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DOE pollution prevention in the 21st century. Proceedings (open access)

DOE pollution prevention in the 21st century. Proceedings

This CD-ROM contains the proceedings from the DOE Pollution Prevention in the 21st Century Conference XII held July 9-11, 1996. Topics included model facilities, federal and NEPA stakeholders, microchemistry, source 4 solvents and reduction, education and outreach planning, return on investment, energy management, decontamination and decommissioning, planning and regulations, environmental restoration, solid waste, recycling, affirmative procurement in the executive branch, construction and demolition, international and ISO 14000, and poster sessions.
Date: December 31, 1996
Creator: unknown
System: The UNT Digital Library
A Count Rate Based Contamination Control Standard for Electron Accelerators (open access)

A Count Rate Based Contamination Control Standard for Electron Accelerators

Accelerators of sufficient energy and particle fluence can produce radioactivity as an unwanted byproduct. The radioactivity is typically imbedded in structural materials but may also be removable from surfaces. Many of these radionuclides decay by positron emission or electron capture; they often have long half lives and produce photons of low energy and yield making detection by standard devices difficult. The contamination control limit used throughout the US nuclear industry and the Department of Energy is 1,000 disintegrations per minute. This limit is based on the detection threshold of pancake type Geiger-Mueller probes for radionuclides of relatively high radiotoxicity, such as cobalt-60. Several radionuclides of concern at a high energy electron accelerator are compared in terms of radiotoxicity with radionuclides commonly found in the nuclear industry. Based on this comparison, a count-rate based contamination control limit and associated measurement strategy is proposed which provides adequate detection of contamination at accelerators without an increase in risk.
Date: December 31, 1996
Creator: May, R. T. & Schwahn, S. O.
System: The UNT Digital Library
Radiation Control Aspects of the Civil Construction for a High Power Free Electron Laser (FEL) Facility (open access)

Radiation Control Aspects of the Civil Construction for a High Power Free Electron Laser (FEL) Facility

The paper discusses some of the assumptions and methods employed for the control of ionizing radiation in the specifications for the civil construction of a planned free electron laser facility based on a 200 MeV, 5 mA superconducting recirculation electron accelerator. Consideration is given firstly to the way in which the underlying building configuration and siting aspects were optimized on the basis of the early assumptions of beam loss and radiation goals. The various design requirements for radiation protection are then considered, and how they were folded into an aesthetically pleasing and functional building.
Date: December 31, 1996
Creator: Dunn, T.; Neil, G. & Stapleton, G.
System: The UNT Digital Library
Long Life ZnO-TiO2 and Novel Sorbents (open access)

Long Life ZnO-TiO2 and Novel Sorbents

Combined cycles (combinations of a gas turbine and a steam bottoming cycle) are the most efficient power generation technology, while coal is the lowest cost fuel. Therefore, the combination of Coal Gasifiers and Combined Cycles is predicted to be the lowest cost source of baseload electric power in the next decade. In a GCC, the sulfur and particulates are removed from the gasifier gases before they enter the turbine combuster. While H{sub 2}S (and COS/CS{sub 2}) can be removed effectively by cooling hot gases down to near room temperature and scrubbing them with an aqueous amine solution, removing the H{sub 2}S without cooling the gases (i.e., hot gas cleanup) is more advantageous. The leading hot gas sulfur absorbent uses a regenerable zinc oxide (ZnO) based sorbent, zinc titanate (Zn{sub 2}TiO{sub 4} and/or ZnTiO{sub 3}), to remove the H{sub 2}S and other sulfur compounds from the hot coal gases. The zinc absorbs H{sub 2}S, forming zinc sulfide (ZnS); ZnS is then regenerated with oxygen (air), releasing the sulfur as a concentrated stream of SO{sub 2}. The SO{sub 2} can be converted into sulfuric acid, sulfur, or reacted with calcium carbonate to form calcium sulfate (gypsum). The sorbent may be operated in …
Date: December 31, 1996
Creator: Copeland, Robert J.; Cesario, Mike; Feinberg, Dan; MacQueen, Brent; Sibold, Jack; Windecker, Brian et al.
System: The UNT Digital Library
Ethyl-tertiary-butyl-ether (ETBE) as an aviation fuel: Eleventh international symposium on alcohol fuels (open access)

Ethyl-tertiary-butyl-ether (ETBE) as an aviation fuel: Eleventh international symposium on alcohol fuels

