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  Partner: UNT Libraries Government Documents Department
 Decade: 2000-2009
Microphysical Properties of Single and Mixed-Phase Arctic Clouds Derived from AERI Observations

Microphysical Properties of Single and Mixed-Phase Arctic Clouds Derived from AERI Observations

Date: June 1, 2003
Creator: Turner, David D.
Description: A novel new approach to retrieve cloud microphysical properties from mixed-phase clouds is presented. This algorithm retrieves cloud optical depth, ice fraction, and the effective size of the water and ice particles from ground-based, high-resolution infrared radiance observations. The theoretical basis is that the absorption coefficient of ice is stronger than that of liquid water from 10-13 mm, whereas liquid water is more absorbing than ice from 16-25 um. However, due to strong absorption in the rotational water vapor absorption band, the 16-25 um spectral region becomes opaque for significant water vapor burdens (i.e., for precipitable water vapor amounts over approximately 1 cm). The Arctic is characterized by its dry and cold atmosphere, as well as a preponderance of mixed-phase clouds, and thus this approach is applicable to Arctic clouds. Since this approach uses infrared observations, cloud properties are retrieved at night and during the long polar wintertime period. The analysis of the cloud properties retrieved during a 7 month period during the Surface Heat Budget of the Arctic (SHEBA) experiment demonstrates many interesting features. These results show a dependence of the optical depth on cloud phase, differences in the mode radius of the water droplets in liquid-only and mid-phase ...
Contributing Partner: UNT Libraries Government Documents Department
SciDAC - Center for Plasma Edge Simulation - General Atomics Support of NYU Collaborations

SciDAC - Center for Plasma Edge Simulation - General Atomics Support of NYU Collaborations

Date: June 30, 2009
Creator: Hinton, F.L. & Staff, Project
Description: Methods for implementing Coulomb collisions in particle codes were studied and developed. At first, a lattice-Boltzmann method seemed promising. After considering this in more detail, it was found not to be efficient enough. A method was then sought for implementing collisional effects as changes in particle weights, instead of changes in velocities. Although this may eventually be done, it was decided that a Langevin method would be more straightforward to develop, since it was possible to build on previous work. The rest of the contract period was spent developing the Langevin method, which ultimately resulted in a published paper, in April 2008 [F.L. Hinton, Phys. Plasma 15, 042501 (2008)].
Contributing Partner: UNT Libraries Government Documents Department
Electron exchange-correlation in quantum mechanics

Electron exchange-correlation in quantum mechanics

Date: January 30, 2009
Creator: Ritchie, B
Description: It is shown that Fermi-Dirac statistics is guaranteed by the Dirac current, from which spin-dependent quantum velocity fields and spin-dependent quantum trajectories can be inferred. Pauli's exclusion principle is demonstrated using the spin-dependent quantum trajectories. The Dirac current, unlike the Schroedinger current, is nonzero for stationary bound states due to the permanent magnetic moment of the electron. It is of order c{sup 0} in agreement with observation that Fermi-Dirac statistics is independent of electronic velocity. In summary the physical basis for exchange-correlation is found in Dirac's equation, although Schroedinger's equation may be used to evaluate the Dirac current in the nonrelativistic regime of electronic velocity.
Contributing Partner: UNT Libraries Government Documents Department
Spectrophotometric and Calorimetric Studies of Np(V) Complexation with Acetate at Variable Temperatures (T = 283 - 343 K)

Spectrophotometric and Calorimetric Studies of Np(V) Complexation with Acetate at Variable Temperatures (T = 283 - 343 K)

Date: December 21, 2009
Creator: Rao, Linfeng; Tian, Guoxin; Srinivasan, Thandankorai G.; Zanonato, PierLuigi & Di Bernardo, Plinio
Description: Spectrophotometric titrations were performed to identify the Np(V)/acetate complex and determine the equilibrium constants at variable temperatures (T = 283 - 343 K) and at the ionic strength of 1.05 mol {center_dot} kg{sup -1}. The enthalpy of complexation at corresponding temperatures was determined by microcalorimetric titrations. Results show that the complexation of Np(V) with acetate is weak but strengthened as the temperature is increased. The complexation is endothermic and is entropy-driven. The enhancement of the complexation at elevated temperatures is primarily due to the increasingly larger entropy gain when the solvent molecules are released from the highly-ordered solvation spheres of NpO{sub 2}{sup +} and acetate to the bulk solvent where the degree of disorder is higher at higher temperatures.
Contributing Partner: UNT Libraries Government Documents Department
DEMONSTRATION OF SIMULATED WASTE TRANSFERS FROM TANK AY-102 TO THE HANFORD WASTE TREATMENT FACILITY

