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Report on the workshop for potential users of the Argonne Linear Free-Electron Laser Facility (ALFF).
On October 30-31, 2003 over 60 scientists gathered at ANL to discuss potential science that could be done with a fully operational user facility dedicated to delivering widely tunable, short pulse, high peak power vacuum ultraviolet light. The charge given to the workshop by J. Murray Gibson, ANL Associate Lab Director for the Advanced Photon Source, included the following two points: (1) What are the scientifically important experiments that can only be done with the proposed ALFF facility? (2) Are the combined ALFF characteristics of pulse energy, tunability, pulse length, and coherence sufficiently unique to justify establishing a user facility at this time? To fulfill this two-point charge, special emphasis was placed by the workshop committee on two goals. First, scientists were invited who work in areas where the lack of powerful, tunable VUV is a limitation to speak about their current research and to speculate on the science that would be uniquely possible with the ALFF. Second, while many of the same scientists have expertise in using lasers and other VUV sources, it was considered crucial to invite scientists explicitly working on the development of tabletop VUV systems. In addition to addressing the second charge question, the purpose of …
Date:
April 5, 2004
Creator:
Kim, K. J.
Object Type:
Report
System:
The UNT Digital Library
Energy Efficient Building Equipment and Envelope Technologies: Final Report
Objectives of this project under this cooperative agreement are to evaluate the energy efficiency and performance enhancements of a pulsed thermal expansion valve (TXV), its cost and reliability. This device could replace the currently used devices, a capillary tube and modulating TXVs, in household and commercial refrigeration and air conditioners. Determination of the economics and first cost of such devices, once performance enhancements have been defined, shall be performed and reported. This work shall be accomplished with the support of commercial partners in the HVAC and R industries. The reliability of the pulsed TXV shall also be determined, which is an important factor for its commercial success.
Date:
January 5, 2004
Creator:
Rockenfeller, Uwe
Object Type:
Report
System:
The UNT Digital Library
Performance analysis of parallel supernodal sparse LU factorization
We investigate performance characteristics for the LU factorization of large matrices with various sparsity patterns. We consider supernodal right-looking parallel factorization on a bi-dimensional grid of processors, making use of static pivoting. We develop a performance model and we validate it using the implementation in SuperLU-DIST, the real matrices and the IBM Power3 machine at NERSC. We use this model to obtain performance bounds on parallel computers, to perform scalability analysis and to identify performance bottlenecks. We also discuss the role of load balance and data distribution in this approach.
Date:
February 5, 2004
Creator:
Grigori, Laura & Li, Xiaoye S.
Object Type:
Article
System:
The UNT Digital Library
IRRADIATION EFFECTS ON THE PHYSICAL CHARACTERISTICS OF SEWAGE SLUDGE
The radiation effects on the physical characteristic of the sewage sludge were studied in order to obtain information which will be used for study on the enhancement of the sludge's dewaterability. Water contents, capillary suction time, zeta potential, irradiation dose, sludge acidity, total solid concentration, sludge particle size and microbiology before and after irradiation were investigated. Irradiation gave an effect on physical characteristics sludge. Water content in sludge cake could be reduced by irradiation at the dose of 10kGy.
Date:
October 5, 2004
Creator:
Lee, M. J.; Lee, J. K.; Yoo, D. H. & Ho, K.
Object Type:
Article
System:
The UNT Digital Library
cctbx news: Geometry restraints and other new features
None
Date:
August 5, 2004
Creator:
Grosse-Kunstleve, Ralf W.; Afonine, Pavel V. & Adams, Paul D.
Object Type:
Article
System:
The UNT Digital Library
Isotope Production in Light of Increasing Demand
This presentation is a part of the panel discussion on isotope production in light of increasing demand.
Date:
October 5, 2004
Creator:
Patton, B.
