Transmission electron microscopy of actinide materials (open access)

Transmission electron microscopy of actinide materials

Actinide metallurgy, crystallography, physics, and chemistry are of great interest due to the unique behavior of the 5f states that dominate the electronic structure. The 5f states produce a wide range of fascinating behaviors in the actinide materials. from superconductivity to exotic magnetism. Accordingly, they are of great interest, but are difficult to work with. Transmission electron microscopy (TEM) can overcome many of the problems of working with actinide materials and can be used to interrogate the atomic and electronic structure of actinide materials. We will cover our capabilities at LLNL: Sample preparation; TEM techniques; and in situ capabilities.
Date: May 30, 2006
Creator: Moore, K
Object Type: Article
System: The UNT Digital Library
HIGH RAPIDITY PHYSICS WITH THE BRAHMS EXPERIMENT. (open access)

HIGH RAPIDITY PHYSICS WITH THE BRAHMS EXPERIMENT.

We report the study of the nuclear modification factor R{sub AuAu} as function of p{sub T} and pseudo-rapidity in Au+Au collisions at top RHIC energy. We find this quantity almost independent of pseudo-rapidity. We use the {bar p}/{pi}{sup -} ratio as a probe of the parton density and the degree of thermalization of the medium formed by the collision. The {bar p}/{pi}{sup -} ratio has a clear rapidity dependence. The combination of these two measurements suggests that the pseudo-rapidity dependence of the R{sub AuAu} results from the competing effects of energy loss in a dense and opaque medium and the modifications of the wave function of the high energy beams in the initial state.
Date: May 30, 2006
Creator: DEBBE,R.
Object Type: Article
System: The UNT Digital Library
Performance Engineering in the Community Atmosphere Model (open access)

Performance Engineering in the Community Atmosphere Model

The Community Atmosphere Model (CAM) is the atmospheric component of the Community Climate System Model (CCSM) and is the primary consumer of computer resources in typical CCSM simulations. Performance engineering has been an important aspect of CAM development throughout its existence. This paper briefly summarizes these efforts and their impacts over the past five years.
Date: May 30, 2006
Creator: Worley, P.; Mirin, A.; Drake, J. & Sawyer, W.
Object Type: Article
System: The UNT Digital Library
Oxidation and aging in U and Pu probed by spin-orbit sum rule analysis: indications for covalent metal-oxide bonds (open access)

Oxidation and aging in U and Pu probed by spin-orbit sum rule analysis: indications for covalent metal-oxide bonds

Actinide physics and chemistry are of great interest due to the unique behavior of the 5f states that dominate the electronic structure. How these states evolve with changes in crystal structure, alloying, oxidation state, and radiation damage is of considerable importance to better understand these materials. Oxidations state: How are the f electrons bonding in actinide oxides? Radiation damage: U and Pu evolve with time due to self-induced radiation damage of the lattice. How does this affect the f states? Our goal here is to examine how oxidation and radiation damage influence the bonding behavior of the 5f electrons in U and Pu.
Date: May 30, 2006
Creator: Moore, K.; Schwartz, A.; Wall, M.; Haire, D. & Der Laan, G. V.
Object Type: Article
System: The UNT Digital Library
CHARGED PARTICLE PRODUCTION AT HIGH RAPIDITY IN p+p COLLISIONS AT RHIC. (open access)

CHARGED PARTICLE PRODUCTION AT HIGH RAPIDITY IN p+p COLLISIONS AT RHIC.

This report describes the recent analysis of identified charged particle production at high rapidity performed on data collected from p+p collisions at RHIC ({radical}s = 200 GeV). The extracted invariant cross-sections compare well to NLO pQCD calculations. However, a puzzling high yield of protons at high rapidity and p{sub T} has been found.
Date: May 30, 2006
Creator: DEBBE,R.
Object Type: Article
System: The UNT Digital Library
The Use of Trust Regions in Kohn-Sham Total EnergyMinimization (open access)

