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Diffusion and Leaching of Selected Radionuclides (Iodine-129, Technetium-99, and Uranium) Through Category 3 Waste Encasement Concrete and Soil Fill Material

Description: An assessment of long-term performance of Category 3 waste-enclosing cement grouts requires data about the leachability/diffusion of radionuclide species (iodine-129, technetium-99, and uranium) when the waste forms come in contact with groundwater. Leachability data were collected by conducting dynamic (ANS-16.1) and static leach tests on radionuclide-containing cement specimens. The diffusivity of radionuclides in soil and concrete media was collected by conducting soil-soil and concrete-soil half-cell experiments.
Date: September 24, 2001
Creator: Mattigod, Shas V.; Whyatt, Greg A.; Serne, R. Jeffrey; Martin, P. F.; Schwab, Kristen E. & Wood, Marcus I.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

Thermonuclear Project Semiannual Progress Report: for Period Ending July 31, 1960

Description: From Introduction: "The present semiannual progress report introduces more active consideration than has been given in the past (by us, at least) to the importance of energy degradation in DCX-like devices. The following pages introduce also a new major apparatus designated as DCX-2. Some of these concepts cannot as yet be released publicly and therefore Chap. 3 of this report, covering the DCX-EP-B design, is being issued separately, with restricted distribution, as ORNL-3044."
Date: January 13, 1961
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

Separation of Azeotropes by Means of Diffusion through Porous Membranes

Description: Thesis discussing experiments to separate azeotropes into pure components testing eleven minimum boiling point azeotropic systems: (1) acetone-methanol, (2) carbon tetrachloride-ethyl acetate, (3) cyclohexane-ethanol, (4) benzene-isopropanol, (5) benzene-n-propanol, (6) benzene-cyclohexane, (7) benzene-methanol, (8) benzene-ethanol, (9) acetone-carbon, (10) isopropoanol-water, and (11) ethanol-water.
Date: October 1953
Creator: Hagerbaumer, Donald H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

Self-diffusion of Pb210 and Cl36 in Molten PbCl2-KCl Mixtures in the Region of the Compound 2PbCl2-KCl

Description: The specific goal of the investigation was the measurement, as a function of temperature, of the self-diffusion coefficients of Pb210 and Cl36 in PbCl2-KCl compositions in the region of the first compound, and to calculate from these data the activation energy necessary for the diffusion of these ions.
Date: June 1960
Creator: Tidwell, Troy Haskell
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries

Mega et al. Reply

Description: This article is a reply to a comment by A. Helmstetter and D. Sornette about the article 'Power-Law Time Distribution of Large Earthquakes' from 2003.
Date: March 26, 2004
Creator: Mega, Mirko S.; Allegrini, Paolo; Grigolini, Paolo; Latora, Vito; Palatella, Luigi; Rapisarda, Andrea et al.
Item Type: Refine your search to only Article
Partner: UNT College of Arts and Sciences

Reply to the Comment "Intercluster correlation in Seismicity" by Helmstetter and Sornette

Description: This paper is a reply to the comment by Helmstetter and Sornette titled "Intercluster correlation in Seismicity" which addresses an important point in a paper written by the authors that needs to be clarified.
Date: September 15, 2003
Creator: Mega, Mirko S.; Allegrini, Paolo; Grigolini, Paolo; Latora, Vito; Palatella, Luigi; Rapisarda, Andrea et al.
Item Type: Refine your search to only Paper
Partner: UNT College of Arts and Sciences

Scale dependence of the effective matrix diffusion coefficient:some analytical results

Description: Matrix diffusion is an important process affecting solutetransport in fractured rock, and the matrix diffusion coefficient is akey parameter for describing this process. Previous studies haveindicated that the effective matrix-diffusion coefficient values,obtained from a number of field tracer tests, are enhanced in comparisonwith local values and may increase with test scale. In thiscommunication, we develop analytical expressions for the effective matrixdiffusion coefficient for two simple fracture-matrix systems, anddemonstrate that heterogeneities in the rock matrix at different scalescontribute to the scale dependence of the effective matrix diffusioncoefficient.
Date: May 30, 2005
Creator: Liu, H. H.; Zhang, Y. Q. & Molz, F. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department

Nucleation and Growth of Ice Crystals

Description: From Introduction: "The objective of this investigation was to obtain data which will lead to a better understanding of the mechanism of ice formation in saline water. That is, whether the crystal growth is controlled by heat transfer, nucleation of new layers, or diffusion of matter."
Date: January 1965
Creator: Farrar, John & Hamilton, W. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