This paper discusses the preliminary flight testing of an aircraft using neat burning ethyl-tertiary-butyl-ether (ETBE) as a fuel. No additional changes were made to the fuel delivery systems which had previously been modified to provide the higher fuel flow rates required to operate the engine on neat ethanol. Air-fuel ratios were manually adjusted with the mixture control. This system allows the pilot to adjust the mixture to compensate for changes in air density caused by altitude, pressure and temperature. The engine was instrumented to measure exhaust gas temperatures (EGT), cylinder head temperatures (CHT), and fuel flows, while the standard aircraft instruments were used to collect aircraft performance data. Baseline engine data for ETBE and Avgas are compared. Preliminary data indicates the technical and economic feasibility of using ETBE as an aviation fuel for the piston engine fleet. Furthermore, the energy density of ETBE qualifies it as a candidate for a turbine engine fuel of which 16.2 billion gallons are used in the US each year.
Date: December 31, 1996
Creator: Maben, G. D.; Shauck, M. E. & Zanin, M. G.
System: The UNT Digital Library
A Workshop on Methods for Neutron Scattering Instrument Design. Introduction and Summary (open access)

A Workshop on Methods for Neutron Scattering Instrument Design. Introduction and Summary

The future of neutron and x-ray scattering instrument development and international cooperation was the focus of the workshop on ``Methods for Neutron Scattering Instrument Design`` September 23-25 at the E.O. Lawrence Berkeley National Laboratory. These proceedings are a collection of a portion of the invited and contributed presentations.
Date: December 31, 1996
Creator: Hjelm, Rex P.
System: The UNT Digital Library
A case for biofuels in aviation (open access)

A case for biofuels in aviation

In the last 15 years, the technical and the economic feasibility of biomass based fuels for general aviation piston engines has been proven. Exhaustive ground and flight tests performed at the Renewable Aviation Fuels Development Center (RAFDC) using ethanol, ethanol/methanol blends, and ETBE have proven these fuels to be superior to aviation gasoline (avgas) in all aspects of performance except range. Two series of Lycoming engines have been certified. Record flights, including a transatlantic flight on pure ethanol, were made to demonstrate the reliability of the fuel. Aerobatic demonstrations with aircraft powered by ethanol, ethanol/methanol, and ETBE were flown at major airshows around the world. the use of bio-based fuels for aviation will benefit energy security, improve the balance of trade, domestic economy, and environmental quality. The United States has the resources to supply the aviation community`s needs with a domestically produced fuel using current available technology. The adoption of a renewable fuel in place of conventional petroleum-based fuels for aviation piston and turbine engines is long overdue.
Date: December 31, 1996
Creator: unknown
System: The UNT Digital Library
Compendium of equations for the design of a very large hadron collider (open access)

Compendium of equations for the design of a very large hadron collider

In this report the author gives several relationships which are used for the preliminary design and to estimate the collider performance. He limits to the case of the performance during storage and colliding mode. These relationships are for: (1)Luminosity and beam-beam tune-shift; (2) microwave longitudinal instability; and (3) synchrotron radiation effects.
Date: December 31, 1996
Creator: Ruggiero, Alessandro G.
System: The UNT Digital Library
Nitric oxide reburning with methane (open access)

Nitric oxide reburning with methane

This paper deals with initial findings from the ongoing, three-year DOE program that began on 02/01/1995. The program involves computer simulation studies to aid in planning and conducting a series of experiments that will extend the knowledge of reburning process. The objective of this work is to find nitric oxide reduction effectiveness for various reburning fuels and identify both homogeneous and heterogeneous reaction mechanisms characterizing NO reduction.
Date: December 31, 1996
Creator: Kumpaty, S. K. & Subramanian, K.
System: The UNT Digital Library
Trading studies of a very large hadron collider (open access)

Trading studies of a very large hadron collider

The author has shown that the design of the ELOISATRON can be approached in five separate steps. In this report he deals with the two major issues of the collider: the size and the strength of the superconducting magnets. In the following he examines two possible approaches. In the first approach, he takes as a starting reference the SSC design with a constant circumference of 87 km. He investigates the energy range of 20 to 100 TeV, and includes the synchrotron radiation effects. The required bending field will be calculated accordingly. In the second approach he follows the same as outlined in the first one, except that he assumes a constant bending field of 13 Tesla. The circumference of the collider will then be determined accordingly. This study will show the consequences of these assumptions and approaches. In his opinion, the feasibility of the ELOISATRON need control of the overall size at one end, and a bending field which is larger than what has been demonstrated recently.
Date: December 31, 1996
Creator: Ruggiero, Alessandro G.
System: The UNT Digital Library
Design considerations and expectations of a very large hadron collider (open access)