DEMONSTRATION OF SIMULATED WASTE TRANSFERS FROM TANK AY-102 TO THE HANFORD WASTE TREATMENT FACILITY

Date: December 3, 2009
Creator: Adamson, D.; Poirier, M. & Steeper, T.
Description: In support of Hanford's AY-102 Tank waste certification and delivery of the waste to the Waste Treatment and Immobilization Plant (WTP), Savannah River National Laboratory (SRNL) was tasked by the Washington River Protection Solutions (WRPS) to evaluate the effectiveness of mixing and transferring the waste in the Double Shell Tank (DST) to the WTP Receipt Tank. This work is a follow-on to the previous 'Demonstration of Internal Structures Impacts on Double Shell Tank Mixing Effectiveness' task conducted at SRNL 1. The objective of these transfers was to qualitatively demonstrate how well waste can be transferred out of a mixed DST tank and to provide insights into the consistency between the batches being transferred. Twelve (12) different transfer demonstrations were performed, varying one parameter at a time, in the Batch Transfer Demonstration System. The work focused on visual comparisons of the results from transferring six batches of slurry from a 1/22nd scale (geometric by diameter) Mixing Demonstration Tank (MDT) to six Receipt Tanks, where the consistency of solids in each batch could be compared. The simulant used in this demonstration was composed of simulated Hanford Tank AZ-101 supernate, gibbsite particles, and silicon carbide particles, the same simulant/solid particles used in the ...
Contributing Partner: UNT Libraries Government Documents Department
Characterization of Oxy-combustion Impacts in Existing Coal-fired Boilers

Characterization of Oxy-combustion Impacts in Existing Coal-fired Boilers

Date: June 30, 2009
Creator: Adams, Bradley; Fry, Andrew; Senior, Constance; Shim, Hong; Wang, Huafeng; Wendt, Jost et al.
Description: This report summarizes Year 1 results of a research program designed to use multi-scale experimental studies and fundamental theoretical models to characterize and predict the impacts of retrofit of existing coal-fired utility boilers for oxy-combustion. Through the course of Year 1 activities, great progress was made toward understanding the issues associated with oxy-combustion retrofit of coal-fired boilers. All four Year 1 milestones and objectives have been, or will be, completed on schedule and within budget. Progress in the four milestone areas may be summarized as follows: • University of Utah has performed size segregated ash composition measurements in the Oxy-Fuel Combustor (OFC). These experiments indicate that oxy-combustion retrofit may impact ash aerosol mineral matter composition. Both flame temperature and flue gas composition have been observed to influence the concentration of calcium, magnesium and iron in the fine particulate. This could in turn impact boiler fouling and slagging. • Sandia National Labs has shown that char oxidation rate is dependent on particle size (for sizes between 60 and 100 microns) by performing fundamental simulations of reacting char particles. These predictions will be verified by making time-resolved optical measurements of char particle temperature, velocity and size in bench-scale experiments before the end ...
Contributing Partner: UNT Libraries Government Documents Department
DEVELOPMENT OF CONTINUOUS SOLVENT EXTRACTION PROCESSES FOR COAL DERIVED CARBON PRODUCTS