Investigation of the Mass Transfer Properties of Saline Water Systems

Description: From Introduction: "This investigation was undertaken in order to obtain the appropriate property data for both binary and muticomponent salt solutions and to determine the usefulness of the simple Nernst-type equations, compared with more exact flux-driving force equations, for predicting species transport in molecular diffusion processes of importance in desalination research. The following sections present the details of the approaches taken to each of the tasks and the results derived from these investigations. Information less essential to the analysis of the results was included in the appendices."
Date: September 1966
Creator: Richardson, John L.; Getz, Richard J. & Segovia, Gilbert
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

Dynamics of Electroencephalogram Entropy and Pitfalls of Scaling Detection

Description: This article discusses dynamics of electroencephalogram entropy and pitfalls of scaling detection. Herein the authors study the time evolution of diffusion entropy to elucidate the scaling of EGG time series.
Date: March 10, 2010
Creator: Ignaccolo, Massimiliano; Latka, Miroslaw; Jernajczyk, Wojciech; Grigolini, Paolo & West, Bruce J.
Item Type: Refine your search to only Article
Partner: UNT College of Arts and Sciences

Nano-crystallization Inhibition in 5 Nm Ru Film Diffusion Barriers for Advanced Cu-interconnect

Description: As the semiconductor industries are moving beyond 22 nm node technology, the currently used stacked Ta/TaN diffusion barrier including a copper seed will be unable to fulfill the requirements for the future technologies. Due to its low resistivity and ability to perform galvanic copper fill without a seed layer, ruthenium (Ru) has emerged as a potential copper diffusion barrier. However, its crystallization and columnar nanostructure have been the main cause of barrier failures even at low processing temperatures (300 oC -350 oC). In this study, we have proposed and evaluated three different strategies to improve the performance of the ultrathin Ru film as a diffusion barrier for copper. The first study focused on shallow surface plasma irradiation/amorphization and nitridation of 5 nm Ru films. Systematic studies of amorphization and nitrogen incorporation versus sample bias were performed. XPS, XRD and RBS were used to determine the physico-chemical, crystallization and barrier efficiency of the plasma modified Ru barrier. The nitrogen plasma surface irradiation of Ru films at substrate bias voltage of -350 V showed an improved barrier performance up to 400 oC annealing temperatures. The barrier barely started failing at 450 oC due mainly to nitrogen instability. The second study involved only amorphization of the Ru thin film without any nitrogen incorporation. A low energy ion beam irradiation/amorphization on Ru thin film was carried out by using 60 KeV carbon ions with different irradiation doses. The irradiation energy was chosen high enough so that the irradiation ions pass through the whole Ru thin film and stop in the SiO2/Si support substrate. The C-ion fluence of 5×1016 atoms/cm2 at 60 KeV made the Ru film near amorphous without changing its composition. XRD and RBS were used to determine the relationship between crystallization and barrier efficiency of the carbon irradiated Ru barrier. The amorphized ...
Date: December 2013
Creator: Sharma, Bed P.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries

Diffusion of heat from a line source in isotropic turbulence

Description: "An experimental and analytical study has been made of some features of the turbulent heat diffusion behind a line heated wire stretched perpendicular to a flowing isotropic turbulence. The mean temperature distributions have been measured with systematic variations in wind speed, size of turbulence-producing grid, and downstream location of heat source. The nature of the temperature fluctuation field has been studied" (p. 1).
Date: June 5, 1951
Creator: Uberoi, Mahinder S. & Corrsin, Stanley
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

A theoretical and experimental study of boric oxide deposition on a surface immersed in an exhaust gas stream from a jet-engine combustor, including a method of calculating deposition rates on surfaces

Description: Report presenting the deposition rate of boric oxide from a stream containing submicron particles, which was found experimentally to fit a molecular diffusion equation. Results regarding boundary-layer studies, deposition studies, deposition tests, and turbojet engine performance are provided.
Date: October 8, 1957
Creator: Setze, Paul C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department

Variation of Critical Parameters Between U-235 Assays of 4.9 Percent and 93.5 Percent

Description: The following report uses empirical relations and the elementary diffusion theory transformation, the EDIT, to predict some of the minimum critical values of the various parameters of interest with reasonable accuracy. This document reports the minimal critical mass, volume, and cylinder diameter for uranium of 4.9% assay.
Date: October 23, 1953
Creator: Henry, Hugh F. & Newlon, C. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department