The Use of Trust Regions in Kohn-Sham Total EnergyMinimization

The Self Consistent Field (SCF) iteration, widely used forcomputing the ground state energy and the corresponding single particlewave functions associated with a many-electronatomistic system, is viewedin this paper as an optimization procedure that minimizes the Kohn-Shamtotal energy indirectly by minimizing a sequence of quadratic surrogatefunctions. We point out the similarity and difference between the totalenergy and the surrogate, and show how the SCF iteration can fail whenthe minimizer of the surrogate produces an increase in the KS totalenergy. A trust region technique is introduced as a way to restrict theupdate of the wave functions within a small neighborhood of anapproximate solution at which the gradient of the total energy agreeswith that of the surrogate. The use of trust region in SCF is not new.However, it has been observed that directly applying a trust region basedSCF(TRSCF) to the Kohn-Sham total energy often leads to slowconvergence.We propose to use TRSCF within a direct constrainedminimization(DCM) algorithm we developed in \cite dcm. The keyingredients of theDCM algorithm involve projecting the total energyfunction into a sequence of subspaces of small dimensions and seeking theminimizerof the total energy function within each subspace. Theminimizer of a subspace energy function, which is computed by TRSCF, notonly provides a …
Date: May 30, 2006
Creator: Yang, Chao; Meza, Juan C. & Wang, Lin-wang
Object Type: Article
System: The UNT Digital Library
Multiscale Genetic Structure of Yellowstone Cutthroat Trout in the Upper Snake River Basin. (open access)

Multiscale Genetic Structure of Yellowstone Cutthroat Trout in the Upper Snake River Basin.

Populations of Yellowstone cutthroat trout Oncorhynchus clarkii bouvierii have declined throughout their native range as a result of habitat fragmentation, overharvest, and introductions of nonnative trout that have hybridized with or displaced native populations. The degree to which these factors have impacted the current genetic population structure of Yellowstone cutthroat trout populations is of primary interest for their conservation. In this study, we examined the genetic diversity and genetic population structure of Yellowstone cutthroat trout in Idaho and Nevada with data from six polymorphic microsatellite loci. A total of 1,392 samples were analyzed from 45 sample locations throughout 11 major river drainages. We found that levels of genetic diversity and genetic differentiation varied extensively. The Salt River drainage, which is representative of the least impacted migration corridors in Idaho, had the highest levels of genetic diversity and low levels of genetic differentiation. High levels of genetic differentiation were observed at similar or smaller geographic scales in the Portneuf River, Raft River, and Teton River drainages, which are more altered by anthropogenic disturbances. Results suggested that Yellowstone cutthroat trout are naturally structured at the major river drainage level but that habitat fragmentation has altered this structuring. Connectivity should be restored via …
Date: May 30, 2006
Creator: Cegelski, Christine C. & Campbell, Matthew R.
Object Type: Article
System: The UNT Digital Library
100 Area and 300 Area Component of the RCBRA Fall 2005 Data Compilation (open access)

100 Area and 300 Area Component of the RCBRA Fall 2005 Data Compilation

The purpose of this report is to provide a brief description of the sampling approaches, a description of the samples collected, and the results for the Fall 2005 sampling event. This report presents the methods and results of the work to support the 100 Area and 300 Area Component of the River Corridor Baseline Risk Assessment.
Date: May 30, 2006
Creator: Queen, J.M.
Object Type: Report
System: The UNT Digital Library
A Molecular Dynamics Study of Chemical Reactions of Solid Pentaerythritol Tetranitrate at Extreme Conditions (open access)

A Molecular Dynamics Study of Chemical Reactions of Solid Pentaerythritol Tetranitrate at Extreme Conditions

We have carried out density functional based tight binding (DFTB) molecular dynamics (MD) simulation to study energetic reactions of solid Pentaerythritol Tetranitrate (PETN) at conditions approximating the Chapman-Jouguet (CJ) detonation state. We found that the initial decomposition of PETN molecular solid is characterized by uni-molecular dissociation of the NO{sub 2}groups. Interestingly, energy release from this powerful high explosive was found to proceed in several stages. The large portion of early stage energy release was found to be associated with the formation of H{sub 2}O molecules within a few picoseconds of reaction. It took nearly four times as long for majority of CO{sub 2} products to form, accompanied by a slow oscillatory conversion between CO and CO{sub 2}. The production of N{sub 2} starts after NO{sub 2} loses its oxygen atoms to hydrogen or carbon atoms to form H{sub 2}O or CO. We identified many intermediate species that emerge and contribute to reaction kinetics, and compared our simulation with a thermo-chemical equilibrium calculation. In addition, a detailed chemical kinetics of formation of H{sub 2}O, CO, and CO{sub 2} were developed. Rate constants of formations of H{sub 2}O, CO{sub 2} and N{sub 2} were reported.
Date: May 30, 2006
Creator: Wu, C J; Manaa, M R & Fried, L E
Object Type: Report
System: The UNT Digital Library
OVERVIEW OF MODELING APPROACHES FOR ASSESSING NATURAL SYSTEM PERFORMANCE OF THE HIGH-LEVEL RADIOACTIVE WASTE REPOSITORY AT YUCCA MOUNTAIN, NEVADA (open access)