Design considerations and expectations of a very large hadron collider

The ELOISATRON Project is a proton-proton collider at very high energy and very large luminosity. The main goal is to determine the ultimate performance that is possible to achieve with reasonable extrapolation of the present accelerator technology. A complete study and design of the collider requires that several steps of investigations are undertaken. The author counts five of such steps as outlined here.
Date: December 31, 1996
Creator: Ruggiero, Alessandro G.
System: The UNT Digital Library
10. international mouse genome conference (open access)

10. international mouse genome conference

Ten years after hosting the First International Mammalian Genome Conference in Paris in 1986, Dr. Jean-Louis Guenet presided over the Tenth Conference at the Pasteur Institute, October 7--10, 1996. The 1986 conference was a satellite to the Human Gene Mapping Workshop and had approximately 50 attendees. The 1996 meeting was attended by 300 scientists from around the world. In the interim, the number of mapped loci in the mouse increased from 1,000 to over 20,000. This report contains a listing of the program and its participants, and two articles that review the meeting and the role of the laboratory mouse in the Human Genome project. More than 200 papers were presented at the conference covering the following topics: International mouse chromosome committee meetings; Mutant generation and identification; Physical and genetic maps; New technology and resources; Chromatin structure and gene regulation; Rate and hamster genetic maps; Informatics and databases; and Quantitative trait analysis.
Date: December 31, 1996
Creator: Meisler, M. H.
System: The UNT Digital Library
Effect of acetylene and ammonia as reburn fuel additions to methane in nitric oxide reburning (open access)

Effect of acetylene and ammonia as reburn fuel additions to methane in nitric oxide reburning

Presented in this paper are the computational results of NO reburning with (a) a combination of methane and acetylene and (b) a combination of methane and ammonia. An updated reaction mechanism that was more comprehensive in terms of predicting the ammonia and isocyanic acid oxidation chemistry was employed to run the CKINTERP program. Using the binary file created by executing the above program and the input stoichiometric ratio conditions, the CHEMKIN package predicted the exit concentrations of various species involved in NO reburning.
Date: December 31, 1996
Creator: Kumpaty, S. K.; Nokku, V. P. & Subramanian, K.
System: The UNT Digital Library
The extracellular matrix of plants: Molecular, cellular and developmental biology (open access)

The extracellular matrix of plants: Molecular, cellular and developmental biology

A symposium entitled ``The Extracellular Matrix of Plants: Molecular, Cellular and Developmental Biology was held in Tamarron, Colorado, March 15--21, 1996. The following topics were explored in addresses by 43 speakers: structure and biochemistry of cell walls; biochemistry, molecular biology and biosynthesis of lignin; secretory pathway and synthesis of glycoproteins; biosynthesis of matrix polysaccharides, callose and cellulose; role of the extracellular matrix in plant growth and development; plant cell walls in symbiosis and pathogenesis.
Date: December 31, 1996
Creator: unknown
System: The UNT Digital Library
Conclusions of the workshop (open access)

Conclusions of the workshop

During this Workshop, it was concluded that a Proton-Proton Collider with an energy of 100 TeV per beam and a luminosity of about 10{sup 35} cm{sup {minus}2} s{sup {minus}1} is feasible. The most important technical requirement for the realization of such a project is a large bending field. For instance, a field of 13 Tesla would be desirable. This is twice the field of the SSC superconducting magnets, which very likely may be achieved in a non-too-far future by extrapolation of the present technology. The design of this Collider would follow very closely the methods used for the design of the SSC and of the LHC, with the major noticeable difference that, because of the larger bending field and the larger beam energy, the performance is determined by the effects of the Synchrotron Radiation in the similar manner they affect the performance of an electron-positron collider. This fact has considerable beneficial consequences since it allows the attainment of large luminosity by reducing the beam dimensions at collision and by requiring, to some degree, less number of particles per beam. On the other end, the losses to synchrotron radiation are to be absorbed by the cryogenic system, and the vacuum system …
Date: December 31, 1996
Creator: Ruggiero, Alessandro G.
System: The UNT Digital Library
Defense Waste Processing Facility radioactive operations -- Part 2, Glass making (open access)