Object Type:
Presentation
System:
The UNT Digital Library
Iridium-192 Production for Cancer Treatment
The purpose of this work is to settle a laboratory for Iridium -192 sources production, that is, to determine a wire activation method and to build a hot cell for the wires manipulation, quality control and packaging. The paper relates, mainly, the wire activation method and its quality control. The wire activation is carried out in our nuclear reactor, IEA- R1m.
Date:
October 5, 2004
Creator:
Rostelato, M.E.C.M.; Silva, C.P.G.; Rela, P.R.; Zeituni, C.A.; Lepki, V. & Feher, A.
Object Type:
Article
System:
The UNT Digital Library
INCREASING HEAVY OIL RESERVES IN THE WILMINGTON OIL FIELD THROUGH ADVANCED RESERVOIR CHARACTERIZATION AND THERMAL PRODUCTION TECHNOLOGIES
The overall objective of this project is to increase heavy oil reserves in slope and basin clastic (SBC) reservoirs through the application of advanced reservoir characterization and thermal production technologies. The project involves improving thermal recovery techniques in the Tar Zone of Fault Blocks II-A and V (Tar II-A and Tar V) of the Wilmington Field in Los Angeles County, near Long Beach, California. A primary objective is to transfer technology which can be applied in other heavy oil formations of the Wilmington Field and other SBC reservoirs, including those under waterflood. The thermal recovery operations in the Tar II-A and Tar V have been relatively inefficient because of several producibility problems which are common in SBC reservoirs. Inadequate characterization of the heterogeneous turbidite sands, high permeability thief zones, low gravity oil, and nonuniform distribution of remaining oil have all contributed to poor sweep efficiency, high steam-oil ratios, and early steam breakthrough. Operational problems related to steam breakthrough, high reservoir pressure, and unconsolidated formation sands have caused premature well and downhole equipment failures. In aggregate, these reservoir and operational constraints have resulted in increased operating costs and decreased recoverable reserves. The advanced technologies to be applied include: (1) Develop three-dimensional …
Date:
March 5, 2004
Creator:
Hara, Scott
Object Type:
Report
System:
The UNT Digital Library
Improved Modeling of Transition Metals, Applications to Catalysis and Technetium Chemistry
There is considerable impetus for identification of aqueous OM catalysts as water is the ultimate ''green'' solvent. In collaboration with researchers at Ames Lab, we investigated effective fragment and Monte Carlo techniques for aqueous-phase hydroformylation (HyF). The Rh of the HyF catalyst is weakly aquated, in contrast to the hydride of the Rh-H bond. As the insertion of the olefin C=C into Rh-H determines the linear-to-branched aldehyde ratio, it is reasonable to infer that solvent plays an important role in regiochemistry. Studies on aqueous-phase organometallic catalysis were complemented in studies of the gas-phase reaction. A Rh-carbonyl-phosphine catalyst was investigated. Two of the most important implications of this research include (a) pseudorotation among five-coordinate intermediates is significant in HyF, and (b) CO insertion is the rate-determining step. The latter is in contrast to experimental deductions, highlighting the need for more accurate modeling. To this end, we undertook studies of (a) experimentally relevant PR{sub 3} co-ligands (PMe{sub 3}, PPh{sub 3}, P(p-PhSO{sub 3{sup -}}){sub 3}, etc.), and (b) HyF of propene. For the propylene research, simulations indicated that the linear: branched aldehyde ratio (linear is more desirable) is determined by thermodynamic discrimination of two distinct pathways. Other projects include a theory-experiment study of …
Date:
March 5, 2004
Creator:
Cundari, T. R.
