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Fluidization characteristics of power-plant fly ashes and fly ash-charcoal mixtures.

Description: As a part of the continuing research on aluminum recovery from fly ash by HiChlor process, a plexiglass fluidization column system was constructed for measurement of fluidization parameters for power-plant fly ashes and fly ash-charcoal mixtures. Several bituminous and subbituminous coal fly ashes were tested and large differences in fluidization characteristics were observed. Fly ashes which were mechanically collected fluidized uniformly at low gas flow rates. Most fly ashes which were electr… more
Date: March 1, 1980
Creator: Nguyen, C. T.
open access

Probabilistic Simulation of Subsurface Fluid Flow: A Study Using a Numerical Scheme

Description: There has been an increasing interest in probabilistic modeling of hydrogeologic systems. The classical approach to groundwater modeling has been deterministic in nature, where individual layers and formations are assumed to be uniformly homogeneous. Even in the case of complex heterogeneous systems, the heterogeneities describe the differences in parameter values between various layers, but not within any individual layer. In a deterministic model a single-number is assigned to each hydrogeolo… more
Date: March 1, 1980
Creator: Buscheck, Timothy Eric
open access

A Study of Fundamental Reaction Pathways for Transition Metal Alkyl Complexes: [Parts 1 and 2]

Description: I. This study reports the rapid reaction under mild conditions of internal or terminal alkynes with methyl (acetyl~ acetonato) (triphenylphosphine) nickel (1) in either aromatic or ether solvents. In all cases vinylnickel products 2 are formed by insertion of the alkyne into the nickel=methyl bond. These complexes may be converted into a variety of organic products (e.g. alkenes, esters, vinyl halides) by treatment with appropriate reagents. Unsymmetrical alkynes give selectively the one regioi… more
Date: June 1, 1980
Creator: Huggins, John Mitchell
open access

Parametrization of net radiation at the surface using data from the Wangara experiment

Description: Hourly Wangara boundary layer data (Clark et al., 1971) was used to substantiate previously derived empirical equations of the surface radiation budget. These equations only require measurements taken by a surface observer in order to be evaluated. A parameterization was made for infrared (IR) radiation. From this procedure, a residual radiation was obtained from the measured daytime net radiation data in order to approximate short wave (SW) radiation. Diurnal trends in radiation and other rela… more
Date: Summer 1980
Creator: Edson, Roger T.
open access

Bioassay of Polycyclic Aromatic Hydrocarbons

Description: A positive relationship was found between the photodynamic activity of 24 polycyclic aromatic hydrocarbons versus published results on the mutagenicity, carcinogenicity, and initiation of unscheduled DNA synthesis. Metabolic activation of benzo(a)pyrene resulted in detection of increased mutagenesis in Paramecium tetraurelia as found also in the Ames Salmonella assay. The utility of P. tetraurelia as a biological detector of hazardous polycyclic aromatic hydrocarbons is discussed.
Date: August 1, 1980
Creator: Van Kirk, Edward A.
open access

The Chemistry of HO{Sub 2}NO{Sub 2} and the Photochemistry of the HO{Sub X}-NO{Sub X}-CO{Sub X} System

Description: The objectives of this work were: (1) to investigate formation and destruction reactions of peroxynitric acid, HO{sub 2}NO{sub 2} and (2) to study the photochemistry and kinetics of the HO{sub x} - NO{sub x} - CO{sub x} system were also studied. Investigations were done using infrared spectroscopy to observe the behavior of species involved with the reactions of interest. Several techniques were used, including expansion of reactants into an evacuated cell, static cell decays under constant ill… more
Date: August 1, 1980
Creator: Littlejohn, David
open access

The Application of Some Hartree-Fock Model Calculation to the Analysis of Atomic and Free-Ion Optical Spectra

Description: Techniques for applying ab-initio calculations to the is of atomic spectra are investigated, along with the relationship between the semi-empirical and ab-initio forms of Slater-Condon theory. Slater-Condon theory is reviewed with a focus on the essential features that lead to the effective Hamiltonians associated with the semi-empirical form of the theory. Ab-initio spectroscopic parameters are calculated from wavefunctions obtained via self-consistent field methods, while multi-configuration … more
Date: August 6, 1980
Creator: Hayhurst, Thomas Laine
open access

Solvent Refined Coal (SRC) process: trace elements. Volume III. Pilot plant development work. Part 6. Fate of trace elements in the SRC process.

