BIBLIOGRAPHY OF ROVER FUEL PROCESSING AND MOLTEN SALT FLUORIDE VOLATILITY PROCESS DEVELOPMENT STUDIES AT OAK RIDGE NATIONAL LABORATORY

A complete bibliography was assembled of Rover fuel processing and molten salt fluoride volatility processing research at, or sponsored by, Oak Ridge National Laboratory. The bibliography contains open literature references, topical reports, status and progress reports, and technical memoranda. (auth

The epidemiology of diarrhoeal disease in children at Queen Elizabeth Central Hospital, Blantyre, Malawi, 1994-1997

Diarrhoeal disease (DD) is a leading cause of childhood morbidity and mortality in developing countries throughout the world. To begin to understand the burden of DD at Queen Elizabeth Central Hospital (QECH), its seasonality and age distribution, we reviewed inpatient and outpatient records for cases of gastroenteritis between 1994 and 1997. Annually, DO. accounted for an average of 7,300 attendances to the; Under 5's rehydration clinic, 1219 paediatric admissions (12% of all hospitalisations) and 183 deaths in hospitalised children (19% of total). A distinct seasonal pattern was identified with monthly peaks for DD occurring between October to January. Over 75% children (inpatients and outpatients) were below two years of age. During the study period, an increase in the number of outpatient attendances for DD was observed. In contrast, the number of children with a more severe outcome, hospitalisation or death, declined during the study period. This is likely to be explicable by the increasing and appropriate use of oral rehydration therapy. We conclude that DD is a substantial cause of morbidity and mortality in Malawian children. Further studies of the patterns of DD at QECH will be necessary to assess the impact ofDD control programmes

Rotavirus.

Rotavirus, the most common diarrheal pathogen in children worldwide, causes approximately one third of diarrhea-associated hospitalizations and 800,000 deaths per year. Because natural infection reduces the incidence and severity of subsequent episodes, rotavirus diarrhea might be controlled through vaccination. Serotypespecific immunity may play a role in protection from disease. Tetravalent rhesus-human reassortant rotavirus vaccine (RRV-TV) (which contains a rhesus rotavirus with serotype G3 specificity and reassortant rhesus-human rotaviruses with G1, G2, and G4 specificity) provides coverage against the four common serotypes of human rotavirus. In clinical trials in industrialized countries, RRV-TV conferred 49% to 68% protection against any rotavirus diarrhea and 61% to 100% protection against severe disease. This vaccine was licensed by the U.S. Food and Drug Administration on August 31, 1998, and should be cost-effective in reducing diarrheal diseases in industrialized countries. The vaccine's efficacy and cost-effectiveness in developing countries should be evaluated

CHEMICAL TECHNOLOGY DIVISION, UNIT OPERATIONS SECTION MONTHLY PROGRESS REPORT FOR APRIL 1959

A concentration cell electrode was installed in a fritted glass surface and was used to measure the surface KCl concentration while water was being transpired through the surface into a mixed tank of 0.1 M KCl. The results from the first Fluorox run made with crude UF/sub 4/ showed that 85.3% of the theoretical amount of UF/sub 6/ was accounted for, with 17.9% being collected in cold traps and the remainder being consumed in various side reactions. Installation was completed of apparatus to study the electrolytic removal of nickel on an engineering scale from concentrated HRT fuel solution. An extremely low yield stress of 0.02 lb/sq ft was measured for a thoria-urania slurry containing 2.5 wt.% Al/sub 2/O/sub 3/ and spherical particles of 1.7 micron mean diameter. Preliminary data on the rate of uranium sorption on Dowex 21K from sulfate solutions were correlated with a simple spherical diffusion model. Laboratory scale studies to determine the effect of reflux time, HNO/sub 3/ concentration, and air sparge on chloride removal from APPR-type Darex dissolver product showed that an air sparge is definitely beneficial in chloride removal. Preliminary cyclic cleaning tests showed that boiling 25% caustic solution was adequate for cleaning type F (20 micron) porous metal filter elements fouled in the absence of filter aid with siliceous sludge from Darex solvent extraction feed solutions. Sections of unirradiated stainless steel-clad UO/sub 2/, sheared into lengths of 1/2 in., 1 in., 2 in., and 2 3/4 in., were leached free of UO/sub 2/ with 10 M HNO/sub 3/ in 30, 45, 60, and 75 min, respectively. The abrasive blade cost for the removal of inert end adapters from selected reactor assemblies ranges from 12 for the Gas-Cooled Reactor to 19 for Consolidated Edison. A zirconium dissolution was carried to completion at 600 ction prod- C in a NaF-LiF salt mixture containing initially 23 mol per cent ZrF/sub 4/ at an average rate of 1.3 mg/(cm/sup 2/)(min) with an HF feed rate of 2 lb/hr. The thermal conductivity and thermal diffusivity at the center of an 8-in. diameter cake of Darex waste calcined at about 900 ction prod- C were determined as a function of temperature. (For preceding period see CF-59-3-61.) (auth

