object Type: Article
System: The UNT Digital Library
Thermodynamic and rheological properties of solid-liquid systems in coal processing. Final technical report (open access)

Thermodynamic and rheological properties of solid-liquid systems in coal processing. Final technical report

The work on this project was initiated on September 1, 1991. The project consisted of two different tasks: (1) Development of a model to compute viscosities of coal derived liquids, and (2) Investigate new models for estimation of thermodynamic properties of solid and liquid compounds of the type that exist in coal, or are encountered during coal processing. As for task 1, a model for viscosity computation of coal model compound liquids and coal derived liquids has been developed. The detailed model is presented in this report. Two papers, the first describing the pure liquid model and the second one discussing the application to coal derived liquids, are expected to be published in Energy & Fuels shortly. Marginal progress is reported on task 2. Literature review for this work included compilation of a number of data sets, critical investigation of data measurement techniques available in the literature, investigation of models for liquid and solid phase thermodynamic computations. During the preliminary stages it was discovered that for development of a liquid or solid state equation of state, accurate predictive models for a number of saturation properties, such as, liquid and solid vapor pressures, saturated liquid and solid volumes, heat capacities of …
Date: June 30, 1995
Creator: Kabadi, V. N.
Object Type: Report
System: The UNT Digital Library
Atmospheric Pressure Chemical Vapor Deposition of CdTe for High-Efficiency Thin-Film PV Devices; Annual Report, 26 January 1998-25 January 1999 (open access)

Atmospheric Pressure Chemical Vapor Deposition of CdTe for High-Efficiency Thin-Film PV Devices; Annual Report, 26 January 1998-25 January 1999

ITN's 3-year project, titled ''Atmospheric Pressure Chemical Vapor Deposition (APCVD) of CdTe for High-Efficiency Thin-Film Photovoltaic (PV) Devices,'' has the overall objectives of improving thin-film CdTe PV manufacturing technology and increasing CdTe PV device power conversion efficiency. CdTe deposition by APCVD employs the same reaction chemistry as has been used to deposit 16%-efficient CdTe PV films, i.e., close-spaced sublimation, but employs forced convection rather than diffusion as a mechanism of mass transport. Tasks of the APCVD program center on demonstrating APCVD of CdTe films, discovering fundamental mass-transport parameters, applying established engineering principles to the deposition of CdTe films, and verifying reactor design principles that could be used to design high-throughput, high-yield manufacturing equipment. Additional tasks relate to improved device measurement and characterization procedures that can lead to a more fundamental understanding of CdTe PV device operation, and ultimately, to higher device conversion efficiency and greater stability. Specifically, under the APCVD program, device analysis goes beyond conventional one-dimensional device characterization and analysis toward two-dimension measurements and modeling. Accomplishments of the first year of the APCVD subcontract include: selection of the Stagnant Flow Reactor design concept for the APCVD reactor, development of a detailed reactor design, performance of detailed numerical calculations simulating …
Date: September 30, 1999
Creator: Meyers, P. V.; Kee, R.; Wolden, C.; Raja, L.; Kaydanov, V.; Ohno, T. et al.
Object Type: Report
System: The UNT Digital Library
Properties of UNiAlD{sub 2.1} and UNiAlH{sub 2.3}. (open access)

Properties of UNiAlD{sub 2.1} and UNiAlH{sub 2.3}.

None
Date: July 30, 1999
Creator: Bordallo, H. N.; Christianson, A.; Drulis, H.; Havela, L.; Iwasieczko, W.; Kolomiets, A. V. et al.
Object Type: Article
System: The UNT Digital Library
Using x-ray microprobes for environmental research. (open access)

Using x-ray microprobes for environmental research.

Understanding the fate of environmental contaminants is of fundamental importance in the development and evaluation of effective remediation strategies. Among the factors influencing the transport of these contaminants are the chemical speciation of the sample and the chemical and physical attributes of the surrounding medium. Characterization of the spatial distribution and chemical speciation at micron and submicron resolution is essential for studying the microscopic physical, geological, chemical, and biological interfaces that play a crucial role in determining contaminant fate and mobility. Hard X-ray spectroscopy and imaging are powerful techniques for the element-specific investigation of complex environmental samples at the needed micron and submicron resolution. An important advantage of these techniques results from the large penetration depth of hard X-rays in water. This minimizes the requirements for sample preparation and allows the detailed study of hydrated samples. This paper discusses some current problems in environmental science that can be addressed by using synchrotron-based X-ray imaging and spectroscopy. These concepts are illustrated by the results of recent X-ray microscopy studies at the Advanced Photon Source.
Date: July 30, 1998
Creator: Cai, Z.; Jastrow, J.; Kemner, K. M.; Lai, B.; Lee, H.-R.; Legnini, D. G. et al.
Object Type: Article
System: The UNT Digital Library
DISSS/ET modernization feasibility of adapting existing software and hardware technologies (open access)

DISSS/ET modernization feasibility of adapting existing software and hardware technologies

