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Peroxotitanates for Biodelivery of Metals

Description: Metal-based drugs are largely undeveloped in pharmacology. One limiting factor is the systemic toxicity of metal-based compounds. A solid-phase, sequestratable delivery agent for local delivery of metals could reduce systemic toxicity, facilitating new drug development in this nascent area. Amorphous peroxotitanates (APT) are ion exchange materials with high affinity for several heavy metal ions, and have been proposed to deliver or sequester metal ions in biological contexts. In the current study, we tested a hypothesis that APT are able to deliver metals or metal compounds to cells. We exposed fibroblasts (L929) or monocytes (THP1) to metal-APT materials for 72 h in vitro, then measured cellular mitochondrial activity (SDH-MTT method) to assess the biological impact of the metal-APT materials vs. metals or APT alone. APT alone did not significantly affect cellular mitochondrial activity, but all metal-APT materials suppressed the mitochondrial activity of fibroblasts (by 30-65% of controls). The concentration of metal-APT materials required to suppress cellular mitochondrial activity was below that required for metals alone, suggesting that simple extracellular release of the metals from the metal-APT materials was not the primary mechanism of mitochondrial suppression. In contrast to fibroblasts, no metal-APT material had a measurable effect on THP1 monocyte mitochondrial activity, despite potent suppression by metals alone. This latter result suggested that 'biodelivery' by metal-APT materials may be cell type-specific. Therefore, it appears that APT are plausible solid phase delivery agents of metals or metal compounds to some types of cells for potential therapeutic effect.
Date: February 11, 2009
Creator: Hobbs, David & Elvington, M.
Partner: UNT Libraries Government Documents Department


Description: A proposed development program is made for the treatment and disposal of radioactive wastes from Merchant Ship Reactors. Both ion exchange resin and filters are to be used for coolant system cleanup. The development program is concerned with methods of handling and packaging of the spent resin, filter cake and rare gases for safe disposal. (auth)
Date: March 19, 1958
Creator: Higgins, I.R. & Neill, W.J.
Partner: UNT Libraries Government Documents Department


Description: An investigation was conducted to flush the 1BD coolant purification system demineralizer of resin and to measurc the radiation level at pornts on the resin discharge line. It was found that the system demineralizer was satisfactorily flushed of resin. It was also found that the amount removed is measured by the amount required to recharge the demineralizer. (J.R.D.)
Date: January 10, 1961
Partner: UNT Libraries Government Documents Department

Data quality objectives for Ion Exchange Module (IXM) disposition

Description: This Data Quality Objective (DQO) document presents the data needs and accuracy requirements for sampling ion exchange modules at the K Basins, 100 K Area, to determine if there is a hydrogen gas buildup within the modules. This document was produced by PNL, with the assistance of Neptune and Associates, and was partly funded (for facilitator) by DOE-HQ as a demonstration DQO for EM activities. PNL involved a number of PNL, WHC and support contract staff (including external technical consultants) in meetings to define the data needed, along with the necessary accuracy, to resolve issues associated with hydrogen accumulation in Ion Exchange Modules (IXMS) that were generated prior to July 1994 and only have one nuc-fil vent. IXMs generated after July 1994 have multiple nuc-fil vents and do not require sampling. PNL transmitted this DQO to WHC on January 31, 1995. This Supporting Document is to assure that the document is captured into the document retrieval system. WHC review focused on the acceptability of the technical conclusions such that the data collected will meet minimum operational, safety and environmental needs.
Date: January 31, 1995
Creator: Choi, I.
Partner: UNT Libraries Government Documents Department

Development and testing of spheroidal inorganic sorbents

Description: Objective was to develop sodium titanate (ST) microspheres, made by the HMTA (hexamethylenetetramine) internal gelation process, to remove radionuclides and heavy metals from waste streams at DOE sites. to determine the optimum amount of ST that can be embedded in hydrous Ti oxide (HTO) microspheres, batches of 9.2 to 23.3% ST in HTO were prepared. Crush strength of the air-dried microspheres was found to be highest. Sr was removed from simulated supernatant by all composite microspheres; 13.2% ST/HTO worked best.
Date: December 3, 1996
Creator: Collins, J.L.; Egan, B.Z. & Anderson, K.K.
Partner: UNT Libraries Government Documents Department

PRTR ion exchange vault water removal

Description: This report documents the removal of radiologically contaminated water from the Plutonium Recycle Test Reactor (PRTR) ion exchange vault. Approximately 57,000 liters (15,000 gallons) of water had accumulated in the vault due to the absence of a rain cover. The water was removed and the vault inspected for signs of leakage. No evidence of leakage was found. The removal and disposal of the radiologically contaminated water decreased the risk of environmental contamination.
Date: November 1, 1995
Creator: Ham, J.E.
Partner: UNT Libraries Government Documents Department