Object Type:
Report
System:
The UNT Digital Library
Development of an energy conservation voluntary agreement pilot project in the steel sector in Shandong
China faces a significant challenge in the years ahead to continue to provide essential materials and products for a rapidly-growing economy while addressing pressing environmental concerns. Energy is a fundamental element of the national economy and the conditions of its use have a direct impact on China's ability to reach its sustainable development goals. China's industrial sector, which accounts for over 70 percent of the nation's total energy consumption each year, provides materials such as steel and cement that build the nation's roads, bridges, homes, offices and other buildings. Industrial products include bicycles, cars, buses, trains, ships, office equipment, appliances, furniture, packaging, pharmaceuticals, and many other components of everyday life in an increasingly modern society. This vital production of materials and products, however, comes with considerable problems. China's industrial sector is heavily dependent on the country's abundant, yet polluting, coal resources. Industrial production locally pollutes the air with emissions of particulates, carbon monoxide, sulfur dioxide, and nitrogen oxides, uses scarce water and oil resources, emits greenhouse gases contributing to the warming global atmosphere, and often produces hazardous and polluting wastes. Fostering innovative approaches to reduce the use of polluting energy resources and to diminish pollution from industrial production that are …
Date:
February 5, 2004
Creator:
Price, Lynn; Yun, Jiang; Worrell, Ernst; Wenwei, Du & Sinton, Jonathan E.
Object Type:
Report
System:
The UNT Digital Library
Acoustic Detecting and Locating Gas Pipe Line Infringement Quarterly Report: Number 6
The power point presentation for the Natural Gas Technologies II Conference held on February 8-11, 2004 in Phoenix AZ, published the presentations made at the conference, therefore required all presenters to submit their presentation prior to November 2003. However in the remainder of year, significant new test data became available which were incorporated in the actual presentation made at the Natural Gas Technologies II Conference. The 6th progress report presents the updated actual slide show used during the paper presentation by Richard Guiler.
Date:
January 5, 2004
Creator:
LOTH, John L.; MORRIS, GARY J.; PALMER, GEORGE M. & GUILER, RICHARD
Object Type:
Report
System:
The UNT Digital Library
DataMover: robust terabyte-scale multi-file replication overwide-area networks
Typically, large scientific datasets (order of terabytes) are generated at large computational centers, and stored on mass storage systems. However, large subsets of the data need to be moved to facilities available to application scientists for analysis. File replication of thousands of files is a tedious, error prone, but extremely important task in scientific applications. The automation of the file replication task requires automatic space acquisition and reuse, and monitoring the progress of staging thousands of files from the source mass storage system, transferring them over the network, archiving them at the target mass storage system or disk systems, and recovering from transient system failures. We have developed a robust replication system, called DataMover, which is now in regular use in High-Energy-Physics and Climate modeling experiments. Only a single command is necessary to request multi-file replication or the replication of an entire directory. A web-based tool was developed to dynamically monitor the progress of the multi-file replication process.
Date:
April 5, 2004
Creator:
Sim, Alex; Gu, Junmin; Shoshani, Arie & Natarajan, Vijaya
Object Type:
Article
System:
The UNT Digital Library
PANEL DISCUSSION: ISOTOPE PRODUCTION IN LIGHT OF INCREASING DEMAND
This presentation is a part of the panel discussion on isotope production in light of increasing demand.
Date:
October 5, 2004
Creator:
Srivastava, S. & del Mastro, N.