CHEMICAL TECHNOLOGY DIVISION, UNIT OPERATIONS SECTION MONTHLY PROGRESS REPORT FOR JANUARY 1958

Absolute calibration of neutron yields from a polonium nitrate- fluorocarbon interface gave 8 neutrons/min, sq cm, mc/ml. In two Fluorox fluidized bed reactor runs UF/sub 6/ recoveries of 47 and 70% theoretical were attained. Washing and descaling operations for Loop P-1 have been completed. Preliminary studies of ThO/sub 2/ classification by hydroclones showed that particles as small as 0.5 micron could be classified. Continuous, self- sustaining operation of the Darex dissolver, stripper, and reflux condenser was maintained during a 48-hr period. Uranium losses to the sublimate were less than 0.1% in a 24 hr Zircex run. A 32 hr dissolution run was completed in which a fuel element fabricated of Zircaloy-3 was dissolved in a NaF-ZrF/sub 4/ fused salt. (auth

CHEMICAL TECHNOLOGY DIVISION UNIT OPERATIONS SECTION MONTHLY PROGRESS REPORT, FEBRUARY 1958

The alpha activity for scintillation area measurement was estimated to be 10/sup -6/ of that for the ( alpha ,n) methcd. The UF/sub 6/ recovery during Run FBR-16 was 67.3% of the theoretical recovery for the Fluorox reaction. Hydroclones were used for collection of thoria loop slurries with recoveries exceeding 99%. Flame calcination studies were continued with thoria dispersed in methanol by oxalic acid, using graphite and zirconia reflected burners and acetyleneoxygen flame. Equations for complex ion formation in 4/-H/sub 2/O systems were solved for a few hypothetical solution compositions. A continuous Darex dissolution and stripping run was carried out for 32 hours with chloride removal in the product to 100 ppm. A nine pound section of a fuel element was completely hydrochlorinated in 24 hours with an HCI utilization of 70% and uranium losses to the ZrCl/sub 4/ sublimate of 0.07%. The specific dissolution rate for the fused salt dissolution of Zircaloy-3 was propcrtional to the logarithm of the HF feed rate. One percent of the initial ore resistant t activity and fourteen percent of the initial activity was leached by distilled water from a 900 tained C fired sinter of concentrated fission products in a mix of shale and limestone (Mix 15). (For preceding period see CF- 58-2-139.) (J.R.D.

Point-of-Use Water Treatment and Use among Mothers in Malawi

A national household survey was conducted in Malawi to determine awareness and use of a socially marketed water treatment product. In all, 64% of mothers were aware of the product, and 7% were using it. Both poor and rural mothers had lower awareness and use rates. Targeting promotion to rural populations could enhance program effectiveness

Chemical Technology Division, Unit Operations Section Monthly Progress Report for June 1959

The addition of a surface active agent to an aqueousorganic interface produced a resistance to mass transfer equivalent to slightly more than 1 cm of water. Five semicontinuous Druhm runs were made with 1/2-in. thick MgO liners and terminated due to either failures of the UF/sub 6/ nozzle or a top gasket leak. In preliminary scale-up tests of the flame calcination equipment, a maximum feed rate equivalent to 720 g oxides/hr was achieved using a 3-in. i.d. magnesia reflector with an outside wall temperature of 1500 ction prod- C. In a test with a light water feed, 99% Cu, 25% Ni, and 0% Mn were removed from a UO/ sub 2/SO/sub 4/ solution by electrolysis with a mercury cathode in 7800 ampere hours. The effect of varying the total sulfate concentration on the kinetics of the absorption of uranyl sulfate on Dowex 21K at a uranium concentration of 0.005779 M and a sulfuric acid concentration of 0.020 M was studied in a series of runs using a stirred bath containing enriched uranium. Chloride was removed to 64 ppm in Yankee Atomic and to 70 ppm in APPR solvent extraction feeds using a reference Darex flowsheet with air sparging during a two hour reflux period in the 10-in. prototype titanium feed adjustment tank. Soluble uranium contained in a filter cake deposited onto a 20 micron porous metallic star shaped filter from approximately twenty-one liters of Darex solvent extraction feed solution was recovered to 99.9% by a single 5 liter water wash of the cake. An experimental Redox solvent extraction program was completed. Shear blade evaluation tests have begun at Birdsboro and Clearing under subcontract and will be completed by July 1. Tests were made on the separation of water associated with sheared material through porous bottom baskets as would be required in wet shearing concepts. Consolidated Edison prototype elements assembled with ductile Coast Metals 50 brazing metal could not be disassembled with the impact wedge previously successfully used to disassemble elements made up with brittle Nicrobraze 50. A reactor and condenser system designed to sublime ZrF/sub 4/ from the hydrofluorinator to a separate receiver at temperatures above 902 ction prod- C was operated at condensation rates between 150 and 500 g per hour of ZrF/sub 4/. The thermal conductivities of granular Darex, Purex, and TBP-25 calcined solids were in the range of 0.043 to 0.097 Btu/hr sq ft ( ction prod- F/ft) at room temperature. (For preceding period see CF-59-5-47.) (auth