OVERVIEW OF MODELING APPROACHES FOR ASSESSING NATURAL SYSTEM PERFORMANCE OF THE HIGH-LEVEL RADIOACTIVE WASTE REPOSITORY AT YUCCA MOUNTAIN, NEVADA

For two decades, extensive hydrologic investigations have been conducted for geologic disposal of high-level radioactive waste in fractured volcanic tuffs at Yucca Mountain, Nevada. Extensive field and laboratory geologic, hydrologic, and geochemical testing has provided a large amount of data for developing the conceptual understanding of these processes and parameters for quantifying these processes. A suite of sophisticated numerical models has been developed to assess the long-term performance of the natural barrier of unsaturated zone (UZ) and saturated zone (SZ) to flow of groundwater and transport of radionuclides released from the repository. This work focuses on characterizing surface and subsurface processes of climate change, infiltration, percolation in the UZ and groundwater flow in the SZ, as well as on predicting hydrologic responses of the natural system to the emplacement of waste packages in drifts, including seepage of water into emplacement drifts and radionuclide transport in the UZ and SZ. These models are then abstracted into a total system performance assessment (TSPA) model. The TSPA integrates these natural attributes with features of engineered systems, and through systematic stochastic analyses involving Monte Carlo simulations, predicts the dose consequences and groundwater concentrations for at least 10,000 years for various future climate conditions, waste …
Date: May 30, 2006
Creator: Zhu, M.
Object Type: Article
System: The UNT Digital Library
Time-lapse crosswell seismic and VSP monitoring of injected CO2 ina brine aquifer (open access)

Time-lapse crosswell seismic and VSP monitoring of injected CO2 ina brine aquifer

Seismic surveys successfully imaged a small scale C02injection (1,600 tons) conducted in a brine aquifer of the Frio Formationnear Houston, Texas. These time-lapse bore-hole seismic surveys,crosswell and vertical seismic profile (VSP), were acquired to monitorthe C02 distribution using two boreholes (the new injection well and apre-existing well used for monitoring) which are 30 m apart at a depth of1500 m. The crosswell survey provided a high-resolution image of the C02distribution between the wells via tomographic imaging of the P-wavevelocity decrease (up to 500 mls). The simultaneously acquired S-wavetomography showed little change in S-wave velocity, as expected for fluidsubstitution. A rock physics model was used to estimate C02 saturationsof 10-20 percent from the P-wave velocity change. The VSP survey resolveda large (-70 percent) change in reflection amplitude for the Friohorizon. This C02 induced reflection amplitude change allowed estimationof the C02 extent beyond the monitor well and on 3 azimuths. The VSPresult is compared with numerical modeling of C02 saturations and isseismically modeled using the velocity change estimated in the crosswellsurvey.
Date: May 30, 2006
Creator: Daley, Thomas M.; Myer, Larry R.; Peterson, J. E.; Majer, E. L. & Hoversten, G. M.
Object Type: Article
System: The UNT Digital Library
Timing and prediction of CO2 eruptions from Crystal Geyser, UT (open access)

Timing and prediction of CO2 eruptions from Crystal Geyser, UT

Special instruments were deployed at Crystal Geyser, Utah, in August 2005 creating a contiguous 76-day record of eruptions from this cold geyser. Sensors measured temperature and fluid movement at the base of the geyser. Analysis of the time series that contains the start time and duration of 140 eruptions reveals a striking bimodal distribution in eruption duration. About two thirds of the eruptions were short (7-32 min), and about one third were long (98-113 min). No eruption lasted between 32 and 98 min. There is a strong correlation between the duration of an eruption and the subsequent time until the next eruption. A linear least-squares fit of these data can be used to predict the time of the next eruption. The predictions were within one hour of actual eruption time for 90% of the very short eruptions (7-19 min), and about 45% of the long eruptions. Combined with emission estimates from a previous study, we estimate the annual CO{sub 2} emission from Crystal Geyser to be about 11 gigagrams (11,000 tons).
Date: May 30, 2006
Creator: Gouveia, F J & Friedmann, S J
Object Type: Report
System: The UNT Digital Library
CO-PRODUCTION OF HYDROGEN AND ELECTRICITY USING PRESSURIZED CIRCULATING FLUIDIZED BED GASIFICATION TECHNOLOGY (open access)