105 K east ion exchange and cartridge filter restart instrumentation acceptance test report

Description: Acceptance Test Report following the completion of ATP-012 for the 105KE CP-A and CP-A Computer and PLC Panels. The test was conducted from 11/13/95 to 12/11/95. Three test discrepancies were generated during the ATP and all were dispositioned and closed. All sections were completed except Section 5.9 which was deleted per ECN 190556.
Date: January 8, 1996
Creator: Whitehurst, R.
Partner: UNT Libraries Government Documents Department

Speciation and surface interactions of actinides on aged ion-exchange resins

Description: The United States Department of Energy is presently faced with the stabilization and safe disposition of hundreds of metric tons of residue materials resulting from 50+ years of nuclear weapons production activities. These residues encompass a broad range of substrates and radionuclides and include both solid and liquid materials. Combustible residues constitute a significant fraction of the total residue inventory, and an important constituent within the combustible category is spent anion ion-exchange resins. These resins are typically utilized for the separation of plutonium from other radionuclides under strongly acidic nitric or hydrochloric acid solution conditions which favor the formation and partitioning of anionic Pu(IV) nitrato or chloride species. The spent resins are usually rinsed prior to storage as residues to reduce both acid and radionuclide concentrations, but significant radionuclide concentrations remain in these resins, and the long-term effects of concentrated acid and radiolysis on the resin integrity are relatively unexplored. Thus, new research is needed to assess the stability of these resin residues and address the need for further treatment to ensure stability prior to long-term disposal.
Date: September 1, 1997
Creator: Morris, D.E.; Buscher, C.T. & Donohoe, R.J.
Partner: UNT Libraries Government Documents Department

Modeling of Crystalline Silicotitanate Ion Exchange Columns

Description: Non-elutable ion exchange is being considered as a potential replacement for the In-Tank Precipitation process for removing cesium from Savannah River Site (SRS) radioactive waste. Crystalline silicotitanate (CST) particles are the reference ion exchange medium for the process. A major factor in the construction cost of this process is the size of the ion exchange column required to meet product specifications for decontaminated waste. To validate SRS column sizing calculations, SRS subcontracted two reknowned experts in this field to perform similar calculations: Professor R. G. Anthony, Department of Chemical Engineering, Texas A&038;M University, and Professor S. W. Wang, Department of Chemical Engineering, Purdue University. The appendices of this document contain reports from the two subcontractors. Definition of the design problem came through several meetings and conference calls between the participants and SRS personnel over the past few months. This document summarizes the problem definition and results from the two reports.
Date: March 9, 1999
Creator: Walker, D.D.
Partner: UNT Libraries Government Documents Department

Bridged polysilsesquioxanes: A molecular based approach for the synthesis of functional hybrid materials

Description: Bridged polysilsesquioxanes (BPS) are a family of hybrid organic-inorganic materials prepared by sol-gel polymerization of molecular building blocks that contain a variable organic component and at least two trifunctional silyl groups. The resulting xerogels and aerogels have physical and mechanical properties that are strongly influenced by the organic bridging group. This talk focuses on the synthesis of functional bridged polysilsesquioxanes. Incorporation of functional groups that respond to chemical, photochemical, or thermal stimuli can provide handles for modifying bulk morphology and/or provide function. These materials can find use as ion exchange media, chromatographic stationary phases, photoresists and high capacity selective chemical absorbents.
Date: May 9, 2000
Partner: UNT Libraries Government Documents Department

Uptake of actinides and other ions by Diphosil, a new silica-based chelating ion exchange resin

Description: After adsorption of actinides on a phosphonic acid resin, it may be desirable to leave the actinides on the resin. It may be preferable that the polymeric resin matrix be replaced by an inorganic material, in order to prevent formation of radiolytic gases from the organic polymer. A new version of the Diphonix resin has been prepared, where the chelating diphosphonic acid groups are grafted to a silica support. This material is called Diphosil, for Diphonix on silica. This paper reports some results on equilibrium and kinetics of uptake of a number of actinide species and other metal ions of nuclear, environmental, or hydrometallurgical interest by Diphosil.
Date: June 1, 1996
Creator: Chiarizia, R.; Horwitz, E.P.; D`Arcy, K.A.; Alexandratos, S.D. & Trochimczuk
Partner: UNT Libraries Government Documents Department

Maritime Reactor Waste Disposal Studies: Solidification of Ion-Exchange Resin With Portland Cement for Radioactive Waste Disposal

Description: A procedure is reported for the sea disposal. by fixation in concrete. of ion-exchange resins containing sorbed fission products and filtered corrosion products. The results of sea disposal of both treated and untreated resins is presented. For the fixation of nuclear-reactor-system demineralizer resin in cement, a mixture of 2 parts of cement, 1 part of resin, and 1 part of water was found to be optimum. A concrete block prepared by this receipt showed only 0.44% of the gross gamma activity leached after 2540 hr of contact with simulated sea water. The data indicate that very little or no further leaching will occur. (auth)
Date: September 13, 1960
Creator: Holcomb, R. R.
Partner: UNT Libraries Government Documents Department