Object Type:
Presentation
System:
The UNT Digital Library
Acceleressence: Dark energy from a phase transition at the seesawscale
Simple models are constructed for ''acceleressence'' dark energy: the latent heat of a phase transition occurring in a hidden sector governed by the seesaw mass scale v{sup 2}/M{sub Pl}, where v is the electroweak scale and M{sub Pl} the gravitational mass scale. In our models, the seesaw scale is stabilized by supersymmetry, implying that the LHC must discover superpartners with a spectrum that reflects a low scale of fundamental supersymmetry breaking. Newtonian gravity may be modified by effects arising from the exchange of fields in the acceleressence sector whose Compton wavelengths are typically of order the millimeter scale. There are two classes of models. In the first class the universe is presently in a metastable vacuum and will continue to inflate until tunneling processes eventually induce a first order transition. In the simplest such model, the range of the new force is bounded to be larger than 25 {micro}m in the absence of fine-tuning of parameters, and for couplings of order unity it is expected to be {approx} 100 {micro}m. In the second class of models thermal effects maintain the present vacuum energy of the universe, but on further cooling, the universe will ''soon'' smoothly relax to a matter dominated …
Date:
October 5, 2004
Creator:
Chacko, Z.; Hall, Lawrence J. & Nomura, Yasunori
Object Type:
Article
System:
The UNT Digital Library
Decanting of Neutralized H-Canyon Unirradiated Nuclear Material High Activity Waste Streams
An option to dispose of the High Activity Waste (HAW) stream from the processing of unirradiated materials directly to Saltstone is being evaluated to conserve High Level Waste (HLW) tank farm space and to reduce the future production of HLW glass logs. To meet the Saltstone Waste Acceptance Criteria (WAC), decanting the supernate from precipitated solids was proposed to reduce mercury and radionuclide levels in the waste. Only the caustic supernate will then be sent to Saltstone. Verification that the Saltstone WAC will be met has involved a series of laboratory studies using surrogate and actual HAW solutions from H-Canyon. The initial experiment involved addition of sodium hydroxide (NaOH) to a surrogate HAW test solution and subsequent decanting of the supernate away from the precipitated solids. The chemical composition of the surrogate solution was based on a composition defined from analyses of actual HAW solutions generated during dissolution of unirradiated nuclear materials in H-Canyon [1]. Results from testing the surrogate HAW solution were reported in Reference [2]. Information obtained from the surrogate test solution study was used to define additional experiments on actual HAW solutions obtained from H-Canyon. These experiments were conducted with samples from three different batches of HAW …
Date:
August 5, 2004
Creator:
BRONIKOWSKI, MICHAELG.
Object Type:
Report
System:
The UNT Digital Library
Beam Conditioning and Harmonic Generation in Free ElectronLasers
The next generation of large-scale free-electron lasers (FELs) such as Euro-XFEL and LCLS are to be devices which produce coherent X-rays using Self-Amplified Spontaneous Emission (SASE). The performance of these devices is limited by the spread in longitudinal velocities of the beam. In the case where this spread arises primarily from large transverse oscillation amplitudes, beam conditioning can significantly enhance FEL performance. Future X-ray sources may also exploit harmonic generation starting from laser-seeded modulation. Preliminary analysis of such devices is discussed, based on a novel trial-function/variational-principle approach, which shows good agreement with more lengthy numerical simulations.
Date:
July 5, 2004
Creator:
Charman, A.E.; Penn, G.; Wolski, A. & Wurtele, J.S.
Object Type:
Article
System:
The UNT Digital Library
Numerical Predictions for the Demo Enclosure and Comparison to Experiment
The ''demo enclosure'' is a small box meant to simulate the basic characteristics of an equipment enclosure, but without the complexity of an actual enclosure. Extensive experimental measurements have been made on the enclosure and are summarized in a companion report entitled ''Experimental Measurements of the Demo Enclosure''. In this report, we will summarize the associated numerical modeling of the enclosure's structural vibration and radiated sound field using finite and boundary element techniques. One of the main goals of the report is to establish useful modeling guidelines for finite and boundary element analyses of enclosures. Producing accurate predictions is of primary importance, but ease of implementation is also important. We will try to demonstrate that it is not always beneficial to try to duplicate all the enclosure's structural complexity in the finite and boundary element models because errors inevitably occur and it is frequently difficult to adjust the models without considerable effort. For example, it is relatively simple to produce accurate models for shelves and enclosures separately, but their interconnections are much more difficult to represent. When the models are combined into much larger finite element models, it becomes difficult and time consuming to optimize the modeling of the interconnections. …
