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Identifying Energy Savings Opportunities in Industrial Pumping Systems (open access)

Identifying Energy Savings Opportunities in Industrial Pumping Systems

In most industrial settings, energy consumed by pumping systems is responsible for a major part of the overall electricity bill. In some cases, the energy is used quite efficiently; in others, it is not. Facility operators may be very familiar with pumping system equipment controllability, reliability, and availability, but only marginally aware of system efficiency. There are some good reasons to increase that awareness: As budgets shrink and the intensity of both domestic and international competition increases, the pressure to find additional methods to reduce operating costs will grow. The reliability of pumps correlates with their efficiency; that is, pumps operated near their design, or best efficiency point, will tend to perform more reliably and with greater availability. More frugal and efficient use of the earth's limited natural resources is essential. The cost of energy consumed by pumps usually dominates the pump life cycle cost. Many end users, already strained to support day-to-day facility operations, lack the time and resources to perform a methodical engineering study of the many pumps within their facilities to understand their associated energy costs and the potential opportunities for energy savings. Under the auspices of the United States Department of Energy's (USDOE) Motor Challenge Program, …
Date: August 23, 1999
Creator: Casada, D.A. & McElhaney, K.L.
System: The UNT Digital Library
Numerical Analysis of Spherically Convergent Rayleigh-Taylor Experiments on the Nova Laser (open access)

Numerical Analysis of Spherically Convergent Rayleigh-Taylor Experiments on the Nova Laser

In the frame of a CEA/US DOE collaboration, convergent experiments have been done on the Nova laser. Numerical simulations with our 2D Lagrangian code FCI2 led the analysis and correctly reproduced the experimental data. From single mode 2D perturbations, ablation front Rayleigh-Taylor instability growth is computed. Moderate and high convergence ratios are addressed. The shrinking of the wavelength plays a prominent role for small convergence ratio and weakly nonlinear hydrodynamics.
Date: August 23, 1999
Creator: Cherfils, C.; Galmiche, D.; Glendinning, S. G.; Laffite, S.; Remington, B. A. & Wallace, R. J.
System: The UNT Digital Library
Isospin-Forbidden B-Delayed Proton Emission (open access)

Isospin-Forbidden B-Delayed Proton Emission

The effects of isospin-symmetry breaking on proton emission following {beta}-decay to the isobaric analog state are discussed in detail. Of particular importance is the mixing with a dense background of lower isospin states, whose properties are not well known. The possibility of observing T=4 states in even-even, N=Z nuclei, which is viable if the decay proceeds via isospin-forbidden particle emission, is also discussed.
Date: November 23, 1999
Creator: Ormand, W. E.
System: The UNT Digital Library
Ion-Beam-Induced Defects and Defect Interactions in Perovskite-Structure Titanates (open access)

Ion-Beam-Induced Defects and Defect Interactions in Perovskite-Structure Titanates

Ion-beam irradiation of perovskite structures results in the production and accumulation of defects. Below a critical temperature, irradiation also leads to a crystalline-to-amorphous transformation. The critical temperature for amorphization under 800 keV Kr{sup +} ion irradiation is 425,440 and 550 K for SrTiO{sub 3}, CaTiO{sub 3} and BaTiO{sub 3}, respectively. The results of ion-channeling studies on SrTiO{sub 3} irradiated with 1.0 MeV Au{sup 2+} ions suggest that the crystalline-to-amorphous transformation is dominated by the accumulation and interaction of irradiation-induced defects. In SiTiO{sub 3} irradiated with He{sup +} and 0{sup +} ions at 180 K, isochronal annealing studies indicate that there is significant recovery of defects on both the oxygen and cation sublattices between 200 and 400 K. These results suggest that defect recovery processes may control the kinetics of amorphization. A fit of the direct-impact/defect-stimulated model to the data for SrTiO{sub 3} suggests that the kinetics of amorphization are controlled by both a nearly athermal irradiation-assisted recovery process with an activation energy of 0.1 plus or minus 0.05 eV and a thermal defect recovery process with an activation energy of 0.6 plus or minus 0.1 eV. In SrTi0{sub 3} implanted with 40 keV H{sup +} to 5.0 x 10{sup 16} …
Date: August 23, 1999
Creator: Boatner, L. A.; Jiang, W.; Meldrum, A.; Thevuthasan, S.; Weber, W. J. & Williford, R. E.
System: The UNT Digital Library
Dosimetry quality assurance in Martin Marietta Energy Systems' centralized external dosimetry system (open access)