DEVELOPMENT OF CONTINUOUS SOLVENT EXTRACTION PROCESSES FOR COAL DERIVED CARBON PRODUCTS

Date: December 31, 2009
Creator: Kennel, Elliot; Chen, Chong; Dadyburjor, Dady; Heavner, Mark; Katakdaunde, Manoj; Magean, Liviu et al.
Description: This NETL sponsored effort seeks to develop continuous technologies for the production of carbon products, which may be thought of as the heavier products currently produced from refining of crude petroleum and coal tars obtained from metallurgical grade coke ovens. This effort took binder grade pitch, produced from liquefaction of West Virginia bituminous grade coal, all the way to commercial demonstration in a state of the art arc furnace. Other products, such as crude oil, anode grade coke and metallurgical grade coke were demonstrated successfully at the bench scale. The technology developed herein diverged from the previous state of the art in direct liquefaction (also referred to as the Bergius process), in two major respects. First, direct liquefaction was accomplished with less than a percent of hydrogen per unit mass of product, or about 3 pound per barrel or less. By contrast, other variants of the Bergius process require the use of 15 pounds or more of hydrogen per barrel, resulting in an inherent materials cost. Second, the conventional Bergius process requires high pressure, in the range of 1500 psig to 3000 psig. The WVU process variant has been carried out at pressures below 400 psig, a significant difference. Thanks ...
Contributing Partner: UNT Libraries Government Documents Department
Shear Strength Measurement Benchmarking Tests for K Basin Sludge Simulants

Shear Strength Measurement Benchmarking Tests for K Basin Sludge Simulants

Date: June 10, 2009
Creator: Burns, Carolyn A.; Daniel, Richard C.; Enderlin, Carl W.; Luna, Maria & Schmidt, Andrew J.
Description: Equipment development and demonstration testing for sludge retrieval is being conducted by the K Basin Sludge Treatment Project (STP) at the MASF (Maintenance and Storage Facility) using sludge simulants. In testing performed at the Pacific Northwest National Laboratory (under contract with the CH2M Hill Plateau Remediation Company), the performance of the Geovane instrument was successfully benchmarked against the M5 Haake rheometer using a series of simulants with shear strengths (τ) ranging from about 700 to 22,000 Pa (shaft corrected). Operating steps for obtaining consistent shear strength measurements with the Geovane instrument during the benchmark testing were refined and documented.
Contributing Partner: UNT Libraries Government Documents Department
Inference of ICF Implosion Core Mix using Experimental Data and Theoretical Mix Modeling

Inference of ICF Implosion Core Mix using Experimental Data and Theoretical Mix Modeling

Date: April 30, 2008
Creator: Welser-Sherrill, L; Haynes, D A; Mancini, R C; Cooley, J H; Tommasini, R; Golovkin, I E et al.
Description: The mixing between fuel and shell materials in Inertial Confinement Fusion (ICF) implosion cores is a current topic of interest. The goal of this work was to design direct-drive ICF experiments which have varying levels of mix, and subsequently to extract information on mixing directly from the experimental data using spectroscopic techniques. The experimental design was accomplished using hydrodynamic simulations in conjunction with Haan's saturation model, which was used to predict the mix levels of candidate experimental configurations. These theoretical predictions were then compared to the mixing information which was extracted from the experimental data, and it was found that Haan's mix model performed well in predicting trends in the width of the mix layer. With these results, we have contributed to an assessment of the range of validity and predictive capability of the Haan saturation model, as well as increased our confidence in the methods used to extract mixing information from experimental data.
Contributing Partner: UNT Libraries Government Documents Department
Technical Review of Law Enforcement Standards and Guides Relative to Incident Management

Technical Review of Law Enforcement Standards and Guides Relative to Incident Management

Date: March 24, 2009
Creator: Stenner, Robert D.; Salter, R.; Stanton, J. R. & Fisher, D.
Description: In an effort to locate potential law enforcement-related standards that support incident management, a team from the Pacific Northwest National Laboratory (PNNL) contacted representatives from the National Institute of Standards-Office of Law Enforcement Standards (NIST-OLES), National Institute of Justice (NIJ), Federal Bureau of Investigation (FBI), Secret Service, ASTM International committees that have a law enforcement focus, and a variety of individuals from local and regional law enforcement organizations. Discussions were held with various state and local law enforcement organizations. The NIJ has published several specific equipment-related law enforcement standards that were included in the review, but it appears that law enforcement program and process-type standards are developed principally by organizations that operate at the state and local level. Input is provided from state regulations and codes and from external non-government organizations (NGOs) that provide national standards. The standards that are adopted from external organizations or developed independently by state authorities are available for use by local law enforcement agencies on a voluntary basis. The extent to which they are used depends on the respective jurisdictions involved. In some instances, use of state and local disseminated standards is mandatory, but in most cases, use is voluntary. Usually, the extent to which ...
Contributing Partner: UNT Libraries Government Documents Department
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