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Innovations in the Metallurgy of Lead

Description: From Introduction: "The data reported in this bulletin are largely the result of experiments conducted by the Salt Lake City station of the Bureau of Mines in cooperation with the department of metallurgical research of the University of Utah. The work on the lead is the only one of the phases of the investigations carried on at that station during the years 1914 to 1916."
Date: 1918
Creator: Lyon, Dorsey A. & Ralston, Oliver C.
Partner: UNT Libraries Government Documents Department

Lead: A Materials Survey

Description: Report issued by the U.S. Bureau of Mines discussing a materials survey conducted on lead. Physicality, history, geology, uses, and locations of lead is presented. This report includes maps, tables, illustrations, and photographs.
Date: 1962
Creator: Callaway, H. M.
Partner: UNT Libraries Government Documents Department

Formation of Pyromorphite in Anglesite-Hydroxyapatite Suspensions Under Varying pH Conditions

Description: Addition of phosphate to lead [Pb(ll)l-cOntarninated soil to immobilize soil Pb by formation of pyromorphite has been proposed as an alternative remediation technique. Lead sulfate (PbS04, anglesite), a Pb-bearing form found in contaminated soils and wastes, was reacted with a synthetic phosphate mineral, hydroxyapa$te [Ca5(PO& OH], under constant pH (PH 2-7) and simulated gastric pH conditions (PH varied from 2 to 7 within 30 rein) to assess the effects of reaction kinetics on the formation rate of chloropyromorphite and the volubility of Pb. Under constant pH condition, complete transformation of anglesite to chloropyromorphite, [Pb5(PO&Cl], was obtained at pH 4 and pH 5. At pH 6 and pH 7, the newly formed chloropyromorphite precipitated on the surface of undissolved apatite, The coverage of the apatite surface may reduce apatite dissolution fate and the transformation rate of Pb from anglesite to"chloropyromorphite. Increasing the P/Pb ratio increased the transformation rate, but anglesite was still present after a' 120-min reaction time. in the dynamic pH system, the added apatite was rapidly dissolved at the initial low pH, and complete transformation of anglesite to chloropyromorphite was obtained within 25 min., The soluble Pb level was controlled by the volubility of chloropyromorphite during the entire reaction process. These results demonstrate the effect of reaction kinetics on the formation rate of chloropyromorphite and the mechanisms controlling the solubilization of Pb in the anglesite-apatite system. Furthermore, they illustrate that a complete transformation of ingested anglesite to chloropyromorphite can be achieved. under gastrointestinal tract pH conditions if sufficient phosphate is provided.
Date: October 14, 1998
Creator: Ryan, J.A. & Zhang, P.
Partner: UNT Libraries Government Documents Department

Lead-Based Paint Poisoning Prevention: Summary of Federal Mandates and Financial Assistance for Reducing Hazards in Housing

Description: This report discusses the federal strategy to reduce childhood exposure to lead-based paint (LBP). The federal Lead-Based Paint Poisoning Prevention Act (LBPPPA), as amended, establishes requirements and authorizes funding for the detection and control of LBP hazards in federally assisted housing.
Date: June 12, 2008
Creator: Schierow, Linda-Jo
Partner: UNT Libraries Government Documents Department

Lead Slowing Down Spectrometer Research Plans

Description: The MPACT-funded Lead Slowing Down Spectrometry (LSDS) project has been evaluating the feasibility of using LSDS techniques to assay fissile isotopes in used nuclear fuel assemblies. The approach has the potential to provide considerable improvement in the assay of fissile isotopic masses in fuel assemblies compared to other non-destructive techniques in a direct and independent manner. The LSDS collaborations suggests that the next step to in empirically testing the feasibility is to conduct measurements on fresh fuel assemblies to understand investigate self-attenuation and fresh mixed-oxide (MOX) fuel rodlets so we may betterto understand extraction of masses for 235U and 239Pu. While progressing toward these goals, the collaboration also strongly suggests the continued development of enabling technology such as detector development and algorithm development, thatwhich could provide significant performance benefits.
Date: March 22, 2013
Creator: Warren, Glen A.; Kulisek, Jonathan A.; Gavron, Victor; Danon, Yaron; Weltz, Adam; Harris, Jason et al.
Partner: UNT Libraries Government Documents Department