Dosimetry quality assurance in Martin Marietta Energy Systems' centralized external dosimetry system

External dosimetry needs at the four Martin Marietta Energy Systems facilities are served by Energy Systems Centralized External Dosimetry System (CEDS). The CEDS is a four plant program with four dosimeter distribution centers and two dosimeter processing centers. Each plant has its own distribution center, while processing centers are located at ORNL and the Y-12 Plant. The program has been granted accreditation by the Department of Energy Laboratory Accreditation Program (DOELAP). The CEDS is a TLD based system which is responsible for whole-body beta-gamma, neutron, and extremity monitoring. Beta-gamma monitoring is performed using the Harshaw/Solon Technologies model 8805 dosimeter. Effective October 1, 1992 the standard silver mylar has been replaced with an Avery mylar foil blackened on the underside with ink. This was done in an effort to reduce the number of light induced suspect readings. At this time we have little operational experience with the new blackened mylars-The CEDS neutron dosimeter is the Harshaw model 8806B. This card/holder configuration contains two TLD-600/TLD-700 chip pairs; one pair is located beneath a cadmium filter and one pair is located beneath a plastic filter. In routine personnel monitoring the CEDS neutron dosimeter is always paired with a CEDS beta-gamma dosimeter.The CEDS extremity …
Date: October 23, 1992
Creator: Souleyrette, M.L.
System: The UNT Digital Library
Securing America's Access to Space (open access)

Securing America's Access to Space

We review pertinent aspects of the history of the space launch capabilities of the United States and survey its present status and near-term outlook. Steps which must be taken, pitfalls which much be avoided, and a core set of National options for re-acquiring in the near term the capability to access the space environment with large payloads are discussed. We devote considerable attention to the prospect of creating an interim heavy-lift space launch vehicle of at least 100,000 pound payload-orbiting capacity to serve National needs during the next dozen years, suggesting that such a capability can be demonstrated within 5 years for less than $1 B. Such capability will apparently be essential for meeting the first-phase goals of the President's Space Exploration Initiative. Some other high-leverage aspects of securing American access to space are also noted briefly, emphasizing unconventional technological approaches of presently high promise.
Date: May 23, 1990
Creator: Rendine, Michael & Wood, Lowell
System: The UNT Digital Library
The use of diffraction efficiency theory in the design of soft x-ray monochromators (open access)

The use of diffraction efficiency theory in the design of soft x-ray monochromators

In general, the diffraction efficiency of gratings is limited by the constraints imposed by the type of geometry used to scan the photon energy. In the simplest example, the spherical grating monochromator (SGM), the deviation angle, the grating groove width and depth and the groove density are all constrained by considerations of the maximum photon energy and the tuning range for individual gratings. We have examined the case in which these parameters are unconstrained, resulting in predictions of the ultimate performance of lamellar type gratings for groove densities from 300 to 2400 1/mm for gold and nickel coatings. The differential method of Neviere et al was used for modeling the behavior of the gratings and justification is presented for this by rigorous comparison with measurements. The implications of these results for future monochromators based on a variable included angle geometry are discussed.
Date: August 23, 1993
Creator: Padmore, H. A.; Martynov, V. & Hollis, K.
System: The UNT Digital Library
[Recent results and near term expectations in tokamak research in the US, Europe and Japan] (open access)

[Recent results and near term expectations in tokamak research in the US, Europe and Japan]

This report discusses the scientific and economic feasibility of fusion energy, especially in regards to the tokamak reactor.
Date: June 23, 1993
Creator: Meade, D.
System: The UNT Digital Library
Freeze-out and the failure of Richtmyer`s prescription (open access)

Freeze-out and the failure of Richtmyer`s prescription

In the standard Richtmyer-Meshkov instability, perturbations at a shocked interface grow after the passage of a shock. Freeze-out refers to the phenomenon whereby the perturbations do not grow, i.e., freeze-out, after the passage of a shock. This is fairly straightforward, at least theoretically (no experiments have been done so far) in a doubly shocked system. The first shock induces a growth which can be completely neutralized by a second shock, provided that the direction and the strength and timing of the second shock are properly chosen. This type of double-shock freeze-out occurs in compressible as well as incompressible fluids, and is easy to understand. Somewhat more subtle is single-shock freeze-out; in the pursuit of this phenomenon, the author found that in certain cases Richtmyer`s prescription fails to give the correct growth rate.
Date: April 23, 1993
Creator: Mikaelian, K. O.
System: The UNT Digital Library
CP violation outside the standard model phenomenology for pedestrians (open access)