CO-PRODUCTION OF HYDROGEN AND ELECTRICITY USING PRESSURIZED CIRCULATING FLUIDIZED BED GASIFICATION TECHNOLOGY

Foster Wheeler has completed work under a U.S. Department of Energy cooperative agreement to develop a gasification equipment module that can serve as a building block for a variety of advanced, coal-fueled plants. When linked with other equipment blocks also under development, studies have shown that Foster Wheeler's gasification module can enable an electric generating plant to operate with an efficiency exceeding 60 percent (coal higher heating value basis) while producing near zero emissions of traditional stack gas pollutants. The heart of the equipment module is a pressurized circulating fluidized bed (PCFB) that is used to gasify the coal; it can operate with either air or oxygen and produces a coal-derived syngas without the formation of corrosive slag or sticky ash that can reduce plant availabilities. Rather than fuel a gas turbine for combined cycle power generation, the syngas can alternatively be processed to produce clean fuels and or chemicals. As a result, the study described herein was conducted to determine the performance and economics of using the syngas to produce hydrogen for sale to a nearby refinery in a hydrogen-electricity co-production plant setting. The plant is fueled with Pittsburgh No. 8 coal, produces 99.95 percent pure hydrogen at a …
Date: May 30, 2006
Creator: Fan, Zhen
Object Type: Report
System: The UNT Digital Library
Mitigating atmospheric effects in high-resolution infra-red surveillance imagery with bispectral speckle imaging (open access)

Mitigating atmospheric effects in high-resolution infra-red surveillance imagery with bispectral speckle imaging

Obtaining a high-resolution image of an object or scene from a long distance away can be very problematic, even with the best optical system. This is because atmospheric blurring and distortion will limit the resolution and contrast of high-resolution imaging systems with substantial sized apertures over horizontal and slant paths. Much of the horizontal and slant-path surveillance imagery we have previously collected and successfully enhanced has been collected at visible wavelengths where atmospheric effects are the strongest. Imaging at longer wavelengths has the benefit of seeing through obscurants or even at night, but even though the atmospheric effects are noticeably reduced, they are nevertheless present, especially near the ground. This paper will describe our recent work on enhanced infrared (IR) surveillance using bispectral speckle imaging. Bispectral speckle imaging in this context is an image postprocessing algorithm that aims to solve the atmospheric blurring and distortion problem of imaging through horizontal or slant path turbulence. A review of the algorithm as well as descriptions of the IR camera and optical systems used in our data collections will be given. Examples of horizontal and slant-path imagery before and after speckle processing will also be presented to demonstrate the resolution improvement gained by …
Date: May 30, 2006
Creator: Carrano, C J
Object Type: Article
System: The UNT Digital Library
Comparison of Marine Microalgae Culture Systems for Fuels Production and Carbon Sequestration (open access)

Comparison of Marine Microalgae Culture Systems for Fuels Production and Carbon Sequestration

The dual problems of global fossil fuels supplies and global warming focus attention on the need to develop technologies that can provide large amounts of renewable fuels without contributing to global warming. The capture of power plant flue gas CO2 using microalgae cultures is one potential technology that could meet this objective. The central R&D issues are the design and operation of low-cost algal mass culture systems and the development of algal strains and cultivation techniques that can achieve very high biomass productivities. The major objective of this project was to develop mass culture techniques that could result in greatly increased biomass productivities, well above the about 50 metric tons per hectare per year (mt/ha/y) currently achievable. In this project, two marine microalgae species, the diatom Cyclotella sp.. and the green alga Tetraselmis sp., were cultivated on seawater in both open ponds and closed photo bioreactors, under a variety of different cultivation conditions. Simultaneous operation of the closed photo bioreactors and open ponds demonstrated similar productivities, under the same operating conditions. Thus the very expensive closed systems do not provide any major or inherent advantages in microalgae production over open ponds. Mutants of Cyclotella sp. were developed that exhibited reduced …
Date: May 30, 2006
Creator: Weissman, Joseph C & Polle, Juergen
Object Type: Report
System: The UNT Digital Library
Infiniband Performance Comparisons of SDR, DDR and Infinipath (open access)