Date:
February 5, 2004
Creator:
Fahnline, JB; Campbell, RL & Hambric, SA
Object Type:
Report
System:
The UNT Digital Library
ULTRASENSITIVE HIGH-TEMPERATURE SELECTIVE GAS DETECTION USING PIEZOELECTRIC MICROCANTILEVERS
We have obtained very promising results in the Phase I study. Specifically, for temperature effects, we have established that piezoelectric cantilever sensors could retain their resonance peak strength at high temperatures, i.e., the Q values of the resonance peaks remained above 10 even when the temperature was very close to the Curie temperature. This confirms that a piezoelectric cantilever sensor can be used as a sensor up to its Curie temperature. Furthermore, we have shown that the mass detection sensitivity remained unchanged at different temperatures. For selective gas detection, we have demonstrated selective NH{sub 3} detection using piezoelectric cantilever sensors coated with mesoporous SiO{sub 2}. For high-temperature sensor materials development, we have achieved highly oriented Sr-doped lead titanate thin films that possessed superior dielectric and ferroelectric properties. Such highly oriented films can be microfabricated into high-performance piezoelectric microcantilever sensors that can be used up to 490 C. We have accomplished the goal of Phase I study in exploring the various aspects of a high-temperature gas sensor. We propose to continue the study in Phase II to develop a sensor that is suitable for high-temperature applications using piezoelectrics with a high Curie temperature and by controlling the effects of temperature. The …
Date:
March 5, 2004
Creator:
Shih, Wan Y.; Patil, Tejas; Zhao, Qiang; Chiu, Yi-Shi & Shih, Wei-Heng
Object Type:
Report
System:
The UNT Digital Library
Modal Analysis Using the Singular Value Decomposition
Many methods exist for identifying modal parameters from experimental transfer function measurements. For frequency domain calculations, rational fraction polynomials have become the method of choice, although it generally requires the user to identify frequency bands of interest along with the number of modes in each band. This process can be tedious, especially for systems with a large number of modes, and it assumes the user can accurately assess the number of modes present in each band from frequency response plots of the transfer functions. When the modal density is high, better results can be obtained by using the singular value decomposition to help separate the modes before the modal identification process begins. In a typical calculation, the transfer function data for a single frequency is arranged in matrix form with each column representing a different drive point. The matrix is input to the singular value decomposition algorithm and left- and right-singular vectors and a diagonal singular value matrix are computed. The calculation is repeated at each analysis frequency and the resulting data is used to identify the modal parameters. In the optimal situation, the singular value decomposition will completely separate the modes from each other, so that a single transfer …
Date:
February 5, 2004
Creator:
Fahnline, J. B.; Campbell, R. L. & Hambric, S. A.
Object Type:
Report
System:
The UNT Digital Library
The Advanced Chemistry Basins Project: Final Report
In the next decades, oil exploration by majors and independents will increasingly be in remote, inaccessible areas, or in areas where there has been extensive shallow exploration but deeper exploration potential may remain; areas where the collection of data is expensive, difficult, or even impossible, and where the most efficient use of existing data can drive the economics of the target. The ability to read hydrocarbon chemistry in terms of subsurface migration processes by relating it to the evolution of the basin and fluid migration is perhaps the single technological capability that could most improve our ability to explore effectively because it would allow us to use a vast store of existing or easily collected chemical data to determine the major migration pathways in a basin and to determine if there is deep exploration potential. To this end a the DOE funded a joint effort between California Institute of Technology, Cornell University, and GeoGroup Inc. to assemble a representative set of maturity and maturation kinetic models and develop an advanced basin model able to predict the chemistry of hydrocarbons in a basin from this input data. The four year project is now completed and has produced set of public domain …
Date:
April 5, 2004
Creator:
Goddard, William; Meulbroek, Peter; Tang, Yongchun & Cathles, Lawrence, III
Object Type:
Report
System:
The UNT Digital Library
Do you want to build such a machine? : Designing a high energy proton accelerator for Argonne National Laboratory.