CP violation outside the standard model phenomenology for pedestrians

So far the only experimental evidence for CP violation is the 1964 discovery of K{sub L}{yields}2{pi} where the two mass eigenstates produced by neutral meson mixing both decay into the same CP eigenstate. This result is described by two parameters {epsilon} and {epsilon}{prime}. Today {epsilon} {approx} its 1964 value, {epsilon}{prime} data are still inconclusive and there is no new evidence for CP violation. One might expect to observe similar phenomena in other systems and also direct CP violation as charge asymmetries between decays of charge conjugate hadrons H{sup {+-}} {yields} f{sup {+-}}. Why is it so hard to find CP violation? How can B Physics help? Does CP lead beyond the standard model? The author presents a pedestrian symmetry approach which exhibits the difficulties and future possibilities of these two types of CP-violation experiments, neutral meson mixing and direct charge asymmetry: what may work, what doesn`t work and why.
Date: September 23, 1993
Creator: Lipkin, H. J.
System: The UNT Digital Library
Ion exchange properties of Wyodak premium coal samples (open access)

Ion exchange properties of Wyodak premium coal samples

Low rank coals (lignite and subbituminous) contain exchangeable cations. A sample of {minus}20+200 mesh Argonne Premium Wyodak coal was washed with nitric acid in a burette fitted with a coarse glass frit at the base of the graduations to remove the exchangeable cations from the system. The eluent was passed to a flow-through pH electrode and a titration curve was obtained on a computer file. A series of electrodes (pH, calcium, sodium and potassium) were used in separate experiments to follow the elution from the coal. Some implications for coal structure are also indicated.
Date: August 23, 1993
Creator: Vorres, K. S.
System: The UNT Digital Library
New methods in plasma simulation (open access)

New methods in plasma simulation

The development of implicit methods of particle-in-cell (PIC) computer simulation in recent years, and their merger with older hybrid methods have created a new arsenal of simulation techniques for the treatment of complex practical problems in plasma physics. The new implicit hybrid codes are aimed at transitional problems that lie somewhere between the long time scale, high density regime associated with MHD modeling, and the short time scale, low density regime appropriate to PIC particle-in-cell techniques. This transitional regime arises in ICF coronal plasmas, in pulsed power plasma switches, in Z-pinches, and in foil implosions. Here, we outline how such a merger of implicit and hybrid methods has been carried out, specifically in the ANTHEM computer code, and demonstrate the utility of implicit hybrid simulation in applications. 25 refs., 5 figs.
Date: February 23, 1990
Creator: Mason, R. J.
System: The UNT Digital Library
The Westinghouse Waste Isolation Division Management and Supervisor Training Program (open access)

The Westinghouse Waste Isolation Division Management and Supervisor Training Program

The Westinghouse Waste Isolation Division (WID) is the management and operating contractor (MOC) for the Department of Energy`s (DOE`s) Waste Isolation Plant (WIPP). Managers and supervisors at DOE facilities such as the WIPP are required to complete extensive training. To meet this requirement, WID created a self-paced, self-study program known as Management and Supervisor Training (MAST). All WID managers and supervisors are required to earn certification through the MAST program. Selected employees are permitted to participate in MAST with prior approval from their manager and the Human Resources Manager. Initial MAST certification requires the completion of 31 modules. MAST participants check out modules and read them when convenient. When they are prepared, participants take module examinations. To receive credit for a given module, participants must score at least 80 percent on the examination. Lessons learned from the development, implementation, and administration are presented in this paper.
Date: April 23, 1992
Creator: Gilbreath, B.
System: The UNT Digital Library
An environmental assessment strategy for the identification of pollution prevention opportunities in the southern Urals Region of Russia (open access)

An environmental assessment strategy for the identification of pollution prevention opportunities in the southern Urals Region of Russia