Description: A study of the forms of trace elements occurring in Solvent Refined Coal has been performed by chemical separation of the Solvent Refined Coal based on differences in the functionality and molecular weight of the organic matrix. Analysis of the fractions separated for various trace elements has revealed associations of certain elements with other elements as well as with certain fractions. The analysis of Solvent Refined Coal I by these methods provided data on the distribution of Ti, V, Ca, S,… more
Date: September 1, 1980
Creator: Weiss, C. S.
open access

Zeeman spectrum of scandium

Description: The spectra of Sc I, Sc II, Sc III, and Sc IV are analyzed through the use of the Zeeman effect. A sliding spark of the author's design is used in conjunction with a 27 kilogauss electromagnet. The spectra have (reciprocal) dispersions of 0.2 to 0.5 A/mm. 10 Sc I levels, 16 Sc II levels and 5 Sc III levels show Zeeman splitting. No Sc IV Zeeman patterns were observed. 2 Sc I, 4 Sc II, and all of the Sc III level data are new.
Date: September 1, 1980
Creator: Lulu, Bruce Alan
open access

Minimizing the Cost of Splitting in Monte Carlo Radiation Transport Simulation

Description: A deterministic analysis of the computational cost associated with geometric splitting/Russian roulette in Monte Carlo radiation transport calculations is presented. Appropriate integro-differential equations are developed for the first and second moments of the Monte Carlo tally as well as time per particle history, given that splitting with Russian roulette takes place at one (or several) internal surfaces of the geometry. The equations are solved using a standard S/sub n/ (discrete ordinates… more
Date: October 1, 1980
Creator: Juzaitis, R. J.
open access

Selectivity in multiple quantum nuclear magnetic resonance

Description: The observation of multiple-quantum nuclear magnetic resonance transitions in isotropic or anisotropic liquids is shown to give readily interpretable information on molecular configurations, rates of motional processes, and intramolecular interactions. However, the observed intensity of high multiple-quantum transitions falls off dramatically as the number of coupled spins increases. The theory of multiple-quantum NMR is developed through the density matrix formalism, and exact intensities are … more
Date: November 1, 1980
Creator: Warren, W. S.
open access

Activity and Diffusion of Metals in Binary Aluminum Alloys

Description: To determine the activity of zinc in Zn-Al alloys, the electromotive force (emf) of the cell: Zn/ZnCl/sub 2/-KC1 (eut)/Zn,Al was measured at temperatures between 569.5 K (296.5C) and 649.5 K (376.5C). The applicability of a two-suffix Margules equation was demonstrated, in good agreement with theoretical expectations. The diffusion coefficient of Zn in Al determined from a planar diffusion model for the experimental data was about 3 x 10/sup -10/ cm/sup 2//sec to 2 x 10/sup -9/ cm/sup 2//sec in… more
Date: December 1, 1980
Creator: Jao, Chiang Seng
open access

Bubble Dynamics at Gas-Evolving Electrodes

Description: Nucleation of bubbles, their growth by diffusion of dissolved gas to the bubble surface and by coalescence, and their detachment from the electrode are all very fast phenomena; furthermore, electrolytically generated bubbles range in size from ten to a few hundred microns; therefore, magnification and high speed cinematography are required to observe bubbles and the phenomena of their growth on the electrode surface. Viewing the action from the front side (the surface on which the bubbles form)… more
Date: December 1, 1980
Creator: Sides, Paul J.
open access

Effect of nuclear spin on chemical reactions and internal molecular rotation

Description: Part I of this dissertation is a study of the magnetic isotope effect, and results are presented for the separation of /sup 13/C and /sup 12/C isotopes. Two models are included in the theoretical treatment of the effect. In the first model the spin states evolve quantum mechanically, and geminate recombination is calculated by numerically integrating the collision probability times the probability the radical pair is in a singlet state. In the second model the intersystem crossing is treated vi… more
Date: December 1, 1980
Creator: Sterna, L.L.
open access

Modeling of Changing Electrode Profiles

Description: A model for simulating the transient behavior of solid electrodes undergoing deposition or dissolution has been developed. The model accounts for ohmic drop, charge transfer overpotential, and mass transport limitations. The finite difference method, coupled with successive overrelaxation, was used as the basis of the solution technique. An algorithm was devised to overcome the computational instabilities associated with the calculations of the secondary and tertiary current distributions. Simu… more
Date: December 1, 1980
Creator: Prentice, Geoffrey Allen
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