Argonne National Laboratory's efforts toward researching, proposing and then building a high-energy proton accelerator have been discussed in a handful of studies. In the main, these have concentrated on the intense maneuvering amongst politicians, universities, government agencies, outside corporations, and laboratory officials to obtain (or block) approval and/or funds or to establish who would have control over budgets and research programs. These ''top-down'' studies are very important but they can also serve to divorce such proceedings from the individuals actually involved in the ground-level research which physically served to create theories, designs, machines, and experiments. This can lead to a skewed picture, on the one hand, of a lack of effect that so-called scientific and technological factors exert and, on the other hand, of the apparent separation of the so-called social or political from the concrete practice of doing physics. An exception to this approach can be found in the proceedings of a conference on ''History of the ZGS'' held at Argonne at the time of the Zero Gradient Synchrotron's decommissioning in 1979. These accounts insert the individuals quite literally as they are, for the most part, personal reminiscences of those who took part in these efforts on the ground …
Date:
April 5, 2004
Creator:
Paris, E.
Object Type:
Report
System:
The UNT Digital Library
The effect of thin film thickness on the incorporation of Mn interstitials in Ga{sub 1-x}Mn{sub x}As
We have investigated the effect of film thickness on the distribution of Mn atoms at various lattice sites in Ga{sub 1-x}Mn{sub x}As thin films. We find that the growth surface acts as a sink facilitating the out-diffusion of Mn interstitials (Mn{sub I}), and thus reducing its concentration in the film. The out-diffused Mn{sub I} accumulate on the surface in a surface oxide layer and do not participate in the ferromagnetism of the film. For thin films less than 15 nm thick, no Mn{sub I} can be detected. Because of the absence of compensating Mn{sub I} defects, higher T{sub C} can be achieved for such extremely thin Ga{sub 1-x}Mn{sub x}As layers. These results agree with our previously suggested Fermi-level-governed upper limit of the T{sub C} of III-Mn-V ferromagnetic semiconductors.
Date:
October 5, 2004
Creator:
Yu, K. M.; Walukiewicz, W.; Wojtowicz, T.; Denlinger, J.; Scarpulla, M. A.; Liu, X. et al.
Object Type:
Article
System:
The UNT Digital Library
Application of Frequency Domain Substructure Synthesis Technique for Plates Loaded with Complex Attachments
Frequency domain substructure synthesis is a modeling technique that enables the prediction of a combined response of individual structures using experimentally measured or numerically predicted frequency response functions (FRFs). The traditional synthesis algorithm [1,2] operates on component impedances and thus generally requires several matrix inversions. An improved algorithm, developed by Jetmundsen et al. [3], requires a single matrix inversion with a completely arbitrary interface definition that can easily incorporate connection impedances. The main limitations of the method are the large data requirements and sensitivity to data truncation. The utility of this technique is demonstrated through a comparison of synthesized and measured admittances of an edge-stiffened plate with attached equipment. The plate mobilities are obtained from a numerical analysis because of the ability to accurately model this structure using a finite element representation. The attachments are characterized experimentally because of their complexity. The sections describe the synthesis technique and show numerical and experimental results for the plate and equipment.
Date:
February 5, 2004
Creator:
Campbell, RL & Hambric, SA
Object Type:
Report
System:
The UNT Digital Library
A proposal for a UPC memory consistency model, v1.0
The memory consistency model in a language defines the order in which the results of write operations maybe observed through read operations. The behavior of a UPC program may depend on the timing of accesses to shared variables, so a program defines a set of possible executions, rather than a single execution. The memory consistency model constrains the set of possible executions for a given program; the user may then rely on properties that are true of all of those executions. The memory consistency model is defined in terms of the read and write operations issued by each thread in naive translation of the code, i.e., without any code transformations by the compiler, with each thread issuing operations as defined by the abstract machine defined in ISO C 5.1.2.3. A UPC compiler or run time system may perform various code transformations to improve performance, so long as they are not visible to the programmer - i.e., provided the set of externally-visible behaviors (the input/output dynamics and volatile behavior defined in ISO C 5.1.2.3) from any execution of the transformed program are identical to those of the original program executing on the abstract machine and adhering to the consistency model defined …
Date:
May 5, 2004
Creator:
Yelick, Katherine; Bonachea, Dan & Wallace, Charles
Object Type:
Report
System:
The UNT Digital Library