The serious environmental problems of the South Urals Region of Russia have been broadly described in a report coauthored by Russian weapons scientists. The importance of taking the first steps to prevent further environmental damage and adverse public health effects has been recognized by the international scientific community. Scientists at the Lawrence Livermore National Laboratory have initiated a project to assist the Russians in their pollution prevention efforts. The specific objectives of this project are to: (1) conduct a pragmatic survey of the industrial and governmental pollution sources in a limited geographic region of the South Urals and (2) identify the priorities for pollution prevention and for food and water supply improvements at distribution points. The emphasis is on preventing adverse impacts to human health and improving industrial productivity. This project focuses on immediate pollution problems resulting from current operations and their solutions, not on long-term research related to the large-scale cleanup of legacy wastes. The project emphasizes near-term cost effective solutions to prevent pollution while longer term research aimed at contamination from past practices is pursued by other scientists. The project is being conducted in collaboration with environmental and physical scientists from institutes associated with the Ural Branch of …
Date: August 23, 1993
Creator: Gonzalez, M. A. & Ott, R. L.
System: The UNT Digital Library
Towards a theory of quark and lepton masses (open access)

Towards a theory of quark and lepton masses

Has any progress been made on understanding and predicting the 13 parameters which describe the observed masses and mixing angles of the quarks and leptons? Arguments are given in favor of pursuing schemes in which grand unified and family symmetries provide many relations among these 13 parameters. A sequence of simple assumptions leads to a supersymmetric SO(10) theory with 8 predictions: tan {beta}, M{sub t}, V{sub cb}, M{sub s},M{sub s}/M{sub d}, M{sub u}/M{sub d}, V{sub ub} and the amount of CP violation J. These predictions are presented, together with experiments which will test them.
Date: February 23, 1993
Creator: Hall, L. J.
System: The UNT Digital Library
An automatic contact algorithm in DYNA3D for impact problems (open access)

An automatic contact algorithm in DYNA3D for impact problems

This paper presents a new approach for the automatic definition and treatment of mechanical contact in explicit nonlinear finite element analysis. Automatic contact offers the benefits of significantly reduced model construction time and fewer opportunities for user error, but faces significant challenges in reliability and computational costs. Key aspects of the proposed new method include automatic identification of adjacent and opposite surfaces in the global search phase, and the use of a well-defined surface normal which allows a consistent treatment of shell intersection and corner contact conditions without a ad-hoc rules. The paper concludes with three examples which illustrate the performance of the newly proposed algorithm in the public DYNA3D code.
Date: July 23, 1993
Creator: Whirley, R. G. & Engelmann, B. E.
System: The UNT Digital Library
Implementation and performance of a domain decomposition algorithm in Sisal (open access)

Implementation and performance of a domain decomposition algorithm in Sisal

Sisal is a general-purpose functional language that hides the complexity of parallel processing, expedites parallel program development, and guarantees determinacy. Parallelism and management of concurrent tasks are realized automatically by the compiler and runtime system. Spatial domain decomposition is a widely-used method that focuses computational resources on the most active, or important, areas of a domain. Many complex programming issues are introduced in paralleling this method including: dynamic spatial refinement, dynamic grid partitioning and fusion, task distribution, data distribution, and load balancing. In this paper, we describe a spatial domain decomposition algorithm programmed in Sisal. We explain the compilation process, and present the execution performance of the resultant code on two different multiprocessor systems: a multiprocessor vector supercomputer, and cache-coherent scalar multiprocessor.
Date: September 23, 1993
Creator: DeBoni, T.; Feo, J.; Rodrigue, G. & Muller, J.
System: The UNT Digital Library
Solubility of Anthracene in Binary Alkane + 2-Ethyl-1-hexanol and Alkane + 1-Pentanol Solvent Mixtures at 298.2 K (open access)

Solubility of Anthracene in Binary Alkane + 2-Ethyl-1-hexanol and Alkane + 1-Pentanol Solvent Mixtures at 298.2 K

Article on the solubility of anthracene in binary alkane + 2-ethyl-1-hexanol and alkane + 1-pentanol solvent mixtures at 298.2 K.
Date: April 23, 1998
Creator: Roy, Lindsay Elizabeth; Hernández, Carmen E.; Reddy, Gaddum D.; Sanders, Jessica T.; Deng, Taihe; Tuggle, Michael B. et al.
System: The UNT Digital Library
Frequency Interactions to Explain Madden Julian Oscillations and Intra Seasonal Oscillations. (open access)

Frequency Interactions to Explain Madden Julian Oscillations and Intra Seasonal Oscillations.

None
Date: March 23, 1998
Creator: Barr-Kumarakulasinghe, S. A.
System: The UNT Digital Library
Gms-5 Ir and Visible Imagery for November 1996-February 1997 From the Arm External Data Center. (open access)

Gms-5 Ir and Visible Imagery for November 1996-February 1997 From the Arm External Data Center.