Infiniband Performance Comparisons of SDR, DDR and Infinipath

This technical report will be comparing the performance between the most common infiniband-related technologies currently available. Included will be TCP-based, MPI-based and low-level performance tests to see what performance can be expected from Mellanox's SDR and DDR as well as PathScale's Infinipath. Also, we will be performing comparisons of the Infinipath on both OpenIB as well as PathScale's ipath stack. Infiniband promises to bring high performance interconnects for I/O (filesystem and networking) to a new cost performance level. Thus, LLNL has been evaluating Infiniband for use as a cluster interconnect. Various issues impact the decision of which interconnect to use in a cluster. This technical report will be looking more closely at the actual performance of the major infiniband technologies present today. Performance testing will focus on latency, and bandwidth (both uni and bi-directional) using both TCP and MPI. In addition, we will be looking at an even lower-level (removing most of the upper-level protocols) and seeing what the connection can really do if the TCP or MPI layers were perfectly written.
Date: May 30, 2006
Creator: Minich, M.
Object Type: Report
System: The UNT Digital Library
GAS PHASE MOLECULAR DYNAMICS: HIGH-RESOLUTION SPECTROSCOPIC PROBES OF CHEMICAL DYNAMICS. (open access)

GAS PHASE MOLECULAR DYNAMICS: HIGH-RESOLUTION SPECTROSCOPIC PROBES OF CHEMICAL DYNAMICS.

This research is carried out as part of the Gas Phase Molecular Dynamics group program in the Chemistry Department at Brookhaven National Laboratory. High-resolution spectroscopic tools are developed and applied to problems in chemical dynamics. Recent topics have included the state-resolved studies of collision-induced electronic energy transfer, dynamics of barrierless unimolecular reactions, and the kinetics and spectroscopy of transient species.
Date: May 30, 2006
Creator: Hall, G. E.
Object Type: Article
System: The UNT Digital Library
CFD Simulation of Flow Tones from Grazing Flow past a Deep Cavity (open access)

CFD Simulation of Flow Tones from Grazing Flow past a Deep Cavity

None
Date: May 30, 2006
Creator: Bagwell, T.
Object Type: Report
System: The UNT Digital Library
Tunable Diode Laser Sensor for Monitoring and Control of Harsh Combustion Environments (open access)

Tunable Diode Laser Sensor for Monitoring and Control of Harsh Combustion Environments

This work represents the collaborative effort between American Air Liquide and Physical Sciences, Inc. for developing a sensor based on near-IR tunable diode lasers (TDL). The multi-species capability of the sensor for simultaneous monitoring of CO, O2, and H2O concentration as well as gas temperature is ideal for in-situ monitoring on industrial furnaces. The chemical species targeted are fundamental for controlling the combustion space for improved energy efficiency, reduced pollutants, and improved product quality, when coupling the measurement to a combustion control system. Several add-on modules developed provide flexibility in the system configuration for handling different process monitoring applications. For example, the on-Demand Power Control system for the 1.5 ?m laser is used for high particle density exhaust streams where laser transmission is problematic. For long-distance signal collection a fiber optic communication system is used to reduce noise pick-up. Finally, hardened modules to withstand high ambient temperatures, immune to EMF interference, protection from flying debris, and interfaced with pathlength control laser beam shielding probes were developed specifically for EAF process monitoring. Demonstration of these different system configurations was conducted on Charter Steel's reheat furnace, Imco Recycling, Inc. (now Aleris International, Inc.) aluminum reverberatory furnace, and Gerdau Ameristeel's EAF. Measurements on …
Date: May 30, 2006
Creator: VonDrasek, William & Melsio-Pubill, Anna
Object Type: Report
System: The UNT Digital Library
THE WEAK MIXING ANGLE AND NEW PHYSICS (A TALE OF TWO NUMBERS) (open access)

THE WEAK MIXING ANGLE AND NEW PHYSICS (A TALE OF TWO NUMBERS)