High Temperature Enthalpies of the Lead Halides: Enthalpies and Entropies of Fusion

Description: The objectives of this investigation were: 1. To establish calorimetrically the transition temperature for the orthorhombic to cubic transition exhibited by PbF₂ and to determine the enthalpy of this transition. 2. To determine if the solid-solid phase transitions claimed in the literature for PbCl₂, PbF₂, PbBr₂, and PbI₂ were of thermodynamic importance, and if so, to determine the enthalpies of transition. 3. To determine if the discontinuous thermal expansions reported by Hsu for the lead halides were of thermodynamic importance. 4. To obtain reliable heat content data for the lead halides in both the solid and liquid states.
Date: June 1970
Creator: Linsey, Clarence W.
Partner: UNT Libraries

An investigation of the effect of tetraethyl lead and ethyl nitrite on the autoignition characteristics of isooctane and triptane

Description: Report presenting an investigation to study the effect of tetraethyl lead, a knock inhibitor, on isooctane. A brief study of ethyl nitrate was also carried out, which demonstrated that it decreased both the delay and critical explosion pressure. Several series of tests were carried out involving different combinations of lead and fuel-air ratio.
Date: June 1950
Creator: Jovellanos, J. U.; Taylor, E. S.; Taylor, C. F. & Leary, W. A.
Partner: UNT Libraries Government Documents Department

In situ measurement of electromigration-induced transient stress in Pb-free Sn-Cu solder joints by synchrotron radiation based X-ray polychromatic microdiffraction

Description: Electromigration-induced hydrostatic elastic stress in Pb-free SnCu solder joints was studied by in situ synchrotron X-ray white beam microdiffraction. The elastic stresses in two different grains with similar crystallographic orientation, one located at the anode end and the other at the cathode end, were analyzed based on the elastic anisotropy of the Beta-Sn crystal structure. The stress in the grain at the cathode end remained constant except for temperature fluctuations, while the compressive stress in the grain at the anode end was built-up as a function of time during electromigration until a steady state was reached. The measured compressive stress gradient between the cathode and the anode is much larger than what is needed to initiate Sn whisker growth. The effective charge number of Beta-Sn derived from the electromigration data is in good agreement with the calculated value.
Date: December 1, 2009
Creator: Chen, Kai; Tamura, Nobumichi; Kunz, Martin; Tu, King-Ning & Lai, Yi-Shao
Partner: UNT Libraries Government Documents Department

Formation of Chloropyromorphite in a Lead-Contaminated Soil Amended with Hydroxyapatite

Description: To confirm conversion of soil Pb to pyromorphite [Pb{sub 5}(PO{sub 4}){sub 3}Cl], a Pb contaminated soil collected adjacent to a historical smelter was reacted with hydroxyapatite in slurries of soil and hydroxyapatite separated by a dialysis membrane and incubated. A crystalline precipitate formed on the dialysis membrane in the slurry systems was identified as chloropyromorphite. Soluble species measured in the soil slurry indicated that dissolution of solid-phase soil Pb was the rate-limiting step for pyromorphite formation. Additionally samples reacted with hydroxyapatite were incubated at field-capacity moisture content. The sequential chemical extraction used to identify species in the field-moist soil incubation experiment showed that hydroxyapatite treatment reduced the first four fractions of extractable Pb and correspondingly increased the recalcitrant extraction residue fraction by 35% of total Pb at 0 d incubation and by 45% after 240 d incubation. the increase in the extraction residue fraction in the 240 d incubation as compared to the 0 d incubation implies that the reaction occurs in the soil but the increase in the hydroxyapatite amended 0 d incubated soil as compared to the control soil illustrates the chemical extraction procedure caused changes in the extractability. Thus, the chemical extraction procedure cannot easily be utilized to confirm changes occurring in the soil as a result of incubation. Extended x-ray absorption fine structure (EXAFS) spectroscopy indicated that the 240 d incubated hydroxyapatite treatment caused a change in the average, local molecular bonding environment of soil Pb. Low-temperature EXAFS spectra (chi data and radial structure functions - RSFs) showed a high degree of similarity between the chemical extraction residue and synthetic pyromorphite. Thus, confirming that the change of soil Pb to pyromorphite is possible by simple amendments of hydroxyapatite to soil.
Date: July 14, 2000
Partner: UNT Libraries Government Documents Department