None
Date: March 23, 1998
Creator: Barr-Kumarakulasinghe, S. A.
System: The UNT Digital Library
Amorphization of Laves-Phase Precipitates in Zircaloy-4 by Neutron Irradiation (open access)

Amorphization of Laves-Phase Precipitates in Zircaloy-4 by Neutron Irradiation

Examination of corrosion coupons by transmission electron microscopy after their exposure in the Idaho Advanced Test Reactor (ATR) has broadened the Zircaloy-4 precipitate-amorphization database and validated a new kinetic model for previously unavailable values of temperature and fast-neutron flux. The model describes the amorphization of Zr(Fe,Cr){sub 2} intermetallic precipitates in zirconium alloys as a dynamic competition between radiation damage and thermal annealing that leaves some iron atoms available for flux-assisted diffusion to the zirconium matrix. It predicts the width of the amorphous zone as a function of neutron flux (E>1 MeV), temperature, and time. In its simplest form, the model treats the crystalline/amorphous and precipitate/matrix interfaces as parallel planes, and its accuracy decreases for small precipitates and high fluence as the amorphous-zone width approaches precipitate dimensions. The simplest form of the model also considers diffusion to be rate-determining. This is an accurate approximation for steady-state conditions or slow changes in flux and temperature, but inappropriate for the analysis of faster transients. The paper addresses several difficulties inherent in measuring amorphous-zone width, and utilizes the expanded database to evaluate the improvements in predictive accuracy available through both conversion of the model to spherical coordinates and extension of its time dependency.
Date: April 23, 1999
Creator: Peters, H. R.; Taylor, D. F. & Yang, Walter J. S.
System: The UNT Digital Library
Measurement of the Fundamental Parameters for the Film-Rupture/Oxidation Mechanism (open access)

Measurement of the Fundamental Parameters for the Film-Rupture/Oxidation Mechanism

Identification of the mechanism responsible for primary water stress corrosion cracking (PWSCC) in nickel-base alloys is a controversial topic. Numerous mechanisms, including the film-rupture/oxidation (i.e., slip-oxidation or slip-dissolution) mechanism, have been proposed to explain PWSCC. According to this mechanism, the observed sensitivity of PWSCC to material and environmental factors may be explained by the combined effects of repassivation kinetics, oxide rupture strain, and crack tip strain rate (which includes creep). Previous research has shown that increasing the Cr content of Ni-9%Fe-Cr from 16 to 30 wt% strongly decreases PWSCC susceptibility. Consequently, measurements of these three fundamental parameters (repassivation, oxide rupture, and creep) were performed as a function of Cr content, and SCC crack growth rates were predicted on the basis of the resulting data. This paper illustrates that considering these three parameters concurrently may contribute to the understanding of Cr effects on PWSCC of Ni-base alloys. However, it is not clear whether the film-rupture/oxidation mechanism can adequately predict the observed crack growth rates for Alloy 600 at 338 C.
Date: April 23, 1999
Creator: Attanasio, S. A.; Fish, J. S.; Morton, D. S.; Rosecrans, P. M.; Was, G. S.; Wilkening, W. W. et al.
System: The UNT Digital Library
Step structure of GaInAsSb grown by OMVPE (Organometallic Vapor Phase Epitaxy) (open access)

Step structure of GaInAsSb grown by OMVPE (Organometallic Vapor Phase Epitaxy)

The microscopic surface morphology of GaInAsSb grown by organometallic vapor phase epitaxy (OMVPE)on GaSb substrates has been studied by atomic force microscopy. The effects of growth temperature, alloy composition, and substrate misorientation on the step structure were investigated. The competition between thermodynamically driven phase separation and kinetically limited surface diffusion is discussed.
Date: May 23, 1999
Creator: Charache, G.W. & Wang, C.A.
System: The UNT Digital Library
Effects of O2, H2, and N2 gases on the field emission properties of diamond-coated microtips (open access)

Effects of O2, H2, and N2 gases on the field emission properties of diamond-coated microtips

This article discusses the effects of O2, H2, and N2 gases on the field emission properties of diamond-coated microtips.
Date: August 23, 1999
Creator: Lim, Seong-Chu; Stallcup, Richard E.; Akwani, Ikerionwu A. & Pérez, José M.
System: The UNT Digital Library