Defense Waste Processing Facility radioactive operations -- Part 2, Glass making

The Savannah River Site`s Defense Waste Processing Facility (DWPF) near Aiken, SC is the nation`s first and world`s largest vitrification facility. Following a ten year construction period and nearly 3 year non-radioactive test program, the DWPF began radioactive operations in March, 1996. The results of the first 8 months of radioactive operations are presented. Topics include facility production from waste preparation batching to canister filling.
Date: December 31, 1996
Creator: Carter, Joe T.; Rueter, Ken J.; Ray, Jeff W. & Hodoh, Ofia
System: The UNT Digital Library
Turbulence and Transport in Enhanced Confinement Regimes of Tokamaks: Simulation and Theory (open access)

Turbulence and Transport in Enhanced Confinement Regimes of Tokamaks: Simulation and Theory

An integrated program of theory and computation has been developed to understand the physics responsible for the favorable confinement trends exhibited by, for example, enhanced reversed shear (ERS) plasmas in TFTR and DIII-D. This paper reports on (1) the quantitative assessment of ExB shear suppression of turbulence by comparison of the linear growth rate calculated from the gyrofluid/comprehensive kinetic codes and the experimentally measured shearing rate in TFTR ERS plasmas; (2) the first self-consistent nonlinear demonstration of ion temperature gradient turbulence reduction due to {angle}P{sub i} driven ExB shear by the global gyrokinetic simulation; (3) a revised neoclassical analysis and gyrokinetic particle simulation results in agreement with trends in ERS plasmas; (4) Shafranov shift induced stabilization of trapped electron mode in ERS plasmas calculated by the gyrofluid code; and (5) new nonlinear gyrokinetic equations for turbulence in core transport barriers.
Date: December 31, 1996
Creator: Hahm, T. S.; Artun, M. & Beer, M. A.
System: The UNT Digital Library
A theoretical overview on single hard diffraction (open access)

A theoretical overview on single hard diffraction

The concept of the Pomeron structure function and its application in Single Hard Diffraction at hadron colliders and in diffractive Deep Inelastic Scattering is critically reviewed. Some alternative approaches are briefly surveyed with a focus on QCD inspired models.
Date: December 31, 1996
Creator: Wuesthoff, M.
System: The UNT Digital Library
MCNP calculations for Russian criticality-safety benchmarks (open access)

MCNP calculations for Russian criticality-safety benchmarks

The current edition of the International Handbook of Evaluated Criticality Safety Benchmark Experiments contains evaluations of 20 critical experiments performed and evaluated by the Institute for Experimental Physics of the Russian Federal Nuclear Center (VNIIEF) at Arzamas-16 and 16 critical experiments performed and evaluated by the Institute for Technical Physics of the Russian Federal Nuclear Center (VNIITF) at Chelyabinsk-70. These fast-spectrum experiments are of particular interest for data testing of ENDF/B-VI because they contain uranium metal systems of intermediate enrichment as well as uranium and plutonium metal systems with reflectors such as graphite, stainless steel, polyethylene, beryllium, and beryllium oxide. This paper presents the first published results for such systems using cross-section libraries based on ENDF/B-VI.
Date: December 31, 1996
Creator: Capell, B.M.; Mosteller, R.D. & Pelowitz, D.B.
System: The UNT Digital Library
A treatment planning comparison of BPA- or BSH-based BNCT of malignant gliomas (open access)

A treatment planning comparison of BPA- or BSH-based BNCT of malignant gliomas

Accurate delivery of the prescribed dose during clinical BNCT requires knowledge (or reasonably valid assumptions) about the boron concentrations in tumor and normal tissues. For conversion of physical dose (Gy) into photon-equivalent dose (Gy-Eq), relative biological effectiveness (RBE) and/or compound-adjusted biological effectiveness (CBE) factors are required for each tissue. The BNCT treatment planning software requires input of the following values: the boron concentration in blood and tumor, RBEs in brain, tumor and skin for the high-LET beam components, the CBE factors for brain, tumor, and skin, and the RBE for the gamma component.
Date: December 31, 1996
Creator: Capala, J.; Coderre, J. A. & Chanana, A. D.
System: The UNT Digital Library
Dislocation imaging of an InAlGaAs opto-electronic modulator using IBICC (open access)