INEEL Lead Recycling in a Moratorium Environment

Description: Since 1999, the Idaho National Engineering and Environmental Laboratory (INEEL) Lead Project successfully recycled over 700,000 pounds of excess INEEL lead to the private sector. On February 14, 2000, the Secretary of Energy, Bill Richardson, formalized the January 12, 2000, moratorium on recycling radioactive scrap metal that prevented the unrestricted release of recycled scrap metals to the private sector. This moratorium created significant problems for the INEEL lead recycling program and associated plans; however, through the cooperative efforts of the INEEL and Idaho State University as well as innovative planning and creative thinking the recycling issues were resolved. This collaboration has recycled over 160,000 pounds of excess lead to Idaho State University with a cost savings of over $.5M.
Date: February 1, 2003
Creator: Kooda, Kevin Evan; Mc Cray, Casey William; Aitken, Darren William & Galloway, Kelly
Partner: UNT Libraries Government Documents Department

The Disseminated Lead Ores of Southeastern Missouri

Description: From letter of transmittal: The results contained in this report are the product of investigations conducted during the past three months. These investigations were in extension of the work on which was based my report, as State geologist of Missouri, on the lead and zinc deposits of the whole State.
Date: 1896
Creator: Winslow, Arthur
Partner: UNT Libraries Government Documents Department


Description: The nature of impurities found in reclaimed Pb and the effects of their inclusion in castings were investigated. It was concluded that impurities are difficult to remove and may result in unwanted casting characteristics. Recommendations for Pb reclamation are listed. (J.R.D.)
Date: August 1, 1958
Creator: Shepherd, D.M.
Partner: UNT Libraries Government Documents Department


Description: The thermal decomposition of unirradiated and heavily reactor irradiated colloidal alpha -PbN/sub 6/ was studied in the temperature range 195 to 253 deg C and 173 to 239 deg C, respectively. The irradiation vastly reduces the induction and acceleratory periods found with unirradiated material and increases the maximum rate and the rate of the final decay. The maximum rate normally occurs at about 40% decomposition but is shifted to approximately zero time on irradiation. The change in decay rate on irradiation is demonstrated by the two rate constants for decay, k (unirradiated) = 10/sup 12.0 plus or minus 1.0/ exp (-38.3 plus or minus 2.3 kc/m/RT) and k (irradiated) = 10/sup 7.9 plus or minus 1.0/ exp (-25.7 plus or minus 2.4 kc/m/RT). The significant drop in activation energy is possibly associated with changes in electronic excitation energies, while the drop in frequency factor is thought to result from gross structaral changes accompanying the irradiation. The power laws observed in the acceleratory region are interpreted in terms of simultaneous surface and 3- dimensional reactions. (auth)
Date: October 31, 1963
Creator: Jach, J.
Partner: UNT Libraries Government Documents Department

Carbon 14 from Lead Nitrate

Description: Report describing the production of carbon 14 from Pb(NO3)2 in the Oak Ridge Nuclear Reactor via the reaction N14 (n.p.) C14.
Date: 1949
Creator: Goodman, Martin R. & Longacre, Andrew, 1904-
Partner: UNT Libraries Government Documents Department