The Fission Energy and Systems Safety Program (FESSP) at LLNL was funded by the DOE Office of Safeguards and Security to develop an integrated system, hereafter referred to as the Security Clearance Electronic Processing, Transfer, Evaluation, and Recordkeeping (SCEPTER) System, for the electronic collection and transfer of personnel security data between clearance offices at contractor sites and DOE field offices and the Office of Personnel Management(OPM). This system will use existing software and hardware technologies where feasible. The project will consist of three phases. The first phase will investigate user needs, determine the feasibility of using existing technologies, and define project requirements. The second phase will be a pilot project to develop the computer systems and procedures required to automate the security clearance work flow within DOE and between DOE and OPM. Once the pilot system is implemented and tested, the decision to extend the system throughout DOE can be made. This third phase, the extension to a full production system, will require the investment of considerable funds in equipment and in the development of both a computer system and management infrastructure to support its successful operation. This investment will be undertaken only after the pilot system is operational and …
Date: September 30, 1993
Creator: Strait, R.S.
Object Type: Report
System: The UNT Digital Library
Advanced Oil Recovery Technologies for Improved Recovery From Slope Basin Clastic reservoirs, Nash Draw Brushy Canyon Pool, Eddy County, New Mexico (open access)

Advanced Oil Recovery Technologies for Improved Recovery From Slope Basin Clastic reservoirs, Nash Draw Brushy Canyon Pool, Eddy County, New Mexico

The overall goal of this project is to demonstrate that an advanced development drilling and pressure maintenance program based on advanced reservoir management methods can significantly improve oil recovery. The plan included developing a control area using standard reservoir management techniques and comparing its performance to an area developed using advanced methods. A key goal is to transfer advanced methodologies to oil and gas producers in the Permian Basin and elsewhere, and throughout the US oil and gas industry.
Date: April 30, 1998
Creator: Murphy, Mark B.
Object Type: Report
System: The UNT Digital Library
X-ray diffraction studies using diamond coated rhenium gasket to megabar pressures (open access)

X-ray diffraction studies using diamond coated rhenium gasket to megabar pressures

X-ray diffraction studies at megabar pressures are limited by the sample thickness between the diamond anvils. High strength gaskets are desirable to improve the quality of x-ray diffraction data. We present a technique which employs a microwave plasma chemical vapor deposited diamond layer on one side of a rhenium gasket. As a test case, we show energy dispersive x-ray diffraction data on rare earth metal neodymium to 153 GPa using a synchrotron source. The increased sample thickness results in an unambiguous crystal structure determination of a monoclinic phase in neodymium above 75 GPa. [chemical vapor deposition, diamond, rhenium gasket, x-ray diffraction, neodymium]
Date: September 30, 1999
Creator: Akella, J; Catledge, S A; Chesnut, G N; Prokop, H; Vohra, Y K & Weir, S T
Object Type: Article
System: The UNT Digital Library
Federal Radiological Monitoring and Assessment Center Phased Response Operations (open access)

Federal Radiological Monitoring and Assessment Center Phased Response Operations

A Federal Radiological Monitoring and Assessment Center (FRMAC) is established in response to the Lead Federal Agency (LFA) or state request when a major radiological emergency is anticipated of has occurred. The FRMAC becomes a coalition of federal off-site monitoring and assessment activities to assist the LFA, state(s), local, and tribal authorities. State, local, and tribal authorities are invited to co-locate and prioritize monitoring and assessment efforts in the FRMAC. The Department of Energy is tasked by the Federal Radiological Emergency Response Plan to coordinate the FRMAC.
Date: June 30, 1999
Creator: Riland, C. A. & Bowman, D. R.
Object Type: Article
System: The UNT Digital Library
Dry lubricant films for aluminum forming. (open access)

Dry lubricant films for aluminum forming.

During metal forming process, lubricants are crucial to prevent direct contact, adhesion, transfer and scuffing of workpiece materials and tools. Boric acid films can be firmly adhered to the clean aluminum surfaces by spraying their methanol solutions and provide extremely low friction coefficient (about 0.04). The cohesion strengths of the bonded films vary with the types of aluminum alloys (6061, 6111 and 5754). The sheet metal forming tests indicate that boric acid films and the combined films of boric acid and mineral oil can create larger strains than the commercial liquid and solid lubricants, showing that they possess excellent lubricities for aluminum forming. SEM analyses indicate that boric acid dry films separate the workpiece and die materials, and prevent their direct contact and preserve their surface qualities. Since boric acid is non-toxic and easily removed by water, it can be expected that boric acid films are environmentally friendly, cost effective and very efficient lubricants for sheet aluminum cold forming.
Date: March 30, 1999
Creator: Wei, J.; Erdemir, A. & Fenske, G. R.
Object Type: Article
System: The UNT Digital Library
Temperature Effects on Chemical Structure and Motion in Coal. Quarterly Report, July--September 1995 (open access)

Temperature Effects on Chemical Structure and Motion in Coal. Quarterly Report, July--September 1995

Research continued on the temperature effects on chemical structure and motion in coal. This report presents results on a new 2D spin diffusion experiment, an RF heating experiment, and some improvements in the software for NMR spectrometer control and data processing.
Date: September 30, 1995
Creator: Maciel, G.E.
Object Type: Report
System: The UNT Digital Library