Dislocation imaging of an InAlGaAs opto-electronic modulator using IBICC

This paper presents ion beam induced charge collection (IBICC) contrast images showing regions of differing charge collection efficiency within optoelectronic modulator devices. The experiments were carried out at the Sandia nuclear microprobe using 18 MeV carbon and 2 MeV helium ions. Lines of varying densities are observed to run along the different (110) directions which correlate with misfit dislocations within the 392nm thick strained-layer superlattice quantum well of the modulator structure. Independent cross-sectional TEM studies and the electrical properties of the devices under investigation suggest the presence of threading dislocations in the active device region at a density of {approximately}10{sup 6} cm{sup {minus}2}. However, no clear evidence of threading dislocations was observed in the IBICC images as they are possibly masked by the strong contrast of the misfit dislocations. Charge carrier transport within the modulator is used to explain the observed contrast. The different signal to noise levels and rates of damage of the incident ions are assessed.
Date: December 31, 1996
Creator: Schoene, H.; Lee, S. R. & Briggs, R. D.
System: The UNT Digital Library
Genetic algorithm optimization of atomic clusters (open access)

Genetic algorithm optimization of atomic clusters

The authors have been using genetic algorithms to study the structures of atomic clusters and related problems. This is a problem where local minima are easy to locate, but barriers between the many minima are large, and the number of minima prohibit a systematic search. They use a novel mating algorithm that preserves some of the geometrical relationship between atoms, in order to ensure that the resultant structures are likely to inherit the best features of the parent clusters. Using this approach, they have been able to find lower energy structures than had been previously obtained. Most recently, they have been able to turn around the building block idea, using optimized structures from the GA to learn about systematic structural trends. They believe that an effective GA can help provide such heuristic information, and (conversely) that such information can be introduced back into the algorithm to assist in the search process.
Date: December 31, 1996
Creator: Morris, J. R.; Deaven, D. M.; Ho, K. M.; Wang, C. Z.; Pan, B. C.; Wacker, J. G. et al.
System: The UNT Digital Library
Development of a remote bushing for actinide vitrification (open access)

Development of a remote bushing for actinide vitrification

The Savannah River Site (SRS) and the Savannah River Technology Center (SRTC) are combining their existing experience in handling highly radioactive, special nuclear materials with commercial glass fiberization technology in order to assemble a small vitrification system for radioactive actinide solutions. The vitrification system or {open_quotes}brushing{close_quotes}, is fabricated from platinum-rhodium alloy and is based on early marble remelt fiberization technology. Advantages of this unique system include its relatively small size, reliable operation, geometrical safety (nuclear criticality), and high temperature capability. The bushing design should be capable of vitrifying a number of the actinide nuclear materials, including solutions of americium/curium, neptunium, and possibly plutonium. State of the art, mathematical and oil model studies are being combined with basic engineering evaluations to verify and improve the thermal and mechanical design concepts.
Date: December 31, 1996
Creator: Schumacher, R. F.; Ramsey, W. G. & Johnson, F. M.
System: The UNT Digital Library
Salt-occluded zeolite waste forms: Crystal structures and transformability (open access)

Salt-occluded zeolite waste forms: Crystal structures and transformability

Neutron diffraction studies of salt-occluded zeolite and zeolite/glass composite samples, simulating nuclear waste forms loaded with fission products, have revealed complex structures, with cations assuming the dual roles of charge compensation and occlusion (cluster formation). These clusters roughly fill the 6--8 {angstrom} diameter pores of the zeolites. Samples are prepared by equilibrating zeolite-A with complex molten Li, K, Cs, Sr, Ba, Y chloride salts, with compositions representative of anticipated waste systems. Samples prepared using zeolite 4A (which contains exclusively sodium cations) as starting material are observed to transform to sodalite, a denser aluminosilicate framework structure, while those prepared using zeolite 5A (sodium and calcium ions) more readily retain the zeolite-A structure. Because the sodalite framework pores are much smaller than those of zeolite-A, clusters are smaller and more rigorously confined, with a correspondingly lower capacity for waste containment. Details of the sodalite structures resulting from transformation of zeolite-A depend upon the precise composition of the original mixture. The enhanced resistance of salt-occluded zeolites prepared from zeolite 5A to sodalite transformation is thought to be related to differences in the complex chloride clusters present in these zeolite mixtures. Data relating processing conditions to resulting zeolite composition and structure can be used …
Date: December 31, 1996
Creator: Richardson, J. W. Jr.
System: The UNT Digital Library