The two best Z pole determinations of sin{sup 2} {theta}{sub W} (m{sub z}){sub {ovr MS}} differ by 3 sigma, a feature lost in global fits and averaging. Individually, sin{sup 2} {theta}{sub W}(m{sub Z}){sub {ovr MS}} = 0.2307(3) obtained from A{sub LR}, taken together with m{sub W} = 80.410(32) GeV, points to a very light Higgs boson, m{sub H} {approx_equal} 12-63 GeV, already ruled out experimentally. it is, however, easily redeemed by low mass scale supersymmetry or models with (effectively) S {approx_equal} -0.12 and T {approx_equal} +0.06. Alternatively, sin{sup 2} {theta}{sub W} (m{sub Z}){sub {ovr MS}} {approx_equal} 0.2320(3) obtained from A{sub FB}(Z {yields} {ovr bb}), suggests a very heavy Higgs, m{sub H} {approx} 500 GeV, along with S {approx_equal} +0.45 which is suggestive of Technicolor models. Future ways to resolve this discrepancy are briefly discussed.
Date: May 30, 2006
Creator: MARCIANO, W.
Object Type: Article
System: The UNT Digital Library
CMC Bench Scale Material Test Plan (open access)

CMC Bench Scale Material Test Plan

The test plan detailed in this topical report supports Task 3.5 of the project titled ''Development of Technologies and Capabilities for Coal Energy Resources - Advanced Gasification Systems Development (AGSD)''. The purpose of these tests is to verify that materials planned for use in an advanced gasifier pilot plant will withstand the environments in a commercial gasifier. Pratt & Whitney Rocketdyne (PWR) has developed this test plan with technical assistance from ceramic scientists at the Dept. of Energy Oak Ridge National Laboratory and Albany Research Center who will perform the environmental exposure tests.
Date: May 30, 2006
Creator: Fitzsimmons, Mark; Pelletier, Gerard & Grimmett, Dave
Object Type: Report
System: The UNT Digital Library
Geometric Representations in the Developmental Monte Carlo Transport Code MC21 (open access)

Geometric Representations in the Developmental Monte Carlo Transport Code MC21

None
Date: May 30, 2006
Creator: Donovan, T & Tyburski, L
Object Type: Report
System: The UNT Digital Library
Half Metallic Digital Ferromagnetic Heterostructure Composed of a (Delta)-doped Layer of Mn in Si (open access)

Half Metallic Digital Ferromagnetic Heterostructure Composed of a (Delta)-doped Layer of Mn in Si

The authors propose and investigate the properties of a digital ferromagnetic heterostructure (DFH) consisting of a {delta}-doped layer of Mn in Si, using ab initio electronic-structure methods. They find that (1) ferromagnetic order of the Mn layer is energetically favorable relative to antiferromagnetic, and (2) the heterostructure is a two-dimensional half metallic system. The metallic behavior is contributed by three majority-spin bands originating from hybridized Mn-d and nearest-neighbor Si-p states, and the corresponding carriers are responsible for the ferromagnetic order in the Mn layer. The minority-spin channel has a calculated semiconducting gap of 0.25 eV. Analysis of the total and partial densities of states, band structure, Fermi surfaces and associated charge density reveals the marked two-dimensional nature of the half metallicity. The band lineup is found to be favorable for retaining the half metal character to near the Curie temperature (T{sub C}). Being Si based and possibly having a high T{sub C} as suggested by an experiment on dilutely doped Mn in Si, the heterostructure may be of special interest for integration into mature Si technologies for spintronic applications.
Date: May 30, 2006
Creator: Qian, M C; Fong, C Y; Liu, K; Pickett, W E; Pask, J E & Yang, L H
Object Type: Article
System: The UNT Digital Library
Neutron Induced Cross Sections for Radiochemistry for Isotopes of Nickel, Copper, and Zinc (open access)

Neutron Induced Cross Sections for Radiochemistry for Isotopes of Nickel, Copper, and Zinc

We have developed a set of modeled neutron induced cross sections for use in radiochemical diagnostics. Local systematics for the input parameters required by the Hauser-Feshbach statistical model were developed and used to calculate neutron induced nuclear reaction cross sections for target isotopes of nickel, copper, and zinc (28 {le} Z {le} 30) for neutron numbers 30 {le} N {le} 40.
Date: May 30, 2006
Creator: Kelley, K.; Hoffman, R. D.; Dietrich, F. S. & Mustafa, M.
Object Type: Report
System: The UNT Digital Library